JP2003081462A - Printing method and printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that it is troublesome and takes time to remove a jammed paper sheet when a paper sheet stops and piles up in a middle of a paper sheet carrying route due to miss-feeding and jamming. SOLUTION: This printing device includes a controlling means 90 controlling a solenoid 62 and a main motor 20 so that the solenoid 62 is turned off to get in a printing pressure releasing state and selecting designated repetition numbers from a ROM 92 with referring output signals from paper sheet size detecting sensor group 89 and a paper sheet type setting means 73, and controlling a paper feeding motor 45 to repeat carrying motions of a paper feeding roller 35 by designated repetition numbers, and then rotating a plate cylinder 1 based on a signal from a paper sheet tip detecting sensor 41, and a paper sheet 38 is pressed against a master 8 on the plate cylinder 1 with a press roller 21, when a tip of the paper sheet 38 carried by the paper feeding roller 35 is not detected by a first paper sheet sensor 39 within a designated time from a start up point of the paper feeding motor 45.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing method and a printing apparatus, and more particularly to a printing apparatus including a stencil printing apparatus and a printing method using the same.

[0002]

2. Description of the Related Art A stencil master having a laminated structure in which a thermoplastic resin film and a porous support made of Japanese paper fibers or synthetic fibers, or a mixture of Japanese paper fibers and synthetic fibers are laminated (hereinafter, simply referred to as "master"). ")
By contacting the heating element of the thermal head with the heat
Plate-making, and this plate-making master (hereinafter sometimes referred to as "plate-making master") is wound around a rotatable plate cylinder with a structure in which a mesh screen made of resin or metal mesh is wound around multiple layers. , Ink is supplied from the ink supply member provided inside the plate cylinder to the plate-made master on the plate cylinder, and the paper is printed on the plate-made master on the plate cylinder by pressing means such as a press roller, an impression cylinder, or an intermediate pressing roller. There is known a heat-sensitive digital stencil printing apparatus in which the ink is bleeding from the open portion of the plate cylinder and the perforated portion of the master by continuously pressing to perform printing.

In a sheet feeding device used in such a stencil printing machine, generally, a sheet feeding roller for feeding the sheets stacked on the sheet feeding tray and a position facing the sheet feeding roller are provided. Separation pad (separation member) separates and feeds the sheets one by one, and at the timing of the registration roller pair arranged on the downstream side in the sheet conveyance direction, the printing section (plate cylinder and press roller However, a sheet feeding method is adopted in which the sheet is conveyed to a nip portion formed by pressure contact between the plate cylinder and the impression cylinder. Here, the sheet feeding roller and the separating member are also called a separating / conveying unit in a superordinate term. The plate cylinder is also sometimes called a printing drum.

[0004]

However, the slip amount between the paper feed roller and the paper easily changes depending on the difference in the coefficient of friction of the paper used with respect to the paper feed roller and the friction coefficient between the papers. Due to the slip in the separating / conveying means, the conveying length conveyed from the separating / conveying means to the registration roller pair varies.

For example, the top surface of a single-side printed sheet (unprinted surface) stacked below the printing surface (back surface through) on which the ink is attached to the back surface side of the uppermost one-side printed sheet on the paper feed tray. In the case of double-sided printing in which the uppermost single-sided printed sheet is printed on the front side (unprinted side) while separating from), friction between the separation section and the uppermost single-sided printed sheet surface (unprinted side) There is a problem in that the resistance increases, the slip on the paper feed roller and the like becomes large, and the leading edge of the paper on which one side has been printed does not reach the registration roller pair, so that the paper does not feed and jam easily occurs. Also, even when the surface of the paper itself is rough and the coefficient of friction between the paper is high, the above-mentioned transport length is shortened, and the leading edge of the paper does not reach the registration roller pair easily, and a misfeed is likely to occur. There was a problem that became.

Therefore, conventionally, when a sheet is stopped or stays in the middle of the sheet conveyance path due to a non-feed or a jam, an operator or a user (hereinafter, referred to as a "user") handles the jam sheet. It was a troublesome operation and work to remove. In electrostatic copiers, it is possible to reuse jam paper even if it is forcibly discharged if it is not exposed, but in the case of stencil printers, etc., it is easy to come into contact with the plate cylinder where ink is seeping out. , If the ejected paper becomes dirty with the ink and cannot be reused, or if the user takes a long time to remove jammed paper, the ink existing in the perforated part of the master wrapped around the plate cylinder dries. (Generally water-in-oil type (W /
Since O type) emulsion ink is used,
(Water evaporates from the part of the ink that is in contact with the air) and the amount of ink itself decreases, so when printing is restarted after the jam processing, the print image density decreases and image quality deteriorates. There were also problems.

Therefore, the present invention has been made in view of the above circumstances, and reduces the time and the like at the time of jam processing due to a paper feed error such as a non-feed of the paper and does not waste the paper. It is a first object to provide a printing method and a printing device. In addition, it is possible to provide a printing device that can re-feed paper at an optimal timing according to the sheet retention position by detecting the sheet retention position when the sheet remains in the sheet conveyance path. The purpose is 2. In addition, by storing and setting the optimum number of repeats of the transport operation and / or the feeding operation according to the paper type, paper size, and paper feed conditions such as the use of single-sided printed paper in double-sided printing, Thirdly, to provide a printing device that can greatly reduce paper mistakes and jam handling
The purpose of.

[0008]

In order to solve the above problems and achieve the above object, the present invention has the following features in the invention as set forth in each claim. . According to the first aspect of the present invention, there is provided a plate cylinder around which the plate-made master is wound, pressing means for relatively pressing a sheet against the master on the plate cylinder, and timing between the plate cylinder and the pressing means. Registration means for taking and feeding paper,
A printing apparatus having a paper feed table for stacking paper sheets so that the paper sheets can be drawn out and a separation / conveyance means for contacting the paper sheets on the paper feed table and separating and conveying the paper sheets one by one toward the registration means is used. In the printing method, when the paper remains in the paper transport path from the registration means to the separation transport means, the transport operation by the separation transport means and / or the feeding operation by the registration means is repeated a plurality of times,
The printing operation by the plate cylinder and the pressing means is automatically performed after the leading edge of the paper fed from the registration means is detected.

According to a second aspect of the present invention, a plate cylinder around which the plate-made master is wound, a plate cylinder drive means for rotating and driving the plate cylinder, and a press for relatively pressing a sheet against the master on the plate cylinder. Means and pressing drive means for driving the pressing means,
Registration means for feeding the paper at a timing between the plate cylinder and the pressing means, registration driving means for driving the registration means, a paper feed table for stacking the paper so that the paper can be drawn out, and the paper feed A printing apparatus comprising: a separation / conveyance unit that comes into contact with a sheet on a table and separates and conveys the sheets one by one toward the registration unit; and a separation / conveyance drive unit that drives the separation and conveyance unit. Means for detecting the leading edge of the sheet conveyed from the separating and conveying means, and a sheet from the plate cylinder and the pressing means to the registering means. A sheet leading edge detecting means provided on the feeding path for detecting the leading edge of the sheet fed from the registration means, and the separation / conveyance within a predetermined time from the start time of the separation / conveyance driving means. When the leading edge of the sheet conveyed by the step is not detected by the sheet detecting means, or within a predetermined time after the registration driving means is activated, the leading edge of the sheet fed by the registering means is detected by the sheet leading edge detecting means. When it is not detected by the above, it is determined that the sheet remains in the sheet conveyance path, and the separation conveyance means and / or the registration means feed the feeding operation so that the separation conveyance means repeats the conveyance operation a plurality of times. After controlling the registration driving means so as to repeat a plurality of times, the plate cylinder driving means is controlled so as to rotate the plate cylinder based on the paper leading edge detection signal from the paper leading edge detecting means, and the pressing is performed. Means for controlling the pressing drive means so as to relatively press the sheet against the master on the plate cylinder. To.

Here, as the constitution and method of the "pressing means for relatively pressing the sheet against the master on the plate cylinder" in claims 1 and 2, the outer peripheral surface of the plate cylinder is brought into contact with and separated from the outer peripheral surface of the plate cylinder via the master which has been prepressed. A press roller method of pressing a press roller as a free pressing means, an impression cylinder contacting / separating method of performing printing by pressing an impression cylinder as a pressing means to the outer peripheral surface of the plate cylinder through a master that has been prepressed, A plate cylinder contact / separation method in which printing is performed by pressing the plate cylinder against the impression cylinder via the master,
There is a combination method of them. The plate cylinder contact / separation method includes the entire drum contact / separation method in which the entire plate cylinder is pressed toward the impression cylinder, and the medium press roller in the plate cylinder is extruded toward the impression cylinder so that only the plate cylinder (print drum drum plate cylinder) is pressed. There is a plate cylinder extrusion method of pressing. As the plate cylinder extrusion method, for example, JP-A-1
No. 204781, Japanese Patent Laid-Open No. 3- 197078, Japanese Patent Laid-Open No. 3-254948, etc., a metal screen is swollen from the inside to the outside. (Including those that double as).

As a specific example of the "separation / conveyance means for separating and conveying sheets of paper one by one", in addition to the one described in the embodiment described later, for example, a calling roller also called a pickup roller and a pair of upper and lower separation rollers are provided. In addition to the above, a paper separating roller (corresponding to a paper feeding roller that also serves as a separating roller) described in JP-B-5-32296, a roller including a calling roller, a separating roller and a separating pad, and the like are included.

According to a third aspect of the present invention, in the printing apparatus according to the second aspect, a plurality of the sheet detecting means are provided, and the control means is detected by any of the plurality of sheet detecting means. It is characterized in that the separating / conveying driving means is controlled so as to change the conveying start timing of the separating / conveying means according to the position of the leading edge of the sheet.

The invention according to claim 4 is the invention according to claim 2 or 3.
The printing apparatus described above has a storage means for storing the number of repetitions of the above-mentioned transport operation and / or the above-mentioned feeding operation, depending on the paper type, paper size, and paper feed conditions such as use of single-sided printed paper in double-sided printing. However, the control means is
It is characterized in that the number of times of repetition is selected according to the paper feeding condition from the storage means. Here, as specific means for automatically detecting the above-mentioned paper feed conditions, there are a paper type detection means for detecting the paper type, a paper size detection means for detecting the paper size, and the like. Further, as specific means for manually setting the above-mentioned paper feed conditions, a paper type setting means for setting a paper type, a paper size setting means for setting a paper size, and a single-side printed paper for double-sided printing are used. A double-sided printing setting means for setting the above can be cited.

According to a fifth aspect of the present invention, in the printing apparatus according to the fourth aspect, as the type of sheet has a relatively higher coefficient of friction with respect to the separating / conveying means and the sheet size has a larger value, single-sided printing is performed. It is characterized in that the number of times of repetition is set to be larger when using a paper which has been printed on one side in the above-mentioned double-sided printing.

The invention according to claim 6 is the invention according to claims 2 to 5.
In the printing apparatus according to any one of the above, when the carrying operation and / or the feeding operation exceeding the number of repetitions is performed, a notification unit for notifying that the paper is in a jam state is provided. And

The invention according to claim 7 is the invention according to claims 2 to 6.
In the printing apparatus according to any one of items 1 to 3, the pressing unit is provided between a first position that relatively presses a sheet against the master on the plate cylinder and a second position that is separated from the first position. And the displacement means for displacing the pressing means between the first position and the second position, and the separating and conveying means at a predetermined interval while the plate cylinder is rotating, to transfer the sheet. Plate cylinder idle intermittent feed control means for performing an operation related to the skip feed print mode that does not convey and displaces the displacement means, and controls the above when the skip feed print mode is set. The means controls the separation driving means so as to reduce the conveyance speed of the sheet by the separation conveyance means in accordance with the rotation speed of the plate cylinder.

The invention according to claim 8 is the invention according to claims 2 to 7.
The printing apparatus according to any one of the above 1 to 3 is characterized by further comprising a time measuring unit for measuring the predetermined time.

The invention according to claim 9 is the invention according to claims 2 to 7.
In the printing apparatus according to any one of the above, the separation / conveyance driving unit and the registration driving unit are motors driven by pulse input, and the predetermined time is set to It is characterized in that it corresponds to a predetermined number of pulses input.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention including examples with reference to the drawings (hereinafter, simply referred to as "embodiments")
Will be explained. Throughout the embodiments and modified examples, components such as members and components having the same function and shape are designated by the same reference numerals, and the description thereof will be omitted once described. In order to simplify the drawing and the description, even the constituent elements that should be represented in the drawing may be appropriately omitted without special description in the drawing.

(Embodiment 1) First, referring to FIG. 1, a stencil printer 1 as an example of a printer according to Embodiment 1
The overall configuration of 00 will be described. Stencil printer 100
1. As shown in FIG. 1, a plate making apparatus 17 for making a master 8 which is arranged on the upper right side of FIG.
1, a plate cylinder 1 around which a master 8 arranged in the substantially left central portion in FIG. 1 (hereinafter, sometimes referred to as “master 8 that has already been plate-made”) is wound, and a plate cylinder 1 on the plate cylinder 1. The press roller 21 as a pressing unit that presses the sheet 38 against the master 8 that has been plate-prepared, and the sheet 38 that is placed below the plate-making device 17 and is stacked on the sheet feed tray 37 that serves as a sheet feed table, and the plate cylinder 1. A paper feeding device 59 for feeding paper between the press roller 21 and the press roller 21 is provided.

The stencil printing machine 100, in addition to the above-mentioned devices and components, is a well-known and not shown plate cylinder 1.
And a document reading device arranged on the plate making device 17 for reading an image of a document transferred from a document receiving tray, and the plate cylinder 1.
Between the paper discharging device and the document reading device, which is disposed at a position facing the paper feeding device 59 via the paper and discharges the printed paper 38 to a paper discharging tray (not shown). It is provided with a plate discharge device, etc., which is arranged near the left side of the plate cylinder 1 and discharges the used master 8 peeled off from the outer peripheral surface of the plate cylinder 1 to a plate discharge box (not shown). The document reading device, the paper discharge device, and the plate discharge device are described in, for example, Japanese Patent No. 27562.
It has the same structure as that shown in FIG. 1 of Japanese Patent Laid-Open No. 24 (Japanese Patent Application Laid-Open No. 7-52515).

The plate making apparatus 17 includes a master supporting member 8c as a master supporting means for supporting the master 8 so as to be able to be fed in the master transport direction X1, and a thermal head 11 for heating and plate making the master 8 fed according to image information. , The platen roller 10 that conveys the master 8 while rotating the master 8 downstream in the master conveyance direction X1 while pressing the thermal head 11 against the thermal head 11, and while applying a proper tension to the master 8 that has been conveyed by the platen roller 10. A pair of conveying rollers 12 and 12 that conveys to the downstream side of the master conveying direction X1
While applying a proper tension to the cutter 13 that cuts the plate-making master 8 or the plate-making master 8 to a predetermined length, and the master 8 conveyed by the platen roller 10 and the conveying roller pairs 12 and 12. The plate cylinder 1 is provided with a pair of reversing rollers 14, 14 and the like which conveys it toward the expanded clamper 7.

The master 8 is in the form of a continuous sheet and is wound around a synthetic resin roll core 8b to form a master roll 8a.
Is formed. The roll core 8b projects from both end surfaces of the master roll 8a and is formed to be longer than the width of the master 8. In the master roll 8a, the roll cores 8b on both ends are rotatably supported in the counterclockwise direction by a master support member 8c, and are removable from the master support member 8c. The master supporting members 8c on both end sides are slidably attached to a pair of plate-making side plates (not shown) arranged on both left and right sides of the plate-making apparatus 17 along the master transport direction X1. Therefore, the master 8 is supported by the master support member 8c so as to be able to be fed out from the master roll 8a in the master transport direction X1.

The master 8 has a laminated structure in which, for example, a thermoplastic resin film having a thickness of 1 to 5 μm and a porous support made of synthetic fiber are attached. Note that the master is not limited to this, for example, a laminate of a porous support and a thermoplastic resin film made of Japanese paper fibers, or a mixture of Japanese paper fibers and synthetic fibers, or a so-called substantially thermoplastic resin. A master made of only a resin film is also used.

The thermal head 11 is the platen roller 1
The platen roller 10 is provided so as to extend in parallel with the platen roller shaft 0, and can be brought into and out of contact with the platen roller 10 via the master 8 by a contacting / separating mechanism including a cam, a spring member and the like (not shown). The thermal head 11 is biased by the spring member in a direction in which it contacts the platen roller 10. In the main scanning direction of the thermal head 11, a large number of heat generating elements (not shown) are arranged at the portions that come into contact with the platen roller 10 via the master 8. The thermal head 11 selectively heats and melts the master 8 by selectively heating the heating element based on a digital image signal processed and sent by an A / D converter and a plate-making control device (both not shown). -Has a well-known function as plate making means for plate making.

The platen roller 10 is formed integrally with the platen roller shaft via a metal cored bar. The platen roller 10 is rotatable in the clockwise direction because both ends of the platen roller shaft are rotatably supported by the plate making side plate pair. Platen roller 10
Is connected to a stepping motor (not shown) serving as a platen roller drive means via a rotation transmission member (not shown) such as a timing belt or a gear, and is rotationally driven in the clockwise direction. As described above, the master 8 is pulled out from the master roll 8a by rotating the platen roller 10 in the clockwise direction by the stepping motor.

The conveying roller pairs 12, 12 are provided in such a manner that they are pressed against each other by being given a suitable pressing force by a biasing means such as a spring, and both ends of each roller shaft are rotatable with respect to the plate making side plate pair. Since they are supported, they can rotate in opposite directions. The pair of conveying rollers 12 and 12 transmits rotation of a plurality of gears (not shown) so that the upper conveying roller 12 rotates at a peripheral speed (conveying speed) slightly higher than the peripheral speed (conveying speed) of the platen roller 10. Element,
And is connected to the stepping motor via, for example, a powder type electromagnetic clutch (not shown). The drive system around the platen roller 10 and the pair of conveying rollers 12 and 12 via the stepping motor is the same as the rotation transmission mechanism shown in FIG. 2 of JP-A-11-77949 proposed by the applicant of the present application, for example. The mechanism is adopted.

In the above powder type electromagnetic clutch, the platen roller 10 and the conveying roller pair 12 are provided with a front tension as a predetermined tension so that the master 8 is not forcibly pulled out from the nip portion between the platen roller 10 and the thermal head 11. , 12 between the master and the master. As described above, the pair of conveying rollers 12 and 12 are adapted to apply an appropriate front tension to the master 8 which has been prepressed while sliding with the master 8.

The cutter 13 is a publicly known guillotine type equipped with a fixed blade 13b and a movable blade 13a. The cutter 13 is not limited to the guillotine type, but may be a rotary blade moving type in which the movable blade moves while rotating in the master width direction orthogonal to the master transport direction X1.

The pair of reversing rollers 14 and 14 is arranged on the downstream side of the master conveying direction X1 adjacent to the cutter 13, and is formed integrally with a metal shaft. Reversing roller pair 14,
Numerals 14 are provided in such a manner that they are pressed against each other by an appropriate pressing force by an urging means such as a spring, and both ends of each shaft are rotatably supported by the pair of plate making side plates and are opposite to each other. It is freely rotatable in any direction. The upper reversing roller 14 is connected to the stepping motor through a rotation transmitting member (not shown) such as a plurality of gears or belts, and is rotated in the clockwise direction.

The pair of reversing rollers 14 and 14 are set to rotate at a peripheral speed (conveying speed) higher than the peripheral speed (conveying speed) of the platen roller 10 by the rotation transmitting member including the stepping motor. , Master 8 with moderate front tension while sliding with Master 8
It is designed to be given to. Upper reversing roller 14
An electromagnetic clutch (not shown) that connects and disconnects the rotational driving force of the stepping motor to and from itself is provided at the shaft end of the. The electromagnetic clutch is, for example, a powder type electromagnetic clutch or a hysteresis type electromagnetic clutch. Instead of the electromagnetic clutch, a stepping motor independent of the stepping motor may be independently driven. Master transport direction X1 adjacent to the reversing roller pair 14, 14
On the downstream side, a curved guide plate 15 for guiding the front end of the master 8 that has been prepressed to the clamper 7 of the plate cylinder 1 is provided extending in each axial direction of the reversing roller pairs 14, 14.

The plate cylinder 1 comprises a porous cylindrical support cylinder and a mesh screen (not shown) made of a resin or metal mesh wound around a plurality of layers so as to cover the outer periphery of the support cylinder. It has a two-layer structure. The plate cylinder 1 has a well-known configuration including an opening portion 1a (printable area) having a large number of ink-permeable openings and a non-opening portion (non-printable area) provided with a clamper 7 and the like. Have. Plate cylinder 1
Is wound around and fixed to an outer peripheral portion of an end plate flange (not shown), and is rotatably supported around a support shaft that also serves as an ink pipe 5 described later. The plate cylinder 1 is connected to a main motor 20 via a drive transmission means such as a gear or a belt (not shown), and is rotationally driven by the main motor 20 in the arrow direction (clockwise direction). Main motor 20
For this, for example, a DC motor for control is used. The output shaft of the main motor 20 is provided with an optical rotary encoder (not shown) and an encoder sensor (not shown) which sandwiches the optical rotary encoder and generates a pulse in cooperation with the rotary encoder. . This encoder sensor consists of a transmission type optical sensor,
It is used for controlling the rotation speed (printing speed) of the printer, determining the rotation position, and the like.

Inside the plate cylinder 1, which is rotatably supported by a side plate (not shown), the rotational driving force of the main motor 20 is transmitted by drive transmission means such as a gear (not shown) to synchronize with the plate cylinder 1. The ink roller 2 is driven to rotate in the direction of the arrow (clockwise direction) in the figure and contacts the inner peripheral surface of the plate cylinder 1 to supply ink, and the ink roller 2 is arranged in parallel with the ink roller 2 with a slight gap. A doctor roller 3 that forms an ink reservoir 4 having a wedge-shaped cross section with the roller 2 and an ink pipe 5 that supplies ink to the ink reservoir 4 are arranged. The ink roller 2, the doctor roller 3 and the ink pipe 5 constitute ink supply means. Ink pool 4
The ink is sucked by an ink pump (not shown) provided from an ink pack (not shown) provided outside the plate cylinder 1, and is supplied from a supply hole of the ink pipe 5 to be kneaded. The ink in the ink reservoir 4 is supplied in a thin film form on the outer peripheral surface of the ink roller 2 while being measured by the doctor roller 3.
Further, the outer peripheral surface of the ink roller 2 comes into contact with the inner peripheral surface of the supporting cylinder of the plate cylinder 1 to supply the ink to the opening 1a of the plate cylinder 1.

On a part of the outer peripheral surface of the plate cylinder 1 which is not open, a stage 6 made of a ferromagnetic material is provided along one generatrix of the plate cylinder 1, and both sides of the stage 6 are provided. Further, a clamper 7 which is rotatably attached to the clamper shaft and has a rubber magnet that can be opened and closed with respect to the flat surface portion of the stage 6 is provided. The clamper 7 is opened and closed at a predetermined position by an opening / closing device (not shown) provided on the body frame side (not shown). Plate cylinder 1 is clamper 7
Is positioned at the substantially right side shown in FIG. 1, that is, stopped at the plate feeding position. The plate cylinder 1 is configured as a plate cylinder unit that is integrally formed with the ink pack, the ink pump, and the like.
It can be freely inserted into and removed from the main body frame of No. 0 in the axial direction of the ink pipe 5.

In FIG. 1, the end plate flange of the plate cylinder 1 on the back side of the paper and the body frame side near the end plate flange are fed by detecting the rotational position of the plate cylinder 1 as shown in FIG. Components for providing start trigger information to the paper feed motor 45 and the registration motor 50 shown in FIG. 3 of the paper device 59 are provided. That is, FIG.
As shown in FIG. 2, a paper feed start light-shielding plate 71 and a resist start light-shielding plate 72 are provided on the outer wall of the end plate flange on the right rear side of the plate cylinder 1 on the same circumference of the plate cylinder 1. They are attached at intervals. Each shading plate 70, 71
Is made of, for example, a metal plate such as stainless steel or an appropriate synthetic resin, and its tip is formed so as to project to the inner side. On the other hand, on the side of the main body frame near each of the light shielding plates 70, 71, a paper feed starting light shielding plate 71 and a resist starting light shielding plate 72 are mounted facing each other on the same circumference of the plate cylinder 1. The paper feed registration sensor 70 is attached in such a manner that the paper feed registration sensor 70 is selectively sandwiched. Paper feed registration sensor 70
Is a transmissive optical sensor including a light emitting unit and a light receiving unit.

A press roller 21 is disposed in the vicinity of the lower side of the outer peripheral surface of the plate cylinder 1 facing the ink roller 2 so that the press roller 21 can come in contact with and separate from the outer peripheral surface of the plate cylinder 1. The press roller 21 presses the paper 38 against the master 8 on the plate cylinder 1 which has been prepressed.
And a second position apart from the first position (which is also the initial position shown in FIG. 1). Displacement means 29 for displacing the press roller 21 between the first position and the second position is provided at the end of the press roller 21 on the far side as viewed in FIG. The displacement means 29 includes an arm shaft 22a, a pair of press roller arms 22, 22, a pressure arm 23, and a cam follower 2.
4, a pressure spring 25, a cam 26, and the like.

The arm shaft 22a is rotatably supported by a casing side plate (not shown) fixed to the body frame side. The press roller 21 is formed such that its lateral width is substantially the same as the lateral width of the plate cylinder 1, and a press roller shaft 21a is fixedly inserted through the center thereof. Both ends of the press roller shaft 21a are rotatably supported by the other end of a pair of press roller arms 22 and 22, one end of which is fixed to arm shafts 22a arranged on the front side and the back side of the paper surface of FIG. However, when the master 8 on the plate cylinder 1 is pressed against the master 8 through the paper 38, the master 8 is driven to rotate.

The pressure arm 2 is attached to the end of the arm shaft 22a.
One end of 3 is fixed. A cam follower 24 is rotatably held by a shaft at a substantially central portion of the pressure arm 23. At the other end of the pressure arm 23, one end of a pressure spring 25 (tensile spring) for constantly urging the press roller 21 in a direction in which the press roller 21 is pressed against the outer peripheral surface of the plate cylinder 1 is locked. The other end is locked to the housing side plate side. The other end of the pressure arm 23 is biased by the pressure spring 25 in such a direction as to swing clockwise around the arm shaft 22a. The other end of the pressure arm 23 has a notch 23a that can be engaged with a locking claw 60a of a locking member 60 described later.
Are integrally formed and can be engaged with and disengaged from the locking member 60.

On the other hand, a cam shaft 26a, to which a cam 26 that rotates in synchronization with the rotation of the plate cylinder 1 is fixed, is rotatably supported on the housing side plate near the cam follower 24. The cam 26 is, for example, a plate cam having a small diameter portion and a large diameter portion. A belt pulley, a gear or the like (not shown) is fixedly mounted on the cam shaft 26a and is connected to the main motor 20 via a drive transmission means such as a belt and a gear (not shown). It is designed to rotate in synchronization with the rotation of. The cam follower 24 is biased by the pressure spring 25 in such a direction as to always contact the cam 26. Therefore, the pressing drive means for driving the press roller 21 is mainly composed of the main motor 20, the pressure spring 25 and the cam 26.

The pressure arm 23, the cam follower 24, the pressure spring 25, and the cam 26 which constitute the displacement means 29.
1 is not limited to the example in which it is arranged only on the back side of the paper surface of FIG. 1 as described above, and the uniform pressing force of the press roller 21 is applied to the plate cylinder 1.
The press roller arm pair 22, 2 is applied to the outer peripheral surface of the
As in the case of 2, it is of course possible to arrange the same shape and the same phase on the front side of the paper surface of FIG.

In FIG. 1, reference numeral 69 is for holding the press roller 21 at the second position shown in FIG. 1 (strictly, a position slightly further apart than the second position) except when the paper is being passed. The printing pressure releasing means is shown. The printing pressure releasing means 69 includes a locking member 60, a support shaft 61, a solenoid 62 and a tension spring 6.
Mainly consists of 3.

The locking member 60 is swingable around a support shaft 61 planted in the housing side plate, and has the above-mentioned engaging claw 60a integrally formed at one end thereof. There is. At the other end of the locking member 60, one end of a tension spring 63 that urges the engagement claw 60a in a direction to always engage the notch 23a of the pressure arm 23 is formed. The other end of the tension spring 63 is locked to the housing side plate side. A plunger 62a of a solenoid 62 fixedly mounted on the housing side plate is connected to the other end of the locking member 60 on the side opposite to the position where the tension spring 63 is disposed via a pin. The solenoid 62 is a pull type.

As described above, the printing pressure releasing means 69
By turning on the solenoid 62, the displacement means 29
The press roller 21 occupies the first position through a detailed operation described later. by this,
The press roller 21 presses the paper 38 continuously while being driven and rotated by the master 8 on the plate cylinder 1 which has been prepressed. By turning off the solenoid 62 of the printing pressure releasing means 69, the displacing means 29 is deactivated, and the press roller 21 is separated from the first position to the second position (initial position) through a detailed operation described later. ) Occupy. The solenoid 62 is
On / off control is performed by the control means 90 shown in FIG.

The paper feeding device 59 includes a paper feeding tray 37 on which the papers 38 can be unwound so that they can be raised and lowered, and a paper feeding tray 3.
The pair of registration rollers 31, 32 by contacting the sheet 38 on the sheet 7.
The sheet feeding roller 35 and the separating member 36 as a separating and conveying unit that separates and conveys the sheets 38 one by one toward the nip portion of the plate cylinder 1 and the outer peripheral surface of the plate cylinder 1 and the press roller 21 with a timing. It is provided with a pair of registration rollers 31, 32 as a registration means for feeding the paper 38.

The paper feed tray 37 is loaded with paper 38 by a drive device (not shown) equipped with a paper feed tray lifting motor 55, a wire type lifting mechanism, etc., which are schematically shown in FIG.
Of the paper is always pressed against the paper feed roller 35 by a predetermined pressing force (paper 3
8 is contacted with a pressing force capable of being conveyed, that is, the paper 38 is moved up and down while being held in contact with the increase and decrease of the paper 38 with a pressing force within a conveyable range. The paper feed tray 37 has a structure capable of using many kinds of papers and paper sizes, and is suitable for a stencil printing apparatus capable of stacking 500 or more papers with a paper loading capacity of, for example, papers 38 of paper sizes A3 and A4. Have a structure.

In the paper feed tray 37, as shown in FIG.
A pair of side fences 110a and 110b for positioning and aligning both side edges of the sheet 38 according to the sheet size are movably arranged in the sheet width direction Y. FIG. 4 shows a paper size detection mechanism. The paper size detection mechanism determines the paper size of the paper 38 in conjunction with the movement of the pair of side fences 110a and 110b in the paper width direction Y. This paper size detection mechanism includes a pair of movable side fences 110a and 110b, a pinion 116 rotatably attached to and supported by an immovable member arranged below the paper feed tray 37, and a lower portion of the side fence 110a. A rack portion 11 formed on the edge portion and meshing with the pinion 116
5, a rack portion 114 formed at the lower edge of the side fence 110b, which faces the rack portion 115 and meshes with the pinion 116, and the rack portion 1 of the side fence 110b.
14, a shielding portion 114a provided with a plurality of notches protruding downward at the lower end edge portion facing 14 and bent at appropriate intervals, and the immovable member of the paper feed tray 37 are fixed at appropriate intervals. A plurality of (two in this case) lateral size detection sensors 118a and 118b that are respectively provided and selectively engage with the shielding portion 114a, and an appropriate gap in the paper feed direction X in the immovable member of the paper feed tray 37. Vertical fixed size sensor 1 (3 here)
It is mainly composed of 19a, 119b and 119c.

Each lateral size detection sensor 118a, 118b
Is a transmission type optical sensor having a light emitting portion and a light receiving portion, and detects the length and size of the paper 38 in the paper width direction Y by selectively engaging with the shielding portion 114a. Vertical size detection sensors 119a, 119b,
Reference numeral 119c is a reflection type optical sensor. The vertical size detection sensors 119a, 119b, 119c detect the length / size of the paper 38 in the paper feeding direction X. The lateral size detection sensors 118a and 118b and the vertical size detection sensors 119a, 119b and 119c are collectively referred to as a sheet size detection sensor group 89. The paper size detection sensor group 89 is electrically connected to the control means 90 shown in FIG. 6, and the CPU of the control means 90 combines the size signal data detected by these paper size detection sensor groups 89.
The paper size of the paper 38 is determined by the judgment of 91. The paper size detection sensor group 89 has a function / structure as a paper size detection unit that detects the paper size of the paper 38.

The lateral size detection sensor for detecting the length / size of the paper 38 in the paper width direction Y and the paper 3 are provided.
As the vertical size detection sensors for detecting the size in the paper feeding direction X in FIG. 8, there are two and three, respectively, for the sake of simplification of the description. It is preferable. Details of such a paper size detection method include the technology previously proposed by the applicant of the present application and disclosed in, for example, Japanese Patent Application Laid-Open No. 9-30714. The paper size detection method is not limited to the above-described method, and another method, for example, the slider slides in conjunction with the paper feed side plate (side fence), and is arranged according to the paper size. It may detect by contacting / connecting with each terminal of the paper size detecting plate.

As shown in FIG. 3, the paper feed roller 35 is formed integrally with a metal paper feed roller shaft 35a.
One end of the paper feed roller shaft 35a is rotatably supported by the housing side plate. At one end of the paper feed roller shaft 35a,
A toothed feed roller pulley 47 is attached.
Between the paper feed roller shaft 35a and the paper feed roller pulley 47, a one-way clutch for rotating the paper feed roller 35 so that the paper 38 is conveyed only in the paper conveyance direction X, that is, for rotating the paper feed roller 35 only in the clockwise direction ( (Not shown) is provided.

The separating member 36 has a member called a separating pad which is made of rubber or resin having a high friction coefficient with respect to the paper 38 and which can come into contact with the paper feed roller 35. The separation pad is biased by a compression spring (not shown) serving as a biasing means in a direction in which it is pressed against the paper feed roller 35.

As shown in FIGS. 1 and 3, below the paper feed roller pulley 47, there is provided a paper feed motor 45 as a separation / conveyance driving means for rotating the paper feed roller 35 so as to be fixed to the housing side plate. Has been. The sheet feeding motor 45 is, for example, a stepping motor as a motor driven by pulse input, and a toothed sheet feeding motor pulley 46 is fixedly provided on its output shaft. A toothed paper feeding motor belt 48 is stretched between the paper feeding roller pulley 47 and the paper feeding motor pulley 46. As a result, the paper feed roller 3
5 and the paper feed motor 45 are in a rotational driving force transmission relationship with the paper feed motor belt 48 and the one-way clutch.

As shown in FIGS. 1 and 3, the upper registration roller 31 is integrally formed with a metal registration roller shaft 31a, and the lower registration roller 32 is integrally formed with a metal registration roller shaft 32a. Both ends of the registration roller shafts 31a and 32a are rotatably supported by the housing side plate. A toothed registration roller pulley 52 is attached to one end of the lower registration roller shaft 32a. The lower registration roller 32 is movably and rotatably supported by the casing side plate via a registration roller shaft 32a. The upper registration roller 31 is provided so as to come into contact with and separate from the lower registration roller 32 so as to come into contact with the lower registration roller 32 at a predetermined timing. More specifically, the registration roller upper part 31 is synchronized with the rotation of the plate cylinder 1 by a registration roller up-and-down mechanism (not shown) including a registration roller opening / closing cam connected to the main motor 20 and the registration roller lower part 32. (For example, Japanese Patent Application Laid-Open No. 2000-127
(See the registration roller up-and-down mechanism shown in FIG. 10 disclosed in Japanese Patent No. 593).

As shown in FIGS. 1 and 3, below the lower registration roller 32, a registration motor 50 as registration driving means for rotationally driving the pair of registration rollers 31 and 32 is fixedly mounted on the housing side plate. Has been. The registration motor 50 is, for example, a stepping motor as a motor driven by a pulse input, and a registration motor pulley 51 having teeth is fixedly provided on its output shaft. A toothed registration motor belt 53 is stretched between the registration roller pulley 52 and the registration motor pulley 51. As a result, the lower registration roller 32 and the registration motor 50 have a rotational driving force transmission relationship via the registration motor belt 53.

In the paper conveyance path XA from the position where the registration roller pairs 31 and 32 are arranged to the separation conveyance section formed by the paper feed roller 35 and the separation member 36, the leading end of the paper 38 conveyed by the paper feed roller 35 is provided. A first paper sensor 39 as a paper detection means for detecting is provided. The first paper sensor 39 also has a function of detecting that the paper 38 remains in the paper transport path XA on the upstream side of the arrangement position of the first paper sensor 39 (the position where the leading edge of the paper 38 can be detected).

Further, the leading edge of the paper 38 fed from the registration roller pairs 31 and 32 is in the paper conveyance path XA between the plate cylinder 1 and the press roller 21 to the nip portion of the registration roller pairs 31 and 32. A sheet leading edge detecting sensor 41 as a sheet leading edge detecting means for detecting is provided. The sheet leading edge detection sensor 41 is located upstream of the arrangement position of the sheet leading edge detection sensor 41 (position capable of detecting the leading edge of the sheet 38) and at the arrangement position of the first sheet sensor 39 (position capable of detecting the leading edge of the sheet 38). It also has a function of detecting that the paper 38 remains in the paper transport path XA on the downstream side.
The first paper sensor 39 and the paper leading edge detection sensor 41 are
It is a reflection type optical sensor including a light emitting unit and a light receiving unit.

The distance of the paper transport path XA from the position where the first paper sensor 39 is arranged (the position where the leading edge of the paper 38 can be detected) to the center of the nip portion of the paper feed roller 35 is set on the paper feed tray 37. For example, it is set to be at least shorter than the length of a postcard size that can be transported. Therefore, for example, the front end of the postcard is sandwiched by the nip portion of the registration roller pair 31 and 32, and the rear end of the postcard is in a state of being sandwiched between at least the paper feed roller 35 and the separating member 36.

In the vicinity of the downstream side of the printing section formed by pressing the press roller 21 against the outer peripheral surface of the plate cylinder 1, the leading end thereof is close to the outer peripheral surface of the plate cylinder 1 and the plate-making on the plate cylinder 1 is completed. A peeling claw (not shown) for forcibly peeling the sheet 38 from the master 8 is provided. The peeling claw is the plate cylinder 1
The peeling claw displacing means provided with a cam, a spring, and the like, which are driven to rotate in synchronism with the rotation of the plate 3, comes close to the outer peripheral surface of the plate cylinder 1 and the printed sheet 3 is printed from the plate-made master 8 on the plate cylinder 1.
8 is configured to be displaceable between a peeling position forcibly peeling 8 and a non-peeling position that avoids contact with the clamper 7 arrangement portion that is separated from the peeling position and protrudes from the outer peripheral surface of the plate cylinder 1. . In the vicinity of the lower part of the peeling claw, there is arranged a paper discharging and conveying device provided with a porous belt or the like for sucking and adsorbing and carrying the printed paper 38 separated by the peeling claw. On the downstream side of the sheet discharging device in the sheet discharging direction,
Printed paper 38 carried by the above-mentioned paper discharge carrying device
A paper discharge tray (not shown) for discharging and stacking the paper is disposed. A paper discharge sensor 42, which is a reflection type optical sensor for detecting the printed paper 38 separated by the peeling claw, is provided in the paper discharge path between the peeling claw and the paper discharge conveying device. . The peeling claw, the paper discharge conveyance device, and the paper discharge tray constitute the paper discharge device described above.

Next, the detailed configuration of the operation panel 80 will be described with reference to FIG. The operation panel 80 is arranged above the document reading device. On the operation panel 80, from the reading of the image of the original to the plate ejection, plate making, plate feeding, plate printing,
A plate-making start key 81 as an operation starting means for starting a series of steps (operations) up to the sheet discharging step, a ten-key 83 for setting / inputting the number of prints, etc. A print start key 82 for activating a print operation for the number of print sheets set / input), and a skip paper feed print function as a skip paper feed print mode setting means for setting an operation related to a skip paper feed print mode described later. A mode setting key 84 and a speed down key 96a as a printing speed setting means for selectively setting one printing speed from five printing speeds of printing speed levels 1 to 5 as a setting value of the printing speed. And speed up key 9
An LED (light emitting diode) for displaying the set print speed set by the print speed setting key 96 composed of 6b and the speed down key 96a or the speed up key 96b.
A speed indicator 97 composed of a lamp group, a liquid crystal display unit 85 for displaying a message such as an operation state and an operation procedure, a jam location of the master 8 and the paper 38, and the like are arranged.

The liquid crystal display section 85 is driven through a liquid crystal drive circuit or the like, and has a message display section 86 and a picture display section 87. The message display unit 86 and the picture display unit 87 of the liquid crystal display unit 85 perform the conveying operation by the paper feed roller 35 and / or the feeding operation by the registration roller pair 31 and 32 that exceeds the number of repetitions described in the operation described later. At this time, it has a function as a notification unit (subordinately, a display unit) for notifying that the paper 38 is in the jammed state.

The speed indicator 97 is driven via a light emitting diode drive circuit or the like. On the speed indicator 97, the "setting print speed: 3rd speed" with hatching in the center is
A standard printing speed corresponding to a printing speed that is normally used, which is a speed down key 96a or a speed up key 96b.
It is set automatically when is not pressed. Here, for example, the leftmost "set print speed: 1st speed" in FIG. 5 is 60 sheets / mi with the lowest print speed.
n: 60 rpm, "Set print speed: 2nd speed" print speed is 75 sheets / min: 75 rpm, "Set print speed: 3"
"Speed" is a printing speed of 90 sheets / min: 90 rpm, and "Set printing speed: 4th speed" is a printing speed of 105 sheets / min: 1.
The setting print speed: 5th speed on the far right is set to 05 rpm, and the printing speed is set to 120 sheets / min: 120 rpm, which is the highest speed.

The speed indicator 97 is a speed down key 96a.
Alternatively, by pressing the speed up key 96b each time, the printing speed can be switched to five printing speeds from 1 to 5 (hereinafter, simply referred to as "printing speed: 1st speed to 5th speed"). Lights up the speed. Each time the speed down key 96a or the speed up key 96b is pressed,
Printing speed: It also has a function of sequentially switching the lighting of each LED lamp corresponding to any one printing speed from 1st speed to 5th speed, whereby the printing speed selected by the user can be visually confirmed on the speed indicator 97. You can check it.

Further, the operation panel 80 is provided with a paper size setting means 65 for manually setting the paper size and a paper type setting means 73 for manually setting the paper type. The paper size setting means 65 is, in an embodiment, a postcard size setting key 66 for setting a postcard size, and A.
It has an A4 size setting key 67 for setting the A4 size and an A3 size setting key 68 for setting the A3 size. Corresponding to each of the setting keys 66, 67, 68, indicators 66a, 67 which light up and indicate that the paper size has been set.
a and 68a are provided. Paper type setting means 73
Speaking of an embodiment, has a standard paper setting key 74 for setting the standard paper and a rough paper setting key 75 for setting the paper 38 having a rough surface. Reference numeral 76 denotes a double-sided print setting key as a double-sided print setting unit that sets the use of the single-sided printed sheet 38 to perform double-sided printing. Corresponding to the setting keys 74, 75, 76, indicators 74a, 75a, 76 for indicating that the paper type and the like are set.
a is provided. Each display device 66a, 67a, 68
Each of a, 74a, 75a, and 76a is composed of an LED, and lights up when the paper type or the like is set.

The above-mentioned skip paper feed printing mode means that the paper 38 is not carried by the separating and carrying means (the paper feeding roller 35 and the separating member 36) at a predetermined interval while the plate cylinder 1 is rotating, and This is an operation mode in which the displacement means 29 is deactivated. 1 for skip paper feed print mode setting key
When the button is pressed twice, the LED provided therein lights up, thereby indicating that the skip paper feed print mode has been set. When the skip paper feed print mode setting key 84 is pressed once more, the LED is turned off to display that the skip paper feed print mode has been released. The LED in the skip paper feed print mode setting key 84 is not limited to this, and may be provided separately, for example, as the display device 66a or the like.

Next, referring to FIG. 6, the stencil printing machine 100
The main control configuration of will be described. It should be noted that the second paper sensor 40 indicated by a chain double-dashed line in FIG. 6 is shown in FIG. 6 for convenience in distinction from other control components, and is not included in the present embodiment and will be described later. Note that it is used in the example.

In FIG. 6, reference numeral 90 indicates a control means mainly for controlling the paper feeding operation and the printing operation of the stencil printing apparatus 100. The control means 90 includes a CPU 91 (central processing unit), an I / O (input / output) port (not shown), a ROM 92 (read-only storage device), and a RAM 93.
A microcomputer having a (readable / writable storage device), a timer (not shown), and the like, which are connected by a signal bus (not shown), is provided.
As shown in FIG. 1, the control means 90 is provided in the control board arrangement portion in the main body frame.

The CPU 91 of the control means 90 (hereinafter, may be simply referred to as "control means 90" for the sake of simplification of description) has the above-described operation panel 80 via the input port, the sensor input circuit, and the like. The various keys, the paper size setting means 65, and the paper type setting means 73 are electrically connected to each other and receive data signals and ON / OFF signals from the various keys and the setting means 65 and 73. . Further, the control means 90, via the above-mentioned input port, sensor input circuit, etc., the first paper sensor 39, the paper leading edge detection sensor 41, the paper discharge sensor 42, the paper feed registration sensor 70, and the paper type detection means. 88 and a paper size detection sensor group 89, which are electrically connected to each other, and ON / OFF signals and data from the sensors 39, 41, 42, 70, the paper type detection means 88, and the paper size detection sensor group 89. Receive the signal.

The control means 90 controls the liquid crystal display section 85 and various displays of the operation panel 80, the main motor 20, the paper feed motor through the output port, the liquid crystal drive circuit, the motor drive circuit, the solenoid drive circuit and the like. 45, the registration motor 50, the paper feed tray raising / lowering motor 55, and the solenoid 62 are electrically connected to each other, and various command signals are transmitted to the liquid crystal display unit 85, various display devices, and the motors 2 described above.
0, 45, 50, 55 and solenoid 62, respectively.

Note that the paper size setting means 65 and the paper size detection sensor group 89, and the paper type setting means 73 and the paper type detection means 88, respectively, have overlapping functions, and therefore have either one. I will add that I should do.

In this embodiment, the control means 90 has the following control functions. Firstly, the control means 90 causes the paper feed roller 3 to move within a predetermined time from the start of the paper feed motor 45.
The leading edge of the sheet 38 conveyed by the first sheet sensor 3
9 is not detected, the first paper sensor 39
Paper 38 on the paper transport path XA on the upstream side of the arrangement position of
Is determined to remain, the solenoid 62 is turned off to release the printing pressure, and the sheet size setting means 65, the sheet size detecting sensor group 89, the sheet type setting means 73, or the sheet type detecting means 88 is used. Of each output signal, the predetermined number of repetitions, which will be described later, stored in the ROM 92 is selected from the ROM 92, and the sheet feeding motor 45 is controlled so that the sheet feeding roller 35 repeats the conveying operation a predetermined number of times. After that, the main motor 20 is controlled so that the plate cylinder 1 rotates based on the paper edge detection signal from the paper edge detection sensor 41, and the press roller 21 causes the master 38 on the plate cylinder 1 to transfer the paper 38 to the master 8.
It has a function as a control means for controlling the solenoid 62 and the main motor 20 so as to press.

Secondly, the control means 90 controls the paper feed motor 45.
When the leading edge of the paper 38 conveyed by the paper feed roller 35 is detected by the first paper sensor 39 within a predetermined time from the start time of, and within a predetermined time from the start time of the registration motor 50, Registration roller pair 31, 32
When the leading edge of the sheet 38 fed by the sheet is not detected by the sheet leading edge detection sensor 41, the first sheet sensor 3
It is judged that the sheet 38 remains in the sheet conveyance path XA on the downstream side of the arrangement position of 9 and on the upstream side of the arrangement position of the sheet leading edge detection sensor 41, and the solenoid 62 is turned off to release the printing pressure. In addition to the state, the paper size setting means 65 or the paper size detection sensor group 8
9, paper type setting means 73 or paper type detecting means 88
With reference to each output signal from the ROM 92, a predetermined number of times of repetition, which will be described later, stored in the ROM 92 in advance is selected from the ROM 92, and the paper feeding motor 45 is operated so that the paper feeding roller 35 repeats the feeding operation a predetermined number of times of repetition. To control
After the registration motor 50 is controlled so that the pair of registration rollers 31 and 32 repeats the feeding operation a predetermined number of times, based on the paper leading edge detection signal from the paper leading edge detection sensor 41, the main plate cylinder 1 is rotated so as to rotate. In addition to controlling the motor 20, it has a function as a control unit that controls the solenoid 62 and the main motor 20 so that the press roller 21 presses the sheet 38 against the master 8 on the plate cylinder 1.

Thirdly, the control means 90 causes the paper to be fed when the feeding operation by the paper feed roller 35 or the like and / or the feeding operation by the registration roller pair 31, 32 which exceeds the number of repetitions described in the operation described later is performed. It has a function of controlling the message display portion 86 and the picture display portion 87 of the liquid crystal display portion 85 so as to notify and display that the 38 is in the jammed state.

Fourthly, the control means 90 sets a predetermined interval while the plate cylinder 1 is rotating, based on the skip paper feed print mode setting from the skip paper feed print mode setting key 84.
It has a function as plate cylinder idle intermittent feed control means for performing the operation related to the skip feed printing mode in which the feed roller 35 does not convey the paper 38 and the displacement means 29 is deactivated, When the skip paper feed print mode is set, the conveyance speed of the paper 38 by the paper feed roller 35 is set to the plate cylinder 1.
It has a function of controlling the paper feed motor 45 so as to decelerate according to the number of rotations (printing speed).

The ROM 92 conveys the paper to be carried out by the paper feed roller 35 by rotating the paper feed motor 45 in accordance with the paper feed conditions (combination of paper type, paper size, use of single-side printed paper in double-sided printing, etc.). It has a function as a storage unit that stores the number of times the operation is repeated and the number of times the feeding operation is performed by the registration roller pairs 31 and 32 by rotating the registration motor 50. The ROM 92 registers the number of repetitions of the conveyance operation by the paper feed roller 35 for rotationally driving the paper feed motor 45 and the number of repetitions of the feeding operation by the registration roller pairs 31 and 32 according to the paper feed conditions. Relational data for rotationally driving the motor 50 is obtained in advance by experiments or the like, or the programs shown in FIGS. 8 and 9 are stored in advance. Regarding the number of times of repetition stored in the ROM 92 in advance, regarding the paper type, for example, the paper feed roller 35 such as rough paper with a rough surface is used.
If the coefficient of friction against the separating member is relatively high, and the paper size is relatively large, it is possible to find that the paper that has been printed on one side in double-sided printing will not feed or will not feed if it is used for single-sided printing only. It is set to increase the number of jams due to the occurrence of jams.

Further, in the ROM 92, the arrangement position of the first sheet sensor 39 (the front end of the sheet 38) can be detected from the arrangement position of the sheet feeding roller 35 (center of the nip portion with the separating member) by the rotation drive of the sheet feeding motor 45. Position), for a fixed distance of the paper transport path XA, data relating to a predetermined time during which the paper 38 is transported and a predetermined number of pulses supplied to the paper feed motor 45, and rotation of the registration motor 50 to rotate the registration roller pair. Paper conveyance path XA from the arrangement position of 31 and 32 (center of the nip portion) to the arrangement position of the paper edge detection sensor 41 (position where the edge of the paper 38 can be detected)
For a certain distance, the data regarding the predetermined time for which the paper 38 is conveyed and the predetermined number of pulses supplied to the registration motor 50 are stored in advance. Strictly speaking, each of the predetermined times and the number of pulses are determined by the paper feed roller 35 and the separating member according to the paper feed conditions (combination of paper type, paper size, use of single-side printed paper in double-sided printing, etc.). Alternatively, paying attention to the fact that the slip amount of the paper 38 is different between the pair of registration rollers 31 and 32, corresponding to the above-mentioned paper feeding conditions (paper type, paper size, combination of paper used for single-sided printing in double-sided printing, etc.). It is preferable to set in advance by experiments or the like. With respect to the number of repetitions, for example, the related data (data table) may be changed along with the increase of the paper type and the like, so in order to handle such a case, P
ROM (programmable ROM) or ROM92
Of course, it does not matter even if the chip is changed.

The RAM 93 temporarily stores the judgment results and calculation results of the CPU 91, and stores the output signals from the above-mentioned sensors, the above-mentioned setting means and the above-mentioned detecting means, etc. at any time, and inputs / outputs these signals. I do. The timer measures the time from the start of the paper feed motor 45 to the output of the ON signal of the first paper sensor 39, and from the start of the registration motor 50 to the output of the paper leading edge detection sensor 41. It has a function as a timekeeping means. It should be noted that the number of pulses supplied to and input to the motor 45 from the start of the paper feed motor 45 is counted instead of the time counting function of the timer, or the pulse is supplied to the motor 50 from the start of the registration motor 50. The CPU 91 of the control means 90 may be provided with a function as a pulse number counting means for counting the number of generated pulses.

Here, the paper type detection means 88 will be supplementarily described. Specific examples of the sheet type detecting means 88 include, for example, a type that optically detects the intensity of transmitted light to detect the thickness of the sheet 38, and a roller that mechanically measures the sheet thickness. A type in which a gap between them is enlarged to detect with an electric sensor is used.

Next, the operation will be described with reference to FIGS. The operation described below is performed under the control of the control means 90. A user sets a document (not shown) on the document receiving tray of the document reading device, and before and after this, a paper 38 of a paper type and a paper size to be used for printing is appropriately replenished and stacked on the paper feed tray 37. At this time, for example, by pressing the A3 size setting key 68 of the paper size setting means 65 in the operation panel 80, the paper 38 of the paper size A3 is set, or the paper size detection sensor group 89 of the paper feed tray 37 is used to set the paper size. It is assumed that the A3 sheet 38 is automatically detected. Similarly, for example, the standard paper setting key 74 of the paper type setting means 73 on the operation panel 80 is pressed to set the standard paper 38 or the paper type detecting means 88.
Therefore, the standard paper 38 is automatically detected.

When the plate-making start key 81 of the operation panel 80 is pressed, a plate-making start signal is generated and input to the control means 90, whereby a series of operations from plate discharge to sheet discharge are automatically performed. First, the plate making operation is performed in parallel with the plate discharge operation, but before or after this, the paper feed tray elevating motor 55 is turned on to turn on the paper feed tray 37.
The control means 90 indicates that the uppermost sheet 38 comes into contact with the sheet feeding roller 35, and the uppermost sheet 38 is ready to be fed by the ON detection of the sheet feeding position detection sensor (not shown). When the determination is made, the sheet feeding device 59 enters the sheet feeding standby state.

The plate cylinder 1 is rotated by the main motor 20 being driven to rotate, and the used master 8 wound on the plate cylinder 1 is peeled off and discarded by a plate discharge device (not shown). Next, the plate cylinder 1 is stopped by rotating the clamper 7 to the plate feeding position where the clamper 7 is located substantially right side in FIG.

When the plate cylinder 1 is stopped at the plate feeding position, one document is sent to the reading section by the operation of the document separating and conveying device (not shown) provided in the document reading device, and the operation of the scanner (not shown) is performed. The original image is read as optical information by an image sensor, the optical information is converted into an analog electric signal by an image sensor such as a CCD (charge coupled device), and further passed through the A / D converter and the plate making control device. The heating element of the thermal head 11 is energized in a pulse shape in the main scanning direction to selectively generate heat by the digital image signal processed and transmitted, and the stepping motor is rotationally driven. The platen roller 10, the pair of conveying rollers 12 and 12 and the pair of reversing rollers 14 and 14 start to rotate, and the master roll 8
Plate making is performed in which the thermoplastic resin film portion of the master 8 is selectively perforated by heat in accordance with image information while the master 8 is pulled out from a and is transported in the master transport direction X1. From the initial stage of plate making to the plate feeding of the master 8 which has been plate-made to the plate cylinder 1 (described later), the reversing roller pair 1
The electromagnetic clutches 4 and 14 are turned on, and the rotational driving force of the stepping motor is the reverse roller pair 14, 1
4 is in the state of being transmitted.

The leading end of the master 8 is the guide plate 15
Is inserted between the clampers 7 which are guided to the stage 6 and are expanded with respect to the stage 6, and the reversing roller pairs 14, 14 and the like rotate by a predetermined angle, and the stepping motor has a corresponding number of steps. Master 8 that has reached the set value and has been prepressed
When it is determined that the front end of the master 8 has reached between the stage 6 and the clamper 7, the clamper 7 is closed by the opening / closing device, and the front end of the master 8 that has been plate-prepared is sucked between the stage 6 and the clamper 7. Be held.

After clamping the leading end of the plate-making master 8, the plate cylinder 1 restarts to be rotated by the rotation drive of the main motor 20, and the plate-making master 8 turns the reversing roller pair 14, 1.
4 is fed and fed to the outer peripheral surface of the plate cylinder 1 so as to be wound, but when the outer peripheral surface of the plate cylinder 1 is wound, it is performed without causing winding wrinkles. At this time, when the electromagnetic clutch is turned off, the reversing roller pair 14, 14 is rotated by the rotational force of the plate cylinder 1 via the master 8.
Since the master 8 is driven to rotate, an appropriate tension acts on the master 8 to more reliably prevent winding wrinkles from occurring.

When it is judged that the master 8 has completed the plate making and the conveyance of the set amount of the plate-made master 8 by the rotational driving of the stepping motor by the predetermined number of steps, the cutter 13 operates to make the plate-made master. When 8 is cut and the rotation drive of the stepping motor is stopped, the platen roller 10 and the conveying roller pair 12, 1
2 and the pair of reversing rollers 14, 14 stop rotating.

Then, the rear end of the cut master 8 after plate making is pulled out of the plate making device 17 by the rotation of the plate cylinder 1 and completely wound around the outer peripheral surface of the plate cylinder 1. The winding of the master 8 that has been plate-finished on is completed.

When the winding of the plate-making master 8 on the plate cylinder 1 is completed, the plate cylinder 1 starts to rotate in the direction of the arrow shown in FIG. 1 at a predetermined peripheral speed to start the paper feeding / printing process. It Hereinafter, description will be added with reference to the flowcharts of FIGS. 8 and 9 as appropriate. The control means 90 causes the printing pressure releasing means 69 until the leading edge of the sheet 38 crosses / passes the sheet leading edge detection sensor 41, in other words, until the leading edge of the sheet 38 is detected by the sheet leading edge detection sensor 41. Since the solenoid 62 is controlled to remain off, the displacing means 29 is in the non-actuated state, whereby the press roller 21 is held at the second position, that is, the initial position separated from the outer peripheral surface of the plate cylinder 1. ing. For convenience of explanation, regarding the paper feeding / printing / paper discharging operation, a normal operation in which no feeding, jamming, or winding of the paper 38 does not occur will be described first (step S1 of the flowcharts shown in FIGS. 8 and 9). ~ See step S11).

The plate cylinder 1 rotates in the direction of the arrow, and first, as shown in FIG.
The paper feed start light-shielding plate 71 shown in FIG.
By engaging with 0, the paper feed registration sensor 70 is turned on to generate a paper feed start signal, and this signal triggers the paper feed motor 45 to start (start rotation). The paper feed motor 45 is driven to rotate in the clockwise direction in FIG. By rotating in the clockwise direction, the uppermost sheet 38 on the sheet feeding tray 37 that is in contact with the sheet feeding roller 35 is separated into one sheet by the cooperative action of the separating member 36 while being conveyed. The registration roller pair 31, which is the downstream side in the direction X,
It is sent toward the nip portion 32 (see step S1 and step S2).

As shown in FIG. 7, the leading edge of the sheet 38 is normally conveyed toward the nip portion of the registration roller pair 31, 32 by the rotation of the sheet feeding roller 35, that is, the leading edge of the sheet 38 is counted by the timer. Within a predetermined time (or within a predetermined number of pulses supplied to the paper feed motor 45, the description in the parentheses is omitted hereinafter), the first paper sensor 39 detects and the first paper sensor 39 is turned on ( Hereinafter, this signal will be referred to as "on detection", and this signal will be input to the control means 90. Thereafter, based on a command from the control means 90, the paper feed motor 35 rotates for a predetermined number of pulses (a predetermined number of steps) and then stops. At this time, the registration roller upper part 31 descends and comes into contact with the registration roller lower part 32 at a predetermined rotation / timing synchronized with the rotation of the plate cylinder 1 of the registration roller opening / closing cam in the registration roller elevating mechanism. The nip part of is formed.

The paper 38 is fed by a predetermined number of steps from the position detected by the first paper sensor 39 until the paper feed motor 35 stops, so that the paper 39 is nipped at the registration roller pair 31, 32. After the tips of the
The sheet 39 is held in a state in which a predetermined curved flexure is formed at the leading end of the sheet 39.

Here, the fact that the paper 38 is normally conveyed is based on the following. That is, the position where the first paper sensor 39 is arranged (the position where the leading edge of the paper 38 can be detected) from the position where the paper feed roller 35 is arranged (center of the nip portion with the separation member).
Since the distance of the paper transport path XA up to is constant, the rotation speed of the paper feed roller 35 (peripheral speed, in other words, the transport speed of the paper 38) is constant, and the paper 38 is normally transported. Then, the time required for the paper 38 to be conveyed or the number of pulses supplied to the paper feeding motor 45 for the above distance is also within a predetermined time or within the number of pulses (see step S3 and step S4).

Next, the plate cylinder 1 is further rotated in the direction of the arrow in FIG. 1, and the resist starting light-shielding plate 7 shown in FIG.
When the sheet feeding registration sensor 70 is engaged with the sheet feeding registration sensor 70, the sheet feeding registration sensor 70 is turned on to generate a registration start signal, and this signal is used as a trigger to activate the registration motor 50 (start rotation). The registration motor 50 is driven to rotate counterclockwise in FIG. 3, and the lower registration shaft 32a and the lower registration roller 32 rotate counterclockwise via the registration motor pulley 51, the registration motor belt 53, and the registration roller pulley 52. By doing so, the leading edge of the paper 39 that is in contact with and is on standby at the nip portion of the registration roller pair 31, 32 is fed while being pressed by the registration roller 31 and the printing drum 1 and the press cylinder 1 are pressed at a timely timing. It is sent toward the space between the rollers 21 (see step S5 and step S6).

Next, in step S7, the paper 38 fed by the pair of registration rollers 31 and 32 is normally passed, that is, the leading end of the paper 38 is within a predetermined time (or the registration time) measured by the timer. Motor 5
This signal is input to the control means 90 when the sheet leading edge detection sensor 41 detects the ON state within a predetermined number of pulses supplied to 0 (hereinafter, the description in the parentheses is omitted). Then, based on a command from the control means 90, the solenoid 62 of the printing pressure releasing means 69 is energized, and the displacement means 29 is operated by turning on the solenoid 62.

Here, the fact that the paper 38 has been normally fed is based on the following. That is, the registration roller pair 3
Since the distance of the sheet conveyance path XA from the arrangement position of 1 and 32 (center of the nip portion) to the arrangement position of the sheet leading edge detection sensor 41 (position where the leading edge of the sheet 38 can be detected) is constant,
The rotation speed of the registration motor 50 (peripheral speed, in other words, the feeding speed of the paper 38) is kept constant, and the paper 3
8 would have been fed normally, then paper 3
8 time required for feeding or registration motor 5
The number of pulses supplied to 0 is also based on being within a predetermined time or within the number of pulses.

When the solenoid 62 is turned on, the plunger 62a is attracted, whereby the locking member 60 swings counterclockwise around the support shaft 61 against the biasing force of the tension spring 63, and the engaging The notch 23 is formed in the locking claw 60a of the stop member 60.
The other end of the pressure arm 23 that locks a is unlocked and swings clockwise around the arm shaft 22a by the urging force of the pressure spring 25. By the swinging of the pressure arm 23 on the other end side, the outer peripheral surface of the cam follower 24 abuts on the contour peripheral surface of the cam 26, and the outer peripheral surface of the cam follower 24 faces the peripheral surface of the small diameter portion of the cam 26 and is in a non-contact state. At the rotational position of the cam 26, the press roller arm pair 22,
The armature 22 swings clockwise around the arm shaft 22a by the urging force of the pressure spring 25 and ascends. As a result, the outer peripheral surface of the press roller 21 is displaced to the first position where the sheet 38 is pressed against the master 8 on which the plate has been made on the plate cylinder 1, and the press roller 21 is driven to rotate to make the plate on the plate cylinder 1. By continuously pressing the paper 38 against the completed master 8, so-called plate-making printing is performed to bring the plate-made master 8 into close contact with the outer peripheral surface of the plate cylinder 1 and to fill the ink therein. In this stencil printing, stencil printing is performed by the ink bleeding from the opening portion of the opening 1a of the plate cylinder 1 to the perforated portion of the master 8 that has been plate-making and transferred to the surface of the paper 38.

At this time, the ink roller 2 also rotates in the same direction as the rotation direction of the plate cylinder 1. The ink in the ink reservoir 4 is
The ink is adhered to the surface of the ink roller 2 by the rotation of the ink roller 2, the amount of which is regulated when passing through the gap between the ink roller 2 and the doctor roller 3, and is supplied to the inner peripheral surface of the plate cylinder 1. At this time, the upper registration roller 31 rises and separates from the lower registration roller 32 at a predetermined rotation position of the plate cylinder 1 by a predetermined rotation / timing of the registration roller opening / closing cam in the registration roller up / down mechanism. The registration motor 50 is also driven after being rotated by a predetermined number of pulses (a predetermined number of steps) and then stopped.

The plate cylinder 1 rotates in the direction of the arrow in FIG. 1, and the clamper 7 presses the plate cylinder 1 against the plate roller 2.
1, the cam 26, which was rotationally driven in synchronism with the rotation of the plate cylinder 1, has a cam follower 2 on the peripheral surface of the large diameter portion.
Since the press roller 21 is rotated to a position in contact with the outer peripheral surface of the press drum 4, the press roller 21 is separated from the clamper 7 projecting outward from the outer peripheral surface of the plate cylinder 1, and interference between the press roller 21 and the clamper 7 part is avoided. To be

Then, the sheet 38 on which the plate is imprinted / stencil printed
Is further conveyed by the rotation of the plate cylinder 1 in the direction of the arrow in FIG.
When the leading edge of the sheet is detected to be ON by the paper discharge sensor 42, the control unit 90 determines that the sheet has been normally conveyed without being wound up on the plate-making master 8 on the plate cylinder 1 (see steps S8 to S10). .

Paper 38 thus imprinted and stencil printed
The front end of the plate is peeled off from the plate-making master 8 on the plate cylinder 1 by a peeling claw (not shown) approaching the outer peripheral surface of the plate cylinder 1.
The peeled paper 38 is discharged and stacked on the paper discharge tray. On the other hand, from the time when the press roller 21 comes into contact with the outer peripheral surface of the plate cylinder 1, the plate cylinder 1 makes about three-quarters of a round, and when the peripheral surface of the large diameter portion of the cam 26 contacts the cam follower 24, that is, the locking. Locking claw 60a of member 60 and notch 23a of pressure arm 23
When and can be locked, the power supply to the solenoid 62 is cut off by a command from the control means 90. Then,
The locking member 60 is attached to the support shaft 61 by the urging force of the tension spring 63.
Is swung clockwise around the
The notch 23a of the pressure arm 23 is locked to a. As a result, the press roller 21 returns to and is held at the second position (initial position) apart from the outer peripheral surface of the plate cylinder 1, and enters the print standby state.

Further, during the paper feeding or plate-making printing, the platen roller 10, the conveying roller pairs 12, 12 and the reversing roller pairs 14, 14 restart the rotation, and the tip of the cut master 8 is turned by the reversing roller pair 14. , 14 toward the nip portion. Based on the pulse number of the stepping motor, the tip of the cut master 8 is the reverse roller pair 1
When it is judged that it reached the nip part of 4, 4 and was pinched,
The platen roller 10, the pair of conveying rollers 12 and 12, and the pair of reversing rollers 14 and 14 stop rotating, and a plate-making standby state is prepared for the next plate-making.

After the printing on the plate, the user appropriately views the printed matter discharged to the paper discharge tray to determine whether or not the normal printing operation may be performed. When the number of sheets is set and the print start key 82 is pressed, the same paper feeding, normal printing, and paper discharging operations as described above are sequentially performed. Note that the number of the printed sheets 38 is not counted as a normal number of normal prints (see step S11).
The normal printing operation is performed in accordance with the fact that the number of sheets of the printing plate 38 printed as described above is not counted as the normal normal number of printed sheets, as compared with the plate printing operation, and the set printing speed desired by the user. The only difference is that the feeding, printing and discharging operations at speed are performed.

Next, with reference to the flow charts of FIGS. 8 and 9, an abnormal operation of the paper feeding / printing / paper discharging operation in the case of non-feeding, jamming, or winding of the paper 38 will be described.

In the same manner as described above, the operations from step S1 to step S2 are performed, and the leading end of the paper 38 is moved to the registration roller pair 31, by the rotation of the paper feeding roller 35 through the activation of the paper feeding motor 45. When the leading edge of the sheet 38 is not detected by the first sheet sensor 39 within the predetermined time measured by the timer, even though the sheet 38 is conveyed toward the nip portion 32, the control unit 90 When it is determined that the paper 38 remains on the upstream side of the paper transport path XA with respect to the position where the first paper sensor 39 is arranged, the rise of the press roller 21 with the solenoid 62 kept off is locked, that is, the press roller 21 The printing pressure released state in which the second position is maintained is maintained (see step S3 and step S12).

Then, in step S13, it is determined whether the number of repetitions by the paper feeding motor 45 is N times or less. In the example of the first embodiment, as described above, the paper size A3 is used as the paper type and the paper size, and the standard paper 38 is used for printing. Since it is stored and set, it corresponds to the first (0th) time here, so that the answer is YES, and the process proceeds to the first step S1. In step S1, as described above, the plate cylinder 1 is rotated again in the direction of the arrow, and the paper feed start light-shielding plate 71 shown in FIG. When the sensor 70 is turned on, the sheet feeding motor 45 is activated again in step S2 and is driven to rotate in the clockwise direction in FIG. 3, and the sheet feeding roller 35 rotates again in the clockwise direction. Paper 3 that was in contact with and was sent only part way through the paper sensor 39 last time
8 is conveyed toward the nip portion of the pair of registration rollers 31 and 32 while being separated into one sheet again as described above. At this time, the sheet feeding motor 45 is started again in step S2, and the number of repetitions N = 1 is counted and incremented by the control means 90.

In step S3, as shown in FIG. 7, the front end of the paper 38 is conveyed and the paper 38 is detected by the first paper sensor 39 within a predetermined time measured by the timer.
If the tip of the sensor is detected to be on, then the control means 9
Based on the command from 0, the paper feed motor 35 rotates for a predetermined number of pulses (a predetermined number of steps) and then stops (see step S4). At this time, or when the leading edge of the sheet 38 is not detected by the first sheet sensor 39 within the predetermined time, the process proceeds to step S12, and the control unit 90 conveys the sheet beyond the position where the first sheet sensor 39 is arranged. Route X
It is determined that the sheet 38 still remains on the upstream side of A, and the printing pressure released state with the solenoid 62 turned off is maintained. Then, in step S13, it is determined whether or not the number of repetitions N times related to the number of startups of the sheet feeding motor 45 is equal to or less than N times, and the result is YES because it corresponds to the first time here, the process proceeds to the beginning step S1 again, and steps S1 to S3 are performed. The above-described operation / judgment processing is performed.

Thus, in step S3, and when the leading edge of the paper 38 is not detected by the first paper sensor 39 within the predetermined time, the preset number of times the paper feed motor 45 is started in step S13. When the number of repetitions N (= 3) has been exceeded, a jam warning is displayed on the message display section 86 of the operation panel 80 by the command from the control means 90, and the jam is displayed on the picture display section 87. The location is lit or blinked, and at the same time, the rotation drive of the main motor 20 is stopped (see step S14).

The user visually recognizes the jam warning display displayed on the message display unit 86 and the jam occurrence position displayed on the picture display unit 87, and opens the front cover or the like at the place where the paper feeding device 59 is arranged to remove the jammed paper. Perform removal work, etc.
After removing the jammed paper, the process is restarted from step S1.

Next, if the operations from step S1 to step S6 are performed in the same manner as the above-mentioned normal operation,
Alternatively, the number of repetitions N related to the number of times the paper feed motor 45 is activated
When the leading edge of the paper 38 is detected by the first paper sensor 39 within a predetermined time counted by the timer by the conveying operation of less than or equal to the number of times and the subsequent operation is normally performed up to step S6, the following operation is performed. become. That is, when the leading edge of the sheet 38 that should have been fed by the rotation of the pair of registration rollers 31 and 32 is not detected by the sheet leading edge detection sensor 41, there are two cases of the position of the leading edge of the sheet 38. . That is, even though the leading edge of the sheet 38 is detected by the first sheet sensor 39, the sheet 38 has not reached the nip portion of the pair of registration rollers 31, 32, so that the sheet is not fed by the pair of registration rollers 31, 32. In this case, the sheet is fed by the pair of registration rollers 31 and 32, but due to an excessive slip amount in the same nip portion, the sheet is fed to the arrangement position of the sheet leading edge detection sensor 41 (the position where the leading edge of the sheet 38 can be detected). A second case is assumed in which it was not sent. Which of these two cases can be determined unless special detection means or the like is provided for the pair of registration rollers 31 and 32, and hence the same feeding failure will be made without making a distinction.

In the above case, the control means 90 positions the first paper sensor 39 (the position where the leading edge of the paper 38 can be detected).
It is determined that the paper 38 remains on the paper transport path XA on the downstream side and upstream of the arrangement position of the paper front end detection sensor 41 (the position where the front end of the paper 38 can be detected), and the process proceeds to step S12. The printing pressure release state is maintained with the press roller 21 occupying the second position with the solenoid 62 turned off.

Then, in step S13, it is judged whether or not the number of times of repetition by the registration motor 50 is N times or less. Here, since it corresponds to the first time (0 times), the answer is yes, and the process proceeds to the first step S1. In step S1, the paper feed registration sensor 70 is turned on in the same manner as described above, so that the paper feed motor 45 is restarted in step S2 to be driven to rotate clockwise in FIG.
By rotating the paper feed roller 35 in the clockwise direction again,
The paper 38 that was in contact with the paper feed roller 35 and was fed only part way to the paper sensor 39 last time is separated into one again as described above, and the registration roller pair 31, 3
It is conveyed toward the nip portion of 2. Since the leading edge of the paper 38 is detected by the first paper sensor 39, the paper feed motor 45 is instructed by the control means 90 so that the paper feed motor 45 moves above the registration roller 3 by the registration roller up / down mechanism.
In synchronization with the falling timing of 1, the driving is stopped by driving for a predetermined number of pulses.

Next, in step S5, the paper feed registration sensor 70 is turned on to restart the registration motor 50 in the same manner as described above.
Is rotated again in the counterclockwise direction to rotate the lower registration shaft 32a and the lower registration roller 32 in the counterclockwise direction, so that the leading end of the paper 39 located near the nip portion of the registration roller pair 31, 32 is The sheet is fed while being pressed by the registration roller 31 and is sent out between the plate cylinder 1 and the press roller 21 at timing (see steps S5 and S6). At this time, the registration motor 50 is restarted in step S6, and the number of repetitions N = 1 is counted and incremented by the control means 90.

In step S7, if the leading edge of the sheet 38 is not detected to be ON by the sheet leading edge detection sensor 41 within the predetermined time measured by the timer, the process proceeds to step S12, and the control means 90 makes the first Paper sensor 3
The paper is conveyed to the paper conveyance path XA downstream of the arrangement position of 9 (the position where the front end of the paper 38 can be detected) and upstream of the arrangement position of the paper front end detection sensor 41 (the position where the front end of the paper 38 can be detected). When it is determined that the pressure roller 38 is still present, the process proceeds to step S12, and the printing pressure release state is maintained with the press roller 21 occupying the second position with the solenoid 62 off. Then, step S13
In step S1, it is determined whether or not the number of repetitions of the registration motor 50 is equal to or less than N, and here it is the first time, so the answer is YES, the process proceeds to the beginning step S1 again, and the above-described operation / judgment of steps S1 to S6 is performed. Processing is performed.

Thus, in step S7, when the leading edge of the sheet 38 is not detected to be ON by the sheet leading edge detection sensor 41 within the predetermined time, step S13.
When a preset number of repetitions N (= 3) of the number of startups of the paper feed motor 45 is exceeded, a jam warning is displayed on the message display unit 86 of the operation panel 80 by a command from the control unit 90. At the same time, the location of the jam is lit or blinked on the picture display portion 87, and at the same time, the rotational drive of the main motor 20 is stopped.

The user visually recognizes the jam warning display displayed on the message display unit 86 and the jam occurrence position displayed on the picture display unit 87, and opens the front cover or the like at the position where the paper feeding device 59 is arranged to remove the jammed paper. Perform removal work, etc. After removing the jammed paper, the process is restarted from step S1.

Next, if the operations from step S1 to step S7 are performed in the same manner as the above-mentioned normal operation,
Alternatively, the leading edge of the sheet 38 is detected by the sheet leading edge detection sensor 4 within a predetermined time counted by the above-described timer by the feeding operation with the number of times of repetition N times or less related to the activation number of the registration motor 50.
If it is detected in step 1 and the subsequent operation is normally performed up to step S7, in step S8, the printing pressure releasing means 6 is operated based on the command from the control means 90 as described above.
When the solenoid 62 of No. 9 is energized and the solenoid 62 is turned on, the displacing means 29 is actuated, whereby the press roller 21 is displaced to the first position, and the press roller 21 is driven to rotate. Stencil printing is performed by continuously pressing the paper 38 against the master 8 on which the plate has been made.

Next, in step S9, the upper registration roller 31 rises from the lower registration roller 32 at a predetermined rotational position of the plate cylinder 1 and separates from the lower roller 32, and
The registration motor 50 is also driven after being rotated by a predetermined number of pulses (a predetermined number of steps) and then stopped.

Then, the stencil-printed sheet 38 is further conveyed by the rotation of the plate cylinder 1 in the direction of the arrow in FIG. 1 while being pressed by the press roller 21, and the leading edge of the sheet 38 is detected by the sheet ejection sensor 42 as ON. If the leading edge of the printed paper 38 is not detected to be ON by the paper discharge sensor 42 within a predetermined time measured by the timer, it is determined whether or not the master has completed the plate making on the plate cylinder 1. It is judged by the control means 90 that it has been wound up to 8, and step S
Proceed to 15. In step S15, the message display portion 86 of the operation panel 80 is instructed by the control means 90.
The roll-up warning is displayed and the picture display section 8
The location of the winding is lit or blinkingly displayed on 7, and at the same time, the rotational drive of the main motor 20 is stopped.

The user visually recognizes the winding-up warning display displayed on the message display unit 86 and the winding-up occurrence place displayed on the picture display unit 87, and opens the front cover or the like at the place where the plate cylinder 1 is arranged to wind-up. Perform paper removal work. After removing the rolled-up paper, the process is restarted from step S1.

In the above operation example, the paper type A and the paper size are the paper size A3 and the standard paper 3 is used.
Although the example of using 8 for printing has been described, other cases such as "coarse paper", "paper printed on one side" used for double-sided printing, "postcard" or paper 38 of "paper size A4" is used. The difference is that the number of repetitions N is different depending on the combination thereof, and the operation example can be performed extremely easily from the above-described operation example, and therefore the description thereof will be omitted.

The operation when the skip paper feed print mode is set will be briefly described below. Here, for example, a case where the printing operation is performed by feeding the plate cylinder 1 every three rotations will be described. When the skip paper feed print mode setting key 84 on the operation panel 80 is pressed, a signal relating to the skip paper feed print mode setting is input to the control means 90, thereby the key 8
4 is lit to indicate that the skip paper feed print mode has been set.

When the skip paper feed print mode is set in this manner, a print operation is performed by feeding paper every three rotations of the plate cylinder 1 according to a command from the control means 90, and the paper feed roller 3
The paper feed motor 45 is configured to reduce the conveyance speed (feed amount) of the paper 38 by 5 according to the rotation speed (printing speed) of the plate cylinder 1.
Is controlled. As a result, it is possible to feed the paper 38 while separating the paper 38 at a low speed according to the number of revolutions (printing speed) of the plate cylinder 1.

In the stencil printing apparatus 100 shown in FIG. 1, the uppermost sheet 38 stacked on the sheet feed tray 37 is separated into one sheet by the sheet feed roller 35 and the separating member 36 and is conveyed. The trailing edge of the paper 38 is the paper feed roller 3
After the sheet 5 and the separating member 36 have passed through the separating / conveying unit formed so as to face each other, the separating / conveying of the next sheet 38 is started and the sheet is fed. For example, the perimeter of plate cylinder 1 is 500m
In the case of continuously conveying a sheet 38 having a sheet size A3 and a length (vertical size) of 420 mm in m, the trailing end of the sheet 38 fed before (first) is next (rear). The paper 38 is continuously fed with a space of 100 mm from the leading end of the paper 38 fed to the paper. That is, the trailing edge of the preceding sheet 38 is 100 m from the leading edge of the sheet 38 to be conveyed next.
Since it is necessary to complete the next sheet feeding preparation by the distance of m, the higher the speed, the faster the separation operation of the paper 38, etc., and the unstable separation / conveyance operation. there were. As described above, the skip-feed printing mode in the present invention is, rather than obtaining a printed matter faster by high-speed printing, puts top priority on eliminating feeding failure such as non-feeding, feeding error or jam. This is effective in the case of obtaining a printed matter that does not waste 38.

For example, when the plate cylinder 1 is rotating at 60 rpm (set print speed: 1st speed) and the conveyance speed of the paper 38 by the paper feed roller 35 is 300 mm / sec, the plate cylinder 1 is Since the conveyance speed for feeding the paper 38 during three rotations can be reduced to 100 mm / sec, the separation performance of the paper 38 can be improved and slips can be reduced. It is possible to realize more reliable conveyance of the paper 38 by reducing a paper feed error such as a paper error or a jam, and to prevent the paper 38 from being wasted.

As described above, in the first embodiment, it can be said that the printing method according to claim 1 was adopted. In addition,
In the first embodiment, if it is not necessary to obtain the above advantages of the skip paper feed print mode, the skip paper feed print mode setting key 84 (skip paper feed print mode setting means)
The function and the fifth function of the control unit 90 as the plate cylinder idling intermittent paper feeding control unit and the fifth function may not be essential configurations and functions.

(Modification of Embodiment 1) FIGS. 6 and 10
A modified example of the first embodiment is shown in FIG. In this modified example, as compared with the first embodiment, as shown in FIG. 6 and FIG. A second paper sensor 40 (indicated by a chain double-dashed line in FIG. 6) as a paper detection unit provided on the paper conveyance path XA up to the position where the front end can be detected and detecting the front end of the paper 38 conveyed by the paper feed roller 35. ) And control means 90
The main difference is that it has a control means 90 having a fifth function described later in addition to the first to fourth functions.

The second paper sensor 40 is located upstream of the arrangement position (center of the nip portion) of the registration roller pairs 31 and 32, and from the arrangement position of the first paper sensor 39 (position where the leading edge of the paper 38 can be detected). Also has a function of detecting that the paper 38 remains in the paper transport path XA on the downstream side.
The second paper sensor 40 is a reflective optical sensor similar to the first paper sensor 39. Here, the first paper sensor 39
In order to make the relationship between the respective arrangement positions of the second sheet sensor 40 and the second sheet sensor 40 easier to understand more concretely, examples of the respective arrangement dimensions / distances are, for example, a pair of registration rollers 31, 32.
The linear distance from the arrangement position (center of the nip portion) to the separating / conveying portion (center of the nip portion) between the paper feed roller 35 and the separating member 36 is 60 mm, and the linear position from the arrangement position of the registration roller pairs 31 and 32 (center of the nip portion) The linear distance to the arrangement position of the second paper sensor 40 (the position where the leading edge of the paper 38 can be detected) is 10 mm, and the first paper sensor 39 is arranged from the arrangement position of the second paper sensor 40 (the position where the leading edge of paper 38 can be detected). The linear distance to the position (the position where the leading edge of the paper 38 can be detected) is 15 mm.

In addition to the first to fourth functions of the first embodiment, the control means 90 responds to the position of the leading edge of the paper 38 detected by either the first paper sensor 39 or the second paper sensor 40. And has a fifth function of controlling the sheet feeding motor 45 so as to change the conveyance start timing of the sheet feeding roller 35. More specifically exemplifying the fifth function, in the case where the leading edge of the paper 38 conveyed by the paper feed roller 35 is detected by the first paper sensor 39 within a predetermined time from the start of the paper feed motor 45. The predetermined time is the time required for the paper 38 to be conveyed at a predetermined conveyance speed with respect to the distance of the paper conveyance path XA from the arrangement position of the first paper sensor 39 to the arrangement position of the second paper sensor 40. If the leading edge of the sheet 38 is not detected by the second sheet sensor 40 within the time added to the control means 90.
Indicates that the paper 38 remains in the paper transport path XA from the position where the first paper sensor 39 is arranged to the position where the second paper sensor 40 is arranged (jam state or the like), so that the paper 38 remains. The leading edge position of the paper 38 can be detected and determined more accurately than in the first embodiment.

Next, the operation of this modified example will be briefly described, focusing on the points different from the abnormal operation of the first embodiment. For example, to explain with borrowing step S7 shown in FIG. 8, the paper 38 is detected by the paper leading edge detection sensor 41 within a predetermined time measured by the timer of the control means 90.
If the leading edge of the sheet is not detected to be ON, the processing operation of step S12 as described above is performed, the determination processing operation of step S13 is performed, and then the processing operation of step S1 is performed, and then the processing operation of step S2. Is done,
At the time of this re-feeding, there is an advantage that the following operation is executed. That is, at the time of re-feeding, the registration roller upper 31
When the paper feed motor 45 is activated and the leading edge of the paper 38 is set to be inserted into the nip portion of the registration roller pair 31 and 32, the first paper sensor is detected. 39 or the second paper sensor 40 can easily detect the position of the leading edge of the paper 38 remaining in the paper transport path XA, and thus the transport start timing of the paper feed roller 35 (transport start time) of the paper 38 to be inserted. Since the optimum setting can be made according to the position of the leading edge, even though the leading edge of the sheet 38 approaches the nip portion of the registration roller pair 31, 32,
The problem that the front end of the paper 38 starts to be fed quickly and the front end of the paper 38 jumps out to the downstream side from the nip portion of the registration roller pair 31, 32 does not occur.

With the leading edge of the paper 38 protruding toward the downstream side from the nip portion of the registration roller pair 31, 32 in this manner, the registration motor 50 is activated to rotate the registration roller pair 31, 32 to feed the paper 38. In this case, the leading end position of the paper 38 is shifted by the length of the leading end of the paper 38 that has jumped out, and the paper 38 is sent to the nip portion (printing unit) between the plate cylinder 1 and the press roller 21. Although the image position is displaced, this modification can avoid such a problem.

Paper 3 staying in paper transport path XA
If it is desired to detect and judge the leading edge position of 8 more accurately than in the above-described modified example and further prevent the deviation of the print image position at the time of re-feeding more finely and surely, a plurality of ( Not limited to the first paper sensor 39 and the second paper sensor 40 as the two paper detection means, for example, three or more paper detection means are used as the registration roller pairs 31, 3.
It is preferable to provide it on the paper transport path XA between the second position and the position of the paper feed roller 35. As described above, the present invention has been described with respect to the specific embodiments and modified examples or the examples included in these, but the present invention is not limited to the above-mentioned ones, and may be appropriately combined with each other. It is obvious to those skilled in the art that various embodiments and examples may be configured according to their needs and purposes / applications within the scope of the present invention.

[0129]

As described above, according to the present invention,
A novel printing method and printing apparatus can be provided by solving the problems of the conventional printing method and printing apparatus as described above. The effects of each claim are as follows. According to the first aspect of the present invention, for example, when a sheet having a high friction coefficient with respect to the separating / conveying means or the resisting means or a sheet that easily slips is conveyed or fed, the sheet is not sent to a predetermined time machine, and the resisting means is used. When a sheet remains in the sheet conveyance path from the separation conveyance means to the separation conveyance means, the conveyance operation by the separation conveyance means and / or the feeding operation by the registration means is repeated a plurality of times. It is possible to greatly reduce the time and labor required for jam processing and to automatically perform the printing operation by the plate cylinder and pressing means after the leading edge of the paper fed from the registration means is detected. In addition, since it is configured to discharge while printing, the paper is not wasted.

According to the second aspect of the present invention, for example, at the time of starting the separation / conveyance driving means at the time of conveying or feeding a paper having a high friction coefficient with respect to the separation / conveying means or the registration means, or a paper in which slip easily occurs. Within a predetermined time from
When the leading edge of the sheet conveyed by the separating / conveying section is not detected by the sheet detecting section, or within the predetermined time from the activation of the registration driving section, the leading edge of the sheet fed by the registration section is detected by the sheet leading edge detection section. If not, the control unit determines that the sheet remains in the sheet conveyance path, and the separation conveyance drive unit and / or the registration unit performs a plurality of feeding operations so that the separation conveyance unit repeats the conveyance operation a plurality of times. Since the registration driving means is controlled so as to be repeated once, it is possible to greatly reduce the time and the processing time at the time of jam processing such as paper misfeed or jam processing, and the control means After the control, the plate cylinder driving means is controlled so that the plate cylinder rotates based on the paper edge detection signal from the paper edge detection means, and Since the pressing drive unit is controlled so that the pressing unit presses the sheet relatively to the master on the plate cylinder, the sheet is discharged while printing, so that the sheet is not wasted.

According to the third aspect of the invention, the control means changes the conveyance start timing of the separation conveyance means in accordance with the position of the leading edge of the sheet detected by any of the plurality of sheet detection means. By controlling the separation / conveyance driving means, the position of the leading edge of the sheet retained in the paper conveyance path is detected by any of the plurality of sheet detection means, and the separation / conveying means is optimized according to the position of the leading edge of the sheet. In addition to the effect of the invention described in claim 2, for example, the leading edge of the sheet jumps out to the downstream side from the nip portion of the registration unit, and the registration driving is performed in this state, in addition to the effect of the invention of claim 2. When the registration means is driven by the activation of the means and the leading edge of the sheet is fed,
It is possible to prevent the print image position from being deviated by that amount due to the leading end position of the paper being shifted by the length of the leading end of the ejected paper and being sent to the printing unit.

According to the fourth aspect of the present invention, the control means causes the separating and conveying means to carry out the conveying operation and / or the conveying operation according to the sheet type, the sheet size, and the sheet feeding conditions such as the use of the one-side printed sheet in the double-sided printing. By selecting the number of repeats according to the sheet feeding condition from the storage unit that stores the number of repeats of the feeding operation by the registration unit, the optimum number of repeats of the transport operation and / or the feeding operation according to the sheet feeding condition is selected. Since it is possible to set, the conveyance operation and / or the feeding operation will not be unnecessarily repeated, and conversely, jamming due to a small number of repetitions will not occur. The effect of the invention described in 3 is more reliably exhibited.

According to the fifth aspect of the invention, as for the type of paper, the higher the coefficient of friction with respect to the separating / conveying means is, and the larger the size of the paper is, the more easily the single-sided printing is performed in the double-sided printing. Since the number of repeats of the transport operation and / or the feeding operation is set to be larger when using, the above-mentioned easiness of paper feeding error such as paper non-feeding and jam occurrence according to specific paper feeding conditions are described above. The effect of the invention according to claim 4 is exhibited by being reflected in the number of repetitions.

According to the sixth aspect of the invention, since the notifying means informs that the paper is in the jam state when the carrying operation and / or the feeding operation exceeding the number of repetitions are performed, In addition to the effect of the invention described in any one of 2 to 5, the user can surely know the necessity of jam processing in a timely manner.

According to the seventh aspect of the present invention, the control means skips the separation conveying means so that the sheet is not conveyed at a predetermined interval while the plate cylinder is rotating, and the displacing means is inactivated. 3. When the paper feed printing mode is set, the separation drive means is controlled so as to reduce the speed at which the paper is conveyed by the separation conveyance means in accordance with the number of revolutions of the plate cylinder.
In addition to the effect of the invention described in any one of 1 to 6, since the sheet can be fed while being separated at a low speed by the separation driving unit in accordance with the rotation speed (printing speed) of the plate cylinder 1, It is possible to improve the paper separation performance and reduce slips, which in turn reduces paper feed defects such as misfeeds, paper feed mistakes, and jams, and ensures reliable paper transport, as well as paper waste. There is no need to do it.

According to the invention described in claim 8, the predetermined time is automatically measured by the time measuring means.
In addition to the effect of the invention described in any one of 1 to 7, whether the leading edge of the sheet detected by the sheet detecting unit or the sheet leading edge detecting unit is sent by a normal feeding / feeding operation, or a feeding error occurs. It is possible to accurately and surely judge whether or not there is a jam condition.

According to the invention described in claim 9, the predetermined time corresponds to a predetermined number of pulses input to the separation / conveyance driving means or the resist driving means, so that one of the second to seventh aspects is achieved. In addition to the effect of the invention described in (1), it is possible to relatively easily count the number of pulses as compared with the case of measuring a predetermined time. Normal tip transport
It is possible to accurately and surely determine whether the sheet has been fed by the feeding operation, or whether there is a feeding error or a jam.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional front view of a main part of a stencil printing apparatus showing a first embodiment of the present invention.

FIG. 2 is an example of arrangement of a paper feed start light-shielding plate and a resist start light-shielding plate for detecting the rotational position of the plate cylinder on the end plate of the plate cylinder and the paper feed registration sensor in Embodiment 1 and the like. It is a perspective view which shows an engagement state.

FIG. 3 is a front view of essential parts showing a drive mechanism on a sheet feeding roller and a registration roller in the first embodiment and the like.

FIG. 4 is a perspective view of essential parts showing a paper size detection mechanism arranged in a paper feed tray according to the first embodiment and the like.

FIG. 5 is a plan view of a main part of the operation panel according to the first embodiment and the like.

FIG. 6 is a block diagram showing a control configuration according to the first embodiment and the like.

FIG. 7 is a partial cross-sectional front view of an essential part showing a sheet conveying operation according to the first exemplary embodiment.

FIG. 8 is a flowchart showing an operation sequence of main parts in the first embodiment.

FIG. 9 is a continuation of the flowchart of FIG.

FIG. 10 is a partial cross-sectional front view of a main part of a stencil printing machine showing a modified example of the first embodiment.

[Explanation of symbols]

1 plate cylinder 2 ink roller 8 master 17 plate making apparatus 20 main motor 21 as plate cylinder driving means and pressing drive means press roller 29 as pressing means 29 displacement means 31, 32 registration roller pair 35 as registration means 35 separating and conveying means Paper feed roller 36 Separation member constituting separation / conveyance means 37 Paper feed tray 38 as paper feed base 38 Paper 39 First paper sensor 40 as paper detection means Second paper sensor 41 as paper detection means 41 As paper tip detection means Paper leading edge detection sensor 42 paper discharge sensor 45 paper feed motor 50 as separation / conveyance drive means registration motor 59 as registration drive means 59 paper feed device 62 solenoid 65 constituting paper pressure release means paper size setting means 69 print pressure release means 73 paper type setting means 80 operation panel 84 skip paper feed printing mode Skip feed printing mode setting key 85 as a setting means 85 Liquid crystal display unit 88 as a notifying means Paper type detecting means 89 Paper size detecting sensor group 90 as a paper size detecting means 90 Control means as a plate cylinder idle intermittent feeding control means 91 CPU constituting control means 92 ROM as storage means 100 Stencil printer as an example of printer X Paper transport direction XA Paper transport path

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3F049 AA10 DA11 DA12 LA06 LB03                 3F102 AA13 AB01 BA02 BB02 CA05                       CB01 DA08                 3F343 FB05 FC10 GA02 GB01 GC01                       GD01 HB01 HC05 HD16 JA02                       MA14 MA15 MA54 MA55 MB14                       MB15 MC10

Claims (9)

[Claims] 1. A plate cylinder around which a master made by plate making is wound, a pressing means for relatively pressing a sheet against the master on the plate cylinder, and a sheet with a timing between the plate cylinder and the pressing means. Means for feeding the sheet, a paper feed table for stacking the paper sheets in a payout manner, and a separating and conveying means for contacting the paper sheets on the paper table and separating and conveying the paper sheets one by one toward the registration means. In a printing method using a printing apparatus having, when a sheet remains in a sheet conveyance path from the registration means to the separation conveyance means, the conveyance operation by the separation conveyance means and / or the feeding operation by the registration means is performed. Printing characterized in that the printing operation by the plate cylinder and the pressing means is automatically performed after the leading edge of the paper fed from the registration means is detected repeatedly a plurality of times. Law. 2. A plate cylinder around which a master made by plate making is wound, a plate cylinder drive means for rotating and driving the plate cylinder, a pressing means for relatively pressing a sheet against the master on the plate cylinder, and this pressing means. A pressing drive means for driving the sheet, a registration means for feeding the sheet at a timing between the plate cylinder and the pressing means, and a registration drive means for driving the registration means.
A paper feed table for stacking sheets so that the paper can be fed out, a separation conveyance means for contacting the paper on the paper feed table and separating and conveying the sheets one by one toward the registration means, and driving the separation conveyance means. In the printing apparatus including the separation / conveyance driving means, the paper detection means is provided in the paper conveyance path from the registration means to the separation / conveyance means, and detects the leading edge of the paper conveyed from the separation / conveyance means; Paper leading edge detecting means for detecting the leading edge of the sheet fed from the registering means, which is provided in the sheet transporting path from the cylinder and the pressing means to the registering means, and a predetermined time from the start time of the separating and conveying drive means. Within the time of
When the leading edge of the sheet conveyed by the separating / conveying section is not detected by the sheet detecting section or within a predetermined time from the activation of the registration driving section, the leading edge of the sheet fed by the registration section is changed to the sheet. When it is not detected by the leading edge detecting means, it is determined that the sheet remains in the sheet conveying path, and the separating and conveying driving means and / or the registering means are arranged so that the separating and conveying means repeats the conveying operation a plurality of times. After controlling the resist driving means to repeat the feeding operation a plurality of times,
Based on the sheet leading edge detection signal from the sheet leading edge detecting means, the plate cylinder driving means is controlled so that the plate drum rotates, and the pressing means relatively presses the sheet against the master on the plate cylinder. And a control unit for controlling the pressing drive unit as described above. 3. The printing apparatus according to claim 2, wherein a plurality of the paper detecting means are provided, and the control means positions the leading edge of the paper detected by any one of the plurality of paper detecting means. According to the above, the separation / conveyance drive means is controlled so as to change the conveyance start timing of the separation / conveyance means. 4. The printing apparatus according to claim 2, wherein the feeding operation and the paper feeding operation are performed in accordance with a paper type, a paper size, a paper feed condition such as use of a paper printed on one side in double-sided printing.
/ Or a printing apparatus, which has a storage unit for storing the number of repetitions of the feeding operation, and the control unit selects the number of repetitions according to the sheet feeding condition from the storage unit. 5. The printing apparatus according to claim 4, wherein the paper type has a relatively high friction coefficient with respect to the separating / conveying means, and the paper size has a relatively large coefficient in the double-sided printing rather than the single-sided printing. A printing apparatus characterized in that the number of times of repetition is set to be larger when a sheet having one side printed is used. 6. The printing apparatus according to claim 2, wherein the sheet is in a jam state when the carrying operation and / or the feeding operation exceeding the number of repetitions are performed. A printing apparatus having an informing unit for informing. 7. The printing apparatus according to claim 2, wherein the pressing means includes a first position for relatively pressing a sheet against a master on the plate cylinder, and the first position. Second away from
And a separating means for displacing the pressing means between the first position and the second position, and the separating and conveying means at a predetermined interval during rotation of the plate cylinder. And a sheet cylinder idle intermittent feeding control means for performing an operation related to the skip feeding print mode for deactivating the displacing means without causing the sheet to be conveyed. At this time, the control means controls the separation driving means so as to reduce the speed at which the sheet is conveyed by the separation conveying means in accordance with the number of rotations of the plate cylinder. 8. The printing device according to claim 2, further comprising a time measuring unit that measures the predetermined time. 9. The printing apparatus according to claim 2, wherein the separation / conveyance driving unit and the registration driving unit are
A printer driven by a pulse input, wherein the predetermined time corresponds to a predetermined number of pulses input to the separation / conveyance driving unit or the registration driving unit.