JPH11170484A - Sheet surface wiping apparatus for printing sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly moisten a wiping sheet of a printing sheet. SOLUTION: A liquid is supplied to a gauge member 17 by a liquid supply means 18 and absorbed. The member 17 has properties for absorbing and oozing the liquid. The liquid is supplied to the member 17 while bringing the member 17 into contact with wiping sheets 3, 19. The liquid is uniformly soaked into the sheets 3, 19. The sheets 3, 19 are brought into contact with a surface of a traveling printing sheet 2 by an urging means 12. The sheets 3, 19 uniformly moisten the printing sheet while wiping paper chips or the like from a surface of the printing sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper wiping device for removing dirt and foreign matter such as paper dust from the surface of printing paper.

[0002]

2. Description of the Related Art In order to improve printability, there is a case where a paper surface of a printing paper is wiped to remove paper dust or the like before printing.
As a paper wiping device for performing such an operation, a device disclosed in Japanese Patent Publication No. 8-11441 has been proposed. This is done by wiping the surface of the printing paper by opposing the diaphragm to the printing paper, interposing a cloth between them, spraying water from nozzles to wet the cloth, expanding the diaphragm and pressing the cloth against the printing paper. It is like this.

[0003] Japanese Patent Publication No. 2540277 discloses a paper wiping machine for printing paper, in which a pressing roller having a chromium plating on its surface is opposed to the printing paper, and a hydrophilic wiping sheet is interposed between the two. Water is sprayed on the surface of the pressing roller. The water supplied to the surface of the pressing roller spreads as a thin uniform film on the pressing roller, soaks into the wiping sheet, and adheres to the printing paper. This water-soaked wiping sheet wipes paper dust and the like off the surface of the printing paper.

A paper wiping device disclosed in Japanese Patent Application Laid-Open No. Hei 7-256682 discloses a paper wiping device in which a pressing roller having a chromium plating on its surface is opposed to a printing paper, a hydrophilic wiping sheet is interposed between the two, and the wiping sheet is pressed from a watercraft. Water is supplied to the surface of the roller. The water adhering to the surface of the pressing roller spreads as a thin uniform film with the rotation of the pressing roller, adheres to the wiping sheet, soaks, and then adheres to the printing paper. The water-absorbing wiping sheet wipes paper dust and the like from the surface of the printing paper.

[0005]

However, in the paper wiping device disclosed in Japanese Patent Publication No. Hei 8-11441, water is supplied from the nozzle toward the cloth, so that the wetness of the cloth tends to be uneven in the width direction. Not only does the degree of paper dust removal vary in the width direction of the paper surface, but also the degree of wetness of the printing paper varies in the width direction. Further, it is necessary to change the supply amount of water in accordance with a change in the traveling speed of the printing paper. However, such control is extremely difficult in a conventional method of spraying water from a nozzle onto a cloth. Therefore, there is a problem that the print quality is deteriorated.

[0006] Japanese Patent No. 2540277, JP-A-7-25
The paper surface wiping device of No. 6862 has a problem that the device becomes expensive because it uses a chrome plating roller.
Further, the paper wiping device disclosed in Japanese Patent Application Laid-Open No. Hei 7-256962 has a problem that a large installation space is required because a watercraft is used.

Accordingly, the present invention provides a paper wiping apparatus capable of uniformly removing paper dust and the like while applying a wiping sheet uniformly moistened without using a chrome plating roller or a watercraft. The purpose is to:

[0008]

In order to achieve the above-mentioned object, the invention according to the first aspect is directed to a wiping sheet (2) which comes into contact with the surface of a running printing paper (2) at a speed difference and which can absorb and exude liquid. 3, 19) and the wiping sheet (3, 19) while being in contact with the wiping sheet (3, 19).
19) a contact member (17, 21, 22, 25, 27) capable of absorbing and exuding a liquid to supply a liquid, and a liquid supplied from the corresponding member (17, 21, 22, 25, 27). Pressing means (12, 2) for pressing the absorbed wiping sheets (3, 19) against the surface of the printing paper (2).
0) and the contact members (17, 21, 22, 25, 2)
7) a liquid supply means (18, 2) for supplying and absorbing the liquid.
3, 24, 26, 29) is adopted.

Further, according to the invention of claim 2, the pressing means (12, 20) is arranged such that the pressing member (17, 21, 22,
25, 27) and corresponding members (17, 21, 2)
2, 25, 27) through the wiping sheet (3,
The printing paper wiping apparatus according to claim 1, wherein the liquid is supplied to the printing paper (19) and the wiping sheet (3, 19) is pressed against the printing paper (2).

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1 A paper wiping device for a printing paper is installed between a paper feeding unit and a printing unit of a web printing device, and left and right fixed frames of the paper wiping device are attached to left and right frames of the printing device. 1 is provided as shown in FIG.

Two guide rollers 1a and 1b are stretched between the left and right fixed frames so as to be parallel to various rollers of the printing apparatus, and come into contact with both sides of the printing paper 2, respectively.
The printing paper 2 travels in the direction of the arrow at a speed of, for example, about 200 to 600 m / min while being in contact with the guide rollers 1a and 1b, reaches the printing unit of the printing apparatus, and is subjected to printing.

A wiping sheet 3 for wiping the surface of the printing paper 2 passing between the two guide rollers 1a and 1b is in contact with one surface side of the printing paper 2. The wiping sheet 3 is in the form of a band, and a feeding roll 4 and a collecting roll 5 for winding and collecting the wiping sheet 3 fed from the wiping sheet 3 are supported between left and right fixed frames via support shafts 6 and 7. ing. The two rolls 4 and 5 are detachable from the support shafts 6 and 7, respectively. The support shaft 6 of the feeding roll 4 is supported by a fixed frame via a friction clutch (not shown). Although not shown, the power of the motor is transmitted to the collection roll 5 via a sprocket wheel, a chain, a friction clutch, and the like, and is driven in the direction of the arrow.

While the wiping sheet 3 is moving from the feeding roll 4 to the collecting roll 5, the driving roller 8 for feeding the wiping sheet 3 from the feeding roll 4, the pressing roller 9 in contact with the driving roller 8, and the printing paper 2 are contacted. An idler roller 10 that guides the later wiping sheet 3 to the collection roll 5 is provided. Although not shown, the drive roller 8 rotates intermittently, for example, when an arm fixed to the shaft end thereof is reciprocally driven by an air cylinder, and feeds the wiping sheet 3 little by little from the feeding roll 4 to the collection roll 5. It has become. The press roller 9 is constantly urged toward the drive roller 8 by a spring or the like (not shown) interposed between the arm 11 supporting the press roller 9 and the fixed frame.

With such a mechanism, the wiping sheet 3 is sandwiched between the driving roller 8 and the pressing roller 9 and stretched with a constant tension between the collecting roll 5 and is fed out by a fixed length by the rotation of the driving roller 8. It is sent from the roll 4 to the collection roll 5. In addition, while the drive roller 8 is stopped, the input portion of the recovery roll 5 to the support shaft 7 idles at the position of the friction clutch, so that the recovery roll 5 wipes the wiping sheet 3 with a certain amount of force. Always pull to prevent loosening.

The wiping sheet 4 is made of, for example, a non-woven fabric that can absorb liquid such as water and can ooze out. As will be described later, the wiping sheet 3 comes into contact with the surface of the printing paper 3 in a state where the wiping sheet 3 contains an appropriate amount and uniformly of water supplied from a nozzle serving as a liquid supply unit, and wipes paper dust and the like. Further, the wiping sheet 3 can be formed in a mesh shape, in which case foreign matter such as paper dust can be taken into the mesh. As the nonwoven fabric, for example, a cellulosic material can be used. Instead of a nonwoven fabric, a cotton cloth, a cold gauze or the like can be used.

A pressing member 12 is disposed between the driving roller 8 and the idler roller 10 as means for pressing the wiping sheet 3 against the surface of the printing paper 2. The pressing member 12 slightly moves between the rollers 1a and 1b toward the opposite side of the printing paper 2 so that the wiping sheet 3 can be pressed with an appropriate force against the printing paper 2 traveling between the guide rollers 1a and 1b. I'm stuck. The pressing member 12 is fixed to a distal end of an arm 14 that is rotatable around a support shaft 13 held by a fixed frame, and is provided by an air cylinder (not shown) interposed between the arm 14 and the fixed frame. It is pivotable. When the arm 14 rotates to the position indicated by the solid line, the pressing member 12 moves the wiping sheet 3.
Is pressed against the printing paper 2 and rotated to the dashed line position, the pressing member 12 causes the wiping sheet 3 to move the printing paper 2
Away from

In order to surely reciprocate the arm 14 between the solid line position and the chain line position, a projection 15 is provided on the boss portion of the arm 14, and stoppers 16a and 16b of the projection 15 are fixed to the fixed frame. It is mounted so that the position can be adjusted.

The pressing member 12 is a pressing body having a curved surface at a position facing the wiping sheet 3, and is formed, for example, in a semi-cylindrical shape. The curved surface of the pressing member 12 is covered with the contact member 17. The contact member 17, like the wiping sheet 3, is made of a material capable of absorbing a liquid such as water and exuding. For example,
A cloth roughly knitted with nylon yarn or the like can be used. Both the pressing member 12 and the contact member 17 extend in the width direction of the wiping sheet 3 so as to wipe the printing paper 2 over its entire width.

Above the contact member 17, a contact member 1 is provided.
A nozzle 18 serving as a means for supplying a liquid such as water to 7 is provided. A plurality of nozzles 18 are arranged at a constant pitch along the width direction so that water can be supplied to the wiping sheet 3 as uniformly as possible. Nozzle 1
8 can be swung in the left-right direction in FIG. 1 as needed to disperse the jet water. In that case, water can be supplied to the contact member 17 more uniformly.

The wiping sheet 3 is provided on the other surface of the printing paper 2 between the guide rollers 1a and 1b.
Another wiping sheet 19 for wiping the other surface is in contact with a portion deviating from the contact portion of FIG. Since the wiping sheet 19 is supplied in the same manner as on the one surface side of the printing paper 2, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted.

In such a paper surface wiping device, the water supplied from the nozzle 18 permeates the contact member 17 above the contact portion between the contact member 17 and the wiping sheet 3, and the water supplied from the contact member 17 at the contact portion. The wiping sheet 3 uniformly oozes out and penetrates over substantially the entire width of the wiping sheet 3. The printing paper 2 is uniformly rubbed by the wiping sheet 3 soaked with water, so that paper dust and the like are evenly removed and wet. On the other hand, the wiping sheet 3 adsorbs paper dust and the like on the surface of the printing paper 2 via the permeated water. The paper powder or the like becomes mud-like with water, is captured in the mesh of the wiping sheet 3, and is conveyed to the collection roll 5. The paper dust and the like wiped off by the wiping sheet 3 are taken into the mesh and collected together with the wiping sheet 3.

The wiping of the printing paper 2 by the wiping sheet 3 also plays a role of improving the printing register accuracy. That is, the take-up sheet, which is the printing sheet 2, usually has a water content of about 5%, and as it is unwound, absorbs moisture in the outside air and gradually elongates with the passage of time. In the case of offset printing, for example, black,
When the red, indigo, and yellow colors are sequentially printed, the dampening solution adheres to the printing paper 2 sequentially in each color unit, and the printing paper 2 gradually expands in combination with the absorption of moisture in the outside air. For this reason, color misregistration occurs and the print quality deteriorates. In the present invention, water is applied to the printing paper 2 before reaching the printing section,
Since the printing paper 2 can be brought into the equilibrium state in advance, it is possible to prevent the printing register from being out of order.

The above-mentioned paper wiping device is a printing paper 2
Can be arranged only on one side of the sheet. However, when the sheet is arranged on both sides of the printing sheet 2, curling of the printing sheet 2 when offset printing is performed only on one side of the printing sheet 2 is prevented. Can be prevented. That is, the dampening solution adheres to the printing surface side of the printing paper 2 and swells, and the dampening water does not adhere to the opposite surface side and does not swell, so that the printing paper 2 curls. By applying water from the paper wiping device to the non-printing side of the
If the front and back surfaces are swelled to the same extent, curling can be prevented.

Next, the operation of the paper wiping device will be described.

When the printing apparatus is started, a liquid such as water is supplied to the contact member 17 from the nozzle 18 and the printing paper 2 starts running. When the printing paper 2 rises to a predetermined running speed, for example, about 50 m / min, the pressing member 12 Is rotated to the solid line position, and the wiping sheet 3 is pressed against the printing paper 2.

By making the amount of water discharged from the nozzles 18 variable according to the traveling speed of the printing paper 2, the amount of adhered water can be kept constant regardless of the traveling speed of the printing paper 2. it can.

When the wiping sheets 3 and 19 are pressed against the printing paper 2, the surface of the printing paper 2 is wiped with the wiping sheets 3 and 19, and foreign matters such as paper powder adhering to the surfaces are absorbed and removed. Also, it can be given a moderate amount of water.

Thereafter, the printing paper 2 reaches the printing section of the printing apparatus and is printed.

When the speed of the printing paper 2 is reduced or stopped due to interruption of printing or the like, the contact member 17 and the wiping sheets 3 and 19 are operated by operating the air cylinder.
From the surface of the printing paper 2 to cut off the water supply,
It is also possible to prevent breakage of the printing paper 2 and excessive moistening of the wiping sheets 3 and 19.

When printing is performed only on one side of the printing paper 2, only one pressing member 12 or the like can be operated.

Second Embodiment As shown in FIG. 2, unlike the first embodiment, the pressing member 20 of the paper wiping device of the second embodiment is different from the first embodiment.
Is formed in a columnar shape, and a contact member 21 is wound around the entire circumference.

The pressing member 20 may be fixed so as not to rotate with respect to the arm 14, or may be rotatably supported. When it is made rotatable, it can be made to rotate with the wiping sheet 19 by frictional force.

In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals.

Third Embodiment As shown in FIGS. 3 and 4, unlike the first embodiment, in the paper wiping device of the third embodiment, the contact member 22 also serves as the pressing member in the first embodiment. And a liquid supply means integrally provided.

That is, the contact member 22 has a cylindrical body 23 which is a liquid conduit supported by the arm 14. A nozzle 24 formed of a small hole, a slit, or the like is provided at a position of the cylindrical body
Are provided. And the nozzle 2 of the cylindrical body 23
The location where many 4 are provided is covered with the contact member 22. The contact member 22 has a substantially semi-cylindrical shape, and extends along the width direction of the wiping sheets 3 and 19 and the printing paper 2. The contact member 22 is made of a material obtained by solidifying elastic and porous microfibers in a sponge shape (for example, an Exaine-based composite structural material manufactured by TORAY), a hard sponge, or the like.

In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals.

In such a paper wiping apparatus, the water pressure-fed into the cylinder 23 is supplied from the nozzle 24 to the contact member 2.
2 and soaks out uniformly from the surface of the contact member 22 and uniformly penetrates the contact portions with the wiping sheets 3 and 19 over substantially the entire width of the wiping sheets 3 and 19. The printing paper 2 is rubbed by the wiping sheets 3 and 19 in which the water soaks uniformly, so that the paper dust and the like are evenly removed and the water is evenly absorbed. On the other hand, the wiping sheets 3 and 19 adsorb paper dust and the like on the surface of the printing paper 2 via the permeated water.
The paper powder becomes mud-like containing water, and the wiping sheet 3,
It is caught in the mesh of 19 and is carried to the collection roll 5. The paper dust and the like wiped by the wiping sheets 3 and 19 are collected together with the wiping sheets 3 and 19.

Fourth Embodiment As shown in FIGS. 5 and 6, unlike the third embodiment, in the paper wiping device of the fourth embodiment, a contact member 25 also serving as a pressing member is formed in a cylindrical shape. Correspondingly, a cylindrical body 26 as a liquid conduit penetrates through the member.

The contact member 25 may be fixed so as not to rotate with respect to the arm 14, or may be rotatably supported.

In this embodiment, the same components as those in the first and third embodiments are denoted by the same reference numerals.

Fifth Embodiment As shown in FIGS. 7 and 8, unlike the first to fourth embodiments, in the paper wiping apparatus of the fifth embodiment, the contact member 27 and the liquid supply means are used for wiping. Rollers 28 that rotate while contacting the sheets 3 and 19 are integrally formed. The roller 28 is disposed on the upstream side of a position where the upper pressing member 12 contacts the wiping sheets 3 and 19.

As shown in FIG. 8, the roller 28 has at its center a cylindrical shaft 29 which is a liquid conduit.
The cylindrical shaft 29 is supported by a fixed frame of the paper wiping device via a rotary joint (not shown), and is supplied with water or the like from a liquid supply source. A large number of nozzles 24 including small holes, slits, and the like are provided on the cylindrical wall of the cylindrical shaft 29. The outer periphery of the cylindrical shaft 29 is covered with a contact member 27 from above the opening of the nozzle 24. The contact member 27 is made of a material obtained by solidifying elastic and porous microfibers in a sponge shape (for example, an exine-based composite structural material manufactured by TORAY), a hard sponge, or the like.

The pressing member 12 includes the wiping sheet 3,
This is a pressing body having a curved surface at a position facing 19 and is formed, for example, in a semi-cylindrical shape. The curved surface of the pressing member 12 may be covered with the contact member 17 as in the first embodiment, or may be a metal surface, a synthetic resin surface, or the like.

In such a paper wiping apparatus, a liquid such as water, which is fed into the cylindrical shaft 29 of the roller 28, permeates into the contact member 27 through the nozzle 24 of the cylindrical shaft 29. The liquid permeated into the contact member 27 is
Is in contact with the wiping sheets 3 and 19,
It is transferred to the wiping sheets 3 and 19 and uniformly penetrates substantially the entire width of the wiping sheets 3 and 19. The wiping sheets 3 and 19 wet by the liquid impregnation are pressed against the printing paper 2 by the pressing member 12. The printing paper 2 is composed of the wiping sheet 3, which is uniformly impregnated with water,
By being rubbed with 19, paper dust and the like are evenly removed and wet evenly. The wiping sheets 3 and 19 adsorb paper dust and the like on the surface of the printing paper 2 through the permeated water. The paper powder or the like becomes mud-like containing water, is captured in the mesh of the wiping sheets 3 and 19, and is conveyed to the collection roll 5. Wiping sheet 3, 19
The paper dust and the like wiped in the step are taken into the mesh and collected together with the wiping sheets 3 and 19.

Sixth Embodiment As shown in FIG. 9, unlike the fifth embodiment, the pressing member 20 of the paper wiping device of the sixth embodiment is formed in a columnar shape as in the second embodiment. I have. The contact member 21 may be wound around the surface of the pressing member 20, or the pressing member 20 such as a metal surface or a synthetic resin surface may be used.
May be exposed.

The pressing member 20 may be fixed so as not to rotate with respect to the arm 14, or may be rotatably supported.

In this embodiment, the same components as those in the first and fifth embodiments are denoted by the same reference numerals.

[0049]

According to the present invention, the liquid such as water is once soaked into the wiping member uniformly, and then the liquid is more uniformly applied to the wiping sheet while the contacting member is in contact with the wiping sheet. Since the soaked and uniformly moistened wiping sheet is pressed against the printing paper by the pressing means, paper dust and the like can be appropriately removed from the surface of the printing paper made of recycled paper or the like, and the printability can be improved. In addition, the printing paper has a uniform wetness in the width direction, and the printing quality is improved.

[Brief description of the drawings]

FIG. 1 is a schematic side view illustrating a paper wiping device according to a first embodiment of the present invention.

FIG. 2 is a schematic side view showing a second embodiment.

FIG. 3 is a schematic side view showing a third embodiment.

FIG. 4 is a vertical sectional view of a pressing member according to a third embodiment.

FIG. 5 is a schematic side view showing a fourth embodiment.

FIG. 6 is a vertical sectional view of a pressing member according to a fourth embodiment.

FIG. 7 is a schematic side view showing a fifth embodiment.

FIG. 8 is a vertical sectional view of a contact member according to a fifth embodiment.

FIG. 9 is a schematic side view showing a sixth embodiment.

[Explanation of symbols]

 2: Printing paper 3, 19: Wiping sheet 17, 21, 22, 25, 27 ... Contact member 12, 20 ... Pressing member 18, 24 ... Nozzle 23, 26 ... Cylindrical body 29 ... Cylindrical shaft

Claims (2)

[Claims] 1. A wiping sheet capable of absorbing and exuding liquid and coming into contact with a surface of a running printing paper at a speed difference, and supplying a liquid to the wiping sheet while being in contact with the wiping sheet. A contact member that presses the wiping sheet, which has absorbed the liquid supplied from the member, onto the surface of the printing paper, and a liquid supply unit that supplies and absorbs the liquid to the contact member. An apparatus for wiping printing paper, comprising: 2. The apparatus according to claim 1, wherein said pressing means holds said contact member, supplies liquid to said wiping sheet via a corresponding member, and presses said wiping sheet against printing paper. 2. A paper wiping device for printing paper according to claim 1.