JPH06595B2 - Electronic copying machine - Google Patents

Description

The present invention relates to an electrophotographic apparatus, and more particularly to a desk-top office copying apparatus.

[Conventional technology]

Electronic copiers are widely used as office copiers.
However, electronic copiers have not been fully satisfactory as office copiers. The main reasons are as follows.

(1) Desktop type, easy to use, no high performance. Although there are copiers with high performance, that is, a copy image is clear and has a high copying speed, they are large in size.

There is a liquid developing type as a small desktop type, but it is difficult to obtain a high copying speed.

(2) In addition to the drawback that the copying speed is slow as described above, the liquid developing type is inconvenient for maintenance such as replenishment and replacement of the developer.

(3) The reliability is low. In particular, paper jams are likely to occur, and paper jam handling is troublesome.

[Problems to be Solved by the Invention]

An object of the present invention is to solve the above-mentioned drawbacks of the conventional electronic copying machine and to provide an electronic copying apparatus which is small in size, high in performance, highly reliable, and easy to use.

The above-mentioned purpose is a. Original plate that forms the upper surface of the copier b. A drum-shaped photoconductor disposed below the platen, rotatable and having a seamless photoconductive surface; c. A charging means disposed near and above the photoconductor to uniformly charge the photoconductor; d. Exposure means for performing scanning exposure by forming an optical path parallel to the document table and an optical path bent obliquely downward from the parallel optical path to the photoconductor, and performing scanning exposure; A dry developing means disposed near and near the photoreceptor, f. Transfer means disposed near and below the photoconductor; Separating means disposed near and below the photoreceptor, h. A cleaning means disposed near the photoconductor and between the separating means and the charging means; Transfer paper feeding means for sending the transfer paper to the transfer position in synchronization with the exposing means, Heat roller fixing type fixing means, and le. A transfer paper path forming means for forming a transfer paper path between the separating means and the fixing means, supporting the transfer means and the separating means, and swinging the transfer paper path; The transfer means, the separating means, the transfer paper path forming means and the fixing means are arranged such that the path of the transfer paper passing through these means is linear, and the fixing is performed from the transfer position on the transfer paper path. The heating roller and the pressure roller are configured such that the length up to the means is shorter than the maximum length of the transfer paper used, and the heating roller of the fixing means is closer to the paper discharge side than the pressure roller. An electronic copying apparatus is characterized in that a swinging space of the transfer paper passage forming means is formed below the transfer paper passage forming means.

〔Example〕

 Hereinafter, the present invention will be described with reference to examples.

FIG. 1 shows an electrophotographic copying machine of a movable platen type. 1 in the figure
Indicates the entire device, and 2 indicates the bottom plate. Reference numeral 3 is a front door, which can be rotated with a lower portion as a fulcrum by a known method. Reference numeral 4 denotes a left side cover 400, an exhaust hole, and 5 a rear surface cover.
As shown in FIG. 2, the right side surface cover 4'is provided on the opposite side of the left side surface cover 4. Reference numeral 6 is a document table, 7 is a platen cover, and 8 is a handle for opening and closing the plantain cover. Reference numeral 800 indicates that when the handle 8 is rotated in the arrow direction, the platen car is stopped at a predetermined position.
It is a column provided in association with the control member 801 fixed to the document placing table 6 and the handle 8 so as to maintain the open state.

Reference numeral 9 indicates a copyable state, a state in which the transfer paper has become zero, a paper jam state, and the like, and a numeric keyboard for setting the number of copies, and a means for displaying the numeric keyboard, a clear key, or the like is provided. It is an operation unit having an area 900 for displaying and an area 901 for arranging a copy button.

Although not shown in the figure, the display means based on the pressing of the ten-key pad enables display of up to 99 sheets. Of course, the set number can be changed even during the copying operation. Further, the copy button selects a bias voltage value to be applied to the known magnetic brush type developing device 39 depending on the density of the document to be copied, color or black and white, and the like, so that a high quality image can always be obtained. It is divided into three parts. Reference numeral 10 shown at a position separated from the operation portion 9 is a main switch. 11
Is a cassette for storing A3, B4, A4, B5, B6 and the like.

12 indicates a tray. The front door 3, the rear cover 5, the left and right side covers 4, 4 ', etc. are fixed to the bottom plate 2 by welding to form a plate-like frame F (F') (third part).
As shown in the figure, the frame is arranged parallel to the front side and the back side in FIG. ) Is not relevant to explain. The reason why the frame is welded is, as described above, in consideration of backlash generated when it is fixed to the bottom plate 2 with screws, or mechanical strength.

FIG. 2 is a sectional view of an electronic copying apparatus which is an embodiment of the present invention. This embodiment is a copy table moving type copy machine, and the copy table 6 is provided on the upper part of the copy machine so as to be reciprocally movable left and right.

Reference numeral 13 is a photosensitive drum, which can be rotated as indicated by an arrow. Around the photosensitive drum, parts for executing the electrophotographic process are arranged. That is, the charging device 3 is provided above the photosensitive drum.
8. Near the right side of the photosensitive drum, a magnetic brush type developing device 39,
A transfer device 83, a separating device 84 are arranged below the photosensitive drum, and a cleaning device 90 is arranged on the left side of the photosensitive drum. The exposure device is mainly composed of an exposure lamp 23, a first mirror 25, a lens L, and a second mirror 29, is bent by a horizontal optical path O and a second mirror, and travels obliquely downward to the left toward the photosensitive drum. Have.

The transfer paper is stored in the cassette 11 and is the first paper feed roller.
The sheet is supplied to the transfer position through the second sheet feeding roller 57 and the second sheet feeding roller 80, and is ejected to the tray 12 through the conveying unit 82 that forms the sheet path for the sheet and the fixing device 87. The transfer paper path from the second paper feed roller 80 to the fixing device 87 is a substantially horizontal straight line as shown in the figure.

In FIG. 3, reference numeral 13 is a seamless (commonly known as receptive) photosensitive drum formed by depositing a photoconductive insulating layer made of selenium tellurium on the surface of a hollow aluminum cylinder, and rotates in the direction of the arrow during operation. As can be seen, it is directly connected to the main motor M.

As shown briefly in FIG. 3, the photosensitive drum is held on SH-1 which extends through a frame F'arranged on the back side (right side in the drawing) of the apparatus. Reference numeral 14 is a bearing provided on the frame F'to hold the drum shaft SH-1 rotatably. Reference numeral 15 is a gear provided coaxially.

The drum shaft SH-1 is directly connected to the main motor.

Reference numeral 16 denotes an arm that holds one side of the drum shaft SH-1, and one end of itself is fixed to a frame F provided on the front side (left side in the drawing) of the apparatus. The screw 17 is the stopper. Reference numeral 18 is a pin having a function of establishing a connection between the photosensitive drum 13 and the shaft SH-1 and imparting a rotational force to the drum during a copy operation. As a matter of course, the rim portion 1300 of the photosensitive drum 13 is provided with a groove that can be engaged with the pin 18.

As described above, it will be understood that the photosensitive drum 13 is detachable from the drum shaft SH-1. The axis S
A female screw is cut on the arm 16 side of H-1. This is to prevent damage to the surface of the photosensitive drum when mounting the photosensitive drum 13 on the shaft SH-1 or removing it from the shaft, or to prevent damage to the members arranged in the vicinity thereof. It is for engaging the auxiliary rod 19 so as to fulfill the guide function. Reference numeral G denotes an original placing surface made of transparent glass provided on the original placing table 6 and below the platen cover 7.

The document placing table 6 is controlled to be reciprocable by a known method. It should be noted that the moving distance of the document placing table 6 during the forward movement (during exposure scanning) can be changed according to the size of the transfer sheet to be used. The travel distance regulation signal is transmitted by a plurality of microswitches MS-1, MS-2 and MS-3 that operate in association with the cassette 11.
(See FIG. 5a) Each transfer paper size detection signal is defined.

Most of the process operations of the device are controlled by a microcomputer (not shown), so that the signal will select one of several control programs that can be stored in the microcomputer. The instruction to each process by the microcomputer is based on the phase detection disk 20 attached on the shaft SH-1 holding the photosensitive drum 13, as shown in FIG. That is, a number of slits 2000 are engraved around the phase detection disc 20, and when the disc rotates in accordance with an operation, the number of passages of the slit is set to, for example, a light emitting diode which is a light emitting element.
21 and the phototransistor 22 as a light receiving element (see FIG. 4B) are used for counting, and each process is sequentially controlled according to the count number.

Although the number of the slits 2000 was set to 180 in the implementation, it is needless to say that the number is not limited to this. Reference numeral 23 is an exposure lamp provided below the document mounting table 6 and made of a fluorescent lamp.

The inner surface of the frame 24 is shaped so that the light emitted from the exposure lamp 23 can be focused on the document mounting surface G. A slit hole is formed in the inner surface 2400 of the frame body 24 protruding between the two exposure lamps 23. The reason why the protruding portion is provided in this manner is to prevent diffused reflection light (miscellaneous light) from entering the optical system.

A support plate (not shown) of the first mirror 25 and the frame body 24 are attached so that they can move integrally in the left-right direction during assembly.

Fine adjustment of focus is done with screw 28. L is a lens, 29 is a second mirror, 30 is the second mirror, and
It is a support plate that functions to prevent the intrusion of light. 31
Is a lower plate located below the optical system including the first mirror 25 including the exposure lamp, the lens L, and the second mirror 29, and has an opening 3100 in part. 32 is an upper plate and 33 is a side plate.

From the above, it is necessary not to prevent the light reflected from the original C from the light from the exposure lamp 23 from being guided onto the photosensitive drum 13.
It can be seen that the optical system is shielded from the outside by the upper plate 32, the lower plate 31, the side plate 33, and the support plate 30.

When the original C to be copied is placed on the original placing surface G and the copy button is started by pressing the print button (not shown) selected by the copy number setting and the original, the original placing table 6 is moved to the left side in the drawing. Start moving. The surface of the photosensitive drum 13 is charged by the wire electrode W under the relative movement state. When the document on the document mounting surface G comes to the upper side of the exposure lamp 23, the reflected light from the document C caused by the light emission of the exposure lamp 23 is reflected by the first mirror 25, the lens L and the second mirror 29.
The photosensitive drum is continuously irradiated with light through the slit box 34. Therefore, the charged charges on the photosensitive drum 13 applied before that time are appropriately eliminated or reduced, and are sequentially converted into a charge pattern corresponding to the original C. The number of slits 2000 of the phase detecting disk 20 that is at the same time as the photosensitive drum 13 and has the same rotation speed is counted by the light emitting diode 21 and the phototransistor 22. The count gives the microcomputer instructions to start or stop each process,
The controllable structure is as described above. Therefore, when the leading edge of the electrostatic charge latent image formed on the photosensitive drum reaches the position of the developing device 39, the developing device is activated and the electrostatic latent image is formed. To visualize.

Next, the paper feeding device 56 and the cassette 11 are shown in FIGS.
It will be described with reference to the drawings.

5a is a plan view of the sheet feeding device including a partial cutout, FIGS. 5b and c are left side views of the cam lever 61 in a lowered state and a raised state, and FIG. 5d is a vertical sectional view showing an internal mechanism. .

5a, only the functions of the members that are considered necessary are shown, and the details will be described with reference to FIGS. In the figure, 5600 and 5600 'indicate the left and right side plates, respectively. The sheet feeding device 56 in the embodiment employs a method in which the sheet feeding roller 57 is at a fixed position and the transfer sheet P rises as the transfer sheet decreases. 5601 is a mounting table on which the cassette 11 can be mounted as shown in FIG.
Have 02.

At the side edge and the front edge, as shown in FIG.
03, 5603 'and 5604 are provided. MS-1 is a micro switch for detecting the presence or absence of the transfer paper stored in the loaded cassette 11, and is rotatably attached to the both side plates 5600 and 5600 'so as to be located above the central portion of the mounting table 5601. It is fixed to the shaft SH-4 which is held. Prescription table 5601
Micro switches MS-2 and MS-3 are provided on the lower side of each of the actuators a2 and a3.
It is positioned so as to project from a part of 5602 above the mounting table 5601. It is the cassette that drives the actuator. That is, a part of the cassette 11 corresponding to the size of the transfer paper is provided with a part for urging at least one of the actuators a2 and a3 of the microswitches MS-2 and MS-3 when the cassette is loaded on the mounting table. It is provided.

The plurality of micro switches are micro switches MS
Assuming that the -1 actuator a1 is energized, the following five types of transfer paper sizes can be detected by the combination of the microswitches MS-2 and MS-3.

As described above, the microcomputer performs control according to the transfer paper size in response to the transfer paper size detection signal. Of course, if necessary, the transfer paper size display means can be configured to be activated by the detection signal. Reference numeral 57 is a paper feed roller fixedly mounted on a shaft SH-5 which is rotatably held between the side plates. Also,
A worm wheel 58 is mounted on the right side of the shaft SH-5 and meshes with a worm wheel 59 provided on the output shaft of the paper feeding motor M1 which operates in synchronization with the copy operation. . Reference numeral 60 denotes a crimping plate provided on the rotating shaft SH-6, which is located above the center of the front end portion of the mounting table 5601 and has a shaft SH.
The cam lever 61 is interlocked via -6. Also, the tip is divided into left and right with a notch 6000 in between. When the cam lever 61 is pushed up (FIG. 7C), the tip of the crimping plate 60 is placed on the mounting table 5601 as shown by a chain line in FIG.
Maintained in a first position that is approximately parallel to. This position is a position where the cassette 11 can be engaged (inserted) with the space formed by the bottom flat surface portion 1107 of the cassette and the sheet receiving plate 62 when the cassette 11 is slid on the mounting table 5601. In addition, the crimping plate 60 is a leg 1104 provided on the bottom of the cassette 11.
However, when the detection protrusion 65 projecting from the other hole 5605 provided in the mounting table 5601 is pushed down during the sliding, the second position raised by the mechanical movement through the rotation shaft SH-6. Maintained at. In this state, the pressure bonding plate 60 raises the sheet receiving plate 62 in the cassette 11 so that the uppermost sheet of the accumulated transfer paper P stored in the cassette c is the paper feed roller 57.
Is pressed against.

The detection protrusion 65 is provided as follows. That is, the fifth
Referring to FIGS. A and d, the side plate 5600 and the substantially U-shaped holding member 66 fixed to the side plate 5600 rotatably support the rotation pin 67, and the rotation pin 67 is rotatably supported on the pin 67. An arm 68 is fixedly provided, and a detection protrusion 65 is rotatably provided on a lateral pin 69 planted on the arm 68. Then, the detection protrusion 65 is controlled by the spring 70 in the clockwise direction in FIG. 5D and brought into contact with the arm 68. Therefore, when the detection protrusion 65 is pushed down by the leg portion 1104 of the cassette 11 which is slid to the loading position, the arm 68 is rotated via the locking portion, whereby the rotation pin 67 is rotated, which will be described later. Thus, the lock of the raised position of the cam lever 61 is released. But the cassette 11 that retreats
The leg portion 1104 simply rotates the detection element 65 against the spring 70, the arm 68 and the pin 67 do not operate, and the detection protrusion 65 returns after the leg portion 1104 has passed. Next, the interlocking relationship will be described with reference to FIGS. The cassettes are omitted in FIGS.

Now, 61 is a cam lever as described above, which can be rotated up and down with the pin 71 planted on the outer surface of the side plate 5600 as a fulcrum. 72 is a pin implanted on the side plate 5600 similarly to the pin 71, and is located in the recess 6100 of the cam lever 61 so that the maximum rotation amount (corner) of the cam lever 61 can be regulated. That is, the cam lever 61 is always urged in the clockwise direction by the biasing force of the spring SP-1 stretched between the end of the lower arm 7300 of the bifurcated lever 73 and the pin 74 provided on the side plate 5600. However, the pin 72 is the lower end face of the recess 6100 of the cam lever 61 so as to stop the cam lever 61 at a predetermined position.
It comes in contact with the 6101. Further, when the cam lever 61 is rotated counterclockwise, it comes into contact with the upper end surface 6102 of the recess 6100 of the cam lever 61 in order to regulate the amount of rotation in that direction. As described above, the cam surface 6103 of the cam lever 61 is in contact with the roller element 75 rotatably provided on the upper arm 7301 of the bifurcated lever 73, which is restrained counterclockwise by the spring SP-1. As described above, the cam lever 61 always exerts a clockwise force. The bifurcated lever 73 is a rotating shaft SH to which the crimping plate 60 is fixed.
Therefore, when the cam lever 61 is pushed up so as to rotate counterclockwise from the state shown in FIG. 6B, the bifurcated lever 73 is rotated clockwise against the spring SP-1 and is rotated. The moving shaft SH-6 rotates and the crimping plate 60 descends to its first position. On the contrary, when the cam lever 61 is rotated and lowered in the clockwise direction toward the state shown in FIG. 7C, the bifurcated lever 73 is rotated counterclockwise by the force of the spring SP-1, and the rotation shaft SH-
6 also rotates accordingly, so that the crimping plate 60 rises and is maintained in its second position. In consideration of noise or wear, the pin 72, the lower end surface 6101 of the recess 6100 of the cam lever 61, and the roller element 75 are covered with a ring-shaped or plate-shaped material made of an appropriate resin. A lever 76, which is seen to partially overlap with the forked lever 73 in FIG. 6B, is located between the side plate 5600 and the cam lever 61, and this lever 76 is rotatably held between the side plates 5600 and 5600 '. It is fixedly installed on 7.
The cam lever 61 is normally in non-contact with the cam lever 61, and when the cam lever 61 is rotated counterclockwise as shown in FIG. Is engaged with the bent portion 6104 located at, and thereafter rotated clockwise until the upper end surface 6102 of the recess 6100 of the cam lever 61 contacts the pin 72. The shaft SH-7 is located below the shaft SH-6 having the pressure plate 60, and a lock claw 77 for locking the inserted cassette 11 is provided on the shaft SH-7. The lock claw
In the state in which the cam lever 61 is lowered as shown in FIG. B, 77 is a cutout from the mounting base 5601 by a predetermined amount as shown in FIG.
It projects upward through 5602. Therefore, the cam lever
From the middle of the pushing-up operation of 61, the lever 76 rotates clockwise through the interlocking lever 76 and sequentially retracts to the lower side of the mounting surface 5601. Therefore, the lever 76 moves the cam lever 61 by the amount of rotation necessary to retract the lock claw 77 to a level below the upper surface of the mounting table 5601.
It should be understood that it can be rotated by
Therefore, it should be understood that depending on the relationship between the lock claw 77 and the mounting table 5601, the cam lever 61 can be interlocked from the initial stage of rotation. The lock pawl 77 is controlled in the clockwise direction, that is, in the protruding direction by the other end of a spring 78 which is disposed on the shaft SH-7 and whose one end is locked to the shaft SH-6, as shown in FIG. However, one end is formed with a tip portion 7701 that comes into contact with the lower surface of the mounting table 5601, so that it cannot be rotated (raised) more than necessary. This d
In a portion 7700 projecting from the mounting table 5601 in the state shown in the figure, a front end face 7701 and two stages of lock engaging step portions 7702, 7703 facing rearward are formed. This will be described in the explanation of cassette loading. Reference numeral 78 denotes a locking member that is rotatably provided on a pin 79 that is planted on the side plate 5600 and that locks the cam lever 61. The locking member 78 is bent at the ends of the two arms (bent to the front side in the figure).
It has 7800 and 7801. On the lower bent portion 7801,
The first actuating lever the free end of the l ₁ was allowed secured on pivot pins 67 which are rotated via the sensing projections 65 are engaged. On the other hand, a second actuating lever ₁₂ is provided on a rotatable shaft SH-4 for fixing the microswitch MS-1.
The free end of the second actuating lever l ₂ is engaged on the cam lever 6107. Then are brought interposed tension spring SP-2 between the lower side bent portion 7801 and the second actuating lever l ₂ of the locking member 78. As is apparent from this, when the cam lever 61 descends and the pin 72 prevents further rotation in the clockwise direction, the spring SP-2 moves the locking member 78 in the clockwise direction as shown in FIG. It has a function to prevent the rotation of. The locking member 49, which is positioned at the predetermined position by the spring SP-2, causes the detection protrusion 65 to be projected onto the mounting table 5601 via the pivot pin 67 and the arm 68. It means that it holds l ₁ . At this time, the locking member
The upper bent portion 7800 of 78 is not in contact with the cam lever 61. With this structure, when the cam lever 61 is rotated counterclockwise, the second actuating lever ₁₂ is pushed up by the bent portion 6107 of the cam lever against the biasing force of the spring SP-2. As for the first operating lever ₁₁ and the locking member 78, the protruding portion (folded portion) 6800 of the arm 68 provided integrally with the first operating lever via the pin 67 contacts the lower surface of the mounting table 5601. Therefore, its position does not change. When the cam surface 6105 of the cam lever 61 comes into contact with the upper side bent portion 7800 of the locking member 78, the locking member 78 is moved in a slightly clockwise direction. When the locking surface 6106 extending inward comes above the bent portion 7800, it is returned to the initial position by the action of the spring SP-2. On the other hand, the spring SP-2 acts to pull the free end of the second actuating lever l ₂ downward, so that the cam surface
If the turning force to the cam lever 61 is lost when 6106 passes over the bent portion 7800, a part of the bent portion 7800 will be locked with the locking surface 6106.

Axis SH-4 is given a rotational force clockwise direction via the second actuating lever l ₂ as described above, thus the micro switch MS-1 also rotates to detect the presence or absence of the transfer sheet. As a result, the actuator a1 is moved up to the position shown by the chain line in FIG. A micro switch MS-4 having a transfer paper detecting function is disposed in front of the paper feed roller 57.
The microswitch MS-4 and the actuator of the microswitch SM-1, that is, a4 and a1 are coil winding springs made of thin metal wires. Of course, this may be a conventional rigid body. In the micro switch MS-4, the leading edge of the transfer sheet fed by the sheet feeding roller 57 comes into contact with the conveying roller (second sheet feeding roller) 80 which is still stopped at that time, and then continues. Since a loop is sequentially drawn by the operation of the paper roller 57, the loop is detected by the actuator a4 and electrically connected so as to deactivate the paper feed motor M1.

Reference numerals 81 and 81 'denote guide members, which have a curved portion 8100 on the transfer paper inlet side of the lower guide member 81 for easily forming a loop. The actuator a4 of the micro switch MS-4 for loop detection extends above the curved portion 8100. The upper guide plate 81 'has the function that the loop of the transfer paper is related to the detection by the microswitch MS-4. A notch is provided at a corresponding position of the upper guide plate 81 'so as not to prevent the actuator a4 from being lifted by the increasing loop of the transfer sheet during operation. Reference numeral 80 is a first conveying roller in which the lower roller 80A is connected to an appropriate drive system. 8000 is a spring arranged so that the upper and lower rollers 80A and 80B contact each other with an appropriate pressure.

The first transport rollers 80 are side plates 5600 and 56 of the sheet feeding device 56.
As shown in the drawing, it is arranged at one end of 00 '. The two rollers 80A and 80B have their respective shafts SH-
8 and SH-8 ', a plurality of elastic members (rubber) are arranged with a gap. In addition, the lower roller 80
A lever 8001 is attached to both ends of the shaft SH-8 of A so that the lower part of the shaft can project from the side plate (left side in FIG. D) at a position related to the shaft of the upper roller 80B. There is. A cam portion 8002 is formed on the upper portion of the lever. Further, the lever 8001 is urged clockwise by a spring 8003 with the shaft SH-8 as a fulcrum. This is to prevent the cam portion 8002 from contacting the upper roller shaft SH-8 'during a normal copy operation. or,
The lever 8001 is attached here because, when a paper jam occurs in the vicinity of the lever 8001, a part of the transporting means U configured to pivotally drop (shown by an arrow) with one end as a fulcrum is used finally. In addition, a gap is formed between the rollers to facilitate the discharge.

The transport unit U will be described later.

Next, the cassette 11 will be described with reference to FIGS. 5d and 6. The cassette 11 is made of resin and has a front notch 1100, a rear notch 1101, a left notch 1102, a right notch 1102, and a right notch.
It consists of 1103 and bottom wall 1106.

The portion of the cassette that directly contacts the upper surface of the mounting table 5601,
That is, in the embodiment, the lowermost portion is the front and rear walls 1100 and 1101, the side walls 1102 and 1103, the leg portions 1104 and 1105, and the recessed recesses described later.
1107 is a flat bottom surface. The bottom wall 1106 forms the same flat upper surface with which a part of the lowermost transfer sheet or the sheet receiving plate 62 can come into contact.

As is clear from the above description, the leg portion 1104 of the cassette 11 is
At the position corresponding to the detection protrusion 65 when sliding on the mounting table 5601, a sloped portion 1110 facing forward is formed as shown in FIG. 5d. Notches 1111 and 1112 are formed at both ends of the lower edge of the front wall 1100 of the cassette 11.

The notch 1111 is located at a position corresponding to the sloped portion 1110 of the leg portion 1104, and allows the detection protrusion 65 to pass therethrough.
Further, the depression 1107 is formed by the leg portion 1104 in the bottom wall 1106.
Between the front wall 1100 and the front wall 1100 so as to coincide with the central cutout portion of the front wall 1100.

Further, widthwise slit-like holes 1108 are formed at two positions on both ends of the rear portion of the bottom wall 1106, and a notch 1109 is formed from the front edge at the bottom of the depressed recess 1107. The slit-shaped hole 1108 is a downward folding portion 62 formed at the rear end of the sheet receiving plate 62 dropped in the cassette 11 so that the transfer paper P can be placed thereon.
It is for pressing 00.

The hole 1108 may be provided at an appropriate position in relation to the size of the sheet receiving plate 62, that is, at a position farther forward than that shown in the drawing, for example, at a position around the central portion of the bottom wall 1106, and a known supporting means is used. Of course you can. As described above, the relationship between the hole 1108 and the sheet receiving bent portion 6200 is related so that the sheet receiving plate can be rotated upward by a predetermined amount.

Further, the notch 1109 is provided with the microswitch MS-2 or MS for detecting the transfer paper size protruding from the mounting table 5601.
This is for avoiding the bias of -3, and its position can be changed according to the size of the paper to be stored. The notch 1109 is not needed in the cassette that energizes both microswitches together. In this way, the transfer paper size detection microswitch M
For example, one of S-2 and MS-3 is pushed in using the lower surface of the recessed concave portion 1107 of the cassette 11, and at that time, the time chart of the microcomputer can be selected by the output of the pushed micro switch, as described above. Alternatively, by maintaining the relationship between the number or width or position of the cutouts 1109 and the micro switch so as to urge the display means of the operation unit, it is possible to detect various kinds of transfer paper sizes. Reference numeral 62 denotes a sheet receiving plate, and at the end of loading the cassette, the front edge portion located under the sheet feeding roller 57 has
A friction material 62 'is attached in order to prevent the double-sheet feeding phenomenon when the transfer paper accumulated on the paper decreases.

Further, the sheet receiving plate 62 has a hole 6201, although it is partially embedded in the friction material attaching portion in the figure. This is the actuator a1 of the microswitch MS-1 that detects when the transfer paper is out of the cassette.
It is a hole for immersing. The recessed recessed portion 1107 having the lower surface of the sheet receiving plate as the ceiling, which has been moved back and forth, is for inserting the pressure bonding plate 60 at a predetermined position when the cassette is loaded. As described above, the crimping plate 60 is maintained at the same position as in the lower method (the position indicated by the chain line in FIG. 5d) when the cassette 11 is inserted. Both side plates 1102 of the cassette 11
Further inside, and 1103, there is a plate 63 mounted with a gap from the side plate.

Reference numeral 64 is a known separation claw that engages with both end portions of the front surface of the transfer sheet, and is provided so as to be able to swing up and down with a point 6300 on the rear portion of the plate 63 as a fulcrum.

The structure of the sheet feeding device and the cassette is as described above. Next, the order of loading will be described.

First, the transfer paper is stored in the cassette c corresponding to the size of the transfer paper used, and the separation claw 64 and the transfer paper are securely engaged with each other to complete the preparation.

On the other hand, the cam lever 61 of the loading device is rotated counterclockwise from the position shown in Fig. 5b to the state shown in Fig. 5c.

At that time, in response to the rotation of the cam lever 61, the bifurcated lever 73 is forcibly rotated clockwise by the cam engagement between the upper arm 7301 and the cam surface 6103 of the cam lever 61. Rotatable axis S
H-6 and the forked lever are fixedly installed, and the shaft SH-
Since the crimping plate 60 is fixedly mounted on the plate 6, as a result, the crimping plate 60 also rotates and can be inserted into the recessed concave portion 1107 at the front end of the cassette c from the raised second position in FIG. It is sequentially moved toward the first position below. During the rotation of the cam lever 61, the bent portion 6104 of the cam lever 61
Comes into contact with the lever 76, so that the lever 76 is also rotated clockwise. The turning force of the lever 76 is transmitted to the lock pawl 77 via the rotatable shaft SH-7 for fixing the lever 76, and as a result, the lock pawl 77 projects onto the mounting table 5601 in FIG. 5d. It is lowered from the position toward the retracted position shown by the chain line. On the other hand, the second actuating lever l ₂ causes fixed on a shaft SH-4 is rotated clockwise against the biasing force of the spring SP-2 because the bent portion 6107 and the engagement state of the cam lever 61. Therefore, the microswitch MS-1 for detecting the presence or absence of the transfer paper on the axis SH-4 is shown in FIG.
From the solid line position to the dashed line position. The cam lever 61 acts on the locking member 78 in the same way as it acts on the forked lever 73 during its rotation.

That is, the upper bent portion 78 of the locking member 78 with the cam surface 6105.
Transmit power to 00. Therefore, the locking member 78 rotates clockwise to the position of the chain line (Fig. 5c). The first operating lever l ₁ mounted on the lower bent portion 7801 of the locking member 78 is also the lever.
Rotate counterclockwise by the same amount as 78.

The contact time between the cam surface 6105 and the upper bending portion 7800 of the locking member 78 and the amount of rotation of the locking member 78 are very small, and the immediate locking surface 6106 and the upper bending portion 7800 are Displaced into the engaged state. In this state, if the biasing force on the cam lever 61 is removed, the cam lever 61 is held at the position shown in FIG. 5c. When the cam lever 61 is rotated until the upper end surface 6102 of the recess 6100 comes into contact with the pin 72, the roller element 75 is in a state of engaging with the recess 6108 of the cam lever.

In this series of operations, the rotation amount of the rotation pin 67, that is, this is the arm 68 that holds the first operating lever ₁₁ and the detection protrusion 65.
It can be said that it is the amount of rotation of, but since it is small,
The detection protrusion 65 that projects onto the mounting table 5601 is always described before.
01 It keeps protruding from above.

By the above operation, the pressure plate 60, the lock claw 77 and the micro switch MS-1 (actuator a1) are installed in the cassette 11
Complete the loadable preparation of. Then, when the cassette 11 is placed on the mounting table and slidably inserted thereinto, the notch 1111 of the cassette front wall 1100 does not bring the front wall 1100 into contact with the detection protrusion 65. The cassette 11 advances further forward (upper side in FIG. 5a, left side in FIG. 5b, left side in FIG. 5c). Then, leg 1104
When is approaching the position of the detecting protrusion 65, the front surface portion of the inclined surface portion 1110 contacts the detecting protrusion 65 and sequentially moves the detecting protrusion 65 downward.

When the contact of both advances, namely a first actuating lever l ₁ the amount of rotation of the sensing projections 65 through the arm 68 caused to rotate in the counterclockwise direction, the engaging surface 610b and the locking member of the cam lever 61 The rotation amount capable of releasing the engagement of the upper bent portion 7800 of the 78 is transmitted to the lever 78, and the cam lever is biased by the biasing force of the spring SP-1 and the biasing force of the spring SP-2 that have been pulled until then. 61 rapidly drops in the clockwise direction and returns to the initial position, that is, the state of FIG. 5b. At the same time, the pressure bonding plate 60 raises the front end of the sheet receiving plate 62, and the topmost transfer sheet is fed by the feeding roller 57.
Contact with. Originally, it can be designed so that the loading of the cassette 11 is completed at this point. However, in the embodiment according to the present invention, the slope portion 1110 of the leg portion 1104 is also on the detection protrusion 65 when the detection protrusion 65 is operated, and the lowermost portion of the front wall 1100 is locked by two steps. It is related so that it is in a position that passed the first locking step 7702 of the claw 77,
At this point the loading of the cassette is not complete. The reason for planning in this way is when the loading completion of the cassette 11 is to be performed by the lock claw, and when it is attempted to be performed by the one-stage lock claw, the variation of the component parts, the accuracy at the time of assembly, the structure The above problem and the loading state of the cassette by the operator (for example, in the case of a cassette for B5 due to the small size of the device, more than half of the cassette can be placed on the mounting table 5601, but there is no problem. In the case of the cassette that can store the sheets of paper, if the size of the above-mentioned table 5601 is set to a size such that the table 5601 cannot be held as described above, the leading end of the A3 cassette is Even if it slides on the mounting table 5601 as described above, it is often moved aslant as a whole. Here, such a state is used, and a lock portion (a rising portion 5604 in front of the mounting table 5601 in the embodiment is used). Lock It requires that just a shoulder refers to the distance between the left edge). On the other hand, in terms of lock, there is a conflicting problem that there is no play if there is looseness. The reason why the lock claw 64 has a two-stage structure is to solve both of these problems.

That is, when the cassette 11 is inserted, the cam lever 61 is lowered, and the lock claw 77 is projected, the front wall 11 of the cassette 11 is
Since the first locking step 7702 of the lock claw 77 is engaged with the rear surface of the lower end of 00, the cassette 11 cannot be pulled out unless the cam lever 61 is pushed up again. Further, in this state, the lock claw 77 is not in a completely projecting state because the horizontal plane portion 7704 continuing to the first locking step portion 7702 is pushed down by the front wall 1100. When the cassette 11 is further advanced, when the front wall 1100 comes into contact with the front edge rising portion 5604 of the mounting table 5601, the lock claw 77 rises and the second-stage locking step portion 7703 is moved to the front wall.
Engages with the rear surface of 1100, which completely locks cassette 11 and completes loading cassette 11.

Preventing the cassette 11 from being pulled out by the above first-stage lock means that if the cassette 11 is allowed to be pulled out, the cassette 11 may be reinserted without the cam lever 61 being pushed up again. MS-1, crimp plate
This is because 60 and the like project above the cassette moving path and are damaged. However, the lock pawl 77 has a front surface 7701.
Even if the cassette 11 is inserted while the cam lever 61 is lowered, its front wall 1100 abuts the front end face 7701 to prevent further advancement, and damage caused by incorrect insertion is completely prevented. To be done.

If a certain amount of backlash is allowed, the locking claw 77 may have only one locking step.

When the transfer paper is sent out from the uppermost position from the loaded cassette 11 by the above-mentioned method, the transfer paper P expands upward in the curved portion 8100 of the guide plate 81 while its leading end abuts on the first transport rollers 80, 80 '. Form an exit loop and energize microswitch MS-4. The output signal causes the paper feed motor M to stop, and the paper feed roller 57 is a one-way rotation type, so the transfer paper stands by in this state. After that, when the first carrying roller 80 is operated by an instruction from the microcomputer based on the slit number count of the phase detecting disk 20 of the document placing table 6, the first carrying roller 80 is carried toward the image forming process including the transfer process. Become.

Even if a sheet jam or the like occurs in the state where a part of the first transport roller 80 remains, the lever 8001 is urged counterclockwise by the lowering of the holding member U that holds the transport means. The shaft of the roller 80B is connected to the cam portion 8
Since 102 pushes up and forms a space there, it can be easily removed. When removing the cassette 11 from the device, such as when the transfer paper runs out or when using different size transfer paper, the cam lever 61
All you have to do is raise.

As described above, according to the embodiment, the cassette can be automatically loaded into a predetermined operating state only by inserting the cassette with an extremely simple structure, and the cam lever can be pulled out only once to pull out the cassette. Therefore, there is a great advantage that the cassette can be loaded extremely easily and surely, and the malfunction can be prevented.

The sheet feeding device 56 is locked at its front end by a locking member 250 provided on the bottom plate 2 as shown in the drawing, and at the rear end thereof at the bottom plate 2.
It is screwed to the rising part 280. Although not mentioned above, a recess is formed on the right side cover 4'to position the grip portion H of the lever 61 on the outside thereof, and a vertically long opening is formed to allow the lever 61 to move up and down. I am doing it. Therefore, only the grip H is exposed when the sheet feeding device is incorporated in the apparatus body and the side cover 4'is attached.
Also, the method of attaching the paper feeding device 61 is simple as described above, and even if the cover is attached to the main body, it can be easily stopped by a clamp screw or the like, so if there is a failure or damage to members, Quickly detached from the main body,
Alternatively, it can be attached to the main body.

Next, the transport means 82 will be described. The transfer means 82 transfers the transfer paper P sent by the first transfer roller 80 of the paper feeding device so as to be superposed on the image area of the photosensitive drum 13.
A guide plate 8200 that guides the toner image carried on the photosensitive drum, a transfer device 83 having a function of transferring the toner image carried on the photosensitive drum onto the transfer paper, a photosensitive drum 13 after transfer and a transfer paper that moves in an electrostatic adsorption state. It is constructed integrally with a separating static eliminator 84 which can be connected to the A and C power sources so that it can be separated from the drum. B is a conveyor belt, and S is a suction box that can be connected to suction means (not shown).
This will be described below with reference to FIG. U is a holding member that holds each member. A bent portion 8203 having a predetermined area is formed on the right upper end of the guide plate.
It is designed to fix the 8200. Further, as shown in FIG. 2, the end 8204 protruding further to the right of the holding member has an upper guide plate 8200 'provided at the bottom of the holding unit 3920 of the developing device 39 when the conveying means 82 is in the normal position. It comes in contact with a part of the. In FIG. 2, the end 8204 is shown.
Are shown as lines emerging from a portion of the lower guide plate 8200. In addition, the reference symbol Mag is provided on the upper guide plate 8200 '.
Shown as is a magnet for collecting the developer if it falls. A plurality of openings 8201 formed on the guide plate 8200 detect water droplets generated on the surface of the photosensitive drum or moisture contained in the developer, and other openings are provided so that a normal copy image can always be obtained. It is an opening for preventing dew condensation provided in association with the element. This is defined as an appropriate position and shape so that heat from a heat source indicated by reference symbol h can be guided to the magnetic brush type developing device 39 and at least the photosensitive drum surface 13 facing the device. Reference numeral 8201 'is one means for achieving the above-mentioned purpose, and a punched plate is hung so that heat is distributed to the photosensitive drum side and the developing device side. Heat source h
For example, the heat may be forcibly blown by a small fan. 8210 and 8220 are the transfer devices
It is a rail for attaching 83 and the static eliminator 84.

B is a conveyor belt stretched around rollers 8230 and 8240 and a roller (only the shaft is shown) having a shaft SH-9. A hole 8250 having an appropriate shape and an appropriate size is provided on the upper plate of the suction box S, and the transfer paper P after passing through the transfer process is formed.
Is sucked onto the belt B to ensure the conveyance. The driving of the belt B can be achieved by connecting any one of the plurality of rollers to a driving system.
The holding member U in which various members are integrated as described above can rotate in the direction of the arrow with the fulcrum of the roller 8240, which is one factor of the conveying means 82, as a fulcrum.

The amount of rotation can be arbitrarily determined by an appropriate mechanism. The right end portion 8205 of the holding member U is moved by the sheet feeding device 56 when it is dropped and rotated.
The lever 8001 provided on the is rotated counterclockwise. At that time, a gap is formed between the pair of first transport rollers, as described above. Reference numeral 85 denotes the entire lever device having a function of holding the holding member U at a predetermined position and a function of rotating and dropping the holding member U as described above. Reference numeral 8500 is an operation lever, which is loosely fitted on the shaft SH-11. Axis SH-
11 above, and an arm 85 inside the operation lever 8500.
01 is attached. The rod 8502 provided at the free end of the arm 8501 ultimately positions the holding member U at predetermined positions. The holding member is rotated and dropped by rotating the operation lever 8500 in the arrow direction. The operation lever 8500 is formed with bent portions 8510 and 8511 extending rearward in the figure. 8520 is the rear side of the operating lever 8511 and is the shaft SH-
It is a driven lever that is fixedly mounted on 11. A bent portion 85 that engages with one bent portion 8511 of the operating lever
21 is provided. 8522 is a pin to be implanted in the driven lever,
Numeral 8523 is a hook loosely fitted on the pin, and is urged clockwise by a spring 8524. The solid line state in the drawing shows a state in which the locking portion 8525 is engaged with the locking portion 8600 of the locking plate 86. Reference numeral 8526 denotes one end of a hook that engages with one bent portion 8510 of the operation lever.

With such a configuration, the handle 8530 is now rotated in the direction of arrow A, and the bending portion 8510 of the operation lever exerts a force to overcome the biasing force of the spring 8524 at the end of the hook 8523.
When given to the 8526, the hook locking part 8525 gradually becomes the locking plate 86.
When the operation lever begins to disengage from the locking portion 8600 and the operation lever is tilted to the position shown by the chain double-dashed line, the engagement is released.

As apparent from the figure, in the embodiment, when the operation lever is brought to the position, the bent portion 85 of the operation lever
Since 10 is set so as to contact a part of the driven lever 8520, the turning force of the operation lever 8500 thereafter is transmitted to the driven lever. This means pivoting of the shaft SH-11 and therefore
Since the rod 8502 fixed on the arm 8501 rotates, the holding member U also rotates and falls in the clockwise direction with the shaft SH-10 as a fulcrum.

FIG. 8b is a view showing the return of the holding member.

When power is applied to the handle 8530 in the direction of the arrow B, the force is applied by contacting the bent portion 8521 of the driven lever 8520 while the operation lever is rotating from the bent portion 8511. Hook 8523
Is rotated according to the rotation of the bent portion of the operation lever 8520, and when the operation lever reaches a predetermined position, its locking portion 8525 engages with the locking portion 8600 of the locking plate and holds it. Hold the member U in the position of FIG.

The handle 8530 has a portion 8531 extending to the front side,
This is associated with the controller of the (fool-proof) device so that the copying operation cannot be performed when the holding member U is dropped.

With the configuration as described above, the holding member U can be dropped and returned by one-touch operation. Further, since the transfer device and the like are integrally attached to the holding member, if the holding member U is dropped in the case of a paper jam or the like, as compared with the conventional device, the transfer device is held independently. The great effect that a sufficient space for inserting a hand under the photosensitive drum 13 can be formed is obtained. Further, it becomes easier to set the distance between the photosensitive drum and the transfer device (in particular, the wire electrode) as compared with the conventional device.

The structures of the transfer device 83 and the static eliminator 84 are almost the same as those of the charging device 38. However, as shown in FIG. 9, the static eliminator 84 connected to the AC power source has an opening on its side shield.
8400 is provided. This is provided in order to remove the ionic wind generated during corona discharge, which adversely affects the sensitivity characteristics of the photoconductor. Ionic wind refers to a gas flow generated when charged particles hit gas molecules. The gas is electrically neutral and contains chemically active particles. 8401 is a guard member made of an insulating material for preventing the contact of the tip of the transfer paper that has passed on the transfer device with the static elimination electrode 8402 made of a wire and damaging the electrode, and made of an insulating material. is there. The guard member 8401
Are independently detachably attached to the static eliminator 84. The above construction can eliminate the conventional drawbacks of using a long nylon thread, such as difficulty in tensioning and replacement with a new thread when one point is cut. In the drawing, a claw 8402 provided on the lower portion of the guard 8401 is hooked on the opening 8400 to fix the guard, but the mounting structure can be freely changed. The same applies to the guard shape. A roller type fixing device 87 applies heat to the transfer paper P carrying the toner image by the bias of the transfer device 83 to melt and fix the toner on the transfer paper. 8700 is a heating roller having a heating element composed of, for example, a halogen lamp, the surface of which is coated with a resin having good releasability for toner, such as tetrafluoroethylene. Reference numeral 8701 denotes a pressure-bonding roller which is arranged so as to rotate with a predetermined pressure with the heating roller at the time of fixing operation, and the surface thereof is coated with, for example, silicone resin. It should be noted that the distance between the contact portion of both rollers (the transfer paper sandwiching portion) and the position where the path of the transfer paper P intersects the perpendicular line passing through the center of rotation of the photosensitive drum is simply defined by the distance of the transfer paper to be used. The size is set to be shorter than the length in the transfer direction, and the device is downsized. However, in the apparatus of the embodiment, as described above, A3, B4, A4
It is configured to use B5 and B6 size transfer papers, and the spacing is approximately the same as the length of B4 size. Therefore, the above expression is appropriate in terms of A4, B5 and B6 size transfer papers. It does not seem that, but in the embodiment, it is clear that the distance between the perpendicular line passing through the rotation center of the roller and the photosensitive drum and the position where the transfer paper passage intersects is shorter than the length of the A3 size transfer paper in the transport direction. This means that the above-mentioned setting conditions are effective and the same effect can be obtained, for example, when a dedicated machine corresponding to the transfer paper size is assumed, and thus such expression is used.

The heating roller 8700 and the pressure-bonding roller 8701 rotate and pressure-bond when the main switch 10 in FIG. 1 is turned on so that they are kept apart from each other and are kept in a non-rotation state, and when the print button is pushed. It is controlled to maintain the condition.

When the main switch is ON, the heating element 8702 is energized. The structure will be described with reference to FIG.

8702 is a heating element, and its filament structure is segmented as shown in FIG. Further, the distribution viewed from the heat generation capacity is set so that the end portion side is larger than the center portion of the roller, and when comparing the end portions, the side connected to the drive system is It is set to have a larger heat generation capacity than the other side.

Reference numeral 8703 denotes a temperature detecting element attached near the back surface of the heating roller 8700.

Reference numeral 8704 is a reflecting plate whose inner surface is, for example, a mirror-finished aluminum plate. Needless to say, the reflector may be used without surface treatment. 8705 is a heat insulating material attached to the outside of the reflection plate. Both of the above are the heating rollers
It is attached to cover the 8700.

This serves to protect the temperature detecting element 8703 from making an erroneous measurement due to the wind coming from the outside on the right side (sheet discharge side) in the figure.

Reference numeral 8706 denotes a separating claw formed by bringing the tips of the heating roller 8700 and the pressure roller 8701 into contact with part of their peripheral surfaces. In the figure, only the upper separation claw is shown together with the holding material. The separating claw has mechanical strength, high temperature characteristics, releasability to toner,
In consideration of ensuring the precision of the tip of the separating claw by molding, it is formed from a polyphenylene sulfide-based material containing 2 to 40% by weight, preferably 5 to 25% by weight of Teflon.
The portion 8707 that will come into contact with the transfer paper after fixing is the first
As shown in FIGS. 0c and d, it has a narrow protrusion.

8708 is a concave portion that is provided so that when toner that has not been completely fixed yet comes into contact with and adheres to it, it can be sequentially deposited.
8709 is a hole for further containing the toner that may be accumulated. Reference numeral 8710 denotes an opening provided in the upper portion of the frame body 8711 so that wind entering from the outside (right side in FIG. 10A) can be transferred along the reflection plate 8704 and discharged as described above.

8712 is a regulating plate that regulates the air discharged from the opening and guides it to a position that does not adversely affect the side temperature of the temperature detecting element 8703. Reference numeral 8713 indicates a paper ejection guide.

It should be noted that the centers of the heating roller 8700 and the pressure-bonding roller 8701 are not on the same vertical plane, but the heating roller 8700 is displaced toward the paper ejection guide side with respect to the pressure-bonding roller 8701. An angle α formed by a line connecting the rotating shafts of both rollers with respect to a vertical line drawn on the rotating shaft of the pressure bonding roller is set to 15 degrees. In this way, the heating roller 8700 is brought closer to the paper discharge side is
This is to reduce the tendency of the transfer paper to wind around the heating roller.

Reference numerals 8714 and 8715 are guide plates for guiding the transfer paper P sent by the transporting means 82, and 8716 is an elastic guide plate made of a thin polyester film having elasticity. Functions of these guide plates will be described with reference to FIG. The horizontal position of the lower guide plate 8715 is set to be slightly higher than the top of the pressure roller 8701. Further, it is positioned slightly below the height at which the copy paper is conveyed.

The elastic guide plate 8716 is on the mounting side of the lower guide plate, that is, on the inclined portion 8718 formed between the upright portion 8717 and the lower guide plate, the free end of which is smaller than the lower guide plate 8715. It is attached so as to project.

Although the elastic guide plate is fixed in the embodiment, the elastic guide plate 8716 is made of another member so that it can move up and down.
May be attached to.

The upper guide plate 8714 has a right side portion curved so as to approach the lower guide plate 8715 as it approaches the pair of rollers.

In practice, the radius of curvature was 20-35 mm. This upper guide plate 8714 has, for example, a radius of the heating roller 8700.
20 mm, as described above, when the vertical center line drawn through the center of the pressure roller 8701 and the angle α formed by connecting the centers of both rollers are about 15 degrees, the tip of the roller is the axis of the heating roller (Fig. It is preferable to dispose it so that it can be positioned 10 mm below (not shown) and that it is positioned 2.5 mm away from the outer peripheral surface of the heating roller. The reason why the elastic guide plate is arranged is to prevent image blurring. That is, as described above, when the distance between the rollers and the photosensitive drum (which would be better understood as a transfer device rather than the transfer device) is shorter than the length of the transfer paper in the transport direction, Since the rear end of the transfer paper is also attracted to the photosensitive drum 13 in a state where the front end of the transfer paper is nipped by the both rollers, it is possible to transfer the transfer paper such as the both rollers and the photosensitive drum which are one element of the fixing device. Unless the linear velocities of the movable members (rotating members) that can affect the transfer speed are exactly the same, a phase shift easily occurs between the photosensitive drum being transferred and the transfer paper attracted to the drum. It is easy to cause image blur. Therefore, by using the elastic guide plate 8716, when the transfer paper has a slack and a difference in moving speed occurs, the loosened portion is attracted to the copy paper so that a copy image without blur can always be obtained. Is.

It is desirable to set the surface speed of the roller pair to be slightly slower than the surface speed of the photosensitive drum.

〔The invention's effect〕

Although the present invention has been described with reference to the embodiments, the present invention has the following effects.

The size of the copying machine, that is, the height, the depth, and the left and right lengths greatly depend on the exposure optical system and the shape of the transfer paper transport path.

In the present invention, the height of the copying machine is kept low by adopting an optical system having an optical path parallel to the platen, that is, horizontal, and by making the transfer paper transport path substantially horizontal.

By using a photosensitive member having a seamless photosensitive layer as the photosensitive member, the diameter of the photosensitive member can be reduced regardless of the size of the copy image.
The height of the copying machine can be further reduced due to the shape of the transfer paper transport path.

Further, the length from the transfer position to the fixing position was made shorter than the length (maximum length) of the transfer paper, so that the left and right lengths of the copying machine were compressed.

Making the transfer paper conveyance path linear also has the effect of preventing paper jams. Even if a paper jam occurs, since the paper is conveyed straight, the work for clearing the paper jam is simplified, and the difficulty of handling the machine encountered when the machine is downsized can be prevented.

Furthermore, since the heating roller and the pressure roller of the fixing device are configured so that the heating roller is closer to the paper discharge side, the transfer paper is prevented from being wrapped around the heating roller, and the paper jam is more effectively prevented. Was done.

[Brief description of drawings]

FIG. 1 is an external view of an electronic copying apparatus according to an embodiment of the present invention, FIG. 2 is a schematic view of the above embodiment, FIG. 3 is a view showing a mounting state of a photosensitive drum of the above embodiment, and FIG. Is a diagram showing the phase detecting means of the photosensitive drum in the above embodiment, FIG.
FIG. 6 is a diagram showing the structure of the sheet feeding section of the above embodiment, FIG. 6 is a diagram showing the cassette used in the above embodiment, FIG. 7 is a diagram showing the transfer paper conveying means of the above embodiment, and FIG. FIG. 9 is a diagram showing an operation mechanism of the conveying means, FIG. 9 is a diagram showing the charge eliminating device of the above-mentioned embodiment, and FIG. 1 is the whole apparatus, 6 is a document placing table, 11 is a cassette, 13
Is a photosensitive drum, 23 is an exposure lamp, 39 is a developing device,
80 is a paper feeding means, 82 is a conveying means, and 87 is a fixing means 90.
Is a cleaning means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page Judge Chief Koki Kokizawa Judge Judge Yamazaki Yutaka Saito Nobuto (56) Reference JP-A-52-105831 (JP, A)

Claims (2)

[Claims] 1. A. Original plate that forms the upper surface of the copier b. A drum-shaped photoconductor disposed below the platen, rotatable and having a seamless photoconductive surface; c. A charging means disposed near and above the photoconductor to uniformly charge the photoconductor; d. Exposure means for performing scanning exposure by forming an optical path parallel to the document table and an optical path bent obliquely downward from the parallel optical path to the photoconductor, and performing scanning exposure; A dry developing means disposed near and near the photoreceptor, f. Transfer means disposed near and below the photoconductor; Separating means disposed near and below the photoreceptor, h. A cleaning means disposed near the photoconductor and between the separating means and the charging means; Transfer paper feeding means for sending the transfer paper to the transfer position in synchronization with the exposing means, Heat roller fixing type fixing means, and le. A transfer paper path forming means for forming a transfer paper path between the separating means and the fixing means, supporting the transfer means and the separating means, and swinging the transfer paper path; The transfer means, the separating means, the transfer paper path forming means and the fixing means are arranged such that the path of the transfer paper passing through these means is linear, and the fixing is performed from the transfer position on the transfer paper path. The heating roller and the pressure roller are configured such that the length up to the means is shorter than the maximum length of the transfer paper used, and the heating roller of the fixing means is closer to the paper discharge side than the pressure roller. An electronic copying apparatus characterized in that a swing space of the transfer paper passage forming means is formed below the transfer paper passage forming means. 2. The electronic copying apparatus according to claim 1, wherein said transfer paper passage forming means is provided with a suction for adsorbing the transfer paper.