JP2008087875A - Paper conveying device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper conveying device provided with an opening and closing device capable of easily changing required amount of opening when taking procedures in the jammed state and required amount of opening when performing maintenance work. <P>SOLUTION: This paper conveying device is provided with a lower guide forming a paper conveying part, an upper guide forming the paper conveying part together with the lower guide in a closed condition and being turnable relative to the lower guide to open the paper conveying part in an alligator mouth state, and a damper provided between the upper guide and the lower guide and having repulsion force for holding the upper guide when opening the paper conveying part. This paper conveying device has a first mounting position of the damper for changing an angle of opening by changing the length of operation of the damper and holding the upper guide independently when opening the paper conveying part and a second mounting position of the damper for changing to the angle of opening for holding the upper guide independently without changing the length of operation of the damper. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is a paper transport device that can divide a paper transport guide into two parts.

  For example, the present invention relates to a paper transport device such as a copying machine and a printer that can be opened and closed with one end as a fulcrum, such as a crocodile mouth, and includes a top and bottom damper.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as a printer, a fax machine, a copier, or a printing machine, an image is formed by an electrophotographic system, an offset printing system, an ink jet system, or the like. As an example of such an image forming apparatus, there is a color image forming apparatus that forms a color image by an electrophotographic method, and such a color image forming apparatus mainly includes an image forming unit that forms a plurality of images. The toner image is transferred directly from the photosensitive member to the sheet as a transfer method, and a tandem method in which the plurality of image forming units are arranged side by side, a rotary method in which the plurality of image forming units are arranged in a cylindrical shape, and a transfer method. It is classified into a direct transfer method and an intermediate transfer method in which the image is once transferred to an intermediate transfer member and then transferred to a sheet.

  Here, the intermediate transfer tandem method in which a plurality (four) of image forming units are arranged on the intermediate transfer belt does not need to hold the sheet on the transfer drum or the transfer belt unlike the direct transfer method. Because it can handle a wide variety of sheets such as thick paper and coated paper, the paper path to the secondary transfer unit can be configured simply, and the flexibility of the method of stretching the intermediate transfer belt is high. This is also advantageous in downsizing.

  In an intermediate transfer tandem type image forming apparatus, it is necessary to access the necessary part from the outside in the case of replenishment, replacement, service maintenance, or sheet removal work when a jam occurs. Department.

  To access the paper transport unit, pull out a transport frame with multiple transport units to the front of the device, and open the guide plate on one side of each transport unit upward or downward to perform jam processing. Do.

  Here, the opening / closing configuration of the upper-opening type paper transport unit will be described. At the time of jam processing, the hinge portion is set as the center of rotation, the two guide plates constituting the paper transport path are divided into upper and lower parts, and the upper guide is opened and closed in the direction of gravity to perform jam processing. A damper is used as an opening assisting force of the upper guide during the jam processing, and to maintain the upper guide in a self-supporting manner so as to secure a jam processing space and improve a jam processing operation. The damper spans the upper guide and the lower guide, and the end of the damper is arranged on the frame of the upper and lower guides in a state where the damper is rotatable (Japanese Patent Laid-Open No. 11-084791).

Fluid dampers and spring dampers, including gas springs, are used for the top-opening damper. Also, the opening force of the upper guide can be changed by changing the mounting position of one end of the damper without changing the repulsive force of the damper itself. Is finely adjusted (JP-A-6-324529).
Japanese Patent Laid-Open No. 11-084791 JP-A-6-324529

  However, in the upper-opening type paper transport unit using the damper as in the above-described conventional example, in the jam processing work space alone, for example, transport rollers and motors provided on the frame on the lower guide side, When exchanging electrical components such as sensors and substrates, the work space was insufficient. Especially when working near the hinge, it is difficult to access by a driver or the like due to the restriction of the opening space by the operating length of the damper. The paper transport unit was once lowered from the transport frame, the damper and hinges were removed, the upper guide was removed, and then the lower guide side was accessed, so maintenance efficiency was very poor.

  In view of the above problems, an object of the invention according to the present application is to provide a paper transport device provided with an opening / closing device that can easily change the required opening amount during jam processing and the opening amount required during maintenance work.

To achieve the above objective,
According to a first aspect of the present application, in the sheet conveying apparatus, the sheet conveying unit is formed together with the lower guide in a closed state with the lower guide forming the sheet conveying unit, and the sheet conveying unit can be opened in the alligator state. An upper guide that is rotatable with respect to the lower guide, a damper that is provided between the upper guide and the lower guide and has a repulsive force that holds the upper guide when the paper conveying unit is opened, and an operating length of the damper changes. As a result, the opening angle changes, and when opening, the damper has a first mounting position that can hold the upper guide independently, and it can be changed to an opening angle that can hold the upper guide independently without changing the operating length of the damper. A second damper mounting position.

  As described above, it is possible to reduce the load on the operator when opening and closing the upper guide by securing the damper at the first mounting position and to secure the necessary opening amount for the jam processing work, and to install the damper at the second mounting position. The necessary opening amount for maintenance work is secured. In addition, by making it possible to easily change the mounting position, it is possible to improve the maintainability by removing the work load such as temporarily lowering the paper transport unit from the transport frame during maintenance and removing the damper, hinge, and upper guide. Is possible.

  According to a second aspect of the present application, in the paper transport device, the damper support member attached to the damper at the second attachment position includes a damper rotation prevention member, and the rotation prevention member and the support member are integrally configured. The support member is attached in the vicinity of the rotation center on the lower guide side of the sheet conveying apparatus.

  As described above, by stopping the rotation of the damper, it is possible to prevent the upper guide plate from falling during maintenance and to secure a working space with both hands.

As explained above,
According to the first invention of the present application, it is possible to reduce the load on the operator when opening and closing the upper guide by attaching the damper to the first attachment position and to secure the necessary opening amount for the jam processing work. The necessary opening amount for maintenance work is secured by installing a damper at the mounting position of 2. In addition, by adopting a configuration that allows the attachment position to be easily changed, the work load of removing the damper, hinges, and upper guide once during the maintenance to remove the paper transport unit from the transport frame is eliminated, thereby improving maintainability. Is possible.

  According to the second invention of the present application, by stopping the rotation of the damper, it is possible to prevent the upper guide plate from falling down during maintenance and to secure a work space with both hands.

(First embodiment)
FIG. 1 shows a cross-sectional view of an image forming apparatus provided with a paper conveying device 50 according to the present invention.

  In FIG. 1, the transfer material S is stored in a form of being stacked on a lift-up device 52 included in the paper feeding device 51, and is fed by the paper feeding means 53 in accordance with the image forming timing of the image forming apparatus. . Here, as the paper feeding means 53, there are a system using frictional separation by a paper feeding roller, a system using separation adsorption by air, and the like. In FIG. . The transfer paper S sent out by the paper feeding means 53 passes through a transport path 54a of the transport unit 54, is transported to the pre-registration transport device 50, and is temporarily stopped before being transported to the registration unit. Cancel the transport variation. In addition, when the transfer material S sent from the paper feeding device 51 is double fed, the double feed detection sensor of the pre-registration transport unit 50 detects the double feed, stops the transfer material S immediately before the registration unit, and transports it. Prevent defects. The restarted transfer material S is subjected to skew correction and timing correction in the registration unit 55 and then sent to the secondary transfer unit. The secondary transfer portion is a toner image transfer nip portion to the transfer material S formed by the substantially opposite secondary transfer inner roller 503 and secondary transfer outer roller 56, and has a predetermined applied pressure. By applying an electrostatic load bias, an unfixed image is attracted to the transfer paper.

  With respect to the transfer process of the transfer material S to the secondary transfer unit described above, a process for forming an image sent to the secondary transfer unit at the same timing will be described. The image forming unit 513 mainly includes a photoreceptor 508, an exposure device 511, a developing unit 510, a primary transfer device 507, a photoreceptor cleaner 509, and the like. The exposure device 511 emits light based on a signal of image information sent to the photosensitive member 508 rotated in the direction of an arrow A in the figure, the surface of which has been uniformly charged in advance by a charging unit, and the diffraction unit 512 and the like. A latent image is formed through the above.

  In this way, toner development is performed on the electrostatic latent image formed on the photoconductor 508 by the developing device 510, and a toner image is formed on the photoconductor. Thereafter, a predetermined pressure and an electrostatic load bias are applied by the primary transfer device 507, and a toner image is transferred onto the intermediate transfer belt 506. Thereafter, the transfer residual toner slightly remaining on the photosensitive member 508 is collected by the photosensitive member cleaner 509 and is prepared for the next image formation again. In the case of FIG. 5, the image forming unit 513 described above includes four sets of yellow (Y), magenta (M), cyan (C), and black (Bk). Of course, it is not limited to four colors, and the order of colors is not limited to this.

  Next, the intermediate transfer belt 506 will be described. The intermediate transfer belt 506 is stretched by rollers such as a drive roller 504, a tension roller 505, and a secondary transfer inner roller 503, and is conveyed and driven in the direction of arrow B in the figure. Therefore, the image forming process of each color processed in parallel by the Y, M, C, and Bk image forming apparatuses 513 described above is performed at the timing of superimposing on the upstream toner image primarily transferred onto the intermediate transfer belt. . As a result, a full color toner image is finally formed on the intermediate transfer belt 506 and conveyed to the secondary transfer portion.

  As described above, the full color toner image is secondarily transferred onto the transfer material S in the secondary transfer portion by the transfer process and the image forming process of the transfer material S described above. Thereafter, the transfer material S is conveyed to the fixing device 58 by the pre-fixing conveyance unit 57. The fixing device 58 melts and fixes the toner on the transfer material S by applying a predetermined pressurizing force by a substantially opposed roller or belt and generally a heating effect by a heat source such as a heater. The transfer material S having a fixed image obtained in this way is discharged directly onto the paper discharge tray 500 by the branch transport device 59, or transported to the reverse transport device 501 when double-sided image formation is required. Route selection is performed.

  A transport operation when double-sided image formation is required will be described. The transfer material S sent to the reverse conveying device 501 is switched back and forwarded by a switchback operation and conveyed to the double-sided conveying device 502. Thereafter, the transfer unit 54 joins from the refeed path 54b of the transport unit 54 in time with the transfer material of the succeeding job transported from the paper feeder 51, and is similarly sent to the secondary transfer section. The image forming process on the back side is the same as that on the front side, and is omitted.

  Here, the jam processing when the image forming apparatus is jammed will be described. In FIG. 1, the registration device 55, the pre-registration conveyance device 50, and the double-side conveyance device 502 are provided with a paper conveyance frame (not shown), and as described above, the paper conveyance frame is pulled out toward the image forming apparatus. It is possible to pull out all the paper transport devices at once. Each unit guide plate opens upward, opens downward, and opens toward the release space. A specific configuration will be described below by taking the pre-registration transport device 50 as an example of a paper transport unit having an upwardly opening guide configuration.

  2 and 3 are perspective views of the pre-registration conveyance device 50 according to the embodiment of the present invention, FIG. 2 is a damper arrangement diagram during jam processing, and FIG. 3 is a damper arrangement diagram during maintenance.

  In FIG. 2, the pre-registration conveyance device 50 includes an upper guide 100, a lower guide 101, a hinge portion 102, a gas damper 103, a damper upper stay 104, a damper lower stay 105, an upper guide holding stay 106, a lower conveyance plate front 107, and a lower conveyance. It is composed of a frame back 108, a bottom plate 109, a transport roller 110, a drive motor 111, a substrate 112, a double feed detection sensor 113, and a corrugated screw 114.

  In FIGS. 2 and 3, the gas damper 103 is fixed to the lower conveyance frame front 107 and the upper guide 100 by a step screw 114 through a damper upper stay 104 and a damper lower stay 105 so as to be rotatable. When the paper is passed, the gas damper 103 contracts as shown in FIG. 4, and the upper guide 100 and the lower guide 101 are closed. Normally, the lower end of the gas damper 103 is fixed to the first mounting position, specifically, to the lower stay 105 of the damper so as to be rotatable. During the jam processing, the repulsive force of the gas damper 103 is used to Helping force. As shown in FIG. 2, the upper guide 100 is held by itself when opened, and the operator can perform jam processing with both hands.

  On the other hand, in FIG. 2, when the service person replaces electrical components such as the transport roller 110, the drive motor 111, the substrate 112, and the double feed detection sensor, the replacement work is performed after the lower guide 101 is removed. However, in particular, when exchanging the transport roller 110 and the like in the vicinity of the hinge portion 102, maintenance work is narrow in the work space at the time of jam processing, and the hand of the driver or operator cannot be accessed. Therefore, the step screw 114 on the damper lower stay 105 side which is the first mounting position of the gas damper 103 is removed, and the lower end of the gas damper 103 is moved to the upper guide holding stay 106 which is the second mounting position while lifting the upper guide 100. When applied, the upper guide 100 opens approximately 90 ° relative to the lower guide 101 (FIG. 3). Accordingly, it is possible to widen the working space of the hinge portion 102 without removing the pre-registration conveyance device 50 from the image forming apparatus main body and removing the hinge portion 102 and the upper guide.

  A detailed view of the upper guide holding stay 106 is shown in FIG. In FIG. 5, the upper guide holding stay 106 includes a stay member 200, a pin member 201, and a rotation prevention member 202. The rotation prevention member 202 is configured integrally with the stay member 200, and the pin member 201 is crimped to the stay member 200. Yes. By preventing the rotation of the gas damper 103 by the anti-rotation member 202, the upper guide 100 is prevented from falling down, and the service person can perform maintenance work with both hands.

  As mentioned above, it is possible to maintain the service by using the function of the original damper that uses the repulsive force at the time of expansion and contraction and the damper at the time of extension as a stick as a structure having two mounting positions of the damper. It is possible to easily secure a working space.

FIG. FIG. 6 is a pre-registration conveyance device diagram during jam processing. Fig. 3 is a pre-registration transport device diagram during maintenance. FIG. 5 is a pre-registration conveyance device diagram when the guide is closed. FIG.

Explanation of symbols

2 Pattern detection means
3 First detection position
4 Second detection position
5, 6 Transport roller
7 Registrar Roller
9 Arithmetic processing part
11 Upper guide plate
12 Drive shaft
13 Drive roller
14 Followed roller
15 Pressure spring
16 Front plate
17 Rear plate
18 Stay members
19 Paper detection sensor
20 Driven shaft
30 Movable guide
31 Abutting reference member
32 Skew feed roller
33 Fixed guide
50 Transfer machine before cash register
51 Paper feeder
54 Transfer device
55 Registration device
56 Roller outside secondary transfer
58 Fusing device
100 Top guide
101 Lower guide
102 Hinge part
103 Gas damper
104 Damper upper stay
105 Damper lower stay
106 Upper guide holding stay
107 In front of lower transfer frame
108 Back of lower transfer frame
109 Bottom plate
110 Conveyor roller
111 Drive motor
112 substrate
113 Double feed detection sensor
114 corrugated screws
200 Stay material
201 Pin member
202 Detent member
501 Reverse transfer device
502 Duplex conveyor
506 Intermediate transfer belt
508 photoconductor
511 Exposure equipment
513 Image forming unit
80 line sensor
82F, 82R Conveyor roller section
91 Confluence pass

Claims (4)

  A lower guide that forms a paper transport section, an upper guide that is formed with the lower guide in a closed state, and that is rotatable with respect to the lower guide so that the paper transport section can be opened; A damper that is provided between the upper guide and the lower guide and that generates a repulsive force that holds the upper guide when the paper transport unit is opened, and the opening angle changes as the operating length of the damper changes. A first mounting position of the damper where the upper guide is held by the repulsive force of the damper when opened, and a second mounting of the damper where the upper guide is held by the damper without changing the operating length of the damper A sheet conveying device characterized by having a position.   When the damper is attached to the first attachment position, the opening angle when the damper is attached to the second attachment position is larger than the largest opening angle at which the upper guide can be held by the repulsive force of the damper. The sheet conveying apparatus according to claim 1, wherein the sheet conveying apparatus is large.   The sheet conveying apparatus according to claim 1 or 2, wherein the damper support member attached to the damper at the second attachment position includes a damper rotation preventing member, and the rotation stopper member and the support member are integrally configured. The paper conveying apparatus, wherein the support member is attached in the vicinity of the rotation center on the lower guide side of the paper conveying apparatus.   An image forming apparatus comprising the sheet conveying device according to claim 1.

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