JP4920882B2 - Conveying member releasing device and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a releasing device for a pair of conveying members that sandwich and convey a sheet, and an image forming apparatus including the releasing device.

  In an image forming apparatus such as a printing apparatus or a copying machine, a sheet is nipped and conveyed by a pair of conveying members, but the sheet may be jammed for some reason. In this case, the device was stopped, the abnormal part was inspected, and the jammed paper was removed. At this time, the pair of transport members may stop in contact with each other, and the paper sandwiched between these transport members cannot be easily removed. There is a problem that the handling work at the time of paper jam becomes very complicated.

  Therefore, in Patent Document 1, a conveyance abnormality in a sheet conveyance path is detected from a pair of sheet feed rollers that can move in a direction in which one approaches or separates from the other and conveys the printing sheet when approaching. Then, the structure which prevents the approach of one paper feed roller with respect to the other paper feed roller using a prevention means is proposed. The blocking means includes a cam that moves the arm member in and out, a stopper that protrudes on the rotation trajectory of the arm member to block the movement of the arm member, and a driving means that moves the stopper, Then, the drive means is driven to prevent the arm member from moving in the proximity direction.

Japanese Unexamined Patent Publication No. 7-237782

  In Patent Document 1, the arm member is rotated by rotating the cam so that one roller is brought into contact with / separated from the other roller, and a stopper is projected on the arm rotation locus to move the arm member in the proximity direction. Restricts movement. However, when the drive means is driven due to an abnormal conveyance of paper jam or the like while the roller pair is in contact, it is difficult for the arm member to get in the way and cause the stopper to protrude on the rotating track. If the arm member does not occupy the separated position due to rotation, the stopper cannot function. For this reason, even if the driving means for driving the stopper is immediately activated due to conveyance abnormality, the pressure contact state of the roller cannot be released immediately depending on the position of the arm member, and the sheet is fed in the conveyance direction by the roller pair in the pressure contact state. As a result, there is a problem that the state of the paper jam becomes worse and the release operation becomes complicated.

  An object of the present invention is to provide a release device that can easily perform a paper jam release operation and an image forming apparatus including the same.

In order to achieve the above object, a conveying member releasing apparatus according to claim 1 of the present invention includes a pair of conveying members for nipping and conveying a sheet, and a direction in which one of the conveying members approaches or separates from the other. An arm member for enabling movement of the arm member, a mechanism having a cam for swinging the arm member, a detection means for detecting paper jam, and a cam when paper jam is detected by the detection means It is characterized by having a moving means for moving the arm member in a direction in which one of the conveying members is separated from the other without operating, and a drive source for driving the moving means.

The present invention is characterized by having control means for operating the drive source when a paper jam detection signal is input from the detection means .

In the present invention has a release command means for issuing a release command signal, the control means may release command signal from the cancellation instruction section is characterized by a Turkey to operate the drive Dogen as they are entered.

  The present invention is characterized by having a return command means for issuing a return signal, and when the return command signal is input from the return command means, the control means operates the drive source in the reverse direction.

  In the present invention, the drive source is an electromagnetic solenoid, and when it has a return command means for issuing a return signal, the control means stops the operation of the electromagnetic solenoid when the return command signal is input from the return command means. It is characterized by that.

  These conveying member releasing devices have an image transfer unit and a pair of conveying members that are movable in a direction in which one of them is in contact with or separated from the other and that conveys the sheet to the image transferring unit when approaching. You may apply to.

  As an image forming apparatus, an image transfer unit is configured by a printing drum on which a plate used for printing is wound and a printing pressure member that sandwiches a sheet between the outer peripheral surface of the printing drum. It is a feature.

According to the present invention, a pair of transport members for sandwiching and transporting a sheet, an arm member for enabling one of the transport members to move toward or away from the other, and the arm member A mechanism having a cam for swinging, a detection means for detecting paper jam, and when the paper jam is detected by the detection means, one of the conveying members is moved relative to the other without operating the cam. Since the moving means for moving the arm member in the separating direction and the drive source for driving the moving means are provided, when the paper jam is detected by the detecting means, the moving means operates to move the arm member. to move in the direction in which one can be spaced from the other of the conveying member by, without sheet is fed in the sheet conveyance direction by the pair of conveying members, there is no condition deterioration of the paper jam, The jam releasing operation of the paper can be easily performed.

  FIG. 1 shows a stencil printing apparatus which is a printing apparatus as an image forming apparatus according to an embodiment of the present invention. In the figure, the stencil printing apparatus is a stencil printing as an image transfer unit that performs stencil printing on a paper feeding unit 3 that feeds paper 2 to the apparatus body 1 and paper 2 fed from the paper feeding unit 3. A unit 4, a paper discharge unit 6 for discharging the paper 2 for which the image has been applied to the outside of the apparatus, a release device 70, and a control means 50 for controlling the entire device are provided.

An image reading unit 40 is disposed on the upper part of the apparatus main body 1. The image reading unit 40 is a movable scanning unit 41A that reads an image on the document 38, and an image sensor 41 such as a CCD to which image data scanned by the scanning unit 41A is input.
This is a known configuration having B and the like.

  The paper feed unit 3 includes a paper feed tray 10 on which a large number of papers 2 are stacked, a paper feed roller 11 that feeds the paper 2 on the paper feed tray 10 from the uppermost one by one, and a paper feed roller 11. It has a pair of registration rollers 12 as a pair of conveying members for temporarily feeding the fed paper 2 and feeding it to the stencil printing unit 4 at a predetermined timing.

  A paper transport path 26 is formed between the paper feed roller 11 and the stencil printing unit 4. The registration roller pair 12 is made of a rubber drive roller 12A as an elastic member that faces the paper conveyance path 26 from below and the drive roller 12A that faces the paper conveyance path 26 from above. It is comprised with the resin-made driven roller 12B which touches. The driven roller 12B may be a metal roller. The drive roller 12A is configured to be rotated by a stepping motor 28 serving as a drive motor. The driven roller 12B is driven to rotate by contacting the outer peripheral surface of the driving roller 12A when the driving roller 12A rotates. A jam detection sensor 27 serving as a conveyance abnormality detecting means for detecting a paper jam as an example of a conveyance abnormality and outputting a paper jam signal is detected in the paper conveyance path 26 positioned between the registration roller pair 12 and the stencil printing unit 4. It is arranged.

  A plate making unit 7 is disposed on the upper right side of the stencil printing unit 4. The plate making unit 7 includes a master accommodating unit 14 that accommodates a master 13 wound in a roll shape, a thermal head 15 and a platen conveying member 16 that are disposed downstream of the master accommodating unit 14 in the master conveying direction, and the master 13. It has a master cutting means 17 for cutting, a master conveying / conveying member pair 18 for nipping and conveying the master, and the like. The plate making unit 7 forms a perforated plate making image on the master 13, and then transports a plate making master 19 to be used for printing toward the stencil printing unit 4.

  The stencil printing unit 4 includes a printing drum 20 made of a porous cylindrical body that winds the master-made master 19 made by the plate-making unit 7 on its outer peripheral surface 20a, and a contact (not shown) on the outer peripheral surface of the printing drum 20. It is provided between the press roller 22 as a printing pressure member which is provided so as to be freely contacted and separated by a separating mechanism and sandwiches the sheet 2 with the outer peripheral surface 20 a of the printing drum 20. A known pressure cylinder may be used instead of the press roller 22 as a printing pressure member.

  Inside the printing drum 20, an ink supply means 9 having an ink conveying member 21 and a doctor conveying member 8 is disposed. The stencil printing unit 4 presses the paper 2 fed from the paper feeding unit 3 against the plate-making master 19 wound on the outer peripheral surface 20 a of the printing drum 20 by the press roller 22, thereby from the ink supply unit 9. The supplied ink is transferred onto the paper 2 to form a stencil image on the paper 2. On the upper left side of the printing drum 20, a plate discharging device (not shown) that peels and discards the used master-making master 19 from the outer peripheral surface of the printing drum 20 is disposed. The printing drum 20 is driven to rotate in the clockwise direction in FIG.

  In this embodiment, the printing drum 20 and the registration roller pair 12 are driven separately. However, the main motor 29 is connected to the driving roller 12A via a known drive transmission mechanism such as a gear or a pulley. Thus, a form in which both are driven may be employed.

  The paper discharge unit 6 is provided with a peeling claw 23 for peeling the paper 2 stuck to the plate-making master 19 on the printing drum 20 by the viscosity of the ink, and the paper 2 that has passed through the stencil printing unit 4 by the suction force of the suction fan 24. A belt conveyance unit 25 for sucking and conveying, and a paper discharge tray 35 for stacking the sheets 2 delivered by the belt conveying unit 25 are provided.

  2 and 3, the release device 70 is connected to the contact / separation means 71 for contacting / separating the driven roller 12B with respect to the driving roller 12A, and the contact / separation means 71 The operation includes moving means 72 for individually moving the driven roller 12B in the separating direction.

The contact / separation means 72 includes a pair of arm members 73A and 73B as swing members that support the driven roller 12B in a direction in which the driven roller 12B is contacted and separated from the drive roller 12A, and a contact direction of the arm members 73A and 73B with the drive roller 12A The arm member 73A, 73B is displaced in the contact / separation direction by rotationally engaging with the one arm member 7 3 A and a pair of tension coil springs 74A, 74B as a biasing member and a means for imparting a movement habit to the arm And a cam member 75.

  As shown in FIG. 2, the driven roller 12 </ b> B is a plurality of rollers that are rotatably supported at intervals on a support shaft 76 that extends in the paper width direction Y orthogonal to the paper transport direction X in plan view. The driving roller 12 </ b> A is a plurality of rollers rotatably supported at intervals on a support shaft 77 extending in the paper width direction Y, and each roller is disposed so as to face each driven roller. The drive shaft 77 is connected to the stepping motor 28 via a drive transmission mechanism (not shown), and is driven to rotate when the stepping motor 28 is driven.

Driven roller 12B, by fixing the ends of the support shaft 76 arm member 73A, the one end 73a side of the 73B, the arm member 73A, is attached to 73B. The other ends 73b of the arm members 73A and 73B are attached to a rotation shaft 78 rotatably supported by a main body frame (not shown) so that the driven roller 12B can be brought into contact with and separated from the drive roller 12A. One end of each of the tension coil springs 74A and 74B is locked to one end of each of the arm members 73A and 73B, and the other end is locked to a spring hook 79 provided on a frame (not shown). The outer peripheral surface is in pressure contact with the outer peripheral surface of the drive roller 12a.

  A proximal end 81b of a cam follower arm 81 having a roller 80 rotatably supported by a distal end 81a is fixed to an end 78a of the rotation shaft 78 so as to rotate integrally with the arm members 73A and 73B. It is configured. The cam member 75 is connected to a drive transmission mechanism (not shown) of the printing drum 20 so as to rotate around the shaft 82 in synchronization with the rotation of the printing drum 20 when the main motor 29 is driven. In the present embodiment, the cam member 75 is configured to make one rotation similarly when the printing drum 20 makes one rotation.

  The cam member 75 has an outer peripheral surface 75a disposed at a position facing the roller 80 of the cam follower arm 81, and the roller 80 is in pressure contact with the urging force of the tension coil springs 74A and 74B. The shape of the outer peripheral surface 75a of the cam member 75 is such that the driven roller 12B is driven roller as shown in FIG. 3 until the paper 2 fed from the registration roller pair 12 is sandwiched between the printing drum 20 and the press roller 22. When the leading end of the sheet is nipped and moved to the separation position as shown in FIG. 4, the driven roller 12B is shown in FIG. 3 when the next sheet 2 is fed. The cam profile indicates the contact position. When the driven roller 12B occupies the contact position, it is pressed against the driving roller 12A by the urging force of each tension coil spring.

  The moving means 72 includes a pin 85 erected on the rotation shaft 78, a link member 86 having one end 86a connected to the arm members 73A and 73B via the pin 85 and the rotation shaft 78, and a link member 86. The release motor 87 is connected to the other end 86b side and serves as a drive source for moving the link member 86 in a direction in which the arm members 73A and 73b are moved in the separating direction (hereinafter referred to as “release direction”).

  A long hole 89 extending in the release direction is formed at one end 86a of the link member 86, and the tip of the pin 85 is loosely fitted. The reason why the pin 85 is loosely fitted and supported by the elongated hole 89 is that the link member 86 is not moved when the arm members 73A and 73B are rotated by the cam member 75.

  The release motor 87 is a stepping motor or a DC motor, and a worm gear 88 is attached to the output shaft thereof. The worm gear 88 meshes with a tooth portion 90 formed at the other end 86 b of the link member 86. Therefore, for example, when the drive motor 87 is driven in FIG. 3 and the worm gear 88 is rotated in the clockwise direction, the link member 86 is moved to the right in the release direction in the drawing.

  The control means 50 is configured by a known computer having a configuration such as a CPU, a ROM, a RAM, and a timer. The control means 50 includes a paper feed system drive unit 42 as a drive source for the paper feed unit 3 including the stepping motor 18, a reading system drive unit 43 including a drive source for the entire image reading unit 40 including the main motor 29, and plate making. A plate making system driving unit 44 having a driving source for the entire unit 7, a printing system driving unit 45 having a driving source for the entire image printing unit 4, a paper discharging system driving unit 46 having a driving source for the belt conveying unit 25, A release motor 87 is connected to the output side.

  The jam detection sensor 27, the image reading unit 40, and the operation panel 60 are connected to the input side of the control unit 50. The operation panel 60 is provided with a release switch key 61 as a release command means for issuing a release command signal and a return switch key 62 as a return command means for issuing a return signal. The release switch key 61 is a switch that is operated when the operator wants to separate the driven roller 12B. The return switch key 62 is used when the operator wants to return the driven roller 12B to the contact state when the jam processing is completed. It is a switch to operate.

  The control unit 50 appropriately controls each drive unit to control the operation of the entire stencil printing performed on the apparatus main body 1 side, and releases the link member 86 when a paper jam detection signal is input from the jam detection sensor 27. The release motor 87 is operated in the direction of moving in the direction, and the operation of the other devices is stopped. The control means 50 also operates the release motor 87 in a direction to move the link member 86 in the release direction even when a release command signal is input from the release switch key 61. When the return switch key 61 is operated and a return command signal is input, the control means 50 drives the release motor 87 in the reverse direction in a direction to move the link member 86 to an initial position opposite to the release direction.

  Next, a basic operation of the image forming apparatus will be described, and then a cancellation operation at the time of jam detection will be described. In this embodiment, it is assumed that the master 19 that has already been made is wound around the outer peripheral surface 20a of the printing drum 20, and the printing operation will be described.

  When an operator inputs the number of prints with a numeric keypad (not shown) of the operation panel 60 and a known print start key is activated, the paper feed roller 11 rotates to feed paper by driving the paper feed system drive unit 42. The first sheet 2 is fed from the tray 10. The printing drum 20 is driven to rotate at a rotational peripheral speed corresponding to the set printing speed by driving the printing system driving unit 45. Although the driven roller 12B is placed at the contact position shown in FIG. 3, the stepping motor 28 is not driven, so that the leading edge of the fed paper 2 is sandwiched between the registration roller pair 12. As the printing drum 20 rotates, the cam member 75 also rotates, and the stepping motor 28 is driven at the registration timing. Therefore, the sheet 2 is timed by the registration roller pair 12 and sent to the stencil printing unit 4 formed between the printing drum 20 and the press roller 22, and the stencil printing is performed by the press roller 22 swinging. The image is transferred.

  The cam follower arm 81 is gradually pushed up in the separation direction as shown in FIG. 4 due to the characteristics of the cam member 75 that the leading edge of the paper 2 reaches the stencil printing unit 4 and is sandwiched between the printing drum 20 and the press roller 22. With this movement, the rotation shaft rotates clockwise in the figure. For this reason, the arm members 73A and 73B integrated with the rotation shaft 78 also move in the separation direction as the rotation of the cam member 75 proceeds, and finally the driven roller 12B is engaged with the drive roller 12A.

  For this reason, the fed paper P is free from resistance due to the clamping of the registration roller pair 12. For this reason, the paper 2 is conveyed and fed according to the rotational peripheral speed of the printing drum 20. When the arm members 73A and 73B rotate, the pin 85 moves. However, since the movement of the pin 85 is absorbed by the elongated hole 89, the link member 86 does not move in the release direction, and the release motor 87 is loaded. It does not take. The sheet 2 conveyed to the stencil printing unit 4 is nipped between the printing drum 20 and the press roller 22 to transfer (print) an image of the master 19 that has been made, and reaches the belt conveying unit 25 to be sucked and conveyed. Then, the paper is discharged to the paper discharge tray 35. Such an operation is continued while the set number of printed sheets is reached, and the apparatus stops when the number of printed sheets is reached.

  When a jam detection signal is output from the jam detection sensor 27 during the operation of the image forming apparatus, the control unit 50 drives the release motor 87 and stops the operation of other apparatuses. When the release motor 87 is driven, the link member 86 moves in the release direction (rightward in the figure) as shown in FIG. By this movement, the pin 85 loosely fitted in the elongated hole 89 is pulled in the same direction, so that the rotation shaft 78 is independent of the position of the cam member 75. The clockwise direction, that is, the cam follower arm 81 is displaced in a direction in which the roller 80 is separated from the outer peripheral surface 75 a of the cam member 75. For this reason, the arm members 73A and 73B are urged by the tension coil springs 74A and 74B to rotate in the clockwise direction in the drawing, and the driven roller 12B is held in the separated state.

  As described above, when the occurrence of a jam is detected, the apparatus immediately stops, and the arm members 73A and 73B and the cam follower arm 81 are moved in the separating direction by the driving of the release motor 87. Regardless of this, the pressure contact state between the driven roller 12B and the driving roller 12A can be immediately released. Therefore, the sheet 2 is not fed in the sheet conveyance direction X by the registration roller pair 12 in the pressure contact state, the sheet jam condition is not deteriorated, and the jam release operation of the sheet 2 can be easily performed.

  Further, since the link member 86 and the release motor 87 are engaged with each other by the tooth portion 90 and the worm gear 88, even if the power of the release motor 87 is cut off during the jam release operation by the operator, the release motor 87 and the gear engagement portion. Therefore, the arm members 73A and 73B and the cam follower arm 81 do not return to the contact direction by the urging force of the tension coil springs 74A and 74B, and the jam release operation of the sheet 2 can be performed more easily.

  On the other hand, when the driven roller 12B is returned to the contact position with the driving roller 12A, the return switch key 62 is operated. When this operation is performed, the release motor 87 rotates in a direction opposite to that at the time of release, and the link member 86 moves in a direction opposite to the release direction (right side in the figure) (left side in the figure) in FIG. By this movement, the pin 85 loosely fitted in the elongated hole 89 is pushed in the same direction, so that the rotating shaft 78 moves counterclockwise, that is, the cam follower arm 81 brings the roller 80 close to the outer peripheral surface 75 a of the cam member 75. It is displaced in the direction to be For this reason, the arm members 73A and 73B are coupled with the urging forces of the tension coil springs 74A and 74B to rotate counterclockwise in the drawing, and the driven roller 12B is brought into contact with the drive roller 12A.

  Depending on the usage form of the stencil printing apparatus, a non-use period can be assumed. In such a case, if the driven roller 12B is kept in contact with the drive roller 12A, there is a concern about roller deformation due to the urging force of the tension coil springs 74A and 74B.

  In such a case, when the operator operates the release switch key 61, a release command signal is issued. When this signal is input to the control means 50, the release motor 87 is driven, and the link member 86 moves in the release direction (rightward in the figure) as shown in FIG. By this movement, the pin 85 loosely fitted in the elongated hole 89 is pulled in the same direction, so that the rotation shaft 78 is independent of the position of the cam member 75. The clockwise direction, that is, the cam follower arm 81 is displaced in a direction in which the roller 80 is separated from the outer peripheral surface 75 a of the cam member 75. For this reason, the arm members 73A and 73B are urged by the tension coil springs 74A and 74B to rotate in the clockwise direction in the drawing, and the driven roller 12B is held in the separated state. Thus, even if the operator arbitrarily operates the release switch key 61, the pressure contact state between the driven roller 12B and the drive roller 12A can be immediately released regardless of the position and state of the cam member 75. The registration roller pair 12 does not feed the paper 2 in the paper transport direction X, and the paper jam condition is not deteriorated, so that the paper 2 can be easily released from the jam.

  FIG. 7 shows a form in which an electromagnetic solenoid 97 is used as a drive source for the moving means 72. The configuration is the same as that shown in FIG. 2 except that the drive source is changed. The electromagnetic solenoid 97 is a pull type that pulls in the movable piece 97 a when the electromagnetic solenoid 97 is in an operating state, and the movable piece 97 a is pin-coupled to the other end 86 b of the link member 86. The movable piece 97a may be directly coupled to the pin 85 without using the link member 86. In this case, a long hole 89 shown in FIG. 3 may be formed in the movable piece 97a.

  FIG. 8 shows the control means 50 </ b> A for connecting the electromagnetic solenoid 97. The basic configuration and function are the same as those of the control means 50. The difference from the control means 50 is that when the jam detection information is inputted from the jam detection sensor 27 and when the release command signal is inputted from the release switch key 61, the electromagnetic solenoid 97 is operated and the return switch key 62 is operated. When the return command signal is input, the operation of the electromagnetic solenoid 97 is stopped.

  When such a control means 50A is used, when a jam detection signal is output from the jam detection sensor 27, the electromagnetic solenoid 97 is activated and the operation of other devices is stopped. When the electromagnetic solenoid 97 is actuated, the link member 86 moves in the releasing direction (rightward in the figure) as shown in FIG. 7, and the pin 85 loosely fitted in the elongated hole 89 is pulled in the same direction. For this reason, the rotation shaft 78 is independent of the position of the cam member 75. The clockwise direction, that is, the cam follower arm 81 is displaced in a direction in which the roller 80 is separated from the outer peripheral surface 75 a of the cam member 75. For this reason, the arm members 73A and 73B are urged by the tension coil springs 74A and 74B to rotate in the clockwise direction in the drawing, and the driven roller 12B is held in the separated state.

  As described above, when the occurrence of a jam is detected, the apparatus immediately stops, and the arm members 73A and 73B and the cam follower arm 81 are moved in the separating direction by the operation of the electromagnetic solenoid 97. Regardless of this, the pressure contact state between the driven roller 12B and the driving roller 12A can be immediately released. Therefore, the sheet 2 is not fed in the sheet conveyance direction X by the registration roller pair 12 in the pressure contact state, the sheet jam condition is not deteriorated, and the jam release operation of the sheet 2 can be easily performed.

  When returning the driven roller 12B to the contact position with the driving roller 12A, the return switch key 62 is operated. When this operation is performed, the electromagnetic solenoid 97 is turned off. At this time, the urging forces of the tension coil springs 74A and 74B and the weights of the arms and the rollers act on the link member 86, so that the coil member moves in the release direction (right side in the figure) and the reverse direction (left side in the figure) in FIG. By this movement, the pin 85 loosely fitted in the elongated hole 89 is pushed in the same direction, so that the rotating shaft 78 moves counterclockwise, that is, the cam follower arm 81 brings the roller 80 close to the outer peripheral surface 75 a of the cam member 75. It is displaced in the direction to be For this reason, the arm members 73A and 73B are coupled with the urging forces of the tension coil springs 74A and 74B to rotate counterclockwise in the drawing, and the driven roller 12B is brought into contact with the drive roller 12A. If the driven roller 12B is arbitrarily held away from the drive roller 12A, the operator may operate the release switch key 61 as described above.

  In the above embodiment, the release device 70 is applied to the registration roller pair 12 which is an example of a conveyance member. However, the conveyance member to be applied is not limited to the registration roller pair 12, and the paper 2 is nipped and conveyed. It can be applied to all conveying members. Further, the conveying member is not limited to a roller pair. For example, the driving side is a belt member and the driven side is in contact with the belt member, preferably a combination of roller members that are in pressure contact, or the driving side and the driven side are in contact or pressure contact with each other. You may apply to a belt member. The form of the conveying member to which the release member 70 is applied can be applied to a case where both of the conveying members facing each other are not driven or both are driven.

  In the above embodiment, the stencil printing apparatus which is one form of the printing apparatus is illustrated as the image forming apparatus including the conveying member to which the release device 70 is applied. However, the printing apparatus to be applied is not limited to the stencil printing apparatus. Absent. The image forming apparatus to which the release device 70 is applied is not limited to a printing apparatus, and a drum-like or belt-like photoconductor as an image carrier on which a toner image is carried, and the photoconductor formed on the photoconductor. Even if it is applied to a pair of registrationless rollers or other conveying members arranged in a well-known electrophotographic image forming apparatus in which an image transfer unit is constituted by a roller or a belt-like transfer member for transferring a toner image to a sheet. An effect equivalent to that of this embodiment can be obtained.

1 is a schematic front view of an image forming apparatus according to an embodiment of the present invention. It is a top view which shows schematic structure of a cancellation | release apparatus. It is an expanded sectional view which shows the structure of a cancellation | release apparatus. It is an expanded sectional view which shows cancellation | release operation | movement of the conveyance member by a cancellation | release apparatus. It is an expanded sectional view which shows cancellation | release operation | movement of the conveyance member by a moving means. It is a block diagram which shows the connection relation of a control means and the component connected to it. It is a top view which shows schematic structure of the cancellation | release apparatus from which the cancellation | release means and movement means shown in FIG. 3 differ. It is a block diagram which shows another connection of a control means, and the connection relation of the component connected to it.

Explanation of symbols

2 Paper 4 Image transfer unit 12 Pair of conveying members 12B One conveying member 12A The other conveying member 19 Plate 20 Printing drum 20a Outer peripheral surface of printing drum 22 Printing pressure member 50 Control means 70 Conveying member release device 71 Contacting / separating means 72 Movement Means 73A, 73B Oscillating members 74A, 74B Means for imparting movement behavior 75 Cam member 86 Link member 86a One end of link member 86b Other end of link member 87 Drive source 61 Release command means 62 Return command means 97 Electromagnetic solenoid

Claims (7)

A pair of conveying members for nipping and conveying the paper;
An arm member for movable in a direction between approaching or away one of said conveying member with respect to the other,
A mechanism having a cam for swinging the arm member, a detection means for detecting paper jamming,
Moving means for moving the arm member in a direction to separate one of the conveying members from the other without operating the cam when paper jam is detected by the detecting means;
A conveying member releasing device comprising: a driving source for driving the moving means. In the conveyance member cancellation | release apparatus of Claim 1,
A conveying member releasing apparatus comprising: a control unit that operates the drive source when a paper jam detection signal is input from the detection unit. In the conveyance member cancellation | release apparatus of Claim 2,
A release command means for issuing a release command signal;
The conveying member releasing device, wherein the control means operates the drive source when a release command signal is input from the release command means. In the conveyance member cancellation | release apparatus of Claim 3,
Having a return command means for issuing a return signal;
The transporting member releasing device, wherein the control means operates the drive source in the reverse direction when a return command signal is input from the return command means. In the conveyance member cancellation | release apparatus of Claim 3,
The drive source is an electromagnetic solenoid;
Having a return command means for issuing a return signal;
The transport member releasing device, wherein the control means stops the operation of the electromagnetic solenoid when a return command signal is input from the return command means. In an image forming apparatus comprising: an image transfer unit; and a pair of conveying members that are movable in a direction in which one side is in contact with or separated from the other and that sandwiches a sheet when approaching and conveys the sheet to the image transfer unit.
An image forming apparatus comprising the conveying member releasing device according to claim 1 as a releasing unit for the pair of conveying members. The image forming apparatus according to claim 6.
The image transfer unit is composed of a printing drum around which a plate used for printing is wound, and a printing pressure member that sandwiches the paper between the outer peripheral surface of the printing drum. Forming equipment.

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