JP2016098087A - Sheet conveyance device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet conveyance device capable of surely conveying and removing a remaining sheet with a simple operation even when conveyance resistance of the remaining sheet is high because the remaining sheet cannot be surely conveyed due to slips of conveying rollers and the sheet and jam processing becomes complicated for a long time when the conveyance resistance of the remaining sheet is high when a driving motor conveys the remaining sheet stopped over a plurality of different conveying rollers up to a take-out possible position by manually rotating a conveying roller on a downstream side.SOLUTION: A contact pressure of a driven roller 63 which is brought into pressure contact with a driving roller 62 of a pair of conveying rollers 61 is increased in accordance with an operation during jam processing so as to enhance conveyance force of the pair of conveying rollers 61 when manually rotated. Accordingly, a remaining sheet having high conveyance resistance is surely conveyed to a take-out possible position.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sheet conveying apparatus that conveys a sheet and an image forming apparatus including the sheet conveying apparatus.

  An image forming apparatus such as a copying machine or a printer includes a sheet conveying apparatus that conveys a sheet stored in a sheet storing unit along a conveying path. On the sheet conveyed by the sheet conveying apparatus, an image is formed by the image forming unit during conveyance on the conveyance path.

  As a sheet conveying apparatus, a configuration in which a plurality of conveying roller pairs are arranged along a conveying path and sheets are sequentially conveyed by the conveying roller pair is widely used. In the sheet conveying apparatus, when a sheet remains in the conveying path due to a jam or the like, it is necessary to remove the sheet from the conveying path.

  Japanese Patent Application Laid-Open No. 2004-228561 describes a sheet conveying apparatus in which an operation knob that drives a pair of conveying rollers is manually rotated to convey a sheet remaining in a conveying path to a position where it can be removed.

Japanese Patent Laid-Open No. 58-21725

  However, even if the operation knob is operated to rotate the conveyance roller pair, slip may occur between the conveyance roller pair and the sheet. For example, when the sheet remaining in the conveyance path stops while being sandwiched between two conveyance roller pairs, even if one conveyance roller pair is rotated by the operation knob, the sheet is rotated by the resistance of the other conveyance roller pair. Slip occurs between the pair of conveying rollers and the staying sheet. If slip occurs between the rotated pair of transport rollers and the staying sheet, it is difficult to remove the staying sheet because the sheet cannot be moved using the operation knob.

  An object of the present invention is to provide a sheet conveying apparatus capable of conveying and removing a remaining sheet by a simple operation.

  The present invention provides a conveying roller pair for conveying a sheet, a conveying path for guiding a sheet conveyed by the conveying roller pair, an operating means for manually rotating the conveying roller pair, and a sheet remaining in the conveying path. The sheet conveying apparatus includes an increasing unit that increases the pressure contact force of the pair of conveying rollers in accordance with the removing operation.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the sheet conveying apparatus which can remove a residual sheet reliably.

Explanatory drawing of the inversion conveyance part of 1st Embodiment. 1 is a schematic diagram of a digital printer according to a first embodiment. FIG. 3 is a control block diagram of the digital printer of the first embodiment. FIG. 3 is an operation explanatory diagram of the digital printer of the first embodiment. FIG. 3 is a schematic diagram of a conveyance roller pair according to the first embodiment. Explanatory drawing of the inversion conveyance part of 2nd Embodiment. Explanatory drawing of the inversion conveyance part of 3rd Embodiment.

(First embodiment)
FIG. 2 is a schematic diagram of an image forming apparatus including the sheet conveying device according to the first embodiment of the present invention. The image forming apparatus shown in FIG. 2 is an electrophotographic digital printer 10 that forms a toner image on a sheet.

  The digital printer 10 includes an image forming unit 11 that forms a toner image on the image carrier 1 and a sheet storage unit 12. The digital printer 10 further includes a sheet conveying apparatus including a paper feeding unit 13, a pre-registration conveyance unit 14, a transfer conveyance unit 15, a paper discharge conveyance unit 16, a reverse conveyance unit 17, and a double-side conveyance unit 18.

  The sheet S stored in the sheet storage unit 12 is fed by the sheet feeding unit 13 and conveyed to the transfer conveyance unit 15 via the pre-registration conveyance unit 14. The transfer conveyance unit 15 includes a registration roller pair 21, a transfer conveyance device 22, and a fixing device 23, and transfers and fixes a toner image while conveying the sheet S. The image forming unit 11 and the transfer conveyance unit 15 constitute an image forming unit that forms an image on a sheet.

  The paper discharge conveyance unit 16 switches the conveyance path with the paper discharge switching flapper 24 and conveys the sheet S to the outside of the machine (in the direction of arrow A) or the reverse conveyance unit 17 (in the direction of arrow B). The reverse conveyance unit 17 reverses the conveyance direction after drawing the sheet S into the inside, switches the path by the paper discharge switching flapper 24 and the reverse switching flapper 25, and passes the sheet S through the paper discharge conveyance unit 16. It is transported outside the machine (in the direction of arrow C) or to the double-sided transport unit 18 (in the direction of arrow D). The sheet S conveyed to the double-sided conveyance unit 18 is conveyed again to the transfer conveyance unit 15 via the pre-registration conveyance unit 14, and an image is formed on the back surface.

  Further, the digital printer 10 detects a control unit 101, a monitoring sensor 102 for detecting voltages and temperatures of each part of the electrophotographic process system apparatus such as the image forming unit 11, and a sheet passing timing and position in each sheet conveying apparatus. The conveyance sensor 103 is provided. The control unit 101 controls operations of the sheet conveyance system apparatus and the electrophotographic process system apparatus based on detection signals from the monitoring sensor 102 and the conveyance sensor 103 in addition to the image forming signal. FIG. 3 shows a control system block diagram of the digital printer 10.

  Further, the control unit 101 determines an abnormality of each part of the apparatus and a jam of the sheet from the detection results of the monitoring sensor 102 and the conveyance sensor 103, and performs a return process according to the state and stops the sheet conveyance and the image forming operation. Process.

  The sheet remaining in the conveyance path due to the stop of the conveyance operation due to a jam or an abnormality of the apparatus is removed by opening the conveyance path.

  Here, the configuration related to the jam processing in the digital printer 10 for removing the residual sheet by opening the conveyance path for guiding the sheet will be described.

  The sheet storage unit 12, the transfer conveyance unit 15, and the double-side conveyance unit 18 are supported so as to be able to be pulled out forward (in a direction perpendicular to the paper surface in FIG. 2) of the digital printer 10 through a slide rail (not shown). Drawer unit. In order to open the conveyance path of the drawer unit, it is necessary to pull out the drawer unit from the main body of the digital printer 10. On the other hand, the paper feeding unit 13, the pre-registration conveyance unit 14, the paper discharge conveyance unit 16, and the reverse conveyance unit 17 are fixed units fixed to the apparatus main body of the digital printer 10. In order to remove the sheet staying in each fixed unit, the conveyance path is opened by rotating the right door 30 integrated with a part of the conveyance path or the movable guides 31 to 35 supported rotatably. FIG. 4 is a schematic view of the digital printer 10 in a state where the right door 30 and the movable guides 31 to 35 are rotated to open the conveyance path.

  Depending on the stop timing of the jamming or abnormal conveyance operation, the remaining sheet may stop across the conveyance path of the drawer unit and the conveyance path of the fixed unit. When the drawer unit is pulled out with the sheet straddling the conveyance path of the drawer unit and the conveyance path of the fixed unit, the parts of the device are damaged by the sheet or the sheet is broken and a piece of paper is generated. May remain in the transport path. Therefore, in the digital printer 10, in order to prevent damage to the components of the apparatus and the generation of paper pieces, first, the conveyance path on the fixed unit side is opened, and the remaining sheet that extends over both conveyance paths is removed.

  However, like the sheets S1 and S3 shown in FIG. 4, the remaining sheet stopped across the conveyance path of the drawer unit and the conveyance path of the fixed unit opens the conveyance path (rotates the right door 30 and the movable guides 31 to 35). ) It may be in a position that cannot be removed by just doing. In such a case, the conveyance roller pair is manually rotated, and the remaining sheet is conveyed to a removable position in the fixed unit and then removed.

  The sheet S1 is nipped and stopped by the pair of conveyance rollers 41 of the pre-registration conveyance unit 14 and the conveyance roller pair 51 of the double-sided conveyance unit 18. The sheet S3 is nipped and stopped by the conveyance roller pair 61 of the reverse conveyance unit 17 and the conveyance roller pairs 54 and 55 of the double-sided conveyance unit 18, respectively.

  In addition to the drive motors M1 and M2, the pre-registration conveyance unit 14 and the reverse conveyance unit 17 are provided with operation means for manually rotating (driving) the conveyance roller pair 41 or the conveyance roller pair 61. . The sheet S1 is conveyed in the direction of arrow F to the removable position E by the conveyance roller pair 41 that is manually rotated. The sheet S3 is conveyed in the direction of the arrow H to the removable position G by the conveyance roller pair 61 that is manually rotated. The configuration and operation of the operating means for manually rotating the transport roller pair 61 will be described in detail later.

  The double-sided conveyance unit 18 includes conveyance roller pairs 51 to 55, a drive motor M3, and a drive transmission unit (not shown) that transmits the drive from the drive motor M3 to the conveyance roller pairs 51 to 55. The drive motor M3 that drives the conveyance roller pairs 51 to 55 is a motor that is different from the drive motor M1 that is provided to drive the pre-registration conveyance unit 14. Each of the conveyance roller pairs 51 to 55 is connected to a drive transmission unit via a one-way clutch. The one-way clutch is set so that when the sheet sandwiched between the conveying roller pairs 51 to 55 is pulled out in the direction of arrow F in FIG. On the other hand, when the sheet sandwiched between the conveyance roller pairs 51 to 55 is pulled out in the direction of arrow H in FIG. 4, the conveyance transmission between the conveyance roller pairs 51 to 55 and the drive transmission unit remains connected. And the load of the drive M3 are added as resistance when the sheet is pulled out.

  Therefore, in the present embodiment, when the reversing conveyance unit 17 manually rotates the conveyance roller pair 61 to convey a sheet for jam processing, the following details are provided for increasing the pressure contact force of the conveyance roller pair 61. The increase means described is provided. Here, the pressure contact force of the conveyance roller pair 61 is a force in which one roller of the conveyance roller pair is in pressure contact with the other roller, and the conveyance force by which the conveyance roller pair 61 conveys a sheet by increasing the pressure contact force. Increase. That is, when the sheet is conveyed by manually rotating the conveyance roller pair 61, the larger the pressure contact force of the conveyance roller pair 61, the greater the force of feeding the sheet by the conveyance roller pair 61.

  By increasing the conveyance force of the conveyance roller pair 61 in this way, even when the load of the drive transmission unit of the double-side conveyance unit 18 or the drive motor M3 is a sheet conveyance resistance, the conveyance roller pair 61 causes the sheet S3 to be transferred. It can be reliably transported to the removable position G. That is, if the load of the drive transmission unit of the double-sided conveyance unit 18 or the drive motor M3 is a sheet conveyance resistance, the conveyance roller pair 61 and the sheet slip and convey even if the conveyance roller pair 61 is manually rotated. There is concern about the occurrence of problems that cannot be done. However, in the present embodiment, since the conveying force of the conveying roller pair 61 is increased by the increasing means, slip between the conveying roller pair 61 and the sheet is reduced, and the occurrence of the above problem is reduced.

  Below, the increase means with which the reverse conveyance part 17 was equipped is demonstrated in detail.

  First, FIG. 5 shows a schematic diagram of the conveying roller pair 61. The conveying roller pair 61 includes a driving roller 62 that rotates in response to driving from the driving motor M <b> 2 and a driven roller 63 that rotates following the driving roller 62. The driving roller 62 includes a conveying roller 62a that conveys a sheet, and a driving shaft 62b that is rotatably supported and rotates integrally with the conveying roller 62a. The driven roller 63 includes a biasing roller 63a that is biased with respect to the transport roller 62a, and a driven shaft 63b that rotates integrally with the biasing roller 63a.

  FIG. 1 shows details of the reverse conveyance unit 17 to which the conveyance roller pair 61 is attached. As described above with reference to FIG. 4, the reversing conveyance unit 17 is provided with movable guides 34 and 35 that can be opened and closed for jamming. FIG. 1A shows a state in which the movable guides 34 and 35 are closed, and FIG. 1B shows a state in which the movable guide 34 is opened and the conveyance path is opened.

  One end of the drive shaft 62b of the drive roller 62 rotatably supported is extended to the rear side of the rear plate 3 of the apparatus main body frame, and is connected to a drive motor M2 disposed behind the rear plate 3. The other end of the drive shaft 62b extends forward of the front plate 2 of the apparatus main body frame, and an operation knob 71 that is operated by the operator to rotate the transport roller pair 61 is fixed.

  The driven shaft 63b of the driven roller 63 is rotatably supported by the urging arms 73a and 73b. The urging arms 73a and 73b are rotatably supported by the arm shaft 72. One end of urging springs 75 a and 75 b is attached to the urging arms 73 a and 73 b, and the other end of the urging springs 75 a and 75 b is attached to hooks 74 a and 74 b fixed to the movable guide 34. That is, the urging arms 73a and 73b and the movable guide 34 are connected by the urging springs 75a and 75b.

  The urging springs 75a and 75b urge the driven roller 63a as one roller of the conveying roller pair 63 to the conveying roller 62a as the other roller via the urging arms 73a and 73b. The urging springs 75a and 75b are formed on the sheet so that the urging force of the urging roller 63a is optimal for sheet conveyance with the movable guide 34 closed, that is, the sheet is stably conveyed. It has been adjusted not to damage the image.

  The movable guide 34 is rotatably supported on the shaft 76. The movable guide 34 is provided with a handle portion 34a that protrudes forward of the front side plate 2 and serves as a protruding portion. When opening and closing the movable guide 34, the operator operates the handle portion 34 a to rotate the movable guide 34 around the shaft 76. As in the sheet S3 shown in FIG. 4, the remaining sheet at a position that cannot be removed simply by opening the conveyance path, the operation knob 71 is manually rotated after the movable guide 34 is opened and the conveyance path is opened. When the conveying roller pair 61 rotates in response to the rotational force from the operation knob 71, the conveying roller pair 61 conveys the sheet to a position where the sheet can be removed.

  Here, as shown in FIG. 1B, when the movable guide 34 is opened, the urging springs 75a and 75b extend to increase the tension, and accordingly, the urging force of the urging roller 63a against the conveying roller 62a is increased. To increase. Accordingly, the pressure contact force of the pair of conveyance rollers 61, that is, the conveyance force that is a force for conveying the sheet is increased. Therefore, like the sheet S3, a residual sheet having a large conveyance resistance due to the load of the drive transmission unit of the double-sided conveyance unit 18 and the drive motor M3 can be conveyed by the conveyance roller pair 61 with increased pressure contact force. That is, when the operation knob 71 is rotated and the sheet is conveyed by the conveying roller pair 61, there is no possibility that the sheet cannot be conveyed due to slippage between the conveying roller pair 61 and the sheet.

  In the present embodiment, the conveying roller in accordance with the operation of opening the movable guide 34 which is one of a series of jamming operations by the increasing means constituted by the biasing springs 75a and 75b, the movable guide 34 and the hooks 74a and 74b. The pressure contact force (conveyance force) of the pair 61 is increased. Therefore, it is possible to reliably remove the remaining sheet without increasing the number of steps for jam processing.

  In this embodiment, the urging force of the driven roller 63a is increased in conjunction with the opening of the movable guide 34. However, the urging force of the urging roller 63a is interlocked with other operations such as opening / closing of the door. The same effect can be obtained even if the value is increased.

(Second Embodiment)
FIG. 6A shows a sheet conveying apparatus according to the second embodiment of the present invention. The sheet conveying apparatus of the present embodiment is different from the first embodiment in that the sheet conveying apparatus includes a reverse conveying unit 80 having a different configuration for increasing the pressure contact force (conveying force) of the conveying roller pair. Components similar to those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof is omitted.

  In the reverse conveyance unit 80, the operation knob 71 is fixed to a fulcrum shaft 81 that is rotatably supported. On the fulcrum shaft 81, swing arms 82a and 82b as swing members are swingably supported, and the swing arms 82a and 82 are swingable about the rotation center (axial center) of the fulcrum shaft 81. is there. The swing arms 82a and 82b rotatably support the driven shaft 63b of the driven roller 63. Therefore, the driven roller 63 is supported so as to be swingable around the fulcrum shaft 81. Further, the driven roller 63 is urged toward the conveyance roller 62a by an urging force suitable for sheet conveyance by urging springs 83a and 83b engaged with the driven shaft 63b. The driven shaft 63b of the driven roller 63 is disposed downstream of the fulcrum shaft 81 in the direction in which the sheet is manually conveyed by the conveyance roller pair 61.

  On the fulcrum shaft 81, fulcrum gears 84a and 84b as first gears are integrally fixed at locations protruding on both sides of the conveyance path, and the driven shaft 63b is a second gear that meshes with the fulcrum gears 84a and 84b. Idler gears 85a and 85b are rotatably supported. The idler gears 85a and 85b and the drive gears 86a and 86b as third gears are set to have the number of teeth so that the gears mesh with each other at the position where the driven roller 63 is urged against the drive roller 62.

  FIG. 6B shows details of the drive train by each gear. As shown in FIG. 6B, in order to convey the sheet sandwiched by the conveyance roller pair 61 in the direction of arrow H, the operation knob 71 fixed to the fulcrum shaft 81 is rotated in the direction of arrow J to drive the drive gear. What is necessary is just to rotate 86a (86b) to the arrow L direction.

  When the fulcrum gear 84a (84b) is rotated in the direction of arrow J to transmit the drive to the drive gear 86a (86b), the driven shaft 63b is driven by the swing arm 82a (82b) according to the load torque of the drive shaft 62b. Receives a force in the direction opposite to the arrow H direction. Due to the moment about the fulcrum shaft 81 due to this force, when the conveyance roller pair 61 is manually rotated, the pressure contact force of the conveyance roller pair 61 can be increased according to the sheet conveyance resistance. As described above, in the reverse conveyance unit 80, during the jam processing, the moment generated in the driven shaft 63b increases as the sheet conveyance resistance increases, and the conveyance roller pair 61 can obtain a large pressure contact force (conveyance force). Therefore, a more reliable residual sheet removal operation can be performed.

  In the present embodiment, the operation knob 71 is fixed to the fulcrum shaft 81 that is rotatably supported. However, the operation knob may be provided at other locations such as the drive shaft 62b and the driven shaft 63b. Similar effects can be obtained as long as the biasing force of the driven roller 63 is increased by utilizing the action of the swing-supported gear train.

(Third embodiment)
FIG. 7A shows a sheet conveying apparatus according to a third embodiment of the present invention. The third embodiment is different from the first embodiment in that it has a reverse conveyance unit 90 having a different configuration for increasing the pressure contact force of the conveyance roller pair. The same configurations as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof is omitted.

  The reverse conveyance unit 90 includes an input shaft 91 and an idler shaft 92 that are rotatably supported. The input shaft 91 that rotates by receiving the rotational force from the operation knob 71 includes a drive pulley 91a as a first pulley that is integrally fixed at the center in the conveyance width direction. The idler shaft 92 includes a drive pulley 92a that is integrally fixed at the center in the conveyance width direction. The drive pulley 91 a and the drive pulley 92 a support the drive belt 93 and are connected to each other by the drive belt 93. An operation knob 71 is fixed to one end of the input shaft 91. An idler pulley 96 is rotatably supported on the driven shaft 63b, and the idler pulley 96 supports a drive belt 93. That is, the idler pulley 96 as the second pulley provided on the driven shaft 63 b is in contact with the outer periphery of the drive belt 93 and is driven by the drive belt 93.

  When the operation knob 71 is manually rotated, the input shaft 91 is rotated. The rotation of the input shaft 91 is transmitted to the idler shaft 92 by the drive belt 93. The idler shaft 92 is integrally provided with a driving pulley 92b at the end. Therefore, the rotation transmitted to the idler shaft 92 is transmitted to the drive pulley 95 that is integrally fixed to the drive roller shaft 62a via the drive belt 94.

  FIG. 7B shows details of a drive transmission path by the drive belts 93 and 94.

  As shown in FIG. 7B, the operation knob 71 fixed to the drive shaft 91 is rotated in order to convey the sheet sandwiched between the conveyance roller pair 61 in the arrow H direction by operating the operation knob 71. Thus, the rotation of the input shaft 91 is transmitted to the drive shaft 62b. At this time, the tension of the tension side region 97 of the driving belt 93 that receives the driving force from the driving pulley 91a and moves in the arrow N direction is increased according to the load torque of the driving shaft 62b. As the tension rises, the idler pulley 96 receives a force in the direction of arrow R from the drive belt 93, and the urging force of the driven roller 63 against the drive roller 62 increases.

  Therefore, in the reverse conveying unit 90, when the residual sheet is conveyed in the arrow H direction by operating the operation knob 71, the pressure contact force (conveying force) of the conveying roller pair 61 can be increased.

  In this embodiment, the drive belt 93 is provided at one place in the center in the conveyance width direction as an increase means for the driven roller 63, but the same effect can be obtained even when it is arranged at other positions or at a plurality of places. it can.

  In this embodiment, the driving belt 93 is used to increase the driven roller 63 using the load torque of the driving roller 62. However, other types of means can also be used that use the load torque of the driving roller 62. The same effect can be obtained.

  Further, although an electrophotographic image forming unit is shown as an example of an image forming unit that forms an image on a sheet, the present invention can also be applied to an image forming apparatus including an ink jet image forming unit.

61 Conveying roller pair 71 Operation knob 75a, 75b Energizing spring

Claims (8)

A pair of conveying rollers for conveying the sheet;
A conveyance path for guiding a sheet conveyed by the conveyance roller pair;
Operating means for manually rotating the pair of conveying rollers;
An increasing means for increasing the pressure contact force of the pair of transport rollers in accordance with the operation of removing the sheet remaining on the transport path;
A sheet conveying apparatus comprising: A guide that forms the transport path;
The sheet conveying apparatus according to claim 1, wherein the increasing unit increases a pressure contact force of the pair of conveying rollers in accordance with an operation of moving the guide so as to open the conveying path. The increasing means is
A swinging member that rotatably supports one of the pair of transport rollers and swings;
A biasing spring having one end attached to the swing member and the other end attached to the guide, and biasing the one roller to the other roller;
The sheet conveying apparatus according to claim 2, comprising:   The sheet conveying apparatus according to claim 1, wherein the increasing unit increases a pressure contact force of the pair of conveying rollers with rotation of the operation unit. The increasing means is
A first gear that rotates in response to a rotational force from the operating means;
A second gear that meshes with the first gear and is provided on the shaft of one of the pair of transport rollers, and is rotatably supported by a swinging member that swings about the rotation center of the first gear;
A third gear meshing with the second gear and provided on the shaft of the other roller of the pair of transport rollers;
The sheet conveying apparatus according to claim 4, further comprising: The increasing means is
A first pulley that rotates in response to a rotational force from the operating means;
A belt supported by the first pulley and rotating as the first pulley rotates;
A second pulley provided on the shaft of one of the pair of transport rollers, the outer periphery of the belt being in contact with the belt;
A third pulley that supports the belt and is coupled so as to transmit driving to the shaft of the other roller of the pair of transport rollers;
The sheet conveying apparatus according to claim 4, further comprising:   The conveying roller pair includes a driving roller and a driven roller biased by the driving roller, and the increasing means increases the pressing force of the conveying roller pair by increasing the biasing force of the driven roller. The sheet conveying apparatus according to claim 1, wherein the sheet conveying apparatus is a sheet conveying apparatus. A sheet conveying device according to any one of claims 1 to 7,
An image forming apparatus comprising: an image forming unit that forms an image on a sheet conveyed by the sheet conveying apparatus.

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