JP2012148863A - Sheet conveying system, image forming apparatus and image reading apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet conveying system conveying a sheet through a sheet conveyance passage between a first roller pair having rollers with a torque limiter installed and a second roller pair installed downstream in the sheet conveying direction than the first roller pair, while preventing a sheet from being stretched to generate large noise when a roller is stopped to cancel a loop of the sheet.SOLUTION: In the sheet conveying system including a paper feed roller 13, a separating roller 14 with a torque limiter, a conveying roller pair 21 and the like, first to third contact members 21a to 21c are provided that are protruded on the loop side where the sheet S is formed and each have a different timing to come in contact with a sheet S that reduces loops in a sheet conveyance passage from the paper feed roller 13 to the conveying roller pair 21, and first and second contact members 21a, 21b which come in contact with the sheet S earlier where loops are decreased are movably provided on the opposite side of the loop.

Description

  The present invention relates to a sheet conveying apparatus that conveys a sheet, and particularly has a feature that a sound when a loop (deflection) formed in a sheet on a sheet conveying path is eliminated can be reduced. .

  For example, copiers and printers are provided with a paper feed unit for feeding and carrying sheets stacked on a paper feed cassette into the machine. The paper feeding unit includes a pickup roller that takes out the uppermost sheet stacked on the paper feeding cassette, a paper feeding roller that pulls out the taken sheet from the paper feeding cassette to the sheet conveyance path, and a surface facing the paper feeding roller. And a separation roller that prevents two or more sheets from being overlapped and conveyed.

  A torque limiter is provided on the rotation shaft of the separation roller. When a rotational force exceeding the rotation limiting force of the torque limiter is applied to the separation roller, the separation roller rotates.

  Here, the rotation limit force of the torque limiter is set to be larger than the friction force between the sheets, but is set to be smaller than the friction force between the sheet and the separation roller. It is prevented from being conveyed by.

  In the sheet conveyance path, the peripheral speed of the conveyance roller pair positioned downstream in the sheet conveyance direction is set lower than that of the sheet feeding / separation roller pair composed of the sheet feeding roller and the separation roller, and the sheet is fed to the roller pair during conveyance. However, if such a speed difference is generated, a loop is formed on the sheet between the pair of sheet feeding / separating rollers and the pair of conveying rollers. become.

  However, it is difficult to secure a large space for forming the loop on the sheet conveyance path, and there is a limit to increasing the size of the loop. Therefore, when the loop becomes a certain size, the feed roller The rotation drive is stopped.

  FIG. 1 is a graph showing a change in peripheral speed and a change in the amount of loops formed on the sheet in the pair of feed roller and transport roller.

  This graph shows a circumferential speed change A of the paper feed roller, a circumferential speed change B of the conveying roller pair, and a loop amount change C of the sheet. The feed roller and transport roller pair are activated simultaneously, and when a predetermined amount of loop occurs in the sheet, that is, when a predetermined time elapses after the leading edge of the sheet enters the transport roller, the rotation stop control of the feed roller However, since the conveying roller pair continues to rotate even after this stop, the sheet loop amount rapidly decreases.

  Here, since the torque limiter of the separation roller becomes a resistance against the conveyance of the sheet, when the loop is eliminated, the sheet is tightly tensioned. Collides with the guide on the transport path and generates a loud noise.

  For this reason, in the image forming apparatus disclosed in Patent Document 1, in the secondary paper feeding after the loop is formed on the paper, the registration roller pair is driven before the transport roller pair, and the paper loop is formed. Until the problem is solved, the driving speed of the driving means for driving the pair of registration rollers and the pair of conveying rollers is controlled stepwise to suppress the sheet from being hit by the guide.

  In Patent Document 2 and Patent Document 3, when the paper enters the transport guide from the paper feed roller, a collision sound when the leading edge of the paper collides with the transport guide, and the rear edge of the paper from the paper feed roller. In order to suppress the collision sound when the rear edge of the paper collides with the conveyance guide when separated, the conveyance guide is provided with ribs, and the timing at which the leading edge or rear edge of the paper collides with the conveyance guide is made different for each rib. In order to suppress these collision sounds, there have been proposed.

JP 2005-154119 A Japanese Unexamined Patent Publication No. 63-42641 JP-A-2-90177

  However, since the image forming apparatus of Patent Document 1 increases the rotational speed of the registration roller pair in a stepwise manner, the rising speed of sheet conveyance by the registration roller pair is slowed, and the sheet conveyance efficiency is reduced. Thus, there is a drawback that the image forming speed is lowered. In addition, since the rotation control is performed on the registration roller or the like, there is a problem that the roller rotation mechanism is complicated.

  Further, in Patent Document 2 and Patent Document 3, when the paper enters the transport guide from the paper feed roller, a collision sound when the front end of the paper collides with the transport guide or the rear end of the paper is fed. Suppresses the collision noise when the trailing edge of the paper collides with the conveyance guide when it is separated from the roller, eliminating the loop generated in the sheet between the pair of feed / separation rollers and the conveyance roller pair It was not possible to eliminate the sound that was generated when being played.

  An object of the present invention is to solve the above-described problems in a sheet conveying apparatus that conveys a sheet using a roller with a torque limiter.

  That is, according to the present invention, when the loop in the sheet conveyed in the sheet conveying apparatus as described above is eliminated, it is easy to generate a loud noise due to the tight tension of the sheet due to the rotation limiting force of the torque limiter. It is possible to prevent appropriately by the configuration, and the sheet conveyance efficiency is not lowered, the image forming speed is not lowered, and further the sheet is appropriately conveyed so that the sheet is not wrinkled or bent. Let it be an issue.

  In order to solve the above-described problem, the sheet conveying apparatus of the present invention has a first roller pair having a roller to which a rotational limit force of a torque limiter is applied, and a downstream side of the first roller pair in the sheet conveying direction. The second roller pair disposed in the sheet, and the sheet conveying path between the first roller pair and the second roller pair protrudes toward the loop formed by the sheet and comes into contact with the sheet that reduces the loop. Two or more different contact members are provided, and at least a first contact member that first comes into contact with a sheet whose loop is reduced is provided so as to be movable on the side opposite to the loop.

  In this way, two or more contact members that protrude toward the loop formed by the sheet in the sheet conveyance path between the first roller pair and the second roller pair and have different timings to contact the sheet that reduces the loop are provided. When the sheet is provided, the sheet whose loop is reduced comes into contact with two or more contact members in sequence, and the sound generated when the sheet loop is eliminated is reduced. Further, since the rotation control for the registration roller or the like is not performed as in the prior art, the roller rotation mechanism does not become complicated, and the sheet conveyance efficiency does not decrease.

  Furthermore, when the first contact member that first contacts at least the sheet whose loop is reduced as described above is movably provided on the side opposite to the loop, the sheet whose loop is reduced becomes the first contact member. When the first contact member contacts the first contact member, the first contact member moves to the opposite side of the loop, and the sound generated when the sheet contacts the first contact member is also reduced. In addition, when the first contact member moves to the opposite side of the loop and is in the same state as the other contact members, the sheet properly contacts each contact member, so that the posture of the sheet is not disturbed, The sheet is appropriately conveyed, and the sheet is prevented from being wrinkled or folded.

  Here, in such a sheet conveying apparatus, it is preferable to provide each of the contact members along the sheet conveying direction. In this way, the sheet whose loop is reduced is appropriately conveyed while being in contact with each contact member provided in the sheet conveyance direction, and the sheet is further wrinkled or folded. It will be suppressed.

  Moreover, it is preferable to provide the 1st contact member which contacts a sheet | seat first in the center part of the direction which cross | intersects the conveyance direction of a sheet | seat. In this way, the sheet whose loop is reduced comes into contact with the first contact member at the center in the direction intersecting the sheet conveyance direction, and the first contact member moves to the opposite side of the loop, Thereafter, the sheet is appropriately conveyed along each contact member while being in contact with the first contact member and the other contact members on both sides thereof, and the occurrence of wrinkles and folds on the sheet is further suppressed. It becomes like this.

  Here, in providing the first contact member so as to first contact the sheet whose loop is to be reduced as described above, for example, a loop in which the first contact member is formed by the sheet from other contact members. It can be provided to project to the side. Alternatively, the first contact member can be provided from the other contact member to the upstream side in the sheet conveying direction. When the first contact member is provided from the other contact member to the upstream side in the sheet conveyance direction, the sheet is in contact with the portion of the first contact member located on the upstream side in the sheet conveyance direction from the other contact member. In order to prevent the sheet from being wrinkled or bent, it is preferable to rotate the upstream portion of the first contact member in the sheet conveying direction and move it to the opposite side of the loop.

  Further, when the first contact member is movably provided on the side opposite to the loop as described above, when the first contact member is urged to the loop side from the urging member, the loop is reduced. After the first contact member is appropriately moved to the opposite side of the loop by the contact of the sheet, the sheet is appropriately conveyed along each contact member, and after the sheet has passed through the first contact member, The first contact member is appropriately returned to the original state.

  In the image forming apparatus of the present invention, the sheet conveying apparatus as described above is used to convey a sheet of recording paper or the like stored in a paper feeding cassette.

  In the image reading apparatus according to the present invention, the sheet conveying apparatus as described above is used to convey a sheet made of a document set on a document table or the like.

  In the sheet conveying apparatus of the present invention, in the sheet conveying path between the first roller pair and the second roller pair, the sheet whose loop is reduced first comes into contact with the first contact member, and this sheet causes When one contact member moves to the opposite side of the loop, the sheet comes into contact with other contact members in stages, and the sound generated when the loop in the sheet is eliminated is reduced. Further, since the rotation control for the registration roller or the like is not performed as in the prior art, the roller rotation mechanism is not complicated, the sheet conveyance efficiency is lowered, and the image forming speed is also lowered. Absent.

  In addition, the sheet whose loop is being reduced first contacts the first contact member, the first contact member moves to the opposite side of the loop, and the sheet is further conveyed in contact with another contact member. As a result, the sheet is appropriately conveyed without being disturbed in the posture of the conveyed sheet, and it is also possible to prevent the sheet from being wrinkled or bent.

It is a figure which shows a prior art, Comprising: It is the graph which showed the change of the circumferential speed in a paper feed roller and a conveyance roller pair, and the change of the quantity of the loop formed in a sheet | seat. 1 is a mechanism configuration diagram of an image forming apparatus using a sheet conveying device according to an embodiment of the present invention. FIG. 3 is a mechanism configuration diagram illustrating an enlarged portion where a sheet feeding roller, a separation roller, a conveying roller pair, and a contact member are arranged in the sheet conveying device in the image forming apparatus illustrated in FIG. 2. FIG. 4 is a schematic perspective view illustrating a state in which first to third contact members are provided on an inner guide plate portion in the sheet conveying apparatus illustrated in FIG. 3. FIG. 4 is a schematic cross-sectional explanatory view showing a state in which the first and second contact members are movably provided on the inner guide plate portion on the side opposite to the loop in the sheet conveying apparatus shown in FIG. 3. FIG. 4 is a schematic cross-sectional explanatory diagram illustrating a process in which a sheet is sequentially brought into contact with first to third contact members by reducing a loop in the sheet in the sheet conveying apparatus illustrated in FIG. 3. FIG. 5 is a schematic cross-sectional explanatory view showing a modified example in the case where the first and second contact members are movably provided on the inner guide plate portion on the side opposite to the loop in the sheet conveying device in the image forming apparatus shown in FIG. 2. is there. FIG. 5 is a schematic perspective view illustrating a modification example in the case where first to third contact members are provided in a portion of an inner guide plate in the sheet conveying device in the image forming apparatus illustrated in FIG. 2. It is a mechanism block diagram showing an image reading apparatus having a sheet conveying apparatus according to an embodiment of the present invention.

  Next, a sheet conveying apparatus according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings. Note that the sheet conveying apparatus according to the present invention is not limited to the one shown in the following embodiment, and can be implemented with appropriate modifications within a range not changing the gist thereof.

  FIG. 2 shows an image forming apparatus provided with the sheet conveying apparatus of this embodiment. The image forming apparatus is, for example, a printer that forms an image on a sheet based on image data or text data input from the outside via a network or the like. A path 20, an image forming unit 30, a fixing unit 40, a paper discharge unit 50, and the like are provided.

  The paper feeding unit 10 includes a paper feeding tray 11, a pickup roller 12, a paper feeding roller 13, a separation roller 14, and the like. When the pickup roller 12 rotates, the uppermost sheet stacked on the sheet feeding cassette 11 is fed between a pair of rollers including a sheet feeding roller 13 and a separation roller 14.

  A torque limiter (not shown) is provided on the rotation shaft of the separation roller 14. The rotation limit force of the torque limiter is set to be larger than the friction force between the sheets, and is set to be smaller than the friction force between the sheet and the separation roller 14.

  Therefore, when a single sheet is fed between the paper feed roller 13 and the separation roller 14, the frictional force between the single sheet and the separation roller 14 is the rotation limiting force of the torque limiter. The separation roller 14 also rotates and conveys the single sheet. On the other hand, when two or more sheets are fed between the paper feed roller 13 and the separation roller 14, the friction force between the sheets is below the rotation limit force of the torque limiter, so the separation roller does not rotate. Only the sheet in contact with the paper feed roller 13 is conveyed by the paper feed roller 13.

  The sheet conveyance path 20 includes an image forming path 20A, a paper discharge / reverse path 20B, a double-side conveyance path 20C, and various rollers disposed on these paths. The image forming path 20A is provided with a conveying roller pair 21, a registration roller pair 22, a secondary transfer roller 34, a fixing unit 40, and the like, and the sheet taken out by the paper feeding roller 13 is located downstream thereof. After passing through the conveying roller pair 21, the image forming apparatus waits at a position of the registration roller pair 22 and is conveyed by the registration roller pair 22 in accordance with the timing of image formation.

  A paper discharge roller 23A and a reverse roller 23B are provided in the paper discharge / reverse path 20B. In the case of single-sided printing, the sheet that has passed through the image forming path 20A is guided to the paper discharge / reverse path 20B, and is discharged as the paper discharge roller 23A rotates in the forward direction. On the other hand, in the case of duplex printing, the single-side printed sheet that has passed through the image forming path 20A is guided to the reverse roller 23B side by the switching claw 24, and the reverse roller 23B rotates in the forward direction and then in the reverse direction. By doing so, the sheet end which was the rear end becomes the leading end and is guided to the duplex conveyance path 20C.

  The image forming unit 30 includes an image forming unit 30Y for yellow, an image forming unit 30M for magenta, an image forming unit 30C for cyan, an image forming unit 30K for black, and an intermediate transfer belt 33. And a secondary transfer roller 34. For example, the image forming unit 30Y includes a photosensitive drum 31, a charging device (not shown) arranged around the photosensitive drum 31, an exposure device, a developing device, a primary transfer roller, and a cleaning device. The other color image forming units 30M, 30C, and 30K have the same configuration as the image forming unit 30Y.

  The toner images formed on the respective photosensitive drums 31 of the image forming units 30Y, 30M, 30C, and 30K of the respective colors are primarily transferred onto the intermediate transfer belt 33 in order, and the full color is formed on the intermediate transfer belt 33. A toner image is formed. When the sheet passes between the intermediate transfer belt 33 and the secondary transfer roller 34, the toner image on the intermediate transfer belt 33 is transferred to one surface of the sheet.

  The fixing unit 40 includes, for example, a heat fixing roller 41 having a heat source and a pressure roller 42 in contact with the heat fixing roller 41, and heats and heats a sheet on which a toner image passing between both the rollers 41 and 42 is formed. The toner image transferred to the sheet is pressed and fixed on the sheet. The sheets subjected to the fixing process are stacked on the paper discharge unit 50.

  Here, in this embodiment, as shown in FIGS. 3 and 4, the portion from the sheet feeding roller 13 to the conveyance roller pair 21 in the sheet conveyance path 20 has a curved shape for guiding the sheet S. The inner guide plate 15 and the outer guide plate 16 are arranged with a required interval therebetween. A plurality of contact members 17 are provided along the conveying direction of the sheet S so as to protrude from the inner guide plate 15 toward the loop formed by the sheet S.

  Here, as the contact member 17, a first contact member 17 a that protrudes largest on the loop side is provided at the center in the width direction of the inner guide plate 15 that intersects the conveyance direction of the sheet S. On both sides of the contact member 17a, two second contact members 17b having a length that protrudes toward the loop side from the first contact member 17a are provided, and the inner guide plates 15 are further provided from the respective second contact members 17b. Two third contact members 17c having a length that protrudes toward the loop side from the second contact member 17b are provided on the outer side in the width direction.

  Further, in the first contact member 17a and the second contact member 17b protruding from the third contact member 17c to the loop side, as shown in FIG. While being held by the plate 15, the first contact member 17 a and the second contact member 17 b are urged in a direction in which the first contact member 17 a and the second contact member 17 b protrude toward the loop side by the urging members 19 made of springs held by the fixing members 18. . On the other hand, the third contact member 17c is attached to the inner guide plate 15 so as to protrude to the loop side, and does not move to the opposite side of the loop. The third contact member 17c can be attached to the fixing member 18 so as to protrude from the inner guide plate 15 to the loop side.

  Next, the leading edge of the sheet S is guided to the conveyance roller pair 17, and a loop is formed on the sheet S in a portion from the sheet feeding roller 13 to the conveyance roller pair 21 in the sheet conveyance path 20. The state in which the rotation is stopped, the loop formed in the sheet S is reduced, and the sheet S is in contact with the first to third contact members 17a to 17c is based on FIGS. 6 (A) to (C). explain.

  When the loop in the sheet S starts to decrease, first, as shown in FIG. 6A, the sheet S comes into contact with the first contact member 17a that protrudes the largest on the loop side at the center in the width direction of the inner guide plate 15. To do. When the loop in the sheet S further decreases, the sheet S pushes the first contact member 17a to the opposite side of the loop, and resists the biasing member 19 as shown in FIG. 6B. The first contact member 17a moves to the opposite side of the loop, and the sheet S comes into contact with the second contact members 17b provided on both sides of the first contact member 17a. Further, when the loop in the sheet S is reduced, the first contact member 17a and the second contact member 17b are pushed to the opposite side of the loop by the sheet S, and as shown in FIG. The first contact member 17 a and the second contact member 17 b move to the opposite side of the loop against the urging member 19, and the sheet S is provided on the both sides in the width direction of the inner guide plate 15. It contacts the contact member 17c.

  The sheet S is conveyed by the conveying roller pair 21 in a state where the sheet S is in contact with the first to third contact members 17a to 17c, and the rear end of the sheet S is the first to third contact members. After passing through the portion provided with 17a to 17c, the first contact member 17a and the second contact member 17b are returned to their original positions by the biasing member 19.

  In this way, after the sheet S whose loop is being reduced comes into contact with the first contact member 17a, the first contact member 17a is pushed by the sheet S and moves to the opposite side of the loop. S contacts the second contact member 17b, and the first contact member 17a and the second contact member 17b are pushed by the sheet S and move to the opposite side of the loop to contact the third contact member 17c. As a result, the sound generated when the loop of the sheet S is eliminated is reduced.

  Further, after the sheet S comes into contact with the first contact member 17a in the center portion in the width direction of the inner guide plate 15, the third contact with the second contact member 17b provided on both sides of the first contact member 17a. The first contact member 17a and the second contact member 17b are pushed to the opposite side of the loop, and the first to third contact members 17a to 17c have the same height. In this state, the sheet S is conveyed in contact with the first to third contact members 17a to 17c, so that the sheet S is appropriately conveyed without disturbing the posture of the conveyed sheet S. As a result, the sheet S is also prevented from being wrinkled or broken.

  As shown in FIG. 7, the first contact member 17a and the second contact member 17b are placed in the holding portions 15a provided so as to protrude from the inner guide plate 15 to the loop side of the sheet S. Each of the first contact member 17a and the second contact member 17b is attached in a direction to protrude to the loop side by each biasing member 19 provided in each holding portion 15a. It can also be used.

  Even in this case, when the loop in the sheet S is reduced, the sheet S comes into contact with the first contact member 17a, and then the first contact member 17a is pushed by the sheet S and loops. The sheet S comes into contact with the second contact member 17b, and the first contact member 17a and the second contact member 17b are pushed by the sheet S and move to the opposite side of the loop. S comes into contact with the third contact member 17c, the sound generated when the loop of the sheet S is eliminated, and the posture of the conveyed sheet S is appropriately conveyed without being disturbed. As a result, the sheet S is also prevented from being wrinkled or broken.

  Further, in the one shown in FIG. 8, the first to third contact members 17a to 17c have substantially the same height protruding to the loop side of the sheet S, while the first to third contact members 17a. When the ˜17c is provided along the conveyance direction of the sheet S, the lengths extending to the upstream side in the conveyance direction of the sheet S are made different in the first to third contact members 17a to 17c. The length extending to the upstream side in the conveyance direction of the sheet S is set so that the first contact member 17a at the center in the width direction of the inner guide plate 15, the second contact members 17b on both sides of the first contact member 17a, The first contact member 17a is longest in the order of the third contact member 17c on the outer side in the width direction of the inner guide plate 15 from the second contact member 17b.

  Further, in the first contact member 17a and the second contact member 17b described above, the portion on the upstream side in the transport direction is rotated around the downstream portion in the transport direction of the sheet S and moved to the opposite side of the loop. In addition, the first contact member 17a and the second contact member 17b that are rotated in this manner are attached to the upstream side of the sheet S in the conveying direction by the urging member 19 in a direction protruding toward the loop side. I'm energizing.

  When the first to third contact members 17a to 17c are provided in this way, when the loop in the sheet S starts to decrease, the sheet S is first upstream in the conveyance direction of the sheet S in the first contact member 17a. The portion of the first contact member 17a on the upstream side in the conveyance direction of the sheet S rotates against the biasing member 19 to the opposite side of the loop, and is pressed by the sheet S. Comes into contact with the upstream portion of the second contact member 17b provided on both sides of the first contact member 17a in the conveyance direction of the sheet S. Further, when the loop in the sheet S is reduced, the sheet S is pushed by the sheet S, and the portion of the first contact member 17a and the second contact member 17b on the upstream side in the transport direction of the sheet S becomes the urging member 19. Accordingly, the sheet S rotates to the opposite side of the loop, and the sheet S comes into contact with the third contact members 17 c provided on both sides of the inner guide plate 15 in the width direction.

  The sheet S is conveyed by the conveying roller pair 21 in a state where the sheet S is in contact with the first to third contact members 17a to 17c, and the rear end of the sheet S is the first to third contact members. When passing through the portion provided with 17a to 17c, the upstream portion in the transport direction of the sheet S in the first contact member 17a and the second contact member 17b that has been rotated to the opposite side of the loop is an urging member. It is urged by 19 to return to the original position.

  For this reason, also in this case, as in the case described above, the sound generated when the loop of the sheet S is canceled is reduced, and the posture of the conveyed sheet S is appropriately not disturbed. Therefore, the sheet S is also prevented from being wrinkled or broken.

  In the above description, the example in which the sheet conveying device is used for the paper feeding unit 10 in the image forming apparatus has been described. However, the sheet conveying device can also be used for the image reading device.

  FIG. 9 shows a sheet conveying apparatus of the image reading apparatus 100. In this sheet conveying apparatus, when the pickup roller 101 rotates, the uppermost sheet (original) S on the original table is sent between the paper supply roller 102 and the separation roller 103. A torque limiter (not shown) is provided on the rotation shaft of the separation roller 103. Even if two or more sheets S are fed between the paper feed roller 102 and the separation roller 103 by this torque limiter, the frictional force between the sheets is less than the rotation limit force of the torque limiter. Only the sheet that does not rotate and is in contact with the paper feed roller 102 is conveyed by the paper feed roller 102.

  In addition, a lower guide plate 106 and an upper guide plate 107 that guide the sheet S are arranged at a required interval in a sheet conveyance path 105 that guides the sheet S conveyed by the sheet feeding roller 102 to the conveyance roller pair 104. Yes.

  Then, the first to third contact members 17a to 17c are moved along the conveying direction of the sheet S so as to protrude from the lower guide plate 106 toward the loop formed by the sheet S. Provided.

  That is, in the sheet conveying device of the image reading apparatus 100, the first contact member 17a that protrudes the largest on the loop side at the center in the width direction of the lower guide plate 106, and on both sides of the first contact member 17a. Two second contact members 17b having a length that protrudes to the loop side from the first contact member 17a are smaller, and the second guide member 17b has a second outer side in the width direction of the lower guide plate 106 than the second contact member 17b. Two third contact members 17c having a length that protrudes toward the loop side from the contact member 17b are reduced. As in the case described above, the first contact member 17a and the second contact member 17b are held by the lower guide plate 106 so as to be movable to the opposite side of the loop, and the first contact member 17a. And the 2nd contact member 17b is urged | biased in the direction which protrudes in the loop side by the urging | biasing member 19 which consists of a spring each hold | maintained at the fixing member 18.

  A registration roller pair 108 is provided on the downstream side of the conveying roller pair 104, and a document reading optical unit (not shown) is provided on the downstream side of the registration roller pair 108.

  Also in the document reading apparatus 100, when the first to third contact members 17a to 17c are provided as described above, a loop of the sheet S is formed as in the case of the sheet feeding unit 10 in the image forming apparatus. When the sheet S is canceled, the sheet S comes into contact with the first to third contact members 17a to 17c in order, and a sound generated when the loop is canceled is reduced, and the posture of the conveyed sheet S is changed. The sheet S is appropriately conveyed without being disturbed, and the sheet S is also prevented from being wrinkled or broken.

DESCRIPTION OF SYMBOLS 1 Apparatus main body 10 Paper feed part 12 Pickup roller 13 Paper feed roller 14 Separation roller 15 Inner guide plate 15a Holding part 16 Outer guide plate 17 Contact member 17a First contact member 17b Second contact member 17c Third contact member 18 Fixing member 19 Energizing member 20 Sheet conveying path 21 Conveying roller pair 22 Registration roller pair 30 Image forming unit 40 Fixing unit 50 Discharge unit 100 Image reading device 102 Paper feeding roller 103 Separating roller 104 Conveying roller pair 105 Sheet conveying path 106 Below Guide plate 107 Upper guide plate 108 Registration roller pair S sheet

Claims (9)

  A first roller pair having a roller to which a rotation limiting force of a torque limiter is applied, a second roller pair disposed downstream of the first roller pair in the sheet conveying direction, and the first roller pair. Two or more contact members projecting toward the loop formed by the sheet in the sheet conveyance path between the second roller pair and having different timings to contact the sheet that reduces the loop are provided, and at least the loop is reduced. A sheet conveying apparatus, wherein a first contact member that first comes into contact with a sheet to be moved is provided so as to be movable on the side opposite to the loop.   The sheet conveying apparatus according to claim 1, wherein each of the contact members is provided along a sheet conveying direction.   3. The sheet conveying apparatus according to claim 1, wherein the first contact member is provided at a central portion in a direction intersecting a sheet conveying direction. 4.   4. The sheet conveying apparatus according to claim 1, wherein the first contact member is provided so as to protrude toward a loop formed by the sheet from another contact member. 5. Sheet conveying device.   The sheet conveying apparatus according to any one of claims 1 to 3, wherein the first contact member is provided from the other contact member to the upstream side in the sheet conveying direction. Conveying device.   6. The sheet conveying apparatus according to claim 5, wherein a portion of the first contact member on the upstream side in the sheet conveying direction is rotatably provided, and a portion of the first contact member on the upstream side in the sheet conveying direction is provided. A sheet conveying apparatus that is rotated and moves to the opposite side of the loop.   7. The sheet conveying apparatus according to claim 1, wherein at least the first contact member is biased toward the loop side formed by the sheet from the biasing member, and is opposite to the loop. The sheet conveying apparatus is provided so as to be movable.   An image forming apparatus comprising the sheet conveying device according to claim 1.   An image reading apparatus comprising the sheet conveying device according to claim 1.

Images