JP4260762B2 - Document feeder and image forming apparatus - Google Patents

Description

  The present invention relates to an original feeding apparatus and an image forming apparatus that use a sheet through system.

  As a document feeder provided in a conventional image forming apparatus, there is known a document feeder provided with a regulating plate for preventing the deviation of the conveying belt (for example, see Patent Document 1). In addition, a conveying belt is known in which a ridge continuously extending in the document feeding direction is provided on the inner surface, and the ridge provided on the inner surface can be used as a guide for preventing meandering (for example, patents). Reference 2).

  In the conventional document feeder, in the case where a regulating plate for preventing the deviation of the conveying belt is provided, the end of the operating conveying belt is suppressed by the stationary regulating plate. There is a problem that it is easy to occur.

  In addition, in the case of a belt provided with a conveyor belt provided on the inner surface with ridges continuously extending in the document feeding direction, the ridges provided on the inner surface of the conveyor belt continuously extend in the document feeding direction. As a result, the convex portion of the conveying belt hung on the roller rises and the flatness of the outer peripheral surface of the conveying belt is impaired, and as a result, the conveying force of the document depends on the location on the conveying belt. There was a problem that a difference was caused to cause a conveyance failure such as skew.

  In order to eliminate such a problem, in order to prevent a lateral deviation of the conveyance belt arranged in the image forming apparatus in a direction perpendicular to the belt conveyance direction, the conveyance belt is fixed to the conveyance belt side and a plurality of conveyance rollers are arranged. There is a gear-shaped guide member arranged in contact with the end face, and this guide member is engaged with a timing pulley formed on each of a plurality of conveying rollers (see, for example, Patent Document 3).

Japanese Patent Laid-Open No. 7-315614 (page 3, FIG. 2) JP-A-5-139564 (page 3, FIG. 1) JP 2003-95472 A

  However, in such a conventional document feeder, the tooth-shaped guide member is engaged with the timing pulleys of the plurality of conveying rollers, but is formed over the circumferential direction of the plurality of conveying rollers. Since the width of the groove of the timing pulley is the same, it is necessary to attach the conveyor belt to the conveyor roller so that the grooves of the plurality of conveyor rollers are aligned on the same line, and high mounting accuracy is required.

  In addition, when the conveyance belt is attached to the conveyance roller so that the grooves of the plurality of conveyance rollers do not coincide on the same line, the rotation of the conveyance roller occurs when the guide member is engaged with the groove of the timing belt. The guide member slips out of the groove, causing a problem that the lateral deviation of the conveying belt occurs and the original cannot be stably conveyed, and there is still room for improvement.

  The present invention has been made to solve the conventional problems, and can eliminate the need to attach the document feeding belt to the belt roller with high accuracy, and the convex portion of the document feeding belt can be used for the belt roller. It is an object of the present invention to provide a document feeding device and an image forming apparatus that can prevent a slippage from coming out of a recess and stably feed a document.

The document feeding device of the present invention includes a document feeding belt for feeding a document, and a plurality of documents fed on the document feeding belt such that a direction substantially orthogonal to the feeding direction of the document by the document feeding belt is an axial direction. A belt roller, and the document feeding belt includes a convex row portion in which a plurality of convex portions are intermittently arranged in the document feeding direction, and the belt roller is provided on an outer peripheral surface to provide the convex roller. A concave portion into which the convex portion is inserted, the width of the concave portion being different from at least one of the plurality of belt rollers, and the arrangement interval of the convex portions being non-uniform. Has been.

  With this configuration, since the width of the concave portion of at least one belt roller of the plurality of belt rollers is different from the width of the concave portion of the other belt roller, when the convex portion is inserted into the wide concave portion, A gap can be provided between the concave portion and the convex portion.

  For this reason, when the belt feeding roller and the document feeding belt are assembled, when the document feeding belt is attached to the belt roller so that the projections of the document feeding belt are inserted into the recesses of the plurality of belt rollers, It is unnecessary to attach the document feeding belt with high accuracy.

In addition, when the document feeding belt is attached to the belt roller and the document is transported, the convex portion of the document feeding belt can be prevented from coming off from the concave portion of the belt roller, thereby stabilizing the document. Can be sent.
Also, if the convex spacing is uniform, when the original feeding belt is moved, the resonance frequency of the original feeding belt becomes constant and noise is generated, but the convex spacing is uneven. Thus, when the document feeding belt is moved, it is possible to prevent noise from being generated without making the resonance frequency of the document feeding belt constant.

  Further, the document feeder of the present invention is configured such that the width of the concave portion of the belt roller located on the most upstream side in the document feeding direction is narrower than the width of the concave portion of the other belt roller.

  With this configuration, since the convex portion of the document feeding belt is strongly inserted into the concave portion of the belt roller located on the most upstream side in the document feeding direction, it is possible to prevent lateral displacement of the document feeding belt in this portion. Can do. For this reason, the leading edge of the document can smoothly enter the document feeding belt, and the document skew can be prevented from occurring.

Further, the document feeder of the present invention is configured by the width of the concave portion of the belt roller located on the most downstream side in the document feeding direction being narrower than the width of the concave portion of the other belt roller.
With this configuration, since the convex portion of the document feeding belt is strongly inserted into the concave portion of the belt roller located on the most downstream side in the document feeding direction, it is possible to prevent lateral displacement of the document feeding belt in this portion. Can do. For this reason, since it can be pulled to the downstream side of the document feeding belt, it is possible to prevent the document from being largely displaced laterally.

  In addition, the document feeder of the present invention is configured such that, among the plurality of belt rollers, the width of the concave portion of the belt roller constituting the driving roller is narrower than the width of the concave portion of the other belt roller. ing.

  With this configuration, since the convex portion of the document feeding belt is strongly inserted into the concave portion of the driving roller, it is possible to prevent the lateral displacement of the document feeding belt at this portion. For this reason, it is possible to increase the document conveying force.

  The document feeder according to the present invention is configured such that, among the plurality of belt rollers, the width of the concave portion of the belt roller constituting the driven roller is narrower than the width of the concave portion of the other belt roller. ing.

  With this configuration, since the convex portion of the document feeding belt is strongly inserted into the concave portion of the driven roller having a smaller driving force than the driving roller, it is possible to prevent the lateral displacement of the document feeding belt in this portion. For this reason, the document can be stably conveyed.

In the document feeder according to the present invention, the projection has a configuration in which a portion that is narrowed from the base side toward the tip side is provided.
With this configuration, the document feeding device according to the present invention can suppress the abrasion of the projection of the document feeding belt due to friction with the concave portion of the belt roller, and therefore cannot suppress the abrasion of the projection of the document feeding belt. Compared with the configuration, it is possible to extend the period during which the deviation of the document feeding belt can be prevented.

  In the document feeding device of the present invention, the document feeding belt has a configuration in which the projection row portion is provided at a portion other than an end portion in a direction substantially orthogonal to the document feeding direction.

  With this configuration, the document feeding device according to the present invention has a lower rigidity than the other parts and the document feeding belt does not have a protruding row portion at the end that is easily deformed. Can be prevented from coming out, and the original can be fed more stably.

  In the document feeding device according to the present invention, the document feeding belt includes a plurality of the protrusion row portions, and the belt roller includes a plurality of the concave portions corresponding to the plurality of the protrusion row portions. Have.

  With this configuration, the document feeding device according to the present invention prevents the document feeding belt from being displaced by the plurality of protrusion rows of the document feeding belt, so that the belt roller and the document feeding belt can be more reliably synchronized. Therefore, the document feeding device of the present invention can prevent twisting of the document feeding belt that impairs the flatness of the outer peripheral surface of the document feeding belt, and can feed the document more stably.

In the document feeder of the present invention, at least one of the plurality of concave portions of the belt roller is configured to be provided in the belt roller so as to be movable in the axial direction.
With this configuration, the document feeding device according to the present invention allows the projection of the document feeding belt to be a concave portion of the belt roller even when it is difficult to strictly limit the dimensional tolerance of the document feeding belt from the viewpoint of the manufacturing method. Therefore, the flatness of the outer peripheral surface of the document feeding belt can be ensured, and the document can be fed more stably.

  The image forming apparatus of the present invention includes the above-described document feeder.

  With this configuration, since the width of the concave portion of at least one belt roller of the plurality of belt rollers is different from the width of the concave portion of the other belt roller, when the convex portion is inserted into the wide concave portion A gap can be provided between the concave portion and the convex portion.

  For this reason, when the belt feeding roller and the document feeding belt are assembled, when the document feeding belt is attached to the belt roller so that the projections of the document feeding belt are inserted into the recesses of the plurality of belt rollers, It is unnecessary to attach the document feeding belt with high accuracy.

  In addition, when the document feeding belt is attached to the belt roller and the document is transported, the convex portion of the document feeding belt can be prevented from coming off from the concave portion of the belt roller, thereby stabilizing the document. Can be sent.

  The present invention eliminates the need to attach the document feeding belt to the belt roller with high accuracy, and prevents the projection of the document feeding belt from coming off from the recess of the belt roller. Thus, it is possible to provide a document feeder and an image forming apparatus that can feed a document.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
First, FIG. 1 to FIG. 6 explain the configuration of an automatic document feeder as a document feeder according to the first embodiment and an image forming apparatus provided with the automatic document feeder.

  As shown in FIG. 1, a color image forming apparatus 200 such as a copying machine, a printer, or a facsimile machine is provided around an image carrier 201 (201Y (yellow), 201M (magenta), 201C (cyan), 201B (black)). Further, an exposure device 211, a charging device 221, a developing device 222, a transfer device 223, a cleaning device 224, and a fixing device 225 are provided.

  For the image carrier 201, an amorphous metal having photoconductivity, an amorphous metal such as amorphous selenium, or an organic compound such as a bisazo pigment or a phthalocyanine pigment can be used. Considering the environment and post-treatment after use, it is preferable to use an organic compound.

  The charging device 221 may be any one of a corona method, a roller method, a brush method, and a blade method. Here, the charging device 221 of a roller method is shown. The charging device 221 applies a predetermined voltage to the image carrier 201 and generates a corona discharge with the image carrier 201 to uniformly charge the surface of the image carrier 201.

  The exposure device 211 converts data read by the scanner in the reading device 210 and an image signal sent from the outside such as a PC (not shown), scans the laser beam with a polygon motor, and based on the image signal read through the mirror. An electrostatic latent image is formed on the carrier 201.

  The developing device 222 includes a developer carrier that supports the developer and supplies the developer to the image carrier 201, a toner supply chamber, and the like, and magnetically attracts the developer to the outer peripheral surface of the developer carrier. It is designed to be transported. The developer carrying member is made of a non-magnetic member that is electrically conductive, and is connected to a power source for applying a developing bias. A voltage is applied from the power source between the developer carrier and the image carrier 201 to form an electric field in the development area.

The transfer device 223 includes a transfer belt, and an image formed on the image carrier 201 is transferred to the transfer belt.
The fixing device 225 includes a fixing roller having a heater that is a heating unit such as a halogen lamp, and a pressure roller that is in pressure contact.
The cleaning device 224 is configured to remove residual toner adhering to the image carrier 201 from the image carrier 201.

  In addition, paper feed cassettes 231a, 231b, 231c, and 231d in which recording paper is stored are provided below the image forming apparatus 200. The paper is fed by the paper feeding / conveying rollers 232a, 232b, 232c, and 232d, and then conveyed to the transfer device 223.

  The recording paper conveyed to the transfer device 223 is transferred to the fixing device 225 by the intermediate belt 234 after the image is transferred by the transfer device 223, and is discharged onto the paper discharge tray 235 after the image is fixed by the fixing device 225. Paper.

  On the other hand, the automatic document feeder 10 is mounted on the upper part of the main body 220 of the image forming apparatus 200 as shown in FIG. This automatic document feeder 10 includes a document table 11, a pickup roller 12, a paper feed belt 13, a reverse roller 14, a pull-out roller 15, a turn roller 16, a reading inlet roller 17, a reading outlet roller 18, a paper discharging roller 19, and paper discharging. A tray 20, a conveyance belt 30, a conveyance belt driving roller 40, a conveyance belt pressure roller 50, and a conveyance belt driven roller 60 are provided. A conveyance path is formed between each table, each belt, and each roller of the automatic document feeder 10 so that the document can be conveyed.

  The image forming apparatus 90 includes a reading unit 91 that is a reading position by the reading device 210, a slit glass 92, a document scale 93, and a platen glass 94 on the upper surface.

  As shown in FIG. 3, the conveying belt 30 is an endless belt formed of a thin cylindrical elastic material, and constitutes a document feeding belt for feeding a document. The conveyor belt 30 includes a protrusion row (convex portion row) 32 in which a plurality of protrusions (convex portions) 31 are intermittently arranged in the document feeding direction indicated by an arrow 30a on the inner peripheral surface.

  As shown in FIG. 4, the transport belt driving roller 40, the transport belt pressure roller 50, and the transport belt driven roller 60 include a recess 41, a recess 51, and a recess 61 on the outer peripheral surface, respectively. Further, as shown in FIGS. 5 and 6, the transport belt driving roller 40, the transport belt pressure roller 50, and the transport belt driven roller 60 are transported so that the direction substantially perpendicular to the direction indicated by the arrow 30a is the axial direction. A belt 30 is hung and constitutes a belt roller.

The protrusion 31 of the conveyor belt 30 is inserted and fitted into the recess 41 of the conveyor belt drive roller 40, the recess 51 of the conveyor belt pressure roller 50, and the recess 61 of the conveyor belt driven roller 60, respectively.
Further, the width of the recess 61 of the transport belt driven roller 60 is narrower than the width of the recess 41 and the recess 51, and the protrusion 31 is inserted into the recess 61 with the strongest force.

Next, the operation of the automatic document feeder 10 will be described.
As shown in FIG. 2, the topmost document in the document bundle 99 set on the document table 11 is separated from the document bundle 99 by the pickup roller 12, the paper feed belt 13, and the reverse roller 14, and the pull-out roller 15. Then, it is conveyed by the turn roller 16 and the reading entrance roller 17 and reaches the reading unit 91 of the image forming apparatus 90. The document that has reached the reading unit 91 is read by the reading unit 91 of the image forming apparatus 90 while being conveyed on the slit glass 92 by the conveying belt 30 driven by the conveying belt driving roller 40, and then the reading exit roller 18. Then, the paper is conveyed by the paper discharge roller 19 and discharged onto the paper discharge tray 20 to be stacked.

  The conveyor belt pressure roller 50 and the conveyor belt driven roller 60 rotate in synchronization with the conveyor belt 30 when the conveyor belt 30 is driven by the conveyor belt drive roller 40.

  Further, as shown in FIGS. 5 and 6, the protrusion 31 of the conveyor belt 30 is configured such that when the conveyor belt 30 is driven by the conveyor belt drive roller 40, the recess 41 of the conveyor belt drive roller 40, the conveyor belt pressure roller 50. The recess 51 and the recess 61 of the conveyor belt driven roller 60 enter and exit one after another.

  Therefore, the conveyance belt 30 has a direction indicated by an arrow 30a by engagement of the protrusion 31 with the concave portion 41 of the conveyance belt driving roller 40, the concave portion 51 of the conveyance belt pressure roller 50, and the concave portion 61 of the conveyance belt driven roller 60. A shift in a substantially orthogonal direction is prevented.

  In particular, in the present embodiment, the width of the recess 61 of the transport belt driven roller 60 is made narrower than the width of the recess 41 of the transport belt driving roller 40 and the recess 51 of the transport belt pressure roller 50, so that the protrusion 31 is wide. When inserted into the recesses 41 and 51, a gap can be provided between the recesses 41 and 51 and the protrusion 31.

  Therefore, when the rollers 40, 50, 60 and the conveyor belt 30 are assembled, the rollers 40, 50 are configured such that the protrusions 31 of the conveyor belt 30 are inserted into the recesses 41, 51, 61 of the rollers 40, 50, 60. , 60, it is not necessary to attach the conveyor belt 30 to each of the rollers 40, 50, 60 with high accuracy.

  In addition, when the conveyance belt 30 is attached to each of the rollers 40, 50, 60 and the document is conveyed, the protrusion 31 of the conveyance belt 30 is disengaged from the recesses 41, 51, 61 of each roller 40, 50, 60 And the document can be stably sent to the reading unit 91.

  In the present embodiment, the width of the recess 61 of the transport belt driven roller 60 located on the most downstream side is narrower than the width of the recesses 51 and 61 of the transport belt driving roller 40 and the transport belt pressure roller 50. The protrusion 31 of the conveyor belt 30 can be strongly inserted into the concave portion 61 of the conveyor belt driven roller 60, and the lateral deviation of the conveyor belt 30 at this portion can be prevented. Therefore, the leading edge of the document can smoothly enter the conveyance belt 30, and the document skew can be prevented from occurring. As a result, the document reading performance can be improved.

  In the present embodiment, the width of the recess 61 of the transport belt driven roller 60 is narrower than the width of the recesses 41 and 51 of the transport belt driving roller 40 and the transport belt pressure roller 50. In comparison, the protrusion 31 of the conveyor belt 30 can be strongly inserted into the recess 61 of the conveyor belt driven roller 60 having a smaller driving force. For this reason, it is possible to prevent the lateral displacement of the conveyance belt 30 in this portion, and it is possible to convey the document stably. As a result, the document reading performance can be improved.

  In this embodiment, the width of the concave portion 61 of the conveyance belt driven roller 60 located on the most downstream side is narrowed, but instead, the conveyance belt drive located on the most upstream side in the document feeding direction is used. The width of the recess 41 of the roller 40 may be narrower than the width of the recesses 51 and 61 of the transport belt pressure roller 50 and the transport belt drive roller 60.

  In this way, the protrusion 31 of the conveyance belt 30 can be strongly inserted into the concave portion 41 of the conveyance belt drive roller 40 located on the most upstream side in the document feeding direction. It can be prevented from occurring. Therefore, the leading edge of the document can smoothly enter the conveyance belt, and the document skew can be prevented from occurring. As a result, the document reading performance can be improved.

  Further, since the protrusion 31 of the conveyor belt 30 can be strongly inserted into the concave portion 41 of the conveyor belt driving roller 40, it is possible to prevent the lateral displacement of the conveyor belt 30 at this portion, and to reduce the document conveying force. Can be bigger.

  In the present embodiment, the arrangement intervals of the protrusions 31 are made uniform, but they may be made non-uniform. If the arrangement interval of the protrusions 31 is made uniform in this way, when the conveyance belt 31 is moved, the resonance frequency of the conveyance belt 31 may become constant and noise may be generated. If the frequency is made non-uniform, it is possible to prevent generation of noise without making the resonance frequency constant.

(Second Embodiment)
7 to 9 illustrate the configuration of an automatic document feeder as an original feeder according to the second embodiment and an image forming apparatus including the automatic document feeder. The configuration of the image forming apparatus is the same as that shown in FIG.

  The configuration of the automatic document feeder according to the present embodiment includes a conveying belt 30 (see FIG. 3), a conveying belt driving roller 40 (see FIG. 4), a conveying belt pressure roller 50 (see FIG. 4), and a conveying belt driven roller. 60 (see FIG. 4), the conveyance belt 130, the conveyance belt driving roller 140, the conveyance belt pressure roller 150, and the conveyance belt driven roller 160 shown in FIGS. 7 and 8 are replaced with the automatic document according to the first embodiment. The configuration is the same as that of the feeding device 10 (see FIG. 3).

  As shown in FIG. 7, the transport belt 130 is an endless belt formed of a thin cylindrical elastic material, and constitutes a document feed belt for feeding a document. The conveying belt 130 includes a protrusion row portion (convex portion row portion) 132 in which a plurality of protrusions (protrusion portions) 131 are intermittently arranged in the document feeding direction indicated by an arrow 130 a on the inner peripheral surface.

Here, an inclined surface 131 a is formed on the protrusion 131 of the conveyance belt 130. That is, the protrusion 131 has a wedge shape that becomes narrower from the root side toward the tip side.
As shown in FIG. 8, the conveyor belt driving roller 140, the conveyor belt pressure roller 150, and the conveyor belt driven roller 160 have a concave portion 141, a concave portion 151, and a concave portion 161 on the outer peripheral surface, respectively. In addition, an inclined surface 141a, an inclined surface 151a, and an inclined surface 161a are formed in the concave portion 141 of the conveying belt driving roller 140, the concave portion 151 of the conveying belt pressure roller 150, and the concave portion 161 of the conveying belt driven roller 160, respectively.

Similarly to the first embodiment, the transport belt driving roller 140, the transport belt pressure roller 150, and the transport belt driven roller 160 are transported so that the direction substantially orthogonal to the direction indicated by the arrow 130a is the axial direction. A belt 130 is hung and constitutes a belt roller. As shown in FIG. 9, a protrusion 131 of the conveyor belt 130 is inserted and fitted into the recess 141 of the conveyor belt drive roller 140. Similarly, the protrusion 131 of the conveyor belt 130 is inserted and fitted into the recess 151 of the conveyor belt pressure roller 150 and the recess 161 of the conveyor belt driven roller 160.
Further, the width of the recess 161 of the transport belt driven roller 160 is narrower than the width of the recess 141 and the recess 151 of the transport belt driving roller 140 and the transport belt pressure roller 150, and the protrusion 131 has the strongest force on the recess 161. Is inserted. The operation of the automatic document feeder according to the present embodiment is the same as that of the automatic document feeder 10 according to the first embodiment, and a description thereof will be omitted.

  As described above, the automatic document feeder according to the present embodiment includes the portion where the protrusion 131 of the conveyance belt 130 becomes narrower from the base side toward the front end side. Wear of the protrusion 131 of the conveyor belt 130 due to friction with the recess 141, the recess 151 of the conveyor belt pressure roller 150, and the recess 161 of the conveyor belt driven roller 160 can be suppressed. Therefore, in the automatic document feeder according to the present embodiment, the conveyance belt 130 in the direction substantially orthogonal to the direction indicated by the arrow 130a is compared with the configuration in which the abrasion of the protrusion 131 of the conveyance belt 130 cannot be suppressed. The period during which the shift can be prevented can be extended.

  In addition, since the automatic document feeder according to the present embodiment can suppress the wear of the protrusion 131 of the conveyance belt 130, the scraped powder of the protrusion 131 of the conveyance belt 130 is removed from the image forming apparatus 90 (see FIG. 3). Scattering and deposition on the slit glass 92 (see FIG. 3) can be prevented. Therefore, the automatic document feeder according to the present embodiment can prevent streaks from being generated due to dirt on the slit glass 92 when the image forming apparatus 90 reads an image.

  Further, the effect relating to the width of the recesses 141, 151, 161 and the effect relating to the relationship between the recesses 141, 151, 161 of the rollers 140, 150, 160 into which the protrusions 131 are inserted are the same as in the first embodiment.

(Third embodiment)
10 to 13 illustrate an automatic document feeder as a document feeder according to the third embodiment and a configuration of an image forming apparatus including the automatic document feeder. The configuration of the image forming apparatus is the same as that shown in FIG.

  The configuration of the automatic document feeder according to the present embodiment includes a conveying belt 30 (see FIG. 3), a conveying belt driving roller 40 (see FIG. 4), a conveying belt pressure roller 50 (see FIG. 4), and a conveying belt driven roller. 60 (see FIG. 4), the conveyor belt 230, the conveyor belt driving roller 240, the conveyor belt pressure roller 250, and the conveyor belt driven roller 260 shown in FIGS. 10 to 13 are automatically operated according to the first embodiment. The configuration is the same as that of the document feeder 10 (see FIG. 3).

  As shown in FIG. 10, the conveyance belt 230 is an endless belt formed of a thin cylindrical elastic material, and constitutes a document feeding belt for feeding a document. Conveying belt 230 includes a plurality of protrusion rows (convex portions) 232 in which a plurality of protrusions (convex portions) 231 are intermittently arranged in the document feeding direction indicated by arrow 230a, and a plurality of conveying belts 230 in the document feeding direction indicated by arrows 230a. The protrusions (convex parts) 233 are intermittently arranged on the inner peripheral surface. As shown in FIG. 11, the conveyor belt 230 has a protruding row portion 232 at a portion other than the end portion 235 in a direction substantially orthogonal to the direction indicated by the arrow 230 a, that is, at a portion away from the end portion 235 by a distance 235 a. The protrusion row portion 234 is provided at a portion other than the end portion 236 in a direction substantially orthogonal to the direction indicated by the arrow 230a, that is, at a portion spaced a distance 236a inward from the end portion 236.

  As shown in FIG. 12, the conveyance belt drive roller 240 includes a recess 241 and a recess 242 on the outer peripheral surface. The conveyor belt pressure roller 250 includes a recess 251 and a recess 252 on the outer peripheral surface. The conveyor belt driven roller 260 includes a recess 261 and a recess 262 on the outer peripheral surface.

Similarly to the first embodiment, the transport belt driving roller 240, the transport belt pressure roller 250, and the transport belt driven roller 260 are transported so that the direction substantially perpendicular to the direction indicated by the arrow 230a is the axial direction. A belt 230 is hung and constitutes a belt roller.
As shown in FIG. 13, the protrusions of the conveyor belt 230 are respectively formed in the recess 242 of the conveyor belt driving roller 240, the recess 252 of the conveyor belt pressure roller 250, and the recess 262 of the conveyor belt driven roller 260 (see FIG. 12). 233 is inserted and fitted.
Similarly, a protrusion 231 of the conveyor belt 230 is inserted and fitted into the recess 241 of the conveyor belt driving roller 240, the recess 251 of the conveyor belt pressure roller 250, and the recess 261 of the conveyor belt driven roller 260, respectively.
The operation of the automatic document feeder according to the present embodiment is the same as that of the automatic document feeder 10 according to the first embodiment, and a description thereof will be omitted.

  As described above, the automatic document feeder according to the present embodiment has the conveyance belt in the direction substantially orthogonal to the direction indicated by the arrow 230a by the plurality of projection row portions 232 and 234 of the conveyance belt 230. Therefore, the conveyance belt 230, the conveyance belt driving roller 240, the conveyance belt pressure roller 250, and the conveyance belt driven roller 260 can be synchronized more reliably. Therefore, the automatic document feeder according to the present embodiment can prevent twisting of the conveyor belt 230 that impairs the flatness of the outer peripheral surface of the conveyor belt 230, and can more stably feed the document. Note that the automatic document feeder according to the present embodiment includes the two protrusion row portions 232 and 234 of the conveyance belt 230, but may include three or more protrusion row portions.

  Further, in the automatic document feeder according to the present embodiment, the conveyance belt 230 does not include the protruding row portions 232 and 234 at the end portions 235 and 236 which have low rigidity and are easily deformed as compared with other portions. The protrusion 231 of the conveyor belt 230 comes out of the recess 241 of the belt drive roller 240, the recess 251 of the conveyor belt pressure roller 250, and the recess 261 of the conveyor belt driven roller 260, the recess 242 of the conveyor belt drive roller 240, and the conveyor belt added. It is possible to prevent the protrusion 233 of the conveying belt 230 from coming out of the concave portion 252 of the pressure roller 250 and the concave portion 262 of the conveying belt driven roller 260, and the document can be fed more stably.

(Fourth embodiment)
14 to 16 illustrate an automatic document feeder as a document feeder according to a fourth embodiment and a configuration of an image forming apparatus including the automatic document feeder. The configuration of the image forming apparatus is the same as that shown in FIG.

  The configuration of the automatic document feeder according to the present embodiment is replaced with a conveying belt driving roller 240 (see FIG. 12), a conveying belt pressure roller 250 (see FIG. 12), and a conveying belt driven roller 260 (see FIG. 12). 14 is the same as the configuration provided in the automatic document feeder according to the third embodiment with the conveying belt driving roller 340, the conveying belt pressure roller 350, and the conveying belt driven roller 360 shown in FIG.

  As shown in FIG. 15, the transport belt drive roller 340 is composed of a drive roller body 341 and a drive roller that is coaxially connected to the drive roller body 341 and supported by the drive roller body 341 so as to be movable in the axial direction indicated by an arrow 340a. A roller 342 for use. The drive roller body 341 includes a recess 341a on the outer peripheral surface. The drive roller roller 342 includes a recess 342a on the outer peripheral surface.

  Similarly, as shown in FIG. 14, the conveyance belt pressure roller 350 is a pressure roller main body 351 that is coaxial with the pressure roller main body 351 and is movable in the axial direction indicated by the arrow 350a. And a pressure roller roller 352 supported by the roller 351. The pressure roller main body 351 includes a recess (not shown) on the outer peripheral surface. The pressure roller roller 352 includes a recess 352a on the outer peripheral surface.

  Similarly, the conveyance belt driven roller 360 includes a driven roller main body 361, a driven roller roller 362 that is coaxial with the driven roller main body 361 and is movable in the axial direction indicated by an arrow 360 a and supported by the driven roller main body 361. It has. The driven roller main body 361 includes a recess (not shown) on the outer peripheral surface. The driven roller roller 362 includes a recess 362a on the outer peripheral surface.

  Similarly to the third embodiment, the conveyance belt driving roller 340, the conveyance belt pressure roller 350, and the conveyance belt driven roller 360 are conveyed so that the direction substantially orthogonal to the direction indicated by the arrow 230a is the axial direction. A belt 230 is hung and constitutes a belt roller. As shown in FIGS. 15A and 15B, for example, it is difficult to strictly limit the dimensional tolerance of the conveyor belt 230 from the viewpoint of the manufacturing method, and the distance 237 between the protrusion 231 and the protrusion 233 is difficult. Even if there is an error, the driving roller roller 342 can move in the axial direction indicated by the arrow 340a of the conveying belt driving roller 340, so that the concave portion 341a of the driving roller main body 341 of the conveying belt driving roller 340 is conveyed. The protrusions 231 and 233 of the conveyor belt 230 are securely inserted and fitted in the recesses 342a of the driving roller roller 342 of the belt driving roller 340, respectively.

  Similarly, since the pressure roller roller 352 can move in the axial direction indicated by the arrow 350a of the conveyance belt pressure roller 350, the concave portion of the pressure roller body 351 of the conveyance belt pressure roller 350, the conveyance belt pressure roller, and the like. The protrusions 231 and 233 of the conveyor belt 230 are securely inserted and fitted in the recesses 352a of the 350 pressure roller rollers 352, respectively.

  Similarly, since the driven roller roller 362 in the axial direction indicated by the arrow 360a of the transport belt driven roller 360 is movable, the recessed portion of the driven roller body 361 of the transport belt driven roller 360, the driven roller of the transport belt driven roller 360, and the like. In the recess 362a of the roller 362, the protrusion 231 and the protrusion 233 of the conveyor belt 230 are securely inserted and fitted, respectively.

  Note that the operation of the automatic document feeder according to the present embodiment is the same as the operation of the automatic document feeder 10 according to the third embodiment, and a description thereof will be omitted.

  As described above, the automatic document feeder according to the present embodiment, for example, even when it is difficult to strictly limit the dimensional tolerance of the conveyor belt 230 from the viewpoint of the manufacturing method, The protrusion 231 cannot be inserted into the recess 341 a of the transport belt driving roller 340, the recess of the pressure roller body 351 of the transport belt pressure roller 350, or the recess of the driven roller body 361 of the transport belt driven roller 360, or the transport belt 230. It is possible to prevent the protrusion 233 from being inserted into the recess 342 a of the transport belt driving roller 340, the recess 352 a of the transport belt pressure roller 350 or the recess 362 a of the transport belt driven roller 360. Can ensure the flatness of the document and send the document more stably It can be.

  As described above, the document feeding device and the image forming apparatus according to the present invention can eliminate the need for attaching the document feeding belt to the belt roller with high accuracy, and the convex portion of the document feeding belt is the belt roller. An image forming apparatus such as a document feeding apparatus and a copying machine, a printer, or a facsimile apparatus that uses a sheet-through method and has an effect of stably feeding a document while preventing the projection from coming off from the convex portion of the sheet. Useful as such.

1 is a side sectional view of an image forming apparatus according to a first embodiment of the present invention. Side surface sectional view of the automatic document feeder according to the first embodiment FIG. 2 is a perspective view of a part of the conveyance belt of the automatic document feeder shown in FIG. FIG. 2 is a perspective view of a part of a conveyance belt driving roller, a conveyance belt pressure roller, and a conveyance belt driven roller of the automatic document feeder shown in FIG. FIG. 2 is a perspective view of a part of the conveying belt, the conveying belt driving roller, and the conveying belt pressure roller of the automatic document feeder shown in FIG. FIG. 2 is a perspective view of a part of the conveyance belt, conveyance belt driving roller, conveyance belt pressure roller, and conveyance belt driven roller of the automatic document feeder shown in FIG. A perspective view of a part of a conveyor belt of an automatic document feeder according to a second embodiment of the present invention FIG. 6 is a perspective view of a part of a conveyance belt driving roller, a conveyance belt pressure roller, and a conveyance belt driven roller of an automatic document feeder according to a second embodiment of the present invention. 7 is a sectional view of a part of the conveyor belt shown in FIG. 7 and the conveyor belt drive roller shown in FIG. The perspective view of the conveyance belt of the automatic document feeder which concerns on the 3rd Embodiment of this invention Perspective view of the conveyor belt shown in FIG. FIG. 6 is a perspective view of a conveyance belt driving roller, a conveyance belt pressure roller, and a conveyance belt driven roller of an automatic document feeder according to a third embodiment of the present invention. 10 is a partial perspective view of the conveyance belt shown in FIG. 10 and the conveyance belt driving roller, conveyance belt pressure roller, and conveyance belt driven roller shown in FIG. FIG. 10 is a perspective view of a part of a conveyance belt driving roller, a conveyance belt pressure roller, and a conveyance belt driven roller of an automatic document feeder according to a fourth embodiment of the present invention. (A) Side view of the conveying belt of the automatic document feeder according to the fourth embodiment of the present invention and the conveying belt drive roller shown in FIG. 14 (b) The width is wider than the conveying belt shown in FIG. Side view of the long conveyor belt and the conveyor belt drive roller shown in FIG.

Explanation of symbols

10 Automatic document feeder (document feeder)
30 Conveyor belt (original feed belt)
31 Projection (convex part)
32 Protrusion line part (convex part line part)
40 Conveyor belt drive roller (belt roller)
41 Concave portion 50 Conveyor belt pressure roller (belt roller)
51 Concavity 60 Conveyor belt driven roller (belt roller)
61 Concave portion 130 Conveying belt (original feeding belt)
131 Protrusion (convex part)
132 Protrusion line part (convex part line part)
140 Conveyor belt drive roller (belt roller)
141 Concave portion 150 Conveyor belt pressure roller (belt roller)
151 Concave portion 160 Conveyor belt driven roller (roller for belt)
161 Concave portion 200 Image forming apparatus 230 Conveying belt (original feed belt)
231 Protrusion (convex part)
232 Protrusion line part (convex part line part)
233 Protrusion (convex part)
234 Projection row part (convex part row part)
235 End portion 236 End portion 240 Conveyor belt drive roller (belt roller)
241 Concave part 242 Concave part 250 Conveying belt pressure roller (belt roller)
251 Concave 252 Concave 260 Conveyor belt driven roller (belt roller)
261 Concave part 262 Concave part 340 Conveyor belt driving roller (belt roller)
341a Concave portion 342a Concave portion 350 Conveyor belt pressure roller (belt roller)
352a Concavity 360 Conveyor belt driven roller (roller for belt)
362a recess

Claims (10)

A document feeding belt for feeding a document, and a plurality of belt rollers on which the document feeding belt is hung so that a direction substantially orthogonal to the document feeding direction by the document feeding belt is an axial direction,
The document feeding belt includes a convex portion row portion in which a plurality of convex portions are intermittently arranged in the document feeding direction.
The belt roller includes a concave portion provided on an outer peripheral surface into which the convex portion is inserted,
The width of the recess is set so that at least one of the plurality of belt rollers is different from other belt rollers ,
An original feeding device characterized in that the arrangement interval of the convex portions is non-uniform . 2. The document feeding device according to claim 1, wherein the width of the concave portion of the belt roller located on the most upstream side in the document feeding direction is narrower than the width of the concave portion of the other belt roller. 2. The document feeding device according to claim 1, wherein the width of the concave portion of the belt roller located on the most downstream side in the document feeding direction is narrower than the width of the concave portion of the other belt roller. 2. The document feeder according to claim 1, wherein a width of a concave portion of a belt roller constituting a driving roller among the plurality of belt rollers is made narrower than a width of a concave portion of another belt roller. . 2. The document feeding device according to claim 1, wherein a width of a concave portion of a belt roller constituting a driven roller among the plurality of belt rollers is made narrower than a width of a concave portion of another belt roller. . 6. The document feeder according to claim 1, wherein the convex portion includes a portion that becomes narrower from a root side toward a tip side. 7. The document feeding belt according to any one of claims 1 to 6, wherein the document feeding belt includes the convex portion row portion at a portion other than an end portion in a direction substantially orthogonal to the feeding direction of the document. Document feeder. The document feeding belt includes a plurality of the convex portion row portions,
8. The document feeder according to claim 1, wherein the belt roller includes a plurality of the concave portions corresponding to the plurality of convex portion row portions. 9. 9. The belt roller according to claim 1, wherein at least one of the plurality of concave portions of the belt roller is provided in the belt roller so as to be movable in the axial direction. 10. Document feeder. An image forming apparatus comprising the document feeder according to claim 1 .

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