US20120248678A1 - Sheet conveying device that separates multi-fed sheets, and image reading apparatus - Google Patents
Sheet conveying device that separates multi-fed sheets, and image reading apparatus Download PDFInfo
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- US20120248678A1 US20120248678A1 US13/431,088 US201213431088A US2012248678A1 US 20120248678 A1 US20120248678 A1 US 20120248678A1 US 201213431088 A US201213431088 A US 201213431088A US 2012248678 A1 US2012248678 A1 US 2012248678A1
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- 238000001514 detection method Methods 0.000 claims description 31
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- 238000012545 processing Methods 0.000 description 10
- 239000011521 glass Substances 0.000 description 9
- 238000000034 method Methods 0.000 description 7
- 230000006399 behavior Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000010276 construction Methods 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000012840 feeding operation Methods 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 241001494479 Pecora Species 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
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- 239000000463 material Substances 0.000 description 1
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- 230000003287 optical effect Effects 0.000 description 1
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H3/00—Separating articles from piles
- B65H3/46—Supplementary devices or measures to assist separation or prevent double feed
- B65H3/52—Friction retainers acting on under or rear side of article being separated
- B65H3/5246—Driven retainers, i.e. the motion thereof being provided by a dedicated drive
- B65H3/5253—Driven retainers, i.e. the motion thereof being provided by a dedicated drive the retainers positioned under articles separated from the top of the pile
- B65H3/5261—Retainers of the roller type, e.g. rollers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H3/00—Separating articles from piles
- B65H3/46—Supplementary devices or measures to assist separation or prevent double feed
- B65H3/52—Friction retainers acting on under or rear side of article being separated
- B65H3/5207—Non-driven retainers, e.g. movable retainers being moved by the motion of the article
- B65H3/5215—Non-driven retainers, e.g. movable retainers being moved by the motion of the article the retainers positioned under articles separated from the top of the pile
- B65H3/5223—Retainers of the pad-type, e.g. friction pads
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H7/00—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles
- B65H7/02—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors
- B65H7/06—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors responsive to presence of faulty articles or incorrect separation or feed
- B65H7/12—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors responsive to presence of faulty articles or incorrect separation or feed responsive to double feed or separation
- B65H7/125—Controlling article feeding, separating, pile-advancing, or associated apparatus, to take account of incorrect feeding, absence of articles, or presence of faulty articles by feelers or detectors responsive to presence of faulty articles or incorrect separation or feed responsive to double feed or separation sensing the double feed or separation without contacting the articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H9/00—Registering, e.g. orientating, articles; Devices therefor
- B65H9/004—Deskewing sheet by abutting against a stop, i.e. producing a buckling of the sheet
- B65H9/006—Deskewing sheet by abutting against a stop, i.e. producing a buckling of the sheet the stop being formed by forwarding means in stand-by
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H9/00—Registering, e.g. orientating, articles; Devices therefor
- B65H9/16—Inclined tape, roller, or like article-forwarding side registers
- B65H9/166—Roller
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H2511/00—Dimensions; Position; Numbers; Identification; Occurrences
- B65H2511/10—Size; Dimensions
- B65H2511/12—Width
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H2511/00—Dimensions; Position; Numbers; Identification; Occurrences
- B65H2511/50—Occurence
- B65H2511/51—Presence
- B65H2511/514—Particular portion of element
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H2511/00—Dimensions; Position; Numbers; Identification; Occurrences
- B65H2511/50—Occurence
- B65H2511/52—Defective operating conditions
- B65H2511/524—Multiple articles, e.g. double feed
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H2553/00—Sensing or detecting means
- B65H2553/40—Sensing or detecting means using optical, e.g. photographic, elements
- B65H2553/41—Photoelectric detectors
- B65H2553/416—Array arrangement, i.e. row of emitters or detectors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H2701/00—Handled material; Storage means
- B65H2701/10—Handled articles or webs
- B65H2701/13—Parts concerned of the handled material
- B65H2701/131—Edges
- B65H2701/1315—Edges side edges, i.e. regarded in context of transport
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H2801/00—Application field
- B65H2801/03—Image reproduction devices
- B65H2801/06—Office-type machines, e.g. photocopiers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H2801/00—Application field
- B65H2801/39—Scanning
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Separation, Sorting, Adjustment, Or Bending Of Sheets To Be Conveyed (AREA)
- Controlling Sheets Or Webs (AREA)
- Delivering By Means Of Belts And Rollers (AREA)
- Sheets, Magazines, And Separation Thereof (AREA)
Abstract
A sheet conveying device which makes it possible to facilitate separation of multi-fed sheets. A separation pad and a separation roller separate sheets from a sheet bundle placed on a sheet tray, on a one-by-one basis. A pull-off roller section formed by a pair of conveying rollers nips and conveys a fed sheet. The two conveying rollers of the pull-off roller section have rotational axes extending in respective different directions. A registration roller further conveys the sheet conveyed by the pull-off roller section. One roller of the pull-off roller section is disposed such that the roller conveys a sheet in a direction in which the sheet is to be conveyed by the registration roller, and the other roller of the pull-off roller section is disposed such that the roller conveys a sheet obliquely with respect to the sheet conveying direction of the registration roller.
Description
- 1. Field of the Invention
- The present invention relates to a sheet conveying device and an image reading apparatus, and more particularly to a separating technique for separating multi-fed sheets when multi-feed occurs in a conveying mechanism that conveys sheets while separating the sheets one by one from a sheet bundle placed on a sheet tray.
- 2. Description of the Related Art
- In an image reading apparatus provided with a conventional sheet conveying device, when two or more sheets are conveyed in a state overlapping each other, i.e. when multi-feed occurs, a sheet jam or defective image reading can take place. In either case, a user has to carry out work e.g. for removing sheets and setting sheets again, and hence the apparatus is inevitably stopped during execution of the work. To solve this problem, there has been proposed a sheet conveying device configured to be operable when multi-feed is detected, to convey multi-fed sheets in the reverse direction, i.e. toward a sheet tray by a predetermined distance and separate the sheets one from another using a separation mechanism again (see e.g. U.S. Patent Publication No. 5,384,631).
- In the above-described conventional sheet conveying device, however, multi-feed occurs due to high adhesiveness between sheets, so that re-use of the same separation mechanism cannot reliably ensure separation of the sheets.
- The present invention provides a sheet conveying device and an image reading apparatus, which make it possible to facilitate separation of multi-fed sheets to thereby improve sheet conveyance efficiency.
- In a first aspect of the present invention, there is provided a sheet conveying device comprising a sheet feed unit configured to feed a sheet from a plurality of sheets placed on a sheet tray, on a one-by-one basis, by separating the sheets, a first conveying unit having a pair of conveying rollers configured to convey the sheet fed from the sheet feed unit in a state nipped therebetween, the conveying rollers having rotational axes extending in respective different directions, and a second conveying unit configured to further convey the sheet conveyed by the first conveying unit, wherein one roller of the conveying roller pair is disposed such that the roller conveys the fed sheet in a direction in which the sheet is to be conveyed by the second conveying unit, and the other roller of the conveying roller pair is disposed such that the roller conveys the sheet obliquely with respect to the sheet conveying direction of the second conveying unit.
- In a second aspect of the present invention, there is provided an image reading apparatus comprising a sheet tray on which a plurality of sheets are placed, a sheet feed unit configured to feed a sheet from the sheets placed on the sheet tray, on a one-by-one basis, by separating the sheets, a first conveying unit having a pair of conveying rollers configured to convey the sheet fed from the sheet feed unit in a state nipped therebetween, the conveying rollers having rotational axes extending in respective different directions, a second conveying unit configured to further convey the sheet conveyed by the first conveying unit, and a reading unit configured to read an image from the sheet conveyed by the second conveying unit, wherein one roller of the conveying roller pair is disposed such that the roller conveys the fed sheet in a direction in which the sheet is to be conveyed by the second conveying unit, and the other roller of the conveying roller pair is disposed such that the roller conveys the sheet obliquely with respect to the sheet conveying direction of the second conveying unit.
- According to the present invention, one of the pair of conveying rollers different in axial direction is disposed such that the roller performs sheet conveyance in a sheet conveying direction, and the other roller of the conveying roller pair is disposed such that the roller performs sheet conveyance obliquely with respect to the sheet conveying direction. This makes it easy to separate the multi-fed sheets, and makes it possible to improve sheet conveying efficiency.
- Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
-
FIG. 1 is a schematic view of an image reading apparatus provided with a sheet conveying device according to a first embodiment of the present invention. -
FIG. 2 is a schematic block diagram of the control systems of an ADF and a reader section appearing inFIG. 1 and an image controller. -
FIGS. 3A and 3B are schematic views of a pull-off roller section appearing inFIG. 1 , in whichFIG. 3A schematically shows the pull-off roller section as viewed in a direction indicated by an arrow A in FIG. - 1, and
FIG. 3B schematically shows the pull-off roller section as viewed in a direction indicated by an arrow B inFIG. 1 . -
FIGS. 4A to 4D are views useful in explaining the behavior of a sheet in the pull-off roller section. -
FIG. 5 is a flowchart of a sheet separation process executed in the first embodiment by a CPU using the pull-off roller section. -
FIGS. 6A to 6C are views useful in explaining a multi-feed determination method. -
FIG. 7 is a diagram illustrating different degrees of change in sheet width detected on sheets by a sheet width detection section. -
FIGS. 8A to 8D are views useful in explaining push-in operation performed by the pull-off roller section to push a sheet into a registration roller. -
FIG. 9 is a partially see-through view of an ADF, as viewed from above, of an image reading apparatus provided with a sheet conveying device according to a second embodiment of the present invention. -
FIGS. 10A to 10C are views useful in explaining the behavior of a sheet in the pull-off roller section. - The present invention will now be described in detail below with reference to the accompanying drawings showing embodiments thereof.
-
FIG. 1 is a schematic view of an image reading apparatus provided with a sheet conveying device according to a first embodiment of the present invention. - In
FIG. 1 , the image reading apparatus comprises an automatic document feeder (hereinafter acronymized as “the ADF”) 100 and an image reading section (hereinafter referred to as “the reader section”) 200. The ADF 100 has asheet tray 30 on which a sheet bundle S formed by one or more sheets is placed. Before the start of a sheet feeding operation, the sheets of the sheet bundle S are restricted by aseparation pad 21 from entering theADF 100. When the sheet feeding operation is started, asheet feed roller 1 urged on the sheet bundle S is driven to pull the sheets into theADF 100, and only an uppermost sheet of the sheet bundle S is fed onto a conveying path by theseparation pad 21 and aseparation roller 2. - In actuality, a case where the
separation pad 21 and theseparation roller 2 fail to separate only an uppermost sheet can occur depending on a sheet type or due to a difference in surface frictional force between sheets. In the present embodiment, sheets which are not separated one from another at the above-mentioned time and are fed in a state overlapping each other will be referred to as “multi-fed sheets”. - A
separation sensor 10 is disposed downstream of theseparation pad 21 and theseparation roller 2 in the sheet conveying direction. Theseparation sensor 10 is used for detection of an interval between sheets after separation, which is performed based on an output therefrom. Downstream of theseparation sensor 10 is disposed a sheetwidth detection section 11 comprising a plurality of sheet detectors arranged in a direction intersecting with (e.g. orthogonal to) the sheet conveying direction (hereinafter simply referred to as “the conveying direction”). The sheetwidth detection section 11 detects the width of each fed sheet based on whether or not the fed sheet has been detected by the sheet detection sensors in predetermined timing before the sheet is brought into abutment with aregistration roller 4. Note that the sheetwidth detection section 11 may be implemented by an array sensor, such as a CCD or a CIS. - A sheet having passed the sheet
width detection section 11 is conveyed by a pull-offroller section 3 and is brought into abutment with theregistration roller 4. At a time point when the sheet reaches theregistration roller 4, theregistration roller 4 is in a state not being driven but at rest, so that the leading edge of the sheet is prevented from being advanced. The sheet in this state is pushed toward theregistration roller 4 by pushing operation of the pull-offroller section 3, whereby it is warped. Even when the conveying process up to this time has brought the sheet into a skewed state where the leading edge of the sheet is in an oblique relation to the conveying direction, the skew of the sheet is corrected by warping the sheet with its leading edge held in abutment with theregistration roller 4. Then, theregistration roller 4 is rotated to convey the sheet to afirst conveying roller 5 and aroller 7, whereafter the sheet is conveyed by these rollers onto aplaten glass 201. Thereader section 200 reads a front-surface image from the sheet through theplaten glass 201. - Then, the sheet is conveyed by a
second conveying roller 6, and is passed through between aroller 16 and a back surface-reading glass 18. Then, the sheet is discharged onto adischarge tray 31 via adischarge flapper 20 and adischarge roller pair 8. - A back-surface
image reading section 17 is a unit configured to optically read image information from a sheet and output an image signal subjected to photoelectric conversion to a subsequent stage. The back-surfaceimage reading section 17 is disposed on the back side of the back surface-reading glass 18 opposed to theroller 16. The back-surfaceimage reading section 17 reads a back-surface image on the sheet while the sheet is passing through a clearance between theroller 16 and the back surface-reading glass 18. - Each of
sheet detection sensors - Similarly, the
reader section 200 is a unit configured to optically read image information from a sheet and output an image signal subjected to photoelectric conversion to a subsequent stage. Thereader section 200 comprises theplaten glass 201, aplaten glass 202, ascanner unit 209, asecond mirror 205, athird mirror 206, alens 207, and a CCD (charge coupled device) 208. Note that thescanner unit 209 comprises an illuminatinglamp 203 and afirst mirror 204. - In reading a front-surface image from a sheet, the
scanner unit 209 is moved to a position below theplaten glass 201 in advance. Then, the illuminatinglamp 203 is turned on in this state, and reflected light from the front surface of the sheet passing on the moving reading glass is guided to thelens 207 via the first tothird mirrors CCD 208. After this process, the front-surface image from the sheet is photoelectrically converted to a digital image signal by theCCD 208. -
FIG. 2 is a schematic block diagram of the control systems of theADF 100 and thereader section 200 appearing inFIG. 1 and animage controller 300. - In the
reader section 200, a central processing unit (hereinafter acronymized as “the CPU”) 251 controls theADF 100 and thereader section 200. Connected to thereader section 200 are aROM 252 as a memory for storing programs and aRAM 253 as a memory for providing work areas. TheROM 252 stores control programs for thereader section 200 and theADF 100, and theRAM 253 stores input data for use in control and working data. - Connected to the
CPU 251 are amotor driver section 256 as a driver circuit for driving an optical motor that moves thescanner unit 209 and a front-surfaceimage reading section 260. The front-surfaceimage reading section 260 comprises the illuminatinglamp 203 and theCCD 208 mentioned above, and asignal controller 259 for converting an output from theCCD 208 to a digital image signal. TheCPU 251 controls themotor driver section 256 and the front-surfaceimage reading section 260 to read an image from the front surface of an original. - A sheet
interval correction section 254 corrects parameters of thesignal controller 259 according to a sheet interval (i.e. an interval between the trailing edge of a preceding sheet and the leading edge of the following sheet) between fed sheets. Although in the present embodiment, the sheet interval is handled as a time parameter, it may be handled as a distance parameter. Animage processing section 255 processes an image signal read by the front-surfaceimage reading section 260 or the back-surfaceimage reading section 17, generates a timing signal, and transmits the signals to theimage controller 300. Animage buffer 261 is controlled by theimage processing section 255. Theimage buffer 261 is provided for temporarily storing the image signal read by the front-surfaceimage reading section 260 or the back-surfaceimage reading section 17. - The
ADF 100 is connected to the input/output ports of theCPU 251. Connected to the output port are amotor group 103 for driving the conveying rollers, asolenoid group 101, and aclutch group 102. On the other hand, connected to the input port are asensor group 104 for generating sheet conveying timing signals and the sheetwidth detection section 11 for detecting the size of each sheet during sheet conveyance. - The
CPU 251 executes a control program stored in theROM 252, to thereby control sheet conveying operation in theADF 100. The back-surfaceimage reading section 17 comprises an illuminatinglamp 307 for back-surface image reading, a CIS (contact image sensor) 308, and asignal controller 107. The back-surfaceimage reading section 17 is connected to theCPU 251. The back-surfaceimage reading section 17 reads a back-surface image from a sheet according to a control signal from theCPU 251 and transfers the read image to theimage processing section 255. - Image signals stored in the
image buffer 261 are read out into theimage processing section 255 in synchronism with a timing signal, and is sequentially transferred to theimage controller 300 via acontroller interface section 350. - The
image controller 300 has aCPU 301, aROM 302, and aRAM 303 for image control, independently of thereader section 200. The image signals delivered from theimage processing section 255 to theimage controller 300 are subjected to input/output control by an image input/output unit 304, and are sequentially stored and accumulated as image data in animage memory 305. - An
image processing section 310 performs various kinds of image processing on image signals input from the image input/output unit 304 or image data accumulated in theimage memory 305. Aconsole section 309 is capable of notifying a user of the status of the apparatus by screen display. Further, theconsole section 309 receives operation instructions given by the user to the apparatus. In response to the instructions received via theconsole section 309, theCPU 301 reads out image data from theimage memory 305 and executes processing e.g. for transferring an image and information to an external apparatus or a personal computer through a telephone line or a network connected to anexternal interface 312. - Although in the present embodiment, the front-surface image reading section of the
reader section 200 is provided with the CCD and the back-surface image reading section of theADF 100 is provided with the CIS, this is not limitative, but any other sensor which is capable of image reading may be used in place of the CCD or the CIS. - Next, the pull-off
roller section 3 will be described in detail. -
FIGS. 3A and 3B are schematic views of the pull-offroller section 3 appearing inFIG. 1 .FIG. 3A schematically shows the pull-offroller section 3 as viewed in a direction indicated by an arrow A inFIG. 1 , andFIG. 3B schematically shows the same as viewed in a direction indicated by an arrow B inFIG. 1 . - The pull-off
roller section 3 comprises a conveying roller pair formed by upper andlower rollers upper roller 3 a and thelower roller 3 b rotate with a sheet P nipped therebetween, to thereby convey the sheet P in the conveying direction. Theupper roller 3 a and thelower roller 3 b are driven by respective different motors (included in themotor group 103 inFIG. 2 ). - The
upper roller 3 a and thelower roller 3 b have respective rotational axes extending in different directions, respectively. Specifically, thelower roller 3 b is a conveying roller having a rotational axis extending in the same direction as the rotational axes of thesheet feed roller 1 and theseparation roller 2 and that of the registration roller (i.e. in the direction orthogonal to the sheet conveying direction) and configured to convey a sheet P straight in the downstream direction. On the other hand, theupper roller 3 a is an obliquely conveying roller having a rotational axis horizontally inclined with respect to the direction orthogonal to the sheet conveying direction. In the present embodiment, the inclination angle of theupper roller 3 a with respect to thelower roller 3 b is set to 20 degrees. Note that the inclination angle can be changed according e.g. to the material, size, or frictional force of a roller, and therefore it is not limited to 20 degrees. Further, the directional relationship between the rotational axis of theupper roller 3 a and that of thelower roller 3 b may be reversed. - The
upper roller 3 a and thelower roller 3 b are configured to apply respective different conveying forces to a sheet. The reason for this will be described hereinafter. - Further, the
upper roller 3 a and thelower roller 3 b are constructed such that switching can be performed between contact and separation states. This is because if the two rollers different in axial direction are rotated in direct contact with each other in a state where no sheet exists therebetween, abrasion or deformation can occur to cause damage to the rollers. Switching between contact and separation between theupper roller 3 a and thelower roller 3 b is performed by driving a specific solenoid of thesolenoid group 101 according to a control signal from theCPU 251. In short, the specific solenoid functions as a switching unit for switching between contact and separation between theupper roller 3 a and thelower roller 3 b. Note that any other construction and method may be employed for switching between contact and separation between theupper roller 3 a and thelower roller 3 b. - Next, a description will be given, with reference to
FIGS. 4A to 4D , of the behavior of a sheet P in the pull-offroller section 3. Although inFIGS. 4A to 4D , only the obliquely conveying roller (upper roller 3 a) is shown as the pull-offroller section 3, it is assumed that the conveying roller (lower roller 3 b), not shown, is disposed at a location opposed to the obliquely conveying roller. Further, in the vicinity of the pull-offroller section 3 is disposed the sheetwidth detection section 11 for detecting sheet width in the direction intersecting with the sheet conveying direction of the registration roller 4 (or thelower roller 3 b). -
FIG. 4A shows a state before the sheet P reaches the pull-offroller section 3. In the state shown inFIG. 4A , it is not apparent whether the sheet P has been conveyed in a state normally separated as a single sheet or in a multi-fed state in which the sheet P overlaps another sheet. When the sheet P reaches the pull-offroller section 3, control is performed to switch theupper roller 3 a and thelower roller 3 b from the separation state to the contact state. - Now, a description will be given of conveying forces of the respective upper and
lower rollers lower motors - First, a case where the sheet P has been conveyed as a single sheet will be described.
-
FIG. 4B shows an example of a state where the conveying forces have been set in advance such that the conveying force of theupper roller 3 a is larger than that of thelower roller 3 b. In this case, since the conveying force of theupper roller 3 a is larger, the sheet P is skewed and conveyed obliquely. On the other hand,FIG. 4C shows a state where the conveying forces have been set in advance such that the conveying force of theupper roller 3 a is smaller than that of thelower roller 3 b. In this case, since the conveying force of thelower roller 3 b is larger, the sheet P is conveyed straight forward. - Next, a description will be given of a case where the sheet P has been conveyed in a state overlapping another sheet.
- When the
upper roller 3 a and thelower roller 3 b are switched to the contact state, the upper sheet P of the multi-fed sheets receives a force acting in an oblique direction from theupper roller 3 a. On the other hand, a lower sheet Pa receives a force acting straight in the conveying direction from thelower roller 3 b. As a consequence, a twist occurs between the upper sheet and the lower sheet of the multi-fed sheets, which causes separation between the sheet P and the sheet Pa fed together with the sheet P, as shown inFIG. 4D . In this case, whichever of theupper roller 3 a and thelower roller 3 b applies a larger force, it is known that the behavior for separation is substantially the same. Note that a skew of a sheet caused by the conveying force of theupper roller 3 a is corrected by theregistration roller 4. A sheet having its skew corrected and conveyed by theregistration roller 4 may have its position in a transverse direction orthogonal to the conveying direction adjusted by shifting of theregistration roller 4 in its axial direction. -
FIG. 5 is a flowchart of a sheet separation process executed in the present embodiment by theCPU 251 using the pull-offroller section 3. - First, in response to a reading operation start instruction from the
image controller 300, theCPU 251 performs control such that a sheet pickup operation for picking up a sheet on the ADF is started (step S800). Specifically, thesheet feed roller 1 is turned on whereby it is driven and lowered into contact with the upper surface of a sheet bundle S to convey sheets P to theseparation roller 2. Theseparation roller 2 attempts to separate an uppermost sheet P and then conveys the separated sheet P into the apparatus. - Then, when a predetermined time period elapses after the start of the pickup operation, the
CPU 251 causes the sheetwidth detection section 11 to start sheet width detection (step S801). - Thereafter, the
CPU 251 waits until the sheet P reaches the pull-off roller section 3 (step S802). Immediately before the sheet P reaches the pull-offroller section 3, theCPU 251 switches the pull-offroller section 3 held in the separation state in advance to the contact state, and causes rotation of theupper roller 3 a and thelower roller 3 b (step S803). Then, theCPU 251 drivingly controls theupper roller 3 a and thelower roller 3 b to pull off (separate) the sheet P as shown inFIG. 4D (step S803). - Next, the
CPU 251 terminates the pickup operation in timing substantially synchronous with execution of the step S803 to thereby facilitate the sheet pull-off operation by the pull-off roller section 3 (step S804). Specifically, theCPU 251 stops driving of thesheet feed roller 1 to allow the same to move upward away from the sheet bundle S, and stops driving of theseparation roller 2 at the same time to thereby facilitate the sheet pull-off operation by the pull-offroller section 3. - Then, the
CPU 251 determines, based on a change in sheet width detected by the sheetwidth detection section 11, whether or not the sheet P currently conveyed is in a state overlapping another sheet (step S805). - Now, a description will be given of determination of multi-feed of sheets with reference to
FIGS. 6A to 6C . - In the present embodiment, multi-feed determination is performed based on a sheet width detected by the sheet
width detection section 11. -
FIG. 6A shows an example of a state before a sheet P reaches the pull-offroller section 3. - In the illustrated example, a detected sheet width L0 of the sheet P detected by the sheet
width detection section 11 is the same as the actual sheet width of the sheet P. -
FIG. 6B shows a case where under a condition that the conveying force of theupper roller 3 a is larger than that of thelower roller 3 b, a single sheet P reaches the pull-offroller section 3, and since the conveying force of theupper roller 3 a is larger than that of thelower roller 3 b, the single sheet P is brought into a skewed state. - Now, a detected sheet width of the sheet P detected by the sheet
width detection section 11 in theFIG. 6B example is represented by L1. In this example, since the sheet P is caused to be skewed, L1 is larger than L0 (L1>L0). Note that under a condition that the conveying force of theupper roller 3 a is smaller than that of thelower roller 3 b, if a single sheet P reaches the pull-offroller section 3, the sheet P advances straight forward. Therefore, in this case, a detected sheet width of the sheet P detected by the sheetwidth detection section 11 is equal to L0 similarly toFIG. 6A . -
FIG. 6C shows a state where multi-fed sheets reach the pull-offroller section 3 and the sheets start to be separated. - Now, a detected sheet width of the sheet P detected by the sheet
width detection section 11 in theFIG. 6C example is represented by L2. The apparent sheet width L1 or L2 detected by the sheetwidth detection section 11 changes in the sheet conveyance and separation process.FIG. 7 is a graph showing the different degrees of change in each sheet width detected by the sheetwidth detection section 11 after each sheet reaches the pull-offroller section 3. In theFIG. 7 graph, the vertical axis represents detected sheet width, and the horizontal axis represents elapsed time t. A time point t0 indicates a timing in which the sheetwidth detection section 11 detects the sheet width at a leading end of the sheet, and a time point t1 indicates a timing in which the sheet reached the pull-offroller section 3. - Referring to
FIG. 7 , when the sheet is single, the detected sheet width L1 is constant after the leading end of the sheet has started to be detected by the sheetwidth detection section 11 until the sheet reaches the pull-offroller section 3. After the sheet reaches the pull-offroller section 3, the detected sheet width L1 of the single sheet, under the condition that the conveying force of theupper roller 3 a is set to be larger than that of thelower roller 3 b, progressively increases as the sheet is further skewed. Note that the increase in the detected sheet width L1 stops when the skew of the sheet P becomes equal in value to the inclination of theupper roller 3 a. On the other hand, when sheets are multi-fed, an upper sheet P is conveyed while being skewed, whereas a lower sheet Pa is conveyed straight. For this reason, the amount of change in the detected sheet width L2, i.e. the inclination of the graph associated with the detected sheet width L2 is larger than that of the detected sheet width L1. Note that the value of the detected sheet width L2 is maximized when the skew of the sheet P becomes equal in value to the inclination of theupper roller 3 a. - Therefore, when it is determined, by referring to time-varying change in the sheet width detected after a sheet P reaches the pull-off
roller section 3, that the degree of the change has exceeded e.g. a predetermined threshold value T, it is possible to judge that the conveyed sheet P is in a state overlapping another sheet. - Although in the present embodiment, multi-feed determination is performed based on a change in sheet width detected by a sheet width detection sensor, this is not limitative, but a dedicated sensor for detecting multi-feed may be additionally provided.
- Referring again to
FIG. 5 , if it is determined in a step S806 that multi-feed has occurred, theCPU 251 stops driving of thelower roller 3 b of the pull-offroller section 3 and performs sheet conveyance by driving theupper roller 3 a alone (step S807). As a consequence, only the upper one of the sheets to be separated is conveyed first. Then, theCPU 251 waits until the upper sheet reaches the registration roller 4 (step S808). When the upper sheet reaches theregistration roller 4 and is pushed against theregistration roller 4 to have the skew of the upper sheet corrected, theCPU 251 causes theupper roller 3 a to be spaced from thelower roller 3 b and stops the driving of theupper roller 3 a (step S809). - Now, a description will be given, with reference to
FIGS. 8A to 8D , of the push-in operation performed by the pull-offroller section 3 for pushing a sheet into theregistration roller 4. -
FIG. 8A shows a skewed state of the sheet P before reaching theregistration roller 4. Note that the upper portion of each ofFIGS. 8A to 8D shows theregistration roller 4, the pull-offroller section 3, and the sheet P, as viewed from above, and the lower portion shows these as viewed just from a side. - Note that in
FIGS. 8A to 8D hatching provided on a roller indicates that the roller is in a driven state. - In a state shown in
FIG. 8B , the leading edge of the sheet P has reached theregistration roller 4, but since theregistration roller 4 is at rest, the sheet P cannot advance. On the other hand, the sheet P is pushed from behind by the pull-offroller section 3, so that the sheet P starts to be warped. -
FIG. 8C shows a state where the push-in operation by the pull-offroller section 3 has been completed and the sheet P has been warped. In this stage, the leading edge of the sheet has been brought into abutment with theregistration roller 4 by sheet stress and restriction of conveying guides (not shown), whereby the skew of the sheet has been eliminated. Theregistration roller 4 is driven for rotation in predetermined timing to convey the sheet having its skew eliminated downstream toward an image reading position, as shown inFIG. 8D . - Referring again to
FIG. 5 , in a step S810, theCPU 251 waits until the sheet P is conveyed downstream by theregistration roller 4 and the separation is completed. The completion of the separation is judged from time elapsed after the start of driving of theregistration roller 4 until passing of the trailing end of the upper sheet through theregistration roller 4. After confirming completion of the sheet separation, theCPU 251 stops driving of theregistration roller 4, terminates the spacing of theupper roller 3 a from thelower roller 3 b, and restarts driving of both the upper andlower rollers registration roller 4, and then proceeds to a step S812. Processing in the step S812 et seq. is the same as in a case where it is determined in the step S806 that multi-feed has not occurred. - If it is determined in the step S806 that multi-feed has not occurred, the
CPU 251 continues sheet conveyance to cause the sheet to reach theregistration roller 4. Then, after confirming arrival of the sheet at the registration roller 4 (step S812), theCPU 251 stops driving of the pull-offroller section 3 in a predetermined timing to thereby return theupper roller 3 a and thelower roller 3 b to the separation state (step S813). Finally, theCPU 251 stops operation of the sheet width detection section 11 (step S814) to thereby terminate sheet width detection and multi-feed detection based on time-varying change of a width detection signal. This completes a sequence of sheet-pulling off operations. - Although in the sheet conveying device of the present embodiment, the conveying force of the
lower roller 3 b configured to convey a sheet in the same conveying direction as theregistration roller 4 does is set to be smaller than that of theupper roller 3 a, theupper roller 3 a may have a smaller conveying force than thelower roller 3 b. - As described above, according to the above-described embodiment, one roller of the pair of conveying rollers different in axial direction is disposed such that it conveys a sheet in the conveying direction, and the other roller is disposed such that it conveys a sheet obliquely with respect to the conveying direction so as to separate multi-fed sheets. This makes it possible to facilitate separation of multi-fed sheets to thereby improve sheet conveyance efficiency. Further, it is not required to stop the apparatus, and hence it is possible to further improve sheet conveyance efficiency.
- In the above-described embodiment, since the
registration roller 4 is disposed downstream of the pull-offroller section 3 in the conveying direction, it is determined in the steps S808 and S812 whether or not a sheet has reached theregistration roller 4. However, a roller that can be disposed downstream of the pull-off roller section is not limited to the registration roller, but another kind of roller may be disposed downstream of the pull-off roller section. - Next, a second embodiment of the present invention will be described with reference to drawings.
-
FIG. 9 is a partially see-through view of anADF 1100, as viewed from above, of an image reading apparatus provided with a sheet conveying device according to the second embodiment of the present invention. - As shown in
FIG. 9 , theADF 1100 has asheet tray 1030 on which a sheet bundle S formed by one or more sheets can be placed. Thesheet tray 1030 is disposed such that a front side (lower side as viewed inFIG. 9 ) thereof obliquely extends in an expanding manner, i.e. along with asheet guide member 1040 provided in a manner angled with respect to a conveying direction (left-right direction as viewed inFIG. 9 ). This configuration of thesheet tray 1030 enables a user standing in front of the apparatus (at the lower side as viewed inFIG. 9 ) to place the sheet bundle S on thesheet tray 1030 without stretching out his/her arms. In short, the user can place a sheet bundle on thesheet tray 1030 in an ergonomically comfortable fashion. - At the rear (upper side as viewed in
FIG. 9 ) of thesheet tray 1030, there is a space formed in a manner extending along the conveying direction. The space is thus formed so as to enable the trailing end of a sheet, which was pulled in obliquely with respect to the conveying direction from the sheet bundle S placed along the front side of thesheet tray 1030, to freely move when the sheet turns its direction to the conveying direction. - Each of
separation rollers 1002 has its pull-in angle set such that the axis of theseparation roller 1002 is directed in a direction orthogonal to the gradient of a portion of thesheet guide member 1040 with which a sheet bundle side is brought into contact. The cross-sectional view of theADF 1100 is substantially the same asFIG. 1 as described in the first embodiment, and therefore it is omitted. Note that in addition to thesheet tray 30 appearing inFIG. 1 , thesheet feed roller 1, theseparation pad 21, theseparation roller 2, and theseparation sensor 10 are arranged obliquely according to the angle of thesheet tray 1030 with respect to the conveying direction. - A conveying roller pair of a pull-in
roller section 1003 is disposed such that an upper roller as one of the rollers conveys a sheet in the sheet conveying direction and a lower roller as the other of the rollers conveys a sheet in the same direction as a direction in which a sheet bundle S on the sheet tray is pulled in. In short, the lower roller is disposed so as to convey a sheet obliquely with respect to the sheet conveying direction. - The conveying forces of the two conveying rollers of the pull-in
roller section 1003 are set such that the conveying force of the upper roller for conveying a sheet in the conveying direction is larger than that of the lower roller. - Note that the image reading apparatus of the present embodiment is identical in configuration to that of the first embodiment, and therefore a control block diagram thereof and description thereof are omitted.
- Next, the behavior of a sheet P in the pull-in
roller section 1003 will be described with reference toFIGS. 10A to 10C . Although not shown, the lower roller is disposed such that the roller conveys a sheet in the direction in which the sheet is pulled in from thesheet tray 1030. A sheetwidth detecting section 1011 is disposed in a manner orthogonal to thesheet guide 1040, and has the same construction as that of the sheetwidth detection section 11 in the first embodiment. -
FIG. 10A shows a state before the sheep P reaches the pull-inroller section 1003. Similarly to the first embodiment, in this state, it is not apparent whether or not the sheet P has been conveyed as a single sheet or in a state overlapping another sheet. At this time point, the pull-inroller section 1003 is held in the separation state as in the first embodiment. -
FIG. 10B shows a case where the sheet P has been conveyed as a single sheet. In this case, the pull-inroller section 1003 is switched to the contact state, but since the conveying force of the upper roller is larger, the sheet P has its direction turned in the sheet conveying direction. -
FIG. 10C shows a case where the sheet P is in a state overlapping another sheet. In this case as well, the pull-inroller section 1003 is switched to the contact state in timing synchronous with arrival of the sheet P. In the present case, the upper one of the multi-fed sheets receives a force from the upper roller whereby it is directed in the conveying direction. On the other hand, the lower sheet receives a force from the lower roller so that it remains directed in the sheet feed direction. As a consequence, a twist occurs between the upper and lower ones of the multi-fed sheets, whereby separation of the multi-fed sheets is achieved. - Control of the pull-in
roller section 1003 in the present embodiment is performed following the same control procedure as in the first embodiment, and therefore description thereof is omitted. - As described above, also in the sheet conveying device having the sheet tray extending in a manner expanding toward the front side so as to facilitate user operation for placing sheets on the sheet tray, the pull-in
roller section 1003 is formed by the pair of rollers different in conveying direction. This makes it possible to switch the sheet conveying direction to the direction of conveyance by a downstream conveying roller (e.g. the registration roller 4) and positively perform separation of multi-fed sheets. - Although in the above-described first and second embodiments, the image reading apparatus provided with the sheet conveying device is described, this is not limitative, but the present invention is also applicable to an image forming apparatus including an image forming section (printer section) in addition to an image reading section having the above-described construction.
- While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
- This application claims priority from Japanese Patent Application No. 2011-069970 filed Mar. 28, 2011, and Japanese Patent Application No. 2012-064026 filed Mar. 21, 2012, which are hereby incorporated by reference herein in their entirety.
Claims (10)
1. A sheet conveying device comprising:
a sheet feed unit configured to feed a sheet from a plurality of sheets placed on a sheet tray, on a one-by-one basis, by separating the sheets;
a first conveying unit having a pair of conveying rollers configured to convey the sheet fed from said sheet feed unit in a state nipped therebetween, the conveying rollers having rotational axes extending in respective different directions; and
a second conveying unit configured to further convey the sheet conveyed by said first conveying unit,
wherein one roller of the conveying roller pair is disposed such that the roller conveys the fed sheet in a direction in which the sheet is to be conveyed by said second conveying unit, and the other roller of the conveying roller pair is disposed such that the roller conveys the sheet obliquely with respect to the sheet conveying direction of said second conveying unit.
2. The sheet conveying device according to claim 1 , further comprising a multi-feed determination unit configured to determine whether or not multi-feed has occurred in which the sheet conveyed by said first conveying unit is in a state overlapping another sheet, and
a control unit configured to be operable when said multi-feed determination unit determines that multi- feed has occurred, to perform control such that rotation of one roller of the conveying roller pair nipping the multi-fed sheets is stopped or decelerated.
3. The sheet conveying device according to claim 2 , further comprising a sheet width detection unit disposed close to said first conveying unit and configured to detect a sheet width in a direction intersecting with a sheet conveying direction of said first conveying unit, and
wherein said multi-feed determination unit determines whether or not multi-feed has occurred, based on a change in the sheet width which is detected by said sheet width detection unit during sheet conveyance by said first conveying unit.
4. The sheet conveying device according to claim 3 , wherein said sheet width detection unit comprises a plurality of detectors arranged in the direction intersecting with the sheet conveying direction of said second conveying unit.
5. The sheet conveying device according to claim 1 , further comprising a switching unit configured to switch the conveying roller pair between a contact state in which one roller and the other roller of the conveying roller pair are brought into contact with each other and a separation state in which the one roller and the other roller of the conveying roller pair are spaced from each other.
6. The sheet conveying device according to claim 5 , wherein in synchronism of the sheet reaching the conveying roller pair, said switching unit switches the conveying roller pair held in the separation state in advance to the contact state.
7. The sheet conveying device according to claim 1 , wherein the one roller of the conveying roller pair and the other of the conveying roller pair are configured to have respective different conveying forces.
8. The sheet conveying device according to claim 7 , further comprising a guide member for guiding the plurality of sheets which are placed on the sheet tray, a portion of said guide member with which a sheet bundle side is brought into contact being angled with respect to the sheet conveying direction.
9. The sheet conveying device according to claim 8 , wherein a direction in which a sheet is conveyed by the one roller of the conveying roller pair is the same as the sheet conveying direction of said second conveying unit, and the conveying force of the one roller of the conveying roller pair is larger than the conveying force of the other roller of the conveying roller pair.
10. An image reading apparatus comprising:
a sheet tray on which a plurality of sheets are placed;
a sheet feed unit configured to feed a sheet from the sheets placed on said sheet tray, on a one-by-one basis, by separating the sheets;
a first conveying unit having a pair of conveying rollers configured to convey the sheet fed from said sheet feed unit in a state nipped therebetween, the conveying rollers having rotational axes extending in respective different directions;
a second conveying unit configured to further convey the sheet conveyed by said first conveying unit; and
a reading unit configured to read an image from the sheet conveyed by said second conveying unit,
wherein one roller of the conveying roller pair is disposed such that the roller conveys the fed sheet in a direction in which the sheet is to be conveyed by said second conveying unit, and the other roller of the conveying roller pair is disposed such that the roller conveys the sheet obliquely with respect to the sheet conveying direction of said second conveying unit.
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2011-069970 | 2011-03-28 | ||
JP2011069970 | 2011-03-28 | ||
JP2012064026A JP2012214294A (en) | 2011-03-28 | 2012-03-21 | Sheet conveying device for separating multi-fed sheets, and image reading apparatus |
JP2012-064026 | 2012-03-21 |
Publications (1)
Publication Number | Publication Date |
---|---|
US20120248678A1 true US20120248678A1 (en) | 2012-10-04 |
Family
ID=46926141
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/431,088 Abandoned US20120248678A1 (en) | 2011-03-28 | 2012-03-27 | Sheet conveying device that separates multi-fed sheets, and image reading apparatus |
Country Status (2)
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US (1) | US20120248678A1 (en) |
JP (1) | JP2012214294A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20210155430A1 (en) * | 2019-11-27 | 2021-05-27 | Canon Kabushiki Kaisha | Sheet conveying apparatus and image reading apparatus |
US11247860B2 (en) * | 2018-06-27 | 2022-02-15 | Canon Kabushiki Kaisha | Sheet conveying apparatus, image reading apparatus, and image forming apparatus |
US11518634B2 (en) * | 2021-01-27 | 2022-12-06 | Canon Kabushiki Kaisha | Reading apparatus and image forming system |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6957193B2 (en) * | 2017-05-02 | 2021-11-02 | キヤノン株式会社 | Sheet transfer device and image forming device |
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JPS5811447A (en) * | 1981-07-10 | 1983-01-22 | Fujitsu Ltd | Control method of separator unit in paper sheet feeding machine |
US4821049A (en) * | 1987-12-02 | 1989-04-11 | Pitney Bowes Inc. | Substrate transport apparatus, especially for mail handling |
US20070023996A1 (en) * | 2002-06-04 | 2007-02-01 | Canon Kabushiki Kaisha | Double feed detection method and double feed detection apparatus of sheet materials |
US7441772B2 (en) * | 2005-03-22 | 2008-10-28 | Canon Kabushiki Kaisha | Sheet-conveying device |
US20100102504A1 (en) * | 2007-10-05 | 2010-04-29 | Canon Kabushiki Kaisha | Sheet conveyance apparatus and image forming apparatus |
-
2012
- 2012-03-21 JP JP2012064026A patent/JP2012214294A/en active Pending
- 2012-03-27 US US13/431,088 patent/US20120248678A1/en not_active Abandoned
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JPS5811447A (en) * | 1981-07-10 | 1983-01-22 | Fujitsu Ltd | Control method of separator unit in paper sheet feeding machine |
US4821049A (en) * | 1987-12-02 | 1989-04-11 | Pitney Bowes Inc. | Substrate transport apparatus, especially for mail handling |
US20070023996A1 (en) * | 2002-06-04 | 2007-02-01 | Canon Kabushiki Kaisha | Double feed detection method and double feed detection apparatus of sheet materials |
US7441772B2 (en) * | 2005-03-22 | 2008-10-28 | Canon Kabushiki Kaisha | Sheet-conveying device |
US20100102504A1 (en) * | 2007-10-05 | 2010-04-29 | Canon Kabushiki Kaisha | Sheet conveyance apparatus and image forming apparatus |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
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US11247860B2 (en) * | 2018-06-27 | 2022-02-15 | Canon Kabushiki Kaisha | Sheet conveying apparatus, image reading apparatus, and image forming apparatus |
US20210155430A1 (en) * | 2019-11-27 | 2021-05-27 | Canon Kabushiki Kaisha | Sheet conveying apparatus and image reading apparatus |
US11807490B2 (en) * | 2019-11-27 | 2023-11-07 | Canon Kabushiki Kaisha | Sheet conveying apparatus and image reading apparatus |
US11518634B2 (en) * | 2021-01-27 | 2022-12-06 | Canon Kabushiki Kaisha | Reading apparatus and image forming system |
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JP2012214294A (en) | 2012-11-08 |
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