Sheet conveyance apparatus, image reading apparatus, and image forming apparatus

Abstract

To provide an image reading apparatus and an image forming apparatus that facilitate settings of a multiple-width stacking mode after skew of documents (bound documents) is detected, thereby improving the operability.SOLUTION: An auto document feeder (ADF) includes: a first sensor 228a configured to detect sheets D1, D2 conveyed from a document tray; a second sensor 228b located adjacent to the first sensor in a width direction orthogonal to sheet conveyance direction to detect the sheets. A control unit of an image reading apparatus is configured to execute stop processing to stop conveyance of the sheets in a case where one of the first sensor and the second sensor does not detect the sheet before a predetermined time period elapses since the sheet is detected by the other of the first sensor and the second sensor. An operation unit of a controller connected to the image reading apparatus via a communication line is configured to display a predetermined screen configured to set a multiple-width stacking mode in which multiple sheets different in width are stacked when the stop processing based on the first sensor and the second sensor is executed.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a sheet conveying device for conveying a sheet, an image reading device for reading an image of the sheet, and an image forming device for forming an image on a recording material.

Background Art

[0002] Conventionally, an image reading device mounted on a copier, a facsimile device, a digital multi-function peripheral, etc. is known to read an image of a document while conveying the document by an automatic document feeder (hereinafter referred to as ADF). Such an ADF separates and feeds a plurality of documents stacked on a document tray one by one. Therefore, the ADF cannot separate and feed a plurality of documents stapled together (referred to as bound documents or staple documents), and if a bound document is erroneously fed, the document may be damaged by the separation operation.

[0003] Therefore, Patent Document 1 discloses an image reading device capable of detecting a bound document by detecting the skew of the document with a plurality of skew detection sensors arranged side by side in the width direction. When a bound document is fed, since the topmost document rotates around the staple, it is possible to determine whether the document is a bound document by detecting the skew of the document.

[0004] In addition, as a function of the ADF, a different-width mixed loading mode (also simply referred to as a mixed loading mode) capable of feeding a plurality of documents with different widths is known. In the different-width mixed loading mode, a document with a small width is placed at a position shifted from the center of conveyance (a position shifted to one side in the width direction). Therefore, when detecting a bound document by the above method in the different-width mixed loading mode, since a document with a small width does not pass through any of the skew detection sensors, it may be erroneously detected as a bound document. Therefore, Patent Document 1 proposes a configuration for notifying that there may be documents with different widths among the set documents when the skew of the document is detected.

Prior Art Documents

Patent Document

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in order for the user to set the mixed-width loading mode after the skew of the manuscript is detected, a plurality of operations are required. For example, after the user cancels the current job, the user needs to enter from the standby screen of the job such as copying to the mode setting screen for function selection, set the mixed-width loading mode, and then return to the standby screen again. Thus, for the user, the operation for setting the mixed-width loading mode after the skew of the manuscript is detected is complicated, and there is a problem that the operability deteriorates.

[0007] Therefore, an object of the present invention is to provide an image reading apparatus and an image forming apparatus that facilitate setting of the mixed-width loading mode after the skew of the manuscript (bound manuscript) is detected and improve the operability.

Means for Solving the Problems

[0008] One aspect of the present invention includes a loading section on which sheets are loaded, a feeding means for separating and feeding the sheets loaded on the loading section one by one, a first sensor for detecting the sheets fed by the feeding means, a second sensor arranged side by side with the first sensor in a width direction orthogonal to the feeding direction of the sheets and for detecting the sheets fed by the feeding means, a control means for executing a stop process for stopping the feeding by the feeding means when the other of the first sensor and the second sensor does not detect a sheet until a predetermined time has elapsed after one of the first sensor and the second sensor detects a sheet, and a display section for displaying a predetermined screen on which a different-width mixed loading mode in which a plurality of sheets having different widths are loaded on the loading section can be set when the stop process based on the first sensor and the second sensor is executed.

[0009] Another aspect of the present invention includes a loading section on which sheets are loaded, a feeding means for separating and feeding the sheets loaded on the loading section one by one, a first sensor for detecting the sheets fed by the feeding means, a second sensor arranged side by side with the first sensor in a width direction orthogonal to the feeding direction of the sheets and for detecting the sheets fed by the feeding means, a control means for determining based on the first sensor and the second sensor whether the sheet fed by the feeding means is skewed, and a display section for displaying a predetermined screen on which a different-width mixed loading mode in which a plurality of sheets having different widths are loaded on the loading section can be set when the control means determines that the sheet fed by the feeding means is skewed.

[0010] Another aspect of the present invention is a sheet conveying apparatus including a loading unit on which sheets are loaded, a feeding unit that separates and feeds the sheets loaded on the loading unit one by one, a first sensor that detects the sheets fed by the feeding unit, a second sensor that is arranged side by side with the first sensor in a width direction orthogonal to the sheet feeding direction and detects the sheets fed by the feeding unit, a control unit that determines whether the sheets fed by the feeding unit are stapled based on the first sensor and the second sensor, and a display unit that displays a predetermined screen on which a mixed-width loading mode in which a plurality of sheets having different widths are loaded on the loading unit can be set when the control unit determines that the sheets fed by the feeding unit are stapled.

Advantages of the Invention

[0011] An object of the present invention is to provide an image reading apparatus and an image forming apparatus that facilitate setting of a mixed-width loading mode after detecting skew of a document (stapled document) and improve operability.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Mode for Carrying Out the Invention

[0013] Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.

[0014] <Image forming apparatus> Referring to FIG. 1, the printer 1001 as an image forming apparatus will be described. FIG. 1 is a cross-sectional view of the printer 1001. In the following description, the position facing the operation unit 506 where the user performs various inputs / settings on the printer 1001 is defined as the "front side" of the printer 1001, and the back side is defined as the "rear side". That is, FIG. 1 shows the internal configuration of the printer 1001 as seen from the front side.

[0015] Printer 1001 includes a printer main body 1001A and an image reading device 1005 disposed above the printer main body 1001A. The operation unit 506 includes a touch panel and functions as a display unit that receives instructions from the user and displays information to the user. The image reading device 1005 includes a scanner unit 100 and an ADF 200 (automatic document feeder). The scanner unit 100 optically scans a document D conveyed by the ADF 200 to read an image of the document D. The document D conveyed by the ADF 200 is a sheet such as plain paper or thin paper, for example. The image data converted into an electrical signal by the image reading device 1005 is transferred to a controller 500 provided in the printer main body 1001A (image forming apparatus main body) via a control unit 160. Printer 1001 can execute a copy mode in which an image is formed on a sheet P (recording medium) based on the image information read by the image reading device 1005, and a scan mode in which the image data read by the image reading device 1005 is transmitted to an external device.

[0016] The printer main body 1001A includes an image forming unit 1033 that forms an image on the sheet P and a sheet feeding unit 1006 that feeds the sheet P to the image forming unit 1033. The sheet feeding unit 1006 includes sheet storage units 1037a, 1037b, 1037c, and 1037d that can store sheets of different sizes. The sheets P stored in the sheet storage units 1037a, 1037b, 1037c, and 1037d are fed out by pickup rollers 1002a, 1002b, 1002c, and 1002d. The sheet P is separated one by one by feed rollers 1003a, 1003b, 1003c, and 1003d and retard rollers 1004a, 1004b, 1004c, and 1004d and fed to a pair of conveyance rollers 1031. The sheet P is conveyed to a pair of registration rollers 1036 by a plurality of pairs of conveyance rollers 1031 arranged along a sheet conveyance path 1007.

[0017] A manual feed tray 1037e is arranged on the side of the printer main body 1001A. A sheet P placed on the manual feed tray 1037e by the user is fed into the printer main body 1001A by a feed roller 1038 and conveyed to a registration roller pair 1036. The leading edge of the sheet P abuts against the nip portion of the stationary registration roller pair 1036, and the skew of the sheet P is corrected. The registration roller pair 1036 starts rotating in accordance with the progress of the toner image forming operation by the image forming unit 1033, and conveys the sheet P to the image forming unit 1033.

[0018] The image forming unit 1033 forms a toner image on the sheet P using an electrophotographic method. The image forming unit 1033 includes a photosensitive drum 1021 which is a photoreceptor. The photosensitive drum 1021 is rotatable along the conveyance direction of the sheet P. Around the photosensitive drum 1021, a charger 1018, an exposure device 1023, a developing device 1024, a transfer charger 1025, a separation charger 1026 and a cleaner 1027 are arranged. The charger 1018 uniformly charges the surface of the rotating photosensitive drum 1021. The exposure device 1023 exposes the photosensitive drum 1021 based on image data input from the image reading device 1005 or an external device (for example, a personal computer), and forms an electrostatic latent image on the photosensitive drum 1021.

[0019] The developing device 1024 accommodates a two-component developer containing toner and a carrier, and develops the electrostatic latent image on the photosensitive drum 1021 into a toner image by supplying charged toner to the photosensitive drum 1021. The toner image formed on the photosensitive drum 1021 is transferred onto the sheet P conveyed by the registration roller pair 1036 by the bias electric field formed by the transfer charger 1025. The sheet P onto which the toner image has been transferred is separated from the photosensitive drum 1021 by the bias electric field formed by the separation charger 1026, and is conveyed toward the fixing unit 1029 by the pre-fixing conveyance unit 1028. The toner remaining on the photosensitive drum 1021 without being transferred to the sheet P is removed by the cleaner 1027.

[0020] The sheet P conveyed to the fixing unit 1029 is heated while being sandwiched and pressed by a pair of rollers, the toner melts and adheres to the sheet P, and an image is fixed on the sheet P. In the case of single-sided printing, the sheet P with an image formed on its surface is discharged by the discharge roller pair 1010 to a discharge tray 1030 that protrudes outside the printer main body 1001A. In the case of double-sided printing, the sheet P with an image formed on its surface has its front and back surfaces reversed by the reversing unit 1039 and is conveyed by the double-sided conveyance unit 1040 to the registration roller pair 1036. The image forming unit 1033 forms a toner image on the back surface (second surface) of the sheet P opposite to the front surface (first surface) of the sheet P. The sheet P with a toner image formed on its back surface is heated and pressed by the fixing unit 1029, and an image is formed on the back surface of the sheet P. The sheet P with images formed on both sides is discharged by the discharge roller pair 1010 to the discharge tray 1030.

[0021] The image forming unit 1033 in the present embodiment forms an image on the sheet P using the electrophotographic method, but the image forming unit 1033 is an example of an image forming means. The image forming unit 1033 may form an image on the sheet P using an inkjet method, an offset printing method, or other methods.

[0022] <Image Reading Device> FIG. 2 is a cross-sectional view of the image reading apparatus 1005. The scanner unit 100 includes a surface reading unit 101 (reading means), a surface flow-through glass 106, a white reference member 108, a document table glass 109, a reading movement guide 110, a timing belt 151, and a document table motor 169. The image reading apparatus 1005 is capable of executing a document fixed reading mode for reading an image of a document placed on the document table glass 109 and a document flow-through reading mode for reading an image of a document conveyed by the ADF 200. In the case of the document fixed reading mode, the scanner unit 100 drives the document table motor 169 and moves the surface reading unit 101 along the reading movement guide 110 by the timing belt 151. The surface reading unit 101 reads the image of the surface of the document placed on the document table glass 109 line by line while moving along the reading movement guide 110 to read the document image. The ADF 200 is rotatable with respect to the scanner unit 100 by a hinge (not shown) and functions as a pressing unit for pressing the document placed on the document table glass 109. In the case of the document flow-through reading mode, the surface reading unit 101 is located at the surface reading position 107 and reads the image of the document conveyed on the surface flow-through glass 106 by the ADF 200. The surface reading unit 101 includes, for example, a contact image sensor (CIS).

[0023] The ADF200, which is a sheet conveyance device, has a document tray 201 and a pair of side regulating plates 202 (a pair of regulating members). The document tray 201 is a stacking portion on which a stack of documents composed of one or more documents is loaded. The document sensor 17 detects the documents loaded on the document tray 201. The pair of side regulating plates 202 are provided on the document tray 201 so as to be movable in the width direction (main scanning direction) orthogonal to the document feeding direction CD, and regulate the movement of the documents in the width direction. Further, the ADF200 has a pickup roller 210 and a separation roller 211. When the ADF200 receives an instruction to start conveying a document, it lowers the pickup roller 210 onto the uppermost surface of the stack of documents loaded on the document tray 201 and rotates it, thereby conveying the uppermost document in the stack of documents. The documents conveyed by the pickup roller 210 are separated and conveyed one by one by the action of the separation roller 211 as a separation mechanism. The separation of the documents by the separation roller 211 is realized by a known separation technique. The pickup roller 210 and the separation roller 211 in the present embodiment are an example of a feeding means for separating and feeding documents one by one.

[0024] When the document separated by the separation roller 211 turns on the separation sensor 212, the counting of the timer 171 (see FIG. 3) starts. The count value of the timer 171 is used to calculate the double-feed detection start timing of the double-feed sensor 213 and to calculate the length of the document. A skew detection unit 228 is arranged downstream of the separation roller 211, and the skew of the document is detected by the skew detection unit 228. Details of the skew detection unit 228 will be described later. When the document reaches the vicinity of the double-feed sensor 213, the double-feed detection by the double-feed sensor 213 starts. Thereafter, the document is conveyed to the registration roller 215. The registration sensor 214 detects that the document has reached the registration roller 215. The leading end of the document is abutted against the nip of the stopped registration roller 215, and the document is bent in a loop shape to correct the skew of the document. Thereafter, the registration roller 215 starts rotating and conveys the document.

[0025] The original document is conveyed from the registration roller 215 to the surface feed glass 106 through the document conveyance path 240 curved in a U shape. When the document conveyed through the document conveyance path 240 turns on the lead sensor 216, the timer 171 is triggered to set the first timer value until the leading edge of the document reaches the surface reading position 107. In the case of double-sided simultaneous reading, the timer 171 is also set with the second timer value until the leading edge of the document reaches the back surface reading position 220. Thereafter, the document is conveyed to the surface reading position 107 by the first lead roller 217. The separation roller 211, the registration roller 215, the document conveyance path 240, and the first lead roller 217 are covered by the exterior ADF cover 204.

[0026] When the timer 171 finishes counting the first timer value for reading the image on the front surface of the document, the reading of the image on the front surface of the document by the front surface reading unit 101 is started. Specifically, the document conveyed on the surface feed glass 106 is irradiated from below the surface feed glass 106 by the surface LED 102 in the front surface reading unit 101. The reflected light from the front surface of the document is read by the surface line sensor 103 (CIS) through the surface lens array 104. Thereby, the image on the front surface of the document is read. While the image on the front surface of the document is being read by the front surface reading unit 101, the document is conveyed from the surface reading position 107 to the back surface reading position 220 by the second lead roller 219.

[0027] When the timer 171 finishes counting the second timer value for reading the image on the back side of the document, the reading of the image on the back side of the document by the back side reading unit 230 (reading means) is started. In the case of double-sided reading, the document conveyed on the back side white facing member provided integrally with the back side flow-through reading glass 234 is irradiated from above the back side flow-through reading glass 234 by the back side LED 231 in the back side reading unit 230. The reflected light from the back side of the document is read by the back side line sensor 232 (CIS) through the back side lens array 233. Thereby, the image on the back side of the document is read. The document is conveyed from the back side reading position 220 to the discharge roller 223 by the third lead roller 221 while the image on the back side of the document is being read by the back side reading unit 230. The discharge sensor 222 detects the document that has reached the third lead roller 221. The document is discharged to the discharge tray 225 through the discharge port 224 by the discharge roller 223.

[0028] As shown in FIG. 2, the front side reading unit 101 and the back side reading unit 230 each include a front side line sensor 103 (CIS) and a back side line sensor 232 (CIS). However, the front side reading unit 101 and the back side reading unit 230 may use a CCD configured with a reduction optical system using a mirror instead of the CIS.

[0029] <Control Configuration> Figure 3 is a block diagram of the image reading apparatus 1005 and the controller 500. The image reading apparatus 1005 includes a control unit 160, a surface LED 102, a surface line sensor 103, a back LED 231, a back line sensor 232, a platen motor 169, and a document conveyance motor 170 that are electrically connected to the control unit 160. The control unit 160 as a control means includes a CPU 164 that is a central processing unit, a ROM 165 that is a read only memory, and a RAM 166 that is a random access memory. The ROM 165 stores a control program for realizing document reading. The RAM 166 stores input data and working data. The control unit 160 further includes a lighting control unit 167, a scanning control unit 168, a timer 171, a front image reading control unit 172, a back image reading control unit 173, a conveyance detection unit 174, an A / D conversion unit 161, and an image processing unit 162. The control unit 160 further includes a document main scanning size acquisition unit 163, a nonvolatile memory 257, and an image processing unit 275.

[0030] The lighting control unit 167 performs on / off control of the illumination of the surface LED 102 and the back LED 231. The scanning control unit 168 performs drive control of the platen motor 169. The platen motor 169 is connected to the front reading unit 101 via a timing belt 151. By the rotation of the platen motor 169, the front reading unit 101 can move in the sub-scanning direction SS along the reading movement guide 110. The scanning control unit 168 performs drive control of the document conveyance motor 170 built in the ADF 200. The document conveyance motor 170 rotates a pick-up roller 210, a separation roller 211, a registration roller 215, a first feed roller 217, a second feed roller 219, a third feed roller 221, and a discharge roller 223 to convey the document.

[0031] The surface line sensor 103 is built into the surface reading unit 101. The surface line sensor 103 receives the reflected light from the document irradiated by the surface LED 102. The amount of light (analog data) received by the surface line sensor 103 is converted into digital data by the A / D conversion unit 161. The image processing unit 162 performs image processing on the digital data from the A / D conversion unit 161 to generate image data. The backside line sensor 232 is built into the backside reading unit 230. The backside line sensor 232 receives the reflected light from the document irradiated by the backside LED 231. The amount of light (analog data) received by the backside line sensor 232 is similarly converted into image data by the A / D conversion unit 161 and the image processing unit 162.

[0032] The document main scanning size acquisition unit 163 as the size information acquisition means acquires the size information input from the operation unit 506 provided in the printer main body 1001A to the CPU 164 via the controller 500. The document main scanning size acquisition unit 163 can also acquire the size information of the document based on the size detection sensor 205 arranged on the document tray 201.

[0033] The image processing unit 275 has a shading RAM 254 and a shading correction circuit 253. The shading RAM 254 has an arithmetic memory 255 and a coefficient memory 256. The CPU 164 can access the shading RAM 254 to read data from the shading RAM 254 or write data to the shading RAM 254.

[0034] The non-volatile memory 257 is a memory (storage unit) that can hold values (data) even when the power of the image reading device 1005 is turned off. The non-volatile memory 257 holds, for example, the shading target value used by the shading correction circuit 253 to perform shading correction, and values such as alarm and error information generated during a job.

[0035] Timer 171 counts the pulse signals transmitted from the document conveyance motor 170. The pulse signals are transmitted from the document conveyance motor 170 each time the document is conveyed by a predetermined distance by the document conveyance motor 170. When the number of pulse signals counted by the timer 171 reaches a preset count value, the timer 171 transmits a count completion signal to the CPU 164. By receiving the count completion signal from the timer 171, the CPU 164 can measure the distance the document has advanced.

[0036] The front surface image reading control unit 172 controls the front surface reading unit 101 to execute the image reading process of the front surface of the document. When the timer 171 completes counting the first timer value set in the timer 171, the timer 171 outputs a first count completion signal to the CPU 164. When the CPU 164 receives the first count completion signal, the CPU 164 transmits a trigger signal to the front surface image reading control unit 172. When the front surface image reading control unit 172 receives the trigger signal, the front surface image reading control unit 172 starts acquiring the document image by the front surface reading unit 101. The back surface image reading control unit 173 controls the back surface reading unit 230 to execute the image reading process of the back surface of the document. When the timer 171 completes counting the second timer value set in the timer 171, the timer 171 outputs a second count completion signal to the CPU 164. When the CPU 164 receives the second count completion signal, the CPU 164 transmits a trigger signal to the back surface image reading control unit 173. When the back surface image reading control unit 173 receives the trigger signal, the back surface image reading control unit 173 starts acquiring the document image by the back surface reading unit 230.

[0037] The conveyance detection unit 174 acquires the ON / OFF states of the separation sensor 212, the skew detection unit 228, the double feed sensor 213, the registration sensor 214, the lead sensor 216, and the discharge sensor 222 provided in the document conveyance path 240. Signals from each sensor are transmitted to the conveyance detection unit 174 when the leading edge of the document reaches each sensor and when the trailing edge of the document passes out of each sensor. By the CPU 164 receiving the signals received by the conveyance detection unit 174 from each sensor as an interrupt, the CPU 164 outputs an instruction signal to the timer 171 without delay.

[0038] The control unit 160 provided in the image reading device 1005 is electrically connected to the controller 500 provided in the printer main body 1001A via the communication line 180. The controller 500 converts the image data read by the image reading device 1005 into image data in a format that can be output to the printer 1001 that forms an image on a sheet (recording medium). The controller 500 also converts the image data read by the image reading device 1005 into image data in a format that can be output to a personal computer (PC). The controller 500 is also in charge of receiving user operations and overall management of the printer 1001. The controller 500 transmits and receives various data signals to and from the control unit 160 of the image reading device 1005 via the communication line 180.

[0039] The controller 500 includes a CPU 501 which is a central processing unit, a ROM 502 which is a read-only memory, and a RAM 503 which is a random access memory. The ROM 502 stores a control program for realizing image conversion and overall management of the printer 1001. Input data and working data are stored in the RAM 503.

[0040] The controller 500 further includes an image processing unit 504 and an image memory 505. The image processing unit 504 converts the image data read by the image reading device 1005 into image data in a format that can be output to the printer 1001. The image memory 505 temporarily stores those image data. The CPU 501 of the controller 500 is electrically connected to the operation unit 506. The operation unit 506 is provided with a display unit and buttons. The CPU 501 receives button operations from the operation unit 506 by the user. The CPU 501 outputs various information to the user to the display unit of the operation unit 506.

[0041] In this embodiment, the image reading apparatus 1005 includes a CPU 164, a ROM 165, and a RAM 166, and the controller 500 also includes a CPU 501, a ROM 502, and a RAM 503. However, for example, the image reading apparatus 1005 may share the CPU 501, the ROM 502, and the RAM 503 of the controller 500 without including the CPU 164, the ROM 165, and the RAM 166. In that case, various components electrically connected to the CPU 164 in FIG. 3 may be directly connected to the CPU 501 of the controller 500 without passing through the communication line 180. In this embodiment, a configuration in which the CPU 164 and the CPU 501 are provided in the image reading apparatus 1005 and the controller 500, respectively, will be described. However, a configuration in which the CPU 164 is omitted and the CPU 501 is shared can be realized by appropriately substituting the description.

[0042] <Staple Detection> As described above, the ADF 200 separates and conveys the originals one by one by the action of the separation roller 211. Therefore, the ADF 200 cannot separate and feed so-called "stapled originals" such as originals stapled together or glued originals. If such an original is accidentally placed on the original tray 201, there is a risk that the original will be damaged by the separation operation of the separation roller 211. Therefore, in this embodiment, the skew detection unit 228 provided in the ADF 200 detects the skew of the original, and stops the feeding operation when the skew of the original is detected, thereby preventing damage to the original. Note that the staple in this embodiment is, for example, a U-shaped needle that can be deformed through a plurality of originals.

[0043] FIG. 5 is a side view and a top view showing the vicinity of the separation roller 211 when the bound document DS is fed. The bound document DS is a bundle of documents stapled by staples at the leading end and the front end of the document. The skew detection unit 228 is composed of a first sensor 228a and a second sensor 228b. The first sensor 228a and the second sensor 228b are arranged downstream of the separation roller 211 and upstream of the registration roller 215 in the feeding direction CD, and are photosensors capable of detecting the leading end of the document, respectively. The first sensor 228a and the second sensor 228b are arranged side by side in the width direction with an interval W therebetween. That is, the first sensor 228a and the second sensor 228b are at the same position in the feeding direction CD and are arranged at different positions in the width direction. More precisely, the first sensor 228a and the second sensor 228b are arranged symmetrically about the center in the width direction (conveying center) of the conveyance path of the ADF 200. However, the first sensor 228a and the second sensor 228b do not necessarily have to be arranged symmetrically about the conveyance center, and may be arranged offset in the feeding direction CD.

[0044] When the first sensor 228a and the second sensor 228b are arranged in this way, when the original document is being conveyed normally (without skewing), they detect the leading edge of the original document almost simultaneously. However, when the stapled original document DS is being conveyed, since the topmost original document cannot be separated, the topmost original document rotates (skews) around the staple portion ST at the separation nip of the separation roller 211. In such a case, as shown in FIG. 5, the second sensor 228b detects the leading edge of the original document earlier than the first sensor 228a. Therefore, if the first sensor 228a does not detect the original document until a predetermined time has elapsed after the second sensor 228b detects the original document, the CPU 164 determines that the fed original document is a stapled original document (there is a possibility that it is a stapled original document). When the staple portion ST of the stapled original document DS is at the rear end, the first sensor 228a detects the leading edge of the original document earlier than the second sensor 228b. Similarly in this case, if the second sensor 228b does not detect the original document until a predetermined time has elapsed after the first sensor 228a detects the original document, the CPU 164 determines that the fed original document is a stapled original document (there is a possibility that it is a stapled original document). That is, when the other does not detect the original document until a predetermined time has elapsed after one of the first sensor 228a and the second sensor 228b detects the original document, the CPU 164 determines that the original document is a stapled original document and executes a stop process to stop the feeding. In this way, from the difference in the detection timings of the first sensor 228a and the second sensor 228b, the CPU 164 can determine whether or not skewing of the original document has occurred (whether or not it is a stapled original document).

[0045] When the CPU 164 stops feeding the document based on the skew detection unit 228, the predetermined time can be arbitrarily set. In the present embodiment, when the leading edge of the document is inclined by 3° with respect to the width direction, the difference in detection timings between the first sensor 228a and the second sensor 228b is used as the predetermined time. Also, in order to detect the skew of the document, it is desirable that the distance W between the first sensor 228a and the second sensor 228b be large. This is because when the distance W is larger, the difference in detection timings between the first sensor 228a and the second sensor 228b becomes more prominent, making it possible to accurately detect the skew of the document. On the other hand, if the distance W is too large, it becomes impossible to detect small-sized documents. Therefore, in the present embodiment, the first sensor 228a and the second sensor 228b are arranged at positions near both ends in the width direction of the smallest-sized document that the ADF 200 can convey.

[0046] <Mixed Loading Mode for Different Widths> FIG. 4(a) is a top view of the ADF 200 with only the same-sized document D1 set on the document tray 201. FIG. 4(b) is a top view of the ADF 200 with the document D1 and the small-sized document D2 set on the document tray 201.

[0047] The pair of side regulating plates 202 is composed of a back-side regulating plate 202a arranged on the back side and a front-side regulating plate 202b arranged on the front side. As shown in FIG. 4(a), the back-side regulating plate 202a abuts against the back-side end of the document, and the front-side regulating plate 202b abuts against the front-side end of the document. The back-side regulating plate 202a and the front-side regulating plate 202b are configured to be interlocked with each other and movable in the width direction by an interlocking mechanism (not shown). For example, when the user moves the front-side regulating plate 202b to the back side, the back-side regulating plate 202a moves to the front side in conjunction with this.

[0048] As shown in Fig. 4(a), when all the manuscripts in the manuscript bundle set on the manuscript tray 201 are of the same size, all the manuscripts D1 abut against both the back regulating plate 202a and the front regulating plate 202b. At this time, the center in the width direction of the manuscript D1 and the conveyance center of the ADF 200 substantially coincide. Thereby, the movement of the manuscript D1 in the width direction is restricted, and the skew of the manuscript during feeding is suppressed. In this embodiment, the mode of feeding a plurality of manuscripts of the same size is called the normal mode or the non-mixed loading mode. Also, when reading a plurality of manuscripts with the same width but different lengths, all the manuscripts abut against both the back regulating plate 202a and the front regulating plate 202b. In this way, the mode of feeding a plurality of manuscripts with the same width but different lengths is called the same-width mixed loading mode.

[0049] On the other hand, there may be a case where the manuscript bundle is composed of a plurality of manuscripts with different widths (in Fig. 4(b), the large manuscript D1 and the small manuscript D2). In this way, the mode of feeding a plurality of manuscripts with different widths is called the different-width mixed loading mode. In the case of the different-width mixed loading mode, the back regulating plate 202a and the front regulating plate 202b are moved in accordance with the large-width manuscript D1. At this time, for the small-width manuscript D2, both end portions in its width direction cannot be regulated by both the back regulating plate 202a and the front regulating plate 202b. Therefore, in the different-width mixed loading mode, the small-width manuscript D2 is placed on the manuscript tray 201 so that only the back end portion abuts against the back regulating plate 202a. At this time, the front end portion of the small-width manuscript D2 does not abut against the front regulating plate 202b. That is, in the different-width mixed loading mode, the small-size manuscript is set on the manuscript tray 201 in a state where it is shifted to the back side. When the user selects the different-width mixed loading mode, a message prompting the user to set the small-size manuscript shifted to the back side is displayed on the operation unit 506 (see Fig. 8(c)).

[0050] FIG. 8 shows the screen displayed on the operation unit 506. FIG. 8(a) is an example of a standby screen in the copy mode. FIG. 8(b) is an example of a setting screen for "other functions". FIG. 8(c) is an example of a setting screen for "mixed original documents". For example, when the user sets the different-width mixed loading mode in the copy mode, the user presses "other functions" 604 in FIG. 8(a), which is the standby screen for copying, on the operation unit 506 to display the screen in FIG. 8(b). Then, the user presses "mixed original documents" 605 on the screen in FIG. 8(b) to display the screen in FIG. 8(c). The screen in FIG. 8(c) is the screen for the user to set the different-width mixed loading mode. Here, the user designates a mode corresponding to the size of the original document bundle placed on the original document tray 201. At this time, when it is a different-width mixed original document, the user presses "different width" 606, and when it is the same-width mixed original document, the user presses "same width" 607. After the user presses "different width" 606 and then presses "OK" 608, the different-width mixed loading mode is set and stored in the RAM 503 as mode information. Then, since the screen of the operation unit 506 returns to FIG. 8(b), the user presses "close" 609 to return to the standby screen in the copy mode in FIG. 8(a). After the user makes other settings and then presses "start" 610, the information stored in the RAM 503 is transmitted to the CPU 164 via the communication line 180, and the image reading device 1005 starts feeding the original document in the different-width mixed loading mode.

[0051] <Control in the Different-Width Mixed Loading Mode> In the mixed loading mode with different widths, the control unit 160 of the present embodiment executes conveyance control different from the normal mode. FIG. 6 is a diagram showing the relationship between the document and the skew detection unit 228 during mixed loading with different widths. In the example of FIG. 6, as in FIG. 4(b), a case where a large document D1 and a small document D2 are mixedly loaded is shown. As described above, in the mixed loading mode with different widths, the small-sized document D2 is set at a position deviated from the conveyance center. Also, as described above, the first sensor 228a and the second sensor 228b of the skew detection unit 228 are arranged side by side in the width direction. Therefore, in the mixed loading mode with different widths, when the small-sized document D2 is fed, the small-sized document D2 may pass only through the first sensor 228a and not through the second sensor 228b. In such a case, since the second sensor 228b does not detect the document D2 until a predetermined time has elapsed after the first sensor 228a detects the document D2, the CPU 164 erroneously detects that skew has occurred (the document is stapled). Therefore, in the present embodiment, in the mixed loading mode with different widths, the control unit 160 invalidates the skew detection (staple detection) by the skew detection unit 228. At this time, the control unit 160 may not perform the detection of the document itself by the first sensor 228a and the second sensor 228b, or may ignore the detection results of the first sensor 228a and the second sensor 228b. In any case, in the mixed loading mode with different widths, the control unit 160 does not stop the feeding based on both the first sensor 228a and the second sensor 228b. Conversely, in the normal mode and the mixed loading mode with the same width, the control unit 160 executes the skew detection by the skew detection unit 228.

[0052] FIG. 10(a) is a diagram showing the image area A and the position of the document when the document interval is small. FIG. 10(b) is a diagram showing the image area A and the position of the document when the document interval is large. In the different-width mixed loading mode, since the small-size document D2 is set at a position deviated from the conveyance center, the pickup roller 210 and the separation roller 211 contact the front side of the center of the small-size document D2. Therefore, in the different-width mixed loading mode, there is a tendency that the skew of the document is more likely to occur than in the normal mode. When the skew is large, for example, when the control unit 160 performs a process of determining the leading edge of the document from the image within a predetermined area (image area A), as shown in FIG. 10(a), the trailing edge of the preceding document and the leading edge of the subsequent document may appear overlapping within the same image area A. Thus, in the different-width mixed loading mode, in the process of detecting the leading edge position, the angle of the document, etc. based on the image data, the risk of misdetection, etc. becomes higher than in the normal mode. Therefore, in the different-width mixed loading mode, the control unit 160 controls the conveyance so that the distance between the trailing edge of the preceding document and the leading edge of the subsequent document (the interval between sheets, intersheet) becomes larger than in the normal mode. As a result, as shown in FIG. 10(b), one document can be contained within one image area A, and stable reading can be realized.

[0053] FIG. 11(a) is a diagram for explaining the white filling process when the white filling start timing is early. FIG. 11(b) is a diagram for explaining the white filling process when the white filling start timing is late. The control unit 160 has a function of white filling the outside of the document area. In such a case, if the white filling is started from the document trailing edge detection timing as shown in FIG. 11(a), a part of the skewed document may be white filled, and there is a possibility of image missing. Therefore, in the different-width mixed loading mode, by delaying the white filling start timing as shown in FIG. 11(b) more than in the normal mode, the risk of image missing can be reduced.

[0054] Also, when the mixed-width loading mode is not specified (i.e., the normal mode), regardless of the size of the read manuscript, the sheet P to be printed is determined based on the size of the manuscript detected on the manuscript tray 201. Here, in the case of a mixed-width manuscript, the size of the largest manuscript in the manuscript bundle is detected on the manuscript tray 201, and the sheet P to be printed is determined based on the size of the manuscript detected here. For example, when two types of manuscripts with A4 size and B5 size are run in the same job in the copy mode, both will be output in A4 size. Therefore, in the present embodiment, in the mixed-width loading mode, the control unit 160 executes printing on an appropriate sheet P for each manuscript based on the size of the read manuscript. As a result, the copy output of the A4-size manuscript is printed on A4 paper, and the copy output of the B5-size manuscript is printed on B5 paper.

[0055] As described above, the control unit 160 executes conveyance control different from the normal mode in the mixed-width loading mode. Therefore, it is desirable for the user to set the normal mode when reading a manuscript bundle of only the same size, and to set the mixed-width loading mode when reading a mixed manuscript. However, in the mixed-width loading mode, the paper to be output by the printer main body 1001A cannot be known until the manuscript size is determined, so the productivity of the job is higher in the normal mode where sheets P of the same size are continuously output. Therefore, it is desirable that the default is a state where the normal mode is selected (the mixed-width loading mode is not set), and when the user reads a mixed-width manuscript, it operates in the mixed-width loading mode.

[0056] <Display content at the time of skew detection> FIG. 7 is an example of a predetermined screen displayed on the operation unit 506 when the skew detection unit 228 detects the skew of the document. The screen in FIG. 7 is displayed on the operation unit 506 simultaneously when the skew of the document is detected and the feeding process is stopped. Note that the timing of displaying the screen in FIG. 7 is not limited to this, and for example, it may be displayed after the user removes the document stopped in the ADF 200. On the screen of FIG. 7, a button 601 for temporarily turning off the skew detection sensor and a button 602 for turning on the mixed loading of documents with different widths (different-width mixed loading mode) are displayed. Here, when the actually fed document is a bound document, the user presses the cancel button 603 to cancel the job. Then, the user removes the documents remaining in the transport path of the ADF 200, including the bound document whose feeding has stopped. After that, the user excludes the bound document or removes staple pins, etc., and then places the document bundle on the document tray 201 again to restart the job.

[0057] If the actually fed document is not a bound document and is a document of the same size, there is a possibility that the document is placed obliquely on the document tray 201 (rough set), or the document is in a state where it is likely to skew due to wrinkles or creases. In the case of rough set, the user can realign the document bundle and place it on the document tray 201 again. However, if the document is in a state where it is likely to skew, if it is transported again, it may be determined as skewed again by the skew detection unit 228, and the transport may be interrupted. Therefore, the user presses the button 601 for temporarily turning off the skew detection sensor. When the button 601 is pressed, information to that effect is stored in the RAM 503. When the transport of the document is restarted in this state, the information in the RAM 503 is transmitted to the CPU 164 via the communication line 180, and the skew detection by the skew detection unit 228 is invalidated. That is, the button 601 is an example of a second setting unit for invalidating the skew detection by the skew detection unit 228 without setting the different-width mixed loading mode for the job (remaining in the normal mode) when restarting the stopped job. As a result, even if the document is in a state where it is likely to skew, the job will not be interrupted, and it becomes possible to read the document bundle.

[0058] Next, a case where the actually fed original is a mixed-width original and the user has not set the mixed-width mode will be described. Cases where the mixed-width mode is not set include cases where the user is unaware of the existence of the mixed-width mode, cases where the user is aware but has forgotten the setting, or cases where an original of a different size has been mixed in with other originals in the stack of originals. In such cases, the user presses the button 602 to turn on the mixed loading of originals of different widths. When the button 602 is pressed, the same information as when the "different width" 606 in Fig. 8(c) is pressed is stored in the RAM 503. That is, the button 602 is an example of a first setting unit for setting the mixed-width mode for the job when restarting the stopped job. When the conveyance of the original is restarted in this state, the information in the RAM 503 is transmitted to the CPU 164 via the communication line 180, and the feeding in the mixed-width mode is executed. As described above, in the mixed-width mode, the CPU 164 invalidates the skew detection by the skew detection unit 228, so that the job is not interrupted and it becomes possible to read the stack of originals.

[0059] Note that the button 602 for turning on the mixed loading of originals of different widths may have a text surface other than that described in Fig. 7. For example, it may be a sentence "Mixing originals of different widths" that prompts the user to approve the setting of the mixed-width mode, or an icon may be displayed as shown above the "different width" 606 in Fig. 8(c) to make it easier to visually recognize.

[0060] <Explanation of the flowchart> Fig. 9 is a flowchart diagram implemented when the feeding of the original is interrupted. The process shown in Fig. 9(a) is implemented by the CPU 164 executing the program stored in the ROM 165. The process shown in Fig. 9(b) is implemented by the CPU 501 executing the program stored in the RAM 503.

[0061] First, when an image reading job is started, the CPU 501 issues a conveyance start command to the image reading device 1005 at S1100 in FIG. 9(b). Then, when the feeding of the document by the ADF 200 is started, the CPU 164 determines at S1001 in FIG. 9(a) whether an instruction to turn off staple detection or an instruction to specify the mixed loading mode with different widths is given. If either instruction is given, the process proceeds to S1008. If neither instruction is given, skew detection by the skew detection unit 228 is performed at S1002. Next, the CPU 164 compares the skew detection results at S1003. If the skew amount of the document is less than the predetermined value, the CPU 164 determines that the document is being fed normally and proceeds to the process of S1008.

[0062] If the skew amount of the document is equal to or greater than the predetermined value at S1003, the process proceeds to the process of S1004. At S1004, the CPU 164 stops the document conveyance motor 170 of the ADF 200 to stop the feeding of the document, and transmits a message indicating that an abnormal stop has occurred to the CPU 501. Then, the process proceeds to the process of S1005, and the CPU 164 enters a state of waiting for the next command from the CPU 501. Here, the CPU 501 determines at S1101 in FIG. 9(b) whether information indicating an abnormal stop has been transmitted. If it is not an abnormal stop, the process proceeds to the process of S1109, but if it is an abnormal stop, the process proceeds to the process of S1102. At S1102, the CPU 501 causes the operation unit 506 to display the screen of FIG. 7 to prompt the user for the next instruction. Then, the process proceeds to the process of S1103, and the CPU 501 determines whether any of the buttons 601 to 603 in FIG. 7 has been pressed. If any of the buttons 601 to 603 has been pressed, the process proceeds to the process of S1104, and the CPU 501 determines the pressed button. If the cancel button 603 is pressed, the CPU 501 ends the process of this flowchart. If the button 601 to turn off the skew detection sensor is pressed, the process proceeds to the process of S1105, stores the information to that effect in the RAM 503, and proceeds to the process of S1106. If the button 602 to turn on the mixed loading mode with different widths is pressed at S1104, the process proceeds to the process of S1205, stores the information to that effect in the RAM 503, and proceeds to the process of S1106.

[0063] In S1106, the CPU 501 waits for the operation to be executed next from the user. If there is an instruction from the user, the process proceeds to S1107, and the CPU 501 determines whether the instruction from the user is a conveyance restart instruction. If the instruction from the user is not a conveyance restart instruction, the CPU 501 ends the processing of this flowchart. If the instruction from the user is a conveyance restart instruction, the process proceeds to S1108, and the CPU 501 transmits the information stored in the RAM 503 in S1105 or S1205 and the manuscript conveyance start command to the CPU 164 via the communication line 180. Then, assuming there is an implementation content instruction in S1005 of FIG. 9(a), the process proceeds to S1006, and the CPU 164 determines whether the instruction from the user is a conveyance restart instruction. If the instruction from the user is not a conveyance restart instruction, the CPU 164 ends the processing of the flowchart in FIG. 9(a). If the instruction from the user is a conveyance restart instruction, the process proceeds to S1007, and the CPU 164 starts manuscript conveyance in the mode instructed by the CPU 501. At this time, the user performs so-called jam processing such as returning the manuscript that was being conveyed previously to the manuscript tray 201 as needed. The CPU 164 determines whether there is no more manuscript in the manuscript tray 201 in S1008. If there is still manuscript, the process returns to S1001. When all the manuscripts have been fed and there is no more manuscript in the manuscript tray 201, the CPU 164 transmits image reading end information to the CPU 501 in S1009 and ends the processing of the flowchart in FIG. 9(a). Then, in S1109 of FIG. 9(b), the CPU 501 determines whether image reading end information has been transmitted from the image reading device. If the image reading end information has not been transmitted, the process returns to S1101, and the CPU 501 continuously monitors the abnormal conveyance of the manuscript until the manuscript conveyance ends. If the image reading end information has been transmitted, the CPU 501 ends the processing of the flowchart in FIG. 9(b).

[0064] As described above, in this embodiment, when the skew of the document is detected and the feeding operation is stopped, the operation unit 506 displays a predetermined screen including a button 602 that can set the different-width mixed loading mode. Thereby, even when the user forgets to set the different-width mixed loading mode or is unaware of the existence of the different-width mixed loading mode, it is possible to resume feeding the document in an appropriate mode. Furthermore, it is possible to simplify the operation for setting the different-width mixed loading mode after the feeding operation has stopped.

[0065] Also, in this embodiment, when the skew of the document is detected and the feeding operation is stopped, the operation unit 506 displays a predetermined screen including a button 601 for invalidating the skew detection by the skew detection unit 228 without setting the different-width mixed loading mode. Thereby, even in a state where the document is likely to skew due to wrinkles or creases, etc., it is possible to resume feeding the document in an appropriate state. Also, when the button 601 is pressed, since the different-width mixed loading mode is not set and the normal mode remains, the job can be resumed without reducing productivity.

[0066] Also, the button 602 for turning on the mixed loading of documents of different widths does not necessarily have to be displayed on the operation unit 506 when the feeding of the document stops. For example, when the feeding of the document stops in a job where the same-width mixed loading mode or the different-width mixed loading mode has already been set, the button 602 for turning on the mixed loading of documents of different widths may be made non-displayed as shown in Fig. 12(a). Similarly, in the case where the same-width mixed loading mode or the different-width mixed loading mode has already been set, the button 602 for turning on the mixed loading of documents of different widths may be grayed out and made unselectable as shown in Fig. 12(b). Thereby, it is possible to prevent the user from performing unnecessary operations and improve the operability.

Explanation of Signs

[0067] 1001 Printer 1001A Printer Main Body 1005 Image Reading Device 100 Scanner Unit 200 ADF 228 Skew Detection Unit 228a First sensor 228b Second sensor 506 Operation unit

Claims

1. A loading section on which sheets are loaded, feeding means for separating and feeding the sheets loaded on the loading section one by one, a first sensor for detecting the sheets fed by the feeding means, a second sensor arranged side by side with the first sensor in the width direction orthogonal to the sheet feeding direction and for detecting the sheets fed by the feeding means, control means for executing a stop process of stopping the feeding by the feeding means when the other of the first sensor and the second sensor does not detect a sheet until a predetermined time has elapsed after one of the first sensor and the second sensor detects a sheet, a display section for displaying a predetermined screen on which a mixed loading mode with different widths in which a plurality of sheets with different widths are loaded on the loading section can be set when the stop process based on the first sensor and the second sensor is executed, comprising a sheet conveying device characterized by the above.

2. In the mixed loading mode with different widths, the control means does not execute the stop process based on the first sensor and the second sensor. The sheet conveying device according to claim 1, characterized by the above.

3. The predetermined screen includes a first setting section for setting the mixed loading mode with different widths and a second setting section for invalidating the stop process based on the first sensor and the second sensor without setting the mixed loading mode with different widths. The sheet conveying device according to claim 2, characterized by the above.

4. When the stop process based on the first sensor and the second sensor is executed in a state where the mixed loading mode with different widths is set, the display section does not display the second setting section. The sheet conveying device according to claim 3, characterized by the above.

5. In the mixed loading mode with different widths, the control means controls the feeding means so that the interval between sheets is larger than when the mixed loading mode with different widths is not set. The sheet conveying device according to claim 1, characterized by the above.

6. A pair of regulating members provided movably in the width direction on the loading section and abutting on both end portions in the width direction of the sheets loaded on the loading section, In the mixed loading mode with different widths, among the plurality of sheets with different widths loaded on the loading section, the sheets with a smaller width are loaded on the loading section so as to abut on the regulating member arranged on the back side among the pair of regulating members. The sheet conveying device according to claim 1, characterized by the above.

7. A loading section on which sheets are loaded, Feeding means for separating and feeding the sheets stacked on the stacking unit one by one; A first sensor for detecting the sheet fed by the feeding means; A second sensor arranged side by side with the first sensor in the width direction orthogonal to the sheet feeding direction and detecting the sheet fed by the feeding means; Control means for determining whether the sheet fed by the feeding means is skewed based on the first sensor and the second sensor; A display unit for displaying a predetermined screen capable of setting a different-width mixed loading mode in which a plurality of sheets with different widths are stacked on the stacking unit when the control means determines that the sheet fed by the feeding means is skewed; Comprising; A sheet conveying device characterized by this.

8. A stacking unit on which sheets are stacked; Feeding means for separating and feeding the sheets stacked on the stacking unit one by one; A first sensor for detecting the sheet fed by the feeding means; A second sensor arranged side by side with the first sensor in the width direction orthogonal to the sheet feeding direction and detecting the sheet fed by the feeding means; Control means for determining whether the sheet fed by the feeding means is stapled based on the first sensor and the second sensor; A display unit for displaying a predetermined screen capable of setting a different-width mixed loading mode in which a plurality of sheets with different widths are stacked on the stacking unit when the control means determines that the sheet fed by the feeding means is stapled; Comprising; A sheet conveying device characterized by this.

9. The sheet conveying device according to any one of claims 1 to 8, and Reading means for reading an image of the sheet fed from the stacking unit by the feeding means; Comprising; An image reading device characterized by this.

10. The image reading device according to claim 9, and Image forming means for forming an image on a recording medium based on the image information of the sheet read by the reading means; Comprising; An image forming device characterized by this.

Images