Image reading device, image formation device, and image reading method

Abstract

To provide an image reading device, an image formation device, and an image reading method, capable of suppressing reading failure of each image of a plurality of scripts of which a size in a width direction is different, that is mounted to a script mounting part.SOLUTION: An image formation device comprises: a detection processing part that detects a position of a first guide member 15A; a limitation processing part that limits an image reading range in the width direction of a script X by the image reading part to a script width corresponded to a detection result by the detection processing part; and an output processing part, in the case of limiting the image reading range to a script width W1 of a letter size by the limitation processing part, reads an image of the script X by using the image reading part, detects a contact end part IM13 contacted to a first guide member 15A in the script X contained in a reading image IM10 to be read, and cuts and outputs a second region AR20 determined on the basis of the contact end part IM13, the size of the script X from the reading image IM10.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an image reading apparatus, an image forming apparatus, and an image reading method.

Background Art

[0002] An image reading apparatus including an ADF (Automatic Document Feeder) for conveying a document is known. This type of image reading apparatus includes a document placement unit, an image reading unit, and a regulating unit. The document is placed on the document placement unit along a predetermined conveyance path. The image reading unit reads an image of the document at a predetermined reading position in the conveyance path. The regulating unit is provided so as to be movable in the width direction orthogonal to the conveyance direction of the document in the document placement unit, and regulates the position of the document in the width direction placed on the document placement unit.

[0003] Also, an image reading apparatus for reading images of a plurality of documents placed on the document placement unit and having different sizes in the width direction from each other is known (see, for example, Patent Document 1). For example, this type of image reading apparatus includes a detection processing unit, a restriction processing unit, a determination processing unit, and an output processing unit. The detection processing unit detects the position of the regulating unit in the document placement unit. The restriction processing unit restricts the image reading range in the width direction by the image reading unit to the document width corresponding to the detection result by the detection processing unit. The determination processing unit determines the size of the document based on the size of the document in the conveyance direction detected from the document conveyed toward the reading position. The output processing unit reads an image of the document passing through the reading position using the image reading unit, and cuts out and outputs a region determined based on a specific end corresponding to the regulating unit among both ends in the width direction of the read image and the determination result by the determination processing unit from the read image. The image reading apparatus having the above-described configuration can read images of a plurality of documents placed on the document placement unit such that each of the plurality of documents having different sizes in the width direction contacts the regulating unit.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the image reading device, when the original document of A4 vertical size or the original document of letter size is placed on the original document placement unit, it may not be possible to identify whether the original document width of the original document placed on the original document placement unit is the original document width of the A4 vertical size original document or the original document width of the letter size original document. In contrast, a configuration is conceivable in which the image reading range by the image reading unit is limited to the original document width of the letter size original document regardless of whether the size of the original document placed on the original document placement unit is A4 vertical size or letter size. In this configuration, when the size of the original document placed on the original document placement unit is letter size, it is possible to read all of the image of the original document. However, in this configuration, when the size of the original document placed on the original document placement unit is A4 vertical size, the original document area in the read image is shifted toward the center side in the width direction in the read image from the specific end portion, so that it is not possible to read all of the image of the A4 vertical size original document.

[0006] An object of the present invention is to provide an image reading device, an image forming device, and an image reading method capable of suppressing reading failure of each image of a plurality of original documents having different widths in the width direction placed on an original document placement unit.

Means for Solving the Problems

[0007] An image reading apparatus according to one aspect of the present invention includes a document placement unit, an image reading unit, a restricting unit, a detection processing unit, a limiting processing unit, a determination processing unit, and an output processing unit. A document to be conveyed along a predetermined conveyance path is placed on the document placement unit. The image reading unit reads an image of the document at a predetermined reading position in the conveyance path. The restricting unit is provided movably in a width direction orthogonal to the conveyance direction of the document in the document placement unit, and restricts the position of the document in the width direction placed on the document placement unit. The detection processing unit detects the position of the restricting unit in the document placement unit. The limiting processing unit restricts the image reading range in the width direction by the image reading unit to the document width corresponding to the detection result by the detection processing unit. The determination processing unit determines the size of the document based on the size of the document in the conveyance direction detected from the document conveyed toward the reading position. The output processing unit, when the image reading range is restricted to a predetermined specific document width by the limiting processing unit, reads an image of the document passing through the reading position using the image reading unit, detects a contact end portion in contact with the restricting unit in the document included in the read image, and executes an output processing of cutting out and outputting a region determined based on the contact end portion and the determination result by the determination processing unit from the read image.

[0008] An image forming apparatus according to another aspect of the present invention includes the image reading apparatus and an image forming unit. The image forming unit forms an image on a sheet based on the image read by the image reading apparatus.

[0009] An image reading method according to another aspect of the present invention includes a document placement unit on which a document to be conveyed along a predetermined conveyance path is placed, an image reading unit that reads an image of the document at a predetermined reading position in the conveyance path, and a regulation unit that is provided so as to be movable in a width direction orthogonal to the conveyance direction of the document in the document placement unit and regulates the position of the document in the width direction placed on the document placement unit. The method is executed by an image reading apparatus and includes a detection step, a restriction step, a determination step, and an output step. In the detection step, the position of the regulation unit in the document placement unit is detected. In the restriction step, the image reading range in the width direction by the image reading unit is restricted to the document width corresponding to the detection result by the detection step. In the determination step, the size of the document is determined based on the size of the document in the conveyance direction detected from the document conveyed toward the reading position. In the output step, when the image reading range is restricted to a predetermined specific document width by the restriction step, an image of the document passing through the reading position is read using the image reading unit, a contact end portion in contact with the regulation unit in the document included in the read image is detected, and an output process of cutting out and outputting a region determined based on the contact end portion and the determination result by the determination step from the read image is executed.

Advantages of the Invention

[0010] According to the present invention, it is possible to suppress reading failures of images of a plurality of documents placed on a document placement unit and having different sizes in the width direction from each other.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

[0012] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the following embodiments are merely examples of embodying the present invention and do not limit the technical scope of the present invention.

[0013] [Configuration of Image Forming Apparatus 100] First, with reference to FIGS. 1 to 3, the configuration of the image forming apparatus 100 according to an embodiment of the present invention will be described. Here, FIG. 1 is a cross-sectional view showing the configuration of the image forming apparatus 100. FIG. 2 is a plan view showing the configuration of the ADF 1.

[0014] The image forming apparatus 100 is a multifunction device having a plurality of functions such as a scan function for reading an image from a document X (see FIG. 1), a print function for forming an image based on image data, a fax function, and a copy function. Note that the image forming apparatus 100 may be a copy machine.

[0015] As shown in FIGS. 1 and 3, the image forming apparatus 100 includes an ADF (auto document feeder) 1, an image reading unit 2, an image forming unit 3, a paper feeding unit 4, an operation display unit 5, a storage unit 6, and a control unit 7.

[0016] The image forming unit 3 forms an image on a sheet based on image data. Specifically, the image forming unit 3 forms an image on the sheet by an electrophotographic method. For example, the image forming unit 3 includes a photosensitive drum, a charging roller, an optical scanning device, a developing device, a transfer roller, a cleaning device, a fixing device, and a paper discharge tray. Note that the image forming unit 3 may form an image on the sheet by another image forming method such as an inkjet method.

[0017] The paper feeding unit 4 supplies a sheet to the image forming unit 3. The paper feeding unit 4 includes a paper feed cassette and a plurality of conveying rollers.

[0018] The operation display unit 5 is a user interface of the image forming apparatus 100. The operation display unit 5 includes a display unit and an operation unit. The display unit displays various information in response to a control instruction from the control unit 7. For example, the display unit is a liquid crystal display. The operation unit inputs various information to the control unit 7 in response to a user's operation. For example, the operation unit is a touch panel.

[0019] The storage unit 6 is a non-volatile storage device. For example, the storage unit 6 is a non-volatile memory such as a flash memory. Note that the storage unit 6 may be an SSD (Solid State Drive) or an HDD (Hard Disk Drive).

[0020] The control unit 7 comprehensively controls the image forming apparatus 100. As shown in FIG. 3, the control unit 7 includes a CPU 7A, a ROM 7B, and a RAM 7C. The CPU 7A is a processor that executes various arithmetic processes. The ROM 7B is a non-volatile storage device in which information such as control programs for causing the CPU 7A to execute various processes is stored in advance. The RAM 7C is a volatile or non-volatile storage device used as a temporary storage memory (working area) for various processes executed by the CPU 7A. In the control unit 7, various control programs stored in advance in the ROM 7B are executed by the CPU 7A. Thereby, the control unit 7 comprehensively controls the image forming apparatus 100. Note that the control unit 7 may be configured by an electronic circuit such as an integrated circuit (ASIC). Further, the control unit 7 may be a control unit provided separately from the main control unit that comprehensively controls the image forming apparatus 100.

[0021] The ADF 1 conveys the document X on which an image is read by the image reading unit 2. As shown in FIG. 1, the ADF 1 includes a document tray 11, a plurality of conveyance rollers 12, a document guide 13, and a paper discharge unit 14.

[0022] On the document tray 11, the document X to be conveyed along a predetermined conveyance path R1 (see FIG. 1) is placed. The conveyance path R1 is a path that extends from the document tray 11 through the inside of the housing of the ADF 1 to the paper discharge unit 14. The plurality of conveyance rollers 12 are arranged side by side along the conveyance path R1. Each of the conveyance rollers 12 is driven by a driving force supplied from a motor (not shown). Thereby, the document X placed on the document tray 11 is conveyed along the conveyance path R1. The document guide 13 is provided on the conveyance path R1 and guides the document X conveyed along the conveyance path R1 to the image reading position by the image reading unit 2. The reading position is the upper surface of the second contact glass 212 (see FIG. 1) of the document table 21. The paper discharge unit 14 discharges the document X after the image has been read. The document tray 11 is an example of the document placement unit of the present invention.

[0023] The image reading unit 2 reads the image of the document X at the reading position. Also, the image reading unit 2 reads the image of the document X placed on the first contact glass 211 (see FIG. 1) of the document table 21. Specifically, the image reading unit 2 reads the image of the document X by a CCD (Charge Coupled Device) method. As shown in FIG. 1, the image reading unit 2 includes a document table 21, a reading unit 22, a mirror 23, a mirror 24, an optical lens 25, and a CCD 26.

[0024] The document table 21 is the upper surface portion of a box-shaped housing that houses each component of the image reading unit 2. As shown in FIG. 1, the document table 21 includes a first contact glass 211 and a second contact glass 212. The document X is placed on the upper surface of the first contact glass 211. The second contact glass 212 transmits the light emitted from the reading unit 22 toward the document X conveyed by the ADF 1.

[0025] As shown in FIG. 1, an ADF 1 is provided above the document table 21. The ADF 1 is provided so as to be able to change its posture between a closed posture covering the first contact glass 211 and an open posture exposing the first contact glass 211. Thereby, the ADF 1 functions as a document cover for the document X placed on the first contact glass 211.

[0026] As shown in FIG. 1, the reading unit 22 is provided below the first contact glass 211 and the second contact glass 212. The reading unit 22 is configured to be movable in the sub-scanning direction D2 shown in FIG. 1 by a moving mechanism (not shown) having a driving unit such as a stepping motor. As shown in FIG. 1, the reading unit 22 includes a light source 221 and a mirror 222.

[0027] The light source 221 is a plurality of LEDs arranged along the main scanning direction D1 (see FIG. 2). The main scanning direction D1 is a direction orthogonal to the sub-scanning direction D2. The light source 221 irradiates light for one line in the main scanning direction D1 toward the first contact glass 211 or the second contact glass 212. The light emitted from the light source 221 passes through the first contact glass 211 or the second contact glass 212 and irradiates the document X placed on the first contact glass 211 or the document X conveyed by the ADF1. The mirror 222 reflects the light emitted from the light source 221 and reflected by the document X to the mirror 23.

[0028] In the image reading unit 2, when an image is read from the document X placed on the first contact glass 211, the reading unit 22 is moved in the sub-scanning direction D2 by the moving mechanism. Thereby, the light irradiated from the light source 221 to the document X is scanned in the sub-scanning direction D2. Also, in the image reading unit 2, when an image is read from the document X conveyed by the ADF1, the reading unit 22 is moved by the moving mechanism to a position below the second contact glass 212. Thereby, the light emitted from the light source 221 passes through the second contact glass 212 and irradiates the document X conveyed by the ADF1.

[0029] The mirror 23 reflects the light reflected by the mirror 222 of the reading unit 22 to the mirror 24. The mirror 24 reflects the light reflected by the mirror 23 to the optical lens 25. The optical lens 25 condenses the light reflected by the mirror 24 and makes it incident on the CCD 26.

[0030] CCD26 is an image sensor having a plurality of photoelectric conversion elements arranged along the main scanning direction D1. CCD26 outputs an electrical signal corresponding to the amount of light received. In the image reading unit 2, the light emitted from the light source 221 and reflected by the document X is incident on the CCD26 via the mirror 222, the mirror 23, the mirror 24, and the optical lens 25. As a result, an analog electrical signal corresponding to the image of the document X is output from the CCD26. The analog electrical signal output from the CCD26 is converted into a digital electrical signal (image data) by an AFE (analog front end) circuit (not shown) and input to the control unit 7. The image data output from the image reading unit 2 is used for forming an image by the image forming unit 3 and the like.

[0031] As shown in FIGS. 2 and 3, the ADF1 includes a document regulating unit 15, a signal output circuit 16, and a sensor 17.

[0032] The document regulating unit 15 regulates the position of the document X placed on the document tray 11 in the width direction. The width direction is a direction orthogonal to the conveyance direction D3 (see FIG. 2) of the document X by the ADF1 and is the same direction as the main scanning direction D1. As shown in FIG. 2, the document regulating unit 15 includes a first guide member 15A, a second guide member 15B, a first rack 15C, a second rack 15D, and a pinion 15E.

[0033] The first guide member 15A is provided movably in the width direction on the document tray 11 and regulates the position of the document X placed on the document tray 11 in the width direction. The first guide member 15A is a flat plate-shaped member that is long in the conveyance direction D3 and has a thickness in the width direction.

[0034] The second guide member 15B is provided movably in the width direction on the document tray 11 and regulates the position of the document X placed on the document tray 11 in the width direction. The second guide member 15B is a flat plate-shaped member that is long in the conveyance direction D3 and has a thickness in the width direction, similar to the first guide member 15A. The second guide member 15B is provided opposite to the first guide member 15A in the width direction.

[0035] The first rack 15C is provided so as to be movable integrally with the first guide member 15A. The first rack 15C is provided below the upper surface of the document tray 11. The first rack 15C is long in the width direction, and teeth are formed on the side surface on the upstream side in the conveyance direction D3.

[0036] The second rack 15D is provided so as to be movable integrally with the second guide member 15B. The second rack 15D is provided below the upper surface of the document tray 11. The second rack 15D is long in the width direction, and teeth are formed on the side surface on the downstream side in the conveyance direction D3.

[0037] The pinion 15E is provided between the first rack 15C and the second rack 15D and meshes with both the first rack 15C and the second rack 15D. The pinion 15E is supported rotatably about an axis orthogonal to the upper surface below the upper surface of the document tray 11.

[0038] In the document regulating unit 15, the first guide member 15A and the second guide member 15B are interlocked in a direction approaching or separating from each other in the width direction by the first rack 15C, the second rack 15D, and the pinion 15E. Thereby, the document regulating unit 15 can position the document X placed on the document tray 11 at the center in the width direction in the document tray 11. Note that, in the document tray 11, only the first guide member 15A of the first guide member 15A and the second guide member 15B may be provided movably, and the other may be provided immovably. The first guide member 15A is an example of the regulating unit of the present invention.

[0039] The signal output circuit 16 outputs an electrical signal corresponding to the position of the first guide member 15A in the document tray 11. In other words, the signal output circuit 16 outputs an electrical signal corresponding to the separation distance between the first guide member 15A and the second guide member 15B in the width direction. For example, the signal output circuit 16 is an electronic circuit including a variable resistor whose electrical resistance value changes according to the rotation of the pinion 15E. The signal output circuit 16 outputs an electrical signal corresponding to the electrical resistance value of the variable resistor. The electrical signal output from the signal output circuit 16 is input to the control unit 7.

[0040] The sensor 17 is used to detect the size in the conveyance direction D3 of the document X conveyed toward the reading position. For example, the sensor 17 is a reflection type or transmission type optical sensor capable of detecting the document X upstream of the reading position in the conveyance direction D3 in the conveyance path R1.

[0041] The image forming apparatus 100 is capable of reading images of a plurality of documents X each having a different document width in the document tray 11 when the plurality of documents X are placed so that each contacts the first guide member 15A.

[0042] [Configuration of Control Unit 7] Next, the configuration of the control unit 7 will be described with reference to FIGS. 3 and 4. In FIG. 4, hatching is applied to the document area IM11 included in the read image IM10. Also, in FIG. 4, the first area AR10 cut out from the read image IM10 is indicated by a thick line.

[0043] As shown in FIG. 3, the control unit 7 includes a detection processing unit 31, a restriction processing unit 32, a determination processing unit 33, and an output processing unit 34. An apparatus including the ADF 1, the image reading unit 2, and the control unit 7 is an example of the image reading apparatus in the present invention.

[0044] Specifically, a document reading program for causing the CPU 7A of the control unit 7 to function as each of the above-described processing units is stored in advance in the ROM 7B of the control unit 7. Then, the CPU 7A of the control unit 7 functions as each of the above-described processing units by executing the document reading program stored in the ROM 7B. Note that some or all of the processing units included in the control unit 7 may be configured by electronic circuits. Further, the document reading program may be a program for causing a plurality of processors to function as each of the processing units included in the control unit 7.

[0045] The detection processing unit 31 detects the position of the first guide member 15A in the document tray 11.

[0046] Specifically, the detection processing unit 31 uses the signal output circuit 16 to detect the position of the first guide member 15A in the document tray 11. For example, the detection processing unit 31 acquires the separation distance between the first guide member 15A and the second guide member 15B based on the electrical signal output from the signal output circuit 16. Further, the detection processing unit 31 may acquire position information indicating the position of the first guide member 15A in the document tray 11 based on the electrical signal output from the signal output circuit 16.

[0047] The restriction processing unit 32 restricts the image reading range in the main scanning direction D1 (the width direction) by the image reading unit 2 to the document width corresponding to the detection result by the detection processing unit 31.

[0048] For example, the restriction processing unit 32 acquires the document width corresponding to the detection result by the detection processing unit 31 using table data indicating the correspondence between the separation distance between the first guide member 15A and the second guide member 15B acquired by the detection processing unit 31 and the document width of the standard size document X. Note that the table data may be stored in advance in the ROM 7B or the storage unit 6.

[0049] For example, the restriction processing unit 32 restricts the driving of a pair of regions extending from both ends to the central part in the main scanning direction D1 of the light source 221 and a pair of regions extending from both ends to the central part in the main scanning direction D1 of the CCD 26, thereby restricting the image reading range.

[0050] The determination processing unit 33 determines the size of the document X based on the size of the document X in the conveyance direction D3 detected from the document X conveyed toward the reading position.

[0051] Specifically, the determination processing unit 33 uses the sensor 17 to detect the size of the document X in the conveyance direction D3 in the document X conveyed toward the reading position. Further, the determination processing unit 33 specifies the size of the document X based on the size of the document X in the conveyance direction D3 and the detection result by the detection processing unit 31.

[0052] The output processing unit 34 reads an image of the document X passing through the reading position using the image reading unit 2, and cuts out and outputs a first output process for cutting out a first region AR10 (see FIG. 4) determined based on a specific end portion IM12 (see FIG. 4) corresponding to the first guide member 15A among both end portions in the main scanning direction D1 (the width direction) in the read image IM10 and the determination result by the determination processing unit 33. The first region AR10 is a region determined based on the specific end portion IM12 in the read image IM10 and is a region having the same size as the size of the document X determined by the determination processing unit 33. The read image IM10 is an image having the same size in the main scanning direction D1 as the document width corresponding to the detection result by the detection processing unit 31 and having a predetermined size in the sub-scanning direction D2.

[0053] By the way, in the image forming apparatus 100, when the size of the document X placed on the document tray 11 is A4 vertical size or letter size, the size difference between the document widths of both sizes is too small to identify whether the document width of the document X is the document width W2 of the A4 vertical size (see FIG. 5) or the document width W1 of the letter size (see FIG. 5). On the other hand, regardless of whether the size of the document X placed on the document tray 11 is A4 vertical size or letter size, a configuration in which the image reading range by the image reading unit 2 is limited to the document width W1 of the letter size can be considered. In this configuration, when the size of the document X placed on the document tray 11 is letter size, it is possible to read all of the image of the document X. However, in this configuration, as shown in FIG. 5, when the size of the document X placed on the document tray 11 is A4 vertical size, the document area IM11 in the read image IM10 is shifted from the specific end IM12 to the center side in the main scanning direction D1 (the width direction) in the read image IM10, so that all of the image of the A4 vertical size document X cannot be read.

[0054] On the other hand, in the image forming apparatus 100 according to the embodiment of the present invention, as described below, it is possible to suppress the reading failure of each image of a plurality of documents X placed on the document tray 11 and having different sizes in the width direction from each other.

[0055] Specifically, in the image forming apparatus 100, when the separation distance between the first guide member 15A and the second guide member 15B acquired by the detection processing unit 31 is included in a specific range including both the document width W2 of the A4 vertical size (see FIG. 5) and the document width W1 of the letter size (see FIG. 5), the image reading range by the image reading unit 2 is limited to the document width W1 of the letter size.

[0056] In addition, when the image reading range is not limited to the document width W1 of the letter size (an example of the specific document width of the present invention) by the restriction processing unit 32, the output processing unit 34 executes the first output processing.

[0057] Further, when the image reading range is restricted to the letter-sized original width W1 by the restriction processing unit 32, the output processing unit 34 reads an image of the original X passing through the reading position using the image reading unit 2, detects a contact end portion IM13 (see FIG. 6) that contacts the first guide member 15A in the read original X (original region IM11) included in the read image IM10 (see FIG. 6), and cuts out and outputs a second region AR20 (see FIG. 6) determined based on the contact end portion IM13 in the read image IM10 and the determination result by the determination processing unit 33. The second region AR20 is a region determined based on the contact end portion IM13 in the read image IM10 and is a region having the same size as the size of the original X determined by the determination processing unit 33.

[0058] Note that when the image reading range is restricted to the letter-sized original width W1 by the restriction processing unit 32, the output processing unit 34 may execute the second output processing when the determination result by the determination processing unit 33 is different from the letter size (an example of the specific size of the present invention), and may execute the first output processing when the determination result by the determination processing unit 33 is the letter size.

[0059] [Original Reading Process] Hereinafter, with reference to FIG. 7, an example of the procedure of the original reading process executed by the control unit 7 in the image forming apparatus 100 will be described together with the image reading method of the present invention. Here, steps S11, S12,... represent the numbers of the processing steps (steps) executed by the control unit 7. The original reading process is executed when an execution instruction for an image reading process for reading an image of the original placed on the original tray 11 is input.

[0060] <Step S11> First, in step S11, the control unit 7 detects the position of the first guide member 15A in the original tray 11. Here, the process of step S11 is an example of the detection step of the present invention and is executed by the detection processing unit 31 of the control unit 7.

[0061] <Step S12> In step S12, the control unit 7 restricts the image reading range by the image reading unit 2 to the document width corresponding to the detection result of the process in step S11. Here, the process in step S12 is an example of the restriction step of the present invention and is executed by the restriction processing unit 32 of the control unit 7.

[0062] <Step S13> In step S13, the control unit 7 determines whether or not the document X has been conveyed from the document tray 11 by the ADF 1.

[0063] Here, when the control unit 7 determines that the document X has been conveyed from the document tray 11 by the ADF 1 (Yes side in S13), the process proceeds to step S14. If the document X has not been conveyed from the document tray 11 by the ADF 1 (No side in S13), the control unit 7 waits for the conveyance of the document X from the document tray 11 in step S13.

[0064] <Step S14> In step S14, the control unit 7 determines the size of the document X based on the size in the conveyance direction D3 of the document X detected from the document X conveyed toward the reading position. Here, the process in step S14 is an example of the determination step of the present invention and is executed by the determination processing unit 33 of the control unit 7.

[0065] <Step S15> In step S15, the control unit 7 determines whether or not the image reading range has been restricted to the letter-size document width W1 by the process in step S12.

[0066] Here, when the control unit 7 determines that the image reading range has been restricted to the letter-size document width W1 by the process in step S12 (Yes side in S15), the process proceeds to step S16. If the image reading range has not been restricted to the letter-size document width W1 (No side in S15), the control unit 7 proceeds the process to step S17.

[0067] <Step S16> In step S16, the control unit 7 executes the second output process. Here, the process of step S16 is an example of the output step of the present invention and is executed by the output processing unit 34 of the control unit 7.

[0068] <Step S17> In step S17, the control unit 7 executes the first output process. Here, the process of step S17 is executed by the output processing unit 34 of the control unit 7.

[0069] <Step S18> In step S18, the control unit 7 determines whether or not the original X remains in the original tray 11. Note that the control unit 7 can determine whether or not the original X remains in the original tray 11 by using an original sensor (not shown) capable of detecting the presence or absence of the original X in the original tray 11.

[0070] Here, when the control unit 7 determines that the original X remains in the original tray 11 (Yes side of S18), the process is shifted to step S13. If the original X does not remain in the original tray 11 (No side of S18), the control unit 7 ends the original reading process.

[0071] As described above, in the image forming apparatus 100, when the image reading range is limited to the letter size original width W1 by the limiting processing unit 32, the second output process is executed. Thereby, the image cutout area from the read image IM10 is determined based on the contact end IM13 instead of the specific end IM12 (see FIG. 6). Therefore, when the size of the original X placed on the original tray 11 is the A4 vertical size, it is possible to read all of the image of the original X. Accordingly, it is possible to suppress reading failures of the images of a plurality of originals X having different sizes in the width direction from each other, such as the A4 vertical size original X and the B5 vertical size original X placed on the original tray 11.

[0072] Note that the image reading unit of the present invention is not limited to the image reading unit 2 and may be a CIS (Contact Image Sensor) provided inside the ADF1.

[0073] Also, the specific manuscript width of the present invention does not have to be limited to the letter size manuscript width W1.

Explanation of Signs

[0074] 1 ADF 2 Image reading unit 3 Image forming unit 4 Paper feeding unit 5 Operation display unit 6 Storage unit 7 Control unit 11 Manuscript tray 15 Manuscript regulating unit 15A First guide member 16 Signal output circuit 17 Sensor 31 Detection processing unit 32 Limiting processing unit 33 Judgment processing unit 34 Output processing unit 100 Image forming apparatus

Claims

1. A document placement unit on which a document to be conveyed along a predetermined conveyance path is placed; An image reading unit that reads an image of the document at a predetermined reading position in the conveyance path; A restricting unit that is provided movably in a width direction orthogonal to the conveyance direction of the document in the document placement unit and restricts the position of the document in the width direction placed on the document placement unit; A detection processing unit that detects the position of the restricting unit in the document placement unit; A limiting processing unit that limits the image reading range in the width direction by the image reading unit to the document width corresponding to the detection result by the detection processing unit; A determination processing unit that determines the size of the document based on the size of the document in the conveyance direction detected from the document conveyed toward the reading position; When the image reading range is restricted to a predetermined specific document width by the limiting processing unit, an output processing unit that reads an image of the document passing through the reading position using the image reading unit, detects a contact end portion that contacts the restricting unit in the document included in the read image, and executes output processing of cutting out and outputting a region determined based on the contact end portion and the determination result by the determination processing unit from the read image; An image reading apparatus comprising:

2. The output processing unit executes the output processing when the determination result by the determination processing unit is different from a specific size corresponding to the specific document width in a case where the image reading range is restricted to the specific document width by the limiting processing unit. The image reading apparatus according to claim 1.

3. The image reading apparatus according to claim 1 or 2, and An image forming unit that forms an image on a sheet based on an image read by the image reading apparatus. An image forming apparatus comprising:

4. A document placement unit on which a document to be conveyed along a predetermined conveyance path is placed, an image reading unit that reads an image of the document at a predetermined reading position in the conveyance path, and a regulating unit that is provided so as to be movable in a width direction orthogonal to the conveyance direction of the document in the document placement unit and regulates the position of the document in the width direction placed on the document placement unit. An image reading method executed by an image reading apparatus comprising: A detection step of detecting the position of the regulating unit in the document placement unit; A limiting step of limiting the image reading range in the width direction by the image reading unit to the document width corresponding to the detection result by the detection step; A determination step of determining the size of the document based on the size of the document in the conveyance direction detected from the document conveyed toward the reading position; When the image reading range is limited to a predetermined specific document width by the limiting step, an output step of reading an image of the document passing through the reading position using the image reading unit, detecting a contact end portion in contact with the regulating unit in the document included in the read image, and executing an output process of cutting out and outputting a region determined based on the contact end portion and the determination result by the determination step from the read image; An image reading method including the above steps.

Images