Document feeder, document reading device with document feeder, and control program and control method for document feeder

Abstract

To provide a document feeder that feeds a sheet-shaped document mounted on a mounting part to image reading position by image reading means, in which the image of the document is entirely read by the image reading means while effectively utilizing convenience by a document size detection mechanism and a read image with no inclination is obtained.SOLUTION: In an image forming apparatus 10, a document 100 is mounted on a document mounting tray 14a of a document feeder 14 and document guides 14c and 14c are aligned with both side edges of the document 100, so that a size of the document 100 is detected and set as a size to be read by an image reading section (12). When a guide width D which is a mutual distance between the document guides 14c and 14c is enlarged, the size of the document 100 is updated. In a case where the guide width D is reduced, on the other hand, the size of the document 100 is not updated but is made invariable.SELECTED DRAWING: Figure 14

Description

[Technical Field]

[0001] The present disclosure relates to a document feeding device, a document reading device including the document feeding device, and a control program and control method for the document feeding device, and in particular to a document feeding device that has a loading section on which a sheet-like document is placed, and that feeds the document placed on the loading section to an image reading position by an image reading means for reading an image of the document, a document reading device including the document feeding device, and a control program and control method for the document feeding device. [Background technology]

[0002] Some document reading devices equipped with an image reading unit that reads an image of a document have a document size detection function that automatically detects the size of the document. In such document reading devices, the document size detected by the document size detection function is set as the reading size by the image reading unit, but the document size can also be set by manual operation (input). For example, Patent Document 1 discloses a technology related to a document reading device that includes an automatic document size detection unit and a document size operation input unit, and also includes a document size storage unit that, when the document size is manually input through the document size operation input unit, stores and retains the manually input document size until the next manual document size input or the document size is automatically detected by the automatic document size detection unit. The technology disclosed in Patent Document 1 is said to have the advantage that, when consecutively reading multiple documents of the same size, it is not necessary to automatically read or manually input the document size for each document, making it easier to determine the document size. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-238040 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, some document reading devices are equipped with an automatic document feeder (hereinafter referred to as "ADF"). The ADF has a loading section on which sheet-like documents are placed (set), or more precisely, on which multiple documents can be placed in a stack, and is a device that automatically feeds the documents placed on this loading section one by one to an image reading position by an image reading means. In document reading devices equipped with this ADF, the size of the documents placed on the loading section of the ADF is also automatically detected by a document size detection function.

[0005] Specifically, the ADF has a regulating member that regulates both widthwise edges of a document placed on its loading section. The widthwise direction here refers to a direction perpendicular to the document feed direction and along both main surfaces of the document. The regulating member can be manually displaced along the widthwise direction. The size of the document is detected based on the position of the regulating member, specifically, based on the position of the regulating member when both widthwise edges of the document are regulated by the regulating member. At least the widthwise dimension of the document is detected. For this purpose, the position of the regulating member is detected by an appropriate detection means.

[0006] In a document reading device equipped with such an ADF, a user may intentionally set the document size (read size) to a size larger than the document size detected by the document size detection function. For example, this may occur when the document size is larger than A5R and smaller than B5R, and the document size detected by the document size detection function is A5R. In this case, in order for the image reading unit to read the document image in its entirety (without missing parts), the document size must be set to a size larger than A5R, and for this reason, the user intentionally sets such a size. In this case, the user can intentionally set the document size to a size larger than A5R by moving the position of the regulating member so that the document size detected by the document size detection function is larger than A5R.

[0007] For example, the document size is set to B5R by moving the position of the restricting member to a position corresponding to B5R, which is larger than A5R. However, if a document is fed in this state, the document will be skewed, resulting in the image read by the image reading unit being skewed, and in extreme cases, parts (corners) of the read image may be missing. To avoid this problem, the restricting member can be moved to a position where it can restrict both side edges of the document, but doing so would return the document size detected by the document size detection function to A5R. It is also possible to manually set the document size, but doing so would negate the convenience of the document size detection function.

[0008] Therefore, the present disclosure aims to provide a novel document feeding device, a document reading device equipped with the document feeding device, a control program and a control method for the document feeding device, which allows the entire image of the document to be read by an image reading means while enjoying the convenience of the document size detection function and which can obtain a read image without tilt. [Means for solving the problem]

[0009] To achieve this objective, the present disclosure includes a first disclosure relating to a document feeding device, a second disclosure relating to a document reading device equipped with the document feeding device, a third disclosure relating to a control program for the document feeding device, and a fourth disclosure relating to a control method for the document feeding device.

[0010] The first disclosure of the document feeder includes a loading section. Sheet-shaped documents are placed on the loading section; more specifically, multiple documents can be stacked on top of each other. The document feeder of the first disclosure feeds the documents placed on the loading section one by one to an image reading position for reading the image of the document. The first disclosure also includes a regulating member, a size detecting means, and a setting control means. The regulating member regulates both widthwise edges of the document placed on the loading section. The widthwise direction here refers to a direction perpendicular to the document feed direction and along both major surfaces of the document. The size detecting means detects the size of the document based on the position of the regulating member. The setting control means performs predetermined processing, including setting the size of the document (read size), based on the transition of the position of the regulating member.

[0011] The predetermined process includes, for example, a size setting control process. According to this size setting control process, when the position of the restricting member is moved from a position corresponding to the actual size of the document to a position corresponding to a size larger than the actual size of the document, the document size is set according to the detection result by the size detection means. If the position of the restricting member is then moved to a position corresponding to a size smaller than the larger size, the set document size is left unchanged.

[0012] In this size setting control process, when the setting control means sets the size of the document as the position of the regulating member is moved from a position corresponding to the actual size of the document to a position corresponding to a size larger than the actual size of the document, as described above, and further when a predetermined time has elapsed since the size of the document was set, the setting control means may not leave the set size of the document unchanged, that is, may cancel the state in which the set size of the document is unchanged, and may set the size of the document in accordance with the detection result by the size detection means.

[0013] Furthermore, when the detection result by the size detection means conforms to a standard size that complies with a predetermined standard, the setting control means may set the conforming standard size as the size of the document that conforms to the detection result by the size detection means. On the other hand, when the detection result by the size detection means does not conform to a standard size that complies with a predetermined standard, that is, when the detection result by the size detection means belongs to an irregular size that does not conform to the predetermined standard, the setting control means may set a dimension that corresponds to the position of the regulating member as at least the dimension in the width direction of the document.

[0014] The predetermined processing in the first disclosure may include a crop scan mode setting control processing instead of the size setting control processing. According to this crop scan mode setting control processing, when the position of the restricting member is moved from a position corresponding to the actual size of the document to a position corresponding to a size larger than the actual size of the document, the document size is set according to the detection result by the size detection means, and the crop scan mode is also set. The crop scan mode is a mode in which a portion corresponding to the document image is cut out from the read image read by the image reading means and the tilt of the cut out image is corrected.

[0015] In a configuration in which this crop scan mode setting control process is performed as a predetermined process, the setting control means may perform the crop scan mode setting control process when the position of the regulating member is moved from a position corresponding to the actual size of the document to a position corresponding to a size that is larger than the actual size of the document by a predetermined threshold or more.

[0016] In addition, in a configuration in which the crop scan mode setting control process is performed as a predetermined process, an information output means may be further provided, which, when the crop scan mode is set, outputs predetermined information indicating that the crop scan mode has been set.

[0017] A document reading device according to a second aspect of the present disclosure includes the document feeder according to the first aspect of the disclosure, and also includes an image reading unit that reads an image of a document fed to its image reading position.

[0018] A control program for a document feeder according to a third aspect of the present disclosure causes a computer to execute a size detection procedure and a setting control procedure. The document feeder includes a loading section. Sheet-shaped documents are placed on the loading section. The document feeder then feeds the documents placed on the loading section one by one to an image reading position for an image reading unit to read an image of the document. The document feeder further includes a regulating member. The regulating member regulates both side edges of the document placed on the loading section in the width direction. The width direction is perpendicular to the document feed direction and along both main surfaces of the document. The size detection procedure then detects the size of the document based on the position of the regulating member. The setting control procedure then performs predetermined processing, including setting the size of the document based on the transition of the position of the regulating member.

[0019] A control method for a document feeder according to a fourth disclosure of the present disclosure includes a size detection step and a setting control step. The document feeder includes a loading section. Sheet-shaped documents are placed on the loading section. The document feeder then feeds the documents placed on the loading section one by one to an image reading position for image reading by an image reading unit for reading an image of the document. The document feeder further includes a regulating member. The regulating member regulates both side edges of the document placed on the loading section in the width direction. The width direction is a direction perpendicular to the document feed direction and along both main surfaces of the document. The size detection step then detects the size of the document based on the position of the regulating member. The setting control step then performs predetermined processing, including setting the size of the document based on the transition of the position of the regulating member. [Effects of the Invention]

[0020] According to the present disclosure, it is possible to enjoy the convenience of the document size detection function, while allowing the image reading unit to read the entire document image and obtain a read image without tilt. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a perspective view of an image forming apparatus according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a diagram showing a state in which an original is placed on an original tray of the ADF in the first embodiment, as viewed from above. [Figure 3] FIG. 3 is a diagram schematically showing the internal configuration of the ADF in the first embodiment. [Figure 4] FIG. 4 is a block diagram showing the electrical configuration of the image forming apparatus according to the first embodiment. [Figure 5] FIG. 5 is a diagram for explaining how the document size is detected by the document size detection function in the first embodiment. [Figure 6] FIG. 6 is a diagram showing a list of standard document sizes that can be detected by the document size detection function in the first embodiment. [Figure 7] FIG. 7 is a diagram conceptually showing the configuration of the document size detection table in the first embodiment. [Figure 8] FIG. 8 is a diagram showing an example of a copy operation screen in the first embodiment. [Figure 9] FIG. 9 is a diagram showing a state in which an original of a non-standard size is placed on the original tray of the ADF in the first embodiment, and an example of the state of the original size setting key in this state. [Figure 10] FIG. 10 is a diagram for explaining the inconvenience that occurs when copying is performed in the state shown in FIG. [Figure 11] FIG. 11 is a diagram showing a state in which an original of a non-standard size is placed on the original placement tray of the ADF in the first embodiment, and another example of the state of the original size setting key in this state. [Figure 12]FIG. 12 is a diagram for explaining the inconvenience that occurs when copying is performed in the state shown in FIG. [Figure 13] FIG. 13 is a diagram for explaining the disadvantages of a conventional image forming apparatus as a comparison target for the first embodiment. [Figure 14] FIG. 14 is a diagram showing an example of the transition of the position of the document guide and the transition of the state of the document size setting key in the first embodiment. [Figure 15] FIG. 15 is a diagram for explaining the effects of the first embodiment. [Figure 16] FIG. 16 is a memory map conceptually showing the internal configuration of the RAM of the main storage unit in the first embodiment. [Figure 17] FIG. 17 is a flowchart showing the flow of the document size setting control task in the first embodiment. [Figure 18] FIG. 18 is a flowchart showing the flow of the flag setting process in the first embodiment. [Figure 19] FIG. 19 is a flow diagram showing the flow of a part of the document size setting control task in the second embodiment of the present disclosure. [Figure 20] FIG. 20 is a diagram conceptually showing the configuration of a document size detection table in the third embodiment of the present disclosure. [Figure 21] FIG. 21 is a diagram showing an example of the state of the document keys in response to the transition of the document guide position in the third embodiment. [Figure 22] FIG. 22 is a diagram for explaining the effects of the third embodiment. [Figure 23] FIG. 23 is a diagram showing an example of a transition of the position of the document guide, a transition of the state of the document size setting key, and a copy operation screen in the fourth embodiment of the present disclosure. [Figure 24] FIG. 24 is a diagram for explaining the effects of the fourth embodiment. [Figure 25] FIG. 25 is a diagram showing an example of the transition of the document guide position, the transition of the document size setting key mode, and the transition of the copy operation screen in the fourth embodiment. [Figure 26]FIG. 26 is a flowchart showing the flow of the crop scan mode setting control task in the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] [First Example] The first embodiment of the present disclosure will be described using an image forming apparatus 10 shown in FIG. 1 as an example.

[0023] Image forming apparatus 10 according to the first embodiment is a so-called multifunction peripheral (MFP) having multiple functions, such as a copy function, an image scanner function, a printer function, and a fax function. FIG. 1 is a perspective view of image forming apparatus 10, showing the front, top, and left side of image forming apparatus 10 when installed in a usable state. That is, the up-down direction in FIG. 1 corresponds to the up-down direction of image forming apparatus 10. The diagonally lower right in FIG. 1 corresponds to the front of image forming apparatus 10, and the diagonally upper left in FIG. 1 corresponds to the rear of image forming apparatus 10. The diagonally lower left in FIG. 1 corresponds to the left of image forming apparatus 10, and the diagonally upper right in FIG. 1 corresponds to the right of image forming apparatus 10.

[0024] An image reading unit 12, which is an example of an image reading means, is provided at the top of the image forming apparatus 10. The image reading unit 12 performs image reading processing, which involves reading an image of an original 100 (described later) and outputting two-dimensional read image data corresponding to the read image. To this end, the image reading unit 12 has a document table (not shown) on which the original 100 is placed. The document table is formed of a transparent material such as glass in a roughly rectangular flat plate shape, and is provided with both main surfaces aligned horizontally. The upper of the two main surfaces of the document table is the surface on which the original 100 is placed. Additionally, provided below the document table are an image reading unit having a light source, mirrors, lenses, line sensors, etc. (not shown), as well as a drive mechanism for moving (scanning) an image reading position P (described later) by the image reading unit along the underside of the document table. That is, with the document 100 placed on the document table, the image reading position P of the image reading unit is moved by a drive mechanism, and the image of the document 100 is read by a so-called fixed reading method. Furthermore, above the document table, an ADF 14 is provided, which also serves as a document pressing cover for pressing down the document 100 placed on the document table.

[0025] The ADF 14 is provided so that it can be freely switched between a state in which the top surface of the document table (document placement surface) is exposed to the outside and a state in which the top surface of the document table is covered. For this reason, the ADF 14 is connected to the main body (housing) of the image forming apparatus 10 via an appropriate movable support member such as a hinge (not shown). Note that FIG. 1 shows a state in which the ADF 14 covers the top surface of the document table. Furthermore, when the ADF 14 is in a state in which the top surface of the document table is covered as shown in FIG. 1, it performs its original function, that is, the function of automatically feeding sheet-like documents 100 one by one to the image reading position P described above.

[0026] The ADF 14 will be described in detail later, but the ADF 14 has a document placement tray 14a as an example of a placement section. Sheet-like documents 100 can be placed on the document placement tray 14a; more precisely, multiple documents 100, 100, ... can be placed in a stack. The ADF 14 then automatically takes in the documents 100 placed on the document placement tray 14a one by one and transports them along a document transport path 140, which will be described later. Along the way, the documents 100 pass through an image reading position P, or more precisely, the image reading position P is fixed. This causes the image of the documents 100 to be read, or read using a so-called skimming method. The documents 100 are then discharged to a document discharge tray 14b.

[0027] Furthermore, an image forming unit 16 serving as an image forming means is provided below the image reading unit 12. This image forming unit 16 performs image formation processing, i.e., printing, on a sheet-like image recording medium (not shown) based on appropriate image data, such as image data after image processing by the image processing unit 50 (described later). This image formation processing is performed, for example, by a known electrophotographic method. For this purpose, the image forming unit 16 includes a photosensitive drum, a charging device, an exposure device, a developing device, a transfer device, a fixing device, a cleaning device, a static elimination device, and other components (not shown). The paper after image formation processing by the image forming unit 16, i.e., the printed matter, is discharged onto a paper output tray 18. The paper output tray 18 is provided between the image forming unit 16 and the image reading unit 12, in the so-called cavity of the image forming apparatus 10. Furthermore, the image forming unit 16 is not limited to an electrophotographic method, and may perform image formation processing using, for example, an inkjet method.

[0028] A paper feed unit 20 serving as a paper feed means is provided below the image forming unit 16, in other words, at the bottom of the image forming apparatus 10. The paper feed unit 20 has a plurality of, for example, four, paper feed cassettes 20a, 20a, .... Each of the paper feed cassettes 20a, 20a, ... stores paper of an appropriate size, for example, paper of different sizes. In addition, a manual feed tray (not shown) serving as an auxiliary paper feed tray is provided at an appropriate position of the image forming apparatus 10, for example, on the right side of the image forming apparatus 10. The paper feed unit 20 uses one of the paper feed cassettes 20a, 20a, ... or the manual feed tray as a paper feed source and supplies paper sheets one by one from the paper feed source to the image forming unit 16.

[0029] In addition, a roughly rectangular plate-shaped operation unit 22 is provided on top of the image forming apparatus 10, at the front of the main body of the image forming apparatus 10. One side edge of the operation unit 22 is connected to the main body of the image forming apparatus 10, and the operation unit 22 is provided rotatable about the one side edge as an axis. One main surface of the operation unit 22 (the main surface facing upward in FIG. 1) is an operation surface, and a display 22b with a touch panel 22a is provided on this operation surface.

[0030] The display 22b with touch panel 22a is a component that integrally combines the display 22b having a rectangular display surface and the sheet-like touch panel 22a that is provided so as to overlap the display surface of the display 22b. The touch panel 22a is an operation receiving unit that can receive touch operations from a user (not shown) using the image forming apparatus 10, and is, for example, a projected capacitive panel. The display 22b is a display unit that displays various screens, including a copy operation screen 300 (see FIG. 8 ), which will be described later, and is, for example, a liquid crystal display (LCD). Note that the touch panel 22a is not limited to a projected capacitive panel, and may be a panel of other types, such as a surface capacitive panel, an electromagnetic induction panel, a resistive film panel, or an infrared panel. The display 22b is not limited to a liquid crystal display, and may be, for example, an organic electroluminescence (EL) display.

[0031] A user typically stands in front of the image forming apparatus 10 to use the image forming apparatus 10, and in particular to operate the operation unit 22. To ensure good operability and visibility of the operation surface of the operation unit 22 by the user, the operation unit 22 is provided rotatable about the coupling portion with the image reading unit 12 as described above, i.e., the angle of the operation surface relative to the user is adjustable. In addition to the touch panel 22a, the operation unit 22 also has appropriate hardware switches such as push button switches. In addition to the display 22b, the operation unit 22 also has appropriate light-emitting means such as a light-emitting diode (LED).

[0032] 2, the ADF 14 has a pair of document guides 14c and 14c as an example of a regulating means. The document guides 14c and 14c regulate the position of both side edges of the document 100 in the width direction of the document 100 placed on the document placement tray 14a, which is perpendicular to the direction (feed direction) of transport of the document 100 by the ADF 14 and extends along both main surfaces of the document 100, i.e., in the transport width direction (the front-to-rear direction of the image forming apparatus 10). Specifically, the document guides 14c and 14c are manually displaceable along the transport width direction as indicated by arrows 14d and 14d in FIG. 2, and mechanically regulate the position of both side edges of the document 100 by abutting against the both side edges of the document 100, in other words, by sandwiching the both side edges of the document 100. 2, for the sake of convenience, the outline of the document 100 is shown by a two-dot chain line. The document guides 14c and 14c are displaced symmetrically in conjunction with each other, that is, when one is displaced, the other is displaced symmetrically in conjunction with this.

[0033] Additionally, the ADF 14 has a guide width detector 14e (see FIG. 4), which will be described later, as a restriction position detector. The guide width detector 14e detects the restriction position established by the document guides 14c and 14c, and thus detects a guide width D (see FIG. 5), which is the distance between the document guides 14c and 14c. Therefore, for example, when the document guides 14c and 14c restrict the positions of both side edges of the document 100, the guide width D roughly corresponds to the width W (see FIG. 5), which is the dimension of the document 100 in the transport width direction. Although not illustrated or described in detail, the guide width detector 14e includes a variable resistor that exhibits a resistance value corresponding to the position of one or both of the document guides 14c and 14c, and detects the guide width D based on the resistance value of the variable resistor. Alternatively, the guide width detector 14e may be configured to detect the position of one or both of the document guides 14c and 14c by using an appropriate sensor such as an optical sensor, and thereby detect the guide width D.

[0034] Furthermore, the ADF 14 has a plurality of, for example, two, flat, protruding document detection pieces 14f and 14g. These two document detection pieces 14f and 14g are disposed at approximately the center of the document loading tray 14a in the transport width direction and at appropriate positions different from each other in the transport direction of the document loading tray 14a. When no external force is applied to them, particularly when no external force is applied from above, each of the document detection pieces 14f and 14g protrudes above the upper surface (document loading surface) of the document loading tray 14a, i.e., is in an OFF state. On the other hand, when an external force is applied to each of the document detection pieces 14f and 14g, for example, when the document is covered by a document 100, the weight of the document 100 pushes each of the document detection pieces 14f and 14g into the document loading tray 14a, i.e., is in an ON state, i.e., is configured to do so.

[0035] In addition, the ADF 14 has two document length sensors 14h and 14i (see FIG. 3), which will be described later, for detecting the states of the document detection pieces 14f and 14g, respectively. These two document length sensors 14h and 14i are provided in the document placement tray 14a. One document length sensor 14h, or the first length sensor 14h, detects the state of one document detection piece 14f, or the first detection piece 14f. The other document length sensor 14i, or the second length sensor 14i, detects the state of the other document detection piece 14g, or the second detection piece 14g. Each of these document length sensors 14h and 14i is, for example, an optical sensor, and more specifically, a transmission-type optical sensor. In addition, each of the document length sensors 14h and 14i cooperates with each of the document detection pieces 14f and 14g to form a document length detection means for roughly detecting the length dimension L (see Figure 5), which is the dimension in the transport direction of the document 100.

[0036] 3, focusing on the inside of ADF 14, ADF 14 has a document transport path 140 that runs from document feed opening 14k of document placement tray 14a to document discharge opening 14m of document discharge tray 14b. When viewed from the side, document transport path 140 has a generally U-shaped (or generally C-shaped) shape.

[0037] A pickup roller 14n is provided near the paper feed opening 14k of the document transport path 140 to pick up the documents 100 placed on the document loading tray 14a one by one from the document loading tray 14a. The documents 100 picked up from the document loading tray 14a by the pickup roller 14n are taken into the document transport path 140 via the paper feed opening 14k. For this purpose, a paper feed roller 14p is provided at the end of the document transport path 140 on the paper feed opening 14k side, that is, at the upstream end in the transport direction of the documents 100.

[0038] A plurality of transport rollers (strictly speaking, transport roller pairs) 14q, 14q, ... are provided at appropriate positions on the document transport path 140 for transporting the document 100 taken into the document transport path 140 along the document transport path 140. In addition, an image reading position P is disposed at a position on the document transport path 140 facing the document table. Among the transport rollers 14q, 14q, ..., transport roller 14q' located immediately before the image reading position P in the transport direction of the document 100 (on the upstream side closest to the image reading position P) also serves as a registration roller for adjusting the timing of feeding the document 100 to the image reading position P. In addition, the image reading position P extends in a direction perpendicular to the plane of the paper in FIG. 3 (the main scanning direction). As the original 100 is transported along the original transport path 140, the original 100 passes through the image reading position P, causing the image reading position P to move relatively in the transport direction (sub-scanning direction) of the original 100, and as a result, the image of the original 100 is read using a skimming method.

[0039] The document 100 that has passed through the image reading position P is discharged to the document discharge tray 14b through a paper discharge port 14m that is the downstream end of the document transport path 140. For this reason, a paper discharge roller 14r is provided at the paper discharge port 14m. Each of the pickup roller 14n, the paper feed roller 14p, and the transport rollers 14q, 14q, ..., including the paper discharge roller 14r, is driven by a roller drive motor (not shown) that serves as a roller drive source.

[0040] Furthermore, a plurality of document transport sensors 14t, 14t, ... are provided at appropriate positions on the document transport path 140 to detect the document 100 being transported along the document transport path 140, in other words, to detect that the document 100 has passed through each position. Each of these document transport sensors 14t, 14t, ... is, for example, an optical sensor, and more specifically, a reflective optical sensor.

[0041] Additionally, tilt sensor 14v is provided at an appropriate position upstream in the transport direction of original 100 on original transport path 140, for example, between original transport sensor 14t on the most upstream side and paper feed roller 14p; more precisely, two tilt sensors 14v and 14v are provided. These two tilt sensors 14v and 14v are tilt degree detection means for detecting the degree of tilt of original 100 transported along original transport path 140. Incidentally, each of tilt sensors 14v and 14v is, for example, an optical sensor, and more specifically, a reflective optical sensor.

[0042] In addition, a document placement sensor 14x is provided at an appropriate position on the document placement tray 14a, for example, near the paper feed slot 14k within the document placement tray 14a. This document placement sensor 14x is a document placement detection unit that detects whether a document 100 is placed on the document placement tray 14a. This document placement sensor 14x is also, for example, a reflective optical sensor. Furthermore, document length sensors 14h and 14i are provided at appropriate positions within the document placement tray 14a, specifically corresponding to the positions of the document detection pieces 14f and 14g described above. Note that the document detection pieces 14f and 14g are not shown in FIG. 3.

[0043] The electrical configuration of the image forming apparatus 10 will now be described with reference to FIG. 4. As shown in FIG. 4, the image forming apparatus 10 includes a control unit 30. The control unit 30 is connected to the image reading unit 12, the ADF 14, the image forming unit 16, the paper feed unit 20, and the operation unit 22 via a bus 40. The control unit 30 is also connected to an image processing unit 50, an auxiliary storage unit 52, a communication unit 54, and the like via the bus 40. The image forming apparatus 10 includes various other elements, but illustrations and descriptions of elements not directly related to the gist of this disclosure will be omitted here. The image reading unit 12, the ADF 14, the image forming unit 16, and the paper feed unit 20 are as described above. In particular, the ADF 14 includes a guide width detection unit 14e, a first length sensor 14h, a second length sensor 14i, and a document placement sensor 14x.

[0044] The control unit 30 is a control means that controls the entire image forming apparatus 10. To this end, the control unit 30 has a computer, such as a CPU 30a, as a control execution means. The control unit 30 also has a main memory unit 30b as a main memory means that can be directly accessed by the CPU 30a. The main memory unit 30b includes, for example, a ROM and a RAM (not shown). The ROM stores a control program (firmware) for controlling the operation of the CPU 30a. The RAM forms a working area and a buffer area when the CPU 30a executes processing in accordance with the control program.

[0045] The image processing unit 50 is an image processing means that performs appropriate image processing on various image data, including the above-mentioned scanned image data. The image processing by the image processing unit 50 includes a scaling process that enlarges or reduces the size of an image based on the image data, and a density adjustment process that adjusts the density of an image based on the image data. The image data after image processing by the image processing unit 50 is used for image formation processing by the image forming unit 16, or is stored in the auxiliary storage unit 52, or is output (transmitted) to the outside via the communication unit 54.

[0046] The auxiliary storage unit 52 is an auxiliary storage means for storing various data such as image data after image processing by the image processing unit 50. The auxiliary storage unit 52 may include, for example, a hard disk drive (not shown). The auxiliary storage unit 52 may also include a rewritable non-volatile memory such as a flash memory.

[0047] The communication unit 54 is a communication means for two-way communication via a communication network (not shown). The communication network referred to here includes a LAN, the Internet, a public switched telephone network, etc. The LAN also includes a wireless LAN, particularly Wi-Fi (registered trademark).

[0048] The image forming apparatus 10 according to the first embodiment has a document size detection function, which automatically detects the size of the document 100 placed on the document placement tray 14a of the ADF 14.

[0049] Specifically, as shown in FIG. 5 , the size of the original 100 is detected based on the guide width D when the original 100 is placed on the original tray 14a of the ADF 14 and the respective states of the first and second detection pieces 14f and 14g. Strictly speaking, it is determined which of several standard sizes the original 100 conforms to. This detection of the size of the original 100 using the original size detection function is premised on the fact that the positions of both side edges of the original 100 are properly regulated by the original guides 14c and 14c. Note that in FIG. 5 , for ease of explanation, the outline of the original 100 is indicated by a two-dot chain line, and the original guides 14c and 14c are spaced apart from both side edges of the original 100. As described above, whether the original 100 is placed on the original tray 14a is detected by the original placement sensor 14x, and the guide width D is detected by the guide width detection unit 14e. Furthermore, the state of the first detection piece 14f is detected by a first length sensor 14h, and the state of the second detection piece 14g is detected by a second length sensor 14i.

[0050] The "predetermined standard" here refers to the well-known A and B series of paper dimensions. The document size detection function of the first embodiment can detect eight standard sizes, A3R, A4, B4R, B5, A4R, A5, B5R, and A5R, as shown in FIG. 6. The standard sizes A3R, B4R, A4R, B5R, and A5R, each ending in "R," are sizes when the document 100 is placed on the document tray 14a with its longitudinal direction aligned with the transport direction of the ADF 14. In FIG. 6, W denotes the width dimension, and L denotes the length dimension. As shown in FIG. 5, the width dimension W denotes the dimension of the document 100 in the transport width direction, and the length dimension L denotes the dimension of the document 100 in the transport direction.

[0051] To realize this document size detection function, a document size detection table 200 as shown in FIG. 7 is provided, and is incorporated in detail into the control program described above. That is, when a document 100 is placed on the document tray 14a of the ADF 14, the guide width D and the states of the first and second detection pieces 14f and 14g are compared with the document size detection table 200 to detect the size of the document 100. For example, if the guide width D is less than 165 mm and the first and second detection pieces 14f and 14g are both in the OFF state, the size of the document 100 is detected as A5R. If the guide width D is 165 mm or greater but less than 196 mm, the first detection piece 14f is in the ON state, and the second detection piece 14g is in the OFF state, the size of the document 100 is detected as B5R. Furthermore, when the guide width D is equal to or greater than 196 mm and less than 234 mm, the first detection piece 14f is in the ON state, and the second detection piece 14g is in the OFF state, the size of the original 100 is detected as A4R.

[0052] Note that the hatched pattern in FIG. 7 indicates that there is no standard size that corresponds to the combination of the guide width D and the states of the first and second detection pieces 14f and 14g. The size of the original 100 that corresponds to this combination is not a standard size but is a so-called irregular size, but is detected as a standard size. For example, if the guide width D is 165 mm or more but less than 196 mm and the first and second detection pieces 14f and 14g are both OFF, the size of the original 100 is detected as B5R, although it is an irregular size rather than a standard size. Similarly, if the guide width D is 165 mm or more but less than 196 mm and the second detection piece 14g is ON (regardless of the state of the first detection piece 14f), the size of the original 100 is detected as B5R, although it is an irregular size rather than a standard size.

[0053] The detection result by this document size detection function is displayed on the display 22b. For example, in the copy function, a copy operation screen 300 as shown in Fig. 8 is displayed on the display 22b. This copy operation screen 300 has an original size setting key 302, which is an operator (software operator) for setting the size of the document 100, and an appropriate character string 302a indicating the size of the document 100 detected by the document size detection function is attached to this original size setting key 302. Note that Fig. 8 shows an example in which the character string 302a indicates that the size of the document 100 detected by the document size detection function is A4R. In addition to the original size setting key 302, the copy operation screen 300 also has appropriate operators arranged thereon, such as a start key 304 for instructing the start of copying and a numeric keypad 306 for setting the number of copies. Additionally, the copy operation screen 300 is provided with appropriate indicators, such as a display 308 for displaying the number of copies set using the numeric keypad 306, and a schematic diagram 310 that simulates the appearance of the image forming apparatus 10. Furthermore, the schematic diagram 310 is displayed in a manner that allows the user to intuitively recognize the paper feed source. The schematic diagram 310 in Fig. 8 indicates that the paper feed source is the paper feed cassette 20a containing A4 paper.

[0054] As described above, the document size detection function of the first embodiment detects an irregular-sized document 100 as being of an appropriate standard size. For example, if the size of the document 100 is larger than A5R but smaller than B5R, specifically if the width dimension W of the document 100 is 164 mm, the size of the document 100 is detected as A5R. This state is illustrated in FIG. 9. It is assumed that the length dimension L of the document 100 is, for example, 220 mm.

[0055] That is, as shown in Fig. 9A, when an irregular-sized document 100 having a width W of 164 mm is placed on document tray 14a of ADF 14 and document guides 14c and 14c are aligned with both side edges of document 100, the size of document 100 is detected as A5R. Then, the detected size of document 100, i.e., A5R, is represented by character string 302a added to document size setting key 302 as shown in Fig. 9B. If copying is performed in this state, problems such as those shown in Fig. 10 may occur.

[0056] That is, as shown in FIG. 10A, the width dimension W of the original 100 is 164 mm, whereas the detected size by the original size detection function is A5R as shown in FIG. 10B. That is, the width dimension W of the detected size is 148 mm, which is smaller than the width dimension W of the original 100. When this detected size by the original size detection function is set as the size of the original 100, that is, when it is set as the read size by the image reading unit 12, the image of the original 100 cannot be read by the image reading unit 12 in its entirety. As a result, as shown in FIG. 10C, the image read by the image reading unit 12 may have missing parts, particularly missing parts in the width direction of the read image (the vertical direction in FIG. 10C). When this missing part occurs in the read image, the image of the printed matter may also have missing parts, as shown in FIG. 10D. 10C, the length dimension L of the read image is the same as the length dimension L of the original 100. In other words, the image of the original 100 is read entirely by the image reading unit 12 in the length direction of the original 100. Therefore, no gaps are generated in the read image in the length direction of the read image. However, in the case of the printed matter shown in FIG. 10D, the length dimension L is smaller than the length dimension of the original 100, so gaps may be generated in the image of the printed matter in the length direction.

[0057] To avoid the problem shown in Fig. 10, it is conceivable that the document guides 14c and 14c, which are in the state shown in Fig. 9A, are moved to a position corresponding to B5R, as shown in Fig. 11A, particularly as indicated by arrows 400 and 400 in Fig. 11A. Then, the size detected by the document size detection function becomes B5R. This detected size, B5R, is then represented by the character string 302a of the document size setting key 302, as shown in Fig. 11B. Making a copy in this state avoids the problem shown in Fig. 10. However, another problem may occur, as shown in Fig. 12.

[0058] That is, as shown in FIG. 12A, the width W of document 100 is 164 mm, whereas the detected size by the document size detection function is B5R as shown in FIG. 12B. That is, the width W of the detected size is 182 mm, which is larger than the width W of document 100. By setting this detected size by the document size detection function as the size of document 100, i.e., as the read size by image reading unit 12, the entire image of document 100 is read by image reading unit 12. However, because both side edges of document 100 are not constrained by document guides 14c and 14c, document 100 tilts obliquely during transport. As a result, as shown in FIG. 12C, the image read by image reading unit 12 is also tilted obliquely, and in extreme cases, a portion of the read image may be missing. Furthermore, as shown in FIG. 12D, the image on the printed matter may also be tilted obliquely, and in extreme cases, a portion of the image may be missing.

[0059] To avoid the problem shown in FIG. 12, it is conceivable to realign the document guides 14c and 14c, which are in the state shown in FIG. 11A, with the side edges of the document 100, as shown in FIG. 13A, particularly as indicated by arrows 410 and 410 in FIG. 13A. In this case, the size detected by the document size detection function would be A5R again, as would be the case in the past. Furthermore, as shown in FIG. 13B, the character string 302a of the document size setting key 302 also reverts to the state indicating the detected size A5R. Therefore, if a copy is made in this state, the problem shown in FIG. 10 may occur again. While the size of the document 100 can be arbitrarily set by operating the document size setting key 302, or more precisely, by appropriate manual operations including operating the document size setting key 302, doing so would prevent the user from enjoying the convenience of the document size detection function.

[0060] Therefore, in this first embodiment, the following measures are taken to enable the image reading unit 12 to read the entire image of the original 100 while enjoying the convenience of the original size detection function and to obtain a read image without tilt.

[0061] That is, in the first embodiment, as shown in the left diagram of Fig. 14A, when an irregular-sized document 100 having a width W of 164 mm is placed on document tray 14a of ADF 14 and document guides 14c and 14c are aligned with both side edges of document 100, the size of document 100 detected by the document size detection function becomes A5R. Then, as shown in the right diagram of Fig. 14A, this detected size, A5R, is represented by character string 302a of document size setting key 302.

[0062] In this state, as shown in the left diagram of Fig. 14B, and particularly as indicated by arrows 420 and 420 in the left diagram of Fig. 14B, document guides 14c and 14c are moved to positions corresponding to B5R, so that the document size detected by the document size detection function becomes B5R. Then, as shown in the right diagram of Fig. 14B, this detected size of B5R is represented by character string 302a of document size setting key 302.

[0063] Then, as shown in the left diagram of Fig. 14C, and particularly as indicated by arrows 430 and 430 in the left diagram of Fig. 14C, document guides 14c and 14c are realigned with both side edges of document 100. In this case, conventionally, the detected size by the document size detection function would be reverted to A5R, as described above, or would return to that state. However, according to the first embodiment, the detected size by the document size detection function remains B5R, or is unchanged (fixed). Therefore, as shown in the right diagram of Fig. 14C, character string 302a of document size setting key 302 also remains in the state indicating the detected size B5R.

[0064] That is, in the first embodiment, when the positions of the document guides 14c and 14c are moved from a position corresponding to the actual size of the document 100 to a position corresponding to a larger size, in other words, when the guide width D transitions from a state in which it is matched to the width dimension W of the document 100 to a state in which it is wider than that, the document size detection function is enabled, that is, the size detected by the document size detection function is set as the size (read size) of the document 100. On the other hand, when the positions of the document guides 14c and 14c are moved from a position corresponding to a larger size to a position corresponding to a smaller size, in other words, when the guide width D transitions from a wide state to a narrow state, the document size detection function is disabled, that is, updating of the size (read size) of the document 100 is prohibited.

[0065] 14C, the image of the original 100 is read in its entirety by the image reading unit 12, and a read image without tilt can be obtained. Moreover, the convenience of the original size detection function, that is, the ease of setting the size of the original 100, can be enjoyed.

[0066] Specifically, as shown in FIG. 15A, the width W of document 100 is 164 mm, whereas the detected size by the document size detection function is B5R as shown in FIG. 15B. That is, the width W of the detected size is 182 mm, which is larger than the width W of document 100. Therefore, by setting the detected size by the document size detection function as the size (read size) of document 100, the image of document 100 is read in its entirety by image reading unit 12. Furthermore, because both side edges of document 100 are constrained by document guides 14c and 14c, document 100 does not tilt obliquely during transport. In other words, document 100 is transported in an appropriate posture. As a result, a read image without any missing or tilted portions is obtained, as shown in FIG. 15C. Similarly, the image of the printed matter is also an ideal image without any missing or tilted portions, as shown in FIG. 15D. Moreover, this effect can be obtained by utilizing the convenience of the document size detection function, that is, by the extremely simple operation of moving the positions of the document guides 14c and 14c.

[0067] 14B, the size of the original 100 is set, but this set size of the original 100 is canceled when the ADF 14 has finished feeding all of the originals 100 placed on the original tray 14a to the image reading position P of the image reading unit 12. Also, even if the ADF 14 has not fed all of the originals 100 placed on the original tray 14a to the image reading position P of the image reading unit 12, the set size of the original 100 is also canceled when all of the originals 100 placed on the original tray 14a are removed from the original tray 14a.

[0068] 16 shows a memory map 500 conceptually illustrating the internal configuration of the RAM of the main storage unit 30b. As shown in this memory map 500, the RAM has a program storage area 510 and a data storage area 550.

[0069] The control programs described above are stored in the program storage area 510. Specifically, the control programs include a display control program 512, an operation detection program 514, an image reading control program 516, an ADF control program 518, an image processing control program 520, an image forming control program 522, a paper feed control program 524, an auxiliary storage control program 526, and a communication control program 528. The control programs also include a document size setting control program 530.

[0070] The display control program 512 is a program for generating display screen data required to display each screen, such as the copy operation screen 300, on the display 22b. The operation detection program 514 is a program for detecting the operation state of the touch panel 22a. The image reading control program 516 is a program for controlling the image reading unit 12. The ADF control program 518 is a program for controlling the ADF 14. The image processing control program 520 is a program for controlling the image processing unit 50. The image forming control program 522 is a program for controlling the image forming unit 16. The paper feed control program 524 is a program for controlling the paper feed unit 20. The auxiliary storage control program 526 is a program for controlling the auxiliary storage unit 52. The communication control program 528 is a program for controlling the communication unit 54. The original size setting control program 530 is a program for causing the CPU 30a to execute an original size setting control task, which will be described later.

[0071] Meanwhile, various types of data are stored in the data storage area 550. The various types of data include display image generation data 552, operation data 554, setting data 556, and the like.

[0072] The display image generation data 552 is data such as polygon data and texture data used to generate display screen data based on the above-mentioned display control program 512. The operation data 554 is data representing the operation state of the touch panel 22a, and more specifically, is time-series data representing the touch position (coordinates) of the user on the touch panel 22a. The setting data 556 is data representing appropriate setting contents such as the size (scanning size) of the original 100.

[0073] As described above, in the first embodiment, when the guide width D transitions from a state in which it is adjusted to the width dimension W of the original 100 to a state in which it is wider than that, the original size detection function is enabled, that is, the size detected by the original size detection function is set as the size (read size) of the original 100. When the guide width D transitions from a wide state to a narrow state, the original size detection function is disabled, that is, updating of the size (read size) of the original 100 is prohibited. To achieve this control, the CPU 30a executes an original size setting control task in accordance with the original size setting control program 530. The flow of this original size setting control task is shown in FIG. 17. The CPU 30a executes this original size setting control task when (one or more) originals 100 are placed on the original tray 14a, that is, when this is detected by the original placement sensor 14X. In addition, when the document size setting control task is executed, the document size update determination flag Fa and the document size update prohibition flag Fb, which will be described later, are each set to a value of 0, that is, the document size update determination flag Fa and the document size update prohibition flag Fb are each turned OFF (lowered).

[0074] According to this document size setting control task, first, in step S1, the CPU 30a acquires guide width information indicating the guide width D from the guide width detection unit 14e, and acquires document detection piece information indicating the states of the document detection pieces 14f and 14g from the document length sensors 14h and 14i. Then, the CPU 30a proceeds to step S3.

[0075] In step S3, the CPU 30a detects (specifies) the size of the original 100 based on the information acquired in step S1, that is, by comparing the information acquired in step S1 with the above-mentioned original size detection table 200 (FIG. 7). Then, the CPU 30a advances the process to step S5.

[0076] In step S5, the CPU 30a determines whether the size of the original 100 remains unchanged over a predetermined confirmation time Ta, more specifically, whether the size of the original 100 detected in step S3 remains unchanged. If the size of the original 100 remains unchanged over the confirmation time Ta (S5: YES), the CPU 30a proceeds to step S7. On the other hand, if the size of the original 100 does not remain unchanged over the confirmation time Ta (S5: NO), the CPU 30a returns the process to step S1. The confirmation time Ta is an appropriate time for determining (confirming) whether the size of the original 100 has been changed by manual operation, particularly whether the original guides 14c and 14c have been moved, and is, for example, 200 ms.

[0077] In step S7, the CPU 200a performs a flag setting process, which will be described with reference to FIG.

[0078] According to this flag setting process, in step S101, the CPU 30a determines whether the document size update determination flag Fa is set to 0, i.e., whether the document size update determination flag Fa is in an OFF state. The document size update determination flag Fa is an index indicating whether the size of the document 100 detected by the document size detection function has been updated, more specifically, whether the size of the document 100 has been updated by widening the guide width D. That is, when the document size update determination flag Fa has a value of 0, it indicates that the size of the document 100 has not been updated. When the document size update determination flag Fa has a value of 1, i.e., when the flag is in an ON state (standing), it indicates that the size of the document 100 has been updated. As described above, the document size update determination flag Fa is set to 0 when the document size setting control task is executed. In step S101, if the document size update determination flag Fa is set to 0 (S101: YES), the CPU 30a proceeds to step S103. On the other hand, if the document size update determination flag Fa is 1 (S101: NO), the CPU 30a advances the process to step S107, which will be described later.

[0079] In step S103, the CPU 30a determines whether the guide width D has increased. This determination is made based on a comparison between the guide width D when the previous flag determination process (step S7) was executed (strictly speaking, the guide width D related to the detected size of the document 100 in step S3 (i.e., the guide width D that serves as the basis for the detected size)) and the guide width D when the flag determination process is executed this time. If the guide width D has increased (S103: YES), the CPU 30a proceeds to step S105. On the other hand, if the guide width D has not increased (S105: NO), the CPU 30a temporarily ends the flag setting process.

[0080] In step S105, the CPU 30a sets the document size update determination flag Fa to 1. Then, the CPU 30a temporarily ends the flag setting process.

[0081] In contrast, when the CPU 30a proceeds from step S101 to step S107, it determines in step S107 whether the guide width D has narrowed. The determination in step S107, like the determination in step S103, is made based on a comparison between the guide width D when the flag determination process was executed last time and the guide width D when the flag determination process is executed this time. If the guide width D has narrowed (S107: YES), the CPU 30a proceeds to step S109. On the other hand, if the guide width D has not narrowed (S107: NO), the CPU 30a temporarily ends the flag setting process.

[0082] In step S109, the CPU 30a sets the document size update determination flag Fa to 0. At the same time, the CPU 30a sets the document size update prohibition flag Fb to 1. The document size update prohibition flag Fb is an index indicating whether or not setting the size of the document 100 detected by the document size detection function is prohibited, i.e., whether or not the document size detection function is disabled. That is, when the document size update prohibition flag Fb has a value of 0, it indicates that setting the size of the document 100 detected by the document size detection function is not prohibited, i.e., it indicates that the document size detection function is enabled. On the other hand, when the document size update prohibition flag Fb is 1, it indicates that setting the size of the document 100 detected by the document size detection function is prohibited, i.e., it indicates that the document size detection function is disabled. After executing step S109, the CPU 30a temporarily ends the flag setting process.

[0083] Returning to FIG. 17, after completing the flag setting process in step S7, the CPU 30a proceeds to step S9. Then, in step S9, it is determined whether the document size update prohibition flag Fb is set to 0. If the document size update prohibition flag Fb is set to 0, that is, if the document size detection function is enabled (S9: YES), the CPU 30a proceeds to step S11. On the other hand, if the document size update prohibition flag Fb is set to 1, that is, if the document size detection function is disabled (S9: NO), the CPU 30a proceeds to step S15, which will be described later.

[0084] In step S11, the CPU 30a sets the size of the original 100 detected in the above-mentioned step S3 as the reading size by the image reading unit 12, and stores this as one of the setting data 556 described above (FIG. 16). Then, the CPU 30a advances the process to step S13.

[0085] In step S13, the CPU 30a updates the display of the operation screen, and if the operation screen is the copy operation screen 300, for example, updates the display of the character string 302a of the document size setting key 302 on the copy operation screen 300. Then, the CPU 30a advances the process to step S15.

[0086] In step S15, the CPU 30a determines whether an operation to instruct the ADF 14 to start feeding the original 100 has been accepted, and in the case of the copy function, for example, determines whether the start key 304 on the copy operation screen 300 has been operated (pressed). If an operation to instruct the ADF 14 to start feeding the original 100 has not been accepted (S15: NO), the CPU 30a returns the process to step S1. On the other hand, if an operation to instruct the ADF 14 to start feeding the original 100 has been accepted (S15: YES), the CPU 30a proceeds to step S17.

[0087] In step S17, the CPU 30a starts executing an original feeding task for controlling the feeding operation of the original 100 by the ADF 14. This starts the feeding operation of the original 100 by the ADF 14. Note that a detailed description of the original feeding task, including illustrations, will be omitted. With the execution of step S17, the CPU 30a ends the original size setting control task.

[0088] As described above, according to the first embodiment, when the guide width D transitions from a state in which it is adjusted to the width dimension W of the original 100 to a state in which it is wider than that, the original size detection function is enabled, that is, the size detected by the original size detection function is set as the size (read size) of the original 100. When the guide width D transitions from a wide state to a narrow state, the original size detection function is disabled, that is, updating of the size (read size) of the original 100 is prohibited. As a result, while enjoying the convenience of the original size detection function, the image of the original 100 can be read in its entirety by the image reading unit 12, and a read image without tilt can be obtained.

[0089] Note that the CPU 30a in the first embodiment, particularly the CPU 30a that executes steps S1 and S3 of the document size setting control task, is an example of a size detection means according to the present disclosure. The CPU 30a that executes the document size setting control task, particularly the CPU 30a that executes steps S1 to S15 of the document size setting control task, is an example of a setting control means according to the present disclosure, and steps S1 to S15 of the document size setting control task are an example of a size setting control process according to the present disclosure.

[0090] Furthermore, in the first embodiment, the copy function has been described as an example, but similar actions and effects can be achieved when the ADF 14 is used in an image scanner function and a fax function (fax transmission function).

[0091] [Second Example] Next, a second embodiment of the present disclosure will be described.

[0092] As described above, in the first embodiment, once the size (read size) of the original 100 is set by the original size detection function, this set size of the original 100 is cleared when the ADF 14 finishes feeding all of the originals 100 placed on the original tray 14a to the image reading position P of the image reading unit 12, or when all of the originals 100 placed on the original tray 14a are removed from the original tray 14a. In addition, in the second embodiment, after the size of the original 100 is set by the original size detection function, the set size of the original 100 is also cleared when a state in which no operation, including operation of the original guides 14c and 14c, is performed continues for a predetermined waiting time Tb. The waiting time Tb here is a time, for example, 5 seconds, slightly longer than the average time from when the size of the original 100 is set by the original size detection function to when an operation (e.g., operation of the start key 304) instructing the ADF 14 to start feeding the original 100 is performed. This waiting time Tb is an example of a predetermined time according to the present disclosure.

[0093] In the second embodiment, the CPU 30a also executes the document size setting control task, but the document size control task in the second embodiment includes steps S201 to S203 shown in Fig. 19 in addition to the document size setting control task in the first embodiment (Fig. 17). Steps S201 to S203 are provided between the case of NO in step S9 and step S15.

[0094] That is, if the document size update prohibition flag Fb is set to 1 in step S9, that is, if the document size detection function is disabled (S9: NO), the CPU 30a proceeds to step S201. Then, in step S201, the CPU 30a determines whether or not the standby time Tb has elapsed since the document size update prohibition flag Fb was set to 1, that is, since step S109 in the flag setting process described above (FIG. 18) was executed. Here, if the standby time Tb has elapsed since the document size update prohibition flag Fb was set to 1 (S201: YES), the CPU 30a proceeds to step S203. On the other hand, if the standby time Tb has not yet elapsed since the document size update prohibition flag Fb was set to 1 (S201: NO), the CPU 30a proceeds to step S15.

[0095] Thus, according to the second embodiment, even if the size of the original 100 is set by the original size detection function and no operation is performed for a predetermined waiting time Tb, the set size of the original 100 is canceled. This is useful when you want to change the size of the original 100 that has been set, especially when you want to change it to a size smaller than the set size of the original 100.

[0096] [Third Example] Next, a third embodiment of the present disclosure will be described.

[0097] According to the document size detection function in the first embodiment (and second embodiment) described above, the size of the document 100 is detected based on the document size detection table 200 shown in FIG. 7, that is, it is determined which standard size the size of the document 100 conforms to. However, according to the document size detection function in the second embodiment, the size of the document 100 is detected based on the document size detection table 200 shown in FIG. 20.

[0098] That is, according to the document size detection table 210 shown in FIG. 20 , the size of the document 100 is not detected as conforming to one of the standard sizes depending on the value of the guide width D. Rather, the size of the document 100 is linearly defined by the value of the guide width D itself, and more precisely, the width dimension W of the document 100 is defined. Specifically, for each standard size (see FIG. 6 ), a predetermined range based on the width dimension W is defined, for example, a range of ±5 mm. Then, only when the value of the guide width D falls within the predetermined range (±5 mm) based on the width dimension W of one of the standard sizes, is the size of the document 100 detected as conforming to that standard size. In other cases, the size of the document 100 is defined by the value of the guide width D itself. For example, if the guide width D is less than 153 mm and both the first and second detection pieces 14f and 14g are in the OFF state, the size of the document 100 is detected as A5R. When the guide width D is equal to or greater than 153 mm and less than 177 mm, and the first and second detection pieces 14f and 14g are both in the OFF state, the width W of the document 100 is determined by the value of the guide width D itself.

[0099] More specifically, as shown in the left diagram of Fig. 21A, suppose that an A5R document 100 is placed on document tray 14a of ADF 14 and document guides 14c and 14c are aligned with both side edges of document 100. In this case, the size of document 100 is detected as A5R. Then, as shown in the right diagram of Fig. 21A, the detected size A5R is represented by character string 302a of document size setting key 302.

[0100] Here, suppose that, with the intention of widening the scanning size of image scanning unit 12 in the width direction, document guides 14c and 14c are moved in the direction in which guide width D is widened, as shown in the left diagram of FIG. 21B, particularly as indicated by arrows 450 and 450 in the left diagram of FIG. 21B, to a position where guide width D is 164 mm. In this case, the size of document 100 is not detected as conforming to any standard size, but rather the width dimension W of document 100 is determined by the value of guide width D, i.e., 164 mm. Then, as shown in the right diagram of FIG. 21B, the value of guide width D, i.e., 164 mm, is represented by character string 302a of document size setting key 302.

[0101] Furthermore, as shown in the left diagram of Fig. 21C, and particularly as indicated by arrows 460 and 460 in the left diagram of Fig. 21C, it is assumed that document guides 14c and 14c are again aligned with both side edges of document 100. In this case, as in the first embodiment (and second embodiment) described above, the detected size of document 100, i.e., the width dimension W of document 100 of 164 mm, is maintained, that is, remains unchanged. Then, as shown in the right diagram of Fig. 21C, character string 302a of document size setting key 302 also remains in the state indicating the detected size of 164 mm.

[0102] As a result, while the width W of the original 100 is 148 mm as shown in Fig. 22A, the width W of the read image becomes 164 mm as shown in Fig. 22B, that is, the width W of the read image is widened. Note that the length L of the read image is the same as the length L of the original 100, as in the first embodiment (and the second embodiment).

[0103] Thus, according to the third embodiment, only when the value of guide width D falls within a predetermined range based on the width dimension W of one of the standard sizes, the size of the original 100 is detected as conforming to that standard size, and in other cases, the size of the original 100 is determined by the value of guide width D itself. This is useful when, as described with reference to Fig. 21, it is desired to intentionally widen the reading size in the width direction by the image reading unit 12.

[0104] In the third embodiment, as in the first embodiment, the size (or width dimension W) of the original 100 set by the original size detection function is cleared when the ADF 14 has finished feeding all of the originals 100 placed on the original tray 14a to the image reading position P of the image reading unit 12, or when all of the originals 100 placed on the original tray 14a have been removed from the original tray 14a. Also, as in the second embodiment, the set size of the original 100 may be cleared when a state in which no operation is performed continues for a predetermined waiting time Tb after the size of the original 100 has been set by the original size detection function.

[0105] [Fourth Example] Next, a fourth embodiment of the present disclosure will be described.

[0106] In the fourth embodiment, when the document 100 is placed on the document tray 14a of the ADF 14, the document guides 14c and 14c are aligned with both side edges of the document 100, and then the document guides 14c and 14c are moved in a direction widening the guide width D by a distance equal to or greater than a predetermined threshold Dth. The crop scan mode is a mode in which an image of the document 100 is read at a size larger than the document 100, a portion corresponding to the image of the document 100 is cropped from the read image, and the tilt of the cropped image is corrected. The predetermined threshold Dth is, for example, 20 mm. In the crop scan mode, the image of the document 100 is cropped and the tilt of the cropped image is corrected by the image processing unit 50. The tilt correction of the cropped image is performed using the detection results of the tilt sensors 14v and 14v.

[0107] Specifically, as shown in the left diagram of FIG. 23A, assume that an irregular-sized document 100 having a width W of 164 mm is placed on document tray 14a of ADF 14, and document guides 14c and 14c are aligned with both side edges of document 100. If the document size detection function detects the size of document 100 based on document size detection table 200 shown in FIG. 7, the detected size by the document size detection function will be A5R. As shown in the right diagram of FIG. 23A, the detected size A5R is represented by character string 302a of document size setting key 302. It should be noted that the length L of document 100 is, for example, 220 mm.

[0108] In this state, as shown in the left diagram of FIG. 23B, and particularly as indicated by arrows 470 and 470 in the left diagram of FIG. 23B, the document guides 14c and 14c are moved by more than the threshold value Dth in the direction in which the guide width D is widened, for example, to a position corresponding to B5R. As a result, the document size detected by the document size detection function becomes B5R. Then, as shown in the right diagram of FIG. 23B, the detected size B5R is represented by the character string 302a of the document size setting key 302.

[0109] At the same time, crop scan mode is set. To indicate this, as shown in FIG. 23, an appropriate indicator 320 is displayed at an appropriate position on the copy operation screen 300, for example, in the upper left corner of the copy operation screen 300. The display of this indicator 320 allows the user to intuitively recognize that crop scan mode has been set. The indicator 320 is an example of predetermined information according to the present disclosure. The copy operation screen 300 including the indicator 320 is displayed under the control of the CPU 30a. The CPU 30a, which controls the display of the copy operation screen 300 including the indicator 320, cooperates with the display 22b to constitute an example of information output means according to the present disclosure. Furthermore, in addition to or instead of the display of the indicator 320, the fact that crop scan mode has been set may be output by voice.

[0110] Even when copying is performed with this crop scan mode set, the image of the original 100 is read in its entirety by the image reading unit 12, and a read image without tilt can be obtained. Moreover, the convenience of the original size detection function can be enjoyed.

[0111] Specifically, as shown in FIG. 24A, the width W of the original 100 is 164 mm, whereas the detected size by the original size detection function is B5R as shown in FIG. 24B. That is, the width W of the detected size is 182 mm, which is larger than the width W of the original 100. Therefore, by setting the detected size by the original size detection function as the size (read size) of the original 100, the image of the original 100 is read in its entirety by the image reading unit 12. However, because both side edges of the original 100 are not constrained by the original guides 14c, the original 100 may tilt as it is transported. However, even if the original 100 is tilted, the crop scan mode cuts out the image of the original 100 from the read image and corrects the tilt of the cut-out image. Therefore, the corrected image, or what is called a crop scan image, is obtained as shown in FIG. 24C, i.e., an image without any gaps or tilt. Similarly, as shown in FIG. 24D, the image on the printed matter is an ideal image with no missing parts or tilts.

[0112] As shown in the left diagram of FIG. 25A, when the document guides 14c and 14c are realigned with the side edges of the document 100, as indicated by the arrows 480 and 480 in the left diagram of FIG. 25A, the crop scan mode is canceled. This causes the aforementioned indicator 320 to disappear from the copy operation screen 300, as shown in FIG. 25B. Meanwhile, the detected size by the document size detection function remains unchanged, i.e., B5R, as in the first embodiment. Therefore, as shown in the right diagram of FIG. 25A, the character string 302a of the document size setting key 302 also remains unchanged, indicating the detected size of B5R. Therefore, even when copying is performed in this state, a printed image without any missing or tilted images is obtained.

[0113] The CPU 30a in the fourth embodiment executes a crop scan mode setting control task in accordance with a crop scan mode setting control program (not shown) included in the control program described above. The flow of this crop scan mode setting control task is shown in FIG. 26. The CPU 30a executes the crop scan mode setting control task when (one or more) documents 100 are placed on the document tray 14a, that is, when this is detected by the document placement sensor 14X. When the crop scan mode setting control task is executed, a storage area (not shown) for temporarily storing (storing) a saved guide width Ds (described later) is cleared. This storage area is provided, for example, in the RAM of the main memory unit 30b.

[0114] According to this crop scan mode setting control task, first, in step S201, the CPU 30a acquires guide width information indicating the guide width D from the guide width detection unit 14e, and acquires document detection piece information indicating the states of the document detection pieces 14f and 14g from the document length sensors 14h and 14i. Then, the CPU 30a proceeds to step S203.

[0115] In step S203, the CPU 30a determines whether the saved guide width Ds is saved in the aforementioned saving area. If the saved guide width Ds is saved (S203: YES), the CPU 30a proceeds to step S205. On the other hand, if the saved guide width Ds is not saved (S203: NO), the CPU 30a proceeds to step S209, which will be described later.

[0116] In step S205, the CPU 30a determines whether the value (Dp-Ds) obtained by subtracting the saved guide width Ds from the current guide width Dp is equal to or greater than the threshold value Dth, i.e., whether the guide width D has been increased to equal to or greater than the threshold value Dth. If the guide width D has been increased to equal to or greater than the threshold value Dth (S205: YES), the CPU 30a proceeds to step S207. On the other hand, if the guide width D has not been increased to equal to or greater than the threshold value Dth (S205: NO), the CPU 30a proceeds to step S209, which will be described later.

[0117] In step S207, the CPU 30a sets the crop scan mode, and then the CPU 30a advances the process to step S208.

[0118] In step S209, based on the information acquired in step S201, that is, by comparing the information acquired in step S2011 with the document size detection table 200 described above (FIG. 7), the size of the document 100 is detected. Then, the CPU 30a advances the process to step S211.

[0119] In step S211, the CPU 30a determines whether the size of the original 100 remains unchanged over the aforementioned confirmation time Ta, more specifically, whether the size of the original 100 detected in step S209 remains unchanged. If the size of the original 100 remains unchanged over the confirmation time Ta (S211: YES), the CPU 30a proceeds to step S213. On the other hand, if the size of the original 100 does not remain unchanged over the confirmation time Ta (S211: NO), the CPU 30a returns the process to step S201.

[0120] In step S213, the CPU 30a sets the size of the original 100 detected in the above-mentioned step S209 as the reading size by the image reading unit 12, and stores this as one of the setting data 556 described above (FIG. 16). Then, the CPU 30a advances the process to step S215.

[0121] In step S215, the CPU 30a updates the display of the operation screen, and if the operation screen is the copy operation screen 300, for example, updates the display of the character string 302a of the document size setting key 302 and the display of the indicator 320 on the copy operation screen 300. Then, the CPU 30a advances the process to step S217.

[0122] In step S217, the CPU 30a stores the guide width D corresponding to the width dimension W of the document 100 as the stored guide width Ds in the storage area, and stores the minimum value of the guide width D as the stored guide width Ds in the storage area. Strictly speaking, the minimum value of the guide width D related to the size of the document 100 set in the above-mentioned step S213 (i.e., the basis for the size) is stored as the stored guide width Ds. Then, the CPU 30a proceeds to step S219.

[0123] In step S219, the CPU 30a determines whether an operation to instruct the ADF 14 to start feeding the original 100 has been accepted, and in the case of the copy function, for example, determines whether the start key 304 on the copy operation screen 300 has been operated. If an operation to instruct the ADF 14 to start feeding the original 100 has not been accepted (S219: NO), the CPU 30a returns the process to step S201. On the other hand, if an operation to instruct the ADF 14 to start feeding the original 100 has been accepted (S219: YES), the CPU 30a proceeds to step S221.

[0124] In step S221, the CPU 30a starts the execution of an original feeding task for controlling the feeding operation of the original 100 by the ADF 14. This starts the feeding operation of the original 100 by the ADF 14. With this, the CPU 30a ends the crop scan mode setting control task.

[0125] Although not shown in Figure 26, if the guide width D narrows after the crop scan mode is set, more specifically if the current guide width Dp narrows to near the saved guide width Ds (i.e., greater than the threshold value Dth), the crop scan mode is canceled.

[0126] As described above, according to the fourth embodiment, when the document 100 is placed on the document tray 14a of the ADF 14, the document guides 14c and 14c are aligned with both side edges of the document 100, and then the document guides 14c and 14c are moved by more than the predetermined threshold value Dth in the direction widening the guide width D, the crop scan mode is set. Then, by performing copying with the crop scan mode set, the image of the document 100 is read in its entirety by the image reading unit 12, and a read image without tilt can be obtained. Furthermore, the convenience of the document size detection function can be enjoyed. That is, while enjoying the convenience of the document size detection function, the image of the document 100 can be read in its entirety by the image reading unit 12, and a read image without tilt can be obtained.

[0127] Note that the CPU 30a in the fourth embodiment, and in particular the CPU 30a that executes steps S201 to S219 of the crop scan mode setting control task, is also an example of a setting control means according to the present disclosure. Steps S201 to S219 of the crop scan mode setting control task are also an example of a crop scan mode setting control process according to the present disclosure.

[0128] In the fourth embodiment, as described with reference to FIG. 23 , when the guide width D is increased to or greater than the threshold value Dth, the crop scan mode is set and the size (read size) of the original 100 is set. As in the first embodiment, the set size of the original 100 is cleared when the ADF 14 finishes feeding all of the originals 100 placed on the original tray 14a or when all of the originals 100 placed on the original tray 14a are removed from the original tray 14a. In addition, as in the second embodiment, the set size of the original 100 may be cleared when no operation is performed for a predetermined waiting time Tb after the size of the original 100 is set. Furthermore, as in the conventional technology, the set size of the original 100 may be cleared when the guide width D is changed. In other words, each time the guide width D is changed, the size of the original 100 corresponding to the new guide width D may be set. Furthermore, similarly to the third embodiment, depending on the value of the guide width D, the width dimension W of the document 100 may be defined (linearly defined) by the value of the guide width D itself.

[0129] [Other application examples] The above-described examples are specific examples of the present disclosure and do not limit the technical scope of the present disclosure. The present disclosure can also be applied to aspects other than these examples.

[0130] For example, a CPU may be provided in the ADF 14, and the CPU of the ADF 14 may execute a document size setting control task or a crop scan mode setting control task. Furthermore, standard sizes other than the eight standard sizes shown in FIG. 6 may also be detectable by the document size detection function.

[0131] In each embodiment, the present disclosure is applied to a multifunction peripheral as the image forming apparatus 10, but is not limited to this. That is, the present disclosure can also be applied to a dedicated copier, dedicated image scanner, dedicated fax machine, etc., that is, to the ADF in these dedicated machines.

[0132] In addition, the present disclosure is not limited to the form of the document feeder ADF 14, but can also be provided in the form of a program, i.e., a control program for the document feeder, and in the form of a method, i.e., a control method for the document feeder.

[0133] In addition, the present disclosure can also be provided in the form of a computer-readable recording medium on which a control program for a document feeder is recorded. Examples of recording media include semiconductor media such as SD memory cards and USB memory, and disc media such as CDs and DVDs. These portable storage media are not the only examples; built-in (internal) storage media such as ROMs and hard disk drives can also be used as recording media. [Explanation of symbols]

[0134] 10... Image forming device 12... Image reading unit 14 … ADF 14a ... Document tray 14c … Manuscript Guide 14e ... Guide width detection unit 14f, 14g ... Document detection piece 14h, 14i ... Document length sensor 14x... Document placement sensor 22 ... Operation unit 22a ... Touch panel 22b … Display 30...Control section 30a...CPU30a 30b... Main memory section Dth: threshold

Claims

1. A document feeder including a document placement unit on which a sheet-like document is placed, the document placement unit feeding the document placed on the document placement unit to an image reading position for reading an image of the document by an image reading unit, a regulating member for regulating the positions of both side edges of the document in a width direction that is perpendicular to a feed direction of the document placed on the document placement section and along both main surfaces of the document; a size detection unit that detects the size of the document based on the position of the regulating member; and The document feeder further comprises a setting control unit that performs a predetermined process including setting a size of the document based on a transition state of the position of the regulating member.

2. 2. The document feeding device of claim 1, wherein the predetermined processing includes a size setting control processing for setting the size of the document in accordance with the detection result by the size detection means when the position of the regulating member is moved from a position corresponding to the actual size of the document to a position corresponding to a size larger than the actual size of the document, and then leaving the set size of the document unchanged when the position of the regulating member is moved to a position corresponding to a size smaller than the larger size.

3. 3. The document feeding device according to claim 2, wherein the setting control means sets the size of the document in accordance with the movement of the position of the regulating member from a position corresponding to the actual size of the document to a position corresponding to the larger size during the size setting control process, and when a predetermined time has elapsed since the size of the document was set, the setting control means does not leave the set size of the document unchanged, but sets the size of the document in accordance with the detection result by the size detection means.

4. 3. The document feeding device according to claim 2, wherein the setting control means, when the detection result by the size detection means conforms to a standard size conforming to a predetermined standard, sets the conforming standard size as the size of the document in accordance with the detection result by the size detection means, and when the detection result by the size detection means does not conform to a standard size conforming to the predetermined standard, sets a dimension corresponding to the position of the regulating member as the dimension of the document in at least the width direction.

5. 2. The document feeding device according to claim 1, wherein the predetermined processing includes a crop scan mode setting control processing for, when the position of the regulating member is moved from a position corresponding to the actual size of the document to a position corresponding to a size larger than the actual size of the document, setting the size of the document in accordance with the detection result by the size detection means, and also setting a crop scan mode in which a portion corresponding to the image of the document is cut out from the read image read by the image reading means and an inclination of the cut-out image is corrected.

6. 6. The document feeding device according to claim 5, wherein the setting control means performs the crop scan mode setting process when the position of the regulating member is moved from a position corresponding to the actual size of the document to a position corresponding to a size that is larger than the actual size of the document by a predetermined threshold or more.

7. 6. The document feeder according to claim 5, further comprising an information output unit which, when the crop scan mode is set, outputs predetermined information indicating that the crop scan mode has been set.

8. A document feeder according to any one of claims 1 to 7, and An original reading device comprising the image reading means.

9. 1. A control program for controlling a document feeder having a document placement section on which a sheet-like document is placed, the document feeder feeding the document placed on the document placement section to an image reading position by an image reading unit for reading an image of the document, the control program comprising: The document feeder further includes a regulating member for regulating the positions of both side edges of the document in a width direction that is perpendicular to a feed direction of the document placed on the document placement section and along both main surfaces of the document, and a size detection step of detecting a size of the document based on a position of the regulating member; and A control program that causes a computer to execute a setting control procedure for performing a predetermined process including setting the size of the document based on the transition of the position of the regulating member.

10. 1. A method for controlling an original feeding device, comprising: a placement section on which a sheet-like original is placed; and feeding the original placed on the placement section to an image reading position by an image reading means for reading an image of the original, the method comprising: The document feeder further includes a regulating member for regulating the positions of both side edges of the document in a width direction that is perpendicular to a feed direction of the document placed on the document placement section and along both main surfaces of the document, and a size detection step of detecting a size of the document based on a position of the regulating member; and A control method comprising: a setting control step of performing a predetermined process including setting a size of the document based on a transition state of the position of the regulating member.

Images