Reading device, reading device control method, and reading device control program

Abstract

To solve a problem in which: when a system is employed which takes a position separated by a predetermined distance from a reference position of a device body as a reading position, an attitude of a document changes due to positional deviation and the like when a sheet material is attached to glass, which may prevent accurate reading of the document.SOLUTION: A scanner 1 comprises: a second glass member 16; a body frame 12; a sheet member 26; a document conveying unit 46; a reading unit 20; and a control unit 30. The sheet member 26 is arranged on the second glass member 16. The document conveying unit 46 conveys a document G so that the document G comes into contact with the second glass member 16 at a position H and the document G comes into contact with the second glass member 16 at a position C. The reading unit 20 reads the document G at a position F that is between a first position and a second position where the document G is not in contact with the sheet member 26 and the second glass member 16. The control unit 30 specifies the position F according to the position of the sheet member 26 detected by the reading unit 20.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a reading device, a control method for a reading device, and a control program for a reading device. [Background technology]

[0002] The image reading device of Patent Document 1 includes a sheet material that forms a gap between the document and the first document glass so that the document conveyed by the document conveying device does not come into contact with the first document glass.Then, the document in a non-contact state is read by the reading unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-11650 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the image reading device of Patent Document 1, if a method is adopted in which the reading position is a position a predetermined distance away from the reference position of the device body, the posture of the document in contact with the sheet material may change due to a misalignment of the sheet material attached to the glass, and the distance between the document and the glass at the reading position may change, which may result in the document not being read accurately. [Means for solving the problem]

[0005] In order to solve the above problem, the reading device of the present invention comprises a transparent member, a frame surrounding the transparent member, a plate-shaped member placed on the transparent member, a transport unit that transports the original so that the original contacts the transparent member at a first position in the transport direction of the original and contacts the plate-shaped member at a second position in the transport direction, a reading unit that is movable in a movement direction along the transport direction relative to the transparent member and reads the original, and a control unit that controls the movement and reading operation of the reading unit, wherein the reading unit reads the original transported by the transport unit at a third position between the first position and the second position in the movement direction, where the original does not contact the plate-shaped member or the transparent member, and the control unit identifies the third position according to the position of the plate-shaped member detected by the reading unit.

[0006] In order to solve the above problem, the control method of the present invention for a reading device includes a transparent member, a frame surrounding the transparent member, a plate-shaped member placed on the transparent member, a transport unit that transports the document so that the document contacts the transparent member at a first position in the document transport direction and contacts the plate-shaped member at a second position in the document transport direction, a reading unit that is movable in a movement direction along the transport direction relative to the transparent member and reads the document at a reading position, and a control unit that controls the movement and reading operation of the reading unit, and is characterized by having the steps of: detecting the position of the plate-shaped member by reading the plate-shaped member while moving the reading unit; identifying the reading position based on the detected position of the plate-shaped member; and reading the document by the reading unit at the identified reading position.

[0007] In order to solve the above problem, the control program for a reading device of the present invention is a control program for a reading device comprising a transparent member, a frame surrounding the transparent member, a plate-shaped member placed on the transparent member, a transport unit that transports the document so that the document contacts the transparent member at a first position in the document transport direction and so that the document contacts the plate-shaped member at a second position in the document transport direction, a reading unit that is movable in a movement direction along the transport direction relative to the transparent member and reads the document at a reading position, and a control unit that controls the movement and reading operation of the reading unit, and is characterized in that the program causes a computer to execute the steps of detecting the position of the plate-shaped member by reading the plate-shaped member while moving the reading unit, identifying the reading position based on the detected position of the plate-shaped member, and reading the document by the reading unit at the identified reading position. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating the configuration of a scanner according to a first embodiment. [Figure 2] FIG. 2 is a block diagram of the scanner according to the first embodiment. [Figure 3] FIG. 2 is a plan view schematically showing the arrangement of a sheet member and a reading unit in the scanner of the first embodiment. [Figure 4] FIG. 2 is a partial vertical cross-sectional view showing the reading position and the surrounding area of ​​the reading position in the scanner of the first embodiment. [Figure 5] 5A to 5C are schematic diagrams showing positions in the Y direction in the scanner of the first embodiment. [Figure 6] 5A and 5B are schematic diagrams showing the detection results of the edge of a sheet member read by the scanner of the first embodiment. [Figure 7] 5A to 5C are schematic diagrams showing different sizes of areas read by the scanner of the first embodiment. [Figure 8] 5 is a flowchart showing the flow of each process executed in the scanner of the first embodiment. [Figure 9]10 is a flowchart showing the flow of each process executed in the scanner of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be briefly described below. A reading device according to a first aspect includes a transparent member, a frame surrounding the transparent member, a plate-like member placed on the transparent member, a transport unit that transports the document so that the document contacts the transparent member at a first position in the document transport direction and so that the document contacts the plate-like member at a second position in the document transport direction, a reading unit that is movable in a movement direction along the transport direction relative to the transparent member and reads the document, and a control unit that controls the movement and reading operation of the reading unit, wherein the reading unit reads the document transported by the transport unit at a third position between the first position and the second position in the movement direction, where the document does not contact the plate-like member or the transparent member, and the control unit identifies the third position according to the position of the plate-like member detected by the reading unit. According to this aspect, the third position, which is the reading position, is identified according to the detected position of the plate-like member. Here, even if the plate-like member is misaligned, the third position is maintained at a substantially constant distance from the plate-like member, so that the distance between the document and the transparent member at the reading position is maintained, allowing the document to be read accurately.

[0010] The reading device of the second aspect is characterized in that, in the first aspect, the control unit detects the position of the plate-like member based on data obtained from the reading unit, the data being of a second size whose width direction perpendicular to the movement direction is smaller than the first size, and the first size is the largest size among the sizes in which the reading unit can read the original. According to this aspect, the position of the plate-like member is detected based on the second size that is relatively smaller than the first size, so that the speed of the process required to detect the plate-like member can be increased.

[0011] The reading device of the third aspect is characterized in that, in the second aspect, the control unit causes the reading unit to perform reading for shading correction and reading for detecting the position of the plate-like member while the reading unit is moving, and in the width direction, the reading size for the shading correction is larger than the reading size for detecting the position of the plate-like member. According to this aspect, the third position can be identified using the result of the shading correction, and therefore the third position can be identified with high accuracy.

[0012] The reading device of the fourth aspect is characterized in that, in the second or third aspect, the frame is provided with a reference member for identifying the position of the reading unit in the movement direction, and the control unit detects the position of the plate-like member based on data of the position where it overlaps with the reference member in the width direction. According to this aspect, the position of the plate-like member is detected based on data on the position where it overlaps with the reference member, so even if the reading unit is tilted with respect to the width direction, variation in the reading position in the movement direction due to the tilt of the reading unit can be reduced, thereby making it possible to identify the third position with high accuracy.

[0013] The reading device of the fifth aspect is characterized in that, in the fourth aspect, the frame is provided with an axis that is along the movement direction and guides the reading unit while it is moving, and the control unit detects the position of the plate-like member based on data of the position that overlaps with the axis in the width direction. According to this aspect, the reference member can be positioned close to the axis where the amount of tilt of the reading unit relative to the width direction is relatively small, thereby reducing the influence of the tilt of the reading unit during reading and enabling the third position to be determined with high accuracy.

[0014] The reading device of the sixth aspect is characterized in that, in any one of the first to fifth aspects, the control unit reads the original in either a first mode or a second mode in which the resolutions in the conveying direction are different from each other, and the third position in the first mode and the third position in the second mode are set to the same position. According to this aspect, it is not necessary to perform the process for setting the third position in each of the first mode and the second mode, and therefore the process time for setting the third position can be shortened.

[0015] The reading device of the seventh aspect is characterized in that, in any one of the first to fifth aspects, the control unit reads the original in either a first mode or a second mode in which the resolution in the conveying direction is different from each other, and the third position in the first mode and the third position in the second mode are set to different positions. According to this aspect, the third position can be set to a position suitable for the resolution of each of the first mode and the second mode.

[0016] The reading device of the eighth aspect is any one of the first to seventh aspects, characterized in that the conveying section has a background member in a position opposite the transparent member, and the color of the background member is different from the color of the plate-shaped member. According to this aspect, the color of the plate-like member is different from the color of the background member, which makes it easier to optically detect the plate-like member.

[0017] A reading device according to a ninth aspect is characterized in that, in any one of the first to eighth aspects, the plate-shaped member is fixed to the transparent member by an adhesive layer, and the adhesive layer is not provided between the edge of the plate-shaped member that is closer to the second position and the transparent member. According to this aspect, when the plate-shaped member is fixed to the transparent member via the adhesive layer, even if the adhesive layer protrudes outward from the fixing target area inside the plate-shaped member, the adhesive layer is held in the space where the adhesive layer is not provided, thereby preventing the adhesive layer from protruding outward from the edge of the plate-shaped member, thereby preventing a decrease in the detection accuracy of the position of the plate-shaped member.

[0018] A reading device according to a tenth aspect is the ninth aspect which recites the eighth aspect, characterized in that the color of the adhesive layer is different from the color of the background member. According to this aspect, even if the adhesive layer reaches the edge of the plate-shaped member, the color of the adhesive layer is different from the color of the background member, thereby reducing the possibility of mistakenly detecting the plate-shaped member as the background member.

[0019] The reading device of the 11th aspect is any one of the first to tenth aspects, characterized in that the control unit changes the third position depending on the number of sheets of the original document transported by the transport unit. It is predicted that the more the number of documents transported by the transport unit increases, the more wear on the plate-shaped member will progress. Here, according to this aspect, even if the plate-shaped member is worn, the third position, which is the reading position, can be corrected based on the plate-shaped member by changing the third position according to the number of documents, so that the document can be read at an optimal position.

[0020] The reading device of the 12th aspect is characterized in that, in any one of the first to 11th aspects, when the number of sheets of the original document transported by the transport unit exceeds a predetermined number, the control unit causes the reading unit to read the plate-like member, and detects wear of the plate-like member according to the detected position of the plate-like member. According to this aspect, the wear state of the plate-shaped member can be detected, and therefore replacement of the plate-shaped member can be promoted.

[0021] A control method for a reading device according to a thirteenth aspect is a control method for a reading device comprising a transparent member, a frame surrounding the transparent member, a plate-shaped member arranged on the transparent member, a transport unit that transports the document so that the document contacts the transparent member at a first position in the document transport direction and so that the document contacts the plate-shaped member at a second position in the document transport direction, a reading unit that is movable relative to the transparent member in a movement direction along the transport direction and reads the document at a reading position, and a control unit that controls the movement and reading operation of the reading unit, and is characterized by having the steps of: detecting the position of the plate-shaped member by reading the plate-shaped member while moving the reading unit; identifying the reading position based on the detected position of the plate-shaped member; and reading the document by the reading unit at the identified reading position. According to this aspect, it is possible to obtain the same functions and effects as the reading device according to the first aspect.

[0022] A control program for a reading device according to a fourteenth aspect is a control program for a reading device comprising: a transparent member; a frame surrounding the transparent member; a plate-shaped member arranged on the transparent member; a transport unit that transports the document so that the document contacts the transparent member at a first position in the document transport direction and so that the document contacts the plate-shaped member at a second position in the document transport direction; a reading unit that is movable relative to the transparent member in a movement direction along the transport direction and reads the document at a reading position; and a control unit that controls the movement and reading operation of the reading unit, and is characterized in that the program causes a computer to execute the steps of: detecting the position of the plate-shaped member by reading the plate-shaped member while moving the reading unit; identifying the reading position based on the detected position of the plate-shaped member; and reading the document by the reading unit at the identified reading position. According to this aspect, it is possible to obtain the same functions and effects as the reading device according to the first aspect.

[0023] Hereinafter, first and second embodiments, which are examples of a reading device, a control method for a reading device, and a control program for a reading device according to the present invention, will be specifically described.

[0024] [Embodiment 1] FIG. 1 shows a scanner 1, which is an example of a reading device. The scanner 1 includes an image reading device 10 that reads information on a document G, and an automatic conveying device 40 that is disposed above the image reading device 10. The scanner 1 reads information on a document G placed on the image reading device 10 or a document G conveyed by the automatic conveying device 40.

[0025] In the XYZ coordinate system shown in each figure, the X direction is the depth direction of the device, the Y direction is the width direction of the device, and the Z direction is the height direction of the device. The X direction, Y direction, and Z direction are perpendicular to each other. The X direction is an example of the width direction of the document G. When viewing the scanner 1 from the front, if the left and right are distinguished from the center in the device width direction, the left is the -Y direction and the right is the +Y direction. If the front and back are distinguished from the center in the device depth direction, the front is the +X direction and the back is the -X direction. If the top and bottom are distinguished from the center in the device height direction, the top is the +Z direction and the bottom is the -Z direction. In the following explanation, the +Z direction may be referred to as the top and the -Z direction as the bottom.

[0026] The automatic transport device 40 is composed of an original tray 42 on which multiple originals G are set, an output tray 44 on which the originals G are output after information has been read at the reading position, and an original transport section 46 that transports the originals G from the original tray 42 to the output tray 44. Automatic conveying device 40 feeds originals G one by one to the reading area. Automatic conveying device 40 is connected to image reading device 10 so as to be able to open and close, with the end of image reading device 10 in the -X direction serving as a pivot point. When automatic conveying device 40 is in the open position, first glass member 14 and second glass member 16, which will be described later, are opened.

[0027] In the following description, the position on second glass member 16 where information on document G being conveyed is read will be simply referred to as the reading position. A transport path T along which the document G is transported by the document transport unit 46 is formed inside the automatic transport device 40. The transport path T is formed in a C-shape from the document tray 42 to the discharge tray 44 when viewed from the +X direction to the -X direction.

[0028] Document transport unit 46 is an example of a transport unit, and transports document G so that document G comes into contact with second glass member 16 (described later) at position H (FIG. 5) in the transport direction of document G, and comes into contact with sheet member 26 (described later) at position C (FIG. 5) in the transport direction. Document transport unit 46 also includes a plurality of transport roller pairs 48, and a pressing member 56 (FIG. 4) that suppresses the floating of document G during reading.

[0029] Of the transport roller pairs 48 located upstream in the transport direction from the reading position of the document G on the transport path T, the one closest to the reading position is referred to as the first transport roller pair 52. Furthermore, of the transport roller pairs 48 located downstream in the transport direction from the reading position of the document G on the transport path T, the one closest to the reading position is referred to as the second transport roller pair 54. The first transport roller pair 52 and the second transport roller pair 54 each have a rotation axis along the X direction and are rotated by a motor (not shown).

[0030] The image reading device 10 includes a main body frame 12, a first glass member 14, an intermediate portion 15 (FIG. 4), a second glass member 16, a guide shaft 18, a support frame 19, a reading portion 20, a drive portion 24 (FIG. 2), a sheet member 26, an origin member 28 (FIG. 3), and a control portion 30 (FIG. 2).

[0031] The main body frame 12 is an example of a frame, and surrounds a second glass member 16 (described later) in the X and Y directions. The main body frame 12 also has a housing 12A that forms the outer shell of the image reading device 10, and an internal frame 12B that forms the framework of the image reading device 10 inside the housing 12A.

[0032] First glass member 14 is a member on whose upper surface original G is placed. Second glass member 16 is disposed in the -Y direction relative to first glass member 14. Original G transported by automatic transport device 40 passes above second glass member 16. Intermediate section 15 is located between first glass member 14 and second glass member 16.

[0033] The guide shaft 18 is an example of an axis along the Y direction, which is the movement direction of the reading unit 20. The guide shaft 18 is a cylindrical member extending along the Y direction. Both ends of the guide shaft 18 in the Y direction are provided on the main body frame 12. The guide shaft 18 guides the moving reading unit 20 in the Y direction. The guide shaft 18 extends in the Y direction, passing through a position slightly offset in the -X direction from the center of the reading unit 20 in the X direction. The support frames 19 are provided on both ends of the inner frame 12B in the X direction relative to the guide shaft 18, and support both ends of the reading unit 20 in the X direction. The reading unit 20, the sheet member 26, the origin member 28, and the control unit 30 will be described in detail later.

[0034] As shown in FIG. 3, first glass member 14 is a platen on which original G is placed, and is large enough to accommodate the entire original G. First glass member 14 is, for example, a colorless, transparent, rectangular glass plate. The long side of first glass member 14 is aligned with the Y direction in which guide shaft 18 extends. First glass member 14 is supported by main body frame 12. Information on original G placed on first glass member 14 is read by reading unit 20 through first glass member 14.

[0035] Second glass member 16 is an example of a transparent member and is made of a colorless, transparent, rectangular glass plate. Second glass member 16 has upper surface 16A with which the transported document G temporarily comes into contact. The length of second glass member 16 in the Y direction is shorter than the length of document G in the Y direction. The length of second glass member 16 in the X direction is longer than the length of document G in the X direction. Second glass member 16 is surrounded and supported in the X and Y directions by main body frame 12. Information on document G, which faces second glass member 16 in the Z direction, is read through second glass member 16 by reading unit 20. In this embodiment, when an object illuminated with visible light is observed through a certain member, the "certain member" is referred to as a "transparent member" if the color and shape of the object can be correctly recognized.

[0036] 1, the reading unit 20 is formed in a rectangular shape with the dimension in the X direction longer than the dimension in the Y direction. The reading unit 20 is guided in the Y direction by a guide shaft 18. In this way, the reading unit 20 is movable in the Y direction, which is the movement direction along the transport direction of the document G. Reading unit 20 reads original G while remaining stationary relative to second glass member 16. Reading unit 20 also reads original G while being moved in the Y direction relative to first glass member 14. In other words, reading unit 20 is configured to be able to read information from either original G placed on first glass member 14 or original G passing over second glass member 16, depending on its position in the Y direction.

[0037] Reading unit 20 is disposed in the -Z direction relative to first glass member 14 and second glass member 16. Reading unit 20 is supported from below by support frame 19 via carriage 21. Reading unit 20 is configured, as an example, as an image sensor that performs reading using the CIS (Contact Image Sensor) method. The width of reading unit 20 in the X direction is large enough to enable reading of almost the entire first glass member 14 in the X direction.

[0038] The drive unit 24 (FIG. 2), for example, has a movement mechanism including a belt and pulleys (not shown), and a drive source including a stepping motor (not shown), etc. The drive unit 24 is configured so that the stepping motor moves the carriage 21 via the movement mechanism, thereby moving the reading unit 20 back and forth in the +Y direction and the −Y direction.

[0039] 2, the control unit 30, which functions as a computer, includes a CPU (Central Processing Unit) 32, a memory 34, a position detection unit 36, and storage and a timer (not shown). The control unit 30 controls the operations of the reading unit 20, the drive unit 24, and the document transport unit 46 based on information input to the control unit 30. The control of the operation of the scanner 1 by the control unit 30 will be described later.

[0040] The memory 34 is an example of a storage unit and stores various types of data. The memory 34 stores various types of data, including the program PR executed by the CPU 32. In other words, the memory 34 is an example of a recording medium that stores a computer-readable program PR. Other examples of recording media include a CD (Compact Disc), a DVD (Digital Versatile Disc), a Blu-ray Disc, and a USB (Universal Serial Bus) memory. Furthermore, the program PR can be developed in a portion of the memory 34. The program PR is a program for causing the CPU 32 to execute each step in the scanner 1, which will be described later.

[0041] The position detection unit 36 ​​detects the X-direction position and the Y-direction position of the end of the sheet member 26 in the +Y direction, which will be described later. Here, the X-direction position and the Y-direction position of the carriage 21 correspond to the X-direction position and the Y-direction position at which reading by the reading unit 20 is performed. Therefore, the position detection unit 36 ​​detects the position at which reading by the reading unit 20 is performed by detecting the position of the carriage 21. In other words, the position detection unit 36 ​​can detect the position of the +Y-direction end of the sheet member 26 by reading the sheet member 26 while the reading unit 20 is moving in the +Y direction. The position detection unit 36 ​​functions when the CPU 32 executes each step, which will be described later.

[0042] As shown in Fig. 3, sheet member 26 is formed in a rectangular shape with the dimension in the X direction longer than the dimension in the Y direction. Sheet member 26 is placed on second glass member 16. The length in the X direction of sheet member 26 is shorter than the length in the X direction of second glass member 16. The length in the Y direction of sheet member 26 is shorter than the length in the Y direction of second glass member 16. Sheet member 26 is fixed to second glass member 16 by adhesive layer 29 (Fig. 5). When sheet member 26 is fixed to upper surface 16A by adhesive layer 29, factors that cause variations in the positional accuracy of sheet member 26 include errors in component dimensions and errors in assembly.

[0043] As shown in Fig. 5, sheet member 26 is a member for forming a gap between second glass member 16 and original G so that a portion of original G upstream of the portion read by reading unit 20 (Fig. 1) does not come into contact with upper surface 16A of second glass member 16. The thickness of sheet member 26 in the Z direction is set, for example, between 0.1 mm and 0.7 mm, and is set to, for example, 0.5 mm. Note that in Fig. 5, the dimensions are shown at different ratios from the actual size in order to clarify the configuration of each part.

[0044] Both ends of the sheet member 26 in the X direction and both ends of the sheet member 26 in the Y direction are collectively referred to as edge portion 27. Of the edge portion 27, the portion closer to position C (FIG. 5) described below is referred to as edge portion 27A. Edge portion 27A is the portion of edge portion 27 located at the end in the +Y direction. No adhesive layer 29 is provided between edge 27A and second glass member 16. In other words, sheet member 26 is not adhered to second glass member 16 between position C, which is the end in the +Y direction, and position B, which is a preset distance away in the -Y direction, forming space V.

[0045] The sheet member 26 is preferably made of a material with high light transmittance. The sheet member 26 is also preferably made of a material with a low coefficient of friction so as not to impose an excessive load on the conveyance of the document G. Furthermore, the sheet member 26 may be earthed to prevent the sheet member 26 from becoming charged due to contact with the document G.

[0046] 3, origin member 28 is attached to main body frame 12 at a position in the -Y direction relative to second glass member 16 and in the -X direction relative to guide shaft 18. Origin member 28 is also attached to the underside of main body frame 12 in the -Z direction, and can be read by reading unit 20. Note that in FIG. 3, origin member 28 is shown as being transparent in the +Z direction in order to clearly show the arrangement of origin member 28. In this way, the origin member 28 is provided on the main body frame 12 as an example of a reference member. The origin member 28 is also used to identify the position in the Y direction, which is the movement direction of the reading unit 20. The origin member 28 is also used when determining the first pixel of the reading unit 20.

[0047] In scanner 1, the first pixel is located at the end in the -X direction and the end in the -Y direction of the area read by reading unit 20, so it is preferable to place origin member 28 in a location close to the first pixel. Furthermore, if origin member 28 is attached to main body frame 12 at the very end position in the -X direction, the attachment area becomes small, which may reduce the attachment strength of origin member 28. For this reason, origin member 28 is attached in a position in the -X direction relative to guide shaft 18 and in the +X direction from the end of second glass member 16 in the -X direction.

[0048] Here, positions P1, P2, P3, P4, and P5 are possible detection positions in the X direction when detecting the position of the sheet member 26. Note that positions P1, P2, P3, P4, and P5 are not points but tiny reading areas, as indicated by the dashed dotted lines, and are shown as elliptical regions. Positions P1, P2, P3, P4, and P5 are arranged in this order from the -X direction to the +X direction. Position P2 is located approximately midway between positions P1 and P3, and position P4 is located approximately midway between positions P3 and P5.

[0049] Position P1 is the position of the end of the sheet member 26 in the −X direction. Position P2 is a position of a portion displaced in the +X direction from the center of the origin member 28 in the X direction. Position P3 is a position shifted in the +X direction relative to guide shaft 18, and is approximately the center of second glass member 16 in the X direction. Position P4 is located in the +X direction from position P3 and in the −X direction from position P5, which will be described later. Position P5 is the position of the end of the sheet member 26 in the +X direction.

[0050] As an example, the reading unit 20 is moved in the +Y direction using position P2, where the origin member 28 is located, as the reference position in the X direction. Here, in the reading unit 20, there is a high possibility that the central axis CA extending in the main scanning direction will tilt in a direction that intersects with the X direction due to factors such as assembly errors and errors in movement in the Y direction, which is the sub-scanning direction. Furthermore, the tilt direction of the central axis CA is not constant in the +Y direction, and may change during movement in the +Y direction.

[0051] Because the central axis CA of the reading unit 20 is tilted with respect to the X direction, the amount of deviation of the reading position in the Y direction by the reading unit 20 increases toward the end of the reading unit 20 in the X direction. In other words, the amount of deviation of the reading position in the Y direction by the reading unit 20 is smallest at position P2, which is closest to the origin member 28. Therefore, in this embodiment, as an example, when detecting the position of the end of the sheet member 26 in the +Y direction, the position of the sheet member 26 is set based on the result of reading at position P2 in the X direction. By reading at position P2, the influence of each error included in the reading position is reduced.

[0052] As shown in FIG. 4, a pressing member 56 is provided at a position facing upper surface 16A of second glass member 16 in the Z direction and at a position in the +Y direction relative to sheet member . The pressing member 56 is an example of a background member. The color of the pressing member 56 is different from the color of the sheet member 26. The color of the adhesive layer 29 (FIG. 5) is different from the color of the pressing member 56. Here, in this embodiment, "two objects have different colors" means that when their respective colors are measured according to JIS Z8781-4, the ΔE* of both objects is 3 or more, and more preferably 8 or more.

[0053] FIG. 5 schematically shows the Y-direction positions of each part of the document G, second glass member 16, sheet member 26, and adhesive layer 29. Note that FIG. 5 is a schematic diagram, and the size of each part has been partially modified to clarify the relative positions. In other words, the dimensional ratios of each part and member shown in FIG. 5 differ from the actual ratios. FIG. 5 also schematically shows paper dust QA and sticky debris QB on second glass member 16. Paper dust QA and sticky debris QB are also shown enlarged and do not represent their actual ratios. For example, paper dust QA may fall around the edge in the +Y direction of sheet member 26. Sticky dust QB that falls from an image portion formed with ink or the like or is transferred from glue that was attached to document G may, for example, adhere to the periphery of position H where document G and second glass member 16 come into contact.

[0054] The following describes positions A to H in the Y direction. Positions A to H are arranged in this order. Note that positions A to H are not arranged at equal intervals. When correcting reference position E, which serves as the reference for the reading position, reading unit 20 (FIG. 1) reads from positions A to H. Position C at the end of the sheet member 26 in the +Y direction is an example of the second position. When position C is expressed as a variable in the Y direction, it is simply represented as Y. In this embodiment, position F, which is a preset distance β [mm] away from position C, is newly set as the reading position by the reading unit 20. In other words, position F corresponds to a position obtained by correcting the reference position E.

[0055] The position of the end of adhesive layer 29 in the +Y direction is defined as position B. Position B is located in the −Y direction relative to position C, as described above. The position where reading of the edge of the sheet member 26 starts is defined as position A. Position A is separated from position C by an offset S1. In this embodiment, as an example, S1=-3 mm. The reference position E is an initial position that is set in advance in the control unit 30 and is read by the reading unit 20. In other words, the reference position E is a reading position before correction.

[0056] Position F is, as described above, a corrected reading position that is corrected by reading the position of the edge of the sheet member 26. Position F is an example of a third position. Position F can be expressed using the variable Y as Y+β. The amount of deviation in the Y direction between reference position E and position F is defined as α1. Position F is a position between positions H and C, which will be described later, in the movement direction of the document G. Position F is also a position where the document G does not come into contact with the sheet member 26 and the second glass member 16. Here, at position F, the reading unit 20 reads the document G being transported by the document transport unit 46 (FIG. 1).

[0057] The range in which good reading is possible by the reading unit 20 relative to position F is defined as M [mm]. The position of the end of range M in the -Y direction is defined as position D. The position of the end of range M in the +Y direction is defined as position G. Position F is located at the midpoint between positions D and G. Position H where document G comes into contact with top surface 16A is an example of the first position. Here, position F is expressed as reference position E+α1=Y+β+S1. As an example, the position H is a position that is a set value away from the reference position E. In this embodiment, as an example, the position S2 corresponding to the position H is set to be the reading position + 1 mm.

[0058] The control unit 30 controls the movement of the reading unit 20 in the Y direction, the reading operation, etc. Here, each control by the control unit 30 will be described. The control unit 30 identifies the position F according to the position of the sheet member 26 in the Y direction detected by the reading unit 20.

[0059] As shown in FIG. 7, the control unit 30 detects the Y-direction position of the sheet member 26 (FIG. 3) based on data acquired from the reading unit 20, in which the size in the X-direction, which is the width direction perpendicular to the movement direction of the document G, is a second size SZ2 data smaller than the first size SZ1. The first size SZ1 is the largest size of the document G that the reading unit 20 can read.

[0060] As shown in FIG. 4, an opposing plate 17 that faces first glass member 14 is provided at a position in the +Z direction relative to first glass member 14. The opposing plate 17 is used for so-called shading correction, and is made of, for example, a white, gray, black, or other resin plate or a metal plate painted in white, gray, black, or other color. The control unit 30 (FIG. 2) generates correction data based on the difference between the read value when the reading unit 20 reads the counter plate 17 and the read value when the reading unit 20 reads the document G.

[0061] The control unit 30 controls the reading unit 20 to perform reading for shading correction and reading for detecting the position of the sheet member 26 in the Y direction while the reading unit 20 is moving. Note that in the X direction, the reading size for shading correction is larger than the reading size for detecting the position of the sheet member 26 in the Y direction. The control unit 30 detects the position of the sheet member 26 in the Y direction based on data on the position where the sheet member 26 overlaps with the origin member 28 (FIG. 3) in the X direction. Specifically, the position P2 (FIG. 3) read by the reading unit 20 corresponds to the position where the sheet member 26 overlaps with the origin member 28 in the Y direction.

[0062] The control unit 30 causes the reading unit 20 to read the document G in either a first mode or a second mode, which have different reading resolutions in the transport direction. As an example, the resolution is 600 dpi in the first mode and 300 dpi in the second mode. The selection of the first mode or the second mode is, for example, performed by the user. Here, the position F (FIG. 5) in the first mode and the position F in the second mode are set to the same position. In other words, the position F is constant regardless of the selection of the first mode or the second mode. The control unit 30 changes the position F in accordance with the number of originals G transported by the original transport unit 46. In other words, when the number of originals G exceeds a set number, it is assumed that the edge of the sheet member 26 is worn, and the control unit 30 redetects the position of the edge of the sheet member 26 and performs control to correct the position F.

[0063] 6 shows, as an example, a detection result when the sheet member 26 is read by the reading unit 20 in monochrome mode at 600 dpi x 600 dpi. As an example, there are 11 pixels in the X direction and 141 pixels in the Y direction. Note that part of the result in the Y direction is not shown. The result read by the reading unit 20 is binarized using a threshold value of 50.

[0064] The detection result for a one-pixel position is shown in one square cell. A square cell alone indicates that the detection result is below the threshold. A square cell with intersecting diagonal lines indicates that the detection result is above the threshold. In other words, a cell without a diagonal line indicates that the position is determined to be one where the sheet material 26 does not exist, and a cell with a diagonal line indicates that the position is determined to be one where the sheet material 26 exists.

[0065] NG means that there are squares below the threshold, and the position of the edge of the sheet material 26 cannot be identified. OK means that only squares higher than the threshold exist in succession up to the seventh square in the Y direction, and the position of the edge of the sheet material 26 can be identified. As an example, FIG. 6 shows that the third position in the Y direction from the start of reading is detected as the position of the edge of the sheet material 26 in the +Y direction. The Kth position in the +Y direction from the first detected position represents the corrected reading position.In Figure 6, it is estimated that foreign matter such as paper dust has been detected in the positions of the squares with diagonal lines that appear singly from the third position onwards in the +Y direction.

[0066] Next, the operation of the scanner 1 of the first embodiment will be described. FIG. 8 is a flowchart showing the flow of each process when correcting the reference position E to the position F by detecting the position C of the edge of the sheet member 26 in the +Y direction. 1 to 5, and individual drawing numbers will be omitted for the various parts and components that make up the scanner 1. Each process shown in Fig. 8 is performed by the CPU 32 reading, expanding, and executing the program PR from the memory 34.

[0067] In step S10, the CPU 32 moves the reading unit 20 to position A, using position P2 as a reference. Furthermore, assuming position A to be the 0th position of the variable Y in the +Y direction, it sets Y=0. Then, the process proceeds to step S12. In step S12, the CPU 32 reads 11 pixels in the +X direction using the reading unit 20, and determines whether the binarized values ​​from X1 to X11 are all 0. If all are 0 (S12: Yes), the process proceeds to step S14. If even one 1 appears (S12: No), the process proceeds to step S16.

[0068] In step S14, the CPU 32 detects the position of the sheet member 26 by reading the sheet member 26 while moving the reading unit 20 in the +Y direction. Specifically, the CPU 32 determines whether or not an OK result, in which 11 pixels in the +X direction are all 0, has been obtained seven times in a row in the +Y direction, i.e., for seven consecutive pixels. If the result is OK seven times in a row (S14: Yes), the process proceeds to step S20. If the result is NG even once out of the seven times (S14: No), it is determined that there is a problem with the measurement or the reading location, and the program PR is ended with NG. At this time, a display unit or speaker (not shown) may be used to notify the user that the result is NG.

[0069] In step S16, the CPU 32 determines whether the position corresponding to the variable Y has reached a position six pixels before the position H corresponding to the set value S2 described above. If the value of the variable Y is S2-6 (S16: Yes), since there is no OK location within the read area, it is determined that there is a problem with the measurement or with the read location, and the process ends with NG, and the program PR is terminated. At this time, a display unit or speaker (not shown) may be used to notify the user that the process has ended with NG. If the value of the variable Y is smaller than S2-6 (S16: No), the process proceeds to step S18.

[0070] In step S18, the CPU 32 counts up the value of the variable Y by one, and then proceeds to step S12. In step S20, the CPU 32 determines whether OK continues until the variable Y is greater than 100. If the variable Y is greater than 100 (S20: Yes), the process proceeds to step S22. If the variable Y is 100 or less (S20: No), the process determines that there is an abnormality in the reading area, concludes as NG end, and ends the program PR. At this time, the NG end may be notified using a display unit or speaker (not shown).

[0071] In step S22, the CPU 32 stores the value Y=Y-7 to set the 0th position as the edge position of the sheet member 26 in the +Y direction. The offset amount α1 in the Y direction of the corrected position F relative to the reference position E is expressed as α1=(Y+β)+S1 using the aforementioned β and the offset S1 at the start of inspection. The CPU 32 stores this value of α1 as the correction setting value. In other words, the corrected reading position is identified based on the detected position of the sheet member 26. Then, the process proceeds to step S24. In step S24, the CPU 32 places the reading unit 20 at the corrected position F and causes it to read the document G. That is, the reading unit 20 reads the document G at the specified reading position. Then, the CPU 32 causes the program PR to end normally.

[0072] As described above, according to the scanner 1 of the first embodiment, the position F serving as the reading position is identified in accordance with the detected position of the sheet member 26. Here, even if the sheet member 26 is misaligned with respect to the set mounting position, the position F is maintained at a substantially constant distance from the sheet member 26, so that the distance between the document G and the second glass member 16 at the position F serving as the reading position is maintained, and the document G can be read accurately.

[0073] According to the scanner 1 of embodiment 1, the position of the sheet material 26 is detected based on the second size SZ2, which is relatively smaller than the first size SZ1, so that the processing speed required to detect the sheet material 26 can be increased. According to the scanner 1 of the first embodiment, the position F can be identified using the results of shading correction, so that the position F can be identified with high accuracy.

[0074] According to the scanner 1 of the first embodiment, the position of the sheet member 26 is detected based on data on the position P2 where the sheet member 26 overlaps with the origin member 28, so even if the reading unit 20 is tilted with respect to the X direction, it is possible to reduce variations in the reading position in the movement direction due to the tilt of the reading unit 20. This makes it possible to identify the position F with high accuracy. According to the scanner 1 of the first embodiment, it is not necessary to perform the process for setting the position F in each of the first and second modes, so the processing time for setting the position F can be shortened.

[0075] According to the scanner 1 of the first embodiment, the sheet member 26 and the pressing member 56 have different colors, which makes it easier to optically detect the sheet member 26. According to scanner 1 of embodiment 1, when sheet member 26 is fixed to second glass member 16 via adhesive layer 29, even if adhesive layer 29 protrudes outward from the fixing target area inside sheet member 26, adhesive layer 29 is held within space V (FIG. 5) where adhesive layer 29 is not provided, and therefore adhesive layer 29 can be prevented from protruding outward from the edge of sheet member 26. This makes it possible to prevent a decrease in the detection accuracy of the position of sheet member 26.

[0076] According to the scanner 1 of embodiment 1, even if the adhesive layer 29 reaches the edge of the sheet member 26, the color of the adhesive layer 29 is different from the color of the holding member 56, thereby reducing the possibility of erroneously detecting the sheet member 26 as the holding member 56. It is predicted that the more sheets of originals G conveyed by the original conveying unit 46, the more wear will occur on the sheet member 26. Here, according to the scanner 1, even if the sheet member 26 is worn, the position F, which is the reading position, can be corrected based on the sheet member 26 by changing the position F according to the number of sheets of originals G, so that the originals G can be read at the optimal position. According to the control method for the scanner 1 of the first embodiment, it is possible to obtain the same functions and effects as those of the scanner 1 of the first embodiment. Furthermore, according to the control program for the scanner 1 of the first embodiment, it is possible to obtain the same functions and effects as those of the scanner 1 of the first embodiment.

[0077] [Variation 1] A first modification of the scanner 1 of the first embodiment will be described. In the scanner 1 of the first modification, the origin member 28 is attached to a position P3 in the X direction where the origin member 28 overlaps with the guide shaft 18, instead of the position P2. The control unit 30 detects the position of the sheet member 26 based on the data of the position P3. Here, according to the scanner 1 of the first modified example, the origin member 28 can be positioned close to the guide shaft 18, which makes the inclination of the reading unit 20 relative to the X direction relatively small, thereby reducing the influence of the inclination of the reading unit 20 during reading and enabling the position F to be determined with high accuracy.

[0078] [Variation 2] A second modification of the scanner 1 of the first embodiment will be described. In the scanner 1 of the second modification, the control unit 30 causes the document G to be read in either a first mode or a second mode, which have different resolutions in the transport direction of the document G. The position F in the first mode and the position F in the second mode are set to different positions. Here, according to the scanner 1 of the second modification, the position F can be set to a position suitable for the resolution of each of the first mode and the second mode.

[0079] [Embodiment 2] Next, the scanner 1 of embodiment 2 will be described with reference to the accompanying drawings. Note that parts common to the scanner 1 of embodiment 1 are given the same reference numerals and description thereof will be omitted. The scanner 1 of the second embodiment differs from the scanner 1 of the first embodiment in that a step of reading the sheet member 26 is added when the number of documents G conveyed by the document conveying unit 46 exceeds a predetermined number. Other configurations are the same as those of the first embodiment. In the scanner 1 of embodiment 2, when the number of documents G transported by the document transport unit 46 exceeds a predetermined number, the control unit 30 causes the reading unit 20 to read the sheet member 26, and detects wear of the sheet member 26 according to the detected position of the sheet member 26.

[0080] Next, the operation of the scanner 1 of the second embodiment will be described. As shown in FIG. 9, in the flowchart of the second embodiment, steps S2 and S4 are added to the flowchart of the first embodiment (FIG. 8). In step S2, the CPU 32 checks the number of originals G transported by the original transport unit 46. The number of originals G is counted by a counter (not shown). Then, the process proceeds to step S4.

[0081] In step S4, the CPU 32 determines whether the number of conveyed sheets of the original G exceeds a predetermined number. If the number of conveyed sheets of the original G exceeds the predetermined number (S4: Yes), the process proceeds to step S10. If the number of conveyed sheets of the original G is equal to or less than the predetermined number (S4: No), the process proceeds to step S24. Then, the original G is read. Thus, according to the scanner 1 of embodiment 2, when the number of transported originals G exceeds a predetermined number and it is assumed that the sheet member 26 in contact with a portion of the originals G is worn, the worn state of the sheet member 26 can be detected, and replacement of the sheet member 26 can be encouraged.

[0082] The scanner 1 according to embodiments 1 and 2 of the present invention is based on the configuration described above, but it is of course possible to modify, combine, or omit partial configurations within the scope of the present invention.

[0083] In the scanner 1, the size of the data in the X direction when reading the sheet member 26 is not limited to the second size, but may be the first size. Moreover, the size of the data in the X direction when reading the sheet member 26 may be equal to the reading size for shading correction. The control unit 30 may detect the position of the sheet member 26 based on data of a position that does not overlap with the origin member 28. For example, the position of the sheet member 26 may be detected at a position between the guide shaft 18 and the origin member 28 in the X direction.

[0084] As long as detection is possible in scanner 1, the color of pressing member 56 may be the same color as the position of sheet member 26. At the edge of sheet member 26, if the position is not read by reading unit 20, adhesive layer 29 may be provided between the edge of sheet member 26 and second glass member 16. The color of adhesive layer 29 may be the same color as the color of pressing member 56. The control unit 30 does not need to change the position F depending on the number of originals G transported by the original transport unit 46.

[0085] In scanner 1, adhesive layer 29 does not have to be interposed between second glass member 16 and sheet member 26. For example, the Y-direction end of sheet member 26 may be bent into an L-shape, and the vertical part of this bent part may be in contact with the Y-direction end face of second glass member 16.

[0086] As described above, if the sheet member 26 is colored, the sheet member 26 can be read based on the difference in brightness value. If the sheet member 26 is transparent, the sheet member 26 can be detected based on, for example, the difference in the state of light traveling inside and outside the sheet member 26. Alternatively, an identification pattern may be provided on the sheet member 26, and the sheet member 26 may be detected by reading the identification pattern. The position of the edge of the sheet member 26 may be identified by scanning an area of ​​the second glass member 16 where the sheet member 26 is not present.

[0087] The reading unit 20 may read at the first size and then trim the obtained data to perform the determination process at the second size. Alternatively, the reading unit 20 may read at the second size and perform the determination process at the second size. When changing the position F according to the number of sheets of the original G, the sheet material 26 may be re-detected when a predetermined number of sheets have been transported, or the position F may be corrected based on a data table prepared in advance without re-detection. [Explanation of symbols]

[0088] 1...scanner, 10...image reading device, 12...main body frame, 12A...casing, 12B...inner frame, 14...first glass member, 15...middle portion, 16...second glass member, 16A... upper surface, 17... opposing plate, 18... guide shaft, 19... support frame, 20... reading unit, 21...carriage, 24...drive unit, 26...seat member, 27...edge portion, 27A...edge portion, 28... origin member, 29... adhesive layer, 30... control unit, 32... CPU, 34... memory, 36...position detection unit, 40...automatic transport device, 42...original tray, 44...discharge tray, 46... document transport section, 48... transport roller pair, 52... first transport roller pair, 54... second conveying roller pair, 56... holding member, A... position, B... position, C... position, D...position, E...reference position, F...position, G...position, H...position, M...range, P1...position, P2...Position, P3...Position, P4...Position, P5...Position, QA...Paper dust, QB...Adhesive dust, S1...offset, S2...position, SZ1...first size, SZ2...second size, T...Transport path, V...Space, α1...Displacement, β...Set distance

Claims

1. A transparent member; a frame surrounding the transparent member; a sheet member adhered onto the transparent member; a conveying section that conveys the document so that the document contacts the transparent member at a first position in a document conveyance direction and the document contacts the sheet member at a second position in the document conveyance direction; a reading unit that is provided to be movable in a movement direction along the transport direction relative to the transparent member and that reads the document; a control unit that controls the movement and reading operation of the reading unit; Equipped with the reading unit reads the document conveyed by the conveying unit at a third position between the first position and the second position in the movement direction, where the document does not contact the sheet member and the transparent member; the control unit specifies the third position in accordance with the position of the sheet member detected by the reading unit. A reading device characterized by:

2. 2. The reading device according to claim 1, the control unit detects the position of the sheet member based on data acquired from the reading unit, the data having a second size, the size in a width direction perpendicular to the movement direction being smaller than the first size; the first size is the largest size that the reading unit can read the document; A reading device characterized by:

3. 3. The reading device according to claim 2, the control unit causes the reading unit to perform reading for shading correction and reading for detecting the position of the sheet member while the reading unit is moving; a reading size for the shading correction is larger than a reading size for detecting the position of the sheet member in the width direction; A reading device characterized by:

4. 4. The reading device according to claim 2 or 3, a reference member for identifying the position of the reading unit in the movement direction is provided on the frame; the control unit detects the position of the sheet member based on data of the position where the sheet member overlaps with the reference member in the width direction. A reading device characterized by:

5. 5. The reading device according to claim 4, the frame is provided with an axis along the movement direction, the axis guiding the reading unit during movement; the control unit detects the position of the sheet member based on data of a position overlapping with the axis in the width direction. A reading device characterized by:

6. 6. The reading device according to claim 1, the control unit reads the document in either a first mode or a second mode, the first mode and the second mode having different resolutions in the transport direction; The third position in the first mode and the third position in the second mode are set to the same position. A reading device characterized by:

7. 6. The reading device according to claim 1, the control unit reads the document in either a first mode or a second mode, the first mode and the second mode having different resolutions in the transport direction; The third position in the first mode and the third position in the second mode are set to different positions. A reading device characterized by:

8. 8. The reading device according to claim 1, the transport unit has a background member facing the transparent member, The color of the background member is different from the color of the sheet member. A reading device characterized by:

9. 9. The reading device according to claim 1, the sheet member is fixed to the transparent member by an adhesive layer; the adhesive layer is not provided between the edge of the sheet member that is closer to the second position and the transparent member; A reading device characterized by:

10. A reading device according to claim 9 which relies on claim 8, The color of the adhesive layer is different from the color of the background member. A reading device characterized by:

11. 11. The reading device according to claim 1, the control unit changes the third position in accordance with the number of the originals transported by the transport unit. A reading device characterized by:

12. 12. The reading device according to claim 1, When the number of the originals conveyed by the conveying unit exceeds a predetermined number, the control unit causes the reading unit to read the sheet member, and detects wear of the sheet member according to the detected position of the sheet member. A reading device characterized by:

13. 13. The reading device according to claim 1, a size of the sheet member in a width direction perpendicular to the movement direction is smaller than a size of the transparent member in the width direction; A reading device characterized by:

14. A transparent member; a frame surrounding the transparent member; a sheet member adhered onto the transparent member; a conveying section that conveys the document so that the document contacts the transparent member at a first position in a document conveyance direction and the document contacts the sheet member at a second position in the document conveyance direction; a reading unit that is movable relative to the transparent member in a movement direction along the transport direction and that reads the document at a reading position between the first position and the second position; a control unit that controls the movement and reading operation of the reading unit; A control method for a reading device comprising: detecting the position of the sheet member by reading the sheet member while moving the reading unit; specifying the reading position based on the detected position of the sheet member; reading the document by the reading unit at the specified reading position; having A method for controlling a reading device, comprising:

15. A transparent member; a frame surrounding the transparent member; a sheet member adhered onto the transparent member; a conveying section that conveys the document so that the document contacts the transparent member at a first position in a document conveyance direction and the document contacts the sheet member at a second position in the document conveyance direction; a reading unit that is movable relative to the transparent member in a movement direction along the transport direction and that reads the document at a reading position between the first position and the second position; a control unit that controls the movement and reading operation of the reading unit; A control program for a reading device comprising: detecting a position of the sheet member by reading the sheet member while moving the reading unit; specifying the reading position based on the detected position of the sheet member; reading the document by the reading unit at the specified reading position; A control program for a reading device that causes a computer to execute the above.

Images