Image reading apparatus

Abstract

To provide an image reader capable of making a colored part hardly visible and suppressing the deterioration of design in a configuration for correcting the reading range of a reading sensor by using the colored part obtained by coloring the back surface of a cover.SOLUTION: The image reader 1 is provided with an original glass 81, a cover 70 and a read sensor 3S and corrects a read range of the read sensor 70D on the basis of a result of reading a colored part 20 colored to a rear side 3S of the cover 70 by the read sensor 3S. The cover 70 has the recess 10 recessed in the 70D of the back surface and having the first recessed edge 11 extending in the main scanning direction and the second recessed edge 12 extending in the sub-scanning direction, and the colored portion 20 colored in the 70D of the back surface at a position away from the opening 71 and having the first colored edge 21 extending in the main scanning direction along the first recessed edge 11 and the second colored edge 22 extending in the sub-scanning direction along the second recessed edge 12.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to an image reading device. [Background technology]

[0002] Patent Document 1 discloses a reading device that is an example of a conventional image reading device. In this reading device, a document table has a mounting surface and a glass back surface opposite the mounting surface. The top plate has an opening that exposes the mounting surface and covers the outer periphery of the document table from the mounting surface side.

[0003] The reading sensor is located on the rear side of the glass plate and scans the image of the document placed on the document surface in a main scanning direction parallel to the document surface and in a sub-scanning direction parallel to the document surface and perpendicular to the main scanning direction.

[0004] The back surface of the top plate that faces the reading sensor is colored so that the colored portion is adjacent to the left rear corner of the opening.

[0005] The reading device corrects the reading range of the reading sensor based on the result of the reading sensor reading the colored portion, regardless of whether the reflectance of the top plate is low or not. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2023-152008 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the above-mentioned conventional reading device, when a user looks at the left rear corner of the opening from diagonally above, there is a risk that the edge of the colored portion adjacent to the left rear corner of the opening will be visible, which raises concerns about a reduction in design.

[0008] The present invention has been made in consideration of the above-mentioned conventional situation, and aims to provide an image reading device that can make the colored portion difficult to see and suppress a decrease in design, in a configuration in which the reading range of the reading sensor is corrected using a colored portion colored on the back of the cover. [Means for solving the problem]

[0009] The image reading device of the present invention includes an original glass having a placement surface on which an original is placed and a glass back surface opposite to the placement surface; a cover having an opening exposing the placement surface and covering an outer periphery of the document glass from the placement surface side; a reading sensor located on the rear surface of the glass platen, the reading sensor scanning and reading an image of a document placed on the placement surface in a main scanning direction parallel to the placement surface and in a sub-scanning direction parallel to the placement surface and perpendicular to the main scanning direction; Equipped with an image reading device configured to correct a reading range of the reading sensor based on a result of the reading sensor reading a colored portion of the cover that is colored on a back surface thereof that can face the reading sensor, the cover includes a recess formed on the rear surface, the recess having a first recess edge extending in the main scanning direction and a second recess edge extending in the sub-scanning direction; The colored portion is colored on the back surface at a position away from the opening, and has a first colored edge extending in the main scanning direction along the first recessed edge, and a second colored edge extending in the sub-scanning direction along the second recessed edge.

[0010] The image reading device of the present invention corrects the reading range of the reading sensor based on the result of reading the colored portion on the back surface of the cover, regardless of whether the reflectance of the cover is low or not.

[0011] Here, the colored portion has a first colored edge and a second colored edge. The first colored edge extends in the main scanning direction along the first recessed edge of the recess, thereby achieving high positional accuracy. The second colored edge also extends in the sub-scanning direction along the second recessed edge of the recess, thereby achieving high positional accuracy. As a result, this image reading device can accurately correct the reading range of the reading sensor.

[0012] The colored portion is colored on the back surface at a position away from the opening, so that when a user looks at a portion of the opening located near the colored portion from diagonally above, the colored portion is less likely to be in the user's field of view.

[0013] Therefore, in the image reading device of the present invention, in a configuration in which the reading range of the reading sensor is corrected using a colored portion colored on the back surface of the cover, the colored portion can be made difficult to see, thereby preventing a decrease in design. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view of an image reading apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic partial cross-sectional view of the image reading device according to the embodiment. [Figure 3] FIG. 3 is a partial perspective view showing the cover. [Figure 4] FIG. 4 is a partial perspective view showing the cover, the first platen glass, and the second platen glass. [Figure 5] FIG. 5 is a partial bottom view showing the cover, the colored portion, and the black and white reference portion. [Figure 6] FIG. 6 is a partial perspective view showing the cover and the colored portion. [Figure 7] FIG. 7 is a partial cross-sectional view showing the cross section AA of FIG. [Figure 8] FIG. 8 is a partial cross-sectional view showing the cross section BB of FIG. [Figure 9] FIG. 9 is a schematic partial bottom view showing the cover, the colored portion, and the black and white reference portion, and is a diagram for explaining the reference boundary position, the reference intersection position, the measured boundary position, and the measured intersection position. [Figure 10] FIG. 10 is a flowchart showing the calculation process of the black and white reference portion correction value and the recessed portion correction value. [Figure 11] FIG. 11 is a flowchart showing the document reading process. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

[0016] (Example) As shown in Fig. 1, an image reading device 1 of the embodiment is one example of a specific aspect of the image reading device of the present invention. In Fig. 1, the operation panel 8P side of the image reading device 1 is the front. The side that is to the left when facing the operation panel 8P is the left side. The front-rear direction, left-right direction, and up-down direction shown in Fig. 2 and subsequent figures are all displayed in accordance with the directions shown in Fig. 1.

[0017] As shown in FIG. 1, the image reading device 1 includes a main body 8 and a document cover 9.

[0018] <Main body> The main body 8 is a flat, approximately box-shaped body. An operation panel 8P, such as a touch panel, is located on the front side of the main body 8. The main body 8 accommodates the image forming unit 2 and the control unit C1 in its lower portion.

[0019] The image forming unit 2 forms an image on a sheet by an inkjet method, a laser method, or the like.

[0020] The control unit C1 is an electronic circuit unit including a CPU (not shown) that performs arithmetic processing, an interface circuit (not shown) that controls motors, sensors, etc., and a storage unit C1M.

[0021] The storage unit C1M has a ROM and a RAM (not shown). The ROM stores programs for the CPU to control various operations of the image reading device 1, programs for executing the recognition process, etc. The RAM functions as a storage area for temporarily recording data and signals used when the CPU executes the programs, or as a work area for data processing.

[0022] The control unit C1 performs overall control over each unit of the image reading device 1, including control of the image forming unit 2 and the image reading unit 3 (described later).

[0023] 1, the main body 8 has a cover 70, a first document glass 81, and a second document glass 82. The first document glass 81 is an example of the "document glass" in the present invention.

[0024] The cover 70 is located on the top surface of the main body 8. The cover 70 is a frame-shaped resin molded product having a first opening 71 and a second opening 72. The first opening 71 is an example of the "opening" in the present invention.

[0025] The first opening 71 is a rectangular opening. The second opening 72 is a rectangular opening that is located to the left of the first opening 71 and is elongated in the front-rear direction.

[0026] As shown in FIGS. 1 to 3, the cover 70 has a left frame portion 79 and a partition portion 77.

[0027] 1 and 3, the left frame portion 79 extends in a generally flat plate shape in the front-to-rear and left-to-right directions and includes the left edge of the cover 70. The front end of the left frame portion 79 is connected to the left end of the front frame portion 78A of the cover 70. The rear end of the left frame portion 79 is connected to the left end of the rear frame portion 78B of the cover 70.

[0028] A right edge 79R of the left frame portion 79 defines a left opening edge that extends in the front-rear direction on the left side of the second opening 72.

[0029] The partition portion 77 is elongated and extends in the front-to-rear direction at a position separated to the right from the left frame portion 79. The front end of the partition portion 77 is connected to the front frame portion 78A of the cover 70. The rear end of the partition portion 77 is connected to the rear frame portion 78B of the cover 70.

[0030] The right edge 77R of the partition 77 defines a left opening edge that extends in the front-rear direction on the left side of the first opening 71. The left edge 77L of the partition 77 defines a right opening edge that extends in the front-rear direction on the right side of the second opening 72.

[0031] 1 and 2, the partition 77 has a scoop guide 77G. The scoop guide 77G is an inclined surface that slopes upward to the right from the left edge 77L of the partition 77. The apex of the scoop guide 77G is located at a position spaced apart to the left and above the right edge 77R of the partition 77.

[0032] In this embodiment, the cover 70 is manufactured by injection molding of a thermoplastic resin. Furthermore, in this embodiment, recycled plastic material is used as the thermoplastic resin for the cover 70 in order to contribute to environmental protection, and the cover 70 is manufactured without painting. Therefore, the color of the cover 70 is black or gray, which makes aging due to ultraviolet rays and the like less noticeable.

[0033] 2 and 3, a reinforcing plate accommodating portion 77A is recessed on the opposite side of the scoop guide 77G in the partition portion 77. As shown in FIGS. 2 and 4, the reinforcing plate accommodating portion 77A accommodates a reinforcing plate 76. The reinforcing plate 76 is a steel plate bent into a crank-shaped cross section, and reinforces the partition portion 77.

[0034] 2 and 4, the first document glass 81 is disposed on the rear surface 70D side of the cover 70. Although not shown, the first document glass 81 is fixed to the cover 70 by having a part of the outer periphery 81E attached to the rear surface 70D of the cover 70 with double-sided tape and by having the other part of the outer periphery 81E sandwiched between the cover 70 and a member attached to the cover 70 from below.

[0035] Similar to the first platen glass 81, the second platen glass 82 is also disposed on the rear surface 70D side of the cover 70.

[0036] 1 and 2, the first original glass 81 has a placement surface 81U. The placement surface 81U is a flat surface on the upper surface of the first original glass 81 that is exposed by the first opening 71, and extends in the front-rear and left-right directions.

[0037] As shown in FIG. 1, the cover 70 covers the outer periphery 81E of the first platen glass 81 from the placement surface 81U side, that is, from above, with the partition 77, front frame 78A, rear frame 78B, and right frame 78R.

[0038] The document SH to be read is placed on the placement surface 81U. The document SH to be read may be a sheet such as paper, an OHP sheet, or a book.

[0039] 2 and 4, the first original glass 81 has a glass rear surface 81D. The glass rear surface 81D is a flat surface on the first original glass 81 opposite to the placement surface 81U.

[0040] 1 and 2, the second document glass 82 has a reading surface 82U. The reading surface 82U is a flat surface on the upper surface of the second document glass 82 that is exposed by the second opening 72. The reading surface 82U is located to the left of the placement surface 81U and extends in an elongated shape in the front-to-rear direction. The reading surface 82U is used when the conveying unit 4, which will be described later, is operated.

[0041] As shown in Figures 2 and 4, a thin film 89 is attached to the back surface 81D of the first original glass 81, the back surface of the second original glass 82, and the back surface of the reinforcing plate 76 to eliminate any steps between them.

[0042] 2, the main body 8 accommodates the image reading unit 3 in its upper portion. The image reading unit 3 has a reading sensor 3S and a scanning mechanism 3M. The control unit C1 controls the reading sensor 3S and the scanning mechanism 3M.

[0043] The reading sensor 3S and the scanning mechanism 3M are located on the rear surface 81D side of the first document glass 81.

[0044] The reading sensor 3S is a well-known image reading sensor that uses a CIS (Contact Image Sensor) or a CCD (Charge Coupled Device). The reading sensor 3S has multiple reading elements 3S1. The reading elements 3S1 are aligned in the main scanning direction. The main scanning direction is parallel to the placement surface 81U, which is the front-to-rear direction in this embodiment.

[0045] The scanning mechanism 3M has a carriage 3C that holds the reading sensor 3S. The scanning mechanism 3M moves the reading sensor 3S back and forth in the sub-scanning direction by using rails, motors, pulleys, timing belts, etc. (not shown) that act on the carriage 3C. The sub-scanning direction is parallel to the placement surface 81U and perpendicular to the main scanning direction, which is the left-right direction in this embodiment.

[0046] The carriage 3C has multiple rollers 3C1. Two of the rollers 3C1 are located behind the reading elements 3S1. Although not shown, the other two rollers 3C1 are located in front of the reading elements 3S1, i.e., on the front side of the paper in FIG. 2.

[0047] When the carriage 3C reciprocates in the left-right direction, the rollers 3C1 rotate while successively contacting the rear surface 81D of the first platen glass 81, the film 89, and the rear surface of the second platen glass 82.

[0048] As a result, the carriage 3C maintains constant the vertical distance between the rear surface 81D of the first platen glass 81 and each reading element 3S1, and the vertical distance between the rear surface of the second platen glass 82 and each reading element 3S1.

[0049] The back surface 70D of the cover 70 can face the reading sensor 3S. Specifically, the back surface 70D of the cover 70 has a back surface 70D1 located between the right edge 77R of the partition portion 77 and the reinforcing plate accommodating portion 77A, and a back surface 70D2 of the left frame portion 79.

[0050] A rear surface 70D1 of the partition portion 77 can face the reading sensor 3S passing under the partition portion 77. A rear surface 70D2 of the left frame portion 79 can face the reading sensor 3S moving leftward from the reading surface 82U.

[0051] When the image reading unit 3 reads an image of a document SH placed on the placement surface 81U, the reading sensor 3S moves rightward, i.e., in the sub-scanning direction, from a position to the left of the placement surface 81U by operation of the scanning mechanism 3M, and begins reading the image using each reading element 3S1 when it reaches the left edge of the placement surface 81U. Then, while moving in the sub-scanning direction below the placement surface 81U, each reading element 3S1 reads the image of the document SH in a line shape in the main scanning direction. When the reading sensor 3S moves below the right edge of the placement surface 81U, it stops reading the image and returns to its standby position by operation of the scanning mechanism 3M. The standby position of the reading sensor 3S is a position to the left of the reading surface 81U.

[0052] How the control unit C1 determines the reading start point, which means that the reading sensor 3S has reached the left end of the placement surface 81U (the right edge 77R of the partition 77), will be described in detail later.

[0053] When the transport unit 4, which will be described later, is operated, the reading sensor 3S moves to a stationary reading position below the reading surface 82U by the operation of the scanning mechanism 3M, and remains stationary there.

[0054] <Manuscript cover> 1, the document cover 9 is located above the main body 8. The rear end of the document cover 9 is connected to the rear end of the main body 8 via a hinge (not shown). The document cover 9 is swingable around a swing axis X9 extending in the left-right direction.

[0055] A document holder 9P is attached to the bottom surface of the document cover 9. The document holder 9P has a white resin sheet that can come into contact with the placement surface 81U, and a sponge sheet that is positioned between the resin sheet and the bottom surface of the document cover 9.

[0056] When the document cover 9 is open, it exposes the placement surface 81U, allowing the user to place and remove documents on and from the placement surface 81U.

[0057] 2, when the document cover 9 is closed, its bottom surface covers the placement surface 81U and the reading surface 82U. Although not shown, a document presser 9P brings the document SH placed on the placement surface 81U into close contact with the placement surface 81U when the document cover 9 is closed.

[0058] <Transportation section> 1 and 2, the document cover 9 houses the transport unit 4 in its left portion. The document cover 9 also has a supply tray and a discharge tray (not shown) in its left portion.

[0059] 2, the conveying unit 4 conveys a sheet supported on a supply tray (not shown) along a conveying path P1, passes the sheet over the reading surface 82U, and then discharges the sheet onto a discharge tray (not shown). The scooping guide 77G scoops up the sheet that has passed over the reading surface 82U.

[0060] When the image reading unit 3 reads an image on a sheet supported on a supply tray (not shown), the control unit C1 moves the reading sensor 3S to a stationary reading position and then activates the conveying unit 4. As a result, the reading sensor 3S at the stationary reading position reads an image on the sheet SH that is conveyed by the conveying unit 4 and passes over the reading surface 82U. When there are no more sheets supported on the supply tray, the control unit C1 ends image reading by the reading sensor 3S and stops the conveying unit 4. Then, the control unit C1 returns the reading sensor 3S to the standby position.

[0061] Next, it will be explained how the control unit C1 determines the reading start point of the reading sensor 3S when the image reading unit 3 reads an image of the document SH placed on the placement surface 81U. The reading start point of the reading sensor 3S is an example of the "reading range of the reading sensor" in the present invention.

[0062] <Black and white reference section> 2, 3, and 5, the cover 70 has a black and white reference portion 30. The black and white reference portion 30 is a substantially rectangular tape that is elongated in the front-to-rear direction. The black and white reference portion 30 is provided on the back surface 70D of the cover 70.

[0063] More specifically, the black and white reference portion 30 is attached to the back surface 70D2 of the left frame portion 79. The right edge of the black and white reference portion 30 is located to the left of the right edge 79R of the left frame portion 79. As shown in FIG. 3 , the black and white reference portion 30 has a white portion 31 and a black portion 32.

[0064] Two black portions 32 are provided at the front and rear ends of the black and white reference portion 30. The front black portion 32 is rectangular and includes the front and right corners of the black and white reference portion 30, and extends in an elongated shape in the front-to-back direction. The rear black portion 32 is rectangular and includes the rear and right corners of the black and white reference portion 30, and extends in an elongated shape in the front-to-back direction.

[0065] The white portion 31 is a portion of the black and white reference portion 30 other than the two black portions 32. In this embodiment, processing using the rear black portion 32 and the rear end portion of the white portion 31 adjacent to the rear black portion 32 will be described, and processing using other portions of the black and white reference portion 30 will be omitted.

[0066] As shown in FIG. 5, the rear black portion 32 and the rear end of the white portion 31 have a first boundary 30B1 and a second boundary 30B2.

[0067] The first boundary 30B1 is the boundary between the left edge of the rear black portion 32 and the rear end portion of the white portion 31, and extends linearly in the main scanning direction.

[0068] The second boundary 30B2 is the boundary between the leading edge of the rear black portion 32 and the trailing end of the white portion 31, and extends linearly in the sub-scanning direction.

[0069] <Concave> 2, 3, 5, and 6, the cover 70 has a recess 10. The recess 10 is recessed into the rear surface 70D of the cover 70.

[0070] More specifically, the recess 10 is recessed upward from the rear surface 70D1 of the partition 77 on the rear end side of the partition 77. As shown in Fig. 5, the recess 10 is located leftward from the right edge 77R of the partition 77 and rightward from the reinforcing plate accommodating portion 77A.

[0071] In other words, the recess 10 is located near the left rear corner of the first opening 71 and is spaced to the left of the left edge of the first opening 71. The black and white reference portion 30 is located on the opposite side of the recess 10 from the first opening 71 in the sub-scanning direction.

[0072] As shown in Fig. 6, the recess 10 has an L-shaped outline. The recess 10 is formed by an L-shaped imprint on a core embedded in the mold surface of an injection molding die.

[0073] The recess 10 has a first recess edge 11 and a second recess edge 12. The first recess edge 11 and the second recess edge 12 form two sides located on the inside of an L-shaped bend in the outline of the recess 10. The first recess edge 11 extends linearly in the main scanning direction. The second recess edge 12 extends linearly in the sub-scanning direction.

[0074] The recess 10 also has a third recess edge 13 and a fourth recess edge 14. The third recess edge 13 and the fourth recess edge 14 form two outer sides of the L-shaped bend in the contour of the recess 10. The third recess edge 13 extends linearly in the main scanning direction at a position spaced to the left of the first recess edge 11. The fourth recess edge 14 extends linearly in the sub-scanning direction at a position spaced rearward from the second recess edge 12.

[0075] 7, the radius R1 of the rounded corners of the first recessed edge 11 is equal to or less than one pixel LP1 of the reading resolution of the reading sensor 3S. In this embodiment, the reading resolution of the reading sensor 3S is 600 dpi (dots per inch), and one pixel LP1 of the reading resolution of the reading sensor 3S is 0.042 mm. In this embodiment, the radius R1 of the rounded corners of the first recessed edge 11 is set to 0.040 mm or less.

[0076] 8, the radius R2 of the rounded corners of the second recessed edge 12 is equal to or smaller than one pixel LP1 of the reading resolution of the reading sensor 3S, as is the radius R1. In this embodiment, the radius R2 of the rounded corners of the second recessed edge 12 is also set to be equal to or smaller than 0.040 mm.

[0077] In this embodiment, a pin angle (an unchamfered corner) is formed by butting another core against the inside of the L-shaped bend of the stamp on the core embedded in the mold surface of the injection molding mold, thereby achieving a corner rounding radius R1≦0.040 mm for the first recessed edge 11 and a corner rounding radius R2≦0.040 mm for the second recessed edge 12.

[0078] On the other hand, in this embodiment, the third recessed edge 13 and the fourth recessed edge 14 are formed by forming chamfered corners with a cutting tool on the outside of the L-shaped bend of the marking on the core embedded in the mold surface of the injection molding die. Therefore, the corner rounding radius R3 of the third recessed edge 13 shown in Fig. 7 and the corner rounding radius R4 of the fourth recessed edge 14 shown in Fig. 8 tend to be larger than the corner rounding radius R1 of the first recessed edge 11 and the corner rounding radius R2 of the second recessed edge 12.

[0079] <Colored part> 2, 3, 5, and 6, the cover 70 has a colored portion 20. The colored portion 20 is colored on the back surface 70D of the cover 70 at a position spaced apart from the first opening 71 to the left.

[0080] 6, the colored portion 20 is colored on the rear surface 70D1 of the partition 77 at the rear end side of the partition 77, and surrounds the recess 10. The outer contour of the colored portion 20 is rectangular, and surrounds the entire L-shaped contour of the recess 10.

[0081] The colored portion 20 is located at a position spaced to the left from the right edge 77R of the partition portion 77 and at a position spaced to the right from the reinforcing plate accommodating portion 77A.

[0082] In other words, the colored portion 20 is located near the left rear corner of the first opening 71, and is spaced to the left from the left edge of the first opening 71. The distance SD1 by which the colored portion 20 is spaced to the left from the left edge of the first opening 71 is preferably about several tenths of a millimeter to several millimeters. In this embodiment, the distance SD1 is set to 0.5 mm.

[0083] In this embodiment, the colored portion 20 is colored by pad printing on the rear surface 70D1 of the partition portion 77. Pad printing is a printing method in which a colored layer formed on an intaglio plate is primarily transferred to a silicone pad, and the silicone pad is then pressed against the surface to be colored to secondarily transfer the colored layer to the surface to be colored.

[0084] In this embodiment, the color of the colored portion 20 is white, which has a higher reflectance than the color of the cover 70 .

[0085] The colored portion 20 has a first colored edge 21 and a second colored edge 22. The first colored edge 21 extends linearly in the main scanning direction along the first recessed edge 11. The second colored edge 22 extends linearly in the sub-scanning direction along the second recessed edge 12.

[0086] In pad printing, if the surface to be colored has a recess and the radius of the rounded corners of the recess is large, the elastic deformation of the silicone pad will have difficulty following the rounded corners of the edge. As a result, when a coloring layer is transferred from the silicone pad to the rounded corners of the edge, the coloring will have difficulty adhering to the part of the rounded corner near the bottom of the recess, and will tend to be more likely to be adhering to the very edge of the rounded corner opposite the side near the bottom of the recess.

[0087] 7, because the radius R1 is equal to or less than one pixel LP1, even if the coloring is placed at the very edge of the rounded corner of the first recessed edge 11, the deviation of the first colored edge 21 from the first recessed edge 11 is equal to or less than one pixel LP1. Here, "the very edge of the rounded corner of the first recessed edge 11" refers, more specifically, to the very edge of the rounded corner of the first recessed edge 11 on the side opposite to the side closer to the bottom of the recess 10, and refers to the very bottom edge of the rounded corner of the first recessed edge 11 that connects with the back surface 70D1 of the partition portion 77.

[0088] 8, because the radius R2 is equal to or less than one pixel LP1, even if the coloring is placed at the very edge of the rounded corner of the second recessed edge 12, the deviation of the second colored edge 22 from the second recessed edge 12 is equal to or less than one pixel LP1. Here, "the very edge of the rounded corner of the second recessed edge 12" refers, more specifically, to the very edge of the rounded corner of the second recessed edge 12 on the side opposite to the side closer to the bottom of the recess 10, and to the very bottom edge of the rounded corner of the second recessed edge 12 that connects with the back surface 70D1 of the partition portion 77.

[0089] In the manufacturing process of the image reading device 1, the first boundary 30B1 and the second boundary 30B2 of the black and white reference portion 30 are attached to the rear surface 70D2 of the left frame portion 79 by an operator, so the positioning accuracy of the first boundary 30B1 and the second boundary 30B2 is likely to be low.

[0090] On the other hand, in the manufacturing process of the image reading device 1, the first recessed edge 11 and the second recessed edge 12 of the recess 10 are formed by an injection molding die, so that positioning accuracy is high. The first colored edge 21 and the second colored edge 22 of the colored portion 20 are colored by pad printing so as to follow the first recessed edge 11 and the second recessed edge 12, so that positioning accuracy is high, just like the first recessed edge 11 and the second recessed edge 12.

[0091] For this reason, the image reading device 1 is configured to correct the reading range, i.e., the reading start point, of the reading sensor 3S based on the results of the reading sensor 3S reading the first boundary 30B1 and the second boundary 30B2 of the black and white reference portion 30 and the results of the reading sensor 3S reading the first colored edge 21 and the second colored edge 22 of the colored portion 20, as described below.

[0092] <Calculation process of black and white reference portion correction value and recessed portion correction value> When final inspections such as operational checks are performed on the image reading device 1 before shipment, the control unit C1 stores information regarding the reference boundary position SP1 (SP1X, SP1Y) and the reference intersection position SP2 (SP2X, SP2Y) in the memory unit C1M, as shown in Figure 9.

[0093] The reference boundary position SP1 (SP1X, SP1Y) is a reference position that is the boundary between the white portion 31 and the black portion 32, and is a position determined by design. The reference boundary position SP1 (SP1X, SP1Y) is a position determined by design of the intersection where the first boundary 30B1 and the second boundary 30B2 intersect. SP1X is a coordinate in the main scanning direction, and SP1Y is a coordinate in the sub-scanning direction.

[0094] The reference intersection position SP2 (SP2X, SP2Y) is the reference position of the intersection point where the first colored edge 21 and the second colored edge 22 intersect, and is a position determined by design. SP2X is the coordinate in the main scanning direction when SP1X is the origin of the main scanning direction. SP2Y is the coordinate in the sub-scanning direction when SP1Y is the origin of the sub-scanning direction.

[0095] Then, the control unit C1 executes a process of calculating the black and white reference portion correction value and the recessed portion correction value, as shown in FIG.

[0096] First, in step S101, the control unit C1 executes home position detection. The control unit C1 activates the scanning mechanism 3M and moves the reading sensor 3S to the left limit position closest to the left wall of the main body 8. Then, the control unit C1 moves the reading sensor 3S in the sub-scanning direction, i.e., to the right, and causes each reading element 3S1 to read the image of the black and white reference portion 30 line by line.

[0097] Next, the control section C1 proceeds to step S102, and determines the measured boundary position AP1 (AP1X, AP1Y) shown in FIG. 9 based on the result of having the reading sensor 3S read the black and white reference section 30.

[0098] The measured boundary position AP1 (AP1X, AP1Y) is the measured position of the boundary between the white portion 31 and the black portion 32, and is a position that reflects the attachment error of the black and white reference portion 30. The measured boundary position AP1 (AP1X, AP1Y) is the measured position of the intersection where the first boundary 30B1 and the second boundary 30B2 intersect. AP1X is the coordinate in the main scanning direction, and AP1Y is the coordinate in the sub-scanning direction. The control unit C1 determines the measured boundary position AP1 (AP1X, AP1Y) as the home position.

[0099] Next, the control unit C1 proceeds to step S103 shown in Fig. 10, where it calculates the black and white reference portion correction value H1 (H1X, H1Y) based on the stored information about the reference boundary position SP1 (SP1X, SP1Y) and the determined measured boundary position AP1 (AP1X, AP1Y). H1X is the correction value in the main scanning direction (H1X = AP1X - SP1X). H1Y is the correction value in the sub-scanning direction (H1Y = AP1Y - SP1Y).

[0100] Next, the control unit C1 proceeds to step S104, and while moving the reading sensor 3S in the sub-scanning direction, each reading element 3S1 reads the image of the recess 10 and the portion of the colored portion 20 that aligns with the recess 10, line by line, and stores the image information in the memory unit C1M.

[0101] This reading operation is an operation in which the reading sensor 3S reads the first colored edge 21 and the second colored edge 22, and the image information stored in the memory unit C1M includes image information about the first colored edge 21 and the second colored edge 22.

[0102] At this time, the control unit C1 performs edge enhancement processing on the image information stored in the storage unit C1M, thereby enhancing the image information relating to the first colored edge 21 and the second colored edge 22.

[0103] Next, the control unit C1 proceeds to step S105, where it determines the measured intersection position AP2 (AP2X, AP2Y) shown in FIG. 9 based on the results of having the reading sensor 3S read the first colored edge 21 and the second colored edge 22.

[0104] The measured intersection position AP2 (AP2X, AP2Y) is the measured position of the intersection point where the first colored edge 21 and the second colored edge 22 intersect. AP2X is the coordinate in the main scanning direction when AP1X is the origin of the main scanning direction. AP2Y is the coordinate in the sub-scanning direction when AP1Y is the origin of the sub-scanning direction.

[0105] In this case, the control unit C1 performs simple binarization and black-and-white inversion on the image information relating to the first colored edge 21 and the second colored edge 22 to emphasize the edge pixels, extracts a group of multiple candidate points from the emphasized edge pixels, and performs an estimation process for the first colored edge 21 and the second colored edge 22.

[0106] Next, the control unit C1 proceeds to step S106 shown in Fig. 10, where it calculates recess correction values ​​H2 (H2X, H2Y) based on the stored information about the reference intersection position SP2 (SP2X, SP2Y) and the determined measured intersection position AP2 (AP2X, AP2Y). H2X is the correction value in the main scanning direction (H2X = AP2X - SP2X). H2Y is the correction value in the sub-scanning direction (H2Y = AP2Y - SP2Y).

[0107] Then, the control unit C1 stores the black and white reference portion correction values ​​H1 (H1X, H1Y) and the recessed portion correction values ​​H2 (H2X, H2Y) in the storage unit C1M, and then ends this process.

[0108] <Document reading process> 9, the control unit C1 stores in advance the distance SL1 in the sub-scanning direction from the reference boundary position SP1 (SP1X, SP1Y) to the left end of the placement surface 81U (the right edge 77R of the partition portion 77). There is almost no difference between the designed distance and the distance after manufacture for the distance SL1.

[0109] When the user instructs the control section C1 to start the reading operation of the original SH, the control section C1 executes the original reading process shown in FIG.

[0110] First, in step S111, the control unit C1 determines the reading start point.

[0111] The control unit C1 corrects the reading start point in the main scanning direction to be equal to "design reading start point in the main scanning direction" + "main scanning direction black and white reference portion correction value H1X" + "main scanning direction recessed portion correction value H2X."

[0112] The control unit C1 corrects the reading start point in the sub-scanning direction so that it becomes "measured intersection position AP2Y in the sub-scanning direction" + "distance SL1" + "sub-scanning direction recess correction value H2Y".

[0113] Next, the control unit C1 proceeds to step S112 and activates the scanning mechanism 3M to move the reading sensor 3S from the standby position in the sub-scanning direction. When the reading sensor 3S reaches the corrected reading start point in the sub-scanning direction, the control unit C1 determines that the reading sensor 3S has reached the left end of the placement surface 81U (the right edge 77R of the partition 77), and starts reading the image with each reading element 3S1. As a result, margins are less likely to occur at the start of reading in the acquired image information.

[0114] After the reading sensor 3S reads the image of the document SH placed on the placement surface 81U, the control section C1 ends this process.

[0115] <Action and effect> As shown in Figures 10 and 11, the image reading device 1 of the embodiment corrects the reading range, i.e., the reading start point, of the reading sensor 3S based on the result of the reading sensor 3S reading the colored portion 20 colored on the back surface 70D of the cover 70, regardless of whether the reflectivity of the cover 70 is low or not.

[0116] 6, the colored portion 20 has a first colored edge 21 and a second colored edge 22. The first colored edge 21 extends in the main scanning direction along the first recessed edge 11 of the recess 10, thereby achieving high positional accuracy. The second colored edge 22 also extends in the sub-scanning direction along the second recessed edge 12 of the recess 10, thereby achieving high positional accuracy. As a result, the image reading device 1 can accurately correct the reading start point of the reading sensor 3S.

[0117] The colored portion 20 is colored on the back surface 70D of the cover 70, more specifically, on the back surface 70D1 of the partition portion 77, at a position away from the first opening 71 to the left. As a result, as shown in FIG. 1 , when a user looks at a portion of the first opening 71 located near the colored portion 20, i.e., the left rear corner of the first opening 71, from diagonally above, the colored portion 20 is unlikely to come into the user's field of vision.

[0118] Therefore, in the image reading device 1 of the embodiment, in a configuration in which the reading start point of the reading sensor 3S is corrected using a colored portion 20 colored on the back surface 70D of the cover 70, the colored portion 20 can be made difficult to see, thereby suppressing a decrease in design.

[0119] In addition, in the conventional reading device, the colored portion is colored adjacent to the left rear corner of the opening, so if the document holder attached to the bottom surface of the document cover is the same color as the colored portion and the document holder is adjacent to the colored portion, a problem may occur in which the reading sensor has difficulty identifying the colored portion. In this regard, the image reading device 1 of the embodiment can prevent such a problem by coloring the colored portion 20 on the back surface 70D of the cover 70 at a position away from the first opening 71.

[0120] In addition, in this image reading device 1, as shown in FIG. 7, the radius R1 of the rounded corner of the first recessed edge 11 is equal to or less than one pixel LP1 of the reading resolution of the reading sensor 3S. As shown in FIG. 8, the radius R2 of the rounded corner of the second recessed edge 12 is equal to or less than one pixel LP1 of the reading resolution of the reading sensor 3S. With this configuration, even if the coloring is placed at the very edge of the rounded corner of the first recessed edge 11, the deviation of the first colored edge 21 from the first recessed edge 11 is equal to or less than one pixel LP1. Also, even if the coloring is placed at the very edge of the rounded corner of the second recessed edge 12, the deviation of the second colored edge 22 from the second recessed edge 12 is equal to or less than one pixel LP1. As a result, this image reading device 1 can more accurately correct the reading start point of the reading sensor 3S.

[0121] Furthermore, in this image reading device 1, as shown in FIG. 2, the reading sensor 3S has multiple reading elements 3S1 aligned in the main scanning direction, and the reading sensor 3S moves in the sub-scanning direction. As shown in FIG. 3, the cover 70 has a black-and-white reference portion 30, which has a white portion 31 and a black portion 32, and is provided on the back surface 70D. The black-and-white reference portion 30 is located on the opposite side of the recess 10 from the first opening 71 in the sub-scanning direction. With this configuration, the colored portion 20 is located between the black-and-white reference portion 30 and the first opening 71 in the sub-scanning direction, making it easy to reduce the movement range of the reading sensor 3S in the sub-scanning direction. As a result, this image reading device 1 can be made more compact in the sub-scanning direction.

[0122] 10 and 11, in the image reading device 1, the control unit C1 determines the measured intersection position AP2 (AP2X, AP2Y) based on the results of having the reading sensor 3S read the first colored edge 21 and the second colored edge 22, and corrects the reading start point based on the measured intersection position AP2 (AP2X, AP2Y). This configuration allows the reading start point of the reading sensor 3S to be corrected with even greater accuracy.

[0123] Furthermore, in this image reading device 1, the control unit C1 stores information regarding the reference boundary position SP1 (SP1X, SP1Y) and the reference crossing position SP2 (SP2X, SP2Y). The control unit C1 determines the measured boundary position AP1 (AP1X, AP1Y) based on the result of having the reading sensor 3S read the black-and-white reference portion 30. The control unit C1 determines the measured crossing position AP2 (AP2X, AP2Y) based on the result of having the reading sensor 3S read the first colored edge 21 and the second colored edge 22. The control unit C1 then corrects the reading start point based on the stored information regarding the reference crossing position SP2 (SP2X, SP2Y) and the reference boundary position SP1 (SP1X, SP1Y) and the determined measured crossing position AP2 (AP2X, AP2Y) and the measured boundary position AP1 (AP1X, AP1Y). This configuration allows the reading start point of the reading sensor 3S to be corrected with even greater precision.

[0124] 6, the recess 10 has an L-shaped outline. The first recess edge 11 and the second recess edge 12 form two sides located on the inside of the L-shaped bend in the outline. This configuration simplifies the recess 10. The first recess edge 11, the second recess edge 12, the first colored edge 21, and the second colored edge 22 can be formed with high precision by butting another core against the inside of the L-shaped bend of the marking on the core embedded in the mold surface of the injection molding die.

[0125] Furthermore, in this image reading device 1, the cover 70 is black or gray in color. The colored portion 20 is white in color. With this configuration, the cover 70 is made of recycled plastic material and manufactured unpainted, thereby contributing to environmental protection, and the color options for the cover 70 are increased, improving design, while allowing the reading sensor 3S to suitably read the first colored edge 21 and the second colored edge 22.

[0126] Although the present invention has been described above with reference to the examples, it goes without saying that the present invention is not limited to the above examples and can be modified and applied as appropriate within the scope of the invention.

[0127] In the embodiment, the image reading device of the present invention is embodied as an image reading device 1 having an image reading function and an image forming function, but the present invention is not limited to this configuration. For example, the configuration of the present invention may be applied to an image reading device having only an image reading function.

[0128] In the embodiment, the recess 10 has an L-shaped contour, but the present invention is not limited to this configuration and the recess may have any shape. Also, the recess may be divided into a first recess having a first recess edge and a second recess having a second recess edge.

[0129] In the embodiment, the color of the cover 70 is black or gray, and the colored portion 20 is white, but the present invention is not limited to this configuration. Depending on the reading accuracy of the reading sensor 3S, the colored portion may have a reflectance or the like different enough to be distinguishable from the cover 70.

[0130] In the embodiment, the reading start point is determined based on the positional deviation between the black and white reference portion 30 and the recessed portion 10, but the present invention is not limited to this configuration. For example, without the black and white reference portion 30, the position of the recessed portion 10 may be detected before the start of reading, and the reading start point may be determined based on that position. [Explanation of symbols]

[0131] 1...Image reading device, SH...Original 81U: Placement surface, 81D: Back of glass 81...Original glass (first original glass) 71...Opening (first opening), 70...Cover 81E...Outer edge of the document glass (first document glass) 3S...reading sensor, 70D...back of cover 20...Colored portion, 10...Concave portion 11...first recess edge, 12...second recess edge 21...First colored edge, 22...Second colored edge R1... Radius of the first recess edge R2...radius of the second recess edge LP1...1 pixel of reading resolution of reading sensor 3S 3S1...reading element, 30...black and white reference section 31...white part, 32...black part, C1...control part AP1: Measured boundary position, AP2: Measured intersection position SP1: Reference boundary position, SP2: Reference intersection position

Claims

1. an original glass having a placement surface on which an original is placed and a glass back surface opposite to the placement surface; a cover having an opening exposing the placement surface and covering an outer periphery of the document glass from the placement surface side; a reading sensor located on the rear surface of the glass platen, the reading sensor scanning and reading an image of a document placed on the placement surface in a main scanning direction parallel to the placement surface and in a sub-scanning direction parallel to the placement surface and perpendicular to the main scanning direction; Equipped with an image reading device configured to correct a reading range of the reading sensor based on a result of the reading sensor reading a colored portion of the cover that is colored on a back surface thereof that can face the reading sensor, the cover includes a recess formed on the rear surface, the recess having a first recess edge extending in the main scanning direction and a second recess edge extending in the sub-scanning direction; an image reading device characterized by having a colored portion colored on the back surface at a position away from the opening, the colored portion having a first colored edge extending in the main scanning direction along the first recessed edge and a second colored edge extending in the sub-scanning direction along the second recessed edge.

2. 2. The image reading device according to claim 1, wherein the radius of the rounded corners of the first recess edge and the second recess edge is equal to or less than one pixel of the reading resolution of the reading sensor.

3. the reading sensor has a plurality of reading elements arranged in the main scanning direction, and the reading sensor moves in the sub-scanning direction; 3. The image reading device according to claim 1, wherein the cover has a black and white reference portion provided on the back surface thereof, the black and white reference portion having a white portion and a black portion, the black and white reference portion being located on the opposite side of the opening in the sub-scanning direction, across the recess.

4. a control unit for controlling the reading sensor; The control unit determining an actual intersecting position where the first colored edge and the second colored edge intersect based on the result of reading the first colored edge and the second colored edge by the reading sensor; 3. The image reading device according to claim 1, wherein the reading range is corrected based on the actually measured intersection position.

5. the cover has a black-and-white reference portion provided on the rear surface, the black-and-white reference portion having a white portion and a black portion, the black-and-white reference portion being located on the opposite side of the recess from the opening in the sub-scanning direction, a control unit for controlling the reading sensor; the control unit stores information relating to a reference intersection position where the first colored edge and the second colored edge intersect, and a reference boundary position that is a boundary between the white portion and the black portion, The control unit determining a measured boundary position that is a boundary between the white portion and the black portion based on a result of reading the black and white reference portion by the reading sensor; determining an actual intersecting position where the first colored edge and the second colored edge intersect based on the result of reading the first colored edge and the second colored edge by the reading sensor; 3. The image reading device according to claim 1, wherein the reading range is corrected based on stored information about the reference intersection position and the reference boundary position and the determined actual measurement intersection position and the determined actual measurement boundary position.

6. The recess has an L-shaped profile, 3. The image reading device according to claim 1, wherein the first recessed edge and the second recessed edge form two sides located inside the L-shaped bend in the contour.

7. The cover is black or gray in color, 3. The image reading device according to claim 1, wherein the colored portion is white.

Images