JP2018181233A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect an edge image when reading a sheet member having unevenness. SOLUTION: A reading unit, a mat on which a sheet member is placed, a moving unit, a detection unit for detecting the sheet thickness, a height adjusting unit for changing the height position of the reading unit, and a control unit. The control unit determines whether or not the first thickness difference is equal to or less than the second distance, the detection process for detecting a plurality of sheet thicknesses of the sheet member, the first difference calculation process for calculating the first thickness difference, and the control unit. The lowest height among the height positions of the reading unit corresponding to the first range including all the plurality of sheet thicknesses when the first thickness difference determination process and the first thickness difference are the second distance or less. The first determination process for determining the position, the second determination process for determining the height position determined based on the minimum removal thickness when the first thickness difference is larger than the second distance, and the determined height position. Then, the reading process of generating an edge image by reading the sheet member is executed. [Selection diagram] FIG. 7

Description

  The present invention relates to an image reading apparatus.

  There is known an image reading apparatus for reading a sheet member by using a contact type image sensor by moving a platen on which the sheet member is placed.

  The image reading device described in Patent Document 1 reads the upper surface of the placed sheet member while moving the platen to the rear side in a state close to the upper surface side of the sheet member placed on the platen. Detect the pattern of

  Further, in the image reading apparatus described in Patent Document 2, when it is determined that the focal position changes depending on the thickness and type of the document to be read, the height of the contact type image sensor with respect to the contact glass through which the document passes Raise and lower.

JP, 2013-197935, A JP, 2009-223035, A

  As in the image reading apparatus described in Patent Document 2, when it is determined that the focal position changes depending on the thickness and type of the document, the platen on which the sheet member is placed is configured to raise and lower the height of the contact type image sensor. A case where the present invention is applied to an image reading apparatus described in Patent Document 1 that reads a sheet member by moving it will be considered.

  The image reading apparatus in this case reads the sheet member placed on the platen from above and detects an edge image from the read image of the sheet member. In order to detect an edge image, the image reading apparatus may adjust the height of the contact-type image sensor such that the position at which the distance between the contact-type image sensor and the sheet member is the shortest is in focus. However, in the case of a sheet member having a concavo-convex shape in which a plurality of materials are pasted on a cloth as a sheet member, when such a sheet member is read, the position where the distance between the contact image sensor and the sheet member is shortest. If the height of the contact image sensor is adjusted so that the image is in focus, only the convex portion at the highest position is in focus, and the other convex portions and concave portions are not in focus, and the edge image of the sheet member Problems occur that can not be detected.

  Therefore, the present invention has been made in view of the above-described circumstances, and an image reading apparatus capable of adjusting the height of the reading unit so that an edge image of the sheet member can be generated even when reading a sheet member having irregularities. Intended to provide.

  In order to achieve the above object, in the aspect of the invention according to claim 1, the image reading apparatus reads a sheet member to determine a reading unit that generates an edge image and a reference position in the height direction. A mat on which the member is placed, a moving unit that moves the mat to a position facing the reading unit in the transport direction orthogonal to the height direction, and a thickness of a sheet member placed on the mat in the height direction A detection unit that detects a certain sheet thickness, wherein the sheet thickness is a distance from the reference position to the upper end position of the sheet member in the height direction, and a height position of the reading unit in the height direction A height adjustment unit that changes in multiple steps in the height direction with respect to the reference position, and a control unit. The height adjustment unit is configured to adjust the height position of the reading unit in each of the multiple steps. Change one step To change the position of the reading unit in the height direction with respect to the reference position by a predetermined first distance, and the first range in which the reading unit reads with a resolution equal to or greater than a first predetermined value is the reference position Range of distances in the height direction with respect to each other, and a large number of them are determined respectively corresponding to the height positions of the multiple steps, and the focus ranges obtained by subtracting the lower limit of the first range from the upper limit of the first range are the same. A detection process for causing the detection unit to detect a plurality of sheet thicknesses of sheet members placed on the mat at a plurality of detection positions while moving the mat along the transport direction; A first difference calculation process for calculating a first thickness difference obtained by subtracting a first minimum thickness which is the thinnest thickness of the plurality of sheet thicknesses from a maximum thickness which is the thickest thickness of the plurality of sheet thicknesses; It is a first thickness difference judgment process of judging whether or not the first thickness difference is equal to or less than a second distance, wherein the second distance is a distance obtained by subtracting the first distance from the focus range. Thickness difference judgment processing, and when the first thickness difference is equal to or less than the second distance, the reading unit corresponding to a first range including all the plurality of sheet thicknesses in the plurality of first ranges From the plurality of sheet thicknesses, a first determination process of determining the height position of the reading unit at the lowest height position of the height positions, and when the first thickness difference is greater than the second distance A second determination process of determining the height position of the reading unit at a height position determined based on the minimum removal thickness excluding the first minimum thickness, and the first determination process or the second determination process At the determined height position, the height position of the reading unit is The reading unit causes the reading unit to generate an edge image by reading the sheet member placed on the mat and changing the height adjustment unit.

  In the specific aspect according to claim 2, the second determination processing calculates the number of thicknesses, which is the number of types of sheet thickness of the sheet member placed on the mat, from the plurality of sheet thicknesses. Processing, thickness number determination processing for determining whether or not the thickness number is 3 or more, and the maximum thickness is included in the plurality of first ranges when the thickness number is less than 3 A third determination process of determining the height position of the reading unit at the lowest height position among the height positions of the reading unit corresponding to one range; and when the number of thicknesses is 3 or more A fourth determination process of determining the height position of the reading unit at a height position determined based on a second thickness difference obtained by subtracting a second minimum thickness which is the thinnest thickness of the minimum removal thicknesses. And.

  In the specific aspect according to claim 3, the control unit calculates the number of positions for calculating the number of detected positions at which the sheet thickness is detected for each sheet thickness among the plurality of sheet thicknesses. A second difference calculation process of performing a process, wherein the fourth determination process calculates a second thickness difference obtained by subtracting the second minimum thickness from the maximum thickness; and the second thickness difference is equal to or less than the second distance A second thickness difference determination process for determining whether or not there is a first thickness difference, and when the second thickness difference is equal to or less than the second distance, all of the minimum removal thickness is included in the plurality of first ranges; A fifth determining process of determining the height position of the reading unit at the lowest height position among the height positions of the reading unit corresponding to the range; and when the second thickness difference is larger than the second distance The largest of the minimum removal thickness The height position registered number is determined based on the longest thickness is a sheet thickness calculated, including a sixth determination processing for determining the height position of the reading unit.

  In a specific aspect according to claim 4, a second range in which the reading unit reads with a resolution equal to or higher than a second predetermined value lower than the first predetermined value is a range of distance in the height direction with respect to the reference position. And a range which is wider than the first range and includes the first range, and is determined in correspondence with the multi-level height position respectively, and the sixth determining process is a longest process for determining the longest thickness. In the thickness determination processing, the first longest height position, which is the height position of the reading unit corresponding to the first range including the longest thickness among the plurality of first ranges, corresponds to the number of second ranges. A first thickness determination process of determining whether or not the height position of the reading unit corresponds to a second range in which the longest removed thickness excluding the longest removed thickness from the minimum removed thickness is all included; 1Maximum height position includes all of the longest removal thickness Height position of the reading unit corresponding to the second range, the height position of the reading unit corresponding to the second range including all the longest removal thicknesses among the first longest height position A seventh determining process of determining the height position of the reading unit at the lowest height position of the above, and the first longest height position corresponds to a second range in which the longest removal thickness is all included It is determined based on a second longest height position which is a height position of the reading unit corresponding to a second range including the longest thickness among the plurality of second ranges when the height position of the reading unit is not And an eighth determining process of determining the height position of the reading unit at the height position.

  In the specific aspect according to claim 5, in the eighth determination process, the second longest height position corresponds to a second range in which the longest removal thickness is all included in the plurality of second ranges. A second thickness determination process for determining whether or not the reading unit is at a height position, and a height of the reading unit corresponding to a second range in which the second longest height position includes all the longest removal thicknesses. When the reading position is the second maximum height position, the reading is performed at the lowest height position among the height positions of the reading unit corresponding to the second range in which the longest removal thickness is all included. A ninth determination process of determining the height position of the part, and when the second longest height position is not the height position of the reading part corresponding to a second range in which the longest removal thickness is all included; The second range at the height position of each of the reading portions of the two longest height positions A height position which is determined based on the total number of positions obtained by adding the number of positions corresponding to all of the thickness of the sheet contained in, including, a tenth decision process for determining the height position of the reading unit.

  In the specific aspect according to claim 6, the tenth determination process is performed on all sheet thicknesses included in the second range for the height position of the reading unit in the second longest height position. A total position number calculating process of calculating the total position number by adding the position number corresponding to the position position of the reading unit at which the largest total position number among the second longest height positions is calculated; And an eleventh determination process of determining a height position of the reading unit.

  In the aspect of the invention according to claim 1, the first difference calculation processing subtracts the first minimum thickness, which is the thinnest thickness among the plurality of sheet thicknesses, from the maximum thickness, which is the thickest thickness among the plurality of sheet thicknesses. Then, a first thickness difference is calculated. The first thickness difference determination process determines whether the first thickness difference is equal to or less than a second distance. In the first determination process, when the first thickness difference is equal to or less than the second distance, the height of the reading unit corresponding to the first range in which all the plurality of sheet thicknesses are included among the plurality of first ranges. The height position of the reading unit is determined at the lowest height position. In the second determination process, when the first thickness difference is larger than the second distance, the height position of the reading unit at the height position determined based on the minimum removal thickness obtained by removing the first minimum thickness from the plurality of sheet thicknesses. Decide. In the reading process, the height adjustment unit changes the height position of the reading unit to the height position determined in the first determination process or the second determination process, and the reading unit reads the sheet member placed on the mat. This causes the reading unit to generate an edge image. Therefore, when the first thickness difference, which is a case where the thickness variation of the sheet member is small, is equal to or less than the second distance, among the height positions of the reading unit corresponding to the first range including all the plurality of sheet thicknesses. When the first thickness difference is larger than the second distance, which is a case where the thickness of the sheet member has a large variation, it is determined based on the minimum removal thickness excluding the first minimum thickness. In order to determine the height position of the reading unit at the height position, an edge image of the sheet member can be generated even when the sheet member having the unevenness is read.

  In the specific aspect of the second aspect, the thickness number calculation process calculates the number of thicknesses, which is the number of types of sheet thickness of the sheet member placed on the mat, from the plurality of sheet thicknesses. In the thickness number determination process, it is determined whether the thickness number is 3 or more. In the third determination process, when the number of thicknesses is less than 3, at the lowest height position among the height positions of the reading unit corresponding to the first range including the largest thickness among the plurality of first ranges. , Determine the height position of the reading unit. The fourth determination processing is performed at a height position determined based on a second thickness difference obtained by subtracting a second minimum thickness which is the thinnest thickness among the minimum removal thicknesses when the thickness number is 3 or more. , Determine the height position of the reading unit. Therefore, when the number of thicknesses is less than 3, since there are only two types of thickness, the height of the reading unit is at the lowest height position among the height positions corresponding to the first range including the maximum thickness. By determining the height position, it is possible to reliably detect the edge image of the convex portion with the maximum thickness.

  According to the specific aspect of the present invention, the position number calculation process calculates the number of positions which is the number of detection positions at which each sheet thickness is detected for each sheet thickness among the plurality of sheet thicknesses. The second difference calculation process calculates a second thickness difference obtained by subtracting the second minimum thickness from the maximum thickness. The second thickness difference determination process determines whether the second thickness difference is equal to or less than a second distance. In the fifth determination process, when the second thickness difference is equal to or less than the second distance, the height position of the reading unit corresponding to the first range in which all the minimum removal thicknesses are included among the plurality of first ranges. The height position of the reading unit is determined at the lowest height position. The sixth determination process reads the height position determined based on the longest thickness, which is the calculated sheet thickness, when the second thickness difference is larger than the second distance, and the largest number of positions among the minimum removal thickness is calculated. Determine the height position of the department. Therefore, when there are a plurality of convex portions attached to the sheet member where the second thickness difference is equal to or less than the second distance, and the difference in thickness of the plurality of convex portions is small, all of the plurality of convex portions If there are a plurality of convex portions attached to the sheet member which can detect an edge image and the second thickness difference is larger than the second distance, and if the difference in thickness of the plurality of convex portions is large, The edge image of the convex part of the longest thickness can be detected among the convex parts.

  In a specific aspect according to claim 4, the longest thickness determination process determines the longest thickness. In the first thickness determination process, the first longest height position, which is the height position of the reading unit corresponding to the first range including the longest thickness among the plurality of first ranges, is included in the plurality of second ranges. It is determined whether or not the height position of the reading unit corresponds to the second range including all of the longest removal thicknesses excluding the minimum removal thickness and the longest removal thickness. In the seventh determination processing, when the first longest height position is the height position of the reading unit corresponding to the second range in which all the longest removed thicknesses are included, the longest removed thickness among the first longest height positions The height position of the reading unit is determined at the lowest height position among the height positions of the reading unit that corresponds to the second range in which all are included. The eighth determination process includes the longest thickness among the plurality of second ranges when the first longest height position is not the height position of the reading unit corresponding to the second range in which the longest removal thickness is all included. The height position of the reading unit is determined at the height position determined based on the second longest height position, which is the height position of the reading unit corresponding to the second range. Therefore, the first longest height position in which the convex portion with the longest thickness is included in the first range among the plurality of convex portions corresponds to the second range in which the remaining convex portions other than the convex portion with the longest thickness are included When the height position is determined, the height position of the reading unit is determined at the lowest height position of the first longest height position, thereby to generate edge images of a plurality of convex portions attached to the sheet member. Can be detected.

  In a specific aspect according to claim 5, in the second thickness determination process, the second longest height position corresponds to a second range in which the longest removal thickness is all included in a large number of second ranges. It is determined whether or not it is a height position. In the ninth determination process, when the second longest height position is at the height position of the reading unit corresponding to the second range including all the longest removal thicknesses, the longest removal thickness among the second longest height positions The height position of the reading unit is determined at the lowest height position among the height positions of the reading unit that corresponds to the second range in which all are included. In the tenth determination processing, when the second longest height position is not the height position of the reading unit corresponding to the second range in which the longest removal thickness is all included, each reading unit of the second longest height position The height position of the reading unit is determined at the height position determined based on the total number of positions obtained by adding the number of positions corresponding to all sheet thicknesses included in the second range at the height position of. Therefore, the second longest height position in which the convex portion with the longest thickness is included in the second range among the plurality of convex portions corresponds to the second range in which the remaining convex portions other than the convex portion with the longest thickness are included If the height position is the lowest position of the second longest height position, the height position of the reading unit is determined to determine the edge images of the plurality of convex portions attached to the sheet member. It can be detected.

  In the specific aspect according to the sixth aspect, the total position number calculation processing is a position corresponding to all sheet thicknesses included in the second range with respect to the height position of each reading unit among the second longest height positions. Calculate the total number of positions by adding numbers. The eleventh determination process determines the height position of the reading unit at the height position of the reading unit where the largest total number of positions among the second longest height positions is calculated. Therefore, among the plurality of convex portions, among the second longest height positions in which the convex portion with the longest thickness is included in the second range, the remaining convex portions other than the convex portion with the longest thickness included in the second range are detected By determining the height position of the reading unit at the height position where the number of detected positions is the largest, it is possible to detect edge images of a plurality of convex portions attached to the sheet member.

It is drawing which shows the internal structure from the main scanning direction MS of the image reader 1 which concerns on embodiment of this invention. It is drawing which shows the internal structure from height direction HD of the image reader 1 which concerns on embodiment of this invention. It is drawing explaining the height position of the reading part 17 from the 1st position P1 to the 6th position P6, 1st range PR1, and 2nd range PR2. FIG. 2 is a block diagram showing an electrical configuration of the image reading apparatus 1; It is a flowchart which shows a cutting process. It is a flow chart which shows thickness detection processing C2. It is a flow chart which shows height position HGP decision processing C3. It is a flowchart which shows height position HGP determination processing CB6 based on the thickness number TN. It is a flowchart which shows height position HGP determination processing CC4 based on thickness other than the minimum thickness MNT. It is a flowchart which shows height position HGP determination processing CD4 based on 1st thickness TN1. FIG. 11A is a view showing the specific sheet member SM1. FIG. 11B is a drawing showing the result of detecting the height of the specific sheet member SM1. FIG. 11C is a drawing showing a histogram of the height detection result of the specific sheet member SM1.

<Configuration of Image Reading Device 1>
The image reading apparatus 1 will be described with reference to FIGS. 1 and 2. The image reading apparatus 1 reads an image on the upper surface of a sheet member such as cloth or paper, and then inputs a cutting position at which the user cuts the sheet member while looking at the image read by the user. The apparatus is equipped with a cutting function to cut. FIG. 1 is an internal block diagram from the main scanning direction MS of the image reading apparatus 1, and FIG. 2 is an internal block diagram from a height direction HD. In FIG. 1, the height direction HD and the transport direction TD are directions indicated by arrows, and in FIG. 2, the transport direction TD and the main scanning direction MS are directions indicated by arrows. The image reading device 1 of the present embodiment shown in FIGS. 1 and 2 includes a main body MB and a mat 40. The touch panel 80 is disposed on the upper surface of the main body MB. The touch panel 80 includes the display unit 16 and the operation unit 15. The operation unit 15 receives a start operation for starting a cutting process described later, a cutting position input operation for inputting a cutting position to be cut from an edge image read in a reading process described later, and the like. The display unit 16 displays the edge image read in the reading process.

  A transport path 50 is formed inside the main body MB. The sheet member SM placed on the mat 40 is transported in the transport direction TD along the transport path 50 while being placed on the mat 40. The height detection roller 51, the conveyance rollers 52 and 53, the mat sensor 21, the cutting unit 90, and the reading unit 17 are disposed along the conveyance path 50.

  The mat 40 includes a reference portion BP which is a reference position BPH in the height direction HD. The height detection roller 51 is biased downward in the height direction HD and moves up and down in the height direction HD according to the thickness of the sheet member SM placed in the thickness detection area HDR of the mat 40. The height detection sensor 23 detects the thickness of the sheet member SM placed on the mat 40 by detecting the position of the height detection roller 51 in the height direction HD. The transport rollers 52 and 53 are driven by the transport motor MT2. The transport rollers 52 and 53 transport the mat 40 such that the sheet member SM placed on the mat 40 faces the cutting unit 90 and the reading unit 17. The mat sensor 21 detects the leading end position of the mat 40. In the present embodiment, since the thickness of the sheet member SM placed on the mat 40 can be placed to “3.0 mm”, the height upper limit position HULP of the sheet member SM is “3. It is 0 mm. Here, the thickness of the sheet member SM is the distance from the position of the upper end of the sheet member SM when the height detection roller 51 biases the sheet member SM downward in the height direction HD to the reference position BPH.

  The image reading device 1 according to the present embodiment includes a cutting unit 90 and a reading unit 17 between the conveyance roller 52 and the conveyance roller 53. The cutting unit 90 is configured to be movable in the height direction HD and the main scanning direction MS, and cuts the sheet member SM placed on the mat 40.

  The reading unit 17 includes a light source 31, a light receiving unit 32, a rod lens 33, and a platen glass 34. The platen glass 34 is made of a transparent plate-like glass. When the light emitted from the light source 31 is reflected by the reading surface of the sheet member SM or the like, the rod lens 33 focuses the reflected light transmitted through the platen glass 34 on the light receiving unit 32. The light source 31 includes a light emitting diode of one chip provided with light emitting diodes of three colors of red, green and blue and a light guide for guiding light from the light emitting diode in the main scanning direction MS. The height adjustment mechanism MM is connected to the reading unit 17, receives a drive from the height adjustment motor MT1 (see FIG. 4), and moves the reading unit 17 from the first position P1 to the sixth position P6 in the height direction HD. Move up and down in six steps.

  The positions in the height direction HD from the first position P1 to the sixth position P6 and the first range PR1 and the second range PR2 which are ranges of the focal length of the reading unit 17 will be described with reference to FIG. 3. . In the present embodiment, the first range PR1 is a range in which the reading unit 17 has an MTF (abbreviation of Modulation Transfer Function) of 30% or more with respect to the resolution of 300 DPI. The second range PR2 is a range in which the reading unit 17 has an MTF of 30% or more with respect to the resolution of 150 DPI. In the present embodiment, for example, the MTF for the resolution of 300 DPI is calculated from digital data when the rectangular wave chart having the resolution of 300 DPI is read.

  The first position P1 is determined such that “0.10 mm”, which is the thickness of the thinnest sheet member SM readable by the image reading apparatus 1 of the present embodiment, is the lower limit value of the first range PR1. Therefore, when the reading unit 17 is at the first position P1, the first range PR1 is a range from “0.10 mm” to “0.90 mm” above the height direction HD with the reference position BPH as a base point, The second range PR2 is a range from “0.00 mm” to “1.15 mm” above the height direction HD with the reference position BPH as a base point.

  The second position P2 is “0.4 mm” above the first position P1 in the height direction HD. When the reading unit 17 is at the second position P2, the first range PR1 is a range from “0.50 mm” to “1.30 mm” above the height direction HD with the reference position BPH as a base point. The range PR2 is a range from “0.25 mm” to “1.55 mm” above the height direction HD with the reference position BPH as a base point.

  The third position P3 is “0.4 mm” above the second position P2 in the height direction HD. When the reading unit 17 is at the third position P3, the first range PR1 is a range from “0.90 mm” to “1.70 mm” above the height direction HD with the reference position BPH as a base point. The range PR2 is a range from “0.65 mm” to “1.95 mm” above the height direction HD with the reference position BPH as a base point.

  The fourth position P4 is a position “0.4 mm” above the third position P3 in the height direction HD. When the reading unit 17 is at the fourth position P4, the first range PR1 is a range from “1.30 mm” to “2.10 mm” above the height direction HD with the reference position BPH as a base point. The range PR2 is a range from “1.05 mm” to “2.35 mm” above the height direction HD with the reference position BPH as a base point.

  The fifth position P5 is a position “0.4 mm” above the fourth position P4 in the height direction HD. When the reading unit 17 is at the fifth position P5, the first range PR1 is a range from “1.70 mm” to “2.50 mm” above the height direction HD with the reference position BPH as a base point. The range PR2 is a range from “1.45 mm” to “2.75 mm” above the height direction HD with the reference position BPH as a base point.

  The sixth position P6 is “0.4 mm” above the fifth position P5 in the height direction HD. When the reading unit 17 is at the sixth position P6, the first range PR1 is a range from “2.10 mm” to “2.90 mm” above the height direction HD with the reference position BPH as a base point. The range PR2 is a range from “1.85 mm” to “3.00 mm” above the height direction HD with the reference position BPH as a base point.

<Electric Configuration of Image Reading Device 1>
The electrical configuration of the image reading apparatus 1 will be described with reference to FIG. In FIG. 4, the image reading apparatus 1 includes a CPU 11, a ROM 12, a RAM 13, a flash PROM 14, a device control unit 22, an image processing unit 29, an analog front end (hereinafter referred to as AFE) 28, and a drive circuit 18 as main components. Prepare. These components are connected to the operation unit 15, the display unit 16, the mat sensor 21, the height detection sensor 23, and the cutting unit 90 via the bus 24.

  The ROM 12 stores programs for executing various operations of the image reading apparatus 1 such as cutting processing to be described later and processing of a subroutine during cutting processing. The CPU 11 controls each unit in accordance with the program read from the ROM 12. The flash PROM 14 is a readable and writable non-volatile memory, and stores various data set by control processing of the CPU 11, for example, each data used when initializing. The RAM 13 temporarily stores calculation results and the like generated by control processing of the CPU 11.

  The device control unit 22 is connected to the reading unit 17 and transmits to the light source 31 a signal for controlling turning on or off of the light source 31 and a signal for controlling a current value flowing to the light source 31 based on an instruction from the CPU 11. The device control unit 22 also transmits a signal for controlling the light receiving unit 32 to the light receiving unit 32. When the reading unit 17 receives these signals from the device control unit 22, the reading unit 17 turns on the light source 32 and transmits an analog signal according to the amount of light received by the light receiving unit 32 to the AFE 28.

  The AFE 28 is connected to the reading unit 17, converts an analog signal transmitted from the reading unit 17 into digital data based on an instruction from the CPU 11, and transmits the converted digital data to the image processing unit 29. The image processing unit 29 performs edge detection processing on digital data based on an instruction from the CPU 11, generates an edge image, and stores the edge image in the RAM 13.

  The drive circuit 18 is connected to the height adjustment motor MT1 and the conveyance motor MT2, and drives the height adjustment motor MT1 and the conveyance motor MT2 based on a drive command transmitted from the CPU 11. The drive circuit 18 rotates the height adjustment motor MT1 in accordance with the rotation amount and the rotation direction instructed by the drive instruction. When the height adjustment motor MT1 rotates by a first predetermined amount, the height adjustment mechanism MM switches driving, and the reading unit 17 is moved in the height direction HD by a first predetermined distance. The drive circuit 18 rotates the transport motor MT2 along the rotation amount and the rotation direction instructed by the drive instruction. When the transport motor MT2 rotates by a second predetermined amount, the transport rollers 52 and 53 rotate by a predetermined angle, and the mat 40 is transported by a second predetermined distance in the transport path 50.

<Operation of Image Reading Device 1>
(Cutting process)
Next, the operation of the image reading apparatus 1 will be described with reference to the drawings. The image reading apparatus 1 mainly executes a cutting process for cutting the sheet member SM. Processes C1 to C5 in the cutting process shown in FIG. 5 are processes executed by the CPU 11.

  The cutting process illustrated in FIG. 5 is started by the user performing the start operation with the operation unit 15 in a state where the mat 40 on which the sheet member SM is placed is abutted against the transport roller 52 and the height detection roller 51. Ru. That is, when the CPU 11 receives an instruction to start the cutting process from the operation unit 15, the CPU 11 starts the cutting process.

  The CPU 11 initializes the device control unit 22, the AFE 28, the image processing unit 29, the drive circuit 18, and the cutting unit 90 (C1). Specifically, the CPU 11 sets setting values necessary for the cutting process in the device control unit 22, the AFE 28, the image processing unit 29, the drive circuit 18, and the cutting unit 90.

  The CPU 11 detects the thickness of the sheet member SM placed on the mat 40 (C2). Details will be outlined here, as will be described later. The CPU 11 acquires the reference position BPH by causing the height detection sensor 23 to detect the position in the height direction HD of the reference portion BP of the mat 40. The CPU 11 acquires the thickness of the sheet member SM in the thickness detection area HDR of the mat 40 at intervals of “1 mm” in the conveyance direction TD while conveying the mat 40 in the conveyance direction TD. In the present embodiment, the thickness of the sheet member SM is the distance from the reference position BPH to the upper end position of the highest sheet member SM in the main scanning direction MS.

  The CPU 11 determines the height position HGP which is the position in the height direction HD of the reading unit 17 when executing the reading process C4 described later (C3). Details will be outlined here, as will be described later. The CPU 11 performs peak detection of the number of detections of each thickness with respect to the thickness of the sheet member SM in the thickness detection area HDR acquired in the processing C2, and creates each thickness and the number of detections of each thickness as a histogram. The CPU 11 calculates the first thickness difference TDF1 which is a value obtained by subtracting the thinnest minimum thickness MNT from the thickest maximum thickness MXT, the number TN of thicknesses which is the number of types of each thickness, and the minimum thickness MNT from each thickness. The height position HGP is determined based on the second thickness difference TDF2.

  The CPU 11 moves the reading unit 17 to the height position HGP to read the sheet member SM (C4). Specifically, the CPU 11 transmits a drive command to drive the height adjustment motor MT1, thereby moving the reading unit 17 to the height position HGP determined in the process C3. The CPU 11 causes the reading unit 17 to read the thickness detection area HDR of the mat 40 to acquire an edge image of the sheet member SM.

  The CPU 11 causes the cutting unit 90 to cut the sheet member SM (C5). Specifically, the CPU 11 causes the display unit 16 to display the edge image read in process C4. The CPU 11 causes the cutting unit 90 to cut the sheet member SM while conveying the mat 40 according to the cutting position input through the operation unit 15 by the cutting position input operation. When the process C5 ends, the disconnection process ends.

(Thickness detection processing C2)
When the thickness detection process C2 shown in FIG. 6 is started, the CPU 11 starts the conveyance operation of the mat 40 (CA1). Specifically, the CPU 11 transmits a drive command to the drive circuit 18, and starts the transport operation of transporting the mat 40 on which the sheet member SM is mounted in the transport direction TD.

  The CPU 11 determines whether the mat sensor 21 is on (CA2). The CPU 11 proceeds to processing CA3 when the mat sensor 21 is on (CA2: Yes), and continues the transport operation of the mat 40 when the mat sensor 21 is not on (CA2: No).

  The CPU 11 sets the position of the mat 40 in the transport direction TD (CA3). Specifically, when the mat sensor 21 is turned on, the CPU 11 determines that the front end of the mat 40 is positioned at the position of the mat sensor 21 in the transport direction TD, and the position of the reference portion BP in the transport direction TD; The transfer direction TD and the range of the thickness detection area HDR in the main scanning direction MS are set in the RAM 13. In the present embodiment, the range of the thickness detection area HDR in the main scanning direction MS is a predetermined range, and is a range determined based on the largest sheet member SM that can be placed on the mat 40.

  The CPU 11 transmits a drive command to the drive circuit 18, and transports the reference portion BP of the mat 40 to the position of the height detection roller 51 in the transport direction TD (CA4).

  The CPU 11 acquires the reference position BPH of the mat 40 (CA5). Specifically, the CPU 11 uses the position in the height direction HD detected by the height detection sensor 23 as the reference position BPH in a state where the reference portion BP of the mat 40 is at the position of the height detection roller 51 in the transport direction TD. get.

  The CPU 11 transmits the drive command to the drive circuit 18, and conveys the mat 40 so that the leading end position of the thickness detection area HDR of the mat 40 in the conveyance direction TD becomes the position of the height detection roller 51 in the conveyance direction TD (CA6) ).

  The CPU 11 starts a thickness detection operation of detecting the thickness of the sheet member SM placed in the thickness detection area HDR of the mat 40 (CA7). Specifically, the CPU 11 transmits a drive command to the drive circuit 18, and transports the mat 40 in the transport direction TD, and is placed in the thickness detection area HDR of the mat 40 at an interval of 1 mm in the transport direction TD. The thickness detection operation for detecting the thickness of the sheet member SM is started.

  The CPU 11 determines whether or not the rear end position of the thickness detection area HDR of the mat 40 in the transport direction TD is at the position of the height detection roller 51 (CA8). The CPU 11 continues the thickness detection operation when the rear end position of the thickness detection area HDR of the mat 40 in the transport direction TD is not at the position of the height detection roller 51 (CA8: No), and the mat 11 in the transport direction TD. When the rear end position of the thickness detection area HDR is at the position of the height detection roller 51 (CA8: Yes), the standard among the thicknesses of the sheet members SM from the front end position to the rear end position of the thickness detection area HDR of the mat 40 The thickness of the sheet member SM at “1 mm” intervals in the transport direction TD excluding the position BPH is stored in the RAM 13. When the process CA8 ends, the thickness detection process C2 ends. In the present embodiment, the thickness of the sheet member SM is a distance from the reference position BPP to the upper end position of the sheet member SM.

(Height position HGP determination process C3)
When the height position HGP determination process C3 shown in FIG. 7 is started, the CPU 11 creates a histogram of the thickness of the sheet member SM (CB1). Specifically, the CPU 11 detects the peak of the number of detections of each thickness with respect to the thickness of the sheet member SM at an interval of "1 mm" in the transport direction TD from the leading end position to the rear end position of the thickness detection area HDR Perform detection. That is, the CPU 11 sets the thickness from “0.10 mm” to “0.14 mm” as the thickness of “0.10 mm”, and counts the number of detected thicknesses included in “0.10 mm”. The CPU 11 sets the thickness from “0.15 mm” to “0.24 mm” as “0.20 mm”, and counts the number of detected thicknesses included in “0.2 mm”. Hereinafter, the CPU 11 repeatedly executes the process every “0.1 mm”, and the CPU 11 sets the thickness from “2.95 mm” to “3.00 mm” as the “3.00 mm” thickness, and the thickness included in “3.00 mm” Count the number of detections. The CPU 11 associates each thickness of “0.10 mm” with the detected number of each thickness, and stores it in the RAM 13. In the present embodiment, each thickness is a thickness from “0.10 mm” to “3.00 mm”. The number of detections is the number obtained by totaling the number of positions at which each thickness was detected. For example, the number of detections for the thickness of “0.2 mm” detected the thickness from “0.15 mm” to “0.24 mm” It is the total number of positions.

  The CPU 11 extracts the minimum thickness MNT and the maximum thickness MXT (CB2). Specifically, the CPU 11 extracts the thinnest thickness from the thicknesses stored in the RAM 13 as the minimum thickness MNT, and extracts the thickest thickness from the thicknesses stored in the RAM 13 as the maximum thickness MXT.

  The CPU 11 calculates a first thickness difference TDF1 (CB3). Specifically, the CPU 11 subtracts the minimum thickness MNT from the maximum thickness MXT to calculate a first thickness difference TDF1.

  The CPU 11 determines whether the first thickness difference TDF1 is "0.4 mm" or less (CB4). The CPU 11 proceeds to the process CB6 when the first thickness difference TDF1 is larger than “0.4 mm” (CB4: No), and when the first thickness difference TDF1 is “0.4 mm or less” (CB4: Yes) Proceed to process CB5. In the present embodiment, the distance between each adjacent position in the height direction HD from the first position P1 to the sixth position P6 is “0.4 mm”. The focus range, which is a value obtained by subtracting the lower limit value of the first range PR1 from the upper limit value of the first range PR1, is “0.8 mm”. Therefore, “0.4 mm”, which is used as the determination reference for the first thickness difference TDF1 in the process CB4, is “0.4 mm”, which is the distance between each adjacent position from “0.8 mm” which is the focus range of the first range PR1. "0.4 mm" is calculated by subtracting "."

  The CPU 11 determines the height position HGP based on the minimum thickness MNT and the maximum thickness MXT (CB5). Specifically, the CPU 11 determines the lowest position among the first position P1 to the sixth position P6 where the minimum thickness MNT and the maximum thickness MXT are the first range PR1 as the height position HGP. When the process CB5 ends, the process C3 ends.

  If it is determined No in the process CB4, the CPU 11 determines the height position HGP based on the thickness number TN (CB6). Details will be outlined here, as will be described later. The CPU 11 calculates the thickness number TN. The CPU 11 determines whether the thickness number TN is "3" or more, and determines the height position HGP based on the maximum thickness MXT when the thickness number TN is less than "3", and the thickness number TN is When it is "3" or more, the height position HGP is determined based on the thickness other than the minimum thickness MNT. When the process CB6 ends, the process C3 ends. In the present embodiment, “3”, which is the reference of the determination of the process CB6, is a numerical value for determining whether the number of the materials attached to the sheet member SM is one or less. That is, when the thickness number TN is less than "3", the number of the materials attached to the sheet member SM is one or less.

(Height position HGP determination processing CB6 based on thickness number TN)
When the height position HGP determination process CB6 based on the thickness number TN shown in FIG. 8 is started, the CPU 11 counts the thickness number TN (CC1). Specifically, the CPU 11 counts the number of types of each thickness from each thickness stored in the RAM 13 as the number TN of thicknesses.

  The CPU 11 determines whether the thickness number TN is “3” or more (CC2). The CPU 11 proceeds to the process CC4 when the thickness number TN is "3" or more (CC2: Yes), and proceeds to the process CC3 when the thickness number TN is less than "3" (CC2: No).

  The CPU 11 determines the height position HGP based on the maximum thickness MXT (CC3). Specifically, the CPU 11 determines the lowest position among the positions from the first position P1 to the sixth position P6 where the maximum thickness MXT is the first range PR1 as the height position HGP. When the process CC3 ends, the process CB6 ends.

  If it is judged as Yes in process CC2, CPU11 will determine height position HGP by thickness other than the minimum thickness MNT (CC4). Details will be outlined here, as will be described later. The CPU 11 calculates a second thickness difference TDF2. The CPU 11 determines whether or not the second thickness difference TDF2 is "0.4 mm" or less, and when the second thickness difference TDF2 is larger than "0.4 mm", the height is based on a thickness other than the minimum thickness MNT. The position HGP is determined, and when the second thickness difference TDF2 is "0.4 mm" or less, the height position HGP is determined by the integrated distance AL in the transport direction TD. When the process CC4 ends, the process CB6 ends.

(Height determination process CC4 by thickness other than minimum thickness MNT CC4)
When the height position HGP determination processing CC4 with a thickness other than the minimum thickness MNT shown in FIG. 9 is started, the CPU 11 calculates the second thickness difference TDF2 excluding the minimum thickness MNT (CD1). Specifically, a second thickness difference TDF2 is calculated by subtracting the second smallest thickness among the thicknesses stored in the RAM 13 from the maximum thickness MXT.

  The CPU 11 determines whether the second thickness difference TDF2 is "0.4 mm" or less (CD2). The CPU 11 proceeds to the processing CD3 when the second thickness difference TDF2 is "0.4 mm" or less (CD2: Yes), and when the second thickness difference TDF2 is larger than "0.4 mm" (CD2: No) , Proceed to process CD4. In the present embodiment, the distance between each adjacent position in the height direction HD from the first position P1 to the sixth position P6 is “0.4 mm”. The focus range, which is a value obtained by subtracting the lower limit value of the first range PR1 from the upper limit value of the first range PR1, is “0.8 mm”. Therefore, “0.4 mm”, which is used as the determination reference for the second thickness difference TDF2 in the processed CD2, is “0.4 mm,” which is the distance between each adjacent position from “0.8 mm” which is the focus range of the first range PR1. "0.4 mm" is calculated by subtracting "."

  The CPU 11 determines the height position HGP based on the thickness other than the minimum thickness MNT (CD3). Specifically, the CPU 11 sets the lowest position among the positions from the first position P1 to the sixth position P6 in which all the thicknesses excluding the minimum thickness MNT among the thicknesses stored in the RAM 13 are the first range PR1. Is determined as the height position HGP. When the process CD3 ends, the process CC4 ends.

  If it is determined No in the processing CD2, the CPU 11 determines the height position HGP based on the first thickness TN1 (CD4). Details will be outlined here, as will be described later. The CPU 11 extracts the first thickness TN1. The CPU 11 extracts a first height position candidate HGPP1 in which the first thickness TN1 is in the first range PR1. The CPU 11 extracts a second height position candidate HGPP2 in which the first thickness TN1 is in the second range PR2. The CPU 11 sets a thickness group TNG. The CPU 11 determines whether or not there is a position where all the thickness groups TNG fall within the second range PR2 among the first height position candidates HGPP1. The CPU 11 determines the height position HGP based on the first height position candidate HGPP1 when there is a position where all the thickness groups TNG are in the second range PR2 among the first height position candidate HGPP1 and determines the first height If there is no position where thickness group TNG is all within second range PR2 among height position candidates HGPP1, whether or not there is a position where all thickness groups TNG become second range PR2 among second height position candidates HGPP2 To judge. The CPU 11 determines the height position HGP based on the second height position candidate HGPP2 when there is a position where the thickness group TNG is all within the second range PR2 among the second height position candidate HGPP2 and determines the second height In the case where there is no position where the thickness group TNG is all within the second range PR2 among the height position candidates HGPP2, the integrated distance AL is calculated for each position of the second height position candidate HGPP2. The CPU 11 determines the height position HGP based on the integration distance AL. When the process CD4 ends, the process CC4 ends.

(Height position HGP determination processing CD4 based on the first thickness TN1)
When the height position HGP determination processing CD4 based on the first thickness TN1 shown in FIG. 10 is started, the CPU 11 extracts the first thickness TN1 (CE1). Specifically, the CPU 11 extracts the thickness associated in the process CB1 with the largest detection number among the thicknesses obtained by removing the minimum thickness MNT from the respective thicknesses stored in the RAM 13 as a first thickness TN1.

  The CPU 11 extracts the first height position candidate HGPP1 (CE2). Specifically, the CPU 11 extracts the positions from the first position P1 to the sixth position P6 where the first thickness TN1 is the first range PR1 as the first height position candidate HGPP1.

  The CPU 11 extracts the second height position candidate HGPP2 (CE3). Specifically, the CPU 11 extracts the positions from the first position P1 to the sixth position P6 where the first thickness TN1 is the second range PR2 as the second height position candidate HGPP2.

  The CPU 11 extracts the thickness group TNG (CE4). Specifically, the CPU 11 extracts the thickness excluding the minimum thickness MNT and the first thickness TN1 among the thicknesses stored in the RAM 13 as a thickness group TNG.

  The CPU 11 determines whether or not there is a position from the first position P1 to the sixth position P6 where the thickness group TNG is all within the second range PR2 among the first height position candidates HGPP1 (CE5). The CPU 11 proceeds to the process CE 6 when there is a position from the first position P 1 to the sixth position P 6 where all the thickness groups TNG are in the second range PR 2 among the first height position candidate HGPP 1 (CE 5: Yes) . The CPU 11 proceeds to the process CE7 when there is no position from the first position P1 to the sixth position P6 where the thickness group TNG is all the second range PR2 among the first height position candidate HGPP1 (CE5: No) .

  The CPU 11 determines the height position HGP based on the first height position candidate HGPP1 (CE6). Specifically, the CPU 11 sets the height of the lowest position among the positions from the first position P1 to the sixth position P6 where the thickness group TNG is all the second range PR2 in the first height position candidate HGPP1. Determined as position HGP. When the process CE6 ends, the process CD4 ends.

  If it is determined No in the processing CE5, the CPU 11 determines whether or not there is a position from the first position P1 to the sixth position P6 where the thickness group TNG is all the second range PR2 among the second height position candidates HGPP2 Determine whether the (CE7). The CPU 11 proceeds to processing CE8 when there is a position from the first position P1 to the sixth position P6 where the thickness group TNG is all the second range PR2 among the second height position candidates HGPP2 (CE7: Yes) . The CPU 11 proceeds to processing CE 9 when there is no position from the first position P 1 to the sixth position P 6 where all the thickness groups TNG are the second range PR 2 among the second height position candidates HGPP 2 (CE 7: No) .

  The CPU 11 determines the height position HGP based on the second height position candidate HGPP2 (CE8). Specifically, the CPU 11 sets the height of the lowest position among the positions from the first position P1 to the sixth position P6 where the thickness group TNG is all the second range PR2 in the second height position candidate HGPP2 Determined as position HGP. When the process CE8 ends, the process CD4 ends.

  If it is determined No in the process CE7, the CPU 11 is associated in the process CB1 with all thicknesses included in the second range PR2 of the thickness group TNG at each height position of the second height position candidate HGPP2. The integrated distance AL is calculated by adding all the detected numbers (CE 9). In the present embodiment, the integrated distance AL is calculated for each height position of the second height position candidate HGPP2.

  The CPU 11 determines the height position HGP based on the integration distance AL (CE10). Specifically, the CPU 11 heights the height position at which the largest integration distance AL is calculated among the integration distances AL calculated for each height position of the second height position candidates HGPP2. Determined as position HGP. When the process CE10 ends, the process CD4 ends.

(Concrete example)
Next, the process of determining the height position HGP when reading the specific sheet member SM1 will be described with reference to FIG. The specific sheet member SM1 shown in FIG. 11A has an elliptical first patch PT1 and a second patch PT2 on the upper surface of a rectangular cloth having a width of 127 mm in the main scanning direction MS and 254 mm in the transport direction TD. Is the sheet member stuck.

  The detection result from the front end position of the specific sheet member SM1 to the rear end position when the thickness detection process is performed on the specific sheet member SM1 is shown in FIG. The first patch PT1 has a thickness of “1.6 mm” and a length of 73 mm in the transport direction TD, so the number of detections is “73” as the detection result of the “1 mm” interval. The second patch PT2 has a thickness of "2.2 mm" and a length of 37 mm in the transport direction TD, so the number of detections is "37" as the detection result of the "1 mm" interval. The remaining cloth portion has a thickness of "1.2 mm" and the length in the transport direction TD is 144 mm excluding 254 mm to 73 mm and 37 mm. Therefore, as the detection result of the "1 mm" interval, the number of detections is It is "144". Therefore, the histogram of the specific sheet member SM1 is as shown in FIG. In the present embodiment, the thickness of “1.6 mm”, the thickness of “2.2 mm”, and the thickness of “1.2 mm” are examples of the respective thicknesses.

  In the process CB3, the first thickness difference TDF1 is calculated as "1.0 mm" by subtracting "1.2 mm" which is the minimum thickness MNT from "2.2 mm" which is the maximum thickness MXT. Since the first thickness difference TDF1 is larger than "0.4 mm", it is determined No in the process CB4 and the process CB6 is executed.

  In the treatment CC1 of the treatment CB6, the thickness number TN is counted as "3" because the thickness type is three types of "1.6 mm", "2.2 mm", and "1.2 mm" Be done. Since the thickness number TN is “3”, it is determined as Yes in the process CC2, and the process CC4 is executed.

  In the treatment CD1 of the treatment CC4, the second thinnest thickness “1.6 mm” is subtracted from the maximum thickness MXT “2.2 mm” to calculate “0.6 mm” as the second thickness difference TDF2. Do. Since 2nd thickness difference TDF2 is larger than "0.4 mm", it is judged as No in process CD2, and process CD4 is performed.

  In the treatment CE1 of the treatment CD4, "1.6 mm", which is the thickness associated in the treatment CB1 with "73", which is the largest detection number among the thicknesses excluding the minimum thickness MNT, "1.2 mm" Is extracted as a first thickness TN1. In the processing CE2, the third position P3 and the fourth position P4 which are positions where “1.6 mm” is included in the first range PR1 are extracted as the first height position candidate HGPP1. In processing CE3, the third position P3, the fourth position P4, and the fifth position P5, which are positions where “1.6 mm” is included in the second range PR2, are extracted as the second height position candidate HGPP2. In the treatment CE4, among the “1.2 mm”, “1.6 mm” and “2.2 mm”, the minimum thickness MNT “1.2 mm” and the first thickness TN1 “1.6 mm” "2.2 mm" except for is extracted as thickness group TNG. In processing CE5, since there is a height position where “2.2 mm” which is the thickness group TNG in the first height position candidate HGPP1 is the second range PR2, Yes is determined in processing CE5, and processing CE6 is executed. Ru. In the processing CE6, the fourth position P4 in which the thickness group TNG “2.2 mm” is the second range PR2 is determined as the height position HGP in the first height position candidate HGPP1.

<Effect of the embodiment>
In the present embodiment, in the height position HGP determination process C3, the process CB3 calculates the first thickness difference TDF1 by subtracting the minimum thickness MNT from the maximum thickness MXT. The process CB4 determines whether the first thickness difference TDF1 is "0.4 mm" or less, and proceeds to the process CB5 when it is "0.4 mm" or less, and processes when it is not "0.4 mm" or less Go to CB6. The processing CB5 determines the lowest position among the positions from the first position P1 to the sixth position P6 where the minimum thickness MNT and the maximum thickness MXT are the first range PR1 as the height position HGP. The processing CB6 determines the height position HGP based on the thickness number TN. Therefore, the first position where the maximum thickness MXT and the minimum thickness MNT fall within the first range when the first thickness difference TDF1 is "0.4 mm" or less, which is a case where the thickness variation of the sheet member SM is small. The lowest position among the positions from P1 to the sixth position P6 is determined as the height position HGP, and the first thickness difference TDF1 which is a case where the thickness variation of the sheet member SM is large is not "0.4 mm or less" In this case, since the height position HGP is determined based on the thickness number TN, an edge image of the sheet member SM can be generated even when reading the sheet member SM having asperities.

  In the process CB6, the process CC1 counts the number of types of each thickness from each thickness stored in the RAM 13 as the number TN of thicknesses. The process CC2 determines whether the thickness number TN is "3" or more, proceeds to process CC4 when it is "3" or more, and proceeds to process CC3 when it is less than "3". The processing CC3 determines the lowest position among the positions from the first position P1 to the sixth position P6 where the maximum thickness MXT is the first range PR1 as the height position HGP. The processing CC4 determines the height position HGP based on the second thickness difference TDF2. Therefore, when the thickness number TN is less than "3", there are only two types of thickness, and therefore, the positions from the first position P1 to the sixth position P6 where the maximum thickness MXT is the first range PR1. By determining the lowest position as the height position HGP, it is possible to reliably detect an edge image of a convex portion of the maximum thickness MXT.

  In the process CC4, the process CD1 calculates a second thickness difference TDF2 by subtracting the second smallest thickness among the thicknesses stored in the RAM 13 from the maximum thickness MXT. The treatment CD 2 determines whether the second thickness difference TDF 2 is "0.4 mm" or less, and proceeds to the treatment CD 3 when it is "0.4 mm" or less, and is processed when it is not "0.4 mm" or less Go to CD4. Among the thicknesses stored in the RAM 13, the treatment CD 3 is the lowest position among the first position P1 to the sixth position P6 where the thickness excluding the minimum thickness MNT is all within the first range PR1. Determined as HGP. The processing CD 4 determines the height position HGP based on the integrated distance AL in the transport direction TD. Therefore, when there are a plurality of convex portions attached to the sheet member SM, which is a case where the second thickness difference TDF2 is “0.4 mm or less”, and a difference in thickness of the plurality of convex portions is small, a plurality of convex portions There are a plurality of convex portions attached to the sheet member SM which can detect all the edge images of the part and the second thickness difference TDF2 is not "0.4 mm" or less, and the thickness of the plurality of convex portions If the difference is large, it is possible to detect the edge image of the convex portion having the largest detection number among the plurality of convex portions.

  In the process CD4, the process CE1 extracts the thickness associated with the largest detected number among the thicknesses obtained by removing the minimum thickness MNT from the thicknesses stored in the RAM 13 as the first thickness TN1. The processing CE2 extracts the positions from the first position P1 to the sixth position P6 where the first thickness TN1 is the first range PR1 as the first height position candidate HGPP1. The processing CE4 extracts the thickness excluding the minimum thickness MNT and the first thickness TN1 among the thicknesses stored in the RAM 13 as a thickness group TNG. The processing CE5 determines whether or not there is a position from the first position P1 to the sixth position P6 where the thickness group TNG is all the second range PR2 among the first height position candidate HGPP1. The second range PR2 The process proceeds to step CE6 when there is a position where is and the process proceeds to step CE7 when there is no position that becomes the second range PR2. The processing CE6 determines the lowest position among the first height position candidate HGPP1 as the height position HGP among the positions from the first position P1 to the sixth position P6 where the thickness group TNG is all the second range PR2 Do. Therefore, when the first height position candidate HGPP1 whose convex portion of the first thickness TN1 is the first range PR1 among the plurality of convex portions is the position where the convex portion of the thickness group TNG is the second range PR2 By determining the lowest height position among the first height position candidates HGPP1 as the height position HGP, it is possible to detect edge images of a plurality of convex portions attached to the sheet member SM.

  The processing CE3 extracts the position from the first position P1 to the sixth position P6 where the first thickness TN1 is the second range PR2 as a second height position candidate HGPP2. The processing CE7 determines whether or not there is a position from the first position P1 to the sixth position P6 where the thickness group TNG is all the second range PR2 among the second height position candidates HGPP2, and the thickness group TNG The process proceeds to processing CE8 when there is a position that is all within the second range PR2, and proceeds to processing CE9 when there is no position where all the thickness groups TNG are within the second range PR2. The processing CE8 determines the lowest position among the second height position candidate HGPP2 as the height position HGP among the positions from the first position P1 to the sixth position P6 where all the thickness groups TNG are in the second range PR2 Do. Therefore, when there is a position where the second height position candidate HGPP2 in which the convex portion of the first thickness TN1 is the second range among the plurality of convex portions and the convex portion of the thickness group TNG is the second range PR2 By determining the lowest position of the height positions as the height position HGP, it is possible to detect edge images of a plurality of convex portions attached to the sheet member SM.

  The processing CE9 adds all detection numbers associated with all the thicknesses included in the second range PR2 in the thickness group TNG at each height position of the second height position candidate HGPP2 and adds the integration distance AL. calculate. The processing CE10 determines, as the height position HGP, the height position corresponding to the largest integration distance AL among the integration distances AL calculated for each height position of the second height position candidates HGPP2. . Therefore, among the plurality of convex portions, among the second height position candidate HGPP2 in which the convex portion of the first thickness TN1 is the second range PR2, the convex portion of the thickness group TNG included in the second range PR2 is associated By determining the largest height position of the integrated distance AL obtained by adding the detected number as the height position HGP, it is possible to detect edge images of a plurality of convex portions attached to the sheet member SM.

[Correspondence between embodiment and invention]
The image reading device 1 and the mat 40 are an example of the image reading device and the mat of the present invention. The reading unit 17, the device control unit 22, the AFE 28, and the image processing unit 29 are an example of the reading unit of the present invention. The drive circuit 18, the conveyance motor MT2, and the conveyance rollers 52 and 53 are examples of the moving unit of the present invention. The height detection roller 51 and the height detection sensor 23 are an example of a detection unit of the present invention. The height adjustment mechanism MM, the drive circuit 18, and the height adjustment motor MT1 are an example of the height adjustment unit of the present invention. The CPU 11 is an example of a control unit of the present invention. The first range PR1 is an example of the first range of the present invention. The second range PR2 is an example of a second range of the present invention. The number of detections is an example of the number of positions of the present invention.

  Process C2 is an example of the detection process of the present invention. Process CB3 is an example of the first difference calculation process of the present invention. The process CB4 is an example of the first thickness difference determination process of the present invention. Process CB5 is an example of the first change process of the present invention. Process CB6 is an example of the second change process of the present invention. Process C4 is an example of the reading process of the present invention. The process CC1 is an example of the thickness number calculation process of the present invention. The process CC2 is an example of the thickness number determination process of the present invention. The process CC3 is an example of the third change process of the present invention. The process CC4 is an example of a fourth change process of the present invention. The process CB1 is an example of the position number calculation process of the present invention. Process CD1 is an example of the 2nd difference calculation process of this invention. Processing CD2 is an example of the 2nd thickness difference judging processing of the present invention. The processing CD 3 is an example of the fifth change processing of the present invention. The process CD 4 is an example of the sixth change process of the present invention. The treatment CE1 is an example of the longest thickness determination process of the present invention. Process CE5 is an example of the seventh change process of the present invention. Process CE6 is an example of the seventh change process of the present invention. The processing CE7 to the processing CE10 are an example of the eighth change processing of the present invention. The processing CE7 is an example of the second thickness determination processing of the present invention. Process CE8 is an example of the ninth change process of the present invention. The processing CE9 and the processing CE10 are examples of the tenth modification processing of the present invention. Process CE9 is an example of the total position number calculation process of the present invention. Process CE10 is an example of the eleventh change process of the present invention.

[Modification]
The present invention is not limited to the present embodiment, and various modifications can be made without departing from the scope of the present invention. An example of the modification is described below.

  (1) The image reading apparatus 1 of the present embodiment may be applied to a multifunction peripheral provided with a printer unit.

  (2) Although the thickness of the sheet member SM is detected using the height detection roller 51 and the height detection sensor 23, it may be detected by a different method. The thickness of the sheet member SM may be detected using a sensor such as a displacement sensor or a length measurement sensor.

  (3) In the present embodiment, the first range PR1 is a range in which the reading unit 17 has an MTF of 30% or more of the resolution of 300 DPI, and the second range PR2 is the resolution of 150 DPI in the reading unit 17 Although the range is described as having a MTF of 30% or more, it may be a different range. For example, the first range PR1 is a range in which the reading unit 17 has an MTF of 30% or more with respect to the resolution of 600 DPI, and the second range PR2 is an MTF of 30% or more with respect to the resolution of 300 DPI. It may be a range having

  (4) In the present embodiment, the distance in the height direction HD of each position from the first position P1 to the sixth position P6 is "0.4 mm", but may be different distances. For example, if the distance in the height direction HD of each position is "0.2 mm", "0.4 mm", which is the determination reference of the processing CB4 and the processing CD2, becomes large, and the height direction HD of each position If the distance of is “0.6 mm”, “0.4 mm”, which is the determination criterion of the process CB4 and the process CD2, becomes smaller. Moreover, although the focus range of the reading part 17 was "0.8 mm", it may be a different distance. For example, if the focus range is “1.0 mm”, “0.4 mm”, which is the determination criterion of the process CB4 and the process CD2, becomes large, and if the focus range is “0.6 mm”, the process CB4 and "0.4 mm" which is a criterion of processing CD2 becomes small.

DESCRIPTION OF SYMBOLS 1 ... Image reader, 11 ... CPU, 12 ... ROM, 13 ... RAM, 14 ... Flash PROM, 15 ... Operation part, 16 ... Display part, 17 ... Reading part, 18 ... Drive circuit, 21 ... Mat sensor, 22 ... Device control unit 23 Height detection sensor 24 Bus 28 AFE 29 Image processing unit 31 Light source 32 Light receiving unit 33 Rod lens 34 Platen glass 40 Mat 51 Height detection roller, 52, 53 ... conveyance roller, 90 ... cutting part, MB ... main body, MM ... height adjustment mechanism, MT 1 ... height adjustment motor, MT 2 ... conveyance motor, SM ... sheet member, BP ... reference part, HDR: thickness detection area, PR1: first range, PR2: second range

Claims (6)

A reading unit that generates an edge image by reading a sheet member;
A mat on which the reference position in the height direction is determined and on which the sheet member is placed;
A moving unit that moves the mat to a position facing the reading unit in a conveyance direction orthogonal to the height direction;
A detection unit for detecting a sheet thickness which is a thickness of a sheet member placed on the mat in a height direction, wherein the sheet thickness is a distance from the reference position to an upper end position of the sheet member in the height direction A detection unit,
A height adjustment unit that changes the height position of the reading unit in the height direction in multiple steps in the height direction with respect to the reference position;
And a control unit,
The height adjustment unit may have a predetermined position of the reading unit in the height direction with respect to the reference position in order to change the height position of the reading unit by one of each of the multiple steps. 1 distance change,
A first range read by the reading unit with a resolution equal to or greater than a first predetermined value is a range of distance in the height direction with respect to the reference position, and a plurality of first ranges are determined corresponding to the multistage height positions, The focus range obtained by subtracting the lower limit value of the first range from the upper limit value of the one range is defined as the same,
The control unit
Detection processing for causing the detection unit to detect a plurality of sheet thicknesses of sheet members placed on the mat at a plurality of detection positions while moving the mat along the transport direction;
A first difference calculation process for calculating a first thickness difference obtained by subtracting a first minimum thickness which is the thinnest thickness of the plurality of sheet thicknesses from a maximum thickness which is the thickest thickness of the plurality of sheet thicknesses;
A first thickness difference determination process of determining whether the first thickness difference is equal to or less than a second distance, wherein the second distance is a distance obtained by subtracting the first distance from the focus range. Thickness difference judgment processing,
When the first thickness difference is equal to or less than the second distance, the height position of the reading unit corresponding to the first range in which the plurality of sheet thicknesses are all included in the plurality of first ranges A first determination process of determining the height position of the reading unit at the lowest height position;
When the first thickness difference is larger than the second distance, the height position of the reading unit is determined at the height position determined based on the minimum removal thickness obtained by removing the first minimum thickness from the plurality of sheet thicknesses. A second determination process to determine
A sheet member on which the height adjustment unit changes the height position of the reading unit at the height position determined in the first determination process or the second determination process, and the reading unit is placed on the mat And an image reading apparatus for performing an image reading process for causing the image reader to generate an edge image by reading the image data. The second determination process is
Thickness number calculation processing for calculating the number of thicknesses, which is the number of types of sheet thickness of sheet members placed on the mat, from the plurality of sheet thicknesses;
Thickness number determination processing to determine whether the thickness number is 3 or more;
When the thickness number is less than 3, at the lowest height position among the height positions of the reading unit corresponding to the first range including the maximum thickness among the multiple first ranges, A third determination process of determining the height position of the reading unit;
When the thickness number is 3 or more, the reading is performed at a height position determined based on a second thickness difference obtained by subtracting a second minimum thickness which is the thinnest one of the minimum removed thicknesses from the maximum thickness. The image reading apparatus according to claim 1, further comprising a fourth determination process of determining a height position of the unit. The control unit
A position number calculation process is performed to calculate the number of positions which is the number of detection positions at which each sheet thickness is detected for each sheet thickness among the plurality of sheet thicknesses,
The fourth determination process is
A second difference calculation process of calculating a second thickness difference obtained by subtracting the second minimum thickness from the maximum thickness;
A second thickness difference determination process of determining whether the second thickness difference is equal to or less than the second distance;
When the second thickness difference is equal to or less than the second distance, the most of the height positions of the reading unit corresponding to the first range in which the minimum removal thickness is all included in the plurality of first ranges A fifth determination process of determining the height position of the reading unit at a low height position;
When the second thickness difference is greater than the second distance, the height of the reading unit is determined at the height position determined based on the longest thickness, which is the calculated sheet thickness, of the largest number of positions among the minimum removal thicknesses. The image reading apparatus according to claim 2, further comprising: a sixth determination process of determining the height position. A second range in which the reading unit reads with a resolving power equal to or higher than a second predetermined value lower than the first predetermined value is a range of distance in the height direction with respect to the reference position. It is a range that includes one range, and a number is determined corresponding to each of the multistage height positions,
The sixth determination process is
A longest thickness determination process for determining the longest thickness;
The first longest height position, which is the height position of the reading unit corresponding to the first range including the longest thickness among the plurality of first ranges, is the minimum removal among the plurality of second ranges. A first thickness determination process of determining whether or not the height position of the reading unit corresponds to a second range in which the longest removed thickness excluding the longest thickness from the thickness is all included;
When the first longest height position is a height position of the reading unit corresponding to a second range in which the longest removal thickness is all included, the longest removal thickness is within the first longest height position. A seventh determination process of determining the height position of the reading unit at the lowest height position among the height positions of the reading unit corresponding to the second range which is all included;
The longest thickness is included in the plurality of second ranges when the first longest height position is not the height position of the reading unit corresponding to the second range in which the longest removal thickness is all included. An eighth determination process of determining the height position of the reading unit at a height position determined based on a second longest height position which is a height position of the reading unit corresponding to two ranges; The image reading apparatus according to claim 3, characterized in that The eighth determination process is
A second thickness determining whether or not the second longest height position is a height position of the reading unit corresponding to a second range in which all the longest removal thicknesses are included among the plurality of second ranges Judgment processing,
When the second longest height position is a height position of the reading unit corresponding to a second range in which the longest removal thickness is all included, the longest removal thickness is the second longest height position. Ninth determination processing of determining the height position of the reading unit at the lowest height position among the height positions of the reading unit corresponding to the second range which is all included;
When the second longest height position is not the height position of the reading unit corresponding to the second range in which the longest removal thickness is all included, the reading unit of each of the second longest height positions A height determination step of determining the height position of the reading unit at a height position determined based on a total position number determined by adding the number of positions corresponding to all sheet thicknesses included in the second range at the height position; The image reading apparatus according to claim 4, comprising: The tenth determination process is
The total number of positions for calculating the total number of positions by adding the number of positions corresponding to all sheet thicknesses included in the second range with respect to the height position of the respective reading units among the second longest height position Calculation processing,
An eleventh determination process of determining the height position of the reading unit at the height position of the reading unit at which the largest total number of positions among the second longest height positions is calculated; The image reading apparatus according to claim 5.