JP2018063120A - Adjustment method of watermark position inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for adjusting the setting of the resolution of a line camera and the angle, or the like, of a paper pressing roller and the line camera exactly and easily in a watermark inspection device for measuring a watermark position with good precision.SOLUTION: The method for adjusting a watermark inspection device enables adjusting the setting of the optimal resolution of a line camera in a direction of conveyance of a sheet paper 2 and the angle, or the like, of a paper pressing roller and the line camera exactly and easily in a watermark inspection device by comparing an image of the sheet paper taken when the sheet paper is at rest with an image when the sheet paper is being conveyed.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for accurately and easily adjusting a resolution of a line camera, an angle of a paper presser roller, a line camera, and the like in a penetration inspection apparatus for accurately measuring a penetration position.

  With the recent development of digital devices such as scanners and color copiers, it has become possible to easily produce elaborate counterfeit products such as banknotes and passports. One of the anti-counterfeiting measures is a precious printed material in which paper is creased so that the pattern cannot be visually recognized under reflected light but can be recognized only under transmitted light. For this reason, when producing a precious printed matter that requires printing and precise printing, the position at which the printing is performed is extremely important when the paper is manufactured.

  Manufacture of sheets that have been squeezed is made by squeezing the strip-shaped paper into a fixed position with a paper machine before printing, and then winding the strip-shaped paper. In this case, the sheet is conveyed while being unrolled and cut into a predetermined size to produce a sheet. In the cutting machine, it is necessary to detect the crease in the belt-like paper being conveyed by an optical sensor, and to control the rotation speed of the cutter of the cutting machine with high accuracy based on this detection signal.

  However, in a paper machine, it is necessary to dry the paper in a predetermined position on the belt-like paper, and then dry the paper with the dryer section of the paper machine. The position of may change. In addition, the belt-like paper conveyed at high speed by the cutting machine may meander left and right or flutter up and down, resulting in inaccurate detected squeeze signal and cutting as a sheet with the squeezed position shifted. is there.

  Therefore, as a method for accurately inspecting the position of the insertion, the applicant of the present invention provides an area where no conveyor exists in the conveyor that conveys the sheet, and displays a transmission image of the sheet insertion. After taking an image and calculating the distance from the paper edge coordinate to the clearance coordinate, it is determined whether the calculated distance between the coordinates is within an allowable range, and a pass / fail determination of the position where the clearance is formed is performed. An application has been filed for a method for inspecting a squeeze position using a squeeze position inspecting device characterized by (see, for example, Patent Document 1).

JP 2012-247278 A

  However, although the invention of Patent Document 1 can measure the position where the clearance has been applied with stable and high accuracy without causing variations, there are the following problems when aiming at further technical improvement.

  Since the technique of Patent Document 1 needs to measure the insertion position with high accuracy, it is required to capture a transmission image without distortion. However, the sheet is skewed during conveyance of the sheet, or Depending on the mounting angle of the line camera, a distorted transmission image is captured.

  In the technique of Patent Document 1, when a transmission image having a distorted shape is formed, it becomes impossible to accurately inspect the penetration position. Therefore, it is investigated whether the resolution of the line camera of the penetration position inspection apparatus is appropriate. Even if the resolution of the line camera is appropriate, if the sheet transport direction is tilted, it is necessary to adjust the sheet press roller or line camera to correct the sheet transport direction tilt. is there.

  However, in the penetration inspection apparatus, the investigation of the resolution of the line camera in the sheet conveyance direction and the adjustment (pressing, angle, etc.) of the paper presser roller and the line camera are fine adjustments, and are skilled. However, it takes time and effort, and there is a problem that the inspection accuracy may be lowered due to a wrong adjustment.

  In order to solve the above-mentioned problems, the present invention provides an optimal and easy method for adjusting the optimal resolution of the line camera in the sheet conveying direction of the penetration inspection apparatus and the paper presser roller and the line camera. To do.

  The present invention provides a paper presser roller that conveys a sheet by pressing the sheet against a belt using an inspection accuracy adjustment device having at least a length measuring unit, and a line camera for imaging a gap formed on the sheet. In the method of adjusting and measuring the insertion position with high accuracy, (i) a step of measuring the insertion position or the sheet size by taking a transmission image or a reflection image of the sheet in advance by the length measurement unit; (Ii) a step of taking a transmission image or a reflection image of the same sheet as the sheet measured in step (i) with a line camera and measuring the insertion position or the size of the sheet; iii) Subtracting the position of the squeezing position or the sheet measured in step (ii) from the squeezing position or the size of the sheet measured in step (i) to obtain the difference in the squeezing position or the sheet With the difference in dimensions Calculating a test error that is a method of adjusting the plow insertion inspection device characterized by comprising a.

  (Iv) After performing step (iii), the present invention calculates the resolution of the line camera by dividing the cleaning position or the sheet size measured in step (i) by the number of pixels of the line camera, A method for adjusting a penetration inspection apparatus comprising a step of adjusting the resolution of a line camera.

  The present invention is a method for adjusting a penetration inspection apparatus, comprising the step of adjusting the pressing of a paper pressing roller with respect to a belt direction of a sheet after performing (v) step (iv).

  The present invention comprises (vi) a step of adjusting the mounting angle of the presser roller mounting shaft of the presser roller with respect to the sheet transport direction after performing step (v). This is an apparatus adjustment method.

  The present invention is a method for adjusting a penetration inspection apparatus, comprising the step of adjusting a mounting angle of a line camera with respect to a sheet conveyance direction after performing (vii) step (vi).

  The present invention compares the image captured with the sheet still and the image of the sheet being transported, so that the optimum line camera in the sheet transport direction of the penetration inspection apparatus It is possible to accurately and easily adjust the resolution setting, the paper pressing roller and the angle of the line camera.

Example of sheet Configuration diagram of inspection accuracy adjustment device Example of measuring section Length measuring unit placed in the clearance position inspection device Measurement result of penetration position Example diagram showing a sheet image by the length measuring section Side view of clearance position inspection device Plan view of clearance position inspection device (Description of line camera, paper presser roller mounting frame, etc. omitted) Sheet paper image Sheet paper image Sheet paper image Paper presser roller pressing adjustment section Layout of 4 paper presser rollers Paper presser roller press database (machine operation side) Paper presser roller press database (machine drive side) Paper presser roller mounting angle adjustment section Inclined view of shaft for mounting paper presser rollers Sheet paper image Sheet paper image Paper presser roller mounting angle database Line camera mounting angle adjuster (side view) Line camera mounting angle adjuster (plan view) Sheet paper image Sheet paper image Sheet paper image Line camera mounting angle database Operation flow chart of inspection accuracy adjustment device Resolution adjustment operation flow diagram by resolution adjustment unit Paper presser roller pressing adjustment operation flow chart by the paper presser roller pressing adjustment unit Paper presser roller mounting angle adjustment operation flow chart by the paper presser roller mounting angle adjustment unit Line camera mounting angle adjustment flow chart by the line camera mounting angle adjustment unit

  Embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments to be described below, and various other embodiments can be implemented within the scope of the technical idea described in the claims.

  FIG. 1 is an example of a sheet (2) to be inspected in the present embodiment. The shape of the sheet (2) is a rectangle in which all corners from A to D are at right angles. Further, the sheet (2) is provided with a gap (29) made up of characters a, b, c and d.

  FIG. 2 is a block diagram showing the inspection accuracy adjusting device (17) of the present invention for adjusting the penetration position inspection device (1). The inspection accuracy adjusting device (17) includes a control unit (18), a length measuring unit (19), a resolution adjusting unit (21), a paper presser roller press adjusting unit (22), a paper presser roller mounting angle adjusting unit (23), and It is comprised from a line camera attachment angle adjustment part (24). In the present embodiment, the inspection accuracy adjusting device (17) is formed off-line of the penetration position inspection device (1), but may be formed on-line of the penetration position inspection device (1).

(Measurement Department)
FIG. 3 is an example of the length measuring unit (19) of the inspection accuracy adjusting device (17) of the present embodiment. As shown in FIGS. 3 (a) and 3 (b), the length measuring section (19) has a placing means (25) for setting the sheet (2) and visible light on the sheet (2). Irradiating means (26) for irradiating, an imaging means (27) for capturing an optical image of the sheet (2), and a processing means (28) for processing the captured image. The length measuring unit (19) shown in FIG. 3A is an example for measuring the insertion position applied to the sheet (2) by the transmission image. As shown in FIG. 3 (a), the length measuring section (19) is provided with the irradiation means (26) from the lower part of the sheet (2) set on the transparent glass (52) as the placing means (25). ) Is irradiated with visible light from the area camera illumination (transmission (53)), and the sheet (2) is picked up by the area camera (54) as the imaging means (27) mounted on the sheet (2). ), And the transmission image is processed by the length measuring computer (55) as the processing means (28) to measure the position of the gap (29) applied in the sheet (2). To do.

  Further, the length measuring unit (19) shown in FIG. 3B is an example of measuring the size of the sheet on the sheet (2) by the reflected image. The length measuring unit (19) measures the dimension of the sheet (2) from the reflected image when the insertion position inspection device (1), which will be described later, can measure the dimension of the sheet (2). The squeeze position inspection error can be reduced from the dimensional inspection error that is the difference in the dimensional measurement values of the paper (2). Therefore, in the present embodiment, a method for reducing the insertion position inspection error from the dimension inspection error of the sheet (2) will be described.

(Reflection type)
As shown in FIG. 3 (b), the length measuring section (19) is arranged to irradiate the irradiation means (26) from the upper part of the sheet (2) set on the installation board (30) which is the placing means (25). ) Is irradiated with visible light from the area camera illumination (reflecting (31)), and the sheet (2) is captured by the area camera (54) which is the imaging means (27) attached to the upper part of the sheet (2). ), And the reflected image is processed by the length measuring computer (55) as the processing means (28) to detect the coordinates of the four corners of the sheets (2) A to D shown in FIG. Then measure. When the installation board (30) is used as the placing means (25), an electrostatic suction device (not shown) and an air suction device that prevent the sheet (2) from waving and rising during imaging. (Not shown). Further, the installation board (30) is coated with matte black so that each corner and each side of the white sheet (2) can be clearly imaged. It is possible to measure the coordinates of all the corners and the paper shapes such as the shape of each side and rhombus by image processing by the length measuring computer (55) which is (28).

  In addition, when the length measuring unit (19) is arranged off-line of the penetration position inspection device (1), the operator cleans the sheet (2) not measured by the length measuring unit (19). There is a risk of throwing it into the position inspection device (1). Therefore, as shown in FIG. 4, when the length measuring section (19) is arranged upstream of the upstream conveyor (3) of the pouring position inspection device (1), it is surely the same sheet (2). It is possible to measure the dimensional inspection error.

  As an example, when the measuring position of the sheet (2) shown in FIG. 1 is measured by the length measuring unit (19), the characters a, b, c and d are inserted as shown in FIG. ) Is measured for the position of the insertion from the reference point (D corner) of the sheet (2), and the insertion position of the letter a is the coordinate of the reference point (D corner). When (0,0) is taken as a coordinate, it is measured as coordinates (AXmm, AYmm).

  When the dimension of the sheet (2) is measured by the length measuring unit (19), as shown in FIG. 6, the captured sheet image (32) is obtained by the length measuring computer (28). , Each corner is detected, D corner is set as a reference point (0, 0), and the position coordinates of each corner of A corner (AXmm, AYmm), B corner (BXmm, BYmm), C corner (CXmm, CYmm) taking measurement. In the following description, the X coordinate of the A corner is AX, the Y coordinate of the A corner is AY, the X coordinate of the B corner is BX, the Y coordinate of the B corner is BY, the C corner X coordinate is CX, and the Y coordinate of the C corner is This will be described as CY. As an example, when the sheet (2) shown in FIG. 1 is a rectangle having an X direction of 600 mm and a Y direction of 400 mm, the D corner is set as the reference point (0, 0) and the A corner (0. 0, 400.0), B corner (600.0, 400.0), and C corner (600.0, 0.0).

  In this embodiment, the area camera (54) is used as the image pickup means (27) of the length measuring unit. However, if the reflected image or the transmitted image can be clearly captured and the paper size or the insertion position can be accurately measured. Well-known length measuring means using an optical image pickup means using a scanner type or a CCD camera, an image pickup means by laser interference, or the like can be used.

(Insertion position inspection device)
Next, the sheet (2) measured by the length measuring unit (19) is put into the feeder of the poking position inspection device (1) by the operator, and is sent by the line camera of the poking position inspection device (1). An image of the sheet (2) is taken. FIG. 7 shows an example of the squeeze position inspection apparatus (1), and a conveyor for capturing a transmission image of the sheet (2) in order to inspect the squeeze position applied to the sheet (2). A side view of a non-existing region is shown. FIG. 8 is a plan view thereof. In the following description, the machine width direction will be described as the X direction, the sheet conveyance direction as the Y direction, and the height direction as the Z direction.

  As shown in FIG. 7, the insertion position inspection device (1) includes a feeder (not shown) that conveys the sheet (2), a stacking unit (not shown) that stacks the sheets (2), and a gap therebetween. In order to prevent flapping of the upstream conveyor (3) and downstream conveyor (4) that convey the sheet (2) and the sheet (2) being conveyed, the sheet (2) is sandwiched from above and below A presser plate (5), a paper presser roller (6) that stably conveys the sheet (2), an illumination (7) and a line camera (8) for capturing a transmission image of the sheet (2), It comprises an inspection section (9) for performing image processing of light transmitted through the sheet (2) received by the line camera (8). An encoder (12) for controlling the imaging timing of the line camera (8) is attached to the axis of the roller (11) on the downstream side of the downstream conveyor (4).

  FIG. 9 is a sheet image (33) captured by the line camera (8) of the penetration position inspection device (1), and is a diagram in which the coordinates of each corner position are measured. As shown in FIG. 9, the captured sheet image (33) has a resolution of 0. 0 in the X and Y directions of the line camera (8). When xmm is set, the A corner (AXmm, AYmm) (AX / 0.x pixel, AY / 0.x pixel), the B corner (BXmm, BYmm) (BX / 0) with the D corner as a reference point .X pixel, BY / 0.x pixel), C corner is measured as (CXmm, CYmm) (CX / 0.x pixel, CY / 0.x pixel), and each corner coordinate is measured. For example, when the resolution of the line camera (8) in the X direction and the Y direction is set to 0.2 mm and the sheet (2) shown in FIG. Corner (0.0 mm, 400.2 mm) (0 pixel, 2001 pixel), B corner (599.8 mm, 400.4 mm) (2999 pixel, 2002 pixel), C corner (600.0 mm, 0.0 mm) (3000 Each corner coordinate is measured as (pixel, 0 pixel).

(Control part)
The control unit (18) includes a length measuring unit (19), a resolution adjusting unit (21), a paper presser roller press adjusting unit (22), a paper presser roller mounting angle adjusting unit (23), and a line camera mounting angle adjusting unit (24). ) Is controlled. Further, the control unit (18) is preset with calculation means for calculating a dimension inspection error which is a difference between the dimension measured by the length measuring unit (19) and the dimension measured by the penetration position inspection device (1). Consists of a recording means for registering a tolerance value of the dimension inspection error, a comparison means for comparing the calculated dimension inspection error with a preset tolerance value of the dimension inspection error, and a determination means for judging whether or not the dimension inspection error is within an allowable range. When the dimensional inspection error is an allowable value by the determination means, it is determined that the inspection function of the cleaning position inspection device (1) is normal, and the control unit (18) can operate the cleaning position inspection device (1). And a signal indicating that the penetration position inspection device (1) is operable on the display unit (20). On the other hand, if the calculated dimension inspection error is greater than or equal to the allowable value, the inspection function of the penetration position inspection apparatus (1) is determined to be abnormal, and the control section (18) cannot operate the penetration position inspection apparatus (1). While transmitting a certain signal, it displays on the display unit (20) that the operation is impossible.

  The dimensional inspection error in this specification is an inspection error in the dimensional inspection of the penetration position inspection device (1), and the dimensional measurement value of the length measuring unit (19) from the dimensional measurement value of the penetration position inspection device (1). The value obtained by subtracting For example, the coordinate BX of the sheet (2) measured by the length measuring unit (19) is 600.0 mm, and the BX measured by passing the sheet (2) through the pouring position inspection device (1) is measured. In the case of 599.8 mm, -0.2 mm obtained by subtracting the measured value BX600.0 mm of the length measuring unit (19) from the measured value BX599.8 mm of the penetration position inspection device (1) is the BX dimensional inspection error. .

  In order for the calculated dimension inspection error to accurately represent the penetration position inspection error of the penetration position inspection apparatus (1), the measurement error of the length measuring unit (19) is measured by the penetration position inspection apparatus (1). It is smaller than the error, and should be about 10%. If it exceeds 10%, it will not be possible to accurately represent the pouring position inspection error of the pouring position inspection device (1), and in the next printing process, it will be difficult to align printing and precise printing. It becomes. For example, when the dimensional inspection error of the length measuring unit (19) is ± 0.5 mm and the dimensional inspection maximum error of the penetration position inspection device (1) is ± 0.4 mm, the calculated dimensional inspection error is the penetration The value is larger than the true maximum error of the position inspection apparatus (1), and an accurate dimensional inspection error of the clearance position inspection apparatus (1) cannot be expressed. Therefore, when the maximum error in the paper size inspection of the penetration position inspection apparatus (1) is ± 0.4 mm, the measurement error of the penetration position of the length measuring unit (19) needs to be about ± 0.05 mm.

  In addition, the dimensional inspection error is calculated when a single sheet (2) measured by the length measuring unit (19) is passed through the insertion position inspection device (1) once and calculated. There is a possibility that the dimensional inspection error may become inaccurate due to the conveyance error of (2). For this reason, a single sheet (2) measured by the length measuring unit (19) is repeatedly passed through the poking position inspection device (1) about 10 times, and about 10 obtained dimensional inspection errors. The maximum value may be a dimensional inspection error of the penetration position inspection device (1). Further, about 10 sheets (2) measured by the length measuring section (19) are passed through the cleaning position inspection device (1), and the maximum value of the dimensional inspection error of each sheet (2) is determined. It may be a dimensional inspection error of the insertion position inspection device (1).

  The permissible value of the inspection of the penetration position inspection device (1) registered in advance in the recording means of the control unit (18) is a target value when the inspection accuracy adjusting device (17) performs various adjustments. Therefore, since the allowable values of AX, BX, CX, AY, and BY are changed when each part is adjusted, the dimensional inspection error of the penetration position inspection device (1) can be effectively reduced.

(Resolution adjustment unit)
The resolution adjusting unit (21) measures the measured value of the sheet (2) dimension measured by the length measuring unit (19), and the sheet image (counted by the penetration position inspection device (1)) and counted. 33) receiving the number of pixels in the X direction and the Y direction, and then measuring the measured value of the dimension of the sheet (2) measured by the length measuring unit (19) in the X direction by the penetration position inspection device (1) and By dividing by the number of pixels in the Y direction, the resolution of the line camera (8) in the X direction and the Y direction is calculated. After the calculation of the resolution of the line camera (8), it is transferred to the inspection unit (9) of the penetration position inspection device (1) and set as the resolution of the line camera (8).

  After setting the resolution of the line camera (8) of the penetration position inspection device (1), the sheet (2) measured by the length measuring unit (19) is again passed through the penetration position inspection device (1). When the dimensional inspection error from the paper sheet AX to AY is calculated and the calculated dimensional inspection error is outside the range of the allowable value determined in advance by the control unit (18), the paper pressing roller pressing adjustment unit ( 22), the pressing of the paper pressing roller (6) of the insertion position inspection device (1) is adjusted.

(Paper presser roller pressing adjustment section)
As shown in FIG. 7 or FIG. 8, the two paper pressing rollers (6) of the pouring position inspection device (1) are evenly attached from the center of the machine on the inlet side of the downstream conveyor (4). Therefore, the sheet (2) conveyed from the upstream conveyor (3) and passing through the imaging area of the line camera (8) can be conveyed straight.

  A paper presser roller (6) is attached to the upstream end of the arm (13), and a spring (16) is attached to the downstream end of the arm (13). The arm (13) rotates about the paper presser roller mounting shaft (14) as an axis, and the spring (16) held by the paper presser roller mounting frame (15) moves the paper presser roller (6) downstream. Press against the side conveyor (4). Therefore, the paper pressing roller (6) can convey the sheet (2) in synchronization with the entire belt (10) of the downstream conveyor (4).

  All the paper presser rollers (6) are fastened perpendicularly to the Z direction by the paper presser roller mounting shaft (14) and the arm (13). Therefore, the angle of the paper presser roller mounting shaft (14) in the X direction is set. By changing, all the paper presser rollers (6) can be at the same angle. The diameter and width of the paper pressing roller (6) are appropriately set depending on the diameter, material, speed, etc. of the conveyor roller. Further, since the surface of the paper pressing roller (6) needs to securely grip the sheet (2) when transporting the paper, natural rubber, urethane rubber, silicon rubber, which is an elastic material having a large friction coefficient. Fluorine rubber or the like is wound around. From the viewpoint of durability, urethane rubber is preferable.

  7 and 8, when the gripping force of the two paper pressing rollers (6) is equal, the sheet (2) passing through the line camera imaging region is straight. Therefore, the sheet image (33) captured by the line camera (8) has a shape similar to that of the sheet (2). However, when the gripping force of the two paper pressing rollers (6) is not uniform, the sheet (2) passing through the line camera imaging area is conveyed to be inclined to the machine operation side or the machine drive side. The sheet image (33) captured by the line camera (8) is distorted.

  For example, when the grip force of the paper presser roller (6) on the machine driving side is stronger than the grip force of the paper presser roller (6) on the machine operation side, the sheet presser roller (6) has a strong grip. ), The image (33) of the sheet (2) taken by the line camera (8) is longer in the machine operation side in the Y direction and paper in the X direction, as shown in FIG. It has a rhombus shape that leans toward the machine drive side toward the bottom. Further, when the gripping force of the paper pressing roller (6) on the machine operation side is stronger than the gripping force of the paper pressing roller (6) on the machine driving side, the sheet pressing roller (6) has a strong grip. ), The sheet image (33) taken by the line camera (8) is long in the Y direction on the machine drive side and in the X direction toward the paper bottom as shown in FIG. It has a rhombus shape inclined to the operation side.

  Thus, the grip force of the paper pressing roller (6) greatly affects the behavior of the sheet (2) passing through the line camera imaging region. The force with which the paper pressing roller (6) grips the sheet (2) is most affected by the pressing of the paper pressing roller (6). Therefore, the paper presser roller press adjusting unit (22) can adjust the behavior of the sheet (2) passing through the line camera imaging region by adjusting the press of the paper presser roller (6).

  As shown in FIG. 12, the paper presser roller pressing adjustment unit (22) includes a motor (34) that adjusts the length of the spring (16), a load sensor (35) that measures the press of the paper presser roller (6), and press control. It consists of a device (36) and the like. The pressing of the paper pressing roller (6) is performed by changing the length of the spring (15) attached between the arm (13) of the paper pressing roller (6) and the paper pressing roller mounting frame (15) by the motor (34). It can be changed.

  The press control device (36) stores the press of the paper presser roller (6) and the press database, the press comparing means for comparing the press of the paper presser roller (6), and the press of the paper presser roller (6). It consists of pressing adjustment means to adjust. The pressure comparison means subtracts the BY dimension inspection error from the AY dimension inspection error transferred from the control unit (18), and when the value is “+”, the gripping force of the paper pressing roller (6) on the machine operation side is It can be seen that it is weaker than the machine drive side. Therefore, the press control device (36) performs adjustment to increase the press of the paper presser roller (6) on the machine operation side by the press adjusting means. On the other hand, when the value obtained by subtracting the BY dimension inspection error from the AY dimension inspection error is “−”, it is understood that the grip force of the paper pressing roller (6) on the machine drive side is weaker than that on the machine operation side. The device (36) performs adjustment to increase the pressing of the paper pressing roller (6) on the machine driving side by the pressing adjusting means.

  For example, the gripping force of the paper presser roller (6) is reduced because paper dust or dust has adhered to the surface of the paper presser roller (6), and the dimensional inspection error is outside the range of allowable values set in advance in the control unit (18). First, the dimension measurement by the length measuring unit (19) is performed, and the pressing control device (36) calculates AY-BY by the pressing comparing means, and the value of AY-BY becomes substantially zero. The pressing of the paper pressing roller (6) is adjusted by the pressing adjusting means.

  Appropriate pressing of the paper presser rollers (6) at which the value of AY-BY is substantially zero includes the number of paper presser rollers (6), the mounting position of the paper presser rollers (6) in the X direction, the paper presser rollers (6 ) Diameter and width and the rating of the spring (16) of the paper presser roller (6). Therefore, the press control device (36) is provided with an appropriate press of the paper presser roller (6) in advance. Must be registered in the database.

  In addition, when the pressing force of the paper pressing roller (6) is large, the synchronization between the sheet (2) and the belt is increased, and it becomes possible to reduce the dimensional inspection error. ) Is linearly increased in the X direction. For example, as shown in FIG. 13, if four paper presser rollers (6) are arranged at equal intervals, the dimensional inspection error can be reduced compared to the case of two paper presser rollers (6).

  14 and 15 are pressing databases relating to the four paper pressing rollers shown in FIG. As shown in FIG. 14, the pressure on the machine operation side is a force suitable for AY-BY on the straight line indicated by the straight line (n−1). For example, when the press of the paper presser roller (6) is set to 21 N and the value of AY-BY is -0.15 mm, refer to the press database related to the presser roller (6) on the machine operation side in FIG. The pressing of the two paper pressing rollers (6) on the machine operation side is changed from 21N to 18N. Further, without changing the pressing of the paper pressing roller (6) on the machine operation side, the pressing of the two paper pressing rollers (6) on the machine driving side is referred to with reference to the paper pressing roller pressing database shown in FIG. Adjusting the pressure on the machine drive side to a force suitable for AY-BY, which is on the straight line indicated by the straight line (n-2), gives substantially the same result.

  In order to improve the synchronism between the sheet (2) and the belt, which side of the paper pressing roller (6) on the machine operation side or the machine driving side is adjusted is adjusted. Adjustment by the spring (16) that increases the pressing of the paper pressing roller (6) is effective. However, since the pressure at which the paper pressing roller (6) is stabilized is determined in advance by the rating of the spring (16), the pressing adjustment needs to be adjusted so as not to exceed the rating of the spring (16).

  As described above, the dimensional inspection error can be reduced by performing automatic adjustment by the paper presser roller pressing adjustment unit (22). However, when there are no devices such as a load sensor and a motor (34), the paper presser roller press adjusting unit (22) displays the adjustment content of the paper presser roller (6) on the display unit (20), and the operator Adjust the pressure of the paper presser roller (6) according to the displayed instructions.

  After automatic adjustment by the paper presser roller pressing adjustment unit (22), the resolution setting of the insertion position inspection device (1) is performed and the sheet (2) measured by the length measurement unit (19) is again inserted. The paper is passed through the position inspection device (1) to calculate a dimensional inspection error. As a result of the calculation, when the dimensional inspection error is outside the range of the allowable value determined in advance in the control unit (18), first, the pressing of all the paper pressing rollers (6) is adjusted to the reference pressing with the same force, Next, the attachment angle of the paper presser roller (6) is adjusted by the paper presser roller attachment angle adjusting unit (22).

(Paper presser roller mounting angle adjustment section)
As shown in FIG. 16, the paper presser roller mounting angle adjusting section (23) shown in FIG. 2 includes a machine operation side bearing section (37), a machine drive side bearing section (38), a motor (39), and a shaft angle control device. (40). A machine operation side bearing (37) and a machine drive side bearing (38) are attached to both ends of the paper presser roller mounting shaft (14). The machine operation side bearing (37) and the machine drive side bearing (38) are slidable in the Y direction by the rotation of the motor (39). Further, the shaft angle control device (40) calculates a slide amount and storage means for registering a paper presser roller mounting angle database which is a slide amount of the machine operation side bearing portion (37) and the machine drive side bearing portion (38). And a slide amount adjusting means for adjusting the slide amount.

  For example, as shown in FIG. 17, when the paper presser roller mounting shaft (14) is tilted counterclockwise with respect to the Y direction, the sheet (2) is transported while being tilted toward the machine drive side. Therefore, as shown in FIG. 18, the AY dimension inspection error is “+” compared to the BY dimension inspection error, and the BX and AX dimension inspection errors are “+” diamond shapes.

  The slide amount calculation means of the shaft angle control device (40) subtracts the BY dimension inspection error from the AY dimension inspection error transferred from the control unit (18), and the subtracted value AY−BY is “+”. Or “−”. When the AY-BY becomes “+”, the slide amount adjusting means rotates the paper presser roller mounting shaft (14) in the clockwise direction, so that the operation side bearing portion of the paper presser roller mounting shaft (14) is located upstream. Slide to the side. In order to rotate the paper presser roller mounting shaft (14) in the clockwise direction, the drive-side bearing portion of the paper presser roller mounting shaft (14) may be slid downstream.

  On the contrary, when the paper presser roller mounting shaft (14) is inclined clockwise with respect to the Y direction, the sheet (2) is conveyed while being inclined toward the machine operation side. Therefore, as shown in FIG. 19, the AY dimensional inspection error is “−” compared to the BY dimensional inspection error, and the AX and BX dimensional inspection errors are “−” diamond shapes. Therefore, in order to rotate the paper presser roller mounting shaft (14) in the counterclockwise direction, the operation side bearing portion of the paper presser roller mounting shaft (14) is slid to the downstream side. In order to rotate the paper presser roller mounting shaft (14) in the counterclockwise direction, it is also possible to slide the drive side bearing portion of the paper presser roller mounting shaft (14) to the upstream side.

  Thus, the rhombus shape of the image (33) of the sheet (2) can be corrected by the paper presser roller mounting angle adjusting unit (23) adjusting the angle of the paper presser roller mounting shaft.

  The slide amount of the machine operation side bearing part (37) and the machine drive side bearing part (38) that can correct the rhombus shape of the image (33) of the sheet (2) is the amount of slide of the sheet (2) to be inspected. It depends on the size, the shape of the paper presser roller (6), the pressing and arrangement, and the length of the paper presser roller mounting shaft (14). Therefore, the slide amount of the machine operation side bearing part (37) and the drive side bearing part (38) with respect to the value obtained by subtracting the BY dimension inspection error from the AY dimension inspection error is recorded in the recording means of the shaft angle control device (40). It is necessary to register in advance in the paper presser roller mounting angle database.

  FIG. 20 is a paper presser roller attachment angle database related to the four paper presser rollers shown in FIG. As shown in FIG. 20, the slide amount on the machine operation side is a straight line (m-1), the slide amount on the machine drive side is a straight line (m-2), and the machine operation side bearing portion (37) or machine for AY-BY This is the sliding amount of the drive side bearing portion (38).

  Further, when the operation-side bearing portion (37) and the drive-side bearing portion (38) are slid largely upstream, the paper pressing roller (6) enters the line camera imaging region, and the image of the sheet (2) ( 33) may not be accurately imaged. On the other hand, when the machine operation side bearing (37) and the machine drive side bearing (38) are slid largely downstream, the axis of the paper presser roller (6) and the axis of the downstream conveyor roller are aligned. The large deviation increases the rotational load of the entire belt (10) of the downstream conveyor (4), and the rotation of the entire belt (10) of the downstream conveyor (4) may become unstable. For this reason, in the shaft angle control device (40), a range in which the bearings on the machine operation side and the machine drive side can slide is registered in the storage means in advance, and within this range, the machine operation side bearing unit (37). And the mechanical drive side bearing part (38) is slid.

  As an example, in FIG. 20, when the image (33) of the sheet (2) in which the value obtained by subtracting the AY dimensional inspection error by the BY dimensional inspection error is +0.4 mm, Adjustment is performed by sliding the bearing portion (37) by -0.3 mm or sliding the mechanical drive side bearing portion (38) by +0.3 mm.

  As described above, the paper presser roller mounting angle adjustment unit (23) for adjusting the angle of the paper presser roller mounting shaft has been described. The same effect can be obtained even if the mounting shaft (14) is fixed and the paper pressing roller (6) attached to the paper pressing roller mounting shaft (14) is adjusted in position upstream or downstream in the conveying direction. This method may be used because it can be obtained. Alternatively, the paper pressing roller mounting shaft (14) may be a cantilever structure from the left and right frames, and the left and right frames may move upstream and downstream. About the adjustment method of the attachment angle of these paper pressing rollers (6), what is necessary is just to employ | adopt suitably the method suitable for the structure of the penetration position inspection apparatus (1).

  Thus, by performing automatic adjustment by the paper presser roller mounting angle adjustment section (23), the dimension inspection error can be reduced. However, if there is no device such as a motor (39) that automatically slides the machine operation side bearing (37) and the machine drive side bearing (38), the paper presser roller mounting angle adjustment unit (23) The adjustment content of the paper presser roller mounting shaft (14) is displayed in (20), and the operator adjusts the angle of the paper presser roller mounting shaft (14) according to the instruction.

  After adjusting the angle of the paper presser roller mounting shaft (14), the sheet (2) measured by the length measuring section (19) is again passed through the poking position inspection device (1) to perform dimension inspection. When the error is calculated, and the calculated dimension inspection error in the Y direction is outside the range of the allowable value determined in advance in the control unit (18), the paper presser roller mounting by the paper presser roller mounting angle adjusting unit (23) is performed again. The angle of the shaft (14) is adjusted. The second and subsequent adjustments by the angle adjusting portion of the paper presser roller mounting shaft (14) are slightly smaller than the angle adjusted at the first time in order to prevent the angle adjustment of the paper presser roller mounting shaft from being over-controlled. To do.

  As a result of automatic adjustment by the paper presser roller mounting angle adjustment unit (23), the dimensional inspection error in the Y direction falls within the allowable range predetermined in the control unit (18), and the dimensional inspection error in the X direction becomes the control unit (18). Then, the angle adjustment of the line camera (8) of the penetration position inspection device (1) is performed by the line camera mounting angle adjustment unit (24).

(Line camera mounting angle adjuster)
The line camera attachment angle adjustment unit (24) shown in FIG. 2 is a part for adjusting the angle of the line camera (8). As shown in FIGS. 21 and 22, the bracket (41), the line camera rotation screw ( 42) and a line camera angle adjusting device (43). The line camera (8) is attached through the bracket (41), and in the line camera (8), a light receiving element (45) that converts the light collected by the lens (44) into an electric signal. ) Is stored. The line camera angle adjustment device (43) includes a storage means for registering the line camera attachment angle and the line camera attachment angle database, an attachment angle calculation means for calculating the attachment angle, and an attachment angle adjustment means for adjusting the attachment angle. Become.

  The bracket (41) can be smoothly rotated by the bearing (48) by the rotation shaft (47) incorporated in the frame (46) of the penetration position inspection device (1). Also, a knob (49) that contacts the tip of the line camera rotation screw (42) is attached to the machine operation side surface of the bracket (41), and the frame (46) is attached to the machine drive side surface. A fixed spring (50) is attached.

  The line camera rotation screw (42) is rotated by the motor (51) controlled by the line camera angle adjusting device (43), and the bracket (41) is always rotated clockwise (T1) by the spring (50). Force to act. Because of this structure, the line camera angle adjustment device (43) can accurately adjust the angle of the light receiving element (45) of the line camera (8).

  When the light receiving element (45) of the line camera (8) is perpendicular to the Y direction (X direction and horizontal), as shown in FIG. 23, an image (33) of the sheet (2) captured by the line camera (8). The shape of is similar to the shape of the paper. However, when the line camera light receiving element is tilted rather than perpendicular to the Y direction, the shape of the image (33) of the sheet (2) is a rhombus shape different from the shape of the sheet (2).

  For example, as shown in FIG. 24, when the line camera light receiving element is tilted in the clockwise direction (T1), the image (33) of the imaged sheet (2) has a rhombus shape distorted on the machine drive side. On the contrary, as shown in FIG. 25, when the line camera light receiving element is tilted in the counterclockwise rotation direction (T2), the image (33) of the captured sheet (2) is distorted to the machine operation side. It becomes a shape.

  The dimension inspection errors of AX and BX in FIG. 24 are “+” because the A corner and the B corner are inclined toward the machine drive side in the “+” direction, and the dimension inspection errors of AX and BX shown in FIG. Since the A corner and the B corner are tilted toward the machine operation side in the “−” direction, it becomes “−”, and the line camera mounting angle adjustment unit (24) measures the dimensions of AX and BX transferred from the control unit (18). When the inspection error is “+”, the shape of the image (33) of the sheet (2) can be corrected by rotating the line camera (8) counterclockwise. Further, when the dimension inspection error of AX and BX transferred from the control unit (18) is “−”, the image (33) of the sheet (2) is rotated by rotating the line camera (8) in the clockwise direction. The shape of can be corrected.

  The appropriate rotation angle of the line camera (8) that can correct the rhombus shape of the image (33) of the sheet (2) is the imaging condition of the line camera (8), the X direction of the sheet (2). The length of the bracket, the size of the bracket (41), and the like. Therefore, it is necessary to investigate in advance the relationship between the AX or BX dimensional inspection error and the appropriate line camera mounting angle and register it in the line camera mounting angle database in the line camera angle adjusting device (43). is there.

  FIG. 26 is a line camera attachment angle database regarding the four paper pressing rollers shown in FIG. As shown in FIG. 26, this is the amount of displacement of the lie camera rotation screw (42) in the AX or BX dimensional inspection error. For example, the length of the light receiving element (45) is about 40 mm, the distance between the light receiving element (45) and the sheet (2) in the Z direction is about 1000 mm, the rotation axis (47) of the bracket, the central axis, and the light receiving element ( 45) When the distance to the center is about 100 mm and the AX or BX dimensional inspection result is 0.75 mm, the line camera angle adjusting device (43) sets the line camera rotation screw (42) to the downstream side. The shape of the image (33) of the sheet (2) can be corrected by displacing .05 mm.

  As described above, the dimensional inspection error can be reduced by performing the automatic adjustment by the line camera mounting angle adjustment unit (23). However, when there is no device such as the motor (51), the line camera mounting angle adjustment section (23) displays the displacement amount of the line camera rotation screw (42) on the display section (20), and the operator As shown, the line camera rotation screw (42) is turned to adjust the line camera mounting angle.

  After adjusting the mounting angle of the line camera (8), the sheet (2) measured by the length measuring unit (19) is again passed through the cleaning position inspection device (1), and the calculation control unit A dimensional inspection error is calculated, and if the calculated dimensional inspection error in the X direction is out of the allowable range predetermined in the control unit (18), the adjustment by the line camera mounting angle adjusting unit (23) is performed again. . Note that the line camera attachment angle adjustment by the second and subsequent line camera attachment angle adjustment units (23) is smaller than the angle adjusted at the first time in order to prevent the rotation angle of the line camera from being over-controlled. Do

  Next, it demonstrates in detail using the operation | movement flow of an inspection precision adjustment apparatus (17) shown in FIG.

(Dimension measurement step, etc.)
As shown in FIG. 27, the inspection accuracy adjusting device (17) first measures the dimensions of the sheet (2) set in the length measuring section (19) (step (i)), and then the operator Puts the measured sheet (2) into the penetration position inspection device (1) and passes it through, and measures the dimension of the sheet (2) by the penetration position inspection device (1) (step ( ii)). Thereafter, the control unit (18) receives the dimensions of the sheet from the penetration position inspection device (1), and the dimension measurement value by the length measurement unit (19) and the dimension by the penetration position inspection device (1). An inspection error, which is a difference between measured values, is calculated (step (iii)).

(Inspection error calculation step (iii))
The control unit (18) determines the difference between the dimension measurement value of the sheet (2) by the length measurement unit (19) and the dimension measurement value of the same sheet (2) by the penetration position inspection device (1). When the dimensional inspection error of the penetration position inspection device (1) is within a predetermined tolerance range, it is found that the inspection function of the penetration position inspection device (1) is normal, and the penetration position The operation of the inspection device (1) is enabled, and the fact that it can be operated is displayed on the display unit (20). On the other hand, if the dimensional inspection error is outside the predetermined allowable range, the inspection function of the penetration position inspection device (1) is abnormal, and therefore the operation of the penetration position inspection device (1) is disabled. Further, it is displayed on the display unit (20) that driving is impossible. Next, the operation flow of each unit when adjusting the inspection error will be described.

(Resolution adjustment step (iv))
FIG. 28 is a resolution adjustment flow by the resolution adjustment unit (21) shown in FIG. 2 when the inspection function of the penetration position inspection apparatus (1) is abnormal. The resolution adjustment unit (21) receives the image (33) of the sheet (2) imaged by the penetration position inspection device (1), counts the number of pixels in the X direction and the Y direction, and measures the length. The optimal resolution of the line camera (8) in the X and Y directions is calculated by dividing by the dimension measurement values in the X and Y directions measured by the unit (19) (step (iv)). After the calculation, the calculated X- and Y-direction line camera resolutions are transmitted to the penetration position inspection apparatus (1) through the control unit (18).

  After setting the resolution of the line camera (8) by the resolution adjustment unit (21), the dimension inspection error of the sheet (2) is again investigated, and the dimension inspection error is outside the predetermined allowable range. Next, the press adjustment of the paper presser roller by the paper presser roller press adjusting unit (22) is performed (step (v)).

(Paper presser roller pressing adjustment step (v))
As shown in FIG. 29, the paper presser roller pressing adjustment unit (22) shown in FIG. 2 receives the Y-direction dimensional inspection error from the control unit (18). The difference of BY, which is a dimensional error on the side, is calculated. Next, referring to the paper pressing roller pressing database based on this difference, the pressing of the paper pressing roller (6) is changed (step (v)).

  After the adjustment of the pressure of the paper presser roller (6) by the paper presser roller press adjusting unit (22) is completed, the dimension inspection error is checked again, and the dimension inspection error in the Y direction is outside the predetermined allowable range. In this case, the paper presser roller press adjusting unit (22) first changes the press of the paper presser roller (6) to the reference press before adjustment.

(Paper presser roller mounting angle adjustment step (vi))
Next, as shown in FIG. 30, the paper presser roller mounting angle adjusting unit (23) shown in FIG. 2 receives the Y direction dimensional inspection error from the control unit (18), and the machine operation side dimensional error AY and machine The difference in dimensional error BY on the driving side is calculated. Next, referring to the paper presser roller mounting angle database based on this difference, the machine operation side bearing part (37) or the machine drive side bearing part (38) is slid in the Y direction, as shown in FIG. The angle of the paper presser roller mounting shaft (14) is adjusted (step (vi)).

  After the adjustment by the paper presser roller mounting angle adjustment unit (23), the dimensional inspection error is checked again. If the dimensional inspection error in the Y direction is outside the predetermined allowable range, the dimensional inspection error in the Y direction is determined in advance. The paper presser roller mounting angle adjustment unit (23) is repeatedly adjusted until it falls within the predetermined allowable range (step (vi)), and the dimensional inspection errors in the X and Y directions are within the predetermined allowable values. If it is within the range, the operation of the penetration position inspection device (1) becomes possible.

(Line camera mounting angle adjustment step (vii))
However, in the case where only the dimensional inspection error in the X direction is out of the predetermined allowable range despite the repeated adjustment by the paper presser roller mounting angle adjusting section (23), as shown in FIG. The line camera mounting angle is adjusted by the mounting angle adjusting unit (24) (step (vii)). The line camera mounting angle adjustment unit (24) receives the dimensional inspection error in the X direction from the control unit (18), calculates the difference between the AX and BX dimensional inspection errors, and based on this difference, the line camera ( 8) The angle of the line camera (8) is adjusted with reference to the mounting angle database (step (vii)).

  After the adjustment by the line camera mounting angle adjustment unit (24), the dimensional inspection error in the X direction is checked again. If the dimensional inspection error in the X direction is outside the predetermined allowable range, the dimensional inspection error in the X direction. Until the line camera is within a predetermined allowable range, the line camera mounting angle adjusting unit (24) repeatedly adjusts the mounting angle of the line camera (8) (step (vii)). The above description is the operation of the inspection accuracy adjusting device (17).

DESCRIPTION OF SYMBOLS 1 Plowing position inspection apparatus 2 Sheet | seat 3 Upstream conveyor 4 Downstream conveyor 5 Paper pressing plate 6 Paper pressing roller 7 Illumination 8 Line camera 9 Inspection part 10 Whole surface belt 11 Roller 12 Encoder 13 Arm 14 Paper pressing roller attachment shaft 15 Paper presser roller mounting frame 16 Spring 17 Inspection accuracy adjusting device 18 Control unit 19 Measuring unit 20 Display unit 21 Resolution adjusting unit 22 Paper presser roller press adjusting unit 23 Paper presser roller mounting angle adjusting unit 24 Line camera mounting angle adjusting unit 25 Positioning means 26 Irradiation means 27 Imaging means 28 Processing means 29 Plowing 30 Installation board 31 Area camera illumination (for reflection)
32 Sheet image by length measurement unit 33 Sheet sheet transmission image by penetration position inspection device 34 Motor 35 Load sensor 36 Press controller 37 Machine operation side bearing unit 38 Machine drive side bearing unit 39 Motor 40 Shaft angle control Device 41 Bracket 42 Line camera rotation screw 43 Line camera angle adjustment device 44 Lens 45 Light receiving element 46 Frame 47 Rotating shaft 48 Bearing 49 Knob 50 Spring 51 Motor 52 Transparent glass 53 Area camera illumination (for transmission)
54 Area camera 55 Measuring computer

Claims (5)

Using an inspection accuracy adjustment device that has at least a length measurement unit, adjust the paper pressing roller that conveys the sheet by pressing it against the belt, and the line camera that captures the gap formed on the sheet. In the adjustment method of the penetration inspection device that accurately measures the insertion position,
(I) capturing a transmission image or a reflection image of the sheet in advance by the length measuring unit, and measuring the insertion position or the size of the sheet;
(Ii) A transmission image or a reflection image of the same sheet as the sheet measured in step (i) is captured by the line camera, and the insertion position or the size of the sheet is measured. Steps,
(Iii) Subtracting the crease position or the sheet size measured in step (ii) from the crease position or the sheet size measured in step (i) And a step of calculating an inspection error which is a difference in position or a difference in dimensions of the sheet.   (Iv) After performing the step (iii), the resolution of the line camera is calculated by dividing the clearance position or the sheet size measured in the step (i) by the number of pixels of the line camera. The method for adjusting a penetration inspection apparatus according to claim 1, further comprising a step of adjusting a resolution of the line camera.   3. The adjustment of the penetration inspection apparatus according to claim 2, further comprising a step of adjusting a pressure of the paper pressing roller with respect to a belt direction of the sheet after performing the step (iv). Method.   4. The penetration inspection apparatus according to claim 3, further comprising a step of adjusting a mounting angle of a paper presser roller mounting shaft with respect to a transport direction of the sheet after performing step (v). Adjustment method.   5. The adjustment of the penetration inspection apparatus according to claim 4, further comprising a step of adjusting an attachment angle of the line camera with respect to a conveyance direction of the sheet after performing the step (vi). Method.

Images