Thickness Detector

Abstract

To provide a thickness detection apparatus capable of reducing an influence of a vibration of a swing shaft member with a simple configuration.SOLUTION: The thickness detection apparatus that detects a thickness of a paper sheet 100 to be conveyed between a reference roller 60 and a plurality of detection rollers 12, based on an amount of relative displacement of the detection roller 12 to the reference roller 60, includes: a detection block 10 that rotatably supports the detection roller 12; a swing shaft member 50 that swingably supports the plurality of detection blocks 10; a biasing member 40 that biases the detection roller 12 toward the reference roller 60; and a sensor 30 that detects an amount of displacement of a portion 13 to be detected provided on the detection block 10 as the amount of relative displacement. The thickness detection apparatus is configured so that a crossing angle, which is an angle at which s first direction A1 parallel to a thrust force acting on the swing shaft member 50 when the paper sheet 100 intrudes between the reference roller 60 and the detection roller 12 and a second direction A2 which is a detection direction of the sensor when the amount of the relative displacement is detected are crossed each other, is greater than 45 degrees.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a thickness detection device. [Background technology]

[0002] Conventionally, a thickness detection device is used to detect the thickness of paper sheets such as banknotes. For example, in a banknote processing device, a thickness detection device is used to find counterfeit banknotes pasted together with tape or the like. The thickness detection device disclosed in Patent Document 1 is provided with a reference roller and a detection roller, and the reference roller and the detection roller are arranged facing each other so that their outer circumferential surfaces are in contact with each other. The position of the reference roller is fixed. The detection roller is rotatably supported by a detection block, and the detection block is configured to be able to swing around the central axis of a swing shaft member (referred to as a "support shaft" in the document). With this configuration, when a paper sheet passes between the reference roller and the detection roller, the detection roller swings upward. The thickness detection device detects the thickness of the paper sheet based on the amount of displacement of the detection roller relative to the reference roller (referred to as a "movement amount" in the document).

[0003] In the thickness detection device described in Patent Document 1, the detection rollers and detection blocks are supported by the swing shaft member in a state of being arranged in a horizontal row. In this configuration, when the conveying speed of the paper sheet becomes high, the impact when the paper sheet enters between the reference roller and the detection roller is transmitted from the detection roller to the swing shaft member via the detection block, and the central part of the swing shaft member in the longitudinal direction may vibrate. When the swing shaft member vibrates, noise due to the vibration of the swing shaft member is added to the displacement amount of the detection roller detected by the sensor (referred to as the "sensor part" in the document). Therefore, there is a risk that the output signal of the sensor is disturbed due to the vibration of the swing shaft member, and the accuracy of the thickness detection is reduced. As a means for solving this inconvenience, in the thickness detection device described in Patent Document 1, a support member is provided at approximately the central part in the longitudinal direction of the swing shaft member, and the vibration of the swing shaft member is suppressed by the support member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-172413 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the technology described in Patent Document 1, the support member makes the configuration complicated and increases costs. Also, a dead zone is generated within the detection width of the thickness detector by the width of the support member.

[0006] In view of the above problems, an object of the present invention is to provide a thickness detection device that can reduce the influence of vibration of a pivot member with a simpler configuration than conventional thickness detection devices. [Means for solving the problem]

[0007] The present invention is a thickness detection device that detects the thickness of a paper sheet transported between a reference roller and a plurality of detection rollers facing the reference roller based on a relative displacement amount of the detection roller with respect to the reference roller, and includes a detection block that rotatably supports at least one of the plurality of detection rollers, a swing shaft member that swingably supports the plurality of detection blocks, a biasing member for biasing the detection roller toward the reference roller, and a sensor that faces a detected portion provided on the detection block and detects the displacement amount of the detected portion as the relative displacement amount, and is configured so that an intersection angle, which is an angle between a first direction parallel to a thrust force acting on the swing shaft member when the paper sheet thrusts between the reference roller and the detection roller, and a second direction that is a detection direction of the sensor when detecting the relative displacement amount, is greater than 45 degrees. the detected part has a magnet that swings together with the detection block, the sensor has a first hall element and a second hall element arranged along the second direction, and is configured to detect a first distance that is a distance between the first hall element and the magnet and a second distance that is a distance between the second hall element and the magnet, and to detect a displacement amount of the detected part based on a difference between the first distance and the second distance, the first hall element and the second hall element are arranged side by side along a vertical direction perpendicular to a conveying direction in which the paper sheets are conveyed. is.

[0008] When a protruding force acts in the first direction, the oscillating shaft member tends to vibrate along the first direction. In the present invention, the second direction, which is the detection direction of the sensor, is configured to deviate from the first direction by more than 45 degrees. Therefore, even if the oscillating shaft member, the detection block, and the detected member vibrate along the first direction, the cross angle is greater than 45 degrees, so that the vibration amplitude of the detected member along the second direction is relatively small, and the noise caused by the protruding force in the sensor output is relatively small. Therefore, even if the longitudinal center portion of the oscillating shaft member is not supported by a support member as disclosed in Patent Document 1, the sensor can accurately detect the relative displacement amount of the detection roller based on the displacement amount of the detected portion. As a result, a thickness detection device that can reduce the influence of vibration of the oscillating shaft member with a simple configuration is realized compared to conventional thickness detection devices.

[0009] In the present invention, it is preferable that a component of the plunge force parallel to the second direction be smaller than a component of the plunge force perpendicular to the second direction.

[0010] According to this configuration, the sensor is configured to minimize the application of the protruding force in the detection direction. This makes it difficult for noise due to the protruding force to be added to the displacement of the detected part detected by the sensor. This enables the sensor to accurately detect the relative displacement of the detection roller based on the displacement of the detected part while reducing the effect of the protruding force.

[0012] According to this configuration, the first and second Hall elements are arranged side by side along the second direction as two Hall elements. The first Hall element detects a first distance between the first Hall element and the magnet, and the second Hall element detects a second distance between the second Hall element and the magnet. The sensor detects the displacement of the magnet (detected part) based on the difference between the first and second distances. In the present invention, the "difference between the first and second distances" includes both the difference between the first and second distances and the ratio between the first and second distances. When the magnet is displaced along the second direction, a change occurs in the difference between the first and second distances, and the displacement of the magnet is detected according to the change in the difference. When the oscillating shaft member vibrates along the first direction, the magnet approaches or moves away from the two Hall elements due to the vibration of the oscillating shaft member. At this time, the first distance and the second distance each change like a wave, but in the second direction, the proportion of the displacement of the magnet caused by the vibration of the oscillation shaft member is small, so the change in the difference between the first distance and the second distance is small compared to the change in each of the first distance and the second distance, which enables the sensor to accurately detect the relative displacement of the detection roller based on the displacement of the detected part in the second direction.

[0014] According to this configuration, the sensor detects the displacement of the detected part based on the distance between one Hall element and the magnet, so that when the magnet moves in the second direction, the distance between the Hall element and the magnet changes, and the change in the distance between the Hall element and the magnet is detected directly by the sensor. Even if the oscillating shaft member vibrates in the first direction, the proportion of the displacement of the magnet caused by the vibration of the oscillating shaft member in the second direction is small, so that the change in the distance between the Hall element and the magnet does not change significantly. This allows the sensor to accurately detect the relative displacement of the detection roller based on the displacement of the detected part in the second direction.

[0015] In the present invention, when viewed in the second direction, The first hall element and the second hall element is preferably located in a region inside the outer circumferential edge of the magnet.

[0016] With this configuration, even if the oscillating shaft member vibrates in the first direction, the Hall element is unlikely to move out of the area outside the outer periphery of the magnet, and the Hall element can always detect the magnet at an appropriate distance. This allows the sensor to stably detect the relative displacement of the detection roller.

[0017] The thickness detection device of the present invention is a thickness detection device that detects the thickness of a paper sheet transported between a reference roller and a plurality of detection rollers facing the reference roller based on a relative displacement amount of the detection roller with respect to the reference roller, and includes a detection block that rotatably supports at least one of the plurality of detection rollers, a swing shaft member that swingably supports the plurality of detection blocks, a biasing member for biasing the detection roller toward the reference roller, and a sensor that faces a detected portion provided on the detection block and detects the displacement amount of the detected portion as the relative displacement amount, and a central axis of the swing shaft member and a rotational axis of the detection roller are arranged such that the central axis of the swing shaft member and the ... block are arranged such that the central axis of the swing shaft member and the rotational axis of the detection block are arranged such that the central axis of the swing shaft member and the rotational axis of the detection roller are arranged such that the central axis of the swing shaft member and the rotational axis of the detection block are arranged such that the central axis of the swing shaft member and the rotational axis of the detection block are arranged such that the central axis of the swing shaft member and the rotational axis of the detection block are arranged such that the central axis of the swing shaft member and the rotational axis of the detection block are arranged such that the central axis of the swing shaft member and the rotational axis of the detection block An inter-axial direction, which is a direction perpendicular to the rotation axis, intersects with a conveying direction in which the paper sheets are conveyed, the detected part has a magnet that swings together with the detection block, the sensor has a first hall element and a second hall element, and is configured to detect a first distance that is a distance between the first hall element and the magnet and a second distance that is a distance between the second hall element and the magnet, and to detect a displacement amount of the detected part based on a difference between the first distance and the second distance, the first hall element and the second hall element are arranged on the sensor along an arrangement direction that intersects with the inter-axial direction at an angle of greater than 45 degrees. The arrangement direction is perpendicular to the conveyance direction. is.

[0018] When a paper sheet enters between the reference roller and the detection roller, the thrust force may act in the interaxial direction between the central axis of the swing shaft member and the rotation axis of the detection roller. In the present invention, the first and second Hall elements are arranged so that the angle between the arrangement direction of the first and second Hall elements and the interaxial direction to which the thrust force is applied is greater than 45 degrees. A first distance between the first Hall element and the magnet is detected by the first Hall element, and a second distance between the second Hall element and the magnet is detected by the second Hall element. Then, based on the difference between the first and second distances, the sensor detects the displacement amount of the magnet (detected part). In the present invention, the "difference between the first and second distances" includes both the difference between the first and second distances and the ratio between the first and second distances. When the magnet is displaced along the arrangement direction, a change occurs in the difference between the first and second distances, and the displacement amount of the magnet is detected according to the change in the difference. When the oscillating shaft member vibrates along the interaxial direction, the magnet moves closer to or farther from the two Hall elements due to the vibration of the oscillating shaft member. At this time, the first distance and the second distance each change like a wave, but in the arrangement direction, the proportion of the displacement of the magnet caused by the vibration of the oscillating shaft member is small, so the change in the difference between the first distance and the second distance is smaller than the change in the first distance and the second distance. For this reason, even if the oscillating shaft member vibrates due to the protruding force, noise due to the vibration of the oscillating shaft member is less likely to be added to the displacement of the detected part detected by the sensor, compared to the case where the angle between the arrangement direction of the first hall element and the second hall element and the interaxial direction in which the protruding force is applied is 45 degrees or less. For this reason, even if the oscillating shaft member does not have a configuration in which the central part in the longitudinal direction is supported by a support member as disclosed in Patent Document 1, the sensor can accurately detect the relative displacement of the detection roller based on the displacement of the detected part. As a result, a thickness detection device that can reduce the influence of the vibration of the oscillating shaft member with a simple configuration is realized compared to the conventional thickness detection device.

[0019] The thickness detection device of the present invention is a thickness detection device that detects the thickness of a paper sheet transported between a reference roller and a plurality of detection rollers arranged above the reference roller based on the relative displacement of the detection roller with respect to the reference roller, and includes a detection block that rotatably supports at least one of the plurality of detection rollers, a swing shaft member that swingably supports the plurality of detection blocks, a biasing member for biasing the detection roller toward the reference roller, and a sensor located in front of a detected portion provided at a front end of the detection block and that detects the displacement of the detected portion as the relative displacement amount; the detected part has a magnet that oscillates together with the detection block at a height position overlapping with the oscillating shaft member in the vertical direction, the sensor has a first Hall element and a second Hall element, and is configured to detect a first distance that is a distance between the first Hall element and the magnet and a second distance that is a distance between the second Hall element and the magnet, and to detect a displacement amount of the detected part based on a difference between the first distance and the second distance, the first Hall element and the second Hall element being arranged in a vertical line on the sensor at a height position overlapping with the oscillating shaft member in the vertical direction.

[0020] The inventor of the present application found through analysis that when a paper sheet enters between the reference roller and the detection roller, the thrust force acts stronger in the paper sheet transport direction than in a direction perpendicular to the paper sheet transport direction. For this reason, the swing shaft member vibrates strongly along the paper sheet transport direction. In the present invention, the reference roller and the multiple detection rollers are arranged vertically side by side, and the first Hall element and the second Hall element are arranged vertically side by side. For this reason, with a simple configuration, it is possible to make the arrangement direction of the first Hall element and the second Hall element closer to the direction perpendicular to the direction in which the thrust force acts. In a state in which the reference roller and the multiple detection rollers are arranged vertically side by side, the paper sheet transport direction becomes horizontal or close to horizontal. A first distance, which is the distance between the first Hall element and the magnet, is detected by the first Hall element, and a second distance, which is the distance between the second Hall element and the magnet, is detected by the second Hall element. Then, based on the difference between the first distance and the second distance, the sensor detects the displacement amount of the magnet (detected portion). In the present invention, the "difference between the first distance and the second distance" includes both the difference between the first distance and the second distance and the ratio between the first distance and the second distance. The magnet is provided at a height position overlapping with the swing shaft member, and the first hall element and the second hall element are located forward of the magnet. With this configuration, the sensor detects the vertical displacement of the magnet (detected part). That is, when the magnet is displaced in the vertical direction, a change occurs in the difference between the first distance and the second distance, and the displacement of the magnet is detected according to the change in the difference. At this time, when the swing shaft member vibrates along the conveying direction of the paper sheets, the magnet vibrates along the conveying direction due to the vibration of the swing shaft member, and moves closer to or farther away from the two hall elements. The values ​​of the first distance and the second distance change like a wave, but in the vertical direction, the proportion of the displacement of the magnet caused by the vibration of the swing shaft member is small, so the change in the difference between the first distance and the second distance is smaller than the change in the values ​​of the first distance and the second distance. For this reason, compared to a configuration in which the first hall element and the second hall element are arranged along the transport direction of the paper sheets, even if the oscillating shaft member vibrates due to a thrust force, noise caused by the vibration of the oscillating shaft member is less likely to be added to the amount of displacement of the detected part detected by the sensor.Therefore, the sensor can accurately detect the relative displacement amount of the detection roller based on the displacement amount of the detected part, even if the longitudinal center portion of the oscillating shaft member is not supported by a support member as disclosed in Patent Document 1. This realizes a thickness detection device that can reduce the influence of vibration of the oscillating shaft member with a simpler configuration than conventional thickness detection devices.

[0021] In the present invention, it is preferable that the swing shaft member is disposed downstream of the reference roller and the plurality of detection rollers in a conveying direction of the paper sheet.

[0022] The inventor of the present application found through analysis that, in the conveying direction of the paper sheet, when the swing shaft member is arranged upstream of the reference roller and the detection roller, the detection roller and the detection block are more likely to swing, and when the swing shaft member is arranged downstream of the reference roller and the detection roller, the detection roller and the detection block are less likely to swing. When the paper sheet enters between the reference roller and the detection roller, the impact of the entry causes the detection roller to momentarily move upward from the paper sheet, so that an overshoot occurs in the relative displacement amount of the detection roller detected by the sensor. With this configuration, since the swing shaft member is arranged downstream of the reference roller and the detection roller, the detection roller and the detection block are less likely to swing compared to a configuration in which the swing shaft member is arranged upstream of the reference roller and the detection roller, and an overshoot in the relative displacement amount of the detection roller detected by the sensor is suppressed. As a result, even when the paper sheet enters between the reference roller and the detection roller, the sensor can accurately detect the relative displacement amount of the detection roller. [Brief description of the drawings]

[0023] [Figure 1] FIG. 2 is a schematic diagram showing a configuration of a thickness detection device. [Diagram 2] 13A and 13B are diagrams showing a support structure of a support shaft member that supports a plurality of detection blocks. [Diagram 3] FIG. 2 is a principle diagram showing a relationship between a first direction and a second direction. [Figure 4]FIG. 2 is a principle diagram showing a relationship between a first direction and a second direction. [Diagram 5] 11 is a graph showing a comparison of waveforms of relative displacement amounts between the conventional technique and this embodiment. FIG. [Figure 6] FIG. 2 is a schematic diagram showing a configuration of a thickness detection device equipped with a scraper. [Figure 7] 13 is a diagram showing the arrangement of a scraper and a cam, and their positional relationship with a detection block. FIG. [Figure 8] FIG. 4 is a schematic diagram showing the movement of a scraper. [Figure 9] 1A to 1C are schematic diagrams showing scrapers of different forms. [Figure 10] 1A to 1C are schematic diagrams showing scrapers of different forms. [Figure 11] 1A to 1C are schematic diagrams showing scrapers of different forms. [Figure 12] 1A to 1C are schematic diagrams showing scrapers of different forms. [Figure 13] FIG. 13 is a schematic diagram showing another embodiment of the thickness detection device. [Figure 14] FIG. 13 is a schematic diagram showing another embodiment of the thickness detection device. [Figure 15] FIG. 13 is a schematic diagram showing another embodiment of the thickness detection device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] [Configuration of thickness detection device] A preferred embodiment of the thickness detection device will be described in detail below with reference to the accompanying drawings. Fig. 1 is a schematic diagram for explaining a method for detecting the thickness of a paper sheet 100 by the thickness detection device. Note that the arrow "U" shown in Fig. 1 indicates the upward direction, and the arrow "D" shown in Fig. 1 indicates the downward direction. The arrows "U" and "D" indicate the positional relationship in the up-down direction. The arrows "U" and "D" in Fig. 2 and subsequent figures have the same meaning.

[0025] As shown in FIG. 1, the thickness detection device includes a reference roller 60 and a plurality of detection rollers 12. A sheet 100 to be subjected to thickness detection is transported in a direction indicated by a transport direction A3 along a transport path 70. The sheet 100 passes between the reference roller 60 and the detection roller 12 while being sandwiched between the detection roller 12 and the reference roller 60. At this time, the detection roller 12 rotates clockwise on the paper surface in FIG. 1, and the reference roller 60 rotates counterclockwise on the paper surface in FIG. 1. The rotation directions of the detection roller 12 and the reference roller 60 are the same in FIGS. 1 to 12. The thickness detection device detects the relative displacement amount of the plurality of detection rollers 12 with respect to the reference roller 60 when the sheet 100 passes between the reference roller 60 and the detection roller 12, thereby detecting the thickness of the sheet 100.

[0026] In this embodiment, in order to detect the thickness over the entire surface of the target paper sheet 100, a plurality of detection rollers 12 are arranged in an area wider than the width of the paper sheet 100 transported along the transport path 70 (see FIG. 2). Note that the width for which the thickness detection device detects the thickness of the paper sheet 100 can be set arbitrarily.

[0027] The reference roller 60 and the multiple detection rollers 12 are arranged facing each other in the vertical direction. When no paper sheet 100 is present between the reference roller 60 and the detection roller 12, the outer circumferential surface of each of the multiple detection rollers 12 comes into contact with the outer circumferential surface of the reference roller 60.

[0028] The reference roller 60 is rotatably supported by a rotating shaft member 61, and the position of the reference roller 60 is fixed. Therefore, even if a paper sheet 100 is sandwiched between the reference roller 60 and the detection roller 12, the position of the reference roller 60 does not change.

[0029] The detection roller 12 is rotatably supported by a pivot shaft member 11. The pivot shaft member 11 is fixed to the lower part of the detection block 10. The detection block 10 is made of, for example, a metal material or a resin material, and is pivotally supported by the pivot shaft member 50. Thus, the detection roller 12 is configured to be pivotable around the central axis of the pivot shaft member 50. The pivot shaft member 50 is disposed upstream of the reference roller 60 and the multiple detection rollers 12 in the conveying direction A3 of the paper sheet 100. When the paper sheet 100 is sandwiched between the reference roller 60 and the detection roller 12, the detection roller 12 pivots upward. In other words, the detection roller 12 is configured to be displaceable relative to the reference roller 60.

[0030] As described above, the thickness detection device detects the thickness of the paper sheet 100 based on the relative displacement of the detection roller 12 with respect to the reference roller 60. The "relative displacement" is the displacement of the detection roller 12 when the paper sheet 100 is sandwiched between the detection roller 12 and the reference roller 60, based on the position of the detection roller 12 when the outer circumferential surface of the reference roller 60 and the outer circumferential surface of the detection roller 12 are in contact with each other.

[0031] As described above, the detection block 10 is supported by the swing shaft member 50 so as to be swingable. Specifically, as shown in FIG. 1, a through hole is formed in the detection block 10, and a tubular sleeve 14 is inserted and fixed in the through hole. The sleeve 14 is made of a metal material. In the central axial direction of the swing shaft member 50, the sleeve 14 is configured to be longer than the detection block 10, and both ends of the sleeve 14 are exposed to the outside with respect to the detection block 10. The sleeve 14 fits onto the swing shaft member 50 and functions as a bearing member for the swing shaft member 50. Both ends of the swing shaft member 50 are fixed to the holding block 20 (see FIG. 2). In the conveying direction A3 of the paper sheet 100, the swing shaft member 50 is located upstream of the rotating shaft member 11 supporting the detection roller 12.

[0032] As shown in FIG. 1, a protrusion 10A is formed in a portion of the detection block 10 located above the detection roller 12. The upper surface of this protrusion 10A is biased downward by a leaf spring 40 (the "biasing member" of the present invention). One end of the leaf spring 40 is fixed to the holding block 20, and the other end of the leaf spring 40 contacts the protrusion 10A. With this configuration, the leaf spring 40 biases the holding block 20 downward, biasing the detection roller 12 toward the reference roller 60. Note that the biasing member is not limited to the leaf spring 40, and may be a member using another type of spring or rubber or the like. In other words, the biasing member may be any member that biases the detection roller 12 toward the reference roller 60.

[0033] When there is no paper sheet 100 between the detection roller 12 and the reference roller 60, the outer circumferential surface of the detection roller 12 is urged downward by the leaf spring 40 and pressed against the outer circumferential surface of the reference roller 60. When the paper sheet 100 conveyed along the conveying path 70 enters between the detection roller 12 and the reference roller 60, the detection roller 12 is pushed upward. At this time, the detection block 10 oscillates around the central axis of the oscillating shaft member 50 against the urging force of the leaf spring 40.

[0034] A detectable portion 13 is provided on the convex portion 10A of the detection block 10. The detectable portion 13 is provided on a surface portion of the convex portion 10A on the downstream side in the conveying direction A3 of the paper sheet 100. The detectable portion 13 has a magnet, and swings together with the detection block 10. The magnet provided on the detectable portion 13 may be a permanent magnet or an electromagnet.

[0035] The detected part 13 is displaced as the detection block 10 swings around the central axis of the swing shaft member 50. A sensor 30 is provided downstream of the detected part 13 in the conveying direction A3 of the paper sheet 100. The sensor 30 faces the detected part 13 provided on the detection block 10, and detects the amount of displacement of the detected part 13 as the amount of relative displacement of the detection roller 12 with respect to the reference roller 60.

[0036] In this embodiment, the sensor 30 has two Hall elements 31, which are arranged in a vertical direction. The Hall elements 31 are configured to output a signal indicating the distance between the magnet of the detected part 13. In this embodiment, one of the two Hall elements 31 is referred to as a "first Hall element 31a," and the other of the two Hall elements 31 is referred to as a "second Hall element 31b." Although the two Hall elements 31 are arranged in a vertical direction in Figs. 1, 6 to 10, and 12, the first Hall element 31a and the second Hall element 31b may be arranged either above or below.

[0037] In a configuration in which the sensor 30 has the first hall element 31a and the second hall element 31b, a difference occurs between the distance between the first hall element 31a and the detected part 13 (the "first distance" of the present invention) and the distance between the second hall element 31b and the detected part 13 (the "second distance" of the present invention). In addition, when the detected part 13 is displaced, the first distance and the second distance change, and the signals output from the first hall element 31a and the second hall element 31b change. At this time, the difference between the signals output from the first hall element 31a and the second hall element 31b also changes. The sensor 30 detects the amount of displacement of the detected part 13 by detecting the difference between the signals output from the first hall element 31a and the second hall element 31b. In other words, the sensor 30 is configured to detect the first distance and the second distance, and to detect the amount of displacement of the detected part 13 based on the difference between the first distance and the second distance (which may be the difference between the first distance and the second distance, or the ratio between the first distance and the second distance). With this configuration, the sensor 30 detects the amount of relative displacement of the detection roller 12 with respect to the reference roller 60 .

[0038] When the sheet 100 enters between the detection roller 12 and the reference roller 60, the detection roller 12 is pushed up by the thickness of the sheet 100. As the detection roller 12 is pushed up, the detection block 10 swings and the position of the detected part 13 changes. When the position of the detected part 13 changes, the signals output from the two Hall elements 31 change. Based on the amount of change in the signal, the sensor 30 can detect the amount by which the detection roller 12 is pushed up by the sheet 100, i.e., the thickness of the sheet 100. After the sheet 100 passes between the detection roller 12 and the reference roller 60, the detection block 10 is pushed down by the leaf spring 40, and the outer circumferential surface of the detection roller 12 returns to a state of contact with the outer circumferential surface of the reference roller 60.

[0039] 2 is a diagram showing a method of supporting the oscillating shaft member 50 to which multiple detection blocks 10 are attached. FIG. 2 shows a view of the detection block 10 as viewed from the right side of FIG. 1. Both axial ends of the sleeve 14 extend slightly outward from the main body of the detection block 10. Therefore, as shown in the partially enlarged view of FIG. 2, the end faces of adjacent sleeves 14 come into contact with each other, but adjacent detection blocks 10 do not come into contact with each other. When one detection block 10 oscillates, no frictional force acts from one detection block 10 to the other detection block 10, so the risk of the other detection block 10 swinging unexpectedly is avoided.

[0040] Both ends of the oscillating shaft member 50 are fixed to the holding block 20, and the holding block 20 functions as a holding portion that holds both ends of the oscillating shaft member 50. A plurality of detection blocks 10 are attached to the oscillating shaft member 50, both ends of which are fixed to the holding block 20. The plurality of detection blocks 10 are arranged in parallel along the longitudinal direction of the oscillating shaft member 50.

[0041] 2, a compression spring 51 is attached between each of the two detection blocks 10 and the retaining block 20 on both axially outer sides of the oscillating shaft member 50. The compression springs 51 bias the sleeves 14 of the detection blocks 10 from both outer sides in the axial direction (thrust direction) of the oscillating shaft member 50.

[0042] In this embodiment, two detection rollers 12 are attached to one detection block 10. The detection rollers 12 are arranged side by side in a direction perpendicular to the conveying direction A3 of the paper sheet 100. One or more reference rollers 60 are arranged facing each detection roller 12 and are provided along a direction parallel to the longitudinal direction of the swing shaft member 50. The detection rollers 12 are arranged over a range wider than the width of the paper sheet 100 along which the paper sheet 100 is conveyed. That is, the detection rollers 12 are arranged in a range exceeding the length (width) of the paper sheet 100 in the conveying path width direction (longitudinal direction of the swing shaft member 50) perpendicular to the conveying direction A3 of the paper sheet 100. In other words, the detection rollers 12 are arranged so that the distance between the two detection rollers 12 arranged on both outer sides in the arrangement direction is greater than the length (width) of the paper sheet 100 in the direction perpendicular to the conveying direction A3. Of the multiple detection rollers 12, the detection roller 12 at the position where the paper sheet 100 passes is pushed up, causing the detection block 10 to swing. The sensor 30 detects the thickness of the paper sheet 100 based on the displacement of the detection block 10.

[0043] For example, when tape is affixed to the sheet 100, the amount of swinging displacement of the detection roller 12 pushed up by the portion of the sheet 100 with the tape affixed is greater by the thickness of the tape than the amount of swinging displacement of the detection roller 12 pushed up by the portion of the sheet 100 without the tape. In other words, the thickness detection device is configured to be able to identify the position of the tape affixed to the sheet 100 by detecting, among the multiple detection blocks 10, the detection block 10 that has swung an extra large amount by the thickness of the tape. In this way, the thickness detection device is configured to be able to detect that tape is affixed to the sheet 100 based on the amount of swinging displacement of the detection block 10.

[0044] [Sensor detection direction] The detection rollers 12 and the detection blocks 10 are supported by the swing shaft member 50 in a state where multiple detection rollers 12 and detection blocks 10 are arranged in a horizontal row. In this configuration, when the conveying speed of the paper sheet 100 becomes high, an impact may occur when the paper sheet 100 enters between the reference roller 60 and the detection roller 12. This impact is transmitted from the detection roller 12 to the swing shaft member 50 via the detection block 10. Then, the central portion of the swing shaft member 50 in the longitudinal direction may vibrate due to the impact. When the swing shaft member 50 vibrates, noise due to the vibration of the swing shaft member 50 is added to the displacement amount of the detection roller 12 detected by the sensor 30. Therefore, there is a risk that the output signal of the sensor 30 will be disturbed due to the vibration of the swing shaft member 50, and the accuracy of thickness detection will decrease.

[0045] As described above, the sensor 30 detects the amount of displacement of the detected portion 13 based on the difference between the distance between the first Hall element 31a and the detected portion 13 (the "first distance" of the present invention) and the distance between the second Hall element 31b and the detected portion 13 (the "second distance" of the present invention). Therefore, the closer the direction in which the detected portion 13 is displaced is to the parallel direction of the first Hall element 31a and the second Hall element 31b, the more accurately the sensor 30 can detect the amount of relative displacement of the detection roller 12 with respect to the reference roller 60. The parallel direction of the first Hall element 31a and the second Hall element 31b is referred to as the detection direction A2 in this embodiment.

[0046] The inventor of the present application analyzed the vibration of the oscillating shaft member 50 and found that the oscillating shaft member 50 vibrates strongly in a specific direction. The direction in which the oscillating shaft member 50 vibrates strongly is parallel to the direction in which a thrust force acts on the oscillating shaft member 50 when a paper sheet 100 enters between the reference roller 60 and the detection roller 12, and this direction is shown as the action direction A1 in FIG. 1. The action direction A1 is the "first direction" of the present invention. The greater the deviation of this first direction from the detection direction A2 of the sensor 30, the less likely noise due to the vibration of the oscillating shaft member 50 will be added to the output signal of the sensor 30, and the accuracy of thickness detection will improve. The detection direction A2 of the sensor 30 is the "second direction" of the present invention.

[0047] In Fig. 3, the action direction A1, which is a first direction, and the detection direction A2, which is a second direction, intersect at right angles (or approximately at right angles). When the oscillating shaft member 50 vibrates along the action direction A1, the detected part 13 moves closer to or farther away from the two Hall elements 31 due to the vibration of the oscillating shaft member 50. At this time, the first distance and the second distance each change like a wave, but in the detection direction A2, the proportion of the displacement of the detected part 13 caused by the vibration of the oscillating shaft member 50 is small, so the change in the difference between the first distance and the second distance is smaller than the change in the first distance and the second distance. In this state, the sensor 30 is least susceptible to the influence of the vibration of the oscillating shaft member 50, and the accuracy of thickness detection is most improved.

[0048] Ideally, the sensor 30 and the detected part 13 are arranged so that the acting direction A1 and the detection direction A2 are perpendicular to each other. However, due to factors such as the relationship of space allocation for components in the thickness detection device and limited costs, it is often difficult to arrange the sensor 30 and the detected part 13 so that the acting direction A1 and the detection direction A2 are perpendicular to each other. For this reason, as shown in FIG. 4, even if the acting direction A1 and the detection direction A2 are not perpendicular to each other, it is preferable that the acting direction A1 and the detection direction A2 intersect at an intersection angle close to perpendicular to each other. In FIG. 4, a component force A12 parallel to the second direction (detection direction A2) and a component force A11 perpendicular to the second direction are shown as components of the thrust force acting in the acting direction A1. In the embodiment shown in FIG. 4, the component force A12 parallel to the second direction is configured to be smaller than the component force A11 perpendicular to the second direction. This configuration makes it possible to make it difficult for the vibration of the oscillating shaft member 50 to affect the sensor 30 as much as possible. It is preferable that the crossing angle, which is the angle at which the action direction A1 (first direction) and the detection direction A2 (second direction) cross, is greater than 45 degrees. For this reason, the thickness detection device is configured so that the crossing angle, which is the angle at which the first direction and the second direction cross, is greater than 45 degrees.

[0049] As a result of analysis, the inventor of the present application has found that when the paper sheet 100 enters between the reference roller 60 and the detection roller 12, a protruding force acts stronger in the conveying direction A3 of the paper sheet 100 than in a direction perpendicular to the conveying direction A3 of the paper sheet 100. In the thickness detection device shown in FIG. 1, a protruding force acts on the swing shaft member 50 in a direction from the rotating shaft member 11 of the detection roller 12 to the swing shaft member 50. The direction of this protruding force is a direction perpendicular to the central axis of the swing shaft member 50 and the rotation axis of the detection roller 12 (the "inter-axial direction" of the present invention). When the paper sheet 100 enters between the reference roller 60 and the detection roller 12, a protruding force acts stronger in this inter-axial direction. This inter-axial direction is the action direction A1, which is a first direction parallel to the protruding force acting on the swing shaft member 50 when the paper sheet 100 enters between the reference roller 60 and the detection roller 12. The thickness detection device is configured so that the angle at which the first direction intersects with the conveying direction A3 of the paper sheet 100 is smaller than 45 degrees.

[0050] In Fig. 1, two Hall elements 31 are arranged vertically along the movement direction of the detected part 13, and the detection direction A2 of the sensor 30 extends vertically. The movement direction of the detected part 13 is the detection direction A2 of the sensor 30, which is the second direction when detecting the relative displacement amount of the detection roller 12 with respect to the reference roller 60. In other words, the first Hall element 31a and the second Hall element 31b are arranged along the second direction. The thickness detection device is configured so that the cross angle between this second direction and the conveying direction A3 of the paper sheet 100 is orthogonal or approximately orthogonal.

[0051] With this configuration, the thickness detection device is configured so that the crossing angle between the first direction, which is the acting direction A1 in which the thrust force acts on the oscillating shaft member 50, and the second direction, which is the detection direction A2 of the sensor 30, is greater than 45 degrees. In the embodiment shown in Fig. 1, the first hall element 31a and the second hall element 31b are arranged along a direction (the "arrangement direction" of the present invention) that crosses the above-mentioned "inter-axial direction" at an angle greater than 45 degrees. In other words, the acting direction A1 and the detection direction A2 are configured to deviate from each other by greater than 45 degrees.

[0052] FIG. 5 is a graph comparing the output waveform of the sensor 30, that is, the waveform of the relative displacement amount of the detection roller 12 with respect to the reference roller 60, between this embodiment and the prior art. The vertical axis of the graph in FIG. 5 is the relative displacement amount, and the horizontal axis is time. The waveform shown by the solid line is the output waveform of the prior art, and the waveform shown by the dashed line is the waveform of this embodiment. The prior art is a thickness detection device shown in the above-mentioned Patent Document 1 from which the "support member 80" has been removed. In the thickness detection device of Patent Document 1, the detected part 13 is provided at the upper end of the detection block 10, and two Hall elements 31 face the detected part 13 while being lined up on the left and right. In the thickness detection device of Patent Document 1, the detection direction A2 of the sensor 30 is approximately the same as the conveying direction A3 of the paper sheet 100.

[0053] According to the knowledge of the inventor of the present application, when the paper sheet 100 enters between the reference roller 60 and the detection roller 12, the thrust force acts stronger in the conveying direction A3 of the paper sheet 100 than in the direction perpendicular to the conveying direction A3 of the paper sheet 100. For this reason, as shown by the solid line in FIG. 5, the output waveform of the conventional technology shows an overshoot at the time of rising and an undershoot immediately thereafter. On the other hand, as shown by the dashed line in FIG. 5, the output waveform of the present embodiment shows an overshoot at the time of rising, but the undershoot immediately thereafter is suppressed compared to the conventional technology, and further the convergence thereafter is improved. For this reason, the thickness detection device of the present embodiment has improved thickness detection accuracy even when compared to a configuration in which the "support member 80" is removed from the thickness detection device shown in the above-mentioned Patent Document 1. This makes it possible to achieve both thickness detection accuracy and cost reduction.

[0054] [Embodiment with scraper] Another embodiment will be described below with reference to Fig. 6 to Fig. 12. When a sheet 100 with foreign matter such as dust or sticky matter adhering thereto passes through the conveying path 70, the foreign matter may be transferred from the sheet 100 to the outer circumferential surface of the reference roller 60. When a foreign matter adheres to the outer circumferential surface of the reference roller 60, the foreign matter may push up the detection roller 12, disturbing the output waveform of the sensor 30, possibly resulting in false detection or reduced accuracy in thickness detection.

[0055] 6 to 12, a scraper 80 is provided below the reference roller 60. When viewed in the conveying direction A3 of the paper sheet 100, a lower half of the reference roller 60 overlaps with the scraper 80. The scraper 80 is in sliding contact with the outer circumferential surface of the reference roller 60 and is configured to be able to remove foreign matter such as dust adhering to the outer circumferential surface of the reference roller 60.

[0056] 6 to 12, a thin plate-shaped scraper 90 is supported by the detection block 10. The scraper 90 is for removing foreign matter adhering to the outer circumferential surface of the detection roller 12 as the detection roller 12 rotates. The scraper 90 contacts the detection roller 12 perpendicularly or approximately perpendicularly, and is capable of removing foreign matter adhering to the outer circumferential surface of the detection roller 12 regardless of the direction of rotation of the detection roller 12.

[0057] As shown in Fig. 7, the thickness detection device is provided with a plurality of scrapers 80. The number of scrapers 80 is the same as the number of detection blocks 10, and a scraper 80 is provided corresponding to each detection block 10. Each of the plurality of scrapers 80 is supported by a leaf spring 82. The leaf spring 82 may be configured to be supported by the holding block 20, or may be supported by a member other than the holding block 20 in the thickness detection device. In other words, the scraper 80 is supported by a predetermined member in the thickness detection device.

[0058] A cam 81 is provided adjacent to the scraper 80 and the leaf spring 82 below, and the multiple cams 81 are supported by a cam shaft member 83. When the cam shaft member 83 rotates, the multiple cams 81 rotate integrally with the cam shaft member 83. A protruding portion 81A is formed on the outer peripheral surface of the cam 81. As shown in FIG. 8, the protruding portion 81A of the cam 81 abuts against the leaf spring 82 every time it rotates. When the cam 81 abuts against the leaf spring 82, the leaf spring 82 is pushed upward from below by the cam 81 and elastically deforms, and the scraper 80 comes into sliding contact with the outer peripheral surface of the reference roller 60. When the protruding portion 81A of the cam 81 leaves the leaf spring 82, the leaf spring 82 returns to its original shape, and the scraper 80 leaves the reference roller 60.

[0059] The scraper 80 slides against the outer circumferential surface of the reference roller 60, thereby removing foreign matter such as dust adhering to the outer circumferential surface of the reference roller 60. This stabilizes the output waveform of the sensor 30. As a result, the accuracy of thickness detection is easily maintained, and erroneous detection is less likely to occur.

[0060] It is preferable that the scraper 80 is configured to come into sliding contact with the reference roller 60 at a timing other than the low-temperature start-up of the thickness detection device. For this reason, the scraper 80 may be configured to come into sliding contact with the reference roller 60 at a timing other than the low-temperature start-up.

[0061] If all the scrapers 80 come into sliding contact with the reference roller 60 at the same time, the sliding resistance of the scrapers 80 increases, and the rotational load of the reference roller 60 increases. For this reason, the thickness detection device of this embodiment is configured so that the timing of each scraper 80 coming into sliding contact with the reference roller 60 is shifted. Specifically, in the rotation direction of the cam 81, the protruding portions 81A to 81H of each cam 81 are arranged with an angle shifted so as to be out of phase with the protruding portions of the other cams 81.

[0062] 6 to 8, the protrusions 81A-81H of each cam 81 are shifted in phase by 45 degrees. As shown in Fig. 7, 16 cams 81 are provided along the longitudinal direction of a cam shaft member 83, and two of each cam 81 have protrusions 81A-81H in the same phase.

[0063] It is assumed that a pressing force of F Newtons acts on the reference roller 60 when the protruding parts 81A to 81H of all the cams 81 face in the same direction and the protruding parts 81A to 81H are in sliding contact with the reference roller 60 at the same time. In the embodiment shown in FIG. 7, the number of the cams 81 that are in sliding contact with the reference roller 60 at the same time is two, so the pressing force acting on the reference roller 60 is (F / 8) Newtons. In addition, when the protruding parts of all the cams 81 are out of phase with each other relative to the protruding parts of the other cams 81, each protruding part is in sliding contact with the reference roller 60 one by one during one rotation of the cam shaft member 83, so the pressing force acting on the reference roller 60 is (F / 16) Newtons. As a result, compared to a configuration in which all the scrapers 80 are in sliding contact with the reference roller 60 at the same time, the sliding resistance of the scraper 80 is reduced, and the rotation load of the reference roller 60 is reduced.

[0064] 6 to 8, the number of cams 81 that simultaneously come into sliding contact with the reference roller 60 is two, but this is not limited to this embodiment. For example, the number of cams 81 that simultaneously come into sliding contact with the reference roller 60 may be one or three. Furthermore, the cam 81 may be, for example, an eccentric roller.

[0065] 9 to 12 show another embodiment of the scraper 80. In the embodiment shown in FIG. 9 and FIG. 10, the scraper 80 and the linking mechanism 84 are connected to a support shaft member 88, and the scraper 80 and the linking mechanism 84 swing together around the central axis of the support shaft member 88. The scraper 80 and the linking mechanism 84 are separated by the support shaft member 88. The linking mechanism 84 is inclined so that the free end side is positioned upward, and the free end 84A is located in the conveying path 70. A biasing member 85 is provided in a portion between the base end and the free end 84A of the linking mechanism 84, and the biasing member 85 biases the linking mechanism 84 and the scraper 80 to swing counterclockwise on the paper surface of FIG. 9 and FIG. 10. Although the biasing member 85 is shown as a coil spring in FIG. 9 and FIG. 10, the biasing member 85 may be, for example, a leaf spring, a sponge member, or the like. As shown in Fig. 9, when the paper sheet 100 is conveyed along the conveying path 70 and comes into contact with the free end 84A of the linking mechanism 84, the linking mechanism 84 and the scraper 80 swing clockwise in Fig. 10 against the biasing force of the biasing member 85. Then, the scraper 80 comes into sliding contact with the outer circumferential surface of the reference roller 60. When the paper sheet 100 passes through the conveying path 70 and is no longer in contact with the free end 84A of the linking mechanism 84, the linking mechanism 84 and the scraper 80 swing counterclockwise in Figs. 9 and 10 due to the biasing force of the biasing member 85. Then, the scraper 80 comes out of sliding contact with the outer circumferential surface of the reference roller 60.

[0066] In the embodiment shown in Figs. 11 and 12, a linking mechanism 86 is connected to a support shaft member 89, and a scraper 80 is connected to a free end 86A of the scraper 80. The distance between the scraper 80 and the support shaft member 89 is longer than the distance between the linking mechanism 86 and the support shaft member 89. The scraper 80 and the linking mechanism 86 swing together around the central axis of the support shaft member 89. The linking mechanism 84 is inclined so as to be positioned upward toward the free end, and the free end 86A is located in the conveying path 70. The scraper 80 is located below the conveying path 70. A biasing member 87 is provided between the base end and the free end 86A of the linking mechanism 86, and the biasing member 87 biases the linking mechanism 86 and the scraper 80 to swing clockwise on the paper surface of Figs. 11 and 12. 9 and 10, the biasing member 85 is shown as a coil spring, but the biasing member 85 may be, for example, a leaf spring, a sponge member, or the like. As shown in FIG. 12, when the paper sheet 100 is conveyed along the conveying path 70, when the paper sheet 100 comes into contact with the free end 86A of the linking mechanism 86, the linking mechanism 86 and the scraper 80 swing counterclockwise in FIG. 12 against the biasing force of the biasing member 87. Then, the scraper 80 slides against the outer circumferential surface of the reference roller 60. When the paper sheet 100 passes through the conveying path 70 and is no longer in contact with the free end 86A of the linking mechanism 86, the linking mechanism 86 and the scraper 80 swing clockwise in FIG. 11 and 12 due to the biasing force of the biasing member 87. Then, the scraper 80 no longer slides against the outer circumferential surface of the reference roller 60. In the embodiment shown in FIGS. 11 and 12, the scraper 80 may also be used as a guide member for guiding the paper sheet 100 between the reference roller 60 and the detection roller 12.

[0067] When the thickness detection device is started, the motor provided in the device needs to generate a large torque. When the device is at a low temperature, an even larger torque is required. The performance of the motor is determined according to the torque required for starting. In the case where the reference roller 60 and the scraper 80 are in contact with each other, the torque required for starting is even larger, so the performance of the motor driving the reference roller 60 needs to be improved. In the embodiment shown in Figs. 9 to 12, the reference roller 60 and the scraper 80 do not come into contact with each other when the paper sheet 100 does not pass through the conveying path 70. Therefore, the increase in the torque required for starting is suppressed. Since there is no need to increase the performance of the motor, the increase in costs is suppressed. In addition, in this embodiment, the timing when the reference roller 60 and the scraper 80 come into contact with each other is limited to the timing when the paper sheet 100 passes through the conveying path 70, so the durability of the scraper 80 is improved.

[0068] In addition to the embodiment shown in Figs. 9 to 12, for example, a non-contact sensor may be provided in the middle of the conveying path 70, and an actuator may be provided to control the scraper 80 based on a detection signal from the non-contact sensor. In this case, the non-contact sensor detects the passage of the paper sheet 100, and the actuator is configured to be able to switch between a state in which the scraper 80 is in sliding contact with the reference roller 60 and a state in which the scraper is not in sliding contact with the reference roller 60 based on the detection by the non-contact sensor. In addition, the scraper 80 shown in Figs. 6 to 12 may be configured to be in sliding contact with the reference roller 60 only at the timing when the reference roller 60 or the like reaches an appropriate temperature after the completion of low-temperature start-up of the thickness detection device, the timing of initial processing of the thickness detection device, the timing of the end of one transaction, or the timing of the end of business for one day.

[0069] [Another embodiment] The present invention is not limited to the configurations exemplified in the above-described embodiments, and other representative embodiments of the present invention will be described below.

[0070] (1) As shown in FIG. 13, the sensor 30 may have only one Hall element 32. In the thickness detection device shown in FIG. 13, a plurality of detection blocks 10 are arranged in parallel on one oscillating shaft member 50, similar to the embodiment shown in FIG. 2, and the detection block 10 is provided with two detection rollers 12 and one detected part 16. The detected part 16 has a magnet and oscillates together with the detection block 10. The magnet provided on the detected part 16 may be a permanent magnet or an electromagnet. Although not shown, the detection block 10 is urged to oscillate downward by an urging member (not shown). Also, although the scraper 80 is omitted in FIG. 13, the embodiment shown in FIG. 13 may be provided with the scraper 80.

[0071] A protruding force acts on the swing shaft member 50 in a direction from the rotating shaft member 11 of the detection roller 12 to the swing shaft member 50. In FIG. 13, the direction of this protruding force is shown as an action direction A1. The action direction A1 is an interaxial direction perpendicular to the central axis of the swing shaft member 50 and the rotation axis of the detection roller 12. When a paper sheet 100 enters between the reference roller 60 and the detection roller 12, a strong protruding force acts in the action direction A1. The action direction A1 is a first direction parallel to the protruding force acting on the swing shaft member 50 when the paper sheet 100 enters between the reference roller 60 and the detection roller 12.

[0072] In the embodiment shown in Fig. 13, the detectable portion 16 and the Hall element 32 are arranged along a direction perpendicular or substantially perpendicular to the action direction A1. The detectable portion 16 swings together with the detection block 10 and moves along the detection direction A2 of the sensor 30. The detection direction A2 is a second direction. The upper surface portion of the detectable portion 16 acts toward and away from the Hall element 32. The sensor 30 has one Hall element 32 and detects the amount of displacement of the detectable portion 16 based on the distance between the Hall element 32 and the detectable portion 16. In other words, the movement direction of the magnet of the detectable portion 16 is the second direction.

[0073] 13, when viewed in the second direction (detection direction A2), the Hall element 32 is located in an area inside the outer periphery of the detected portion 16. Therefore, even when the oscillating shaft member 50 vibrates along the first direction, the distance between the upper surface of the detected portion 16 and the Hall element 32 hardly changes due to the vibration of the oscillating shaft member 50. This improves the accuracy of thickness detection.

[0074] (2) In the embodiment shown in Fig. 14, the detected part 13 is provided at the front end of the detection block 10. The detected part 13 has a magnet that oscillates together with the detection block 10 at a height position overlapping with the oscillating shaft member 50 in the vertical direction. The magnet provided on the detected part 13 may be a permanent magnet or an electromagnet. Note that the convex part 10B of the detection block 10 has a configuration similar to the convex part 10A shown in Fig. 1 etc., and the upper surface part of the convex part 10B is urged downward by the leaf spring 40.

[0075] The sensor 30 is located in front of the detected part 13 provided at the front end of the detection block 10, and detects the displacement of the detected part 13 as the relative displacement of the detection roller 12 with respect to the reference roller 60. The sensor 30 also has a first hall element 31a and a second hall element 31b arranged vertically side by side at a height position overlapping with the oscillating shaft member 50 in the vertical direction. The sensor 30 is configured to detect a first distance, which is the distance between the first hall element 31a and the magnet of the detected part 13, and a second distance, which is the distance between the second hall element 31b and the magnet, and to detect the displacement of the detected part 13 based on the difference between the first distance and the second distance.

[0076] The swing shaft member 50 strongly vibrates along the conveying direction A3 of the paper sheet 100. When the swing shaft member 50 vibrates along the conveying direction A3 of the paper sheet 100, the magnet of the detected part 13 vibrates along the conveying direction A3 due to the vibration of the swing shaft member 50, and moves closer to or farther away from the two Hall elements 31. The values ​​of the first distance and the second distance change like a wave, but in the vertical direction, the proportion of the displacement of the magnet caused by the vibration of the swing shaft member 50 is small, so the change in the difference between the first distance and the second distance is small compared to the change in each value of the first distance and the second distance. Therefore, in the configuration shown in FIG. 14, even if the swing shaft member 50 vibrates due to the thrust force, noise due to the vibration of the swing shaft member 50 is less likely to be added to the displacement of the detected part 13 detected by the sensor 30 compared to a configuration in which the first hall element 31a and the second hall element 31b are aligned along the conveying direction A3 of the paper sheet 100.

[0077] (3) In the above embodiment, the detection block 10 rotatably supports two detection rollers 12. However, the present invention is not limited to this embodiment, and the detection block 10 may be configured to support one detection roller 12, or three or more detection rollers 12.

[0078] (4) In the above embodiment, the sensor 30 has a Hall element 31, and the detected part 13 has a magnet. However, this is not limited to the embodiment, and for example, the sensor 30 may have an optical sensor such as a laser sensor, and the detected part 13 may have a mirror that reflects light irradiated from the optical sensor.

[0079] (5) In the above-described embodiment, the swing shaft member 50 is disposed upstream of the reference roller 60 and the plurality of detection rollers 12 in the conveying direction A3 of the paper sheet 100. This embodiment is not limited to this, and the swing shaft member 50 may be disposed downstream of the reference roller 60 and the plurality of detection rollers 12 in the conveying direction A4 of the paper sheet 100, as shown in FIG.

[0080] The paper sheet 100 is transported along the transport path 70 in a direction indicated by a transport direction A4. The transport direction A4 is the opposite direction to the transport direction A3 shown in FIG. 1 and the like. The paper sheet 100 passes between the detection roller 12 and the reference roller 60 while being sandwiched between the detection roller 12 and the reference roller 60. At this time, the detection roller 12 rotates counterclockwise on the paper in FIG. 15, and the reference roller 60 rotates clockwise on the paper in FIG. 15.

[0081] When the paper sheet 100 enters between the reference roller 60 and the detection roller 12, the detection roller 12 is momentarily separated upward from the paper sheet 100 by the impact of the entry, so that an overshoot occurs in the relative displacement amount of the detection roller 12 detected by the sensor 30. According to the knowledge of the inventor of the present application, when the swing shaft member 50 is arranged downstream of the reference roller 60 and the detection roller 12 in the conveying direction A4 of the paper sheet 100, the detection roller 12 and the detection block 10 are less likely to swing compared to a configuration in which the swing shaft member 50 is arranged upstream of the reference roller 60 and the detection roller 12. With this configuration, the detection roller 12 and the detection block 10 are less likely to swing, and an overshoot in the relative displacement amount of the detection roller 12 detected by the sensor 30 is suppressed. As a result, even when the paper sheet 100 enters between the reference roller 60 and the detection roller 12, the sensor 30 can accurately detect the relative displacement amount of the detection roller 12.

[0082] The configurations disclosed in the above-mentioned embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, unless a contradiction occurs. In addition, the embodiments disclosed in this specification are merely examples, and the present invention is not limited to these embodiments, and can be appropriately modified within the scope of the present invention. [Industrial Applicability]

[0083] The present invention is applicable to a thickness detection device that detects the thickness of a paper sheet transported between a reference roller and a plurality of detection rollers based on the amount of relative displacement of the detection roller with respect to a reference roller. [Explanation of symbols]

[0084] 10: Detection block 12: Detection roller 13: Detected part 16: Detected part 30: Sensor 31: Hall element 31a: First Hall element 31b: Second Hall element 32: Hall element 40: Leaf spring (biasing member) 50: Swing shaft member 60: Reference roller 100: Paper sheets A1: Direction of action (first direction) A2: Detection direction (second direction) A3: Transport direction A4: Transport direction

Claims

1. A thickness detection device that detects the thickness of a sheet transported between a reference roller and a plurality of detection rollers facing the reference roller based on a relative displacement amount of the detection rollers with respect to the reference roller, a detection block that rotatably supports at least one of the plurality of detection rollers; a swing shaft member that swingably supports the plurality of detection blocks; a biasing member for biasing the detection roller toward the reference roller; a sensor that faces a detectable portion provided on the detection block and detects a displacement amount of the detectable portion as the relative displacement amount, a crossing angle between a first direction parallel to a thrust force acting on the pivot shaft member when the paper sheet enters between the reference roller and the detection roller and a second direction which is a detection direction of the sensor when detecting the relative displacement is configured to be greater than 45 degrees, The detected part has a magnet that swings together with the detection block, the sensor has a first hall element and a second hall element arranged along the second direction, and is configured to detect a first distance that is a distance between the first hall element and the magnet and a second distance that is a distance between the second hall element and the magnet, and to detect a displacement amount of the detected portion based on a difference between the first distance and the second distance; The thickness detection device, in which the first hall element and the second hall element are arranged side by side along a vertical direction perpendicular to a conveying direction in which the paper sheets are conveyed.

2. The thickness detection device according to claim 1 , wherein a component of the plunge force parallel to the second direction is smaller than a component of the plunge force perpendicular to the second direction.

3. The thickness detection device according to claim 1 , wherein the first Hall element and the second Hall element are located in an area inside an outer periphery of the magnet when viewed in the second direction.

4. A thickness detection device that detects the thickness of a sheet transported between a reference roller and a plurality of detection rollers facing the reference roller based on a relative displacement amount of the detection rollers with respect to the reference roller, a detection block that rotatably supports at least one of the plurality of detection rollers; a swing shaft member that swingably supports the plurality of detection blocks; a biasing member for biasing the detection roller toward the reference roller; a sensor that faces a detectable portion provided on the detection block and detects a displacement amount of the detectable portion as the relative displacement amount, an inter-axial direction perpendicular to a central axis of the pivot shaft member and a rotation axis of the detection roller intersects with a conveying direction in which the paper sheets are conveyed; The detected part has a magnet that swings together with the detection block, the sensor has a first hall element and a second hall element, and is configured to detect a first distance that is a distance between the first hall element and the magnet and a second distance that is a distance between the second hall element and the magnet, and to detect a displacement amount of the detected portion based on a difference between the first distance and the second distance; the first hall element and the second hall element are arranged in the sensor along an arrangement direction that intersects with the interaxial direction at an angle of greater than 45 degrees; The thickness detection device, wherein the arrangement direction is perpendicular to the conveying direction.

5. A thickness detection device that detects the thickness of a sheet transported between a reference roller and a plurality of detection rollers facing the reference roller based on a relative displacement amount of the detection rollers with respect to the reference roller, a detection block that rotatably supports at least one of the plurality of detection rollers; a swing shaft member that swingably supports the plurality of detection blocks; a biasing member for biasing the detection roller toward the reference roller; a sensor located in front of a detectable portion provided at a front end of the detection block and configured to detect a displacement amount of the detectable portion as the relative displacement amount, the detected portion has a magnet that oscillates together with the detection block at a height position that overlaps with the oscillating shaft member in the up-down direction, the sensor has a first hall element and a second hall element, and is configured to detect a first distance that is a distance between the first hall element and the magnet and a second distance that is a distance between the second hall element and the magnet, and to detect a displacement amount of the detected portion based on a difference between the first distance and the second distance; The thickness detection device, wherein the first hall element and the second hall element are arranged vertically side by side on the sensor at a height position overlapping with the oscillating shaft member in the vertical direction.

6. 6. The thickness detection device according to claim 1, wherein the pivot shaft member is disposed downstream of the reference roller and the plurality of detection rollers in a conveying direction of the paper sheet.

Images