Thickness measurement apparatus and thickness measurement method

Abstract

A thickness measurement apparatus (10) according to the present invention has a first guide roller (11), a second guide roller (12), and a sensor unit (20). The sensor unit (20) has a sensor shaft part (21), a contact roller (22) that is rotatably held at the tip of the sensor shaft part (21), a block part (23), and a detection unit that detects an amount of displacement of the contact roller (22) with respect to the block part (23). The block part (23) is provided so as to be movable along a direction approaching or separating from the contact roller (22), and when measuring a thickness, the block part (23) comes into contact with one surface of a conveyed sheet member (1), and the contact roller (22) comes into contact with the other surface of the conveyed sheet member (1) so that the conveyed sheet member (1) is sandwiched between the block part (23) and the contact roller (22). Thus, the present invention can measure the thickness of the sheet member (1) stably while conveying the sheet member (1).

Description

Thickness measuring device and thickness measuring method

[0001] The present invention relates to a thickness measuring device and a thickness measuring method for measuring the thickness of a sheet member having a structure integrally provided on one surface of a support portion.

[0002] Conventionally, hook-and-loop fastener products have been known in which a loop member (female hook-and-loop fastener) having a plurality of loops is combined with a male hook-and-loop fastener that is detachable from the loop member. The male hook-and-loop fastener (hereinafter simply referred to as hook-and-loop fastener) has, for example, a thin plate-like base portion and a plurality of engaging elements that protrude from the base portion and have a mushroom-like or other shape. Such a hook-and-loop fastener can also be said to be a sheet member in which structures (engaging elements) are integrally provided on one surface of a support portion (base portion).

[0003] For example, International Publication No. 2017 / 109902 (Patent Document 1) discloses a hook-and-loop fastener used in disposable diapers and the like. The hook-and-loop fastener described in Patent Document 1 has a thin plate-shaped base portion and a plurality of engaging elements protruding from the base portion. Each engaging element in Patent Document 1 has a stem portion rising from the base portion and a disk-shaped engaging head portion integrally formed at the upper end of the stem portion. In addition, the engaging head portion is provided with a plurality of tiny claw portions protruding from the outer peripheral edge portion of the engaging head portion.

[0004] When manufacturing the hook-and-loop fastener of Patent Document 1, a primary molding step is first carried out. In this primary molding step, a molten thermoplastic resin is continuously extruded onto the outer peripheral surface of a rotating die wheel to form a primary molded body having a base portion and a plurality of primary elements provided on the base portion.

[0005] The primary molded body having a plurality of primary elements is then conveyed to a heating and pressing device that performs a secondary molding process. In this secondary molding process, the primary molded body is introduced between a pair of upper and lower rollers of the heating and pressing device, whereby the upper roller presses and deforms the upper end portions of the primary elements, thereby forming engaging elements having engaging heads from the primary elements. By performing this secondary molding process, the sheet-like hook-and-loop fastener described in Patent Document 1 is manufactured.

[0006] International Publication No. 2017 / 109902

[0007] In recent years, when manufacturing sheet-like hook-and-loop fasteners, there has been a demand for reducing the thickness between the upper surface (first surface) and the lower surface (second surface) of the base portion in order to reduce the manufacturing cost of the hook-and-loop fastener and to improve the flexibility of the hook-and-loop fastener. However, in the primary molding process using the above-mentioned die wheel, there is a limit to how thin the thickness of the base portion molded on the outer circumferential surface of the die wheel can be made.

[0008] Therefore, in order to reduce the thickness of the base portion, it is conceivable to carry out a stretching process in which the hook-and-loop fastener obtained by the secondary molding process is transported to a stretching device, and the base portion is stretched in the machine direction (transport direction) while being heated in the stretching device. By introducing such a stretching process after the secondary molding process, the hook-and-loop fastener can be stretched in the machine direction, and therefore the overall thickness of the hook-and-loop fastener can be reduced compared to before the stretching process.

[0009] When such a stretching step is performed, the secondary-molded surface fastener is directly transported to a stretching device, and the secondary molding step and the stretching step are performed continuously, thereby improving the efficiency of the manufacturing process and the productivity. In order to make the thickness of the surface fastener after stretching uniform, it is preferable that the thickness of the surface fastener before the stretching step (i.e., the surface fastener obtained by performing the secondary molding step) is uniform.

[0010] However, in the secondary molding process in which the primary molded body is heated and pressed, the surface fastener is easily affected by the heat during secondary molding, which can cause problems such as the thickness of the surface fastener becoming unstable in the machine direction.

[0011] For this reason, when the secondary molding step and the stretching step are performed, it is conceivable to measure the thickness of the hook-and-loop fastener after the secondary molding step and feed the measurement result back to the secondary molding step, thereby making the thickness of the hook-and-loop fastener obtained after the secondary molding step uniform. In this case, however, it is required to measure the thickness of the secondarily molded hook-and-loop fastener while transporting it between the secondary molding step and the stretching step.

[0012] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a thickness measuring device and a thickness measuring method that can measure the thickness of a sheet member having a structure integrally attached to a support part such as a hook-and-loop fastener while transporting the sheet member.

[0013] In order to achieve the above object, the present invention provides a thickness measuring device that measures the thickness of a sheet member having a support portion on one side thereof as the sheet member is transported, the thickness measuring device comprising: a first guide roller that contacts the sheet member; a second guide roller that is arranged downstream of the first guide roller and that contacts the sheet member; and a sensor unit that is arranged between the first guide roller and the second guide roller, the sensor unit comprising a sensor shaft portion, a contact roller that is rotatably held at the tip of the sensor shaft portion, a block portion that supports the sheet member, and a detection unit that detects the amount of displacement of the contact roller relative to the block portion, the contact roller and the block portion being arranged on opposite sides of the transport path of the sheet member, and the block portion being movable in directions approaching and moving away from the contact roller, and when measuring the thickness, the block portion comes into contact with one side of the sheet member being transported, and the contact roller comes into contact with the other side of the sheet member being transported, thereby sandwiching the sheet member being transported between the block portion and the contact roller.

[0014] In the thickness measuring device of the present invention, it is preferable that the block portion is held away from the conveyance path of the sheet member when the thickness is not being measured.

[0015] Furthermore, when the first guide roller and the second guide roller are arranged so as to contact the sheet material from the side where the structure is formed, and the direction in which the block portion approaches and moves away from the contact roller is defined as the vertical direction, the block portion is arranged to be movable in the vertical direction between a first position that is arranged below the respective lower end positions of the first guide roller and the second guide roller, and a second position that is arranged above the respective lower end positions, and when the thickness is not being measured, the block portion is held at the first position, and the contact roller is held at a position above and away from the conveying path of the sheet material, in a state where it is not in contact with the sheet material, and when the thickness is being measured, it is preferable that the block portion is held at the second position, thereby contacting the sheet material being conveyed from below and applying tension to the sheet material between the first guide roller and the second guide roller, and the contact roller contacts the sheet material to which the tension has been applied, from above. In this case, it is preferable that the block portion has a support surface that supports the sheet member, and that the support surface of the block portion has a plane that is perpendicular to the up-down direction.

[0016] In the present invention, it is also preferable that the contact roller is formed in a cylindrical shape, and that when measuring the thickness, the block portion contacts the sheet member from the side opposite to the surface on which the structure is formed, and the contact roller contacts the sheet member from the side on which the structure is formed.

[0017] Furthermore, a cover portion that protects the sensor shaft portion and the contact roller is provided between the first guide roller and the second guide roller, and the cover portion has a shape such that the cross section when the cover portion is cut along the machine direction in which the sheet material is transported is approximately U-shaped, and it is preferable that the bottom portion of the cover portion has a hole portion that penetrates from the inner surface to the outer surface of the cover portion and through which the contact roller can be inserted.

[0018] Next, a thickness measurement method provided by the present invention is a thickness measurement method in which a sheet member having a structure integrally provided on one surface of a support portion is conveyed and the thickness of the sheet member is measured using a thickness measurement device, wherein the thickness measurement device has a first guide roller that contacts the sheet member, a second guide roller that is arranged downstream of the first guide roller and that contacts the sheet member, and a sensor unit that is arranged between the first guide roller and the second guide roller, and the thickness measurement method includes, when starting the thickness measurement, moving a block unit of the sensor unit to approach a contact roller of the sensor unit, bringing the block unit into contact with one surface of the sheet member being conveyed and bringing the contact roller into contact with the other surface of the sheet member, thereby sandwiching the sheet member being conveyed between the block unit and the contact roller, and detecting the amount of displacement of the contact roller relative to the block unit while the sheet member is sandwiched between the block unit and the contact roller, thereby measuring the thickness of the sheet member.

[0019] The thickness measuring method of the present invention preferably includes holding the block portion away from a conveyance path of the sheet member when the thickness is not being measured.

[0020] Furthermore, in the present invention, the first guide roller and the second guide roller are arranged so as to contact the sheet material from the side where the structure is formed, and when the direction in which the block portion approaches and moves away from the contact roller is defined as the up-down direction, the block portion is arranged to be movable in the up-down direction between a first position that is arranged below the respective lower end positions of the first guide roller and the second guide roller, and a second position that is arranged above the respective lower end positions, and the thickness measurement method preferably includes: when the thickness is not being measured, holding the block portion at the first position and holding the contact roller at a position above and away from the conveying path of the sheet material so as not to contact the sheet material; when the thickness is being measured, holding the block portion at the second position so as to bring the block portion into contact with the sheet material being conveyed from below, thereby applying tension to the sheet material between the first guide roller and the second guide roller; and bringing the contact roller into contact with the sheet material to which the tension has been applied from above.

[0021] According to the thickness measuring device and thickness measuring method of the present invention, the thickness of a sheet member such as a hook-and-loop fastener can be measured stably while the sheet member is being conveyed.

[0022] Fig. 2 is a cross-sectional view schematically showing a main part of a thickness measurement device according to an embodiment of the present invention. Fig. 3 is a diagram schematically showing an enlarged view of a part of a sensor unit in the thickness measurement device shown in Fig. 1. Fig. 4 is a cross-sectional view schematically showing a main part of the thickness measurement device during measurement. Fig. 5 is a perspective view schematically showing a main part of the thickness measurement device from an obliquely lower side during measurement.

[0023] For example, in the past, when manufacturing a hook-and-loop fastener such as that described in Patent Document 1, as mentioned above, a primary molding process in which a primary molded body is formed and a secondary molding process in which the primary molded body is heated and pressed by a heating and pressing device are carried out consecutively.

[0024] Incidentally, when a production line for manufacturing sheet materials such as hook-and-loop fasteners is stopped and then restarted, it is common to join together the end (upstream end) of the molded product that was formed when the production line was stopped and the end (downstream end) of the molded product that will be molded into the same shape after the production line is restarted. This allows the production line to operate as smoothly as before the stoppage after restarting.

[0025] In the case of a manufacturing process for a hook-and-loop fastener that includes the above-mentioned primary and secondary molding steps, the joining of the molded bodies during this restart is often carried out between the primary and secondary molding steps. Furthermore, when two molded bodies are joined together in this way, a connecting portion that directly connects the two molded bodies and an extending portion that extends from the connecting portion are formed at the joining portion of the molded bodies. In this case, the extending portion of the connecting portion is formed by a part of the molded bodies before they were joined.

[0026] In developing a technology for measuring the thickness of a sheet member, such as a hook-and-loop fastener, while the sheet member is being transported, the inventors came up with the idea of ​​measuring the thickness of the sheet member using a sensor unit equipped with a contact roller that directly contacts the sheet member. Furthermore, as a result of repeated experiments on a technology for measuring the thickness of a sheet member using a contact roller, the inventors found that the joint portion of the molded body described above is likely to get caught on the contact roller that contacts the sheet member when measuring the thickness of the sheet member, which can result in new problems (issues) such as interruptions to the thickness measurement or damage or malfunction of the contact roller. Therefore, the inventors conducted extensive experiments and studies, including efforts to resolve these new problems, and completed the present invention.

[0027] A preferred embodiment of the present invention will be described in detail below with reference to the drawings. Here, Fig. 1 is a cross-sectional view showing a main part of a thickness measurement device according to this embodiment. Fig. 2 is an enlarged schematic view showing a part of a sensor unit provided in the thickness measurement device.

[0028] In the following description, the machine direction (M direction or MD) refers to the direction along which a sheet member is conveyed in processes such as measuring the thickness of the sheet member and manufacturing the sheet member. The machine direction is the length direction of a long sheet member, and is also sometimes referred to as the front-to-rear direction. In this case, the downstream side of the machine direction is referred to as the rear, and the upstream side of the machine direction is referred to as the front. The cross direction (C direction or CD) refers to the width direction and left-to-right direction of the sheet member that are perpendicular to the machine direction and that run along the top surface (first surface) of the sheet member.

[0029] The thickness direction of the sheet member is the direction perpendicular to both the machine direction and the orthogonal direction, and is also sometimes referred to as the up-down direction. In this case, the side of the sheet member on which the structures (engagement elements) are provided relative to the support part (base part) is referred to as the up direction, and the opposite direction is referred to as the down direction.

[0030] The thickness measuring device 10 of this embodiment is a device for measuring the overall thickness in the vertical direction (thickness direction) of a sheet member 1. The sheet member 1 to be measured by this thickness measuring device 10 has a support portion and at least one structure provided on one surface of the support portion. It is preferable that the sheet member 1 has a plurality of structures integrally provided on the support portion. Such a sheet member 1 includes a hook-and-loop fastener 1, which will be described below. The following describes a case where the overall thickness of the hook-and-loop fastener 1 is measured using the thickness measuring device 10.

[0031] The hook-and-loop fastener 1 to be measured in this embodiment is one that is produced by, for example, a primary molding process using a die wheel and a secondary molding process using a heated press device. After the thickness of the hook-and-loop fastener 1 to be measured is measured by the thickness measuring device 10 shown in Fig. 1, it is continuously transported to a stretching device, where it is further stretched (stretching process) to stretch the hook-and-loop fastener 1 along the machine direction.

[0032] The hook-and-loop fastener 1 to be measured is made of a thermoplastic resin and is formed long along the machine direction (front-to-back direction). Although not specifically shown, the hook-and-loop fastener 1 has a thin plate-like base portion that serves as a support portion, and a plurality of engaging elements that stand up on the upper surface of the base portion as structures. In this case, the upper surface of the hook-and-loop fastener 1 is the surface on which the structures (engaging elements) of the hook-and-loop fastener 1 are formed. The lower surface of the hook-and-loop fastener 1 is the surface opposite to the surface on which the structures of the hook-and-loop fastener 1 are formed.

[0033] The base portion of the hook-and-loop fastener 1 has a flat upper surface and a flat lower surface located on the opposite side of the upper surface. A plurality of engaging elements protrude upward from the upper surface of the base portion. Each engaging element has a stem portion rising from the base portion and a disk-shaped engaging head portion integrally formed at the upper end of the stem portion. The engaging head portion is formed so as to protrude from the upper end of the stem portion entirely in a direction perpendicular to the height direction (vertical direction) of the stem portion. The engaging head portion may be provided with at least one minute engaging claw portion protruding outward from the outer peripheral edge of the engaging head portion. In the present invention, the hook-and-loop fastener 1 to be measured is not particularly limited in terms of its specific structure, as long as it has a base portion and a plurality of engaging elements integrally formed on the base portion.

[0034] The thickness measuring device 10 of this embodiment, which measures the thickness of the hook-and-loop fastener 1 as described above, is disposed between a heat pressing device that performs secondary molding and a stretching device that performs stretching in the manufacturing process of the hook-and-loop fastener 1. For example, the thickness measuring device 10 may be disposed adjacent to the downstream end of the heat pressing device, in a state where it is directly fixed to the heat pressing device.

[0035] In this case, the thickness measuring device 10 of this embodiment may be configured so that the measurement results obtained by the thickness measuring device 10 are fed back to a control unit that controls the processing conditions, etc. of the heat pressing device. As a result, if there is a variation in the thickness of the hook-and-loop fastener 1 measured by the thickness measuring device 10, for example, the heat pressing device can change the processing conditions, etc. in response to the variation, making it easier to stably control the thickness of the hook-and-loop fastener 1 obtained in the secondary molding process to a constant size.

[0036] As shown in Figure 1, the thickness measuring device 10 of this embodiment has a supply section (not shown) to which the hook-and-loop fastener 1 that has undergone the secondary molding process is supplied, a discharge section (not shown) that sends the hook-and-loop fastener 1 toward the stretching device after its thickness has been measured, and a first guide roller 11, a second guide roller 12, and a sensor section 20 arranged between the supply section and the discharge section.

[0037] The supply section (not shown) of the thickness measuring device 10 is configured to receive the hook-and-loop fastener 1 that has been secondary molded in the secondary molding step and send it out toward the first guide roller 11. The discharge section of the thickness measuring device 10 is configured to send the hook-and-loop fastener 1, the thickness of which has been measured by the sensor section 20, toward a downstream stretching device (not shown). Note that in the present invention, the supply section and discharge section of the thickness measuring device 10 are not particularly limited. For example, the supply section of the thickness measuring device 10 may be formed by a part of a heating and pressing device that performs the secondary molding step.

[0038] The first guide roller 11 and the second guide roller 12 of the thickness measuring device 10 are each rotatably installed at a predetermined position. The first guide roller 11 and the second guide roller 12 each have an outer circumferential surface that comes into contact with the hook-and-loop fastener 1. The first guide roller 11 and the second guide roller 12 have the same cylindrical shape and are formed to be the same size.

[0039] The first guide roller 11 and the second guide roller 12 are arranged at a distance from each other, and the first guide roller 11 is arranged upstream of the second guide roller 12 in the conveying path of the hook-and-loop fastener 1. In the present invention, the size (separation distance) of the separation between the first guide roller 11 and the second guide roller 12 is not particularly limited.

[0040] In this embodiment, the first guide roller 11 and the second guide roller 12 are installed parallel to each other at the same vertical position (height position). The lower ends of the outer circumferential surfaces of the first guide roller 11 and the second guide roller 12 are arranged at the same vertical height position. Note that the first guide roller 11 and the second guide roller 12 may be arranged at different vertical height positions or may be formed to have different sizes.

[0041] 1, the first guide roller 11 and the second guide roller 12 are each held so as to be rotatable in a counterclockwise direction at a position where their outer peripheral surfaces come into contact with the conveyance path of the hook-and-loop fastener 1 conveyed within the thickness measuring device 10 from the upper surface (the surface on which the engaging elements of the hook-and-loop fastener 1 are formed) of the hook-and-loop fastener 1. The first guide roller 11 and the second guide roller 12 may also be arranged at a position where they come into contact with the surface (for example, the lower surface) opposite to the surface on which the engaging elements of the hook-and-loop fastener 1 are formed.

[0042] The first guide roller 11 and the second guide roller 12 are provided with a rotation control unit (not shown), and this rotation control unit controls the rotation speed of the first guide roller 11 and the rotation speed of the second guide roller 12. In this embodiment, the rotation speeds of the first guide roller 11 and the second guide roller 12 are controlled to the same speed corresponding to the conveying speed of the hook-and-loop fastener 1.

[0043] 1, the sensor unit 20 is provided at a position between the first guide roller 11 and the second guide roller 12 in the machine direction. In order to measure the thickness of the hook-and-loop fastener 1, this sensor unit 20 uses a contact-type displacement sensor that directly contacts the hook-and-loop fastener 1 to be measured to measure the thickness of the hook-and-loop fastener 1. Because the sensor unit 20 is formed as a contact type, it becomes possible to measure with higher precision the thickness of the hook-and-loop fastener 1 that has a plurality of engaging elements protruding from its base portion.

[0044] 1 and 2 , the sensor unit 20 of this embodiment has a sensor shaft 21 arranged along the vertical direction, a contact roller 22 rotatably held at the tip (lower end) of the sensor shaft 21, a block 23 that supports the sheet member 1 from the underside, and a cover 24 that protects the sensor shaft 21 and the contact roller 22. Although not shown, the sensor unit 20 also has a position control unit that controls the position and vertical movement of the block 23, and a detection unit that detects the amount of displacement of the contact roller 22 relative to the block 23.

[0045] The sensor shaft 21 of the sensor unit 20 is installed straight in the vertical direction at a position midway between the first guide roller 11 and the second guide roller 12, and is installed at a position above the conveyance path of the hook-and-loop fastener 1. The sensor shaft 21 has a roller holding part 21a arranged at the lower end of the sensor shaft 21 (see FIG. 2), and the contact roller 22 is held by this roller holding part 21a so that it can rotate and move in the vertical direction.

[0046] The contact roller 22 of the sensor unit 20 has a cylindrical shape and is held by the sensor shaft unit 21 so that its rotation axis is parallel to the orthogonal direction (the width direction of the hook-and-loop fastener 1). This contact roller 22 is held by the roller holding unit 21a so as to be rotatable in clockwise and counterclockwise directions, for example, in Figures 1 and 2. This allows the contact roller 22 to rotate as the hook-and-loop fastener 1 is conveyed, while keeping the outer peripheral surface of the cylinder in stable contact with the upper surface of the hook-and-loop fastener 1.

[0047] Furthermore, because the contact roller 22 is formed in a cylindrical shape, a large area can be ensured in the width direction (orthogonal direction) over which the contact roller 22 comes into contact with the upper surface of the hook-and-loop fastener 1. As a result, even if the contact roller 22 is biased by an elastic member as described below, the pressure applied to the hook-and-loop fastener 1 from the upper surface side (the side on which the engaging elements are formed) can be appropriately distributed, preventing the hook-and-loop fastener 1 (particularly the engaging elements) from being crushed or even damaged by contact with the contact roller 22, and enabling the thickness of the hook-and-loop fastener 1 to be measured with high accuracy. The contact roller 22 may be formed in a spherical or other shape.

[0048] The sensor shaft 21 and contact roller 22 in this embodiment are arranged in a position in the orthogonal direction (the width direction of the hook-and-loop fastener 1) corresponding to the portion where the thickness of the hook-and-loop fastener 1 is to be measured. For example, in this embodiment, in order to measure the thickness at the center in the width direction of the hook-and-loop fastener 1, the sensor shaft 21 and contact roller 22 are arranged in a position in the orthogonal direction corresponding to the center of the hook-and-loop fastener 1. Note that in the present invention, the installation positions of the sensor shaft and contact roller in the orthogonal direction are not particularly limited and can be changed.

[0049] The contact roller 22 in this embodiment is held in a standby position by the sensor shaft 21 during non-measurement times when thickness measurement is not being performed, such as before the start of measurement of the thickness of the hook-and-loop fastener 1. The standby position of the contact roller 22 is disposed above the transport path of the hook-and-loop fastener 1, and is slightly separated from the hook-and-loop fastener 1 being transported.

[0050] By setting the standby position of the contact roller 22 away from the hook-and-loop fastener 1, even if a connecting portion (not shown) with an extension as described above is formed on the hook-and-loop fastener 1 being transported when not measuring, the connecting portion of the hook-and-loop fastener 1 is less likely to interfere with the contact roller 22, and the connecting portion can be easily sent downstream of the contact roller 22. Note that in the present invention, the standby position of the contact roller when not measuring may be set at a position where it comes into contact with the hook-and-loop fastener being transported.

[0051] The contact roller 22 in this embodiment is held by the sensor shaft 21 so as to be movable in the up-down direction from the above-mentioned preparation position upward. The contact roller 22 is also biased toward the conveyance path of the hook-and-loop fastener 1 (i.e., downward) by an elastic member (not shown) such as a coil spring.

[0052] When viewing a cross section perpendicular to the left-right direction of the cylindrical contact roller 22, the diameter of the contact roller 22 is set to a size that prevents a portion of the contact roller 22 from entering the gaps between engaging elements adjacent to each other in the machine direction of the hook-and-loop fastener 1 when the contact roller 22 comes into contact with the hook-and-loop fastener 1 during transport. For example, in the case of this embodiment, the contact roller 22 has a diameter of 5 mm or more and 20 mm or less.

[0053] Normally, an uneven shape is formed on the upper surface of the hook-and-loop fastener 1, with areas where engaging elements are provided and areas where engaging elements are not provided. In contrast, the contact roller 22 of this embodiment has the diameter described above, and therefore can prevent the contact roller 22 from getting between the engaging elements of the hook-and-loop fastener 1 when measuring the thickness of the hook-and-loop fastener 1 with the hook-and-loop fastener 1 sandwiched between the contact roller 22 and the block portion 23 in the vertical direction. This makes it possible to properly measure the overall thickness of the hook-and-loop fastener 1 along the machine direction without the contact roller 22 being affected by the uneven shape formed on the upper surface of the hook-and-loop fastener 1.

[0054] The block portion 23 of the sensor unit 20 is disposed at a position below the conveyance path of the hook-and-loop fastener 1. More specifically, the block portion 23 is disposed on the vertical opposite side of the contact roller 22 across the conveyance path of the hook-and-loop fastener 1, and at a position corresponding to the contact roller 22 in the machine direction. The block portion 23 is provided so as to be movable in the vertical direction by a position control portion (not shown) so that the hook-and-loop fastener 1 being conveyed can be directly sandwiched between the block portion 23 and the contact roller 22. Furthermore, the block portion 23 is formed long in the orthogonal direction, and can support the hook-and-loop fastener 1 to be measured across the entire width direction.

[0055] In a cross section of the block portion 23 cut along the machine direction (see FIG. 1 ), the block portion 23 of this embodiment has a support surface 23a that faces upward and supports the hook-and-loop fastener 1, a front end surface 23b and a rear end surface 23c that face the machine direction, and front and rear curved surfaces that extend while curving from the support surface 23a toward the front end surface 23b or the rear end surface 23c. The support surface 23a of the block portion 23 is formed as a flat plane that is perpendicular to the up-down direction. In this embodiment, the dimension of the support surface 23a along the machine direction is set to be 50% or more and 150% or less of the diameter of the contact roller 22.

[0056] As described above, since the support surface 23a is formed on the block portion 23, when the thickness of the hook-and-loop fastener 1 is measured, the hook-and-loop fastener 1 can be stably supported by the block portion 23 from the underside thereof during transport. Furthermore, since the front and rear curved surfaces are formed on the block portion 23, problems such as the hook-and-loop fastener 1 getting caught on the block portion 23 during transport are less likely to occur. Furthermore, when the thickness of the hook-and-loop fastener 1 is measured by sandwiching the hook-and-loop fastener 1 vertically between the contact roller 22 and the block portion 23, the position of the contact roller 22, which is disposed on the support surface 23a of the block portion 23 via the hook-and-loop fastener 1, can be stabilized, preventing the position of the contact roller 22 from shifting in the front-to-rear direction. This allows the thickness of the hook-and-loop fastener 1 to be measured accurately and stably by the contact roller 22 and the block portion 23.

[0057] The block portion 23 in this embodiment is provided so as to be movable toward and away from the contact roller 22 by a position control portion (not shown) of the sensor portion 20. Specifically, the block portion 23 is provided so as to be movable in the vertical direction between a standby position (first position) shown in Fig. 1 where the block portion 23 is held when the thickness of the hook-and-loop fastener 1 is not being measured, and a measurement position (second position) shown in Fig. 3 where the block portion 23 is held when the thickness of the hook-and-loop fastener 1 is being measured.

[0058] In this case, the standby position of the block portion 23 (particularly the position of the support surface 23a at the standby position) is set lower in the vertical direction than the lower end positions of the first guide roller 11 and the second guide roller 12, and is also arranged below and spaced apart from the transported hook-and-loop fastener 1 (the transport path of the hook-and-loop fastener 1). In this case, the standby position of the block portion 23 is set so that the vertical distance between the block portion 23 held at the standby position and the hook-and-loop fastener 1 is larger than the vertical distance between the contact roller 22 and the hook-and-loop fastener 1.

[0059] In this embodiment, the vertical distance between the block portion 23 held in the standby position and the hook-and-loop fastener 1 is set to 5 mm or more and 20 mm or less. The vertical distance between the contact roller 22 held in the preparation position and the hook-and-loop fastener 1 is set to 0.2 mm or more and 2 mm or less. This makes it possible to prevent the connecting portion of the hook-and-loop fastener 1 from getting caught on the block portion 23 even if the connecting portion (not shown) is formed on the hook-and-loop fastener 1 being transported when the thickness is not being measured.

[0060] The measurement position of the block portion 23 (particularly, the position of the support surface 23a at the measurement position) is set above the lower end positions of the first guide roller 11 and the second guide roller 12 in the vertical direction. Furthermore, the measurement position of the block portion 23 is set above the lower end position of the contact roller 22 held in the standby position. By setting the measurement position in this manner, for example, by moving the block portion 23 from the standby position to the measurement position using the position control unit, the support surface 23a of the block portion 23 can be brought into contact with the bottom side of the hook-and-loop fastener 1 during transport. Furthermore, the block portion 23 can lift a portion of the hook-and-loop fastener 1, which makes it easy to apply tension to the hook-and-loop fastener 1 during transport between the first guide roller 11 and the second guide roller 12.

[0061] Furthermore, by moving the block portion 23 to the measurement position, the contact roller 22, which is biased downward, can be lifted via the hook-and-loop fastener 1. This allows the contact roller 22 and the block portion 23 to stably sandwich the hook-and-loop fastener 1 in the vertical direction. As a result, by detecting the amount of displacement (displacement length) of the contact roller 22 relative to the block portion 23 in the detection portion of the sensor unit 20, the overall vertical dimension (thickness dimension) from the lower surface of the base portion of the hook-and-loop fastener 1 to the upper end position of the engaging element can be properly measured.

[0062] The cover portion 24 of the sensor unit 20 is provided between the first guide roller 11 and the second guide roller 12 to protect the sensor shaft portion 21 and the contact roller 22. The cover portion 24 is formed, for example, so that the cross section of the cover portion 24 when cut along the machine direction is generally U-shaped. That is, as shown in FIG. 2 , the cover portion 24 has a thin plate-like bottom surface portion 24a, a front vertical wall portion 24b that bends and extends upward from the front end of the bottom surface portion 24a, and a rear vertical wall portion 24c that bends and extends upward from the rear end of the bottom surface portion 24a. At least a portion of the sensor shaft portion 21 and at least a portion of the contact roller 22 are housed inside this generally U-shaped cover portion 24.

[0063] The bottom surface 24a of the cover part 24 is provided with one circular insertion hole 24d that penetrates from the inner surface to the outer surface of the bottom surface 24a. This insertion hole 24d is formed with a size that allows the insertion of the contact roller 22 and the roller holding part 21a that holds the contact roller 22. Note that, for example, if the sensor part is provided with a plurality of sensor shafts and contact rollers, the bottom surface of the cover part is provided with insertion holes in a number corresponding to the number of installed sensor shafts and contact rollers, corresponding to the installation positions of each sensor shaft and contact roller.

[0064] By providing such a cover portion 24, even if a connecting portion (not shown) is formed on the hook-and-loop fastener 1 being transported, the sensor shaft portion 21 and contact roller 22 arranged inside the cover portion 24 can be protected from the connecting portion of the hook-and-loop fastener 1, preventing the sensor shaft portion 21 and contact roller 22 from getting caught on the connecting portion of the hook-and-loop fastener 1.

[0065] Next, a method for measuring the thickness of the hook-and-loop fastener 1 using the thickness measuring device 10 of this embodiment will be described. Below, a case will be described in which the thickness of the hook-and-loop fastener 1 is measured while being transported, the hook-and-loop fastener 1 having been obtained by a primary molding process using a molding device equipped with a die wheel and a secondary molding process using a heating and pressing device.

[0066] In the thickness measurement method of this embodiment, before starting to measure the thickness of the hook-and-loop fastener 1 (i.e., when the thickness is not being measured), as shown in Fig. 1 , the hook-and-loop fastener 1 is conveyed from a supply section (not shown) of the thickness measurement device 10 toward a discharge section (not shown) while being guided by a first guide roller 11 and a second guide roller 12. At this time, the contact roller 22 of the sensor section 20 is held in a standby position above the conveyance path of the hook-and-loop fastener 1 and slightly spaced apart from the hook-and-loop fastener 1. The block section 23 is held in a standby position below the conveyance path of the hook-and-loop fastener 1 and spaced apart from the hook-and-loop fastener 1.

[0067] For example, when hook-and-loop fasteners 1 are joined together between the primary molding process and the secondary molding process in order to stop and then restart the production of the hook-and-loop fastener 1, as described above, a joint portion with an extension is formed on the hook-and-loop fastener 1. In this case, when the joint portion of the hook-and-loop fastener 1 passes through the thickness measuring device 10, if, for example, the contact roller 22 and the block portion 23 are in contact with the hook-and-loop fastener 1 being transported, the joint portion of the hook-and-loop fastener 1 may get caught on the contact roller 22 and / or the block portion 23. If the joint portion gets caught in this way within the thickness measuring device 10, the transport of the hook-and-loop fastener 1 within the thickness measuring device 10 may stop, making measurement impossible, and problems such as damage or malfunction of the contact roller 22 and / or the block portion 23 may occur.

[0068] To address such problems, in the thickness measurement method of this embodiment, both the contact roller 22 and the block portion 23 of the sensor portion 20 are held away from the hook-and-loop fastener 1 guided by the first guide roller 11 and the second guide roller 12 before measurement begins (non-measurement state). That is, the contact roller 22 is held above the transport path of the hook-and-loop fastener 1 and in a state of not contacting the hook-and-loop fastener 1. The block portion 23 is held below the transport path of the hook-and-loop fastener 1 and in a state of not contacting the hook-and-loop fastener 1. Furthermore, in this embodiment, the sensor shaft portion 21 and the contact roller 22 are protected by the cover portion 24, and the block portion 23 is held farther away from the transported hook-and-loop fastener 1 than the contact roller 22.

[0069] Therefore, in this embodiment, even if the above-mentioned connecting portion is formed on the hook-and-loop fastener 1, it is possible to prevent or suppress the connecting portion from getting caught on the contact roller 22 and the block portion 23 when the connecting portion of the hook-and-loop fastener 1 passes through the thickness measuring device 10 at a stage before the start of measurement, thereby making it less likely that problems will occur due to the connecting portion, such as a stop in the transport of the hook-and-loop fastener 1 and damage or malfunction of the contact roller 22 and the block portion 23. Note that in this embodiment, even if the hook-and-loop fastener 1 has a unique portion other than the above-mentioned connecting portion that may cause problems such as getting caught on the contact-type sensor portion 20, it is possible to make it less likely that problems will occur due to the unique portion.

[0070] In the thickness measurement method of this embodiment, the conveyance of the hook-and-loop fastener 1 continues, and measurement of the thickness of the hook-and-loop fastener 1 begins after the above-mentioned joint portion has been sent at least downstream in the machine direction from the position of the sensor unit 20. Note that, for example, if the hook-and-loop fastener 1 does not have any peculiar portion, such as a joint portion, that would cause a malfunction in the contact-type sensor unit 20, measurement of the thickness of the hook-and-loop fastener 1 can be started at any time as long as the hook-and-loop fastener 1 is in a conveyed state.

[0071] In this embodiment, when starting to measure the thickness, the block portion 23 held in a standby position in the thickness measuring device 10 is raised by a position control portion (not shown) of the sensor portion 20 to move it to the predetermined position shown in Fig. 3. This allows the block portion 23 to come into contact with (press against) the hook-and-loop fastener 1 being transported from the bottom surface (one surface) side, and the hook-and-loop fastener 1 to be supported by the support surface 23a of the block portion 23.

[0072] 3, the support surface 23a of the block portion 23 that has moved to the fixed position is positioned up and down higher than the lower end positions of the first guide roller 11 and the second guide roller 12. Therefore, the block portion 23 that has moved to the fixed position can lift up the hook-and-loop fastener 1 being conveyed at the center between the first guide roller 11 and the second guide roller 12.

[0073] As a result, tension is applied to the hook-and-loop fastener 1 at least between the contact portion with the first guide roller 11 and the contact portion with the second guide roller 12, thereby preventing loosening or fluttering of the hook-and-loop fastener 1. In addition, at this time, curved surfaces that bend downward are formed in front and behind the support surface 23a of the block portion 23, so that the hook-and-loop fastener 1 can be prevented from getting caught on the block portion 23 and being damaged by the block portion 23 during transport.

[0074] In this embodiment, by moving the block portion 23 to the fixed position shown in Fig. 3, the contact roller 22 held in the standby position can be lifted by the block portion 23 via the hook-and-loop fastener 1. At this time, the contact roller 22 is biased downward by an elastic member (not shown) of the sensor portion 20, so that the contact roller 22 can be brought into contact with the upper surface (the other surface) of the hook-and-loop fastener 1 being transported. As a result, the hook-and-loop fastener 1 can be stably sandwiched in the vertical direction by the block portion 23 held in the fixed position and the contact roller 22 biased by the elastic member, as shown in Figs. 3 and 4, for example.

[0075] Furthermore, in this embodiment, a detection section (not shown) provided in the sensor section 20 detects the amount of displacement of the contact roller 22 relative to the support surface 23a of the block section 23. In this case, the detection section uses the position of the support surface 23a of the block section 23 held in a fixed position as a reference (zero position), and can detect the difference (amount of displacement) in the vertical direction between the position of the support surface 23a and the contact position where the contact roller 22 comes into contact with the upper surface of the hook-and-loop fastener 1 as the overall thickness of the hook-and-loop fastener 1.

[0076] Therefore, thickness measurement can be started by moving the block portion 23 to the measurement position as described above. Furthermore, after thickness measurement has started, the hook-and-loop fastener 1 being transported within the thickness measuring device 10 can be supported by the support surface 23a of the block portion 23 at a position between the first guide roller 11 and the second guide roller 12. At the same time, the contact roller 22 can be brought into contact with the upper surface of the hook-and-loop fastener 1 while rotating. This makes it possible to continuously and smoothly measure the overall thickness of the hook-and-loop fastener 1 (i.e., the thickness from the lower surface position of the base portion of the hook-and-loop fastener 1 to the upper end positions of the engaging elements) while continuing to transport the hook-and-loop fastener 1.

[0077] As described above, according to the thickness measuring device 10 and thickness measuring method of this embodiment, the overall thickness of the hook-and-loop fastener 1 can be continuously measured while the hook-and-loop fastener 1 that has undergone the primary molding process and the secondary molding process is being transported. Therefore, even when, for example, a stretching process in which the hook-and-loop fastener 1 is stretched in the machine direction is continuously performed after the secondary molding process to manufacture the hook-and-loop fastener 1, the thickness of the hook-and-loop fastener 1 can be continuously measured between the secondary molding process and the stretching process. This also makes it possible to feed back the measurement results of the thickness of the hook-and-loop fastener 1 to the heat pressing device that performs the secondary molding process, so that the heat pressing device can easily make the thickness of the hook-and-loop fastener 1 obtained after the secondary molding process uniform by controlling the processing conditions based on the measurement results, etc.

[0078] Furthermore, in this embodiment, as described above, when measurement is not being performed, such as before starting thickness measurement, the contact roller 22 and block portion 23 of the sensor portion 20 are held at a position away from the hook-and-loop fastener 1. Therefore, even if a unique portion such as a connecting portion is formed on the hook-and-loop fastener 1, it is possible to prevent the transport of the hook-and-loop fastener 1 from being stopped or the contact roller 22 and block portion 23 from being damaged or broken due to the unique portion.

[0079] The present invention is not limited to the above-described embodiments, and various modifications are possible as long as they have substantially the same configuration as the present invention and provide similar operational effects. For example, in the above-described embodiments, the sheet member 1 to be measured for thickness is a hook-and-loop fastener 1, but in the present invention, the sheet member to be measured is not limited to a hook-and-loop fastener. The thickness measurement device and thickness measurement method of the present invention can measure the thickness of sheet-like members other than hook-and-loop fasteners, as long as the sheet member has a sheet-like support portion and at least one structure integrally provided on one surface of the support portion. Furthermore, the shape, structure, size, etc. of the sheet member are not particularly limited.

[0080] Furthermore, in the above-described embodiment, the sensor unit 20 is provided with one sensor shaft 21 and one contact roller 22, thereby measuring the thickness of the hook-and-loop fastener 1 at one location (the center) in the width direction (orthogonal direction) of the hook-and-loop fastener 1. However, in the present invention, there is no particular limitation on the number of sensor shafts and contact rollers provided. For example, in the present invention, multiple sensor shafts and contact rollers may be provided at different positions in the orthogonal direction. This makes it possible to simultaneously measure the thickness of a sheet material at multiple different positions in the width direction while the sheet material is being transported.

[0081] REFERENCE SIGNS LIST 1 hook-and-loop fastener (sheet member) 10 thickness measuring device 11 first guide roller 12 second guide roller 20 sensor portion 21 sensor shaft portion 21a roller holding portion 22 contact roller 23 block portion 23a support surface 23b front end surface 23c rear end surface 24 cover portion 24a bottom surface portion 24b front vertical wall portion 24c rear vertical wall portion 24d insertion hole portion

Claims

1. A thickness measuring device (10) for measuring the thickness of a sheet member (1) having a structure integrally provided on one surface of a support portion as the sheet member (1) is conveyed, the thickness measuring device (10) comprises a first guide roller (11) that contacts the sheet member (1), a second guide roller (12) that is disposed downstream of the first guide roller (11) and that contacts the sheet member (1), and a sensor unit (20) that is disposed between the first guide roller (11) and the second guide roller (12), the sensor unit (20) comprises a sensor shaft portion (21), a contact roller (22) that is rotatably held at the tip portion of the sensor shaft portion (21), a block portion (23) that supports the sheet member (1), and a detection unit that detects the amount of displacement of the contact roller (22) relative to the block portion (23), the contact roller (22) and the block portion (23) are disposed on opposite sides of the conveying path of the sheet member (1), the block portion (23) is provided so as to be movable in a direction approaching and moving away from the contact roller (22); and, during the measurement of the thickness, the block portion (23) comes into contact with one side of the sheet material (1) being transported, and the contact roller (22) comes into contact with the other side of the sheet material (1) being transported, thereby sandwiching the sheet material (1) being transported between the block portion (23) and the contact roller (22).

2. The thickness measuring device according to claim 1, wherein the block portion (23) is held away from the conveying path of the sheet material (1) when the thickness is not being measured.

3. The first guide roller (11) and the second guide roller (12) are arranged so as to contact the sheet member (1) from the side of the surface on which the structure is formed, and when the direction in which the block portion (23) approaches and moves away from the contact roller (22) is defined as the vertical direction, the block portion (23) is provided so as to be movable in the vertical direction between a first position that is arranged below the respective lower end positions of the first guide roller (11) and the second guide roller (12) and a second position that is arranged above the respective lower end positions, and when the thickness is not being measured, the block portion (23) is held at the first position, and the contact roller (22) is held in a position above and away from the conveying path of the sheet member (1) in a state of not contacting the sheet member (1), 3. The thickness measuring device according to claim 1, wherein, during the thickness measurement, the block portion (23) is held at the second position, thereby contacting the sheet material (1) being transported from below and applying tension to the sheet material (1) between the first guide roller (11) and the second guide roller (12), and the contact roller (22) contacts the sheet material (1) to which the tension has been applied from above.

4. The thickness measuring device according to claim 3, characterized in that the block portion (23) has a support surface (23a) that supports the sheet material (1), and the support surface (23a) of the block portion (23) has a plane perpendicular to the up-down direction.

5. A thickness measuring device as described in any one of claims 1 to 4, characterized in that the contact roller (22) is formed in a cylindrical shape, and when measuring the thickness, the block portion (23) contacts the sheet member (1) from the side opposite to the surface on which the structure is formed, and the contact roller (22) contacts the sheet member (1) from the side on which the structure is formed.

6. A thickness measuring device as described in any one of claims 1 to 5, characterized in that a cover portion (24) for protecting the sensor shaft portion (21) and the contact roller (22) is provided between the first guide roller (11) and the second guide roller (12), the cover portion (24) has a shape in which a cross section when the cover portion (24) is cut along the machine direction in which the sheet material (1) is transported is substantially U-shaped, and a bottom surface portion (24a) of the cover portion (24) has a hole portion (24d) that penetrates from the inner surface to the outer surface of the cover portion (24) and allows the contact roller (22) to be inserted therethrough.

7. A thickness measurement method for measuring the thickness of a sheet member (1) having a support portion on one side of which a structure is integrally provided, using a thickness measurement device (10) while transporting the sheet member (1), the thickness measurement device (10) has a first guide roller (11) that contacts the sheet member (1), a second guide roller (12) that is disposed downstream of the first guide roller (11) and contacts the sheet member (1), and a sensor unit (20) that is disposed between the first guide roller (11) and the second guide roller (12), and the thickness measurement method includes the steps of: when starting to measure the thickness, moving a block portion (23) of the sensor unit (20) to approach a contact roller (22) of the sensor unit (20); the block portion (23) contacts one side of the sheet member (1) being transported and the contact roller (22) contacts the other side of the sheet member (1) to sandwich the sheet member (1) being transported between the block portion (23) and the contact roller (22); and measuring the thickness of the sheet member (1) by detecting an amount of displacement of the contact roller (22) relative to the block portion (23) while the sheet member (1) is sandwiched between the block portion (23) and the contact roller (22).

8. The method for measuring thickness according to claim 7, further comprising: holding said block portion (23) away from a conveying path of said sheet material (1) when said thickness is not being measured.

9. The first guide roller (11) and the second guide roller (12) are arranged so as to contact the sheet member (1) from the side of the surface on which the structure is formed, and when the direction in which the block portion (23) approaches and moves away from the contact roller (22) is defined as the vertical direction, the block portion (23) is provided so as to be movable in the vertical direction between a first position that is arranged below the respective lower end positions of the first guide roller (11) and the second guide roller (12) and a second position that is arranged above the respective lower end positions, and the thickness measuring method comprises: when the thickness is not being measured, holding the block portion (23) at the first position, and holding the contact roller (22) at a position above and away from the conveying path of the sheet member (1) in a non-contact state with the sheet member (1); The thickness measuring method according to claim 7 or 8, characterized in that, during the thickness measurement, the block portion (23) is held at the second position, thereby bringing the block portion (23) into contact with the sheet material (1) being transported from below to apply tension to the sheet material (1) between the first guide roller (11) and the second guide roller (12), and bringing the contact roller (22) into contact with the sheet material (1) to which the tension has been applied from above.

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