JP2010006025A - Filament winding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filament winding apparatus which detects tension applied to a fiber bundle without bending the route of the fiber bundle, is installed easily, and has a tension sensor capable of space saving. <P>SOLUTION: The filament winding apparatus 1 includes the tension sensor 5 for detecting the tension of the traveling fiber bundle 3. The tension sensor 5 includes a tension adjustment part 20 which applies the tension to the traveling fiber bundle 3 and is movable in the traveling direction of the fiber bundle 3, a support part 22 for stopping the movement of the tension adjustment part 20, and a detection part 23 which detects force received by the support part 22 from the tension adjustment part 20 as the value of the tension applied to the fiber bundle 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique of a filament winding apparatus provided with a tension sensor that detects the tension of a fiber bundle.

  2. Description of the Related Art Conventionally, a filament winding apparatus is known in which a liquid bundle such as carbon fiber is impregnated with a liquid resin, wound around a liner or the like that forms the shape of a product, and the resin is heated and cured.

  In such a filament winding apparatus, the fiber bundle is wound around a liner or the like with a predetermined tension applied during filament winding molding. At this time, if the tension applied to the fiber bundle is not sufficient, the fiber bundle is not tightly wound around the liner or the like, and the strength of the filament wound product is insufficient. Therefore, the tension applied to the fiber bundle at the time of filament winding molding needs to be kept constant with sufficient tension for winding around a liner or the like. Therefore, in the filament winding apparatus, a tension sensor that detects the tension applied to the fiber bundle is provided.

  Conventionally, as a tension sensor in a filament winding apparatus, a dancer roller type comprising a pair of fixed rollers and a guide roller provided between the pair of fixed rollers and below the pair of fixed rollers. The thing is known (for example, patent document 1).

The dancer roller type tension sensor measures the tension applied to the fiber bundle by guiding the fiber bundle guided by the fixed roller to the guide roller provided below and measuring the force acting on the guide roller.
JP 2004-209923 A

  In the dancer roller type tension sensor, the tension of the fiber bundle is detected by guiding the fiber bundle to a guide roller provided below by a fixed roller. Therefore, in the dancer roller type tension sensor, since the path of the fiber bundle is bent by the fixed roller, when a large tension is applied to the fiber bundle, the bent part of the fiber bundle is more than necessary. There was a problem that force was applied and the fiber bundle was damaged.

  Also, in the dancer roller type tension sensor, the fiber bundle is guided to the fixed roller and the guide roller to detect the tension, and therefore, the work such as hanging the fiber bundle on the fixed roller and the guide roller is necessary and complicated. There was also a problem.

  Furthermore, since the dancer roller type tension sensor is configured to detect the tension applied to the fiber bundle by a guide roller provided below the fixed roller, there is sufficient space in the vertical direction when the tension sensor is provided. Therefore, there is a problem that it is difficult to downsize the apparatus.

  The present invention has been made to solve such a problem. A tension sensor that detects tension applied to a fiber bundle without bending the fiber bundle path, is easy to install, and can save space. An object is to provide a filament winding apparatus provided.

  The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

A filament winding apparatus according to a first invention is:
A filament winding apparatus provided with a tension sensor for detecting the tension of a traveling fiber bundle,
The tension sensor is
A tension adjusting unit that applies tension to the traveling fiber bundle and is movable in the traveling direction of the fiber bundle;
A support portion for preventing movement of the tension adjusting portion;
A detection unit that detects a force that the support unit receives from the tension adjustment unit as a value of a tension applied to the fiber bundle;
It comprises.

A filament winding apparatus according to a second invention is the filament winding apparatus according to the first invention,
The tension adjusting unit applies tension to the fiber bundle by niping the traveling fiber bundle,
Based on the detection result of the detection unit, the nip force of the tension adjustment unit is adjusted so that the tension becomes a predetermined value.

A filament winding apparatus according to a third invention is the filament winding apparatus according to the first or second invention,
The detection unit is interposed between the tension adjustment unit and the support unit.

  As effects of the present invention, the following effects can be obtained.

  In the first invention, the tension adjusting portion receives an urging force so as to move in the traveling direction of the fiber bundle. The support portion prevents the tension adjusting portion from moving against the biasing force. The force necessary to prevent the movement of the tension adjusting unit is the tension applied to the fiber bundle. The detection unit can detect the tension applied to the traveling fiber bundle by detecting the force received by the support unit from the tension adjustment unit as the value of the tension applied to the fiber bundle. For this reason, a tension sensor for detecting the tension of the fiber bundle can be provided without bending the path of the fiber bundle, and the space for providing the tension sensor can be reduced. Further, since the path of the fiber bundle is not bent, the fiber bundle is not damaged even in the case of high tension.

  In the second invention, the tension adjusting unit applies tension to the fiber bundle by niping the traveling fiber bundle and, based on the detection result of the detecting unit, the tension adjusting unit so that the tension becomes a predetermined value. Since the nip force is adjusted, the tension can be adjusted to a predetermined value while detecting the tension.

  In 3rd invention, since the detection part was interposed between the tension adjustment part and the support part, a detection part can be installed along the running direction of a fiber bundle. For this reason, the space for providing a detection part can be made small, and a tension sensor can be reduced in size.

  Hereinafter, a first example of a filament winding apparatus 1 (hereinafter referred to as FW apparatus 1) according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of the FW device 1 according to the first embodiment.

  The FW device 1 includes a unwinding device 4 for unwinding a carbon fiber bundle 3 (hereinafter referred to as a fiber bundle 3) from a bobbin 2, a tension sensor 5 for detecting a tension applied to the fiber bundle 3, and a fiber A resin impregnation device 7 for injecting and impregnating the bundle 3 with resin and a traverse device 8 for traversing the fiber bundle 3 are provided.

  As shown in FIG. 1, the fiber bundle 3 has a tape shape with a flat surface on the top and bottom, and the fiber bundle 3 is impregnated with resin from the resin impregnation device 7. The FW device 1 winds the fiber bundle 3 impregnated with the resin with the resin impregnation device 7 around the liner 9 while traversing with the traverse device 8.

  The FW device 1 detects the tension applied to the fiber bundle 3 by the tension sensor 5 before the resin impregnation device 7 impregnates the upper surface of the fiber bundle 3 with the predetermined tension. Adjusted to be a value. By detecting and adjusting the tension by the tension sensor 5, the fiber bundle 3 can be tightly wound around the liner 9.

  Next, the tension sensor 5 will be described. As shown in FIG. 1, the tension sensor 5 is provided on the upstream side of the resin impregnation apparatus 7. Note that the installation position of the tension sensor 5 is not limited to the upstream side of the resin impregnation apparatus 7, and in the case where a tension that does not affect the resin impregnated in the fiber bundle 3 is applied to the fiber bundle 3. Alternatively, it may be provided in the vicinity of the liner 9 on the downstream side of the resin impregnation apparatus 7.

  FIG. 2 is a side view of the tension sensor 5 of the FW device 1 according to the first embodiment. As shown in FIG. 2, the tension sensor 5 includes a tension adjustment unit 20, a support unit 22, and a detection unit 23.

  The tension adjusting unit 20 nips the fiber bundle 3 and is movable in the traveling direction of the fiber bundle 3 (arrow 80). The tension adjusting unit 20 includes a main body unit 21, a contact unit 24, a pedestal unit 25, and a drive unit 26. The tension adjusting unit 20 is installed on the fiber bundle 3 at a position where the first end 24a of the contact portion 24 and the pedestal 25 can nip the traveling fiber bundle 3.

  The main body 21 mounts the contact portion 24, the pedestal portion 25, and the drive portion 26. The main body 21 is provided with wheels 28 and 28 as traveling means at the lower portion thereof, and is movable in the traveling direction of the fiber bundle 3 (arrow 80). Note that the travel means of the main body 21 is not limited to the wheels 28, 28. If the main body 21 is travel means that can move in the travel direction of the fiber bundle 3, a rail is provided at the lower part of the main body 21. The rail may be configured such that the main body 21 slides.

  The contact portion 24 is a portion that nips the fiber bundle 3 together with the base portion 25. As shown in FIG. 2, the contact portion 24 is a leaf spring-like member, and the first end portion 24 a, which is one end portion of the contact portion 24, can nip one end portion of the base portion 25 and the fiber bundle 3. A second end portion 24 b which is the other end portion of the contact portion 24 is fixed to the peripheral surface of the drive shaft 27 of the drive portion 26. The pedestal portion 25 is a portion that nips the fiber bundle 3 together with the contact portion 24, and is fixed to the main body portion 21.

  The drive unit 26 has a drive shaft 27. The drive unit 26 rotates to the position where the first end 24a of the contact part 24 and the pedestal part 25 nip the fiber bundle 3 by rotating the drive shaft 27 clockwise (as shown in FIG. 2) by a predetermined angle. Moving. On the other hand, the drive unit 26 moves in a direction in which the first end portion 24a of the contact portion 24 is separated from the fiber bundle 3 by rotating the drive shaft 27 by a predetermined angle counterclockwise in the drawing.

  The support part 22 prevents the tension adjusting part 20 from moving. The support portion 22 is provided on the machine base frame 29 of the FW device 1. The support unit 22 is provided on the front side with respect to the movement direction (arrow 81) of the tension adjusting unit 20, and receives the force pressed by the tension adjusting unit 20 via the detection unit 23.

  The detection unit 23 detects the force received from the tension adjustment unit 20 (the force by which the tension adjustment unit 20 presses the support unit 22) as the value of the tension applied to the fiber bundle 3. The detection unit 23 includes a load cell 23 a as detection means, and detects the force received from the tension adjustment unit 20. In addition, the detection means of the detection part 23 is not limited to the load cell 23a, What is necessary is just the structure which can detect the force received from the tension adjustment part 20. FIG. One end of the load cell 23 a is connected to the front side in the movement direction of the tension adjusting unit 20, and is interposed between the tension adjusting unit 20 and the support unit 22. Note that the load cell 23 a may have one end connected to the support portion 22.

  The force received from the tension adjusting unit 20 detected by the load cell 23a is sent to the control unit 85 described later as a detection signal. Based on the detection signal, the control unit 85 converts the force received from the tension adjusting unit 20 into a tension value applied to the fiber bundle 3. Thus, the detecting unit 23 converts the force received from the tension adjusting unit 20 detected by the load cell 23a into the value of the tension applied to the fiber bundle 3 by the control unit 85, thereby providing the tension applied to the fiber bundle 3. The value of is detected.

  Next, the mechanism of the tension sensor 5 will be described. As shown in FIG. 2, the fiber bundle 3 travels in the right direction (arrow 80) in the figure. Further, the tension adjusting unit 20 nips the fiber bundle 3 by the first end portion 24a of the contact portion 24 and the pedestal portion 25 to such an extent that the fiber bundle 3 can travel. Thereby, the tension adjusting unit 20 receives a biasing force while being pulled by the fiber bundle 3, and moves in the right direction (arrow 81) in the figure.

  When the tension adjustment unit 20 moves to the right in the figure, the tension adjustment unit 20 presses the support unit 22 via the load cell 23a of the detection unit 23. On the other hand, the support part 22 prevents the movement of the tension adjusting part 20 via the load cell 23a. When the movement of the tension adjusting unit 20 is blocked by the support unit 22, only the fiber bundle 3 runs in the right direction in the figure. At this time, since the fiber bundle 3 is nipped by the contact portion 24 and the pedestal portion 25 of the tension adjusting portion 20 that is prevented from moving by the support portion 22, the fiber bundle 3 is pulled by the tension adjusting portion 20 and has a constant tension. Is granted. In addition, when the nip of the fiber bundle 3 by the contact portion 24 and the pedestal portion 25 is released, the fiber bundle 3 is not pulled by the tension adjusting unit 20, so that no tension is applied.

  Next, the system of the tension sensor 5 will be described. 3 is a system diagram of the tension sensor 5 of the FW device 1 according to the first embodiment, and FIG. 4 is a diagram when adjusting the tension applied to the fiber bundle 3 by the tension sensor 5 of the FW device 1 according to the first embodiment. It is a flowchart of. As shown in FIG. 3, the drive unit 26 of the tension adjustment unit 20 and the load cell 23 a of the detection unit 23 are connected to the control unit 85, and the drive unit 26 and the load cell 23 a are controlled by the control unit 85. Yes. When the tension adjusting unit 20 moves and presses the support unit 22, the load cell 23 a transmits the force pressed from the tension adjusting unit 20 to the control unit 85 as a detection signal. When receiving the detection signal, the controller 85 detects the tension applied to the fiber bundle 3 based on a preset program. Here, the preset program is a program for calculating the tension applied to the fiber bundle 3 from the force with which the load cell 23a of the detector 23 is pressed. In addition, the tension | tensile_strength provided to the fiber bundle 3 respond | corresponds with the force with which the load cell 23a of the detection part 23 is pressed by the tension adjustment part 20, and a fiber is so strong that the load cell 23a is pressed by the tension adjustment part 20 becomes large. The tension applied to the bundle 3 is increased.

  As shown in FIG. 4, the control unit 85 rotates the drive shaft 27 clockwise (FIG. 2) with respect to the drive unit 26 (in a direction in which the winding of the second end 24 b of the contact unit 24 is strengthened) by a predetermined angle. By transmitting a control signal indicating that the actuator is only rotated, the drive unit 26 rotates the drive shaft 27 clockwise (FIG. 2) by a predetermined angle (in a direction in which the winding of the second end 24b of the contact unit 24 is strengthened). It is driven to rotate only (S1). When the drive unit 26 drives the drive shaft 27, the load cell 23a detects a force pressed from the tension adjusting unit 20 (S2), and transmits a detection signal to the control unit 85. When receiving the detection signal, the controller 85 detects the tension applied to the fiber bundle 3 based on the program (S3).

  When detecting the tension applied to the fiber bundle 3, the control unit 85 determines whether the tension is a predetermined tension (S4). When the control unit 85 determines that the tension is a predetermined tension (S4-Yes), the control unit 85 holds the control of the tension sensor 5 (S5), and controls the fiber bundle 3 based on the detection signal transmitted from the load cell 23a. The detection of the applied tension is repeated (S2 to S4).

  If the controller 85 determines that the tension is not the predetermined tension (S4-No), it determines whether the tension is greater than the predetermined tension (S6). When the control unit 85 determines that the tension is greater than the predetermined tension (S6-Yes), the drive shaft 27 is rotated counterclockwise (FIG. 2) with respect to the drive unit 26 (second end of the contact unit 24). A control signal is transmitted to the effect that it rotates by a predetermined angle (in the direction of loosening the winding of 24b). Upon receiving the control signal, the drive unit 26 drives the drive shaft 27 to rotate by a predetermined angle counterclockwise (in the direction of loosening the winding of the second end 24b of the contact portion 24) (S7). . When the drive unit 26 drives the drive shaft 27, the load cell 23a detects a force pressed from the tension adjusting unit 20 (S2), and transmits a detection signal to the control unit 85. When receiving the detection signal, the control unit 85 detects again the tension applied to the fiber bundle 3 based on the program (S3).

  When the control unit 85 determines that the tension is smaller than the predetermined tension (S6-No), the drive shaft 27 is rotated clockwise (FIG. 2) with respect to the drive unit 26 (second end 24b of the contact unit 24). A control signal is transmitted to the effect of turning by a predetermined angle (in the direction of increasing the winding). When receiving the control signal, the drive unit 26 drives the drive shaft 27 to rotate by a predetermined angle in the clockwise direction (FIG. 2) (in a direction in which the winding of the second end 24b of the contact unit 24 is strengthened). (S1). When the drive unit 26 drives the drive shaft 27, the load cell 23a detects a force pressed from the tension adjusting unit 20 (S2), and transmits a detection signal to the control unit 85. When receiving the detection signal, the control unit 85 detects again the tension applied to the fiber bundle 3 based on the program (S3).

  Thus, the control unit 85 detects the tension applied to the fiber bundle 3 based on the force with which the load cell 23a is pressed by the tension adjusting unit 20, and controls the tension adjusting unit 20 based on the detected tension. The nip force of the tension adjusting unit 20 is adjusted to adjust the tension applied to the fiber bundle 3.

  Next, a second embodiment of the FW device 1 according to the present invention will be described. The configuration other than the tension sensor 5 of the FW device 1 according to the second embodiment is the same as the configuration of the FW device 1 according to the first embodiment, and a description thereof will be omitted.

  FIG. 5 is a side view of the tension sensor 5 of the FW device 1 according to the second embodiment. As shown in FIG. 5, the tension sensor 5 includes a tension adjustment unit 20, a support unit 22, and a detection unit 23. Here, since the configuration of the tension adjusting unit 20 is the same as the configuration of the FW device 1 according to the first embodiment, the description thereof is omitted.

  The support part 22 prevents the tension adjusting part 20 from moving. The support portion 22 is provided on the machine base frame 29 of the FW device 1. The support unit 22 is provided on the rear side with respect to the movement direction (arrow 81) of the tension adjusting unit 20, and holds the force that the tension adjusting unit 20 pulls through the load cell 23a of the detecting unit 23.

  The detection unit 23 detects the force received from the tension adjustment unit 20 (the force by which the tension adjustment unit 20 pulls the support unit 22) as the value of the tension applied to the fiber bundle 3. The detection unit 23 includes a load cell 23 a as detection means, and detects the force received from the tension adjustment unit 20. In addition, the detection means of the detection part 23 is not limited to the load cell 23a, What is necessary is just the structure which can detect the force received from the tension adjustment part 20. FIG. One end of the load cell 23 a is connected to the rear side of the main body 21 in the transport direction, and the other end is connected to the support 22, so that the load cell 23 a is interposed between the tension adjusting unit 20 and the support 22. .

  Next, the mechanism of the tension sensor 5 of the FW device 1 according to the second embodiment will be described. As shown in FIG. 5, the fiber bundle 3 travels in the right direction (arrow 80) in the figure. Further, the tension sensor 5 nips the fiber bundle 3 by the first end portion 24a of the contact portion 24 and the pedestal portion 25 to such an extent that the fiber bundle 3 can travel. Thereby, the tension adjusting unit 20 receives a biasing force while being pulled by the fiber bundle 3, and moves in the right direction (arrow 81) in the figure.

  When the tension adjusting unit 20 moves to the right in the figure, the tension adjusting unit 20 pulls the support unit 22 via the load cell 23a of the detection unit 23. At this time, the load cell 23a is extended. On the other hand, the support part 22 prevents the movement of the tension adjusting part 20 via the load cell 23a. When the movement of the tension adjusting unit 20 is blocked by the support unit 22, only the fiber bundle 3 runs in the right direction in the figure. At this time, since the fiber bundle 3 is nipped by the contact portion 24 and the pedestal portion 25 of the tension adjusting portion 20 that is prevented from moving by the support portion 22, the fiber bundle 3 is pulled by the tension adjusting portion 20 and has a constant tension. Is granted. In addition, when the nip of the fiber bundle 3 by the contact portion 24 and the pedestal portion 25 is released, the fiber bundle 3 is not pulled by the tension adjusting unit 20, so that no tension is applied.

  The tension applied to the fiber bundle 3 corresponds to the force by which the load cell 23a is pulled by the tension adjusting unit 20, and the tension applied to the fiber bundle 3 increases as the force by which the load cell 23a is pulled by the tension adjusting unit 20 increases. growing. As in the case of the tension sensor 5 of the FW device 1 according to the first embodiment, the tension sensor 5 of the FW device 1 according to the second embodiment is based on the force with which the load cell 23a is pulled by the tension adjusting unit 20. The tension applied to 3 is detected.

  Next, a third embodiment of the FW device 1 according to the present invention will be described. The configuration other than the tension sensor 5 of the FW device 1 according to the third embodiment is the same as the configuration of the FW device 1 according to the first embodiment, and a description thereof will be omitted.

  FIG. 6 is a side view of the tension sensor 5 of the FW device 1 according to the third embodiment. As shown in FIG. 6, the tension sensor 5 includes a tension adjustment unit 20, a support unit 22, and a detection unit 23. Here, since the structure of the support part 22 and the detection part 23 is the same as the said structure of the FW apparatus 1 which concerns on 1st Example, description is abbreviate | omitted.

  The tension adjusting unit 20 nips the fiber bundle 3 and is movable in the traveling direction of the fiber bundle 3 (arrow 80). The tension adjusting unit 20 includes a main body unit 21, a contact unit 31, a pedestal unit 25, and a drive unit 33. In addition, since the structure of the main-body part 21 and the base part 25 is the same as the said structure of the FW apparatus 1 which concerns on 1st Example, description is abbreviate | omitted.

  As shown in FIG. 6, the contact part 31 is a substantially plate-like member, and the entire contact surface 31a of the contact part 31 and the pedestal part 25 are provided so that the traveling fiber bundle 3 can be nipped. . The drive unit 33 is an air cylinder, and drives the rod 34 up and down by taking in and out compressed air. The drive unit 33 is not limited to an air cylinder, and any mechanism that can drive the rod 34 up and down may be used. The rod 34 is connected to the contact portion 31. When the rod 34 moves downward, the contact surface 31a of the contact portion 31 and the base portion 25 move to a position where the fiber bundle 3 can be nipped. On the other hand, when the rod 34 moves upward, the contact surface 31 a of the contact portion 31 moves in a direction away from the fiber bundle 3.

  The tension sensor 5 in the FW device 1 according to the third embodiment is limited to the case where the support portion 22 and the detection portion 23 are provided on the front side of the tension adjustment portion 20 (FW device 1 according to the first embodiment). The support unit 22 and the detection unit 23 may be provided on the rear side of the tension adjustment unit 20 (FW device 1 according to the second embodiment).

  As described above, the FW device 1 according to the present invention receives a biasing force so that the tension adjusting unit 20 moves in the traveling direction of the fiber bundle 3 (arrow 80). The support part 22 blocks the movement of the tension adjusting part 20 against the biasing force. The force necessary to prevent the movement of the tension adjusting unit 20 is the tension applied to the fiber bundle 3. The detection unit 23 can detect the tension applied to the traveling fiber bundle 3 by detecting the force received by the support unit 22 from the tension adjustment unit 20 as the value of the tension applied to the fiber bundle 3. For this reason, the tension sensor 5 for detecting the tension of the fiber bundle 3 can be provided without bending the path of the fiber bundle 3, and the space for providing the tension sensor 5 can be reduced. Further, since the path of the fiber bundle 3 is not bent, the fiber bundle 3 is not damaged even in the case of high tension.

  Further, in the FW device 1 according to the present invention, the tension adjusting unit 20 applies tension to the fiber bundle 3 by nipping the traveling fiber bundle 3, and the tension is predetermined based on the detection result of the detection unit 23. Since the nip force of the tension adjusting unit 20 is adjusted so as to be a value, the tension can be adjusted to a predetermined value while detecting the tension.

  Furthermore, since the FW device 1 according to the present invention has the load cell 23a of the detection unit 23 interposed between the tension adjustment unit 20 and the support unit 22, the detection unit 23 is moved along the traveling direction (arrow 80) of the fiber bundle 3. Can be installed. For this reason, the space for providing the detection part 23 can be made small, and the tension sensor 5 can be reduced in size.

The perspective view of FW device 1 concerning the 1st example. The side view of the tension sensor 5 of the FW device 1 according to the first embodiment. The system diagram of the tension sensor 5 of the FW device 1 according to the first embodiment. The flowchart at the time of adjusting the tension | tensile_strength which the tension sensor 5 of the FW apparatus 1 which concerns on 1st Example provides to the fiber bundle 3. FIG. The side view of the tension sensor 5 of the FW apparatus 1 which concerns on 2nd Example. A side view of tension sensor 5 of FW device 1 concerning a 3rd example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 FW apparatus 3 Fiber bundle 5 Tension sensor 20 Tension adjustment part 22 Support part 23 Detection part 23a Load cell (detection part)
85 Control unit

Claims (3)

A filament winding apparatus provided with a tension sensor for detecting the tension of a traveling fiber bundle,
The tension sensor is
A tension adjusting unit that applies tension to the traveling fiber bundle and is movable in the traveling direction of the fiber bundle;
A support portion for preventing movement of the tension adjusting portion;
A detection unit that detects a force that the support unit receives from the tension adjustment unit as a value of a tension applied to the fiber bundle;
A filament winding apparatus comprising: The tension adjusting unit applies tension to the fiber bundle by niping the traveling fiber bundle,
The filament winding apparatus according to claim 1, wherein a nip force of the tension adjusting unit is adjusted based on a detection result of the detecting unit so that the tension becomes a predetermined value.   The filament winding apparatus according to claim 1, wherein the detection unit is interposed between the tension adjustment unit and the support unit.

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