Tension balancer

Abstract

This tension balancer comprises: first to n-th cylindrical members; first to (n-1)-th coil springs; a rear hook attached to the first cylindrical member; a front hook attached to the n-th cylindrical member; first to (n-1)-th front spring washers that each include a plurality of grooves; first to (n-1)-th rear spring washers; and a plurality of fixtures that are detachably fixed to the plurality of grooves on a one-to-one manner. Each of the plurality of fixtures is in contact with a groove, among the plurality of grooves of an m-th front spring washer, that corresponds in a one-to-one manner, and with an (m+1)-th cylindrical member, and restricts movement of the (m+1)-th cylindrical member in a direction parallel to a coil axis.

Description

Tension balancer 【0001】 One embodiment of the present invention relates to a tension balancer that can be used for overhead lines. 【0002】 In recent years, tension balancers are attached to overhead lines such as railways. For example, Patent Documents 1 to 6 disclose a spring-type tension balancer having a plurality of cylindrical members arranged coaxially and a coil spring arranged between the cylindrical members as a basic configuration. The first end of the spring-type tension balancer is fixed to a support column, and the second end on the opposite side of the first end is connected to an overhead line. The coil spring is built into the tension balancer in a compressed state. By utilizing the elastic force of the coil spring trying to return to its original length, the spring-type tension balancer can pull the overhead line with an appropriate tension. Also, even if expansion and contraction due to temperature changes occur in the spring-type tension balancer, the spring-type tension balancer can always maintain the overhead line almost horizontally. 【0003】 Japanese Patent Application Laid-Open No. 2023-117748, Japanese Patent Application Laid-Open No. 2021-133822, Japanese Patent Application Laid-Open No. 2020-131730, Japanese Patent Application Laid-Open No. 2010-155577, Japanese Patent Application Laid-Open No. 2008-114850, Japanese Patent Application Laid-Open No. 2004-042780 【0004】 One of the problems of one embodiment of the present invention is to provide a tension balancer having a novel structure. Also, one of the problems of one embodiment of the present invention is to provide a spring-type tension balancer capable of suppressing the load when fixing the tension balancer to a support column. 【0005】A tension balancer according to one embodiment of the present invention comprises first to n cylindrical members, first to (n-1) coil springs, a rear hook attached to the first cylindrical member, a front hook attached to the nth cylindrical member, first to (n-1) front spring washers including a plurality of grooves, first to (n-1) rear spring washers, and a plurality of fasteners that are detachably fixed one-to-one in the plurality of grooves, wherein the first to n cylindrical members are arranged such that the (m+1) cylindrical member selected from the first to n cylindrical members is located inside the m cylindrical member selected from the first to n cylindrical members, and the first to (n-1) coil springs are arranged such that the m coil spring selected from the first to (n-1) coil springs is sandwiched between the m cylindrical member and the (m+1) cylindrical member, and the first to (n- 1) The front spring washer and the first to (n-1) rear spring washers are arranged such that the m front spring washer selected from the first to (n-1) front spring washers and the m rear spring washer selected from the first to (n-1) rear spring washers surround the (m+1) cylindrical member, and sandwich the m coil spring in a direction parallel to the coil axis of the m coil spring, and the first to (n-1) front spring washers Each of the plurality of fasteners is fixed to the first to (n-1) cylindrical members and surrounds the first to (n-1) cylindrical members, and each of the plurality of fasteners is in contact with the grooves of the plurality of grooves of the front spring washer m, which correspond one to one, and with the (m+1) cylindrical member, and restricts the movement of the (m+1) cylindrical member in the direction, where n is a natural number between 2 and 5, and m is a natural number between 1 and (n-1). 【0006】This is a perspective view showing a tension balancer according to one embodiment of the present invention. This is an end view showing the end cross-sectional structure of a tension balancer according to one embodiment of the present invention. This is a front view showing a tension balancer according to one embodiment of the present invention. This is a plan view showing a front spring washer according to one embodiment of the present invention. This is a plan view showing a front spring washer according to one embodiment of the present invention. This is an end view showing the end cross-sectional structure of a tension balancer according to one embodiment of the present invention. This is a side view and a rear view showing an example of the structure of a fastener when viewed from the side and when viewed from the rear according to one embodiment of the present invention. This is a side view and a rear view showing an example of the structure of a fastener when viewed from the side and when viewed from the rear according to one embodiment of the present invention. This is an end view showing the end cross-sectional structure of a tension balancer according to one embodiment of the present invention. 【0007】 Hereinafter, embodiments of the invention disclosed in this application will be described with reference to the drawings. However, the present invention can be implemented in various forms without departing from its spirit, and is not construed to be limited to the embodiments described below. 【0008】 While drawings may schematically represent the width, thickness, shape, etc., of each part compared to the actual embodiment in order to clarify the explanation, these are merely examples and do not limit the interpretation of the present invention. Furthermore, in this specification and each drawing, elements having the same function as those described in previously shown drawings are denoted by the same reference numerals, and redundant explanations may be omitted. 【0009】 In this specification and claims, the expression "a structure is exposed from another structure" means a part of a structure that is not covered by another structure, and this part that is not covered by another structure may be covered by yet another structure. Furthermore, the expression also includes a configuration in which a structure is not in contact with another structure. 【0010】[1. Overall Structure] The overall structure of the tension balancer 100 will be described with reference to Figures 1, 2, or 6. Figure 1 is a perspective view showing the overall structure of the tension balancer 100. Figures 2 and 6 are end views showing an example of the end cross-sectional structure obtained by cutting the tension balancer 100 along the dashed line A1-A2 extending in the first direction D1 shown in Figure 1. For example, in the tension balancer 100 shown in Figure 6, the second cylindrical member 130 is pulled out from the first cylindrical member 120, and the first coil spring 128 is compressed, with the fixing device 126 provided in the groove 123 of the first front spring washer 122 so as to maintain the elastic force (restoring force) that causes the first coil spring 128 to return to its original length. Furthermore, the tension balancer 100 shown in Figure 6 has the third cylindrical member 140 pulled out from the second cylindrical member 130, and the second coil spring 138 compressed, with the fixing device 126 driven into the groove 133 of the second front spring washer 132 so as to maintain the elastic force (restoring force) that causes the second coil spring 138 to return to its original length. 【0011】 A tension balancer 100 according to one embodiment of the present invention can be used to pull an overhead line with appropriate tension. 【0012】 In the following, the longitudinal direction of the tension balancer 100 is defined as the first direction D1, and the vertical direction when the tension balancer 100 is installed so that the first direction D1 is horizontal is defined as the third direction D3. The direction perpendicular to the first direction D1 and the third direction D3 is defined as the second direction D2. The first direction D1 is parallel to the central axis of the tension balancer 100 and each cylindrical member, and is the direction in which the second to nth cylindrical members slide (move). Furthermore, the side on which the front hook 150 connected to the overhead line and the rear hook 110 connected to the support column are provided are defined as the front and rear of the tension balancer 100, respectively. 【0013】The tension balancer 100 includes a first cylindrical member 120, a second cylindrical member 130, a third cylindrical member 140, a first coil spring 128, a second coil spring 138, a rear hook 110, a front hook 150, a first front spring washer 122 including a plurality of grooves 123 (see Figures 3 and 4), a second front spring washer 132 including a plurality of grooves 133 (see Figures 3 and 5), a first rear spring washer 134, a second rear spring washer 144, and a plurality of fasteners 126. The tension balancer 100 also includes a support plate 102, a first back plate 104, a U-shaped rod 106, a second back plate 148, and a guide plate 152. 【0014】 The tension balancer 100 shown in Figure 1 is a two-stage tension balancer that includes three cylindrical members arranged coaxially and having different outer diameters. The three cylindrical members are the first cylindrical member 120, the second cylindrical member 130, and the third cylindrical member 140. In the first cylindrical member 120, the second cylindrical member 130, and the third cylindrical member 140, the third cylindrical member 140, selected from the first cylindrical member 120, the second cylindrical member 130, and the third cylindrical member 140, is positioned inside the second cylindrical member 130, selected from the first cylindrical member 120, the second cylindrical member 130, and the third cylindrical member 140, and the second cylindrical member 130, selected from the first cylindrical member 120, the second cylindrical member 130, and the third cylindrical member 140, is positioned inside the first cylindrical member 120, selected from the first cylindrical member 120, the second cylindrical member 130, and the third cylindrical member 140. 【0015】 Furthermore, the coil spring is positioned between adjacent cylindrical members so as to be sandwiched between them. For example, in the case of a first coil spring and a second coil spring, the first coil spring 128, selected from the first coil spring 128 and the second coil spring 138, is positioned so as to be sandwiched between the first cylindrical member 120 and the second cylindrical member 130, and the second coil spring 138, selected from the first coil spring 128 and the second coil spring 138, is positioned so as to be sandwiched between the second cylindrical member 130 and the third cylindrical member 140. 【0016】A rear hook 110 is directly or indirectly attached to one end of the first cylindrical member 120 having the largest outer diameter. A front hook 150 is directly or indirectly attached to one end of the cylindrical member having the smallest outer diameter (the third cylindrical member 140 in the tension balancer shown in Figure 1). In addition, as an optional configuration, a support plate 102 for suspending the tension balancer 100 from an overhead line may be provided on the upper part of the first cylindrical member 120 along the third direction D3. 【0017】 In the first front spring washer 122, the second front spring washer 132, the first rear spring washer 134, and the second rear spring washer 144, the first front spring washer 122, selected from the first front spring washer 122 and the second front spring washer 132, and the first rear spring washer 134, selected from the first rear spring washer 134 and the second rear spring washer 144, surround the second cylindrical member 130 and are arranged to sandwich the first coil spring 128 along a direction parallel to the coil axis of the first coil spring 128 (first direction D1). Furthermore, the second front spring washer 132, selected from the first front spring washer 122 and the second front spring washer 132, and the second rear spring washer 144, selected from the first rear spring washer 134 and the second rear spring washer 144, surround the third cylindrical member 140 and are arranged to sandwich the second coil spring 138 along a direction parallel to the coil axis of the second coil spring 138 (first direction D1). 【0018】 The first front spring washer 122 is sandwiched between the first cylindrical member 120 and the second cylindrical member 130, contacts and is fixed to the front of the inner circumferential surface of the first cylindrical member 120 (the surface on the side of the second cylindrical member 130 along the third direction D3), and is provided in front of the first cylindrical member 120. The second front spring washer 132 is sandwiched between the second cylindrical member 130 and the third cylindrical member 140, contacts and is fixed to the front of the inner circumferential surface of the second cylindrical member 130 (the surface on the side of the third cylindrical member 140 along the third direction D3), and is provided in front of the second cylindrical member 130. 【0019】Each of the multiple fasteners 126 contacts the second cylindrical member 130 with a one-to-one corresponding groove among the multiple grooves 123 (see Figure 4) of the first front spring washer 122, and restricts the movement of the second cylindrical member 130 in the first direction D1. In addition, each of the other multiple fasteners 126 contacts the third cylindrical member 140 with a one-to-one corresponding groove among the multiple grooves 133 (see Figure 5) of the second front spring washer 132, and restricts the movement of the third cylindrical member 140 in the first direction D1. 【0020】 Generalizing the tension balancer 100, it comprises first to nth cylindrical members, first to (n-1)th coil springs, a rear hook 110 attached to the first cylindrical member, a front hook 150 attached to the nth cylindrical member, first to (n-1)th front spring washers each containing a plurality of grooves, first to (n-1)th rear spring washers, and a plurality of fasteners that are detachably fixed one-to-one in the plurality of grooves. The first to nth cylindrical members are arranged such that the (m+1)th cylindrical member selected from the first to nth cylindrical members is located inside the mth cylindrical member selected from the first to nth cylindrical members. In the first to (n-1)th coil springs, the mth coil spring selected from the first to (n-1)th coil springs is arranged so that it is sandwiched between the mth cylindrical member and the (m+1)th cylindrical member. Furthermore, in the first to (n-1) front spring washers and the first to (n-1) rear spring washers, the m-th front spring washer selected from the first to (n-1) front spring washers and the m-th rear spring washer selected from the first to (n-1) rear spring washers surround the (m+1) cylindrical member, and are arranged to sandwich the m-th coil spring in a direction parallel to the coil axis of the m-th coil spring (first direction D1). In addition, each of the first to (n-1) front spring washers is fixed to the first to (n-1) cylindrical members and surrounds the second to nth cylindrical members. Furthermore, each of the multiple fasteners is in contact with the groove of the m-th front spring washer and the (m+1) cylindrical member in a one-to-one correspondence, and restricts the movement of the (m+1) cylindrical member in the first direction D1. For example, the numerical value n is a natural number between 2 and 5 (inclusive), and the numerical value m is a natural number between 1 and (n-1) (inclusive). 【0021】 As shown in Figure 6, in one embodiment of the present invention, a tension balancer 100 can fix the second cylindrical member 130, which is drawn out from the first cylindrical member 120, by driving a relatively simple fastener 126 into the groove 123 of the first front spring washer 122, while the first coil spring 128 is compressed, so as to maintain the elastic force (restoring force) that causes the first coil spring 128 to return to its original length. In addition, another fastener 126 can be driven into the groove 133 of the second front spring washer 132, so as to maintain the elastic force (restoring force) that causes the second coil spring 138 to return to its original length, while the second coil spring 138 is compressed, so as to fix the third cylindrical member 140, which is drawn out from the second cylindrical member 130. When the second cylindrical member 130 is stretched, an elastic force continues to act on the second cylindrical member 130, but the fastener 126 is in contact with the groove 123 and the second cylindrical member 130, and a frictional force acts on the contact surface where the fastener 126 contacts the groove 123 and the second cylindrical member 130. Similarly to the second cylindrical member 130, when the third cylindrical member 140 is stretched, an elastic force continues to act on the third cylindrical member 140, but another fastener 126 is in contact with the groove 133 and the third cylindrical member 140, and a frictional force acts on the contact surface where the other fastener 126 contacts the groove 133 and the third cylindrical member 140. As a result, a force similar to the elastic force acting on the second cylindrical member 130 acts on the fastener 126, causing the fastener 126 to catch on the first front spring washer 122, preventing the fastener 126 from coming off, and firmly fixing the fastener 126 to the second cylindrical member 130. Similarly to the second cylindrical member 130, a force similar to the elastic force acting on the third cylindrical member 140 acts on the other fasteners 126, causing the other fasteners 126 to catch on the second front spring washer 132, preventing the other fasteners 126 from coming off, and firmly fixing the other fasteners 126 to the third cylindrical member 140. 【0022】For example, when a worker installs a tension balancer on an overhead wire, it is necessary to pull out the cylindrical member, but pulling out the cylindrical member at the construction site (high place) requires time and effort. On the other hand, the tension balancer 100 according to one embodiment of the present invention has a configuration that allows the cylindrical member to be fixed in the pulled-out state using an easily detachable fixing device 126, and the worker can install the tension balancer 100, which has been shipped in that state, on the overhead wire. As a result, the worker can omit the work of pulling out the cylindrical member of the tension balancer 100, and therefore the worker can reduce the load when installing the tension balancer on the overhead wire by using the tension balancer 100. 【0023】 Furthermore, the fixing device 126, which can fix the cylindrical member in the extended position, is smaller than the fittings used when installing the tension balancer on an overhead line (for example, fittings called extension fittings), has fewer types of components, and is lightweight. Therefore, the tension balancer 100 according to one embodiment of the present invention has a configuration that can suppress the cost required for manufacturing, is lightweight, and allows for a compact overall size when installed on an overhead line. 【0024】 The tension balancer 100 shown in Figures 1, 2, and 6 is, as an example, a two-stage tension balancer with a numerical value n of 3. The following explanation will continue using the two-stage tension balancer 100. 【0025】 [2. Cylindrical Members] The configuration of the cylindrical members included in the tension balancer 100 will be described with reference to Figure 1, Figure 2, or Figure 6. When describing the cylindrical members of the tension balancer 100, configurations identical or similar to those in Figures 1, 2, and 6 will be described as necessary, and descriptions of such identical or similar configurations may be omitted. 【0026】For example, the outer diameter of the cylindrical members decreases in the order from the first cylindrical member 120 to the third cylindrical member 140. Also, a portion of a cylindrical member having a smaller outer diameter is inserted into a cylindrical member with a larger outer diameter. That is, the third cylindrical member 140 is inserted inside the second cylindrical member 130, and the second cylindrical member 130 is inserted inside the first cylindrical member 120. Although not shown in the illustration, the first cylindrical member 120 may be provided with an opening for draining water that has entered the interior. 【0027】 Furthermore, a first back plate 104 is provided at one rear end of the first cylindrical member 120. The first back plate 104 forms the bottom surface of the first cylindrical member 120. 【0028】 The rear hook 110 is attached to the first back plate 104. For example, the rear hook 110 may be attached to the first back plate 104 by welding or by bolting. Alternatively, the rear hook 110 may be fixed to the first cylindrical member 120 without going through the first back plate 104. 【0029】 A U-shaped rod 106 and a collar 108 are provided at one rear end of the first cylindrical member 120. The U-shaped rod 106 and collar 108 cooperate with the first back plate 104 to form a fall prevention mechanism that prevents the second cylindrical member 130 and the third cylindrical member 140 from falling off. There are no restrictions on the structure of the fall prevention mechanism. As shown in Figure 1, the pair of legs of the U-shaped rod 106 extend in a direction perpendicular to the third direction D3 and pass through the first cylindrical member 120. The collar 108 is provided at the ends of the pair of legs of the U-shaped rod 106. The collar 108 prevents the U-shaped rod 106 from falling off. The first coil spring 128 provided between the first cylindrical member 120 and the second cylindrical member 130, and the second coil spring 138 provided between the second cylindrical member 130 and the third cylindrical member 140, are both positioned in a compressed state. Therefore, the elastic force that tries to return them to their original length pushes the second cylindrical member 130 and the third cylindrical member 140 backwards. However, this movement is restricted by the U-shaped rod 106 and the first back plate 104, preventing the second cylindrical member 130 and the third cylindrical member 140 from falling off. 【0030】 [3. Front Spring Washers] The configuration of the first front spring washer 122 and the configuration of the second front spring washer 132 will be explained with reference to Figures 2 to 6. Figure 3 is a front view of the tension balancer 100 as seen from the front. Figure 4 is a plan view showing the first front spring washer 122. Figure 5 is a plan view showing the second front spring washer 132. Note that in the front view of the tension balancer 100 shown in Figure 3, the illustration of components other than the first cylindrical member 120, the first front spring washer 122, the second cylindrical member 130, the second front spring washer 132, the third cylindrical member 140 and the front hook 150 has been omitted in order to make the front view of the tension balancer 100 easier to see. In describing the front spring washer of the tension balancer 100, configurations identical or similar to those in Figures 1, 2, and 6 will be described as necessary, and descriptions of such identical or similar configurations may be omitted. 【0031】 A ring-shaped first front spring washer 122 surrounding the second cylindrical member 130 is provided in front of the tension balancer 100 (on the front hook 150 side). The first front spring washer 122 is fixed to the front of the inner circumferential surface of the first cylindrical member 120 by a connecting member 124. In other words, the first front spring washer 122 is fixed to the first cylindrical member 120 by the connecting member 124. 【0032】 Furthermore, the first front spring washer 122 surrounds the second cylindrical member 130 but is separated from it. As a result, the first front spring washer 122 blocks a portion of the first cylindrical member 120, and the opening in the first cylindrical member 120 that is not blocked by the first front spring washer 122 acts as an opening for the second cylindrical member 130 to slide inside the first cylindrical member 120, with a portion of it being exposed from the first cylindrical member 120. 【0033】Furthermore, as explained in "1. Overall Structure," the first front spring washer 122 includes a plurality of grooves 123, and a plurality of fasteners 126 are detachably fixed to each of the plurality of grooves 123 in a one-to-one manner. As shown in Figures 3 and 4, the number of plurality of grooves 123 is four as an example. There is no limit to the number of plurality of grooves 123, and the number of plurality of grooves 123 is generally k, where the numerical value k is a natural number. The number of plurality of grooves 123 may be set as appropriate depending on the application or specifications of the tension balancer 100. In addition, the first front spring washer 122 includes a drain hole 125. The drain hole 125 is an opening for draining water that has entered the interior of the tension balancer 100. 【0034】 For example, as shown in Figure 4, if the ring-shaped first front spring washer 122 is considered as a circle with diameter DM1, the drain hole 125 is located on a virtual axis 172 parallel to the third direction D3, passing through the center 170 of the circle, and each of the multiple grooves 123 is located at a position obtained by rotating the drain hole 125 clockwise by α + a × 90 degrees with respect to the center 170. The numerical value a is an integer greater than or equal to 0. 【0035】 The drain hole 125 is provided in the first front spring washer 122 so as to be located near the ground, i.e., below the tension balancer 100, in order to facilitate the discharge of water that has entered the interior of the tension balancer 100. On the other hand, the multiple grooves 123 are positioned at a rotation of α + a × 90 degrees clockwise with respect to the center 170 of the first front spring washer 122. In the example shown in Figure 4, α is 45 degrees, and each of the multiple grooves 123 shown in Figure 4 is provided at a position rotated 45 degrees (when the value a is 0), 135 degrees (when the value a is 1), 225 degrees (when the value a is 2), and 315 degrees (when the value a is 3) clockwise with respect to the center 170 of the drain hole 125. Note that the example shown in Figure 4 is just one example, and the value a is not limited to 45 degrees. 【0036】For example, if the fastener 126 is positioned 180 degrees clockwise around the center 170 relative to the drain hole 125, the fastener 126 may not fall even if the second cylindrical member 130 is pulled further, and the worker may not be able to retrieve the fastener 126. Also, for example, if the fastener 126 is positioned in the same location as the drain hole 125, the removed fastener 126 may be driven back into the groove 123 by the restoring force of the first coil spring 128, even if the second cylindrical member 130 is pulled further. On the other hand, when installing the tension balancer 100 having the above structure and multiple grooves 123 on an overhead line, the fixing device 126 is positioned at a location rotated α + a × 90 degrees clockwise with respect to the center 170 of the first front spring washer 122. Therefore, when a worker removes the fixing device 126 from the multiple grooves 123, the fixing device 126 easily detaches from the multiple grooves 123 and falls below the tension balancer 100, allowing the worker to easily retrieve the fixing device 126. 【0037】 Furthermore, as explained in "1. Overall Structure," the second front spring washer 132 has the same configuration as the first front spring washer 122. Specifically, as shown in Figures 3 and 5, the second front spring washer 132 has the following configurations 1 to 7. In addition, the second front spring washer 132 has the same effect as the first front spring washer 122. 【0038】Configuration 1: The shape is ring-shaped, surrounding the third cylindrical member 140, and is fixed in front of the tension balancer 100. More specifically, it is fixed in front of the inner circumferential surface of the second cylindrical member 130 by a connecting member 124, and is also provided in front of the second cylindrical member 130. The second front spring washer 132 is separated from the third cylindrical member 140. Configuration 2: A part of the second cylindrical member 130 is closed, and the opening in the second cylindrical member 130 that is not closed by the second front spring washer 132 acts as an opening for the third cylindrical member 140 to slide inside the second cylindrical member 130, exposing a part of it from the second cylindrical member 130. Configuration 3: It is sandwiched between the second cylindrical member 130 and the third cylindrical member 140. Configuration 4: Includes a plurality of grooves 133, to which a plurality of fasteners 126 are detachably fixed in a one-to-one manner. Configuration 5: The number of grooves 133 is, for example, four. There is no limit to the number of grooves 133, and the number of grooves 133 can be generally expressed as k, where k is a natural number. The number of grooves 123 may be set as appropriate depending on the application or specifications of the tension balancer 100. Configuration 6: Includes a drain hole 135. The drain hole 135 is provided in a different position from the plurality of grooves 133. The drain hole 135 is an opening for draining water that has entered the inside of the tension balancer 100, and is provided near the ground, i.e., below the tension balancer 100, so that water that has entered the inside of the tension balancer 100 can be easily drained. Configuration 7: When the ring-shaped second front spring washer 132 is considered as a circle with diameter DM2 (diameter DM2 < diameter DM1), the drain hole 135 is provided on a virtual axis 182 parallel to the third direction D3 passing through the center 180 of the circle, and each of the multiple grooves 133 is provided at a position rotated α + a × 90 degrees clockwise around the drain hole 135 with respect to the center 180. The numerical value a is an integer greater than or equal to 0. The multiple grooves 133 are positioned at a position rotated α + a × 90 degrees clockwise around the center 180 of the second front spring washer 132. The example shown in Figure 5 is an example where α is 45 degrees. 【0039】[4. Rear Spring Washers] Referring to Figures 2 to 6, the configuration of the first rear spring washer 134 and the configuration of the second rear spring washer 144 will be described. When describing the rear spring washers of the tension balancer 100, configurations identical or similar to those in Figures 1 to 6 will be described as necessary, and the description of configurations identical or similar to those in Figures 1 to 6 may be omitted. 【0040】 For example, as shown in Figures 1, 2, or 6, a ring-shaped first rear spring washer 134 surrounding the second cylindrical member 130 is provided at one end of the tension balancer 100 on the rear side (rear hook 110 side). The first rear spring washer 134 is sandwiched between the first cylindrical member 120 and the second cylindrical member 130 and fixed to the rear of the outer circumferential surface of the second cylindrical member 130 (the surface on the first cylindrical member 120 side) by a connecting member 124. The first rear spring washer 134 is also spaced apart from the first cylindrical member 120. If the first rear spring washer 134 is considered as a circle, its diameter is greater than diameter DM2 and less than diameter DM1. 【0041】 A detailed illustration of the first rear spring washer 134 is omitted, but for example, the shape of the first rear spring washer 134 is similar to the ring shape of the first front spring washer 122 shown in Figure 4, which does not include the multiple grooves 123. Also, for example, if the first rear spring washer 134 is considered as a circle, the diameter of the first rear spring washer 134 is greater than the diameter DM2 and less than the diameter DM1. 【0042】Also, as described in "1. Overall Structure", the second rear spring washer 144 has the same configuration as the first rear spring washer 134. Specifically, the second rear spring washer 144 has configurations 8 to 10 shown below. Configuration 8: The shape is ring-shaped surrounding the third cylindrical member 140 and is fixed to the rear of the tension balancer 100. More specifically, it is fixed to the outer peripheral surface (the side of the second cylindrical member 130) of the third cylindrical member 140 by the connecting member 124 and is provided behind the third cylindrical member 140. Also, the second rear spring washer 144 is separated from the second cylindrical member 130. Configuration 9: It is sandwiched between the second cylindrical member 130 and the third cylindrical member 140. Configuration 10: When the second rear spring washer 144 is regarded as a circle, the diameter of the second rear spring washer 144 is smaller than the diameter DM2 and is the outer peripheral length of the outer peripheral surface of the third cylindrical member 140 / π. 【0043】 Although detailed illustration of the second rear spring washer 144 is omitted, for example, the shape of the second rear spring washer 144 is similar to a ring shape that does not include the plurality of grooves 133 of the second front spring washer 132 shown in FIG. 5. Also, for example, when the second rear spring washer 144 is regarded as a circle, the diameter of the second rear spring washer 144 is larger than the outer peripheral length of the outer peripheral circle of the third cylindrical member 140 / π and smaller than the diameter DM2. 【0044】 [5. Coil Spring, Second Back Plate and Guide Plate] Referring to FIG. 2 or FIG. 6, the configurations of the first coil spring 128 and the second coil spring 138 will be described. When explaining the coil springs of the tension balancer 100, configurations identical or similar to those in FIGS. 1 to 6 may be described as necessary, and the description of configurations identical or similar to those in FIGS. 1 to 6 may be omitted. 【0045】For example, as shown in Figure 2 or Figure 6, the first coil spring 128 surrounds the second cylindrical member 130 and is positioned between the first front spring washer 122 and the first rear spring washer 134 in the space between the inner circumferential surface of the first cylindrical member 120 and the outer circumferential surface of the second cylindrical member 130. For example, the elastic force of the compressed first coil spring 128 attempting to extend pushes the first front spring washer 122 and the first rear spring washer 134 in opposite directions along the first direction D1. The first front spring washer 122 is fixed to the first cylindrical member 120, and the first rear spring washer 134 is fixed to the second cylindrical member 130. As a result, the elastic force of the first coil spring 128 generates a force that pulls the second cylindrical member 130 into the first cylindrical member 120. Therefore, the tension balancer 100 can apply tension to the overhead wire connected to the front hook 150. 【0046】 Similar to the first coil spring 128, the second coil spring 138 surrounds the third cylindrical member 140 and is positioned between the second front spring washer 132 and the second rear spring washer 144 in the space between the inner circumferential surface of the second cylindrical member 130 and the outer circumferential surface of the third cylindrical member 140. For example, similar to the first coil spring 128, the elastic force of the compressed second coil spring 138 attempting to extend pushes the second front spring washer 132 and the second rear spring washer 144 in opposite directions. Since the second front spring washer 132 is fixed to the second cylindrical member 130 and the second rear spring washer 144 is fixed to the third cylindrical member 140, the elastic force of the second coil spring 138 generates a force that pulls the third cylindrical member 140 into the second cylindrical member 130. Therefore, the tension balancer 100 can apply tension to the overhead wire connected to the front hook 150. 【0047】 For example, as shown in Figures 2 and 6, in an arbitrary configuration, the second back plate 148 may be provided so as to cover a part of the third cylindrical member 140, and the plate-shaped guide plate 152 may be provided so as to pass through the slit in the second back plate 148. The guide plate 152 may function as a rear hook 110, and the rear hook 110 may be fixed to the end of the guide plate 152. 【0048】 When the second cylindrical member 130 and the third cylindrical member 140 slide along the first direction D1 with respect to the first cylindrical member 120, the first coil spring 128 and the second coil spring 138 expand and contract along the first direction D1. At this time, the first coil spring 128 and the second coil spring 138 may rotate about the first direction D1, and as a result, the second cylindrical member 130 and the third cylindrical member 140 may also rotate. As an arbitrary configuration, the tension balancer 100 has the second back plate 148 and the guide plate 152, so that the rotation of the third cylindrical member 140 arranged at the innermost side is suppressed. As a result, the rotation of the second cylindrical member 130 located between the first cylindrical member 120 and the third cylindrical member 140 having the minimum diameter can also be suppressed. 【0049】 [6. Fixture] Referring to FIGS. 7 and 8, the configuration of the fixture of the tension balancer 100 will be described. FIGS. 7 and 8 are a side view of the fixture of the tension balancer 100 viewed along the second direction D2 from the side assuming a plane parallel to the first direction D1 and the third direction D3, and a rear view of the fixture of the tension balancer 100 viewed along the first direction D1 from the side assuming a plane parallel to the second direction D2 and the third direction D3. The fixture of the tension balancer 100 may have any configuration shown in FIGS. 7 and 8. Also, the fixture of the tension balancer 100 is not limited to the configuration shown in FIGS. 7 and 8, and various modifications are possible. The fixture of the tension balancer 100 is not limited to the configuration shown in FIGS. 7 and 8, and various modifications are possible. When explaining the fixture of the tension balancer 100, configurations identical or similar to those in FIGS. 1 to 6 may be explained as necessary, and the explanation of configurations identical or similar to those in FIGS. 1 to 6 may be omitted. For example, the fixture shown in FIGS. 7 and 8 shows a fixture arranged above the guide plate 152 shown in FIG. 6. 【0050】The fasteners for the tension balancer 100 may be referred to as fasteners, crimps, or wedges. For example, the fasteners for the tension balancer 100 include the configuration described in any of sections 1. Overall Structure to 5. Coil Spring, Second Back Plate, and Guide Plate. The configuration of the fasteners for the tension balancer 100 can be appropriately modified depending on the application and specifications of the tension balancer 100. 【0051】 [6-1. Fixing device 126] As shown in Figure 7, the fixing device 126 includes an inclined portion 126S and a bottom portion 126B. For example, the inclined portion 126S may be referred to as an inclined surface, and the bottom portion 126B may be referred to as a bottom surface. The bottom portion 126B is the portion (surface) that contacts the outer circumferential surface of each cylindrical member. The length of the bottom portion 126B along the first direction D1 is length L1, and the length of the bottom portion 126B along the second direction D2 is length W1. The inclined portion 126S gradually inclins along the first direction D1 toward the direction in which the fixing member is driven, and the angle between the inclined portion 126S and the bottom portion 126B is angle θ. For example, as shown in Figure 7, angle θ is an acute angle. Also, for example, the shape of the side of the fixing device 126 is a trapezoid shape in which the length L1 of the bottom portion 126B is longer than the length of the top surface, and the shape of the back of the fixing device 126 is a square shape. 【0052】 For example, when the fastener 126 is driven into the groove 123, a portion of the inclined portion 200S contacts the groove 123, and a portion of the bottom portion 126B contacts the outer circumferential surface of the second cylindrical member 130. When the fastener 126 is driven into the groove 133, a portion of the inclined portion 126S contacts the groove 133, and a portion of the bottom portion 126B contacts the outer circumferential surface of the third cylindrical member 140. 【0053】 When the fastener 126 is driven into the groove 123, the fastener 126 comes into contact with the first front spring washer 122 and the second cylindrical member 130 and can act as a wedge to fix the first front spring washer 122 and the second cylindrical member 130. Also, when the fastener 126 is driven into the groove 133, the fastener 126 comes into contact with the second front spring washer 132 and the third cylindrical member 140 and can act as a wedge to fix the second front spring washer 132 and the third cylindrical member 140. 【0054】Furthermore, because the length L1 of the bottom portion 126B is longer than the length of the top surface, the contact area (area of ​​contact) between the fastener 126 and each cylindrical member is increased, thereby increasing the frictional force when the fastener 126 contacts each cylindrical member. As a result, the fastener 126 can firmly fix the first front spring washer 122 and the second cylindrical member 130. 【0055】 [6-2. Fixing device 200] As shown in Figure 7, the fixing device 200 includes an inclined portion 200S, a bottom portion 200B, and a flat end portion 200E. The end portion 200E connects the end of the inclined portion 200S and the end of the bottom portion 200B along the third direction D3, and is in contact with the end of the inclined portion 200S and the end of the bottom portion 200B. For example, the inclined portion 200S may be referred to as an inclined surface, the bottom portion 200B may be referred to as a bottom surface, and the end portion 200E may be referred to as a flat portion. In addition, the fixing device 200 differs from the fixing device 126 in that it does not include the acute angle portion of the fixing device 126 and includes the end portion 200E. The bottom portion 200B is the portion (surface) that is in contact with the outer circumferential surface of each cylindrical member. The length of the bottom portion 200B along the first direction D1 is length L2, and the length of the bottom portion 200B along the second direction D2 is length W1. The inclined portion 200S is inclined along the first direction D1 toward the direction in which the fixing member is driven. For example, the side shape of the fixing device 200 is a pentagon, where the length L2 of the bottom portion 200B is longer than the length of the top surface. 【0056】 For example, when the fastener 200 is driven into the groove 123, a portion of the inclined portion 200S contacts the groove 123, and a portion of the bottom portion 200B contacts the outer circumferential surface of the second cylindrical member 130. When the fastener 200 is driven into the groove 133, a portion of the inclined portion 200S contacts the groove 133, and a portion of the bottom portion 200B contacts the outer circumferential surface of the third cylindrical member 140. 【0057】 Similar to the fastener 126, the fastener 200 can contact the first front spring washer 122 and the second cylindrical member 130 and act as a wedge to fix the first front spring washer 122 and the second cylindrical member 130, and can also contact the second front spring washer 132 and the third cylindrical member 140 and act as a wedge to fix the second front spring washer 132 and the third cylindrical member 140. 【0058】The fixing device 200 has a bottom portion 200B that contacts each cylindrical member, and the length of the bottom portion 200B that contacts each cylindrical member is longer than the length of the top portion. This allows the frictional force when the fixing device 200 contacts each cylindrical member to be increased, and thus the fixing device 200 can firmly fix the front spring washer and the cylindrical member in the same way as the fixing device 126. 【0059】 [6-3. Fixing device 202] As shown in Figure 7, the fixing device 202 includes an inclined portion 202S, a bottom portion 202B, and a flat end portion 202E. The end portion 202E connects the end of the inclined portion 202S and the end of the bottom portion 202B along the third direction D3, and is in contact with the end of the inclined portion 202S and the end of the bottom portion 202B. In addition, in a rear view, the fixing device 202 includes a concave arc-shaped portion (arch portion) 202A extending from the side towards the center along the second direction D2, in other words, a concave arc-shaped portion (arch portion) 202A in the third direction D3. For example, the inclined portion 202S may be referred to as an inclined surface, the bottom portion 202B may be referred to as a bottom surface, the end portion 202E may be referred to as a flat portion, and the arch portion 202A may be referred to as an arch surface. The fastener 202 differs from the fastener 126 in that it does not include the acute angle portion of the fastener 126, and includes the end portion 202E and the arch portion 202A. 【0060】 For example, the arch portion 202A is the part (surface) that contacts the outer surface of each cylindrical member, and the arch portion 202A has the same shape as the outer surface of each cylindrical member so as to firmly contact the outer surface of each cylindrical member. The length of the bottom portion 202B along the first direction D1 is length L2, and the length of the bottom portion 202B along the second direction D2 is length W1. The inclined portion 202S is gradually inclined along the first direction D1 toward the direction in which the fixing member is driven. For example, the shape of the side surface of the fixing device 202 is a pentagon shape in which the length L2 of the bottom portion 202B is longer than the length of the top surface, similar to the fixing device 200. 【0061】 For example, when the fastener 202 is driven into the groove 123, a part of the inclined portion 202S contacts the groove 123, and a part of the arch portion 202A contacts the outer circumferential surface of the second cylindrical member 130. When the fastener 202 is driven into the groove 133, a part of the inclined portion 202S contacts the groove 133, and a part of the arch portion 202A contacts the outer circumferential surface of the third cylindrical member 140. 【0062】Similar to fasteners 126 and 200, fastener 202 can contact the first front spring washer 122 and the second cylindrical member 130 and act as a wedge to fix the first front spring washer 122 and the second cylindrical member 130, and can also contact the second front spring washer 132 and the third cylindrical member 140 and act as a wedge to fix the second front spring washer 132 and the third cylindrical member 140. 【0063】 The fastener 202 has an arched portion 202A that has the same shape as the outer circumferential surface of each cylindrical member, and the frictional force when the fastener 202 contacts each cylindrical member can be increased, so the fastener 200 can fix the front spring washer and the cylindrical member more firmly, similar to the fastener 126. In addition, because the fastener 202 has an arched portion 202A and the fastener 202 is driven in along the outer circumferential surface of each cylindrical member, the fastener 202 can suppress damage to the outer circumferential surface of the cylindrical member. 【0064】 [6-4. Fixing device 204] As shown in Figure 8, the fixing device 204 includes an inclined portion 204S, a bottom portion 204B, a notched portion 204N, and an end portion 204E. For example, the inclined portion 204S may be referred to as an inclined surface, the bottom portion 204B may be referred to as a bottom surface, and the end portion 204E may be referred to as a flat portion. The fixing device 204 differs from the fixing device 126 in that it does not include the acute angle portion of the fixing device 126, and includes the notched portion 204N and the end portion 204E. 【0065】 The notch 204N, in a side view, is provided between the end of the inclined portion 204S and the end of the bottom portion 204B, and has a crow-beak shape with a first surface 204N1 that slopes upward from below in the direction in which the fixing member is driven along the first direction D1, and a second surface 204N2 that slopes downward from above in the direction in which the fixing member is driven along the first direction D1. The lower end of the second surface 204N2 is in contact with the flat end 204E. 【0066】For example, the bottom portion 204B is the part (surface) that contacts the outer circumferential surface of each cylindrical member. The length of the bottom portion 204B along the first direction D1 is length L2, and the length of the bottom portion 204B along the second direction D2 is length W1. The inclined portion 204S is gradually inclined along the first direction D1 toward the direction in which the fixing member is driven. For example, in a side view, the length L2 of the bottom portion 204B is longer than the length of the top surface. 【0067】 Since the fixing device 204 can increase the frictional force when it contacts each cylindrical member, the fixing device 204 can firmly fix the front spring washer and the cylindrical member in the same way as the fixing device 126. 【0068】 For example, when the fastener 204 is driven into the groove 123, a part of the inclined portion 204S contacts the groove 123, and a part of the bottom portion 204B contacts the outer circumferential surface of the second cylindrical member 130. When the fastener 204 is driven into the groove 133, a part of the inclined portion 204S contacts the groove 133, and a part of the bottom portion 204B contacts the outer circumferential surface of the third cylindrical member 140. As shown in the lower part of Figure 8, when the fastener 204 is driven into the groove 123 or 133, the ruler-shaped shape of the fastener 204 changes from the dashed line state to the solid line state, with the first surface 204N1 and the second surface 204N2 in contact, resulting in a closed state. In this state, a force acts to separate the first surface 204N1 and the second surface 204N2, making it difficult for the fastener 204 to come out of the groove 123 or 133, and allowing the fastener 204 to more firmly fix the front spring washer and the cylindrical member. 【0069】 Furthermore, when the worker removes the fastener 204 from the multiple grooves 123 or 133, the first surface 204N1 and the second surface 204N2 are separated, making it difficult for the fastener 204 to be driven back into the grooves 123 or 133, thereby preventing the fastener 204 from being driven back into the grooves 123 or 133 against the worker's intention. 【0070】[7. Modified Examples] Modified examples of the tension balancer 100 will be described with reference to Figure 9. Figure 9 is an end view showing an example of an end cross-sectional structure obtained by cutting a modified example of the tension balancer 100 along the dashed line A1-A2 extending in the first direction D1 shown in Figure 1. When describing modified examples of the tension balancer 100, configurations identical or similar to those in Figures 1 to 8 will be described as necessary, and descriptions of configurations identical or similar to those in Figures 1 to 8 may be omitted. 【0071】 A modified version of the tension balancer 100 includes configuration 1 shown below. (Configuration 1) A configuration in which one first coil spring 128 and one second coil spring 138 in the tension balancer 100 are replaced with two first coil springs 128A and 128B, and two second coil springs 138A and 138B, which are arranged in series. The configurations of the modified version of the tension balancer 100 other than configuration 1 are the same as the configuration of the tension balancer 100. Therefore, the configurations of the modified version of the tension balancer 100 other than configuration 1 will be described as necessary. 【0072】 For example, in the modified version of the tension balancer 100 shown in Figure 9, the second cylindrical member 130 is pulled out from the first cylindrical member 120, and the first coil springs 128A and 128B are compressed. The fixing device 126 is positioned in the groove 123 of the first front spring washer 122 so as to maintain the elastic force (restoring force) that causes the first coil springs 128A and 128B to return to their original length. Another modified version of the tension balancer 100 shown in Figure 9 is the third cylindrical member 140 is pulled out from the second cylindrical member 130, and the second coil springs 138A and 138B are compressed. The fixing device 126 is positioned in the groove 133 of the second front spring washer 132 so as to maintain the elastic force (restoring force) that causes the second coil springs 138A and 138B to return to their original length. 【0073】As shown in Figure 9, the first coil spring 128A includes a grinding surface 129A, and the first coil spring 128B includes a grinding surface 129B. The first coil springs 128A and 128B are arranged in series in a direction parallel to the coil axes of the first coil springs 128A and 128B (first direction D1). The grinding surface 129A is in contact with the grinding surface 129B in the state before the second cylindrical member 130 is pulled out from the first cylindrical member 120, and in the state shown in Figure 9 when the second cylindrical member 130 is pulled out from the first cylindrical member 120. 【0074】 Furthermore, the first coil springs 128A and 128B are positioned between the first cylindrical member 120 and the second cylindrical member 130. More specifically, the first coil springs 128A and 128B surround the second cylindrical member 130 and are positioned between the first front spring washer 122 and the first rear spring washer 134 in the space between the inner circumferential surface of the first cylindrical member 120 and the outer circumferential surface of the second cylindrical member 130. 【0075】 Similar to the first coil springs 128A and 128B, the second coil spring 138A includes a grinding surface 139A, and the second coil spring 138B includes a grinding surface 139B. The second coil springs 138A and 138B are arranged in series in a direction parallel to the coil axes of the second coil springs 138A and 138B (first direction D1). Similar to the grinding surfaces 129A and 129B, the grinding surface 139A is in contact with the grinding surface 139B in the state before the second cylindrical member 130 is pulled out from the first cylindrical member 120, and in the state shown in Figure 9 when the second cylindrical member 130 is pulled out from the first cylindrical member 120. 【0076】 Furthermore, the second coil springs 138A and 138B are positioned between the second cylindrical member 130 and the third cylindrical member 140. More specifically, similar to the first coil springs 128A and 128B, the second coil springs 138A and 138B surround the third cylindrical member 140 and are positioned between the second front spring washer 132 and the second rear spring washer 144 in the space between the inner circumferential surface of the second cylindrical member 130 and the outer circumferential surface of the third cylindrical member 140. 【0077】Furthermore, in the first front spring washer 122, the second front spring washer 132, the first rear spring washer 134, and the second rear spring washer 144, the first front spring washer 122, selected from the first front spring washer 122 and the second front spring washer 132, and the first rear spring washer 134, selected from the first rear spring washer 134 and the second rear spring washer 144, surround the second cylindrical member 130 and are arranged to sandwich the first coil springs 128A and 128B along a direction parallel to the coil axes of the first coil springs 128A and 128B (first direction D1). Furthermore, the second front spring washer 132, selected from the first front spring washer 122 and the second front spring washer 132, and the second rear spring washer 144, selected from the first rear spring washer 134 and the second rear spring washer 144, surround the third cylindrical member 140 and are arranged to sandwich the second coil springs 138A and 138B along a direction parallel to the coil axes of the second coil springs 138A and 138B (first direction D1). 【0078】 For example, we compare the compression of a first tension balancer (referred to as the first tension balancer) when a load is applied to it, with the compression of a second tension balancer (referred to as the second tension balancer) when a load is applied to it, which contains two coil springs with spring constant K arranged in series. When the same load is applied to both the first and second tension balancers, the second tension balancer is compressed twice as much as the first tension balancer. That is, the apparent spring constant of the second tension balancer becomes 1 / 2K. Also, for example, when a load is applied to the second tension balancer, both coil springs are compressed similarly, rather than one coil spring being compressed before the other. 【0079】In other words, when the spring constants of the two first coil springs 128A and 128B are the same, and the spring constants of the two second coil springs 138A and 138B are also the same, a modified version of the tension balancer 100 including two first coil springs 128A and 128B and two second coil springs 138A and 138B arranged in series can reduce the apparent spring constant compared to a tension balancer including one coil spring (i.e., a tension balancer including one first coil spring 128A and one second coil spring 138A), thereby increasing the stroke during compression. Therefore, the modified version of the tension balancer 100 can apply greater tension to the overhead wire connected to the front hook 150 than a tension balancer including one coil spring. 【0080】 Furthermore, a modified version of the tension balancer 100 can be constructed by driving a relatively simple fastener 126 into the groove 123 of the first front spring washer 122 to fix the second cylindrical member 130, which has been pulled out from the first cylindrical member 120, in a compressed state of the first coil springs 128A and 128B, so as to maintain the elastic force (restoring force) that causes the first coil springs 128A and 128B to return to their original length. Alternatively, another fastener 126 can be driven into the groove 133 of the second front spring washer 132 to fix the third cylindrical member 140, which has been pulled out from the second cylindrical member 130, in a compressed state of the second coil springs 138A and 138B, so as to maintain the elastic force (restoring force) that causes the second coil springs 138A and 138B to return to their original length. A modified version of the tension balancer 100 includes two first coil springs 128A and 128B arranged in series, and two second coil springs 138A and 138B arranged in series. As a result, the elastic force (restoring force) that tries to return to its original length is greater than that of a single coil spring, allowing for a more secure fixation between the second cylindrical member 130, which is drawn out from the first cylindrical member 120, and the fastener 126, as well as a more secure fixation between the third cylindrical member 140, which is drawn out from the second cylindrical member 130, and the other fastener 126. 【0081】The number of first coil springs 128 and second coil springs 138 arranged in series is not limited to the configuration shown in the tension balancer 100 or the modified version of the tension balancer 100. For example, the number of first coil springs 128 and second coil springs 138 arranged in series can be adjusted as appropriate depending on the specifications and application of the tension balancer 100 or the modified version of the tension balancer 100, and may be three or more. 【0082】 The tension balancers according to each embodiment described above can be combined as appropriate, as long as they do not contradict each other. Furthermore, any additions, deletions, or design modifications made by those skilled in the art based on each embodiment are also included within the scope of the present invention, as long as they retain the essence of the present invention. 【0083】 Furthermore, any effects or benefits other than those brought about by the tension balancers according to the embodiments described above, if they are clear from the description herein or easily predictable to those skilled in the art, are naturally understood to be brought about by the present invention. 【0084】100: Tension balancer, 102: Support plate, 104: First back plate, 106: U-shaped rod, 108: Collar, 110: Column-side mounting member (rear hook), 120: First cylindrical member, 122: First front spring washer, 123: Groove, 124: Connecting member, 125: Drainage hole, 126: Fixing device, 126B: Bottom, 126S: Inclined part, 128: First coil spring, 128A: First coil spring, 128B: First coil spring, 129A: Grinding surface, 129B: Grinding surface, 130: Second cylindrical member, 132: Second front spring washer, 133: Groove, 134: First rear spring washer, 135: Drainage hole, 138: Second coil spring, 138A: Second Coil spring, 138B: Second coil spring, 139A: Ground surface, 139B: Ground surface, 140: Third cylindrical member, 144: Second rear spring washer, 148: Second back plate, 150: Overhead line side mounting member (front hook), 152: Guide plate, 170: Center, 172: Virtual axis, 180: Center, 182: Virtual axis, 2 00: Fixing device, 200B: Bottom, 200E: End, 200S: Inclined section, 202: Fixing device, 202A: Arc-shaped section (arch section), 202B: Bottom, 202E: End, 202S: Inclined section, 204: Fixing device, 204B: Bottom, 204E: End, 204N: Notch, 204N1: First surface, 204N2: Second surface, 204S: Inclined section

Claims

1. The device comprises: first to nth cylindrical members, first to (n-1)th coil springs, a rear hook attached to the first cylindrical member, a front hook attached to the nth cylindrical member, first to (n-1)th front spring washers including a plurality of grooves, first to (n-1)th rear spring washers, and a plurality of fasteners detachably fixed one-to-one in the plurality of grooves, wherein the first to nth cylindrical members are arranged such that the (m+1)th cylindrical member selected from the first to nth cylindrical members is located inside the mth cylindrical member selected from the first to nth cylindrical members, and the first to (n-1)th coil springs are arranged such that the mth coil spring selected from the first to (n-1)th coil springs is sandwiched between the mth cylindrical member and the (m+1)th cylindrical member. The first to (n-1) front spring washers and the first to (n-1) rear spring washers are arranged such that the m-th front spring washer selected from the first to (n-1) front spring washers and the m-th rear spring washer selected from the first to (n-1) rear spring washers surround the (m+1) cylindrical member, and sandwich the m coil spring in a direction parallel to the coil axis of the m coil spring; each of the first to (n-1) front spring washers is fixed to the first to (n-1) cylindrical member and surrounds the first to (n-1) cylindrical member; each of the plurality of fasteners is in contact with the grooves of the plurality of grooves of the m front spring washer, in a one-to-one correspondence, and with the (m+1) cylindrical member, and restricts the movement of the (m+1) cylindrical member in the aforementioned direction; A tension balancer where n is a natural number between 2 and 5 (inclusive), and m is a natural number between 1 and (n-1) (inclusive).

2. The tension balancer according to claim 1, wherein each of the first to (n-1) rear spring washers is fixed to the second to nth cylindrical members and surrounds the second to nth cylindrical members.

3. The tension balancer according to claim 1, wherein the plurality of grooves of the front spring washer m are k, where k is a natural number.

4. The tension balancer according to claim 1, wherein the fastener includes a bottom portion aligned with the direction and an inclined portion angled with the bottom portion aligned with the direction, a part of the inclined portion contacts the groove of the front spring washer m, and a part of the bottom portion contacts the cylindrical member (m+1).

5. The tension balancer according to claim 1, wherein the fastener includes a bottom portion aligned with the direction, an inclined portion that gradually slopes along the direction, and a flat portion that contacts the end of the bottom portion and the end of the inclined portion, wherein a part of the inclined portion contacts the groove of the front spring washer m, and a part of the bottom portion contacts the cylindrical member (m+1).

6. The tension balancer according to claim 1, wherein the fastener includes a bottom portion aligned with the direction, an inclined portion that gradually slopes along the direction, and a flat portion that contacts the end of the bottom portion and the end of the inclined portion, the bottom portion includes an arc-shaped surface, a part of the inclined portion contacts the groove of the front spring washer m, and a part of the arc-shaped surface contacts the cylindrical member (m+1).

7. The tension balancer according to claim 1, wherein the fastener includes a bottom portion aligned with the direction, an inclined portion that gradually slopes along the direction, and a notch provided between the end of the bottom portion and the end of the inclined portion, including a first surface and a second surface, wherein a part of the inclined portion contacts the groove of the front spring washer m, a part of the bottom portion contacts the cylindrical member (m+1), and a part of the first surface contacts the second surface.

8. The tension balancer according to claim 1, wherein the first to (n-1) front spring washers include drainage holes provided at positions different from the plurality of grooves.

Images