Tension balancer

Abstract

To provide a tension balancer which can be used for a long period of time at a proper stroke length.SOLUTION: A tension balancer comprises first to n-th cylinder members, first to (n-1)th coil springs, a first hook attached to the first cylinder member, a second hook attached to the n-th cylinder member, and a scale attached to the n-th cylinder member. The scale extends in a first direction parallel with center axes of the first to n-th cylinder members, is located outside the n-th cylinder member, overlapped on n-th cylinder member in a second direction which is vertical to the first direction, and is able to be telescopic in the first direction. The first to n-th cylinder members are arranged so that a j-th cylinder member selected from the first to n-th cylinder members is surrounded by a (j+1)th cylinder member. The cylinder members and the coil springs are alternately arranged. The n is a natural number equal to or larger than 3, and the j is a variable which is selected from a natural number which is equal to or larger than 1, and equal to or smaller than (n-1).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to a tension balancer that can be used on an overhead line. [Background technology]

[0002] Tension balancers are attached to overhead wires of railways and the like as devices for pulling the wires with the appropriate tension even when expansion and contraction occur due to temperature changes. For example, Patent Documents 1 and 2 disclose tension balancers whose basic configuration consists of multiple cylindrical members arranged coaxially and coil springs arranged between the cylindrical members. In addition, a scale with a graduation is attached to the tension balancer as an index for measuring the displacement, which makes it possible to grasp the condition of the coil springs inside the tension balancer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-108766 A [Patent Document 2] JP 2009-303301 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the embodiment of the present invention is to provide a tension balancer having a novel structure, or to provide a tension balancer that can be used with an appropriate stroke length for a long period of time. [Means for solving the problem]

[0005] One embodiment of the present invention is a tension balancer. The tension balancer includes first to n-th cylindrical members, first to (n-1)-th coil springs, a first hook attached to the first cylindrical member, a second hook attached to the n-th cylindrical member, and a scale attached to the n-th cylindrical member. The scale extends in a first direction parallel to the central axis of the first to n-th cylindrical members, is located outside the n-th cylindrical member, overlaps with the n-th cylindrical member in a second direction perpendicular to the first direction, and is configured to be expandable and contractible in the first direction. The first to n-th cylindrical members are arranged such that a j-th cylindrical member selected from the first to n-th cylindrical members is surrounded by a (j+1)-th cylindrical member selected from the first to n-th cylindrical members. The cylindrical members and the coil springs alternate with each other. n is a natural number equal to or greater than 3, and j is a variable selected from natural numbers equal to or greater than 1 and equal to or less than (n-1). [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic perspective view of a tension balancer according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic end view of a tension balancer according to an embodiment of the present invention. [Figure 3A] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 3B] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 3C] FIG. 2 is a schematic end view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 4A] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 4B] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 5A] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 5B] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 6A]FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 6B] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 6C] FIG. 2 is a schematic end view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 7A] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 7B] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 7C] FIG. 2 is a schematic end view of a portion of the tension balancer according to the embodiment of the present invention. [Figure 8] FIG. 2 is a schematic side view of a portion of the tension balancer according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, each embodiment of the invention disclosed in this application will be described with reference to the drawings. However, the present invention can be embodied in various forms without departing from the gist of the invention, and the present invention should not be interpreted as being limited to the description of the embodiments exemplified below.

[0008] In order to clarify the description, the drawings may show the width, thickness, shape, etc. of each part in a schematic manner compared to the actual embodiment, but these are merely examples and do not limit the interpretation of the present invention. In this specification and each drawing, elements having the same functions as those explained in the previous drawings may be given the same reference numerals, and duplicate explanations may be omitted.

[0009] In this specification and drawings, the same reference numerals are used to collectively represent multiple identical or similar components, and a hyphen and a number are added after the reference numerals to represent each of the components individually. When multiple parts of a single component are to be distinguished from one another, the same reference numerals and alphabetical characters are used.

[0010] In this specification and claims, the expression "a structure is exposed from another structure" means an embodiment in which a part of a structure is not covered by another structure, and includes an embodiment in which the part not covered by the other structure is covered by yet another structure. The embodiment expressed by this expression also includes an embodiment in which a structure is not in contact with the other structure.

[0011] The following describes a tension balancer 100 according to an embodiment of the present invention. The tension balancer 100 can be used to tension an overhead wire with an appropriate tension.

[0012] 1.Overall structure FIG. 1 shows a schematic perspective view of a tension balancer 100. The tension balancer 100 is arranged coaxially and includes multiple cylindrical members with different outer diameters. The tension balancer 100 shown in FIG. 1 is a two-stage tension balancer with three cylindrical members, including a first cylindrical member 110, a second cylindrical member 120, and a third cylindrical member 130. There is no restriction on the number of cylindrical members, which is typically 2 to 4, and may be 5 or more. In the tension balancer 100, a part of a cylindrical member having a smaller outer diameter is inserted into a cylindrical member with a larger outer diameter. More specifically, if tension balancer 100 has first to nth (n is a natural number equal to or greater than 2) cylindrical members, with the outer diameter decreasing in the order from the first cylindrical member to the nth cylindrical member, the (j+1)th (j is a variable selected from natural numbers equal to or greater than 1 and including (n-1)) cylindrical member is arranged so as to be surrounded by the jth cylindrical member, and the (j+1)th cylindrical member can reversibly slide inside the jth cylindrical member in the direction of the central axis of each cylindrical member. Below, the explanation will continue using a two-stage tension balancer 100 (i.e., a tension balancer where n is 3).

[0013] A pole-side mounting member (hereinafter referred to as a first hook) 102 is attached directly or indirectly to one end of the first cylindrical member 110 having the largest outer diameter, and the tension balancer 100 can be connected to a fixed structure such as a pole by using this first hook 102. As an optional configuration, a hanger hook 106 and / or an opening (not shown) for hanging the tension balancer 100 when assembling or installing the tension balancer 100 may be provided on the upper part of the first cylindrical member 110. On the other hand, an overhead line-side mounting member (hereinafter referred to as a second hook) 104 that is connected to an overhead line is attached directly or indirectly to one end of the cylindrical member (here, the third cylindrical member 130) having the smallest outer diameter. As will be described later, a coil spring is arranged in a compressed state between adjacent cylindrical members, and multiple cylindrical members and multiple coil springs alternate with each other. The elastic force of the coil spring as it tries to expand generates a force that causes the outer cylindrical member to pull the adjacent inner cylindrical member inward. This force allows the overhead wire to be pulled with the appropriate tension.

[0014] Hereinafter, the length direction of tension balancer 100 is defined as the x direction, and the vertical direction when tension balancer 100 is installed so that the x direction is horizontal is defined as the z direction. The direction perpendicular to the x and z directions is defined as the y direction. The x direction is parallel to the central axis of tension balancer 100 and each cylindrical member, and is the direction in which the second to nth cylindrical members slide.

[0015] 2. First cylindrical member FIG. 2 shows a schematic diagram of an end surface along a chain line AA' extending in the x direction in FIG. 1. As shown in FIG. 2, a first back plate 140 forming a bottom surface can be provided at one end of the first cylindrical member 110 where the first hook 102 is arranged. The first hook 102 may be attached to the first back plate 140 by welding or bolting, or may be fixed to the first cylindrical member 110 without the first back plate 140. Although not shown, the first cylindrical member 110 may be provided with an opening for discharging water that has infiltrated inside. A falling prevention mechanism for preventing the second cylindrical member 120 and the third cylindrical member 130 from falling off is further provided at the one end where the first hook 102 is arranged. There are no restrictions on the structure of the falling prevention mechanism, and in the example shown in FIG. 1 and FIG. 2, a U-shaped bar 142 is provided as the falling prevention mechanism. The U-shaped bar 142 extends in a direction perpendicular to the z-direction and penetrates the first cylindrical member 110, and a collar 144 provided at the end of the U-shaped bar 142 prevents the U-shaped bar 142 from falling off. The first back plate 140 moves toward the first hook 102 due to the elastic forces of the first coil spring 112 provided between the first cylindrical member 110 and the second cylindrical member 120, and the second coil spring 122 provided between the second cylindrical member 120 and the third cylindrical member 130, but the movement is restricted by the U-shaped bar 142 and the first back plate 140.

[0016] A ring-shaped first front washer 114 is provided at the end of the first cylindrical member 110 opposite to the first hook 102 (i.e., the end on the second hook 104 side). The first front washer 114 can be provided so as to be surrounded by the first cylindrical member 110, and covers a part of the first cylindrical member 110. The opening of the first front washer 114 serves as an opening through which the second cylindrical member 120 slides inside the first cylindrical member 110 and a part of the second cylindrical member 120 is exposed from the first cylindrical member 110. Although not shown, the first front washer 114 may not be surrounded by the first cylindrical member 110, and the first front washer 114 having an outer diameter that is the same or substantially the same as the outer diameter of the first cylindrical member 110 may be provided so as to cover a part of the first cylindrical member 110. The first front washer 114 may also be integrated with the first cylindrical member 110.

[0017] 3. Second cylindrical member The second cylindrical member 120 is disposed within the first cylindrical member 110. A ring-shaped first rear washer 124 is provided at the end of the second cylindrical member 120 on the side of the first hook 102. In the example shown in FIG. 2, the first rear washer 124 is provided so as to surround the second cylindrical member 120, but the first rear washer 124 may not surround the second cylindrical member 120, and the first rear washer 124 having an inner diameter identical or substantially identical to the inner diameter of the second cylindrical member 120 may be provided at the end of the second cylindrical member 120. The first rear washer 124 may be integrated with the second cylindrical member 120. The first coil spring 112 is disposed between the first front washer 114 and the first rear washer 124 in the space between the first cylindrical member 110 and the second cylindrical member 120. Therefore, the compressed first coil spring 112 pushes out the first front washer 114 and the first rear washer 124 in opposite directions due to the elastic force of the spring trying to expand. As a result, a force is generated that pulls the second cylindrical member 120 into the first cylindrical member 110.

[0018] Similar to the first cylindrical member 110, a ring-shaped second front washer 126 is provided at the end of the second cylindrical member 120 on the second hook 104 side. The second front washer 126 can be provided so as to be surrounded by the second cylindrical member 120, and closes a part of the second cylindrical member 120. The opening of the second front washer 126 serves as an opening through which the third cylindrical member 130 slides within the second cylindrical member 120 and a part of the third cylindrical member 130 is exposed from the second cylindrical member 120. Although not shown, the second front washer 126 may not be surrounded by the second cylindrical member 120, and the second front washer 126 having an outer diameter identical or substantially identical to the outer diameter of the second cylindrical member 120 may be provided so as to close the second cylindrical member 120. The second front washer 126 may also be integrated with the second cylindrical member 120.

[0019] 4.Third cylindrical member Similar to the second cylindrical member 120, the third cylindrical member 130 is disposed within the second cylindrical member 120, and a ring-shaped second rear washer 132 is provided at the end of the third cylindrical member 130 on the first hook 102 side. In the example shown in FIG. 2, the second rear washer 132 is provided so as to surround the third cylindrical member 130, but the second rear washer 132 may not surround the third cylindrical member 130, and the second rear washer 132 having an inner diameter identical or substantially identical to the inner diameter of the third cylindrical member 130 may be provided at the end of the third cylindrical member 130. The second rear washer 132 may be integrated with the third cylindrical member 130. The second coil spring 122 is disposed between the second front washer 126 and the second rear washer 132 in the space between the second cylindrical member 120 and the third cylindrical member 130. Therefore, the compressed second coil spring 122 pushes the second front washer 126 and the second rear washer 132 in opposite directions due to the elastic force of the spring trying to expand. As a result, a force is generated that pulls the third cylindrical member 130 into the second cylindrical member 120.

[0020] When the second cylindrical member 120 and the third cylindrical member 130 slide relative to the first cylindrical member 110, the first coil spring 112 and the second coil spring 122 expand and contract, and at that time, the first coil spring 112 and the second coil spring 122 rotate around the x-direction, and as a result, the second cylindrical member 120 and the third cylindrical member 130 may also rotate. For this reason, as an optional configuration, a second back plate 134 having a slit may be provided on the first hook 102 side so as to cover a part of the third cylindrical member 130, and further, a plate-shaped guide plate 146 may be arranged to penetrate the slit of the second back plate 134. The guide plate 146 may be arranged to penetrate the first back plate 140. In this case, the guide plate 146 may function as the first hook 102, or the first hook 102 may be fixed to the end of the guide plate 146. By providing a second back plate 134 having a slit and a plate-shaped guide plate 146 that penetrates this slit, rotation of the third cylindrical member 130 located innermost is prevented, and therefore rotation of the cylindrical member (here, the second cylindrical member 120) located between the first cylindrical member 110 and the cylindrical member having the smallest diameter (here, the third cylindrical member 130) can also be regulated.

[0021] 5. Scale and pointer components As shown in FIG. 1 and FIG. 2, the third cylindrical member 130 located at the innermost position is fitted with a scale 150 extending in a direction parallel to the central axis of each cylindrical member (i.e., the x-direction). The scale 150 is located outside the third cylindrical member 130 and is provided so as to overlap the first to third cylindrical members 130 in the z-direction. The scale 150 and the third cylindrical member 130 are fixed to each other by any method, and even if the cylindrical members move, the relative distance and positional relationship between the third cylindrical member 130 and the scale 150 are constant and do not change. There is no restriction on the method of fixing the scale 150 and the third cylindrical member 130. For example, as shown in FIG. 1 and FIG. 2, a plate-shaped front plate 152 may be fixed to the end of the third cylindrical member 130, and the scale may be fixed to the front plate 152 by welding or bolting. Although not shown, instead of the front plate 152, the scale 150 and the third cylindrical member 130 may be fixed using a single rod or a plurality of posts.

[0022] A marking is provided on the outer surface of the scale 150. The marking may be formed, for example, by ink printed in stripes extending in a direction perpendicular to the x-direction, by tape wound around the scale 150, or by engraving.

[0023] Here, the scale 150 is configured so as to be reversibly expandable and contractable in the x direction (see the dotted arrow in FIG. 1). There are no restrictions on the mechanism for expanding and contracting in the x direction, and for example, as shown in FIG. 3A, the scale 150 may be configured to include a beam 156 fixed to the third cylindrical member 130, and a cylindrical slide member 154 that houses the beam 156. The memory is attached to the outer surface of the slide member 154.

[0024] The beam 156 is connected to the third cylindrical member 130 directly or via, for example, the front plate 152, and the relative positional relationship with the third cylindrical member 130 does not change. The shape of the end face (end face perpendicular to the x direction) of the beam 156 can also be set arbitrarily, and may be a polygon such as a circle, an ellipse, or a square. On the other hand, the slide member 154 is configured in a cylindrical shape so that it can move in the x direction along the beam 156 while accommodating the beam 156. The slide member 154 may be formed to have a through hole penetrating in the x direction, or may be formed to have a bottomed hole extending in the x direction. The shape of the through hole or bottomed hole of the slide member 154 (the shape of the end face perpendicular to the x direction) may be formed to match the shape of the end face of the beam 156. The slide member 154 may be configured to be detachable from the beam 156, or a stopper (not shown) may be provided to prevent the slide member 154 from falling off from the beam 156.

[0025] In addition, in order to fix the scale 150 at an arbitrary length, the beam 156 is provided with a plurality of through holes 156a arranged in the x direction. Similarly, the slide member 154 is provided with at least one through hole 154a arranged so as to overlap with the through hole 156a. The at least one through hole 154a may include a plurality of through holes 154a. As shown in FIG. 3B and the schematic diagram of the end surface along the chain line BB′ in FIG. 3B (FIG. 3C), for example, by inserting a bolt 158 ​​into the through holes 154a and 156a and fixing the bolt 158 ​​with a nut 160, the length of the scale 150 can be adjusted and fixed in units of the pitch of the through holes 156a. Note that, when fixing, a washer 162 may be used as an optional configuration together with the bolt 158 ​​and the nut 160. Although not shown, when the end surface shape of the slide member 154 has a curved surface, the washer 162 may also be configured to fit the curved surface.

[0026] The pointer member 170 is fixed to the cylindrical member located at the outermost position, i.e., the first cylindrical member 110. Therefore, its position is constant and does not depend on the expansion and contraction of the tension balancer 100. The pointer member 170 overlaps with the scale 150 in the z direction, and is disposed so that the scale 150 is sandwiched between the first cylindrical member 110 and the pointer member 170. The pointer member 170 functions as a reference for reading the markings attached to the scale 150. If this function can be realized, the configuration of the pointer member 170 can be determined arbitrarily, and for example, the pointer member 170 may be configured to include a rod or a flat plate extending in the y direction. In addition, the method of fixing the pointer member 170 to the first cylindrical member 110 may be arbitrary, and bolting, welding, or the like may be used.

[0027] The tension balancer 100 is used within a stroke range where an appropriate tension is obtained, taking into consideration the stroke-tension characteristics. The stroke length can be grasped using the scale 150 and the pointer member 170, and the state of the coil spring can be grasped from the stroke length.

[0028] However, the characteristics of mass-produced tension balancers 100 are not necessarily all the same, and there is a certain level of variation. For this reason, if the length of the scale 150 cannot be adjusted, the initially set position of the scale 150 may be inappropriate. In extreme cases, the pointer member 170 may overlap outside the range of the memory, or the pointer member 170 may not overlap the scale in the z direction.

[0029] However, in a tension balancer 100 according to one embodiment of the present invention, the scale 150 is extendable in the x-direction, and can be fixed at any position in the x-direction. This makes it possible to precisely adjust the length of the scale 150 in accordance with the characteristic variations that occur during the manufacture of the tension balancer, and makes it possible to accurately grasp the stroke length of the tension balancer 100 when in use. This makes it possible to provide a tension balancer that can be used with an appropriate stroke length over a long period of time.

[0030] 6. Variations The configuration of the scale 150 is not limited to the above-mentioned configuration, and various modifications are possible. Modifications will be described below.

[0031] (1) Variation 1 For example, as shown in Fig. 4A, the beam 156 may be provided with a slit 156b extending in the x direction. The slit 156b may penetrate the beam 156 in the y direction, or, although not shown, may penetrate the beam 156 in the z direction. Here, the slit 156b is an opening having a longitudinal direction in the x direction, and the aspect ratio (length in the x direction / length in the z direction or y direction) is, for example, 5 or more and 30 or less. The beam 156 and the slide member 154 may be fixed by any method, and may be fixed by one or more bolts 158 and nuts 160 meshing with the bolts 158, as shown in Fig. 4B.

[0032] When the slit 156b is provided, the width of the slit 156b (the length in the z-direction or y-direction perpendicular to the x-direction) may be changed periodically in the x-direction, continuously or intermittently, in order to prevent the slide member 154 from moving unintentionally in the x-direction. For example, as shown in the enlarged views of the slit 156b (FIGS. 5A and 5B), the width may be changed continuously or intermittently by providing a convex portion 156c and a concave portion 156d on the inner wall constituting the slit 156b. The convex portion 156c and the concave portion 156d are formed so that the minimum width W2 is smaller than the outer diameter of the threaded portion of the bolt 158, and the maximum width W1 is larger than the outer diameter of the threaded portion of the bolt 158. By providing the slit 156b with such a shape, the slide member 154 can be prevented from moving unintentionally in the x-direction.

[0033] (2) Variation 2 Moreover, the slide member 154 does not necessarily have to surround the entire beam 156 on the end surface perpendicular to the x direction, and may be a groove type having a C-shape, for example, as shown in FIG. 6A, FIG. 6B, and the schematic diagram of the end surface along the chain line CC′ in FIG. 6B (FIG. 6C). In this case, the slide member 154 is provided so that the C-shaped opening faces the third cylindrical member 130 so that the markings attached to the slide member 154 can be visually confirmed. The beam 156 is formed into a plate shape so as to fit the shape of the groove of the slide member 154. As in the first modification, the slide member 154 and the beam 156 may be fixed to each other using a bolt 158 ​​passing through the slit 156b and the through hole 154a, a nut 160 meshing with the bolt 158, a washer 162, and the like. In addition to the through hole 154a used for fixing the slide member 154 to the beam 156, one or more through holes 154b for draining rainwater and the like may be formed in the slide member 154. The size of the through hole 154b may be smaller than that of the through hole 154a. Although not shown, similarly to the first modification, the width of the slit 156b may be changed periodically along the x direction and continuously or intermittently.

[0034] (3) Variation 3 Alternatively, as shown in FIG. 7A, the scale 150 may be configured such that the beam 156 and the slide member 154 are threaded, respectively, and the slide member 154 slides relative to the beam 156 by rotating the beam 156 around the x-direction. Specifically, the outer peripheral surface of the beam 156 is threaded in whole or in part, and the inner wall of the cylindrical slide member 154 is threaded in whole or in part. The beam 156 and the slide member 154 are threaded so that they mesh with each other. By configuring the scale 150 in this way, as shown in FIG. 7B and the schematic diagram of the end surface along the chain line DD′ (FIG. 7C), the slide member 154 can be slid along the x-direction by rotating the slide member 154 around the x-direction (see the dotted arrow in FIG. 7B).

[0035] Alternatively, as shown in Fig. 8, the scale 150 may be formed of a single member having a threaded outer surface. In this case, the outer surface of the scale 150 may be externally threaded, a through hole may be provided in a structure for connecting the scale 150 to the third cylindrical member (for example, a front plate 152), and the inner wall of the through hole may be internally threaded. With this structure, the scale 150 can be adjusted to any position relative to the third cylindrical member 130, and the positional relationship between the third cylindrical member 130 and the scale 150 at this position can be fixed.

[0036] The above-described embodiments of the present invention may be combined as appropriate as long as they are not mutually inconsistent. Furthermore, those in which a person skilled in the art appropriately adds or deletes components or modifies the design based on each embodiment are also included in the scope of the present invention as long as they include the gist of the present invention.

[0037] Furthermore, even if there are other effects and advantages different from those brought about by the respective embodiments described above, those which are clear from the description in this specification or which can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention. [Explanation of symbols]

[0038] 100: tension balancer, 102: first hook, 104: second hook, 106: hanger hook, 110: first cylindrical member, 112: first coil spring, 114: first front washer, 120: second cylindrical member, 122: second coil spring, 124: first rear washer, 126: second front washer, 130: third cylindrical member, 132: second rear washer, 134: second back plate , 140: first back plate, 142: U-shaped bar, 144: collar, 146: guide plate, 150: scale, 152: front plate, 154: slide member, 154a: through hole, 154b: through hole, 156: beam, 156a: through hole, 156b: slit, 156c: convex portion, 156d: concave portion, 158: bolt, 160: nut, 162: washer, 170: pointer member

Claims

1. Cylindrical members from the first to the nth, The first to (n-1) coil springs, The first hook attached to the first cylindrical member, A second hook attached to the aforementioned cylindrical member n, and Attached to the n cylindrical member, extending in a first direction parallel to the central axis of the first to n cylindrical members, located outside the n cylindrical member, overlapping with the n cylindrical member in a second direction perpendicular to the first direction, and comprising a scale that is expandable and contractible in the first direction, The first to nth cylindrical members are arranged such that the (j+1)th cylindrical member selected from the first to nth cylindrical members is surrounded by the jth cylindrical member selected from the first to nth cylindrical members, The first to nth cylindrical members and the first to (n-1)th coil springs are arranged alternately with each other. A tension balancer where n is a natural number greater than or equal to 2, and j is a variable selected from natural numbers between 1 and (n-1).

2. The device further comprises a guide member extending in the second direction, The tension balancer according to claim 1, wherein the scale is disposed between the pointer member and the first cylindrical member.

3. The aforementioned scale is A beam connected to the n cylindrical member and extending in the first direction, and The tension balancer according to claim 1, comprising a sliding member that houses the beam, is slidable along the beam, and has memory.

4. The beam has a plurality of through holes arranged in the first direction, The tension balancer according to claim 3, wherein the sliding member has at least one opening that overlaps with one of the through holes.

5. The beam has a slit that extends in the first direction and penetrates the beam, The tension balancer according to claim 3, wherein the sliding member has at least one opening that overlaps with the slit.

6. The tension balancer according to claim 5, wherein the width of the slit changes periodically.

7. The tension balancer according to claim 3, wherein the end face shape of the beam in a plane perpendicular to the first direction is circular.

8. The aforementioned beam is plate-shaped, The tension balancer according to claim 3, wherein the end face of the slide member in a plane perpendicular to the first direction is C-shaped.

9. The outer circumference of the beam has a threaded surface, The tension balancer according to claim 3, wherein the slide member has an internally threaded inner wall and a bottomed hole or through hole extending in the first direction.

10. The scale is connected to the n cylindrical member by a front plate having a female threaded through hole, The tension balancer according to claim 3, wherein the sliding member has a surface with male threads.

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