Elastic body and torque sensor

Abstract

To provide an elastic body and a torque sensor which can be manufactured at low cost.SOLUTION: The elastic body includes a first structure in which a plurality of plate-shaped horizontal plate portions extending in a direction along an arbitrary reference plane and a plurality of plate-shaped vertical plate portions extending in a direction intersecting the reference plane are annularly arranged and connected along the reference plane, a second structure which is located inside the first structure and in which the plurality of horizontal plate portions and the plurality of vertical plate portions are annularly arranged and connected along the reference plane, and a plurality of plate-shaped third structures which connect the vertical plate portions of the first structure and the second structure to each other and extend on an extension of the vertical plate portions.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an elastic body and a torque sensor. [Background technology]

[0002] Patent Document 1 discloses a drive device having an elastic body arranged on the output side of a reducer. The elastic body is a member used to detect torque. The elastic body has an outer ring fixed to a base member, an inner ring which is an example of a third portion, and a plurality of leaf springs which are an example of an elastic portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7146609 Summary of the Invention [Problem to be solved by the invention]

[0004] A torque sensor is provided, for example, in a joint of a robot arm to detect torque caused by the rotation of the joint, etc. For this reason, an elastic body that elastically deforms when subjected to torque is used for the torque sensor, but the elastic body described in Patent Document 1 requires welding or cutting at multiple locations during manufacturing, which increases the cost.

[0005] Therefore, an object of the present disclosure is to provide an elastic body and a torque sensor that can be manufactured at low cost. [Means for solving the problem]

[0006] One aspect of the elastic body according to the present disclosure comprises a first structure in which a plurality of plate-shaped horizontal plate portions extending in a direction along an arbitrary reference plane and a plurality of plate-shaped vertical plate portions extending in a direction intersecting the reference plane are arranged in a ring shape along the reference plane, a second structure located inside the first structure in which a plurality of the horizontal plate portions and a plurality of the vertical plate portions are arranged in a ring shape along the reference plane, and a plurality of plate-shaped third structures extending in extensions of the vertical plate portions and connecting the vertical plate portions of the first structure and the second structure.

[0007] Furthermore, one aspect of the torque sensor according to the present disclosure includes the elastic body and a strain body located between the first structure and the second structure for detecting relative displacement between the first structure and the second structure. [Effects of the Invention]

[0008] The elastic body and torque sensor of the present disclosure can be manufactured at low cost. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing the configuration of a torque sensor according to the first embodiment. [Figure 2] FIG. 2 is a perspective view showing the mounting structure of the torque sensor. [Figure 3] FIG. 3 is a cross-sectional view showing the mounting structure of the torque sensor. [Figure 4] FIG. 4 is a perspective view showing a metal material of the elastic body in the first embodiment. [Figure 5] FIG. 5 is a partially enlarged view showing the metal material of the elastic body in the first embodiment. [Figure 6] FIG. 6 is a perspective view showing a modified example of the torque sensor. [Figure 7] FIG. 7 is a partially enlarged view showing a modified example of the torque sensor. [Figure 8] FIG. 8 is a diagram showing a modified example of the elastic body. [Figure 9] FIG. 9 is a diagram showing a torque sensor according to the second embodiment. [Figure 10] FIG. 10 is a perspective view showing a part of the metallic material of the elastic body in the second embodiment. [Figure 11] FIG. 11 is a plan view showing a part of the metallic material of the elastic body in the second embodiment. [Figure 12] FIG. 12 is a diagram showing a torque sensor according to the third embodiment. [Figure 13] FIG. 13 is a diagram showing a mounting structure of a torque sensor according to the third embodiment. [Figure 14] FIG. 14 is a perspective view showing a metallic material of the elastic body in the third embodiment. [Figure 15] FIG. 15 is a partially enlarged view showing the metallic material of the elastic body in the third embodiment. [Figure 16] FIG. 16 is a diagram showing a torque sensor according to the fourth embodiment. [Figure 17] FIG. 17 is a perspective view showing a part of the metallic material of the elastic body in the fourth embodiment. [Figure 18] FIG. 18 is a plan view showing a part of the metallic material of the elastic body in the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the elastic body and torque sensor of the present disclosure will be described in detail with reference to the accompanying drawings. However, to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art, more detailed description than necessary may be omitted. For example, detailed description of already well-known matters or redundant description of substantially identical configurations may be omitted. Furthermore, elements shown in earlier-described figures may be appropriately referenced in the description of later figures.

[0011] First Embodiment FIG. 1 is a diagram showing the configuration of a torque sensor 100 according to the first embodiment. The torque sensor 100 includes an elastic body 101 and a strain gauge 102 . The elastic body 101 has a ring-shaped structure and is formed, for example, by bending a plate-shaped metal material. In FIG. 1, XYZ coordinates are shown as a reference for directions for explanation. The Z-axis direction indicates the direction in which the central axis of the elastic body 101 extends, and the XY plane defined by the X-axis and Y-axis corresponds to an example of a reference plane in this disclosure. The XY plane is a plane perpendicular to the Z-axis. Note that the XYZ coordinates indicate a reference for directions, and the position of the origin has no particular significance. For this reason, in the following figures, the XYZ coordinates may be shown at a position away from the center of the elastic body 101 for convenience of illustration.

[0012] Torque sensor 100 is a sensor for detecting torque of Z-axis moment Mz with the central axis of elastic body 101 as the axis of rotation. Torque sensor 100 is mounted on, for example, a robot to detect the rotational torque of the robot's joints. The strain gauge 102 corresponds to an example of a strain gauge in the present disclosure, and electrically detects the strain of the elastic body 101 caused by the torque of the Z-axis moment Mz. That is, the strain gauge 102 generates an electrical displacement when deformed. The strain gauge 102 may be any type that generates an electrically detectable displacement. For example, the strain gauge 102 may change electrical resistance or generate a voltage depending on the amount of deformation. The torque sensor 100 detects torque by outputting these electrical displacements from the strain gauge 102. Note that the strain gauge may be provided with a member whose displacement or strain can be optically detected.

[0013] The elastic body 101 includes an annular first structure 110, an annular second structure 120, and a plurality of plate-like third structures . The first structure 110 has an annular shape that rotates on a plane parallel to the XY plane. The second structure 120 has an annular shape that rotates on a plane parallel to the XY plane inside the first structure 110. The first structure 110 and the second structure 120 are each annular, for example, and are positioned concentrically with each other, for example.

[0014] The plurality of third structures 130 are arranged radially between the first structure 110 and the second structure 120, and connect the first structure 110 and the second structure 120 to each other. The strain gauge 102 is located between the first structure 110 and the second structure 120, and detects the relative displacement between the first structure 110 and the second structure 120. Any number of strain gauges 102 may be provided, but it is preferable that a plurality of strain gauges 102 are provided symmetrically with respect to the central axes of the first structure 110 and the second structure 120. In FIG. 1, two strain gauges 102 are provided as an example.

[0015] The first structure 110 and the second structure 120 each have a structure in which a plurality of horizontal plate portions 111, 121 and a plurality of vertical plate portions 112, 122 are alternately arranged and connected in a ring shape. The horizontal plate portions 111, 121 are plate-like portions that extend along the XY plane, and the vertical plate portions 112, 122 are plate-like portions that extend along the Z-axis direction. As an example, the multiple vertical plate portions 112, 122 are arranged radially with respect to the central axis of the ring shape of the elastic body 101, and the surfaces of the vertical plate portions 112, 122 extend in radial directions from the central axis and in the direction in which the central axis extends.

[0016] That is, the first structure 110 has a plurality of horizontal plate portions 111 that extend in a direction along the reference plane and a plurality of vertical plate portions 112 that extend in a direction intersecting the reference plane, which are lined up in a ring shape along the reference plane. The second structure 120 is located inside the first structure 110, and has a plurality of horizontal plate portions 121 and a plurality of vertical plate portions 122 that are lined up in a ring shape along the reference plane and are connected.

[0017] The plurality of plate-like third structures 130 connect the vertical plate portions 112, 122 of the first structure 110 and the second structure 120 to each other, and extend along the extensions of the vertical plate portions 112, 122. Therefore, as an example, the multiple third structures 130 are arranged radially with respect to the central axis of the annular shape of the elastic body 101, and the surfaces of the third structures 130 are on the same plane as the vertical plate portions 112, 122 and extend in the radial direction from the central axis and along the direction in which the central axis extends.

[0018] The vertical plate portions 112, 122 have a folded shape consisting of rising portions 112a, 122a, falling portions 112b, 122b, and folded portions 112c, 122c. The rising portions 112a, 122a extend along the Z-axis direction from one of two horizontal plate portions 111, 121 that are adjacent in the circumferential direction of the first structure 110 and the second structure 120. The falling portions 112b, 122b extend in the -Z-axis direction and connect to the other of the two horizontal plate portions 111, 121. The folded portions 112c, 122c fold back from the Z-axis direction to the -Z-axis direction.

[0019] That is, the vertical plate portions 112, 122 extend in the Z direction intersecting the reference plane, turn back, and extend in the -Z direction opposite to the Z direction. Because the vertical plate portions 112, 122 have a turned back shape, the multiple horizontal plate portions 111, 121 can be arranged on the same plane. In the folded vertical plate portions 112, 122, the rising portions 112a, 122a and the falling portions 112b, 122b are arranged radially with respect to the central axis of the annular shape of the elastic body 101, and the surfaces of the rising portions 112a, 122a and the falling portions 112b, 122b extend in the radial direction from the central axis and along the direction in which the central axis extends. Furthermore, the vertical plate portions 112, 122 connect the ends of two horizontal plate portions 111, 121 that are adjacent in the circumferential direction of the first structure 110 and the second structure 120, which are located closer to each other in the circumferential direction.

[0020] 2 and 3 are diagrams showing the mounting structure of the torque sensor 100. Fig. 2 shows a perspective view, and Fig. 3 shows a cross-sectional view. The torque sensor 100 is mounted such that one of the first structure 110 and the second structure 120 of the elastic body 101 is mounted to a load that receives torque, and the other is mounted to a power source that generates torque. The power source side is the torque input side, and the load side is the torque output side.

[0021] 2 and 3, the second structure 120 is fixed to an input-side structure 210. The structure 210 is, for example, a part of a motor or a reducer. The first structure 110 is fixed to an output-side structure 220. The structure 220 is, for example, a part of a movable part such as a hand or arm of a robot.

[0022] The first structure 110 and the second structure 120 have a plurality of horizontal plate portions 111, 121 arranged on the same plane, which are fixed to the input-side and output-side structures 210, 220 by, for example, screwing. By fixing in this manner, the first structure 110 and the second structure 120 are integrated with the input-side and output-side structures 210, 220, and obtain rigidity.

[0023] The elastic body 101 of the torque sensor 100 includes a beam structure 140 that connects the vertical plate portion 112 of the first structure 110, the vertical plate portion 122 of the second structure 120, and the third structure 130. The multiple beam structures 140 are arranged radially along the annular structure of the elastic body 101, and these beam structures 140 suppress distortions other than the Z-axis moment Mz.

[0024] That is, the radial beam structure 140 suppresses distortion caused by the X-axis moment Mx and the Y-axis moment Yx due to rotation about the X-axis and the Y-axis, respectively, and by forces Fx, Fy, and Fz in the directions of the X-axis, Y-axis, and Z-axis, respectively. Beam structure 140 has notch portion 141. That is, third structure 130 separates first structure 110 and second structure 120 at the folded-back portions of vertical plate portions 112, 122. Providing notch portion 141 makes it easier for mutual rotation around the Z axis to occur between first structure 110 and second structure 120 due to the torque of Z-axis moment Mz, making it easier to detect the torque using strain gauge 102.

[0025] As described above, the elastic body 101 of the torque sensor 100 can be formed by bending a plate-shaped metal material. 4 and 5 are diagrams showing the metal material 105 of the elastic body 101. Fig. 4 shows a perspective view, and Fig. 5 shows a partially enlarged view.

[0026] The metal material 105 is a band-shaped metal plate that extends in an annular shape, and is bent to form the elastic body 101 shown in Fig. 1. Specifically, for example, the metal material 105 is press-processed, and then further post-processing is performed on the portions where processing precision is insufficient, thereby forming the elastic body 101.

[0027] Metal material 105 has a first edge 151, a second edge 152, and a plurality of connecting portions 153. First edge 151 is an annular portion along one edge of the band of metal material 105, and second edge 152 is an annular portion along the other edge of the band of metal material 105. Second edge 152 is located more inward than first edge 151, so the ring of second edge 152 is smaller than the ring of first edge 151.

[0028] The multiple connecting portions 153 connect the first edge portion 151 and the second edge portion 152 at multiple discrete locations along the band of metal material 105. In the first embodiment, two connecting portions 153 connect the first edge portion 151 and the second edge portion 152 at each location. The open portion between the first edge portion 151 and the second edge portion 152 that is not connected by the connecting portions 153 forms an opening 154.

[0029] 4 and 5, mountain folds are indicated by dashed lines and valley folds are indicated by chain lines. Elastic body 101 is formed by subjecting metal material 105 to a process in which a series of valley folds, mountain folds, valley folds, valley folds, mountain folds, and valley folds are repeated in a circular pattern. That is, in the area sandwiched between the valley folds indicated by the dashed and dotted lines, the outer circumferential side becomes the horizontal plate portion 111 of the first structure 110, and the inner circumferential side becomes the horizontal plate portion 121 of the second structure 120. In addition, in the area sandwiched between the valley folds indicated by the dashed and dotted lines and the mountain folds indicated by the broken lines, the outermost circumferential side becomes the vertical plate portion 112 of the first structure 110, and the innermost circumferential side becomes the vertical plate portion 122 of the second structure 120, and the area between them becomes the third structure 130.

[0030] In other words, by bending the metal material 105, the connection portion 153 becomes the third structure 130, and the connection points of the first edge portion 151 and the second edge portion 152 connected by the connection portion 153 become the vertical plate portions 112 and 122. Furthermore, the open areas of the first edge portion 151 and the second edge portion 152 other than the connection points (i.e., the areas adjacent to the opening 154) become the horizontal plate portions 111 and 121. As a result of bending the metal material 105, the connection points that become the vertical plate portions 112 and 122 stand in, for example, the Z direction that intersects with the open areas that become the horizontal plate portions 111 and 121, and the open areas spread out along the reference plane.

[0031] By forming the elastic body 101 by bending the metal material 105 in this way, the elastic body 101 and the torque sensor 100 can be manufactured inexpensively and in a short period of time. 6 and 7 are diagrams showing modified examples of the torque sensor 100. Fig. 6 shows a perspective view, and Fig. 7 shows a partially enlarged view.

[0032] 6 and 7, the torque sensor 100 has strain gauges 102 on the side surfaces of a beam structure 140. In this case, the strain gauges 102 may be foil strain gauges, for example. In the torque sensor 100 of the modified example, strain gauges 102 are provided on both side surfaces of one beam structure 140, and further, strain gauges 102 are provided on each of the beam structures 140 positioned symmetrically in, for example, four directions with respect to the annular elastic body 101. In other words, the torque sensor 100 of the modified example is provided with a total of eight strain gauges 102, including those hidden by the beam structures 140 in FIG. Foil strain gauges and the like only output one detection signal that indicates the magnitude of the strain, and cannot detect the direction of the strain. By symmetrically arranging multiple strain gauges 102 as described above, it becomes possible to cancel out strain components other than the Z-axis moment Mz and detect torque around the Z axis.

[0033] FIG. 8 is a diagram showing a modified example of the elastic body 101. In FIG. The elastic body 101 of this modified example does not have the notch 141 in the beam structure 140. The elastic body 101 of this modified example has higher rigidity around the Z axis than when the elastic body 101 has the notch 141, and can withstand large torque. Therefore, it is possible to detect torque in large devices, powerful motors, etc.

[0034] <Other embodiments> Next, another embodiment different from the above-described first embodiment will be described. In the following description, duplicated explanations of elements that are the same as elements that have already been described will be omitted.

[0035] Fig. 9 is a diagram showing a torque sensor 200 according to the second embodiment, and Fig. 10 and Fig. 11 are diagrams showing a part of a metal material 205 of an elastic body 201 according to the second embodiment. Fig. 10 shows a perspective view, and Fig. 11 shows a plan view. The torque sensor 200 of the second embodiment includes an elastic body 201 and a strain gauge (not shown) similar to that of the first embodiment. In the elastic body 201 of the second embodiment, the height in the Z direction of the beam structure 140 is lower on the outer periphery side and higher on the inner periphery side. That is, the vertical plate portion 122 of the second structure 120 has a larger dimension in the direction intersecting with the reference plane than the vertical plate portion 112 of the first structure 110.

[0036] Since the vertical plate portion 122 of the second structure 120 is large, the elastic body 201 in the second embodiment can be formed from a strip-shaped metal material 205 that extends linearly, as shown in FIGS. Metal material 205 has a first edge 251, a second edge 252, and a plurality of connecting portions 253. First edge 251 is a linear portion along one edge of the band of metal material 205, and second edge 252 is a linear portion along the other edge of the band of metal material 205. The plurality of connecting portions 253 connect first edge 251 and second edge 252 at a plurality of discrete locations along the band of metal material 205. The open portions between first edge 251 and second edge 252 that are not connected by connecting portions 253 form openings 254. A band-shaped metal material 205 is repeatedly folded in the form of valley folds shown by dashed lines, mountain folds shown by broken lines, valley folds, valley folds, mountain folds, and valley folds to form a ring-shaped elastic body 201.

[0037] As a result of the folding, at the location sandwiched between the valley folds indicated by the dashed and dotted lines, the outer circumferential side becomes horizontal plate portion 111 of first structure 110, and the inner circumferential side becomes horizontal plate portion 121 of second structure 120. Furthermore, at the location sandwiched between the valley folds indicated by the dashed and dotted lines and the mountain folds indicated by the broken lines, the outermost circumferential side becomes vertical plate portion 112 of first structure 110, and the innermost circumferential side becomes vertical plate portion 122 of second structure 120, and the space between them becomes third structure 130.

[0038] In other words, by bending the metal material 205, the connection portion 253 becomes the third structure 130, and the connection points of the first edge portion 251 and the second edge portion 252 connected by the connection portion 253 become the vertical plate portions 112 and 122. Furthermore, the open areas of the first edge portion 251 and the second edge portion 252 other than the connection points (i.e., the areas adjacent to the opening 254) become the horizontal plate portions 111 and 121. As a result of bending the metal material 205, the connection points that become the vertical plate portions 112 and 122 stand in a direction that intersects with the open areas that become the horizontal plate portions 111 and 121, and the open areas spread out along the reference plane.

[0039] In the second embodiment, the two valley folds sandwiching the mountain fold are inclined so as to open downward in FIG. 11. The total length of the horizontal plate portion 111 and the vertical plate portion 112 that form the first structure 110 is equal to the total length of the horizontal plate portion 121 and the vertical plate portion 122 that form the second structure 120. In other words, the lengths of the first edge portion 251 and the second edge portion 252 are equal. This makes it possible to form the annular elastic body 201 using a strip-shaped metal material 205 that extends linearly. The use of the linear metal material 205 improves material utilization efficiency, further reducing costs.

[0040] FIG. 12 is a diagram showing a torque sensor 300 according to the third embodiment. The torque sensor 300 of the third embodiment includes an elastic body 301 and a strain gauge 102. The elastic body 301 of the third embodiment includes an annular first structure 310, an annular second structure 320, and a plurality of plate-like third structures 330.

[0041] In the third embodiment, the first structure 310 and the second structure 320 each have a structure in which a plurality of horizontal plate portions 111, 121 and a plurality of vertical plate portions 112, 122 are alternately arranged and connected in an annular shape. Furthermore, a plurality of plate-like third structures 330 connect the vertical plate portions 112, 122 of the first structure 310 and the second structure 320 to each other, and extend along the extensions of the vertical plate portions 112, 122. Furthermore, the vertical plate portions 112 of the first structure 310, the vertical plate portions 122 of the second structure 320, and the third structure 330 are connected to form a beam structure 340.

[0042] In the third embodiment, the vertical plate portions 112, 122 do not have a folded shape. That is, the vertical plate portions 112, 122 extend, for example, in the Z direction intersecting the reference plane, with one end connected to a horizontal plate portion 111, 121 and the other end connected to another horizontal plate portion 111, 121. Therefore, the positions of the multiple horizontal plate portions 111, 121 in the Z direction are alternately different in annular arrangement. In other words, the positions of the odd-numbered and even-numbered horizontal plate portions 111, 121 in the Z direction are different in annular arrangement.

[0043] In the third embodiment, the multiple vertical plate portions 112, 122 are also arranged radially with respect to the central axis of the annular shape of the elastic body 301, and the surfaces of the vertical plate portions 112, 122 extend in radial directions from the central axis and in the direction in which the central axis extends. The multiple third structures 330 are also arranged radially with respect to the central axis of the annular shape of the elastic body 301, and the surfaces of the third structures 330 are on the same plane as the vertical plate portions 112, 122 and extend in radial directions from the central axis and in the direction in which the central axis extends. Furthermore, the vertical plate portions 112, 122 connect the ends of two horizontal plate portions 111, 121 that are adjacent in the circumferential direction of the first structure 310 and the second structure 320, which are located closer to each other in the circumferential direction.

[0044] FIG. 13 is a diagram showing an attachment structure of a torque sensor 300 according to the third embodiment. In the torque sensor 300 of the third embodiment, the input-side structure 210 and the output-side structure 220 can be fixed to the first structure 310 and the second structure 320 from both sides of the torque sensor 300. Therefore, the torque sensor 300 of the third embodiment has a higher degree of freedom in terms of installation structure than the first and second embodiments.

[0045] 14 and 15 are diagrams showing the metal material 305 of the elastic body 301 in the third embodiment. Fig. 14 shows a perspective view, and Fig. 15 shows a partially enlarged view. The metal material 305 in the third embodiment is a band-shaped metal plate extending in an annular shape, and is bent to form the elastic body 301 shown in FIG.

[0046] Metal material 305 has a first edge 351, a second edge 352, and multiple connecting portions 353. First edge 351 is an annular portion along one edge of the band of metal material 305, and second edge 352 is an annular portion along the other edge of the band of metal material 305. Second edge 352 is located more inward than first edge 351, so the ring of second edge 352 is smaller than the ring of first edge 351. A plurality of connectors 353 connect first edge 351 and second edge 352 at a plurality of discrete locations along the band of metal material 305. The open portions between first edge 351 and second edge 352 that are not connected by connectors 353 form openings 354.

[0047] In the third embodiment, metal material 305 is subjected to a process of repeating mountain folds indicated by dashed lines and valley folds indicated by chain lines, valley folds, mountain folds, mountain folds, valley folds, valley folds, and mountain folds in a circular pattern to form elastic body 301. That is, at the locations sandwiched between the mountain folds and the valley folds, the outer circumferential sides become horizontal plate portion 111 of first structure 110, and the inner circumferential sides become horizontal plate portion 121 of second structure 120.

[0048] Furthermore, in the area sandwiched between the valley fold and the mountain fold, the outermost side becomes the vertical plate portion 112 of the first structure 110, and the innermost side becomes the vertical plate portion 122 of the second structure 120, and the area between them becomes the third structure 330. In other words, by bending the metal material 305, the connection portion 353 becomes the third structure 330, and the connection points of the first edge portion 351 and the second edge portion 352 connected by the connection portion 353 become the vertical plate portions 112 and 122. Furthermore, the open portions of the first edge portion 351 and the second edge portion 352 other than the connection points (i.e., the portions adjacent to the opening 354) become the horizontal plate portions 111 and 121. As a result of bending the metal material 305, the connection points that become the vertical plate portions 112 and 122 stand in, for example, the Z direction intersecting with the open portions that become the horizontal plate portions 111 and 121, and the open portions spread out along the reference plane. However, the odd-numbered open portions and the even-numbered open portions have different heights in the Z direction. In this way, in the third embodiment as well, the elastic body 301 can be formed by bending the metal material 305, so that the elastic body 301 and the torque sensor 300 can be manufactured inexpensively and in a short period of time.

[0049] Fig. 16 is a diagram showing a torque sensor 400 of the fourth embodiment, and Fig. 17 and Fig. 18 are diagrams showing a part of a metal material 405 of an elastic body 401 in the fourth embodiment. Fig. 17 shows a perspective view, and Fig. 18 shows a plan view. The torque sensor 400 of the fourth embodiment includes an elastic body 401 and a strain gauge (not shown) similar to that of the first embodiment.

[0050] In the elastic body 401 of the fourth embodiment, the height of the beam structure 340 in the Z direction is lower on the outer periphery side and higher on the inner periphery side, as in the second embodiment. That is, the Z direction dimension of the vertical plate portions 112, 122 of the first structure 110 is smaller than the vertical plate portion 122 of the second structure 120.

[0051] In addition, in the fourth embodiment, half of the multiple horizontal plate portions 111, 121 are inclined with respect to the XY plane, and therefore, for example, an attachment protrusion 402 is provided on the horizontal plate portion 121 of the second structure 320 in order to attach it to a planar structure. Since the vertical plate portion 122 of the second structure 320 is large, the elastic body 401 in the fourth embodiment can be formed from a strip-shaped metal material 405 that extends linearly, as shown in FIGS.

[0052] The metal material 405 has a first edge 451, a second edge 452, and a plurality of connecting portions 453. The first edge 451 is a linear portion along one edge of the band of metal material 405, and the second edge 452 is a linear portion along the other edge of the band of metal material 405. The plurality of connecting portions 453 connect the first edge 451 and the second edge 452 at a plurality of discrete locations along the band of metal material 405. The open portions between the first edge 451 and the second edge 452 that are not connected by the connecting portions 453 form openings 454. A strip-shaped metal material 405 is repeatedly folded in the form of valley folds shown by dotted lines, mountain folds shown by dashed lines, mountain folds, valley folds, valley folds, mountain folds, mountain folds, and valley folds to form a ring-shaped elastic body 401.

[0053] In the fourth embodiment, at the locations sandwiched between mountain folds and between valley folds, the outer peripheral side becomes the horizontal plate portion 111 of the first structure 310, and the inner peripheral side becomes the horizontal plate portion 121 of the second structure 320. Furthermore, in the area sandwiched between the valley fold and the mountain fold, the outermost side becomes the vertical plate portion 112 of the first structure 310, the innermost side becomes the vertical plate portion 122 of the second structure 320, and the area between them becomes the third structure 330.

[0054] In other words, by bending the metal material 405, the connection portion 453 becomes the third structure 330, and the connection points of the first edge portion 451 and the second edge portion 452 connected by the connection portion 453 become the vertical plate portions 112 and 122. Furthermore, the open areas of the first edge portion 451 and the second edge portion 452 other than the connection points (i.e., the areas adjacent to the opening 454) become the horizontal plate portions 111 and 121. As a result of bending the metal material 405, the connection points that become the vertical plate portions 112 and 122 stand in a direction that intersects with the open areas that become the horizontal plate portions 111 and 121, and the open areas spread out along the reference plane. However, the odd-numbered open areas and the even-numbered open areas have different heights in the Z direction.

[0055] In the fourth embodiment, the mountain folds and valley folds are inclined so as to open downward in FIG. 18, and the mountain folds and valley folds are inclined so as to open upward in FIG. 18. The total length of the horizontal plate portion 111 and the vertical plate portion 112 that form the first structure 110 is equal to the total length of the horizontal plate portion 121 and the vertical plate portion 122 that form the second structure 120. This makes it possible to form the annular elastic body 401 using a strip-shaped metal material 405 that extends linearly. The use of the linear metal material 405 improves the efficiency of material utilization and further reduces costs.

[0056] In the above, metal members extending in a straight line and metal members extending in a ring shape are presented, but the metal members used to form the elastic member are not limited to the above, and may be, for example, metal members extending in an arc shape that is not closed, or metal members extending in a wavy, serpentine shape. Furthermore, although the above provides an example of a method of using the elastic body and torque sensor of the present disclosure for detecting torque in a robot, the elastic body and torque sensor of the present disclosure are not limited to the above-described method of use and can be used in a wide range of applications, such as detecting torque in the steering and drive shafts of automobiles, detecting torque in the rotating shafts of motors and pumps, and detecting torque in the gear shafts of electrically assisted bicycles.

[0057] Furthermore, the above-described embodiments should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the above-described embodiments, and is intended to include all modifications within the meaning and scope of the claims. The present technology can be configured as follows.

[0058] (1) a first structure in which a plurality of horizontal plate portions extending in a direction along an arbitrary reference plane and a plurality of vertical plate portions extending in a direction intersecting the reference plane are arranged in a ring shape along the reference plane; a second structure located inside the first structure, in which a plurality of the horizontal plate portions and a plurality of the vertical plate portions are connected in a ring shape along the reference plane; a plurality of plate-shaped third structures extending along extensions of the vertical plate portions and connecting the vertical plate portions of the first structure and the second structure; An elastic body comprising:

[0059] (2) The elastic body according to (1), wherein the vertical plate portion of the second structure has a larger dimension in a direction intersecting with the reference plane than the vertical plate portion of the first structure. (3) 3. The elastic body according to claim 1, wherein the vertical plate portion has a shape that extends in a first direction intersecting with the reference plane, turns back, and extends in a direction opposite to the first direction.

[0060] (4) The vertical plate portion connects the ends of two adjacent horizontal plate portions in a circular arrangement, the ends being closer to each other in the circular arrangement, the third structure extending in the same plane as a rising portion of the vertical plate portion extending in the first direction, and the third structure extending in the same plane as a falling portion of the vertical plate portion extending in a direction opposite to the first direction, the rising portion, the falling portion, and the third structure extend in both a direction intersecting the reference plane and a direction approaching and separating from a center of the annular shape, The elastic body according to (3), wherein the folded portion of the vertical plate portion connects the ends of the rising portion and the falling portion opposite to the horizontal plate portion.

[0061] (5) The elastic body according to (3), wherein the third structure releases the first structure and the second structure at the folded-back portion of the vertical plate portion. (6) The elastic body described in (1) or (2) has a vertical plate portion extending in a first direction intersecting the reference plane, one end connected to the horizontal plate portion, and the other end connected to another horizontal plate portion. (7) The vertical plate portion connects the ends of two adjacent horizontal plate portions in a circular arrangement, the ends being closer to each other in the circular arrangement, The vertical plate portion of the first structure, the vertical plate portion of the second structure, and the third structure extend on the same plane in both a direction intersecting the reference plane and a direction approaching and separating from the center of the annular shape.

[0062] (8) The elastic body according to any one of (1) to (7), a strain-generating body positioned between the first structure and the second structure, for detecting relative displacement between the first structure and the second structure; (9) preparing a metal member in the shape of a strip extending in a straight or curved line, the metal member having a first edge along one edge of the strip, a second edge along the other edge of the strip, and a plurality of connecting portions connecting the first edge and the second edge at a plurality of discrete locations along the strip; bending the metal member to form a shape in which connection points of the first edge portion and the second edge portion connected by the connection portion stand in a direction intersecting with open areas other than the connection points, and the open areas extend along an arbitrary reference plane; A method for manufacturing an elastic member having the above structure. [Explanation of symbols]

[0063] 100, 200, 300, 400: Torque sensor 101, 201, 301, 401: Elastic body 102: Strain gauge 105, 205, 305, 405: Metal materials 110, 310: First structure 120, 320: Second structure 130, 330: Third structure 111, 121: Horizontal plate part 112, 122: Vertical plate section 112a, 122a: Rising part 112b, 122b: Falling 112c, 122c: Folded section 140:Beam structure 141: Notch 210: Input structure 220: Output structure

Claims

1. a first structure in which a plurality of horizontal plate portions extending in a direction along an arbitrary reference plane and a plurality of vertical plate portions extending in a direction intersecting the reference plane are arranged in a ring shape along the reference plane; a second structure positioned inside the first structure, in which a plurality of the horizontal plate portions and a plurality of the vertical plate portions are connected in a ring shape along the reference plane; a plurality of plate-like third structures extending along extensions of the vertical plate portions and connecting the vertical plate portions of the first structure and the second structure; An elastic body comprising:

2. The elastic body according to claim 1 , wherein the vertical plate portion of the second structure has a dimension larger than that of the vertical plate portion of the first structure in a direction intersecting the reference plane.

3. The elastic body described in claim 1, wherein the vertical plate portion extends from one end connected to the horizontal plate portion in a first direction intersecting the reference plane, folds back, extends in a direction opposite to the first direction, and connects to another horizontal plate portion.

4. The vertical plate portion connects end portions of two of the horizontal plate portions that are adjacent to each other in the annular arrangement, the end portions being closer to each other in the annular arrangement, the third structure extending in the same plane as a rising portion of the vertical plate portion extending in the first direction, and the third structure extending in the same plane as a falling portion of the vertical plate portion extending in a direction opposite to the first direction, the rising portion, the falling portion, and the third structure extend in both a direction intersecting the reference plane and a direction approaching and separating from a center of the annular shape, The elastic body according to claim 3 , wherein the folded portion of the vertical plate portion connects the ends of the rising portion and the falling portion on the opposite side from the horizontal plate portion.

5. The elastic body according to claim 3 , wherein the third structure releases the first structure and the second structure at the folded-back portion of the vertical plate portion.

6. The elastic body according to claim 1 , wherein the vertical plate portion extends in a first direction intersecting with the reference plane, one end of the vertical plate portion is connected to the horizontal plate portion, and the other end of the vertical plate portion is connected to another horizontal plate portion.

7. The vertical plate portion connects end portions of two of the horizontal plate portions that are adjacent to each other in the annular arrangement, the end portions being closer to each other in the annular arrangement, The elastic body of claim 6, wherein the vertical plate portion of the first structure, the vertical plate portion of the second structure, and the third structure extend on the same plane in both a direction intersecting the reference plane and a direction approaching and separating from the center of the annular ring.

8. The elastic body according to any one of claims 1 to 7; a strain-generating body positioned between the first structure and the second structure, for detecting relative displacement between the first structure and the second structure.

9. preparing a metal member in the form of a strip extending in a straight or curved line, the metal member having a first edge along one edge of the strip, a second edge along the other edge of the strip, and a plurality of connecting portions connecting the first edge and the second edge at a plurality of discrete locations along the strip; bending the metal member to form a shape in which connection points of the first edge portion and the second edge portion connected by the connection portion stand in a direction intersecting with open areas other than the connection points, and the open areas extend along an arbitrary reference plane; A method for manufacturing an elastic member having the above structure.

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