Force sensor

Abstract

To provide a force sensor which can be improved in performance.SOLUTION: The force sensor includes: a first sensor body; a second sensor body; a strain body for connecting the first sensor body and the second sensor body to each other; a detection element; and a detection circuit. The strain body includes: a first displacement part; a second displacement part; an inclined structure body; a first connection part; and a second connection part. The inclined structure body includes: a pair of first inclined parts arranged on both sides of the first connection part in a second direction; and a pair of second inclined parts arranged on both sides of the second connection part in the second direction. The first displacement part is connected to the first inclined part arranged on one side of the first connection part in the second direction and the second displacement part is connected to the second inclined part arranged on the other side of the second connection part in the second direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a force sensor. [Background technology]

[0002] Force sensors that output a force acting in a specific axial direction and a moment (torque) acting around a specific rotation axis as an electrical signal have been known. Force sensors are widely used for force control of various robots, including industrial robots, collaborative robots, life support robots, medical robots, and service robots.

[0003] The force sensor is placed between the robot arm and the end effector (gripper, etc.) and detects the force acting on the workpiece. The detected force is used to control the robot. For example, if the robot arm comes into contact with a person, the force sensor detects the contact. This allows the operation of the robot arm to be stopped in an emergency.

[0004] With the expansion of the market in recent years, there is a demand for higher performance force sensors. More specifically, in a conventional capacitive force sensor (see, for example, Patent Document 1), an even number (for example, two) of capacitance elements are provided on one strain body. When a force Fz acts in the Z-axis direction (height direction of the force sensor), these capacitance elements uniformly increase or decrease. In this case, the output value of the force Fz becomes easily affected by disturbances such as noise or ambient temperature. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-135103 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above points, and has an object to provide a force sensor that can achieve high performance. [Means for solving the problem]

[0007] [1] This disclosure: a first sensor body that receives the force or moment to be detected; a second sensor body disposed at a position different from the first sensor body in a first direction; a strain generating body that connects the first sensor body and the second sensor body and is elastically deformed by the action of a force or moment applied to the first sensor body; A detection element for detecting a displacement caused by elastic deformation of the strain body; a detection circuit that outputs an electrical signal indicative of a force or moment acting on the first sensor body based on a detection result of the detection element; Equipped with the strain generating body includes a first displacement portion and a second displacement portion which are displaced in opposite directions in the first direction when the first sensor body receives a force in the first direction, the detection element includes a first capacitive element that detects a change in capacitance value due to displacement of one of the first displacement portion and the second displacement portion in the first direction, and a second capacitive element that detects a change in capacitance value due to displacement of the other of the first displacement portion and the second displacement portion in the first direction, the strain body includes a tilting structure disposed between the first sensor body and the second sensor body, a first connection portion connecting the first sensor body and the tilting structure, and a second connection portion connecting the second sensor body and the tilting structure, the tilting structure includes a pair of first tilting parts connected to the first connection part and arranged on both sides of the first connection part in a second direction perpendicular to the first direction, and a pair of second tilting parts connected to the second connection part and arranged on both sides of the second connection part in the second direction, the first displacement portion is connected to the first tilting portion disposed on one side in the second direction with respect to the first connection portion, The second displacement portion is connected to the second tilting portion arranged on the other side in the second direction with respect to the second connection portion. It may be a force sensor.

[0008] [2] This disclosure: The first displacement portion is disposed on a side of the other first tilting portion with respect to the corresponding first tilting portion, The second displacement portion is disposed on the side of the other second tilt portion with respect to the corresponding second tilt portion. The force sensor may be as described in [1].

[0009] [3] This disclosure: The first displacement portion is connected to the first tilt portion via a first arm portion, the first arm portion extends in a direction from the corresponding first tilting portion toward the other first tilting portion in the second direction, The second displacement portion is connected to the second tilt portion via a second arm portion, The second arm portion extends in a direction from the corresponding second tilting portion toward the other second tilting portion in the second direction. The force sensor may be as described in [2].

[0010] [4] This disclosure: the first arm portion is attached to a surface of the corresponding first tilting portion facing the first sensor body via a first connecting portion; The second arm portion is attached to a surface of the corresponding second tilting portion facing the second sensor body via a second connecting portion. The force sensor may be as described in [3].

[0011] [5] This disclosure: The first displacement portion and the second displacement portion are disposed on one side of the tilting structure in a third direction perpendicular to the first direction and the second direction. The force sensor may be any one of those described in [1] to [4].

[0012] [6] This disclosure: the tilting structure further includes a pair of first deformation parts connecting the corresponding first tilting parts to the first connection part, and a pair of second deformation parts connecting the corresponding second tilting parts to the second connection part, a dimension of the first deformation portion in the first direction is smaller than a dimension of the first tilt portion in the first direction; The dimension of the second deformation portion in the first direction is smaller than the dimension of the second tilting portion in the first direction. The force sensor may be any one of those described in [1] to [4].

[0013] [7] This disclosure: the first deformation portion includes a first opposing surface facing the first sensor body, the first opposing surface is disposed on a side of the second sensor body relative to a surface of the first tilting portion that faces the first sensor body, the second deformation portion includes a second opposing surface facing the second sensor body, the second opposing surface is disposed on the first sensor body side relative to a surface of the second tilting portion facing the second sensor body; The force sensor may be as described in [6].

[0014] [8] This disclosure: The first opposing surface and the second opposing surface are each formed in a curved shape. The force sensor may be as described in [7].

[0015] [9] This disclosure: the tilting structure further includes a pair of third deformation portions connecting the first tilting portion and the corresponding second tilting portion, a dimension of the third deformation portion in the second direction is smaller than a dimension of the first tilting portion in the second direction and smaller than a dimension of the second tilting portion in the second direction; The force sensor may be any one of the force sensors described in [6] to [8].

[0016]

[10] This disclosure relates to: The third deformation portion includes a curved third opposing surface opposing the other third deformation portion. The force sensor may be as described in [9].

[0017]

[11] This disclosure relates to: the first capacitance element includes a first displacement electrode substrate provided on one of the first displacement portion and the second displacement portion, and a first fixed electrode substrate facing the first displacement electrode substrate, the second capacitance element includes a second displacement electrode substrate provided on the other of the first displacement portion and the second displacement portion, and a second fixed electrode substrate facing the second displacement electrode substrate; The force sensor may be any one of those described in [1] to

[10] .

[0018]

[12] This disclosure relates to: the first fixed electrode substrate and the second fixed electrode substrate are supported by the second sensor body; The force sensor may be as described in

[11] .

[0019]

[13] This disclosure relates to: the first fixed electrode substrate and the second fixed electrode substrate are each supported by the second sensor body via a pedestal; The force sensor may be as described in

[11] or

[12] .

[0020]

[14] This disclosure relates to: The first sensor body and the second sensor body are connected by four of the strain bodies, The four flexure bodies include a first flexure body, a second flexure body, a third flexure body, and a fourth flexure body, The first direction is a Z-axis direction in an XYZ three-dimensional coordinate system, The first flexure body is disposed on the positive side of the Y axis direction with respect to the center of the first sensor body, the second flexure body is disposed on the negative side of the X axis direction with respect to the center of the first sensor body, the third flexure body is disposed on the negative side of the Y axis direction with respect to the center of the first sensor body, and the fourth flexure body is disposed on the positive side of the X axis direction with respect to the center of the first sensor body. The force sensor may be any one of those described in [1] to

[13] .

[0021]

[15] This disclosure relates to: The first displacement portion and the second displacement portion are disposed on a center side of the first sensor body with respect to the corresponding tilt structure. The force sensor may be as described in

[14] .

[0022]

[16] This disclosure relates to: a first sensor body that receives the force or moment to be detected; a second sensor body disposed at a position different from the first sensor body in a first direction; two strain bodies that connect the first sensor body and the second sensor body and are elastically deformed by the action of a force or moment applied to the first sensor body; A detection element for detecting a displacement caused by the elastic deformation of each of the strain bodies; a detection circuit that outputs an electrical signal indicative of a force or moment acting on the first sensor body based on a detection result of the detection element; Equipped with The two flexure bodies include a first flexure body and a second flexure body, the first strain body includes a first displacement portion that is displaced to one side in the first direction when the first sensor body receives a force in the first direction, the second strain generating body includes a second displacement portion that is displaced to the other side in the first direction when the first sensor body receives a force in the first direction, the detection element includes a first capacitive element that detects a change in capacitance value due to displacement of the first displacement section in the first direction, and a second capacitive element that detects a change in capacitance value due to displacement of the second displacement section in the first direction, each of the first and second strain bodies includes a tilting structure disposed between the first and second sensor bodies, a first connection portion connecting the first sensor body and the tilting structure, and a second connection portion connecting the second sensor body and the tilting structure; the tilting structure includes a pair of first tilting parts connected to the first connection part and arranged on both sides of the first connection part in a second direction perpendicular to the first direction, and a pair of second tilting parts connected to the second connection part and arranged on both sides of the second connection part in the second direction, The first displacement portion is connected to the first tilt portion of the first strain body, The second displacement portion is connected to the second tilting portion of the second strain body. It may be a force sensor.

[0023]

[17] This disclosure relates to: The first strain body includes two of the first displacement portions, one of the first displacement portions is connected to one of the first tilting portions of the first flexure body, and the other of the first displacement portions is connected to the other of the first tilting portions of the first flexure body; The second strain body includes two of the second displacement portions, One of the first displacement parts is connected to one of the second tilt parts of the second flexure body, and the other of the second displacement parts is connected to the other of the second tilt parts of the second flexure body. The force sensor may be as described in

[16] .

[0024]

[18] This disclosure relates to: The first direction is a Z-axis direction in an XYZ three-dimensional coordinate system, The first strain body is disposed on the positive side of the Y axis direction with respect to the center of the first sensor body, and the second strain body is disposed on the negative side of the Y axis direction with respect to the center of the first sensor body. The force sensor may be as described in

[16] or

[17] . Effect of the Invention

[0025] According to the present invention, high performance can be achieved. [Brief description of the drawings]

[0026] [Figure 1]FIG. 1 is a perspective view showing an example of a robot to which the force sensor according to the first embodiment is applied. [Diagram 2] FIG. 2 is a cross-sectional view showing the force sensor according to the first embodiment, and corresponds to a cross section taken along line AA in FIG. 3, which will be described later. [Diagram 3] FIG. 3 is a plan sectional view showing the force sensor of FIG. [Figure 4] FIG. 4 is a front view showing the first flexure body of FIG. [Diagram 5] FIG. 5 is a plan view showing the first flexure body of FIG. [Figure 6] FIG. 6 is a side view showing the first flexure body of FIG. [Figure 7] FIG. 7 is a planar development of the strain generating element of the force sensor shown in FIG. [Figure 8] FIG. 8 is a front view showing a schematic state of deformation of the flexure body of FIG. 4 when it is subjected to a force in the X-axis direction positive side. [Figure 9] FIG. 9 is a front view showing a schematic state of deformation of the flexure body of FIG. 4 when it is subjected to a force in the Y-axis direction positive side. [Figure 10A] FIG. 10A is a front view that illustrates a deformation state of the flexure body of FIG. 4 when it is subjected to a force in the positive Z-axis direction. [Figure 10B] FIG. 10B is a front view that illustrates a deformation state of the flexure body of FIG. 4 when the flexure body is subjected to a force in the negative Z-axis direction. [Figure 11] FIG. 11 is a table showing the change in the capacitance value of each capacitance element in the strain body of FIG. [Figure 12] FIG. 12 is a table showing changes in the capacitance value of each capacitance element in the force sensor of FIG. [Figure 13] FIG. 13 is a front view showing a modification of the flexure body of FIG. [Figure 14] FIG. 14 is a front view showing another modified example of the flexure body of FIG. [Figure 15] FIG. 15 is a plan sectional view showing another modified example of the force sensor of FIG. [Figure 16]FIG. 16 is a table showing changes in the capacitance value of each capacitance element in the force sensor of FIG. [Figure 17] FIG. 17 is a plan sectional view showing the force sensor according to the second embodiment. [Figure 18] FIG. 18 is a front view showing a schematic deformation state of the first strain body in FIG. 17 when a force in the Z-axis direction positive side is applied. [Figure 19] FIG. 19 is a front view showing a schematic deformation state of the second strain body in FIG. 17 when a force in the Z-axis direction positive side is applied. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to this specification, the scale and the aspect ratio are appropriately changed and exaggerated from those of the actual objects for the convenience of illustration and understanding.

[0028] The geometric conditions, physical characteristics, terms specifying the degree of the geometric conditions or physical characteristics, and numerical values ​​indicating the geometric conditions or physical characteristics used in this specification may be interpreted without being bound by their strict meaning. These geometric conditions, physical characteristics, terms, and numerical values ​​may be interpreted to include a range within which similar functions can be expected. Examples of terms specifying geometric conditions include "length," "angle," "shape," "parallel," "orthogonal," and "same."

[0029] (First embodiment) An individual force sensor according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 16. FIG.

[0030] First, a robot 1 according to the present embodiment will be described with reference to Fig. 1. Fig. 1 is a perspective view showing an example of a robot 1 according to the present embodiment. A force sensor 10 according to the present embodiment is attached to the robot 1. Examples of the robot 1 include various robots such as industrial robots, collaborative robots, life support robots, medical robots, and service robots. For convenience, the following description will be given taking an industrial robot to which the force sensor 10 is attached as an example.

[0031] 1, the industrial robot 1 includes a robot body 2, a tool 3, a force sensor 10, and a controller 5. The robot body 2 includes a robot arm 4. The robot arm 4 has a multi-joint arm structure.

[0032] A force sensor 10 is attached to the tip of the robot arm 4. More specifically, the force sensor 10 is attached between the robot arm 4 and the tool 3. The force sensor 10 is electrically connected to the controller 5 via an electric cable (not shown). Examples of the tool 3 include an end effector (gripper, etc.) and a tool changer (neither of which are shown), etc.

[0033] The controller 5 performs force control of the robot 1 based on the electrical signal output from the force sensor 10. In this way, the operations of the robot body 2 and the tool 3 are controlled.

[0034] Hereinafter, a force sensor 10 according to an embodiment of the present invention will be described with reference to Figs. 2 to 5. Fig. 2 is a cross-sectional view showing the force sensor according to this embodiment, and corresponds to the cross section taken along line AA in Fig. 3. Fig. 3 is a plan cross-sectional view showing the force sensor of Fig. 2. Fig. 4 is a front view showing the flexure body of Fig. 2. Fig. 5 is a plan view showing the flexure body of Fig. 4, and Fig. 6 is a side view showing the flexure body of Fig. 4. Fig. 7 is a planar development of the flexure body of the force sensor shown in Fig. 3.

[0035] In the following description, an XYZ three-dimensional coordinate system is defined, the Z-axis direction (first direction) is the up-down direction, and the force sensor 10 is arranged so that the force receiving body 20 is arranged on the upper side and the fixed body 25 is arranged on the lower side. For this reason, the force sensor 10 according to this embodiment is not limited to being used in a position in which the Z-axis direction is the up-down direction. Also, it is arbitrary whether the force receiving body 20 or the fixed body 25 is arranged on the upper side or the lower side.

[0036] The force sensor 10 has a function of outputting a force acting in a predetermined axial direction and a moment (torque) acting around a predetermined rotation axis as an electric signal. However, the force sensor 10 is not limited to this, and may be configured to output only one of the force and the moment as an electric signal, or may be configured to output at least one axial component of the force or the moment as an electric signal.

[0037] 2 and 3, the force sensor 10 includes a force receiving body 20, a fixed body 25, strain generating bodies 30A to 30D, a detection element 70, a detection circuit 75, and an exterior body 80. Each of the components will be described in more detail below.

[0038] Force receiving body 20 is an example of a first sensor body. Force receiving body 20 is acted upon by a force or moment to be detected. This action causes force receiving body 20 to move relative to fixed body 25. In the example of FIG. 1 described above, force receiving body 20 is fixed to tool 3 with a bolt or the like, and receives a force or moment from tool 3. Strain generating bodies 30A to 30D are connected to force receiving body 20.

[0039] 3, in this embodiment, the planar shape of force receiving body 20 is circular. However, the planar shape of force receiving body 20 is not limited to a circle, and may be rectangular or any other shape. Force receiving body 20 may be formed in a flat plate shape.

[0040] As shown in FIG. 2, fixed body 25 is an example of a second sensor body. Fixed body 25 supports force receiving body 20. Fixed body 25 is disposed at a different position from force receiving body 20 in the Z-axis direction. More specifically, fixed body 25 is disposed on the negative side of force receiving body 20 in the Z-axis direction. Force receiving body 20 and fixed body 25 are disposed at different positions from each other in the Z-axis direction, and fixed body 25 is spaced apart from force receiving body 20. In the example of FIG. 1, fixed body 25 is fixed to the tip of robot arm 4 with a bolt or the like, and is supported by robot main body 2. Strain generating bodies 30A to 30D are connected to fixed body 25.

[0041] As shown in FIG. 3, in this embodiment, the planar shape of fixed body 25 is circular, similar to force receiving body 20. However, the planar shape of fixed body 25 is not limited to circular, and may be rectangular or any other shape. Fixed body 25 may be formed in a flat plate shape. At least one of the planar shapes of force receiving body 20 and fixed body 25 may be circular. In this case, one of the planar shapes of force receiving body 20 and fixed body 25 may be circular, and the other may be a shape other than circular.

[0042] 2 and 3, the flexure bodies 30A to 30D connect the force receiving body 20 and the fixed body 25. More specifically, the flexure bodies 30A to 30D are disposed between the force receiving body 20 and the fixed body 25, and the flexure bodies 30A to 30D are connected to the force receiving body 20 and the fixed body 25. The force receiving body 20 is supported by the fixed body 25 via these flexure bodies 30A to 30D.

[0043] In this embodiment, the force receiving body 20 and the fixed body 25 may be connected by four flexure bodies 30A to 30D. The four flexure bodies 30A to 30D may include a first flexure body 30A, a second flexure body 30B, a third flexure body 30C, and a fourth flexure body 30D. As shown in FIG. 3, when viewed in the Z-axis direction, the first flexure body 30A may be disposed on the Y-axis direction positive side with respect to the center O of the force receiving body 20. Similarly, when viewed in the Z-axis direction, the second flexure body 30B may be disposed on the X-axis direction negative side with respect to the center O of the force receiving body 20. The third flexure body 30C may be disposed on the Y-axis direction negative side with respect to the center O of the force receiving body 20. The fourth flexure body 30D may be disposed on the X-axis direction positive side with respect to the center O of the force receiving body 20. In this case, the center O of the force receiving body 20 is disposed between the first flexure body 30A and the third flexure body 30C, and the center O of the force receiving body 20 is disposed between the second flexure body 30B and the fourth flexure body 30D. The number of flexure bodies connecting the force receiving body 20 and the fixed body 25 is not limited to four, and may be two, three, or five or more, and is arbitrary. The force receiving body 20 and the fixed body 25 may be connected by only one flexure body. In this case, if the detection element 70 is configured with two capacitance elements as shown in FIG. 4, it is possible to detect two-axis components of the force as described later. The detection element 70 may be configured with only one capacitance element to detect one-axis components of the force.

[0044] As shown in FIG. 3, the tilting structures 31 (described later) of the four flexure bodies 30A to 30D according to this embodiment are arranged in an annular shape. That is, as described above, the force receiving body 20 and the fixed body 25 are formed in a circular shape when viewed in the Z-axis direction, and the tilting structures 31 of the four flexure bodies 30A to 30D are arranged to form a rectangular annular shape. The tilting structures 31 of the respective flexure bodies 30A to 30D are formed linearly along the second direction when viewed in the Z-axis direction. That is, the second direction of the first flexure body 30A and the second direction of the third flexure body 30C correspond to the X-axis direction. The tilting structures 31 of the first flexure body 30A and the tilting structures 31 of the third flexure body 30C are formed linearly along the X-axis direction. The second direction of the second flexure body 30B and the second direction of the fourth flexure body 30D correspond to the Y-axis direction. The tilting structure 31 of the second flexure body 30B and the tilting structure 31 of the fourth flexure body 30D are formed linearly along the Y-axis direction. The second direction of each of the flexure bodies 30A-30D is not limited to the example shown in FIG. 3 and is arbitrary. The second direction of each of the flexure bodies 30A-30D does not have to be along either the X-axis direction or the Y-axis direction. For example, the arrangement of the four flexure bodies 30A-30D is not limited to annular arrangement and each may be irregularly arranged at any position.

[0045] Next, the flexure bodies 30A to 30D according to this embodiment will be described more specifically.

[0046] The flexure bodies 30A-30D according to this embodiment are configured to elastically deform and distort due to the action of a force or moment received by the force receiving body 20, and thus displace. Here, of the four flexure bodies 30A-30D described above, the first flexure body 30A, whose second direction is the X-axis direction, will be described as an example. The second flexure body 30B, the third flexure body 30C, and the fourth flexure body 30D have the same configuration, and therefore detailed description thereof will be omitted here.

[0047] As shown in FIGS. 2 and 4, the first flexure body 30A may include a tilting structure 31, a first connecting portion 32, a second connecting portion 33, and an opening .

[0048] The tilting structure 31 is disposed between the force receiving body 20 and the fixed body 25. The tilting structure 31 is disposed on an XZ plane including the Z-axis direction and the X-axis direction perpendicular to the Z-axis direction. When viewed in the Y-axis direction, the tilting structure 31 may be formed in a generally rectangular shape along the X-axis direction and the Y-axis direction. The tilting structure 31 may be formed symmetrically with respect to a central axis CL in the X-axis direction and a central axis CL extending in the Z-axis direction. Similarly, the opening 34 may be formed in a rectangular shape along the X-axis direction and the Y-axis direction. Details of the tilting structure 31 will be described later.

[0049] The first connection portion 32 connects the force receiving body 20 and the tilting structure 31. The first connection portion 32 extends in the Z-axis direction from the force receiving body 20 to the tilting structure 31. The first connection portion 32 may extend to the opening 34 described above. The first connection portion 32 may include a first connection opposing surface 32a that faces a second connection opposing surface 33a (described later) of the second connection portion 33. The second connection opposing surface 33a defines the opening 34.

[0050] First connecting portion 32 according to the present embodiment has a relatively large dimension in the X-axis direction. Furthermore, first connecting portion 32 has a relatively large planar area. More specifically, as shown in Figures 4 and 5, first connecting portion 32 includes first abutment surface 32b that abuts against force receiving body 20, and the area of ​​first abutment surface 32b is relatively large. First abutment surface 32b may be formed with a plurality of bolt holes 32c into which bolts (not shown) for attaching first connecting portion 32 to force receiving body 20 are inserted.

[0051] The second connection part 33 connects the fixed body 25 and the tilting structure 31. The second connection part 33 extends in the Z-axis direction from the fixed body 25 to the tilting structure 31. The second connection part 33 may extend to the above-mentioned opening 34. The second connection part 33 may include a second connection facing surface 33a facing the above-mentioned first connection facing surface 32a of the first connection part 32.

[0052] The second connecting portion 33 according to the present embodiment has a relatively large X-axis dimension. The second connecting portion 33 has a relatively large planar area. More specifically, as shown in FIG. 4, the second connecting portion 33 includes a second contact surface 33b that contacts the fixed body 25, and the area of ​​the second contact surface 33b is relatively large. The second contact surface 33b may have a plurality of bolt holes (not shown) formed therein, into which bolts (not shown) for attaching the second connecting portion 33 to the fixed body 25 are inserted, similar to the bolt holes 32c described above. The Z-axis dimension (see Lz2 in FIG. 14) of the second connecting portion 33 may be equal to or different from the Z-axis dimension (see Lz1 in FIG. 14) of the first connecting portion 32.

[0053] The first connection part 32 and the second connection part 33 are disposed at positions overlapping each other when viewed in the Z-axis direction. That is, the first connection part 32 and the second connection part 33 are disposed at the same position in the X-axis direction. The first connection part 32 and the second connection part 33 may be disposed at the center of the tilting structure 31 in the X-axis direction.

[0054] The tilting structure 31 includes a pair of first tilting portions 35L, 35R, a pair of first deformation portions 36, a pair of second tilting portions 37L, 37R, a pair of second deformation portions 38, and a pair of third deformation portions 39.

[0055] Each of the first tilting portions 35L, 35R is connected to the first connection portion 32. The first tilting portions 35L, 35R are disposed on both sides of the first connection portion 32 in the X-axis direction. The first tilting portion 35L is disposed on the negative side of the X-axis direction with respect to the first connection portion 32. The first tilting portion 35R is disposed on the positive side of the X-axis direction with respect to the first connection portion 32. The first tilting portions 35L, 35R are disposed closer to the force receiving body 20 than the second tilting portions 37L, 37R, and are disposed at positions closer to the force receiving body 20 than the second tilting portions 37L, 37R. The first tilting portions 35L, 35R are disposed closer to the force receiving body 20 than the opening 34 described above.

[0056] The first tilting portions 35L, 35R are configured to tilt with respect to the X-axis when the first strain body 30A elastically deforms. Each of the first tilting portions 35L, 35R includes a first tilting facing surface 35a that faces the force receiving body 20. A first displacement body 50, which will be described later, may be attached to the first tilting facing surface 35a of one of the first tilting portions 35L.

[0057] Each of the first deformation portions 36 connects the corresponding first tilting portions 35L, 35R to the first connection portion 32. The first deformation portions 36 are configured to be elastically deformable when the first strain body 30A elastically deforms. The first deformation portions 36 are disposed closer to the force receiving body 20 than the opening 34 described above.

[0058] The Z-axis dimension t1 of the first deformation portion 36 may be smaller than the Z-axis dimension t2 of the first tilting portions 35L and 35R. This makes it easier for the first deformation portion 36 to elastically deform. In FIG. 4, the Z-axis dimension of the first tilting portion 35R is indicated as t2, but the Z-axis dimension of the first tilting portion 35L may be equal to the Z-axis dimension t2 of the first tilting portion 35R. The lower surface of the first deformation portion 36 may be flush with the first connection facing surface 32a of the first connection portion 32. The lower surface of the first deformation portion 36 defines the opening 34 described above.

[0059] The first deformation portion 36 includes a first opposing surface 36a that faces the force receiving body 20. The first opposing surface 36a according to the present embodiment may be formed in a flat shape. The first opposing surface 36a is disposed closer to the fixed body 25 than the above-mentioned first tilting opposing surface 35a. As a result, a concave first cutout 40 is formed between the first connection portion 32 and each of the first tilting portions 35L and 35R so as to open toward the force receiving body 20. The first cutout 40 reduces the Z-axis dimension t1 of the first deformation portion 36. As shown in FIG. 4, the first cutout 40 may be formed in a rectangular shape when viewed in the Y-axis direction.

[0060] Each of the second tilting portions 37L, 37R is connected to the second connection portion 33. The second tilting portions 37L, 37R are disposed on both sides of the second connection portion 33 in the X-axis direction. The second tilting portion 37L is disposed on the negative side of the X-axis direction with respect to the second connection portion 33. The second tilting portion 37R is disposed on the positive side of the X-axis direction with respect to the second connection portion 33. The second tilting portions 37L, 37R are disposed closer to the fixed body 25 than the first tilting portions 35L, 35R, and are disposed at positions closer to the fixed body 25 than the first tilting portions 35L, 35R. The second tilting portions 37L, 37R are disposed closer to the fixed body 25 than the opening 34 described above.

[0061] The second tilting portions 37L and 37R are configured to tilt with respect to the X-axis when the first strain body 30A elastically deforms. Each of the second tilting portions 37L and 37R includes a second tilting facing surface 37a that faces the fixed body 25. A second displacement body 60, which will be described later, is attached to the second tilting facing surface 37a of one of the second tilting portions 37R.

[0062] Each of the second deformation portions 38 connects the corresponding second tilting portions 37L, 37R to the second connection portion 33. The second deformation portions 38 are configured to be elastically deformable when the first strain body 30A elastically deforms. The second deformation portions 38 are disposed closer to the fixed body 25 than the opening 34 described above.

[0063] The Z-axis dimension t3 of the second deformation portion 38 may be smaller than the Z-axis dimension t4 of the second tilting portions 37L and 37R. This makes it easier for the second deformation portion 38 to elastically deform. In FIG. 4, the Z-axis dimension of the second tilting portion 37L is indicated as t4, but the Z-axis dimension of the second tilting portion 37R may be equal to the Z-axis dimension t4 of the second tilting portion 37L. The upper surface of the second deformation portion 38 may be flush with the second connection facing surface 33a of the second connection portion 33. The upper surface of the second deformation portion 38 defines the opening 34 described above.

[0064] The second deformation portion 38 includes a second opposing surface 38a that faces the fixed body 25. The second opposing surface 38a according to the present embodiment may be formed in a flat shape. The second opposing surface 38a is disposed closer to the force receiving body 20 than the above-mentioned second tilting opposing surface 37a. As a result, a concave second cutout 41 is formed between the second connection portion 33 and each of the second tilting portions 37L and 37R so as to open toward the fixed body 25, and the Z-axis direction dimension t3 of the second deformation portion 38 is reduced by the second cutout 41. As shown in FIG. 4, the second cutout 41 may be formed in a rectangular shape when viewed in the Y-axis direction.

[0065] Each of the third deformation parts 39 connects the corresponding first tilting parts 35L, 35R and the corresponding second tilting parts 37L, 37R. The third deformation parts 39 are configured to be elastically deformable when the first strain body 30A elastically deforms. The third deformation parts 39 are respectively arranged on the X-axis positive side and the X-axis negative side with respect to the opening 34. The third deformation part 39 arranged on the X-axis positive side connects the first tilting part 35R and the second tilting part 37R. The third deformation part 39 arranged on the X-axis negative side connects the first tilting part 35L and the second tilting part 37L arranged on the X-axis negative side.

[0066] The X-axis dimension t5 of the third deformation portion 39 may be smaller than the X-axis dimension t6 of the first tilting portions 35L and 35R, and may be smaller than the X-axis dimension t7 of the second tilting portions 37L and 37R. This makes it easier for the third deformation portion 39 to elastically deform. In FIG. 4, the X-axis dimension of the first tilting portion 35R is indicated by t6, but the X-axis dimension of the first tilting portion 35L may be equal to the X-axis dimension t6 of the first tilting portion 35R. The X-axis dimension of the second tilting portion 37L is indicated by t7, but the X-axis dimension of the second tilting portion 37R may be equal to the X-axis dimension t7 of the second tilting portion 37L. The surface on the negative side in the X axis direction (left side in FIG. 4) of the third deformation portion 39 arranged on the negative side in the X axis direction may be flush with the negative side surface in the X axis direction of the corresponding first tilting portion 35L, or may be flush with the negative side surface in the X axis direction of the corresponding second tilting portion 37L. The surface on the positive side in the X axis direction (right side in FIG. 4) of the third deformation portion 39 arranged on the positive side in the X axis direction may be flush with the positive side surface in the X axis direction of the corresponding first tilting portion 35R, or may be flush with the positive side surface in the X axis direction of the corresponding second tilting portion 37R.

[0067] Each of the third deformation parts 39 includes a flat third opposing surface 39a that faces the other third deformation parts 39. The third opposing surface 39a according to this embodiment is disposed in a YZ plane including the Y-axis direction and the Z-axis direction. The third opposing surface 39a defines the above-mentioned opening 34. In this embodiment, the opening 34 extends to a position between the first tilting part 35L and the second tilting part 37L, and also extends to a position between the first tilting part 35R and the second tilting part 37R. In other words, the opening 34 overlaps a part of the first tilting part 35L and the second tilting part 37L, and also overlaps a part of the first tilting part 35R and the second tilting part 37R, when viewed in the Z-axis direction.

[0068] The first strain body 30A includes a first displacement body 50 and a second displacement body 60. The first displacement body 50 is connected to a first tilting portion 35L disposed on the negative side in the X-axis direction with respect to the first connection portion 32. The second displacement body 60 is connected to a second tilting portion 37R disposed on the positive side in the X-axis direction with respect to the second connection portion 33.

[0069] 4, the first displacement body 50 may include a first connecting portion 51, a first extending portion 52, a first arm portion 53, and a first displacement portion 54. The first connecting portion 51, the first extending portion 52, the first arm portion 53, and the first displacement portion 54 may be formed integrally and continuously.

[0070] The first connecting part 51 may be attached to the above-mentioned first tilting facing surface 35a of the first tilting part 35L. The first connecting part 51 may include a first connecting abutment surface 51a that faces and abuts against the first tilting facing surface 35a. The first connecting part 51 may be attached to the first tilting facing surface 35a using a bolt or the like (not shown). However, the first connecting part 51 may be attached to the surface on the positive side in the Y-axis direction or the surface on the negative side in the Y-axis direction of the first tilting part 35L. As shown in FIG. 5 and FIG. 6, the first connecting part 51 may extend from the tilting structure 31 to the negative side in the Y-axis direction.

[0071] 4 and 6, the first extension 52 may extend from the tip of the first connecting part 51 in a direction toward the fixed body 25. More specifically, the first extension 52 may extend downward from the tip of the first connecting part 51 on the negative side in the Z axis direction. The tip of the first connecting part 51 is the end part on the negative side in the Y axis direction of the first connecting part 51. The first extension 52 is disposed on the negative side in the Y axis direction with respect to the tilting structure 31.

[0072] 4 and 5, the first arm 53 extends in the X-axis direction from the corresponding first tilting portion 35L to the other first tilting portion 35R. More specifically, the first arm 53 is attached to the first tilting opposing surface 35a via a first connecting portion 51 and a first extending portion 52. The first arm 53 extends from the lower end of the first extending portion 52 to the X-axis direction positive side. The first arm 53 is disposed on the Y-axis direction negative side with respect to the tilting structure 31.

[0073] The first displacement portion 54 is connected to the first tilting portion 35L via the first connecting portion 51, the first extending portion 52, and the first arm portion 53. The first displacement portion 54 according to the present embodiment is disposed on the side of the other first tilting portion 35R with respect to the corresponding first tilting portion 35L, and is disposed on the X-axis direction positive side with respect to the first tilting portion 35L. The first displacement portion 54 may be disposed at the tip of the first arm portion 53. The tip of the first arm portion 53 is the end portion of the first arm portion 53 on the X-axis direction positive side. However, the first displacement portion 54 of the first flexure body 30A according to the present embodiment is disposed on the X-axis direction negative side with respect to a second displacement portion 64 of the first flexure body 30A, which will be described later. As shown in FIG. 4, the first displacement portion 54 may be disposed on the X-axis direction negative side with respect to the central axis CL of the tilting structure 31. The first displacement portion 54 is provided with a second displacement electrode substrate Ed2, which will be described later.

[0074] 4, the second displacement body 60 may include a second connecting portion 61, a second extending portion 62, a second arm portion 63, and a second displacement portion 64. The second connecting portion 61, the second extending portion 62, the second arm portion 63, and the second displacement portion 64 may be formed integrally and continuously.

[0075] The second connecting part 61 may be attached to the above-mentioned second tilting facing surface 37a of the second tilting part 37R. The second connecting part 61 may include a second connecting abutment surface 61a that faces and abuts against the second tilting facing surface 37a. The second connecting part 61 may be attached to the second tilting facing surface 37a using a bolt or the like (not shown). However, the second connecting part 61 may be attached to the surface on the positive side of the Y axis direction or the surface on the negative side of the Y axis direction of the second tilting part 37R. As shown in FIG. 5 and FIG. 6, the second connecting part 61 may extend from the tilting structure 31 to the negative side of the Y axis direction.

[0076] 4, the second extension portion 62 may extend in a direction from the tip of the second connecting portion 61 toward the force receiving body 20. More specifically, the second extension portion 62 may extend upward from the tip of the second connecting portion 61 on the positive side in the Z axis direction. The tip of the second connecting portion 61 is the end portion of the second connecting portion 61 on the negative side in the Y axis direction. The second extension portion 62 is disposed on the negative side in the Y axis direction with respect to the tilting structure 31.

[0077] 4 and 5, the second arm 63 extends in the X-axis direction from the corresponding second tilting portion 37R to the other second tilting portion 37L. More specifically, the second arm 63 is attached to the second tilting opposing surface 37a via the second connecting portion 61 and the second extending portion 62. The second arm 63 extends from the upper end of the second extending portion 62 to the X-axis direction negative side. The second arm 63 is disposed on the Y-axis direction negative side with respect to the tilting structure 31.

[0078] The second displacement portion 64 is connected to the second tilting portion 37R via the second connecting portion 61, the second extending portion 62, and the second arm portion 63. The second displacement portion 64 according to the present embodiment is disposed on the side of the other second tilting portion 37L with respect to the corresponding second tilting portion 37R, and is disposed on the negative side in the X-axis direction with respect to the second tilting portion 37R. The second displacement portion 64 may be disposed at the tip of the second arm portion 63. The tip of the second arm portion 63 is the end portion of the second arm portion 63 on the negative side in the X-axis direction. However, the second displacement portion 64 of the first flexure body 30A according to the present embodiment is disposed on the positive side in the X-axis direction with respect to the first displacement portion 54 of the first flexure body 30A. As shown in FIG. 4, the second displacement portion 64 may be disposed on the positive side in the X-axis direction with respect to the central axis CL of the tilting structure 31. The second displacement portion 64 is provided with a first displacement electrode substrate Ed1 to be described later.

[0079] As shown in FIG. 3, the first displacement portion 54 and the second displacement portion 64 of the first flexure body 30A are disposed on the center side of the force receiving body 20 with respect to the tilting structure 31 of the first flexure body 30A. More specifically, the first displacement portion 54 and the second displacement portion 64 are disposed on the Y-axis negative side with respect to the tilting structure 31, and disposed on one side of the tilting structure 31. As described above, the first displacement portion 54 of the first flexure body 30A is disposed on the X-axis negative side with respect to the central axis CL (see FIG. 4) of the tilting structure 31 of the first flexure body 30A, and the second displacement portion 64 of the first flexure body 30A is disposed on the X-axis positive side with respect to the central axis CL. The first displacement portion 54 and the second displacement portion 64 of the first flexure body 30A are configured to be displaced to opposite sides to each other in the Z-axis direction when the force receiving body 20 receives a force Fz in the Z-axis direction. Details of the displacement state of the first displacement portion 54 and the second displacement portion 64 will be described later.

[0080] As shown in FIG. 3, the first displacement portion 54 and the second displacement portion 64 of the second flexure body 30B are disposed on the center side of the force receiving body 20 with respect to the tilting structure 31 of the second flexure body 30B. More specifically, the first displacement portion 54 and the second displacement portion 64 are disposed on the X-axis positive side with respect to the tilting structure 31, and disposed on one side of the tilting structure 31. The first displacement portion 54 of the second flexure body 30B is disposed on the Y-axis positive side with respect to the central axis CL (see FIG. 4) of the tilting structure 31 of the second flexure body 30B, and the second displacement portion 64 of the second flexure body 30B is disposed on the Y-axis negative side with respect to the central axis CL. The first displacement portion 54 and the second displacement portion 64 of the second flexure body 30B are configured to be displaced to opposite sides to each other in the Z-axis direction when the force receiving body 20 receives a force Fz in the Z-axis direction.

[0081] As shown in FIG. 3, the first displacement portion 54 and the second displacement portion 64 of the third flexure body 30C are disposed on the center side of the force receiving body 20 with respect to the tilting structure 31 of the third flexure body 30C. More specifically, the first displacement portion 54 and the second displacement portion 64 are disposed on the Y-axis positive side with respect to the tilting structure 31, and disposed on one side of the tilting structure 31. The first displacement portion 54 of the third flexure body 30C is disposed on the X-axis positive side with respect to the central axis CL (see FIG. 4) of the tilting structure 31 of the third flexure body 30C, and the second displacement portion 64 of the third flexure body 30C is disposed on the X-axis negative side with respect to the central axis CL. The first displacement portion 54 and the second displacement portion 64 of the third flexure body 30C are configured to be displaced to opposite sides to each other in the Z-axis direction when the force receiving body 20 receives a force Fz in the Z-axis direction.

[0082] As shown in FIG. 3, the first displacement portion 54 and the second displacement portion 64 of the fourth flexure body 30D are disposed on the center side of the force receiving body 20 with respect to the tilting structure 31 of the fourth flexure body 30D. More specifically, the first displacement portion 54 and the second displacement portion 64 are disposed on the negative side in the X-axis direction with respect to the tilting structure 31, and disposed on one side of the tilting structure 31. The first displacement portion 54 of the fourth flexure body 30D is disposed on the negative side in the Y-axis direction with respect to the central axis CL (see FIG. 4) of the tilting structure 31 of the fourth flexure body 30D, and the second displacement portion 64 of the fourth flexure body 30D is disposed on the positive side in the Y-axis direction with respect to the central axis CL. The first displacement portion 54 and the second displacement portion 64 of the fourth flexure body 30D are configured to be displaced to opposite sides to each other in the Z-axis direction when the force receiving body 20 receives a force Fz in the Z-axis direction.

[0083] The detection element 70 is configured to detect a displacement caused by the elastic deformation of the above-mentioned first strain body 30 A. The detection element 70 according to the present embodiment is configured as an element for detecting electrostatic capacitance.

[0084] As shown in FIG. 4, the detection element 70 includes a first capacitance element C1 and a second capacitance element C2. The first capacitance element C1 detects a change in capacitance value due to the displacement of one of the first displacement portion 54 and the second displacement portion 64 in the Z-axis direction. The second capacitance element C2 detects a change in capacitance value due to the displacement of the other of the first displacement portion 54 and the second displacement portion 64 in the Z-axis direction. The first capacitance element C1 and the second capacitance element C2 are capacitance elements for the first strain body 30A shown in FIG. 4. The displacement portion that is the object of detection of the displacement of the first capacitance element C1 and the displacement portion that is the object of detection of the displacement of the second capacitance element C2 may be different displacement portions of the first displacement portion 54 and the second displacement portion 64. In this embodiment, the first capacitance element C1 detects a change in capacitance value due to the displacement of the second displacement portion 64 of the first strain body 30A in the Z-axis direction, and the second capacitance element C2 detects a change in capacitance value due to the displacement of the first displacement portion 54 of the first strain body 30A in the Z-axis direction. However, the first capacitance element C1 may detect a change in capacitance value due to the displacement of the first displacement portion 54 in the Z-axis direction, and the second capacitance element C2 may detect a change in capacitance value due to the displacement of the second displacement portion 64 in the Z-axis direction.

[0085] 4, the first capacitance element C1 includes a first displacement electrode substrate Ed1 provided on one of the first displacement portion 54 and the second displacement portion 64, and a first fixed electrode substrate Ef1 facing the first displacement electrode substrate Ed1. The second capacitance element C2 includes a second displacement electrode substrate Ed2 provided on the other of the first displacement portion 54 and the second displacement portion 64, and a second fixed electrode substrate Ef2 facing the second displacement electrode substrate Ed2. In the present embodiment, the first fixed electrode substrate Ef1 and the second fixed electrode substrate Ef2 are supported by the fixed body 25.

[0086] The first fixed electrode substrate Ef1 is disposed on the X-axis direction positive side with respect to the central axis CL of the tilting structure 31 of the first flexure body 30A. The second fixed electrode substrate Ef2 is disposed on the X-axis direction negative side with respect to the central axis CL. The first fixed electrode substrate Ef1 may be supported by the fixed body 25 via the second pedestal 27, and the second fixed electrode substrate Ef2 may be supported by the fixed body 25 via the first pedestal 26. Each pedestal 26, 27 may be fixed to the surface of the fixed body 25 on the side of the force receiving body 20. In this case, the fixed electrode substrates Ef1, Ef2 may be bonded to the upper surfaces of the pedestals 26, 27 with an adhesive or may be fixed with bolts or the like. The fixed electrode substrates Ef1, Ef2 include fixed electrodes Ef facing the corresponding displacement electrode substrates Ed1, Ed2, and insulators IBf (see FIG. 6) interposed between the fixed electrodes Ef and the pedestals 26, 27. The fixed electrode Ef is fixed to the pedestals 26, 27 via an insulator IBf. The first pedestal 26 and the second pedestal 27 may be formed separately, or may be formed integrally and continuously. The first pedestal 26 and the second pedestal 27 may be fixed to the fixed body 25 with a bolt or the like, or may be formed integrally and continuously with the fixed body 25.

[0087] The first displacement electrode substrate Ed1 is disposed on the X-axis direction positive side with respect to the central axis CL of the tilting structure 31 of the first flexure body 30A. The second displacement electrode substrate Ed2 is disposed on the X-axis direction negative side with respect to the central axis CL. In this embodiment, the first displacement electrode substrate Ed1 of the first flexure body 30A is provided on the second displacement portion 64, and the second displacement electrode substrate Ed2 is provided on the first displacement portion 54. In this embodiment, the displacement electrode substrates Ed1, Ed2 are provided on the surface of the corresponding displacement portion 64, 54 on the fixed body 25 side. The displacement electrode substrates Ed1, Ed2 may be bonded to the surface of the corresponding displacement portion 64, 54 on the fixed body 25 side with an adhesive, or may be fixed with a bolt or the like. The displacement electrode substrates Ed1, Ed2 include a displacement electrode Ed facing the corresponding fixed electrode substrates Ef1, Ef2, and an insulator IBd (see FIG. 6) interposed between the displacement electrode Ed and the displacement portion 64, 54. The displacement electrode Ed is fixed to the displacement portions 64, 54 via an insulator IBd.

[0088] The first fixed electrode substrate Ef1 faces the first displacement electrode substrate Ed1 and is disposed below the first displacement electrode substrate Ed1. The first fixed electrode substrate Ef1, together with the first displacement electrode substrate Ed1, is disposed on the X-axis direction positive side with respect to the central axis CL of the tilting structure 31 of the first flexure body 30A. The second fixed electrode substrate Ef2 faces the second displacement electrode substrate Ed2 and is disposed below the second displacement electrode substrate Ed2. The second fixed electrode substrate Ef2, together with the second displacement electrode substrate Ed2, is disposed on the X-axis direction negative side with respect to the central axis CL. In a state where the force receiving body 20 is not subjected to the action of a force or moment, the Z-axis direction position of the first displacement electrode substrate Ed1 and the Z-axis direction position of the second displacement electrode substrate Ed2 may be equal. In this case, the inter-electrode distance between the first displacement electrode substrate Ed1 and the first fixed electrode substrate Ef1 and the inter-electrode distance between the second displacement electrode substrate Ed2 and the second fixed electrode substrate Ef2 may be equal.

[0089] The first capacitance element C1 and the second capacitance element C2 are disposed at the same position in the Y-axis direction. That is, as shown in Fig. 3, Fig. 5, and Fig. 6, the first displacement electrode substrate Ed1 and the second displacement electrode substrate Ed2 are disposed at the same position in the Y-axis direction, and the first fixed electrode substrate Ef1 and the second fixed electrode substrate Ef2 are also disposed at the same position in the Y-axis direction. As shown in Fig. 3, Fig. 5, and Fig. 6, the first capacitance element C1 and the second capacitance element C2 are disposed on the negative side in the Y-axis direction with respect to the tilting structure 31.

[0090] In this embodiment, the planar shape of the fixed electrode substrates Ef1 and Ef2 is rectangular. The planar shape of the displacement electrode substrates Ed1 and Ed2 is also rectangular. However, the planar shapes of the fixed electrode substrates Ef1 and Ef2 and the displacement electrode substrates Ed1 and Ed2 are not limited to rectangular, and may be other shapes such as circular, polygonal, or elliptical.

[0091] When viewed in the Z-axis direction, the first fixed electrode substrate Ef1 may be formed larger than the first displaceable electrode substrate Ed1. For example, the planar shape of the first fixed electrode substrate Ef1 may be larger than the planar shape of the first displaceable electrode substrate Ed1. And, even if the first displaceable electrode substrate Ed1 is displaced in the X-axis direction, the Y-axis direction, or the Z-axis direction, the first displaceable electrode substrate Ed1 may overlap the first fixed electrode substrate Ef1 as a whole when viewed in the Z-axis direction. In other words, the size of the displaceable electrode Ed and the size of the fixed electrode Ef may be set so that the displaceable electrode Ed and the fixed electrode Ef constituting the first capacitance element C1 overlap even if the first displaceable electrode substrate Ed1 is displaced in the X-axis direction, the Y-axis direction, or the Z-axis direction. In this way, even if the first displaceable electrode substrate Ed1 is displaced, it is possible to prevent the opposing area of ​​the displaceable electrode Ed and the fixed electrode Ef from changing, and it is possible to prevent the change in the opposing area from affecting the change in the capacitance value. Therefore, it is possible to change the capacitance value according to the change in the distance between the displaceable electrode Ed and the fixed electrode Ef. Here, the facing area refers to the area where the displacement electrode Ed and the fixed electrode Ef overlap when viewed in the Z-axis direction. When the tilting structure 31 tilts, the displacement electrode Ed, which is smaller than the fixed electrode Ef, may tilt and the facing area may change, but the tilt angle of the displacement electrode Ed in this case is small. As a result, the distance between the displacement electrode Ed and the fixed electrode Ef is dominant in the change in the capacitance value. For this reason, in this specification, the change in the facing area due to the tilt of the displacement electrode Ed is not taken into consideration, and the change in the capacitance value is considered to be caused by the change in the distance between the displacement electrode Ed and the fixed electrode Ef. Note that in FIG. 8 and other figures described later, the tilt of the tilting structure 31 is exaggerated in order to clarify the drawing. In addition, the planar shape of the first fixed electrode substrate Ef1 is not limited to being larger than the planar shape of the first displacement electrode substrate Ed1, and the planar shape of the first displacement electrode substrate Ed1 may be larger than the planar shape of the first fixed electrode substrate Ef1.

[0092] Similarly, when viewed in the Z-axis direction, the planar shape of the second fixed electrode substrate Ef2 may be larger than the planar shape of the second displaceable electrode substrate Ed2. Note that the planar shape of the second displaceable electrode substrate Ed2 may be larger than the planar shape of the second fixed electrode substrate Ef2.

[0093] The planar shape of the fixed electrodes Ef of the fixed electrode substrates Ef1 and Ef2 and the planar shape of the insulator IBf may be the same size. However, this is not limited to the above, and the planar shape of the fixed electrodes Ef may be smaller than the planar shape of the insulator IBf. The same is true for the planar shapes of the displacement electrodes Ed of the displacement electrode substrates Ed1 and Ed2 and the insulator IBd.

[0094] The insulator IBf may be made of an insulating material such as glass epoxy resin or ceramic. Alternatively, the fixed electrode substrates Ef1, Ef2 may be made of an FPC substrate (flexible printed circuit board). The FPC substrate is a printed substrate formed in a thin film shape and has flexibility. The FPC substrate has a thin metal film formed on the upper surface of a polyimide film, which constitutes electrodes and wiring. Parts of the FPC substrate corresponding to the fixed electrode substrates Ef1, Ef2 may be fixed to the pedestals 26, 27. The FPC substrate may include wiring that connects the fixed electrode Ef to the detection circuit 75.

[0095] Like the insulator IBf, the insulator IBd may be made of an insulating material such as glass epoxy resin or ceramic. Alternatively, the displacement electrode substrates Ed1 and Ed2 may be made of an FPC substrate (flexible printed circuit board). Parts of the FPC substrate corresponding to the displacement electrode substrates Ed1 and Ed2 may be fixed to the displacement sections 54 and 64. The FPC substrate may include wiring that connects the displacement electrodes Ed to the detection circuit 75.

[0096] The first fixed electrode substrate Ef1 and the second fixed electrode substrate Ef2 may be formed separately and spaced apart from each other, as shown in FIG. 4. However, the present invention is not limited to this. The first fixed electrode substrate Ef1 and the second fixed electrode substrate Ef2 may be integrated to form one common fixed electrode substrate. In this case, the insulator IBf of the first fixed electrode substrate Ef1 and the insulator IBf of the second fixed electrode substrate Ef2 may be integrated, and the fixed electrode Ef of the first fixed electrode substrate Ef1 and the fixed electrode Ef of the second fixed electrode substrate Ef2 may be integrated. The two pedestals 26, 27 may also be integrated to form one common pedestal. Even if the first fixed electrode substrate Ef1 and the second fixed electrode substrate Ef2 are formed separately, the two pedestals 26, 27 may be integrated.

[0097] The above-mentioned configuration of the first flexure body 30A and the corresponding detection element 70 can be similarly applied to the second flexure body 30B, the third flexure body 30C, and the fourth flexure body 30D.

[0098] That is, as shown in FIG. 3, the detection element 70 further includes a third capacitance element C3 and a fourth capacitance element C4. The third capacitance element C3 detects a change in the capacitance value due to the displacement in the Z-axis direction of one of the first displacement portion 54 and the second displacement portion 64 of the second flexure body 30B. The fourth capacitance element C4 detects a change in the capacitance value due to the displacement in the Z-axis direction of the other of the first displacement portion 54 and the second displacement portion 64. The third capacitance element C3 and the fourth capacitance element C4 are capacitance elements for the second flexure body 30B. In this embodiment, the third capacitance element C3 detects a change in the capacitance value due to the displacement in the Z-axis direction of the first displacement portion 54 of the second flexure body 30B, and the fourth capacitance element C4 detects a change in the capacitance value due to the displacement in the Z-axis direction of the second displacement portion 64 of the second flexure body 30B.

[0099] The third capacitive element C3 includes a third fixed electrode substrate Ef3 provided on the fixed body 25 and a third displaceable electrode substrate Ed3 facing the third fixed electrode substrate Ef3. The fourth capacitive element C4 includes a fourth fixed electrode substrate Ef4 provided on the fixed body 25 and a fourth displaceable electrode substrate Ed4 facing the fourth fixed electrode substrate Ef4.

[0100] The third displacement electrode substrate Ed3 and the third fixed electrode substrate Ef3 are disposed on the Y-axis direction positive side with respect to the central axis CL (see FIG. 4) of the tilting structure 31 of the second flexure body 30B. As described above, the first displacement portion 54 of the second flexure body 30B is disposed on the Y-axis direction positive side with respect to the central axis CL, and the third displacement electrode substrate Ed3 is supported by the first displacement portion 54. The third fixed electrode substrate Ef3 is supported by the fixed body 25 via the first pedestal 26 (see FIG. 4). The fourth displacement electrode substrate Ed4 and the fourth fixed electrode substrate Ef4 are disposed on the Y-axis direction negative side with respect to the central axis CL. As described above, the second displacement portion 64 of the second flexure body 30B is disposed on the Y-axis direction negative side with respect to the central axis CL, and the fourth displacement electrode substrate Ed4 is supported by the second displacement portion 64. The fourth fixed electrode substrate Ef4 is supported by the fixed body 25 via the second pedestal 27 (see FIG. 4).

[0101] The third capacitance element C3 and the fourth capacitance element C4 are disposed at the same position in the X-axis direction. As shown in Fig. 3, the third capacitance element C3 and the fourth capacitance element C4 are disposed on the X-axis direction positive side with respect to the tilting structure 31. The fixed electrode substrates Ef3 and Ef4 have the same configuration as the fixed electrode substrates Ef1 and Ef2 described above. The displacement electrode substrates Ed3 and Ed4 have the same configuration as the displacement electrode substrates Ed1 and Ed2 described above.

[0102] As shown in FIG. 3, the detection element 70 further includes a fifth capacitance element C5 and a sixth capacitance element C6. The fifth capacitance element C5 detects a change in capacitance value due to the displacement in the Z-axis direction of one of the first displacement portion 54 and the second displacement portion 64 of the third flexure body 30C. The sixth capacitance element C6 detects a change in capacitance value due to the displacement in the Z-axis direction of the other of the first displacement portion 54 and the second displacement portion 64. The fifth capacitance element C5 and the sixth capacitance element C6 are capacitance elements for the third flexure body 30C. In this embodiment, the fifth capacitance element C5 detects a change in capacitance value due to the displacement in the Z-axis direction of the second displacement portion 64 of the third flexure body 30C, and the sixth capacitance element C6 detects a change in capacitance value due to the displacement in the Z-axis direction of the first displacement portion 54 of the third flexure body 30C.

[0103] The fifth capacitive element C5 includes a fifth fixed electrode substrate Ef5 provided on the fixed body 25 and a fifth displaceable electrode substrate Ed5 facing the fifth fixed electrode substrate Ef5. The sixth capacitive element C6 includes a sixth fixed electrode substrate Ef6 provided on the fixed body 25 and a sixth displaceable electrode substrate Ed6 facing the sixth fixed electrode substrate Ef6.

[0104] The fifth displacement electrode substrate Ed5 and the fifth fixed electrode substrate Ef5 are disposed on the X-axis direction negative side with respect to the central axis CL (see FIG. 4) of the tilting structure 31 of the third flexure body 30C. As described above, the second displacement portion 64 of the third flexure body 30C is disposed on the X-axis direction negative side with respect to the central axis CL, and the fifth displacement electrode substrate Ed5 is supported by the second displacement portion 64. The fifth fixed electrode substrate Ef5 is supported by the fixed body 25 via the second pedestal 27 (see FIG. 4). The sixth displacement electrode substrate Ed6 and the sixth fixed electrode substrate Ef6 are disposed on the X-axis direction positive side with respect to the central axis CL. As described above, the first displacement portion 54 of the third flexure body 30C is disposed on the X-axis direction positive side with respect to the central axis CL, and the sixth displacement electrode substrate Ed6 is supported by the first displacement portion 54. The sixth fixed electrode substrate Ef6 is supported by the fixed body 25 via the first pedestal 26 (see FIG. 4).

[0105] The fifth capacitance element C5 and the sixth capacitance element C6 are disposed at the same position in the Y-axis direction. As shown in Fig. 3, the fifth capacitance element C5 and the sixth capacitance element C6 are disposed on the Y-axis direction positive side with respect to the tilting structure 31. The fixed electrode substrates Ef5 and Ef6 have the same configuration as the fixed electrode substrates Ef1 and Ef2 described above. The displacement electrode substrates Ed5 and Ed6 have the same configuration as the displacement electrode substrates Ed1 and Ed2 described above.

[0106] As shown in FIG. 3, the detection element 70 includes a seventh capacitance element C7 and an eighth capacitance element C8. The seventh capacitance element C7 detects a change in capacitance value due to the displacement in the Z-axis direction of one of the first displacement portion 54 and the second displacement portion 64 of the fourth flexure body 30D. The eighth capacitance element C8 detects a change in capacitance value due to the displacement in the Z-axis direction of the other of the first displacement portion 54 and the second displacement portion 64. The seventh capacitance element C7 and the eighth capacitance element C8 are capacitance elements for the fourth flexure body 30D. In this embodiment, the seventh capacitance element C7 detects a change in capacitance value due to the displacement in the Z-axis direction of the first displacement portion 54 of the fourth flexure body 30D, and the eighth capacitance element C8 detects a change in capacitance value due to the displacement in the Z-axis direction of the second displacement portion 64 of the fourth flexure body 30D.

[0107] The seventh capacitive element C7 includes a seventh fixed electrode substrate Ef7 provided on the fixed body 25 and a seventh displacement electrode substrate Ed7 facing the seventh fixed electrode substrate Ef7. The eighth capacitive element C8 includes an eighth fixed electrode substrate Ef8 provided on the fixed body 25 and an eighth displacement electrode substrate Ed8 facing the eighth fixed electrode substrate Ef8.

[0108] The seventh displacement electrode substrate Ed7 and the seventh fixed electrode substrate Ef7 are disposed on the Y-axis direction negative side with respect to the central axis CL (see FIG. 4) of the tilting structure 31 of the fourth flexure body 30D. As described above, the first displacement portion 54 of the fourth flexure body 30D is disposed on the Y-axis direction negative side with respect to the central axis CL, and the seventh displacement electrode substrate Ed7 is supported by the first displacement portion 54. The seventh fixed electrode substrate Ef7 is supported by the fixed body 25 via the first pedestal 26 (see FIG. 4). The eighth displacement electrode substrate Ed8 and the eighth fixed electrode substrate Ef8 are disposed on the Y-axis direction positive side with respect to the central axis CL. As described above, the second displacement portion 64 of the fourth flexure body 30D is disposed on the Y-axis direction positive side with respect to the central axis CL, and the eighth displacement electrode substrate Ed8 is supported by the second displacement portion 64. The eighth fixed electrode substrate Ef8 is supported by the fixed body 25 via the second pedestal 27 (see FIG. 4).

[0109] The seventh capacitance element C7 and the eighth capacitance element C8 are disposed at the same position in the X-axis direction. As shown in Fig. 3, the seventh capacitance element C7 and the eighth capacitance element C8 are disposed on the negative side in the X-axis direction with respect to the tilting structure 31. The fixed electrode substrates Ef7 and Ef8 have the same configuration as the fixed electrode substrates Ef1 and Ef2 described above. The displacement electrode substrates Ed7 and Ed8 have the same configuration as the displacement electrode substrates Ed1 and Ed2 described above.

[0110] As shown in Fig. 2, the detection circuit 75 outputs an electric signal indicating the force or moment acting on the strain bodies 30A-30D based on the detection result of the detection element 70. The detection circuit 75 may have a calculation function constituted by, for example, a microprocessor. The detection circuit 75 may also have an A / D conversion function for converting an analog signal received from the detection element 70 described above into a digital signal, and a signal amplification function. The detection circuit 75 may include a terminal for outputting an electric signal, and the electric signal is transmitted from this terminal to the controller 5 described above via an electric cable (not shown).

[0111] As shown in Figs. 2 and 3, the exterior body 80 is configured to cover the four flexure bodies 30A to 30D from the outside when viewed in the Z-axis direction. The exterior body 80 is a cylindrical housing that constitutes the force sensor 10. The flexure bodies 30A to 30D are housed in the exterior body 80. In this embodiment, the planar cross-sectional shape (shape in a cross section along the XY plane) of the exterior body 80 is a circular frame shape. A buffer member 81 may be interposed in the gap between the force receiving body 20 and the exterior body 80. The buffer member 81 may be formed of a flexible material that is elastically deformable, such as rubber or sponge.

[0112] Next, a method for detecting a force or moment acting on the force sensor 10 according to the present embodiment configured as described above will be described with reference to Figs. 8 to 10B. Fig. 8 is a front view showing a deformation state of the first flexure body 30A when the flexure body of Fig. 4 receives a force Fx in the positive X-axis direction, and Fig. 9 is a front view showing a deformation state of the first flexure body 30A when the flexure body of Fig. 4 receives a force Fy in the positive Y-axis direction. Fig. 10A is a front view showing a deformation state of the first flexure body 30A when the first flexure body 30A of Fig. 4 receives a force Fz in the positive Z-axis direction. Fig. 10B is a front view showing a deformation state of the first flexure body 30A when the first flexure body 30A of Fig. 4 receives a force Fz in the negative Z-axis direction.

[0113] When the force receiving body 20 is subjected to a force or moment, the force or moment is transmitted to the first flexure body 30A to the fourth flexure body 30D. More specifically, the force or moment is transmitted to the tilting structure 31, and the tilting structure 31 is elastically deformed. This causes displacement in the first displacement portion 54 and the second displacement portion 64 of the tilting structure 31. As a result, the distance between each of the fixed electrode substrates Ef1 to Ef8 of the detection element 70 and the corresponding displacement electrode substrates Ed1 to Ed8 changes, and the capacitance value of each of the capacitance elements C1 to C8 changes. This change in capacitance value is detected by the detection element 70 as a displacement occurring in the flexure bodies 30A to 30D. In this case, the change in capacitance value of each of the capacitance elements C1 to C8 may differ. Therefore, the detection circuit 75 can detect the direction and magnitude of the force or moment acting on the force receiving body 20 based on the change in capacitance value of each of the capacitance elements C1 to C8 detected by the detection element 70.

[0114] Here, first, using the first strain body 30A as an example, we will explain the changes in the capacitance values ​​of the first capacitance element C1 and the second capacitance element C2 when a force Fx in the X-axis direction, a force Fy in the Y-axis direction, and a force Fz in the Z-axis direction are applied.

[0115] (When +Fx is applied) When a force Fx acts on the first flexure body 30A in the X-axis direction positive side, the tilting structure 31 of the first flexure body 30A elastically deforms as shown in Fig. 8. More specifically, the first tilting portions 35L, 35R and the first deformation portions 36 of the tilting structure 31 are displaced in the X-axis direction positive side, and mainly the pair of third deformation portions 39 of the tilting structure 31 elastically deform. As a result, the first tilting opposing surfaces 35a of the first tilting portions 35L, 35R and the second tilting opposing surfaces 37a of the corresponding second tilting portions 37L, 37R are tilted.

[0116] In this case, the first tilting opposing surface 35a of the first tilting portion 35L arranged on the X-axis direction negative side and the second tilting opposing surface 37a of the second tilting portion 37L arranged on the X-axis direction negative side are interlocked. The first tilting opposing surface 35a of the first tilting portion 35L and the second tilting opposing surface 37a of the second tilting portion 37L rotate clockwise when viewed toward the Y-axis direction positive side (when viewed toward the paper surface of FIG. 8) and tilt in the same direction. The first displacement body 50 connected to the first tilting portion 35L tilts in the same way as the first tilting opposing surface 35a and rotates clockwise when viewed toward the Y-axis direction positive side. As a result, the first displacement portion 54 is displaced toward the Z-axis direction negative side. Therefore, the second displacement electrode substrate Ed2 approaches the second fixed electrode substrate Ef2, and the inter-electrode distance (distance in the Z-axis direction) between the second displacement electrode substrate Ed2 and the second fixed electrode substrate Ef2 decreases. As a result, the capacitance value of the second capacitance element C2 increases.

[0117] On the other hand, the first tilting opposing surface 35a of the first tilting portion 35R arranged on the X-axis direction positive side and the second tilting opposing surface 37a of the second tilting portion 37R arranged on the X-axis direction positive side are interlocked. The first tilting opposing surface 35a of the first tilting portion 35R and the second tilting opposing surface 37a of the second tilting portion 37R rotate clockwise when viewed toward the Y-axis direction positive side and tilt in the same direction. The second displacement body 60 connected to the second tilting portion 37R tilts in the same way as the second tilting opposing surface 37a and rotates clockwise when viewed toward the Y-axis direction positive side. This causes the second displacement portion 64 to displace toward the Z-axis direction positive side. Therefore, the first displacement electrode substrate Ed1 moves away from the first fixed electrode substrate Ef1, and the inter-electrode distance between the first displacement electrode substrate Ed1 and the first fixed electrode substrate Ef1 increases. Therefore, the capacitance value of the first capacitance element C1 decreases.

[0118] (When -Fx is applied) When a force Fx acts on the first strain body 30A in the negative X-axis direction, a phenomenon occurs that is opposite to that shown in Fig. 8, although this is not shown in the figure. That is, the capacitance value of the second capacitance element C2 decreases, and the capacitance value of the first capacitance element C1 increases.

[0119] (When +Fy is applied) When a force Fy acts on the first flexure body 30A in the Y-axis direction positive side, the first flexure body 30A elastically deforms so as to rotate around the X-axis, i.e., counterclockwise toward the X-axis direction positive side, as shown in Fig. 9. This causes the first flexure body 30A to elastically deform so as to tilt as a whole with respect to the Z-axis direction, so that the first connection portion 32 of the first flexure body 30A falls toward the Y-axis direction positive side. Therefore, the first flexure body 30A elastically deforms so as to bend in the thickness direction.

[0120] In this case, the first tilting opposing surface 35a of each of the first tilting parts 35L and 35R rotates and tilts counterclockwise when viewed toward the X-axis direction positive side. The first displacement body 50 connected to the first tilting part 35L tilts in the same manner as the first tilting opposing surface 35a and rotates counterclockwise when viewed toward the X-axis direction positive side. This causes the first displacement part 54 to displace to the Z-axis direction positive side. Therefore, the second displacement electrode substrate Ed2 moves away from the second fixed electrode substrate Ef2, and the inter-electrode distance between the second displacement electrode substrate Ed2 and the second fixed electrode substrate Ef2 increases. Therefore, the capacitance value of the second capacitance element C2 decreases.

[0121] Similarly, the second tilting opposing surface 37a of each of the second tilting parts 37L and 37R rotates and tilts counterclockwise when viewed toward the X-axis direction positive side. Although not shown, the second displacement body 60 connected to the second tilting part 37R tilts in the same manner as the second tilting opposing surface 37a and rotates counterclockwise when viewed toward the X-axis direction positive side. This causes the second displacement part 64 to displace to the Z-axis direction positive side. Therefore, the first displacement electrode substrate Ed1 moves away from the first fixed electrode substrate Ef1, and the inter-electrode distance between the first displacement electrode substrate Ed1 and the first fixed electrode substrate Ef1 increases. Therefore, the capacitance value of the first capacitance element C1 decreases.

[0122] (When -Fy is applied) When a force Fy acts on the first strain body 30A in the negative Y-axis direction, a phenomenon occurs that is opposite to that shown in Fig. 9, although this is not shown in the figure. That is, the capacitance value of the second capacitance element C2 increases, and the capacitance value of the first capacitance element C1 increases.

[0123] (When +Fz is applied) When a force Fz acts on the first strain body 30A in the Z-axis direction positive direction, the tilting structure 31 elastically deforms as shown in Fig. 10A. More specifically, the first connection portion 32 is displaced in the Z-axis direction positive direction, and mainly the pair of first deformation portions 36, the pair of second deformation portions 38, and the pair of third deformation portions 39 of the tilting structure 31 elastically deform. As a result, the first tilting opposing surfaces 35a of the first tilting portions 35L, 35R and the second tilting opposing surfaces 37a of the corresponding second tilting portions 37L, 37R are tilted.

[0124] In this case, the first tilting opposing surface 35a of the first tilting portion 35L and the second tilting opposing surface 37a of the second tilting portion 37L are linked and tilt in different directions. The first displacement body 50 connected to the first tilting portion 35L is tilted in the same manner as the first tilting opposing surface 35a, and the first displacement portion 54 is displaced to the positive side in the Z-axis direction. As a result, the second displacement electrode substrate Ed2 moves away from the second fixed electrode substrate Ef2, and the inter-electrode distance between the second displacement electrode substrate Ed2 and the second fixed electrode substrate Ef2 increases. As a result, the electrostatic capacitance value of the second capacitance element C2 decreases.

[0125] More specifically, when the first displacement body 50 is inclined in the same manner as the first tilting opposing surface 35a, it rotates counterclockwise when viewed toward the Y-axis direction positive side. The counterclockwise rotation of the first displacement body 50 is one displacement component that displaces the first displacement part 54 in the Z-axis direction. When a force Fz acts on the Z-axis direction positive side, the first tilting opposing surface 35a displaces to the Z-axis direction positive side. The displacement of the first tilting opposing surface 35a to the Z-axis direction positive side is another displacement component that displaces the first displacement part 54 in the Z-axis direction. Since these two displacement components both contribute to the displacement of the first displacement part 54 to the Z-axis direction positive side, the first displacement part 54 displaces to the Z-axis direction positive side. The displacement amount (absolute value) of the first displacement part 54 to the Z-axis direction positive side is greater than the displacement amount (absolute value) of the second displacement part 64 to be described later to the Z-axis direction negative side. Therefore, the amount of decrease in the capacitance value of the second capacitance element C2 becomes larger than the amount of increase in the capacitance value of the first capacitance element C1.

[0126] On the other hand, the first tilting opposing surface 35a of the first tilting portion 35R and the second tilting opposing surface 37a of the second tilting portion 37R are linked and tilted in different directions. The second displacement body 60 connected to the second tilting portion 37R is tilted in the same manner as the second tilting opposing surface 37a, and the second displacement portion 64 is displaced to the negative side in the Z-axis direction. As a result, the first displacement electrode substrate Ed1 approaches the first fixed electrode substrate Ef1, and the inter-electrode distance between the first displacement electrode substrate Ed1 and the first fixed electrode substrate Ef1 decreases. Therefore, the capacitance value of the first capacitance element C1 increases.

[0127] More specifically, when the second displacement body 60 is inclined in the same manner as the second tilting opposing surface 37a, it rotates counterclockwise when viewed toward the Y-axis direction positive side. The counterclockwise rotation of the second displacement body 60 is one displacement component that displaces the second displacement portion 64 in the Z-axis direction. In addition, when a force Fz acts on the Z-axis direction positive side, the second tilting opposing surface 37a displaces to the Z-axis direction positive side. The displacement of the second tilting opposing surface 37a to the Z-axis direction positive side is another displacement component that displaces the second displacement portion 64 in the Z-axis direction. The displacement component due to the counterclockwise rotation of the second displacement body 60 contributes to the displacement of the second displacement portion 64 to the Z-axis direction negative side, while the displacement of the second tilting opposing surface 37a to the Z-axis direction positive side contributes to the displacement of the second displacement portion 64 to the Z-axis direction positive side. However, the displacement amount (absolute value) of the displacement component due to the counterclockwise rotation of the second displacement body 60 is larger than the displacement amount (absolute value) of the displacement component due to the displacement of the second tilting opposing surface 37a toward the positive side in the Z axis direction. Therefore, the second displacement part 64 is displaced toward the negative side in the Z axis direction. And the displacement amount (absolute value) of the second displacement part 64 toward the negative side in the Z axis direction is smaller than the displacement amount (absolute value) of the first displacement part 54 toward the positive side in the Z axis direction. Therefore, the increase in the capacitance value of the first capacitance element C1 is smaller than the decrease in the capacitance value of the second capacitance element C2.

[0128] Here, the second displacement body 60 according to the present embodiment is configured such that the second displacement portion 64 is displaced to the negative side in the Z axis direction when a force Fz toward the positive side in the Z axis direction acts on it. That is, the X axis direction dimension Lx2 (see FIG. 5) of the second displacement body 60 may be set so that the amount of displacement of the displacement component due to the counterclockwise rotation of the second displacement body 60 is larger than the amount of displacement of the displacement component due to the displacement of the second tilting opposing surface 37a toward the positive side in the Z axis direction. The first displacement body 50 may be configured to be symmetrical with the second displacement body 60. That is, the X axis direction dimension Lx1 (see FIG. 5) of the first displacement body 50 may be equal to the X axis direction dimension Lx2 of the second displacement body 60.

[0129] (When -Fz is applied) When a force Fz acts on the first strain body 30A in the negative Z-axis direction, the tilting structure 31 elastically deforms as shown in Fig. 10B. More specifically, the first connection portion 32 is displaced to the negative Z-axis direction, and mainly the pair of first deformation portions 36, the pair of second deformation portions 38, and the pair of third deformation portions 39 of the tilting structure 31 elastically deform. As a result, the first tilting opposing surfaces 35a of the first tilting portions 35L, 35R and the second tilting opposing surfaces 37a of the corresponding second tilting portions 37L, 37R are tilted.

[0130] In this case, the first tilting opposing surface 35a of the first tilting portion 35L and the second tilting opposing surface 37a of the second tilting portion 37L are linked and tilted in different directions. The first displacement body 50 connected to the first tilting portion 35L is tilted in the same manner as the first tilting opposing surface 35a, and the first displacement portion 54 is displaced to the negative side in the Z-axis direction. As a result, the second displacement electrode substrate Ed2 approaches the second fixed electrode substrate Ef2, and the inter-electrode distance between the second displacement electrode substrate Ed2 and the second fixed electrode substrate Ef2 decreases. Therefore, the electrostatic capacitance value of the second capacitance element C2 increases.

[0131] More specifically, when the first displacement body 50 is inclined in the same manner as the first tilting opposing surface 35a, the first displacement body 50 rotates clockwise when viewed toward the Y-axis positive side. The clockwise rotation of the first displacement body 50 is one displacement component that displaces the first displacement portion 54 in the Z-axis direction. When a force Fz acts on the Z-axis negative side, the first tilting opposing surface 35a displaces to the Z-axis negative side. The displacement of the first tilting opposing surface 35a to the Z-axis negative side is another displacement component that displaces the first displacement portion 54 in the Z-axis direction. Since these two displacement components both contribute to the displacement of the first displacement portion 54 to the Z-axis negative side, the first displacement portion 54 displaces to the Z-axis negative side. The displacement amount (absolute value) of the first displacement portion 54 to the Z-axis negative side is greater than the displacement amount (absolute value) of the second displacement portion 64 to be described later to the Z-axis positive side. Therefore, the increase in the capacitance value of the second capacitance element C2 is greater than the decrease in the capacitance value of the first capacitance element C1.

[0132] On the other hand, the first tilting opposing surface 35a of the first tilting portion 35R and the second tilting opposing surface 37a of the second tilting portion 37R are linked and tilted in different directions. The second displacement body 60 connected to the second tilting portion 37R is tilted in the same manner as the second tilting opposing surface 37a, and the second displacement portion 64 is displaced to the positive side in the Z-axis direction. As a result, the first displacement electrode substrate Ed1 moves away from the first fixed electrode substrate Ef1, and the inter-electrode distance between the first displacement electrode substrate Ed1 and the first fixed electrode substrate Ef1 increases. As a result, the capacitance value of the first capacitance element C1 decreases.

[0133] More specifically, when the second displacement body 60 is inclined in the same manner as the second tilting opposing surface 37a, the second displacement body 60 rotates clockwise when viewed toward the Y-axis positive side. The clockwise rotation of the second displacement body 60 is one displacement component that displaces the second displacement portion 64 in the Z-axis direction. In addition, when a force Fz acts on the Z-axis negative side, the second tilting opposing surface 37a displaces to the Z-axis negative side. The displacement of the second tilting opposing surface 37a to the Z-axis negative side is another displacement component that displaces the second displacement portion 64 in the Z-axis direction. The displacement component due to the clockwise rotation of the second displacement body 60 contributes to the displacement of the second displacement portion 64 in the Z-axis positive side, while the displacement of the second tilting opposing surface 37a to the Z-axis negative side contributes to the displacement of the second displacement portion 64 in the Z-axis negative side. However, the displacement amount (absolute value) of the displacement component due to the clockwise rotation of the second displacement body 60 is larger than the displacement amount (absolute value) of the displacement component due to the displacement of the second tilting opposing surface 37a to the negative side in the Z axis direction. Therefore, the second displacement part 64 is displaced to the positive side in the Z axis direction. And the displacement amount (absolute value) of the second displacement part 64 to the positive side in the Z axis direction is smaller than the displacement amount (absolute value) of the first displacement part 54 to the positive side in the Z axis direction. Therefore, the decrease in the capacitance value of the first capacitance element C1 is smaller than the increase in the capacitance value of the second capacitance element C2.

[0134] Here, the second displacement body 60 according to the present embodiment is configured such that the second displacement part 64 is displaced to the Z-axis positive side when a force Fz is applied to the Z-axis negative side. That is, the X-axis dimension Lx2 (see FIG. 5) of the second displacement body 60 may be set so that the amount of displacement of the displacement component due to the clockwise rotation of the second displacement body 60 is larger than the amount of displacement of the displacement component due to the displacement of the second tilting opposing surface 37a to the Z-axis negative side.

[0135] Here, changes in the electrostatic capacitance value of each of the capacitance elements C1 and C2 provided in the first flexure body 30A shown in Fig. 4 are shown in Fig. 11. Fig. 11 is a table showing changes in the electrostatic capacitance value of each of the capacitance elements C1 and C2 in the first flexure body 30A of Fig. 4.

[0136] FIG. 11 shows the change in capacitance value of the capacitance elements C1 and C2 with respect to a force Fx in the X-axis direction, a force Fy in the Y-axis direction, and a force Fz in the Z-axis direction. A decrease in capacitance value is indicated by "- (minus)", and an increase in capacitance value is indicated by "+ (plus)". For example, "+" is shown for C1 in the row of Fx in the table shown in FIG. 11, which indicates that the capacitance value of the first capacitance element C1 increases when a force of +Fx is applied as described above. On the other hand, "-" is shown for C2 in the row of Fx in the table shown in FIG. 11, which indicates that the capacitance value of the second capacitance element C2 decreases when a force of +Fx is applied as described above. As described above, when a force Fz is applied, the amount of change in the capacitance value of the first capacitance element C1 is different from the amount of change in the capacitance value of the second capacitance element C2. However, for simplification, in FIG. 11, the change in capacitance value is simply indicated by a sign.

[0137] From the table shown in FIG. 11, in the force sensor 10 in which the force receiving body 20 and the fixed body 25 are connected only by the first strain body 30A, the forces Fx, Fy, and Fz acting on the force receiving body 20 can be calculated by the following formulas. In the following formulas, for convenience, the force or moment and the change in capacitance value are connected with "=". However, since the force or moment and the capacitance value are different physical quantities, the force is actually calculated by converting the change in capacitance value. C1 and C2 in the following formulas indicate the change in capacitance value in each capacitance element.

number

number

number

[0138] 11, in the force sensor 10 in which the force receiving body 20 and the fixed body 25 are connected only by the first strain generating body 30A, the force Fx in the X-axis direction and the force Fz in the Z-axis direction can both be detected by the difference between the capacitance value of the first capacitance element C1 and the capacitance value of the second capacitance element C2. In particular, for the force Fz, as shown in the above formula (3), the output value of the force Fz can be calculated by the difference between the amount of change in the capacitance value of the first capacitance element C1 and the amount of change in the capacitance value of the second capacitance element C2. Even if the capacitance value of the first capacitance element C1 and the capacitance value of the second capacitance element C2 each include an influence due to disturbances such as noise or ambient temperature, the influence can be offset by the difference in the above formula (3).

[0139] For example, in the force sensor shown in Patent Document 1, when a force Fz in the positive Z-axis direction acts, the first capacitance element C1 and the second capacitance element C2 both decrease, and when a force Fz in the negative Z-axis direction acts, the first capacitance element C1 and the second capacitance element C2 both increase. In this case, the output value of the force Fz is calculated by adding the amount of change in the capacitance value of the first capacitance element C1 and the amount of change in the capacitance value of the second capacitance element C2. Therefore, the output value of the force Fz may include the influence of disturbances such as noise or ambient temperature.

[0140] In contrast, in the present embodiment, as described above, when the force Fz acts, one of the capacitance value of the first capacitance element C1 and the capacitance value of the second capacitance element C2 increases, and the other decreases. As a result, the output value of the force Fz can be calculated from the difference between the amount of change in the capacitance value of the first capacitance element C1 and the amount of change in the capacitance value of the second capacitance element C2. In this case, the influence of the disturbance described above can be offset. Therefore, the output value of the force Fz can be prevented from being influenced by the disturbance, and the force sensor 10 can have high performance.

[0141] Since Fx and Fz only have different signs, it is difficult to distinguish whether the detected force is Fx or Fz. Therefore, the force sensor 10 using only one first strain body 30A can be used when either one of the forces Fx and Fz and the force Fy in the Y-axis direction act. In this case, the force sensor 10 is a force sensor capable of detecting two-axis components.

[0142] Next, in the force sensor 10 shown in Fig. 7, changes in the capacitance value of each of the capacitance elements C1 to C8 when a force Fx in the X-axis direction, a force Fy in the Y-axis direction, a force Fz in the Z-axis direction, a moment Mx about the X-axis, a moment My about the Y-axis, and a moment Mz about the Z-axis are applied will be described with reference to Fig. 12. Fig. 12 is a table showing changes in the capacitance value of each capacitance element in the force sensor of Fig. 7.

[0143] (When +Fx is applied) First, a case where force Fx acts on force receiving body 20 in the X-axis direction positive direction will be described.

[0144] In this case, the first flexure body 30A elastically deforms in the same manner as the first flexure body 30A shown in Fig. 8, and the capacitance value of the first capacitance element C1 decreases while the capacitance value of the second capacitance element C2 increases. In this case, the decrease in the capacitance value of the first capacitance element C1 is relatively large, so C1 in the row of Fx in the table shown in Fig. 12 is marked "--". The increase in the capacitance value of the second capacitance element C2 is relatively large, so C2 in the row of Fx in the table shown in Fig. 12 is marked "++".

[0145] The second flexure body 30B elastically deforms in the opposite direction to the first flexure body 30A shown in FIG. 9. That is, the second flexure body 30B rotates around the Y axis, i.e., clockwise toward the Y axis direction positive side. This increases the capacitance value of the third capacitance element C3 and the capacitance value of the fourth capacitance element C4. However, the increase in the capacitance value of the third capacitance element C3 and the increase in the capacitance value of the fourth capacitance element C4 are negligibly small. For this reason, C3 and C4 in the row of Fx in the table shown in FIG. 12 are set to "0 (zero)".

[0146] The third flexure body 30C elastically deforms in the opposite direction to the first flexure body 30A shown in Fig. 8. That is, the capacitance value of the fifth capacitance element C5 increases and the capacitance value of the sixth capacitance element C6 decreases. In this case, the increase in the capacitance value of the fifth capacitance element C5 is relatively large, so C5 in the row of Fx in the table shown in Fig. 12 is marked with "++". The decrease in the capacitance value of the sixth capacitance element C6 is relatively large, so C6 in the row of Fx in the table shown in Fig. 12 is marked with "--".

[0147] The fourth flexure body 30D elastically deforms in the same manner as the first flexure body 30A shown in FIG. 9. That is, the fourth flexure body 30D rotates around the Y axis, i.e., clockwise toward the Y axis direction positive side. This causes the capacitance value of the seventh capacitance element C7 to decrease and the capacitance value of the eighth capacitance element C8 to decrease. However, the amount of decrease in the capacitance value of the seventh capacitance element C7 and the amount of decrease in the capacitance value of the eighth capacitance element C8 are negligibly small. For this reason, C7 and C8 in the row of Fx in the table shown in FIG. 12 are set to "0 (zero)".

[0148] (When +Fy is applied) Next, a case will be described where force Fy acts on force receiving body 20 in the Y-axis direction positive direction. In the following description as well, the symbols in the table of Fig. 12 are determined according to the change in capacitance value as described above.

[0149] The first flexure body 30A elastically deforms in the same manner as the first flexure body 30A shown in FIG. 9. That is, the first flexure body 30A rotates around the X-axis, i.e., counterclockwise toward the positive side in the X-axis direction. This causes the capacitance value of the first capacitance element C1 to decrease and the capacitance value of the second capacitance element C2 to decrease. However, the amount of decrease in the capacitance value of the first capacitance element C1 and the amount of decrease in the capacitance value of the second capacitance element C2 are negligibly small. For this reason, C1 and C2 in the row of Fx in the table shown in FIG. 12 are set to "0 (zero)".

[0150] The second flexure body 30B elastically deforms in the opposite direction to the first flexure body 30A shown in Fig. 9. That is, the capacitance value of the third capacitance element C3 decreases and the capacitance value of the fourth capacitance element C4 increases. In this case, the decrease in the capacitance value of the third capacitance element C3 is relatively large, so C3 in the row of Fy in the table shown in Fig. 12 is marked "--". The increase in the capacitance value of the fourth capacitance element C4 is relatively large, so C4 in the row of Fy in the table shown in Fig. 12 is marked "++".

[0151] The third flexure body 30C elastically deforms in the opposite direction to the first flexure body 30A shown in FIG. 9. That is, the third flexure body 30C rotates around the X-axis, i.e., counterclockwise toward the positive side in the X-axis direction. This increases the capacitance value of the fifth capacitance element C5 and the capacitance value of the sixth capacitance element C6. However, the increase in the capacitance value of the fifth capacitance element C5 and the increase in the capacitance value of the sixth capacitance element C6 are negligibly small. For this reason, C5 and C6 in the row of Fx in the table shown in FIG. 12 are set to "0 (zero)".

[0152] The fourth flexure body 30D elastically deforms in the same manner as the first flexure body 30A shown in Fig. 8. That is, the capacitance value of the seventh capacitance element C7 increases and the capacitance value of the eighth capacitance element C8 decreases. In this case, the increase in the capacitance value of the seventh capacitance element C7 is relatively large, so C7 in the row of Fy in the table shown in Fig. 12 is marked with "++". The decrease in the capacitance value of the eighth capacitance element C8 is relatively large, so C8 in the row of Fy in the table shown in Fig. 12 is marked with "--".

[0153] (When +Fz is applied) Next, a case will be described where force Fz acts on force receiving body 20 in the Z-axis direction positive direction. In the following description as well, the symbols in the table of FIG. 9 are determined according to the change in capacitance value as described above.

[0154] In this case, the first flexure body 30A elastically deforms in the same manner as the first flexure body 30A shown in Fig. 10A, and the capacitance value of the first capacitance element C1 increases and the capacitance value of the second capacitance element C2 decreases. In this case, the increase in the capacitance value of the first capacitance element C1 is relatively small, so C1 in the row of Fz in the table shown in Fig. 12 is marked with "+". The decrease in the capacitance value of the second capacitance element C2 is relatively large, so C2 in the row of Fz in the table shown in Fig. 12 is marked with "--".

[0155] The second flexure body 30B elastically deforms in the same manner as the first flexure body 30A shown in Fig. 10A, and the capacitance value of the third capacitance element C3 decreases and the capacitance value of the fourth capacitance element C4 increases. In this case, the decrease in the capacitance value of the third capacitance element C3 is relatively large, so C3 in the row of Fz in the table shown in Fig. 12 is marked "--". The increase in the capacitance value of the fourth capacitance element C4 is relatively small, so C4 in the row of Fz in the table shown in Fig. 12 is marked "+".

[0156] The third flexure body 30C elastically deforms in the same manner as the first flexure body 30A shown in Fig. 10A, and the capacitance value of the fifth capacitance element C5 increases and the capacitance value of the sixth capacitance element C6 decreases. In this case, the increase in the capacitance value of the fifth capacitance element C5 is relatively small, so C5 in the row of Fz in the table shown in Fig. 12 is marked with "+". The decrease in the capacitance value of the sixth capacitance element C6 is relatively large, so C6 in the row of Fz in the table shown in Fig. 12 is marked with "--".

[0157] The fourth flexure body 30D elastically deforms in the same manner as the first flexure body 30A shown in Fig. 10A, and the capacitance value of the seventh capacitance element C7 decreases and the capacitance value of the eighth capacitance element C8 increases. In this case, the decrease in the capacitance value of the seventh capacitance element C7 is relatively large, so C7 in the row of Fz in the table shown in Fig. 12 is marked "--". The increase in the capacitance value of the eighth capacitance element C8 is relatively small, so C8 in the row of Fz in the table shown in Fig. 12 is marked "+".

[0158] (When +Mx is applied) Next, a case will be described where a clockwise moment Mx (see FIG. 7) around the X-axis, i.e., toward the positive side in the X-axis direction, acts on force receiving body 20. In the following explanation as well, the symbols in the table of FIG. 12 are determined as described above according to the change in capacitance value.

[0159] In this case, the first strain body 30A is elastically deformed in the same manner as the first strain body 30A to which a force Fz directed toward the positive side in the Z-axis direction is applied as shown in FIG. 10A, and the capacitance value of the first capacitance element C1 increases and the capacitance value of the second capacitance element C2 decreases. In this case, as described above, the increase in the capacitance value of the first capacitance element C1 is smaller than the decrease in the capacitance value of the second capacitance element C2, and the increase in the capacitance value of the first capacitance element C1 is relatively small. For this reason, C1 in the row of Mx in the table shown in FIG. 12 is indicated as "+". Since the decrease in the capacitance value of the second capacitance element C2 is relatively large, C2 in the row of Mx in the table shown in FIG. 12 is indicated as "--".

[0160] In the second flexure body 30B, the central axis CL (see FIG. 4) of the tilting structure 31 is located at the center O of the force receiving body 20 in the Y-axis direction, so the elastic deformation of the second flexure body 30B is smaller than that of the first flexure body 30A and the third flexure body 30C. Here, for the sake of simplicity, it is assumed that the second flexure body 30B does not elastically deform. Therefore, the capacitance value of the third capacitance element C3 does not change, and the capacitance value of the fourth capacitance element C4 does not change either. C3 and C4 in the row of Mx in the table shown in FIG. 12 are set to "0 (zero)".

[0161] The third elastic body 30C is elastically deformed in the same manner as the first elastic body 30A to which the force Fz directed in the negative Z-axis direction is applied as shown in FIG. 10B, and the capacitance value of the fifth capacitance element C5 decreases and the capacitance value of the sixth capacitance element C6 increases. In this case, as described above, the decrease in the capacitance value of the first capacitance element C1 is smaller than the increase in the capacitance value of the second capacitance element C2, and the decrease in the capacitance value of the fifth capacitance element C5 is relatively small. For this reason, C5 in the row of Mx in the table shown in FIG. 12 is marked with "-". Since the increase in the capacitance value of the sixth capacitance element C6 is relatively large, C2 in the row of Mx in the table shown in FIG. 12 is marked with "++".

[0162] In the fourth flexure body 30D, the central axis CL (see FIG. 4) of the tilting structure 31 is located at the center O of the force receiving body 20 in the Y-axis direction, so the elastic deformation of the fourth flexure body 30D is smaller than those of the first flexure body 30A and the third flexure body 30C. Here, for the sake of simplicity, it is assumed that the fourth flexure body 30D does not elastically deform. Therefore, the capacitance value of the seventh capacitance element C7 does not change, and the capacitance value of the eighth capacitance element C8 does not change either. C7 and C8 in the row of Mx in the table shown in FIG. 12 are set to "0 (zero)".

[0163] (When +My is applied) Next, a case will be described where a moment My (see FIG. 7) around the Y-axis, i.e., clockwise toward the positive side in the Y-axis direction, acts on force receiving body 20. In the following explanation, the symbols in the table of FIG. 12 are determined as described above according to the change in capacitance value.

[0164] In this case, in the first flexure body 30A, the central axis CL (see FIG. 4) of the tilting structure 31 is located at the center O of the force receiving body 20 in the X-axis direction, so the elastic deformation of the first flexure body 30A is smaller than those of the second flexure body 30B and the fourth flexure body 30D. Here, for the sake of simplicity, it is assumed that the first flexure body 30A does not elastically deform. Therefore, the capacitance value of the first capacitance element C1 does not change, and the capacitance value of the second capacitance element C2 does not change either. C1 and C2 in the row of My in the table shown in FIG. 12 are set to "0 (zero)".

[0165] The second strain body 30B is elastically deformed in the same manner as the first strain body 30A to which a force Fz directed in the positive direction of the Z-axis direction is applied as shown in FIG. 10A, and the capacitance value of the third capacitance element C3 decreases and the capacitance value of the fourth capacitance element C4 increases. In this case, as described above, the decrease in the capacitance value of the third capacitance element C3 is greater than the increase in the capacitance value of the fourth capacitance element C4, and the decrease in the capacitance value of the third capacitance element C3 is relatively large. For this reason, C3 in the row of My in the table shown in FIG. 12 is indicated as "--". Since the increase in the capacitance value of the fourth capacitance element C4 is relatively small, C4 in the row of My in the table shown in FIG. 12 is indicated as "+".

[0166] In the third flexure body 30C, the central axis CL (see FIG. 4) of the tilting structure 31 is located at the center O of the force receiving body 20 in the X-axis direction, so the elastic deformation of the third flexure body 30C is smaller than those of the second flexure body 30B and the fourth flexure body 30D. Here, for the sake of simplicity, it is assumed that the third flexure body 30C does not elastically deform. Therefore, the capacitance value of the fifth capacitance element C5 does not change, and the capacitance value of the sixth capacitance element C6 does not change either. C5 and C6 in the row of My in the table shown in FIG. 12 are set to "0 (zero)".

[0167] The fourth elastic body 30D is elastically deformed in the same manner as the first elastic body 30A to which the force Fz directed in the negative Z-axis direction is applied as shown in FIG. 10B, and the capacitance value of the seventh capacitance element C7 increases and the capacitance value of the eighth capacitance element C8 decreases. In this case, as described above, the increase in the capacitance value of the seventh capacitance element C7 is greater than the decrease in the capacitance value of the eighth capacitance element C8, and the increase in the capacitance value of the seventh capacitance element C7 is relatively large. For this reason, C7 in the row of My in the table shown in FIG. 12 is indicated as "++". The decrease in the capacitance value of the eighth capacitance element C8 is relatively small, so C8 in the row of My in the table shown in FIG. 12 is indicated as "-".

[0168] (When +Mz is applied) Next, a case will be described where a clockwise moment Mz (see FIG. 7) around the Z axis, i.e., toward the positive side in the Z axis direction, acts on force receiving body 20. In the following explanation as well, the symbols in the table of FIG. 12 are determined as described above according to the change in capacitance value.

[0169] In this case, the first flexure body 30A is elastically deformed in the same manner as when a negative force Fx in the X-axis direction is applied. As a result, the first flexure body 30A is elastically deformed in the opposite direction to the first flexure body 30A shown in FIG. 8, the capacitance value of the first capacitance element C1 increases, and the capacitance value of the second capacitance element C2 decreases. In this case, the increase in the capacitance value of the first capacitance element C1 is relatively large, so C1 in the row of Mz in the table shown in FIG. 12 is marked with "++". The decrease in the capacitance value of the second capacitance element C2 is relatively large, so C2 in the row of Mz in the table shown in FIG. 12 is marked with "--".

[0170] The second flexure body 30B elastically deforms in the same manner as when a force Fy in the negative Y-axis direction is applied. As a result, the second flexure body 30B elastically deforms in the same manner as the first flexure body 30A shown in FIG. 8, the capacitance value of the third capacitance element C3 increases, and the capacitance value of the fourth capacitance element C4 decreases. In this case, the increase in the capacitance value of the third capacitance element C3 is relatively large, so C3 in the row of Mz in the table shown in FIG. 12 is marked with "++". The decrease in the capacitance value of the fourth capacitance element C4 is relatively large, so C4 in the row of Mz in the table shown in FIG. 12 is marked with "--".

[0171] The third flexure body 30C is elastically deformed in the same manner as when a force Fx in the positive X-axis direction is applied. As a result, the third flexure body 30C is elastically deformed in the opposite direction to the first flexure body 30A shown in FIG. 8, the capacitance value of the fifth capacitance element C5 increases, and the capacitance value of the sixth capacitance element C6 decreases. In this case, the increase in the capacitance value of the fifth capacitance element C5 is relatively large, so C5 in the row of Mz in the table shown in FIG. 12 is marked with "++". The decrease in the capacitance value of the sixth capacitance element C6 is relatively large, so C6 in the row of Mz in the table shown in FIG. 12 is marked with "--".

[0172] The fourth flexure body 30D elastically deforms in the same manner as when a force Fy in the positive Y-axis direction is applied. As a result, the fourth flexure body 30D elastically deforms in the same manner as the first flexure body 30A shown in FIG. 8, the capacitance value of the seventh capacitance element C7 increases, and the capacitance value of the eighth capacitance element C8 decreases. In this case, the increase in the capacitance value of the seventh capacitance element C7 is relatively large, so C7 in the row of Mz in the table shown in FIG. 12 is marked with "++". The decrease in the capacitance value of the eighth capacitance element C8 is relatively large, so C8 in the row of Mz in the table shown in FIG. 12 is marked with "--".

[0173] In this manner, when a change in the capacitance value of each of capacitance elements C1-C8 is detected, the direction and magnitude of the force or moment acting on force receiving body 20 are detected. Then, as shown in FIG. 12, the capacitance value of each of capacitance elements C1-C8 changes.

[0174] From the table shown in FIG. 12, forces Fx, Fy, Fz and moments Mx, My, Mz acting on force receiving body 20 can be calculated by the following formulas. This makes it possible to detect six-axis components of force. In the following formulas, for convenience, the force or moment and the amount of change in capacitance value are connected with "=". However, since the force or moment and the capacitance value are different physical quantities, the force or moment is actually calculated by converting the amount of change in capacitance value. C1 to C8 in the following formulas indicate the amount of change in capacitance value in each capacitance element.

number

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[0175] As described above, the force sensor 10 shown in FIG. 7 can detect the forces Fx, Fy, and Fz and the moments Mx, My, and Mz as shown in the above-mentioned formulas (4) to (9), and therefore can detect six-axis components of force. However, the number of axial components of force that the force sensor 10 can detect is not limited to six, and the number of axial components that can be detected is arbitrary depending on the number, structure, and shape of the strain bodies. The coefficients a1 to a8 included in the above-mentioned formulas (4) to (9) are coefficients indicating that the change amount (increase or decrease amount) of the capacitance value is relatively small. As described above, when the force Fz is applied, the change amount of the capacitance value of each of the capacitance elements C1 to C8 is different, so the capacitance with a relatively small change amount is multiplied by the coefficient. The coefficients a1 to a8 may be different from each other.

[0176] In particular, the output value of the force Fz can be calculated from the difference in the amount of change in the capacitance value of the two capacitance elements C1 to C8 of each of the strain bodies 30A to 30D, as shown in the above formula (6). This makes it possible to cancel out the influence of disturbances such as noise or ambient temperature, even if such influence is included, as described above. That is, although the formula (6) includes the coefficients a1 to a4, the output value of the force Fz is calculated from the difference in the amount of change in the capacitance value of the capacitance elements C1 to C8, so that the influence of disturbances can be at least partially cancelled out. This makes it possible to prevent the output value of the force Fz from being influenced by disturbances, and to improve the performance of the force sensor 10.

[0177] Since the coefficients a1 to a8 are included in the above-mentioned formulas (4) to (9), cross-axis sensitivity occurs in each axis component. For example, when a force Fz acts on the first strain body 30A in the Z-axis direction positive direction, the amount of change in the capacitance value of the first capacitance element C1 differs from the amount of change in the capacitance value of the second capacitance element C2. In this case, cross-axis sensitivity may occur with respect to the force Fz. The same applies to the other axis components.

[0178] However, even if cross-axis sensitivity occurs, a correction calculation can be performed by calculating the inverse matrix of the cross-axis sensitivity matrix and multiplying the output (characteristic matrix) of the force sensor by this inverse matrix. As a result, the cross-axis sensitivity can be reduced to a level where the occurrence of the cross-axis sensitivity can be ignored.

[0179] Thus, according to this embodiment, the strain body 30A includes the first displacement portion 54 and the second displacement portion 64 that are displaced in opposite directions in the Z-axis direction when the force receiving body 20 receives the force Fz in the Z-axis direction. This makes it possible to increase one of the capacitance values ​​of the first capacitance element C1 and the second capacitance element C2, and to decrease the other. In this case, an output value indicating the magnitude of the force Fz in the Z-axis direction can be calculated based on the difference between the amount of change in the capacitance value of the first capacitance element C1 and the amount of change in the capacitance value of the second capacitance element C2. This makes it possible to prevent the output value of the force Fz from being affected by disturbances such as noise or ambient temperature, and to improve the detection accuracy of the force sensor 10. As a result, the force sensor 10 can have high performance.

[0180] According to this embodiment, the first tilting parts 35L and 35R of the tilting structure 31 are connected to the force receiving body 20 via the first connecting part 32, and the second tilting parts 37L and 37R are connected to the fixed body 25 via the second connecting part 33. The first displacement part 54 of the first flexure body 30A is connected to the first tilting part 35L arranged on one side in the X-axis direction with respect to the first connecting part 32. The second displacement part 64 of the first flexure body 30A is connected to the second tilting part 37R arranged on the other side in the X-axis direction with respect to the second connecting part 33. This makes it possible to tilt the first displacement body 50 and the second displacement body 60 when a force Fz in the Z-axis direction acts. In this case, one of the first displacement part 54 and the second displacement part 64 can be displaced to the positive side in the Z-axis direction, and the other of the first displacement part 54 and the second displacement part 64 can be displaced to the negative side in the Z-axis direction. Therefore, one of the capacitance value of the first capacitance element C1 and the capacitance value of the second capacitance element C2 can be increased and the other can be decreased. As a result, an output value indicating the magnitude of the force Fz can be calculated from the difference between the amount of change in the capacitance value of the first capacitance element C1 and the amount of change in the capacitance value of the second capacitance element C2.

[0181] Further, according to the present embodiment, the first displacement portion 54 is connected to the first tilting portion 35L arranged on the negative side in the X-axis direction with respect to the first connection portion 32, and is arranged on the side of the other first tilting portion 35R with respect to the first tilting portion 35L. This allows the first displacement portion 54 to be arranged on the positive side in the X-axis direction with respect to the corresponding first tilting portion 35L, and prevents the first displacement portion 54 from being arranged on the outside in the X-axis direction with respect to the tilting structure 31. Similarly, the second displacement portion 64 is connected to the second tilting portion 37R arranged on the positive side in the X-axis direction with respect to the second connection portion 33, and is arranged on the side of the other second tilting portion 37L with respect to the second tilting portion 37R. This allows the second displacement portion 64 to be arranged on the negative side in the X-axis direction with respect to the corresponding second tilting portion 37R, and prevents the second displacement portion 64 from being arranged on the outside in the X-axis direction with respect to the tilting structure 31. As a result, it is possible to improve space efficiency and to reduce the size of the force sensor 10.

[0182] According to the present embodiment, the first arm 53 connecting the first displacement portion 54 to the first tilting portion 35L extends in the X-axis direction from the corresponding first tilting portion 35L toward the other first tilting portion 35R. That is, the first arm 53 extends from the first tilting portion 35L toward the X-axis positive side. This allows the Z-axis displacement of the first displacement portion 54 to be increased when the first tilting portion 35L is tilted. Similarly, the second arm 63 connecting the second displacement portion 64 to the second tilting portion 37R extends in the X-axis direction from the corresponding second tilting portion 37R toward the other second tilting portion 37L. That is, the second arm 63 extends from the second tilting portion 37R toward the X-axis negative side. This allows the Z-axis displacement of the second displacement portion 64 to be increased when the second tilting portion 37R is tilted. This allows the detection sensitivity to be increased, and the reliability of the force sensor 10 to be improved.

[0183] According to this embodiment, the first arm 53 is attached to the first tilting facing surface 35a of the corresponding first tilting portion 35L, which faces the force receiving body 20, via the first connecting portion 51. This allows the first displacement portion 54 to be displaced in the Z-axis direction when the first tilting portion 35L is tilted. Similarly, the second arm 63 is attached to the second tilting facing surface 37a of the corresponding second tilting portion 37R, which faces the fixed body 25, via the second connecting portion 61. This allows the second displacement portion 64 to be displaced in the Z-axis direction when the second tilting portion 37R is tilted.

[0184] Moreover, according to the present embodiment, the first displacement portion 54 and the second displacement portion 64 are disposed on one side of the tilting structure 31 in the Y-axis direction. This makes it possible to improve space efficiency and reduce the size of the force sensor 10.

[0185] According to this embodiment, each first deformation portion 36 of the tilting structure 31 connects the corresponding first tilting portion 35L, 35R to the first connection portion 32, and each second deformation portion 38 of the tilting structure 31 connects the corresponding second tilting portion 37L, 37R to the second connection portion 33. The Z-axis direction dimension t1 of the first deformation portion 36 is smaller than the Z-axis direction dimension t2 of the first tilting portions 35L, 35R, and the Z-axis direction dimension t3 of the second deformation portion 38 is smaller than the Z-axis direction dimension t4 of the second tilting portions 37L, 37R. As a result, when a force Fz in the Z-axis direction is applied, the first deformation portion 36 and the second deformation portion 38 can be elastically deformed, and the first tilting portions 35L, 35R and the second tilting portions 37L, 37R can be tilted.

[0186] According to this embodiment, the first deformation portion 36 includes a first opposing surface 36a facing the force receiving body 20, and the first opposing surface 36a is disposed closer to the fixed body 25 than the first tilting opposing surface 35a of the first tilting portions 35L and 35R facing the force receiving body 20. This allows the first notch 40 to be formed between the first connection portion 32 and each of the first tilting portions 35L and 35R. Therefore, when a force Fz in the Z-axis direction is applied, it is possible to easily tilt each of the first tilting portions 35L and 35R. Similarly, the second deformation portion 38 includes a second opposing surface 38a facing the fixed body 25, and the second opposing surface 38a is disposed closer to the force receiving body 20 than the second tilting opposing surface 37a of the second tilting portions 37L and 37R facing the fixed body 25. This allows the second cutouts 41 to be formed between the second connection portion 33 and each of the second tilting portions 37L, 37R. Therefore, when a force Fz in the Z-axis direction is applied, the second tilting portions 37L, 37R can be easily tilted.

[0187] According to this embodiment, the first tilting portions 35L, 35R and the corresponding second tilting portions 37L, 37R are connected by the third deformation portion 39. The X-axis dimension t5 of the third deformation portion 39 is smaller than the X-axis dimension t6 of the first tilting portions 35L, 35R and smaller than the X-axis dimension t7 of the second tilting portions 37L, 37R. As a result, when a force Fz in the Z-axis direction acts, the third deformation portions 39 are elastically deformed, so that the first tilting portions 35L, 35R and the corresponding second tilting portions 37L, 37R can be tilted in opposite directions. In this case, one of the first displacement portion 54 and the second displacement portion 64 can be displaced to the positive side in the Z-axis direction, and the other of the first displacement portion 54 and the second displacement portion 64 can be displaced to the negative side in the Z-axis direction.

[0188] According to the present embodiment, the first capacitance element C1 of the first flexure body 30A includes a first displacement electrode substrate Ed1 provided on one of the first displacement portion 54 and the second displacement portion 64, and a first fixed electrode substrate Ef1 facing the first displacement electrode substrate Ed1. This allows the first capacitance element C1 to detect a change in capacitance value due to the displacement of one of the first displacement portion 54 and the second displacement portion 64 in the Z-axis direction. The second capacitance element C2 of the first flexure body 30A includes a second displacement electrode substrate Ed2 provided on the other of the first displacement portion 54 and the second displacement portion 64, and a second fixed electrode substrate Ef2 facing the second displacement electrode substrate Ed2. This allows the second capacitance element C2 to detect a change in capacitance value due to the displacement of the other of the first displacement portion 54 and the second displacement portion 64 in the Z-axis direction.

[0189] Furthermore, according to this embodiment, the first fixed electrode substrate Ef1 and the second fixed electrode substrate Ef2 are supported by the fixed body 25. This makes it possible to improve the detection accuracy of the displacement of the first displacement electrode substrate Ed1 in the Z-axis direction, and also to improve the detection accuracy of the displacement of the second displacement electrode substrate Ed2 in the Z-axis direction.

[0190] Furthermore, according to this embodiment, the first fixed electrode substrate Ef1 is supported by the fixed body 25 via the second pedestal 27, and the second fixed electrode substrate Ef2 is supported by the fixed body 25 via the first pedestal 26. This allows the first fixed electrode substrate Ef1 to be brought closer to the first displaceable electrode substrate Ed1, improving the detection accuracy of the displacement of the first displaceable electrode substrate Ed1. Similarly, the second fixed electrode substrate Ef2 can be brought closer to the second displaceable electrode substrate Ed2, improving the detection accuracy of the displacement of the second displaceable electrode substrate Ed2.

[0191] According to the present embodiment, the first flexure body 30A is disposed on the Y-axis direction positive side with respect to the center O of the force receiving body 20, the second flexure body 30B is disposed on the X-axis direction negative side, the third flexure body 30C is disposed on the Y-axis direction negative side, and the fourth flexure body 30D is disposed on the X-axis direction positive side. The second direction of the first flexure body 30A and the third flexure body 30C is the X-axis direction, and the second direction of the second flexure body 30B and the fourth flexure body 30D is the Y-axis direction. This allows the first flexure body 30A to the fourth flexure body 30D to be disposed in a ring shape with respect to the center O of the force receiving body 20 when viewed in the Z-axis direction. Also, the first flexure body 30A to the fourth flexure body 30D can be disposed evenly around the center O of the force receiving body 20. This allows the detection accuracy of a force or moment in any direction to be improved, and the detection accuracy of a force or moment to be suppressed from being reduced depending on the direction of the force or the direction of the moment.

[0192] Furthermore, according to this embodiment, the first displacement portion 54 and the second displacement portion 64 of each of the flexure bodies 30A to 30D are disposed closer to the center of the force receiving body 20 than the corresponding tilting structure 31. This improves space efficiency and allows the force sensor 10 to be made smaller. Furthermore, the tilting structure 31 of each of the flexure bodies 30A to 30D can be disposed on the opposite side of the center O of the force receiving body 20 than the corresponding first displacement portion 54 and second displacement portion 64. This allows space to be secured closer to the center of the force receiving body 20. In this case, through holes (not shown) can be formed in the center of the force receiving body 20 and the center of the fixed body 25, allowing a force sensor with through holes to be constructed.

[0193] (Variation 1) In the above-described embodiment, an example has been described in which the fixed electrode substrates Ef1, Ef2 are fixed to the fixed body 25 via the pedestals 26, 27. However, the embodiment is not limited to this. For example, as shown in Fig. 13, the fixed electrode substrates Ef1, Ef2 may be fixed directly to the fixed body 25 without the pedestals 26, 27. Fig. 13 is a front view showing a modified example of the first flexure body 30A of Fig. 4.

[0194] For example, as shown in FIG. 13, the Z-axis direction position of the first displacement portion 54 of the first strain body 30A may be disposed at a position closer to the fixed body 25 than the Z-axis direction position of the first displacement portion 54 shown in FIG. 4. In this case, the first extension portion 52 of the first displacement body 50 may be longer than the first extension portion 52 shown in FIG. 4. Similarly, for example, the Z-axis direction position of the second displacement portion 64 may be disposed at a position closer to the fixed body 25 than the Z-axis direction position of the second displacement portion 64 shown in FIG. 4. In this case, the second extension portion 62 of the second displacement body 60 may be shorter than the second extension portion 62 shown in FIG. 4. According to the modified example shown in FIG. 13, the pedestals 26 and 27 shown in FIG. 4 can be eliminated, and the number of parts can be reduced. The same applies to the second strain body 30B to the fourth strain body 30D and each detection element 70 shown in FIG. 13.

[0195] (Variation 2) In the above-described embodiment, the first opposing surface 36a of the first deformation portion 36 and the second opposing surface 38a of the second deformation portion 38 are each formed flat, and the first rectangular cutout portion 40 and the second rectangular cutout portion 41 are each formed flat. However, the embodiment is not limited to this. For example, as shown in FIG. 14, the first opposing surface 36a and the second opposing surface 38a may each be formed curved. FIG. 14 is a front view showing another modified example of the first flexure body 30A of FIG. 4.

[0196] As shown in FIG. 14, the first opposing surface 36a of the first flexure body 30A may be curved so as to expand in a direction toward the fixed body 25. The first cutout 40 may be formed from the first deformation portion 36 to a part of the first connection portion 32, or the part of the first connection portion 32 from the first deformation portion 36 to the first deformation portion 36 may be cut out in a continuous and curved shape. The first cutout 40 may be formed in an arc shape. Similarly, the second opposing surface 38a may be curved so as to expand in a direction toward the force receiving body 20. The second cutout 41 may be formed from the second deformation portion 38 to a part of the second connection portion 33, or the part of the second connection portion 33 from the second deformation portion 38 to the second deformation portion 38 may be cut out in a continuous and curved shape. The second cutout 41 may be formed in an arc shape.

[0197] 14, it is possible to prevent corners that cause stress concentration from being formed at both ends of the first opposing surface 36a in the X-axis direction. Similarly, it is possible to prevent corners that cause stress concentration from being formed at both ends of the second opposing surface 38a in the X-axis direction. Therefore, when a force or moment acts on the force receiving body 20, it is possible to prevent stress concentration from occurring in the tilting structure 31, and it is possible to improve the reliability of the force sensor 10.

[0198] In the example shown in FIG. 14, the third opposing surface 39a may be formed in a curved shape. The third opposing surface 39a may be curved so as to expand in the opposite direction to the third opposing surface 39a of the other third deformation portion 39. This can prevent corners that concentrate stress from being formed at both ends of the third opposing surface 39a in the Z-axis direction. Therefore, when a force or moment acts on the force receiving body 20, stress concentration can be prevented from occurring in the tilting structure 31, and the reliability of the force sensor 10 can be improved. As shown in FIG. 14, the third opposing surface 39a may be formed in a semicircular arc shape when viewed in the Y-axis direction.

[0199] 14, the Z-axis dimension Lz2 of the second connecting portion 33 may be smaller than the Z-axis dimension Lz1 of the first connecting portion 32. In this case, the Z-axis dimension of the pedestals 26, 27 for fixing the fixed electrode substrates Ef1, Ef2 can be reduced.

[0200] The configuration of the first flexure body 30A shown in FIG. 14 may be similarly applied to the second flexure body 30B to the fourth flexure body 30D.

[0201] (Variation 3) In the above-described embodiment, an example has been described in which the first displacement portion 54 of the first flexure body 30A is disposed on the negative side in the X-axis direction with respect to the central axis CL of the tilting structure 31 of the first flexure body 30A, and the second displacement portion 64 of the first flexure body 30A is disposed on the positive side in the X-axis direction with respect to the central axis CL. In the above-described embodiment, an example has been described in which the first displacement portion 54 of the third flexure body 30C is disposed on the positive side in the X-axis direction with respect to the central axis CL of the tilting structure 31 of the third flexure body 30C, and the second displacement portion 64 of the third flexure body 30C is disposed on the negative side in the X-axis direction with respect to the central axis CL. However, the embodiment is not limited to this.

[0202] For example, as shown in Fig. 15, the first displacement portion 54 of the first flexure body 30A may be arranged on the X-axis direction positive side with respect to the central axis CL of the tilting structure 31 of the first flexure body 30A, and the second displacement portion 64 of the first flexure body 30A may be arranged on the X-axis direction negative side with respect to the central axis CL. The first displacement portion 54 of the third flexure body 30C may be arranged on the X-axis direction negative side with respect to the central axis CL of the tilting structure 31 of the third flexure body 30C, and the second displacement portion 64 of the third flexure body 30C may be arranged on the X-axis direction positive side with respect to the central axis CL. As shown in Fig. 15, the first displacement portion 54 and the second displacement portion 64 of each of the flexure bodies 30A to 30D may be arranged alternately in the circumferential direction.

[0203] The capacitance values ​​of the capacitance elements C1 to C8 of the force sensor 10 shown in FIG. 15 change as shown in FIG. 16. The change in the capacitance value of the first capacitance element C1 shown in FIG. 16 is opposite to the change in the capacitance value of the first capacitance element C1 shown in FIG. 12. The change in the capacitance value of the second capacitance element C2 shown in FIG. 16 is opposite to the change in the capacitance value of the second capacitance element C2 shown in FIG. 12. The change in the capacitance value of the fifth capacitance element C5 shown in FIG. 16 is opposite to the change in the capacitance value of the fifth capacitance element C5 shown in FIG. 12. The change in the capacitance value of the sixth capacitance element C6 shown in FIG. 16 is opposite to the change in the capacitance value of the sixth capacitance element C6 shown in FIG. 12.

[0204] 16, forces Fx, Fy, Fz and moments Mx, My, Mz acting on force receiving body 20 can be calculated by the following equations. This makes it possible to detect six-axis components of the force.

number

number

number

number

number

number

[0205] As described above, the force sensor 10 shown in FIG. 15 can detect forces Fx, Fy, Fz and moments Mx, My, Mz as shown in the above-mentioned formulas (10) to (15), and therefore can detect six-axis components of force. However, the number of axial components of force that the force sensor 10 can detect is not limited to six, and the number of axial components that can be detected is arbitrary depending on the number, structure, and shape of the strain bodies. The coefficients b1 to b8 included in the above-mentioned formulas (10) to (15) are coefficients that indicate that the amount of change (increase or decrease) in the capacitance value is relatively small. The coefficients b1 to b8 can be different from each other.

[0206] In particular, in the force sensor 10 shown in FIG. 15, when the force Fz acts, the force Fz can be calculated based on the difference between the amount of change in the capacitance values ​​of the two capacitance elements C1 to C8 of each of the strain bodies 30A to 30D. As a result, even if the force Fz is affected by disturbances such as noise or ambient temperature, the effect can be offset as described above. Therefore, the output value of the force Fz can be prevented from being affected by disturbances, and the force sensor 10 can have high performance. That is, although the formula (12) includes the coefficients b1 to b4, the output value of the force Fz is calculated based on the difference between the amount of change in the capacitance values ​​of the capacitance elements C1 to C8, and therefore the effect of disturbances can be offset at least partially. Therefore, the output value of the force Fz can be prevented from being affected by disturbances, and the force sensor 10 can have high performance.

[0207] Even if other-axis sensitivity occurs in each axis component, the correction calculation can be performed as described above, so that the other-axis sensitivity can be reduced and the occurrence of other-axis sensitivity can be suppressed to a negligible level.

[0208] 15, it is possible to prevent the output value of the force Fz from being affected by disturbances such as noise or ambient temperature, thereby improving the detection accuracy of the force sensor 10. As a result, it is possible to improve the performance of the force sensor 10.

[0209] (Variation 4) In the above-described embodiment, an example has been described in which the first displacement body 50 is connected to the first tilting portion 35L arranged on the negative side in the X-axis direction with respect to the first connection portion 32, and the second displacement body 60 is connected to the second tilting portion 37R arranged on the positive side in the X-axis direction with respect to the second connection portion 33. However, the embodiment is not limited to this. For example, the first displacement body 50 may be connected to the first tilting portion 35R arranged on the positive side in the X-axis direction with respect to the first connection portion 32, and the second displacement body 60 may be connected to the second tilting portion 37L arranged on the negative side in the X-axis direction with respect to the second connection portion 33. Even in this case, when the force receiving body 20 receives a force Fz in the Z-axis direction, the first displacement portion 54 and the second displacement portion 64 can be displaced to opposite sides to each other in the Z-axis direction.

[0210] (Variation 5) In the above-described embodiment, the first displacement portion 54 and the second displacement portion 64 of the first flexure body 30A are disposed on the negative side in the Y-axis direction with respect to the tilting structure 31, and an example has been described in which both are disposed on one side of the tilting structure 31. However, the embodiment is not limited to this. For example, the first displacement portion 54 may be disposed on one side with respect to the tilting structure 31, and the second displacement portion 64 may be disposed on the other side with respect to the tilting structure 31. More specifically, when the first displacement portion 54 is disposed on the negative side in the Y-axis direction with respect to the tilting structure 31, the second displacement portion 64 may be disposed on the positive side in the Y-axis direction with respect to the tilting structure 31. Alternatively, when the first displacement portion 54 is disposed on the positive side in the Y-axis direction with respect to the tilting structure 31, the second displacement portion 64 may be disposed on the negative side in the Y-axis direction with respect to the tilting structure 31. The same applies to the second flexure body 30B to the fourth flexure body 30D.

[0211] (Second embodiment) Next, a force sensor according to a second embodiment of the present invention will be described with reference to FIGS.

[0212] The second embodiment shown in Figs. 17 to 19 is mainly different in that the force receiving body and the fixed body are connected by two strain bodies. The other configurations are substantially the same as those of the first embodiment shown in Figs. 1 to 16. In Figs. 17 to 19, the same parts as those of the first embodiment shown in Figs. 1 to 16 are denoted by the same reference numerals and detailed description is omitted. Fig. 17 is a plan sectional view showing a force sensor according to the second embodiment. Fig. 18 is a front view showing a schematic deformation state of the first strain body in Fig. 17 when a force in the positive direction of the Z axis is applied, as viewed toward the positive side of the Y axis. Fig. 19 is a front view showing a schematic deformation state of the second strain body in Fig. 17 when a force in the positive direction of the Z axis is applied, as viewed toward the negative side of the Y axis.

[0213] In this embodiment, as shown in FIG. 17, the force receiving body 20 and the fixed body 25 are connected by two flexure bodies 30E and 30F. The two flexure bodies 30E and 30F include a first flexure body 30E and a second flexure body 30F. In the example shown in FIG. 17, when viewed in the Z-axis direction, the first flexure body 30E is disposed on the Y-axis direction positive side with respect to the center O of the force receiving body 20. Similarly, when viewed in the Z-axis direction, the second flexure body 30F is disposed on the Y-axis direction negative side with respect to the center O of the force receiving body 20. The second direction of the first flexure body 30E and the second direction of the second flexure body 30F may both be the X-axis direction. However, this is not limited to this, and the second direction of the first flexure body 30E and the second direction of the second flexure body 30F may be the Y-axis direction. Also, one of the second direction of the first flexure body 30E and the second direction of the second flexure body 30F may be the X-axis direction and the other may be the Y-axis direction. Alternatively, at least one of the second direction of the first flexure body 30E and the second direction of the second flexure body 30F may not be aligned along either the X-axis or the Y-axis. In this embodiment, the first flexure body 30E includes two first displacement parts 54 that are displaced to one side in the Z-axis direction when the force receiving body 20 receives a force Fz in the Z-axis direction. The second flexure body 30F includes two second displacement parts 64 that are displaced to the other side in the Z-axis direction when the force receiving body 20 receives a force Fz in the Z-axis direction. The first flexure body 30E and the second flexure body 30F are similar in configuration to the first flexure body 30A shown in FIG. 4 and the like except for the displacement bodies, and therefore detailed description of the configuration other than the displacement bodies will be omitted.

[0214] As shown in FIG. 18, the first strain body 30E according to the present embodiment includes two first displacement bodies 50L and 50R. One of the first displacement bodies 50L is connected to the first tilting portion 35L arranged on the negative side in the X-axis direction with respect to the first connection portion 32. The other first displacement body 50R is connected to the first tilting portion 35R arranged on the positive side in the X-axis direction with respect to the first connection portion 32. The first displacement body 50L is configured similarly to the first displacement body 50 shown in FIG. 4 and the like, and is arranged in the same direction. The first displacement body 50R is configured similarly to the first displacement body 50 shown in FIG. 4 and the like, but is arranged in the opposite direction to the first displacement body 50.

[0215] More specifically, the first connecting portion 51 of the first displacement body 50L is attached to the first tilting facing surface 35a of the first tilting portion 35L. The first arm portion 53 of the first displacement body 50L extends in a direction from the first tilting portion 35L toward the X-axis direction positive side. The first displacement portion 54 of the first displacement body 50L is connected to the first tilting portion 35L via the first connecting portion 51, the first extension portion 52, and the first arm portion 53, and is disposed on the X-axis direction positive side with respect to the first tilting portion 35L. The first displacement portion 54 of the first displacement body 50L is disposed on the X-axis direction negative side with respect to the first displacement portion 54 of the first displacement body 50R. The first displacement portion 54 of the first displacement body 50L is disposed on the X-axis direction negative side with respect to the central axis CL of the tilting structure 31.

[0216] The first connecting portion 51 of the first displacement body 50R is attached to the first tilting facing surface 35a of the first tilting portion 35R. The first arm portion 53 of the first displacement body 50R extends in a direction from the first tilting portion 35R toward the X-axis direction negative side. The first displacement portion 54 of the first displacement body 50R is connected to the first tilting portion 35R via the first connecting portion 51, the first extension portion 52, and the first arm portion 53, and is disposed on the X-axis direction negative side with respect to the first tilting portion 35R. The first displacement portion 54 of the first displacement body 50R is disposed on the X-axis direction positive side with respect to the first displacement portion 54 of the first displacement body 50L. The first displacement portion 54 of the first displacement body 50R is disposed on the X-axis direction positive side with respect to the central axis CL of the tilting structure 31.

[0217] 17, the first displacement portion 54 of the first displacement body 50L and the first displacement portion 54 of the first displacement body 50R according to this embodiment may each be disposed on the negative side in the Y axis direction with respect to the tilting structure 31. However, the two first displacement portions 54 may each be disposed on the positive side in the Y axis direction with respect to the tilting structure 31.

[0218] As shown in FIG. 19, the second strain body 30F according to the present embodiment includes two second displacement bodies 60L and 60R. One of the second displacement bodies 60L is connected to the second tilting portion 37L arranged on the X-axis direction positive side with respect to the second connection portion 33. The other second displacement body 60R is connected to the second tilting portion 37R arranged on the X-axis direction negative side with respect to the second connection portion 33. The second displacement body 60L is configured similarly to the second displacement body 60 shown in FIG. 4 and the like, but is arranged in the opposite direction to the second displacement body 60. The second displacement body 60R is configured similarly to the second displacement body 60 shown in FIG. 4 and the like, and is arranged in the same direction.

[0219] More specifically, the second connecting portion 61 of the second displacement body 60L is attached to the second tilting facing surface 37a of the second tilting portion 37L. The second arm portion 63 of the second displacement body 60L extends in a direction from the second tilting portion 37L toward the X-axis direction negative side. The second displacement portion 64 of the second displacement body 60L is connected to the second tilting portion 37L via the second connecting portion 61, the second extension portion 62, and the second arm portion 63, and is disposed on the X-axis direction negative side with respect to the second tilting portion 37L. The second displacement portion 64 of the second displacement body 60L is disposed on the X-axis direction positive side with respect to the second displacement portion 64 of the second displacement body 60R. The second displacement portion 64 of the second displacement body 60L is disposed on the X-axis direction positive side with respect to the central axis CL of the tilting structure 31.

[0220] The second connecting portion 61 of the second displacement body 60R is attached to the second tilting facing surface 37a of the second tilting portion 37R. The second arm portion 63 of the second displacement body 60R extends in a direction from the second tilting portion 37R toward the X-axis direction positive side. The second displacement portion 64 of the second displacement body 60R is connected to the second tilting portion 37R via the second connecting portion 61, the second extension portion 62, and the second arm portion 63, and is disposed on the X-axis direction positive side with respect to the second tilting portion 37R. The second displacement portion 64 of the second displacement body 60R is disposed on the X-axis direction negative side with respect to the second displacement portion 64 of the second displacement body 60L. The second displacement portion 64 of the second displacement body 60R is disposed on the X-axis direction negative side with respect to the central axis CL of the tilting structure 31.

[0221] 17, the second displacement portion 64 of the second displacement body 60L and the second displacement portion 64 of the second displacement body 60R according to this embodiment may each be disposed on the positive side in the Y axis direction with respect to the tilting structure 31. However, the two second displacement portions 64 may each be disposed on the negative side in the Y axis direction with respect to the tilting structure 31.

[0222] As shown in FIGS. 17 to 19, a detection element 70 according to the present embodiment includes two first capacitance elements C1L, C1R and two second capacitance elements C2L, C2R.

[0223] The first capacitance elements C1L and C1R are capacitance elements for the first strain generating body 30E. The first capacitance element C1L detects a change in capacitance value due to the displacement of the first displacement portion 54 of the first displacement body 50L in the Z-axis direction. The first capacitance element C1R detects a change in capacitance value due to the displacement of the first displacement portion 54 of the first displacement body 50R in the Z-axis direction. The first capacitance element C1L and the first capacitance element C1R may each include a first displacement electrode substrate Ed1 and a first fixed electrode substrate Ef1 shown in FIG. 4 and the like. The first fixed electrode substrate Ef1 of the first capacitance element C1L may be supported by the fixed body 25 via the first pedestal 26 shown in FIG. 4 and the like. The first fixed electrode substrate Ef1 of the first capacitance element C1R may be supported by the fixed body 25 via the second pedestal 27 shown in FIG. 4 and the like. The first displacement electrode substrate Ed1 of the first capacitance element C1L may be provided on the first displacement portion 54 of the first displacement body 50L. The displacement electrode substrate Ed1 of the first capacitance element C1R may be provided on the first displacement portion 54 of the first displacement body 50R.

[0224] The second capacitance elements C2L and C2R are capacitance elements for the second strain generating body 30F. The second capacitance element C2L detects a change in capacitance value due to the displacement of the second displacement portion 64 of the second displacement body 60L in the Z-axis direction. The second capacitance element C2R detects a change in capacitance value due to the displacement of the second displacement portion 64 of the second displacement body 60R in the Z-axis direction. Both the second capacitance element C2L and the second capacitance element C2R may include a second displacement electrode substrate Ed2 and a second fixed electrode substrate Ef2 shown in FIG. 4 and the like. The second fixed electrode substrate Ef2 of the second capacitance element C2L may be supported by the fixed body 25 via the first pedestal 26 shown in FIG. 4 and the like. The second fixed electrode substrate Ef2 of the second capacitance element C2R may be supported by the fixed body 25 via the second pedestal 27 shown in FIG. 4 and the like. The second displacement electrode substrate Ed2 of the second capacitance element C2L may be provided on the second displacement portion 64 of the second displacement body 60L. The displacement electrode substrate Ed2 of the second capacitance element C2R may be provided on the second displacement portion 64 of the second displacement body 60R.

[0225] When a force Fx acts on the first flexure body 30E shown in FIG. 18 in the X-axis direction positive side, the tilting structure 31 elastically deforms in the same manner as the first flexure body 30A shown in FIG. 8. As a result, the first displacement body 50L rotates in the same direction as the first displacement body 50 shown in FIG. 8, and the first displacement portion 54 of the first displacement body 50L is displaced in the Z-axis direction negative side. This increases the capacitance value of the first capacitance element C1L. The first displacement body 50R rotates in the same direction as the second displacement body 60 shown in FIG. 8, and the first displacement portion 54 of the first displacement body 50R is displaced in the Z-axis direction positive side. This reduces the capacitance value of the first capacitance element C1R.

[0226] When a force Fx acts on the second flexure body 30F shown in Fig. 19 in the positive direction in the X-axis direction, the tilting structure 31 elastically deforms in the opposite direction to the first flexure body 30A shown in Fig. 8. That is, the capacitance value of the second capacitance element C2L decreases and the capacitance value of the second capacitance element C2R increases.

[0227] When a force Fy acts on the first flexure body 30E shown in Fig. 18 in the Y-axis direction positive direction, it is elastically deformed in the same manner as the first flexure body 30A shown in Fig. 9. Therefore, the capacitance value of the first capacitance element C1L decreases, and the capacitance value of the first capacitance element C1R decreases. However, the amount of decrease in the capacitance value of the first capacitance element C1L and the capacitance value of the first capacitance element C1R are negligibly small.

[0228] When a force Fy acts on the second flexure body 30F shown in Fig. 19 in the Y-axis direction positive direction, it is elastically deformed in the opposite direction to the first flexure body 30A shown in Fig. 9. Therefore, the capacitance value of the second capacitance element C2L increases, and the capacitance value of the second capacitance element C2R increases. However, the amount of decrease in the capacitance value of the second capacitance element C2L and the amount of decrease in the capacitance value of the second capacitance element C2R are negligibly small.

[0229] When a force Fz acts on the first flexure body 30E shown in FIG. 18 in the Z-axis direction positive side, the first flexure body 30E is elastically deformed in the same manner as the first flexure body 30A shown in FIG. 10A. As a result, the first displacement body 50L rotates in the same direction as the first displacement body 50 shown in FIG. 10A, and the first displacement portion 54 of the first displacement body 50L is displaced in the Z-axis direction positive side. This causes the capacitance value of the first capacitance element C1L to decrease. The first displacement body 50R rotates in the opposite direction to the second displacement body 60 shown in FIG. 10A, and the first displacement portion 54 of the first displacement body 50R is displaced in the Z-axis direction positive side. This causes the capacitance value of the first capacitance element C1R to decrease.

[0230] When a force Fz acts on the second flexure body 30F shown in FIG. 19 in the Z-axis direction positive direction, the second flexure body 30F is elastically deformed in the same manner as the first flexure body 30A shown in FIG. 10A. As a result, the second displacement body 60L rotates in the opposite direction to the first displacement body 50 shown in FIG. 10A, and the second displacement portion 64 of the second displacement body 60L is displaced to the Z-axis direction negative side. This increases the capacitance value of the second capacitance element C2L. The second displacement body 60R rotates in the same direction as the second displacement body 60 shown in FIG. 10A, and the second displacement portion 64 of the second displacement body 60R is displaced to the Z-axis direction negative side. This increases the capacitance value of the second capacitance element C2R.

[0231] Thus, according to the present embodiment, the first strain body 30E includes a first displacement portion 54 that displaces to one side in the Z-axis direction when the force receiving body 20 receives a force Fz in the Z-axis direction. The second strain body 30F includes a second displacement portion 64 that displaces to the other side in the Z-axis direction when the force receiving body 20 receives a force Fz in the Z-axis direction. This makes it possible to increase one of the capacitance values ​​of the first capacitance elements C1L, C1R and the second capacitance elements C2L, C2R, and to decrease the other. In this case, an output value indicating the magnitude of the force Fz in the Z-axis direction can be calculated based on the difference between the amount of change in the capacitance value of the first capacitance elements C1L, C1R and the amount of change in the capacitance value of the second capacitance elements C2L, C2R. This makes it possible to prevent the output value of the force Fz from being affected by disturbances such as noise or ambient temperature, and to improve the detection accuracy of the force sensor 10. As a result, the force sensor 10 can have high performance.

[0232] According to this embodiment, the first tilting parts 35L and 35R of the tilting structure 31 of the first flexure body 30E are connected to the force receiving body 20 via the first connection part 32, and the second tilting parts 37L and 37R of the second flexure body 30F are connected to the fixed body 25 via the second connection part 33. The first displacement part 54 of the first flexure body 30E is connected to the first tilting parts 35L and 35R connected to the first connection part 32. The second displacement part 64 of the second flexure body 30F is connected to the second tilting parts 37L and 37R connected to the second connection part 33. As a result, when a force Fz in the Z-axis direction is applied, the first displacement bodies 50L and 50R of the first flexure body 30E can be tilted, and the second displacement bodies 60L and 60R of the second flexure body 30F can be tilted. In this case, one of the first displacement portion 54 of the first displacement body 50L, 50R and the second displacement portion 64 of the second displacement body 60L, 60R can be displaced to the positive side in the Z-axis direction, and the other can be displaced to the negative side in the Z-axis direction. Therefore, one of the capacitance value of the first capacitance elements C1L, C1R and the capacitance value of the second capacitance elements C2L, C2R can be increased, and the other can be decreased. As a result, an output value indicating the magnitude of the force Fz can be calculated based on the difference between the amount of change in the capacitance value of the first capacitance elements C1L, C1R and the amount of change in the capacitance value of the second capacitance elements C2L, C2R.

[0233] According to the present embodiment, the first flexure body 30E includes two first displacement parts 54, and the second flexure body 30F includes two second displacement parts 64. The displacements of the two first displacement parts 54 are detected by the corresponding capacitance elements C1L and C1R, respectively, and the displacements of the two second displacement parts 64 are detected by the corresponding capacitance elements C2L and C2R, respectively. This allows the force Fz to be detected by the four capacitance elements C1L, C1R, C2L, and C2R, and the detection sensitivity and detection accuracy can be improved. This improves the reliability of the force sensor 10.

[0234] According to the present embodiment, the first flexure body 30E includes two first displacement parts 54, and the first displacement part 54 of the first displacement body 50L is connected to one of the first tilting parts 35L of the first flexure body 30E, and the first displacement part 54 of the first displacement body 50R is connected to the other first tilting part 35R of the first flexure body 30E. As a result, when a force Fz in the Z-axis direction acts on the two first displacement parts 54, they can be displaced to the same side in the Z-axis direction. When a force Fx in the X-axis direction acts on the two first displacement parts 54, they can be displaced to opposite sides in the Z-axis direction. In this case, one of the first capacitance element C1L and the first capacitance element C1R can be increased, and the other can be decreased. Therefore, an output value indicating the magnitude of the force Fx in the X-axis direction can be calculated based on the difference between the amount of change in the capacitance value of the first capacitance element C1L and the amount of change in the capacitance value of the first capacitance element C1R. This makes it possible to prevent the output value of the force Fx from being affected by disturbances such as noise or ambient temperature, thereby improving the detection accuracy of the force sensor 10. As a result, the performance of the force sensor 10 can be improved.

[0235] Further, according to the present embodiment, the second flexure body 30F includes two second displacement parts 64, and the second displacement part 64 of the second displacement body 60L is connected to one of the second tilting parts 37L of the second flexure body 30F, and the second displacement part 64 of the second displacement body 60R is connected to the other second tilting part 37R of the second flexure body 30F. As a result, when a force Fz in the Z-axis direction acts on the two second displacement parts 64, they can be displaced to the same side in the Z-axis direction. When a force Fx in the X-axis direction acts on the two second displacement parts 64, they can be displaced to opposite sides in the Z-axis direction. In this case, one of the second capacitance element C2L and the second capacitance element C2R can be increased, and the other can be decreased. Therefore, an output value indicating the magnitude of the force Fx in the X-axis direction can be calculated by the difference between the amount of change in the capacitance value of the second capacitance element C2L and the amount of change in the capacitance value of the second capacitance element C2R. This makes it possible to prevent the output value of the force Fx from being affected by disturbances such as noise or ambient temperature, thereby improving the detection accuracy of the force sensor 10. As a result, the performance of the force sensor 10 can be improved.

[0236] Furthermore, according to this embodiment, first flexure body 30E is disposed on the positive side in the Y axis direction with respect to center O of force receiving body 20, and second flexure body 30F is disposed on the negative side in the Y axis direction with respect to center O of force receiving body 20. This allows them to be disposed on both sides in the Y axis direction with respect to center O of force receiving body 20 when viewed in the Z axis direction. This makes it possible to improve the detection accuracy of force or moment.

[0237] (Variation 6) In the above-described embodiment, the first flexure body 30E includes two first displacement bodies 50L and 50R. However, the embodiment is not limited to this. For example, the number of displacement bodies included in the first flexure body 30E may be one. More specifically, the first flexure body 30E may include one of the first displacement body 50L and the first displacement body 50R, and not include the other. Even in this case, the output value indicating the magnitude of the force Fz in the Z-axis direction can be calculated based on the difference between the change in the capacitance value of the first capacitance element and the change in the capacitance value of the second capacitance element. Similarly, the number of second displacement parts 64 included in the second flexure body 30F may be one.

[0238] (Variation 7) In the above-described embodiment, an example in which the force receiving body 20 and the fixed body 25 are connected by two flexure bodies 30E and 30F has been described. However, the embodiment is not limited to this. For example, the force receiving body 20 and the fixed body 25 may be connected by four flexure bodies. For example, the force receiving body 20 and the fixed body 25 may be connected by two first flexure bodies 30E and two second flexure bodies 30F. In this case, the two first flexure bodies 30E and the two second flexure bodies 30F may be arranged in an annular shape in the same manner as the force sensor 10 shown in FIG. 3. This makes it possible to detect six-axis components of force.

[0239] The present invention is not limited to the above-mentioned embodiment and modified examples, and the components can be modified and embodied in the implementation stage without departing from the gist of the invention. In addition, various inventions can be formed by appropriate combinations of multiple components disclosed in the above-mentioned embodiment and modified examples. Some components may be deleted from all the components shown in the embodiment and modified examples. Furthermore, components from different embodiments and modified examples may be appropriately combined.

Claims

1. a first sensor body that receives the force or moment to be detected; a second sensor body disposed at a position different from the first sensor body in a first direction; a strain generating body that connects the first sensor body and the second sensor body and is elastically deformed by the action of a force or moment applied to the first sensor body; A detection element for detecting a displacement caused by elastic deformation of the strain body; a detection circuit that outputs an electrical signal indicative of a force or moment acting on the first sensor body based on a detection result of the detection element; Equipped with the strain generating body includes a first displacement portion and a second displacement portion which are displaced in opposite directions in the first direction when the first sensor body receives a force in the first direction, the detection element includes a first capacitive element that detects a change in capacitance value due to displacement of one of the first displacement portion and the second displacement portion in the first direction, and a second capacitive element that detects a change in capacitance value due to displacement of the other of the first displacement portion and the second displacement portion in the first direction, the strain body includes a tilting structure disposed between the first sensor body and the second sensor body, a first connection portion connecting the first sensor body and the tilting structure, and a second connection portion connecting the second sensor body and the tilting structure, the tilting structure includes a pair of first tilting parts connected to the first connection part and arranged on both sides of the first connection part in a second direction perpendicular to the first direction, and a pair of second tilting parts connected to the second connection part and arranged on both sides of the second connection part in the second direction, the first displacement portion is connected to the first tilting portion that is arranged on one side in the second direction with respect to the first connection portion, The second displacement portion is connected to the second tilting portion that is arranged on the other side in the second direction with respect to the second connection portion. Force sensor.

2. The first displacement portion is disposed on a side of the other first tilt portion with respect to the corresponding first tilt portion, The second displacement portion is disposed on a side of the other second tilt portion with respect to the corresponding second tilt portion. The force sensor according to claim 1 .

3. The first displacement portion is connected to the first tilt portion via a first arm portion, the first arm portion extends in a direction from the corresponding first tilting portion toward the other first tilting portion in the second direction, The second displacement portion is connected to the second tilt portion via a second arm portion, The second arm portion extends in a direction from the corresponding second tilting portion toward the other second tilting portion in the second direction. The force sensor according to claim 2 .

4. the first arm portion is attached to a surface of the corresponding first tilting portion facing the first sensor body via a first connecting portion; The second arm portion is attached to a surface of the corresponding second tilting portion facing the second sensor body via a second connecting portion. The force sensor according to claim 3 .

5. The first displacement portion and the second displacement portion are disposed on one side of the tilting structure in a third direction perpendicular to the first direction and the second direction. The force sensor according to claim 1 .

6. The tilting structure further includes a pair of first deformation portions connecting the corresponding first tilting portions to the first connection portion, and a pair of second deformation portions connecting the corresponding second tilting portions to the second connection portion, a dimension of the first deformation portion in the first direction is smaller than a dimension of the first tilt portion in the first direction; A dimension of the second deformation portion in the first direction is smaller than a dimension of the second tilting portion in the first direction. The force sensor according to claim 1 .

7. the first deformation portion includes a first opposing surface that faces the first sensor body, the first opposing surface is disposed on a side of the second sensor body relative to a surface of the first tilting portion that faces the first sensor body, the second deformation portion includes a second opposing surface facing the second sensor body, the second opposing surface is disposed on a side of the first sensor body relative to a surface of the second tilting portion that faces the second sensor body; The force sensor according to claim 6.

8. The first opposing surface and the second opposing surface are each formed in a curved shape. The force sensor according to claim 7.

9. the tilting structure further includes a pair of third deformation portions connecting the first tilting portion and the corresponding second tilting portion, a dimension of the third deformation portion in the second direction is smaller than a dimension of the first tilting portion in the second direction and smaller than a dimension of the second tilting portion in the second direction; The force sensor according to claim 8.

10. The third deformation portion includes a curved third opposing surface opposing the other third deformation portion. The force sensor according to claim 9.

11. the first capacitance element includes a first displacement electrode substrate provided on one of the first displacement portion and the second displacement portion, and a first fixed electrode substrate facing the first displacement electrode substrate, the second capacitance element includes a second displacement electrode substrate provided on the other of the first displacement portion and the second displacement portion, and a second fixed electrode substrate facing the second displacement electrode substrate; The force sensor according to claim 1 .

12. the first fixed electrode substrate and the second fixed electrode substrate are supported by the second sensor body; The force sensor according to claim 11.

13. the first fixed electrode substrate and the second fixed electrode substrate are each supported by the second sensor body via a base; The force sensor according to claim 11.

14. The first sensor body and the second sensor body are connected by four of the strain bodies, The four flexure bodies include a first flexure body, a second flexure body, a third flexure body, and a fourth flexure body, The first direction is a Z-axis direction in an XYZ three-dimensional coordinate system, the first flexure body is disposed on the positive side of the Y axis direction with respect to the center of the first sensor body, the second flexure body is disposed on the negative side of the X axis direction with respect to the center of the first sensor body, the third flexure body is disposed on the negative side of the Y axis direction with respect to the center of the first sensor body, and the fourth flexure body is disposed on the positive side of the X axis direction with respect to the center of the first sensor body. The force sensor according to claim 1 .

15. the first displacement portion and the second displacement portion are disposed on a center side of the first sensor body with respect to the corresponding tilt structure; The force sensor according to claim 14.

16. a first sensor body that receives the force or moment to be detected; a second sensor body disposed at a position different from the first sensor body in a first direction; two strain bodies that connect the first sensor body and the second sensor body and are elastically deformed by the action of a force or moment applied to the first sensor body; A detection element for detecting a displacement caused by the elastic deformation of each of the strain bodies; a detection circuit that outputs an electrical signal indicative of a force or moment acting on the first sensor body based on a detection result of the detection element; Equipped with The two flexure bodies include a first flexure body and a second flexure body, the first strain body includes a first displacement portion that is displaced to one side in the first direction when the first sensor body receives a force in the first direction, the second strain generating body includes a second displacement portion that is displaced to the other side in the first direction when the first sensor body receives a force in the first direction, the detection element includes a first capacitive element that detects a change in capacitance value due to displacement of the first displacement section in the first direction, and a second capacitive element that detects a change in capacitance value due to displacement of the second displacement section in the first direction, each of the first and second strain bodies includes a tilting structure disposed between the first and second sensor bodies, a first connection portion connecting the first sensor body and the tilting structure, and a second connection portion connecting the second sensor body and the tilting structure; the tilting structure includes a pair of first tilting parts connected to the first connection part and arranged on both sides of the first connection part in a second direction perpendicular to the first direction, and a pair of second tilting parts connected to the second connection part and arranged on both sides of the second connection part in the second direction, The first displacement portion is connected to the first tilt portion of the first strain body, The second displacement portion is connected to the second tilting portion of the second strain body. Force sensor.

17. The first strain body includes two of the first displacement portions, one of the first displacement portions is connected to one of the first tilting portions of the first flexure body, and the other of the first displacement portions is connected to the other of the first tilting portions of the first flexure body, The second strain body includes two of the second displacement portions, One of the first displacement portions is connected to one of the second tilt portions of the second flexure body, and the other of the second displacement portions is connected to the other of the second tilt portions of the second flexure body. The force sensor according to claim 16.

18. The first direction is a Z-axis direction in an XYZ three-dimensional coordinate system, The first strain generating body is disposed on the positive side of the Y axis direction with respect to the center of the first sensor body, and the second strain generating body is disposed on the negative side of the Y axis direction with respect to the center of the first sensor body. The force sensor according to claim 16.

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