JP6265430B2 - Multi-axis sensor and method of manufacturing multi-axis sensor - Google Patents

Description

  The present invention relates to a multi-axis sensor and a method for manufacturing the multi-axis sensor.

  Conventionally, as a multi-axis sensor, for example, the one described in FIG. The multi-axis sensor includes a first strain body and a second strain body that are arranged to face each other. The 1st strain body has the 1st bulk part, the 1st diaphragm part formed thinner than the 1st bulk part, and the 1st support | pillar part formed in the 1st diaphragm part. Similarly, the second strain body includes a second bulk portion, a second diaphragm portion formed thinner than the second bulk portion, and a second support column portion formed on the second diaphragm portion. ing. The first strut portion of the first strain body and the second strut portion of the second strain body are connected by bolts.

  In this multi-axis sensor, a plurality of strain gauges are arranged on a surface opposite to the surface on which the first support portion of the first strain body is formed, and the second strain body is formed by the plurality of strain gauges. The force applied to can be measured.

JP 2005-31062 A

  However, in the conventional multi-axis sensor, the first strain body and the second strain body are manufactured separately, and then the first strut portion of the first strain body and the second strut portion of the second strain body. Are connected by bolts, and there is a problem that the manufacturing cost increases.

  Moreover, when the 1st support | pillar part and the 2nd support | pillar part are connected with the volt | bolt, there exists a possibility that the distortion applied by the force added to the 2nd strain body and the said force may not be correctly transmitted to a strain gauge. For this reason, the conventional multi-axis sensor has a problem that a force detection error occurs, or the hysteresis of the output of the strain gauge increases, resulting in a decrease in force detection accuracy.

  Although it is conceivable to connect the first strut body and the second strut body by welding instead of bolts, in the case of welding, the first strain body and the second strain body are parallel due to thermal contraction during welding. There is a risk of being connected while being tilted. On the other hand, when the first strain body and the second strain body are tightly fixed during welding in order to keep the first strain body and the second strain body in parallel, the first diaphragm section and the second diaphragm section Permanent distortion may be applied, and the yield may be reduced. In addition, even if the above problems are solved and connected by welding, the crystal structure and material of the welded part and the non-welded part are slightly different, so the force applied to the second strain body is accurately transmitted to the strain gauge. The problem remains difficult.

  Furthermore, since the conventional multi-axis sensor has a structure in which the first diaphragm portion is surrounded by the first bulk portion, the first strain generation having the first diaphragm portion by cutting using a cutting tool such as an end mill. It is practically impossible to form the body and the second strain body integrally.

  This invention is made | formed in view of the said situation, The place made into the subject is providing the manufacturing method of a low-cost and high-performance multi-axis sensor and a multi-axis sensor.

  In order to solve the above problem, a multi-axis sensor according to the present invention includes a first bulk portion and a first diaphragm portion formed thinner than the first bulk portion, and a rear end surface provided with a detection element. Including a first strain body, a second bulk portion, and a second diaphragm portion that is opposed to the first diaphragm portion and is thinner than the second bulk portion, and includes a front end face that is attached to a measurement target. And a column body connecting the first diaphragm portion and the second diaphragm portion, the first diaphragm portion constituting a part of the rear end surface of the first strain body, and It reaches the outer peripheral edge of the rear end face of the first strain body, and the first strain body and the second strain body are arranged apart from each other, and the first strain body, the second strain body, and the support column The body is integrally formed by cutting a single member To.

  In this configuration, since the first diaphragm portion constitutes a part of the rear end surface of the first strain body and reaches the outer peripheral edge of the rear end surface of the first strain body, the outer peripheral surface of the first strain body The first diaphragm portion can be formed by cutting from the above. Therefore, according to this configuration, it is possible to provide a low-cost multi-axis sensor in which the first strain body, the second strain body, and the support body are integrally formed by cutting.

  Furthermore, in this configuration, since the first strain body, the second strain body, and the support body are integrally formed, the force applied to the second strain body and the strain generated by the force are efficient. It is transmitted accurately and accurately to the detection element of the first strain body. Therefore, according to this configuration, it is possible to provide a high-performance multi-axis sensor with good linearity and low hysteresis.

  The multi-axis sensor further includes a cover body that covers the rear end surface, and the cover body is preferably attached to a flange portion formed on the outer peripheral surface of the first bulk portion and spaced from the first diaphragm portion.

  According to this configuration, since the cover body is separated from the first diaphragm portion, the force applied to the second strain body and the strain generated by the force are the rear end surface (detection element) of the first strain body. It is possible to protect the detection element without hindering transmission to the sensor.

  In the multi-axis sensor, the second diaphragm portion can be configured such that the rear end surface is located in front of the rear end surface of the second bulk portion.

  In this configuration, the column body can be made longer than the multi-axis sensor in which the rear end surface of the second diaphragm portion is located on the same plane as the rear end surface of the second bulk portion. Therefore, according to this configuration, it is possible to improve the detection sensitivity of the force and distortion generated by the force.

  In the multi-axis sensor, when the support body is cut at the front end surface of the first bulk portion, the cross-sectional area of the support body can be configured to be larger than the area of the front end surface of the first bulk portion.

  According to this configuration, the strength (rigidity) of the entire sensor can be increased. For example, when the support body is thickened and the cross-sectional area is increased without increasing the number of support bodies, the detection sensitivity is lowered, but in addition to the increase in the strength of the entire sensor, the cutting process can be simplified. On the other hand, when the cross-sectional area is increased by increasing the number of support columns, although the machining is complicated, the strength of the entire sensor can be increased without reducing the detection sensitivity.

  In the multi-axis sensor, the column body has four side surfaces, and two of the four side surfaces facing the circumferential direction of the first strain body are both flat surfaces. The two side surfaces facing each other in the radial direction may be curved at least on the inner side surface.

  According to this structure, the intensity | strength of the whole sensor can be increased depending on the setting of the width | variety of a support | pillar body.

  In the multi-axis sensor, a through hole extending in the front-rear direction may be formed at the center of the first strain body and the second strain body.

  According to this configuration, it is possible to realize space saving such as reducing the shape of the robot arm, for example, by passing cables from other sensors and devices using the through holes.

  In the multi-axis sensor, it is preferable that a rear end surface of the first strain body is formed flat and a plurality of detection elements are provided on the same plane. According to this structure, arrangement | positioning of a detection element becomes easy and it can improve manufacturing efficiency.

  In the multi-axis sensor, a sensor element whose resistance value changes when strain is generated on the rear end face of the first strain body can be used as the detection element. As the detecting element whose resistance value changes, a strain gauge, a piezoresistive element, a pressure-sensitive resistance ink, or the like can be used. Further, as the detection element, an element whose capacitance value changes when the rear end face of the first strain body is displaced may be used.

  In order to solve the above problems, a multi-axis sensor manufacturing method according to the present invention includes a first strain body having a first diaphragm portion on the rear end face side, and a first strain body in front of the first strain body. A multi-axis sensor comprising: a second strain generating body that is spaced apart from the first diaphragm portion and has a second diaphragm portion; and a post body that extends in the front-rear direction connecting the first diaphragm portion and the second diaphragm portion. A manufacturing method, wherein cutting is performed from an outer peripheral surface or a front end surface side of a columnar bulk member extending in the front-rear direction by a cutting means, a notch is formed on the front end surface side of the bulk member, and the bulk is formed by the cutting means. The first step of forming the first diaphragm portion and the second diaphragm portion by cutting from the outer peripheral surface side of the member and forming the first groove portion extending in the front-rear direction behind the notch portion, and the cutting means From the outer peripheral side of the bulk member Cutting machining, by forming a second groove which is connected to the first groove, characterized in that it comprises a second step of forming a first strain generating body and the second strain generating body spaced from each other.

  According to this configuration, since the multi-axis sensor in which the first strain body, the second strain body, and the support body are integrally formed by cutting can be manufactured, the first strain body and the second strain body are manufactured. Manufacturing cost can be reduced compared with the conventional manufacturing method which connects a 1st strain body and a 2nd strain body by connection means, such as a bolt, after manufacturing a body separately. Furthermore, according to this configuration, it is possible to manufacture a high-performance multi-axis sensor with better linearity and less hysteresis compared to the conventional manufacturing method.

  In the multi-axis sensor manufacturing method, the first step is to form a communication hole communicating with the notch portion and the first groove portion by cutting from the front end surface side of the bulk member by the cutting means, or the notch portion. Before forming the first groove portion, the column member having at least four side surfaces is formed by cutting from the front end surface or the rear end surface side of the bulk member by cutting means to form a through hole extending in the front-rear direction. A step of forming may be included.

  According to the present invention, a low-cost and high-performance multi-axis sensor and a method for manufacturing the multi-axis sensor can be provided.

It is the perspective view which showed typically the multi-axis sensor which concerns on 1st Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a hexahedral view of a multi-axis sensor according to a first embodiment of the present invention, where (a) is a front view, (b) is a left side view, (c) is a plan view (top view), and (d). Is a right side view, (e) is a rear view, and (f) is a bottom view. It is a multi-axis sensor which concerns on 1st Embodiment of this invention, Comprising: (a) is a top view which shows a 2nd diaphragm part, (b) is a bottom view which shows a 1st diaphragm part. It is a multi-axis sensor which concerns on 1st Embodiment of this invention, Comprising: (a) is sectional drawing in the AA 'line of FIG.2 (e), (b) is the BB' line | wire of FIG.2 (f). (C) is sectional drawing in CC 'line of FIG.2 (f). (A) is a figure which shows the relationship between a 1st diaphragm part and a detection element (strain gauge), (b) is a figure which shows the circuit structure of a strain gauge. It is sectional drawing in the AA 'line and BB' line of Fig.5 (a), (a) is when the force Fx parallel to a X-axis direction is applied, (b) is a Z-axis direction. When a parallel force Fz is applied, (c) is when a moment Mx around the X axis is applied, (d) is when a moment My around the Y axis is applied, and (e) a moment around the Z axis. It is a figure when Mz is added. It is a six-view figure of the multi-axis sensor which concerns on 2nd Embodiment of this invention, Comprising: (a) is a front view, (b) is a left view, (c) is a top view (top view), (d) Is a right side view, (e) is a rear view, and (f) is a bottom view. It is a six-view figure of the multi-axis sensor which concerns on 3rd Embodiment of this invention, Comprising: (a) is a front view, (b) is a left view, (c) is a top view (top view), (d) Is a right side view, (e) is a rear view, and (f) is a bottom view. FIG. 10 is a multi-axis sensor according to a third embodiment of the present invention, and is a cross-sectional view taken along line A-A ′ of FIG. It is a six-view figure of the multi-axis sensor which concerns on 4th Embodiment of this invention, Comprising: (a) is a front view, (b) is a left view, (c) is a top view (top view), (d) Is a right side view, (e) is a rear view, and (f) is a bottom view. It is a six-view figure of the multi-axis sensor which concerns on 5th Embodiment of this invention, Comprising: (a) is a front view, (b) is a left view, (c) is a top view (top view), (d) Is a right side view, (e) is a rear view, and (f) is a bottom view. It is a six-view figure of the multi-axis sensor which concerns on 6th Embodiment of this invention, Comprising: (a) is a front view, (b) is a left view, (c) is a top view (top view), (d) Is a right side view, (e) is a rear view, and (f) is a bottom view. It is a multi-axis sensor which concerns on 6th Embodiment of this invention, Comprising: (a) is sectional drawing in the AA 'line of FIG.12 (e), (b) is the BB' line of FIG.12 (f). (C) is sectional drawing in CC 'line of FIG.12 (f). It is a schematic diagram of the multi-axis sensor which concerns on 7th Embodiment of this invention. It is a figure which shows the relationship between a 1st diaphragm part and a detection element (displacement electrode). It is a figure which shows the capacitor | condenser comprised by a displacement electrode and a fixed electrode. It is a multi-axis sensor which concerns on 7th Embodiment of this invention, Comprising: When (a) applied force Fx parallel to the X-axis direction, (b) applied force Fz parallel to the Z-axis direction. It is a figure of time. FIG. 9A is a multi-axis sensor according to a seventh embodiment of the present invention, and FIG. 10A is a diagram when a moment My around a Y axis is applied, and FIG. 9B is a diagram when a moment Mz around a Z axis is applied. .

  Embodiments of a multi-axis sensor and a method for manufacturing the multi-axis sensor according to the present invention will be described below with reference to the accompanying drawings. In the present invention, the direction from the bottom surface of the multi-axis sensor toward the top surface is defined as the front direction, and the direction from the top surface toward the bottom surface is defined as the rear direction.

[First Embodiment]
(Construction)
1 to 4 show a multi-axis sensor 1A according to a first embodiment of the present invention.

  As shown in FIGS. 2C and 2F, the multi-axis sensor 1A has a circular shape in plan view and bottom view. As shown in FIG. 1, the multiaxial sensor 1 </ b> A has a first strain body 10 formed on the bottom surface side, and is spaced apart from the first strain body 10 on the top surface side and parallel to the first strain body 10. A second strain body 20 formed so as to be, and a plurality of (three in the present embodiment) strut bodies 30 formed between the first strain body 10 and the second strain body 20; It has. As will be described in detail later, the first strain body 10, the second strain body 20, and the three support bodies 30 are a single member made of a flexible metal using a cutting tool such as an end mill. Is formed integrally by cutting.

  As shown in FIG. 2, the first strain body 10 includes a first bulk part 11, a first diaphragm part 12, and a flange part 13. An end surface (rear end surface) on the bottom surface side of the first strain body 10 is a flat surface and serves as a detection surface on which a detection element such as a strain gauge is provided. As shown in FIG. 3B, the rear end surface of the first strain body 10 is constituted by a rear end surface of the first diaphragm portion 12 and a rear end surface of the first bulk portion 11.

  The second strain body 20 includes a second bulk portion 21 and a second diaphragm portion 22. An end surface (front end surface) on the top surface side of the second strain body 20 is an attachment surface (power receiving surface) attached to a load that is a measurement target. The front end face of the second strain body 20 is constituted by the front end face of the second bulk portion 21 as shown in FIG.

  As shown in FIGS. 3A and 3B, the three support columns 30 are arranged at an equal distance and an equal angle from the central axis of the multiaxial sensor 1A extending in the front-rear direction. As shown in FIG. 4 (c), the three support columns 30 are located between the rear end surface (detection surface) of the first strain body 10 and the front end surface of the second diaphragm portion 22 of the second strain body 20. In FIG. The three struts 30 each include a side surface that forms the outer peripheral surface of the multiaxial sensor 1A together with the outer peripheral surface of the first strain body 10 and the outer peripheral surface of the second strain body 20, and the circumferential direction of the multiaxial sensor 1A. And two side surfaces adjacent to each other. The three struts 30 have a triangular cross section between the rear end surface of the first strain body 10 and the front end surface of the first strain body 10 (see FIG. 3B). Between the front end surface of the distortion body 10 and the front end surface of the 2nd diaphragm part 22, it has the fan-shaped cross section containing the said triangle shape (refer Fig.3 (a)).

  The first diaphragm portion 12 is formed thinner than the first bulk portion 11. More specifically, the first diaphragm portion 12 has a rear end surface located on the same plane as the rear end surface of the first bulk portion 11 and the rear end surface of the support body 30, and the front end surface is the front end of the first bulk portion 11. It is formed so as to be located behind the surface. Moreover, the 1st diaphragm part 12 exhibits V shape in planar cross section view, as shown in FIG.3 (b). More specifically, the first diaphragm portion 12 is formed on the outer peripheral surface of the first strain body 10 (the rear side of the first strain body 10) along two side surfaces adjacent to each other in the circumferential direction among the side surfaces of the support body 30. It is formed so as to reach the outer peripheral edge of the end face.

  The first bulk portion 11 occupies most of the first strain body 10. The first bulk portion 11 is formed thick from the rear end surface (detection surface) to the front end surface of the first strain body 10. Further, as shown in FIG. 3B and FIG. 4A, the first bulk portion 11 includes three first diaphragm portions 12 and three support bodies 30 from a circular shape in plan view and bottom view. The shape is cut out.

  The flange portion 13 is formed at the front end of the outer peripheral surface of the first bulk portion 11. The circle connecting the outer peripheral surface of the flange portion 13 has the same diameter as the circle connecting the outer peripheral surface of the second strain body 20 (see FIG. 3). A cover body (not shown) that covers the detection surface is attached to the flange portion 13 in a state of being separated from the first diaphragm portion 12. For this reason, the transmission of force and strain from the second strain body 20 to the first strain body 10 is not hindered by the cover body.

  The second diaphragm portion 22 is formed thinner than the second bulk portion 21. More specifically, the second diaphragm portion 22 has a rear end face located on the same plane as the rear end face of the second bulk portion 21 and a front end face located behind the front end face of the second bulk portion 21. It is formed as follows. Moreover, the 2nd diaphragm part 22 exhibits V shape in planar view, as shown to Fig.3 (a). More specifically, the second diaphragm portion 22 is formed on the outer circumferential surface of the second strain body 20 (the rear side of the second strain body 20) along two side surfaces adjacent to each other in the circumferential direction among the side surfaces of the support body 30. It is formed so as to reach the outer peripheral edge of the end face. The 2nd diaphragm part 22 and the 1st diaphragm part 12 have opposed in the front-back direction.

  The second bulk portion 21 occupies most of the second strain body 20. The second bulk portion 21 is formed thick from the rear end surface to the front end surface (power receiving surface) of the second strain body 20. Further, as shown in FIGS. 2 (c) and 3 (a), the second bulk portion 21 includes three portions of the second diaphragm portion 22 and the three support columns 30 from a circular shape in plan view. Presents a cut-out shape.

(Production method)
Next, a manufacturing method of the multi-axis sensor 1A will be described.

  The manufacturing method of the multi-axis sensor 1A includes a first step of forming the first diaphragm portion 12 and the second diaphragm portion 22, and a second step of forming the first strain body 10 and the second strain body 20 that are separated from each other. Including.

  In the first step, first, a cylindrical bulk member extending in the front-rear direction is prepared. The bulk member may be any member that can be cut using a cutting tool such as an end mill (corresponding to the “cutting means” of the present invention). For example, a flexible metal such as aluminum can be used.

  When preparation of the bulk member is completed, cutting is performed from the outer peripheral surface or the top surface of the bulk member by a cutting means to form a cutout portion 41 including three fan-shaped cutouts on the top surface side of the bulk member. By forming the notch portion 41, the front end surfaces of the three support columns 30 and the front end surface of the second diaphragm portion 22 are formed as shown in FIGS. 2 (c) and 3 (a).

  Subsequently, the first groove portion 42 including six grooves extending in the front-rear direction is formed behind the notch portion 41 by cutting from the outer peripheral surface of the bulk member by a cutting means. In the six grooves constituting the first groove portion 42, two adjacent grooves are connected to each other on the center side of the bulk member in a plan view. In other words, the 1st groove part 42 consists of three groove | channels which exhibit V shape in planar cross sectional view. By forming the first groove portion 42 having such a shape, the first diaphragm portion 12 and the second diaphragm portion 22 are formed in the bulk member. Note that either the formation of the notch 41 or the formation of the first groove 42 may be performed first.

  In the second step, the second groove portion 43 that connects the adjacent first groove portions 42 that are not connected on the center side is formed by cutting from the outer peripheral surface of the bulk member by the cutting means. Specifically, the second groove portion 43 is formed in a portion corresponding to the gap between the first bulk portion 11 and the second bulk portion 21. By forming the second groove portion 43 in this manner, the first strain body 10 and the second strain body 20 are separated from each other as shown in FIG.

  Subsequently, cutting is performed from the bottom surface or outer peripheral surface of the bulk member by a cutting means to form the outer peripheral surface of the flange portion 13 and the three support columns 30 (the side surface constituting a part of the outer peripheral surface of the multiaxial sensor 1A). To do. Finally, a multi-axis sensor 1A is completed by providing a detection element on the rear end face of the first strain body 10 and attaching a cover body.

  Eventually, in the present embodiment, the first diaphragm portion 12 constitutes a part of the rear end surface of the first strain body 10, and the outer peripheral surface of the first strain body 10 (the rear end surface of the first strain body 10). Therefore, the first diaphragm portion 12 can be formed on the first strain body 10 by cutting from the outer peripheral surface of the first strain body 10. Therefore, according to the present embodiment, it is possible to provide a low-cost multi-axis sensor 1A in which the first strain body 10, the second strain body 20, and the three support bodies 30 are integrally formed by cutting. it can.

  Furthermore, in the present embodiment, the first strain body 10, the second strain body 20, and the three strut bodies 30 are integrally formed, so that they are added to the force receiving surface of the second strain body 20. The generated force and the strain generated by the force are transmitted to the rear end face of the first strain body 10 efficiently and accurately. Therefore, according to the present embodiment, a high-performance multi-axis sensor 1A having good linearity and low hysteresis can be provided.

(Detection principle)
Next, the principle of detecting six-axis forces (Fx, Fy, Fz, Mx, My, Mz) applied to the force receiving surface using the multi-axis sensor 1A will be specifically described. In this specific example, the X axis, Y axis, and Z axis orthogonal to each other are defined as shown in FIGS. 2 and 5, and the force parallel to the X axis direction is Fx, and the force parallel to the Y axis direction is Fy, Z axis. A force parallel to the direction is Fz, a moment around the X axis is Mx, a moment around the Y axis is My, and a moment around the Z axis is Mz.

  In this specific example, as shown in FIG. 5A, 24 strain gauges R11 to R14, R21 to R24, R31 to R34, R41 to R44, R51 to R54, R61 to R64 are used as detection elements. ing. The strain gauges R11 to R14, R21 to R24, R31 to R34, R41 to R44, R51 to R54, and R61 to R64 have a large resistance value against strain caused by tension, and a resistance value against strain caused by compression. It shall be smaller.

  As shown in FIG. 5 (a), the strain gauges R11, R12, R21, R22, R31, R32, R41, R42, R51, R52, R61, R62 are the rear end face of the first diaphragm portion 12 (strictly speaking, The boundary line between the rear end surface of the first diaphragm portion 12 and the rear end surface of the column 30 and the boundary line between the rear end surface of the first diaphragm portion 12 and the rear end surface of the first bulk portion 11 are disposed. The strain gauges R13, R14, R23, R24, R33, R34, R43, R44, R53, R54, R63, and R64 are dummy gauges that do not contribute to force detection and are arranged on the rear end surface of the first bulk portion 11. .

  FIG. 6A is a cross-sectional view passing through the strain gauges R11, R12, R21, R22 and R31, R32, R41, R42 when a force Fx parallel to the X-axis direction is applied. When Fx is added, the multi-axis sensor 1A is deformed as shown in FIG. 6A, and R11, R21, R32, and R42 are pulled to increase the resistance value. R12, R22, R31, and R41 are compressed and the resistance value decreases. R51, R52, R61, and R62 conform to changes in R11, R12, R21, and R22, and R51 and R61 have increased resistance values, and R52 and R62 have decreased resistance values.

  When a force Fy parallel to the Y-axis direction is applied, R11, R12, R21, R22 and R51, R52, R61, R62 exhibit resistance changes according to R11, R12, R21, R22 when Fx is applied. To do. That is, R11, R21, R52, and R62 are pulled to increase the resistance value. R12, R22, R51, and R61 are compressed and the resistance value decreases. In R31, R32, R41, and R42, since a force is applied at a right angle to the gauge, almost no resistance change occurs.

  FIG. 6B is a cross-sectional view passing through the strain gauges R11, R12, R21, R22 and R31, R32, R41, R42 when a force Fz parallel to the Z-axis direction is applied. When Fz is added, the multi-axis sensor 1A is deformed as shown in FIG. 6B, and R11, R22, R31, and R42 are pulled to increase the resistance value. R12, R21, R32, and R41 are compressed and the resistance value decreases. R51, R52, R61, and R62 conform to changes in R11, R12, R21, and R22, and R51 and R62 have increased resistance values, and R52 and R61 have decreased resistance values.

  FIG. 6C is a cross-sectional view passing through the strain gauges R11, R12, R21, R22 and R31, R32, R41, R42 when the moment Mx about the X axis is applied. When Mx is added, the multi-axis sensor 1A is deformed as shown in FIG. 6C, and R11, R22, R32, and R41 are pulled to increase the resistance value. R12, R21, R31, and R42 are compressed and the resistance value decreases. R51, R52, R61, and R62 conform to changes in R11, R12, R21, and R22, and R51 and R62 have increased resistance values, and R52 and R61 have decreased resistance values.

  FIG. 6D is a cross-sectional view passing through the strain gauges R11, R12, R21, R22 and R31, R32, R41, R42 when the moment My around the Y axis is applied. When My is added, the multi-axis sensor 1A is deformed as shown in FIG. 6D, and R11, R22, R31, and R41 are pulled to increase the resistance value. R12, R21, R32, and R42 are compressed and the resistance value decreases. Since R51, R52, R61, and R62 are positioned symmetrically to the Y axis with R11, R12, R21, and R22, the resistance value of R52 and R61 increases, and the resistance value of R51 and R62 decreases.

  FIG. 6E is a cross-sectional view passing through the strain gauges R11, R12, R21, R22 and R31, R32, R41, R42 when the moment Mz about the Z axis is applied. When Mz is added, the multi-axis sensor 1A is deformed as shown in FIG. 6E, and R12, R22, R32, and R42 are pulled and the resistance value increases. R11, R21, R31, and R41 are compressed and the resistance value decreases. R51, R52, R61, and R62 conform to changes in R11, R12, R21, and R22, and R52 and R62 have increased resistance values, and R51 and R61 have decreased resistance values.

  Table 1 shows a force Fx parallel to the X axis direction, a force Fy parallel to the Y axis direction, a force Fz parallel to the Z axis direction, a moment Mx around the X axis, a moment My around the Y axis, and a moment around the Z axis. The change of the resistance value of the strain gauges R11, R12, R21, R22, R31, R32, R41, R42, R51, R52, R61, and R62 with respect to Mz is shown. + In Table 1 indicates an increase in resistance value,-in Table 1 indicates a decrease in resistance value, and a blank in Table 1 indicates that the resistance value does not change or is very small. Furthermore, in Table 1, it shows that the increase of resistance value is so large that the number of + is large, and it shows that the reduction | decrease of resistance value is so large that the number of-is large.

なお、力およびモーメントを算出する式は上記の式に限られるものではない。この場合、歪ゲージＲ１３、Ｒ１４、Ｒ２３、Ｒ２４、Ｒ３３、Ｒ３４、Ｒ４３、Ｒ４４、Ｒ５３、Ｒ５４、Ｒ６３、Ｒ６４は、不要である。 If the characteristics shown in Table 1 are used, a change in each resistance value of the strain gauges R11, R12, R21, R22, R31, R32, R41, R42, R51, R52, R61, and R62 is measured, so that the multi-axis sensor 1A 6-axis force (Fx, Fy, Fz, Mx, My, Mz) applied to the force receiving surface can be detected. For example, each force and moment can be calculated by the following formula.

The formula for calculating the force and moment is not limited to the above formula. In this case, the strain gauges R13, R14, R23, R24, R33, R34, R43, R44, R53, R54, R63, R64 are unnecessary.

Moreover, you may measure the voltages V1-V6 shown in FIG.5 (b) instead of measuring the change of resistance value. Specifically, the calibration of 6 rows and 6 columns is performed by measuring each voltage characteristic of the voltages V1 to V6 when 6-axis forces (Fx, Fy, Fz, Mx, My, Mz) are applied accurately. A matrix can be obtained. Then, as shown in the following equation, an accurate 6-axis force can be obtained by multiplying each voltage V1 to V6 when an arbitrary force is applied and the calibration matrix.

  The voltages V1 to V6 are measured using, for example, strain gauges R11 to R14, R21 to R24, R31 to R34, R41 to R44, R51 to R54, and R61 to R64, as shown in FIG. 6 is formed, and a predetermined voltage E is applied to one end of each bridge circuit. This bridge circuit is an example, and a strain gauge may be arranged so as to become a 4-active bridge circuit, or a strain gauge may be arranged so as to become a 1-active 3-dummy bridge circuit. .

  In the multi-axis sensor 1A according to the present embodiment, strain gauges R11, R12, R21, R22, R31, R32, R41, R42, R51, R52, R61, R62, and strain gauges R13, R14, R23, R24, R33, Since R34, R43, R44, R53, R54, R63, and R64 can be arranged in the same plane, the work of attaching a strain gauge is easy, and the manufacturing efficiency is high and the cost can be reduced.

  Further, in the multi-axis sensor 1A according to this embodiment, if the signal processing circuit board is arranged in a form facing the surface on which the strain gauge is attached, the terminals of the strain gauge and the signal processing circuit are electrically connected in the shortest distance. Therefore, the effect of suppressing noise can be enhanced.

[Second Embodiment]
(Construction)
FIG. 7 shows a multi-axis sensor 1B according to the second embodiment of the present invention.

  The multi-axis sensor 1B includes a first strain body 110 including a first bulk portion 111, a first diaphragm portion 112, and a flange portion 113, and a second strain body 120 including a second bulk portion 121 and a second diaphragm portion 122. And three support columns 130.

  The multi-axis sensor 1B is mostly common to the multi-axis sensor 1A according to the first embodiment except that the rear end surface of the second diaphragm portion 122 is located on the front end side of the rear end surface of the second bulk portion 121. doing. In other words, in the multi-axis sensor 1B, the three support bodies 130 are longer than the three support bodies 30 of the multi-axis sensor 1A. In this way, by making the column body 130 longer, a smaller force and strain can be transmitted to the rear end face (detection element) of the first strain body 110.

  Therefore, according to the multi-axis sensor 1B, the detection sensitivity of the force and distortion generated by the force can be improved as compared with the multi-axis sensor 1A according to the first embodiment.

(Production method)
Next, a method for manufacturing the multi-axis sensor 1B will be described.

  In the manufacturing method of the multi-axis sensor 1B, the notch portion 141 is formed shallower than the notch portion 41 in the first embodiment, and the third groove portion 144 is formed by cutting from the outer peripheral surface of the bulk member by a cutting means. Except for this, the manufacturing method of the multi-axis sensor 1A is largely the same.

  The third groove portion 144 may be formed as a part of the first groove portion 142 by forming the first groove portion 142 extending forward from the first groove portion 42 in the first embodiment, or the first embodiment. The first groove portion 142 having the same length as the first groove portion 42 may be formed, and may be formed separately from the first groove portion 142 (after the notch portion 41 and in front of the first groove portion 142).

  Thus, the column body 130 longer than the column body 30 in the first embodiment is formed by forming the notch portion 141 shallower than the notch portion 41 in the first embodiment and forming the third groove portion 144. The provided multi-axis sensor 1B can be manufactured. Therefore, according to the manufacturing method according to the present embodiment, the multi-axis sensor 1B having higher detection sensitivity than the multi-axis sensor 1A manufactured by the manufacturing method according to the first embodiment can be manufactured.

[Third Embodiment]
(Construction)
8 and 9 show a multi-axis sensor 1C according to a third embodiment of the present invention.

  The multi-axis sensor 1C includes a first strain body 210 including a first bulk portion 211 and a first diaphragm portion 212, a second strain body 220 including a second bulk portion 221 and a second diaphragm portion 222, and three The post body 230 is provided. The rear end surface of the first strain body 210 is a detection surface, and the front end surface of the second strain body 220 is a force receiving surface.

  The three support columns 230 extend in the front-rear direction between the rear end surface (detection surface) of the first strain body 210 and the front end surface of the second diaphragm portion 222 of the second strain body 220. The three support columns 230 have two side surfaces facing in the circumferential direction formed in parallel, and have a rectangular shape in plan view and bottom view (see FIGS. 8C and 8F). Further, a through hole 240 is formed in the center of the first strain body 210 and the second strain body 220.

  The first diaphragm portion 212 has a rear end surface located on the same plane as the rear end surface of the first bulk portion 211 and the rear end surface of the support body 230, and the front end surface is located behind the front end surface of the first bulk portion 211. It is formed to do. As shown in FIG. 8 (f), the first diaphragm portion 212 has an outer peripheral surface (first strain generating body) of the first strain generating body 210 along two side surfaces adjacent to each other in the circumferential direction among the side surfaces of the support body 230. It is formed so as to reach the outer peripheral edge of the rear end surface of the body 210. The cross hatch portion in FIG. 8 (f) shows the rear end surface of the first diaphragm portion 212.

  The first bulk portion 211 is formed thicker than the first diaphragm portion 212 from the rear end surface (detection surface) to the front end surface of the first strain body 210. Moreover, the 1st bulk part 211 exhibits a fan shape in bottom view, as shown in FIG.8 (f).

  The second diaphragm portion 222 is formed so that the rear end surface is located on the same plane as the rear end surface of the second bulk portion 221 and the front end surface is located behind the front end surface of the second bulk portion 221. . In addition, the second diaphragm portion 222 is formed on the outer peripheral surface of the second strain body 220 (the outer peripheral edge of the rear end surface of the second strain body 220) along two side surfaces adjacent to each other in the circumferential direction among the side surfaces of the support body 230. ). The 2nd diaphragm part 222 and the 1st diaphragm part 212 are facing the front-back direction.

  The second bulk portion 221 is formed thicker than the second diaphragm portion 222 from the rear end surface to the front end surface (power receiving surface) of the second strain body 220. Moreover, the 2nd bulk part 221 exhibits a fan shape in planar view, as shown in FIG.8 (c).

  After all, in the multi-axis sensor 1C, since the through hole 240 is formed in the center of the first strain body 210 and the second strain body 220, it is easy to form the substantially rectangular support body 230 having parallel portions. Can do. Depending on the setting of the width of the support body 230, the detection sensitivity is lower than that of the multi-axis sensor 1A according to the first embodiment, but the rigidity of the entire sensor can be increased. Further, the central through hole 240 can be used to pass cables from other sensors and devices, and for example, space saving such as reducing the shape of the robot arm can be realized.

(Production method)
Next, a manufacturing method of the multi-axis sensor 1C will be described.

  The manufacturing method of the multi-axis sensor 1C includes a first step of forming the first diaphragm portion 212 and the second diaphragm portion 222, and a second step of forming the first strain body 210 and the second strain body 220 that are separated from each other. Including.

  In the first step, first, a cylindrical bulk member extending in the front-rear direction is prepared, and the through hole 240 is formed in the center of the bulk member by cutting from the top surface or the bottom surface of the bulk member by a cutting means.

  Next, cutting is performed from the outer peripheral surface or the top surface of the bulk member by a cutting means to form a notch portion 241 composed of three substantially rectangular notches having a parallel portion on the top surface side of the bulk member. By forming the notch portion 241, the front end surface of the three support columns 230 and the front end surface of the second diaphragm portion 222 are formed as shown in FIG. 8C.

  Subsequently, the first groove portion 242 including six grooves extending in the front-rear direction is formed behind the notch portion 241 by cutting the outer peripheral surface of the bulk member with a cutting means. The six grooves constituting the first groove portion 242 reach the central through hole 240. In other words, the first groove portion 242 is composed of six grooves having parallel portions in a plan view. By forming the first groove portion 242 in this way, the first diaphragm portion 212 and the second diaphragm portion 222 are formed in the bulk member. Note that either the formation of the notch portion 241 or the formation of the first groove portion 242 may be performed first.

  In the second step, the second groove part 243 connected to the first groove part 242 is formed by cutting from the outer peripheral surface of the bulk member by a cutting means (see FIG. 8B). Specifically, the second groove portion 243 is formed in a portion corresponding to the gap between the first bulk portion 211 and the second bulk portion 221. By forming the second groove portion 243 in this manner, the first strain body 210 and the second strain body 220 are separated from each other. Finally, by providing a detection element on the rear end surface of the first strain body 210, the multi-axis sensor 1C is completed. Also in the present embodiment, the flange portion 13 may be formed and the cover body may be attached as in the first embodiment.

  According to the manufacturing method according to this embodiment, the rigidity of the entire sensor is improved compared to the multi-axis sensor 1A manufactured by the manufacturing method according to the first embodiment, and a cable or the like can be passed through the central through hole 240. The axis sensor 1C can be manufactured.

[Fourth Embodiment]
(Construction)
FIG. 10 shows a multi-axis sensor 1D according to the fourth embodiment of the present invention.

  The multi-axis sensor 1D includes a first strain body 310 including a first bulk portion 311 and a first diaphragm portion 312; a second strain body 320 including a second bulk portion 321 and a second diaphragm portion 322; The support body 330 is provided.

  The column body 330 is formed thicker than the column body 30 in the first embodiment, and has a fan shape in a plan view and a bottom view (see FIG. 10C). When the four support columns 330 are cut at the front end surface of the first strain body 310, the cross-sectional area of the four support members 330 is much larger than the area of the front end surface of the first bulk portion 311. Since the multi-axis sensor 1D includes the four support bodies 330, the strength (rigidity) of the entire sensor can be increased compared to the multi-axis sensor 1A according to the first embodiment.

(Production method)
The multi-axis sensor 1D is manufactured by forming a notch 341 composed of four fan-shaped notches on the top surface side of the bulk member and eight grooves extending in the front-rear direction behind the notch 341 ( Most of the manufacturing method of the multi-axis sensor 1 </ b> A is common except that the first groove portion 342 including four grooves having a V shape in a plan view is formed.

[Fifth Embodiment]
(Construction)
FIG. 11 shows a multi-axis sensor 1E according to the fifth embodiment of the present invention.

  The multi-axis sensor 1E includes a first strain body 410 including a first bulk part 411 and a first diaphragm part 412; a second strain body 420 including a second bulk part 421 and a second diaphragm part 422; The post body 430 is provided. The rear end surface of the first strain body 410 is a detection surface, and the front end surface of the second strain body 420 is a force receiving surface.

  In the multi-axis sensor 1E, since the six support columns 430 are provided, the cutting process is more complicated than the multi-axis sensor 1D according to the fourth embodiment, but the detection sensitivity is higher than that of the multi-axis sensor 1D. The strength of the entire sensor can be increased while suppressing the decrease.

(Production method)
The multi-axis sensor 1E is manufactured by forming notches 441 made of six fan-shaped notches on the top surface side of the bulk member, and twelve grooves extending in the front-rear direction behind the notches 441 ( Except for forming the first groove portion 442 composed of six grooves having a V shape in a plan view, the manufacturing method of the multi-axis sensor 1D is largely the same.

[Sixth Embodiment]
(Construction)
12 and 13 show a multi-axis sensor 1F according to a sixth embodiment of the present invention.

  The multi-axis sensor 1F includes a first strain body 510 including a first bulk portion 511, a first diaphragm portion 512, and a flange portion 513, and a second strain body 520 including a second bulk portion 521 and a second diaphragm portion 522. And three support columns 530. The rear end surface of the first strain body 510 is a detection surface, and the front end surface of the second strain body 520 is a force receiving surface.

  The three support columns 530 extend in the front-rear direction between the rear end surface of the first strain body 510 and the front end surface of the second diaphragm portion 522 of the second strain body 520. As shown in FIG. 13A, each of the three support members 530 has four side surfaces, and faces the circumferential direction of the multiaxial sensor 1F (first strain body 510) among the four side surfaces. Both of the two side surfaces are flat. The two side surfaces facing the radial direction of the multi-axis sensor 1F (first strain body 510) are the outer side surfaces between the rear end surface of the first strain body 510 and the front end surface of the first strain body 510. The plane and the inner side surface are curved surfaces, and both are curved surfaces between the front end surface of the first strain body 510 and the front end surface of the second diaphragm portion 522.

  Further, as shown in FIGS. 12C and 13A, the multi-axis sensor 1F is formed with a communication hole 545 for separating the column body 530 from the first bulk part 511 and the second bulk part 521. Has been. The cross section of the communication hole 545 is not limited to a circle and may be a long hole or the like.

  The first diaphragm portion 512 has a rear end surface located on the same plane as the rear end surface of the first bulk portion 511 and the rear end surface of the column body 530, and the front end surface is located behind the front end surface of the first bulk portion 511. It is formed to do. Further, the first diaphragm portion 512 has an outer peripheral surface of the first strain body 510 (the first strain body 510 along the two side surfaces adjacent to each other in the circumferential direction and the side surface on the radially inner side among the side surfaces of the support body 530. The outer peripheral edge of the rear end face is formed.

  The first bulk portion 511 is formed thicker than the first diaphragm portion 512 from the rear end surface to the front end surface of the first strain body 510. The flange portion 513 is formed at the front end of the outer peripheral surface of the first bulk portion 511. The circle connecting the outer peripheral surface of the flange portion 513 has the same diameter as the circle connecting the outer peripheral surface of the second strain body 520. A cover body (not shown) that covers the detection surface is attached to the flange portion 513 in a state of being separated from the first diaphragm portion 512.

  The second diaphragm portion 522 is formed such that the rear end surface is located on the same plane as the rear end surface of the second bulk portion 521 and the front end surface is located behind the front end surface of the second bulk portion 521. . The second diaphragm portion 522 extends along the two side surfaces adjacent to each other in the circumferential direction among the side surfaces of the column body 530 from the communication hole 545 to the outer circumferential surface of the second strain body 520 (the rear end surface of the second strain body 520). It is formed to reach the outer peripheral edge). The second diaphragm portion 522 and the first diaphragm portion 512 are opposed to each other in the front-rear direction. The second bulk portion 521 is formed thick from the rear end surface to the front end surface (power receiving surface) of the second strain body 520.

  Since the multi-axis sensor 1F according to the present embodiment includes three support columns 530 having four side surfaces, the overall strength (rigidity) of the sensor is increased as compared to the multi-axis sensor 1A according to the first embodiment. Can be made.

(Production method)
Next, a manufacturing method of the multi-axis sensor 1F will be described.

  The manufacturing method of the multi-axis sensor 1F includes a first step of forming the first diaphragm portion 512 and the second diaphragm portion 522, and a second step of forming the first strain body 510 and the second strain body 520 that are separated from each other. Including.

  In the first step, first, a cylindrical bulk member extending in the front-rear direction is prepared, and cutting is performed from the outer peripheral surface or the top surface of the bulk member by a cutting means, and three notches are formed on the top surface side of the bulk member. A notch portion 541 is formed. By forming the notch part 541, the front end face of the three support columns 530 and the front end face of the second diaphragm part 522 are formed.

  Subsequently, the first groove portion 542 including six grooves extending in the front-rear direction is formed behind the notch portion 541 by cutting the outer peripheral surface of the bulk member with a cutting means. The six groove portions constituting the first groove portion 542 are formed so that the distance from each other becomes closer toward the center side of the bulk member. Further, cutting is performed from the top surface of the bulk member by a cutting means to form a communication hole 545 communicating with the notch portion 541 and the two first groove portions 542 (see FIGS. 13A and 13B). Thereby, the 1st diaphragm part 512 and the 2nd diaphragm part 522 are formed in a bulk member, and two side surfaces adjacent to the circumferential direction among the side surfaces of the support | pillar body 530, and a side surface inside radial direction are formed. Note that any of the formation of the notch portion 541, the formation of the first groove portion 542, and the formation of the communication hole 545 may be performed first.

  In the second step, cutting is performed from the outer peripheral surface of the bulk member by cutting means to form two adjacent first groove portions 542 that are not communicated with each other through the connection holes 545 and second groove portions 543 that are connected to the communication holes 545. . Specifically, the second groove portion 543 is formed in a portion corresponding to the gap between the first bulk portion 511 and the second bulk portion 521. By forming the second groove portion 543 in this manner, the first strain body 510 and the second strain body 520 are separated from each other as shown in FIG.

  Subsequently, cutting is performed from the bottom surface or the outer peripheral surface of the bulk member by a cutting means to form the outer peripheral surfaces of the flange portion 513 and the three support columns 530 (side surfaces constituting a part of the outer peripheral surface of the multiaxial sensor 1F). To do. Finally, the multi-axis sensor 1F is completed by providing a detection element on the rear end surface of the first strain body 510 and attaching a cover body.

[Seventh Embodiment]
FIG. 14 shows a multi-axis sensor 1G according to the seventh embodiment of the present invention.

  As shown in FIG. 14, the multi-axis sensor 1G is a capacitance type sensor, and includes a first strain body 610 including a first bulk portion 611 and a first diaphragm portion 612, a second bulk portion 621, and A second strain body 620 including a second diaphragm portion 622 and four support bodies 630 are provided. A support body 640 is attached to the rear end surface (detection surface) of the first strain body 610 and provided on the detection surface. The displacement electrode 650 and the fixed electrode 660 provided on the support 640 are opposed to each other.

  The displacement electrode 650 includes, for example, electrodes D11 to D15, D21 to D25, D31 to D35, and D41 to D45 arranged as shown in FIG. The fixed electrode 660 also has electrodes D ′ 11 to D ′ 15, D ′ 21 to D ′ 25, D ′ 31 to D ′ 35, D ′ 41 to D (not shown) facing each other similarly to the displacement electrode 650. '45 is arranged, and electrostatic capacitances (capacitors) C11 to C15, C21 to C25, C31 to C35, and C41 to C45 are configured as shown in FIG. In addition, even if the electrode group of either the fixed electrode 660 or the displacement electrode 650 is electrically connected or replaced with one electrode, the capacitances (capacitors) C11 to C15, C21 to C25, C31 to C35, C41 may be used. Since ˜C45 can be configured, the essence of the invention is not lost.

Generally, the capacitance C of a capacitor is
C = εS / d ε: Dielectric constant S: Area of opposing electrodes d: Expressed by distance between electrodes. In the present invention, ε and S can be considered to be constant, but the interelectrode distance d changes upon receiving a force, so the capacitance C changes with the interelectrode distance d.

  As shown in FIG. 17A, when a force Fx parallel to the X axis is applied, the distance between the electrodes D11 and D'11 and D31 and D'31 decreases, so that the capacitances C11 and C31 increase. Since the distances between the electrodes D12 and D'12 and D32 and D'32 are increased, the capacitances C12 and C32 are decreased, and the electrodes D13 and D'13, D14 and D'14, D15 and D'15, and the electrodes Since the distances between D33 and D'33, D34 and D'34, and D35 and D'35 hardly change, the capacitances C13, C14, C15, C33, C34, and C35 hardly change. The same can be said for symmetry when a force Fy parallel to the Y-axis is applied. When a force Fz parallel to the Z-axis is applied, displacement occurs as shown in FIG. 17B, and the capacitances C11 to C15 and C31 to C35 decrease.

  When the moment My around the Y-axis is applied, the displacement occurs as shown in FIG. 18A, so that the capacitances C11 to C15 increase and the capacitances C31 to C35 decrease. The same can be said from the symmetry when the moment Mx about the X axis is added. When the moment Mz about the Z axis is applied, the displacement is made as shown in FIG. 18B, so that the capacitance C13 increases, the capacitance C14 decreases, and the capacitances C11, C12, C15 are almost all. It does not change.

  Table 2 shows the relationship between the above force and each capacitance. In Table 2, + indicates an increase in capacitance,-indicates a decrease in capacitance, and a blank indicates little change. When a reverse force is applied, the signs of + and-are switched.

なお、力およびモーメントを算出する式は上記の式に限られるものではない。また、適当な手段を用いて静電容量Ｃ１１〜Ｃ１５、Ｃ２１〜Ｃ２５、Ｃ３１〜Ｃ３５、Ｃ４１〜Ｃ４５を電圧または電流に変換して演算を行ってもよい。 From the characteristics shown in Table 2, six-axis forces (Fx, Fy, Fz, Mx, My, Mz) can be obtained, for example, by the following equation.

The formula for calculating the force and moment is not limited to the above formula. Moreover, you may calculate by converting the electrostatic capacitance C11-C15, C21-C25, C31-C35, C41-C45 into a voltage or an electric current using a suitable means.

  In the multi-axis sensor 1G, the structure of the sensor such as the first strain body 610 and the second strain body 620 is made of a conductive material such as metal, so that the electrodes D11 to D15, D21 to D25, D31 to D35, A common electrode corresponding to D41 to D45 may be used. In this case, the electrodes D11 to D15, D21 to D25, D31 to D35, and D41 to D45 are unnecessary, and the cost can be reduced.

  Corresponding to electrodes D′ 11 to D′ 15, D′ 21 to D′ 25, D′ 31 to D′ 35, and D′ 41 to D′ 45 by configuring the support 640 with a conductive material such as metal. It can also be used as a common electrode. In this case, the electrodes D'11 to D'15, D'21 to D'25, D'31 to D'35, and D'41 to D'45 are unnecessary, and the cost can be reduced.

  In this embodiment, electrodes constituting a total of 20 capacitances C11 to C15, C21 to C25, C31 to C35, and C41 to C45 are provided. Can be sought. For this, for example, the configuration disclosed in Japanese Patent Application Laid-Open No. 2008-96229 can be applied. A method for obtaining a six-axis force with higher accuracy (see, for example, paragraphs [0049] to [0053] of JP-A-2008-96229) is also applicable to the present invention.

  As mentioned above, although each embodiment of the multi-axis sensor concerning the present invention was described, the present invention is not limited to each above-mentioned embodiment.

  In the present invention, the first diaphragm portion constitutes a part of the rear end surface (detection surface) of the first strain body and reaches the outer peripheral edge of the rear end surface of the first strain body. If the member can be cut to form the first strain body, the second strain body, and the support body integrally, the shape, material, number of support bodies, and the like can be changed as appropriate.

  In the present invention, a multi-axis sensor is manufactured by cutting a cylindrical bulk member with a cutting means. However, for example, a multi-axis sensor may be manufactured by cutting a prismatic bulk member. That is, in the present invention, a multi-axis sensor can be manufactured from a columnar bulk member.

  In the present invention, a strain gauge and a capacitance (capacitor) are taken up as examples of the force detection element, but a piezoresistive element or a pressure-sensitive resistance ink may be used.

1A to 1G Multi-axis sensor 10, 110, 210, 310, 410, 510, 610 First strain body 11, 111, 211, 311, 411, 511, 611 First bulk part 12, 112, 212, 312, 412 512, 612 First diaphragm part 13, 113, 513 Flange part 20, 120, 220, 320, 420, 520, 620 Second strain body 21, 121, 221, 321, 421, 521, 621 Second bulk part 22, 122, 222, 322, 422, 522, 622 Second diaphragm part 30, 130, 230, 330, 430, 530, 630 Prop body 41, 141, 241, 341, 441, 541 Notch part 42, 142, 242, 342, 442, 542 First groove 43, 143, 243, 343, 443, 543 Second groove 1 4 third groove 240 through hole 545 communicating hole

Claims (11)

A first strain body including a first bulk part and a first diaphragm part formed thinner than the first bulk part, and having a rear end face provided with a detection element;
A second strain body including a second bulk section and a second diaphragm section facing the first diaphragm section and formed thinner than the second bulk section, and having a front end face attached to a measurement target; ,
A column body connecting the first diaphragm part and the second diaphragm part;
The first diaphragm portion constitutes a part of the rear end surface of the first strain body and reaches the outer periphery of the rear end surface of the first strain body,
The first strain body and the second strain body are disposed apart from each other,
The multi-axis sensor, wherein the first strain body, the second strain body, and the support body are integrally formed by cutting a single member. A cover body covering the rear end surface;
2. The multi-axis sensor according to claim 1, wherein the cover body is attached to a flange portion formed on an outer peripheral surface of the first bulk portion, and is separated from the first diaphragm portion. 3. The multi-axis sensor according to claim 1, wherein the second diaphragm portion has a rear end surface positioned in front of a rear end surface of the second bulk portion. The cross-sectional area of the said support | pillar body becomes larger than the area of the front-end surface of a said 1st bulk part, when the said support | pillar body is cut | disconnected by the front-end surface of the said 1st bulk part. The multi-axis sensor according to any one of the above. The support body has four side surfaces,
Of the four side surfaces, two side surfaces facing the circumferential direction of the first strain body are both flat surfaces, and two side surfaces facing the radial direction of the first strain body are at least on the inner side. The multi-axis sensor according to claim 1, wherein the side surface is a curved surface. 6. The multi-axis sensor according to claim 1, wherein a through-hole extending in the front-rear direction is formed at a center of the first strain body and the second strain body. . A rear end surface of the first strain body is formed flat;
The multi-axis sensor according to claim 1, wherein the plurality of detection elements are provided on the same plane. The multi-axis sensor according to any one of claims 1 to 7, wherein the detection element has a resistance value that changes when a strain is generated on a rear end surface of the first strain body. The multi-axis sensor according to claim 1, wherein the detection element has a capacitance value that changes when a rear end surface of the first strain body is displaced. A first strain body having a first diaphragm portion on the rear end face side, and a second strain body having a second diaphragm portion disposed in front of the first strain body and spaced apart from the first strain body. A multi-axis sensor comprising: a body; and a support body extending in the front-rear direction connecting the first diaphragm portion and the second diaphragm portion,
Cutting from the outer peripheral surface or front end surface side of the columnar bulk member extending in the front-rear direction by the cutting means to form a notch on the front end surface side of the bulk member, and the outer periphery of the bulk member by the cutting means A first step of forming the first diaphragm part and the second diaphragm part by cutting from the surface side and forming a first groove part extending in the front-rear direction behind the notch part;
By cutting from the outer peripheral surface side of the bulk member by the cutting means to form a second groove portion connected to the first groove portion, the first strain body and the second strain body separated from each other are formed. And a second step of forming the multi-axis sensor. In the first step, cutting is performed from the front end surface side of the bulk member by the cutting means to form a communication hole communicating with the notch and the first groove, or the notch and the first Prior to forming one groove portion, the column body having at least four side surfaces is formed by cutting from the front end surface or rear end surface side of the bulk member by the cutting means to form a through hole extending in the front-rear direction. The method for manufacturing a multi-axis sensor according to claim 10, further comprising a step of forming.

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