Force sensor

Abstract

This invention provides a force sensor comprising an annular housing, a top cover and a base respectively fixed to one end of the housing, a loading platform fixed to the top cover near the base and spaced apart from the housing and the base, at least three force-measuring beam assemblies spaced apart from each other around the periphery of the loading platform, and a first sensor device and a second sensor device disposed on each force-measuring beam assembly. Each force-measuring beam assembly includes a horizontal force-measuring beam fixed to the periphery of the loading platform and a vertical force-measuring beam fixed to the loading platform near the base. The horizontal and vertical force-measuring beams in each force-measuring beam assembly are perpendicular to each other and located in the same plane. All force-measuring beam assemblies are rotationally symmetrically distributed. The force sensor of this invention can improve its decoupling effect and simplify data processing during measurement.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and more particularly to a force sensor. Background Technology

[0002] A six-dimensional force sensor is a measuring device that can simultaneously measure three force components and three torque components of an object in three-dimensional space. It mainly includes a housing, a loading platform housed in the housing, a force measuring beam connecting the loading platform and the housing, and a force measuring element fixed on the force measuring beam.

[0003] The structure of a six-dimensional force sensor largely determines its performance, while the form and arrangement of the force-measuring elements directly affect its sensitivity, stiffness, linearity, dynamic performance, and interdimensional coupling.

[0004] To achieve miniaturization and improve stiffness, most six-dimensional force sensors in related technologies adopt an integrated structure. The force measuring element of such six-dimensional force sensors often has a certain degree of stress coupling and cannot be completely decoupled, thus affecting the actual measurement effect of the six-dimensional force sensor.

[0005] Therefore, it is necessary to provide a new force sensor to solve the above-mentioned technical problems. Summary of the Invention

[0006] The purpose of this invention is to provide a new force sensor to solve the problem that stress coupling exists at the position of the force measuring element in the integrated six-dimensional force sensor of the related technology, and cannot be completely decoupled, thus affecting the actual measurement effect of the six-dimensional force sensor.

[0007] The present invention provides a force sensor, which includes an annular housing, a top cover and a base respectively covering and fixed to both ends of the housing, a loading platform fixed to the top cover near the base and spaced apart from the housing and the base, at least three force measuring beam assemblies disposed on the periphery of the loading platform and spaced apart from each other, and a first sensor device and a second sensor device disposed on the force measuring beam assemblies.

[0008] The plane containing the loading platform is defined as a horizontal plane. Each force-measuring beam assembly includes a horizontal force-measuring beam fixed to the periphery of the loading platform and extending in a direction parallel to the horizontal plane, and a vertical force-measuring beam fixed to the side of the loading platform near the base and extending towards the base in a direction perpendicular to the horizontal plane. The end of the horizontal force-measuring beam away from the loading platform extends to form a fixed connection with the housing, and the end of the vertical force-measuring beam away from the loading platform extends to form a fixed connection with the base. The horizontal and vertical force-measuring beams in each force-measuring beam assembly are arranged perpendicularly to each other and are located in the same plane. A first sensor device for detecting the axial force of the corresponding horizontal force-measuring beam is fixed on the surface of each horizontal force-measuring beam, and a second sensor device for detecting the axial force of the corresponding vertical force-measuring beam is fixed on the surface of each vertical force-measuring beam. All the force-measuring beam assemblies are rotationally symmetrical about the center of the loading platform.

[0009] Preferably, the horizontal and vertical force-measuring beams in each force-measuring beam assembly are both square prisms; one or both ends of each horizontal force-measuring beam are respectively provided with a first flexible hinge structure; the first flexible hinge structure includes two first grooves arranged axially symmetrically formed by indentation of two opposite sides of the horizontal force-measuring beam, and two second grooves arranged axially symmetrically formed by indentation of the other two opposite sides of the horizontal force-measuring beam, the first grooves and the second grooves being arranged at intervals along the extension direction of the horizontal force-measuring beam;

[0010] Each of the vertical force measuring beams has a second flexible hinge structure at one or both ends; the second flexible hinge structure includes two third grooves arranged symmetrically by indentation of two opposite sides of the vertical force measuring beam, and two fourth grooves arranged symmetrically by indentation of the other two opposite sides of the vertical force measuring beam, the third grooves and the fourth grooves being arranged at intervals along the extension direction of the vertical force measuring beam.

[0011] Preferably, the first groove includes a first inclined segment extending inwardly from two opposite sides of the horizontal force-measuring beam and inclined toward the second groove, a first vertical segment extending inwardly from the first inclined segment along a direction perpendicular to the extension of the horizontal force-measuring beam, and a first circular groove extending inwardly from the first vertical segment; the second groove includes a second inclined segment extending inwardly from two other opposite sides of the horizontal force-measuring beam and inclined toward the first groove, a second vertical segment extending inwardly from the second inclined segment along a direction perpendicular to the extension of the horizontal force-measuring beam, and a second circular groove extending inwardly from the second vertical segment; wherein the inclination direction of the first inclined segment is opposite to the inclination direction of the second inclined segment;

[0012] The third groove includes a third inclined segment that is recessed inward from two opposite sides of the vertical force-measuring beam and extends inclined towards the fourth groove; a first horizontal segment that extends inward from the third inclined segment along a direction perpendicular to the extension of the vertical force-measuring beam; and a third circular groove that extends inward from the first horizontal segment. The fourth groove includes a fourth inclined segment that is recessed inward from two other opposite sides of the vertical force-measuring beam and extends inclined towards the third groove; a second horizontal segment that extends inward from the fourth inclined segment along a direction perpendicular to the extension of the vertical force-measuring beam; and a fourth circular groove that extends inward from the second horizontal segment. The inclination direction of the third inclined segment is opposite to that of the fourth inclined segment.

[0013] Preferably, the loading platform includes a cylindrical loading platform body and a plurality of columnar square beams extending radially from the outer periphery of the loading platform body towards the housing. One end of the loading platform body near the top cover is fixed to the top cover. The end of each square beam away from the loading platform body is spaced apart from the housing. The plurality of square beams are equally spaced on the outer periphery of the loading platform body. The number of square beams is the same as the number of force-measuring beam assemblies. Each square beam is fixedly connected to a horizontal force-measuring beam, and the extension direction of the horizontal force-measuring beam is perpendicular to the extension direction of the corresponding square beam. In each force-measuring beam assembly, the horizontal force-measuring beam and the vertical force-measuring beam are respectively fixed to two adjacent sides of one of the square beams, and the vertical force-measuring beam is fixed to the side of the square beam near the base.

[0014] Preferably, the loading platform body has a plurality of recessed and spaced-apart pin holes and a plurality of screw holes on the side near the top cover; the top cover has pins protruding into the plurality of pin holes on the side near the loading platform body; the force sensor also includes screws, and the top cover has through holes corresponding to the screw holes, and the screws pass through the through holes to the corresponding screw holes to form a detachable fixed connection for fixing the loading platform body to the top cover.

[0015] Preferably, the housing is provided with a boss that protrudes from the inner periphery of the housing toward the corresponding horizontal force measuring beam at the position of each horizontal force measuring beam; the end of each horizontal force measuring beam away from the loading platform body is fixed to the corresponding boss.

[0016] Preferably, the force sensor further includes a ring-shaped waterproof pad, which is clamped and fixed between the housing and the top cover to form a waterproof sealing structure.

[0017] Preferably, the first sensor device is fixed to each of the opposite two or four sides of each horizontal force measuring beam; and the second sensor device is fixed to each of the opposite two or four sides of each vertical force measuring beam.

[0018] Preferably, the first sensor device and the second sensor device are any one of a resistance strain gauge, a capacitance strain gauge, a piezoelectric strain gauge, and a fiber optic strain gauge.

[0019] Preferably, the base includes a base body fixed to the housing and a protrusion extending from the base body near the top cover toward the top cover; the end of each vertical force measuring beam away from the loading platform is fixed to the protrusion near the top cover.

[0020] Preferably, the force measuring beam assembly comprises three or four beams.

[0021] Compared with related technologies, the force sensor in this invention defines the horizontal and vertical force measuring beams in each force measuring beam assembly as perpendicular to each other and located in the same plane, and defines each horizontal force measuring beam as extending in a direction parallel to the horizontal plane. This is equivalent to forming a parallel force sensor with horizontal and vertical orthogonal arrangement. The orthogonally distributed force measuring beams can achieve decoupling of force and torque measurement in the orthogonal plane of space, which greatly improves the decoupling effect of the force sensor and simplifies data processing during the measurement process. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0023] Figure 1 This is a three-dimensional structural diagram of the force sensor provided in Embodiment 1 of the present invention, excluding the screw, the first sensor device, and the second sensor device;

[0024] Figure 2 This is a partial exploded view of the force sensor provided in Embodiment 1 of the present invention, excluding screws;

[0025] Figure 3 For along Figure 1 Cross-sectional view of line AA in the middle;

[0026] Figure 4 This is an exploded view of the top cover, loading platform, and screws in the force sensor provided in Embodiment 1 of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of one set of force measuring beam assemblies of the force sensor provided in Embodiment 1 of the present invention;

[0028] Figure 6 This is a three-dimensional structural diagram of the loading platform, force measuring beam assembly, first sensor device, and second sensor device in the force sensor provided in Embodiment 1 of the present invention.

[0029] Figure 7 This is a schematic diagram of the loading platform, horizontal force measuring beam, and vertical force measuring beam in the force sensor provided in Embodiment 2 of the present invention.

[0030] Among them, 100 is a force sensor; 1 is a housing; 11 is a boss; 2 is a top cover; 21 is a pin; 22 is a through hole; 3 is a base; 31 is a base body; 32 is a protrusion; 4 is a loading platform; 41 is a loading platform body; 411 is a pin hole; 412 is a screw hole; 42 is a square beam; 5 is a force measuring beam assembly; 51 is a horizontal force measuring beam; 511 is a first flexible hinge structure; 5111 is a first groove; 51111 is a first inclined section; 51112 is a first vertical section; 51113 is a first circular groove; 5112 is a second groove. 51121, Second inclined section; 51122, Second vertical section; 51123, Second circular groove; 52, Vertical force measuring beam; 521, Second flexible hinge structure; 5211, Third groove; 52111, Third inclined section; 52112, First horizontal section; 52113, Third circular groove; 5212, Fourth groove; 52121, Fourth inclined section; 52122, Second horizontal section; 52123, Fourth circular groove; 6, Waterproof pad; 7, First sensor device; 8, Second sensor device; 9, Screw. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1

[0033] This invention provides a force sensor 100, combined with Figures 1 to 6 As shown, it includes a ring-shaped housing 1, a top cover 2 and a base 3 respectively covering and fixed to both ends of the housing 1, a loading platform 4 fixed to the side of the top cover 2 near the base 3 and spaced apart from the housing 1 and the base 3, at least three force measuring beam assemblies 5 arranged around the periphery of the loading platform 4 and spaced apart from each other, and a first sensor device 7 and a second sensor device 8 provided on the force measuring beam assembly 5.

[0034] In this design, the plane containing the loading platform 4 is defined as a horizontal plane. Each force-measuring beam assembly 5 includes a horizontal force-measuring beam 51 fixed to the periphery of the loading platform 4 and extending in a direction parallel to the horizontal plane, and a vertical force-measuring beam 52 fixed to the side of the loading platform 4 near the base 3 and extending towards the base 3 in a direction perpendicular to the horizontal plane. The end of the horizontal force-measuring beam 51 away from the loading platform 4 extends to form a fixed connection with the housing 1, and the end of the vertical force-measuring beam 52 away from the loading platform 4 extends to form a fixed connection with the base 3. The horizontal force-measuring beam 51 and the vertical force-measuring beam 52 in each force-measuring beam assembly 5 are arranged perpendicularly to each other and are located in the same plane. Since only two ends of the horizontal force-measuring beam 51 and the vertical force-measuring beam 52 are fixed to other structures, they will deform under stress.

[0035] Each horizontal force-measuring beam 51 has a first sensor device 7 fixed on its surface for detecting the axial force of the corresponding horizontal force-measuring beam 51, and each vertical force-measuring beam 52 has a second sensor device 8 fixed on its surface for detecting the axial force of the corresponding vertical force-measuring beam 52.

[0036] All force-measuring beam assemblies 5 are distributed rotationally symmetrically around the center of the loading platform 4. Rotational symmetry means that a shape (i.e., all force-measuring beam assemblies 5) can coincide with the original shape after rotating around a point (i.e., the center point of the plane containing the loading platform 4) by a certain angle. In this embodiment, there are four force-measuring beam assemblies 5, corresponding to a rotation angle of 360° / 4. If there are three force-measuring beam assemblies 5, the rotation angle is 360° / 3, and so on for other quantities.

[0037] The two ends of the horizontal force-measuring beam 51 can be fixed to the loading platform 4 and the housing 1 by means of bolts or welding; the two ends of the vertical force-measuring beam 52 can be fixed to the loading platform 4 and the base 3 by means of bolts or welding.

[0038] In this embodiment, both the horizontal force-measuring beam 51 and the vertical force-measuring beam 52 are square prisms. Of course, depending on actual needs, the horizontal force-measuring beam 51 and the vertical force-measuring beam 52 can also be designed into other shapes, such as circles, trapezoids, etc.

[0039] For each horizontal force-measuring beam 51, the housing 1 is provided with a boss 11 that protrudes from the inner circumference of the housing 1 toward the corresponding horizontal force-measuring beam 51. In this embodiment, multiple bosses 11 are connected in sequence as a whole; the end of each horizontal force-measuring beam 51 away from the loading platform body 41 is fixed to the corresponding boss 11. This design can shorten the extension length of the horizontal force-measuring beam 51, thereby improving its rigidity.

[0040] The base 3 includes a base body 31 fixed to the housing 1 and a protrusion 32 extending from the side of the base body 31 near the top cover 2 towards the top cover 2; the end of each vertical force-measuring beam 52 away from the loading platform 4 is fixed to the side of the protrusion 32 near the top cover 2. This design allows the base body 31 to be more stably fixed to the housing 1 by screws or bolts, while the protruding design of the protrusion 32 can shorten the length of the vertical force-measuring beam 52 to improve its rigidity.

[0041] The loading platform 4 includes a cylindrical loading platform body 41 and a plurality of columnar square beams 42 extending radially from the outer periphery of the loading platform body 41 towards the housing 1. The end of the loading platform body 41 near the top cover 2 is fixed to the top cover 2. The end of each square beam 42 away from the loading platform body 41 is spaced apart from the housing 1. The plurality of square beams 42 are evenly spaced on the outer periphery of the loading platform body 41. In this embodiment, there are four square beams 42, arranged in a cross shape. Depending on actual needs, the square beams 42 can also be designed in other shapes such as circles or trapezoids.

[0042] The top cover 2 can also be provided with a protruding structure at the position corresponding to the loading platform body 41, so as to form a fixed connection with the loading platform body 41 and the square beam 42.

[0043] The number of square beams 42 is the same as the number of force-measuring beam assemblies 5. Each square beam 42 is fixedly connected to a horizontal force-measuring beam 51, and the extension direction of the horizontal force-measuring beam 51 is perpendicular to the extension direction of the corresponding square beam 42. In each force-measuring beam assembly 5, the horizontal force-measuring beam 51 and the vertical force-measuring beam 52 are respectively fixed to two adjacent sides of one of the square beams 42, and the vertical force-measuring beam 52 is fixed to the side of the square beam 42 closest to the base 3. This design can shorten the length of the horizontal force-measuring beam 51 and the vertical force-measuring beam 52, thereby improving their rigidity, while also facilitating that the vertical force-measuring beam 52 of the horizontal force-measuring beam 51 in the same force-measuring beam assembly 5 are arranged in the same plane and perpendicular to each other.

[0044] The loading platform body 41 has a plurality of recessed and spaced-apart pin holes 411 and a plurality of screw holes 412 on the side near the top cover 2; the top cover 2 has pins 21 protruding into the plurality of pin holes 411 on the side near the loading platform body 41; Figure 4As shown, the force sensor 100 also includes screws 9. The top cover 2 has through holes 22 corresponding to the screw holes 412. The screws 9 pass through the through holes 22 to the corresponding screw holes 412 to form a detachable fixed connection, used to fix the loading platform body 41 to the top cover 2. This design not only allows for quick positioning of the loading platform 4 and the top cover 2 through the pin holes 411 and pins 21, but also allows for more stable fixing of the loading platform 4 to the top cover 2 through the screws 9. In this embodiment, there are two pin holes 411 and two pins 21, each with a one-to-one correspondence; there are two screw holes 412, two through holes 22, and two screws 9, with each screw 9 passing through a corresponding through hole 22 and a screw hole 412.

[0045] Each horizontal force-measuring beam 51 has a first flexible hinge structure 511 at both ends. The first flexible hinge structure 511 includes two first grooves 5111 formed by inward indentation of two opposite sides of the horizontal force-measuring beam 51, arranged symmetrically; and two second grooves 5112 formed by inward indentation of the other two opposite sides of the horizontal force-measuring beam 51, also arranged symmetrically. The first grooves 5111 and the second grooves 5112 are spaced apart along the extension direction of the horizontal force-measuring beam 51. This design improves the elasticity of the horizontal force-measuring beam 51, and ideally, the horizontal force-measuring beam 51 can be considered a two-force beam, i.e., it only bears axial tensile force and / or compressive force. Of course, depending on actual needs, the first flexible hinge structure 511 can also be provided only at one end of the horizontal force-measuring beam 51.

[0046] like Figure 5 As shown, the axis of symmetry of the two first grooves 5111 at one end of each horizontal force measuring beam 51 is axis A; the axis of symmetry of the two second grooves 5112 at one end of each horizontal force measuring beam 51 is axis B.

[0047] The first groove 5111 includes a first inclined segment 51111 extending inward from two opposite sides of the horizontal force-measuring beam 51 and inclined towards the second groove 5112; a first vertical segment 51112 extending inward from the first inclined segment 51111 along a direction perpendicular to the horizontal force-measuring beam 51; and a first circular groove 51113 extending inward from the first vertical segment 51112. The second groove 5112 includes a second inclined segment 51121 extending inward from two other opposite sides of the horizontal force-measuring beam 51 and inclined towards the first groove 5111; a second vertical segment 51122 extending inward from the second inclined segment 51121 along a direction perpendicular to the horizontal force-measuring beam 51; and a second circular groove 51123 extending inward from the second vertical segment 51122. The inclination direction of the first inclined segment 51111 is opposite to that of the second inclined segment 51121. This design helps to reduce stress concentration during loading using a smaller flexible hinge structure.

[0048] Each vertical force-measuring beam 52 has a second flexible hinge structure 521 at both ends. The second flexible hinge structure 521 includes two third grooves 5211 formed by inward indentation of two opposite sides of the vertical force-measuring beam 52, arranged symmetrically; and two fourth grooves 5212 formed by inward indentation of the other two opposite sides of the vertical force-measuring beam 52, arranged symmetrically. The third grooves 5211 and fourth grooves 5212 are spaced apart along the extension direction of the vertical force-measuring beam 52. This design improves the elasticity of the vertical force-measuring beam 52, and ideally, the vertical force-measuring beam 52 can be considered a two-force beam, i.e., it only bears axial tensile force and / or compressive force. Of course, depending on actual needs, the second flexible hinge structure 521 can also be provided only at one end of the vertical force-measuring beam 52.

[0049] like Figure 5 As shown, the axis of symmetry of the two third grooves 5211 at one end of each vertical force measuring beam 52 is the C-axis; the axis of symmetry of the two fourth grooves 5212 at one end of each vertical force measuring beam 52 is the D-axis.

[0050] The third groove 5211 includes a third inclined segment 52111 that is recessed inward from two opposite sides of the vertical force-measuring beam 52 and extends inclinedly toward the fourth groove 5212; a first horizontal segment 52112 that extends inward from the third inclined segment 52111 along a direction perpendicular to the extension of the vertical force-measuring beam 52; and a third circular groove 52113 that extends inward from the first horizontal segment 52112. The fourth groove 5212 includes a fourth inclined segment 52121 that is recessed inward from two other opposite sides of the vertical force-measuring beam 52 and extends inclinedly toward the third groove 5211; a second horizontal segment 52122 that extends inward from the fourth inclined segment 52121 along a direction perpendicular to the extension of the vertical force-measuring beam 52; and a fourth circular groove 52123 that extends inward from the second horizontal segment 52122. The inclination direction of the third inclined segment 52111 is opposite to the inclination direction of the fourth inclined segment 52121. This design helps to reduce stress concentration under load when using a smaller, flexible hinge structure.

[0051] The two first grooves 5111 on the horizontal force-measuring beam 51 are formed by recesses on two opposite sides of the horizontal force-measuring beam 51, and also extend through the other two sides of the horizontal force-measuring beam 51, such as... Figure 5 As shown, the two first grooves 5111 are formed by the inward indentation of the left and right sides of the horizontal force measuring beam 51, respectively. At the same time, the first grooves 5111 are both penetrated from the front side of the horizontal force measuring beam 51 to its rear side. The two second grooves 5112 are also set in the same way.

[0052] The two third grooves 5211 and two fourth grooves 5212 on the vertical force measuring beam 52 are similarly set up as the two first grooves 5111 on the horizontal force measuring beam 51.

[0053] Furthermore, for the horizontal force-measuring beam 51, the inclination direction of the first inclined segment 51111 is opposite to the inclination direction of the second inclined segment 51121, combined with... Figure 5 As shown, the first inclined segment 51111 of the first trough 5111 tilts downwards, while the second inclined segment 51121 of the second trough 5112 tilts upwards. It should be noted that when the structure is placed at different angles, the corresponding up, down, left, and right directions also change accordingly, and the principle is the same as described above; the third inclined segment 52111 and the fourth inclined segment 52121 of the vertical force-measuring beam 52 are set in the same way.

[0054] Each horizontal force-measuring beam 51 has a first sensor device 7 fixed to one of its two or four opposite sides; each vertical force-measuring beam 52 has a second sensor device 8 fixed to one of its two or four opposite sides. This design can improve the measurement accuracy of the force sensor 100 by using multiple sensor devices. Of course, depending on actual needs, only one sensor device can be set for each horizontal force-measuring beam 51, and only one sensor device can be set for each vertical force-measuring beam 52.

[0055] In this embodiment, as Figure 6 As shown, each horizontal force-measuring beam 51 is provided with a first sensor device 7 on the side near the top cover 2, and each vertical force-measuring beam 52 is provided with a second sensor device 8 on the side near its corresponding part of the housing 1. That is, each horizontal force-measuring beam 51 is provided with only one first sensor device 7, and each vertical force-measuring beam 52 is provided with only one second sensor device 8.

[0056] The first sensor device 7 and the second sensor device 8 can be any one of a resistance strain gauge, a capacitance strain gauge, a piezoelectric strain gauge, or a fiber optic strain gauge. Of course, other force-measuring devices can also be selected as the sensor devices according to actual needs.

[0057] The force sensor 100 also includes a ring-shaped waterproof gasket 6, which is clamped and fixed between the housing 1 and the top cover 2 to form a waterproof seal. The waterproof gasket 6 is made of soft silicone, soft rubber, etc. This design can improve the waterproof effect between the top cover 2 and the housing 1.

[0058] like Figure 1 As shown in Figure 2, the first direction is set as the X-axis, the second direction as the Y-axis, and the third direction as the Z-axis. The directions of the first direction, the second direction, and the third direction are perpendicular to each other.

[0059] In this embodiment, the force sensor 100 is arranged in a horizontal and vertical orthogonal configuration in space, meaning the planes containing the X and Y axes are orthogonal to the direction of the Z axis. Therefore, when the applied force is Fx, Fy, or Mz, it can be measured by the horizontally arranged horizontal force beam 51, where Fx is the force along the X-axis, Fy is the force along the Y-axis, and Mz is the torque about the Z-axis. When the applied force is Fz, Mx, or My, it can be measured by the vertical force beam 52, where Fz is the force along the Z-axis, Mx is the torque about the X-axis, and My is the torque about the Y-axis. This not only achieves accurate measurement of six-dimensional forces in principle but also improves its decoupling effect.

[0060] Compared with related technologies, the force sensor 100 in this invention defines the horizontal force measuring beam 51 and the vertical force measuring beam 52 in each force measuring beam assembly 5 as perpendicular to each other and located in the same plane, and defines each horizontal force measuring beam 51 as extending in a direction parallel to the horizontal plane. This is equivalent to forming a parallel force sensor 100 with horizontal and vertical orthogonal arrangement. The orthogonally distributed force measuring beams can achieve decoupling of force and torque measurement in the orthogonal plane of space, which greatly improves the decoupling effect of the force sensor 100 and simplifies data processing during the measurement process.

[0061] Example 2

[0062] The force sensor in this embodiment differs from the force sensor 100 in Embodiment 1 in that it combines... Figure 7 As shown, the force sensor 100 in this embodiment has three force measuring beam assemblies 5.

[0063] Since the force sensor in this embodiment only changes the number of force measuring beam components 5, it can achieve the same technical effect as the force sensor 100 in Embodiment 1, which will not be elaborated here.

[0064] The above are merely embodiments of the present invention. It should be noted that those skilled in the art can make improvements without departing from the inventive concept of the present invention, but these improvements all fall within the protection scope of the present invention.

Claims

1. A force sensor, comprising an annular housing, a top cover and a base respectively covering and fixed to both ends of the housing, a loading platform fixed to the top cover near the base and spaced apart from the housing and the base, at least three force-measuring beam assemblies disposed around the periphery of the loading platform and spaced apart from each other, and a first sensor device and a second sensor device disposed on the force-measuring beam assemblies; characterized in that, The plane containing the loading platform is defined as a horizontal plane. Each force-measuring beam assembly includes a horizontal force-measuring beam fixed to the periphery of the loading platform and extending in a direction parallel to the horizontal plane, and a vertical force-measuring beam fixed to the side of the loading platform near the base and extending towards the base in a direction perpendicular to the horizontal plane. The end of the horizontal force-measuring beam away from the loading platform extends to form a fixed connection with the housing, and the end of the vertical force-measuring beam away from the loading platform extends to form a fixed connection with the base. The horizontal and vertical force-measuring beams in each force-measuring beam assembly are arranged perpendicularly to each other and are located in the same plane. A first sensor device for detecting the axial force of the corresponding horizontal force-measuring beam is fixed on the surface of each horizontal force-measuring beam, and a second sensor device for detecting the axial force of the corresponding vertical force-measuring beam is fixed on the surface of each vertical force-measuring beam. All force-measuring beam assemblies are rotationally symmetrical about the center of the loading platform. The horizontal and vertical force measuring beams in each force measuring beam assembly are all square prisms; one or both ends of each horizontal force measuring beam are provided with a first flexible hinge structure; the first flexible hinge structure includes two first grooves formed by inward indentation of two opposite sides of the horizontal force measuring beam and two second grooves formed by inward indentation of the other two opposite sides of the horizontal force measuring beam and arranged symmetrically, the first grooves and the second grooves being arranged at intervals along the extension direction of the horizontal force measuring beam; Each of the vertical force measuring beams has a second flexible hinge structure at one or both ends; the second flexible hinge structure includes two third grooves arranged symmetrically by indentation of two opposite sides of the vertical force measuring beam, and two fourth grooves arranged symmetrically by indentation of the other two opposite sides of the vertical force measuring beam, the third grooves and the fourth grooves being arranged at intervals along the extension direction of the vertical force measuring beam.

2. The force sensor as described in claim 1, characterized in that, The first groove includes a first inclined segment that is recessed inward from two opposite sides of the horizontal force-measuring beam and extends inclined towards the second groove, a first vertical segment that extends inward from the first inclined segment along a direction perpendicular to the extension of the horizontal force-measuring beam, and a first circular groove that extends inward from the first vertical segment; the second groove includes a second inclined segment that is recessed inward from two other opposite sides of the horizontal force-measuring beam and extends inclined towards the first groove, a second vertical segment that extends inward from the second inclined segment along a direction perpendicular to the extension of the horizontal force-measuring beam, and a second circular groove that extends inward from the second vertical segment; wherein the inclination direction of the first inclined segment is opposite to the inclination direction of the second inclined segment; The third groove includes a third inclined segment that is recessed inward from two opposite sides of the vertical force-measuring beam and extends inclined towards the fourth groove; a first horizontal segment that extends inward from the third inclined segment along a direction perpendicular to the extension of the vertical force-measuring beam; and a third circular groove that extends inward from the first horizontal segment. The fourth groove includes a fourth inclined segment that is recessed inward from two other opposite sides of the vertical force-measuring beam and extends inclined towards the third groove; a second horizontal segment that extends inward from the fourth inclined segment along a direction perpendicular to the extension of the vertical force-measuring beam; and a fourth circular groove that extends inward from the second horizontal segment. The inclination direction of the third inclined segment is opposite to that of the fourth inclined segment.

3. The force sensor as described in claim 1, characterized in that, The loading platform includes a cylindrical loading platform body and a plurality of rectangular beams extending radially from the outer periphery of the loading platform body towards the housing. The end of the loading platform body near the top cover is fixed to the top cover. The end of each square beam away from the loading platform body is spaced apart from the housing. The plurality of square beams are equally spaced on the outer periphery of the loading platform body. The number of square beams is the same as the number of force measuring beam assemblies. Each square beam is fixedly connected to a horizontal force measuring beam, and the extension direction of the horizontal force measuring beam is perpendicular to the extension direction of the corresponding square beam. In each force measuring beam assembly, the horizontal force measuring beam and the vertical force measuring beam are respectively fixed to two adjacent sides of one of the square beams, and the vertical force measuring beam is fixed to the side of the square beam near the base.

4. The force sensor as described in claim 3, characterized in that, The loading platform body has a plurality of recessed and spaced-apart pin holes and a plurality of screw holes on the side near the top cover; the top cover has pins protruding into the plurality of pin holes on the side near the loading platform body; the force sensor also includes screws, and the top cover has through holes corresponding to the screw holes, and the screws pass through the through holes to the corresponding screw holes to form a detachable fixed connection for fixing the loading platform body to the top cover.

5. The force sensor as described in claim 3, characterized in that, The housing is provided with a boss that protrudes from the inner periphery of the housing toward the corresponding horizontal force measuring beam at the position of each horizontal force measuring beam; the end of each horizontal force measuring beam away from the loading platform body is fixed to the corresponding boss.

6. The force sensor as described in claim 1, characterized in that, The force sensor also includes a ring-shaped waterproof pad, which is clamped and fixed between the housing and the top cover to form a waterproof sealing structure.

7. The force sensor as described in claim 1, characterized in that, The first sensor device is fixed to each of the two or four opposite sides of each horizontal force measuring beam; the second sensor device is fixed to each of the two or four opposite sides of each vertical force measuring beam.

8. The force sensor as described in claim 1, characterized in that, The first sensor device and the second sensor device are any one of resistance strain gauge, capacitance strain gauge, piezoelectric strain gauge and fiber optic strain gauge.

9. The force sensor as described in claim 1, characterized in that, The base includes a base body fixed to the housing and a protrusion extending from the base body near the top cover toward the top cover; the end of each vertical force measuring beam away from the loading platform is fixed to the protrusion near the top cover.

10. The force sensor according to any one of claims 1 to 9, characterized in that, The force-measuring beam assembly comprises three or four beams.

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