A force sensor

Abstract

The present invention discloses a force sensor, which includes: an elastomer, a circuit board and a sensitive element. The elastomer includes a first end and a second end relative to each other. The sensitive element is attached to the end face of the first end. The second end has a force-bearing annular surface, which is the pressure-bearing surface of the force sensor. The circuit board is electrically connected to the sensitive element, wherein the elastomer includes an annular groove arranged around its side wall, and the annular groove is close to the first end. In the present application, the sensitive element is attached to the end face of the first end, and an annular groove is opened on the side wall close to the first end. When the force applied from the outside is transmitted from the force-bearing annular surface to the end face of the first end, a large deformation can be generated near the first end, so that the sensitive element can more directly receive the small deformation on the pressure-bearing surface and convert it into an electrical signal output. With such a configuration, the sensitivity of the sensor can be improved without thinning the elastomer structure.

Description

Technical Field

[0001] The present invention relates to the technical field of force sensors, and in particular to a force sensor. Background Art

[0002] A force sensor is a device used to measure the magnitude of force. It can convert the force applied to it into an electrical signal or other form of output corresponding to it. Force sensors are widely used in industry, research and science to measure and monitor various types of forces, such as pressure, compression, tension, torque, etc.

[0003] Force sensors are widely used. In some structures and devices that need to bear axial loads, force sensors are usually used to monitor the load-bearing structures or devices to ensure their normal operation. Specifically, in the automotive field, force sensors play a key role in automobile manufacturing and testing. They can be used to measure the output force of the engine, the pressure of the brake system, the load-bearing capacity of the suspension system, etc. By monitoring and analyzing these forces, vehicle performance, safety and efficiency can be improved (for example, by detecting the braking force during the clamping process of the brake caliper through a force sensor, the braking force can be optimized to provide optimal tire adhesion); in the industrial field, large machinery and equipment are required to handle and manipulate heavy objects. Force sensors will be installed in key parts of the machinery, such as the hook or lifting device of the crane, to measure and control the applied lifting or pressure.

[0004] Existing force sensors usually include an elastic body, which can produce a small deformation after being subjected to force. The sensitive element mounted on the elastic body can monitor this small deformation and convert it into an electrical signal output. However, existing force sensors have the problem of low sensitivity. If you want to improve the sensitivity, you usually have to reduce the overall thickness of the elastic body. However, reducing the overall thickness of the elastic body will reduce the structural strength of the force sensor, and it is impossible to ensure both structural strength and sensitivity. Summary of the invention

[0005] The embodiments of the present invention provide a force sensor, which can not only form a relatively large sensitivity output during the force measurement process, but also take into account the strength of the elastic body to a certain extent.

[0006] In order to solve the above technical problems, the embodiments of the present invention disclose the following technical solutions:

[0007] On the one hand, a force sensor is provided, comprising: an elastic body, a circuit board, a sensitive element and a support ring, wherein the elastic body comprises a first end and a second end opposite to each other, the support ring is sleeved on the elastic body, the sensitive element is attached to the end surface of the first end, the second end has a force-bearing annular surface, the support ring has a first annular surface, in the thickness direction of the elastic body, the force-bearing annular surface and the first annular surface are arranged opposite to each other, the force-bearing annular surface is a pressure-bearing surface of the force sensor, the first annular surface is a fixed constraint surface of the force sensor, and the circuit board is electrically connected to the sensitive element;

[0008] Wherein, the elastic body includes an annular groove arranged around its side wall, and the annular groove is close to the first end.

[0009] In addition to or as an alternative to one or more of the features disclosed above, the annular groove is in a continuous or discontinuous annular shape, and the annular groove is equidistant from the end surface of the first end.

[0010] In addition to or as an alternative to one or more of the features disclosed above, the sensitive element comprises a plurality of sensitive elements, and the plurality of sensitive elements are arranged at intervals around the center of the elastic body;

[0011] Wherein, two opposite sides of each of the sensitive elements include grooves opened along the thickness direction of the elastic body.

[0012] In addition to or as an alternative to one or more of the features disclosed above, the force-bearing annular surface protrudes from an end surface of the second end.

[0013] In addition to one or more of the features disclosed above, or as an alternative, an annular groove is further provided on the end surface of the second end of the elastomer, the annular groove is concentrically arranged with the force-bearing annular surface, and the inner diameter of the annular groove is larger than the inner diameter of the force-bearing annular surface.

[0014] In addition to one or more of the features disclosed above, or as an alternative, the present invention further includes a support member, wherein the support member includes a support plate, wherein the support plate is located between the circuit board and the end face of the first end, wherein the support member includes a lead window that passes through the thickness of the support member, wherein each of the sensitive elements has a corresponding lead window above, wherein the circuit board includes a lead connection position, wherein each of the lead windows has a corresponding lead connection position above, and the lead electrically connects the sensitive element and the circuit board through the lead window and the lead connection position.

[0015] In addition to or as an alternative to one or more of the features disclosed above, the support member further comprises an abutment ring, the abutment ring sleeve is arranged on the side wall of the elastic body close to the first end, the side wall of the elastic body close to the first end is convexly provided with a first abutment ring surface, one side of the abutment ring sleeve is fixedly connected to the support plate, and the other side abuts against the first abutment ring surface, so that a gap is left between the support plate and the first end;

[0016] Wherein, the abutment ring and the support plate are integrally formed.

[0017] In addition to one or more of the features disclosed above, or as an alternative, a connector is also included, the connector including a socket and a spring probe, in the thickness direction of the socket, the socket includes a plug end and a connecting end, the spring probe is fixedly connected to the socket and protrudes from the end surface of the plug end, and the connecting end is used to fix the socket.

[0018] In addition to one or more of the features disclosed above, or as an alternative, the circuit board includes a first limiting hole that passes through the thickness direction of the circuit board, the support plate includes a second limiting hole that passes through the thickness direction of the circuit board, the first limiting hole and the second limiting hole are connected, the connector also includes a foot, the foot is connected to the end face of the connecting end and protrudes from the end face of the connecting end, the foot is inserted between the first limiting hole and the second limiting hole, and a gap is left between the end face of the connecting end and the board surface of the circuit board.

[0019] In addition to one or more of the features disclosed above, or as an alternative, the aperture of the first limiting hole is larger than the aperture of the second limiting hole, the plate surface of the support plate is exposed in the first limiting hole, and a step surface is provided on the side of the foot away from the connecting end, and the step surface abuts against the exposed plate surface of the support plate.

[0020] In addition to or as an alternative to one or more of the features disclosed above, the foot base includes at least two, the first limiting holes correspond to the foot base one-to-one, and the second limiting holes correspond to the first limiting holes one-to-one.

[0021] In addition to or as an alternative to one or more of the features disclosed above, at least one of the first limiting holes is a polygonal hole, and at least one of the second limiting holes is a polygonal hole.

[0022] In addition to one or more of the features disclosed above, or as an alternative, the present invention further includes a sensor housing, wherein the sensor housing seals the circuit board, the support member and the first end, and a connecting groove is provided on a surface of the sensor housing away from the first end, wherein the connecting groove is for the connector to pass through, and the connector is exposed from the sensor housing.

[0023] In addition to or as an alternative to one or more of the features disclosed above, the support ring is nested with the sensor housing, and the inner wall of the support ring is in contact with the side wall of the sensor housing near the first end;

[0024] In the thickness direction of the elastomer, the support ring also includes a second annular surface, the second annular surface is arranged opposite to the first annular surface, and the side wall of the elastomer close to the first end is convexly provided with a second abutting annular surface, and the second annular surface abuts against the second abutting annular surface.

[0025] In addition to or as an alternative to one or more of the features disclosed above, the sensor further includes an anti-rotation positioning member, which is connected to the sensor housing and is located at a side of the sensor housing away from the first end.

[0026] In addition to or as an alternative to one or more of the features disclosed above, in the thickness direction of the elastomer, the groove pitch of the annular groove is less than or equal to a preset threshold.

[0027] In addition to or as an alternative to one or more of the features disclosed above, the groove is connected to or not connected to the annular groove.

[0028] One of the above technical solutions has the following advantages or beneficial effects: the sensitive element of the present application is attached to the end surface of the first end, the elastic body includes an annular groove arranged around its side wall, and the annular groove is close to the first end. When the force applied by the outside is transmitted from the force-bearing annular surface to the end surface of the first end, a large deformation can be generated near the first end, so that the sensitive element can more directly receive the small deformation on the pressure-bearing surface and convert it into an electrical signal output. In this way, the sensitivity of the sensor can be improved without thinning the elastic body structure. Further, the present application can limit the irregular distribution of stress by providing grooves on both sides of each sensitive element. Specifically, the grooves are provided on both sides of the sensitive element, so that the stress distribution can be constrained between the grooves and the sensitive element, so that the measured stress and the measured force basically maintain a strict corresponding relationship, improve the irregular distribution of stress, and improve the measurement accuracy of the force sensor. At the same time, the connector of the present application includes a socket and a spring probe, and the support plate and the sensor housing double limit the connector, which can not only ensure the position and reliability of the connector, but also improve the adaptability of the force sensor. Furthermore, the aperture of the first limiting hole is larger than the aperture of the second limiting hole, the board surface of the support plate is exposed in the first limiting hole, a step surface is provided on the side of the foot away from the connecting end, the step surface abuts against the exposed board surface of the support plate, and a gap is left between the end face of the connecting end and the board surface of the circuit board. When the force sensor is subjected to force, the connecting end of the socket will not be squeezed with the circuit board to damage the circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The technical solutions and other beneficial effects of the present invention will be made apparent by describing in detail the specific embodiments of the present invention in conjunction with the accompanying drawings.

[0030] Figure 1 The structure of a force sensor provided in accordance with an embodiment of the present application is shown in FIG. Figure 1 ;

[0031] Figure 2 The structure of a force sensor provided in accordance with an embodiment of the present application is shown in FIG. Figure 2 ;

[0032] Figure 3 The structure of a force sensor provided in accordance with an embodiment of the present application is shown in FIG. Figure 3 ;

[0033] Figure 4 yes Figure 3 A magnified view of point A.

[0034] Description of reference numerals:

[0035] 100, elastic body; 101, first end; 102, second end; 103, annular groove; 104, groove; 105, first abutting annular surface; 1051, positioning boss; 106, second abutting annular surface; 107, sealing groove; 108, force-bearing annular surface; 109, annular groove;

[0036] 200, circuit board; 201, lead connection position; 202, first positioning hole; 203, first limiting hole;

[0037] 300, sensitive components;

[0038] 400, support member; 401, support plate; 4011, lead window; 4012, second positioning hole; 4013, second limiting hole; 402, abutment ring; 4021, positioning notch;

[0039] 500, connector; 501, socket; 5011, connector end; 5012, connection end; 502, spring probe; 503, foot; 5031, stepped surface;

[0040] 600, sensor housing; 601, connection slot;

[0041] 700, anti-rotation positioning piece;

[0042] 800, assembly hole;

[0043] 900, sealing ring;

[0044] 1000, support ring; 1001, first ring surface; 1002, second ring surface. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and beneficial effects of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described in this specification are only for explaining the present invention, not for limiting the present invention.

[0046] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" refers to two or more, unless otherwise clearly and specifically defined.

[0047] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0049] The embodiment of the present invention discloses a force sensor, referring to Figure 1 , the force sensor includes: an elastic body 100, a circuit board 200, a sensitive element 300 and a support ring 1000. The elastic body 100 includes a first end 101 and a second end 102 opposite to each other. The sensitive element 300 is attached to the end surface of the first end 101, and the circuit board 200 is electrically connected to the sensitive element 300. The second end 102 has a force-bearing annular surface 108, and the support ring 1000 has a first annular surface 1001. In the thickness direction of the elastic body 100, the force-bearing annular surface 108 and the first annular surface 1001 are arranged opposite to each other. The force-bearing annular surface 108 is the pressure-bearing surface of the force sensor, and the first annular surface 1001 is the fixed constraint surface of the force sensor. The force-bearing annular surface 108 and the first annular surface 1001 together constitute the force model of the entire force sensor.

[0050] Specifically, the force-bearing annular surface 108 protrudes from the end surface of the second end 102. In practical applications, when the force-bearing annular surface 108 is subjected to force, the elastic body 100 is deformed, and the stress and strain generated by the deformation will be fed back to the sensitive element 300. In order to improve the sensitivity of the force sensor, specifically but not limitingly, the present application provides an elastic body 100 capable of improving the sensitivity of the force sensor, and the elastic body 100 includes an annular groove 103 arranged around its side wall, and the annular groove 103 is close to the first end 101. In this way, when the force applied by the outside is transmitted from the force-bearing annular surface 108 to the end surface of the first end 101, a large deformation can be generated near the first end 101, so that the sensitive element 300 can more directly receive the small deformation on the pressure-bearing surface and convert it into an electrical signal output. In addition, the existence of the annular groove 103 can make the side of the sensitive element 300 close to the edge of the elastic body 100 be subjected to tension, and the side close to the center of the elastic body 100 be subjected to pressure, so as to increase the sensitivity of the force sensor. With such a configuration, the sensitivity of the sensor can be improved without thinning the elastic body 100 structure.

[0051] In order to further improve the sensitivity of the force sensor, refer to Figure 3 In some embodiments, an annular groove 109 is further provided on the end surface of the second end 102 of the elastomer 100 . The annular groove 109 is concentrically arranged with the force-bearing annular surface 108 , and the inner diameter of the annular groove 109 is larger than the inner diameter of the force-bearing annular surface 108 .

[0052] In some embodiments, reference Figure 1 , the annular groove 103 is a continuous annular shape, and the annular groove 103 is equidistant from the end surface of the first end 101. In some embodiments, referring to Figure 2 The annular groove 103 includes a plurality of annular grooves 103 which are arranged at intervals along the circumference of the elastic body 100 and surround the elastic body 100 in a circle. The distances between all the annular grooves 103 and the end surface of the first end 101 are equal.

[0053] Furthermore, in some embodiments, the sensitive element 300 may include a plurality of sensitive elements 300, and the plurality of sensitive elements 300 are arranged at intervals around the center of the elastic body 100. Figure 2 In this application, four sensitive elements 300 are set as an example. The four sensitive elements 300 are arranged around the center of the elastomer 100 at intervals, and four annular grooves 103 are also set accordingly. The annular grooves 103 correspond to the sensitive elements 300 one by one, and the annular grooves 103 are located below the corresponding sensitive elements 300.

[0054] In order to improve the sensitivity of the force sensor without affecting the structural strength of the elastic body 100, the groove pitch of the annular groove 103 is less than or equal to the preset threshold in the thickness direction of the elastic body 100. The preset threshold is set based on the thickness of the elastic body 100. In some embodiments, the preset threshold is 0.15 times the thickness of the elastic body 100.

[0055] Continue to refer to Figure 1 and Figure 2 In order to further improve the sensitivity and measurement accuracy of the force sensor, the present application specifically but not restrictively proposes an elastomer 100, in the thickness direction of the elastomer 100, the elastomer 100 is provided with a groove 104 on the end surface of the first end 101, and each of the two opposite sides of the sensitive element 300 is provided with the groove 104. Specifically, the grooves 104 are provided on the two opposite sides of the sensitive element 300, so that the stress distribution can be constrained between the grooves 104 and the sensitive element 300, so that the measured stress and the measured force basically maintain a strict corresponding relationship, improve the situation of irregular stress distribution, and improve the measurement accuracy of the force sensor. In some embodiments, the groove 104 and the annular groove 103 are not connected. In some embodiments, the groove 104 and the annular groove 103 can be connected.

[0056] It should be noted that the sensitive element 300 may be different components, and in the embodiment of the present application, the sensitive element 300 is a resistance strain gauge, and the resistance strain gauge is mounted on the end surface of the first end 101 by glass micro-melting process.

[0057] Furthermore, the elastic body 100 is usually made of metal. The direct contact between the metal elastic body 100 and the circuit board 200 may cause a short circuit, thereby affecting the accuracy and stability of the force sensor. At the same time, in order to avoid electromagnetic interference generated by the electronic components on the circuit board 200 and affecting the performance of the sensor, in some embodiments, the reference Figure 2 and Figure 3The force sensor also includes a support member 400, and the support member 400 includes a support plate 401, and the support plate 401 is located between the circuit board 200 and the end surface of the first end 101. In different embodiments, the support plate 401 can be fixedly connected to the circuit board 200 in different ways. The present application specifically but not restrictively proposes a connection method, in which the circuit board 200 is fixedly connected to the support plate 401 by glue, and the circuit board 200 is not limited to a hard board made of FR4 material, but can also be a corresponding soft board, and the surface of the circuit board 200 used for connecting with the support plate 401 can also be provided with adhesive backing, and connected to the support plate 401 by the adhesive backing.

[0058] Specifically, in the embodiment provided in the present application, the shape and size of the support plate 401 are adapted to the end surface of the first end 101, and the shape and size of the circuit board 200 are adapted to the support plate 401. The circuit board 200 is usually mounted with chips and components (not shown in the figure). In different embodiments, the sensitive element 300 mounted on the end surface of the first end 101 can be electrically connected to the chips and components on the circuit board 200 in different ways. For example, continue to refer to Figure 1 and Figure 2 The embodiment of the present application provides an electrical connection method, wherein the support plate 401 includes lead windows 4011 that penetrate the thickness of the support plate 401, the number of lead windows 4011 is equal to the number of sensitive elements 300, the lead windows 4011 correspond to the sensitive elements 300 one by one, and the lead windows 4011 are located above the corresponding sensitive elements 300. The circuit board 200 includes lead connection positions 201, the number of lead connection positions 201 is equal to the number of lead windows 4011, the lead connection positions 201 correspond to the lead windows 4011 one by one, and the lead connection positions 201 are located above the corresponding lead windows 4011. When the circuit board 200 and the sensitive element 300 are electrically connected, the lead can be bonded to connect the sensitive element 300 and the circuit board 200 through the lead windows 4011 and the lead connection positions 201, so as to transmit the electrical signal transmitted by the sensitive element 300 to the chip or component on the circuit board 200. As mentioned above, the embodiment disclosed in the present application is provided with four sensitive elements 300, and the sensitive elements 300 use resistance strain gauges. In the embodiment disclosed in the present application, the four sensitive elements 300 form a Wheatstone bridge, which can output a differential signal after being connected to the circuit board 200. After the differential signal is input into the circuit board 200, it can be amplified accordingly by the circuit in the circuit board 200. The circuit in the circuit board 200 can also convert the amplified signal into analog or digital form for further processing or analysis.

[0059] In order to enable the circuit board 200 and the support plate 401 to be accurately matched and assembled, in some embodiments, continue to refer to Figure 1 and Figure 2The circuit board 200 includes a first positioning hole 202 that penetrates the thickness of the circuit board 200, and the support plate 401 includes a second positioning hole 4012 that penetrates the thickness of the circuit board 200. The first positioning hole 202 and the second positioning hole 4012 are coaxial. During assembly, positioning members (not shown in the figure) are inserted into the first positioning hole 202 and the second positioning hole 4012. In order to facilitate the assembly of the support member 400 and the elastic body 100, in some embodiments, continue to refer to Figure 1 and Figure 2 The support member 400 further includes an abutment ring 402, which is sleeved on the side wall of the elastic body 100 near the first end 101. The side wall of the elastic body 100 near the first end 101 is convexly provided with a first abutment ring surface 105. One side of the abutment ring 402 is fixedly connected to the support plate 401, and the other side abuts against the first abutment ring surface 105, so that a gap is left between the support plate 401 and the first end 101. Moreover, in some embodiments, the abutment ring 402 is integrally formed with the support plate 401. It should be noted that in the embodiments disclosed in the present application, the side of the abutment ring 402 used to abut the first abutment ring surface 105 can be connected to the first abutment ring surface 105 by welding, so as to encapsulate the support member 400 and the elastic body 100. Furthermore, in order to facilitate the positioning and assembly of the support plate 401 and the first end 101, a positioning notch 4021 is provided on one side of the abutment ring 402 abutting against the first abutment ring surface 105, and a positioning boss 1051 is convexly provided on the first abutment ring surface 105. The positioning notch 4021 is matched with the positioning boss 1051. During assembly, the positioning assembly of the support member 400 and the elastomer 100 is completed by snapping the positioning notch 4021 and the positioning boss 1051.

[0060] In practical applications, force sensors are usually connected to other devices. In order to facilitate the installation and removal of force sensors, force sensors usually include a connector 500. Existing force sensors usually use matching male and female connectors to connect sensor signals, which has a low degree of adaptability. In order to improve the adaptability of force sensors, this application specifically but not restrictively proposes a force sensor, referring to Figure 1 and Figure 2, which includes a connector 500, the connector 500 includes a socket 501 and a spring probe 502. In the thickness direction of the socket 501, the socket 501 includes a plug end 5011 and a connection end 5012. The spring probe 502 is fixedly connected to the socket 501 and protrudes from the end surface of the plug end 5011. The connection end 5012 is used to fix the socket 501. The connector 500 used in the present application allows the spring probe 502 to automatically adjust during the insertion and connection process, and can adapt to a larger tolerance range. Even if there is a slight alignment error between the connector 500 and the corresponding connection point, the spring probe 502 can compensate for this error through its elasticity to ensure a reliable connection. It is worth mentioning that in the embodiment disclosed in the present application, three spring probes 502 are provided. In actual applications, the number of spring probes 502 can be other numbers.

[0061] Furthermore, in different embodiments, the connector 500 is assembled in different ways. Specifically but not limitingly, the present application embodiment provides an assembly structure, referring to Figure 2 and Figure 3 The circuit board 200 includes a first limiting hole 203 that passes through the thickness direction of the circuit board 200, and the support plate 401 includes a second limiting hole 4013 that passes through the thickness direction of the circuit board 200. The first limiting hole 203 and the second limiting hole 4013 are connected. The connector 500 also includes a foot 503, which is connected to the end face of the connection end 5012 and protrudes from the end face of the connection end 5012. The foot 503 is inserted between the first limiting hole 203 and the second limiting hole 4013, and the side of the foot 503 away from the connection end 5012 abuts against the end face of the first end 101, and a gap is left between the end face of the connection end 5012 and the board surface of the circuit board 200. With such a configuration, when the force sensor is subjected to force, the connection end 5012 of the socket 501 will not be squeezed with the circuit board 200, thereby avoiding damage to the circuit board 200. In order to further protect the circuit board 200, in some embodiments, the aperture of the first limiting hole 203 is larger than the aperture of the second limiting hole 4013, the board surface of the support plate 401 is exposed in the first limiting hole 203, and a stepped surface 5031 is provided on the side of the foot 503 away from the connection end 5012, and the stepped surface 5031 abuts against the exposed board surface of the support plate 401. In this way, a gap is left between the end surface of the connection end 5012 and the board surface of the circuit board 200, and a gap is left between the support plate 401 and the first end 101. When the force sensor is subjected to force, the circuit board 200 will still not be squeezed, the stepped surface 5031 will be squeezed with the support plate 401, and the foot 503 will not be squeezed with the end surface of the first end 101, so as to avoid introducing squeezing stress to the end surface of the first end 101 and affecting the measurement accuracy of the force sensor.

[0062] Continue to refer to Figure 2In different embodiments, the foot base 503 can be set to be multiple, the number of the first limiting holes 203 is set based on the number of the foot bases 503, the number of the second limiting holes 4013 is also set based on the number of the foot bases 503, and the first limiting holes 203 correspond to the foot bases 503 one by one, and the second limiting holes 4013 correspond to the first limiting holes 203 one by one. The first limiting holes 203 can be square, circular, or other polygonal holes, and the second limiting holes 4013 can be square, circular, or other polygonal holes. In order to ensure that the connector 500 is correctly assembled, in some embodiments, at least one first limiting hole 203 is a polygonal hole, and at least one second limiting hole 4013 is a polygonal hole. Specifically, in the technical solution disclosed in the present application, three foot seats 503 are provided, one of which is a rectangular parallelepiped, and two of which are cylindrical. The first limiting hole 203 and the second limiting hole 4013 corresponding to the rectangular parallelepiped foot seat 503 are both square holes, and the first limiting hole 203 and the second limiting hole 4013 corresponding to the cylindrical foot seat 503 are both circular holes. In this way, the docking plug 500 is lowered by the step surface 5031 abutting against the support plate 401, and the docking plug 500 is circumferentially limited by the first limiting hole 203 and the second limiting hole 4013.

[0063] In order to better package the force sensor, in some embodiments, the force sensor further includes a sensor housing 600. Figure 2 and Figure 3 The sensor housing 600 seals the circuit board 200, the support member 400 and the first end 101. A connection groove 601 is provided on the surface of the sensor housing 600 away from the first end 101. The connection groove 601 is for the plug end 5011 to pass through. The plug end 5011 is exposed from the sensor housing 600. With such a configuration, the upper limit of the docking line can be set, thereby realizing the dual positioning of the docking plug 500. Furthermore, an anti-rotation positioning member 700 is also provided on the sensor housing 600. The anti-rotation positioning member 700 protrudes from the side of the sensor housing 600 away from the circuit board 200. The anti-rotation positioning member 700 can prevent the force sensor from rotating to a certain extent when assembled with other equipment. It should be noted that the anti-rotation positioning member 700 can be a cylinder, a rhombus, or other polygonal bodies. Moreover, when the sensor housing 600 seals the elastomer 100, a second abutment ring surface 106 is protruded from the side wall of the elastomer 100 close to the first end 101, and the side of the sensor housing 600 close to the elastomer 100 abuts against the second abutment ring surface 106, and can be fixedly connected by welding to further encapsulate the force sensor.

[0064] In some embodiments, the support ring 1000 is nested with the sensor housing 600, and the inner wall of the support ring 1000 is in contact with the side wall of the sensor housing 600 near the first end 101. In the thickness direction of the elastic body 100, the support ring 1000 also includes a second annular surface 1002. The second annular surface 1002 is arranged opposite to the first annular surface 1001. Figure 3 The side wall of the elastic body 100 close to the first end 101 is convexly provided with a second abutting annular surface 106, and the second annular surface 1002 is also abutted against the second abutting annular surface 106. It should be noted that the second annular surface 1002 can also be fixedly connected to the second abutting annular surface 106 by welding.

[0065] Reference Figure 2 and Figure 3 In some embodiments, the elastomer 100 includes an assembly hole 800 that penetrates through its thickness, and the assembly hole 800 is located at the center of the elastomer 100. Correspondingly, the circuit board 200 and the support plate 401 are both provided with an assembly hole 800. When the circuit board 200, the support member 400 and the first end 101 are packaged, the hole wall of the assembly hole 800 formed by the elastomer 100, the circuit board 200 and the support plate 401 are also packaged, and the hole wall at the elastomer 100 includes a sealing groove 107 opened along the circumference of the assembly hole 800, and a sealing ring 900 is embedded in the sealing groove 107. The sensor housing 600 abuts against the sealing ring 900 to form a radial seal for the force sensor. Prevent lubricants such as butter from penetrating into the force sensor when the force sensor is assembled with other equipment.

[0066] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A force sensor, characterized in that: include: An elastic body (100), a circuit board (200), a sensitive element (300), and a support ring (1000), wherein the elastic body (100) comprises a first end (101) and a second end (102) which are opposite to each other, the support ring (1000) is sleeved on the elastic body (100), the sensitive element (300) is attached to the end surface of the first end (101), the second end (102) has a force-bearing annular surface (108), the support ring (1000) has a first annular surface (1001), in the thickness direction of the elastic body (100), the force-bearing annular surface (108) and the first annular surface (1001) are arranged opposite to each other, the force-bearing annular surface (108) is the pressure-bearing surface of the force sensor, the first annular surface (1001) is the fixed constraint surface of the force sensor, and the circuit board (200) is electrically connected to the sensitive element (300); The elastic body (100) comprises at least one annular groove (103) arranged around its side wall, the annular groove (103) is close to the first end (101), and the inner diameter of the annular groove (103) is smaller than the outer diameter of the first end (101). The annular groove (103) is in the form of a continuous or discontinuous annular shape, and the annular groove (103) is equidistant from the end face of the first end (101). When a force applied from the outside is transmitted from the force-bearing annular face (108) to the end face of the first end (101), the presence of the annular groove (103) causes a side of the sensitive element (300) close to the edge of the elastic body (100) to be subjected to tension, and a side close to the center of the elastic body (100) to be subjected to pressure.

2. The force sensor according to claim 1, characterized in that: The sensitive element (300) comprises a plurality of sensitive elements (300), and the plurality of sensitive elements (300) are arranged at intervals around the center of the elastic body (100); Wherein, two opposite sides of each of the sensitive elements (300) include grooves (104) opened along the thickness direction of the elastic body (100).

3. The force sensor according to claim 1, characterized in that: The force-bearing annular surface (108) protrudes from the end surface of the second end (102).

4. The force sensor according to claim 3, characterized in that: An annular groove (109) is also provided on the end surface of the second end (102) of the elastic body (100), the annular groove (109) is arranged concentrically with the force-bearing annular surface (108), and the inner diameter of the annular groove (109) is larger than the inner diameter of the force-bearing annular surface (108).

5. The force sensor according to claim 2, characterized in that: The invention also comprises a support member (400), wherein the support member (400) comprises a support plate (401), wherein the support plate (401) is located between the circuit board (200) and the end surface of the first end (101), wherein the support member (400) comprises a lead window (4011) penetrating the thickness of the support member (400), wherein each of the sensitive elements (300) has a corresponding lead window (4011) above, and wherein the circuit board (200) comprises a lead connection position (201), wherein each of the lead windows (4011) has a corresponding lead connection position (201) above, and the lead electrically connects the sensitive element (300) and the circuit board (200) through the lead window (4011) and the lead connection position (201).

6. The force sensor according to claim 5, wherein the support member (400) further comprises an abutment ring (402), wherein the abutment ring (402) is sleeved on a side wall of the elastic body (100) close to the first end (101), and a first abutment ring surface (105) is convexly provided on the side wall of the elastic body (100) close to the first end (101), and one side of the abutment ring (402) is fixedly connected to the support plate (401), and the other side abuts against the first abutment ring surface (105), so that a gap is left between the support plate (401) and the first end (101); in, The abutment ring (402) and the support plate (401) are integrally formed.

7. The force sensor according to claim 5, characterized in that: The invention also comprises a connector (500), wherein the connector (500) comprises a connector socket (501) and a spring probe (502); in the thickness direction of the connector socket (501), the connector socket (501) comprises a connector end (5011) and a connection end (5012); the spring probe (502) is fixedly connected to the connector socket (501) and protrudes from the end surface of the connector end (5011); and the connection end (5012) is used to fix the connector socket (501).

8. The force sensor according to claim 7, characterized in that: The circuit board (200) comprises a first limiting hole (203) extending through the thickness direction of the circuit board, the support plate (401) comprises a second limiting hole (4013) extending through the thickness direction of the support plate, the first limiting hole (203) and the second limiting hole (4013) being connected to each other, the connector (500) further comprises a foot seat (503), the foot seat (503) being connected to the end face of the connection end (5012) and protruding from the end face of the connection end (5012), the foot seat (503) being inserted between the first limiting hole (203) and the second limiting hole (4013), and a gap being left between the end face of the connection end (5012) and the board surface of the circuit board (200).

9. The force sensor according to claim 8, characterized in that: The aperture of the first limiting hole (203) is larger than the aperture of the second limiting hole (4013); the plate surface of the support plate (401) is exposed in the first limiting hole (203); a stepped surface (5031) is provided on a side of the foot seat (503) away from the connecting end (5012); and the stepped surface (5031) abuts against the exposed plate surface of the support plate (401).

10. The force sensor according to claim 8, characterized in that: The foot base (503) includes at least two, the first limiting holes (203) and the foot base (503) correspond one to one, and the second limiting holes (4013) and the first limiting holes (203) correspond one to one.

11. The force sensor according to claim 9, characterized in that: At least one of the first limiting holes (203) is a polygonal hole, and at least one of the second limiting holes (4013) is a polygonal hole.

12. The force sensor according to claim 7, characterized in that: It also includes a sensor housing (600), wherein the sensor housing (600) seals the circuit board (200), the support member (400) and the first end (101), and a connection groove (601) is provided on a surface of the sensor housing (600) away from the first end (101), and the connection groove (601) is provided for the connector end (5011) to pass through so that the connector end (5011) is exposed from the sensor housing (600).

13. The force sensor according to claim 12, characterized in that: The support ring (1000) and the sensor housing (600) are nested, and the inner wall of the support ring (1000) is in contact with the side wall of the sensor housing (600) close to the first end (101); In the thickness direction of the elastomer (100), the support ring (1000) further includes a second annular surface (1002), the second annular surface (1002) being arranged opposite to the first annular surface (1001), and a second abutting annular surface (106) is convexly provided on the side wall of the elastomer (100) close to the first end (101), and the second annular surface (1002) abuts against the second abutting annular surface (106).

14. The force sensor according to claim 12, characterized in that: It also includes an anti-rotation positioning member (700), which is connected to the sensor housing (600) and is located on a side of the sensor housing (600) away from the first end (101).

15. The force sensor according to claim 1, characterized in that: In the thickness direction of the elastic body (100), the groove pitch of the annular groove (103) is less than or equal to a preset threshold.

16. The force sensor according to claim 2, characterized in that: The groove (104) is connected to or not connected to the annular groove (103).

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