High-precision long-life tension and pressure sensor

Abstract

The utility model discloses a tension and pressure sensor with high precision and long service life, which comprises an elastic body, the elastic body is of a cylindrical structure with a closed top end, the bottom end of the elastic body is provided with an opening, a resistance-type strain gauge can be arranged in the elastic body through the opening, and the resistance-type strain gauge is arranged in the elastic body and clings to the top wall of the elastic body. According to the utility model, the first sealing structure is arranged at the joint of the cover plate and the opening at the bottom end of the elastic body, the second sealing structure is arranged between the waterproof joint and the via hole, and the third sealing structure is arranged between the wire hole of the end cover and the wire, so that the interior of the elastic body can be kept closed through the three sealing structures; the resistance-type strain gauges installed in the elastic body are not prone to being affected with damp and not prone to being corroded and rusted, the strain gauges can be kept clean all the time, the high-precision measurement standard can still be kept after long-term use, and the service life of the strain gauges is longer.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a high-precision and long-life tension and pressure sensor. Background Art

[0002] Tension and pressure sensors are sensors that can measure tensile or compressive forces. They usually work based on the principle of resistive strain and are widely used in many fields such as industry, automobiles, medical care, aerospace, etc.

[0003] The current tension and pressure sensors have complex structural designs and high processing costs, which limit their applications in certain fields. At the same time, the interior of the sensor is connected to the external environment, and the sensor lacks a sealing structure. The interior of the sensor is easily damaged by moisture, affecting the measurement accuracy and service life. Utility Model Content

[0004] The utility model aims to provide a high-precision and long-life tension and pressure sensor to solve the problems raised in the above-mentioned background technology.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A high-precision and long-life tension and pressure sensor, comprising

[0007] An elastic body, wherein the elastic body is a cylindrical structure with a closed top and an opening at the bottom, through which a resistance strain gauge can be installed in the elastic body;

[0008] A resistance strain gauge, which is installed in the elastic body and is arranged close to the top wall of the elastic body;

[0009] A plurality of sealing structures, wherein the plurality of sealing structures are used to seal the elastic body and protect the resistance strain gauge installed in the elastic body;

[0010] A connecting member is used to connect the elastic body with an external force-applying unit, and the connecting member includes an upper connecting member and a lower connecting member.

[0011] As a further solution of the utility model: a plurality of lower positioning pin holes and a plurality of lower connecting screw holes are provided around the outer edge of the bottom end of the elastomer, and the plurality of lower positioning pin holes and the plurality of lower connecting screw holes are used together to constitute a lower connecting piece; a connecting plate is fixed to the top of the elastomer, an upper positioning pin hole is provided at the center of the connecting plate, and upper connecting screw holes are provided at the four corners of the connecting plate; the connecting plate, the upper positioning pin holes and the upper connecting screw holes are used together to constitute an upper connecting piece, the elastomer is connected to the force applying unit on one side of the outside through the upper connecting piece, and the elastomer is connected to the force applying unit on the other side of the outside through the lower connecting piece.

[0012] As a further solution of the utility model: a cavity is provided inside the elastomer, a mounting platform is provided on the top of the cavity, a plurality of resistive strain gauges are evenly provided in the cavity around the mounting platform, the plurality of resistive strain gauges are arranged close to the top wall of the cavity, the resistive strain gauges deform synchronously with the elastomer, and the resistive strain gauges are connected to an external measurement circuit through a wire.

[0013] As a further solution of the utility model: an annular recess is provided at the outer edge of the opening at the bottom end of the elastomer, and the inner wall of the elastomer extends horizontally inward corresponding to the upper end of the recess to form a horizontal extension portion, the horizontal extension portion is an annular structure, and its annular inner edge extends vertically downward to form a vertical extension portion, the vertical extension portion is an annular plate structure, and a slot is formed between the vertical extension portion and the side wall of the elastomer, a first annular groove is provided on the outer circumference of the vertical extension portion, a first sealing ring is fixed in the first annular groove, and the first sealing ring expands to the outside of the first annular groove.

[0014] As a further solution of the utility model: the bottom end of the elastomer is provided with an opening and a cover plate is fixed in the opening by a plurality of fastening bolts, the cover plate is arranged in the concave edge of the opening at the bottom end of the elastomer, and an annular step is integrally formed on the top of the cover plate corresponding to one side of the slot, the annular step is inserted into the slot, and the annular step covers the vertical extension portion, the inner wall of the annular step is interference fit with the first sealing ring on the outer periphery of the vertical extension portion, the annular step, the first sealing ring and the slot are used in combination to form a first sealing structure between the opening at the bottom end of the elastomer and the cover plate.

[0015] As a further solution of the utility model: a waterproof joint is provided on one side of the elastomer, and a through hole is provided on the inner wall of the elastomer on one side corresponding to the waterproof joint, and an internal thread is provided in the through hole. The waterproof joint is a hollow tubular structure and an external thread is provided at one end corresponding to the through hole, and the external thread is used in conjunction with the internal thread to tighten and fix the waterproof joint, and a second annular groove is provided at the outer end of the waterproof joint corresponding to the external thread, and a second sealing ring is fixed in the second annular groove, the second sealing ring expands outward and has an interference fit with the through hole, so as to seal the through hole and block the gap at the threaded connection between the waterproof joint and the through hole, and the second sealing ring is used in conjunction with the through hole to form a second sealing structure between the elastomer and the waterproof joint.

[0016] As a further solution of the utility model: an end cap is integrally formed at one end of the waterproof connector away from the through hole, a plurality of wire holes are opened on the end cap, and the wires are inserted into the plurality of wire holes, one end of the wire is connected to the resistive strain gauge and the other end is connected to an external measurement circuit, a third sealing ring is fixed at the gap between the wire hole and the wire, the third sealing ring is used to block the gap left when the wire passes through the end cap and keep the end cap sealed, the third sealing ring is used in conjunction with the wire hole to form a third sealing structure at the end cap.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1. In the utility model, a first sealing structure is provided at the connection between the cover plate and the bottom opening of the elastic body, a second sealing structure is provided between the waterproof joint and the through hole, and a third sealing structure is provided between the wire hole of the end cover and the wire. By providing these three sealing structures, the inside of the elastic body can be kept airtight, and the resistance strain gauge installed inside the elastic body is not easy to be affected by moisture, corrosion and rust. The strain gauge can be kept clean all the time, and can still maintain a high-precision measurement standard under long-term use, and the service life of the strain gauge is longer;

[0019] 2. In the utility model, the resistive strain gauge is arranged close to the top wall of the elastic body. When the elastic body is deformed, the resistive strain gauge close to the elastic body will be driven to deform synchronously, and the resistance coefficient of the resistive strain gauge will change. The resistive strain gauge is connected to an external measuring circuit. When the resistance of the strain gauge changes, the voltage of the measuring circuit will change synchronously. The pressure value is calculated according to the voltage change. The device has a simple structure, is easy to manufacture, and is simple and efficient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for describing the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 This is a schematic structural diagram of the utility model from the first perspective.

[0022] Figure 2 This is a schematic diagram of the structure of the utility model from a second viewing angle.

[0023] Figure 3 It is a schematic diagram of the connection structure between the elastic body and the waterproof joint in the utility model.

[0024] Figure 4This is a first viewing angle diagram of the internal structure of the elastic body in the utility model.

[0025] Figure 5 This is a second viewing angle diagram of the internal structure of the elastic body in the utility model.

[0026] Notes on figure marks: 1-elastic body, 11-lower positioning pin hole, 12-lower connecting screw hole, 13-through hole, 14-internal thread, 15-first sealing ring, 16-cavity, 17-recess, 18-horizontal extension portion, 19-vertical extension portion, 110-first annular groove, 111-slot, 2-connecting plate, 21-upper connecting screw hole, 22-upper positioning pin hole, 3-waterproof connector, 31-second sealing ring, 32-external thread, 33-end cover, 34-conducting wire, 35-second annular groove, 36-wire hole, 37-third sealing ring, 4-cover plate, 41-fastening bolt, 42-annular step, 5-mounting table, 6-resistance strain gauge. DETAILED DESCRIPTION

[0027] The following embodiments will be combined with the accompanying drawings to describe the utility model in detail. In the drawings or descriptions, similar or identical parts use the same reference numerals, and in actual applications, the shape, thickness or height of each component can be enlarged or reduced. The various embodiments listed in the utility model are only used to illustrate the utility model, and are not used to limit the scope of the utility model. Any obvious modifications or changes made to the utility model do not depart from the spirit and scope of the utility model.

[0028] Example 1

[0029] See also Figures 1-2 In the embodiment of the utility model, a high-precision and long-life tension and pressure sensor includes an elastic body 1, which will deform under the action of pressure. The elastic body 1 is a cylindrical structure with a closed top, and a plurality of lower positioning pin holes 11 and a plurality of lower connecting screw holes 12 are opened around the outer edge of the bottom end of the elastic body 1. The plurality of lower positioning pin holes 11 and the plurality of lower connecting screw holes 12 are used together to form a lower connecting member;

[0030] A connecting plate 2 is fixed to the top of the elastomer 1, an upper positioning pin hole 22 is opened at the center of the connecting plate 2, and upper connecting screw holes 21 are opened at the four corners of the connecting plate 2. The connecting plate is used in conjunction with the positioning pin holes and connecting screw holes opened on the connecting plate to constitute an upper connecting member. The elastomer 1 is connected to the force-applying unit on one side of the outside through the connecting plate 2, and the elastomer 1 is connected to the force-applying unit on the other side of the outside through the lower positioning pin hole 11 and the lower connecting screw hole 12 at its bottom end. A waterproof joint 3 is provided on one side of the elastomer 1, an opening is provided at the bottom end of the elastomer 1, and a cover plate 4 is fixed in the opening. The cover plate 4 is connected and fixed to the elastomer 1 by multiple fastening bolts 41.

[0031] See also Figures 4-5The elastic body 1 is provided with a cavity 16 inside, a mounting platform 5 is provided on the top of the cavity 16, and a plurality of resistance strain gauges 6 are evenly provided around the mounting platform 5 in the cavity 16, and the plurality of resistance strain gauges 6 are arranged close to the top wall of the cavity 16. When the elastic body is deformed, the resistance strain gauge close to the elastic body will be driven to deform synchronously, and the resistance coefficient of the resistance strain gauge will be changed. The resistance strain gauge is connected to an external measurement circuit. When the resistance of the strain gauge changes, the voltage of the measurement circuit will change synchronously. The pressure value is calculated according to the voltage change. Measuring pressure by resistance strain gauge belongs to the prior art. The resistance strain gauge in this embodiment can be used by using the existing device and the existing technology. The detailed measurement and calculation method will not be repeated here.

[0032] An annular concave edge 17 is provided at the outer edge of the bottom opening of the elastic body 1, and the upper end of the inner wall of the elastic body 1 corresponding to the concave edge 17 extends horizontally inward to form a horizontal extension portion 18, and the horizontal extension portion 18 is annular in structure, and its annular inner edge extends vertically downward to form a vertical extension portion 19, and the vertical extension portion 19 is an annular plate structure, and a slot 111 is formed between the vertical extension portion 19 and the side wall of the elastic body 1, and a first annular groove 110 is provided on the outer circumference of the vertical extension portion 19, and a first sealing ring 15 is fixed in the first annular groove 110, and the first sealing ring 15 expands to the first annular groove 110. The cover plate 4 is fixed in the concave edge 17 of the opening at the bottom end of the elastomer 1, and an annular step 42 is integrally formed on one side of the top of the cover plate 4 corresponding to the slot 111. The annular step 42 is inserted into the slot 111, and the annular step 42 covers the vertical extension portion 19. The inner wall of the annular step 42 is interference fit with the first sealing ring 15 on the outer periphery of the vertical extension portion 19. In this embodiment, the annular step 42, the horizontal extension portion 18, the vertical extension portion 19, the first sealing ring 15 and the slot 111 are used in combination to form a first sealing structure in the opening at the bottom end of the elastomer to seal the opening at the bottom end of the elastomer.

[0033] Example 2

[0034] See also Figure 3 On the basis of Example 1, a through hole 13 is provided on the inner wall of one side of the elastic body 1 corresponding to the waterproof joint 3, and an internal thread 14 is provided in the through hole 13. The waterproof joint 3 is a hollow tubular structure and an external thread 32 is provided at one end corresponding to the through hole 13. The external thread 32 is used in conjunction with the internal thread 14 to tighten and fix the waterproof joint 3;

[0035] A second annular groove 35 is provided at the outer end of the waterproof connector 3 corresponding to the external thread 32, and a second sealing ring 31 is fixed in the second annular groove 35. The second sealing ring 31 expands outward and is interference-fitted with the through hole 13, and is used to seal the through hole 13 and block the gap at the connection between the waterproof connector and the through hole thread. An end of the waterproof connector 3 away from the through hole 13 is integrally formed with an end cap 33, and a plurality of wire holes 36 are provided on the end cap 33, and wires 34 are inserted into the plurality of wire holes 36. One end of the wire 34 is connected to the resistance strain gauge 6 and the other end thereof is connected to the external measurement circuit. A third sealing ring 37 is fixed at the gap where the wire hole 36 and the wire 34 are connected.

[0036] In this embodiment, a second sealing ring is arranged between the joint and the through hole, so that the gap of the threaded connection can be blocked. The second sealing ring and the through hole have an interference fit to form a second sealing structure of the device. At the same time, when the wire passes through the joint, a third sealing ring is arranged in the end cover of the joint to block the gap left when the wire passes through the end cover. The third sealing ring and the end cover are used in conjunction to form the third sealing structure of the device. Through the three sealing structures, the interior of the elastomer is kept airtight, and the resistive strain gauge installed inside the elastomer is not easily affected by moisture, corrosion, and rust. The strain gauge remains clean and can still maintain a high-precision measurement standard during long-term use. The strain gauge has a longer service life. The device has a simple structure, is easy to manufacture, and has a good use effect.

[0037] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0038] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A high-precision and long-life tension and pressure sensor, characterized in that: include An elastic body, wherein the elastic body is a cylindrical structure with a closed top and an opening at the bottom, through which a resistance strain gauge can be installed in the elastic body; A resistance strain gauge, which is installed in the elastic body and is arranged close to the top wall of the elastic body; A plurality of sealing structures, wherein the plurality of sealing structures are used to seal the elastic body and protect the resistance strain gauge installed in the elastic body; A connecting member is used to connect the elastic body with an external force-applying unit, and the connecting member includes an upper connecting member and a lower connecting member.

2. The high-precision and long-life tension and pressure sensor according to claim 1, characterized in that: A plurality of lower positioning pin holes and a plurality of lower connecting screw holes are provided around the outer edge of the bottom end of the elastomer, and the plurality of lower positioning pin holes and the plurality of lower connecting screw holes are used together to constitute a lower connecting piece, a connecting plate is fixed to the top of the elastomer, an upper positioning pin hole is provided at the center of the connecting plate, and upper connecting screw holes are provided at the four corners of the connecting plate, the connecting plate, the upper positioning pin holes and the upper connecting screw holes are used together to constitute an upper connecting piece, the elastomer is connected to the force applying unit on one side of the outside through the upper connecting piece, and the elastomer is connected to the force applying unit on the other side of the outside through the lower connecting piece.

3. The high-precision and long-life tension and pressure sensor according to claim 1, characterized in that: A cavity is provided inside the elastomer, a mounting platform is provided on the top of the cavity, a plurality of resistive strain gauges are evenly provided in the cavity around the mounting platform, the plurality of resistive strain gauges are arranged close to the top wall of the cavity, the resistive strain gauges deform synchronously with the elastomer, and the resistive strain gauges are connected to an external measurement circuit through a wire.

4. The high-precision and long-life tension and pressure sensor according to claim 3, characterized in that: An annular recess is provided at the outer edge of the opening at the bottom end of the elastomer, and the inner wall of the elastomer extends horizontally inward corresponding to the upper end of the recess to form a horizontal extension portion, the horizontal extension portion is annular in structure, and its annular inner edge extends vertically downward to form a vertical extension portion, the vertical extension portion is annular in structure, and a slot is formed between the vertical extension portion and the side wall of the elastomer, a first annular groove is provided on the outer circumference of the vertical extension portion, a first sealing ring is fixed in the first annular groove, and the first sealing ring expands to the outside of the first annular groove.

5. The high-precision and long-life tension and pressure sensor according to claim 4, characterized in that: The bottom end of the elastomer is provided with an opening and a cover plate is fixed in the opening by a plurality of fastening bolts, the cover plate is arranged in the concave edge of the opening at the bottom end of the elastomer, and an annular step is integrally formed on the top of the cover plate on one side corresponding to the slot, the annular step is inserted into the slot, and the annular step covers the vertical extension portion, the inner wall of the annular step is interference fit with the first sealing ring on the outer periphery of the vertical extension portion, the annular step, the first sealing ring and the slot are used in combination to form a first sealing structure between the opening at the bottom end of the elastomer and the cover plate.

6. The high-precision and long-life tension and pressure sensor according to claim 5, characterized in that: A waterproof joint is provided on one side of the elastomer, and a through hole is provided on the inner wall of the elastomer on one side corresponding to the waterproof joint, and an internal thread is provided in the through hole. The waterproof joint is a hollow tubular structure and an external thread is provided at one end thereof corresponding to the through hole. The external thread is used in conjunction with the internal thread to tighten and fix the waterproof joint. A second annular groove is provided on the outer end of the waterproof joint corresponding to the external thread, and a second sealing ring is fixed in the second annular groove. The second sealing ring expands outward and has an interference fit with the through hole to seal the through hole and block the gap at the threaded connection between the waterproof joint and the through hole. The second sealing ring is used in conjunction with the through hole to form a second sealing structure between the elastomer and the waterproof joint.

7. The high-precision and long-life tension and pressure sensor according to claim 6, characterized in that: An end cap is integrally formed at one end of the waterproof connector away from the through hole, a plurality of wire holes are formed on the end cap, and the wires are inserted into the plurality of wire holes, one end of the wire is connected to the resistive strain gauge and the other end is connected to an external measurement circuit, a third sealing ring is fixed at the gap between the wire hole and the wire, the third sealing ring is used to block the gap left when the wire passes through the end cap and keep the end cap sealed, and the third sealing ring is used in conjunction with the wire hole to form a third sealing structure at the end cap.

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