Tension and compression force sensor with compensation function

Abstract

The present application relates to tension and compression force sensor field, specifically is tension and compression force sensor with compensation function, including elastomer, strain gauge, compensation sheet and terminal; Strain gauge and compensation sheet are arranged on the surface of elastomer respectively, strain gauge, compensation sheet and terminal are electrically connected through multiple high-temperature-resistant cables to form bridge circuit, at least strain gauge and compensation sheet are limited in first heat insulation layer and protective layer respectively, first heat insulation layer is located between elastomer and protective layer. At least through first heat insulation layer for protection, heat insulation, pressure resistance, sealing, strain gauge and compensation sheet packaged with polyimide film and meeting 260 degree high temperature resistance are wrapped, so that the actual temperature of strain gauge and compensation sheet has significant temperature difference with current environment temperature, the actual temperature of strain gauge and compensation sheet is significantly lower than environment temperature, so that strain gauge and compensation sheet are respectively in ideal temperature range, which guarantees the force measurement accuracy of the tension and compression force sensor.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of tension and pressure sensors, in particular to a tension and pressure sensor with compensation function. BACKGROUND

[0002] A tension and pressure sensor is a device used to measure the magnitude of tension or pressure on an object. It converts the physical tension into an electrical signal for measurement and control. The working principle is mainly based on the characteristic that the resistance value of a strain gauge (or strain meter) changes when it is subjected to external force. Specifically, when the strain gauge is subjected to tension or pressure, the internal metal conductor (usually a filament or foil) will undergo a slight deformation. This deformation causes changes in the length and cross-sectional area of the conductor, which in turn causes changes in the resistance value. The change in resistance value is directly proportional to the magnitude of the external force, so the magnitude of the tension or pressure can be calculated by measuring the change in resistance value.

[0003] In a tension and pressure sensor, two or four strain gauges are usually connected together in a certain way (such as full-bridge or half-bridge circuit) to form an electric bridge circuit. When the sensor is subjected to tension or pressure, the resistance values of the individual strain gauges change, causing the output voltage of the electric bridge circuit to change. This output voltage signal is then amplified, processed, and converted into a readable force value display or used in a control system.

[0004] Temperature compensation is crucial in the actual use of tension and pressure sensors. The main reason is that temperature changes can significantly interfere with the measurement accuracy of the sensor, producing false signals unrelated to the actual force. The common method in the prior art is to use a constantan wire in series in the bridge circuit for correction and compensation, but its compensation temperature range is narrow, generally not exceeding 120℃, making it difficult to meet the use of sensors in harsh high-temperature environments, such as the oil well drilling field, where the downhole temperature can reach as high as 260℃. Obviously, the technical solution of using a constantan wire in series cannot meet the application in an environment with a temperature of 260℃.

[0005] Therefore, how to improve the high-temperature resistance of tension and pressure sensors has become a technical problem to be solved. SUMMARY

[0006] To solve the technical problem of how to improve the high-temperature resistance of tension and pressure sensors, the present application provides a tension and pressure sensor with compensation function.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows:

[0008] According to one aspect of the present application, a tension and pressure sensor with compensation function is provided, comprising an elastic body, a strain gauge, a compensation sheet, and a terminal.

[0009] The strain gauge and the compensation gauge are respectively arranged on the surface of the elastic body, and the strain gauge, the compensation gauge and the terminal are electrically connected by a plurality of high-temperature-resistant cables to form a bridge circuit, wherein at least the strain gauge and the compensation gauge are respectively limited in a first thermal insulation layer and a protective layer, and the first thermal insulation layer is located between the elastic body and the protective layer.

[0010] The terminal is arranged in the first thermal insulation layer and the protective layer.

[0011] The strain gauge and the compensation gauge are respectively packaged by a polyimide film and meet the condition of resisting 260-degree high temperature.

[0012] Further, the first thermal insulation layer is made of thermal insulation glue.

[0013] The first thermal insulation layer comprises a first glue layer and a second glue layer.

[0014] At the position of the strain gauge, the first glue layer is located between the elastic body and the strain gauge, the strain gauge is bonded to the elastic body through the first glue layer, the contour of the strain gauge is located in the contour of the first glue layer, and the second glue layer covers the strain gauge and the first glue layer.

[0015] At the position of the compensation gauge, the first glue layer is located between the elastic body and the compensation gauge, the compensation gauge is bonded to the elastic body through the first glue layer, the contour of the compensation gauge is located in the contour of the first glue layer, and the second glue layer covers the compensation gauge and the second glue layer.

[0016] Further, the connection positions of the strain gauge and the high-temperature-resistant cable, the connection positions of the compensation gauge and the high-temperature-resistant cable, and the connection positions of the terminal and the high-temperature-resistant cable are respectively welded by high-temperature solder, and are respectively covered by the first thermal insulation layer, wherein each welding point formed by the high-temperature solder is covered by the first thermal insulation layer.

[0017] Further, the elastic body is provided with a wire hole and a twisted wire, one end of the twisted wire passes out of the wire hole along the direction from the inside to the outside of the elastic body, the twisted wire located outside the wire hole is electrically connected to the terminal, and the connection position of the twisted wire and the terminal is welded by the high-temperature solder.

[0018] The connection positions of the terminal and the high-temperature-resistant cable, the connection positions of the terminal and the twisted wire, and the wire hole are respectively covered by high-temperature silicone rubber, wherein the high-temperature silicone rubber is located outside the first thermal insulation layer.

[0019] Further, a housing is further included.

[0020] The number of the shells is 2, the two shells are defined as a first shell and a second shell respectively, the two shells are used to cover at least the strain gauges, the compensation gauges, the terminal, the first thermal insulation layer and a part of the elastic body, and the two shells form gaps with the elastic body respectively;

[0021] The two shells are wrapped by the protective layer, wherein the protective layer is a tape made of polyimide material.

[0022] Further, the elastic body is provided with a first connecting section, an intermediate section and a second connecting section, and the intermediate section is located between the first connecting section and the second connecting section.

[0023] The intermediate section is processed with a first mounting surface, a second mounting surface, a third mounting surface, a fourth mounting surface, a fifth mounting surface, a sixth mounting surface and a seventh mounting surface.

[0024] The first mounting surface and the second mounting surface are respectively planes, and the first mounting surface and the second mounting surface are arranged back to back, the number of the strain gauges is 4, and the four strain gauges are defined as a first strain gauge, a second strain gauge, a third strain gauge and a fourth strain gauge respectively, the first strain gauge and the second strain gauge are pasted on the first mounting surface, and the third strain gauge and the fourth strain gauge are pasted on the second mounting surface.

[0025] On the first mounting surface, the length direction of the first strain gauge is parallel to the axial direction of the elastic body, and the length direction of the second strain gauge is perpendicular to the axial direction of the elastic body, on the second mounting surface, the length direction of the third strain gauge is parallel to the axial direction of the elastic body, and the length direction of the fourth strain gauge is perpendicular to the axial direction.

[0026] The third mounting surface and the first mounting surface are located on the same side of the elastic body respectively, the fourth mounting surface and the second mounting surface are located on the same side of the elastic body respectively, the fifth mounting surface is located on the surface of a part of the elastic body between the first mounting surface and the second mounting surface, the number of the compensation gauges is 3, and the three compensation gauges are defined as a zero compensation gauge, a zero temperature compensation gauge and a sensitivity temperature compensation gauge respectively, the zero temperature compensation gauge is pasted on the third mounting surface, the zero compensation gauge is pasted on the fourth mounting surface, and the sensitivity temperature compensation gauge is pasted on the fifth mounting surface.

[0027] The sixth mounting surface and the seventh mounting surface are away from each other, the third mounting surface, the sixth mounting surface, the fourth mounting surface and the seventh mounting surface are sequentially spaced around the elastic body, the number of the terminal is two, the two terminals are defined as a first terminal and a second terminal respectively, the first terminal is arranged on the sixth mounting surface, and the second terminal is arranged on the seventh mounting surface respectively;

[0028] The number of the wire passing holes is two, the two wire passing holes are defined as a first wire passing hole and a second wire passing hole respectively, the first wire passing hole is recessed on the sixth mounting surface, and the second wire passing hole is recessed on the seventh mounting surface;

[0029] The first shell and the second shell jointly cover the first mounting surface to the seventh mounting surface.

[0030] Further, the first strain gauge is electrically connected with the zero temperature compensation sheet, the second terminal, and the fourth strain gauge respectively;

[0031] The second strain gauge is electrically connected with the zero temperature compensation sheet, the sensitivity temperature compensation sheet, and the third strain gauge respectively;

[0032] The third strain gauge is electrically connected with the second strain gauge, the zero compensation sheet, and the sensitivity temperature compensation sheet respectively;

[0033] The fourth strain gauge is electrically connected with the zero compensation sheet, the second terminal, and the first strain gauge respectively;

[0034] The zero temperature compensation sheet and the zero compensation sheet are electrically connected with the first terminal respectively.

[0035] Further, the first connecting section and the second connecting section are respectively provided with external threads;

[0036] The elastic body is further provided with mounting channels, the mounting channels form port portions at two ends of the elastic body respectively, and the mounting channels are connected with the first wire passing hole and the second wire passing hole in the elastic body respectively;

[0037] One section of the twisted wire is limited in the mounting channel.

[0038] Further, the elastomer is limited to an elastomer under a load of -20000 pounds force to +20000 pounds force, wherein the elastomer is limited to an elastomer made of stainless steel 17-4PH with a hardness between HRC 44 to HRC 48, when the elastomer receives a force in a range of zero pounds to +20000 pounds, the force received by the elastomer is a pulling force, when the elastomer receives a force in a range of zero pounds to -20000 pounds, the force received by the elastomer is a pressure force. The above technical solutions have the following advantages or beneficial effects:

[0039] The pull and pressure sensor with compensation function provided by the present application is actually applied to an environment with a temperature of 260 DEG C. When the elastomer is deformed, the elastomer drives the strain gauge to deform, so as to change the resistance value of the strain gauge. At the same time, since the strain gauge and the compensation sheet have the same temperature and form a bridge circuit, the temperature deviation is automatically eliminated, and the temperature compensation effect is formed. At least by the first heat insulation layer for protection, heat insulation, pressure resistance and sealing, the strain gauge and the compensation sheet packaged by the polyimide film meet the requirement of 260 DEG C high temperature resistance. The actual temperature of the strain gauge and the compensation sheet has a significant temperature difference with the current environment temperature, and the actual temperature of the strain gauge and the compensation sheet is significantly lower than the environment temperature. The strain gauge and the compensation sheet are respectively arranged in an ideal temperature range, so as to ensure the force measurement accuracy of the pull and pressure sensor of the embodiment, and solve the technical problem of how to improve the high temperature resistance of the pull and pressure sensor. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 The structure diagram of the pull and pressure sensor with compensation function provided by the present application is shown in the figure.

[0041] Figure 2 The structure diagram of the pull and pressure sensor with compensation function provided by the present application is shown in the figure.

[0042] Figure 3 The structure diagram of the pull and pressure sensor with compensation function provided by the present application is shown in the figure.

[0043] Figure 4 The structure diagram of the pull and pressure sensor with compensation function provided by the present application is shown in the figure.

[0044] Figure 5 The structure diagram of the pull and pressure sensor with compensation function provided by the present application is shown in the figure.

[0045] Figure 6 The electrical connection diagram of the pull and pressure sensor with compensation function provided by the present application is shown in the figure.

[0046] Figure 7A structural schematic diagram of the tensile and compressive force sensor with compensation function provided in the embodiment of the present application is shown in the figure.

[0047] Figure 8 A sectional view of the tensile and compressive force sensor with compensation function provided in the embodiment of the present application is shown in the figure.

[0048] Figure 9 A sectional view of the tensile and compressive force sensor with compensation function provided in the embodiment of the present application is shown in the figure.

[0049] Reference numerals: 0, twisted wire; 1, elastomer; 2, strain gauge; 3, compensation sheet; 4, terminal; 5, wire hole; 6, high-temperature silicone rubber; 7, shell; 8, mounting channel; 9, wire slot.

[0050] 11, first connecting section; 12, intermediate section; 13, second connecting section; 21, first strain gauge; 22, second strain gauge; 23, third strain gauge; 24, fourth strain gauge; 31, zero-point compensation sheet; 32, zero-point temperature compensation sheet; 33, sensitivity temperature compensation sheet; 41, first terminal; 42, second terminal; 51, first wire hole; 52, second wire hole; 71, first shell; 72, second shell.

[0051] 100, first heat insulation layer; 121, first mounting surface; 122, second mounting surface; 123, third mounting surface; 124, third mounting surface; 125, fifth mounting surface; 126, sixth mounting surface; 127, seventh mounting surface; 200, protective layer. DETAILED DESCRIPTION

[0052] Embodiment 1

[0053] In the embodiment, a tensile and compressive force sensor with compensation function is provided, by setting multiple heat insulation structures, the strain gauges and compensation sheets are respectively improved in high-temperature resistance, so that the technical effect of improving the high-temperature resistance of the tensile and compressive force sensor is achieved.

[0054] Specifically, the tensile and compressive force sensor with compensation function of the embodiment, referring to Figure 1 、 Figure 8 or Figure 9 ,

[0055] includes an elastomer 1, a strain gauge 2, a compensation sheet 3, and a terminal 4.

[0056] The strain gauge 2 and the compensation sheet 3 are respectively arranged on the surface of the elastomer 1, and the strain gauge 2, the compensation sheet 3, and the terminal are electrically connected by multiple high-temperature-resistant cables to form a bridge circuit, wherein at least the strain gauge 2 and the compensation sheet 3 are respectively limited in the first heat insulation layer 100 and the protective layer 200, and the first heat insulation layer 100 is located between the elastomer 1 and the protective layer 200.

[0057] The terminal 4 is arranged in the first thermal insulation layer 100 and the protective layer 200;

[0058] The strain gauge 2 and the compensation gauge 3 are respectively packaged by polyimide film and meet the condition of resisting 260-degree high temperature.

[0059] In the embodiment, the compensation gauge 3 is used to replace the constantan wire in the prior art, but the principles of the two are obviously different, which is the common knowledge of the person skilled in the art; the compensation gauge 3 is usually a metal film resistor or a close alloy resistor, and the resistance range is relatively wide; the compensation gauge 3 is used in cooperation with the strain gauge 2, the resistance value of the compensation gauge 3 is adjusted to offset the influence of temperature change or asymmetric strain, so as to improve the measurement accuracy of the tension and compression force sensor; see Figure 6 The compensation gauge 3, the strain gauge 2 and the high-temperature-resistant cable constitute a bridge circuit, because the compensation gauge 3 and the strain gauge 2 are made of the same material and have the same working environment temperature, the bridge circuit can automatically eliminate the temperature deviation and the nonlinear error.

[0060] In the embodiment, see Figure 8 or Figure 9 The strain gauge 2 and the compensation gauge 3 are completely surrounded by the first thermal insulation layer 100; more specifically, one side of the strain gauge 2 facing the elastomer 1 is defined as a first side, and the other side of the strain gauge 2 away from the elastomer 1 is defined as a second side, the first thermal insulation layer 100 covers not only the second side but also the first side, so that the strain gauge 2 is entirely wrapped in the first thermal insulation layer 100; similarly, one side of the compensation gauge 3 facing the elastomer 1 is defined as a third side, and the other side of the compensation gauge 3 away from the elastomer 1 is defined as a fourth side, the first thermal insulation layer 100 covers not only the fourth side but also the third side, so that the compensation gauge 3 is entirely wrapped in the first thermal insulation layer 100.

[0061] In the embodiment, see Figure 8 or Figure 9 The protective layer 200 is wrapped at the overlapping position of the elastomer 1, the strain gauge 2, the compensation gauge 3 and the high-temperature-resistant cable (specifically, the intermediate section 12 described later), so that the protective layer 200 wraps the high-temperature-resistant cable, the first thermal insulation layer 100 and the strain gauge 2 and the compensation gauge 3 located in the first thermal insulation layer 100.

[0062] See Figure 8 or Figure 9, between the elastic body 1 and the strain gauge 2, and between the elastic body 1 and the compensation gauge 3, are respectively isolated by a part of the first thermal insulation layer 100, which makes the heat of the elastic body 1 isolated by the first thermal insulation layer 100 in the process of the heat of the elastic body 1 transferring to the strain gauge 2 along the direction of the elastic body 1 to the strain gauge 2, resulting in a temperature difference between the temperature of the elastic body 1 and the actual temperature of the strain gauge 2, and the temperature of the elastic body 1 is higher than the actual temperature of the strain gauge 2; similarly, in the process of the heat of the elastic body 1 transferring to the compensation gauge 3 along the direction of the elastic body 1 to the compensation gauge 3, the heat of the elastic body 1 is isolated by the first thermal insulation layer 100, resulting in a temperature difference between the temperature of the elastic body 1 and the actual temperature of the compensation gauge 3, and the temperature of the elastic body 1 is higher than the actual temperature of the compensation gauge 3;

[0063] between the 260℃ environment medium and the strain gauge 2, and between the 260℃ environment medium and the compensation gauge 3, on the one hand, both are respectively isolated by the first thermal insulation layer 100 and the protective layer 200, which makes the heat of the environment medium isolated by the protective layer 200 first and then isolated by the first thermal insulation layer 100 in the process of the heat of the environment medium transferring to the strain gauge 2 along the direction of the environment medium to the strain gauge 2, resulting in a temperature difference between the temperature of the environment medium and the actual temperature of the strain gauge 2, and the temperature of the environment medium is higher than the actual temperature of the strain gauge 2; similarly, in the process of the heat of the environment medium transferring to the compensation gauge 3 along the direction of the environment medium to the compensation gauge 3, the heat of the environment medium is isolated by the protective layer 200 first and then isolated by the first thermal insulation layer 100, resulting in a temperature difference between the temperature of the environment medium and the actual temperature of the compensation gauge 3, and the temperature of the environment medium is higher than the actual temperature of the compensation gauge 3; on the other hand, the protective layer 200 isolates the heat of the environment medium from the high-temperature-resistant cable, resulting in a temperature difference between the temperature of the environment medium and the actual temperature of the high-temperature-resistant cable, and the temperature of the environment medium is higher than the actual temperature of the high-temperature-resistant cable.

[0064] In the actual application of the tensile and compressive force sensor with the compensation gauge 3 in the environment with a temperature of 260℃, the elastic body 1 is deformed to make the elastic body 1 drive the strain gauge 2 to deform, thereby changing the resistance value of the strain gauge 2; at the same time, since the strain gauge 2 and the compensation gauge 3 have the same temperature and form a bridge circuit, the temperature deviation is automatically eliminated, and the temperature compensation effect is formed; at least by the first thermal insulation layer 100 for protection, thermal insulation, pressure resistance, and sealing, the strain gauge 2 and the compensation gauge 3 packaged by the polyimide film and meeting the requirement of 260-degree high-temperature resistance are wrapped, so that the actual temperature of the strain gauge 2 and the compensation gauge 3 has a significant temperature difference with the current environment temperature, and the actual temperature of the strain gauge 2 and the compensation gauge 3 is significantly lower than the environment temperature, which makes the strain gauge 2 and the compensation gauge 3 respectively in the ideal temperature range, and ensures the force measurement accuracy of the tensile and compressive force sensor. The technical problem of how to improve the high-temperature resistance of the tensile and compressive force sensor is solved.

[0065] Further, the tensile and compressive force sensor with the compensation sheet 3 of the present embodiment adopts the heat insulation glue for the first heat insulation layer 100;

[0066] The first heat insulation layer 100 includes a first glue layer and a second glue layer;

[0067] At the position of the strain sheet 2, the first glue layer is located between the elastic body 1 and the strain sheet 2, the strain sheet 2 is bonded to the elastic body 1 through the first glue layer, the contour of the strain sheet 2 is located within the contour of the first glue layer, and the second glue layer covers the strain sheet 2 and the first glue layer;

[0068] At the position of the compensation sheet 3, the first glue layer is located between the elastic body 1 and the compensation sheet 3, the compensation sheet 3 is bonded to the elastic body 1 through the first glue layer, the contour of the compensation sheet 3 is located within the contour of the first glue layer, and the second glue layer covers the compensation sheet 3 and the second glue layer.

[0069] The heat insulation glue can adopt the heat insulation glue suitable for the tensile and compressive force sensor in the prior art; in the present embodiment, the heat insulation glue has two functions, the first function is to serve as the material of the first heat insulation layer 100 for isolating the temperature of the environmental medium, and the second function is to serve as the adhesive for bonding the strain sheet 2 and the compensation sheet 3 on the elastic body 1.

[0070] In the actual manufacturing of the tensile and compressive force sensor of the present embodiment, after obtaining the elastic body 1, the strain sheet 2 and the compensation sheet 3, first, the heat insulation glue is coated on the elastic body 1 once, thereby forming the first glue layer, then, the strain sheet 2 or the compensation sheet 3 is bonded on the first glue layer, thereby forming the connection of the strain sheet 2 or the compensation sheet 3 relative to the elastic body 1; next, the heat insulation glue is coated on the first glue layer and the strain sheet 2, or on the first glue layer and the compensation sheet 3 again, thereby forming the second glue layer; the area of the first glue layer and the area of the second glue layer are respectively greater than the area of the strain sheet 2 and the area of the compensation sheet 3, so that the first glue layer and the second glue layer can completely wrap the strain sheet 2 or the compensation sheet 3;

[0071] It should be understood that, in order to improve the heat insulation effect, the method of coating the heat insulation glue multiple times can be adopted, so that the second glue layer is thickened; for example, after the heat insulation glue is coated on the first glue layer and the strain sheet 2, or on the first glue layer and the compensation sheet 3 once for the first time, the heat insulation glue is allowed to dry, the operation of coating the heat insulation glue for the second time can be performed, and so on, the coating of the heat insulation glue for three layers or five layers is performed to form a relatively thick second glue layer, and the heat insulation effect of the second glue layer is increased.

[0072] Further, the strain gauge 2 and the high-temperature cable are connected at a first connection position, the compensation sheet 3 and the high-temperature cable are connected at a second connection position, and the terminal 4 and the high-temperature cable are connected at a third connection position. The first connection position, the second connection position, and the third connection position are respectively covered by a first thermal insulation layer 100. Each of the first connection position, the second connection position, and the third connection position is covered by the first thermal insulation layer 100.

[0073] The high-temperature solder is a proper noun. The melting point of the high-temperature solder is higher than that of the common solder. Thus, the melting point of the solder formed by the high-temperature solder can withstand a higher temperature.

[0074] The solder formed by the connection of the strain gauge 2 and the high-temperature cable, the solder formed by the connection of the compensation sheet 3 and the high-temperature cable, and the solder formed by the connection of the terminal 4 and the high-temperature cable are respectively covered by the first thermal insulation layer 100. Thus, the first thermal insulation layer 100 wraps each of the solders to isolate the heat of the environmental medium, avoids the temperature difference between each of the solders and the strain gauge 2 or the compensation sheet 3, and further avoids interfering with the detection accuracy of the force of the tension and compression force sensor.

[0075] Further, referring to Figures 1 to 5 , Figure 7 or Figure 9 , the tension and compression force sensor of the present embodiment is provided with the compensation sheet 3. The elastic body 1 is provided with a wire hole 5 and a wire 0. One end of the wire 0 extends out of the wire hole 5 along the direction from the inside to the outside of the elastic body 1. The wire 0 outside the wire hole 5 is electrically connected to the terminal 4. The connection position of the wire 0 and the terminal 4 is welded by the high-temperature solder.

[0076] The connection position of the terminal 4 and the high-temperature cable, the connection position of the terminal 4 and the wire 0, and the wire hole 5 are covered by a high-temperature silicone rubber 6. The high-temperature silicone rubber 6 is located outside the first thermal insulation layer 100.

[0077] The wire 0 is a signal transmission path connecting the terminal 4 and an external control system. One end of the wire 0 is connected to the terminal 4. The other end of the wire 0 extends to the outside of the elastic body 1 through the wire hole 5. The connection position of the wire 0 and the terminal 4 is a solder point formed by the high-temperature solder, which is also covered by the first thermal insulation layer 100.

[0078] Referring to Figure 9The connection points of terminal 4 with the high-temperature resistant cable, the connection points of terminal 4 with stranded wire 0, and the wire hole 5 are respectively covered by high-temperature silicone rubber 6. On the one hand, the high-temperature silicone rubber 6 is located outside the first heat insulation layer 100, thereby playing a reinforced heat insulation role between the first heat insulation layer 100 and the protective layer 200. On the other hand, the high-temperature silicone rubber 6 also has a good insulation effect. By covering the high-temperature silicone rubber 6, the stranded wire 0, the high-temperature resistant cable and the terminal 4 are fixed and sealed.

[0079] Further, see Figure 8 or Figure 9 The tensile and compressive sensor with compensation piece 3 in this embodiment also includes housing 7;

[0080] The housing 7 is used to cover at least the strain gauge 2, the compensation plate 3, the wiring terminal 4, the first heat insulation layer 100, and a portion of the elastomer 1 therein;

[0081] The housing 7 is wrapped with a protective layer 200, which is specifically a tape made of polyimide material.

[0082] The main function of the housing 7 is to improve the support strength and protect the strain gauge 2, the compensation plate 3, the high-temperature resistant cable, the terminal 4, and the first heat insulation layer 100 between the first heat insulation layer 100 and the protective layer 200; when subjected to external impact and compression, the housing 7 absorbs the energy of the external force; the second function of the housing 7 is to provide a base for winding the protective layer 200.

[0083] The connection structure between the housing 7 and the elastomer 1 can adopt existing connection structures, such as snap-fit ​​connection, adhesive connection, etc. Preferably, the housing 7 and the elastomer 1 are filled with the aforementioned high-temperature silicone rubber so that the housing 7 and the elastomer 1 do not contact each other, and then the housing 7 can be fixed relative to the elastomer 1 by wrapping the protective layer 200.

[0084] In this embodiment, the protective layer 200 is made of polyimide film. Polyimide film is a high molecular polymer that can withstand temperatures above 400°C, has a long-term operating temperature range of -200 to 300°C, and some parts have no obvious melting point, exhibiting high insulation performance. Polyimide is an excellent thermal insulation material. In the scheme where the protective layer 200 is wrapped around the shell 7, the protective layer 200 mainly serves to fix the shell 7 (specifically the first shell 71 and the second shell 71) relative to the elastomer 1, and then has a small portion of heat insulation function.

[0085] Further, see Figures 2 to 4 , Figure 6 or Figure 7The tensile and compressive force sensor with the compensation sheet 3 has the elastic body 1 provided with the first connecting section 11, the middle section 12 and the second connecting section 13, and the middle section 12 is located between the first connecting section 11 and the second connecting section 13;

[0086] The middle section 12 is processed with the first mounting surface 121, the second mounting surface 122, the third mounting surface 123, the fourth mounting surface 124, the fifth mounting surface 125, the sixth mounting surface 126 and the seventh mounting surface 127;

[0087] The first mounting surface 121 and the second mounting surface 122 are respectively planes, and the first mounting surface 121 and the second mounting surface 122 are arranged back to back, the number of the strain sheets 2 is 4, and the 4 strain sheets 2 are respectively defined as the first strain sheet 21, the second strain sheet 22, the third strain sheet 23 and the fourth strain sheet 24, the first strain sheet 21 and the second strain sheet 22 are pasted on the first mounting surface 121, and the third strain sheet 23 and the fourth strain sheet 24 are pasted on the second mounting surface 122;

[0088] The third mounting surface 123 and the first mounting surface 121 are respectively located on the same side of the elastic body 1, the fourth mounting surface 124 and the second mounting surface 122 are respectively located on the same side of the elastic body 1, the fifth mounting surface 125 is located on the surface of a part of the elastic body 1 between the first mounting surface 121 and the second mounting surface 122, the number of the compensation sheets 3 is 3, and the 3 compensation sheets 3 are respectively defined as the zero point compensation sheet 31, the zero point temperature compensation sheet 32 and the sensitivity temperature compensation sheet 33, the zero point temperature compensation sheet 32 is pasted on the third mounting surface 123, the zero point compensation sheet 31 is pasted on the fourth mounting surface 124, and the sensitivity temperature compensation sheet 33 is pasted on the fifth mounting surface 125;

[0089] The sixth mounting surface 126 and the seventh mounting surface 127 are away from each other, the third mounting surface 123, the sixth mounting surface 126, the fourth mounting surface 124 and the seventh mounting surface 127 are sequentially and spacedly surrounded on the elastic body 1, the number of the wiring terminals 4 is 2, and the 2 wiring terminals 4 are respectively defined as the first wiring terminal 41 and the second wiring terminal 42, the first wiring terminal 41 is arranged on the sixth mounting surface 126, and the second wiring terminal 42 is respectively arranged on the seventh mounting surface 127;

[0090] The number of the wire passing holes 5 is 2, and the 2 wire passing holes 5 are respectively defined as the first wire passing hole 51 and the second wire passing hole 52, the first wire passing hole 51 is recessed on the sixth mounting surface 126, and the second wire passing hole 52 is recessed on the seventh mounting surface 127;

[0091] The number of the housings 7 is 2, and the 2 housings 7 are respectively defined as the first housing 71 and the second housing 72, and the first housing 71 and the second housing 72 jointly cover the first mounting surface 121 to the seventh mounting surface 127.

[0092] Referring to Figure 2 or Figure 3 The first mounting surface 121 and the second mounting surface 122 are arranged in a back-to-back structure, so that the strain gauges 2 arranged on the first mounting surface 121 and the strain gauges 2 arranged on the second mounting surface 122 have the same deformation effect; on the first mounting surface 121, the length direction of the first strain gauge 21 is parallel to the axial direction, and the length direction of the second strain gauge 22 is perpendicular to the axial direction; correspondingly, on the second mounting surface 122, the length direction of the third strain gauge 23 is parallel to the axial direction, and the length direction of the fourth strain gauge 24 is perpendicular to the axial direction; in this way, the first strain gauge 21 and the third strain gauge 23 are used to directly measure the axial strain caused by tension or pressure, and the second strain gauge 22 and the fourth strain gauge 24 cooperate with the first strain gauge 21 and the third strain gauge 23 to form a bridge circuit; by using Poisson's effect, when the elastic body 1 is subjected to an axial force and generates an opposite strain, the bridge circuit can amplify the output signal to improve the sensitivity and help to enhance the temperature compensation effect (because the temperature affects all strain gauges 2 equally, and the effects are offset in the bridge circuit).

[0093] The positions of the four strain gauges 2 arranged on the first mounting surface 121 or the second mounting surface 122 can be determined by finite element simulation to calculate the maximum stress concentration area of the elastic body 1, and then the strain gauges 2 are pasted on the maximum stress concentration area of the elastic body 1, and then the stress detection is carried out by external loading experiment, so as to determine whether the current position of the strain gauge 2 is reasonable.

[0094] Referring to Figure 6 The four strain gauges 2 form a bridge circuit (more specifically, a full-bridge circuit), which itself has high sensitivity, excellent temperature automatic compensation performance, excellent linearity and strong anti-interference ability, and is suitable for measurement under complex stress state; on this basis, the zero temperature compensation sheet 32, the zero compensation sheet 31 and the sensitivity temperature compensation sheet 33 are respectively used to further enhance the temperature compensation ability of the tension and compression force sensor of the embodiment, and to ensure the normal use of the sensor in a high temperature environment.

[0095] The two wire passing holes 5 are preferably arranged in an inclined manner to increase the angle between the center line of the wire passing hole 5 and the center line of the elastic body 1, so as to avoid the excessive bending of the wire 0 or reduce the difficulty of the wire 0 passing through the wire passing hole 5.

[0096] In the embodiment, the first to seventh mounting surfaces 127 are arranged at the position of the middle section 12, which makes the most of the space structure of the middle section 12, and realizes the concentrated arrangement of the strain gauges 2, the compensation sheets 3 and the wire terminals 4.

[0097] Further, referring to Figure 6The tensile and compressive force sensor with the compensation sheet 3 in the embodiment has the first strain sheet 21 electrically connected with the zero temperature compensation sheet 32, the second connecting terminal 42 and the fourth strain sheet 24 respectively.

[0098] The second strain sheet 22 is electrically connected with the zero temperature compensation sheet 32, the sensitivity temperature compensation sheet 33 and the third strain sheet 23 respectively.

[0099] The third strain sheet 23 is electrically connected with the second strain sheet 22, the zero compensation sheet 31 and the sensitivity temperature compensation sheet 33 respectively.

[0100] The fourth strain sheet 24 is electrically connected with the zero compensation sheet 31, the second connecting terminal 42 and the first strain sheet 21 respectively.

[0101] The zero temperature compensation sheet 32 and the zero compensation sheet 31 are electrically connected with the first connecting terminal 41 respectively.

[0102] In the embodiment, the four strain sheets 2, the three compensation sheets 3 and the two connecting terminals 4 are connected to form a bridge circuit, and then the compensation sheet 3 is adjusted in resistance. The following provides a specific parameter after resistance adjustment for understanding by those skilled in the art:

[0103] The resistance between the first and second twisted wires after adjustment is 1070Ω, the resistance between the first and fourth twisted wires is 820Ω, the resistance between the third and fourth twisted wires is 1000Ω, and the resistance between the second and fourth twisted wires is 750Ω.

[0104] Further, referring to Figure 7 The tensile and compressive force sensor with the compensation sheet 3 in the embodiment has the first connecting section 11 and the second connecting section 13 respectively machined with external threads.

[0105] The elastic body 1 is further provided with mounting channels 8, the mounting channels 8 respectively form mouth portions at two ends of the elastic body 1, and the connection positions of the mounting channels 8 with the first wire passing hole 51 and the second wire passing hole 52 are located in the elastic body 1.

[0106] One section of the twisted wire 0 is limited in the mounting channel 8.

[0107] The first connecting section 11 and the second connecting section 13 are respectively provided with external threads, which is convenient for connecting the interface of the test equipment. Preferably, the end surface of the first connecting section 11 and the end surface of the second connecting section 13 are respectively provided with wire passing grooves 9, which are used for the aforementioned twisted wire 0 to pass through.

[0108] The installation channel 8 is used to guide the wire 0 from the inside of the elastic body 1 to the outside of the elastic body 1; in actual installation, the wire 0 is arranged as four, and all the four wires 0 can be guided to the outside of the elastic body 1 through the port of one end of the elastic body 1, or two wires 0 can be guided to the outside of the elastic body 1 through the port of the end of the first connecting section 11 of the elastic body 1, and the other two wires 0 can be guided to the outside of the elastic body 1 through the port of the end of the second connecting section 13 of the elastic body 1; corresponding to the two wire passing holes 5, two wires 0 are connected to the first terminal 4 through the first wire passing hole 5, and the other two wires 0 are connected to the second terminal 4 through the second wire passing hole 5.

[0109] Further, the tension and compression force sensor with the compensation sheet 3 of the embodiment is limited to the elastic body 1 under the load of 20000 pounds, wherein the elastic body 1 is limited to the elastic body made of stainless steel 17-4PH with the hardness between HRC44 and HRC48, when the elastic body 1 receives the force in the range of 0 pound to 20000 pounds, the force received by the elastic body 1 is tension, and when the elastic body 1 receives the force in the range of 0 pound to 20000 pounds, the force received by the elastic body 1 is compression.

[0110] Wherein, after the material of the elastic body 1 is selected as stainless steel 17-4PH, the hardness of the elastic body 1 is limited to between HRC44 and HRC48 through heat treatment, so that the elastic body 1 can meet the load of 20000 pounds.

[0111] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation or direct or indirect application in other related technical fields based on the content of the specification and drawings of the present application is also included in the patent protection scope of the present application.

Claims

1. A tension / compression sensor with compensation function, characterized in that, Includes elastomers, strain gauges, compensating plates, and terminals; The strain gauge and the compensation plate are respectively disposed on the surface of the elastic body. The strain gauge, the compensation plate and the terminal are electrically connected by multiple high-temperature resistant cables to form a bridge circuit. At least the strain gauge and the compensation plate are respectively confined within a first heat insulation layer and a protective layer. The first heat insulation layer is located between the elastic body and the protective layer. The wiring terminals are disposed within the first heat insulation layer and the protective layer; The strain gauge and the compensation plate are respectively encapsulated with polyimide film and meet the requirement of withstanding a high temperature of 260 degrees Celsius. The elastomer is provided with a first connecting segment, an intermediate segment, and a second connecting segment, wherein the intermediate segment is located between the first connecting segment and the second connecting segment; The intermediate section is machined with a first mounting surface, a second mounting surface, a third mounting surface, a fourth mounting surface, a fifth mounting surface, a sixth mounting surface, and a seventh mounting surface; The number of strain gauges is four, and the four strain gauges are respectively defined as the first strain gauge, the second strain gauge, the third strain gauge and the fourth strain gauge. The first strain gauge and the second strain gauge are attached to the first mounting surface, and the third strain gauge and the fourth strain gauge are attached to the second mounting surface. The number of compensation plates is three, and the three compensation plates are respectively defined as zero-point compensation plate, zero-point temperature compensation plate and sensitivity temperature compensation plate. The zero-point temperature compensation plate is attached to the third mounting surface, the zero-point compensation plate is attached to the fourth mounting surface, and the sensitivity temperature compensation plate is attached to the fifth mounting surface. The number of terminals is two, and the two terminals are respectively defined as the first terminal and the second terminal. The first terminal is provided on the sixth mounting surface, and the second terminal is provided on the seventh mounting surface. The first strain gauge is electrically connected to the zero-point temperature compensation gauge, the second terminal, and the fourth strain gauge, respectively. The second strain gauge is electrically connected to the zero-point temperature compensation gauge, the sensitivity temperature compensation gauge, and the third strain gauge, respectively. The third strain gauge is electrically connected to the second strain gauge, the zero-point compensation gauge, and the sensitivity temperature compensation gauge, respectively. The fourth strain gauge is electrically connected to the zero-point compensation gauge, the second terminal, and the first strain gauge, respectively. The zero-point temperature compensation piece and the zero-point compensation piece are respectively electrically connected to the first terminal block.

2. The tension / compression sensor with compensation function according to claim 1, characterized in that, The first heat insulation layer is made of heat insulation adhesive; The first heat insulation layer includes a first adhesive layer and a second adhesive layer; At the location of the strain gauge, the first adhesive layer is located between the elastomer and the strain gauge, the strain gauge is bonded to the elastomer through the first adhesive layer, the outline of the strain gauge is located within the outline of the first adhesive layer, and the second adhesive layer covers the strain gauge and the first adhesive layer. At the location of the compensation piece, the first adhesive layer is located between the elastomer and the compensation piece, the compensation piece is bonded to the elastomer through the first adhesive layer, the outline of the compensation piece is located within the outline of the first adhesive layer, and the second adhesive layer covers the compensation piece and the second adhesive layer.

3. The tension / compression sensor with compensation function according to claim 2, characterized in that, The connection points of the strain gauge to the high-temperature resistant cable, the connection points of the compensation plate to the high-temperature resistant cable, and the connection points of the terminal block to the high-temperature resistant cable are respectively welded with high-temperature solder and are respectively covered by the first heat insulation layer. Each solder joint formed by the high-temperature solder is covered by the first heat insulation layer.

4. The tension / compression sensor with compensation function according to claim 3, characterized in that, The elastic body is provided with a wire hole and a stranded wire. One end of the stranded wire passes through the wire hole along the direction from the inside to the outside of the elastic body. The stranded wire located outside the wire hole is electrically connected to the terminal. The connection between the stranded wire and the terminal is welded with the high-temperature solder. The connection points of the terminal block to the high-temperature resistant cable, the connection points of the terminal block to the stranded wire, and the wire passage holes are all covered by high-temperature silicone rubber, wherein the high-temperature silicone rubber is located outside the first heat insulation layer.

5. The tension / compression sensor with compensation function according to claim 4, characterized in that, It also includes the casing; The number of housings is two, and the two housings are defined as the first housing and the second housing, respectively. The two housings are used to cover at least the strain gauge, the compensation plate, the wiring terminal, the first heat insulation layer and a portion of the elastomer, and the two housings form gaps with the elastomer. The two housings are wrapped with the protective layer, which is specifically an adhesive tape made of polyimide material.

6. The tension / compression sensor with compensation function according to claim 5, characterized in that, The first mounting surface and the second mounting surface are both planes, and the first mounting surface and the second mounting surface are arranged back to back; On the first mounting surface, the length direction of the first strain gauge is parallel to the axial direction of the elastic body, the length direction of the second strain gauge is perpendicular to the axial direction of the elastic body, and on the second mounting surface, the length direction of the third strain gauge is parallel to the axial direction of the elastic body, and the length direction of the fourth strain gauge is perpendicular to the axial direction. The third mounting surface and the first mounting surface are respectively located on the same side of the elastomer, the fourth mounting surface and the second mounting surface are respectively located on the same side of the elastomer, and the fifth mounting surface is located on a portion of the surface of the elastomer between the first mounting surface and the second mounting surface; The sixth mounting surface and the seventh mounting surface are opposite to each other, and the third mounting surface, the sixth mounting surface, the fourth mounting surface and the seventh mounting surface surround the elastic body in a sequentially spaced manner; The number of wire-passing holes is two, and the two wire-passing holes are defined as the first wire-passing hole and the second wire-passing hole, respectively. The first wire-passing hole is recessed in the sixth mounting surface, and the second wire-passing hole is recessed in the seventh mounting surface. The first housing and the second housing together cover the first mounting surface to the seventh mounting surface.

7. The tension / compression sensor with compensation function according to claim 6, characterized in that, The first connecting segment and the second connecting segment are respectively machined with external threads; The elastomer is also provided with an installation channel, which forms an opening with each of the two ends of the elastomer. The connection positions of the installation channel with the first wire hole and the second wire hole are located within the elastomer. One section of the stranded wire is confined within the mounting channel.

8. The tension / compression sensor with compensation function according to any one of claims 1 to 7, characterized in that, The elastomer is restricted to a load capacity of -20,000 pounds to +20,000 pounds, wherein the elastomer is restricted to be made of stainless steel 17-4PH with a hardness between HRC44 and HRC48, and when the elastomer receives a force in the range of zero pounds to +20,000 pounds, the force on the elastomer is tensile, and when the elastomer receives a force in the range of zero pounds to -20,000 pounds, the force on the elastomer is compressive.

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