Force transducer used in high-low-temperature high-pressure silicone oil environment

Abstract

The invention relates to the field of force transducers, and discloses a force transducer used in a high-low-temperature high-pressure silicone oil environment, which comprises an elastic body, the left end of the elastic body is detachably connected with a connecting piece I, the right end of the elastic body is detachably connected with a connecting piece II, and the inner wall of the connecting piece II is provided with a reserved channel. A high-temperature strain gauge is installed on the inner wall of the elastic body, a cable is installed on the side, close to the center line of the elastic body, of the high-temperature strain gauge, the cable penetrates through the second connecting piece through a reserved channel, the inner wall of the elastic body is filled with silicon dioxide, and the first connecting piece is connected with the rear end of the elastic body through internal threads. According to the invention, a completely closed structural design is adopted, the interior of the elastic body cavity is filled with silicon dioxide sand grains, and the silicon dioxide sand grains have good expansion coefficient and flexibility under the working conditions of high temperature and low temperature cross change and high pressure, so that the temperature difference and the pressure difference in the elastic body cavity can be automatically balanced.

Description

Technical Field

[0001] The invention relates to the field of force sensors, and in particular to a force sensor used in a high-low-temperature and high-pressure silicone oil environment. Background Art

[0002] In the aerospace, nuclear power and other industrial fields, some core components are domestically produced. These components generally operate in special environments with high and low temperature cross-changes and high pressure. The service life, use environment and reliability of the parts need to be tested under simulated conditions in a simulated environment to ensure the safety of operation in the aerospace, nuclear power and other industrial fields.

[0003] For reference, Chinese patent with Chinese patent publication number CN115876368A discloses a force sensor for high temperature and high pressure water environment and its assembly method, which adopts a five-layer sealing ring method for sealing. The cavity is filled with hydraulic oil. The piston reciprocates under the push of the hydraulic oil to balance the pressure inside and outside the sealing cavity.

[0004] This will cause the strain gauge on the inner wall of the elastomer to be in complete contact with the hydraulic oil. The strain gauge is bonded to the inner wall with special glue. Since the hydraulic oil is corrosive, the glue will fail under long-term operation, and the strain gauge will fall off, making the sensor unusable. At the same time, long-term use of the sealing ring under high and low temperature cross-changes and high-pressure environments will also cause the sealing ring to wear and age. Once hydraulic oil leakage occurs, it will contaminate the medium in the kettle, and the inner cavity of the kettle needs to be cleaned and washed again, which brings inconvenience to the experimenter. At the same time, since the sensor is sealed by a sealing ring, it still cannot separate the friction force of the sample and the friction force generated between the seal and the moving axis, which will cause the measurement accuracy of the overall device to decrease. For this reason, a force sensor for high, low temperature and high-pressure silicone oil environment is proposed to solve the above problems. Summary of the invention

[0005] In order to make up for the above deficiencies, the present invention provides a force sensor for use in high-temperature and high-pressure silicone oil environments, aiming to improve the problem in the prior art that "the prior art fails to separate the friction force of the sample and the friction force generated between the seal and the moving shaft, which will lead to a decrease in the measurement accuracy of the overall device."

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a force sensor for use in a high-temperature, low-pressure and silicone oil environment, comprising an elastomer, the left end of the elastomer being detachably connected to a connector one, the right end of the elastomer being detachably connected to a connector two, the inner wall of the connector two being provided with a reserved channel, a high-temperature strain gauge being installed on the inner wall of the elastomer, a cable being installed on the side of the high-temperature strain gauge close to the center line of the elastomer, the cable passing through the connector two through the reserved channel, and the inner wall of the elastomer being filled with silica.

[0007] As a further description of the above technical solution: The first connecting piece is connected to the rear end of the elastic body through an internal thread, and the second connecting piece is connected to the front end of the elastic body through an internal thread.

[0008] As a further description of the above technical solution: The ends of the first connecting member and the second connecting member close to the center of the elastic body are both configured to be conical.

[0009] As a further description of the above technical solution: Concave grooves are arranged at both left and right ends of the inner wall of the elastomer; an O-ring 1 is installed at the connection between the inner wall of the elastomer and the right surface of the first connector; and an O-ring 2 is installed at the connection between the inner wall of the elastomer and the left surface of the second connector.

[0010] As a further description of the above technical solution: The high temperature strain gauges are provided in a plurality of groups, and the plurality of groups of high temperature strain gauges are arranged in a rotation array with the center line of the elastic body as the rotation axis.

[0011] As a further description of the above technical solution: A cold welding seam is arranged at the connection between the outer wall of the elastic body and the second connecting piece.

[0012] As a further description of the above technical solution: The cold welding seams are arranged in two groups, wherein one group of the cold welding seams is arranged at the connection between the first connector and the elastic body.

[0013] The present invention has the following beneficial effects: 1. In the present invention, a completely closed structure design is adopted, and silica sand is filled inside the elastomer cavity. The silica sand has a good expansion coefficient and flexibility under high and low temperature cross-change and high pressure conditions, and can automatically balance the temperature difference and pressure difference in the elastomer cavity, thereby eliminating the friction generated between the seal and the moving shaft, and ensuring the accuracy of the measurement data.

[0014] 2. In the present invention, the overall device adopts a completely closed structural design, so that the overall device has good pressure resistance and can work in a high-pressure environment. In this way, force measurement operations can be performed in the autoclave body, and the overall device has good applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the three-dimensional structure of the overall device of the present invention; Figure 2 It is a schematic cross-sectional view of the three-dimensional structure of the overall device in the present invention.

[0016] Legend: 1. Connector 1; 2. Elastomer; 3. Cold welding seam; 4. Connector 2; 5. Cable; 6. O-ring 1; 7. High temperature strain gauge; 8. O-ring 2; 9. Silicon dioxide. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Reference Figure 1 and Figure 2 An embodiment of the present invention is a force sensor for use in a high-low-temperature and high-pressure silicone oil environment, comprising an elastic body 2 for supporting the overall device, the elastic body 2 being processed from a thin-walled tube, having high rigidity, and being able to undergo recoverable elastic deformation when subjected to force, and at the same time being able to convert force into its own deformation, the left end of the elastic body 2 being detachably connected with a connector 1, the right end of the elastic body 2 being detachably connected with a connector 2 4, the connector 1 1 and the connector 2 4 being able to respectively seal the two ends of the elastic body 2, the inner wall of the connector 2 4 being provided with a reserved channel for the line to pass through, the inner wall of the elastic body 2 being provided with a high-temperature strain gauge 7, the elastic body 2 and the high-temperature strain gauge 7 A full-bridge circuit can be formed between them. When the elastic body 2 is deformed by force, the resistance of the high-temperature strain gauge 7 will change accordingly, converting the change in force into a change in resistance. The full-bridge circuit then converts the change in resistance into an electrical signal to achieve the electrical signal output of the force value. A cable 5 for transmitting signals is installed on the side of the high-temperature strain gauge 7 close to the center line of the elastomer 2. The cable 5 passes through the connector 2 4 through a reserved channel. The inner wall of the elastomer 2 is filled with silicon dioxide 9. The silicon dioxide 9 sand has a good expansion coefficient and flexibility. It can automatically balance the temperature difference and pressure difference in the cavity of the elastomer 2 with the help of its own deformation, thereby avoiding the impact of environmental changes on the internal structure of the sensor and the measurement accuracy.

[0019] Reference Figure 1 and Figure 2, the connector 1 is connected to the rear end of the elastic body 2 through an internal thread, and the connector 2 4 is connected to the front end of the elastic body 2 through an internal thread. The connector 1 and the connector 2 4 can form a preliminary connection with the elastic body 2 through the internal thread. The ends of the connector 1 and the connector 2 4 close to the center of the elastomer 2 are both set to a cone. By adopting a conical design, the silicon dioxide 9 can be guided to completely fill the cavity of the elastomer 2 to ensure the filling effect. Concave grooves are set at both ends of the inner wall of the elastomer 2. An O-ring 1 6 is installed at the connection between the inner wall of the elastomer 2 and the right surface of the connector 1, and an O-ring 2 8 is installed at the connection between the inner wall of the elastomer 2 and the left surface of the connector 2 4. The O-ring 1 6 and the O-ring 2 8 can be used to preliminarily block the liquid from entering the interior of the device. A plurality of groups of high-temperature strain gauges 7 are provided, and the plurality of groups of high-temperature strain gauges 7 are arranged in a rotating array with the center line of the elastomer 2 as the rotation axis.

[0020] Reference Figure 1 and Figure 2 A cold welding seam 3 is provided at the connection between the outer wall of the elastomer 2 and the connector 2 4 to facilitate subsequent welding. Two groups of cold welding seams 3 are provided, and one group of cold welding seams 3 is provided at the connection between the connector 1 and the elastomer 2. When the connector 1 and the connector 2 4 are installed, the connection between the connector 1, the connector 2 4 and the elastomer 2 can be reinforced with the help of welding technology to enhance the connection strength, improve the overall sealing, prevent the leakage of high-pressure silicone oil, and ensure the normal operation of the sensor in harsh environments.

[0021] Working principle: Before measuring, it is necessary to evenly apply an appropriate amount of special adhesive on the strain measurement area of ​​the inner wall of the elastomer 2, and then paste multiple sets of high-temperature strain gauges 7 at the designated positions. During the pasting process, it is necessary to ensure that the high-temperature strain gauges 7 are firmly and smoothly pasted without bubbles and wrinkles to avoid affecting the performance and measurement accuracy of the high-temperature strain gauges 7. After pasting, the high-temperature strain gauges 7 are connected to form a full-bridge circuit in accordance with the circuit connection requirements, and ensure that the connection is reliable. Then, the O-ring 1 6 and the O-ring 2 8 can be installed in the concave grooves at the left and right ends of the inner wall of the elastomer 2 respectively. During installation, carefully check the integrity of the sealing ring to ensure that there is no damage, aging, etc., and press the sealing ring slowly and evenly into the concave groove so that it is completely embedded in the groove without twisting or flipping, to ensure a good sealing effect and initially block the liquid from entering the device.

[0022] After the internal device of the elastomer 2 is installed, the external thread of the connector 2 4 can be aligned with the internal thread of the front end of the elastomer 2, and the connector 2 4 can be slowly rotated to make it preliminarily connected with the elastomer 2, and then the silicon dioxide 9 can be poured from the opening at the rear end of the elastomer 2, and the amount of pouring should be 2 / 3 of the distance from the rear end face of the elastomer 2. Then, align the internal thread of the connector 1 with the internal thread at the rear end of the elastomer 2, rotate the connector 1 and tighten it. During the tightening process, the conical end of the connector 1 and the connector 2 4 close to the center of the elastomer 2 is used to guide the silicon dioxide 9 to completely fill the cavity of the elastomer 2, ensuring that the filling is uniform and dense, and then the cold welding equipment can be used to weld and reinforce the connection between the connector 1 and the elastomer 2, and the connection between the connector 2 4 and the elastomer 2, so as to ensure the connection strength of the overall device, improve the overall sealing, and prevent the leakage of high-pressure silicone oil.

[0023] When measuring, the overall device can use the good expansion coefficient and flexibility of silicon dioxide 9 to automatically balance the temperature difference and pressure difference in the chamber of the elastomer 2, thereby eliminating the friction generated between the seal and the moving shaft to ensure the accuracy of the measurement data.

[0024] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A force sensor for use in a high-low-temperature and high-pressure silicone oil environment, comprising an elastic body (2), characterized in that: The left end of the elastic body (2) is detachably connected to a connecting piece 1 (1), and the right end of the elastic body (2) is detachably connected to a connecting piece 2 (4), the inner wall of the connecting piece 2 (4) is provided with a reserved channel, a high-temperature strain gauge (7) is installed on the inner wall of the elastic body (2), a cable (5) is installed on the side of the high-temperature strain gauge (7) close to the center line of the elastic body (2), and the cable (5) passes through the connecting piece 2 (4) through the reserved channel, and the inner wall of the elastic body (2) is filled with silicon dioxide (9).

2. A force sensor for use in a high-low-temperature and high-pressure silicone oil environment according to claim 1, characterized in that: The first connecting piece (1) is connected to the rear end of the elastic body (2) via an internal thread, and the second connecting piece (4) is connected to the front end of the elastic body (2) via an internal thread.

3. The force sensor for use in a high-low-temperature and high-pressure silicone oil environment according to claim 1, characterized in that: The ends of the connecting piece 1 (1) and the connecting piece 2 (4) close to the center of the elastic body (2) are both arranged in a conical shape.

4. The force sensor for use in a high-low-temperature and high-pressure silicone oil environment according to claim 1, characterized in that: The inner wall of the elastic body (2) is provided with concave grooves at both ends, an O-ring 1 (6) is installed at the connection between the inner wall of the elastic body (2) and the right surface of the first connecting piece (1), and an O-ring 2 (8) is installed at the connection between the inner wall of the elastic body (2) and the left surface of the second connecting piece (4).

5. The force sensor for use in a high-low-temperature and high-pressure silicone oil environment according to claim 1, characterized in that: A plurality of groups of the high temperature strain gauges (7) are provided, and the plurality of groups of the high temperature strain gauges (7) are arranged in a rotation array with the center line of the elastic body (2) as the rotation axis.

6. The force sensor for use in a high-low-temperature and high-pressure silicone oil environment according to claim 1, characterized in that: A cold welding seam (3) is provided at the connection between the outer wall of the elastic body (2) and the second connecting piece (4).

7. A force sensor for use in a high-low-temperature and high-pressure silicone oil environment according to claim 6, characterized in that: Two groups of cold welding seams (3) are provided, wherein one group of cold welding seams (3) is provided at the connection between the first connecting piece (1) and the elastic body (2).

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