Device and method for pasting strain gauge of force sensor

Abstract

The invention provides a device and method for pasting a strain gauge of a force sensor, and relates to the technical field of sensor design, and the device comprises a positioning assembly which is used for positioning the pasting position of a to-be-installed strain gauge; and the force application assembly is matched with the positioning assembly to work and applies pressure required by high-temperature curing to the strain gauge to be installed. Components of the device are simple and reasonable in design, adopted structural materials are common and easy to process, and selected auxiliary materials are wide in market application and convenient to purchase. The pressure is adjustable and stable, the height is adjustable, the device is suitable for various types of products, the curing time is greatly shortened, the scrap amount of the strain gauges in the pasting and pressure maintaining process is reduced, the quality stability of the products is guaranteed, and the purposes of energy conservation, consumption reduction and efficient production are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of sensor design, and in particular provides a device and a method for pasting strain gauges of force sensors. Background Art

[0002] Strain gauge pasting technology is an indispensable and important process in sensor manufacturing, and has a vital impact on the measurement accuracy, performance and practical application of the sensor. The existing tooling used for pasting strain gauges of tension and pressure sensors mainly adopts semicircular clamps to position and paste by tightening nuts and screws. The operation is difficult, and the pasting position is basically entirely manual. High-precision positioning cannot be guaranteed after pasting, and the force is unstable, which can easily damage the strain gauge and cause it to be scrapped. Only two opposite strain gauges can be pasted at one time, and the high-temperature curing time is 6 hours. Four strain gauges are required to form a Wheatstone bridge, and the total curing time for a set of products is 12 hours. The existing technology has the disadvantages of time-consuming, consumables, equipment consumption, low precision, and poor operability. Summary of the invention

[0003] The purpose of the present application is to solve the shortcomings of the prior art such as time consumption, material consumption, and equipment consumption, and to propose a strain gauge pasting device and method for a force sensor.

[0004] In order to achieve the above-mentioned object, the present invention adopts the following technical solution: a device for pasting strain gauges of force sensors, used to install the strain gauges in the elastic body of the force sensor, the device comprising:

[0005] Positioning assembly, used to locate the pasting position of the strain gauge to be installed;

[0006] The force-applying component cooperates with the positioning component to apply the pressure required for high-temperature curing to the strain gauge to be installed.

[0007] The device for pasting strain gauges of force sensors provided by the present invention also has the following technical features: the positioning assembly is provided with a positioning base.

[0008] The positioning base includes a positioning base plate and a positioning base body which is integrally arranged with the positioning base plate.

[0009] The positioning bottom plate is provided with a positioning plane, and the positioning plane is aligned with the side plane of the elastic body.

[0010] The positioning base extends into the cylindrical hole of the elastic body, and the positioning base is provided with a plurality of positioning grooves.

[0011] The positioning assembly also includes a pressing block matched with the groove, and the outer arc surface of the pressing block is used for pasting the strain gauge.

[0012] The device for pasting strain gauges of force sensors provided by the present invention also has the following technical features: the positioning assembly is also provided with an adjustment gasket, which is arranged between the positioning base plate and the elastomer and is used to adjust the depth of the positioning base extending into the elastomer.

[0013] The device for pasting strain gauges of force sensors provided by the present invention also has the following technical features: the pressing block is made of hard rubber, and a centering and alignment cross line is engraved on the outer arc surface of the pressing block.

[0014] The device for pasting strain gauges of force sensors provided by the present invention also has the following technical feature: the strain gauge is bonded to the pressing block using double-sided tape, and the failure temperature of the double-sided tape is not higher than the high-temperature curing temperature of the special adhesive for pasting the strain gauge.

[0015] The device for pasting strain gauges of force sensors provided by the present invention also has the following technical features: the force-applying assembly includes a support rod cooperating with the positioning assembly, a double-headed screw passing through a positioning base plate in the positioning assembly, a connecting block for mounting the support rod to one end of the double-headed screw, a nut arranged at the other end of the double-headed screw, and an elastic gasket and a flat gasket arranged between the nut and the bottom surface of the positioning base plate.

[0016] The device for pasting strain gauges of force sensors provided by the present invention also has the following technical features: the positioning assembly includes a pressure block that cooperates with the support rod, the pressure block and the support rod are connected by a separate ball joint, a spherical surface is provided at one end of the support rod, and the pressure block is provided with a spherical groove that cooperates with the spherical surface.

[0017] The device for pasting strain gauges of force sensors provided by the present invention also has the following technical feature: the support rod is connected to the connecting block by rivets.

[0018] Another object of the present invention is to provide a method for pasting a strain gauge of a force sensor, the method using the device as described in any one of the above items, comprising:

[0019] Place the positioning base in the cylindrical hole of the elastic body, and adjust the position of the positioning base plate so that the positioning plane of the positioning base plate is aligned with the side surface of the elastic body;

[0020] Adjust the adjusting gasket so that the insertion depth of the positioning base meets the requirements;

[0021] Paste the strain gauge to the outer curved surface of the pressing block;

[0022] Apply special glue for strain gauge pasting to the reserved strain gauge position in the cylindrical hole of the elastic body;

[0023] Placing the pressing block in the positioning groove of the positioning base;

[0024] Pass the double-headed screw of the force-applying assembly through the center hole of the positioning base plate to make the support rod fit with the pressure block;

[0025] Use a torque wrench to apply force to the nut at the other end of the double-headed screw to transfer the force to the support rod. The support rod applies force to the surface of the strain gauge through the pressure block, so that the strain gauge is attached to the corresponding position in the cylindrical hole of the elastomer;

[0026] High temperature curing makes the double-sided adhesive ineffective and the special adhesive for strain gauges solidifies;

[0027] After high-temperature curing is completed, remove the force-applying component first, then remove the positioning component to complete the pasting.

[0028] Beneficial Effects

[0029] The device for pasting strain gauges of force sensors proposed in the present invention has a simple and reasonable design of components, common structural materials, easy processing, and a wide range of auxiliary materials in the market, which are easy to purchase. The pressure is adjustable and the pressure is stable, the height is adjustable, and it is suitable for various products, and the curing time is greatly reduced, and the scrapping amount of strain gauges during the pasting and pressure-maintaining process is reduced, so as to ensure the stability of product quality and achieve the purpose of energy saving and consumption reduction and efficient production.

[0030] The method for pasting strain gauges of force sensors proposed in the present invention eliminates the influence of manual operation during pasting, ensures accurate positioning during the pasting process, and has a simple and convenient operation method, adjustable pressure, stable pressure maintenance, adjustable height, and adaptability to various types of products. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 A schematic cross-sectional view of the structure of the device for pasting strain gauges of force sensors provided by the present invention;

[0033] Figure 2 A schematic diagram of the structure of the device for pasting strain gauges of force sensors provided by the present invention;

[0034] Figure 3 It is a schematic diagram of the strain gauge being pasted on the pressing plate in an embodiment of the present invention;

[0035] Figure 4 It is a structural schematic diagram of a positioning component in an embodiment of the present invention;

[0036] Figure 5is a schematic structural diagram of a force-applying component in an embodiment of the present invention,

[0037] Among them, 1: elastic body; 2: pressure block; 3: support rod; 4: connecting block; 5: rivet; 6: adjustment gasket; 7: double-headed screw; 8: nut; 9: elastic gasket; 10: flat gasket; 11: positioning base; 12: strain gauge. DETAILED DESCRIPTION

[0038] The present application is further described in detail below in conjunction with the accompanying drawings and examples, but it should be noted that these implementation methods are not limitations of the present application, and equivalent changes or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these implementation methods are all within the scope of protection of the present application.

[0039] In the description of the embodiments of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the creation of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the creation of the present application.

[0040] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0041] The terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention of this application can be understood by specific circumstances.

[0042] like Figure 1-5 As shown, an embodiment of the present application provides a device for pasting a strain gauge of a force sensor, which is used to install the strain gauge 12 in the elastic body 1 of the force sensor, and the device includes:

[0043] Positioning assembly, used to locate the pasting position of the strain gauge to be installed;

[0044] The force-applying component cooperates with the positioning component to apply the pressure required for high-temperature curing to the strain gauge to be installed.

[0045] In some embodiments, the positioning assembly is provided with a positioning base 11.

[0046] The positioning base 11 includes a positioning base plate and a positioning base body which is integrated with the positioning base plate.

[0047] The positioning bottom plate is provided with a positioning plane, and the positioning plane is aligned with the side plane of the elastic body 1.

[0048] The positioning base extends into the cylindrical hole of the elastic body 1, and the positioning base is provided with a plurality of positioning grooves.

[0049] The positioning assembly further comprises a pressing block 2 matched with the groove, and the outer arc surface of the pressing block 2 is used for pasting the strain gauge 12 .

[0050] In some embodiments, the positioning assembly is further provided with an adjustment gasket 6, which is disposed between the positioning base plate and the elastic body 1 and is used to adjust the depth of the positioning base extending into the elastic body 1. Selecting an appropriate adjustment gasket 6 can adjust the pasting position of the strain gauge 12 to adapt to various types of sensor strain gauges.

[0051] In some embodiments, the pressing block 2 is made of hard rubber, and a centering and alignment cross line is engraved on the outer arc surface of the pressing block 2. Except for the pressing block 2, all other structures are made of metal materials. Since the curing pressure of the special glue for sticking the strain gauge is relatively small, it can prevent the strain gauge 12 from being deformed after being subjected to force and prevent the strain gauge 12 from being damaged by pressure. The centering and alignment cross line serves as a positioning reference for sticking the strain gauge 12 on the pressing block 2.

[0052] In some embodiments, the strain gauge 12 is bonded to the pressing block 2 by using double-sided adhesive, and the failure temperature of the double-sided adhesive is not higher than the high temperature curing temperature of the special adhesive for bonding the strain gauge.

[0053] In the above embodiment, the double-sided adhesive used is GPL-060 multifunctional double-sided adhesive, which has the characteristics of becoming ineffective at high temperatures above +110°C, leaving no traces when disassembled, and facilitating the separation of the strain gauge 12 and the pressing block 2.

[0054] In some embodiments, the force-applying assembly includes a support rod 3 cooperating with the positioning assembly, a double-headed screw rod 7 passing through a positioning base plate in the positioning assembly, a connecting block 4 for mounting the support rod 3 to one end of the double-headed screw rod 7, a nut 9 arranged at the other end of the double-headed screw rod 7, and an elastic gasket 9 and a flat gasket 10 arranged between the nut 8 and the bottom surface of the positioning base plate.

[0055] In the above embodiment, the nut 8 is tightened by applying force with a torque wrench to ensure that the pressure required for the strain gauge 12 to be glued and cured is reached, which can be applicable to the pressure-maintaining and curing of various strain gauge glues.

[0056] In some embodiments, the positioning assembly includes a pressure block 2 that cooperates with the support rod 3. The pressure block 2 and the support rod 3 are connected by a separate ball joint. A spherical surface is provided at one end of the support rod 3, and the pressure block 2 is provided with a spherical groove that cooperates with the spherical surface.

[0057] In some embodiments, the support rod 3 and the connecting block 4 are connected via rivets 5 .

[0058] In some embodiments, a method for pasting a strain gauge of a force sensor is provided, wherein the method uses the device described in any of the above embodiments, and comprises:

[0059] Place the positioning base in the cylindrical hole of the elastic body 1, and adjust the position of the positioning base plate so that the positioning plane of the positioning base plate is aligned with the side surface of the elastic body 1;

[0060] Adjust the adjusting gasket 6 so that the insertion depth of the positioning base meets the requirements;

[0061] Paste the strain gauge 12 to the outer arc surface of the pressing block 2;

[0062] Apply special glue for strain gauge pasting to the reserved strain gauge position in the cylindrical hole of elastic body 1;

[0063] Place the pressing block 2 in the positioning groove of the positioning base;

[0064] Pass the double-headed screw rod 7 of the force-applying assembly through the central hole of the positioning base plate to make the support rod 3 fit with the pressing block 2;

[0065] Use a torque wrench to apply force to the nut 8 at the other end of the double-headed screw 7 to transfer the force to the support rod 3. The support rod 3 applies force to the surface of the strain gauge 12 through the pressure block 2, so that the strain gauge 12 is attached to the corresponding position in the cylindrical hole of the elastic body 1;

[0066] High temperature curing makes the double-sided adhesive ineffective and the special adhesive for strain gauges solidifies;

[0067] After high-temperature curing is completed, remove the force-applying component first, then remove the positioning component to complete the pasting.

[0068] In the above embodiment, the special glue for strain gauge pasting is H-610 high-performance two-component epoxy resin adhesive, which has a long-term applicable temperature of -226℃~+200℃ and a short-term applicable temperature of -226℃~+300℃. The curing method is pressurized high-temperature curing. During the curing, the temperature is raised to 135℃ at 2℃ / min, kept at this temperature for 2h, and then the pressure is released after cooling to room temperature in the oven. The temperature is raised to 165℃ at 2℃ / min, kept at this temperature for 2h, and then cooled to room temperature in the oven.

[0069] The above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A device for pasting strain gauges of force sensors, used for installing strain gauges in elastic bodies of force sensors, characterized in that: The device comprises: Positioning assembly, used to locate the pasting position of the strain gauge to be installed; The force-applying component cooperates with the positioning component to apply the pressure required for high-temperature curing to the strain gauge to be installed.

2. The device for bonding strain gauges of force sensors according to claim 1, characterized in that: The positioning assembly is provided with a positioning base. The positioning base includes a positioning base plate and a positioning base body which is integrally arranged with the positioning base plate. The positioning bottom plate is provided with a positioning plane, and the positioning plane is aligned with the side plane of the elastic body. The positioning base extends into the cylindrical hole of the elastic body, and the positioning base is provided with a plurality of positioning grooves. The positioning assembly also includes a pressing block matched with the groove, and the outer arc surface of the pressing block is used for pasting the strain gauge.

3. The device for bonding strain gauges of force sensors according to claim 2, characterized in that: The positioning assembly is further provided with an adjusting gasket, which is arranged between the positioning base plate and the elastic body and is used to adjust the depth of the positioning base extending into the elastic body.

4. The device for bonding strain gauges of force sensors according to claim 2, characterized in that: The pressing block is made of hard rubber, and a centering and alignment cross line is engraved on the outer arc surface of the pressing block.

5. The device for bonding strain gauges of force sensors according to claim 2, characterized in that: The strain gauge is bonded to the pressing block by using double-sided adhesive, and the failure temperature of the double-sided adhesive is not higher than the high temperature curing temperature of the special adhesive for bonding the strain gauge.

6. The device for bonding strain gauges of force sensors according to claim 1, characterized in that: The force-applying assembly includes a support rod cooperating with the positioning assembly, a double-headed screw passing through a positioning base plate in the positioning assembly, a connecting block for mounting the support rod to one end of the double-headed screw, a nut arranged at the other end of the double-headed screw, and an elastic gasket and a flat gasket arranged between the nut and the bottom surface of the positioning base plate.

7. The device for bonding strain gauges of force sensors according to claim 6, characterized in that: The positioning assembly comprises a pressing block matched with the support rod, the pressing block and the support rod are connected by a separate ball joint, one end of the support rod is provided with a spherical surface, and the pressing block is provided with a spherical groove matched with the spherical surface.

8. The device for bonding strain gauges of force sensors according to claim 6, characterized in that: The support rod is connected to the connecting block through rivets.

9. A method for pasting a strain gauge of a force sensor, characterized in that: The method adopts the device according to any one of claims 1 to 8, comprising: Place the positioning base in the cylindrical hole of the elastic body, and adjust the position of the positioning base plate so that the positioning plane of the positioning base plate is aligned with the side surface of the elastic body; Adjust the adjusting gasket so that the insertion depth of the positioning base meets the requirements; Paste the strain gauge to the outer curved surface of the pressing block; Apply special glue for strain gauge pasting to the reserved strain gauge position in the cylindrical hole of the elastic body; Placing the pressing block in the positioning groove of the positioning base; Pass the double-headed screw of the force-applying assembly through the center hole of the positioning base plate to make the support rod fit with the pressure block; Use a torque wrench to apply force to the nut at the other end of the double-headed screw to transfer the force to the support rod. The support rod applies force to the surface of the strain gauge through the pressure block, so that the strain gauge is attached to the corresponding position in the cylindrical hole of the elastomer; High temperature curing makes the double-sided adhesive ineffective and the special adhesive for strain gauges solidifies; After high-temperature curing is completed, remove the force-applying component first, then remove the positioning component to complete the pasting.

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