Micro-displacement sensor

Abstract

The utility model belongs to the technical field of displacement sensor equipment, and provides a micro displacement sensor, which comprises a plate-type elastomer, a pressing block, a bolt, an ejector rod and a strain gauge, the plate-type elastomer is arranged on the surface of a measured component, the strain gauge is adhered to the root of a thin steel plate of the plate-type elastomer, and one end of the ejector rod is fixed on the surface of the measured component. The pressing block is detachably connected with the other end of the ejector rod through a bolt, and the plate type elastomer thin steel plate is clamped between the pressing block arc face and the ejector rod arc face to be tightly attached. The device is composed of the resistance strain gauges and the strain elastic bodies, the elastic bodies are thin steel plate type elastic bodies, the resistance strain gauges are pasted on the root portions of the steel plates so that deformation of the steel plates can be sensed more sensitively, a component differential motion full bridge can be installed on the deformed steel plates according to needs, and linearity errors are greatly eliminated. The device is low in installation damage failure rate, compact in overall structure, low in cost and high in precision.

Description

Technical Field

[0001] The utility model belongs to the technical field of displacement sensor equipment, in particular to a micro displacement sensor. Background Art

[0002] As a sensor for measuring tiny displacements, micro-displacement sensors can not only measure surface strain and cracks of components, but also measure the deflection of components. They are widely used in various industrial pressure measurement environments, involving many industries such as civil engineering, aviation, aerospace, petrochemicals, electric power, and shipbuilding. As a micro-displacement sensor, it can also be used as a strain sensor. Commonly used strain gauges include vibrating wire strain gauges and resistance strain gauges.

[0003] However, vibrating wire strain gauges are greatly affected by temperature and have high requirements for the installation environment. Resistance strain gauges are small in size, easily damaged, and have high requirements for the pasting process. When used in engineering, they are often difficult to install in the open air on site, difficult to treat the surface of the measured object, difficult to protect on site, and other unfavorable factors, resulting in poor pasting quality of resistance strain gauges, low measurement accuracy, high sensor damage rate, high installation cost, and are not suitable for harsh environments in engineering.

[0004] To this end, those skilled in the art have proposed a micro-displacement sensor to solve the problems raised in the background art. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides a micro-displacement sensor to solve the problems of poor installation and fixing effect, small application range, low measurement accuracy and the like in the prior art.

[0006] A micro-displacement sensor comprises a plate-type elastic body, a pressure block, a bolt, a push rod and a strain gauge.

[0007] Preferably, the plate-type elastic body is arranged on the surface of the component to be measured, and the strain gauge is adhered to the root of the thin steel plate of the plate-type elastic body.

[0008] Preferably, one end of the push rod is fixed to the surface of the component to be tested, the pressure block is detachably connected to the other end of the push rod by a bolt, and the plate-type elastomer thin steel plate is clamped tightly between the arc surface of the pressure block and the arc surface of the push rod.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] 1. The utility model is composed of a resistance strain gauge and a strain elastic body. The elastic body adopts a thin steel plate elastic body. The resistance strain gauge is pasted at the root of the steel plate to more sensitively sense the deformation of the steel plate. The steel plate elastic body adopted can design strain sensors with different sensitivities by changing the cross-sectional size of the steel plate, which can more specifically design strain sensor products with different sensitivities.

[0011] 2. The utility model micro-displacement sensor can arrange multiple sets of strain sensing devices in multiple directions on the surface of the component, and can measure the strain values ​​of the surface of the object being measured in multiple directions. Multiple sets can be repeatedly arranged for measurement, thereby making the strain sensor more sensitive and having higher measurement accuracy. The strain values ​​of other angles can be measured as needed, and are not limited to single-direction single-set measurement.

[0012] 3. The utility model can install a component differential full bridge on the deformed steel sheet as needed, that is, two resistance strain gauges are pasted on both sides of the steel sheet (the number of strain gauges can be increased as needed). Compared with the single bridge, the measurement scheme of constructing a differential full bridge can greatly eliminate linearity errors, and the sensitivity is 4 times that of a single bridge. It also has automatic compensation for temperature errors. Compared with the vibrating wire strain gauge, which is more affected by temperature, the measurement method adopted by the utility model patent is almost unaffected by temperature and can obtain higher measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the structure of the assembly of the present invention from a front view perspective;

[0014] Figure 2 This is a schematic diagram of the structure of the assembly of the present invention from a left perspective;

[0015] Figure 3 This is a schematic diagram of the structure of the assembly of the utility model from a top view;

[0016] Figure 4 This is a schematic diagram of the internal perspective structure of the assembly of the present invention.

[0017] In the picture:

[0018] 1. Plate-type elastic body; 2. Pressure block; 3. Bolt; 4. Push rod; 5. Strain gauge. DETAILED DESCRIPTION

[0019] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0020] As attached Figure 1 To the attached Figure 4 As shown:

[0021] Embodiment: The present invention provides a micro-displacement sensor, comprising a plate-type elastic body 1, a pressure block 2, a bolt 3, a push rod 4 and a strain gauge 5.

[0022] The plate-type elastic body 1 is arranged on the surface of the component to be measured, and the strain gauge 5 is pasted on the root of the thin steel plate of the plate-type elastic body 1.

[0023] One end of the push rod 4 is fixed to the surface of the component to be tested, and the pressure block 2 is detachably connected to the other end of the push rod 4 by the bolt 3, and the thin steel plate of the plate-type elastic body 1 is clamped tightly between the arc surface of the pressure block 2 and the arc surface of the push rod 4.

[0024] The strain sensing part of the plate-type elastic body 1 is a long thin steel plate, the base of which is welded to the component to be measured. A strain gauge 5 is pasted at the root of the elastic body steel plate near the base, which can sense pressure changes more sensitively.

[0025] The push rod 4 is an L-shaped part, one end of which is fixed to the tested component by welding. The other end is provided with two threaded holes, which is connected to the pressure block 2 by bolts 3, and the elastomer steel plate is tightly clamped by the arc surface of the end and the arc surface of the pressure block 2.

[0026] The device is composed of a resistance strain gauge 5 and a strain elastomer. The elastomer adopts a thin steel plate elastomer 1. The resistance strain gauge 5 is pasted at the root of the steel plate, which can more sensitively sense the deformation of the steel plate. The steel plate elastomer 1 can be used to design strain sensors with different sensitivities by changing the cross-sectional size of the steel plate, so that strain sensor products with different sensitivities can be designed more specifically.

[0027] A component differential full bridge can also be installed on the deformed steel sheet as needed, that is, two resistance strain gauges 5 are respectively pasted on both sides of the steel sheet (the number of strain gauges 5 can be increased as needed). Compared with a single bridge, the measurement scheme of constructing a differential full bridge can greatly eliminate linearity errors, and the sensitivity is 4 times that of a single bridge. At the same time, it also has automatic compensation for temperature errors. Compared with the vibrating wire strain gauge, which is more affected by temperature, the measurement method adopted by the utility model patent is almost not affected by temperature and can obtain higher measurement accuracy.

[0028] Working principle: Under the action of external force, the tested component undergoes elastic deformation, and its surface produces compressive strain or tensile strain along the axis of the tested component. As the tested component is deformed by force, the plate-type elastic body 1 thin steel plate and the push rod 4 welded on the surface of the tested component undergo slight deformation along with the tested component. When the tested component is compressed, the plate-type elastic body 1 steel plate and the push rod 4 deform toward the middle together. Since the stiffness of the push rod 4 is greater than that of the elastic body thin steel plate, the plate-type elastic body 1 thin steel plate deforms outward under the action of the arc surface of the end of the push rod 4. When the tested component is pulled, the plate-type elastic body 1 thin steel plate deforms inward under the action of the arc surface of the pressure block 2, thereby causing the resistance of the strain gauge 5 pasted at the root of the thin steel plate to change. This resistance change is proportional to the strain of the specimen. The strain gauge 5 is connected to the excitation circuit to convert the resistance change into an electrical signal change. The electrical signal change obtained by the acquisition circuit is used to obtain the strain of the plate-type elastic body 1, and thus the strain of the tested component is obtained.

[0029] The utility model provides a measurement mechanism and method for strain or micro-displacement. After obtaining the strain and the strain or micro-displacement of the measured object, other physical quantities such as but not limited to cracks and component deflection can be inferred through the physical properties of the measured object.

[0030] The utility model converts the surface strain of the measured component into the strain of the elastic thin steel plate, and then obtains the strain of the thin steel plate through the resistive strain gauge 5, thereby indirectly obtaining the strain of the surface of the measured component. The strain sensor can be made more sensitive by changing the cross-sectional size of the thin steel plate.

[0031] The micro-displacement sensor of the utility model can be fixed in a variety of ways, and a variety of flexible fixing methods can be selected according to the structural characteristics of the surface of the measured component, such as welding fixation to the measured object, fixing with bolts, fixing with strong special adhesives, etc.

[0032] Compared with a single resistance strain gauge 5, the utility model adopts a combination of a resistance strain gauge 5 and a strain elastic body, and the strain gauge 5 is pasted on the elastic steel plate. The elastic steel plate is manufactured by machining. The area on the steel plate surface where the strain gauge 5 is pasted can be carefully surface-treated and pasted with the strain gauge 5 in the processing plant, which greatly improves the pasting quality of the strain gauge 5, reduces the installation workload and processing difficulty of the strain gauge at the construction site, is more suitable for harsh installation environments in engineering, has a low installation damage failure rate, a compact overall structure, low cost, and high precision.

[0033] In this utility model, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, indirect connection through an intermediate medium, internal communication between two components, or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0034] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0035] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or 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 scope of protection of the present invention.

[0036] The embodiments of the present invention are provided for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A micro-displacement sensor, characterized in that: It comprises a plate-type elastic body (1), a pressure block (2), a bolt (3), a push rod (4) and a strain gauge (5); The plate-type elastic body (1) is arranged on the surface of the component to be measured, and the strain gauge (5) is adhered to the root of the thin steel plate of the plate-type elastic body (1); One end of the push rod (4) is fixed to the surface of the component to be tested, and the pressure block (2) is detachably connected to the other end of the push rod (4) via a bolt (3), and the thin steel plate of the plate-type elastic body (1) is clamped between the arc surface of the pressure block (2) and the arc surface of the push rod (4) to fit tightly.

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