A resistance strain gauge sensitive element for large deformation displacement meter

Abstract

The utility model relates to big deformation displacement meter technical field, concretely relates to a big deformation displacement meter is with resistance strain type sensing element, through optimizing the structure of elastic sensitive part, utilize first arc section and second arc section can carry on the buffer when being impacted in the elastic sensitive part test process, improve the elastic sensitive part shock resistance, anti -vibration ability and stability to improve the service life, big deformation displacement meter is with resistance strain type sensing element adopts the full -sealing structure, further reduces the influence of outside environment to test accuracy, the structure of resistance strain gauge is optimized, and the resistance strain gauge is arranged on the upper and lower sides of flat section and constitutes a full bridge circuit, ensures that the elastic sensitive part is forced, and the consistency of strain change is pulled, is pressed to the output consistency of pulling and pressing, increases, and through increasing zero setting grid, the zero point output performance of big deformation displacement meter can be compensated resistance strain type sensing element, reduces the influence of outside environment change to test accuracy.

Description

Technical Field

[0001] This utility model relates to the field of large deformation displacement meter technology, specifically to a resistance strain gauge sensitive element for a large deformation displacement meter. Background Technology

[0002] Displacement gauges are suitable for installation inside and on the surface of concrete structures or other material structures to test and monitor hazards such as deformation, stress, cracks, and fissure changes in structures, thereby protecting the safety of buildings and public facilities.

[0003] A conventional displacement gauge includes an elastic sensing element and a full-bridge resistance strain gauge. The elastic sensing element adopts an arc-shaped structure with flat ends for fixing the arc-shaped structure and a semi-circular arc shape in the middle. The full-bridge resistance strain gauge is attached to one side of the middle semi-circular arc structure.

[0004] The displacement gauges using existing elastic sensing elements have the following main problems in use: 1) The elastic sensing element is semi-circular and tall, making it impossible to manufacture a fully sealed structure; 2) Small measurement range, ranging from -3000 to 3000 microstrain; 3) Poor impact resistance, vibration resistance, and stability; 4) Poor consistency between tensile and compressive strain changes, with large differences in output in the tensile and compressive directions; 5) The accuracy of the test is greatly affected by the external environment, such as temperature, vibration and impact.

[0005] Therefore, it cannot meet the actual needs of practical use. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a resistance strain gauge sensitive element for a large deformation displacement meter.

[0007] The solution of this utility model to the above-mentioned technical problems is as follows: A resistance strain gauge sensing element for a large deformation displacement meter, characterized in that it comprises an elastic sensing element and a resistance strain gauge; The elastic sensing element includes a first connecting segment, a first arc segment, a straight segment, a second arc segment, and a second connecting segment connected in sequence; the resistance strain gauges are respectively disposed on the upper and lower sides of the straight segment, and the resistance strain gauges are disposed in the same direction as the straight segment.

[0008] Further specified, the central angle of the first arc segment is the same as that of the second arc segment, and both the first connecting segment and the second connecting segment are parallel to the straight segment; The first connecting segment and the second connecting segment are symmetrically arranged about the vertical axis of symmetry of the straight segment; the first arc segment and the second arc segment are symmetrically arranged about the vertical axis of symmetry of the straight segment.

[0009] Further specified, the length of the first connecting segment is the same as the length of the second connecting segment, and the outer diameter of the first arc segment is the same as the outer diameter of the second arc segment.

[0010] Further defined, the left and right sides of the straight segment are connected to the first arc segment and the second arc segment respectively through inclined segments, and the first connecting segment, the first arc segment, the second arc segment and the second connecting segment are all located above the straight segment.

[0011] Further specified, the angle between the inclined segment and the straight segment is 120° to 140°, the distance between the left end face of the first connecting segment and the right end face of the second connecting segment is 45mm to 80mm, the width of the inclined segment, the first connecting segment, the first arc segment, the straight segment, the second arc segment and the second connecting segment are the same and are all 4mm to 10mm; the distance between the top of the first arc segment and the bottom of the straight segment is 5mm to 15mm.

[0012] Further defined, the inclined segment, the first connecting segment, the first arc segment, the straight segment, the second arc segment, and the second connecting segment are an integral structure; the resistance strain gauge is attached to the upper and lower sides of the straight segment.

[0013] Further specified, the resistance strain gauge includes a first strain unit and a second strain unit; The first strain unit includes a first measuring grid, a first pad, a second pad, and a first zero-adjustment grid; the second strain unit includes a second measuring grid, a third pad, a fourth pad, and a second zero-adjustment grid. The first measuring gate is nested outside the second measuring gate and is arranged in the same direction as the second measuring gate. One end of the first measuring gate is connected to the first pad through the first zero-adjustment gate, and the other end of the first measuring gate is connected to the second pad. One end of the second measuring gate is connected to the third pad, and the other end of the second measuring gate is connected to the fourth pad through the second zero-adjustment gate. The resistance value of the first measuring grid is the same as that of the second measuring grid. The directions of the first zero-adjustment grid, the second zero-adjustment grid, the first measuring grid, and the second measuring grid are all the same. The first measuring grid and the second measuring grid are coaxially arranged.

[0014] Further specifying, the first strain unit further includes a third zero-adjustment gate, and the second strain unit further includes a fourth zero-adjustment gate; The third zero-adjustment gate is connected between the other end of the first measurement gate and the second pad; the fourth zero-adjustment gate is connected between one end of the second measurement gate and the third pad.

[0015] Furthermore, the directions of the first zero-adjustment gate, the second zero-adjustment gate, the third zero-adjustment gate, and the fourth zero-adjustment gate are all the same.

[0016] Further specified, the first pad and the second pad are located on the same side, and the third pad and the fourth pad are located on the same side.

[0017] The beneficial effects of this utility model are as follows: 1. This utility model optimizes the structure of the elastic sensing element, utilizing the first and second arc segments to buffer the impact when the elastic sensing element is subjected to impact during testing, thereby improving the elastic sensing element's impact resistance, vibration resistance, and stability, and thus extending its service life. At the same time, the resistance strain gauge sensing element for the large deformation displacement meter adopts a fully sealed structure, which can further reduce the influence of the external environment on the testing accuracy and meet the measurement requirements of micro-strain from -10000 to 10000.

[0018] 2. This utility model optimizes the structure of the resistance strain gauge and sets the resistance strain gauge on the upper and lower sides of the straight section to form a full-bridge circuit, ensuring the consistency of tensile and compressive strain changes when the elastic sensitive element is subjected to force, thus improving the consistency of tensile and compressive output. At the same time, by adding a zero-adjustment grid, the zero-point output performance of the resistance strain gauge sensitive element for large deformation displacement gauges can be compensated, reducing the impact of external environmental changes on test accuracy. Attached Figure Description

[0019] Figure 1 This is a structural diagram of the resistance strain gauge sensing element for the large deformation displacement meter of this utility model; Figure 2 This is a side view of the resistance strain gauge sensing element for the large deformation displacement meter of this utility model; Figure 3 This is a structural diagram of the resistance strain gauge with two zero-adjustment grids of this utility model; Figure 4 This is a structural diagram of the resistance strain gauge with four zero-adjustment grids of this utility model; Figure 5 This is a structural diagram of the resistance strain gauge on the same side as the solder pad of this utility model.

[0020] In the figure, 10-elastic sensing element; 11-first connecting section; 12-first arc-shaped section; 13-straight section; 14-second arc-shaped section; 15-second connecting section; 16-inclined section; 17-connecting hole; 20-resistance strain gauge; 30-first strain unit; 31-first measuring grid; 32-first pad; 33-second pad; 34-first zero-adjustment grid; 35-third zero-adjustment grid; 40-second strain unit; 41-second measuring grid; 42-third pad; 43-fourth pad; 44-second zero-adjustment grid; 45-fourth zero-adjustment grid. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0023] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0024] In the description of the embodiments of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0025] In the description of the embodiments of this utility model, it should be noted that if terms such as "upper," "lower," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, they are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the utility model. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] Example 1 refer to Figure 1 This embodiment provides a resistance strain gauge sensing element for a large deformation displacement meter, including an elastic sensing element 10 and a resistance strain gauge 20 disposed on the elastic sensing element 10.

[0027] Among them, the elastic sensitive element 10 is a one-piece structure, and the material can be stainless steel, which is formed by stamping or bending.

[0028] refer to Figure 2 The elastic sensing element 10 includes a first connecting section 11, a first arc-shaped section 12, a straight section 13, a second arc-shaped section 14, and a second connecting section 15 connected in sequence. The resistance strain gauge 20 is a half-bridge strain gauge, which is respectively set on the upper and lower sides of the straight section 13, so that the two resistance strain gauges 20 can form a full-bridge circuit through the leads. When the elastic sensing element 10 senses the displacement change, the resistance strain gauge 20 attached to the elastic sensing element 10 will deform accordingly. The deformation is converted into a differential electrical signal through the Wheatstone bridge, and the electrical signal is transmitted to the instrument through the cable to realize the detection function.

[0029] The first and second arc segments can buffer the impact when the elastic sensitive element is subjected to impact during the test, thereby improving the impact resistance, vibration resistance and stability of the elastic sensitive element and thus extending its service life. At the same time, the resistance strain gauge sensitive element of the large deformation displacement gauge adopts a fully sealed structure, which can further reduce the influence of the external environment on the test accuracy and meet the measurement requirements of micro-strain from -10000 to 10000.

[0030] The resistance strain gauge 20 is arranged in the same direction as the straight section 13, that is, the length of the resistance strain gauge 20 is arranged along the length direction of the straight section 13; preferably, the resistance strain gauge 20 and the straight section 13 are connected by adhesive.

[0031] To further explain, the first connecting segment 11 and the second connecting segment 15 are both arranged parallel to the straight segment 13. The length of the first connecting segment 11 and the length of the second connecting segment 15 are the same. Both the first connecting segment 11 and the second connecting segment 15 are provided with connecting holes 17. In use, the left and right ends of the elastic sensitive element 10 are fixed to the displacement transmission mechanism that can sense displacement changes through the connecting holes 17, ensuring that the connection is simple and reliable.

[0032] The elastic sensitive element 10 also includes two inclined segments 16. The two inclined segments 16 are located on the left and right sides of the straight segment 13. The first arc segment 12 and the second arc segment 14 are connected to the straight segment 13 through the corresponding inclined segments 16. The central angle of the first arc segment 12 and the central angle of the second arc segment 14 are the same.

[0033] The large deformation displacement gauge uses a resistance strain gauge sensing element with a symmetrical structure along its length. Specifically, the first connecting segment 11 is symmetrically arranged about the vertical axis of symmetry of the straight segment 13, the first arc segment 12 and the second arc segment 14 are symmetrically arranged about the vertical axis of symmetry of the straight segment 13, and the two inclined segments 16 are symmetrically arranged about the vertical axis of symmetry of the straight segment 13.

[0034] The angle β between the inclined segment 16 and the straight segment 13 is 120° to 140°. Preferably, the first connecting segment 11, the first arc segment 12, the second arc segment 14 and the second connecting segment 15 are all located above the straight segment 13.

[0035] Correspondingly, the preferred distance a1 between the plane containing the lower surface of the first connecting segment 11 and the lower surface of the straight segment 13, and the distance a2 between the upper surface of the first connecting segment 11 and the plane where the parallel straight segment 13 intersects with the vertex of the first arc segment 12, satisfy a1 = a2.

[0036] The distance d between the left end face of the first connecting segment 11 and the right end face of the second connecting segment 15 is 45mm to 80mm; the widths of the inclined segment 16, the first connecting segment 11, the first arc segment 12, the straight segment 13, the second arc segment 14, and the second connecting segment 15 are the same and are all 4mm to 10mm; the distance a between the top of the first arc segment 12 and the bottom of the straight segment 13 is 5mm to 15mm.

[0037] Example 2 Based on the resistance strain gauge sensitive element for large deformation displacement meter described in Embodiment 1, the resistance strain gauge 20 for large deformation displacement meter provided in this embodiment includes a first strain unit 30 and a second strain unit 40.

[0038] The first strain unit 30 includes a first measuring grid 31, a first pad 32, a second pad 33, and a first zero-adjustment grid 34; the second strain unit 40 includes a second measuring grid 41, a third pad 42, a fourth pad 43, and a second zero-adjustment grid 44.

[0039] In this configuration, both the first measuring grid 31 and the second measuring grid 41 are arranged in an S-shape. The first measuring grid 31 is nested outside the second measuring grid 41, and the spacing between the first measuring grid 31 and the second measuring grid 41 is equal. At this time, the first measuring grid 31 and the second measuring grid 41 are arranged in the same direction. Preferably, the first measuring grid 31 and the second measuring grid 41 are arranged coaxially, that is, the first measuring grid 31 and the second measuring grid 41 are symmetrical about the same axis of symmetry. At the same time, the resistance value of the first measuring grid 31 is the same as the resistance value of the second measuring grid 41. The first pad 32, the second pad 33, the third pad 42 and the fourth pad 43 are all used as terminals of the Wheatstone bridge circuit.

[0040] The first strain unit 30 and the second strain unit 40 are nested to mainly solve the problems of concentrated strain area, small patch space, and poor consistency of tensile and compressive strain changes in the current resistance strain gauge sensitive element for large deformation displacement gauges. At the same time, by adding the first zero adjustment grid 34 and the second zero adjustment grid 44, it has a zero-point adjustment function and a zero-point compensation function, which solves the problem of poor temperature performance of the resistance strain gauge sensitive element for large deformation displacement gauges.

[0041] One end of the first measuring gate 31 is connected to the first pad 32 via the first zeroing gate 34, and the other end of the first measuring gate 31 is connected to the second pad 33; one end of the second measuring gate 41 is connected to the third pad 42, and the other end of the second measuring gate 41 is connected to the fourth pad 43 via the second zeroing gate 44.

[0042] Both the first zero-adjustment grid 34 and the second zero-adjustment grid 44 are arranged in an S-shape. The directions of the first zero-adjustment grid 34, the second zero-adjustment grid 44, the first measuring grid 31, and the second measuring grid 41 are all the same. The initial zero point compensation can be achieved by adjusting the resistance value of the first zero-adjustment grid 34 or the resistance value of the second zero-adjustment grid 44.

[0043] The first pad 32 and the second pad 33 are located on the same side, and the third pad 42 and the fourth pad 43 are located on the same side.

[0044] refer to Figure 3 The resistance strain gauge 40 includes two zero-adjustment grids, namely the first zero-adjustment grid 31 and the second zero-adjustment grid 41. At this time, the first strain unit 30 is sleeved outside the second strain unit 40, the third pad 42 is close to the first pad 32, the first pad 32 is located outside the third pad 42, the first zero-adjustment grid 34 is close to the third pad 42, and a gap is reserved between the third pad 42 and the first zero-adjustment grid 34; similarly, the fourth pad 43 is close to the second pad 33, the second pad 33 is located outside the fourth pad 43, and a gap is reserved between the second zero-adjustment grid 44 and the second pad 33; so that the first pad 32, the second pad 33, the third pad 42, the fourth pad 43, the first zero-adjustment grid 34 and the second zero-adjustment grid 44 are all located on the same side of the first measuring grid 31 and the second measuring grid 41.

[0045] Further preferably, the first strain unit 30 further includes a third zero-adjustment grid 35, and the second strain unit 40 further includes a fourth zero-adjustment grid 45; the third zero-adjustment grid 35 is connected between the other end of the first measuring grid 31 and the second pad 33; the fourth zero-adjustment grid 45 is connected between one end of the second measuring grid 41 and the third pad 42; at this time, the directions of the first zero-adjustment grid 34, the second zero-adjustment grid 44, the third zero-adjustment grid 35 and the fourth zero-adjustment grid 45 are all the same; that is, the resistance strain gauge 40 includes four zero-adjustment grids.

[0046] refer to Figure 4 The first pad 32, the second pad 33, the third pad 42, the fourth pad 43, the first zero-adjustment gate 34, the second zero-adjustment gate 44, the third zero-adjustment gate 35, and the fourth zero-adjustment gate 45 are all located on the same side. The first pad 32, the second pad 33, the third pad 42, and the fourth pad 43 are arranged side by side, and the first zero-adjustment gate 34, the second zero-adjustment gate 44, the third zero-adjustment gate 35, and the fourth zero-adjustment gate 45 are arranged side by side.

[0047] refer to Figure 5 The first pad 32, the second pad 33, the first zero gate 34 and the third zero gate 35 are located on the same side, and the third pad 42, the fourth pad 43, the second zero gate 44 and the fourth zero gate 45 are located on the same side.

[0048] The advantages of this utility model are: Based on the resistance strain gauge sensitive element for large deformation displacement gauges described in Embodiments 1 and 2, this utility model has the advantages of large measurement range, high reliability, high consistency between tensile and compressive strain changes, small difference between tensile and compressive output, and small influence of external ambient temperature on test accuracy. It can be used to monitor changes in deformation, stress, cracks and fissures in structures.

[0049] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit this utility model. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of this utility model.

[0050] Although the present invention has been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these inventions without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A resistance strain gauge sensing element for a large deformation displacement meter, characterized in that, Includes an elastic sensing element (10) and a resistance strain gauge (20); The elastic sensitive element (10) includes a first connecting segment (11), a first arc segment (12), a straight segment (13), a second arc segment (14), and a second connecting segment (15) connected in sequence; the resistance strain gauges (20) are respectively arranged on the upper and lower sides of the straight segment (13), and the resistance strain gauges (20) are arranged in the same direction as the straight segment (13).

2. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 1, characterized in that, The central angle of the first arc segment (12) is the same as that of the second arc segment (14), and the first connecting segment (11) and the second connecting segment (15) are both parallel to the straight segment (13). The first connecting segment (11) and the second connecting segment (15) are symmetrical about the vertical axis of symmetry of the straight segment (13); the first arc segment (12) and the second arc segment (14) are symmetrical about the vertical axis of symmetry of the straight segment (13).

3. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 2, characterized in that, The length of the first connecting segment (11) is the same as the length of the second connecting segment (15), and the outer diameter of the first arc segment (12) is the same as the outer diameter of the second arc segment (14).

4. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 3, characterized in that, The left and right sides of the straight section (13) are connected to the first arc section (12) and the second arc section (14) respectively through the inclined section (16). The first connecting section (11), the first arc section (12), the second arc section (14) and the second connecting section (15) are all located above the straight section (13).

5. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 4, characterized in that, The angle between the inclined section (16) and the straight section (13) is 120° to 140°. The distance between the left end face of the first connecting section (11) and the right end face of the second connecting section (15) is 45mm to 80mm. The widths of the inclined section (16), the first connecting section (11), the first arc section (12), the straight section (13), the second arc section (14), and the second connecting section (15) are the same and are all 4mm to 10mm. The distance between the top of the first arc section (12) and the bottom of the straight section (13) is 5mm to 15mm.

6. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 5, characterized in that, The inclined section (16), the first connecting section (11), the first arc section (12), the straight section (13), the second arc section (14) and the second connecting section (15) are an integral structure; the resistance strain gauge (20) is pasted on the upper and lower sides of the straight section (13).

7. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 1, characterized in that, The resistance strain gauge (20) includes a first strain unit (30) and a second strain unit (40); The first strain unit (30) includes a first measuring grid (31), a first pad (32), a second pad (33), and a first zeroing grid (34); the second strain unit (40) includes a second measuring grid (41), a third pad (42), a fourth pad (43), and a second zeroing grid (44). The first measuring gate (31) is nested outside the second measuring gate (41) and is arranged in the same direction as the second measuring gate (41). One end of the first measuring gate (31) is connected to the first pad (32) through the first zeroing gate (34), and the other end of the first measuring gate (31) is connected to the second pad (33). One end of the second measuring gate (41) is connected to the third pad (42), and the other end of the second measuring gate (41) is connected to the fourth pad (43) through the second zeroing gate (44). The resistance value of the first measuring grid (31) is the same as the resistance value of the second measuring grid (41). The directions of the first zeroing grid (34), the second zeroing grid (44), the first measuring grid (31), and the second measuring grid (41) are all the same. The first measuring grid (31) and the second measuring grid (41) are coaxially arranged.

8. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 7, characterized in that, The first strain unit (30) further includes a third zero-adjustment grid (35), and the second strain unit (40) further includes a fourth zero-adjustment grid (45). The third zeroing gate (35) is connected between the other end of the first measuring gate (31) and the second pad (33); the fourth zeroing gate (45) is connected between one end of the second measuring gate (41) and the third pad (42).

9. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 8, characterized in that, The directions of the first zero-adjustment gate (34), the second zero-adjustment gate (44), the third zero-adjustment gate (35), and the fourth zero-adjustment gate (45) are all the same.

10. The resistance strain gauge sensing element for a large deformation displacement gauge according to claim 8, characterized in that, The first pad (32) and the second pad (33) are located on the same side, and the third pad (42) and the fourth pad (43) are located on the same side.

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