High response frequency strain gauge compatible with multiple strain directions

Abstract

The application relates to the technical field of resistance strain gauges, and particularly relates to a high-response-frequency resistance strain gauge compatible with multiple strain directions, which comprises a base layer, a strain wire and an indicating unit; the middle part of the base layer is provided with a perforation; the indicating unit is arranged in the perforation; a plurality of upper pulleys are rotationally arranged on one side of the base layer along the width direction; the distance between adjacent upper pulleys and lower pulleys in the length direction is the same; the strain wire is sequentially arranged around the upper pulleys and the lower pulleys; the base layer is rotationally provided with an upper tension pulley and a lower tension pulley; one end of the strain wire is connected with the upper tension pulley; the other end of the strain wire is connected with the lower tension pulley. According to the length of the strain wire between the upper pulley and the adjacent lower pulley, if the length is greater than the initial length L, it is judged that the strain of the measured object occurs in the width direction; if the length is less than the initial length L, it is judged that the strain of the measured object occurs in the length direction. Two groups of strain wires are not needed, and the cost is effectively saved.

Description

Technical Field

[0001] This invention relates to the field of resistance strain gauge technology, and more specifically to a high-response-frequency resistance strain gauge compatible with multiple strain directions. Background Technology

[0002] In the field of stress and strain testing of mechanical structures, resistance strain gauges are widely used for monitoring the strain state of objects such as bridges, building components, and mechanical parts due to their advantages of simple structure, low cost, and stable detection accuracy. They are core sensing elements for assessing structural stress safety and optimizing design parameters. Their working principle is based on the strain effect of metallic or semiconductor materials. When the strain gauge deforms with the object being measured, the resistance value of its internal sensitive grid changes accordingly. By measuring the change in resistance value, the magnitude of the strain on the object can be inferred.

[0003] In practical applications, strain often exists simultaneously in multiple orthogonal directions along the X and Y axes. To achieve accurate detection of strain in these orthogonal directions, existing technical solutions generally adopt the method of attaching multiple sets of strain gauges. That is, at least two independent sets of resistance strain gauges need to be attached along different orthogonal directions at the same detection point or adjacent detection area of ​​the object to be measured. Each set of strain gauges can only detect the strain in the direction of its sensitive grid axis.

[0004] This method of relying on multiple strain gauges to detect strain in orthogonal directions has obvious technical limitations: on the one hand, the attachment of multiple strain gauges not only increases the complexity of the construction process, but also places higher demands on the accuracy of the attachment position; on the other hand, the use of multiple strain gauges increases the overall cost of the sensing system, and is also limited in some space-constrained application scenarios. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned shortcomings in the prior art by providing a high-response frequency resistance strain gauge compatible with multiple strain directions.

[0006] The objective of this invention is achieved through the following technical solution: a high-response frequency resistance strain gauge compatible with multiple strain directions, comprising a substrate layer, a strain wire, and an indicating unit; a perforation is provided in the middle of the substrate layer; the indicating unit is disposed in the perforation;

[0007] The base layer is provided with multiple upper pulleys on one side along the width direction; the multiple upper pulleys are equally spaced along the length direction; the base layer is provided with multiple lower pulleys on the other side along the width direction; the multiple lower pulleys are equally spaced along the length direction; the upper pulleys and lower pulleys are staggered in the length direction; the distance between adjacent upper pulleys and lower pulleys in the length direction is the same;

[0008] The strain wire is wound sequentially around the upper pulley and the lower pulley; the base layer is rotatably provided with an upper tensioning wheel and a lower tensioning wheel; one end of the strain wire is connected to the upper tensioning wheel; the other end of the strain wire is connected to the lower tensioning wheel.

[0009] The present invention is further configured such that the upper tensioning wheel and the plurality of upper pulleys are located on the same horizontal line; the distance between the upper tensioning wheel and the upper pulleys is equal to the distance between two adjacent upper pulleys.

[0010] The present invention is further configured such that the lower tensioning wheel and the plurality of lower sliding wheels are located on the same horizontal line; the distance between the lower tensioning wheel and the lower sliding wheels is equal to the distance between two adjacent lower sliding wheels.

[0011] The present invention is further configured such that the angle between the two strain wires between the upper pulley and the two adjacent lower pulleys is less than 90 degrees; and the angle between the two strain wires between the lower pulley and the two adjacent upper pulleys is less than 90 degrees.

[0012] The present invention is further configured such that the indicating unit includes a circular body; a rotating column is provided at the center of the bottom of the circular body; a first fixed column and a second fixed column are movably provided at the bottom of the circular body; a first flexible connecting line is provided between the first fixed column and the rotating column; a second flexible connecting line is provided between the second fixed column and the rotating column; the diameters of the first flexible connecting line, the second flexible connecting line and the rotating column are located on the same horizontal line.

[0013] The invention is further configured such that a pointer is rotatably provided on the top of the circular body; the middle part of the pointer is fixedly connected to the rotating column.

[0014] The present invention is further configured such that: the bottom of the first fixing column is provided with a first adhesive layer; the bottom of the second fixing column is provided with a second adhesive layer; the bottom of the circular body is provided with a third adhesive layer; the bottom of the base layer is provided with a fourth adhesive layer; and the first adhesive layer, the second adhesive layer, the third adhesive layer and the fourth adhesive layer are located at the same height.

[0015] The present invention is further configured such that a flexible pressure ring is provided between the top of the circular body and the perforation of the base layer.

[0016] The present invention is further configured such that the base layer has a first mark at one end of the perforation that mates with one end of the pointer; and the base layer has a second mark at the other end of the perforation that mates with the other end of the pointer.

[0017] The present invention is further configured such that the straight lines containing the multiple upper pulleys, the straight lines containing the multiple lower pulleys, and the straight lines containing the first mark and the second mark are arranged parallel to each other.

[0018] The beneficial effects of the present invention are as follows: The present invention can determine the strain in the width direction of the test object by detecting the strain wire length between the upper pulley and the adjacent lower pulley. If the length is greater than the initial length L, the strain in the length direction of the test object is determined. This eliminates the need to set two sets of strain wires, effectively saving costs. Attached Figure Description

[0019] The invention will be further illustrated with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the invention. For those skilled in the art, other drawings can be obtained based on the following drawings without any creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of the present invention;

[0021] Figure 2 This is a structural schematic diagram from another perspective of the present invention;

[0022] Figure 3 This is a front view of the present invention;

[0023] Figure 4 This is an exploded view of the structure of the present invention;

[0024] Figure 5 This is a schematic diagram of the structure of the indicator unit of the present invention;

[0025] Figure 6 This is a schematic diagram of the structure of the indicating unit of the present invention from another perspective;

[0026] The components are: 1. Base layer; 11. Perforation; 12. Flexible pressure ring; 13. First mark; 14. Second mark; 15. Fourth adhesive layer; 2. Strain wire; 31. Upper pulley; 32. Lower pulley; 41. Upper tensioning pulley; 42. Lower tensioning pulley; 5. Circular body; 51. Third adhesive layer; 6. Rotating column; 61. Pointer; 71. First fixing column; 72. First flexible connecting line; 73. First adhesive layer; 81. Second fixing column; 82. Second flexible connecting line; 83. Second adhesive layer. Detailed Implementation

[0027] The present invention will be further described in conjunction with the following embodiments.

[0028] Depend on Figures 1 to 6 As can be seen, the high-response frequency resistance strain gauge compatible with multiple strain directions described in this embodiment includes a base layer 1, a strain wire 2, and an indicating unit; a perforation 11 is provided in the middle of the base layer 1; the indicating unit is disposed in the perforation 11;

[0029] The base layer 1 is provided with a plurality of upper pulleys 31 rotatably along one side of the width direction; the plurality of upper pulleys 31 are arranged at equal intervals along the length direction; the base layer 1 is provided with a plurality of lower pulleys 32 rotatably along the other side of the width direction; the plurality of lower pulleys 32 are arranged at equal intervals along the length direction; the upper pulleys 31 and lower pulleys 32 are staggered in the length direction; the distance between adjacent upper pulleys 31 and lower pulleys 32 in the length direction is the same;

[0030] The strain wire 2 is wound sequentially around the upper pulley 31 and the lower pulley 32; the base layer 1 is rotatably provided with an upper tensioning wheel 41 and a lower tensioning wheel 42; one end of the strain wire 2 is connected to the upper tensioning wheel 41; the other end of the strain wire 2 is connected to the lower tensioning wheel 42.

[0031] Specifically, in this embodiment, the high-response frequency resistance strain gauge compatible with multiple strain directions, when measuring the object to be measured, places the indicating unit in the perforation 11, then fixes the indicating unit and the base layer 1 to the surface of the object to be measured, and then rotates the upper tensioning wheel 41 and the lower tensioning wheel 42 to make the strain wire 2 taut. Then, the initial length L of the strain wire 2 between the upper pulley 31 and the adjacent lower pulley 32, the distance Y between the upper pulley 31 and the lower pulley 32 in the width direction, and the distance X between the upper pulley 31 and the lower pulley 32 in the length direction are measured. A right triangle is formed between X, Y, and L. ;

[0032] When the object under test is stretched along its width, at the time of strain occurrence, the length l1 of the strain wire 2 between the upper pulley 31 and the adjacent lower pulley 32 corresponding to that section is: Where y is the tensile deformation in the width direction, v is the Poisson's ratio of the material to be measured, and vy is the tensile deformation in the length direction. Since the Poisson's ratio v is less than 1 and Y is much greater than X, l1 is greater than L.

[0033] When the object under test is stretched along its length, at the time of strain occurrence, the length l2 of the strain wire 2 between the upper pulley 31 and the adjacent lower pulley 32 corresponding to that section is: Where x is the tensile deformation in the length direction, v is the Poisson's ratio of the material to be measured, and vx is the tensile deformation in the width direction. Since the Poisson's ratio v is less than 1 and Y is much greater than X, l2 is less than L.

[0034] This embodiment, through the above settings, can determine that the object under test has strain in the width direction if the strain wire 2 between the upper pulley 31 and the adjacent lower pulley 32 is greater than the initial length L, and that the object under test has strain in the length direction if the length is less than the initial length L. In addition, the relationship between the magnitude of the strain and the output resistance value can be obtained through calibration. This embodiment, through the above settings, eliminates the need to set two sets of strain wires 2, effectively saving costs.

[0035] This embodiment describes a high-response frequency resistance strain gauge compatible with multiple strain directions. The upper tensioning wheel 41 and multiple upper pulleys 31 are located on the same horizontal line; the distance between the upper tensioning wheel 41 and the upper pulleys 31 is equal to the distance between two adjacent upper pulleys 31. This configuration ensures measurement accuracy.

[0036] This embodiment describes a high-response frequency resistance strain gauge compatible with multiple strain directions. The lower tensioning wheel 42 and multiple lower sliding wheels 32 are located on the same horizontal line; the distance between the lower tensioning wheel 42 and the lower sliding wheels 32 is equal to the distance between two adjacent lower sliding wheels 32. This configuration ensures measurement accuracy.

[0037] This embodiment describes a high-response frequency resistance strain gauge compatible with multiple strain directions. The angle between the two strain wires 2 between the upper pulley 31 and two adjacent lower pulleys 32 is less than 90 degrees; similarly, the angle between the two strain wires 2 between the lower pulley 32 and two adjacent upper pulleys 31 is also less than 90 degrees. This arrangement ensures that the distance Y between the upper pulley 31 and the lower pulley 32 in the width direction is much greater than the distance X between them in the length direction.

[0038] This embodiment describes a high-response frequency resistance strain gauge compatible with multiple strain directions. The indicating unit includes a circular body 5; a rotating column 6 is located at the center of the bottom of the circular body 5; a first fixed column 71 and a second fixed column 81 are movably arranged at the bottom of the circular body 5; a first flexible connecting line 72 is provided between the first fixed column 71 and the rotating column 6; a second flexible connecting line 82 is provided between the second fixed column 81 and the rotating column 6; the diameters of the first flexible connecting line 72, the second flexible connecting line 82, and the rotating column 6 are located on the same horizontal line. In this embodiment, a pointer 61 is rotatably mounted on the top of the circular body 5; the middle part of the pointer 61 is fixedly connected to the rotating column 6. This embodiment describes a high-response frequency resistance strain gauge compatible with multiple strain directions. The bottom of the first fixing post 71 is provided with a first adhesive layer 73; the bottom of the second fixing post 81 is provided with a second adhesive layer 83; the bottom of the circular body 5 is provided with a third adhesive layer 51; and the bottom of the base layer 1 is provided with a fourth adhesive layer 15. The first adhesive layer 73, the second adhesive layer 83, the third adhesive layer 51, and the fourth adhesive layer 15 are located at the same height. In this embodiment, the base layer 1 has a first mark 13 at one end of the perforation 11 that mates with one end of the pointer 61; and a second mark 14 at the other end of the perforation 11 that mates with the other end of the pointer 61. In this embodiment, the straight lines containing the multiple upper pulleys 31, the multiple lower pulleys 32, and the first mark 13 and the second mark 14 are arranged parallel to each other.

[0039] Specifically, in this embodiment, the high-response frequency resistance strain gauge compatible with multiple strain directions is first used by bonding the first adhesive layer 73, the second adhesive layer 83, and the third adhesive layer 51 to the surface of the object to be tested. Then, the object to be tested is stretched to apply stress. After the object to be tested is stretched, the first fixed column 71 and the second fixed column 81 will change their positions at the bottom of the circular body 5. Through the action of the first flexible connecting line 72 and the second flexible connecting line 82, the rotating column 6 is driven to rotate, so that the pointer 61 is parallel to the direction of the strain force. Then, the stretching of the object to be tested is removed, and the pointer 61 maintains its current position under the action of friction.

[0040] Next, the base layer 1 is placed outside the indicator unit, so that the first mark 13 and the second mark 14 are aligned with the two ends of the pointer 61 respectively, and the fourth adhesive layer 15 is bonded to the surface of the object to be tested, thereby completing the positioning of the base layer 1.

[0041] Next, by rotating the upper tensioning wheel 41 and the lower tensioning wheel 42, the strain wire 2 is brought to a taut state. Then, the initial length L of the strain wire 2 between the upper pulley 31 and the adjacent lower pulley 32, the distance Y between the upper pulley 31 and the lower pulley 32 in the width direction, and the distance X between the upper pulley 31 and the lower pulley 32 in the length direction are measured. A right triangle is formed between X, Y, and L. ;

[0042] When the object under test is stretched along its width, at the time of strain occurrence, the length l1 of the strain wire 2 between the upper pulley 31 and the adjacent lower pulley 32 corresponding to that section is: Where y is the tensile deformation in the width direction, v is the Poisson's ratio of the material to be measured, and vy is the tensile deformation in the length direction. Since the Poisson's ratio v is less than 1 and Y is much greater than X, l1 is greater than L.

[0043] When the object under test is stretched along its length, at the time of strain occurrence, the length l2 of the strain wire 2 between the upper pulley 31 and the adjacent lower pulley 32 corresponding to that section is: Where x is the tensile deformation in the length direction, v is the Poisson's ratio of the material to be measured, and vx is the tensile deformation in the width direction. Since the Poisson's ratio v is less than 1 and Y is much greater than X, l2 is less than L.

[0044] This embodiment, through the above settings, can determine that the object under test has strain in the width direction if the strain wire 2 between the upper pulley 31 and the adjacent lower pulley 32 is greater than the initial length L, and that the object under test has strain in the length direction if the length is less than the initial length L. In addition, the relationship between the magnitude of the strain and the output resistance value can be obtained through calibration. This embodiment, through the above settings, eliminates the need to set two sets of strain wires 2, effectively saving costs.

[0045] The high-response frequency resistance strain gauge compatible with multiple strain directions described in this embodiment has a flexible pressure ring 12 between the top of the circular body 5 and the perforation 11 of the base layer 1. This arrangement ensures that the indicating unit is subjected to uniform force.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A high-response frequency resistance strain gauge compatible with multiple strain directions, characterized in that: It includes a base layer (1), a strain wire (2), and an indicator unit; the base layer (1) has a perforation (11) in the middle; the indicator unit is located in the perforation (11); The base layer (1) is provided with multiple upper pulleys (31) on one side along the width direction; the multiple upper pulleys (31) are arranged at equal intervals along the length direction; the base layer (1) is provided with multiple lower pulleys (32) on the other side along the width direction; the multiple lower pulleys (32) are arranged at equal intervals along the length direction; the upper pulleys (31) and lower pulleys (32) are staggered in the length direction; the distance between adjacent upper pulleys (31) and lower pulleys (32) in the length direction is the same; The strain wire (2) is wound sequentially around the upper pulley (31) and the lower pulley (32); the base layer (1) is rotatably provided with an upper tensioning wheel (41) and a lower tensioning wheel (42); one end of the strain wire (2) is connected to the upper tensioning wheel (41); the other end of the strain wire (2) is connected to the lower tensioning wheel (42); Based on the length of the strain wire (2) between the upper pulley (31) and the adjacent lower pulley (32), if the length is greater than the initial length L, it is determined that the test object has strain in the width direction; if the length is less than the initial length L, it is determined that the test object has strain in the length direction.

2. The high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 1, characterized in that: The upper tensioning wheel (41) and multiple upper pulleys (31) are located on the same horizontal line; the distance between the upper tensioning wheel (41) and the upper pulleys (31) is equal to the distance between two adjacent upper pulleys (31).

3. The high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 1, characterized in that: The lower tensioning wheel (42) and the multiple lower sliding wheels (32) are located on the same horizontal line; the distance between the lower tensioning wheel (42) and the lower sliding wheels (32) is equal to the distance between two adjacent lower sliding wheels (32).

4. The high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 1, characterized in that: The two strain wires (2) between the upper pulley (31) and the two adjacent lower pulleys (32) have an included angle of less than 90 degrees; the two strain wires (2) between the lower pulley (32) and the two adjacent upper pulleys (31) have an included angle of less than 90 degrees.

5. A high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 1, characterized in that: The indicating unit includes a circular body (5); a rotating column (6) is provided at the center of the bottom of the circular body (5); a first fixed column (71) and a second fixed column (81) are movably provided at the bottom of the circular body (5); a first flexible connecting line (72) is provided between the first fixed column (71) and the rotating column (6); a second flexible connecting line (82) is provided between the second fixed column (81) and the rotating column (6); the diameters of the first flexible connecting line (72), the second flexible connecting line (82) and the rotating column (6) are located on the same horizontal line.

6. A high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 5, characterized in that: The top of the circular body (5) is rotatably equipped with a pointer (61); the middle part of the pointer (61) is fixedly connected to the rotating column (6).

7. A high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 5, characterized in that: The bottom of the first fixing post (71) is provided with a first adhesive layer (73); the bottom of the second fixing post (81) is provided with a second adhesive layer (83); the bottom of the circular body (5) is provided with a third adhesive layer (51); the bottom of the base layer (1) is provided with a fourth adhesive layer (15); the first adhesive layer (73), the second adhesive layer (83), the third adhesive layer (51) and the fourth adhesive layer (15) are located at the same height.

8. A high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 5, characterized in that: A flexible pressure ring (12) is provided between the top of the circular body (5) and the perforation (11) of the base layer (1).

9. A high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 6, characterized in that: The base layer (1) has a first mark (13) at one end of the perforation (11) that mates with one end of the pointer (61); the base layer (1) has a second mark (14) at the other end of the perforation (11) that mates with the other end of the pointer (61).

10. A high-response frequency resistance strain gauge compatible with multiple strain directions according to claim 9, characterized in that: The straight lines containing the multiple upper pulleys (31), the straight lines containing the multiple lower pulleys (32), and the straight lines containing the first mark (13) and the second mark (14) are set parallel to each other.

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