High-sensitivity strain gauge

Abstract

The utility model belongs to the technical field of engineering monitoring equipment, and particularly relates to a high-sensitivity strain gauge, which comprises a shell, a fixed column, a vibrating wire and a coil, a central through hole is formed in the fixing column in the axial direction; the central through hole is used for accommodating a vibrating wire; two ends of the vibrating wire are respectively fixed at two ends of the fixed column; the fixed column comprises a fixed section and a sensing section, and the sensing section is connected with the fixed section through a connecting section; the induction section is provided with an induction hole, the induction hole is communicated with the central through hole, and the coil is installed in the induction hole; the fixed column is also provided with a notch, and the notch is used for increasing the sensitivity of the strain gauge. The strain gauge is simple in structure, and the plurality of notches are arranged on the fixed column, so that materials are saved, deformation of the fixed column is facilitated, and the sensitivity of the whole strain gauge is improved; a plurality of sealing ring grooves are further formed in the fixing column and the shell, and corresponding sealing rings are installed in a matched mode, so that the device has good sealing performance.

Description

Technical Field

[0001] The utility model relates to the technical field of engineering monitoring equipment, in particular to a high-sensitivity strain gauge. Background Art

[0002] Strain gauges are primarily used to monitor strain in geotechnical engineering and other concrete structures. They are suitable for long-term burial inside buildings to measure internal strain, or they can be installed on the surface of objects to monitor strain, such as steel pipes, rebar, bridges, and building surfaces. Strain gauges are a common sensor used in engineering construction. However, some existing vibrating-wire strain gauges have low sensitivity, making them unsuitable for small-range, high-precision measurements. Utility Model Content

[0003] The purpose of the utility model is to solve the deficiencies of the prior art and provide a high-sensitivity strain gauge.

[0004] The technical solution of the utility model is: a high-sensitivity strain gauge, including a shell, a fixed column, a vibrating wire and a coil; the fixed column is provided with a central through hole along the axial direction; the central through hole is used to accommodate the vibrating wire, and the two ends of the vibrating wire are respectively fixed to the two ends of the fixed column; the fixed column includes a fixed section and a sensing section, and the sensing section and the fixed section are connected by a connecting section; the fixed section and the sensing section are both provided with threads for matching with the shell; the sensing section is provided with a sensing hole, the sensing hole is connected to the central through hole, and the coil is installed in the sensing hole and can be used to sense the vibration frequency of the vibrating wire; a notch is also provided on the fixed column, and the notch is used to increase the sensitivity of the strain gauge.

[0005] Furthermore, the direction of the notch is perpendicular to the axial direction of the fixing column.

[0006] Furthermore, the notch is provided on the sensing section; and the depth of the notch is greater than the radius of the sensing section but smaller than the diameter of the sensing section.

[0007] Furthermore, the notch is provided between the sensing hole and the thread on the sensing segment.

[0008] Furthermore, there are at least two notches.

[0009] Furthermore, the opening directions of adjacent notches are staggered.

[0010] Furthermore, the vibrating wire is mounted on the fixing column via a fastening assembly, which includes a base and a screw.

[0011] Furthermore, the base includes a base plate and two clamping plates mounted on the base plate. A mounting hole is provided in the middle of the base plate, communicating with the gap between the two clamping plates. The mounting hole facilitates passage of the vibrating wire. The clamping plates are sized to match the stepped hole.

[0012] Furthermore, stepped holes are provided at both ends of the fixing column, and the stepped holes are used to cooperate with the base. Threaded holes are provided on the side walls near the two ends of the fixing column, and the threaded holes are connected to the stepped holes; the screws cooperate with the threaded holes to squeeze the splint installed in the stepped holes.

[0013] Furthermore, a plurality of sealing ring grooves are provided on the fixing column and the shell; the sealing ring grooves are used for installing sealing rings.

[0014] Furthermore, the housing includes left and right end covers on both sides and a sleeve in the middle. The two end covers and the sleeve, as well as the end covers and the fixing column are connected via threaded structures.

[0015] Compared with the prior art, the present invention has the following beneficial effects: the strain gauge in the present invention has a simple structure, and a plurality of notches are provided on the fixing column. The notches not only save materials, but also facilitate deformation of the fixing column under the action of external stress, thereby improving the sensitivity of the entire strain gauge; in addition, a plurality of sealing ring grooves are provided on the fixing column and the housing, and corresponding sealing rings are installed together to ensure good sealing performance of the entire strain gauge. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the three-dimensional structure of Example 1 of the present utility model;

[0017] Figure 2 This is an exploded schematic diagram of Example 1 of the present utility model;

[0018] Figure 3 This is a schematic diagram of the internal structure of Example 1 of the present utility model after omitting some structures;

[0019] Figure 4 It is a cross-sectional schematic diagram of the vibrating wire assembled to the end of the fixed column in Example 1 of the present utility model;

[0020] Figure 5 This is a schematic diagram of the base in Example 1 of the present utility model;

[0021] In the figure: 1. Shell; 11. Left end cover; 12. Right end cover; 13. Sleeve; 2. Fixing column; 21. Fixing section; 22. Sensing section; 221. Sensing hole; 222. Notch; 23. Connecting section; 3. Coil; 4. Vibrating wire; 5. Base; 51. Substrate; 52. Clamp; 53. Mounting hole; 6. Thread; 7. Sealing ring groove; 8. Screw. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below with reference to specific embodiments. Methods or functional components not specifically described in the embodiments are all prior art. Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by technicians in the technical field of the present invention.

[0023] Example 1

[0024] like Figure 1-5 As shown, this embodiment is a high-sensitivity strain gauge, including a housing 1, a fixed column 2, a vibrating wire 4 and a coil 3; the fixed column 2 is provided with a central through hole along the axial direction; the central through hole is used to accommodate the vibrating wire 4, and the two ends of the vibrating wire 4 are respectively fixed to the two ends of the fixed column 2; the fixed column 2 includes a fixed section 21 and a sensing section 22, and the sensing section 22 is connected to the fixed section 21 by a connecting section 23; the fixed section 21 and the sensing section 22 are both provided with threads 6 for mating with the housing 1; the sensing section 22 is provided with a sensing hole 221, which is connected to the central through hole, and the coil 3 is installed in the sensing hole 221 to sense the vibration frequency of the vibrating wire 4; the fixed column 2 is also provided with a notch 222, which is used to increase the sensitivity of the strain gauge; the direction of the notch 222 is perpendicular to the axial direction of the fixed column 2.

[0025] In this embodiment, a notch 222 is provided on the sensing section 22; the depth of the notch 222 is greater than the radius of the sensing section 22, but less than the diameter of the sensing section 22. The notch 222 is provided between the sensing hole 221 and the thread 6 on the sensing section 22. Two notches 222 are provided, and the openings of the two notches 222 face opposite directions.

[0026] In this embodiment, the vibrating wire 4 is mounted on the fixed column 2 via a fastening assembly comprising a base 5 and screws 8. The base 5 comprises a base plate 51 and two clamping plates 52 mounted on the base plate 51. A mounting hole 53 is provided in the center of the base plate 51, communicating with the gap between the two clamping plates 52. Mounting hole 53 facilitates the passage of the vibrating wire 4.

[0027] In this embodiment, stepped holes are provided at both ends of the fixing column 2, and the stepped holes are used to cooperate with the base 5 so that the splint 52 can be fully inserted into the stepped holes, but the base plate 51 is blocked by a step surface in the stepped hole; a threaded hole is provided on the side wall near the end of the fixing column 2, and the threaded hole is communicated with the stepped hole; the screw 8 cooperates with the threaded hole to squeeze the splint 52 located in the stepped hole, so that the two splints are pressed against each other, and the vibrating wire 4 between the splints can be clamped.

[0028] In this embodiment, multiple sealing ring grooves 7 are provided on both the fixed section 21 and the sensing section 22. These grooves are used to mount sealing rings, ensuring a good seal. In this embodiment, the housing 1 comprises left and right end caps 12 on either side and a central sleeve 13. Both the left and right end caps 11 and 12 are provided with both internal and external threads, and the sleeve 13 is also provided with internal threads. This allows the threads 6 to connect the two end caps to the sleeve 13, as well as to connect the end caps to the fixed column 2.

[0029] When installing the strain gauge in this embodiment, first, a base 5 is mounted on the fixed column 2, with the clamping plate 52 of the base 5 inserted into the stepped hole, ensuring that one clamping plate 52 faces the front of the threaded hole. Then, the vibrating wire 4 is passed through the mounting hole 53 on the base plate 51, passes through the gap between the two clamping plates 52 and the central through hole, and then passes through the other side of the fixed column 2. The screw 8 at this end is then tightened so that the two clamping plates 52 clamp the vibrating wire 4. Similarly, the base 5 is mounted on the other end of the fixed column 2. After the vibrating wire 4 is stretched to a predetermined initial tension, the corresponding screw 8 at the other end is tightened. In this way, both ends of the vibrating wire 4 are clamped, and the vibrating wire 4 is completely mounted on the fixed column 2. The actual use method of the strain gauge in this embodiment is the same as that of existing strain gauges of the same type, but the strain gauge in this embodiment is provided with multiple notches 222 on the fixed column 2, making the fixed column 2 more susceptible to deformation, thereby increasing sensitivity and enabling the measurement of smaller strains.

[0030] The above are only some embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have combinations and variations of the aforementioned technical features. Without departing from the spirit and scope of the present invention, those skilled in the art can improve, modify, or replace the present invention with equivalents, or apply the structure or method of the present invention to other fields to achieve the same effect, which all fall within the scope of protection included in the present invention.

Claims

1. A high-sensitivity strain gauge, comprising a housing, characterized in that: It also includes a fixed column, a vibrating wire and a coil; a central through hole is axially arranged on the fixed column; the central through hole is used to accommodate the vibrating wire, and the two ends of the vibrating wire are respectively fixed to the two ends of the fixed column; the fixed column includes a fixed section and a sensing section, and the sensing section and the fixed section are connected by a connecting section; the fixed section and the sensing section are both provided with threads for cooperating with the shell; the sensing section is provided with a sensing hole, the sensing hole is connected to the central through hole, and the coil is installed in the sensing hole; a notch is also provided on the fixed column, and the notch is used to increase the sensitivity of the strain gauge.

2. The high-sensitivity strain gauge according to claim 1, characterized in that: The direction of the notch is perpendicular to the axial direction of the fixing column.

3. The high-sensitivity strain gauge according to claim 2, characterized in that: The notch is provided on the sensing section; and the depth of the notch is greater than the radius of the sensing section but smaller than the diameter of the sensing section.

4. The high-sensitivity strain gauge according to claim 3, characterized in that: The notch is arranged between the sensing hole and the thread.

5. The high-sensitivity strain gauge according to claim 2, characterized in that: There are at least two notches.

6. The high-sensitivity strain gauge according to claim 5, characterized in that: The opening directions of adjacent notches are staggered with each other.

7. The high-sensitivity strain gauge according to claim 1, characterized in that: The vibrating wire is mounted on the fixing column via a fastening assembly, which includes a base and a screw.

8. The high-sensitivity strain gauge according to claim 7, characterized in that: The base comprises a base plate and two clamping plates arranged on the base plate. A mounting hole is arranged in the middle of the base plate, and the mounting hole is communicated with the gap between the two clamping plates.

9. The high-sensitivity strain gauge according to claim 8, characterized in that: Step holes are provided at both ends of the fixing column, and the step holes are used to cooperate with the base. Threaded holes are provided on the side walls near the two ends of the fixing column, and the threaded holes are connected to the step holes; the screws cooperate with the threaded holes to squeeze the splint installed in the step holes.

10. The high-sensitivity strain gauge according to claim 1, characterized in that: The fixing section and the induction section are both provided with a plurality of sealing ring grooves; the sealing ring grooves are used for installing sealing rings.

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