Strain gauge with parallel structure and capable of realizing laser resistance trimming
By adopting parallel structure and laser resistance adjustment technology in the strain gauge, the problems of poor temperature drift performance, large stress and serious wire grid damage in the traditional strain gauge resistance adjustment method are solved, and more stable resistance adjustment and higher sensor performance are achieved.
Patent Information
- Application Number
- CN202421943532.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-12
- Publication Date
- 2025-06-03
- Estimated Expiration
- 2034-08-12
AI Technical Summary
Traditional strain gauge resistance adjustment methods, such as physical polishing and chemical electrodemodulation, have problems such as poor temperature drift performance, high stress, serious wire grid damage and unstable resistance.
The strain gauge with a parallel structure adopts a strain gauge, and the wire gauge is flexibly adjusted by setting wire gauge of different lengths and connecting them in parallel.
It realizes flexible adjustment of resistance values, simplifies operation, improves the temperature drift performance and life of the sensor, while reducing the risk of zero point changes and accuracy reduction.
Smart Images
Figure CN222938635U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of sensors, and particularly to a strain gauge with a parallel structure capable of realizing laser trimming. Background Art
[0002] As a main electronic component in a sensor, a strain gauge plays a role in sensing pressure. During the production process of the strain gauge, according to the design requirements, the resistance value needs to be set, and the wire grid therein often determines the resistance value of the strain gauge. In traditional processing methods, basically, physical grinding trimming and chemical electrolytic trimming are used, and both of these methods have some drawbacks: 1. a. Different grinding amplitudes for each strain gauge trimmed by physical grinding will result in different thicknesses of the wire grid, so the heat generation of each strain gauge will be inconsistent, thus making the temperature drift performance of the produced sensors poor; b. To solve the problem that physical grinding trimming causes large stress on the strain gauge, large stress on the strain gauge itself will cause large zero-point changes in the produced sensors; c. Physical grinding trimming causes relatively high damage to the wire grid, resulting in a short service life of the produced sensors. 2. For chemical electrolytic trimming, it is very difficult to thoroughly clean the electrolyte after chemical electrolytic trimming. If thorough cleaning cannot be achieved, the produced sensors will undergo secondary power-on electrolysis during use, causing a slight change in the resistance value, resulting in a larger zero point and lower accuracy of the produced sensors. Content of the Utility Model
[0003] In order to solve the above technical problems, the utility model provides a strain gauge with a parallel structure capable of realizing laser trimming.
[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:
[0005] A strain gauge with a parallel structure capable of realizing laser trimming includes a substrate, on which a first pad and a second pad are provided, as well as a first wire grid, a second wire grid, a third wire grid, a fourth wire grid, and a fifth wire grid with different lengths. The first pad is connected to the first wire grid, the first wire grid is connected in parallel with the second wire grid, the second wire grid is connected in series with the third wire grid, the third wire grid is connected in series with the fourth wire grid, the fourth wire grid is connected in parallel with the fifth wire grid, and the fifth wire grid is connected to the second pad.
[0006] The lengths of the first wire grid, the second wire grid, the fourth wire grid, and the fifth wire grid are all less than the length of the third wire grid.
[0007] Centered on the third wire grid, the first wire grid and the second wire grid are symmetrically distributed with the fourth wire grid and the fifth wire grid.
[0008] A first connecting member is disposed between the first pad, the first grid and the second grid, and the first connecting member is respectively connected to the first pad, the first grid and the second grid; a second connecting member is disposed between the second pad, the fourth grid and the fifth grid, and the second connecting member is respectively connected to the second pad, the fourth grid and the fifth grid.
[0009] The substrate is coated, rotated and sprayed with polyimide resin or modified phenolic resin or polyether ether ketone or epoxy resin or glass fiber reinforced resin.
[0010] The first grid, the second grid, the third grid, the fourth grid and the fifth grid are pasted on the substrate by an adhesive.
[0011] In the utility model, grids with different lengths are provided and connected in parallel. The corresponding resistance values of the grids with different lengths are also different. It is convenient to use a laser to break one or more grids, so as to flexibly adjust the corresponding resistance value, and the operation is more convenient. The resistance value is adjusted by the laser. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Figure 1 is a connection schematic diagram of the utility model;
[0013] Figure 2 is a state schematic diagram of laser breaking of the utility model.
[0014] REFERENCE SIGNS:
[0015] Substrate 1, first pad 2, second pad 3, first grid 4, second grid 5, third grid 6, fourth grid 7, fifth grid 8, first connecting member 9, second connecting member 10. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0016] The embodiments of the present utility model will be described in detail below. Examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary only for explaining the present utility model and should not be construed as limiting the present utility model.
[0017] In the description of the present utility model, it should be understood that if there are terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present utility model, "a plurality of" means two or more, unless otherwise specifically defined.
[0018] In the description of the present utility model, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection. It may be a mechanical connection or an electrical connection. It may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0019] As Figure 1 shown, a strain gauge with a parallel structure capable of realizing laser trimming resistance includes a substrate 1, on which a first pad 2 and a second pad 3 are provided, as well as a first grid 4, a second grid 5, a third grid 6, a fourth grid 7, and a fifth grid 8 with different lengths. The first pad 2 is connected to the first grid 4, the first grid 4 is connected in parallel with the second grid 5, the second grid 5 is connected in series with the third grid 6, the third grid 6 is connected in series with the fourth grid 7, the fourth grid 7 is connected in parallel with the fifth grid 8, and the fifth grid is connected to the second pad. The lengths of the respective grids are different, and the corresponding resistance values are also different, so that different resistance values can be flexibly formed.
[0020] The lengths of the first grid, the second grid, the fourth grid, and the fifth grid are all smaller than the length of the third grid. Centered on the third grid, the first grid and the second grid are symmetrically distributed with the fourth grid and the fifth grid.
[0021] A first connecting member 9 is disposed between the first pad 2, the first wire grid 4 and the second wire grid 5, and the first connecting member 9 is respectively connected to the first pad 2, the first wire grid 7 and the second wire grid 8; a second connecting member 10 is disposed between the second pad 3, the fourth wire grid 7 and the fifth wire grid 8, and the second connecting member 10 is respectively connected to the second pad 3, the fourth wire grid 7 and the fifth wire grid 8. The first connecting member and the second connecting member are both electrical components and play a role in electrical conduction.
[0022] The base is made by coating, rotating and spraying with polyimide resin or modified phenolic resin or polyether ether ketone or epoxy resin or glass fiber reinforced resin. The first wire grid, the second wire grid, the third wire grid, the fourth wire grid and the fifth wire grid are pasted on the base by an adhesive.
[0023] The utility model is convenient to adjust the resistance value by means of laser interruption. According to the required usage place, a plurality of first wire grids, second wire grids, third wire grids, fourth wire grids and fifth wire grids are set. By using the parallel connection relationship between the wire grids, when the resistance value needs to be adjusted, refer to Figure 2 As shown, for example: when producing a strain gauge of 350 ohms, the etched one is only 320 ohms. To adjust it to 350 ohms, a corresponding 30-ohm wire grid or 2 or multiple parallel wire grids with a sum of 30 ohms can be laser-interrupted to change the resistance value, and finally a product of 350 ohms can be obtained. Laser interruption can be performed on the second connecting member to make some of the wire grids not be connected, so as to achieve convenient adjustment.
[0024] It should be noted that the above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. Although the present utility model has been described in detail with reference to the embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. However, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.
Claims
1. A strain gauge with a parallel structure capable of realizing laser resistance adjustment, comprising a substrate, characterized in that: The substrate is provided with a first soldering pad and a second soldering pad, as well as a first wire grid, a second wire grid, a third wire grid, a fourth wire grid and a fifth wire grid of different lengths. The first soldering pad is connected to the first wire grid, the first wire grid is connected to the second wire grid in parallel, the second wire grid is connected to the third wire grid in series, the third wire grid is connected to the fourth wire grid in series, the fourth wire grid is connected to the fifth wire grid in parallel, and the fifth wire grid is connected to the second soldering pad.
2. The parallel structure strain gauge capable of realizing laser resistance adjustment according to claim 1, characterized in that: The lengths of the first wire grid, the second wire grid, the fourth wire grid and the fifth wire grid are all shorter than the length of the third wire grid.
3. The parallel structure strain gauge capable of laser resistance adjustment according to claim 1, characterized in that: With the third wire grid as the center, the first wire grid, the second wire grid, the fourth wire grid and the fifth wire grid are symmetrically distributed.
4. The parallel structure strain gauge capable of laser resistance adjustment according to claim 1, characterized in that: A first connecting member is arranged between the first solder pad, the first wire grid and the second wire grid, and the first connecting member is respectively connected to the first solder pad, the first wire grid and the second wire grid; a second connecting member is arranged between the second solder pad, the fourth wire grid and the fifth wire grid, and the second connecting member is respectively connected to the second solder pad, the fourth wire grid and the fifth wire grid.
5. The parallel structure strain gauge capable of realizing laser resistance adjustment according to claim 1, characterized in that: The substrate is formed by coating, rotating or spraying polyimide resin or modified phenolic resin or polyetheretherketone or epoxy resin or glass fiber reinforced resin.
6. The parallel structure strain gauge capable of realizing laser resistance adjustment according to claim 1, characterized in that: The first wire grid, the second wire grid, the third wire grid, the fourth wire grid and the fifth wire grid are adhered to the substrate by adhesive.