Interdigitated metal strain gauges in five sensitive grids distributed laterally

Abstract

The invention discloses a transverse distribution five-sensitive-grid center interdigital metal strain gage capable of measuring transverse partial derivatives of the centers of unilateral dual-offset sensitive grids. The metal strain gage comprises a substrate and five sensitive grids fixed to the substrate. The two ends of each sensitive grid are each connected with a pin, each sensitive grid comprises a sensitive section and a transitional section, and the axes of all the sensitive sections are parallel straight lines in the same plane. In the plane, the axial direction refers to the direction along the axes, and the transverse direction refers to the direction perpendicular to the axial direction. The centers of the five sensitive grids do not have deflection in the axial direction and have deflection in the transverse direction. All the sensitive grids comprise a sparse sensitive grid, a middle sensitive grid A, a middle sensitive grid B, a dense sensitive grid A and a dense sensitive grid B from top to bottom in the transverse direction in the sequence of the central positions of the sensitive grids. The two middle sensitive grids and the two lower sensitive grids are arranged in an interdigital mode, and the total resistance variation values of all the sensitive grids under the same strain are 1 to 4 to 4 to 3 to 3. According to the metal strain gage, time sharing multiplex is conducted on the sparse sensitive grid, and the strain transverse first-order partial derivatives of the centers of the dense sensitive grid A and the dense sensitive grid B can almost be measured at the same time.

Description

technical field [0001] The invention relates to the field of sensors, in particular to a metal strain gauge. Background technique [0002] The working principle of the metal resistance strain gauge is the resistance strain effect, that is, when the metal wire is subjected to strain, its resistance changes correspondingly with the magnitude of the mechanical deformation (stretch or compression). The theoretical formula for the resistance strain effect is as follows: [0003] [0004] Where R is its resistance value, ρ is the resistivity of the metal material, L is the length of the metal material, and S is the cross-sectional area of ​​the metal material. During the process of mechanical deformation of the metal wire under strain, ρ, L, and S will all change, which will inevitably cause changes in the resistance value of the metal material. When the metal material is stretched, the length increases, the cross-sectional area decreases, and the resistance value increases; ...

AI Technical Summary

Problems solved by technology

[0013] In order to overcome the deficiency that the existing metal strain gauges cannot detect the strain deflection, the present invention provides a lateral deflector that can measure the lateral deflection of the surface strain and can measure the lateral deflection of the center of the single-side double-biased sensitive grid. Distributing interdigitated metal strain gauges in the five sensitive grids, especially for measuring the lateral first-order partial conductance of the corners and edges of the workpiece where the size of the strain gauges is restricted.

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