It can measure the axial deviation of the axial deflection of the outer axial deflection of the offset sensitive grid. Three sensitive grid interdigitated metal strain gauges

Abstract

An axial-deviation three-sensitive-grid interdigital metal strain gauge capable of measuring an outside axial partial derivative of a bias sensitive grid comprises a substrate and three sensitive grids fixed to the substrate. Each sensitive grid includes a sensitive segment and a transition segment. Axes of all the sensitive segments are straight lines which are arranged in parallel and are in a same plane. In a plane determined by the axes of the sensitive segments, an axial direction is along an axis direction of the sensitive segments and a horizontal direction is vertical to the axial direction. Center axes of the three sensitive grids are biased along an upward direction and are not biased along the horizontal direction. The three sensitive grids are a left sensitive grid, a middle sensitive grid and a right sensitive grid along the axial direction from left to right according to a sensitive grid center position sequence. First two and last two sensitive grids are arranged in an interdigital mode. Total resistance change values of the sensitive segments of the left sensitive grid, the middle sensitive grid and the right sensitive grid under a same strain are 3 to 8 to 5. The strain gauge can detect that a distance from a right outer side of the right sensitive grid to a right sensitive grid center equals to a strain axial first order partial derivative at a center spacing of the middle and right sensitive grids.

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 deflector, the present invention provides an axial deflector that can measure the axial deflection of the outer side of the bias sensitive grid, which can not only measure the strain but also effectively detect the axial deflector of the surface strain. The deviation three-sensitive grid cross refers to the metal strain gauge, especially for measuring the corners and edges of the workpiece where the size of the strain gauge is limited or other axial first-order deflectors that are not suitable for the location of the strain gauge.

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