Axially distributed five-sensitive grid side interdigitated metal strain gauges that can measure the axial deflection of the outer side of the double-sided biased sensitive grid

Abstract

The invention relates to an axially-distributed five-sensitive-grid-edge interdigital metal foil gauge for measuring axial partial derivatives outside a double side bias sensitive grid. The metal foil gauge comprises a substrate and five sensitive grids fixed on the substrate, wherein each sensitive grid includes a sensitive section and a transition section; the axes of all the sensitive sections are parallel lines in the same plane; in the plane, the direction along the axis is the axial direction, and the direction being perpendicular to the axial direction is the transverse direction; the axial directions between the centers of five sensitive grids have deviation and the transverse directions between the centers of five sensitive grids have no deviation; the five sensitive grids are a sparse-A sensitive grid, a sparse-B sensitive grid, an intermediate sensitive grid, a c sensitive grid, a dense-A sensitive grid and a dense-B sensitive grid in the transverse direction from top to bottom according to the sequence of the center positions of the five sensitive grids; according to the positions of the centers of all the sensitive grids, in the axial direction, from left to right, all the sensitive grids are respectively a left fifth sensitive grid and a left third sensitive grid, and then an intermediate sensitive grid, and then a right third sensitive grid and a right fifth sensitive grid; the left two sensitive grids and the right two sensitive grids are mutually arranged in the interdigital way; the proportion of the total resistance variation values for the five sensitive grids under the same strain is 5:3:8:3:5; and time division multiplex access of the intermediate sensitive grid is performed. The axially-distributed five-sensitive-grid-edge interdigital metal foil gauge can measure the strain axial first order partial derivatives at a center at the same time, wherein the distance from the left and right sides of the centers of the left fifth sensitive grid and the right fifth sensitive grid to the center is equal to the distance from the center to the center of the intermediate sensitive grid.

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 device that can measure the axial deflection of the outer side of the bias sensitive grid that can measure the strain and can effectively detect the axial deflection of the surface strain. Axial distribution of metal strain gauges with five sensitive grid edges, especially for the measurement of 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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