Small displacement sensing method and device

Abstract

The invention relates to a small displacement sensing method and apparatus, which relate to a measuring method and apparatus for displacement, temperature and strength.The invention sets deformation medium with some electrical resistance between two electric conductors, the bulk of which changes with the change of measured displacement, leading to the change of said deformation medium electric conductor. The required displacement parameter will be get through measuring the change of said deformation electric resistance between two electric conductors.

Description

technical field

[0001] The invention relates to a method and device for measuring physical quantities such as displacement, temperature and strength, in particular to a small displacement sensing method and device. Background technique

[0002] The existing displacement sensing methods mainly include the following types: 1. Metal wire film or patch is used. Although this method is mature and cheap, it can only measure the strain, so it is also called strain gauge. Usually the finished component size cannot be too small. 2. The thin film based on silicon material is used to measure the strain, and the silicon material itself needs a protective device. It can be made very small, but the cost is very high. 3. The optical fiber sensing method, which measures the strain through the optical change caused by the deformation of the material, requires a CCD imaging element, and the cost is also very high. 4. Resistance ruler, which is a very high-precision length measurement metho...

Examples

Embodiment 1

[0021] See figure 1 A deformation medium 3 with a certain resistance value is defined between the two conductors 1 and 2. The deformation medium 3 can be a liquid or colloidal medium, or other media that can deform, such as a sponge with resistance value bodies or other deformable media. The volume size of the deformable medium 3 changes with the change of the measured displacement, resulting in a change in the resistance value of the deformable medium 3, and measuring the change in the resistance value of the deformable medium between two conductors can obtain the measured value. Measure displacement parameters. The two conductors 1 and 2 can be flat electrodes with a certain area, and the other surfaces of the two electrode plates 1 and 2 are electrically connected with a resistance measuring device 4 . The measured displacement is the longitudinal distance a between the two conductors in this embodiment, and the change of the longitudinal distance a between the two conduc...

Embodiment 2

[0024] See figure 2 , The outer surface of the deformable medium 3 between the two electrode plates 1, 2 may be provided with a restricting piece 5, which in this embodiment is two restricting blocks 5, and the restricting block 5 is an insulator. The material selection and limitation of the deformable medium 3 are the same as those in Example 1, except that the measured displacement is the transverse direction between the two limiting blocks arranged between the two conductors 1 and 2 to limit the radial displacement of the deformable medium 3. distance b. The change of the lateral distance between the two limiting blocks 5 causes the cross-sectional area of ​​the deformable medium 3 resistor between the electrodes to change, which in turn causes the resistance value to change inversely proportional to the lateral distance, see the calculation formula of embodiment 1 (the present embodiment The lateral distance b may be the lateral distance S) in the formula. The measured ...

technical field

[0001] The invention relates to a method and device for measuring physical quantities such as displacement, temperature and strength, in particular to a small displacement sensing method and device. Background technique

[0002] The existing displacement sensing methods mainly include the following types: 1. Metal wire film or patch is used. Although this method is mature and cheap, it can only measure the strain, so it is also called strain gauge. Usually the finished component size cannot be too small. 2. The thin film based on silicon material is used to measure the strain, and the silicon material itself needs a protective device. It can be made very small, but the cost is very high. 3. The optical fiber sensing method, which measures the strain through the optical change caused by the deformation of the material, requires a CCD imaging element, and the cost is also very high. 4. Resistance ruler, which is a very high-precision length measurement metho...

Examples

Embodiment 1

[0021] See figure 1 A deformation medium 3 with a certain resistance value is defined between the two conductors 1 and 2. The deformation medium 3 can be a liquid or colloidal medium, or other media that can deform, such as a sponge with resistance value bodies or other deformable media. The volume size of the deformable medium 3 changes with the change of the measured displacement, resulting in a change in the resistance value of the deformable medium 3, and measuring the change in the resistance value of the deformable medium between two conductors can obtain the measured value. Measure displacement parameters. The two conductors 1 and 2 can be flat electrodes with a certain area, and the other surfaces of the two electrode plates 1 and 2 are electrically connected with a resistance measuring device 4 . The measured displacement is the longitudinal distance a between the two conductors in this embodiment, and the change of the longitudinal distance a between the two conduc...

Embodiment 2

[0024] See figure 2 , The outer surface of the deformable medium 3 between the two electrode plates 1, 2 may be provided with a restricting piece 5, which in this embodiment is two restricting blocks 5, and the restricting block 5 is an insulator. The material selection and limitation of the deformable medium 3 are the same as those in Example 1, except that the measured displacement is the transverse direction between the two limiting blocks arranged between the two conductors 1 and 2 to limit the radial displacement of the deformable medium 3. distance b. The change of the lateral distance between the two limiting blocks 5 causes the cross-sectional area of ​​the deformable medium 3 resistor between the electrodes to change, which in turn causes the resistance value to change inversely proportional to the lateral distance, see the calculation formula of embodiment 1 (the present embodiment The lateral distance b may be the lateral distance S) in the formula. The measured ...

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