Elastic wave pick-up device for reducing phase difference interference

Abstract

The invention relates to an elastic wave pick-up device for reducing phase difference interference. The device is composed of a metal support, a limit cassette, a rubber blanket, an elastic spring and a sensor screw. The limit cassette is painted with a special coupling agent and is inserted into the metal support. A sensor is inserted into the limit cassette. The rubber blanket and the elastic spring are put between the sensor and a cover body of the metal support. The metal support, the limit cassette, the elastic spring and the rubber blanket are successively installed in order and maintained to be concentric and parallel to each other. The part where the limit cassette and the metal support are contacted is filled with a coupling agent. The part where the sensor and the limit cassette are contacted is filled with a coupling agent. The sensor screw and the sensor are fixed as a whole, and the sensor screw's tip is ground to be arc-shaped. The invention has the following beneficial effects: through reducing contact area between the sensor and the test surface, phase difference interference generated by the sensor when the sensor picks-up elastic waves is reduced, and impact-echo pick-up precision is enhanced.

Description

technical field [0001] The invention belongs to the technical fields of detection and testing of machinery, civil engineering, metallurgy, etc., and in particular relates to an elastic wave pickup device for reducing phase difference interference. Background technique [0002] In the test of vibration and fluctuation, it is currently the most mainstream way to pick up the vibration signal of the structure under test by the sensor. Among them, the sensing system (including sensors and coupling methods) has a direct impact on the test signal. [0003] 1) The main characteristics of the sensor [0004] The main indicators of the sensor include quality, sensitivity, frequency response range, natural frequency, lateral sensitivity, temperature range, and impact resistance. Among them, the more important ones are: [0005] (1) The quality of the sensor: If the dynamic quality of the accelerometer is close to the dynamic quality of the measured structure, the vibration will be s...

AI Technical Summary

Problems solved by technology

[0011] (2) Fastening type: use bolts or hot melt glue to integrate the sensor and the test object. This method is the most tightly combined, but the workability and test efficiency are the worst;

[0018] (1) The test object has a large area and has high requirements for test efficiency;

[0019] (2) The measured body is generally non-magnetic;

[0020] (3) The surface of the measured body is generally rough, and there is moisture in many occasions;

[0044] (1) Because the sensitivity of the sensor is directly proportional to the quality of the sensor, when the sensor is replaced with a smaller sensor, the sensitivity of the sensor will also decrease;

[0045] (2) Reducing the contact area between the sensor and the test surface will reduce the coupling and the stability of the sensor, which is not conducive to receiving effective test signals

[0046] (3) Reducing the contact area between the sensor and the test surface may also cause excessive contact pressure, which will affect the natural frequency of the test system

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