SU428233A1 - SENSOR OF DYNAL1 EFFORTS - Google Patents

Description

The invention relates to the field of engineering and can be applied in the measurement of temporal forces in structures.

The well-known sensors of d.namatic amplifiers with piezo bai do not have sufficiently high sensitivity and do not have enough mex for wecKO and other information.

The proposed sensor differs from the known ones in that its body is made in the form of a package of three elastics, the middle of which is provided with through-holes with piezo-shake iketamn, the electrodes of which are connected by an annular bus.

Tajvoe sensor performance enhances its sensitivity and mechalic strength.

FIG. 1 shows the structure of the proposed sensor; on fayt. 2 - the scheme of his salutation in the site-kr.eileii.

The sensor consists of two identical metallic silas 1, clips 2, ring 5, has 1; Its sensor housing. In the case of 2, there are through holes - sockets in which packages of piezoceramic plastia (piezoelements) 4 are placed. In each packet of the elements, there is an electrode 5 of metal with a small modulus of elasticity, for example, lead or copper.

The piezoelectric elements 4 are closed on the electrode 5 with the same polarized surfaces. All electrodes 5 from each package of piezoelectric elements are closed on a common electrode B, the ends of which are led to connector 7, hermetically mounted on ring 3. The plates I are interconnected by rivets 8.

The tightness of the sensor is achieved due to the tight fit of the rivets 8 and the gaskets 9 and W made of rubber and installed between the ring 3 and the plate /.

The height of the package of piezoelectric elements 4 and electrode 5 is by an amount 01–0.02 mm greater than the height of casing 2. When assembling the sensor, due to the elastic deformation of electrode 5, the heights of the piezoceramic packages and casing are aligned. The total l stiffness of the package is significantly less than the rigidity of the metal plates 1 and the holder 2.

The different stiffness of the piezoceramic bags and metal plates reduces the loads acting on the piezoelectric elements of the sensor.

The sensor is mounted in the mount. The threaded connection is tightened according to the standards adopted for the design of the mechanism.

The sensor installed in this way during the operation of the object under study perceives the dynamic force coming to this mount point. This force increases or decreases the initial compressive strain of the piezoelectric elements and, as a result, the piezoelectric elements generate an electric charge proportional to the applied force.

The magnitude of the dynamic force perceived by the ground elements depends on the ratio of the stiffness of the piezoelectric elements and the sensor body. The ratio of these stiffnesses and the piezoelectric properties of the piezoelectric elements determine the sensitivity of the sensor, the value of which is determined by calibrating the sensor on a calibration stand having a reference source of dynamic force.

The electric signal of the same name from all the piezoelectric elements is summed at the common electrode and is fed to the output connector, from which it is then fed to a measuring device.

Depending on the size of the electrical signal taken from the sensor, it is possible to pre-amplify it before transmitting the signal to a measuring amplifier.

Subject invention

The dynamic force sensor, comprising a housing and piezoelectric bags with electrodes, characterized in that, in order to increase sensitivity and mechanical strength, the sensor body is made in the form of a package of three plates, the middle of which is filled with through holes these packages are piezo-washers, the electrodes of which are united by a common ring bus.

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