SU503153A1 - Transducer to electrical signal - Google Patents

Description

one

The invention relates to a measurement technique for converting mechanical displacements into electrical quantities.

Transducers to electrical signals are known in which a Hall sensor is used as a sensing element.

In such devices, the Hall sensor mechanically moves in a non-uniform magnetic field, and e. d. The sensor depends on the magnitude of the displacement. The Hall sensor can be mechanically coupled to a pressure sensitive element. Then the Hall sensor converts the pressure into a DC voltage. In such pressure transducers, the Hall sensor is typically placed in the magnetic field of a massive magnet.

Sensitivity to voltage (expressed in volts per millimeter of mechanical displacement) is one of the characteristics of such a pressure indicator. Voltage Sensitivity is recorded as follows:

Y YiY2,

where Yi (sensitivity sensor Holv

la, expressed in volts per gauss);

Y2 - (magnetic field gradient, exp-V

gauss by 1 mm).

A slight sensitivity in such a pressure transducer Y St per mm /

in particular, with the impossibility of obtaining a large magnetic field gradient using magnets of conventional design.

On the other hand, using a massive magnet to create a non-uniform magnetic field in this pressure transducer does not allow, despite the small dimensions of the Hall sensor itself, to reduce the size of the entire device.

In order to increase sensitivity and reduce the dimensions in the proposed converter, each part of the magnetic circuit is made in the form of a magnetized magnetic film mounted on a dielectric substrate, while the Hall sensor is made of film and is connected to one of the magnetic films of the magnetic circuit rigidly, and the other magnetic film is connected through an elastic gasket .

The drawing shows the general view of the onisable transducer, section.

The converter contains a film Hall sensor 1, which is rigidly connected to the magnetic film 2, which is on a flat dielectric substrate 3. Elastic gasket 4 is glued with one surface to the Hall sensor 1, and the other surface to the magnet film 5 located on the dielectric substrate 6. The wire leads 7 and 8 are soldered to the current contacts of the Hall sensor I.

As magnetic films 2 and 5, for example, monocrystalline films of cobalt ferrite deposited on magnesium oxide substrates can be used. Hall sensor 1 can be made, for example, of InSb by thermal spraying in a vacuum. Elastic gasket 4 can be made, for example, of rubber and glued to the Hall sensor I and the magnetic film 5.

The thickness of the elastic gasket 4 is chosen so that the dependence of e. d. The Hall sensor 1 from the displacement of the magnetic films 2 and 5 relative to each other in a certain interval turned out to be linear.

After the converter is assembled, the magnetic system (magnetic core) must be magnetized in a field not less than five times the coercive force of magnetic films 2 and 5. The direction of the magnetizing field must coincide with the normal to the plane of magnetic films 2 and 5.

The device works as follows. The measured pressure causes a parallel mechanical displacement of the magnetic films 2 and 5 relative to each other, which leads to a change in the magnetic field acting on the Hall sensor I, and consequently changes

value a. d. Hall sensor. When the elastic pressure is removed, the gasket 4 returns the device to its original state.

Use in converter containing generator e. d. the Hall sensor, film magnetic system leads, on the one hand, to a reduction in the size of the device and, on the other hand, it allows to obtain a magnetic field gradient 1-2 times higher,

than it is possible to do with the help of massive magnets, which allows increasing the voltage sensitivity by 1-2 times.

Form; and invention

15

A transducer to an electrical signal, mainly for pressure meters, comprising a Hall sensor located between two parts of the magnetic circuit, characterized in that, in order to increase the sensitivity and reduce the size, each part of the magnetic circuit is in it.

made in the form of a magnetized magnetic film, mounted on a dielectric substrate, while the Hall sensor is made of a film and is rigidly connected with one of the magnetic films of the magnetic core, and connected with another magnetic film through an elastic gasket.

eight