RU127901U1 - DIFFERENTIAL-TRANSFORMER LINEAR MOVEMENT SENSOR - Google Patents

Abstract

A differential transformer linear displacement sensor containing coaxially located working half-windings, an excitation winding and a movable ferromagnetic core enclosed in an external magnetic circuit, characterized in that the calculated ratio of the number of turns of the working half-windings to the excitation winding is ensured by the incomplete last layer of the excitation winding uniformly distributed over the length of the coil.

Description

The utility model relates to the field of electromechanics and instrumentation and can be used in control systems of various objects, including aircraft.

Known differential transformer linear displacement sensors, containing coaxially located concentrated [4] or stepwise located working half-coils [1-3], an excitation coil wound coaxially under or above the working half-coils and located inside the coils of a ferromagnetic core enclosed in an external ferromagnetic magnetic circuit - body.

The sensors are simple in design, technologically advanced to manufacture, reliable and easy to operate.

However, they have a number of significant drawbacks.

One of them is the spread of the steepness of the output voltage from sample to sample, determined mainly by the spread of the number of turns in the windings and, as a result, the spread of the ratio of the number of turns of the field winding to the working W ₁ / W ₂ .

To reduce the non-linearity of the output voltage of the sensor, the windings are wound in tight layers round to round, but due to the variation in the diameters of the wires, the number of turns in the full layers differs from the rated-rated one, which leads to a slope deviation of up to 5% or more.

In the proposed utility model, the working half windings W ₂ and the field winding W _{1 are} also wound tightly to the coil except for the last layer of the field winding located coaxially above the working half windings.

In the last layer, there are fewer turns that are evenly distributed along the length of the coil. Their number is determined from a given transformation ratio W ₁ / W ₂ .

The technical result consists in the use of an incomplete, evenly distributed last layer with an estimated number of turns, which allows to reduce the variation in the steepness of the output voltage of the sensor from 5% to less than 1% determined mainly by the variation in the magnetic characteristics of the magnetic cores, the size of the air gap between the external magnetic core and the inner - movable core

The sensor includes working semi-windings 5 and excitation coil 3, 4 located coaxially above them and located on a frame made of non-magnetic insulating material 7. The last, upper layer of field winding 4 has a reduced number of turns calculated for each specific sample that are evenly distributed along the length of the frame coil , with windings through insulation 2 is placed in the outer magnetic circuit 1.

Inside the sensor is a movable ferromagnetic core 6.

Literature

1. A.Kh.Shidlovich Differential transformers and their application. L .: Energy, 1966.

2. Copyright certificate No. 1569525, 06/07/90, BI No. 21.

3. Copyright certificate No. 1348632, 10.30.87, BI No. 40.

4. Patent for utility model No. 85448, 08/10/2009, BI No. 22.

5. French patent dated 03/27/87 No. 2587.795 Inductive linear displacement sensor.

Claims (1)

A differential transformer linear displacement sensor containing coaxially located working half-windings, an excitation winding and a movable ferromagnetic core enclosed in an external magnetic circuit, characterized in that the calculated ratio of the number of turns of the working half-windings to the excitation winding is ensured by the incomplete last layer of the excitation winding uniformly distributed over the length of the coil.

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