SU1231387A1 - Device for measuring linear displacements - Google Patents

Abstract

The invention relates to a measurement technique and makes it possible to increase the sensitivity of a device for measuring linear displacements, which contains a transformer sensor with a bark in the form of alternating electrically conductive and ferromagnetic. The sensor also contains the primary winding and two sections of the secondary winding placed symmetrically on opposite sides of it. To the point of connection of the sections of the secondary winding there is a movable contact of a potentiometer connected by extreme points to a power source. An adjustable resistor is connected in series with the primary winding. A phase meter is connected to the secondary side of the secondary winding. When the core is moved, the magnitude and phase of the voltage on the upholstery of the transformer sensor change simultaneously. The resultant phase difference of the signals at the phase meter inputs changes when the core is moved by 720. Thanks to pacnm the output signal range, if the core is moved the same, the sensitivity of the device is increased. 2 Il. (L S ao oo with 00

Description

The invention relates to information-measuring technology and can be used to measure large linear displacements of various objects.

The purpose of the invention is to increase the sensitivity of the device.

Fig. 1 shows a conventional structural diagram of a device for measuring linear displacements in Fig. 2, a graph of the variation of the amplitude and phase of a voltage on one of the secondary sections of the displacement sensor, depending on the movement of its core.

The device contains a transformer displacement sensor t with a rod core 2 in the form of alternating ferromagnetic portions 3 and electroconductive portions located between them 4, coaxially. with the core core 2, the primary winding 5 and sections 6 and 7 of the secondary winding of sensor 1 are placed, sections 6 and 7 are connected in series with each other and are located on either side of the primary winding 5. A variable power supply 8 is connected to one of the primary windings current directly, and between the other output winding. 5 and this source, an adjustable resistor 9 is connected. A potentiometer 10 is connected to the terminals of the power supply source 8, the movable contact of which is connected to the junction point of sections 6 and 7 of the secondary winding of sensor 1. The phase meter is connected to the free ends of sections 6 and 7 of the secondary winding eleven.

A device for measuring linear displacements operates as follows.

When moving the core 2, the losses due to the influence of the electrically conductive parts 4 of the core 2, and the magnetic conductivity in the magnetic flux paths created by the primary winding 5 of the sensor 1 change.

As a result, the magnitudes of the active and inductance resistances introduced into its circuit and the phase angle between the supply voltage and the winding current 5 are changed. The angle sp of the phase shift is a periodic function of the magnitude of the linear displacement X cor 2 (Fig. 2). The period of its change is equal to the step T of the alternation of the electroconductive and ferromagnetic regions to

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p 2. The phase shift angle reaches a minimum when the core moves from the initial position shown in the drawing, by the size of a quarter of a step Tj and the maximum when it moves by 3/4 T. The minimums (maxima) introduced into the winding circuit 5 correspond to these positions. active and inductive resistances.

The movement of the core 2 also leads to a periodic change in the amplitude: the magnetic flux penetrating sections 6 and 7 of the secondary winding of the sensor 1. The minimum amplitude of the magnetic flux through them is achieved when the electrically conductive sections are 4 cor. 2 between the primary winding 5 and sections 6 and 7 of the secondary round b roll, which in FIG. 2 corresponds to the points O and T along the abscissa. The maximum amplitude of the magnetic flux passing through sections 6 and 7 is reached when the electrically conductive sections 4 are at a remote position (points T / 2, 3/4, etc.).

In accordance with the phase and amplitude of the magnetic flux through sections 6 and 7, generated by the primary winding 5, the phase and amplitude E / {C induced in sections 6 and 7 change.

Phase vf these. EDT varies approximately sinusoidally depending on the displacement X, and the amplitude and sinusoidal law,. .

With the EMF of section 6, the auxiliary voltage at the movable contact of the potentiometer 10, is summed. and the output voltage of the flow voltage to the information input of the phase meter 11 a of the EMF of section 7 is subtracted from the auxiliary voltage on the moving contact of the potentiometer 10, and the resulting voltage is supplied to the reference input of the phase meter 11, due to a simultaneous change depending on the displaced X amplitude Ug and phase M g EMF sections 6 and 7 according to the specified laws, the phases of the resulting signals at the inputs of the phase meter change in opposite directions in proportion to the movement by +360 and -3.0 correspondingly when moving the core 2 to The value of alternating ferromagnetic and electrically conductive parts of the core 2 The resulting phase difference of the signals at the phase meter inputs changes by 720,

Adjusting the auxiliary voltage with the help of a potentiometer 10 and the minimum active resistance in the primary winding circuit 5 using a variable resistor 9 is necessary for the operability of the device in the presence of technological variation in the parameters of sensor 1.

As a result of the simultaneous effect of the displacement of the core on the phase and amplitude of the emf transformed into sections of the secondary winding, the range of output signal variation is increased with the same movement of the core, thereby providing a sensitivity increase of the device.

Claims (1)

Invention Formula A device for measuring linear displacements containing a transform 231387. four rotary displacement sensor with a bark in the form of a series of ferromagnetic and electrically conductive sections, the primary winding and two secondary-winding sections connected in series-counter to the sensor, and a power supply sensor connected to the primary 10 sensor winding whether it is tad; so that, in order to increase the sensitivity, the device is equipped with a potentiometer connected to the power supply, 15 the movable contact of which is connected to the junction point of the secondary winding sections, and a sequence connected. With the primary winding with an adjustable resistor, the measuring device is made in the form of a phase meter, the free end of one of the sections of the secondary winding is connected to its information input, and the free end of the other section to its reference input. I I I I Editor A.Orap Compiled by I. Kislycin Tehred V.-Kadar Proofreader V. But ha Zakae 2555/46 Circulation 670 Subscription ; VYUSHPI State Committee of the USSR for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4