SU127923A1 - Linear-to-Voltage Transformer Converter - Google Patents

Description

In electromechanical structures used in automatic control systems and remote control systems, it is often necessary to convert the sum and difference of several mechanical displacements into electrical voltage and current.

With the help of an appropriate sensor, mechanical and displacement is converted into an electrical parameter (active and reactive resistance, voltage, capacitance, etc.), and it is necessary that the linear dependence be observed, between the mechanical displacement value and the variation of the electrical parameter.

The described device provides this condition and differs from known induction sensors in that EI is provided with a setting of "zero at any point on the scale and an indication of zero crossing by changing the sign of the output voltage, as well as the linearity limit.

There are one or several zero-setting coils on the medium-m shaft of the U-shaped magnetisable guide, the windings of which are connected in series and counter with the windings of the corresponding number of measuring coils.

The drawing shows a diagram of a transformer linear displacement transducer into an adjustable electrical voltage.

The main element of the device is a transformer /, whose magnetic transducer is made of electrical steel with high magnetic permeability at low voltages of the magnetic field. The transformer iron is W-shaped with high rods and is open at the top. On the middle core of the transformer is placed the excitation coil 2, which is powered by a special

Or 127923-2 traxformator or directly from the network. The pivot coil 3, mechanically connected with the object being moved, can move along the rod, occupying a position between coil 4 and a certain limit level, on which deviation from the line r begins to affect; the south law of induction change is thanks to the excitability of the coil 2.

Coils 3 "4 are connected in series and in such a way that the emf, podoody variable magnetic flux in the turns of the movable coil 4, is sent towards the emf induced in the turns of the movable coil 3. In the catup: ek on) circuit, the measuring voltmeter 5.

With the same number of turns in coils 3 and 4, and when these coils are located at the level of nair, the jelly at the terminals of the device 5 is zero. When coil 3 moves down, the electromotive force, which is induced in its coils, increases, and terminal Ia.x of device 5 appears as a voltage equal to the difference of emf. coils 5 and 4.

The alignment of the moving and stationary coils on the same level (zero point of the device) is achieved by winding the coils in the form of thin frames, the turns of which when combined the coils are distant from the level separating them 1-1 or 11 on the full turn.

Another way of combining coils 3 to 4 is not one level; that the stationary roller is made in the form of a thin layer of vitcoses, tightly covering the rod, and the mobile coil 3 has a somewhat larger size and when the coils are positioned at the same level, the stationary coil is outside. In the next case, the stationary coil can be located in the middle of the rod, and then the movement of the moving coil will fix a linear return from some predetermined level in both directions. The magnetic flux from the middle rod passes into the side rods through the air. When you: the magnetic permeability of an etal, its magnetic resistance is so small compared with the resistance of the air gaps that the drop in magnetic voltage on the sections of the magnetic conductor formed by steel is negligible and, consequently, the drop in magnetic voltage in the air gaps is constant the value along most of the length of the core bars of a formator. Under these conditions, in the air gaps, the magnetic induction maintains a constant value over large parts of the length of the rods and the field is uniform.

Owing to the constant values of induction B of air gaps, the magnetic flux, which directs the cross section of the middle rod, decreases evenly along its length, and if the moving coil 3 consisting of several isolated turns of wire is attached to the middle rod of the transformer, then the emf , induced by a variable magnetic field in the turns of this roller, will be linear; depending on the distance Db, which is measured from some initial position of the roller on the rod.

With a linear dependence of induction in steel, there will be a constant value of induction in the air gap and, conversely, with a constant induction in the air gap, there will be a linear dependence in the steel.

Subject invention

A linear-to-electrical transformer converter with an excitation coil and a movable measuring transducer, so that with the aim of providing

“set zero” at any point of the scale, indicating passage through zero by changing the sign of the output voltage and extending the linearity limits, it contains one or more fixed zero-setting coils on the middle shaft of the W-shaped magitopath, the windings of which are connected in series and opposite to the windings the corresponding number of measuring coils.

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