SU1411567A1 - Device for contactless check of object position - Google Patents

Abstract

The invention relates to a measurement technique and can be used for non-contact monitoring of the position of an object. The purpose of the invention is to improve the control accuracy, it is achieved by forming the output signal of the comparison circuit 10, which coincides in phase with the reference voltage when the object 16 reaches a predetermined position, which is determined by the adjustable voltage division 9 setting, which ensures the specified phase shift. between electrodes 3 and 4. 1 c.p. f-ly, 1 ill.

Description

g

S

(/;

ate

about:

The invention relates to a measurement technique and can be used for econtact control of the position of an object.

The purpose of the invention is to improve the control accuracy by forming the output-south signal coinciding in phase with the reference voltage at the moment when the object under control is in a given position.

I The drawing shows a block diagram of a device for contactless monitoring of the position of an object.

I The device contains a sensor 1, consisting of a complanarly located zero-focusing 2 and potential 5 electrodes and a disk measuring electrode 4 placed in the center of the electrode 2 and 3, ring shielding electrodes 5, a generator of 6 harmonic oscillations connected to to the focusing electrode 2, the first 7 and second 8 phase-shifting links connected in series and the adjustable divider 9 of the voltage, the output of which is connected to the potential electrode 3, and the comparison circuit 10 consisting of the first 11 and the second 12 zero organs, whose inputs, which are the inputs of the comparison circuit 10, are connected respectively to the output of the first phase-rotating link 7 and the measuring electrode 4, from the first 13 and second 14 differentiating chains, the inputs connected to the outputs of the first 11 and second 12 zero-organov, respectively, and circuits 15, the inputs of which are connected to the outputs of the differentiating chains 13 and 14, and the output is the output of the comparison and device 10.

I The device operates as follows.

From the output of the generator b, the alternating voltage is applied to the focusing electrode 2 of the sensor 1, and to the potential electrode 3 the same voltage, but shifted in phase by 90 ° through two phase-shifting links 7 and 8, is fed through a divider 9 tension

In this case, in the air gap between the sensor 1 and the surface of the controlled object 16, an alternating electric field is created, which is a superposition of .leii. created by each of the electrodes of the sensor 1 separately. As a result, the instantaneous value of the induced potential of the measuring electrode 4 is determined by the AB. Sum of the potentials of the two electrodes 2 and 3 on it.

Since the alternating voltages applied to electrodes 2 and 3 differ in phase by 90 °, in

0

If their amplitudes are equal, the information signal has a phase shift equal to 45 °, i.e., exactly the same as the reference signal supplied from the output of the generator 6 through the first phase switch 7 to the second input of the comparison circuit 10. Therefore, a short voltage pulse is formed at the output of the latter, the leading edge of which coincides in time with the instant the controlled object is at a given distance from the measuring sensor, and the use of circuits 13 and 14 which narrow the output pulses of the zero organs 11 and 12 gaps during the formation of output pulses of the device.

Claims (2)

1. A device for contactless control of an object's position, containing a sensor consisting of coplanarly arranged ring focusing and potential electrodes and a disk measuring electrode placed in the center of ring electrodes separated by ring shielding electrodes, a harmonic oscillator, the output of which is connected to focusing electrode, and a comparison circuit, one of the inputs of which is connected to a measuring electrode, characterized in that, in order to increase the control accuracy, It is equipped with series-connected two phase-changing links 1 1i, the input of the first of which is connected to the generator, and the output to the second input of the comparison circuit, and an adjustable voltage divider, the output of which is connected to the potential electrode of the sensor. 2. A device according to claim 1, characterized in that the comparison circuit is made in the form of two null organs, the outputs of which are 0 inputs of the comparison circuit, two differentiating chains connected at the outputs of the zero-organs, and a coincidence circuit whose inputs are connected to the outputs of the differentiating chains, and the output is the output of the comparison circuit. 0