SU1231394A1 - Variable-capacitance transducer - Google Patents

Abstract

The invention relates to a measuring instrument and a technician and can be used to control the flatness of metal surfaces, providing an increase in reliability by preventing uneven wear of the electrodes. The converter contains a case with electrodes fixed in it and a dielectric plate with through holes, which can be installed at a predetermined distance from the body with the help of three micrometric and three spring-loaded limiting screws. This provides the desired depth of the electrodes in the holes of the plate. The end surfaces of the electrodes form a reference plane. By alternately measuring the electrical capacitance of the capacitors formed by the electrodes and the surface to be controlled, the flatness of the latter is judged. The installation of electrodes with a hollow in the plate prevents premature and uneven wear of the end surfaces of the electrodes. 3 il. I (L

Description

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The invention relates to a measuring technique and can be used to control the flatness of the surfaces of parts made of metal.

 The purpose of the invention is to increase the reliability of the converter by preventing non-uniform wear of the electrodes.

Figure 1 presents the Converter, a General view; Figures 2 and 3 show installation options for the transducer on the monitored surfaces during the measurement process.

A capacitive transducer for controlling the flatness of the metal surface includes a housing 1, measuring electrodes 2 rigidly fixed therein, whose end surfaces form a reference plane 3, and a plate 4 with through holes for inserting electrodes 2 into them. The plate 4 is elastically connected to the housing 1 and is installed with the possibility of adjusting its position relative to the housing by means of springs 5,: three micrometric screws 6 and three restrictive screws 7. The terminals 8 connect the electrodes 2 through a switch to measuring circuit (not shown). The support surface 9 of the plate 4 is made with the same machining accuracy as the reference plane 3, and is intended to be mounted on the test surface 10,

The Converter operates as follows.

The support surface 9 of the transducer is placed on the test surface 10 (FIGS. 2 and 3). Under the weight of the body 1 with electrodes

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2 goes down, compressing the spring 5 and providing the required penetration of the electrodes 2 into the openings of the plate 4. When checking for rough surfaces

5, the deepening of these electrodes is advisable to shrink to a smaller depth to prevent damage (wear) of the end surfaces of the electrodes 2 (Fig. 2). When controlling the precision surfaces 10, the reference plane 3 can be aligned with the supporting surface 9 (Fig. 3) of the plate 4. If necessary, the screws 6 and 7 can be set to

15 allows the plate 4 to be fixed motionless relative to the housing 1. After mounting the converter, the capacitances of the capacitors formed by the electrodes 2 and

20 surface controlled product LIA. These capacitors are switched by a switch into the feedback circuit of an operational amplifier. The flatness of the test surface is su25 d t by comparing the measured capacitance values.

Formula image

30 capacitive transducer for

control the flatness of the metal surface, comprising a housing and electrodes rigidly fixed in the housing, the end surfaces of which

35 form a reference plane, characterized by the fact that, in order to increase reliability, it is provided with a plastic made of dielectric material with end-to-end fittings for the electrodes, which is elastically connected to the body and is adjustable in position relative to the body.

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Editor A. Ogar

Compiled by L. Guskov

Tehred: I.Popovich Proofreader S.Shekmar

Order 2556/47 Circulation 670 Subscription

VNIIPI USSR State Committee

for inventions and discoveries P3035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

Claims (1)

Claim 30 Capacitive transducer for monitoring the flatness of a metal surface, comprising a housing and electrodes rigidly fixed in the housing, the end surfaces of which 35 form a reference plane, characterized in that, in order to increase reliability, it is provided with a plate made of a dielectric material with through holes for electrodes 40, elastically connected to the housing and installed with the possibility of regulating its position relative to the housing. FIG. 1 Figure 2 <Riga.Z