SU1335900A1 - Device for noncontact measurement of wire diameter - Google Patents

Abstract

The invention provides improved measurement accuracy. The device contains two microwave oscillators 1, 2, a directional coupler 3, an open resonator (PR) 4, made in the form of two coaxial reflectors, and an indicator 5. The frequency ratios of the microwave generators 1, 2 are chosen from the condition {, - - (j) C / 2U where L is the distance between coaxial reflectors; C is the speed of light. The microwave generators 1, 2 excite in OR 4 two “adjacent axial types of TEM oscillations. Indicator 5 captures the total coefficient. OP 4 transmissions associated with both modes of oscillation. If the measured wire 6 is placed in the center of the OP 4 coefficient. the transmission of the OR will be determined only by one TEM oscillation, since the "adjacent oscillation in the center of the OP 4 has the value of el. gender equal to zero. When mixing the measured wire 6 from the center of the OP 4 coefficient. the transmission associated with the first swing is reduced, and that associated with the next swing is increased. However, the total coefficient. transmissions of OP 4 will not change, T; that is, it does not depend on the position of the measured wire 6 in OP 4. Measurement accuracy is enhanced by the introduction of the microwave generator 2 and the directional coupler 3 and the selection of frequencies of the microwave generators 1, 2. 1 sludge. (L XX with with SP from 5

Description

The invention relates to a measurement technique, namely, radio wave control devices, and can be used in the manufacture of wire and products based on it.

The purpose of the invention is to improve the measurement accuracy.

The drawing shows the structural electrical circuit of the device for contactless measurement of the diameter of the wire.

The device for contactless measurement of the wire diameter contains the first 1 and second 2 microwave generators, the directional coupler 3, the open resonator 4, the indicator 5, the wire 6 under study.

ten

the transmission coefficient of the latter will be determined only by oscillations, since the mode of oscillations TEMTtc .. has in the center of the open resonator 4 a value of the electric field equal to zero. When the measured wire 6 is displaced from the center of the open resonator 4, the transmission coefficient of the latter, associated with oscillations TEMt. + 1, will increase, and associated with oscillation TEMmt f.- will decrease. However, the total transmission coefficient of the open resonator 4, fixed by the indicator 5, will not change. This follows from the fact that, for open resonators, the condition, and, as a rule, is satisfied. The device for contactless measurement is 15, the total electric field in either the wire diameter works in the center of the resonator 4

in a way.

Generators 1 and 2, working respectively-E U „

at frequencies f, and f, -f g-, excitation: u (-4

give in the open resonator 4 two “adjacent axial types of oscillations 1EM.scc and TEMmncfcM, where m, n are transverse, and q is the longitudinal vibration index. The type of oscillations TEMptpt has an electric field distribution in the center of an open resonator 4 along its axis, described by the expression

E E. soz-D-, where E, is the amplitude value of the electric field in the resonator 4; X is the current coordinate along the axis of the open resonator 4. The distribution of the electric field of the oscillation mode 1EN., 1 in the center of the open resonator 4 along its axis is described by the expression E

 EoSin- -. Indicator 5 captures

LI

the total transmission coefficient of the open resonator 4 associated with both modes of oscillation. When placing the measured wire b in the center of an open resonator 4

the transmission coefficient of the latter will be determined only by oscillations, since the mode of oscillations TEMTtc .. has in the center of the open resonator 4 a value of the electric field equal to zero. When the measured wire 6 is displaced from the center of the open resonator 4, the transmission coefficient of the latter, associated with oscillations TEMt. + 1, will increase, and associated with oscillation TEMmt f.- will decrease. However, the total transmission coefficient of the open resonator 4, fixed by the indicator 5, will not change. This follows from the fact that, for open resonators, the condition, and, as a rule, is satisfied. after 20

+ E, 2sin (. "E

i.e. does not depend on x. Therefore, the total transmission coefficient of the open resonator 4, fixed by the indicator 5, also does not depend on x and, therefore, on the position of the measured wire b in the resonator.

Claims (1)

Invention Formula A device for contactless measurement of the wire diameter, comprising a first microwave generator and an open resonator connected in series, made in the form of two coaxial reflectors, and an indicator, characterized in that, in order to improve the measurement accuracy, the second connected microwave generator and a directional coupler are introduced, The first microwave generator is connected to the second input of which, the frequency ratio of the first f, and the second fi of the microwave generator satisfies condition (f, -fi) 2j; . where C is the speed of light; L is the distance between coaxial reflectors.