SU1649246A1 - Displacement meter - Google Patents

Abstract

The invention relates to the measurement technique and allows to increase the sensitivity of the displacement meter of the auto-oscillator type, which contains the auto-oscillator 1, made in the form of a symmetric KS-multivibrator with two transistors 2 and 3. Capacitors 5, перекрест cross links between the bases and collectors of these transistors differential displacement transducer Parallel to the capacitors 5, 6, two quartz resonators 7 and 8 are connected, which have a shunting effect on the purpose of recharging 5 and capacitors 6, which changes the pulse duration of the voltage at the collectors of transistors ,, By this curvature increase is achieved conversion characteristics and increase sensitivity izmerite- l displacements., 1 yl of 3

Description

The invention relates to measuring equipment and can be used to control movements "

The aim of the invention is to increase the sensitivity of displacement meters of the oscillator type with a capacitive sensor by changing the frequency properties of the feedback circuits of the oscillator ,, 19

The drawing shows a circuit diagram of a displacement meter

The displacement meter contains a self-oscillator 1, made according to the diagram of a symmetric multivibrator on two transistors 2 and 3, and a capacitive differential sensor 4 connected to them, capacitors 5 and 6 of which are used as cross-links between collectors and transistor bases. Parallel capacitors 5 and 6 are connected two quartz resonators 7 and

8, and a measuring device is connected to the collectors of transistors 2 and 25 3

9, designed to measure the average value of voltage pulses between the collectors of transistors and 3. 30

The displacement meter operates as follows

When moving the control object, the capacitances of the codensators 5 and 6 of the differential sensor 4 “change in opposite directions,” this leads to a change in the relative pulse durations on the collectors of transistors 2 and 3, generated by a multivibrate oscillator 1 ”, the pulse duration on the collector of one transistor (for example, transistor '2) increases, and on the collector of another transistor 3 - falls _o The resistance of the quartz resonator 7 decreases sharply with increasing harmonic number. This is equivalent to shunting the capacitor 5, which leads to an additional decrease in the pulse duration on the collector of transistor 3, and hence the average voltage value on it ”

The effect of quartz resonator 8 on the pulse duration on the collector of transistor 2 will be the opposite

Due to the decrease in the content of higher harmonics, the shunt effect of the quartz resonator 8 decreases, which leads to an additional increase in the pulse duration at the collector of transistor 2 and therefore to an increase in the average voltage on it. ”Due to the additional influence of quartz resonators, an increase in the slope of the conversion characteristic of the meter and its sensitivity is achieved. ,

Claims (1)

Claim Displacement meter, containing a high-frequency oscillator, · made according to the symmetric multivibrator circuit on two transistors and two elements forming cross-links between their collectors and bases, and a capacitive displacement sensor, which is equipped with two quartz resonators, connected in parallel to the elements of cross-links, and the capacitive displacement transducer is made differential in the form of two variable capacitors, which are used in as cross-linking elements