SU468081A1 - Null organ - Google Patents

Description

power connected to the input of the delay circuit 11, the output of which is connected to the input of the pulse generator 12, supplying the strain gauge 13, to the high voltage delay 14 and 15, the last of which is connected to the coincidence circuit 16, trigger 17,. which together with the generator 18 pulses is connected to the logic element 19 AND

The device works as follows

The pulse from the output of the power supply source 1O (see FIG. 2, a) is fed to the inputs of the delay circuits 14 and 15 and, through the assembly circuits 8 and 9, to the control inputs of the keys 6 and 7 (see FIG. 2, e and g) which open for the duration of the pulse, connect the capacitors 2 and 3 to the output of the amplifier 1. The capacitors 2 and 3 through the keys 6 and 7 are charged before the voltage at the output of the amplifier 1 when the strain gauge 13 is de-energized. The delay circuit 11 (see Fig. 2, b) starts the generator of 12 pulses, which outputs a supply pulse to the strain gauge 13 (see, Fig. 2, e). In the measuring diagonal of the tensome bridge 13 a pulse appears, the polarity of which is determined by the sign of the imbalance of the tensome bridge, this pulse is amplified by amplifier 1.

At the end of the supply pulse, an impulse from the output of the delay circuit 14 (see Fig. 2, c) through the assembly circuit 8 goes to the control input of the key 6 (see, Fig. 2, which opens. When the key is opened). The voltage of 6 on capacitor 2 first increases (see Fig. 2, h) and then decreases as the voltage decreases at the output of the amplifier. Thus, capacitor 2 will be charged to a more viscous voltage than capacitor 3, which is charged before the voltage at the output of the amplifier when the tensomer is de-energized (see Fig. 2, g).

At the end of the power supply pulse of the strain gauge, the impulse from the output of the delay circuit 15 (see Fig. 2, d) goes through the assembly circuit 9 to the control input of the switch 7 (see Fig. 2, g). During this pulse, recharging of capacitors 2 and 3 occurs one on another, as a result of which the voltages of these capacitors become equal. Since for the case under consideration (see phi1, h) the voltage across the capacitor 3 decreases, then the output of the di (5) active circuit has a negative polarity pulse corresponding to the sign

unbalance of the tensome bridge; the false pulse of the positive field rnsty at the output of the differentiating chain is absent. At the time of arrival of the first pulse 5 (see Fig. 2, e and g) trigger 1 is set-i enters state 1 and closes element 19 I. At the same time, pulses from the output (of the generator 18 do not enter the control inputs of the keys 6 and 7, at the end of the pulse 10 from the output of the delay circuit 15, the trigger 17 is reset to O and the pulses from the output of the generator 18 through the element I begin to flow to the control inputs of the keys 6 and 7, which periodically open J5, the capacitors 2 and 3 charged in the previous tact, discharged to the voltage at the output of the amplifier with de-energized strain gauge 13 therefore, at the time of arrival of the first pulse (see Fig. 2, e and g)

20 capacitors 2 and 3 will have time to charge up to the voltage at the output of the amplifier, which reduces the recovery time of the null organ.

Subject invention

A null organ for a pulse-powered heaimetric measuring instrument containing a power source, an amplifier, a differentiating chain, a limiter, a coincidence circuit, and a trigger, characterized in that, in order to improve the measurement accuracy and reduce the recovery time of the null organ,

it is equipped with two electronic keys

two assembly circuits, three delay circuits, an AND logic unit, two pulse generators and two condensers; the output of the power supply is connected to one pulse generator supplying the strain gauge of the device through two other circuits, delays and two assembly circuits - to the manager

the inputs of the keys connected between the amplifier and the differentiating chain, at the input of which one of the capacitors is connected, connected to another capacitor connected between the keys, through the same two circuits,

delays — to the external circuit and to the trigger, the second input of which, together with the inputs of both assembly circuits, is connected to the output of the power source, and the outputs of the trigger and other pulse generator through logic

The cI element is connected to both of the assembly schemes.

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