SU712808A1 - Time interval measuring device - Google Patents

Description

The invention relates to measuring technique and can be, in particular, used in the development of time interval meters.

Known devices for measuring time intervals with a digital readout of the measurement result, containing an input driver that generates pulses at the moments of the beginning and end of the measured interval, the main and auxiliary pulse generators, an electronic key circuit, the main and auxiliary pulse counters, two digital readout devices. In these devices, the measurement result is determined by the totality of the readings of the primary and secondary counters [1].

A device for measuring time intervals containing two generators, the pulse repetition rate of which is determined from the condition of the vernier conversion, the inputs of which are connected to the corresponding outputs of the input driver, the main output through the key, and the auxiliary directly connected to the inputs of the main and auxiliary counters, respectively, whose outputs are in turn, they are connected to two display units, a trigger, and the second key input is combined with the input of the auxiliary generator [2].

Meters of this type are characterized by measurement errors associated with the ambiguity of the “coincidence zone”.

The aim of the invention is to increase 5 measurement accuracy.

For this, two additional electronic keys are added to the device, a comparison circuit and a counter, the outputs of which are connected to the inputs of the comparison circuit, on the other 10 inputs of which an auxiliary counter is switched on. In this case, the output of the main pulse generator is switched on to the first combined inputs of the additional keys, the output of the first of which is connected to the 15 input of the additional counter, the output of the second to the trigger input, and the second input of the second additional key to the input of the auxiliary generator. The output of the comparison circuit is connected to the inputs of the installation 20 of the initial state of the trigger and generators.

The drawing shows a diagram of the device.

The device consists of an input driver 1 that generates 25 pulsed signals at the beginning and end of the measured time interval; main 2 and auxiliary 3 pulse generators operating in standby mode; keys 4, 5 and 6; trigger 7 with separate 39 inputs; main 8, auxiliary 9 and additional 10 counters of impulse 712808 owls; Scheme II code comparison; digital readout devices 12 and 13.

The device operates as follows.

Before starting the measurement, the circuit is in the initial state: controlled generators 2 and 3 are turned off, key 4 is open, and keys 5 and 6 are closed, counters 8 and 10 are in the zero state, and one is written in counter 9.

At time point / _]; the signal of the shaper 1, corresponding to the beginning of the measured interval T _x , starts the main generator 2 with a pulse repetition rate / DOS. The pulses of the generator 2 pass through the key 4 and are counted by the main counter 8.

At time t _{2, the} shaper 4 closes with the signal of the shaper 1 corresponding to the end of the interval T _x . The counting of pulses by the main counter 8 is stopped and the counting result is recorded on the digital reading device 12. The key 5 is opened with the same signal and the auxiliary 3 pulse generator is started with a frequency Chain · Pulses of generator 3 are counted by auxiliary counter 9. ' At the same time, through the public key 5, the trigger 7 switches to state “1” with the pulse of the main generator, which opens the key 6. The pulses of the main generator pass through the key 6 and are counted by an additional counter 10.

The number of pulses recorded by the auxiliary 9 and additional 10 counters are constantly compared by the code comparison circuit 11. At the moment of equivalence of the codes, the circuit 11 generates a signal that sets the trigger 7 and the generators 2 and 3 to their initial state. In this case, the pulse count by the auxiliary and additional counters is terminated and the counting result is recorded on the digital reading device 13. This completes the measurement cycle.

If between the frequencies Ts _{C1 [} And the Chain holds the ratio Tsspom / Tsspom focu = - 10 ^m , then the number of LCs, made up of the readings of the main counter in the direct code and the auxiliary counter, corresponds to the measured time interval T _x . The digital measurement result corresponds to a time interval determined by the sum of the intervals obtained in the first and second measures

T _x - (AC _0CH + L / recall '”) • T'v” where T _o is the period of oscillations of the main pulse generator;

m is the number of additionally estimated digits of the measurement result.

Claims (1)

Claim A device for measuring time intervals containing two generators, the pulse repetition frequency of which is determined from the condition of the vernier transformation, the inputs of which are connected to the corresponding outputs of the input driver, the output of the main through the key, and the auxiliary directly connected to the inputs of the main and auxiliary counters, respectively, whose outputs the queue is connected with two indication blocks, a trigger, the second key input being combined with the auxiliary generator input, which differs in that, in order to improve the measurement accuracy, two additional electronic keys were introduced into it, a comparison circuit and a counter, the outputs of which are connected to the inputs of the comparison circuit, on the other inputs of which an auxiliary counter is included, the output of the main pulse generator being connected to the first combined inputs of additional keys, the output of the first of which is connected to the input of the additional counter, the output of the second to the trigger input, and the second input of the second additional key to the input of the auxiliary generator, with the output of the circuits Comparison s are connected to the inputs for setting the initial state of the trigger and generators.