SU1758630A1 - Digital meter of ratio of two time periods - Google Patents

Abstract

The invention relates to a measurement technique and can be used in the construction of time-ratio meter. The meter contains a counting pulse generator 14, an integrator 9, four electronic switches 5-8, a reference voltage source 4, an inverting amplifier 13, a comparator 10, sampling-storage units 11 and 12, a control block 2, a time selector 15, a pulse counter 16, shapers 1 and 3 pulses. 1 il.

Description

The invention relates to electrical radio measuring equipment and coins to be used in constructing time interval ratio meters.

A time interval meter is known, containing a DC generator, a charging switch, a DC amplifier, a storage capacitor, a discharge switch, a discharge resistor, the ungrounded pole of the DC generator connected to the middle contact of the charging switch, the first the contact of which is connected to the input of the DC amplifier, one plate of the storage capacitor and one output of the discharge resistor, the second plate of the storage capacitor is connected to the output of the amplifier constant th current contacts and one of the p-stand time key, a second contact which is connected to the other terminal of discharge resistor, and the control inputs

The charge and bit keys are the inputs of the device,

The disadvantage of the meter is insufficient accuracy, since the output voltage contains pulsations caused by the non-simultaneous action of the charging and discharging circuits.

The closest to the claimed relates to the meter ratio of two time intervals, the contents of the DC generator, capacitor, charge, bit and auxiliary switches, a single-oscillator, an integrator and a voltage-current converter.

The method of measuring the ratio of time

Tt

intervals - in the device proto- 12

The type is that the charge of the capacitor during the time T, | (i + l) with the reference current 1O is fully compensated by its discharge during the time) current created by VI

sl co

hmmm voltage transducer - choke. This meter represents an oboe pulse tracking automatic control system, the input and output of which is connected to a capacitor and which includes an additional switch, an integrator, and a voltage converter — a current.

To the disadvantage of such a meter should be attributed low speed, due to the fact that the time of the transition process, which begins at the time of the signal T $

and ends in time 1 (1 + 1), 15 of the control unit 2, and the output from the input

The electronic key 6, the first, second, third, sixth outputs of the control unit 2 are connected respectively to the control inputs of the electronic switches 5-8, the fourth and fifth outputs of the control unit 2 are connected respectively to the control inputs of the sample-storage blocks 11 and 12 . The output of the comparator 10 is connected to the fourth input of the control unit 2. The counting pulse generator 14 is connected to the input of the time selector 15, whose control input is connected to the seventh output

5 control unit 2, and output - with input

turns out to be too large, which is especially noticeable in the low frequency range.

The purpose of the invention is to increase the speed of the meter in the low frequency range.

The goal is achieved by the fact that in the proposed device, pulse preformers 1 and 3 produce impulses whose durations are equal, respectively, to T and T.

The device has four workers

the formation of time intervals corresponding to the values of T and Tg in a cycle of 25 cycles. During the first cycle, which is a different voltage followed by the next one, with the arrival of a pulse, the ratio of these voltages in the division unit, which is a double integration CPU

The drawing shows a structural diagram of the meter.

The device contains shapers

from the output of the pulse shaping device 1 to the first input of the control unit 2, the last output of output 1 produces a 30 pulse opening key 5. The input of the integrator 9 receives a constant voltage U0 from source 4. Backs1 and 3 pulses, source 14 of the reference voltage, electronic switches 5-8, integrator 9, inverting amplifier 13, comparator 10 blocks 11 and 12 sampling-storage, control unit 2, generator 14 of counting pulses, time selector 15, counter 16.

The first input of the meter through the serially connected pulse shaper 1 is connected to the first input of the control unit 2, the second input of the device through the serially connected forming device., 3 is connected to the second input of the control unit 2. The source 4 of the reference voltage is connected to the input of the electronic key 5, the output of which is connected

from the output of the pulse generator 1 to the first input of the control unit 2, the last pulse 30 outputted at the output 1 opens the key 5. The input voltage of the source 4 from the source 4 is supplied to the input of the integrator 9, and the pulse leading edge coming from the pulse generator 1, The 2 2 $ control unit closes the electronic key 5 O The integrator 9 charges up to the voltage

U

int

4- -Ј / Vdt f U0 T1

(one)

fr

40 °

where UHHT is the voltage of the integrator

after the first .t;

- constant of integrator time 9;

- the period of the investigated signal at the input of the driver 1 pulses, At the end of the first cycle unit 2

T

The control generates a pulse, with a point combining the outputs of the electronic 5Q permitting the recording of the voltage of the vital keys 6–8 and the input of the integrator 9 in the unit, 12 sampling and storage. According to the windows, the output of the integrator 9 combines the inputs of: electronic key 8, comparator 10, blocks 11 and 12 of the sample storage. The output of the sampling-storage device 11 is connected to the input of the electronic switch 7. The output of the sampling-storage unit 12 is connected to the input of the inverting amplifier 13, the output of which is connected

In the recording, the control unit 2 generates a pulse that closes the key 8, thereby resetting the integrator

During the second measure, which

begins with the arrival of a pulse from the output of the pulse generator 3 to the second input of control unit 2, by feeding the counter 16, the output of which is connected to the third input of control unit 2

The device works as follows.

Pulse formers 1 and 3 produce impulses whose durations are equal to T and T, respectively.

The device has four workers

tact During the first cycle, which begins with the arrival of an impulse

tact During the first cycle, which begins with the arrival of an impulse

from the output of the pulse former 1 to the first input of the control unit 2, the last output 1 of the pulse produces a key opening 5. The input of the integrator 9 receives a constant voltage U0 from the source 4. A pulse leading edge coming from the pulse former 1, the unit 2 controls closes the electronic key 5 O The integrator 9 is charged before the voltage

,

U

int

4- -Ј / Vdt f U0 T1

(one)

fr

0 °

where UHHT is the voltage of the integrator

after the first .t;

- constant of integrator time 9;

- the period of the investigated signal at the input of the driver 1 pulses, At the end of the first cycle unit 2

T

The control generates a pulse that permits the recording of voltage to the unit, 12 sampling-storage. By windows

In the recording process, the control unit 2 generates a pulse that closes the key 8, thereby resetting the integrator

During the second measure, which

begins with the arrival of a pulse from the output of the pulse generator 3 to the second input of the control unit 2, the last n output 1 generates a pulse opening the key 5 A constant voltage is applied from the source 4 to the input of the integrator 9. The pulse leading edge coming from the pulse former 3 , the control unit 2 closes the electronic key 5. The integrator 9 is charged before the voltage

U

int2 where u

- -i%

-C- J with

dt - Јv

L2

(2)

Intg T2

integrator voltage after the second cycle; the period of the signal under study at the input of the generator 3 pulses of

At the end of the second cycle, the control unit 2 generates a pulse permitting the recording of the supply voltage in the sampling-storage unit 11. At the end of the recording, the control unit 2 generates a pulse that closes the electronic key 8, thereby producing a reset of the integrator 9.

At the beginning of the third cycle, the control unit 2 opens the electronic, the key 6 and the input of the tegrator 9 receives voltage from the inverting amplifier 13. At the same time, the time selector 15 opens and the input of the counter 16 is allowed to pass the counting pulses from the generator 14.

At the moment when the counter 15 overflows, the third clock cycle is completed and the integrator 9 is charged before the voltage and INT.

U

Te

INTE

-Lh

Int,

Kdt and „

(3

 the integrator output voltage after the third cycle ;;

 the transfer coefficient of the inverting amplifier 13;

- the duration of the third cycle.

Sign - under the sign of the integral k1 of equality 3 shows that the amplifier 13 inverts the signal.

With the beginning of the fourth integration cycle, the electronic key 7 is closed and the input of the integrator 9 is energized from the output of the sampling-storage unit 11

nothing Integrator capacitor bit - 55 second pulse driver connect

It is at the moment when the output

and Thurs }

the tendency will become equal O (II

+ iINT (0), at the output of the comparator 10

an impulse is generated

7586306

on the fourth entrance (sticky m. rach chchy. The last 7 seconds on the outlet is a pulse that prohibits the passage of counting pulses from the generator 14 via the transmitter 15 to the input of the counter 16, thus:

U

Int

 -U

AI

 -

U

5 J °,

 dt

ten

f

(four)

and

Knowing that the time intervals tg Cd are filled with counting pulses.

generator 14 with frequency f., then:

Ne / fo,

Ny / f0,

(five)

where N0, Nj (- the number of pulses, respectively, in the third and

Resha (4)

 -TO

fourth cycle integration with

relatively icht

t L

-4: 5lT

(6)

And "T2 With regard to (1), (2), (5):

T1 2 Output code NJ, will be proportional

n „-K-NO- (7)

35

magnitude ™.

Lt

Claims (1)

Invention Formula 45 A digital meter for the ratio of two time intervals, containing a 40 counting pulse generator, an integrator, an electronic key, is due to the fact that, in order to increase the meter speed in the low frequency range, two pulse shapers were introduced into it, three electronic keys, inverting amplifier, comparator, two sampling-storage units, control unit, time selector, pulse counter, the first input of the device through the first pulse shaper connected to the first input of the block admin50 laziness, the second input of the device through not connected to the second input of the control unit; the voltage source is connected to the first input of the first electronic key, the output of which is connected with the outputs of the second and third electric switches, respectively, with the supreme input of the fourth electronic key and with the input of the integrator, the output j of which is combined with the output of the fourth electronic key, with the input of the comparator, with the first inputs of the sampling-storage units, respectively, the output The first sampling-storage unit is connected to the first input of the third electronic key, the output of the second sampling-storage unit is connected to the input of an inverting amplifier, the output of which is connected to the first 15 input of the first electronic key, the first the second, third, sixth outputs of the control unit are connected to the second inputs of the first, second, third keys, respectively, the fourth and fifth outputs of the control unit are connected, respectively, to the second inputs of the first and second sample-storage blocks; the comparator output is connected to the fourth input of the unit control, the counting pulse generator is connected to the first input of the time selector, the control input of which is connected to the seventh input of the control unit, and the output of the time selector is connected to the input of the pulse counter, turn is connected to a third vho- (Tzom control unit.