SU1527512A1 - Weight measuring device - Google Patents

Abstract

The invention relates to weighing technology and can be used in devices with the compensation of tare load, in particular in automatic conveyor scales. The purpose of the invention is to increase the reliability of the device in operation. The weighing device contains serially connected load sensor 1, frequency converter 2, control unit 7, output counter 5, display unit 6. New in the device is that two reversible counters 3 and 4 of the initial load are introduced into it, and the control unit 7 consists of two triggers 8 and 9, five AND elements, four OR elements, inverter 19, an expander and a pulse shaper. 1 il.

Description

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The invention relates to weighing technology and can be used in devices with compensation of tare load, in particular in automatic conveyor scales,

The aim of the invention is to improve the reliability of the device.

The drawing shows the functional diagram of the device.

The weighing device contains a load sensor 1, a frequency converter 2, reversible counters 3 and 4 of the initial load, an output counter 5, an indication unit 6, a control unit 7 consisting of two triggers 8 and 9, and 10 10 elements. , four elements OR 15–18, inverter 19, pulse expander 20, and driver 21 pulses.

The device works as follows.

The measured load causes on the code of the load cell sensor 1 a signal which is converted in the frequency converter 2 into a sequence of pulses, the number of which corresponds to the measured load.

If there is no weighing object on the scales, the Tara impulse received at the first control input of the control unit 7 controls and resets the reversible counters 3 and 4 of the initial load and sets the trigger 8 to the state 1 through the element OR 17, zero output which blocks the element And 14, and a single unlocks the element And 13. cash Tara through the element OR 16 mouth

Puts the trigger 9, the blocking element AND 10 and the unlocking element AND 12 into the state O, and also starts the pulse expander 20 to form the time interval T, s, during which the pulses are counted. Pulses from the output of frequency converter 2 through the elements AND 11 and OR 18 arrive at the direct input of the reversing counter 3, recording the initial load (tare) R.

If an item is weighed on the scales, then the Gross signal received at the second control input of the control unit 7 blocks the passage of the measured load pulses through the And 11 element through the inverter 19 and allows them to pass through

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element AND 12. At the same time, the gross signal through the pulse shaper 21 and the element OR 16 resets the trigger 9 and starts the pulse expander 20 to form T ,. The pulses, the number of which corresponds to the gross weight (Pf), from the output of frequency converter 2 through the elements AND 12 and OR 13 arrive at the reverse input of counter 3 and the direct input of counter 4. As soon as counter 3 has zeroed, and in counter 4 will overwrite the value of the initial load P, the signal from the output of the counter 3 resets the trigger 9, and through the OR element 15 sets the state 1 to the trigger 9. At the same time, the AND 12 element is blocked and the subsequent pulses pass through the AND 10 element to the output counter 5,

Thus, the output counter 5 receives the number of pulses P Pg-P corresponding to the value of the payload, which is indicated by the display unit 6.

During the subsequent weighing cycle of the Gross control signal, the pulses from converter 2 through element 12 and unlocked by trigger 8 element 18 of the pin 14 are fed to the reversing input of counter 4 and through element OR 18 to the forward input of counter 3, restoring the value of P (,. The output signal of the counter 4, generated when it is reset, sets state 1 through the elements OR 17 and 15 to the triggers 8 and 9. The first switches the elements 13 and 14 again, the second switches the elements 10 and 12, providing a pulse load P in the output count uk 5.

So at each weighing there is a census of the value P originally recorded in the counter 3, from one reversible counter to another. The initial recording of Pp is stored in reversible counters until the arrival of a Tara pulse, which is corrected in counter 3 of the magnitude of the initial load. The moment of formation of the Tara signal is determined by the nature of the operation of the weighing device.

Claims (1)

Invention Formula The weighing device containing a serially connected load sensor, frequency Converter, control unit, output counter and display unit, characterized in that, in order to increase reliability, two reversible initial load meters are inserted into it, and the control unit is made in the form of two triggers, five AND elements, four OR elements, an inverter , the expander and pulse shaper, and the output of the frequency converter is connected to the first inputs of the first, second and third elements And the output of the first element And connected to the input of the output counter, the second element And to the first input of the fourth the OR element, the third AND element - with the first inputs of the fourth and fifth AND elements, the second inputs of which are connected respectively to the unit and zero outputs of the first trigger; the output of the fourth AND element is connected to the reversing input of the first and direct input of the second initial load counter, output n This element AND is connected to the reversing input of the second initial load counter and the second input of the fourth OR element, the output of which is connected to the direct ten 27512 the input of the first initial load counter, the output of the first initial load counter is connected to the first input of the first OR element and the R-BXO- house of the first trigger, the output of the second counter is connected to the second input of the first OR element and the first input of the third OR element, the output of which is connected to S- the input of the first trigger, the output of the first element OR is connected to the S-input of the second trigger, the unit code of which is connected to the second input of the first element AND, and zero to the second input of the third element AND, the first input of the second element OR connect with the second input of the third element OR and the R-inputs of the initial load meters, the output of the second element OR is connected to the R-input of the second trigger, as well as to the input of the pulse expander, the output of which is connected to the second input of the second and third inputs of the third 25 AND , the fourth input of the third element And is connected via an inverter with the third input of the second element AND, as well as with the input of the pulse shaper, the output of which is connected to the second input of the second element OR. 15 20