SU1672229A1 - Belt-conveyer weigher - Google Patents

Abstract

This invention relates to a mass measuring technique. The purpose of the invention is to increase the accuracy of weighing. The signal from the mass sensor 2 is fed to the first input of the tare mass calculator 5, the second input of which receives a signal from the gate generator 4. If there is a gate and a loaded conveyor belt passes through the mass sensor 2 to the input of frequency divider 21 through elements 14, 15, element OR 19 receives high frequency signals and frequency divider 21 overflows, the overflow pulse of which gives resolution to element 16, the signal from which through frequency divider 6 enters the total counter 9 for calculating the mass of the load. When the unloaded conveyor belt passes through the mass sensor 2, the frequency divider does not overflow and the signal from the output of the mass sensor 2 after the gate disappears at the output of block 4 through element 18, output 13 of the tare mass calculator 8, frequency divider 7 is fed to the subtracting input of the final counter 9 for calculating the mass of the unloaded conveyor belt. 1 il.

Description

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The invention relates to a mass measuring technique and can be used dp weighting of the rock mass during its transportation by belt conveyors.

The aim of the invention is to improve the weighing accuracy.

The drawing shows a diagram of belt scales.

Conveyor scales contain a conveyor belt 1, a mass sensor 2 that converts the load into a frequency, a speed sensor 3 that converts the speed of the conveyor belt into a frequency, a gate generator 4, a tare mass subtraction unit 5, frequency dividers 6 and 7, a division factor setter 8 and a reversible total counter 9. The tare mass subtraction unit includes, respectively, the first 10 and second 11 inputs and the first 12 and second 13 outputs, five AND AND - 18 circuits, two elements OR 19 and 20, the first frequency divider 21 and the trigger 22. Gates 4 including 1 trigger 23, d frequency divisor 24, the generator 25 and the AND gate 26.

The output of the weight sensor 2 is connected to the first input 10 of the unit 5 for subtracting the tare mass; to the second input 11 of the same unit, the output of the speed sensor 3 is connected via the gate generator 4. The first inputs of the second 6 and third 7 frequency dividers, respectively, are connected to the first 12 and second 13 outputs of the unit 5 for tare mass reading, and the output of the setting unit 8 of the division factor is connected to the second inputs of the second and third frequency dividers, the summing and subtracting inputs of the total counter 9 are connected respectively to the outputs of the second 6 and third 7 frequency dividers.

In block 5, the subtraction of the tare mass to the first input 10 is connected to the first input element And 14, the first (inverse) input element And 17, as well as the first input element I / I 18. To the second input 11 of block 5 connected the second input element And 14, the second (inverse) inputs of the elements And 17 and 18, as well as the input R of the trigger 22. To the output of the element 14 are connected the first inputs of the elements 15 and 16. The output of the element 16 connects to the first output 12 of the unit 5 subtracting the tare mass and the second output 13 the same block 5 is connected to the output of the element And 18 and with the first input of the element OR 19, the second input of which is connected nen yield AND gate 15.

The output of the OR 19 element is connected to the counting input C of the frequency divider 21, the input R (of the zero setting) is connected to the 5 input of the trigger 22 and the output of the AND 17 element.

The direct output of the trigger 22 is connected to the first input of the element OR 20, the output of which is connected to the third (inverse) input AND 18. The second input of the element OR 20

connected to the output of the splitter 21 frequency, as well as with the second inputs of the elements And 15 and 16 and with the third input of the element And 17.

Conveyor scales work as follows.

0 A speed sensor 3 converts the speed of movement of the conveyor belt 1 into a frequency proportional to the speed of the belt. The signal from the speed sensor 3 is supplied to the 4 gate driver, which forms

5 is a signal (p. Ob) of a predetermined duration, which is fed to the unit 5 for subtracting the tare mass. In this case, each gate is formed after passing through the speed sensor 3 (i.e., through the mass sensor 2) is strictly determined by the 0 / Gene length of the conveyor belt, therefore, the gate frequency is proportional to the speed of the conveyor belt.

The mass sensor 2 converts the force of the pressure of the conveyor belt to the sensor into a frequency directly proportional to the force acting on it.

Signals from mass sensor 2 pass through element 14 only if

0 input element AND 14 signal from the driver 4 gates. Further, these signals from the element AND 14 through the elements AND 15 and OR 19 arrive at the counting input of the frequency divider 21.

5If during the time of the strobe (signal

from the driver 4 gates) the load on the mass sensor 2 will be such that it can provide the frequency necessary to fill the frequency divider 21, then at the rear

0 front-input signal to input C frequency divider 21 goes into a state The frequency divider is full and a signal is output at the output that, arriving at AND 15, will prevent the signal from passing

5 and 14 to the frequency divider 21, at the same time, arriving at the element 16. And will allow the same signal to pass from the element 14 through the element 16 on the first output 12 of the unit 5 subtracting the tare mass and then on

0 divider is 6 frequencies, i.e. will take into account the weight of the goods located on the weighed area of the tape.

With the disappearance of the gate (from the output of the former 4 gates) at the moment when

5 mass sensor 2 does not receive an output signal, element 17 will give a signal to the R input of the reset of the frequency divider 21 and thereby prepare the unit 5 for subtracting the tare mass for operation when a new signal appears at the output of the 4 gate generator,

with its leading edge, it triggers trigger 22 to zero.

If a lightweight (without load) section of the conveyor belt 1 passes through the mass sensor 2, i.e. the conveyor belt, the running weight of which is less than the average linear weight of the entire conveyor belt 1, then the output of the mass sensor 2 shows a low frequency signal and in this case, during the presence of the signal at the output of the 4 strobes, the frequency divider 21 does not fill and its output does not show the signal of filling the frequency divider. After the disappearance of the signal (strobe) from the output of the imager 4, the coffins of the signal from the mass sensor 2 go through the element 18 and the element OR 19 to the input of the frequency divider 21, and simultaneously arrive at the second output 13 of the unit 5 to read the tare and then to the separator 7 frequencies, i.e. The difference between the weighed area of the conveyor belt and the average weight of the same section of the conveyor lemta is taken into account.

When filling the frequency divider 21 at the output front of the signal from the mass sensor 2, a signal appears which, passing through the OR element 20, prohibits the passage of signals from the mass sensor 2 through the AND 18 element and at the same time prepares the AND 17 element for forming in the first pause between the pulses of the signal from the mass sensor 2 to the S input of the trigger 22 and the last one is switched to the Unit state, and at its output there appears a signal that the passage through the OR element 20. also prevents the passage of signals from the mass sensor 2 through him

When the next signal appears at the output of the 4th gate generator, trigger 22 by the leading edge of this signal is transferred to the Zero state and the device starts operating in a new cycle.

Claims (1)

Claims of the invention: Conveyor scales containing a mass sensor, the output of which is connected to the first input of the subtraction mass of the container, the second the input of which is connected to the speed sensor through the gate driver, the dividing ratio setting unit, the total counter, and the tare mass subtraction unit contains a trigger, the first frequency divider and three AND elements, the first and second tare mass subtractor inputs are respectively connected to the first second inputs of the first element And, the output of which is connected to the first inputs of the second and third elements And the output of the third element AND is connected to the summing output of the block mass subtraction unit, characterized in that. In order to improve accuracy, they introduced the second and third frequency dividers, the first inputs of which are respectively connected to the summing and subtracting inputs of the flea, the subtraction of the tare mass, the inputs to the setting factor of the division factor, the outputs to the totaling and subtracting inputs of the total and two units OR, the fourth and fifth elements AND, the first and second inverse inputs of the fourth element AND, respectively, are connected to the first and second inputs of the first element And, the output four of the solid element AND is connected to the S-input of the trigger, the R-input of the first frequency divider, the counting input of which through the first OR element is connected to the output of the second AND element, the second input of which is connected to the output of the first frequency divider, the second input of the second OR element, the second input of the third the AND element, the third input of the fourth AND element, the first input of the second OR element is connected to the trigger output, the R input of which is connected to the second inverse inputs of the fourth and fifth AND elements, the output of the second OR element is connected to the third inv A digital input of the first element is And, the first input of which is connected to the inverse of the first input of the fourth element And, the second input of the first element OR is connected to the output of the fifth element And and is the subtracting output of the unit of mass subtraction tdra.