SU1553844A1 - Belt-conveyer weigher - Google Patents

Abstract

The invention relates to a weighing equipment, in particular to devices for weighing continuously flowing material during its feeding. The aim of the invention is to improve the weighing accuracy of the belt scales and to simplify their maintenance due to periodic self-tuning at the moment of absence of the transported material on the conveyor belt. A second weight sensor 2, a load sensor 6, a code-time converter 9, two counters 12 and 14 registers and a pulse generator 19 are additionally introduced into the balance. Conveyor scales are distinguished from those known for ease of commissioning, blocking equipment manufacturing, which ensures a high degree of maintainability and minimal loss of time for troubleshooting. Due to the presence of a frequency signal, no additional equipment is required to convert the output signal and transfer it to a computer. 1 hp f-ly, 1 ill.

Description

BUT

Mi

{,

7777U / M //// t77777777777G

{,

(L

with

ate

with oo

4 Ј

3I

of the ported material. A second weight sensor 2, a load sensor 6, a code-time converter 9, two counters 12 and k registers and a pulse generator 19 are added to the scales. Conveyor scales differ from those known for ease of commissioning, block-wise manufacture of apparatus

The invention relates to a weighing equipment, namely, devices for weighing continuously flowing material during its feeding.

The purpose of the invention is to improve accuracy and simplify operation.

The drawing shows a schematic diagram of belt scales.

Conveyor scales contain the first weight sensor 1, the second weight sensor 2, the loading device 3 the transported material k on the conveyor belt 5, the load sensor 6, the speed sensor 7, three code converters 8-10 - time, setpoint generator 11 codes, first counter 12, register 13, second counter 14, trigger 15, generator

16 support frequency, the first element

17 matches, the third match element 18, the driver 19, the fourth match element 20, the second match element 21, the total counter 22, and the third counter 23.

Scales work as follows.

The first 1 and second 2 weight sensors are installed respectively after and before the loading device 3 under the upper (working) branch of the conveyor belt 5. The distance between them is UL. In these conveyor scales, electronic string sensors can be used as weight sensors, the output parameter of which is frequency.

The presence of the transported material C on the conveyor belt 5 between the loading device 3 and the first weight sensor 1 is determined by the loading sensor 6, which responds to the fact of material being fed to the conveyor belt 5. An optical sensor consisting of a light source and a photodetector can be used as such a sensor.

DT transport delay when moving the conveyor belt 5 with

3538W4

tours, providing a high degree of maintainability and minimal loss of time for troubleshooting. Due to the presence of a frequency signal, no additional equipment is required to convert the output signal and transfer it to a computer. 1 hp f-ly, 1 ill.

the speed v from the second weight sensor 2 to the first weight sensor 1 is equal to;

%

(and

In order to control the speed of the conveyor belt 5, it is possible to use TDS speed sensors, using the frequency fy of the emf produced by them as an information parameter.

The frequency signal of the speed sensor 7 is associated with its Kv conversion factor and the speed VK of the conveyor belt 5

 VK

(2)

If the coefficient Kv is made equal to r-, then the speed sensor 7 will be

issue each regular pulse after moving the conveyor belt 5 to a UL distance equal to the distance between the weight sensors 1 and 2. Thus, the speed sensor 7 sets the measurement cycle.

Under the action of weight at the output of sensors 1 and 2, we get frequency signals:

f K Kqo + q, ;; Кa K2D1Cho,

(h;

(four;

where K and K are the conversion factors of the first 1 and second 2 weight sensors; q 0 and q are the average linear weights of the conveyor belt 5 and the material 4 transported on it in the section of the conveyor belt 5 of length & L.

The next impulse of the speed sensor 7, for example, by its forward

5155

the front, to the first converter 8 code - time, the second converter i 9 code - time and the third converter 10 code - time the parallel binary code is recorded, respectively, from the outputs of the setpoint generator 11 code, the first counter 12 and register 13. After recording on the falling edge the pulse of the speed sensor 7 starts the first 8, second 9 and third 10 transducers; the code is time, the first 12 and second 14 counters reset to zero;

setting in state 1 of trigger 15.

The first converter 8 code - time forms a pulse, the duration

t no which is t4 -: - determined to be written

the binary number N0 into it and the reference frequency Ј0 of the reference frequency generator 16.

The first coincidence element 17, whose inputs are connected to the outputs of the second weight sensor 2 and the first converter 8 code - time, converts the frequency signal f, equivalent to the linear weight of the conveyor belt qo, into a serial pulse code number of pulses

(five)

N,

On the other hand, the number of pulses, depending on the weight of the section

fan belt 5 of length AL, its linear weight q0 and the weight value of one pulse uq must satisfy the condition

N N uq

(6)

From (h), (5) and (6) it can be seen that the binary number Ne set in the code setpoint 11 is determined by the expression

Nn

Jl f0

51 th 7Kg

(7)

A sequential number-pulse code N, the first counter 12 is converted into a parallel binary code N, which from the beginning of the next measurement cycle is recorded in the second converter 9, the code is time. The second transducer 9 code - time forms at its output the pulses the duration of which

mt fa

 rtf (8)

depends on the current running weight q0 of the conveyor belt 5 and the weight q4 of the material being transported 4. During operation, the duration T, depending on the conveyor load, can vary from the maximum value

T k,

when on conveyor belt 5

no transported material h (q, 0 ;, to the minimum T, - if

Oo „

--1 when the conveyor is loaded

Cho + Ch1max

to the maximum allowable running

load q ms ks.

The third element 18 Coincidence, the inputs of which are connected to the outputs of the second converter, the 9th code — time and the oscillator 16 of the reference frequency, outputs a serial N-pulse code N with the number of pulses

(9)

change from N.-- to N0 KiN

The number of pulses in this code, depending on the values of q0 and q, may

Kg.cjo

Cho + P1Mo.x Second counter 14 converts the serial number-pulse code N ,, into a parallel binary code.

Only binary code is written to register 13 from counter 1h.

N

N ° K;

five

0

five

Such a code is formed in the second counter 1 hour if the transported material 4 (q, 0) does not arrive at the conveyor belt 5 from the loading device 3 during the time Tg.

In this case, the first weight sensor I measures only the weight of a portion of the conveyor belt 5 without the material transported on it, which is measured by the weight sensor 2 in the previous cycle.

The third converter 10 code - time forms a pulse

t-t

- “to,

equal in duration to the impulse T formed by the second transform | Telem code - time.

shaper 19 on the falling edge of pulse T3 generates a short pulse, which, via the fourth element 20, coincidence, if there is an enable signal from trigger 15, recording is performed parallel

t /

N.N code - from the output of the second account

° K

WITH

And into the register 13. The recording enable signal from the output of the trigger 15 to the fourth element 20 matches only if, after the triggering pulse of the speed sensor 7 during the time T, the conveyor belt 5 is not received from the boot device 3 transported material 4. If, during time T, transported material 4 enters the conveyor belt 5 from the charging device 3, the trigger 15 returns to its initial state by a signal from the loading sensor 6

1 kg

and binary code entry - in

register 13 is not produced.

The second coincidence element 21, the inverse input of which is connected to the output of the second converter 9 code - time, the second direct input to the output of the third converter 10 code - time and the third direct input to the output of the first weight sensor 1, converts the frequency signal of the weight sensor 1 in a sequential number-pulse code.

Thus, the number of pulses in the number-pulse code is equal to .N3 (-T2; Ј4, or (after its conversion

.t

N, (S)

i la

From (10) it can be seen that the number of pulses NJ is equivalent only to the weight of the transported material in the section of the conveyor belt with a length Db.

The weight of the transported material on the section of the conveyor belt 5 is & L

,

In the final counter 22, the counting input of which is connected to the output of the second coincidence element 21, the result of the weighing during the operation of the conveyor is accumulated.

To obtain information about the load on the conveyor belt 5,

j

u 15 20

25

30 35

40

45

50

to use it, for example, for optimal loading of the conveyor, an additional third counter 23 is introduced, the counting input of which is connected to the output of the second coincidence element 21, and the Reset input - to the output of the speed sensor 7. Its first cascades have a division ratio

-. In subsequent cascades of windows & h

On the invoice, a binary number will be recorded corresponding to the current running load of the conveyor.

Claims (2)

1. Conveyor scales, containing the first weight sensor installed after the loading device, four elements of coincidence, trigger, speed sensor, the output of which is connected to the start inputs of the first and second converters code - time, setpoint code, the output of which is connected to the input of recording the parallel code of the first converter code - time, reference frequency generator, the output of which is connected to the input of the reference frequency of the first converter code - time, output of the first converter code - time is connected to one of the inputs of the first the coincidence element, the output of the second converter code — time is connected to the inverse input of the second coincidence element, and its output is connected to the counting input of the total counter, characterized in that, in order to improve accuracy and simplify operation, they have a second weight sensor installed before the boot device, the boot sensor, the third transducer code is time, two counters, a register and a pulse shaper, with the output of the speed sensor connected to the reset inputs of the first and second counters, one of the installation inputs one trigger and to the start input of the third converter code - time, the output of the first weight sensor is connected to the input frequency reference of the second converter code - time and through the second match element - to the count input of the total counter, the output of the second weight sensor is connected via the first match element to the count input the first counter, the output of the load sensor is connected to the second setup input of the trigger, the output of the reference frequency generator is connected via the third match element to the counting input of the second counter and to the input the third converter frequency code time — time; the output of the parallel code of the first counter is connected to the input of the parallel code write; the second time converter whose output is connected to the second input of the third match element; the output of the parallel code of the second counter is connected to the write input of the parallel register code, the output of the parallel register code is connected to the input of the record of the parallel code of the third pre 5 JQ 15 generator code — time, the output of which is connected to the third input of the second coincidence element and through the pulse shaper and the fourth coincidence element to the register record input, and the second input of the fourth coincidence element is connected to the trigger output. 2. The balance according to claim 1, characterized in that, in order to enable the measurement of the running load, a third count is entered - 4kfK, the counting input of which is connected to the output of the second coincidence element, and the reset input is connected to the output of the speed sensor.