SU767550A1 - Conveyer weigher - Google Patents

Description

one

This invention relates to a weighing appliance.

Belt scales are known in which an analog signal proportional to mass is converted into a sequence of pulses entering the counter, where 1 is summed.

The closest in technical essence to the invention are belt scales containing a load-receiving platform, a mass sensor and an analog signal converter, proportional to the mass of the material, into a sequence of pulses consisting of switching on and off 15 devices connected to trigger trigger inputs of a source pulses and an element, the inputs of which are connected to the outputs of the trigger and the source of pulses, and the output with a pulse counter-20 pulses. 2. The disadvantage of these conveyor scales is that they accumulate in the counter any deviation of the output signal, exceeding the maximum by 25 times half the price of the counting impulse, when the conveyor is idling. This deviation may be caused by the drift of the mass sensor zero or by the heterogeneity of the conveyor belt, or 30

2

mechanical vibrations of the belt, or other reasons. Increasing the resolution when reading an analog signal leads to a decrease in the zero zone, which is half the price of the impulse, i.e., an even greater likelihood of a false signal accumulation when the conveyor is working and the scale is idle.

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

This goal is achieved by the fact that conveyor scales are equipped with a second trigger and an element AND, a decoder, the inputs of which are connected to the bits of the pulse counter, the zero input of the second trigger connected to the output of the decoder. and one - with the output of the switching device, while one input of the second element I is connected to the output of the second trigger, the second input - to the output of the switching device, and the output - to the reset bus of the pulse counter.

FIG. 1 shows a diagram of a conveyor scale; in fig. 2 - output ha.

 The platform 1 is supported by one or more mass sensors 2. The signals of the last come

Into the intermediate conversion unit 3, which forms the output signal of mass sensors in the form of angle f of shaft 4 rotation. Angle H is proportional to the mass of material in the weighed part of the conveyor belt 5. On shaft 4, the command head b is reinforced (inductive, magnetic modulation, capacitive, optical , jet-pneumatic, etc.). The roller 7 in contact with the conveyor belt 5 is connected to the shaft 8, on which the command coding element is fixed, made, for example, in the form of a disk with gear 9, interacting with the command heads b and 10. The tooth 9 and the head b form the switching device. The stationary command head 10 With respect to the position of which the angle H of rotation of the shaft 4 is measured, forms a switching device with the prong 9.

A coding disk 11 with a plurality of coding elements uniformly circumferentially positioned, for example, teeth, intercommunicating with a fixed reading head 12, is also fixed on the shaft 8.

The coding disk 11, in combination with the read head 12, forms a source of pulses. .

The source of pulses (the output of the read head 12) through the element And 13 is connected to the counter 14 pulses. The second input element And 13 is connected to the trigger output 15 ..

The unit input of the trigger 15 is connected to the output of the switching device (command head b), and the zero input of the trigger 15 is connected to the output of the switching device {command head 10). /::

The outputs of the initial bits of the counter 14 are connected to the inputs — configurable; the decoder 16, the output of which is connected to the zero input of the second trigger 17. The single switch of the trigger 17 is connected to the output of the trigger, its device (command head b), and the output of the trigger 17 - with the input of the element 18. The input of the element 18 of the syediyon with the output of the switching off device (command head 10), and the output of the element 18 of the 18 with the reset bar for zero counter bits 14 pulses that are included in the number specified by the decoder 1b, the counter 14 connected to the meter: 19 li iey at which 015uScho stvL a yereios as peropol Neny counter 14.

Circular scales work as follows.

. The roller 7T1riv-oy b so the rotation of the conveyor belt 5. From the roller 7, the rotation is transmitted to the shaft 8 with the coding disk 11 and the command element with a tooth 9.

- ШБсГ1Щ ё | IM 1 ON YOURSELF the conveyor belt section, converted into a proportional

angle t of rotation of shaft 4 with a command head mounted on it b. The command tooth 9 interacts with the command head 6. In this case, a trigger signal is applied that goes to the single inputs of the flip-flops 15 and 17. The single output signal of the flip-flop 15 is fed to one input of the element I 13, and the second input goes pulses from the source of the pulses encoding disk 11 read head 12). These pulses pass through the element AND 13 into the counters 14 and 19. The pulses will pass through the element 13 and as long as the command tooth 9 does not intersect the command head 10. The arising switching signal will arrive at the zero input of the trigger 15. As a result, the output of the trigger 15 in Wits zero SYA, the th element And 13 closes. The number of pulses received in the strips 14 and 19 will be proportional to the angle of rotation I of the shaft 4 with the command head b. If the number of pulses in this measurement is greater than the number dialed ia to decoder 16, then a signal will be output from the decoder that will flip the trigger 17 into the zero state. At that, the switching off signal from the head 10 will not pass through the AND 18 element, and the digits of the counter 14 will not reset to zero. If the number of pulses in this measurement is less than the number to which the decoder 16 is set, then the signal does not appear at the output of the decoder 16 . In this case, the switching off signal from. heads 10 will pass through the element and 18, since at its second input there will be a single signal from trigger 17, and the corresponding bits of counter 14 will be reset to yule.

Thus, the accumulation of pulses in the counter 14 will occur only if the number of pulses during a single measurement of the analog signal is more than that the decoder 16 is set to.

FIG. Figure 2 shows the output signal (in pulses) of the proposed conveyor scale with a single measurement of a scientific research institute depending on the input value of the measured analog signal (in pulses). The dead zone size can easily be changed by the appropriate setting of the decoder 16.

Claims (2)

1. USSR author's certificate 158431, cl. G 01 G 23/36, 1962, 2. USSR author's certificate number 328774, cl. G 01 G 23/36, 1974 (prototype). .