SU890369A1 - Pneumatic device for control of batch-metering process - Google Patents

Description

(5) PNEUMATIC DEVICE TO CONTROL THE DOSING PROCESS

The invention relates to instrumentation, namely to pneumatic devices for controlling the dosing process, and can be used in the mechanical, food and chemical industries. Pneumatic devices of similar purpose are known that have a complex structure 1. The closest technical solution to the present invention is a pneumatic device containing a sensor for the level of the dosed reagent, the output of which is connected to the input of the first memory element and the negative chamber of the first comparison element, the plus chamber of which is connected with the output of the adder, and the output through the OR element with the erase input of the first trigger, the plus chamber of the adder is connected to the output of the first memory element, The pneumatic button is connected to the first trigger input, and the second trigger nozzle is normally opened with the control chamber of the first memory element and the device output, the second trigger feed channel is connected to the switch, the output is connected to the second OR input. the output of the second reference element, the minus chamber of which is connected to the output of the source reagent concentration sensor, and the positive one - to the setting unit 2}. The drawbacks of the known device are the presence of preparatory operations and the dosing process which increases the time. The purpose of the invention is to reduce the dosing time. This goal is achieved by the fact that the device includes a series-connected level sensor of the initial reagent, a multiplication unit and a second memory element, the control chamber of which is connected to the output of the device, and the output with the minus chamber of the adder.

The drawing shows a schematic diagram of the proposed device.

The device contains a level 1 sensor in the measuring device 2 with the reagent being metered, the first memory element 3, the first comparison element k, the level 5 sensor in the device 6 with the initial reagent, multiplication unit 7, the second memory element 8, the adder 9, the element OR 10, the first and second triggers 11 and 12, the switch 13, the pneumatic button 1, the sensor 15, the concentration of the source reagent, the second element 16 of comparison and preset | .1k 17. The output PA p of the level sensor of the dosed reagent is directly connected to the negative chamber of the first element k of comparison through the first element 3 pa TI - with the plus chamber of the adder 9, to the plus chamber of which the source reagent level sensor 5 is connected, the multiplication unit 7 and the second memory element 8, the output of the adder 9 is connected with the plus camera of the first comparison element 4, which output through the OR element 10 connected to the erase input of the first trigger 11, the installation input of which is connected to the pneumatic button, and the output through the normally open nozzle of the second trigger 12 to the output channel of the device Pg, | .jj. The inputs of the second comparison element 16 are connected to the output of the concentration sensor 15 of the initial reagent and the setting device 17, and the output to the installation input of the second trigger 12, the power supply channel of which is connected to the output of the switch 13 and the output to the second input of the OR element.

The device works as follows.

The pneumatic button 1 turns on the first trigger 11, the output of which through the normally open nozzle of the second trigger 12 acts on the regulating member 18, allowing the inlet of the dosed reagent to the apparatus 6. At the same time, the discrete output signal Pgjjji turns on the first and second memory elements, so that the inputs of the adder are fixed signals R.d. and Kpjp. where, is the pressure at the outputs of sensors 1 and 5 at the moment of the start of dosing; K - coefficient of proportionality, set

block 7 multiply. In accordance with the switching scheme, the supply of the dosed reagent continues until the level change in the measuring device 2 reaches a predetermined value determined by the initial level in the device 6, i.e. R. - R

1 1.P

.R. L.R.

where f is the outgoing level value

When the required equality is achieved, the first comparison element is triggered, resetting the first trigger 11 to zero, respectively, the output signal of the device P accepting the zero value and the supply of the dosed reagent is stopped. In addition to the main function, the device also provides a lock to achieve the lowest possible concentration of the initial reagent in the apparatus 6. The lock is turned on using the switch 13, which switches its second trigger 12 to the power channel. When the oncentration limit is reached, set by the setting device 17, the second comparison element 16 is triggered, the state of which is stored on the second trigger 12. In this case, the single signal at the output of the second trigger resets the first trigger to zero, thereby closing the dispensed reagent supply valve 18.

By reducing the preparatory steps associated with measuring the level in the apparatus and setting the dose, the dosing time is reduced by about 20%.

Claims (1)

Invention Formula A pneumatic device for controlling the dosing process, containing a level sensor of the dosing reagent, is connected via its output to the input of the first memory element and the negative chamber of the first element, the plus chamber of which is connected to the output of the adder, and the output through the OR element with the erase input of the first trigger, the plus chamber of the adder connected to the output of the first memory element, a pneumatic button is connected to the installation input of the first trigger, and its output is via a normally open nozzle of the second trigger is connected to the control camera of the first memory element and the output of the device, the power channel of the second trigger is connected to the switch, the output is from