SU1531078A2 - Device for regulattion of temperature - Google Patents

Abstract

The invention relates to the control of non-electric quantities and can be used in various technological processes, where the heating of raw materials, products or equipment is carried out by supplying a liquid or gaseous heat transfer fluid, controlled by a pulsed electromagnetic valve. The purpose of the invention is to increase the reliability of the device by eliminating false positives. The device contains a sensor 1 and the setting device 2 connected to the inputs of the comparator 3. The output of the comparator 3 is connected through the matching elements 4.5 to the input of the differentiating unit 6, as well as to the first input of the amplifier 10 and the input of the inverter 7 connected to the first input. The second inputs of the amplifiers 10, 11 are connected to the output of the switch 15, and the outputs to the control windings 13, 14 of the pulse solenoid valve. The single-vibration 8.9 are connected by inputs to the output of the differentiating unit 6 and the outputs to the inputs of the EXCLUSIVE OR 12 element, the output of which is connected to the control input of the key 15. 1 Il.

Description

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The invention relates to the control of non-electric quantities, can be applied to automatically control the temperature in the chemical, food and other industrial sectors and is an improvement of the invention according to the author. No. 543926.

The purpose of the invention is to increase the reliability of the device by eliminating the false positives of the electromagnetic unloading valve.

The drawing shows a diagram of the device.

The device contains a sensor 1, a sensor 2, a comparator 3, matching elements 4 and 5, differentiating unit 6, inverter 7, first 8 and second 9 single vibrators, amplifiers 10 and 11, element ISKHAOCA1EDEE or 12, windings 13 and 14 of the electromagnetic discharge valve key 15.

The device works as follows.

When the temperature of the controlled object decreases to a predetermined threshold of the device response, a low voltage level appears at the output of the comparator 3. This leads to the fact that a low voltage level appears at the first input of the amplifier 10 (base of the transistor), and a high voltage at the first input of the amplifier 11. At the same time, the differential unit 6 on the falling edge of the signal at the output of the comparator 3 generates a pulse that triggers the first 8 and second 9 one vibrators. The output of the second one-oscillator 9 changes from the state of logical zero D to the state of the logical unit for the time T chosen such that it exceeds the duration of the interference. The output of the first one-vibrator 8, the transition from the state of a logical zero to a state of a logical unit for a time equal to the sum of time T, and the response time of valve T. As a result, the output of the logic element EXCLUSIVE lUIH J2 with a delay equal to T appears the level of a logical unit of duration T, which opens the key 15. As a result, a current flows through the winding 14 of the valve for a time Tc. The valve is triggered to open, for example, the main pipeline of the heating unit and is self-blocked in. open position

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for the duration of the change in the heat balance of the regulation. Upon termination of the control pulse of the first one-shot 8, the key 15 is locked, stopping the flow of current through the winding 14.

With 1: Ovity of the object to be controlled to a predetermined release threshold of the device, the voltage of sensor 1 becomes greater than the voltage of setting device 2, and a high voltage level appears at the output of comparator 3. As a result, a high voltage level appears at the first input of amplifier 10, and a low voltage at the first input of amplifier 11. Differentiating unit 6 forms a pulse at the leading edge of the signal at the output of comparator 3, which triggers one-shot 8 and 9. Analogously indicated open It is set to 1 pin 15, and this leads to the fact that valve winding 13 is for a time T j. current flows. The valve closes and locks in this position. After closing the key 15 (through time T kl), the flow of current through the winding 13 stops.

In the case of a short-time false triggering of the comparator 3, the signal from its output through the match 1 1st element 5 and the differentiating unit 6 enters the inputs of the one-shot 8 and 9 and starts them. Since the pulse duration at the output of the second single vibrator 9 (T) is chosen longer than the duration of the interference, the element IS1 SHOUGHUGCH OR 12 opens the key 15 when the signals at the first inputs of the amplifiers 10 and 11 return to the state they were before interference. Consequently, a false positive does not occur.

Thus, the time between failures of the solenoid valve is increased, the possibility of installing the latter in an indefinite state is eliminated, and consequently, the reliability of the entire device is improved.

Claims (1)

Claims of the Invention A device for temperature control according to the author. No. 543926, due to the fact that, in order to increase the reliability of the device, it contains a second one-shot and an EXCLUSIVE OR element, and the input of the key element is connected to 51531078 one-shot outlets through the wand element of the first one-shot for the time ISU, 1 second, and the second single-actuation of the electromagnetic breeder, the time of the loaded valve, is connected to the input selected by a large time using the first one-shot.