SU591840A1 - Temperature regulator - Google Patents

Description

(54) DEVICE FOR REGULATING TEMPERATURE

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. The invention relates to the field of automation, namely to contactless devices for regulating electrical resistance in a consumer's power load circuit and related values, such as temperature, humidity, pressure.

Devices are known for adjusting electrical parameters, including electrical resistance, and values of l functionally associated with them.

However, in such devices, electromechanical elements in the form of relays, contactors, etc., whose moving parts wear out and go out of service relatively quickly, are used as controls and switching. During operation, these elements are a source of electrical and acoustic interference, which requires the use of special protective measures. The relatively large dimensions and weight of these elements lead to an increase in the weight and dimensions of the regulating devices as a whole. All this greatly reduces the reliability and service life of the regulating devices, and, moreover, requires

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frequent routine inspections and repairs.

The closest technical solution to the invention is a device for temperature control, which contains a temperature-sensitive unit, an actuating element made in the form of anti-parallel thyristors, in series with which a heater is connected to the AC source, and transistor control unit 2,

The disadvantage of the device is its complexity.

The aim of the invention is to simplify the device.

This goal is achieved by the fact that in the proposed device the emitters of the transistors of the control unit are connected to the cathodes of the thyristors, the transitions of the cathode control electrode of each of which are in series with the transitions of the collector-emitter of the transistors of the control unit connected to the direct current source Thermal block.

Claims (1)

The drawing shows the principal electrical circuit of the proposed device. It contains an actuating element on thyristors 1.2, transistors 3.4 of the control unit, resistors 5 separating diodes 9-12, sources of direct current 13-15 and an indicator box 16, an alternating current source temperature-sensitive unit 18 (sensor) And a heater 19. The device works as follows. If the air temperature in the litter of the scientific research institute is below the limit, the value of which is set on the sensor, then its contacts are once: 1 ktuty-and transistors 3 and 4 are in the open state, in which the emitter-collector j transition resistance is not minimal. Conditions for current to flow through two closed circuits First circuit: plus source 13, control electrode and cathode of thyristor 2, emitter and collector of transistor 3, minus source of 13, second circuit plus source 14, thyristor 1, transistor 4 and minus of source 14 At set values These sources 14 and 13, for example, flow through the post-switch for unlocking the thyristors and 2, which is determined mainly by their resistance of the junction control electrode-cathode. In the open state of the thyristors, the cathode – anode flow resistance is negligible. Since the thyristors are interconnected counter-parallel with each other, and the circuits with the heater and the electrical network are in series, when the thyristors are open, almost the entire voltage of the electrical mains is applied to the heater. This produces heat. If the medium temperature slightly exceeds the value that was installed on the sensor, then its contact pair goes into a closed state and creates the condition for the current to pass through the circuit: plus source 15, isolation diodes 9 and 10, resistors 5 and 7, resistors b and 8, diodes 11 and 12, thermosensitive unit and minus source 15. When current flows through the circuit on resistors 6 and 8, a voltage drop is created which is applied to the collector-base junction by transistor 3 and this voltage completely blocks the transistors 3 and 4 that its their transitions emitter-collector break. thyristor control circuits 1 and 2 from sources 13 and 14. At the same time, the anode – cathode resistance of thyristors 1 and 2 sharply increases to tens of thousands of ohms, and the alternating voltage of the power grid will be fully applied to the thyristors, and the voltage on the heater is negligible . When this heating is not. In the heating mode, when almost all the voltage of the electrical network is applied to the heater, some voltage drop of about 2-3 V remains on the thyristors and creates a counter current to the sources 13 and 14. At the same time, the voltage of the sources stabilizes when the voltage of the electrical network varies in limits il5%. The proposed device can be used to control the temperature in electric heaters and boiler installations, in everyday life for individual heating systems, in thermostats of various power, etc. With the help of this device it is possible to smoothly adjust the electrical resistance in the load circuit of the consumer, for this it is necessary to use a sensor with a smooth change of resistance or voltage at its output. The magnitude of the power consumption of the connected load to the device is selected and depends only on the type of thyristors used in the circuit. Reliability and durability of the proposed device is enhanced. In addition, the device is silent in operation. The device uses a high-resistance input of 40-50 kΩ for connecting sensors. Sensor control currents are measured in micro amperes, which allows remote control of the device. At the same time, the length of the control signal transmission line from the sensor to the device can reach hundreds of kilometers. The design of the device is simple, does not require adjustments during operation, and ensures sufficient stability of operation when the power supply voltage changes. The adjustments are carried out during the manufacture of the device. During operation, the device does not require special maintenance and systematic supervision. The device has relatively small cost, size, and weight, which are mainly determined by the cost, dimensions, and weight of the thyristors used. The invention includes a temperature control device comprising a temperature-sensitive unit, an actuating element made in the form of anti-parallel-connected thyristors, in series with which an heater is connected to the AC source, and a transistor control unit, characterized in that, to simplify the device, the transistor emitters control unit connected to the thyristor cathodes, transitions cathode Each electrode has a 1,. ryh in series with the switch-emitter junction of the transistors of the control unit are connected to a source of constant current, and the output of the heat-sensitive unit is connected to the base-5 junction junctions of the transistors. Sources of information: taken into account in the examination: 1Authorial certificate of the USSR p 115691, G05 D 23/00, 1965. 2 Certificate of the USSR 238917, 42 a 2/05. 1969. -v Network