SU767724A1 - Temperature control device - Google Patents

Description

(54) DEVICE FOR REGULATING TEMPERATURE

I

The invention relates to the field of automatic control, in particular, to devices for temperature control with optimization of the mode of thermoelectric elements.

A device for temperature control is known, comprising a temperature sensor, a power amplifier and thermoelectric coolers 1.

The disadvantage of this device lies in its low efficiency, since a current flows through thermoelectric coolers that does not correspond to the extreme value of the temperature difference during cold and hot sleeves of thermoelectric elements.

The closest in technical essence to the invention is a device for temperature control, comprising a control panel and a first temperature sensor connected in series, a power amplifier and a thermoelectric cooler 2.

This temperature control device is not economically efficient due to the inefficient conversion of electrical energy in thermoelectric coolers.

The purpose of the invention is to increase the efficiency of the temperature control device.

To achieve this goal, a sequential connected OR-NOT element, a time relay and a delay unit connected in series to a second temperature sensor, a normalizer, and a serially connected element are inserted into the device for temperature control, which contains a control panel and serially connected first temperature sensor, power amplifier and thermoelectric cooler. memory and comparison unit, the second input of which is connected to the output of the normalizer, and the third input and outputs -

15, respectively, with the second output and the second and third inputs of a time relay, the fourth input of which is connected to the first output of the control panel, the third and fourth outputs to the corresponding inputs of the memory unit, and the fifth output to the second input of the delay unit whose output is connected to the second input of the power amplifier, the output of the first temperature sensor is connected to the first input of the element OR NOT, the second

the output of the control panel - with the fourth input of the memory block, the third output - with the second input of the element OR NOT.

The drawing shows a functional diagram of the device for temperature control.

The temperature control device includes a remote control 1 and a series connected first temperature sensor 2, a power amplifier 3 and a thermoelectric cooler 4, an OR-NOT 5 element connected in series, a time relay 6 and a delay unit 7 connected in series a second temperature sensor 8, the normalizer 9, memory unit 10 and comparison unit 11.

The device works as follows.

In the presence of the signal "1 on one of the inputs of the element OR NOT 5 on its Output, the signal disappears. The time relay 6 is reset to its original position. At the quarter-time output of the time relay 6, a constant-time control signal appears in the memory recording unit 10 of the total emf value of the second temperature sensor 8 proportional to the temperature on the surface of thermoelectric coolers 4 and converted by the normalizer 9 to a standard signal. At the end of the first time delay, the second adjustable time delay begins to reduce the phase shift of the power amplifier 3, which is predetermined by the value of the supply voltage (current).

Thus, at the first time relay output b, during the period of the second time delay, there is a control signal applied to the first input of the delay unit 7, at the output of which the phase shift varies as a function of the thermoelectric efficiency of the material of the thermoelectric elements, the set cooling temperature in the chamber and at the input amplit. and 3 power. During the second time delay, the amplifier 3 changes the phase of the voltage on the control electrodes of the thyristors depending on .. From; the output voltage of the temperature sensor 8 in the thermostatically controlled mode. Decreasing the second time delay leads to an increase in the average component of the voltage supplying thermoelectric coolers 4 and, consequently, the current. After the end of the second time delay, the relay 6 switches to the third constant time delay. In this case, the control voltage from the second time relay 6 is supplied to the third input of block 11, which compares the levels of the signals at the output of memory block 10 and the output of the normalizer 9, i.e., the temperature levels of the enhanced current supply and current to change it.

The result of the comparison may be options. Option 1. ,

IJ,;, + -,

di;

either u,.

where Ui is the signal level until the power supply current of thermoelectric coolers 4 increases;

d1 / 1 - adjustable signal increment level after current change

nutrition

At the same time, at the outputs of the comparator unit 11, the signals "O and after the end of the third time delay and relay 6" are reset to their original position. Option 2. U, 7 | +.

In this case, at the first output of the comparison unit 11, the signal "1, the second and third exposure of the time relay 6 is repeated until the conditions of option 1 are obtained. Option 3. l / i U; - ALT ,.

0 In this case, at the second output of unit 11 of the comparison signal, "1" and after the end of the third shutter speed relay 6, it turns on for the fourth adjustable time delay. As a result, a control voltage arises at the fifth output of the time relay 6 and at the input of the delay unit 7, which increases the duration of the time delay and, therefore, reduces the supply current of thermoelectric coolers 4, a third, and a quarter of the time relay

0 is repeated until the conditions of option 1 are obtained.

The initialization of the time relay corresponds to the choice of the optimal supply current of thermoelectric coolers 4. After this, the time relay switches on for the fifth adjustable delay between cycles, which the memory unit 10 returns to its initial state, at the end of its operation it repeats when there is a signal "1 at one of the inputs of the element

Q OR-NOT 5 .. By pressing the reset button of the remote control 1 of the relay 6, the time is reset. When the start button of the control panel is pressed, the memory unit 10 is reset, and then the operation proceeds as described. Introduction of optimization of the power supply mode of thermoelectric elements by comparing the cooling capacity of thermoelectric elements with a change in the supply current and before its change, adjusting the time of the off state of the power amplifier 3. Depending on the thermoelectric efficiency of the material of thermoelectric coolers 4 and the set cooling temperature in a thermostatically controlled chamber, increases the efficiency of using elements by 20%, the accuracy of temperature control in the object by 18 ° / o, the service life of thermoelectric coolers by 15%; the switching of elements is simplified by 20%.

Claims (1)

Invention Formula A temperature control device comprising a control panel and a serially connected first temperature sensor, a power amplifier and a thermoelectric cooler, characterized in that, in order to increase the efficiency of the device, it contains an OR-NOT element connected in series, a time relay and a delay unit sequentially connected to the second temperature sensor, normalizer, block of memory and block comparison, the second input of which is connected to the output of the normalizer, and the third input and outputs - according to Responsibly with the second output and the second and third time relay inputs, the fourth input of which is connected to the first output of the control panel, the third and fourth outputs to the corresponding inputs of the memory unit, and the fifth output to the second input of the delay unit whose output is connected to the second input of the power amplifier, the output of the first temperature sensor is connected to the first input of the OR-NOT element, the second output of the control panel is connected to the fourth input of the memory unit, the third output is connected to the second input of the OR-Hb element. Sources of information taken into account during the examination 1. US Patent No. 3,244,418, cl. 62-3, publish 1968.r-f-f-r, 2 Copyright certificate № 560214, cl. G 05 D 23/19, 1974 (prototype). P