KR100285884B1 - Thermostat for environmental test - Google Patents

Abstract

PURPOSE: A thermostat for environmental test is provided to reduce size and weight of thermostat, while achieving improved portability and reducing test space. CONSTITUTION: A thermostat comprises a chamber(10) having a heat insulating material filling the gap between an inner container(11) and an outer container(12), a door(14) arranged at the front surface of the chamber, and a refrigerating unit(20) and a heater mounted inside of the chamber; a control unit(40) connected to the refrigerating unit and the heater through an electrical circuit; a display unit(50) connected to the control unit, and which displays input and output values of the control unit. The inner container is made up of a heat conductive material having a heat conductivity of 200(kcal/m.h.Deg.C) or higher. The refrigerating unit includes a plurality of thermoelectric semiconductors(21) each of which has a cold heat surface(21a) attached to the outer surface of the inner container. The inner container has a ceramic layer(11a) formed by depositing a ceramic material to the inner surface of the inner container.

Description

Thermostat for environmental test

The present invention relates to an environmental test thermostat using a thermoelectric semiconductor, and more particularly to an environmental test thermostat used to test a change in the nature or state of a material in a chamber of a low temperature or high temperature atmosphere by testing materials such as various mechanical parts and paints. It is about.

In the chamber provided with a conventional environmental test chamber, a refrigeration unit is installed together with a heater. The refrigeration unit includes a compressor, a condenser, an expansion valve, and the like, and the pipes are connected to each other so that the refrigerant is circulated to cool the chamber of the chamber. To make it work.

The conventional thermostat is made of stainless steel having a thermal conductivity of 22 (kcal / m.h. ° C.) of the chamber, so that when the temperature of the chamber is severe, condensation occurs and the time required for reaching the set temperature is high. For example, it takes about 70 minutes to raise a chamber of 300 × 300 × 300 mm from minus 50 ° C to 180 ° C by operating a heater. It takes about 140 minutes to descend from 50 ℃ to minus 50 ℃.

Moreover, the performance of the cryogenic environmental test thermostat requires an evaporation temperature of minus 70 ° C or lower. However, in order to satisfy these conditions, there are limitations in general refrigeration methods. The so-called two-way freezing method, which is performed by separating the low-temperature side and the high-temperature side, is a situation in which the two-way refrigeration thermostat for environmental testing is more complicated in structure, and the manufacturing cost and maintenance cost are very high.

In addition, the conventional refrigeration unit mounted on the air conditioner, such as a thermostat is difficult to take measures when the refrigerant gas leaks, the air is polluted, and the structure of the refrigeration unit is complicated, it is cumbersome and expensive to repair and replace when the failure occurs. In addition, the large volume and weight occupied by the refrigerating device are inconvenient to move the device and occupy a lot of space.

The present invention has been made in view of the above disadvantages, and to provide an environmental test refrigeration apparatus using a thermoelectric semiconductor as a refrigeration apparatus.

1 is a partially cutaway perspective view of the present invention.

2 is a vertical cross-sectional view of the present invention.

3 is a horizontal cross-sectional view of the present invention.

Explanation of symbols on the main parts of the drawings

10; Chamber 11; Enclosure 11a; Ceramic layer 11b; Ventilation passage

12; Enclosure 13; Insulation 14; door

15; Projection window 20; Freezer 21; Thermoelectric semiconductor

21a; Cold cotton 21b; Heating surface 30; heater

31; Blower fan 40; A controller 50; Display

60; Duct 61; Vents 70; temperature Senser

The present invention is characterized in that the chamber (10) is filled with a heat insulating material (13) between the inner box (11) and the outer box (12), the door (14) is provided at the front, and the refrigerating device (20) and the heater (30) are mounted. And a control unit 40 connected to the refrigerating device 20, the heater 30, and the electric circuit, and a display unit 50 connected to the control unit 40 to display input and output values of the control unit 40. In the thermostat for an environmental test including, the inner box 11 uses a thermally conductive metal material having a thermal conductivity of 200 (kcal / mh ° C.) or more on one surface or the entire surface thereof, and the refrigerating device 20 includes a plurality of thermal conductors 21. By attaching the cold heat surface 21a of the thermoelectric semiconductor 21 to the outer surface of the inner box 11, the circuit is configured in parallel and electrically connected to the control unit 40.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a partially cutaway perspective view of the present invention, FIG. 2 is a vertical sectional view of the present invention, and FIG. 3 is a horizontal sectional view of the present invention.

As shown in Figures 1 to 3, the environmental test thermostat according to the present invention is filled with a heat insulating material 13 between the inner box 11 and the outer box 12, the front door 14 is provided and the refrigerating device 20 ) And a chamber 10 equipped with a heater 30, a controller 40 electrically connecting a circuit to the chamber 10 and the heater 30, and a controller 40 connected to the controller 40. It includes a display unit 50 for numerically displaying the input value and the output value.

Reference numeral 15 is an 'projection window'.

The inner box 11 is preferably a part or whole of the heat conductive metal material having a thermal conductivity of 200 (kcal / m.h. ° C.) or more, and uses aluminum having a thermal conductivity of 204 or copper having a thermal conductivity of 333.

A ceramic layer 11a coated with ceramic is formed on the inner surface of the inner box 11, and the inner layer 11 of the inner layer 11 can withstand the inner box 11 without thermal deformation even at a high temperature and the temperature distribution of the inner box 11. Can be reduced to ± 0.3 ℃.

A plurality of thermoconductors 21 are provided and attached to both sides of the inner and outer sides of the inner box 11 made of a thermally conductive metal.

In the illustrated inner box 11, six thermoelectric semiconductors 21 were attached to one surface thereof. The thermoelectric semiconductor 21 is attached to the outer surface of the cold surface 21a, that is, the low temperature side of the inner box 11 by using a high-performance type that generates cold heat of less than 70 degrees Celsius or less, and the cathode terminal and the anode terminal are electrically connected in parallel. A circuit is configured and connected to the controller 40. When attaching the heat conductor 21 to the inner case 11, by applying a very high thermal conductivity silver (chemical symbol; Ag) on the attachment surface of the inner case 11 can maximize the heat transfer function.

In addition, between the inner box 11 and the outer box 12, the heat insulating material 13 is filled and the duct 60 is formed at the same time. And the inner box 11 is equipped with a temperature sensor to measure the internal temperature of the inner box (11).

As an example of the heat insulating material 13, asbestos, etc. may be used, and the illustrated duct 60 is connected to a vent hole 61 formed in the enclosure 12, and the vent hole 61 may be equipped with a heat radiating fan as necessary. .

On the other hand, the lower portion of the inner box 11 is formed with a blowing passage (11b) in communication with the duct 60, three blowing fans 31 are arranged in a row on the upper portion of the chamber 10, each fan is a duct It is arranged at 60. And the heater 30 is arrange | positioned in the duct 60 so that it may be located below the blower fan 31. As shown in FIG.

The control unit 40 is a circuit configured to control the temperature of the thermoelectric semiconductor 21 with voltage and current, and can use a microcomputer, a power supply circuit, an AD converter, a current / voltage control switch, an amplifier, a thyristor (constant temperature circuit) ), A control integrated circuit equipped with a timer and an overload breaking circuit can be used. The control unit 40 is electrically connected to the temperature sensor 70 and the display unit 50.

Referring to the operation of the present invention having such a configuration as follows.

When the test material is to be tested in a low temperature environment with a thermostat according to the present invention, a predetermined current and voltage may be applied to the thermoelectric semiconductor 21 by a control operation of the controller 40. The series of thermoelectric semiconductors 21 to which a predetermined current and voltage are applied have both sides of the heat conduction and the exothermic action, respectively, and the cold heat generated from the cold surface 21a of the thermoelectric semiconductor 21 is conducted to the enclosure 11 The chamber 10 is constructed in a low temperature environment by being radiated into the interior of the chamber 11.

When cold heat is generated on the cooling surface of the thermoelectric semiconductor 21, heat is generated on the heat-generating surface 21b, which is the opposite surface. In this case, the hot air is discharged through the air vent 61, and the cold air flows into the duct 60 so that the semiconductor 21 is removed. Cooling surface 21b of the) is cooled.

The time that the interior of the enclosure 11 reaches the low temperature atmosphere may vary depending on the set temperature, the volume of the chamber 10, and the performance and number of the thermoelectric semiconductors 21. However, the volume of the enclosure 11 is 300 × 300. It took 140 minutes to lower the chamber 10 having a size of 300 mm from the image 100 ° C. to minus 70 ° C., but the present invention took about 20 minutes under the same conditions.

When the test material is to be tested in a high temperature environment, the driving of the thermoelectric semiconductor 21 is stopped and the heater 30 is operated. The operation description of the heater 30 is the same as in the related art and thus will be omitted.

As described above, in the present invention, since the thermoelectric semiconductor 21 is adopted as the refrigerating device 20, the appearance of the chamber 10 can be greatly reduced compared to the conventional thermostat having a compressor, a condenser, and the like. It is possible to manufacture a small size and light weight of the thermostat, so it is convenient to move and take up the experiment space.

In the present invention, since the refrigerant is not used, there is no fear of contamination due to gas leakage, and since the inner box 11 of the chamber 10 uses a thermally conductive metal material having a thermal conductivity of 200 (kcal / mh ° C.) or higher, Even if the temperature changes rapidly, condensation does not occur and the time to reach the set temperature is shortened.

In addition, by using the thermoelectric semiconductor 21 to form the inside of the chamber 10 in a low temperature atmosphere by controlling current and voltage, not only can the temperature control be finer but also the time for reaching the set temperature is shortened.

In addition, the present invention has the advantage that the structure of the thermostat is simple, there is almost no failure, and the repair is simple and the maintenance cost is reduced.

Claims (3)

A chamber 10 filled with an insulating material 13 between the inner case 11 and the outer case 12, the front door 14 having a front side, and a refrigerating device 20 and a heater 30 mounted thereon; 20) and an environmental tester including a control unit 40 connected to a heater 30 and an electric circuit, and a display unit 50 connected to the control unit 40 and displaying an input value and an output value of the control unit 40. In The inner box 11 uses a thermally conductive metal having a thermal conductivity of 200 (kcal / mh ° C.) or higher on one surface or the entire surface thereof, and the refrigerating device 20 includes a plurality of thermal conductive conductors 21 of the thermal conductor 21. An environmental test thermostat characterized by attaching a cold heating surface (21a) to the outer surface of the inner box (11) and simultaneously configuring a circuit in parallel with the control unit (40). The thermostat for environmental tests according to claim 1, wherein a ceramic layer (11a) is formed by applying ceramic to the inner surface of the inner box (11). The thermostat according to claim 1, wherein the inner box (11) is copper or aluminum.