JPH04191638A - Apparatus for thermal shock test - Google Patents

Abstract

PURPOSE:To enable efficient heating of a drain pipe in accordance with temperature and to reduce a cooling load in a precooling chamber by a construction wherein a heater disposed in the drain pipe is made to conduct a defrosting operation corresponding to the set number of times, the set time for heating, etc. CONSTITUTION:A testing chamber 3, a precooling chamber 4, a preheating chamber 5, etc. are provided in a housing 1 and they are insulated thermally by a heat-insulating wall 2 respectively. A cold storage chamber 9 is provided and a vaporizer 6 of a refrigerant and a cooling fan 7 are provided in the precooling chamber 4, as a cooling means 10 for cooling the cold storage chamber 9 and the testing chamber 3. Herein the vaporizer 6 and the cold storage chamber 9 are at low temperatures and tend to be frosted, and a hot gas is introduced into the vaporizer 6 so as to conduct a defrosting operation. Drainage is sent to a drain pan 11 and further to a drain pipe 12 wherein a heater 13 having a control means 14 is disposed. On the other hand, a heater 20 and a heating fan 21 for heating the inside of the testing chamber 3 are provided in the preheating chamber 5. The contact of a door 25 of the testing chamber 3 with the heat-insulating wall 2 is sealed up airtightly, and inside the housing 1, a detecting means 35 for detecting a time point of start of heating of the heater 13 from the number of times of thermal shocks is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an apparatus for carrying out a thermal shock test by repeatedly changing the temperature of a test chamber alternately between a cold exposure temperature and a hot exposure temperature.

BACKGROUND OF THE INVENTION A conventional thermal shock testing device is disclosed in, for example, Japanese Unexamined Patent Publication No. 1-2
It is shown in '74035 public relations. In such a thermal shock test apparatus, a heat shock cycle can be repeatedly performed in which the temperature of the test chamber is rapidly changed alternately between a low temperature exposure temperature and a high temperature exposure temperature. By storing a test object in a test chamber and repeatedly subjecting it to heat shock, that is, cold shock, the durability and reliability of the test object can be tested at an accelerated pace.

In a thermal shock test apparatus, a pre-cooling chamber and a pre-heating chamber are provided separately from the test chamber in order to rapidly change the temperature within the test chamber. The precooling chamber is precooled to a temperature lower than the low temperature exposure temperature, and when cooling the test chamber to the low temperature exposure temperature, the cold air in the precooling chamber is circulated within the test chamber. The preheating chamber is preheated to a temperature higher than the high temperature exposure temperature, and when the test chamber is brought to the high temperature exposure temperature, hot air in the preheating chamber is circulated into the test chamber. In this way, the temperature within the test chamber is rapidly cooled or heated.

The inside of the precooling chamber is cooled to 0° C. or lower. Therefore, an evaporator or the like is provided that absorbs the surrounding heat and cools it by evaporating the refrigerant. Frost easily adheres to the evaporator and other parts. When frost builds up, the circulation of cold air and the absorption of heat from the surroundings are inhibited, reducing cooling capacity. Therefore, each time a predetermined number of thermal shocks is reached, a defrosting operation is performed. In the defrost operation, frost in the evaporator is melted by a hot gas defrost method, and is removed by dropping it as drain.

A thermal shock test consists of multiple thermal shock cycles. Therefore, defrost operation is performed every fixed number of times.

Problems to be Solved by the Invention In the thermal shock testing device, the precooling temperature is -40 to -5.
It reaches around 0℃. At such low temperatures, the amount of moisture that can be contained in the air is extremely small. Compared to this amount, air at room temperature contains a large amount of water even if the relative humidity is low. Since it is difficult to make a test room completely airtight, it is not possible to completely prevent moisture from entering the test room from around the test room. Also,
Some test standards require that the test chamber be opened for a certain period of time during thermal shock to maintain room temperature. The moisture introduced into the test chamber in this manner adheres as frost to the evaporator and the like in the precooling chamber when cooling the test chamber.

In order to remove the moisture that has settled in the precooling chamber, a defrosting operation, that is, a Tefrost operation is performed. In the defrost operation, the evaporator is heated by a pot gas defrost method or the like to melt adhering frost and allow it to fall as drain. The fallen condensate is stored in the lower part of the precooling chamber. In the prior art disclosed in Japanese Unexamined Patent Publication No. 1-274035, air around the device is introduced for defrosting. Therefore, the amount of frost that adheres to the evaporator and the like during precooling operation increases, and the amount of moisture that becomes drain and is stored during defrosting also increases.

The precooling chamber is provided with a drain pipe for discharging the drain to the outside. The drain pipe is always filled with water to prevent air and heat from entering from the outside through the drain pipe. However, since the temperature in the precooling chamber becomes low, the water in the drain pipe freezes.

If the water in the drain pipe is frozen, the drain cannot be drained during defrost operation. Therefore, in order to prevent the drain pipe from freezing, a heater is provided to heat the drain pipe. If the heater is constantly heated, the drain pipe will not freeze, and water can be drained during the defrost operation of the pre-cooling chamber.

However, the I
・Continuously heating the tube increases the load for cooling the pre-cooling chamber.

The object of the present invention is to be able to effectively drain drains,
It is an object of the present invention to provide a thermal shock testing device capable of reducing an increase in load on a precooling chamber due to heating by a heater.

Means for Solving the Problems The present invention performs a thermal shock test by alternately supplying cold air from a pre-cooling chamber and hot air from a pre-heating chamber to a test chamber. A cooling means for cooling the precooling chamber to a lower precooling temperature and a drain pipe for discharging the drain are provided, and each time the number of thermal shocks reaches a predetermined number N, the cooling means is operated to defrost. and
In a thermal shock testing device in which a drain pipe is provided with a heater, the detection means detects that the number of thermal shocks until the number of defrosting operations is reached is equal to or less than a preset number m, and the detection means The thermal shock test apparatus is characterized in that it includes a control means for controlling heating of the heater of the drain pipe in response to an output from the drain pipe.

Further, the present invention is characterized in that the number m preset in the detection means is set larger as the low temperature exposure temperature or the precooling temperature becomes lower.

Furthermore, the present invention performs a thermal shock test by alternately supplying cold air from the precooling chamber and hot air from the preheating chamber to the test chamber, and the precooling chamber is precooled to a precooling temperature lower than the low temperature exposure temperature of the test chamber. A cooling means for cooling the room and a drain pipe for discharging the drain are provided, and each time the number of thermal shocks reaches a predetermined number N, the cooling means is defrosted, and the drain pipe is In a thermal shock test apparatus provided with a heater, a detection means for detecting that a thermal shock time until the number of defrosting operations is reached is less than or equal to a preset time W; and an output from the detection means; The thermal shock test apparatus is characterized in that it includes a control means for controlling the heating of the heater of the drain pipe in response.

Further, the present invention is characterized in that the time W preset in the detection means is set longer as the low temperature exposure temperature or the precooling temperature becomes lower.

Function According to the present invention, the cooling means of the precooling chamber is operated for defrosting every predetermined number N of thermal shocks. The detection means detects that the number of times of thermal shock until reaching the number of times of defrosting operation is less than or equal to a preset number of times m. The control means controls the heating of the heater provided in the drain pipe in response to the output from the detection means. In other words, the drain pipe is heated a predetermined number of times m (Jβ due to the preceding thermal shock) after the defrosting operation. Therefore, when the defrosting operation is started, the water in the drain pipe is sufficiently melted. The defrosting operation makes it possible to sufficiently drain the condensate generated in the precooling chamber.Also, since the heater is heated for a period of thermal shock less than m after the defrosting operation, the cooling means for the precooling chamber is heated. The increase in load is small.

Further, according to the present invention, heating by the heater is started from a faster number of thermal shocks as the low temperature exposure temperature of the test chamber or the precooling temperature of the precooling chamber becomes lower. Therefore, ice in the drain pipe can be efficiently melted in response to cooling of the precooling chamber.

Furthermore, according to the present invention, a heat sink for heating the drain pipe is provided.
The heating is controlled within a time range that is less than or equal to a predetermined time W based on the number of thermal shocks during the defrosting operation. Therefore, the ice in the drain pipe can be sufficiently melted,
The increase in cooling load on the refrigeration system in the precooling chamber is small.

Further, according to the present invention, the time W for heating the drain pipe heater is set longer as the low temperature exposure temperature of the test chamber or the precooling temperature of the precooling chamber becomes lower. Therefore, the ice in the tube can be efficiently melted in response to the cooling of the precooling chamber.

Embodiment FIG. 1 is a schematic sectional view for explaining the configuration of a thermal shock test apparatus according to an embodiment of the present invention. A test chamber 3 whose periphery is thermally insulated by a heat insulating wall 2 is provided in a housing 1 of the thermal shock test apparatus. A pre-cooling chamber 4 which is also thermally insulated by a heat insulating wall 2 is provided below the test chamber 3 .

A preheating chamber 5, which is also thermally insulated by a heat insulating wall 2, is provided above the test chamber 3.

Inside the precooling chamber 4, an evaporator 6 for cooling the surroundings by evaporation of a refrigerant, and a cooling fan 7 for circulating air within the precooling chamber 4 are provided. The cooling fan 7 is driven by a motor 8 installed outside the precooling chamber. A regenerator 9 is also provided within the precooling chamber 4 . The regenerator 9 has metal fins made of copper, aluminum, or stainless steel, and is cooled by the air circulating in the precooling chamber 4, and absorbs heat when cooling the test chamber 3. In this way, the evaporator 6,
The cooling fan 7 and the regenerator 9 constitute a cooling means 10 for cooling the inside of the precooling chamber 4.

Since the evaporator 6 and the regenerator are cooled to a low temperature, frost tends to form on them. In order to remove this frost, when a defrost operation is performed by introducing hot gas or the like into the evaporator 6, the frost is melted and stored in the drain pan 11 at the lower part of the precooling chamber 4 as drain.

The drain stored in the drain pan 11 also includes that from frost adhering to the wall surface of the precooling chamber 4. If the water level of the drain rises, the volume of the precooling chamber 4 will decrease, and there is a possibility that the water level will reach the evaporator 6 and the regenerator 9 as well. Therefore, the precooling chamber 4 is provided with a drain pipe 12 for draining the drain. The drain pipe 12 is drawn out approximately horizontally to the heat insulating wall 2. The drain pipe 12 is made of synthetic resin, and a heater 13 is provided inside. Heater 1
3, the energization heating state is controlled by the control means 14. The end of the drain pipe 12 is guided below the water level of a drain trap 15 provided outside the heat insulating wall 2. The water level of the drain trap 15 is defined by a drain pipe 16 for draining water to the outside of the housing 1 . In this way, surrounding air and heat are prevented from directly entering the drain pipe 12.

Cool air is circulated within the precooling chamber 4 by a cooling fan 7.

The direction of this cold air is indicated by reference numeral 17.

A cold air outlet 18 is provided between the precooling chamber 4 and the test chamber 3. The cold air outlet 18 is opened and closed by a low temperature tamper 19. A state in which the low temperature damper 19 is angularly displaced and the cold air outlet 18 is opened is shown by a phantom line. In this state, the cold air in the precooling chamber 4 is blown out into the test chamber 3 without circulating in the direction shown by reference numeral 17. The air in the test chamber 3 is transferred to the regenerator 9.
and is cooled by an evaporator 6. By opening the low temperature damper 19 in this manner, the inside of the test chamber 3 can be rapidly cooled.

The preheating chamber 5 is provided with a heater 20 and a heating fan 21 . The heating fan 21 is driven by a motor 22, and hot air circulates within the preheating chamber 5. A hot air outlet 23 is provided between the preheating chamber 5 and the test chamber 3, and is opened and closed by a high temperature damper 24. When the high temperature damper 24 is opened, the hot air in the preheating chamber 5 circulates into the test chamber 3, rapidly heating the inside of the test chamber 3.

The opening of the test chamber 3 is provided with a door 25 that can be opened and closed. The door 25 is opened, the test object is carried into the test chamber 3, and the test object is discharged after the test is completed. Door like this 2
5 and the heat insulating wall 2 are airtightly sealed. However, since the temperature within the test chamber 3 rapidly rises or falls, it is difficult to completely prevent ambient moisture from entering the test chamber 3 through the sealed portion of the door 25.

Depending on the thermal shock test standard, there may be a difference between low and high temperatures.
A process of maintaining it at room temperature is also required. For this purpose, the housing 1 is provided with an intake duct 26 and an exhaust duct 27. An intake port 28 is provided to introduce room temperature air into the test chamber 3 from the intake duct 26. The intake port 28 is opened and closed by an intake damper 29. An intake/fan 30 is provided within the intake duct 26. Reference numeral 31 indicates the direction of air inflow into the intake duct 26.

An exhaust port 32 is provided between the exhaust duct 27 and the test chamber 3, and is opened and closed by an exhaust damper 33. Reference mark 3
4 indicates the direction of air discharge within the exhaust duct 27.

Inside the housing 1, there is further provided a detection means 35 for detecting the point in time when the heater 13 of the drain pipe 12 starts heating based on the number of cold shocks.

FIG. 2 is a schematic block diagram showing the electrical configuration of the thermal shock test apparatus shown in FIG. Detection means 3 shown in the first diagram
5 is a central processing unit (hereinafter referred to as rCPU) realized by a microcomputer or the like.

(abbreviated as ) 36. Furthermore, a read-only memory (hereinafter abbreviated as ROM J) 37 in which programs for the operation of the CP Ll 36 are stored, and a CP
Writable memory (hereinafter abbreviated as "RAMJ") 38 as a work memory necessary for the operation of 036
is provided. Furthermore, the detection circuit 35 includes a CPU 3
A counter 39 controlled by 6 is also provided.

The low temperature exposure temperature Go1 for the thermal shock test is set by the low temperature exposure temperature setting means 40.

This temperature is, for example, -40°C. The precooling temperature setting means 41 responds to the output from the low temperature exposure temperature setting means 40 and sets the precooling temperature T2 shown by the first equation.

T2=T1-ΔT1...(1) When the low temperature exposure temperature T1 is ~40°C, the precooling temperature T2 is
For example, it is set to -50°C.

The high temperature exposure temperature T3 for the thermal shock test is set by the high temperature exposure temperature setting means 42.

This high temperature exposure temperature T3 is, for example, 150°C.

The preheating temperature setting means 43 is the high temperature exposure temperature setting means 42.
In response to the output from the preheating temperature T4, the preheating temperature T4 is set according to the second equation.

T4=T3+ΔT3...(2) The low temperature and high temperature exposure temperatures TI set in this way, and the exposure time to T3 are set, for example, to 30 minutes each.

The time for exposure to normal temperature between high and low temperatures is set to, for example, 5 minutes. The number of times the cycle of low temperature and high temperature thermal shock is repeated is set to, for example, 670 times. In such a thermal shock test, the number of defrosts N, which is the interval between the number of times of thermal shock for performing a defrosting operation, is, for example, 45 times,
Set by.

() The p U 36 controls the cooling means 10 to cool the pre-cooling chamber 4 to the pre-cooling temperature T2 according to the program set in the ROM 37.The CPU 36 controls the heater 20 to cool the pre-cooling chamber 5. The temperature is heated to the preheating temperature T4. Also, the low temperature damper 19, high temperature tamper 24, intake damper 29, intake fan 30 and exhaust tamper 33 are controlled to perform a cycle of thermal shock.The number of cycles is determined by the counter 39.
The cooling means 10 is operated for defrosting every time the number of times N of Tefrost is reached. From this defrosting operation, heating of the heater 13 is started n1 times before the pre-scheduled start count. This advance scheduled start number rn is set by the advance scheduled start number setting means 45. The CPU 36 calculates, from the count value of the counter 39 that counts the number of thermal shock cycles,
When it is detected that the number of times until the defrosting operation starts is less than m, the heater 13 is energized via the control means 14 to heat the drain pipe 12.

FIG. 3 is a diagram for explaining a process in which the thermal shock testing apparatus of the embodiment shown in the first figure performs thermal shock a set number of times. FIG. 3(1) shows the state in which each cycle of thermal shock is performed. FIG. 3(2) shows the state of defrosting operation. For convenience of explanation, it is assumed that the defrosting operation is performed every five times of thermal shock. After the fifth thermal shock,
The cooling means 10 starts the first defrosting operation. After the defrosting operation is completed, the cooling means 10 is again operated for cooling. Pre-cooling chamber 4
When the temperature inside reaches the precooling temperature, the sixth and subsequent thermal shocks are performed. In this way, the thermal shock test is performed a set number of times while performing the defrosting operation every fifth time.

FIG. 3(3) shows a state in which the heater 13 is heated with electricity. The heating of the heater 13 is performed m times in advance of the start of the defrosting operation.

Figure 3 (3) shows the case of m=1 (3), and the heater 13 starts heating at the 4th, 9th, 144th time, etc., and also starts heating at the end of the defrosting operation. finish.

FIG. 4 is a flowchart for explaining the operation shown in the third figure in the thermal shock test apparatus shown in the first figure. From step s1 to step s2 and step s3, the total number of thermal shocks and the number n of defrosting operations are both initialized to 1. Thermal shock shall be performed a total of times, and the defrosting operation shall be performed every N times.

After initialization, the process moves to step s4, where it is determined whether T1 has reached the number N of defrost operation starts, which is a defrosting operation. If n has not reached the number N of defrost operation starts, the process moves to step s5. In step s5, if the number n of thermal shocks has not reached the number N-nl of pre-cooling of the heater 13, the process moves to step 86.

In step s4, when the number of times n of thermal shocks has reached the number N for which defrost operation should be performed, step s
At step 7, a defrost operation, which is a defrosting operation, of the cooling means 1o is performed. Next, in step s8, it is determined whether the defrost operation should be ended. If the process should not end, the process returns to step s7 again. In step s8, when the defrost operation should be ended, step S
9 and step slo. In step s9, power supply to the heater 13 of the drain pipe 12 is stopped.

In step slo, the number of times n for determining whether or not to perform defrost operation is set to 1 again.

In step s5, when it is determined that the number of thermal shocks n is equal to or greater than N-m, the process moves to step all, where the heater 13 of the drain pipe 12 is energized,
Drain pipe 12 is heated.

Since the drain pipe 12 is heated m times before the defrost operation is performed, the water frozen in the drain pipe 12 can be dissolved before the defrost operation is performed.

When each of the above processes is completed, one cycle of thermal shock is performed in step s6. Next, in step S12, it is determined whether the total number of times k has reached the set number of times K and whether or not the thermal shock test should be ended. If the thermal shock test should not be terminated, the process moves to steps s13 and s14, where 1 (and m are each incremented by 1, and the process returns to step S4 again. In step s12, it is determined that the thermal shock test should be terminated. , the process moves to step s15 and ends.

FIG. 5 is a diagram for explaining the operation of another embodiment of the thermal shock testing apparatus according to the present invention. In this embodiment, as shown in FIG. 5(1), the pre-scheduled start number nl is set to be larger as the pre-cooling temperature T2 becomes lower. The setting of the value of the scheduled advance start count m is performed according to the flowchart 1- shown in FIG. 5(2). step p
If T2 is determined to be greater than or equal to 120 in step p2 from l, m is set to O in step p3. If it is determined in step 1)4 that T2 is less than 120 - 30 or more, m is set to 1 in step p5. Thereafter, in the same manner, I
The value of l'l is set. In this way, in step p13, the precooling temperature T2 and the fifth
A value of the number of advance scheduled starts m having a correspondence relationship as shown in FIG. 1 is set. Such pre-cooling temperature T2 is set by the first equation based on the value of low temperature exposure temperature T1. Therefore, it goes without saying that the number of scheduled advance starts m may be set according to the low temperature exposure temperature T1. The value of ΔT1 in the first equation is set in the ROM 37 in advance, and the calculation of the first equation is performed by the CPU 36. The correspondence relationship shown in FIG. 5(1) is also set in the ROM 37 as data. This kind of correspondence relationship, eight T1
The values are determined in advance through experiments.

FIG. 6 is a diagram for explaining the operation when the value of m is 2 in each of the above embodiments.

In FIG. 6(1), a solid line indicates the temperature in the test chamber 3, a broken line indicates the temperature in the pre-cooling chamber 4, and a two-dot chain line indicates the temperature in the pre-heating chamber 5. Temperature TO indicates room temperature, T1 indicates low temperature exposure temperature, T2 indicates precooling temperature, T3 indicates high temperature exposure temperature, and T4 indicates preheating temperature. FIG. 6(2) shows a state in which the heater 13 is energized.

When the number of thermal shock tests reaches the N-2 cycle after the end of the defrost operation every N times, the heater 13 is turned on. Upon completion of the Nth thermal shock cycle, cooling means 1
0 defrost 1~Operation is started. The temperature in the precooling chamber increases during defrost operation. Therefore, even after the defrost operation is finished, a preparation period is required to cool the inside of the precooling chamber 4 until the next thermal shock cycle begins. The heater 13/\ is turned off when the defrost operation is completed.
Be given an F. In this way, since the heater 13 is heated prior to the defrost operation, the ice in the drain pipe is sufficiently melted during the defrost operation.

Therefore, the drain generated during the defrost operation can be sufficiently discharged.

FIG. 7 is a moist air i-X diagram for explaining the reason why a large amount of drainage is generated in the precooling chamber 4.

A does not indicate an indoor state point at 25° C. and 50% relative humidity. At this time, 0.0% per kg of dry air. Contains mkg of water. When the precooling temperature is 150°C, even at state point B on the saturation line 11, there is 1/1 of state point A in the air.
It can only contain 0.00% water. The remaining moisture adheres to the inside of the precooling chamber 4 as frost. According to each of the embodiments described above, it is possible to sufficiently discharge the drain generated by defrosting the frost that has adhered in this way.

In each of the embodiments described above, heating of the heater 13 is started m times before the scheduled start of the thermal shock cycle. Since each thermal shock cycle is performed for a fixed period of time, it goes without saying that the heater 13 may be heated for a period of time W corresponding to the number of times m, prior to the defrost operation. Furthermore, if the heating of the heater 13 is started according to the time W, as shown in FIG. 6(3), 1
Heating of the heater 13 can be started even in the middle of the thermal shock cycle. Therefore, the drain pipe 12
can be sufficiently heated, and the cooling load on the cooling means 10 can be reduced.

According to the present invention as described above, the heater in the drain pipe is
It is heated in advance by a preset number of times from the number of thermal shocks during the defrosting operation. As a result, during defrosting operation,
It becomes possible to drain the I/len through the drain pipe. Since the heater of the drain pipe is heated only during the period preceding the defrosting operation by a preset number of times, it is possible to reduce the increase in the cooling load on the cooling means of the precooling chamber.

Further, according to the present invention, the preset number of times prior to the defrosting operation for heating the heater of the drain pipe is set to be larger as the low temperature exposure temperature of the test chamber or the precooling temperature of the defrosting chamber becomes lower. As a result, the drain pipe can be heated as necessary and sufficient in accordance with the exposure temperature and the pre-cooling temperature, and an increase in cooling load can be reduced.

Further, according to the present invention, the heater of the drain pipe can be heated for a predetermined period of time prior to the defrosting operation. As a result, the drain generated in the precooling chamber during the defrosting operation can be sufficiently drained, and an increase in the cooling load on the cooling means of the precooling chamber can be reduced.

Further, according to the present invention, the time period for heating the drain pipe heater prior to the defrosting operation can be set to be longer as the low-temperature exposure temperature or precooling temperature becomes lower. Thereby, the drain pipe can be efficiently heated in accordance with the temperature in the pre-cooling chamber.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing the configuration of an embodiment of the present invention, FIG. 2 is a block diagram showing the electrical configuration of the embodiment shown in FIG. FIG. 4 is a flowchart for explaining the operation in the embodiment shown in the first figure, and FIG. 5 is a diagram for explaining the operation for setting the advance scheduled start count m in another embodiment of the present invention. FIG. 6 is a diagram for explaining temperature changes and energization of the heater 13 in the embodiment shown in FIG. 1 or 5, and FIG. 7 is a diagram for explaining precooling in the embodiment shown in FIG. 1 or 5. It is a psychrometric diagram for explaining that frost builds up inside the room 4. DESCRIPTION OF SYMBOLS 1...Housing, 2...Insulating wall, 3...Test chamber, 4...Precooling chamber, 5...Preheating chamber, 6...Evaporator, 7
...Cooling fan, 9...Regenerator, 10 Cooling means, 1
DESCRIPTION OF SYMBOLS 1... Drain pan, 12... Drain pipe, 13... Heater, 14... Control means, 18... Cold air outlet, 19...
- Low temperature damper, 20... Heater, 21... Heating fan, 23... Hot air outlet, 24... High temperature damper, 25... Door, 35... Detection means, 36... CPU
, 37...ROM, 38...RAM, 39...Counter, 40...Low temperature exposure temperature setting means, 41...
・Pre-cooling temperature setting means, 42... High temperature exposure temperature setting means, 43... Preheating temperature setting means, 44... Defrost number setting means, 45... Pre-scheduled start number setting means Agent Patent attorney Keiichi Nishikyo Department

Claims (4)

[Claims] (1) A thermal shock test was conducted by alternately supplying cold air from the pre-cooling chamber 4 and hot air from the pre-heating chamber 5 to the test chamber 3.
is provided with a cooling means 10 for cooling the precooling chamber to a precooling temperature lower than the low-temperature exposure temperature of the test chamber 3, and a drain pipe 12 for discharging condensate. The cooling means 10 is
In a thermal shock testing apparatus in which a defrosting operation is performed and a heater 13 is provided in the drain pipe 12, the number of thermal shocks required to reach the number of times the defrosting operation is performed is equal to or less than a preset number m. A thermal shock testing apparatus comprising: a detection means 35 for detecting; and a control means 14 for controlling heating of the heater 13 of the drain pipe 12 in response to the output from the detection means 35. (2) The number of times m preset in the detection means 35
The thermal shock test apparatus according to claim 1, wherein is set to be larger as the low temperature exposure temperature or the precooling temperature becomes lower. (3) A thermal shock test was conducted by alternately supplying cold air from the pre-cooling chamber 4 and hot air from the pre-heating chamber 5 to the test chamber 3.
is provided with a cooling means 10 for cooling the precooling chamber to a precooling temperature lower than the low temperature exposure temperature of the test chamber 3, and a drain pipe 12 for discharging the drain, and the number of thermal shocks is predetermined. In a thermal shock testing device in which a defrosting operation of the cooling means 10 is performed every time the number of times N is reached, and a heater 13 is provided in the drain pipe 12, the thermal shock time until the number of times the defrosting operation is reached is preset. and a control means 14 for controlling the heating of the heater 13 of the drain pipe 12 in response to the output from the detection means 35. Thermal shock test equipment. (4) Time w preset in the detection means 35
The thermal shock test apparatus according to claim 3, wherein is set to be larger as the low temperature exposure temperature or the precooling temperature becomes lower.