JP2603407B2 - Constant temperature and humidity - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a constant temperature used for performing burn-in processing for reliability evaluation and screening of various semiconductor elements and electronic circuits, and for examining heat resistance and moisture resistance of various articles and materials. Regarding the humidity controller.

[0002]

2. Description of the Related Art As a method of obtaining air of a desired temperature and humidity in a thermo-hygrostat, there is known a method of producing saturated air having a predetermined dew point temperature and heating it to obtain air of a desired temperature and humidity. I have. As a method of obtaining saturated air having such a predetermined dew point temperature, a method called contact type, in which water is finely divided by shower means, spray means, centrifugal sprayer, etc., and the predetermined temperature air is increased when the contact area with air is increased. A method of obtaining saturated air having a predetermined dew point temperature through a through hole has been known for a long time.

However, in this method, water droplets may be mixed in the saturated air, so that when the saturated air is heated,
Since the water droplets evaporate, the desired relative humidity cannot be obtained.
If the purity control of water is insufficient, water-soluble impurities solidify during contact evaporation with air, and the powder of the impurities scatters.
A pump that circulates water, means for miniaturizing water, a motor for driving the water, a saturation tank for bringing micronized water into contact with air, an eliminator for removing excess water droplets, etc. are required. There are drawbacks in that the structure is complicated and large, the cost is high, the power consumption is large, and the number of failures is large.

Therefore, in order to solve such a problem,
By passing air appropriately humidified by the humidifying means through a heat exchanger cooled to a temperature lower than the dew point temperature, excess water is removed (dehumidified) and saturated air having a predetermined dew point temperature is produced. A method of obtaining desired temperature and humidity air is also used. In such a temperature / humidity control method, the temperature / humidity control is usually performed based on a temperature detected by a dry / wet bulb thermometer, but in principle, a dew point temperature control method is used. Further, an evaporator of a refrigerator is used as the heat exchanger.

[0005]

However, there is still the following problem in a constant temperature and humidity chamber employing a temperature and humidity control system using such a heat exchanger. Since a refrigerator evaporator is used as a heat exchanger,
A refrigerator is required, which hinders downsizing of the thermo-hygrostat and reduction in manufacturing cost. Due to the operation of the refrigerator, further power saving is difficult. In order to simplify the structure and to facilitate management, the temperature of the air that has passed through the heat exchanger without using a wet-bulb thermometer that requires a wet-bulb wick or wick pan and a water circuit for it is not adopted. Even if it is attempted to control the saturated air temperature based on the detected value and the set dew point temperature, the air temperature that has passed through the heat exchanger differs from place to place, and thus was detected at a certain point. It is difficult to say that the temperature is the average temperature of the whole air that has passed through the heat exchanger, and it is difficult to use such detected temperature for dew point control.

The temperature of the air passing through the heat exchanger varies from place to place because the surface temperature of the heat exchanger varies from place to place. The reason why the temperature difference occurs on the heat exchanger as described above is considered as follows. That is, in the refrigerator, a refrigerant such as Freon is circulated, but the refrigerant has a small heat capacity. In addition, in order to prevent the amount of heat exchange in the high-temperature and high-humidity region from becoming excessive and the refrigerator from being overloaded, the circulation amount of the refrigerant may have to be limited, in which case the refrigerant evaporates in the evaporator. Temperature is low (-
About 20 ° C.). Because of these, evaporation of the refrigerant is already completed in the initial stage of the refrigerant flowing into the evaporator, and uniform evaporation (heat exchange) is not performed over the entire evaporator.

Accordingly, the present invention comprises an air-conditioning room, a test room, and air circulation means for circulating air to both the rooms. The air-conditioning room has a heating means, a heat exchanger for generating saturated air, and a flow of circulating air. Humidification means upstream of the heat exchanger in the direction
A thermo-hygrostat which is provided with bets, as compared with a thermo-hygrostat of a conventional same principle can be provided inexpensively can be miniaturized, and to provide what requires less power consumption.

Further, the present invention provides a method for detecting a temperature of an air passing through a heat exchanger at a certain point even when the temperature of the air passing through the heat exchanger is uniform and detecting the temperature of the air passing through the heat exchanger at a certain point. It can be regarded as the temperature average value of the whole air that has passed through the exchanger. Therefore, in order to simplify the structure and facilitate management, the air temperature after passing through the heat exchanger is replaced with the conventional wet bulb thermometer. It is also an object to provide a thermo-hygrostat capable of directly detecting air temperature and controlling a saturated air dew point temperature for obtaining air having a desired temperature and humidity based on the detected air temperature and the set dew point temperature. And

[0009]

In order to solve the above-mentioned problems, the present inventor focused on a heat pipe. The heat pipe is
A heating medium such as Freon, alcohol, water, etc. is selected according to the operating temperature range, and is sealed in a tube such as a copper tube.
One is used as a heat medium evaporation side (heat absorption side) and the other is used as a heat medium condensation side (heat radiation side) with the vicinity of the center as a boundary.

[0010] Such a heat pipe has an advantage that it is extremely simple in structure, small in size and inexpensive in comparison with a refrigerator, and has the advantage that no electric power is required for its operation. In addition, during the cyclical state change of evaporation of the internal heat medium on the heat absorption side and condensation on the heat release side, latent heat for evaporation and condensation is exchanged, but the temperature of the heat itself does not change. In terms of characteristics, it can be said that there is almost no surface temperature difference over the entire heat pipe. Therefore, if a heat pipe is used as the heat exchanger, the temperature of the air passing through the heat exchanger becomes substantially uniform at each part. Only by detecting the temperature of the air passing through the heat exchanger at a certain point, the detected temperature can be used for the saturated air dew point temperature control.

Further, when the cooling of the heat radiation side is stopped, the condensed change starts and the movement of the heat is stopped. Therefore, the cooling capacity of the heat pipe can be easily controlled by controlling the cooling of the heat pipe on the heat medium condensing side. The present inventor has completed the present invention focusing on such a heat pipe. That is, in order to solve the above-mentioned problems, the present invention includes an air-conditioning room, a test room, and air circulation means for circulating air to both the rooms, and the air-conditioning room has a heating means, a heat exchanger for generating saturated air, Humidifying means upstream of the heat exchanger in the flow direction of circulating air
In a thermo-hygrostat provided with, the heat exchanger is:
The heating medium evaporation side in the air-conditioned room, becomes the heating medium condensation side a heat pipe disposed in the air-conditioning outdoor, heat medium condensation side of the cold
Means for controlling the cooling capacity of the heat exchanger by adjusting
It is intended to provide a thermo-hygrostat which is provided.

[0012] As the heat exchanger cooling capacity control means,
For example, a blower that blows heat to the heat medium condensing side of the heat pipe of the heat exchanger to perform heat exchange as necessary, or further, a blow duct that guides air to the heat medium condensing side and passes it
The cooling of the heat medium condensing side of the heat pipe
Items that can be adjusted by controlling the operation and stop of the blower
Can be

As a specific example of controlling the dew point temperature of the saturated air that has passed through the heat exchanger, the humidifying means may be of a water heating type using an electric heater or the like to control the temperature of the saturated air after passing through the heat exchanger. And a means for detecting the air temperature after passing through the heat exchanger. The adjusting means detects the detected air based on the air temperature detected by the temperature detecting means and the set dew point temperature. It is conceivable to operate one of the cooling capacity control means and the humidifying means of the heat exchanger and stop the other so that the temperature approaches the set dew point temperature.

The heating means for heating the saturated air to obtain the desired temperature / humidity air may be arranged downstream of the heat exchanger, but the air passing through the heat exchanger for controlling the dew point temperature is controlled. When means for detecting the temperature of the air is provided, in order to prevent the temperature detecting means from being affected by the radiant heat from the heating means, the air flowing from the test chamber into the air-conditioned room in two flows. After dividing into a common space, a partition wall is arranged, and the heating means is arranged in a ventilation path between the partition wall and the test chamber, and the heat exchanger is interposed between the partition walls. It is conceivable to dispose it in the ventilation path on the side opposite to the ventilation path.

[0015]

According to the constant temperature / humidifier of the present invention, air is circulated to the air conditioning room and the test room by the air circulating means. The air passes through the heat exchanger to be dehumidified and becomes saturated air, and the saturated air is reheated by the heating means to achieve the desired temperature and humidity, for example, 85 ° C.
85% RH, 40 ° C, 90% RH, 60 ° C, 90% RH
Is obtained and supplied to the test room.

Particularly, a heat pipe is used as the heat exchanger.
Heat exchanger is used.
The temperature of the passing air becomes substantially uniform in each part,
There is a means to control the cooling capacity of the heat exchanger
In this control means, the cooling capacity of the heat exchanger is adjusted,
The minimum heat exchange in the heat exchanger, or
Close to that, the heat exchanger surface temperature and the heat exchange
The difference between the temperature of the air passing through the
Air temperature after passing through the heat exchanger
Therefore, the air temperature after passing through the heat exchanger is detected at one point.
The detected temperature is used for saturated air dew point temperature control,
The target temperature and humidity can be accurately obtained.

The humidifying means is of a water heating type, and comprises dew point temperature adjusting means for controlling the saturated air temperature after passing through the heat exchanger, and means for detecting the air temperature after passing through the heat exchanger. When, the adjusting means, based on the air temperature and the set dew point temperature detected by the temperature detecting means, so that the detected air temperature toward the set dew point temperature,
One of the heat exchanger cooling capacity control means and the humidification means is operated and the other is stopped, whereby the temperature of the air passing through the heat exchanger is controlled to the set dew point temperature to obtain the desired temperature and humidity air. It can be so.

In the air-conditioned room, a partition for dividing the air flowing from the test chamber into two flows and then leading the flow to one common space is arranged, and the heating means is connected between the partition and the test chamber. When the heat exchanger is disposed in the ventilation path opposite to the ventilation path with the partition wall interposed therebetween, the air flowing from the test chamber into the air-conditioning chamber is disposed in the ventilation path between the partition walls. Are divided into two streams, one of which is heated by passing through a heating means, and the other is passed through a humidifying means and a heat exchanger, thereby becoming saturated air having a predetermined dew point temperature, and the two are again one common It mixes in the space and becomes the air of the target temperature and humidity and is supplied to the test room. The means for detecting the temperature of the air that has passed through the heat exchanger for controlling the dew point temperature can be installed in the ventilation path of the heat exchanger, which is not affected by the radiant heat from the heating means.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. The thermo-hygrostat includes an air-conditioning room 1 and a test room 2, and substantially all of these rooms are surrounded by a heat insulating wall 3. An opening 21 is provided on the front side of the test chamber 2, and the opening 21 is opened and closed by a heat insulating door (not shown). Further, an air duct 4 is formed along the outer wall 11 of the air conditioning room 1.

The air conditioning room 1 and the test room 2 are partitioned by a partition wall 5, and a partition wall 12 is arranged in a part of the inside of the air conditioning room 1. An electric heater 6 for heating air is disposed in a ventilation path 13 between the partition wall 12 and the partition wall 5 in the air conditioning room 1, and a ventilation path 14 between the partition wall 12 and the air conditioning room outer wall 11.
Is provided with a heat exchanger 7.

The heat exchanger 7 is formed by fixing a plurality of heat pipes 72 through a plurality of heat exchange fins 71.
The heat pipes are arranged, for example, three vertically and eight horizontally. Each heat pipe is formed by sealing a heat medium (for example, alcohol) in a copper tube. The heat medium evaporation side portion is disposed in the ventilation path 14, and the heat medium condensation side portion is disposed in the duct 4. I have. The heat medium condensing side portion is located higher than the heat medium evaporating side portion.

By adopting the heat exchanger 7 composed of such a heat pipe, the structure of the thermo-hygrostat can be simplified, miniaturized and provided at a low cost, and power for operation can be saved. The lower ends of the ventilation passages 13 and 14 in the air-conditioning room 1 face a common space 15, which communicates with the test room 2 through an air inlet from the test room 2.

A humidifier 8 is provided below the heat exchanger 7 and contains water W. The water W is heated by an electric heater 81 to evaporate and humidify the incoming air. Above the heat exchanger 7, a temperature detection sensor S1 is disposed in the ventilation path 14, and this sensor is
The temperature of the air immediately after passing through can be detected. The sensor is not affected by radiant heat from the heater 6 by the partition wall 12.

The upper ends of the air passages 13 and 14 are provided in a common space 1.
6, where a fan F1 for air circulation is provided. The fan F1 is driven by the motor M1. A register (rectifier) R is disposed at an air discharge portion from the fan F1, and a temperature detection sensor S2 is disposed at a position facing the air outlet of the register R. A blower F2 is provided at the lower end of the duct 4 along the air conditioning room to ventilate and cool the heat medium condensing side portion of the heat exchanger heat pipe.
Is provided. The blower F2 is driven by a motor M2.

The air inflow portion at the upper end and the air outflow portion at the lower end of the test chamber 2 regulate the air flow, and prevent the operator's hand or arm from being inserted or prevent the articles from falling. A plate 22 made of a perforated plate, a steel plate, a lattice plate, or the like is provided. An air jacket 24 is formed along substantially the entire inner wall 23 of the test chamber 2 on the outside thereof, and an electric heater 25 for heating the air in the jacket and a fan for stirring and circulating the air in the jacket are partially provided in the jacket. F3
Is provided. The fan F3 is driven by a motor M3.

The temperature detected by the temperature sensor S1 is input to a dew point temperature controller 91. Also,
In the controller 91, a saturated air having a dew point temperature required for obtaining a desired temperature and humidity air can be generated.
The dew point temperature for that can be set. The controller 91 further compares the temperature detected by the sensor S1 with the set dew point temperature, and when the detected temperature becomes lower than the set dew point temperature, the blower F
While the second motor M2 is stopped, the humidifier heater 81 is energized, and when the detected temperature becomes higher than the set dew point temperature, the blower F2 is instructed to rotate while the energization to the humidifier heater 81 is stopped. It has become.

The heater 25 in the air jacket 24 of the test chamber 2 is turned on and off in synchronization with turning on and off the humidifier heater 81. This is to prevent dew condensation on the test chamber wall 23 and to keep the temperature in the test chamber. The dew condensation on the inner wall 23 is closely related to the dew point temperature of the air circulating in the test chamber, and the dew point temperature is proportional to the energization ratio to the humidifier heater 81. Therefore, they are turned on and off synchronously in this manner. Further, the heaters 81 and 25 are provided so that the purpose of preventing dew condensation on the test chamber wall 23 and keeping the temperature in the test chamber can be achieved, and the humidifier 8 can perform necessary humidification.
Has been selected.

The temperature detected by the temperature detection sensor S2 is input to the air temperature controller 92.
In the temperature controller 92, a target air temperature can be set. The controller 92 further includes a sensor S2
Is compared with a set temperature, and based on the difference, the heater 6 is turned on and off so as to obtain a target air temperature.

The fan motors M1 and M3 are constantly operated. In the figure, PW is a power source, I is an inverter, T1, T
2. T3 is a thyristor. In addition to the thyristor, a solid state relay or the like can be used. According to the constant temperature and humidity chamber described above, the air is circulated to the air conditioning room 1 and the test room 2 by the operation of the fan F1.

The air flowing from the test room 2 into the air-conditioning room 1 is divided into two flows passing through the ventilation paths 13 and 14, and the air passing through the ventilation path 13 is heated by the heater 6. The heater 6 is turned on and off based on an instruction from the temperature controller 92. More specifically, the input from the sensor S2 is compared with the set air temperature in the controller 92, and the energization is controlled in proportion to the deviation of the temperature detected by the sensor S2 from the set temperature.

On the other hand, the air passing through the ventilation passage 14 passes through the humidifier 8 in the preceding stage, is appropriately humidified, and then passes through the heat exchanger 7, where it is cooled and dehumidified and becomes saturated air. . Since the heat exchanger 7 includes the heat pipe 72, the temperature of the air that has passed through the heat exchanger 7 is substantially uniform in each part. Therefore, the air temperature detected by one sensor S1 indicates the average temperature of the whole air that has passed through the heat exchanger 7.

The temperature detected by the sensor S1 is determined by the dew point temperature controller 9
1 and the detected temperature is compared with the set dew point temperature. If the detected temperature is higher than the set dew point temperature,
While the power supply to the humidifier heater 81 is stopped, the blower F2
Is operated, thus cooling the heat medium condensing side portion of the heat exchanger heat pipe 72 by ventilation, thereby increasing the cooling capacity of the heat exchanger 7 and consequently the dew point of the saturated air passing through the heat exchanger 7 The temperature drops.

When the detected temperature becomes lower than the set temperature, the humidifier heater 81 is energized while the blower F2 is stopped, and thus the dew point of the saturated air passing through the heat exchanger 7 increases. The heater 81 and the blower F2
Are performed in proportion to the deviation of the detected temperature from the set temperature.

Thus, the temperature of the saturated air that has passed through the heat exchanger 7 is controlled to the set dew point temperature for obtaining air having the desired temperature and humidity. As described above, as a result of controlling the cooling capacity of the heat exchanger 7, the amount of heat exchange in the heat exchanger 7 becomes minimum or close to a necessary minimum, and therefore, the heat exchange surface temperature and the heat exchange amount have passed through the heat exchanger 7. The difference from the air temperature is reduced, and the temperature of the passing air is made uniform in each part, which contributes to more accurate dew point temperature control.

Thus, the heated air flowing out of the ventilation path 13 and the saturated air flowing out of the ventilation path 14 are mixed and stirred by the fan F1 to obtain the desired temperature,
The air is supplied to the test chamber 2 as air having a relative humidity, and an article (not shown) arranged in the test chamber 2 is subjected to a burn-in process or the like. Further, the ventilation path 13 is provided in the air-conditioning chamber 1 so that the heat in the test chamber can flow into the test chamber and be used for reheating the saturated air. The permissible heat value of the inner article can be increased.

In the test chamber 2, the heater 25 of the air jacket 24 is turned on and off in synchronization with the turning on and off of the humidifier heater 81, whereby even if the dew point temperature is changed, the air temperature in the jacket, and hence the air temperature in the jacket, , Test chamber wall 23
Is slightly higher than the dew point temperature of the test chamber air (5 ° C in this example).
高温 15 ° C.).
Of the heat from the outside, the dew condensation on the inner surface of the test chamber wall 23 is prevented, and thus the temperature and humidity accuracy of the test chamber air is improved. Further, since the occurrence of dew condensation is prevented, the problem that occurs when dew condensation occurs is also solved.

The air blown into the test chamber 2 is circulated again to the air-conditioning chamber 1, but the test chamber 2 is surrounded by the heat insulation jacket 24 as described above, and the inner wall 23 is kept at a temperature higher than the dew point temperature. No loss of water vapor due to water, has the same absolute humidity as air in the dew point state, and changes the absolute humidity after mixing even if the air obtained by the heater 6 is combined with the saturated air obtained by the heat exchanger 7 side There is no.

[0038]

According to the present invention as described in the foregoing, the air conditioning chamber, an air circulation means for circulating the air in the test chamber and both said chambers, said air conditioning chamber, a heating means, saturated air generating heat It is a thermo-hygrostat provided with an exchanger and humidifying means on the upstream side of the heat exchanger in the flow direction of the circulating air, and can be downsized compared to a conventional thermo-hygrostat of the same principle. A device that can be provided at low cost and consumes less power can be provided.

Further, according to the present invention, even when the temperature of the air passing through the heat exchanger is uniform at each part and the temperature of the air passing through the heat exchanger is detected at a certain point, the detected air temperature is It can be regarded as the temperature average value of the whole air that has passed through the heat exchanger. Therefore, in order to simplify the structure and facilitate management, the air after passing through the heat exchanger is replaced with the conventional wet bulb thermometer. It is possible to provide a thermo-hygrostat capable of directly detecting a temperature and performing a saturated air dew point temperature control for obtaining air having a target temperature and humidity based on the detected air temperature and a set dew point temperature. it can.

In particular, by controlling the cooling capacity of the heat exchanger by means for controlling the cooling capacity of the heat exchanger, the amount of heat exchange in the heat exchanger is reduced to a necessary minimum or close to that required. a vessel surface temperature, to reduce the difference between the temperature of air passing through the heat exchanger, thereby further, since the air temperature after the heat exchanger passes through can be made uniform among the respective units, the heat exchange
Based on the detected temperature of air after passing through the exchanger and the set dew point temperature
The saturated air dew point temperature control becomes more accurate.

According to the thermo-hygrostat of the second aspect, the temperature of the air passing through the heat exchanger is controlled to the set dew point temperature, and the desired temperature and humidity air can be obtained .

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air-conditioning room 11 Outside wall of an air-conditioning room 12 Partition wall of an air-conditioning room 13, 14 Airway 15 Common space below an airway 16 Common space above an airway 2 Test room 21 Test room opening 22 Plate body for rectification etc. 23 Test room Wall 24 Air jacket 25 Inner jacket heater 3 Insulation wall 4 Air duct 5 Partition wall 6 Air heater 7 Heat exchanger 71 Fin 72 Heat pipe 8 Humidifier 81 Humidifier heater 91 Dew point temperature controller 92 Air temperature controller F1 Air circulation Fan F2 Blower F3 Fan S1, S2 Temperature detection sensor

Claims (2)

(57) [Claims] 1. An air-conditioning room, a test room, and air circulation means for circulating air to both the rooms, wherein the air-conditioning room has heating means
A heat exchanger for generating saturated air, and humidifying means upstream of the heat exchanger in the flow direction of the circulating air.
That in a thermo-hygrostat, the heat exchanger, the heating medium evaporation side to the air-conditioned room, becomes the heating medium condensation side a heat pipe disposed in the air-conditioning outdoor, and adjusting the cooling of the heat medium condensation side
A thermo-hygrostat, comprising: means for controlling a cooling capacity of the heat exchanger . 2. The humidifying means is of a water heating type,
Dew for controlling the saturated air temperature after passing through the heat exchanger
The temperature of the air after passing through the point temperature control means and the heat exchanger is detected.
And the dew point temperature adjusting means includes
The air temperature detected by the temperature detection means and the set dew point temperature
The detected air temperature goes to the set dew point temperature
The heat exchanger cooling capacity control means and the humidifier
Activate one of the stages and stop the other
The thermo-hygrostat according to claim 1, wherein the thermo-humidifier is configured as follows .