JPH0743311B2 - Constant temperature / constant humidity tester - Google Patents

Description

TECHNICAL FIELD The present invention relates to a constant temperature / constant humidity test apparatus.

[Prior Art] Conventionally, a device under test, such as a substrate that constitutes an electronic circuit, is housed in a housing chamber, and this chamber is maintained and controlled at a predetermined temperature and humidity condition for a predetermined time to obtain various properties of the device under test. Conventionally, a constant temperature / constant humidity test device for measuring changes in characteristics has been widely used. In this case, an electric heater is mainly used for the former and a humidifying water tank containing an electric heater is often used for the latter as a device for maintaining a predetermined temperature and humidity higher than the outside air temperature in the accommodation chamber. Further, in order to maintain a low temperature and a low humidity, which are lower than the outside air temperature, it is common to incorporate a refrigerating machine into the accommodation chamber.

[Problems to be Solved by the Invention] However, the object to be tested is not limited to the one under the severe conditions in which the temperature is lowered to a negative temperature of less than 0 ° C., for example, room temperature + 10 ° C. to 85 ° C. Refrigeration equipment is not always necessary for the test object to be tested within the range of ° C.

Incorporation of a refrigerating machine has many disadvantages such as high cost, complicated apparatus as a whole, and increased operating and maintenance costs and maintenance costs. For this reason, for example, some devices omit the refrigeration equipment. This utilizes a motor cooling fan that cools the motor of the stirring fan for uniformizing the atmosphere in the storage chamber.

That is, a motor main body cooling fan is attached to the rear shaft of a stirring fan drive motor disposed in the rear of the storage chamber, the cooling fan is made large, and a part of the blown air volume is part of the rear wall of the storage chamber. It is what is blown directly onto the surface as cooling air.

Therefore, when the outside of the wall surface is cooled, a temperature difference occurs between the inside and outside, dew condensation occurs inside the wall surface, and part of the water in the air inside the accommodation room is condensed and separated, which results in the temperature inside the accommodation room. It is possible to control.

However, in the above means, the stirring fan and the cooling fan always have the same rotation speed, which causes a new problem.

That is, the stirring fan, which controls the rotation according to the temperature / humidity conditions in the storage chamber, rotates at a low speed when the temperature or humidity in the storage chamber enters a stable region in which power is consumed. It is very preferable in terms of. On the other hand,
When the stirring fan is controlled to the low speed side, the cooling fan also rotates at a low speed, the cooling effect for dew condensation is lowered, and the humidity condition during the test may be changed.

In order to avoid this, it is necessary to rotate each fan at a high speed and increase the amount of electricity supplied to the heater, resulting in a large amount of waste of the amount of electric power for operation and maintenance.

Therefore, an object of the present invention is to provide a constant temperature / constant humidity test apparatus suitable for tests in the range of normal temperature (room temperature + 10 ° C.) to high temperature and high humidity and requiring less operation and maintenance power consumption. .

[Means for Solving the Problem] In order to achieve the above-mentioned object, the present invention provides a storage chamber with a door for storing a device under test, a cooling passage having a wall surface of the storage chamber as a cooling surface, and a control unit. A temperature raising heater for the storage chamber, which is controlled based on a signal from the storage chamber, and a humidifying device for the storage chamber,
It is provided with a stirring device for uniformizing the atmosphere in the storage chamber, and an ON / OFF fan forcibly sending cooling air taken in from the outside into the cooling passage.

[Operation of the Invention] Therefore, according to the constant temperature / constant humidity test apparatus of the present invention, when the apparatus is set to high temperature and high humidity, the cooling fan is OF
When the temperature becomes F, the temperature raising heater, the humidifying device, and the stirring device enter the operating state, so that the high temperature can be quickly increased from room temperature.
High humidity is reached and high temperature and humidity tests can be performed. When the temperature / humidity enters the stable range, the heater energization operation becomes longer, and the intermittent energization operation starts. Therefore, in combination with the fan off condition, the operation maintenance power consumption can be reduced.

Next, if the humidity that can be input for the temperature is set in the room temperature range, the fan is turned on, and the cooling air flows through the cooling passage to cool the cooling surface. Dew condensation due to the temperature difference accelerates dehumidification, and a predetermined temperature and humidity can be quickly obtained.

[Embodiment] An embodiment of the present invention will be described in detail below with reference to Figs.

In order to accommodate various types of DUTs 1, a rectangular parallelepiped accommodating chamber 5 having a door 3 on the entire surface side is provided. Above and below the accommodation chamber 5,
The left and right four-sided wall has a structure surrounded by a heat insulating material 7 and an exterior plate 9 also serving as an outer wall. The front side of the storage chamber 5 (first
The door 3 is attached to the left side of the drawing so as to be rotatable and openable. In this case, the door 3 is a thick rectangular plate as shown in the figure,
Left and right pins 11 near the bottom are provided. Then, it is pivotally supported by left and right brackets 13 on the lower side of the exterior plate 9 on both sides of the accommodation chamber 5. Both front and back surfaces of the door 3 are made of steel plate, and a heat insulating material 17 is filled in the middle. An inner plate 19 made of glass fiber reinforced epoxy resin is further formed in a butt-shaped cross section with a flange and attached to the rear surface of the door 3, that is, the surface in contact with the accommodation chamber 5 side.

The rear wall plate 21 (the wall plate on the right side in FIG. 1) in the accommodation chamber 5 is made of a steel plate, but is used as a cooling surface of a cooling passage 43 described later without applying a heat insulating material layer as shown in the drawing. This rear wall 21
An electric heater 23 as a heater for raising the temperature of the storage chamber 5 is disposed horizontally in the vicinity of the center on the storage chamber side. A part of the lower position of the electric heater 23 in the accommodation chamber 5 is formed to be low, and a humidifying device 25 is provided therein. Humidifier 25
Is composed of a humidifying water tank 27 having a built-in electric heater for raising the temperature, not shown.

Above the electric heater 23, a stirring device 29 for equalizing the atmosphere in the storage chamber 5 is arranged. The stirring device 29 is a motor
31, long shaft 33, propeller 35 attached to the tip,
The first partition wall 37 is vertically arranged between the periphery of the propeller 35 and the inner wall of the accommodation chamber 5. A gap is secured between the lower edge of the first partition wall 37 and the humidifying water tank 27 to form a stirring airflow passage. On the rear part of the motor 31, a propeller 39 for cooling the motor body is mounted.

A second partition plate 41 is vertically arranged substantially parallel to the rear wall surface 21 of the accommodation chamber 5 (right side in FIG. 1) with a slight gap. And these, the rear wall surface 21 and the second
A gap with the partition plate 41 forms a cooling passage 43. The periphery of the second partition plate 41 (on the right side in FIG. 1) and the periphery of the cooling passage 43 are surrounded by a steel plate case 45 as shown in the figure. An on / off fan 47 for introducing cooling air from the outside into 43 is independently provided.

In this case, the fan 47 is an axial flow fan, and external air serving as cooling air is sucked from a large number of holes 49 provided on both side surfaces near the intermediate height of the case 45. Then, the forced cooling device 53 is configured so that the air that has passed through the cooling passage 43 and cooled the rear wall surface 21 is discharged from a large number of holes 51 provided on both upper side surfaces of the case 45.

In the case of this embodiment, a parallel fin type heat sink 55 is mounted near the lower part of the rear wall surface 21 so as to penetrate the wall surface,
Although the amount of heat dissipated between the wall surfaces is increased, it goes without saying that the heat sink 55 may be a heat pipe or the like.

A water supply tank 57 for the humidifying water tank 27 is arranged above the agitator motor 31 which is the upper part of the case 45. A drainage tank 59 for receiving drainage from the humidifying water tank 27 is provided near the bottom of the case 45.

On the other hand, in the accommodation chamber 5, there are provided leg members 61 on both left and right sides, and a shelf plate 65 whose upper surface portion 63 is horizontal is arranged so that it can be taken in and out of the accommodation chamber 5. The shelf board 65 is made of glass fiber reinforced epoxy resin and is provided with a large number of holes for vertical ventilation.

At the time of opening the front door 3, the upper edge thereof pivots to the front side (left side in FIG. 1) and falls down as shown by the dotted line in FIG. 1,
The upper surface of the interior plate 19, which is the rear surface of the door 3, that is, the surface facing the inside of the storage chamber 5, is horizontally held after rotating toward the front. For this purpose, hinged arms 67 are attached to both upper sides of the exterior plate 9 of the accommodation chamber 5. The left and right arms 67 move the door 3 to the exterior plate 9 of the accommodation chamber 5 only when the door 3 is released.
Suspend diagonally from both sides above and hold horizontally.
When the door 3 is closed, the arms 67 are configured to be folded near the outer sides of both side edges of the door 3.

Water is supplied from the water supply tank 57 to the humidifying water tank 27 by controlling an electromagnetic valve (not shown) provided in the middle of a connecting pipe (not shown) with a float switch (not shown). The surface of the humidifying water tank 27 is now
It is maintained at a predetermined level. Further, in order to prevent overflow of the humidifying water tank 27 due to troubles such as the solenoid valve and the float switch, an overflow pipe line (not shown) is provided from the float chamber containing the float switch (not shown) to the drain tank 59. Has been done.

Further, for discharging the water from the humidifying water tank 27 and the drainage tank 59, discharging the water from the float chamber (not shown), and discharging the condensed condensed water from the bottom surface 69 in the storage chamber 5, the bottom exterior plate of the storage chamber 5 is discharged. A drainage pipe 71 is provided below 9.

The drainage pipe 71 is connected to the relay socket 79 provided with the discharge ports 73, 75, 77, etc. at the above-mentioned locations in the vicinity of the center of the storage chamber bottom exterior plate 9. A plurality of rubber hoses 81 are connected to the relay socket 79 as flexible conduits, and the other end of the hose 81 can be pulled out toward the lower front side of the door 3 to hang it down. As a result, drainage to the outside is performed as necessary.

Specifically, an elongated recess 85 is provided on the front wall surface 83, which is a part of the outer wall of the storage chamber 5 near the bottom of the door 3. An elongated through hole 89 is formed in a vertical bottom surface 87 of the recess 85, and a bracket 91 for detachably fixing the other end of the hose is provided therein. In the case of this embodiment, the bracket 91 is attached and detached by attaching a magnet chuck (not shown) to the bracket 91. The bracket 91 for the hose should be
81 An insertion sleeve 95 is attached. The hose 81 is inserted around the inner periphery of the sleeve 95 on the inner side and fixed with a band. Then, the rubber plug 97 is fitted into the other end of the sleeve 95, that is, the front end to open and close each hose 81. The cover that covers the entire surface of the recess 85 may be fixed with screws to improve the appearance and prevent erroneous operation. In addition, each hose 81 has a length, that is, a slack, so that it can be pulled out from the recess 85 toward the outside and hang down.

The accommodating chamber 5 and other devices configured as described above, the electric heater 23, the humidifying device 25, the stirring device 29, and the forced cooling device 5
For each of the 3 etc., a control unit 99 for controlling them is provided. The control unit 99 is arranged below the accommodation chamber 5 as shown in FIG. 1, and includes a temperature sensor, a humidity sensor, etc. (not shown) provided in each of the devices corresponding to the set temperature and humidity conditions. Each device is controlled by a built-in timer (not shown) for a predetermined time.

The constant temperature / constant humidity test device of this embodiment configured as described above operates as follows due to the presence of the forced cooling device 53.

In Fig. 3, the horizontal axis represents the temperature T ° C of the accommodation room, and the vertical axis represents the same relative humidity value.
The figure shows the RH%. That is, in the OFF region where the fan 47 of the forced cooling device 53 is not operated, the temperature and humidity can be controlled within the range A in the figure. This is a constant temperature and high humidity range, and it is shown that the operation control of the electric heater 23, the humidifying device 25, the stirring device 29, and the like can be maintained under the conditions within this range.

Next, in the ON region in which the fan 47 is operated, when the forced cooling device 53 is operated, the cooling air flows in the cooling passage 43, so that the control in the range B shown by hatching in FIG. Is possible. In other words, the control range is extended to the low temperature region where the temperature is constant. This is because the operation of the fan 47 causes the rear wall plate 21 to be forcibly cooled by the cooling air from the outside air, so that dew condensation and dehumidification are promoted with respect to the atmosphere in the storage chamber 5.

In this case, in the OFF region where the fan 47 is stopped, the electric heater 23, the humidifying device 25, and the agitating device 29 are operated, so that power can be saved by turning off the fan 47. This is because if the fan 47 continues to operate in high temperature and humidity areas,
This is because the electric heater 23 and the built-in heater of the humidifying device 25 must continue to be energized because the temperature inside the storage chamber 5 is lowered too much. Therefore, while the fan 47 is stopped in the above area, the OFF operation time of the electric heater 25 becomes longer and the intermittent energization operation is performed, so that the total operation power consumption is reduced.

The relationship between the control region and the maintenance power depending on the ON / OFF of the fan 47 is shown in another chart as shown in FIGS. 4 and 5. That is, as shown in FIG. 4, the horizontal axis shows the dry bulb humidity T.
In this chart with C and the relative humidity RH% on the vertical axis, when the rotation of the fan 47 is ON, the range of the shaded C zone in the figure can be controlled. Even if the rotation of the fan 47 is turned off, the range of the hatched D zone in the figure can be controlled. In other words, the cooling can be weakened in the constant temperature and high humidity range.

Furthermore, the required maintenance power of the device can be saved as described above by turning the fan 47 on and off, and this state is shown in the chart of FIG. In this chart, the horizontal axis shows temperature T ° C and relative humidity RH%,
The vertical axis shows the maintenance power Q cal. When maintaining the conditions of the maximum controlled humidity T max and the maximum controlled humidity RH max of this device, the maintenance power may be Q ₁ in the device of the embodiment. That is, as described above, since the fan 47 can be stopped at any time in this region, each heater can be energized intermittently as shown by the thick solid line in the figure. This allows the maintenance power to be as low as Q ₁ .

On the other hand, in the conventional device, the cooling fan cannot be arbitrarily stopped as described above, and therefore each heater must be continued. As a result, the maintenance power rises as shown by the dotted line in the figure, and the maximum value Q ₂ is significantly increased.

[Effects of the Invention] As is apparent from the above, according to the configuration of the present invention, the test object to be tested within the range of normal temperature (room temperature + 10 ° C) to high temperature and humidity can be tested without any problem. In addition to being able to perform the above, it does not require refrigeration equipment, which is very preferable in terms of cost. Moreover, since the fan can be turned on and off independently, stable temperature and humidity in the storage chamber can be obtained. Moreover, there is an advantage that the amount of operating power consumption can be reduced.

[Brief description of drawings]

FIG. 1 is a side view including a partial cross section showing an embodiment of a constant temperature / constant humidity test apparatus according to the present invention, FIG. 2 is its front view, FIG. 3, FIG. 4 and FIG. FIG. 6 is an operation characteristic diagram of Description of main drawing symbols 1 ... DUT 3 ... Door 5 ... Storage room 21 ... Rear wall plate (partial wall surface) 23 ... Electric heater (heater for heating) 25 ... Humidification device 29 ... Uniform atmosphere in storage room Stirrer 43 ... Cooling passage 47 ... Fan 99 ... Controller

Claims (1)

[Claims] 1. A storage chamber with a door for storing a device under test, a cooling passage having a wall surface of the storage chamber as a cooling surface, and a heater for raising the temperature in the storage chamber controlled based on a signal from a control unit. A humidifying device for the storage chamber, a stirring device for equalizing the atmosphere in the storage chamber, and a fan that can be turned on / off to forcibly send the cooling air taken from the outside to the cooling passage. A constant temperature / humidity test device.