JPH0334575Y2 - - Google Patents

Description

[Detailed explanation of the invention] Industrial field of application This invention can be used in factories with large volumes, etc.
This invention relates to a cooling device that uses a package air conditioner to cool a specific part of a room.

Conventional technology In various factories, the ambient temperature inside the factory becomes high in the summer, creating a poor working environment and lowering the work efficiency of workers. It's on. In this case, since the factory has a large volume and many heat generating elements, a large cooling device is required to cool the entire factory, resulting in high equipment costs and running costs. Therefore, conventionally, only a specific part of a factory, for example, a work area where workers work, is cooled.

Conventionally, in order to perform partial cooling, for example, as shown in Fig. 4, a single casing is equipped with refrigerant cycle equipment such as a compressor 2, condenser 3, and evaporator 1, a blower, an air filter, an automatic control mechanism, etc. A cooling device (package air conditioner) 5 built into the air conditioner 4 is installed in a cooling section of the factory, and the condenser 3 is connected to a cooling tower 6 and a cooling water pump 7 provided in the factory.
Then, the cooling water pump 7 circulates the cooling medium, and air is introduced into the air conditioner 5 to generate cold air inside.
The cold air is blown towards the worker.

Since the cooling device is mass-produced, it has the advantage that it is smaller and cheaper than purchasing and assembling each component individually, and is easier to install and handle. However, since the package air conditioner 5 is manufactured primarily for indoor cooling, it usually performs cooling while circulating indoor air. Therefore, if the temperature condition of the air introduced into the air conditioner 5 is set low, that is, below about 25° C. WB, and air with a temperature higher than that is introduced, the protection device will work and the device will become inoperable.

Incidentally, inside a factory, the air is often dirty with dust, oil smoke, etc., and the temperature is often higher than the outside temperature because there are many heating elements. Therefore,
In the cooling device, outside air is introduced into the air conditioner 5 without introducing air inside the factory. However, there is a problem in the summer when the outside temperature rises above 25°C WB, making it impossible to operate.

Therefore, in order to improve the above-mentioned problem, as shown in FIG. A part of the cold air (approximately 20% of the total air volume) is returned to the outside air introduction duct 8, where the outside air and cold air are mixed to introduce outside air lower than 25°C WB into the air conditioner 5. .

Problems to be Solved by the Invention With the above-described configuration, low temperature outside air is introduced into the air conditioner 1, so that no operational failure occurs. However, since the amount of air blown from the air duct 9 decreases and the cooling capacity decreases, there is a problem that a large-sized cooling device is required. Furthermore, since the temperature of the cold air in large air-conditioning equipment is low, there is a problem that if the cold air is applied directly to the worker, the worker may become too cold.

Means to Solve the Problems This invention has a package air conditioner that has refrigerant cycle equipment such as a compressor, condenser, and evaporator, as well as a blower, air filter, automatic control mechanism, etc. built into the casing, and uses outside air for package air conditioning. In an air conditioner that is introduced into an aircraft, turns into cold air internally, and blows this cold air into the cabin, a return duct is branched from a part of the air duct that blows out the cold air of the package air conditioner, and the return duct is connected to the air conditioner. A bypass duct is connected to the outside air introduction duct of the package air conditioner, a bypass duct is branched on the upstream side of the return duct of the outside air introduction duct, and the bypass duct is communicated to the upstream side of the blower of the package air conditioner.

Function This idea supplies a part of the air blown from the blower of the package air conditioner through the air duct to the outside air introduction duct via the return duct, and converts the outside air and cold air on the upstream side of the evaporator of the package air conditioner. The air is mixed and introduced into the evaporator at a temperature below 25°C WB, and at the same time, a part of the outside air is supplied from the outside air introduction duct upstream of the return duct to the upstream side of the blower of the package air conditioner, and the outside air and the evaporator are mixed by the blower. The air is mixed with the cold air generated by the air and is blown into the room from the air duct.

Embodiment FIG. 1 is a drawing showing an embodiment of the present invention. In the figure, 15 is a package air conditioner, and a casing 16 includes refrigerant cycle system equipment such as an evaporator 17 and a compressor and condenser (not shown). A blower 18, an air filter (not shown), an automatic control mechanism, etc. are incorporated. Reference numeral 19 denotes an outside air introduction duct that introduces outside air to the upstream side of the evaporator 17. Reference numeral 20 denotes a blower duct that guides the cold air generated by the evaporator 17 and blown out by the blower 18 into the room. 21 is a return duct branched from the ventilation duct 20, which is communicated with the outside air introduction duct 19, and is connected to the ventilation duct 2.
A part of the cold air inside 0 is returned to the outside air introduction duct 19,
Outside air and cold air are mixed on the upstream side of the evaporator 17. 22 is a bypass duct branched from the upstream side of the return duct 21 of the outside air introduction duct 19, and is communicated with the upstream side of the blower 18 of the package air conditioner 15, and a part of the outside air in the outside air introduction duct 19 is transferred to the blower. Supply to 18. A first damper 23 is provided between the return duct 21 and the bypass duct 22 in the outside air introduction duct 19, and opens and closes the outside air introduction duct 19. A second damper 24 is provided in the return duct 21 and opens and closes the return duct 21. 25 is bypass duct 22
The third damper installed inside the bypass duct 22
Open and close. Note that the first damper 23 and the second
The damper 24 and the third damper 25 are configured so that they can be automatically opened and closed from the outside by appropriate means. A temperature sensor 26 is provided near the open end of the outside air introduction duct 19, and measures the temperature of the outside air introduced, and transmits it to the control circuit.

The cooling device having the above structure has a first damper 2 during operation.
3, the second damper 24, and the third damper 25 are opened at predetermined opening degrees, and the package air conditioner 1 is opened.
Activate 5. Then, outside air is introduced from the outside air introduction duct 19, and the introduced outside air is guided to the upstream side of the evaporator 17 of the package air conditioner 15, and is converted into cold air by the evaporator 17. The cold air is then blown out from the package air conditioner 15 by the blower 18 and blown out to the work area in the factory through the air duct 20 for cooling. During this cooling, a part of the cold air blown is returned from the blower duct 20 to the outside air introduction duct 19 via the return duct 21, mixed with outside air upstream of the evaporator 17, and the temperature of the outside air is lowered to stop the operation of the air conditioner 17. At the same time, a part of the outside air in the outside air introduction duct 19 is transferred to the bypass duct 2.
2 to the upstream side of the blower 18 of the package air conditioner 15, and the blower 18 mixes the small amount of outside air with the cold air generated by the evaporator 17 and blows it out. to squirt.

In the above-mentioned cooling, since outside air lower than the operation stop temperature is introduced into the evaporator 17 of the package air conditioner 15, the operation is not stopped. Also, the blower 18
Since a portion of the outside air is supplied to the air conditioner, the amount of air blown does not decrease. In this case, the temperature of the cold air blown out from the air duct 20 is slightly higher than the temperature when generated in the evaporator 17, but since the cold air is directly applied to the worker, sufficient cooling can be achieved.

Note that the above operation is performed by the first, second, and third dampers 2.
Although dampers 3, 24, and 25 are opened at a constant opening degree and operated regardless of the outside temperature, it is also possible to open and close each damper 23, 24, and 25 depending on the temperature of the outside air. That is, outside air introduction duct 1
The temperature of the outside air introduced into the package air conditioner 15 is measured by the temperature sensor 26, and this measured temperature is
If the temperature is higher than the operation shutdown temperature, all dampers 2
3, 24, and 25 are opened to perform cooling as described above.

Next, if the outside air is lower than the operation shutdown temperature and higher than the cooling start temperature, the first damper 23 is opened and the second and third dampers 24 and 25 are closed, as shown in FIG. Close the return duct 21 and bypass duct 22 and open the outside air introduction duct 1.
All the outside air introduced from 9 is supplied to the evaporator 17 to turn it into cold air, and the generated cold air is directly sent to the blower 1.
8, the air is blown out through the air duct 20 into the factory for cooling.

If the outside temperature is lower than the cooling start temperature, the third
As shown in the figure, the first and second dampers 23 and 24 are closed, the third damper 25 is opened, and the outside air introduction duct 19 is closed downstream of the bypass duct 22, and the return duct 21 is closed. The outside air introduced into the outside air introduction duct 19 is supplied to the blower 18 via the bypass duct 22, and is blown out as it is by the blower 18, and then blown into the factory through the blower duct 20 for cooling.

Effects of the invention According to this invention, a cooling system is constructed using mass-produced inexpensive packaged air conditioners, and it is possible to supply cold air at an appropriate temperature to the working area of the factory without being affected by the temperature of the outside air. Furthermore, even with a small air conditioner, a sufficient amount of air can be ensured, the equipment can be downsized, and equipment costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a cooling device according to the present invention,
Figures 2 and 3 are drawings showing examples of its operation, and Figure 4.
The figure is a schematic diagram showing an example of a cooling device using a package air conditioner, and FIG. 5 is a schematic diagram of a conventional improved cooling device. 15...Package air conditioner, 16...Casing, 17...Evaporator, 18...Blower, 19...
Outside air introduction duct, 20...Blower duct, 21...
Return duct, 22...Bypass duct.

Claims (1)

[Scope of utility model registration request] Using a package air conditioner, which has refrigerant cycle equipment such as a compressor, condenser, and evaporator, as well as a blower, air filter, and automatic control mechanism built into the casing, outside air is introduced and cold air is generated internally, and this cold air is sent indoors. In the cooling device configured to send air to the air conditioner, a return duct is branched from the air blow duct of the package air conditioner, the return duct is communicated with the outside air introduction duct, and a bypass duct is branched from the outside air introduction duct on the upstream side of the return duct. , A cooling device characterized in that the bypass duct is connected to an upstream side of a blower.