JPH0968355A - Air conditioner - Google Patents

Abstract

(57) [Abstract] [Problem] When the outside air temperature is lower than the temperature of the room to be cooled, such as in the winter, the compressor radiates heat to the outside without operating the compressor and operates it. It is an object to reduce the cost, extend the life of the compressor, and suppress the adverse effect of the failure of the compressor on the cooled portion. A bypass pipe 8 that bypasses the compressor 1 and guides a refrigerant gas from an evaporator 6 to a condenser 2 and a refrigerant flow path switching valve 9 that opens and closes the bypass pipe 8 are provided to connect the condenser 2 to the condenser 2. It is placed at a predetermined high position from the expansion valve 5. When the indoor temperature is higher than the outside air temperature, the refrigerant passage switching valve 9 is opened and the bypass pipe 8 is used as the refrigerant gas passage. Even when the compressor 1 is stopped, the refrigerant gas that reaches the condenser 2 due to the pressure difference of the refrigerant gas between the evaporator 6 and the condenser 2
Becomes the refrigerant liquid. Next, the refrigerant liquid is accumulated in the refrigerant descending pipe 13 located above the expansion valve 5, and jetted from the expansion valve 5 to the evaporator 6 by its own weight. In this way, the refrigerant circulates to radiate heat from the cooled portion.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a cooling device,
Particularly, the present invention relates to a cooling device that is constantly operated regardless of the outside air temperature.

[0002]

2. Description of the Related Art In recent years, air conditioners have been used not only for interpersonal air conditioning for humans, but also for electronic devices such as computer rooms and capsules containing relay electronic devices for mobile communication. The field of application for removing the generated heat is rapidly expanding.

When the outside air temperature is lower than the temperature of these objects to be cooled, it is possible to lower the heat insulation performance of the room or the capsule for housing the electronic equipment so that the generated heat can be diffused to the outside through the wall. . However, this method is inconvenient because heat flows from the outside when the outside temperature is high such as in the summer. Further, a method of directly introducing low temperature outside air into a room or a capsule and discharging heat to the outside by convection cannot be adopted because humidity and dust contained in the air adversely affect electronic devices. Therefore, in this case, a heat pipe may be used as a method of indirectly radiating heat via some working medium.

However, in many cases, the cooling device for electronic equipment as described above is required to be operated yearly or constantly, regardless of whether the environment is cold or hot in four seasons, day and night, etc.
In that case, it is necessary to use a cooling device that positively pumps heat from the cooled portion, which is a low-temperature heat source, to the outside, which is a high-temperature heat source. Here, the operation of cooling substances below the ambient temperature is called freezing, and when a system starts from one state and returns to the original state after undergoing various states, this system has performed a cycle. Now, the cooling device required here is nothing but a refrigerating cycle.

There are several types of refrigeration cycle,
The ideal and most efficient refrigeration cycle is Carnot (Ca
rnot) refrigeration cycle. Among actual refrigeration cycles, a vapor compression refrigeration cycle using a refrigerant that is a working fluid that easily evaporates has a thermodynamic state change close to that of a Carnot refrigeration cycle, and is therefore efficient. Therefore, it is widely used in refrigerators, air conditioners and the like, and the conventional air conditioner for the above-mentioned use also uses this vapor compression refrigeration cycle.

FIG. 2 is a configuration diagram of a vapor compression refrigeration cycle in a conventional cooling apparatus. The compressor 21 adiabatically compresses the refrigerant gas into an overheated refrigerant gas. The compressor 21 also has a function of supplying a driving force for circulating the refrigerant gas in the refrigeration cycle by sucking the refrigerant gas, pressurizing it, and sending it out. The condenser 22 is an air-cooled condenser and includes a fan 23. The condenser 22 rotates the fan 23 to blow air to the outer surface of the refrigerant container 24,
Dissipation of heat from the superheated refrigerant gas to the atmosphere, which is an external medium at a temperature lower than this, is promoted. This heat dissipation process is carried out isobarically, and the refrigerant gas is liquefied by heat dissipation to become a refrigerant liquid. The expansion valve 25 is a valve that depressurizes the refrigerant liquid into wet vapor in a gas-liquid mixed state. The wet steam is guided to an evaporator 26 that is in direct or indirect contact with the object to be cooled, and in the evaporator 26, the heat of vaporization from the object to be cooled is absorbed to become a refrigerant gas, while the object to be cooled is cooled. In the conventional cooling device, this expansion valve 2
5 was provided near the outlet of the condenser 22. The reason for this is that in the conduit from the condenser 22 to the next evaporator 26, the gas-liquid mixed state portion after the expansion valve 25 is made as large as possible, while the liquid phase portion before the expansion valve 25 is made as small as possible. This is because it is possible to reduce the amount of refrigerant sealed in the refrigeration cycle. The refrigerant gas discharged from the evaporator 26 is introduced into the suction accumulator 27. The suction accumulator 27 is a device that acts as a buffer in the case of a transient phenomenon of operation or an excessive amount of refrigerant filled. The refrigerant gas temporarily accumulated in the suction accumulator 27 is then sucked into the compressor 21 to complete the cycle. Further, in the conventional cooling device, the excess refrigerant storage container (charge modulator) 28 for accumulating the refrigerant liquid flowing out from the condenser is provided.

The above-mentioned conventional cooling device is an indoor unit 30.
And the outdoor unit 31, which are connected by a conduit for flowing the refrigerant. Indoor unit 30
Has an evaporator 26, and the outdoor unit 31 has a suction accumulator 27, a compressor 21, a condenser 22 and an expansion valve 25. There is no limitation on the vertical relationship between the positions of the indoor unit 30 and the outdoor unit 31, and the indoor unit 30 may be at a position higher than the outdoor unit 31.

When the outside air temperature decreases as in winter, the condensation temperature of the condenser 22 may become lower than the temperature to be maintained in the room containing the electronic equipment, and the refrigeration cycle may not operate. That is, in the refrigeration cycle, the refrigerant liquid produced by condensing the refrigerant gas in the condenser 22 due to the isobaric change is a supercooled liquid, and therefore can be decompressed by the expansion valve 25 to be in a wet vapor state. . If it is cooled too much, the condensing pressure will decrease and the change in isobaric pressure will cease, and the expansion valve 25 will not be able to turn it into wet steam.

Therefore, the conventional "low outside air temperature specification" and "annual operation specification" air conditioner controls the fan of the air-cooled condenser, and when the outside air temperature becomes low, the rotation speed of the fan is reduced to reduce the condensing temperature. Always keep the temperature inside the room containing the electronic equipment above, and keep it from getting too cold.

[0010]

As described above, in the conventional cooling apparatus for annual operation specifications, the compressor is always controlled after artificially controlling it so that the condensation temperature does not drop too much even if the outside air temperature drops. I have to drive. Therefore, there are problems that the operating cost of the compressor is high and that the life of the compressor is shortened. Regarding the life of the latter, not only the problem that the cost of repairing the cooling device is expensive, but also the problem that expensive devices such as computers to be cooled and relay electronic devices are damaged when the cooling device fails, and these computers. There is also a problem that the system and the communication system are down and the social impact is large, and it is also a problem that special consideration is required for maintenance for preventing failure of the cooling device.

In the present invention, when the outside air temperature is lower than the temperature of the room to be cooled, such as in winter, heat is radiated from the cooled part to the outside without operating the compressor, thereby reducing the operating cost. An object of the present invention is to provide a cooling device that can save the cost, prolongs the life of the compressor, and suppresses an adverse effect of a malfunction of the compressor on a cooled portion.

[0012]

A cooling device of the present invention includes a bypass pipe that bypasses a compressor and guides refrigerant gas from an evaporator to a condenser, and a refrigerant flow path switching valve that opens and closes the bypass pipe. And the condenser is at a predetermined high position from the evaporator, the expansion valve is at a predetermined low position from the condenser, and the refrigerant gas is at a higher temperature than the external medium, the refrigerant flow path switching valve Is opened, the bypass pipe is used as a flow path for the refrigerant gas, and the refrigerant gas reaches the condenser in the state where the compressor is stopped, and becomes the refrigerant liquid in the condenser and flows down to the expansion valve side. .

Here, at a predetermined high position of the evaporator of the condenser and a predetermined low position of the expansion valve of the condenser, the refrigerant gas discharged from the evaporator reaches the condenser with the compressor stopped. Then, the wet vapor of the refrigerant ejected from the expansion valve reaches the evaporator, and the refrigerant is circulated by the heat energy obtained in the evaporator and the gravity energy held in the condenser. In this determination, the flow pressure loss of the refrigerant flow has an influence due to conditions such as the cross-sectional area / shape of the cavity of the refrigerant conduit and the pipe shape. For example, for high condenser positions, the above conditions are designed to increase the conductance of the refrigerant conduit. The condition that the refrigerant liquid discharged from the condenser accumulates in the refrigerant conduit from the condenser to the expansion valve according to the refrigerant filling amount is also taken into consideration in the above determination together with the above condition.

The cooling device according to the first embodiment of the present invention is characterized in that an expansion valve is provided at the inlet of the evaporator.

The cooling apparatus according to the second embodiment of the present invention is characterized in that the refrigerant conduit from the outlet of the condenser to the expansion valve is filled with the refrigerant liquid.

A cooling device according to a third embodiment of the present invention is characterized in that a suction accumulator for accumulating a refrigerant gas is provided at the inlet of the compressor, and a bypass pipe bypasses the suction accumulator and the compressor. And

In the cooling system according to the fourth embodiment of the present invention, a suction accumulator for accumulating refrigerant gas is connected to the inlet of the compressor, a bypass pipe bypasses the suction accumulator and the compressor, and an expansion valve is provided. It is characterized in that the conduit of the refrigerant provided at the inlet of the evaporator and from the outlet of the condenser to the expansion valve is filled with the refrigerant liquid.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

[First Embodiment] FIG. 1 is a block diagram of a refrigerating cycle in a cooling device of the present invention. The compressor 1 is driven by an external power source and has a function of adiabatically compressing the refrigerant gas into an overheated refrigerant gas. Compressors are roughly classified into types such as reciprocating type, rotating type, and screw type. For the compressor 1 used here, a suitable one is selected and used according to conditions such as required refrigerating capacity. . The condenser 2 radiates heat from the refrigerant gas generated in the evaporator to the atmosphere and liquefies the refrigerant gas into a refrigerant liquid. The condenser 2 is an air-cooled condenser and has a fan 3. The fan 3 blows air to the outer surface of the refrigerant container 4 and promotes heat radiation from the refrigerant gas generated in the evaporator to the atmosphere, which is an external medium having a lower temperature than this. The expansion valve 5 is a temperature automatic expansion valve, and is provided immediately before the inlet of the evaporator 6. The temperature automatic expansion valve detects the temperature at the outlet of the evaporator in addition to the function of the expansion valve that decompresses high-pressure refrigerant liquid by expansion to reduce it to low-temperature low-pressure wet vapor in a gas-liquid mixed state. It has a control function of maintaining the state of the refrigerant at the outlet of the evaporator at an appropriate degree of superheat. The wet steam introduced to the evaporator 6 absorbs heat of vaporization from the object to be cooled and becomes a refrigerant gas, while the object to be cooled is cooled. The suction accumulator 7 is provided at the inlet of the compressor 1 and temporarily stores the refrigerant gas discharged from the evaporator 6, and serves as a buffer in the case of a transient phenomenon of operation or an excessive amount of filled refrigerant. is there.

The above construction is almost the same as that of the conventional cooling apparatus, but a bypass pipe by which the refrigerant gas from the evaporator 6 can directly flow to the condenser 2 by bypassing the suction accumulator 7 and the compressor 1. 8 and this bypass pipe 8
The refrigerant passage switching valve 9 that opens and closes is a characteristic configuration of the present cooling device.

The air conditioner is divided into an indoor unit 10 and an outdoor unit 11, which are connected by a refrigerant ascending pipe 12 and a refrigerant descending pipe 13 which are conduits for flowing the refrigerant. The indoor unit 10 has an expansion valve 5 and an evaporator 6, and the outdoor unit 11 has a suction accumulator 7, a compressor 1, a condenser 2, a bypass pipe 8 and a refrigerant flow path switching valve 9. As will be described later, the indoor unit 10 must be located lower than the outdoor unit 11. Here, unlike the conventional technique, the expansion valve 5 is provided at a low position immediately before the entrance of the evaporator 6, which is a characteristic configuration of the present cooling device.

Next, the operation of this cooling device will be described. There are two modes of operation. One is an operation mode mainly used when the outside temperature is high like summer and the phase state determined by the pressure of the refrigerant gas discharged from the evaporator 6 and the temperature thereof is a gas phase. The vapor compression refrigeration mode is used. I will call it. The other is that the evaporator 6
This is an operation mode that is mainly used when the phase state determined by the pressure of the refrigerant gas that comes out of the chamber and the temperature thereof is a liquid phase, and is called a natural liquefaction heat radiation mode.

In the vapor compression refrigeration mode, the compressor 1 is driven to absorb the heat absorbed by the evaporator 6 and compress the refrigerant in the gas phase, and the refrigerant which has become an overheated gas is radiated in the condenser 2. This is a mode in which a so-called vapor compression refrigeration cycle is performed in which the liquid phase is changed to a liquid phase. This mode can be used even when the outside air temperature is lower than the room temperature by performing fan control as in the prior art. In this operation mode, the refrigerant flow path switching valve 9 is closed, and the refrigerant flows through the suction accumulator 7 and the compressor 1 instead of the bypass pipe 8.

Next, the natural liquefaction heat radiation mode will be described. In the natural liquefaction heat radiation mode, the refrigerant flow path switching valve 9 is opened and the compressor 1
Do not drive. By opening the refrigerant flow path switching valve 9, the evaporator 6 and the condenser 2 are directly connected by the refrigerant rising pipe 12 and the bypass pipe 8. The outside surface of the refrigerant container 4 of the condenser 2 is in contact with the outside air capable of condensing the refrigerant gas, and the refrigerant gas of about room temperature flowing into the condenser 2 radiates heat to the outside through the refrigerant container 4 and is condensed. Then, it becomes a refrigerant liquid and flows out. That is, the condenser 2 is an absorption source of the refrigerant gas,
Since the evaporator 6 is the source of the refrigerant gas, the pressure of the refrigerant gas is high on the evaporator 6 side and low on the condenser 2 side. Therefore, a pressure gradient of the refrigerant gas is generated in the refrigerant ascending pipe 12, whereby the refrigerant gas rises from the evaporator 6 to the condenser 2. On the other hand, the refrigerant liquid flowing out from the condenser 2 flows down to the expansion valve 5 side. Since the refrigerant downcomer pipe 13 is located above the expansion valve 5,
The refrigerant liquid that has flowed down is stored in the refrigerant descending pipe 13. The accumulated refrigerant liquid is ejected from the expansion valve 5 by the pressure due to its own weight. The expansion valve 5 is provided immediately before the evaporator 6, and the wet vapor of the ejected refrigerant flows into the evaporator 6 due to its momentum. That is, without driving the compressor 1,
The refrigerant rises in the refrigerant ascending pipe 12 and descends in the refrigerant descending pipe 13, and circulates in the cooling device.

In the prior art, the reason why the expansion valve 5 is provided near the outlet of the condenser 2 unlike the present cooling device is that the amount of refrigerant enclosed in the refrigerant cycle can be reduced as described above. . Even if the expansion valve 5 is provided at a position closer to the inlet of the evaporator 6 than the outlet of the conventional condenser 2, it does not affect the performance of the refrigeration cycle in the vapor compression refrigeration mode. Further, in the conventional cooling device, since the expansion valve was provided near the outlet of the condenser, the excess refrigerant storage container (charge modulator) for accumulating the refrigerant liquid flowing out from the condenser was provided, but in this cooling device, Since the refrigerant liquid can be accumulated in the refrigerant downcomer 13, it is not necessary to separately provide a charge modulator.

One of the points to be noted for realizing the circulation of the refrigerant in the natural liquefaction heat radiation mode is that the driving force of the refrigerant circulation depending on the installation height difference between the indoor unit 10 and the outdoor unit 11 is lost. The second is to suppress the flow pressure loss, and the second is to establish and establish each of the gas phase portion and the liquid phase portion of the refrigerant in the circulation system so as to generate the circulation driving force. Therefore, in the present cooling device, in order to avoid the flow pressure loss in the suction accumulator 7 and the compressor 1, these are bypassed by the bypass pipe 8, and the outlet of the evaporator 6 at the lower part and the inlet of the condenser 2 at the upper part are bypassed. And are connected with low flow pressure loss. Further, when the installation height difference is increased and the amount of the refrigerant liquid in the refrigerant descending pipe 13 is increased, the descending driving force of the refrigerant in the refrigerant descending pipe 13 is increased, but in the refrigerant ascending pipe 12, the pressure gradient of the refrigerant gas is gentle. As a result, the upward driving force of the refrigerant becomes smaller due to the effect that the downward force due to the self-weight of the refrigerant gas increases, and the flow pressure loss due to the refrigerant ascending pipe 12 increases. Therefore, it is necessary to consider conditions such as the installation height difference, the cross-sectional area and shape of the cavity of the refrigerant conduit, and the shape of the piping in the design. For example, for large installation height differences, the conductance of the refrigerant conduit is increased.

When the difference between the temperature inside the room where the heat load is generated and the outside air temperature is 5 ° C. or more, the test device for confirming the operation of the air conditioner determines that the indoor heat load due to the natural liquefaction heat radiation mode operation is It can be discharged to the outside air, and the indoor unit 10 and the outdoor unit 11 are connected by a conduit that is normally used as a refrigerant flow path, and the refrigerant downcomer 13 is provided with refrigerant liquid at the outlet of the condenser 2. It was confirmed that the installation height difference was within a practical value of about 2 m when it was filled up to the vicinity.

[Second Embodiment] In the air conditioner of the first embodiment, the expansion valve 5 may be provided at a position other than immediately before the inlet of the evaporator 6. At this time, as described in the first embodiment, if the descending driving force necessary for circulation is generated by the refrigerant liquid accumulated in the refrigerant descending pipe above the expansion valve 5, the expansion valve 5 is moved to a position higher than the evaporator 6. Or, on the contrary, it may be at a low position, and the piping distance to the evaporator 6 may be any distance as long as the moist vapor of the refrigerant can flow into the evaporator 6 due to the momentum of the ejected refrigerant.

[Third Embodiment] In the air conditioner of the first embodiment, the refrigerant passage switching valve 9 may be a passage switching valve provided at a branch point between the bypass pipe and the conduit to the suction accumulator.

[Fourth Embodiment] In the first embodiment, when the vapor compression refrigeration cycle does not function due to a failure of the compressor 1, this is detected and the refrigerant flow switching valve 9 is automatically opened. It is a cooling device.

As a result, even if the equipment in the room generates heat, heat is radiated in the natural liquefaction heat dissipation mode, so that a backup function is obtained in which the temperature in the room is suppressed to the temperature according to the outside air temperature. This function has the effects of suppressing damage to electronic devices and the like in the room to be cooled in the event of a compressor failure, and increasing the time required for failure repair.

[0032]

According to the present invention, when the outside air temperature is lower than the temperature of the room to be cooled, such as in winter, the compressor is stopped and the natural liquefaction heat dissipation mode allows the outside of the cooled part to exit. Since the heat is radiated, the operating cost of the compressor can be reduced. Further, reducing the driving power of the air conditioner not only serves as a user merit that operating costs are reduced, but also meets social demands such as prevention of global warming. As an example of trial calculation, the cooling device of the present invention is used to cool an electronic device having a heating value of 5 kW in a vapor compression refrigeration mode only in summer under the weather conditions of Tokyo and in a natural liquefaction heat radiation mode in other seasons. When it is cooled with, the annual power saving rate reaches about 70%.

Further, this means that the operating time of the compressor per year is shortened, and the life of the compressor is extended, and the life cycle cost of the cooling device is reduced.

Further, even if the compressor fails, the heat is released in the natural liquefaction heat dissipation mode, so that a backup function of suppressing the temperature inside the room to the temperature corresponding to the outside air temperature can be obtained, and the adverse effect on the cooled portion can be suppressed. There is an effect.

In addition, in the cooling device according to the present invention, the fan control device for the condenser and the charge modulator, which have been conventionally required, are unnecessary, and the device can be simplified.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a refrigeration cycle in a cooling device of the present invention.

FIG. 2 is a configuration diagram of a vapor compression refrigeration cycle in a conventional cooling device.

[Explanation of symbols]

1,21 Compressor, 2,22 Condenser, 3,23 Fan, 4,24 Refrigerant container, 5,25 Expansion valve, 6,26
Evaporator, 8 bypass pipes, 9 refrigerant flow switching valve, 1
0,30 indoor unit, 11,31 outdoor unit,
12 refrigerant ascending pipe, 13 refrigerant ascending pipe.

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[Procedure amendment]

[Submission date] December 14, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction content]

FIG. 2 is a configuration diagram of a vapor compression refrigeration cycle in a conventional cooling apparatus. The compressor 21 adiabatically compresses the refrigerant gas into an overheated refrigerant gas. The compressor 21 also has a function of supplying a driving force for circulating the refrigerant gas in the refrigeration cycle by sucking the refrigerant gas, pressurizing it, and sending it out. The condenser 22 is an air-cooled condenser and includes a fan 23. The condenser 22 rotates the fan 23 to blow air to the outer surface of the refrigerant container 24,
Dissipation of heat from the superheated refrigerant gas to the atmosphere, which is an external medium at a temperature lower than this, is promoted. This heat dissipation process is carried out isobarically, and the refrigerant gas is liquefied by heat dissipation to become a refrigerant liquid. The expansion valve 25 is a valve that depressurizes the refrigerant liquid into wet vapor in a gas-liquid mixed state. The wet steam is guided to an evaporator 26 that is in direct or indirect contact with the object to be cooled, and in the evaporator 26, the heat of vaporization from the object to be cooled is absorbed to become a refrigerant gas, while the object to be cooled is cooled. In the conventional cooling device, this expansion valve 2
5 was provided near the outlet of the condenser 22. The reason for this is that in the conduit from the condenser 22 to the next evaporator 26, the gas-liquid mixed state portion after the expansion valve 25 is made as large as possible, while the liquid phase portion before the expansion valve 25 is made as small as possible. This is because it is possible to reduce the amount of refrigerant sealed in the refrigeration cycle. The refrigerant gas discharged from the evaporator 26 is introduced into the suction accumulator 27. The suction accumulator 27 is a device that acts as a buffer in the case of a transient phenomenon of operation or an excessive amount of refrigerant filled. The refrigerant gas temporarily accumulated in the suction accumulator 27 is then sucked into the compressor 21 to complete the cycle. Further, in the prior art cooling apparatus, surplus refrigerant reservoir container 2 for storing a refrigerant liquid flowing out of the condenser
8 was provided.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

When the outside air temperature decreases as in winter, the condensation temperature of the condenser 22 may become lower than the temperature to be maintained in the room containing the electronic equipment, and the refrigeration cycle may not operate. That is, in the refrigeration cycle, the refrigerant liquid produced by condensing the refrigerant gas in the condenser 22 due to the isobaric change is a supercooled liquid, and therefore can be decompressed by the expansion valve 25 to be in a wet vapor state. . If here the outside temperature is low, the condensing pressure will decrease.
Te, it become impossible to wet steam by the expansion valve 25.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

Here, at a predetermined high position of the evaporator of the condenser and a predetermined low position of the expansion valve of the condenser, the refrigerant gas discharged from the evaporator reaches the condenser with the compressor stopped. Then, the wet vapor of the refrigerant ejected from the expansion valve reaches the evaporator, and the refrigerant is circulated by the heat energy obtained in the evaporator and the gravity energy held in the condenser. In this determination, the flow pressure loss of the refrigerant flow has an influence due to conditions such as the cross-sectional area / shape of the cavity of the refrigerant conduit and the pipe shape. For example, for low There condenser position, to design the conditions as the conductance of the coolant conduit is increased. The condition that the refrigerant liquid discharged from the condenser accumulates in the refrigerant conduit from the condenser to the expansion valve according to the refrigerant filling amount is also taken into consideration in the above determination together with the above condition.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction content]

[First Embodiment] FIG. 1 is a block diagram of a refrigerating cycle in a cooling device of the present invention. The compressor 1 is driven by an external power source and has a function of adiabatically compressing the refrigerant gas into an overheated refrigerant gas. Compressors are roughly classified into types such as reciprocating type, rotating type, and screw type. For the compressor 1 used here, a suitable one is selected and used according to conditions such as required refrigerating capacity. . The condenser 2 radiates heat from the refrigerant gas generated in the evaporator to the atmosphere and liquefies the refrigerant gas into a refrigerant liquid. The condenser 2 is an air-cooled condenser and has a fan 3. The fan 3 blows air to the outer surface of the refrigerant container 4 and promotes heat radiation from the refrigerant gas generated in the evaporator to the atmosphere, which is an external medium having a lower temperature than this. The expansion valve 5 is an automatic temperature expansion valve or a capillary.
It is a squeezing device such as a tube , and is provided immediately before the entrance of the evaporator 6. In the case of an automatic temperature expansion valve , in addition to the function of the expansion valve that decompresses high-pressure refrigerant liquid by expansion to form low-temperature low-pressure wet vapor in a gas-liquid mixed state, it also detects the temperature at the outlet of the evaporator. , Has a control function of maintaining the state of the refrigerant at the outlet of the evaporator at an appropriate degree of superheat. The wet steam introduced to the evaporator 6 absorbs heat of vaporization from the object to be cooled and becomes a refrigerant gas, while the object to be cooled is cooled. The suction accumulator 7 is provided at the inlet of the compressor 1 to temporarily store the refrigerant gas discharged from the evaporator 6, and in the event of a transient phenomenon of operation or an excessive refrigerant charge amount,
It is a container that acts as a buffer.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

In the prior art, the reason why the expansion valve 5 is provided near the outlet of the condenser 2 unlike the present cooling device is that the amount of refrigerant enclosed in the refrigerant cycle can be reduced as described above. . Even if the expansion valve 5 is provided at a position closer to the inlet of the evaporator 6 than the outlet of the conventional condenser 2, it does not affect the performance of the refrigeration cycle in the vapor compression refrigeration mode. Further, in the prior art cooling apparatus, which has provided an expansion valve near the outlet of the condenser, had provided a surplus refrigerant storage container for storing a refrigerant liquid flowing out of the condenser, the refrigerant downcomer in this cooling device Since the refrigerant liquid can be accumulated in 13, it is not necessary to separately provide a refrigerant storage container .

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

One of the points to be noted for realizing the circulation of the refrigerant in the natural liquefaction heat radiation mode is that the driving force of the refrigerant circulation depending on the installation height difference between the indoor unit 10 and the outdoor unit 11 is lost. The second is to suppress the flow pressure loss, and the second is to establish and establish each of the gas phase portion and the liquid phase portion of the refrigerant in the circulation system so as to generate the circulation driving force. Therefore, in the present cooling device, in order to avoid the flow pressure loss in the suction accumulator 7 and the compressor 1, these are bypassed by the bypass pipe 8, and the outlet of the evaporator 6 at the lower part and the inlet of the condenser 2 at the upper part are bypassed. And are connected with low flow pressure loss. Further, when the installation height difference is increased and the amount of the refrigerant liquid in the refrigerant descending pipe 13 is increased, the descending driving force of the refrigerant in the refrigerant descending pipe 13 is increased . Design for its, it is necessary to consider the cross-sectional area and shape of the cavity of the installation height difference and refrigerant conduits, the conditions such as pipe-shaped. For example, for small installation height difference, to increase the conductance of the coolant conduit.

[Procedure amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

When the difference between the temperature inside the room where the heat load is generated and the outside air temperature is 10 ° C. or more, the test device for confirming the operation of the air conditioner determines that the indoor heat load due to the natural liquefaction heat radiation mode operation is It can be discharged to the outside air, and the indoor unit 10 and the outdoor unit 11 are connected by a conduit that is normally used as a refrigerant flow path, and the refrigerant liquid is introduced into the refrigerant downflow pipe 13 of the evaporator 6. It was confirmed that the installation height difference was within a practical value of about 2 m when it was filled up to near the mouth.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0035

[Correction method] Change

[Correction content]

In addition, in the cooling device according to the present invention, the fan control device for the condenser and the refrigerant storage that have been conventionally required.
There is also an effect that a container is unnecessary and the device can be simplified.

Claims (5)

[Claims] 1. A compressor for adiabatically compressing a refrigerant gas into an overheated refrigerant gas, a condenser for isobarically radiating the overheated refrigerant gas to an external medium into a refrigerant liquid, and a refrigerant liquid. An expansion valve for decompressing and converting it to wet vapor in a gas-liquid mixed state, and an evaporator that absorbs heat of vaporization when the wet vapor of refrigerant becomes refrigerant gas from the cooled portion, and a refrigerant circulation system sequentially connected. The cooling device includes a bypass pipe that bypasses the compressor and guides the refrigerant gas from the evaporator to the condenser, and a refrigerant flow path switching valve that opens and closes the bypass pipe. When the expansion valve is at a predetermined low position from the condenser and the refrigerant gas is at a temperature higher than that of the external medium, the refrigerant passage switching valve is opened and the bypass pipe is connected to the refrigerant gas passage. And with the compressor stopped, the refrigerant gas reaches the condenser, A cooling device characterized in that it becomes a refrigerant liquid in a condenser and flows down to the expansion valve side. 2. The cooling device according to claim 1, wherein an expansion valve is provided at an inlet of the evaporator. 3. The cooling device according to claim 1, wherein the refrigerant conduit from the outlet of the condenser to the expansion valve is filled with the refrigerant liquid. 4. The cooling device according to claim 1, wherein a suction accumulator for accumulating the refrigerant gas is provided at an inlet of the compressor, and a bypass pipe bypasses the suction accumulator and the compressor. apparatus. 5. The cooling device according to claim 1, wherein a suction accumulator that stores refrigerant gas is connected to an inlet of the compressor, a bypass pipe bypasses the suction accumulator and the compressor, and an expansion valve is an evaporator. A cooling device provided at an inlet, wherein a refrigerant conduit from an outlet of the condenser to an expansion valve is filled with a refrigerant liquid.