JPH09119734A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the defrosting performance by so disposing a T-shaped branch that the refrigerant tube on the four-way valve side before branching becomes horizontal and the tube after branching becomes vertical, and connecting the tube branched to the lower side to the lower side pass of an outdoor heat exchanger. SOLUTION: The refrigerant introduced from a compressor 3 to the outdoor heat exchanger 1 via a four-way valve 4 is branched to the upper and lower side passes of the exchanger 1 by a T-shaped branch 8. The vertical refrigerant tube 10b branched to the lower side is connected to the lower side pass of the exchanger 1. Thus, the branch flow of the refrigerant at the branch 8 is fed more to the lower side refrigerant tube 10b due to the gravity. Accordingly, the lower side pass refrigerant flow rate required for more heat quantity is increased due to the heat exchange with melted sherbet-like drain, and the defrosting time can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump type air conditioner, and more particularly to an air conditioner with improved refrigerant distribution characteristics of an outdoor heat exchanger.

[0002]

2. Description of the Related Art Generally, a heat pump type air conditioner has a refrigeration cycle in which a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing mechanism and an outdoor heat exchanger are connected in sequence to form a refrigeration cycle. By inverting the circulation direction of the switching refrigerant, it is possible to cool and heat the room.

By the way, when the outdoor air temperature is low during heating operation, frost is formed on the outdoor heat exchanger, and if the frost grows, the heat exchanger performance is deteriorated. Therefore, the four-way valve is switched to the cooling operation side. Defrosting operation such as frost is required.

In the reverse defrosting operation in which the four-way valve is switched to the cooling operation side, the high-temperature and high-pressure refrigerant discharged from the compressor is introduced into the outdoor heat exchanger to be heated to remove the frost adhering thereto. This reversal defrosting operation was performed in the outdoor heat exchanger 1 as shown in FIG. 4 in which the refrigerant flow path is made up of two upper and lower paths to reduce the pressure loss in the exchanger piping and improve the efficiency of the heat exchanger. In this case, since the melted and sherbet-shaped drain flows down from the upper side to the lower side along the heat exchanger fins 7, the defrosting ends earlier in the upper part than in the lower part of the heat exchanger.

Then, the refrigerant is not condensed in the heat exchange pipe 6a in the upper path, and the refrigerant remains in a gas state. On the other hand, in the heat exchange pipe 6b of the lower path, the refrigerant is condensed and becomes a liquid by heat exchange with the drain, so that the pipe flow resistance of the heat exchange pipe 6b of the lower pass is the pipe flow of the heat exchange pipe 6a of the upper pass. It becomes larger than the resistance, and it becomes difficult for the refrigerant to flow to the lower path of the outdoor heat exchanger 1.

[0006]

In an air conditioner equipped with such an outdoor heat exchanger 1, it takes a long time to defrost the lower side of the outdoor heat exchanger 1, so that the defrosting operation time becomes long. . Since the interior of the room cannot be heated during the defrosting operation, if the defrosting operation time becomes long, there is a problem that the room temperature is lowered and the comfort is deteriorated.

In order to solve such a problem, in the refrigerant pipe connecting the four-way valve and the outdoor heat exchanger, a throttle part is provided in the refrigerant pipe connecting to the upper path so that the upper and lower two-pass outdoor heat exchangers can be used. Although it has been devised to evenly adjust the flow resistance in the pipes of the upper path and the lower path during defrosting operation (Japanese Utility Model Laid-Open No. 59-189066), this configuration connects to the upper path during heating operation. Due to the resistance of the throttle portion provided in the refrigerant pipe, the flow resistance in the pipe of the upper path increases, the flow resistance in the pipe of the upper path and the lower path becomes non-uniform, and the operation efficiency of the heating operation decreases.

In order to solve the above-mentioned problems, the present invention hardly affects the normal heating operation and does not affect the in-pipe distribution path of the upper path and the lower path of the outdoor heat exchanger during the defrosting operation. The object is to realize an air conditioner with improved uniformity and improved defrosting performance.

[0009]

In order to solve the above problems, the present invention provides a refrigeration cycle in which a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing mechanism, and an outdoor heat exchanger are sequentially connected by a refrigerant pipe. In the air conditioner capable of cooling and heating operation by switching the four-way valve, the refrigerant pipe is branched between the four-way valve and the outdoor heat exchanger with a T-shaped branch, and the refrigerant on the four-way valve side before branching is branched. The T-shaped branch is arranged so that the piping is horizontal and the refrigerant piping after branching is vertical, the refrigerant piping branched to the upper side is connected to the upper path of the outdoor heat exchanger, and the refrigerant piping branched to the lower side is connected. It is connected to the lower path of the outdoor heat exchanger.

Further, according to the present invention, the refrigerant pipe is branched between the four-way valve and the outdoor heat exchanger by a T-shaped branch, the refrigerant pipe on the side of the four-way valve before branching is horizontal, and the refrigerant pipe after branching is upper. The T-shaped branch was arranged so as to be horizontal, the refrigerant pipe branched to the upper side was connected to the upper path of the outdoor heat exchanger, and the refrigerant pipe branched to the horizontal side was connected to the lower path of the outdoor heat exchanger. It is a thing.

Further, according to the present invention, the refrigerant pipe from the lower path of the outdoor heat exchanger to the pressure reducing mechanism is prevented from being higher than the outlet of the lower path of the outdoor heat exchanger, so that the inlet of the pressure reducing mechanism can exchange the outdoor heat. It is designed to be placed at a position lower than the lower path exit of the vessel.

Further, according to the present invention, the inlet height of the pressure reducing mechanism connected to the lower path with respect to the lower path outlet of the outdoor heat exchanger is such that the pressure reducing mechanism connected to the upper path with respect to the upper path outlet. It is equal to or lower than the entrance height of.

Further, according to the present invention, the outdoor heat exchanger has upper and lower two upper and lower paths, and the upper path passes the refrigerant downwardly and the lower side flows the refrigerant downwardly from the upper side during defrosting operation. It was done.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, a refrigerant pipe is branched between a four-way valve and an outdoor heat exchanger by a T-shaped branch, the refrigerant pipe on the four-way valve side before branching is horizontal, and the refrigerant pipe after branching is horizontal. The T-shaped branch is arranged vertically, the refrigerant pipe branched to the upper side is connected to the upper path of the outdoor heat exchanger, and the refrigerant pipe branched to the lower side is connected to the lower path of the outdoor heat exchanger. By
The ratio of branching to the upper and lower paths of the outdoor heat exchanger during defrost operation is higher in the lower path, and the flow resistance of the upper path and lower path during defrost operation does not affect the heating operation. It is possible to improve only the non-uniformity of the air conditioning, improve the defrosting performance and improve the comfort of heating operation.

Further, according to the present invention, the refrigerant pipe is branched between the four-way valve and the outdoor heat exchanger by a T-shaped branch, the refrigerant pipe on the side of the four-way valve before the branch is horizontal, and the refrigerant pipe after the branch is on the upper side. The T-shaped branch is arranged to be horizontal, the refrigerant pipe branched to the upper side is connected to the upper path of the outdoor heat exchanger, and the refrigerant pipe branched to the horizontal side is connected to the lower path of the outdoor heat exchanger. As a result, the branch ratio of the outdoor heat exchanger upper path and the lower path during the defrosting operation is higher in the lower path, and the upper path and the lower path during the defrosting operation do not affect the heating operation. It is possible to improve only the non-uniformity of the flow resistance of the, the defrosting performance is improved and the comfort of heating operation is improved.

Further, according to the present invention, the refrigerant pipe from the lower path of the outdoor heat exchanger to the pressure reducing mechanism does not become higher than the outlet of the lower path of the outdoor heat exchanger, so that the inlet of the pressure reducing mechanism can exchange the outdoor heat. By placing it lower than the outlet of the lower path of the heat exchanger, it becomes difficult for the liquid refrigerant to accumulate in the lower path of the outdoor heat exchanger during the defrosting operation, and there is no effect during the heating operation during the defrosting operation. It is possible to improve only the non-uniformity of the flow resistance of the upper path and the lower path, the defrosting performance is improved, and the comfort of heating operation is improved.

Further, according to the present invention, the inlet height of the pressure reducing mechanism connected to the lower path with respect to the lower path outlet of the outdoor heat exchanger is such that the pressure reducing mechanism connected to the upper path with respect to the upper path outlet. By making it equal to or lower than the inlet height of the, it becomes difficult for liquid refrigerant to accumulate in the lower path of the outdoor heat exchanger during defrosting operation, and the upper path and lower path during defrosting operation do not affect during heating operation. It is possible to improve only the non-uniformity of the flow resistance of the, the defrosting performance is improved and the comfort of heating operation is improved.

Further, according to the present invention, the outdoor heat exchanger has upper and lower two upper and lower paths, and during the defrosting operation, the upper path passes from the bottom to the top and the lower side allows the refrigerant to flow from the top to the bottom. By doing so, it becomes difficult for the liquid refrigerant to accumulate in the lower path of the outdoor heat exchanger during the defrosting operation, and only the non-uniform flow resistance of the upper path and the lower path during the defrosting operation is not affected during the heating operation. It can be improved, the defrosting performance is improved, and the comfort of heating operation is improved.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is a refrigerating cycle diagram of the first embodiment of the present invention. In heating operation, the four-way valve 4 is provided so that the high-temperature and high-pressure gas refrigerant discharged from the compressor 3 is guided to the indoor heat exchanger 2.
The indoor heat exchanger 2 radiates heat to the room to heat the room, and the refrigerant becomes a high-pressure liquid refrigerant. This refrigerant is decompressed by the decompression mechanisms 5a and 5b, becomes a low temperature low pressure gas-liquid mixed refrigerant, enters the outdoor heat exchanger 1, and absorbs heat from the outside to become a low temperature low pressure gas refrigerant and returns to the compressor 3. Air conditioning is a four-way valve 4
The refrigerant circulates in the opposite direction to the heating so as to absorb heat from the room and cool the room.

When the outside air temperature is low during the heating operation, frost forms on the outdoor heat exchanger 1, and if the frost grows, the heat exchanger performance deteriorates. Therefore, the four-way valve 4 is switched to the cooling operation side. Defrosting operation is in progress.

At this time, the refrigerant introduced from the compressor 3 to the outdoor heat exchanger 1 via the four-way valve 4 is branched by the branch 8 into the upper path and the lower path of the outdoor heat exchanger 1. here,
The branch 8 is a T-shaped branch, in which the refrigerant pipe 9 on the side of the four-way valve 4 before the diversion enters the branch 8 horizontally and the refrigerant pipes 10a, 1 after diversion
The branch 8 is arranged so that 0b is vertical, the refrigerant pipe 10a branched to the upper side is connected to the upper path of the outdoor heat exchanger 1, and the refrigerant pipe 10b branched to the lower side is connected to the outdoor heat exchanger 1.
Connected to the lower path. For this reason, a large amount of the refrigerant split in the branch 8 flows toward the lower refrigerant pipe 10b due to gravity.

Therefore, the heat exchange with the melted sherbet-like drain increases the flow rate of the refrigerant in the lower path which requires a larger amount of heat, and the defrosting can be efficiently performed. The defrosting time can be shortened. Moreover, since the branch 8 is on the merging side during the heating operation, it does not affect the refrigerant flow rates of the upper path and the lower path during the heating operation.

Also, in the first embodiment, the outdoor heat exchanger 1
The inlet height Hb of the pressure reducing mechanism 5b connected to the lower path with respect to the lower path outlet is
Inlet height Ha of the pressure reducing mechanism 5a connected to the upper path
It is lower. During the defrosting operation, more refrigerant condenses in the lower path due to heat exchange with the melted sherbet-like drain, and the liquid refrigerant easily accumulates. The head height up to 5b is lower in the lower path, and the resistance due to pushing up the refrigerant is less, so the refrigerant does not accumulate, and the flow resistance in the lower path increases and the refrigerant flow rate decreases. There is no. Therefore, the defrosting can be efficiently performed and the defrosting time can be shortened. In addition, since the refrigerant flows downward during the heating operation, there is almost no influence of the head difference.

As described above, in the first embodiment of the present invention, it is possible to improve only the non-uniformity of the flow resistance of the upper path and the lower path during the defrosting operation without affecting the heating operation, and the defrosting performance is improved. Can improve the comfort of heating operation.

Next, a second embodiment of the present invention will be described. The outline of the refrigeration cycle is the same as that of the first embodiment, and the heating operation and cooling operation methods are also the same.

In the heating operation, the reverse defrosting operation is performed in the same manner as in the first embodiment, and the refrigerant introduced from the compressor 3 to the outdoor heat exchanger 1 via the four-way valve 4 is branched to the outdoor heat exchanger. It is divided into an upper path and a lower path of 1. here,
The branch 8 is a T-shaped branch, in which the refrigerant pipe 9 on the side of the four-way valve 4 before the diversion enters the branch 8 horizontally and the refrigerant pipes 10a, 1 after diversion
0b is arranged so that one side is upward and the other side is horizontal, and the refrigerant pipe 10a branched to the upper side is connected to the upper path of the outdoor heat exchanger 1, and the refrigerant pipe 10 branched to the horizontal side is connected.
b is connected to the lower path of the outdoor heat exchanger 1. Therefore, a large amount of the refrigerant split in the branch 8 flows toward the horizontal refrigerant pipe 10b due to the inertia and gravity of the refrigerant flow.

Therefore, the heat exchange with the melted sherbet-like drain increases the flow rate of the refrigerant in the lower path, which requires a larger amount of heat, and the defrosting can be performed efficiently. The defrosting time can be shortened. Moreover, since the branch 8 is on the merging side during the heating operation, it does not affect the refrigerant flow rates of the upper path and the lower path during the heating operation.

Also, in the second embodiment, the outdoor heat exchanger 1
The refrigerant pipe 11b from the lower path to the pressure reducing mechanism 5b is
The inlet of the pressure reducing mechanism 5b is arranged at a position lower than the lower path outlet of the outdoor heat exchanger 1 so as not to be higher than the lower path outlet of the outdoor heat exchanger 1. Further, the outdoor heat exchanger 1 has two upper and lower paths, and the upper path allows the refrigerant to flow from the bottom to the top and the lower path allows the refrigerant to flow from the top to the bottom during the defrosting operation. During the defrosting operation, more refrigerant condenses in the lower path due to heat exchange with the melted sherbet-like drain, and the liquid refrigerant easily accumulates. Head height is 0
Therefore, there is no resistance due to pushing up the refrigerant as in the case of the conventional head height. Further, while the upper path flows in the direction in which the refrigerant is pushed up, the lower path flows in the direction in which the refrigerant descends, so the refrigerant flow resistance in the lower path becomes smaller. Therefore, the refrigerant does not accumulate in the lower path, and the flow resistance of the lower path does not increase and the refrigerant flow rate does not decrease. Therefore, the defrosting can be efficiently performed and the defrosting time can be shortened. Moreover, since the head difference is 0 even during the heating operation, there is no effect, and since the outdoor heat exchanger 1 during the heating operation has a large amount of the gas refrigerant component, the refrigerant flow direction has little effect.

As described above, in the second embodiment of the present invention, only the non-uniformity of the flow resistance of the upper path and the lower path during the defrosting operation can be improved without affecting the heating operation, and the defrosting performance can be improved. Can improve the comfort of heating operation.

[0031]

As is apparent from the above embodiments, the present invention divides the refrigerant pipe between the four-way valve and the outdoor heat exchanger into T-shaped branches, and the refrigerant pipe on the four-way valve side before branching is horizontal. , A T-shaped branch is arranged so that the refrigerant pipe after branching is vertical, the refrigerant pipe branched to the upper side is connected to the upper path of the outdoor heat exchanger, and the refrigerant pipe branched to the lower side is subjected to outdoor heat exchange. By connecting to the lower path of the vessel, due to heat exchange with the sherbet-like drain melted during defrosting operation, the refrigerant flow rate of the lower path that requires a larger amount of heat will increase,
The defrosting can be performed efficiently and the defrosting time can be shortened. Moreover, since the branch is on the merging side during the heating operation, it does not affect the refrigerant flow rates of the upper path and the lower path during the heating operation.

Further, according to the present invention, the refrigerant pipe is branched between the four-way valve and the outdoor heat exchanger by a T-shaped branch, the refrigerant pipe on the four-way valve side before branching is horizontal, and the refrigerant pipe after branching is on the upper side. The T-shaped branch is arranged to be horizontal, the refrigerant pipe branched to the upper side is connected to the upper path of the outdoor heat exchanger, and the refrigerant pipe branched to the horizontal side is connected to the lower path of the outdoor heat exchanger. As a result, due to heat exchange with the melted sherbet-like drain during defrosting, the refrigerant flow rate in the lower path, which requires a larger amount of heat, will increase, and defrosting can be performed efficiently. The defrosting time can be shortened. Moreover, since the branch is on the merging side during the heating operation, it does not affect the refrigerant flow rates of the upper path and the lower path during the heating operation.

Further, in the present invention, the refrigerant pipe from the lower path of the outdoor heat exchanger to the pressure reducing mechanism is prevented from being higher than the outlet of the lower path of the outdoor heat exchanger so that the inlet of the pressure reducing mechanism can exchange the outdoor heat. By placing it at a position lower than the lower path outlet of the vessel, more refrigerant condenses in the lower path due to heat exchange with the sherbet-like drain melted during defrosting operation, and the liquid refrigerant becomes Even if it easily collects, the head height from the outlet of the outdoor heat exchanger to the decompression mechanism is lower in the lower path, and there is less resistance by pushing up the refrigerant, so the refrigerant does not accumulate and the lower path The flow resistance of the refrigerant does not increase and the flow rate of the refrigerant does not decrease. Therefore, the defrosting can be efficiently performed and the defrosting time can be shortened. In addition, since the refrigerant flows downward during the heating operation, there is almost no influence of the head difference.

Further, according to the present invention, the inlet height of the pressure reducing mechanism connected to the lower path with respect to the lower path outlet of the outdoor heat exchanger is such that the pressure reducing mechanism connected to the upper path with respect to the upper path outlet. By making it equal to or lower than the inlet height of, even if more refrigerant condenses in the lower path due to heat exchange with the sherbet-like drain melted during defrosting operation Since the head height from the outlet of the lower path of the heat exchanger to the pressure reducing mechanism is 0, there is no resistance due to pushing up the refrigerant, so that the refrigerant does not accumulate and the flow resistance of the lower path increases and the refrigerant flow rate increases. It never decreases. Therefore, the defrosting can be efficiently performed and the defrosting time can be shortened. Moreover, even if the flow direction changes during the heating operation and during the defrosting operation, the head difference is 0, so there is no effect.

Further, according to the present invention, the outdoor heat exchanger has upper and lower two upper and lower paths, and during the defrosting operation, the upper path passes from the bottom to the top and the lower side allows the refrigerant to flow from the top to the bottom. By doing so, during defrosting operation, even though more refrigerant is condensed in the lower path due to heat exchange with the melted sherbet-like drain and liquid refrigerant easily accumulates, the upper path flows in a direction to push up the refrigerant. On the other hand, in the lower path, since the refrigerant flows in the direction in which the refrigerant flows downward, the refrigerant flow resistance in the lower path becomes smaller, and the refrigerant does not accumulate in the lower path. The flow resistance does not increase and the refrigerant flow rate does not decrease. Therefore, defrosting can be efficiently performed, and the defrosting time can be shortened. Moreover, since the outdoor heat exchanger during the heating operation contains a large amount of the gas refrigerant component, the influence of the refrigerant flow direction is small.

[Brief description of the drawings]

FIG. 1 is an enlarged view of a main part of the first embodiment.

FIG. 2 is an enlarged view of a main part of the second embodiment.

FIG. 3 is a refrigeration cycle diagram of the first embodiment.

FIG. 4 is an enlarged view of a main part of a conventional example.

[Explanation of symbols]

 1 Outdoor Heat Exchanger 2 Indoor Heat Exchanger 3 Compressor 4 Four-way Valve 5 Pressure Reduction Mechanism 6a Upper Pass Heat Exchange Pipe 6b Lower Pass Heat Exchange Pipe 7 Heat Exchanger Fin 8 Branch 9 Refrigerant Pipe Before Branch 10a Upper Side Refrigerant pipe branched to 10b Refrigerant pipe branched to the lower side

Claims (5)

[Claims] 1. A refrigeration cycle is constructed by sequentially connecting a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing mechanism, and an outdoor heat exchanger with a refrigerant pipe, and by switching the four-way valve, cooling and heating operations can be performed. In a possible air conditioner, the refrigerant pipe is branched with a T-shaped branch between the four-way valve and the outdoor heat exchanger,
The T-shaped branch is arranged so that the refrigerant pipe on the four-way valve side before branching is horizontal and the refrigerant pipe after branching is vertical, and the refrigerant pipe branched on the upper side is connected to the upper path of the outdoor heat exchanger. The air conditioner is characterized in that the refrigerant pipe branched to the lower side is connected to the lower path of the outdoor heat exchanger. 2. A refrigeration cycle is constructed by sequentially connecting a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing mechanism, and an outdoor heat exchanger with a refrigerant pipe, and by switching the four-way valve, cooling and heating operations can be performed. In a possible air conditioner, the refrigerant pipe is branched with a T-shaped branch between the four-way valve and the outdoor heat exchanger,
The T-shaped branch is arranged so that the refrigerant pipe on the side of the four-way valve before branching is horizontal and the refrigerant pipe after branching is horizontal with the upper side, and the refrigerant pipe branched on the upper side is used as the upper path of the outdoor heat exchanger. An air conditioner characterized by connecting and connecting a refrigerant pipe branched to a horizontal side to a lower path of an outdoor heat exchanger. 3. A refrigeration cycle is formed by sequentially connecting a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing mechanism, and an outdoor heat exchanger to form a refrigeration cycle, and by switching the four-way valve, cooling and heating operations can be performed. In a possible air conditioner, the refrigerant pipe from the lower path of the outdoor heat exchanger to the pressure reducing mechanism is not higher than the lower path outlet of the outdoor heat exchanger, and the inlet of the pressure reducing mechanism is An air conditioner characterized in that it is arranged at a position lower than the lower path outlet of the outdoor heat exchanger. 4. A refrigeration cycle is constructed by sequentially connecting a compressor, a four-way valve, an indoor heat exchanger, a decompression mechanism, and an outdoor heat exchanger with a refrigerant pipe, and by switching the four-way valve, cooling and heating operations can be performed. In a possible air conditioner, the inlet height of the decompression mechanism connected to the lower path with respect to the lower path outlet of the outdoor heat exchanger, the inlet pressure of the decompression mechanism with respect to the upper path outlet, the decompression connected to the upper path An air conditioner characterized by being equal to or lower than the entrance height of the mechanism. 5. A refrigeration cycle is formed by sequentially connecting a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing mechanism, and an outdoor heat exchanger to form a refrigeration cycle, and by switching the four-way valve, cooling and heating operations can be performed. In a possible air conditioner, a refrigerant pipe is branched between the four-way valve and the outdoor heat exchanger so that the outdoor heat exchanger has upper and lower two upper and lower paths, and an upper path during defrosting operation. The air conditioner is characterized in that the refrigerant flows from the bottom to the top and the bottom from the top to the bottom.