JPH09318206A - Heat pump type air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to remove frost with high efficiency while driving continuously a heating operation and embody cost reduction even in a simple structure and correspond with an installation condition of an air conditioner with flexibility. SOLUTION: An outdoor heat exchanger is divided into a plurality of sections in the vertical direction. Each of the divided outdoor heat exchangers ranging from 8A to 8C is connected to an indoor heat exchanger 5 in parallel with a plurality of pipelines where the pipelines are connected to the inlet of a compressor 3 by way of each of two way valves 10A and 10B respectively. Moreover, the outlet of the compressor is branched and connected to each of the outdoor heat exchangers 8A to 8C by way of the two way valves 11A to 11C respectively with the piping. When frost is removed during heating operation, the flow of discharged gas from the compressor 3 is partially changed over one after another from the upper side and to the lower side and arranged to flow into each of the outdoor heat exchangers 8A to 8C, thereby performing both heating and cooling in parallel.

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 a defrosting technique for an outdoor heat exchanger that serves as an evaporator during heating operation.

[0002]

2. Description of the Related Art For example, in a separation type heat pump type air conditioner, an indoor heat exchanger of an indoor unit and an outdoor heat exchanger of an outdoor unit are connected by a refrigerant pipe to circulate a refrigerant. In such a heat exchanger, the heat exchange tubes through which the refrigerant passes are arranged in a meandering manner and have heat exchange fins through which these heat exchange tubes penetrate to increase the heat transfer area and improve the heat exchange efficiency. Is configured to increase.

Such a heat pump type air conditioner is
As is well known, during heating operation, the heat exchanger of the outdoor unit acts as an evaporator, the refrigerant takes heat of the outdoor air to evaporate, and the evaporated refrigerant gas is compressed by the compressor to exchange heat with the indoor unit. The room can be heated by radiating heat with a container. Further, during the cooling operation, the above-mentioned reverse cycle is performed, and the heat exchanger of the indoor unit becomes an evaporator, the refrigerant takes heat of the indoor air to evaporate, and the evaporated refrigerant gas is compressed by the compressor to the outdoor unit. The interior of the room can be cooled by radiating heat with the heat exchanger.

By the way, in such an air conditioner, especially when it is used in a cold region, frost adheres to the heat exchange pipes and fins of the outdoor heat exchanger which acts as an evaporator during heating operation, and the adhered frost. Gradually grows into ice blocks. When frost or ice adheres to the outdoor heat exchanger in this way, the heat exchange efficiency decreases and the heating capacity also decreases. Therefore, it is unavoidable that the discharge gas (called hot gas) from the compressor is temporarily switched to a reverse cycle similar to the one during the cooling operation described above by a timer or the like to pass frost or ice through the heat exchange pipe of the outdoor heat exchanger. A defrosting operation is performed to melt the.

[0005]

However, the heating operation is stopped during the defrosting operation.
In addition, since the indoor heat exchanger acts as an evaporator, the heat in the room is taken away, but there is a problem that the user in the room feels cold for a while.

On the other hand, Japanese Patent Publication No. 59-26225 discloses a "heat pump type air conditioner" capable of performing defrosting while performing heating operation. This heat pump type air conditioner is provided with a plurality of heat source side heat exchangers, a partition plate is close to the side surface of one heat source side heat exchanger, and the heat exchange efficiency of one side is higher than that of the other heat source side heat exchanger. It is configured so that the heat exchange efficiency of the heat source side heat exchanger is inferior, and at the time of defrosting, these heat source side heat exchangers are connected in series via the defrosting pressure reducing element to connect a plurality of heat source side heat exchangers. In addition to alternately defrosting, the refrigerant control container that communicates with the high pressure liquid part during heating is in thermal contact with the high temperature refrigerant inflow part during defrosting of the heat source side heat exchanger with poor heat exchange efficiency. It was provided by. As a result, it is possible to perform defrosting while continuing heating to some extent.

However, the one described in Japanese Patent Publication No. 59-26225 has a problem that a five-way valve for auxiliary switching of the refrigerant flow passage having a complicated structure is required in addition to the refrigerant adjusting container, which causes a problem of high cost. there were. Further, because of its structure, two heat source side heat exchangers (outdoor heat exchangers) are appropriate, and the heating capacity is halved during defrosting. 4, even if more than two
It has been necessary to increase the number of each of the two by 6, ..., and it has not been possible to flexibly cope with the installation conditions of this type of air conditioner.

Therefore, the present invention has been made in order to solve such a problem, and it is possible to efficiently perform slow frost while continuing the heating operation, and to reduce the cost with a simple structure. It is an object of the present invention to provide a heat pump type air conditioner that can realize the above, and can flexibly respond to the installation conditions of the air conditioner.

Another object of the present invention is to provide a heat pump type air conditioner capable of suppressing a decrease in heating capacity while positively defrosting.

[0010]

In order to achieve such an object, the invention according to claim 1 of the present application is such that, during heating operation, the outdoor heat exchanger serves as an evaporator and the indoor heat exchanger serves as a condenser. In a heat pump type air conditioner that heats the interior of the room, the outdoor heat exchanger is divided into a plurality of pieces in the vertical direction,
Each of the divided outdoor heat exchangers is connected in parallel to the indoor heat exchanger by piping, and each is connected to the suction port side of the compressor through a two-way valve, and the discharge port side of the compressor is branched. When piping is connected to each outdoor heat exchanger via a two-way valve, and when defrosting is performed during heating operation, part of the gas discharged from the compressor is transferred to the divided outdoor heat exchangers from the upper side to the lower side. It is designed such that heating and slow frost are performed in parallel by sequentially switching to the side and flowing.

Further, the invention according to claim 2 is the heat pump type air conditioner for heating the room, wherein the outdoor heat exchanger serves as an evaporator and the indoor heat exchanger serves as a condenser during heating operation. The outdoor heat exchanger is divided into a plurality, each divided outdoor heat exchanger is connected in parallel to the indoor heat exchanger by piping, and each is connected to the suction port side of the compressor through a two-way valve, and, The outlet side of the compressor is branched and connected to each outdoor heat exchanger via a two-way valve, and during heating operation, part of the gas discharged from the compressor is distributed to the divided outdoor heat exchangers. It is designed such that heating and slow frost are always performed in parallel by switching and flowing sequentially.

The invention described in claim 3 is likewise
In the heating operation, the outdoor heat exchanger serves as an evaporator, the indoor heat exchanger serves as a condenser, and in a heat pump type air conditioner that heats the room, the outdoor heat exchanger is divided into a plurality of parts.
Each of the divided outdoor heat exchangers is connected in parallel to the indoor heat exchanger by piping, and each is connected to the suction port side of the compressor through a two-way valve, and the discharge port side of the compressor is branched. When piping is connected to each outdoor heat exchanger via a two-way valve, the capacity of the compressor is made variable, and when defrosting is performed during heating operation, the remaining capacity of the compressor during normal heating operation is used to remove the compressor from the compressor. A part of the discharged gas of (1) is flown while being sequentially switched to each of the divided outdoor heat exchangers so that heating and slow frosting are performed in parallel.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall configuration diagram showing a heat pump type air conditioner according to a first embodiment. In the figure, 1
Is an outdoor unit, and 2 is an indoor unit. 3 in the outdoor unit 1 is a compressor for compressing a refrigerant to circulate a refrigerant circuit, and 4 is connected to a discharge port and a suction port of the compressor 3 and a refrigerant pipe of the indoor and outdoor units 1 and 2 for cooling and heating. It is a four-way valve for switching the cooling / heating flow path that switches the flow path of the refrigerant at the time.

On the other hand, 5 in the indoor unit 2 is an indoor heat exchanger pipe-connected to the four-way valve 4 in the outdoor unit 1, and functions as a condenser during heating and as an evaporator during cooling. Reference numerals 6 and 7 denote a blower fan and its fan motor in the indoor unit 2.

Further, 8A, 8B, 8 in the outdoor unit 1
C is an outdoor heat exchanger formed by vertically dividing a heat exchange tube and a heat exchange fin of a heat exchanger integrally configured as in the conventional art into three parts, and the indoor heat exchanger 5 is respectively Pipes are connected in parallel via electric expansion valves 9A, 9B, 9C whose valve openings can be adjusted. The other refrigerant ports of each of the outdoor heat exchangers 8A, 8B, 8C are connected to the four-way valve 4 via two-way valves 10A, 10B, 10C each of which is an electromagnetic valve, and the two-way valve is connected to the two-way valve. Valve 10
Two-way valve 11A provided in parallel with A, 10B, 10C,
Via 11B and 11C, it is connected to the defrosting bypass pipeline a (or b) branched from the pipeline through which the high-pressure discharge gas (hot gas) of the compressor 3 passes. A blower fan 12 and a fan motor 13 for sending outside air are provided to each of the outdoor heat exchangers 8A, 8B, 8C.

The bypass line a (or b) is
At the connection point a1 (or b1) with the original pipe, for example, 80% of the hot gas from the compressor 3 flows to the indoor unit 2 side for heating, and the remaining 20% flows to the bypass pipeline a (or b) side. Is set. Further, the compressor 3, the four-way valve 4, the fan motors 7, 13
As in the prior art, the control is performed by a control device (not shown) including a microcomputer and the opening and closing of newly provided two-way valves 10A to 10C and 11A to 11C are also controlled by the same control device.

Next, the operation of this embodiment configured as described above will be described.

During the cooling operation, the four-way valve 4 is set to the broken line state, the two-way valves 10A, 10B and 10C are set to the open state, and the two-way valves 11A, 11B and 11C for defrosting are set to the closed state. When the bypass line is indicated by the broken line b, the open state may be used. When the compressor 3 is operated, the refrigerant flows as indicated by the broken line arrow. That is, the high-temperature and high-pressure refrigerant gas discharged from the compressor 3 passes through the four-way valve 4 from the points c, d, and e of the pipe flow path, and the two-way valve 10 is in an open state.
Passing through A, 10B, 10C, each outdoor heat exchanger 8A, 8
B, 8C. Each outdoor heat exchanger 8 during cooling operation
Since A, 8B, and 8C act as a condenser, the supplied refrigerant gas is condensed and liquefied by heat exchange by the air blown from the fan 12. The refrigerant condensed and liquefied in each of the outdoor heat exchangers 8A, 8B, and 8C is expanded valve 9 in an open state.
After passing through A, 9B, and 9C, the pressure is reduced to a pressure at which it is easy to evaporate, and then merges via points f, g, and h. The combined low-pressure refrigerant liquid is supplied to the indoor heat exchanger 5 in the indoor unit 2. During the cooling operation, the indoor heat exchanger 5 acts as an evaporator to evaporate the refrigerant liquid that is depressurized and supplied, and removes heat from the air sent from the fan 6 to cool the room. Then, the evaporated and vaporized refrigerant gas is sent to the outdoor unit 1 through the refrigerant pipe, sucked into the compressor 3 through the four-way valve 4, and the above refrigerant cycle is repeated.

On the other hand, during the heating operation, the four-way valve 4 is set to the solid line state, and the two-way valves 10A to 10C are first set to the two-way valve 1.
2A valves 11A to 11C for slow frost with only 0A closed
First, when only the two-way valve 11A is set to the open state and the compressor 3 is operated, the refrigerant flows as shown by the solid line arrow and the one-dot chain line arrow. That is, 80% of the high-temperature high-pressure refrigerant gas discharged from the compressor 3 is supplied to the indoor heat exchanger 5 on the indoor unit 2 side via the four-way valve 4, and the other 20% is discharged from the branch point a1. Bypass line a
It is supplied to the uppermost outdoor heat exchanger 8A from point i through (or branch point b1 to bypass line b) via two-way valve 11A.

During the heating operation, since the indoor heat exchanger 5 acts as a condenser, the supplied high-temperature and high-pressure refrigerant gas is condensed and liquefied, and the heat radiation at this time is blown out by the blower fan 6 to heat the room. . Then, the condensed and liquefied refrigerant is sent to the outdoor unit 1 and reduced in pressure to easily evaporate through the expansion valves 9B and 9C, and then the two-way valves 10B and 1C.
0C is supplied to the outdoor heat exchangers 8B and 8C in the open state. During the heating operation, these outdoor heat exchangers 8B and 8C act as evaporators, and the supplied refrigerant liquid takes heat from the outside air blown from the fan 12 and evaporates.

On the other hand, in the uppermost outdoor heat exchanger 8A, as described above, part of the hot gas from the compressor 3 is from the branch point a1 to the bypass line a (or the branch point b1 to the bypass line b). Is supplied from the point i through the two-way valve 11A, it acts as a condenser, and the supplied high-pressure hot gas is condensed and liquefied to radiate heat. The condensed and liquefied high-pressure refrigerant liquid is sent from the point f to the point g through the expansion valve 9A. Although the refrigerant liquids from the indoor unit 2 side are sent from the point g, the refrigerant liquids from both sides join at the point g and are supplied to the outdoor heat exchanger 8B through the expansion valve 9B. In this way, the refrigerant gas evaporated and vaporized in the outdoor heat exchangers 8B and 8C are respectively two-way valves 10C and 10B and e and d.
It is sent to the point c via the point, is sucked into the compressor 3 via the four-way valve 4, and the above refrigerant cycle is repeated. In this refrigerant cycle, since the uppermost outdoor heat exchanger 8A acts as a condenser, no frost is formed, and the second and third outdoor heat exchangers 8B, 8C act as evaporators, so that they gradually become worn. Frost is coming.

Here, based on the time when frost is formed on the outdoor heat exchanger acting as an evaporator, the outdoor heat exchanger for defrosting is switched within a range below that (1/2 because there are two). Predetermine the time. As a result, when the predetermined switching time is reached in the above-mentioned refrigerant cycle,
The control device (not shown) sets the two-way valve 11A of the uppermost outdoor heat exchanger 8A, which has been defrosting up to now, to the closed state, while setting the two-way valve 10A to the open state. Almost at the same time, the two-way valve 10B of the outdoor heat exchanger 8B immediately below is set to the closed state, while the two-way valve 11B is set to the open state.

As a result, the uppermost outdoor heat exchanger 8A and the lowermost outdoor heat exchanger 8C serve as evaporators, and the second outdoor heat exchanger 8B serves as a condenser, in the same manner as described above. , Defrosting is performed in parallel with the heating operation. The same applies when defrosting the lowermost outdoor heat exchanger 8C. During this period, the heating capacity does not decrease at all, the frost does not occur on each of the outdoor heat exchangers 8A to 8C, and the heat exchange efficiency does not decrease.

As described above, in the present embodiment, conventionally, when frost is formed on the outdoor heat exchanger during the heating operation, the frost is unavoidably unavoidable. On the other hand, the idea is changed to be necessary during the heating operation. In order to prevent defrosting by always performing slow defrosting accordingly, the heating is temporarily stopped or defrosted while keeping the heat exchange efficiency of the outdoor heat exchanger at the maximum state. The heating capacity will not decrease.
Further, even if frost is formed, defrosting is performed by sequentially switching from the upper outdoor heat exchanger to the lower outdoor heat exchanger, so that the water melted by the upper outdoor heat exchanger is defrosted. Even if flows into the lower heat exchanger, the lower heat exchanger is defrosted next time, so that defrosting can be performed efficiently.
In addition, since the split outdoor heat exchanger is switched by a simple mechanism called a two-way valve, cost can be reduced and the number of divisions can be set freely, and the installation condition of the air conditioner can be improved. Can respond flexibly.

FIG. 2 is an overall configuration diagram showing a heat pump type air conditioner according to the second embodiment. The difference between the present embodiment and the above-described embodiment is that an inverter 14 that variably controls the rotation speed of the compressor 3 is provided. Others are the same as the above-mentioned embodiment. The present embodiment is provided with such an inverter 14, and operates at a rotation speed of, for example, 80% of the maximum capacity of the compressor 3 during normal heating operation, and increases the rotation speed to 100% during defrosting to provide a remaining power of 20%. %
Is used for defrosting.

Thus, defrosting can be performed in parallel without reducing the heating capacity during normal heating operation. Therefore, the defrosting can be positively performed without worrying about the decrease in the heating capacity, the frost formation can be eliminated, the heat exchange efficiency can be improved, and the heating capacity can also be improved.

In each of the above embodiments, the inverter 14 is used in order to make the capacity of the compressor 3 variable. However, for example, a so-called power saving function of returning the refrigerant in the middle of compression of the compressor to the suction side, or a compressor motor You may use the pole number conversion function which makes the number of poles of.

[0029]

As described above, according to the invention of claim 1 of the present application, the outdoor heat exchanger is divided into a plurality of parts in the vertical direction,
Each of the divided outdoor heat exchangers is connected in parallel to the indoor heat exchanger by piping, and each is connected to the suction port side of the compressor through a two-way valve, and the discharge port side of the compressor is branched. When piping is connected to each outdoor heat exchanger via a two-way valve, and when defrosting is performed during heating operation, part of the gas discharged from the compressor is transferred to the divided outdoor heat exchangers from the upper side to the lower side. The heating and slow frost are performed in parallel by sequentially switching to the side, so that slow frost can be efficiently performed while continuing the heating operation, and a simple structure can reduce cost. Further, since the number of divisions of the outdoor heat exchanger can be set relatively freely, there is an effect that the installation conditions of the air conditioner can be flexibly dealt with.

Further, according to the second aspect of the invention, the outdoor heat exchanger is divided into a plurality of parts, each of the divided outdoor heat exchangers is connected in parallel to the indoor heat exchanger by pipes, and each two-way valve is connected. Piping to the suction port side of the compressor, and branching the discharge port side of the compressor to each outdoor heat exchanger via a two-way valve to discharge the compressor during heating operation. Since a part of the gas is made to flow while being sequentially switched to each of the divided outdoor heat exchangers to perform heating and slow frost in parallel at the same time, the same effect as in claim 1 can be obtained, and the positive effect can be obtained positively. It is possible to suppress the decrease in heating capacity while gradually defrosting.

According to the third aspect of the present invention, the outdoor heat exchanger is divided into a plurality of parts, each of the divided outdoor heat exchangers is connected in parallel to the indoor heat exchanger by piping, and each two-way valve is connected. Pipe connection to the intake side of the compressor via
In addition, the outlet side of the compressor is branched and connected to each outdoor heat exchanger through a two-way valve, and the capacity of the compressor is made variable, and when defrosting during heating operation, normal heating is performed. Since a part of the gas discharged from the compressor is sequentially switched to each of the divided outdoor heat exchangers by using the remaining capacity of the compressor during operation to perform heating and slow frost in parallel, the above claim Item 1
In addition to the effect similar to the above, there is an effect that the slow frost can be positively performed and a decrease in heating capacity can be suppressed.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a heat pump type air conditioner according to a first embodiment.

FIG. 2 is an overall configuration diagram showing a heat pump type air conditioner according to a second embodiment.

[Explanation of symbols]

 1 Outdoor unit 2 Indoor unit 3 Compressor 4 Four-way valve 5 Indoor heat exchanger 6, 12 Blower fan 7, 13 Fan motor 8A-8C Outdoor heat exchanger 10A-10C, 11A-11B Two-way valve 14 Inverter

Claims (3)

[Claims] 1. A heat pump type air conditioner in which an outdoor heat exchanger serves as an evaporator and an indoor heat exchanger serves as a condenser to heat a room during a heating operation, wherein the outdoor heat exchanger is vertically divided into a plurality of parts. Each of the divided outdoor heat exchangers is connected to the indoor heat exchanger in parallel by piping, and each is connected to the compressor suction port side via a two-way valve, and the compressor discharge port side is branched. Then, when connecting to each outdoor heat exchanger through a two-way valve for piping and performing defrosting during heating operation, part of the gas discharged from the compressor is connected to the above-mentioned divided outdoor heat exchangers on the upper side. The heat pump type air conditioner is characterized in that the heating and the slow frost are performed in parallel by sequentially switching from the lower side to the lower side. 2. In a heat pump type air conditioner for heating an indoor room, the outdoor heat exchanger serves as an evaporator and the indoor heat exchanger serves as a condenser during heating operation, and the outdoor heat exchanger is divided into a plurality of parts. While connecting each outdoor heat exchanger to the indoor heat exchanger in parallel,
Each is connected to the suction port side of the compressor via a two-way valve, and the discharge port side of the compressor is branched,
A pipe is connected to each outdoor heat exchanger via a two-way valve, and during heating operation, a portion of the gas discharged from the compressor is sequentially switched to each of the divided outdoor heat exchangers to flow heating and slow frost. A heat pump type air conditioner characterized by being operated in parallel at all times. 3. A heat pump type air conditioner in which the outdoor heat exchanger serves as an evaporator and the indoor heat exchanger serves as a condenser during heating operation to heat the room, wherein the outdoor heat exchanger is divided into a plurality of parts. While connecting each outdoor heat exchanger to the indoor heat exchanger in parallel,
Each is connected to the suction port side of the compressor via a two-way valve, and the discharge port side of the compressor is branched,
When piping is connected to each outdoor heat exchanger via a two-way valve, the capacity of the compressor is variable, and when defrosting is performed during heating operation, the remaining capacity of the compressor during normal heating operation is used to remove the compressor from the compressor. A heat pump type air conditioner characterized in that a part of the discharge gas is discharged to each of the divided outdoor heat exchangers while being sequentially switched to perform heating and defrosting in parallel.