JP2001091082A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the phenomenon of frosting of an outdoor side heat exchanger when heated in a heat pump type air conditioner. SOLUTION: A bypass tube 11, having heat absorbing unit 11a for absorbing a waste heat of a compressor 3, is connected at both ends to a first branch tube 8a and a second branch tube 8b of second piping 8 for connecting an outdoor side heat exchanger 4 and an indoor side heat exchanger 6 and provided at the periphery of the compressor 3. A first check valve 12 opened from the unit 11a to the tube 8a is provided at the pipe 11. A second check valve 13 opened from the exchanger 4 toward the exchanger 6 is provided between the tube 8a and the tube 8b of the piping 8.

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 heat pump type air conditioner in which waste heat of a compressor is used as a heat source for defrosting an outdoor heat exchanger during a heating operation. .

[0002]

2. Description of the Related Art In a conventional refrigerant circuit of a heat pump type air conditioner, a four-way valve 5 is connected to the discharge side of a compressor 3 in an outdoor unit 1 as shown in FIG. One of the outdoor heat exchangers 4 is connected via one pipe 7, and the indoor unit 2 is connected via a second pipe 8 having an expansion valve 14 and a two-way operation valve 15 to the other of the outdoor heat exchanger 4. Is connected to one of the indoor heat exchangers 6. The other side of the indoor heat exchanger 6 is connected to the four-way valve 5 through a third pipe 9 having a three-way operation valve 16.
The four-way valve 5 is connected to the suction side of the compressor 3 via a fourth pipe 10.

The refrigerant circuit is switched by the four-way valve 5 so that the indoor heat exchanger 6 functions as an evaporator during the cooling operation, the outdoor heat exchanger 4 functions as a condenser during the cooling operation, and the heating circuit operates during the heating operation. The indoor heat exchanger 6 functions as a condenser, and the outdoor heat exchanger 4 functions as an evaporator.
The flow of the refrigerant during the cooling operation is such that the high-temperature and high-pressure refrigerant discharged from the discharge side of the compressor 3 passes through the four-way valve 5 and passes through the first pipe 7 as indicated by a solid arrow in FIG. After reaching the outdoor heat exchanger 4 and releasing heat to the outside to condense and liquefy, it is decompressed and expanded by the expansion valve 14 of the second pipe 8 and reaches the indoor heat exchanger 6 to reach the indoor heat exchanger 6. After returning to the compressor 3 through the fourth pipe 10 through the four-way valve 5 through the third pipe 9. The flow of the refrigerant during the heating operation is such that the high-temperature and high-pressure refrigerant discharged from the discharge side of the compressor 3 passes through the four-way valve 5 and flows into the third pipe 9 as indicated by a broken arrow in FIG. After flowing into the indoor unit 2 of the indoor unit 2, the heat is released into the room and condensed and liquefied. Then, the refrigerant is decompressed and expanded by the expansion valve 14 of the second pipe 8. After reaching the outdoor heat exchanger 4 and evaporating and evaporating to absorb the outdoor heat, it passes through the first pipe 7, passes through the four-way valve 5, and returns to the compressor 3 through the fourth pipe.

[0004] During the heating operation, if the outside air temperature is low, frost may be formed on the outdoor heat exchanger 4 acting as an evaporator, and if such frost is formed, the heating effect is reduced. Defrosting needs to be performed. When performing the defrosting operation, the four-way valve 5 is switched to the cooling operation, the indoor air is used as a heat source, the outdoor heat exchanger 4 is operated as a condenser, and the outdoor heat exchanger 4 is defrosted. I do.

However, in order to perform defrosting by switching from the heating operation to the cooling operation, it is necessary to stop the compressor 3 once to reduce the high pressure and low pressure in the refrigerant circuit, and then switch the four-way valve 5. In particular, when it is necessary to perform the defrosting operation frequently, there is a problem that the heating operation of the indoor unit is interrupted and the comfort of the heating operation is impaired.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has been made to increase the temperature of a refrigerant by utilizing waste heat of a compressor when an air conditioner performs a heating operation when the outside air temperature is low.
The present invention relates to an apparatus in which a somewhat high-temperature refrigerant is circulated through an outdoor heat exchanger to prevent frost formation on the outdoor heat exchanger and reduce the frequency of defrosting operation due to frost formation.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an air system in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are sequentially connected by connecting pipes. In the conditioner, a bypass pipe provided with a heat absorbing portion that is provided around the compressor and absorbs the heat is connected in parallel to the connection pipe that connects the outdoor heat exchanger and the expansion valve, The connection pipe or the bypass pipe is provided with a valve device for switching the flow of the refrigerant to the bypass pipe.

The valve device is provided between the first check valve, which is provided in the bypass pipe and opens from the heat absorbing portion toward the connection pipe, and a connection section of the connection pipe with the bypass pipe. A second check valve that is provided and opens from the outdoor heat exchanger toward the indoor heat exchanger.

[0009] Further, the valve device comprises a three-way operation valve provided at a connection portion between the bypass pipe and the connection pipe.

[0010] Further, the heat absorbing portion is connected to the bypass pipe via a flexible tube that can expand and contract.

Further, the heat absorbing section is spirally wound around the outer periphery of the compressor.

Further, the heat absorbing portion is made of a copper pipe, and is formed so as to be spirally wound and fixed on the outer periphery of the compressor.

Further, the heat absorbing portion is spirally wound and fixed to the outer periphery of the compressor via a member having thermal conductivity.

Further, the heat absorbing portion has two inner peripheral surfaces, which are attached to the outer periphery of the compressor with almost no gap, and an outer peripheral surface provided with a suction port and a discharge port connected to the bypass pipe. It is constituted by a container formed in a heavy, substantially cylindrical shape.

Further, the container is attached to the outer periphery of the compressor via a member having thermal conductivity.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below as examples based on the attached drawings. FIG. 1 is a refrigerant circuit diagram of an air conditioner according to the present invention, and FIG. 2 is a perspective view of a main part of an outdoor unit. As shown in FIG. 1, the discharge side of the compressor 3 in the outdoor unit 1 is connected to a four-way valve 5, which is connected to one of the outdoor heat exchangers 4 via a first pipe 7. The other of the indoor heat exchanger 4 is connected to one of the indoor heat exchangers 6 of the indoor unit 2 via a second pipe 8 having an expansion valve 14 and a two-way operation valve 15. The other of the indoor heat exchanger 6 is a third pipe 9 having a three-way operation valve 16.
The four-way valve 5 is connected to the suction side of the compressor 3 through a fourth pipe 10.

Also, from the first branch pipe 8a of the second pipe 8 between the outdoor heat exchanger 4 and the expansion valve 14,
A bypass pipe 11 having a first check valve 12 in parallel with the second pipe 8 branches off, and the bypass pipe 11 is connected to the compressor 3.
, And a heat absorbing section 11 that absorbs waste heat of the compressor 3
a, and is connected to a second branch pipe 8 b of the second pipe 8 between the first branch pipe 8 a and the expansion valve 14.

Further, the first branch pipe 8 of the second pipe 8
A second check valve 13 that opens toward the flow from the outdoor heat exchanger 4 to the indoor heat exchanger 6 is provided between a and the second branch pipe 8b. The first check valve 1
2 is provided so that the flow from the heat absorbing portion 11a to the first branch pipe 8a is opened.

As shown in the perspective view of the main part of FIG. 2, the substantially cylindrical compressor 3 is mounted on the bottom plate 20 of the outdoor unit at the front and the heat transfer tube at the rear at right angles to the fins. Is placed in a meandering manner, and a motor mount 23 supporting a fan motor 22 connected to a fan 21 is provided upright at a substantially central portion.

The outdoor heat exchanger 4 is connected to the second pipe 8, and the first branch pipe 8a of the second pipe 8 is provided with the first check valve 12 as described above. The heat absorbing section 1
The bypass pipe 11 reaching 1a is connected. As shown in FIG. 2, the heat absorbing portion 11a is connected to the bypass pipe 1 via a bellows-shaped telescopic flexible tube 11b.
1 and spirally wound around the compressor 3 a plurality of times, and then connected to the bypass pipe 11 via the flexible tube 11c. It is connected to the branch tube 8b.

Next, the flow of the refrigerant will be described. During the cooling operation, the high-temperature and high-pressure refrigerant discharged from the discharge side of the compressor 3 passes through the four-way valve 5 to the outdoor heat exchanger 4 through the first pipe 7 as shown in FIG. Then, after the heat is released to the outside of the room to condense and liquefy, it flows into the second pipe 8. The refrigerant flowing into the second pipe 8 is supplied to the expansion valve 14.
, And is decompressed and expanded, and flows into the indoor heat exchanger 6 of the indoor unit 2. The refrigerant that has absorbed indoor heat in the indoor heat exchanger 6 and evaporated and vaporized passes through the four-way valve 5 via the third pipe 9 and returns to the compressor 3 via the fourth pipe 10. . The refrigerant flows into the second branch pipe 8 of the second pipe 8
b, flows into the bypass pipe 11, but reaches the first branch pipe 8 via the heat absorbing portion 11a, and flows into the second pipe 8 again because the refrigerant pressure in the first branch pipe 8 is high. I will not do it.

Next, the flow of the refrigerant during the heating operation will be described. As shown in FIG. 4, the high-temperature and high-pressure refrigerant discharged from the discharge side of the compressor 3 passes through the four-way valve 5 and passes through the third pipe 9 to the indoor heat exchanger of the indoor unit 2. 6, the heat is released into the room and condensed and liquefied, and then flows into the second pipe 8 and is decompressed and expanded by the expansion valve 14. The flow of the refrigerant that has been decompressed and expanded in the second pipe 8 is blocked by the second check valve 13 and flows into the bypass pipe 11 from the second branch pipe 8b. The refrigerant flowing into the bypass pipe 11 reaches the heat absorbing portion 11a via the flexible tube 11b, and the heat absorbing portion 11a
After absorbing the waste heat of the compressor 3 through the flexible tube 11c, it passes through the first check valve 12 and reaches the outdoor heat exchanger 4 via the first branch pipe 8a.
The refrigerant that has absorbed outdoor heat in the outdoor heat exchanger 4 passes through the first pipe 7, passes through the four-way valve 5, and returns to the compressor 3. The heat absorbing portion 11a is connected to the bypass pipe 11 by the flexible tube 11b and the flexible tube 11c, thereby preventing the vibration of the compressor 3 from being transmitted to the bypass pipe 11, and preventing the heat absorption. The portion 11a is prevented from being separated from the compressor 3.

When the heating operation is started when the outside air temperature is low, frost is formed on the outdoor heat exchanger 4, which hinders the heating operation. However, in the refrigerant circuit of the present air conditioner, the refrigerant that has absorbed the waste heat of the compressor 3 in the heat absorbing portion 11a and flows into the outdoor heat exchanger 4 through the bypass pipe 11 so that Frosting is less likely to occur in the heat exchanger 4, whereby the frequency of performing the above defrosting operation can be reduced, and the performance of the heating operation can be improved.

Next, another embodiment will be described. As shown in FIG. 5, a three-way operation valve 17 is provided at a connection portion between the connection pipe 8 and the bypass pipe 11, and when the cooling operation is performed by the three-way operation valve 17, the indoor heat transfer from the outdoor heat exchanger 4 is performed. While the flow path of the refrigerant reaching the exchanger 6 is opened, the operation is performed with the flow path of the refrigerant from the outdoor heat exchanger 6 to the bypass pipe 11 closed, and during the heating operation, the indoor heat exchanger is operated. In this example, the operation is performed with the refrigerant flow path from the indoor heat exchanger 6 to the bypass pipe 11 closed while the refrigerant flow path from the indoor heat exchanger 6 to the outdoor heat exchanger 4 is closed.

Next, another embodiment of the heat absorbing section will be described. As shown in FIG. 6, the heat absorbing portion 18 is formed by spirally winding a copper pipe around the outer periphery of the compressor 3 and fixing the copper pipe to the outer peripheral surface of the compressor 3 by brazing or the like. By manufacturing the heat absorbing portion 18 at the same time when the compressor 3 is manufactured, the workability of assembling the indoor unit can be improved. FIG. 6 further shows the heat absorbing portion 18 via a copper pipe and a member 24 having thermal conductivity on the outer peripheral surface of the compressor 3.
Thus, the waste heat of the compressor 3 can be efficiently taken into the refrigerant in the heat absorbing section 18.

Another embodiment will be described. As shown in FIG. 8, the heat absorbing portion 25 is attached to the outer circumference of the compressor 3 with almost no gap, and the outer circumference having a suction port 25 a and a discharge port 25 b connected to the bypass pipe 11. By forming it as a double substantially cylindrical container consisting of
The workability of attaching the heat absorbing section 25 to the compressor 3 can be improved. The container 25 is also attached to the compressor 3 via a member having thermal conductivity, so that the efficiency of heat absorption can be further improved.

[0027]

As described above, according to the present invention,
During the heating operation, the refrigerant in the refrigerant circuit passes through the bypass pipe,
By absorbing the waste heat of the compressor and circulating the slightly heated refrigerant to the outdoor heat exchanger, frost formation on the outdoor heat exchanger can be prevented, and the operation is temporarily stopped. Thus, the frequency of performing the defrosting operation is reduced, and the air conditioner can perform the heating operation comfortably.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram of an air conditioner according to the present invention.

FIG. 2 is a perspective view of a main part showing a configuration of an outdoor unit of the air conditioner according to the present invention.

FIG. 3 is a refrigerant circuit diagram during a cooling operation of the air conditioner according to the present invention.

FIG. 4 is a refrigerant circuit diagram during a heating operation of the air conditioner according to the present invention.

FIG. 5 is a refrigerant circuit diagram showing another embodiment of the air conditioner according to the present invention.

FIG. 6 is a main part perspective view showing a first embodiment of a heat absorbing portion of the air conditioner according to the present invention.

FIG. 7 is a perspective view of an essential part showing a second embodiment of the heat absorbing portion of the air conditioner according to the present invention.

FIG. 8 is a perspective view of a main part showing a third embodiment of the heat absorbing portion of the air conditioner according to the present invention.

FIG. 9 is a refrigerant circuit diagram of a conventional air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outdoor unit 2 Indoor unit 3 Compressor 4 Outdoor heat exchanger 5 Four-way valve 6 Indoor heat exchanger 7 First piping 8 Second piping 9 Third piping 10 Fourth piping 11 Bypass pipe 11a Heat absorption part 11b Flexible tube 11c Flexible tube 12 First check valve 13 Second check valve 14 Expansion valve 15 Two-way operation valve 16 Three-way operation valve 17 Three-way operation valve 18 Heat absorbing part 20 Bottom plate 21 Fan 22 Fan motor 23 Fan motor mount 25 Heat absorbing part (vessel) )

Claims (9)

[Claims] 1. An air conditioner in which a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are sequentially connected by a connection pipe, wherein the outdoor heat exchanger and the expansion valve are connected to each other. The connection pipe to be connected is connected in parallel with a bypass pipe provided with a heat absorbing portion that is provided around the compressor and absorbs heat, and the connection pipe or the bypass pipe is connected to the bypass pipe. An air conditioner comprising a valve device for switching a flow. 2. The valve device according to claim 1, wherein the valve device is provided in the bypass pipe, and the first check valve opens from the heat absorbing portion toward the connection pipe, and a connection between the connection pipe and the bypass pipe. 2. The air conditioner according to claim 1, further comprising a second check valve that is provided on the outside and opens from the outdoor heat exchanger toward the indoor heat exchanger. 3. 3. The air conditioner according to claim 1, wherein the valve device comprises a three-way operation valve provided at a connection between the bypass pipe and the connection pipe. 4. The air conditioner according to claim 1, wherein the heat absorbing section is connected to the bypass pipe via a flexible tube that can expand and contract. 5. The air conditioner according to claim 1, wherein the heat absorbing portion is spirally wound around an outer periphery of the compressor. 6. The air according to claim 1, wherein the heat absorbing portion is formed of a copper pipe, and is formed so as to be spirally wound and fixed on an outer periphery of the compressor. Harmony machine. 7. The air according to claim 1, wherein the heat absorbing portion is spirally wound and fixed to the outer periphery of the compressor via a member having thermal conductivity. Harmony machine. 8. The compressor according to claim 1, wherein the heat absorbing portion includes an inner peripheral surface attached to the outer periphery of the compressor with almost no gap, and an outer peripheral surface provided with a suction port and a discharge port connected to the bypass pipe. 2. The air conditioner according to claim 1, wherein the air conditioner is formed of a heavy cylindrical container. 9. The air conditioner according to claim 1, wherein the container is attached to an outer periphery of the compressor via a member having thermal conductivity.