JPH1123109A - Outdoor unit of heat pump type room air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent frosting by raising the temperature of an outdoor heat exchanger, and to prevent the deterioration in heating capacity, when the heat exchanger is frosted due to the decline in the outside air temperature at the time of a heating operation. SOLUTION: By having a heat transfer means, which transfers the heat that is generated in a compressor 4 to an outdoor heat exchanger 3, and a control means which controls the operation of the heat transfer means, the temperature of the heat exchanger 3 is increased to prevent frosting through operating the heat transfer means, and then transferring the heat that is generated in the compressor 4 to the heat exchanger 3, when the outdoor heat exchanger 3 is frosted due to the decline in the outside air temperature during a heating operation. For the heat transfer means, a radiating fan 10, which is provided between the compressor and the outdoor heat exchanger, or a bypass heat exchanger piping, which transfers the exhaust heat of the compressor 4 to the outdoor heat exchanger 3 by using a refrigerant, are used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outdoor unit of a heat pump type room air conditioner which heats and cools by utilizing a phase change of a refrigerant to pump and discharge heat between a low temperature side and a high temperature side, and particularly to frost. The present invention relates to an outdoor unit capable of effectively preventing sticking.

[0002]

2. Description of the Related Art FIG. 9 is a schematic diagram of a conventional heat pump type room air conditioner, which comprises an outdoor unit 1 and an indoor unit 2. The outdoor unit 1 has a case in which an outdoor heat exchanger 3 is attached to the inner surface thereof, the compressor 4 and the expansion device 5 are connected by piping, and a temperature sensor 6 for defrosting is attached to a part of the piping. It has a built-in configuration.

The indoor unit 2 has a built-in indoor heat exchanger 7 and is connected to the compressor 4 and the expansion device 5 of the outdoor unit 1 through a refrigerant pipe 8. Is filled. During heating, a refrigeration cycle that repeatedly compresses and expands the refrigerant to pump up heat from the outdoor heat exchanger 3 on the low temperature side using the phase change of the refrigerant and release it to the room via the indoor heat exchanger 7 on the high temperature side. Can be heated. At the time of cooling, the indoor heat exchanger 7 is on the low temperature side and the outdoor heat exchanger 3 is on the high temperature side, and heat is transferred by a similar refrigeration cycle.

[0004] During the heating operation of the heat pump type room air conditioner having the above-described configuration, if the outside air temperature decreases, the temperature of the outdoor heat exchanger 3 becomes equal to or lower than zero degree, causing frost. Therefore, a defrosting temperature sensor 6 for continuously detecting the progress of the frosting is provided, and defrosting is started when a preset defrosting cycle and a defrosting start temperature condition are satisfied.

[0005]

When defrosting is performed in the outdoor unit of the conventional heat pump type room air conditioner having the above configuration, the refrigerating cycle is reversed from that in the heating operation, and the indoor unit 2 is cooled in the same manner as in the cooling operation. On the contrary, the outdoor unit 1 is heated. Therefore, the indoor heat exchanger 7 is cooled,
Since the heating operation is temporarily stopped, the room temperature decreases. Therefore, in order to prevent the room temperature from dropping excessively, a defrost cycle time is set so that defrost is not performed so frequently.

However, when the cycle time for defrosting is set as described above, the frost of the outdoor heat exchanger 3 gradually increases when the outside air temperature decreases, and the heat exchange efficiency with the outside air decreases.
Heating capacity is significantly reduced. The conventional device has a problem in that the interior of the room is hardly heated due to the decrease in the heating capacity generated as described above.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and increases the temperature of an outdoor heat exchanger when a heat exchanger is frosted due to a decrease in outside air temperature during a heating operation. It is an object of the present invention to obtain an outdoor unit of a heat pump type room air conditioner that prevents generation of frost and prevents a decrease in heating capacity.

[0008]

An outdoor unit of a heat pump type room air conditioner according to the present invention controls heat transfer means for transferring heat generated by a compressor to an outdoor heat exchanger, and controls operation of the heat transfer means. By having the control means, during the heating operation, when the outdoor heat exchanger causes frost due to a decrease in the outside air temperature, the heat transfer means is operated, and the heat generated in the compressor is transferred to the heat exchanger. Raise the temperature of the heat exchanger,
It can prevent frost.

Further, the heat transfer means is a radiating fan provided between the compressor and the outdoor heat exchanger.

Further, a heat-dissipation fan changeover switch and a heat-dissipation fan damper are provided to prevent heat transfer during cooling.

The heat transfer means includes a bypass heat exchange pipe attached to the compressor, connected to the outdoor heat exchanger, and having a bypass heat exchange solenoid valve in a part of the pipe. It is.

Further, the control means for controlling the operation of the heat transfer means utilizes a signal output from the outdoor heat exchanger temperature sensor or the outside air temperature sensor.

Further, the control means for controlling the operation of the heat transfer means utilizes a contact point of a pressure switch provided in a refrigerant pipe connecting the outdoor heat exchanger and the compressor.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a schematic configuration diagram of a heat pump type room air conditioner according to Embodiment 1 of the present invention, and includes an outdoor unit 1 and an indoor unit 2. The outdoor unit 1 has an outdoor heat exchanger 3 attached to the inner surface thereof, a compressor 4 and a throttling device 5 connected in series by piping, and a defrost temperature sensor 6 attached to a part of the piping. In one case. In addition, indoor unit 2
Has a built-in indoor heat exchanger 7 and is connected to the compressor 4 and the expansion device 5 of the outdoor unit 1 via the refrigerant pipe 8.

A refrigerant is filled in the refrigerant pipe 8, and heat is pumped from the outdoor heat exchanger 3 on the low temperature side by a refrigeration cycle in which the refrigerant is compressed by the compressor 4 and a process of expanding the refrigerant is repeated. The heat is released into the room through the indoor heat exchanger 7 on the high temperature side, and the room can be heated.

A heat radiating fan 10 is provided near the compressor 4, and rotates and stops the heat radiating fan 10 based on a signal detected by an outdoor heat exchanger temperature sensor 11 attached to the outdoor heat exchanger 3. Is provided.

In the outdoor unit 1 configured as described above, when the outdoor heat exchanger temperature sensor 11 attached to the outdoor heat exchanger 3 detects that the temperature is below a certain set temperature, the radiating fan 10 is rotated. When detecting that the temperature is equal to or higher than the predetermined temperature, the heat radiation fan 10 is stopped. Therefore,
When the temperature of the outdoor heat exchanger 3 falls below a predetermined set value and there is a possibility that frost may occur, the radiating fan 10 rotates and directs the hot air generated by the exhaust heat of the compressor 4 to the outdoor heat exchanger 3. The exhaust heat is moved by spraying, the ambient temperature of the outdoor heat exchanger 3 is raised, and the outdoor heat exchanger 3 is heated.

Therefore, even when the outside air temperature is low, the occurrence of frost can be eliminated, or the progress of frost can be delayed, and a decrease in pressure in the low-pressure side pipe of the compressor can be suppressed. As a result, the frequency of the defrosting operation is reduced, the number of times of heating stop is reduced, and the decrease in the heating capacity due to the decrease in the efficiency of the outdoor heat exchanger due to frost can be prevented and improved, and the indoor temperature can be kept constant. it can.

Embodiment 2 FIG. 2 is a schematic configuration diagram of a heat pump type room air conditioner showing a second embodiment of the present invention, and the configurations of reference numerals 1 to 10 are the same as those shown in FIG. A pressure switch 12 for low pressure of the compressor is provided in the middle of the piping toward.

In the first embodiment, the driving and stopping of the radiating fan 10 is controlled by using the output of the outdoor heat exchanger temperature sensor 11 attached to the outdoor heat exchanger 3. In the structure of the embodiment, the heat radiation fan 10 is driven and stopped by the compressor low-pressure pressure switch 12 attached to the low-pressure side pipe of the compressor 4,
The temperature of the outdoor heat exchanger 3 is raised to prevent the occurrence of frost, and the same effect as in the first embodiment can be obtained.

Embodiment 3 FIG. 3 is a schematic configuration diagram of a heat pump type room air conditioner according to Embodiment 3 of the present invention. The configuration of reference numerals 1 to 10 is the same as that shown in FIG. 1, except that an outdoor air temperature sensor 13 is provided on the surface of the outdoor unit 1, and the driving and stop of the radiating fan 10 is controlled by the outdoor air temperature sensor 13.
Is performed according to the outside air temperature detected by the control unit.
By controlling the operation of the heat radiating fan 10 in accordance with the outside air temperature, the temperature of the outdoor heat exchanger 3 is increased to prevent the occurrence of frost, and the same effect as in the first embodiment can be obtained.

Embodiment 4 FIG. 4 is a schematic configuration diagram of a heat pump type room air conditioner showing a fourth embodiment of the present invention. The configuration of reference numerals 1 to 8 is the same as that shown in FIG. 1, but the outdoor heat exchanger temperature sensor 11 is attached to the outdoor heat exchanger 3 and the bypass heat exchange pipe 14 is connected to the compressor 4 by heat conduction. Solenoid valve for bypass heat exchange which is provided as possible
Is connected to the outdoor heat exchanger 3 via the. The bypass heat exchange solenoid valve 15 opens and closes based on the output of the outdoor heat exchanger temperature sensor 11, and is controlled by a control unit that brings the refrigerant in the bypass heat exchange pipe 14 into a movable state or a stopped state. .

In the outdoor unit 1 having the above configuration, the outdoor heat exchanger 3
When the outdoor heat exchanger temperature sensor 11 attached to the air conditioner detects that the temperature is equal to or lower than a predetermined set temperature, the bypass heat exchange solenoid valve 15 is opened, and the refrigerant flows in the bypass heat exchange pipe 14. On the other hand, when the outdoor heat exchanger temperature sensor 11 detects that the temperature is equal to or higher than the predetermined temperature, the bypass heat exchange solenoid valve 15 is closed to stop the movement of the refrigerant.

When the refrigerant can flow, the exhaust heat of the compressor 4 is exchanged with the refrigerant flowing through the bypass heat exchange pipe 14,
The refrigerant is transferred to the outdoor heat exchanger 3 according to the movement of the refrigerant, and raises the temperature of the outdoor heat exchanger 3 to prevent the outdoor heat exchanger 3 from being frosted. Further, since the exhaust heat of the compressor 4 is transferred to the outdoor heat exchanger 3 via the refrigerant, the heat can be transferred more efficiently, and the frost prevention effect can be enhanced.

Embodiment 5 FIG. FIG. 5 is a schematic configuration diagram of a heat pump type room air conditioner showing a fifth embodiment of the present invention. In the figure, an outdoor unit 1 includes a compressor low-pressure switch 12 whose contacts are opened and closed by a low-pressure side pressure.
And a bypass heat exchange pipe 14 is attached to the compressor 4 so as to conduct heat, and is connected to the outdoor heat exchanger 3 via a bypass heat exchange solenoid valve 15. The bypass heat exchange solenoid valve 15 is opened and closed in conjunction with the contact point of the compressor low pressure switch 12. Other configurations are the same as those in FIG.

In the apparatus according to the present embodiment, when the temperature of the outdoor heat exchanger 3 drops so as to cause frost, the pressure in the low pressure side pipe of the compressor 4 changes. By this pressure change, the contact point of the compressor low-pressure switch 12 operates to open and close the bypass heat exchange solenoid valve 15 that controls the flow of the refrigerant in the bypass heat exchange pipe 14.

When the pressure in the low pressure side pipe of the compressor 4 decreases, the bypass heat exchange solenoid valve 15 opens, causing the refrigerant to flow in the bypass heat exchange pipe 14, and exchanging the exhaust heat of the compressor 4 with the refrigerant. Then, the heat of the refrigerant is moved to the outdoor heat exchanger 3 as the refrigerant moves, and the temperature of the outdoor heat exchanger 3 is raised.
On the other hand, when the pressure in the low-pressure side pipe of the compressor 4 rises, the bypass heat exchange solenoid valve 15 is closed, so that the movement of the refrigerant is stopped and the heating of the outdoor heat exchanger 3 is stopped.

Therefore, the presence / absence of frost on the outdoor heat exchanger 3 is detected by the compressor low-pressure pressure switch 12 and the opening / closing of the bypass heat exchange solenoid valve 15 is directly controlled. Frost can be prevented, the same effect as in the first embodiment can be obtained, and the control means for controlling the flow of the refrigerant in the bypass heat exchange pipe 14 which is the heat transfer means can be simplified and the cost can be reduced. Can be.

Embodiment 6 FIG. Also, as shown in FIG.
Even when the opening / closing control of the bypass heat exchange solenoid valve 15 for controlling the flow of the refrigerant in the bypass heat exchange pipe 14 is performed by the outside air temperature sensor 13 provided on the surface of the outdoor unit 1, the same as in the fourth embodiment. The effect of can be obtained.

Embodiment 7 Further, as shown in FIG. 7, a radiating fan changeover switch 16 is provided.
May be reversed so that the exhaust heat of the compressor 4 does not move to the outdoor heat exchanger 3 during the cooling operation. By doing so, the exhaust heat of the compressor 4 moves to the outdoor heat exchanger 3 through the gap of the radiating fan 10 during the cooling operation,
It is possible to prevent abnormal stop of the device caused by increasing the condensing pressure.

Embodiment 8 FIG. FIG. 8 shows a configuration in which a radiation fan damper 17 that is closed by its own weight when the radiation fan 10 is stopped is provided between the outdoor heat exchanger 3 and the radiation fan 10. According to the present embodiment, the radiation fan 10
Is stopped, the damper 17 for the radiating fan is closed by its own weight, so that the exhaust heat of the compressor 4 can be prevented from moving to the outdoor heat exchanger 3 side. Therefore, similarly to the seventh embodiment, during the cooling operation, the exhaust heat of the compressor 4 moves from the gap of the radiating fan 10 to the outdoor heat exchanger 3 side, and the abnormal stop of the device caused by increasing the condensation pressure is prevented. Can be prevented.

[0032]

Since the present invention is configured as described above, it has the following effects.

1) Heat transfer means for transferring the heat generated by the compressor to the outdoor heat exchanger, and control means for controlling the operation of the heat transfer means, wherein the exhaust heat of the compressor is transferred to the outdoor heat exchanger. By moving and heating, the temperature of the outdoor heat exchanger can be raised to prevent frost and prevent a decrease in heating capacity.

2) The exhaust heat of the compressor is moved to the outdoor heat exchanger by the rotation of the radiating fan and heated to eliminate frost even when the outside air temperature is low, or to delay the progress of frost. The lowering of the low pressure side pressure can be suppressed. Therefore, the frequency of the defrosting operation is reduced, the number of times of heating stop is reduced, and a decrease in the heating capacity due to a decrease in the efficiency of the outdoor heat exchanger due to frost can be prevented and improved, and the indoor temperature can be kept constant. .

3) By transferring the exhaust heat of the compressor to the outdoor heat exchanger via the refrigerant and heating, the heat can be transferred more efficiently, and the effect of preventing frost can be enhanced.

4) The presence or absence of frost on the outdoor heat exchanger is detected by the compressor low-pressure switch and the opening and closing of the bypass heat exchange solenoid valve is controlled to prevent frost on the outdoor heat exchanger. Control mechanism can be simplified, and the cost can be reduced.

5) The direction of rotation of the heat radiating fan can be switched, and the heat radiating fan damper 17 is provided between the outdoor heat exchanger and the heat radiating fan. It is possible to prevent an abnormal stop of the device caused by moving from the gap to the outdoor heat exchanger and increasing the condensing pressure.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a heat pump type room air conditioner according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a heat pump type room air conditioner showing a second embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a heat pump type room air conditioner showing a third embodiment of the present invention.

FIG. 4 is a schematic configuration diagram of a heat pump type room air conditioner showing a fourth embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a heat pump type room air conditioner showing a fifth embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a heat pump type room air conditioner showing a sixth embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of a heat pump type room air conditioner showing a seventh embodiment of the present invention.

FIG. 8 is a schematic configuration diagram of a heat pump type room air conditioner showing an eighth embodiment of the present invention.

FIG. 9 is a schematic configuration diagram showing an example of a conventional heat pump room air conditioner.

[Explanation of symbols]

1 outdoor unit, 2 indoor units, 3 outdoor heat exchangers, 4 compressors, 5 expansion devices, 6 defrosting temperature sensors, 7 indoor heat exchangers, 8 refrigerant pipes, 10 radiating fans, 11 outdoor heat exchanger temperature sensors, 12 Compressor low pressure switch
13 outside air temperature sensor, 14 bypass heat exchange pipe, 15
Bypass heat exchange solenoid valve, 16 radiating fan selector switch, 17 radiating fan damper In the drawings, the same reference numerals indicate the same or equivalent parts.

Claims (3)

[Claims] 1. An outdoor unit of a heat pump type room air conditioner, comprising: heat transfer means for transferring heat generated by a compressor to an outdoor heat exchanger; and control means for controlling the operation of the heat transfer means. 2. The outdoor unit of a heat pump type room air conditioner according to claim 1, wherein the heat transfer means is a radiating fan provided between the compressor and the outdoor heat exchanger. 3. The heat exchange means according to claim 1, wherein the heat transfer means is a bypass heat exchange pipe provided with the compressor, connected to the outdoor heat exchanger, and having a bypass heat exchange solenoid valve provided in a part of the pipe. Outdoor unit of heat pump type room air conditioner.