JPS636791B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat pump type room air conditioner, and more particularly to a heat pump type room air conditioner in which a solar heat collector is directly connected to a compression type heat pump heating device.

First, a conventional heat pump room air conditioner in which a solar heat collector is directly connected to a compression heat pump heating device will be explained.

Figure 1 is a diagram of the refrigerant circulation system of a conventional heat pump room air conditioner in which a solar heat collector is directly connected to a compression heat pump heating system.
It is a Mollier diagram of the refrigeration cycle of the heat pump room air conditioner according to the conventional example shown in the figure.

In Fig. 1, 1 is a main compressor, 2 is a discharge pipe,
3 is a four-way valve, 4 is a four-way valve discharge pipe, 5 is a radiator, 6
is a capillary tube related to the expansion device, 7 is a heat absorber, 8 is a four-way valve return pipe, 9 is a suction pipe, 10 is a solar heat collector, 11 is a radiator air circulation device, 12
13 is a heat absorber air circulation device, 13 is a solenoid valve in front of the heat absorber,
14 is a solenoid valve, 15 is a branch pipe, 16 is a confluence pipe,
Each is shown below.

The heat pump room air conditioner configured in this manner can use the solar heat source and the air heat source separately.

First, heating operation using a solar heat source is as follows:
The pre-heat absorber solenoid valve 13 is closed and the solenoid valve 14 is held open to perform the refrigeration cycle operation.

Hereinafter, the heating effect in this refrigeration cycle operation will be explained by referring to the Mollier diagram in Fig. 2.
The description will be made in accordance with changes in the state of the refrigerant in the refrigerant circulation channel indicated by solid arrows in the figure. However, in Fig. 2, the space between AB shows adiabatic compression, the space between BC shows heat radiation, the space between CD shows expansion, and the space between DA shows heat absorption.

High pressure, low enthalpy liquid refrigerant C after radiator 5
is expanded by the capillary tube 6 and converted into a low-pressure, low-enthalpy gas-liquid two-phase refrigerant D, which is sent to the solar heat collector 10. In this solar heat collector 10, a low-enthalpy gas/liquid two-phase refrigerant D is heated by solar heat and converted into a low-pressure, high-enthalpy vapor refrigerant A. It is returned through the suction pipe 9 into the cylinder (not shown) during the suction stroke of the main compressor 1.

From this point, the main compressor 1 enters the compression stroke and adiabatically compresses the vapor refrigerant A to produce high temperature and high pressure vapor refrigerant B. It reaches the heat radiator 5 through the. The radiator 5 sucks in cold indoor air through a radiator air circulation device 11, radiates heat at the same time, and blows warm air into the room to heat the room. Thereafter, the refrigerant continuously flows through the same system path.

On the other hand, when heating is performed using an air heat source, the electromagnetic valve 13 in front of the heat absorber is opened and the electromagnetic valve 14 is switched to a closed state and maintained, and a refrigeration cycle operation similar to the heating operation when using the solar heat source is performed. Do the following. However, in the case of an air heat source, the low-pressure, low-enthalpy gas-liquid two-phase refrigerant D from the capillary tube 6 onward is sent to the heat absorber 7, where it is heated to a temperature higher than the refrigerant evaporation temperature by the heat absorber air circulation device 12. It sucks in outdoor air, absorbs heat at the same time, and discharges the cooled air outdoors for heat exchange. From then on,
The refrigerant that has absorbed heat returns to the main compressor 1 and is transferred from the main compressor 1 to the radiator 5 in the same way as when solar heat is used as the heat source.
The high-temperature, high-pressure vapor refrigerant B continues the refrigeration cycle that heats the room.

However, this conventional heat pump room air conditioner in which a solar heat collector is directly connected to a compression heat pump heating device has the following drawbacks.

First, the solar heat source and the air heat source, which are the heat sources to be used, must be switched between them using the heat absorber front solenoid valve 13 and the solenoid valve 14 according to the local weather conditions. If this switching is to be done manually, the switching may be frequent depending on the weather conditions, making the operation cumbersome. In addition, in order to automatically switch by electrical control, the amount of solar radiation that changes depending on the daily weather, changes in the amount of solar radiation in a day, changes in cloud cover, geographical conditions, etc. is detected, and the solenoid valve 13 in front of the heat absorber , the electromagnetic valve 14 is opened and closed, and controlling this system requires a large number of control elements and the control circuit becomes complicated.

Second, regardless of whether a solar heat source or an air heat source is used, the pressure difference between high and low pressure is large because the capillary tube 6, which has a certain flow resistance, is used. Heating cannot be performed unless a large amount of power, which is almost constant, is supplied to the main compressor 1.

The present invention eliminates the above-mentioned drawbacks of the prior art,
The object of the present invention is to provide a heat pump type room air conditioner that consumes less power and is inexpensive, in which a solar heat collector is directly connected to a compressor heat pump heating device.

The feature of the heat pump type room air conditioner of the present invention is that in the heat pump type room air conditioner, the air flow from the discharge pipe of the main compressor, through the four-way valve discharge pipe related to the four-way valve, through the radiator, the expansion device, and the heat absorber, and then the air flow related to the four-way valve. In addition to the four-way valve return pipe, a separate suction pipe is provided from the four-way valve to the suction port of the main compressor. After passing through the heat collector, it is again branched into two directions, and one of the branches is conduited through an electromagnetic on-off valve to an injection port that opens into the cylinder during the compression stroke of the main compressor. A solar heat pump device by Ingeexsion,
The heat pump room air conditioner is equipped with a solar heat pump device using a small compressor, the other branched end of which is connected to the four-way valve discharge pipe via a small compressor with a smaller displacement than the main compressor.

More specifically, the high-temperature, high-pressure refrigerant discharged from the main compressor is passed from the discharge pipe through the four-way valve, through the four-way valve discharge pipe, the radiator, the expansion device, the heat absorber, and the suction pipe to the suction port of the main compressor. A main refrigeration cycle that returns to Connect the other branched pipe to the injection port that opens in the middle of the compression stroke of the main compressor, connect it to a small compressor whose displacement is much smaller than that of the main compressor, and then connect the discharge port of the small compressor to the injection port. Piping is arranged so that the refrigerant returns to the inlet of the radiator from the confluence pipe, and the injection system line and the small compressor line form two solar heat pump devices, and heating heat sources are generated from both the solar heat source and the air heat source. This makes it possible to selectively perform heating operation according to the required heating capacity.

The present invention will be explained below with reference to Examples.

FIG. 3 is a refrigerant circulation system diagram of a heat pump type room air conditioner according to an embodiment of the present invention, and FIGS.
FIG. 6 is a Mollier diagram showing the state of the refrigerant in three modes of operation using solar heat;
The figure is a Mollier diagram of the refrigerant cycle of the heat pump type room air conditioner shown in Fig. 3 during heating operation (only the main compressor is in operation) using a solar heat pump device using an injector in combination with the air heat source. Figure 6 is a Mollier diagram of a refrigeration cycle for heating operation (running the main compressor and small compressor) using a solar heat pump device using a small compressor in combination with an air heat source, and the heat pump type according to Figure 3. It is a Mollier diagram of a refrigeration cycle of a room air conditioner in a heating operation (only a small compressor is operated) using only a solar heat pump device using a small compressor.

In Figure 3, the same numbers as in Figure 1 indicate the same parts, and in Figures 4, 5, and 6, the same symbols as in Figure 2 indicate the same refrigerant state. shows.

Reference numeral 17 indicates a branch pipe provided on the exit side of the solar heat collector 10, and 21 indicates one direction from the branch pipe 17 and opens into the cylinder of the main compressor 1 during the compression stroke of the main compressor 1. an injection conduit communicating with an injection exit port (not shown);
18 is an electromagnetic on-off valve provided in the injection conduit 21, and 20a is a confluence pipe 2 which branches from the branch pipe 17 to the other side and is provided in the four-way valve discharge pipe 4.
2 is a branch pipe connected to the branch pipe 20a.
The small compressor 19, which has a smaller displacement than the main compressor 1, is an electromagnetic on-off valve provided on the suction side of the small compressor 20 in the branch pipe 20a.

The solar heat pump device in this embodiment includes a branch pipe 15, a solar heat collector 10, and a branch pipe 1.
7, Solenoid on-off valve 18, injection conduit 2
1. This part consists of a branch pipe 20a, an electromagnetic on-off valve 19, a small compressor 20, and a merging pipe 22.

The heating effect of the solar heat pump device configured as described above will be explained.

First, as a general state of solar heat utilization, the number of collectors (not shown) of the solar heat collector 10 is 1 to 1.
Solar heat pump heating (i.e., solar heat pump heating that uses a combination of the main refrigeration cycle and injection refrigeration cycle) is suitable for cases where the total heating capacity cannot be covered by solar heat alone due to high cloud cover and an air heat source is also used. (Heating using a solar heat pump device using an injection system) will be explained according to the solid line arrows in FIGS. 3 and 4.

In addition, the space between CE and CE in Figure 4 shows the expansion effect due to the flow resistance of the long pipe from the outlet of the radiator 5 to the solar heat collector 10, and the space between EG shows the solar heat collection at intermediate pressure by the refrigeration cycle using injection extension. Show action.

In this case, the electromagnetic on-off valve 18 is opened, the electromagnetic on-off valve 19 is closed, and the small compressor 20 is stopped.
Only main compressor 1 is operated.

High pressure, low enthalpy liquid refrigerant C exiting the radiator 5
The branch pipe 15 divides the flow into the heat absorber 7 direction and the solar heat collector 10 direction.

First, the refrigerant flow in one main refrigeration cycle undergoes an expansion action called CD by the capillary tube 6, and changes into a gas-liquid two-phase refrigerant D with a low pressure and low enthalpy at a temperature lower than the outdoor temperature, which absorbs heat. We reach vessel 7. In the heat absorber 7, outdoor air is sucked in by the heat absorber air circulation device 12, heat is absorbed at the same time, and the cooled air is discharged outdoors.
A low-pressure, high-enthalpy vapor refrigerant A is produced by performing an endothermic action called DA. From this, it flows from the four-way valve return pipe 8 through the four-way valve 3 and the suction pipe 9 into a cylinder (not shown) in the suction stroke of the main compressor 1.

At the same time, the flow of the refrigerant in the refrigeration cycle from the other injection branch, which is separated by the branch pipe 15, reaches the solar heat collector 10 through a long pipe. An expansion device such as a capillary tube may be added in the middle of this pipe, but the solar heat collector 10
Since the solar heat collector 10 is installed outside the building, such as on the roof or on the ground, the conduit leading to the solar heat collector 10 will be very long, and the conduit resistance will also be large. work. Due to this expansion, the pressure after the solar heat collector 10 is reduced by the main compressor 1.
The pressure is maintained at an intermediate pressure between the discharge pressure and the suction pressure. In the solar heat collector 10, a medium-pressure, high-enthalpy superheated vapor refrigerant is produced, and this refrigerant is branched in a branch pipe 17, and connected to an injection conduit 2 via electromagnetic shut-off valves 18 and 19, respectively.
The flow is divided into one direction and a small compressor 20 direction. However, since the electromagnetic on-off valve 19 is closed, the refrigerant flows only in the direction of the injection conduit 21. The vapor refrigerant is forced into the cylinder at an intermediate pressure from the injection conduit 21 to an injection port (not shown) communicating with the cylinder in the middle of the compression stroke of the main compressor 1.

At this time, the vapor refrigerant A that has passed through the main refrigeration cycle system has already been sucked into the cylinder from the suction port of the main compressor 1 in the cylinder of the main compressor 1, passes through the suction stroke, and completes the compression stroke AF. in a state. For this reason, the medium-temperature refrigerant sucked in from the injection port and the refrigerant F, whose temperature has risen due to adiabatic compression in the cylinder, mix and become vapor refrigerant G, whose temperature has dropped somewhat compared to refrigerant F.
Enters the compression process of GB ₁ . From this, main compressor 1
A high-temperature, high-pressure superheated vapor refrigerant B ₁ is produced from the discharge port of the refrigerant, and is sent to the radiator 5 via the discharge pipe 2 , the four-way valve 3 , and the four-way valve discharge pipe 4 . In this radiator 5, indoor air is circulated through the radiator 5 by the radiator air circulation device 11, so the cold indoor air is sucked into the suction port of the radiator 5, and heat is generated from the high temperature refrigerant flowing through the radiator 5. The heat is radiated to the air side, and warm air is blown out from the outlet of the radiator 5, heating the room. After radiating heat, the refrigerant returns to the original branch pipe 15 and circulates again in the same refrigeration cycle as described above to perform the heating function.

By the way, in the above-mentioned refrigeration cycle using injection extraction, due to physical constraints between the cylinder and rollers of the main compressor 1, the injection extraction conduit 21
Also, since the inner diameter of the injection exit port (not shown) cannot be made large, there is a limit to the amount of refrigerant that can be circulated through the injection exit system.

In such a case, the electromagnetic on-off valve 18 is closed, the electromagnetic on-off valve 19 is opened, the small compressor 20 is started, and the small compressor 20 is operated in parallel with the main compressor 1. heating operation using heat pump equipment). This operating mode is shown in a Mollier diagram as shown in FIG.

In addition, CD ₁ in FIG. 5 indicates the expansion effect due to the flow resistance of the long pipe from the outlet of the radiator 5 to the solar heat collector 10, and D ₁ A ₁ indicates the expansion effect due to the flow resistance of the long pipe from the outlet of the radiator 5 to the solar heat collector 10.
A 1 B 1 shows the solar heat collection effect at intermediate pressure by the refrigeration cycle, and A ₁ B ₁ shows the compression effect by a small compressor. The refrigerant circulation paths of the two refrigeration cycles, that is, the main refrigeration cycle and the refrigeration cycle using the small compressor, are as shown by solid and broken arrows in FIG. 3, with the flow in the injection conduit 21 stopped. Small compressor 20 used here
shall be a small compressor with a cylinder whose displacement is as small as possible commensurate with the amount of solar heat collected.

The heating function according to this mode of operation is as follows.

As mentioned above, the main refrigeration cycle consists of the main compressor 1
The refrigerant circulation path returns to the main compressor 1 via the radiator 5, branch pipe 15, capillary tube 6, absorber 7, four-way valve 3, and suction pipe 9. In addition, the refrigeration cycle using a small compressor is a small compressor 20.
From there, a refrigerant circulation path is taken which returns to the small compressor 20 via the confluence pipe 22, the heater 5, the branch pipe 15, the solar heat collector 10, the branch pipe 17, and the electromagnetic shut-off valve 19.

The state changes of the refrigerant during the main refrigeration cycle are as described above. In addition, the state change and function of the refrigerant during the refrigeration cycle by a small compressor is that after the branch pipe 15, due to the expansion action CD ₁ due to the pipe resistance, it becomes an intermediate pressure, low enthalpy gas/liquid two-phase refrigerant D ₁ , which collects solar heat. The refrigerant enters the vessel 10, becomes intermediate pressure, high enthalpy vapor refrigerant _A1 due to the endothermic action of _D1A1 , and reaches the branch pipe 17.The solenoid shutoff valve ₁₈ is closed and the solenoid shutoff valve 19 is open, so that the solenoid shutoff valve 19 direction The small compressor 20 compresses A ₁ B ₁ and generates high pressure.
A high-enthalpy superheated vapor refrigerant B ₁ is produced, which reaches the radiator 5 through the confluence pipe 22 and performs a heating effect. As the amount of solar heat collected increases, the amount of refrigerant circulated through the small compressor system increases, and the heating capacity also increases, but the work of the main compressor 1 is reduced and the small compressor 20 is operated with less electricity. Since the specific gravity is shifted to , a large heating capacity can be obtained with less electricity overall, resulting in extremely efficient operation.

Next, when the weather is clear and there is a sufficient amount of solar heat collected, only the small compressor 20 is operated to perform heating.

In this case, the electromagnetic on-off valve 18 is closed and the electromagnetic on-off valve 19 is opened, the main compressor 1 is stopped, and only the small compressor 20 is operated.

This heating operation takes the refrigerant circulation path shown by the broken line arrow in Fig. 3, and the refrigeration cycle as shown in the Mollier diagram A ₁ ′ → B ₁ ′ → C → D ₁ ′ shown by the solid line in Fig. 6. Do the following.

The heating function according to this mode of operation is as follows.

The condensed liquid refrigerant C under high pressure after the radiator 5 flows only in the direction of the solar heat collector 10 from the branch pipe 15, and due to the expansion effect CD ₁ due to the pipe resistance, the pressure is higher than the suction pressure in the main refrigeration cycle. A low enthalpy gas/liquid two-phase refrigerant D ₁ is produced under pressure and sent to the solar heat collector 10 . Here, as the amount of heat received from solar heat exceeds the required heating capacity, the refrigerant pressure in this portion increases, becoming superheated vapor refrigerant with a small specific volume and approaching the discharge pressure. The superheated vapor refrigerant A ₁ produced here reaches the branch pipe 17 through a long pipe line. In this branch pipe 17, the main compressor 1 is stopped, the electromagnetic on-off valve 18 is closed, and the solenoid valve 19 is open, so that refrigerant flows only in the direction of the small compressor 20. The high/medium pressure vapor refrigerant A ₁ with a small specific volume sucked into the small compressor 20 is compressed into high pressure/high enthalpy superheated vapor B ₁ by the compression action A ₁ B ₁ , and is transferred from the branch pipe 20a to the confluence pipe. It is sent to the radiator 5 via 22 to heat the room.

In this embodiment, the electromagnetic on-off valve 19 is provided on the suction side of the small compressor 20 in the branch pipe 20a provided with the small compressor 20.
When the small compressor 20 is stopped, the valve and roller of its cylinder portion are closed and act as an on-off valve, so the electromagnetic on-off valve 19 does not need to be provided.

The effects of the embodiment described above will be explained with reference to FIG. 7.

Figure 7 shows the coefficient of performance of the conventional example according to Figure 1;
FIG. 4 is a heating performance diagram showing a comparison of coefficients of performance of the embodiment according to FIG. 3;

In this Figure 7, the horizontal axis represents the amount of solar heat collected,
The vertical axis indicates the coefficient of performance indicating the heating capacity with respect to the compression work. And, a is the coefficient of performance of the heating operation in the case of using a solar heat source in the conventional example according to FIG. 1, and b is the coefficient of performance of the heating operation in the example according to FIG. 3.
d is the coefficient of performance of a heating operation using a solar heat pump device using an injection engine in combination with an air heat source; d is the coefficient of performance of a heating operation using a solar heat pump device using a small compressor in combination with an air heat source; 3 shows the coefficient of performance of the heating operation using only the solar heat pump device using a small compressor in the example shown in FIG. 3.

(1) In conventional heat pump room air conditioners,
Since the difference between the discharge pressure and suction pressure of the main compressor 1 is large, the compression work also becomes large, AB (Fig. 2). Therefore, it is necessary to supply a large amount of power commensurate with the compression work. This is the seventh
Looking at the coefficient of performance in the figure, the coefficient of performance a remains constant regardless of the amount of solar heat collected.

On the other hand, if the operation mode of the embodiment shown in FIG. 3 is performed using a solar heat pump device using an injector extension in combination with an air heat source, this compression work will be the sum of AF and GB ₁ (the fourth (Figure), and as more refrigerant flows through the injection system, the compression work becomes smaller compared to the conventional heat pump room air conditioner. Therefore, as the amount of solar heat collected increases, the coefficient of performance change b increases, and high heating performance can be obtained. Furthermore, when the amount of solar heat collected in the injection system is increased, the coefficient of performance b becomes constant at a certain point due to the physical constraints of the cylinder and rollers of the main compressor 1.

At this point, if the refrigerant circulation to the injection system is stopped, the small compressor 20 is started, and the operation mode is switched to a solar heat pump device using the small compressor in conjunction with the air heat source, the compressor work will be AB. Addition of A ₁ B ₁ (Figure 5)
As more refrigerant flows through the small compressor system, the compression work becomes much smaller than that of a conventional heat pump room air conditioner, so the coefficient of performance changes by d, making it possible to obtain even higher heating performance. .

By the way, when the main compressor 1 is stopped and the operation mode is switched to a solar heat pump device using only the small compressor 20, the coefficient of performance changes by e as the amount of solar heat collected increases, and the solar heat When the amount of heat collected is close to the maximum amount of solar radiation under clear skies, operation can be performed with a much higher coefficient of performance than each of the above-mentioned operations.

Therefore, ON/OFF of the main compressor 1, small compressor 20, and electromagnetic shut-off valves 18 and 19 are selected according to the amount of solar heat collected, and an operating mode suitable for the amount of heat collected (the one shown in FIG. 7 or ), it is possible to operate a high-performance solar heat pump device shown in bold line. Therefore, greater power saving effects can be achieved compared to conventional heat pump type room air conditioners.

(2) The solar heat collector 10 of the solar heat pump device can be used even if the area is smaller than the required heat collection area, and solar heat collectors 10 can be added one after another according to the required indoor heating capacity. It has extremely high economic value.

(3) In addition, even if the amount of solar heat collected becomes extremely small, the heat pump system using solar heat using injector and the heat pump system using air heat source can operate continuously while complementing each other. When the heating capacity is insufficient, there is no need to stop the solar heat pump cycle and switch to only operate the air heat source heat pump, which requires a large amount of electricity, and these operations can be performed automatically and continuously.

(4) In addition, the main compressor 1 and the small compressor 20 can be operated in parallel and used together with the air heat source to perform heating operation using a solar heat pump device using the small compressor. High heating performance can be obtained by solving the problem that the coefficient of performance does not increase due to a limit on the amount of refrigerant circulating through the injection path during heating operation using a solar heat pump device.

As explained in detail above, according to the present invention, in a heat pump type room air conditioner, from the discharge pipe of the main compressor, through the four-way valve discharge pipe related to the four-way valve, the four-way valve is The four-way valve is attached to the main refrigeration cycle, and a suction pipe is separately provided from the four-way valve to the suction port of the main compressor, and branched from the outlet side of the radiator. The injector is branched into two directions again through a solar heat collector, and one of the branches is conduited through an electromagnetic on-off valve to an injexion port that opens into the cylinder in the middle of the compression stroke of the main compressor. and a solar heat pump device using a small compressor, the other branched end of which is connected to the four-way valve discharge pipe via a small compressor with a smaller displacement than the main compressor. Therefore, it is possible to provide a heat pump room air conditioner that consumes less power and is inexpensive, with a solar heat collector directly connected to a compression heat pump heating device.

[Brief explanation of the drawing]

Figure 1 is a diagram of the refrigerant circulation system of a conventional heat pump room air conditioner in which a solar collector is directly connected to a compression heat pump heating system, and Figure 2 is a diagram of the refrigerant circulation system of a heat pump room air conditioner according to the conventional example shown in Figure 1. FIG. 3 is a Mollier diagram of the refrigeration cycle; FIG. 3 is a refrigerant circulation system diagram of a heat pump room air conditioner according to an embodiment of the present invention; FIG. 4 is a diagram showing the air heat source of the heat pump room air conditioner according to FIG. Figure 5 shows a Mollier diagram of a refrigeration cycle for heating operation using a solar heat pump device by Indexion in conjunction with a solar heat pump using a small compressor as an air heat source in the heat pump type room air conditioner shown in Figure 3. Fig. 6 is a Mollier diagram of the refrigeration cycle in heating operation using the device, and Fig. 6 is a Mollier diagram of the refrigeration cycle in heating operation using only the solar heat pump device using a small compressor of the heat pump room air conditioner according to Fig. 3. 7 are heating performance charts showing a comparison between the coefficient of performance of the conventional example shown in FIG. 1 and the coefficient of performance of the embodiment shown in FIG. 3. 1...Main compressor, 2...Discharge pipe, 3...Four-way valve, 4...Four-way valve discharge pipe, 5...Radiator, 6...
Capillary tube, 7...Heat absorber, 8...Four-way valve return pipe, 9...Suction pipe, 10...Solar heat collector, 18...Solenoid shut-off valve, 19...Solenoid shut-off valve, 20...Small size Compressor, 20a...branch piping,
21... Injection conduit.

Claims (1)

[Scope of Claims] 1. In a heat pump type room air conditioner, from the discharge pipe of the main compressor, via the four-way valve discharge pipe related to the four-way valve, through the radiator, the expansion device, and the heat absorber, to the four-way valve return pipe related to the four-way valve. At the same time, a suction pipe from the four-way valve to the suction port of the main compressor is separately installed. A solar heat pump device using an in-jet extension, which is then branched into two directions again, and one of the branches is conduited through an electromagnetic on-off valve to an in-jexion port that opens into a cylinder in the middle of the compression stroke of the main compressor. ,
A heat pump type heat pump system, characterized in that the other branched end is connected to the four-way valve discharge pipe via a small compressor with a smaller displacement than the main compressor, and a solar heat pump device using a small compressor is provided. Room air conditioner. 2. The heat pump room air conditioner according to claim 1, wherein a branch pipe provided with a small compressor is provided with an electromagnetic on-off valve on the suction side of the small compressor.