JPS5913571Y2 - air conditioner - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a highly efficient air conditioner using an ejector.

Figure 1 is a refrigerant circuit diagram showing a conventional air conditioner, where 1 is a compressor, 2 is a first heat exchanger (used as a refrigerant condenser in the figure), 3 is an ejector, and 4 is a second heat exchanger. Heat exchanger,
5 is a gas-liquid separator, which are connected in a ring to form a refrigeration cycle.

Further, the refrigerant liquid separated by the gas-liquid separator 5 passes through a first pressure reducing device 6 (for example, a capillary tube), passes through a third heat exchanger 7, and becomes a pipe to be sucked into the suction side of the ejector 3. There is.

Figure 2 shows the operating points of the refrigeration cycle in Figure 1 drawn on a Mollier diagram.
The state of the refrigerant at -g corresponds to a-g on the Mollier diagram in FIG.

In the conventional device having the above configuration, the refrigerant gas (state point b) compressed by the compressor 1 and becomes high temperature and high pressure.
After being cooled and condensed and liquefied in the first heat exchanger 2 (state point C), it enters the ejector 3.

Here, the pressure is reduced to a low pressure ps, and the refrigerant coming from the first heat exchanger 2 moves from state point C to d//, but at this time, it evaporates from the suction side of the ejector 3 in the third heat exchanger 7 and becomes gas. In order to suck the gas refrigerant at the state point d', the state point d'
and d // and reaches a state point d determined by the refrigerant flow rate from the first heat exchanger 2 and the refrigerant flow rate from the third heat exchanger 7, after which it evaporates in the second heat exchanger 4 and reaches a state point e. leading to.

After the refrigerant leaves the second heat exchanger 4, it is separated into the liquid refrigerant at the state point f and the gas refrigerant at the state point e in the gas-liquid separator 5, and the liquid refrigerant at the state point f flowing due to the suction effect of the ejector 3 is , passes through the first pressure reducing device 6, is depressurized to state point g, and goes to the third heat exchanger 7.

Here, it is evaporated at a pressure ps/ lower than the suction pressure ps of the second heat exchanger 4 or the compressor 1, and is sucked into the ejector 3 as a saturated gas indicated by state point d'.

In such a refrigeration cycle, when used as a heat pump, for example, the evaporation pressure pS' of the third heat exchanger 7 can be lower than the suction pressure ps of the compressor 1, and heat can be extracted even from a low heat source temperature (for example, outside air). can be pumped up.

Also, when used for cooling, the third heat exchanger 7 can evaporate at a lower evaporation pressure pS'.
For example, the objective was to have the effect that a large temperature difference between the refrigerant and water, air, etc. can be achieved, and that the evaporator, which is a combination of the second heat exchanger 4 and the third heat exchanger 7, can be made smaller.

However, the above configuration has the disadvantage that it can only be used for cooling or heating.

This invention was made in view of these points, and aims to provide an air conditioner that is efficient in both cooling and heating operations.

Fig. 3 shows an example of this invention.
7 to 7 are exactly the same as the conventional device shown in FIG. 1 above.

3a and 3b are first and second ejectors, 8 is a four-way switching valve for switching between cooling and heating operations, 9a and 9b are first and second check valves, and nozzle inlet piping of ejectors 3a and 3b. attached to the section.

Reference numerals 10 and 11 designate first and second on-off valves for switching the flow direction of the refrigerant, and 12 represents a fourth heat exchanger paired with the first heat exchanger 2.

In these components, the refrigerant coming out of the liquid part of the gas-liquid separator 5 is divided into two directions after passing through the first pressure reducing device 6.
One is the refrigerant that goes to the fourth heat exchanger 12 after exiting the on-off valve 11, and the refrigerant that goes to the nozzle inlet of the second ejector 3b via the check valve 9b, and the other becomes the third heat exchanger after exiting the on-off valve 10. The circuit is configured such that the refrigerant goes to the exchanger 7 and the refrigerant goes to the nozzle inlet of the first ejector 3a via the check valve 9a.

The discharge port of the first ejector 3a is connected to the first heat exchanger 2, the suction port is connected to the fourth heat exchanger 12, respectively, and the discharge port of the second ejector 3b is connected to the second heat exchanger 4. , the suction ports are connected to the third heat exchanger 7 through piping, respectively.

In the air conditioner configured as described above, for example, a pair of first heat exchanger 2 and fourth heat exchanger 12 are used.
When used as an indoor heat exchanger and the second heat exchanger 4 and the third heat exchanger 7 as outdoor heat exchangers, the refrigerant circuit becomes as shown in FIG. 3 during heating operation, and the on-off valve 10 is open, and the on-off valve 11 is closed.

At this time, the refrigerant gas that has been compressed by the compressor 1 and has become high temperature and high pressure goes to the first heat exchanger 2, where it radiates heat and is partially condensed, and then flows from the discharge port of the first ejector 3a to the suction port. The flow goes to the fourth heat exchanger 12, where it further radiates heat and condenses, and after being liquefied, it passes through the check valve 9b and enters the nozzle part of the second ejector 3b, where it is ejected and depressurized to produce the second heat. Go to exchange 4.

The gas-liquid mixed refrigerant ejected at this time is transferred to the third heat exchanger 7.
The evaporated gas is sucked from the suction port of the second ejector 3b and goes to the second heat exchanger 4, where it is partially evaporated, and the remaining part passes through the light switching valve 8 as a liquid and is aired. Go to liquid separator 5.

The gas-liquid separator 5 separates the refrigerant gas (that is, the refrigerant evaporated in the second heat exchanger 4 and the third heat exchanger 7) into a liquid, the gas is sucked into the compressor 1, and the liquid is passed from the liquid outlet pipe. After passing through the first pressure reducing device 6 and being reduced to the pressure that is sucked by the second ejector 3b, it passes through the on-off valve 10 to the third heat exchanger 7, where it evaporates and becomes gas, which is sucked into the second ejector 3b. Ru.

At this time, the first ejector 3a merely constitutes a refrigerant passage, and the indoor space is heated by heat radiation from the first heat exchanger 2 and the fourth heat exchanger 12, and the third heat exchanger 7 heats the room outside. Heat can be pumped up from, for example, outside air at a pressure lower than the suction pressure of the compressor 1, and efficient heating operation can be performed.

On the other hand, during cooling operation, the piping system is as shown in Figure 4.
The on-off valve 10 is closed, and the on-off valve 11 is open.

At this time, the refrigerant gas compressed by the compressor 1 to a high temperature and high pressure passes through the four-way switching valve 8 and passes through the second heat exchanger 4 located on the outdoor side.
After the heat is radiated and partially condensed, it is further transferred from the discharge port of the second ejector 3b to the third heat exchanger 7 via the suction port.
After further dissipating heat and condensing and liquefying, it enters the first ejector 3a via the check valve 9a, and is ejected from the nozzle opening to become low pressure.

At this time, the gas-liquid mixed refrigerant ejected from the nozzle port evaporates in the fourth heat exchanger 12, sucks the refrigerant gas in the second ejector 3b, goes to the first heat exchanger 2 on the indoor side, and partially evaporates. The mixture of gas and liquid goes from the four-way switching valve 8 to the gas-liquid separator 5.

Here, the refrigerant is separated into gas and liquid, the gas refrigerant (the refrigerant evaporated in the first heat exchanger 2 and the fourth heat exchanger 12) returns to the compressor 1, and the liquid refrigerant passes through the first pressure reducing device 6. After the pressure is reduced to the suction pressure of the second ejector 3b, it goes from the on-off valve 11 to the fourth heat exchanger 12, where it evaporates and becomes a gas.
It is sucked into the ejector 3a.

(At this time, the pressure between the on-off valve 11 and the check valve 9b is low, and the pressure between the check valve 9b and the second ejector 3b is high, so the refrigerant flows from the on-off valve 11 to the check valve 9b. It does not flow through to the second ejector 3b.

) At this time, the second ejector 3b merely constitutes a flow path for the refrigerant, and the interior of the room is cooled by evaporation of the refrigerant within the first and fourth heat exchangers 2 and 12.

In addition, in the fourth heat exchanger 12, the refrigerant evaporates at a pressure lower than the suction pressure of the compressor 1. For example, the suction pressure of the compressor 1 can be set higher by this amount, which allows efficient operation. can be done.

Note that in the above embodiment, the first. Second ejector 3
Both the inlets of a and 3b are supercooled refrigerant liquid, but in order to increase the amount of refrigerant gas sucked from the suction side of each ejector and improve efficiency,
It is also conceivable to insert a pressure reducing device (for example, a capillary tube) between each of the check valves 9a, 9b and the refrigerant at the inlet of each ejector to make the state of the refrigerant a gas-liquid mixture.

Moreover, the first heat exchanger 2 and the fourth heat exchanger 12 and the second heat exchanger 4 and the third heat exchanger 7 can be integrated into each other, and in this case, the first heat exchanger 2 and the fourth heat exchanger 12 can be integrated into each other. If a plate-fin tube type heat exchanger 13 that exchanges heat with air is used as shown in FIG. 5, it is possible to share the fins 14.

Furthermore, at this time, the first heat exchanger 2 and the fourth heat exchanger placed on the outdoor side
Regarding the heat exchanger 12, it is preferable to place the fourth heat exchanger 12, in which the refrigerant evaporates at a lower evaporation temperature, on the air outlet side, as in the case of heating.

Regarding these arrangement relationships, the example in which the heat medium is air has been described above, but the third and fourth heat exchangers 7,
, 12 as the second . It is preferable to provide it on the heat medium outlet side with respect to the first heat exchanger 4°2.

Although the liquid receiver, accumulator, strainer, dryer, etc. are omitted in the refrigeration cycle shown in FIGS. 3 and 4, the circuit may include these if necessary.

As described above, in this invention, the heat exchanger is divided into two for both the indoor and outdoor sides, and the first and second ejectors are used, and these heat exchangers and ejectors are connected via a valve. This has the effect that efficient operation can be performed during both cooling and heating operations.

[Brief explanation of the drawing]

Fig. 1 is a refrigerant circuit diagram of a conventional air conditioner, Fig. 2 is a drawing of the operating points of the refrigeration cycle shown in Fig. 1 on a Mollier diagram, and Fig. 3 shows an embodiment of this invention. Refrigerant circuit diagram, Figure 4 is a refrigerant circuit diagram when switching between cooling and heating in Figure 3,
FIG. 5 is a perspective view showing an example of an outdoor or indoor heat exchanger. In the figure, 1 is a compressor, 2 is a first heat exchanger, 3 a, 3
b is the first and second ejector, 4 is the second heat exchanger, 5
is a gas-liquid separator, 6 is a first pressure reducing device, 7 is a third heat exchanger, 8 is a four-way switching valve, 9 a and 9 b are first and second check valves, 10.11 is the first , a second on-off valve, 12 a fourth heat exchanger, and 14 a fin. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] An air conditioner in which a compressor, first and second heat exchangers, and a gas-liquid separator are connected in an annular manner, and in which cooling and heating can be switched by a four-way switching valve, configured as a pair with the second heat exchanger. a fourth heat exchanger configured as a pair with the first heat exchanger, and first and second ejectors, and a liquid outlet portion of the gas-liquid separator. The first pressure reducing device (
For example, the inlet of the first ejector is connected to the inlet of the first ejector, one of the outlets of the first pressure reducing device passes through the first on-off valve, one is connected to the nozzle inlet of the first ejector from the first check valve, and the other is connected to the nozzle inlet of the first ejector. The other outlet of the first pressure reducing device is connected to the suction part of the second ejector through the heat exchanger No. 3, and the other outlet of the first pressure reducing device is connected to the suction part of the second ejector through the second check valve. The nozzle inlet and the other are connected to the suction part of the first ejector via the fourth heat exchanger, and the discharge port of the first ejector, the first heat exchanger, and the discharge port of the second ejector. An air conditioner characterized in that the air conditioner is connected to a second heat exchanger.