JPH0360031B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a refrigeration cycle for a heat pump device using a non-azeotropic mixed refrigerant.

BACKGROUND ART A heat pump device using a non-azeotropic mixed refrigerant can control capacity and improve performance by varying the composition of the refrigerant circulating inside the refrigeration cycle.

We have proposed a comparison sequence as shown in FIG. 2 as a prior invention. FIG. 2 shows an embodiment in which a heat pump device using a non-azeotropic mixed refrigerant is applied as an air-conditioning device.
The main throttle device 4, the heat source side heat exchanger 5, etc. are connected in a ring to form a main cycle circuit. In addition, as a bypass of the main throttle device 4, a sub-cycle circuit is constructed in which throttle devices 6, 7, check valves 8, 9, a separator 11 filled with a filler 10, a reservoir 12, etc. are connected. A heater 13 is disposed at the top, and a cooler 14 is disposed at the top.
5 from a bypass circuit 16. In addition, as a cooling heat source for the cooler 14, the suction gas of the compressor 1 may be used (not shown), or the cooling may be performed using low-temperature outside air. Refrigerant is sealed.

Explaining the mode of operation of such a heat pump device, focusing on heating operation, it is known that in order to obtain high capacity, a large amount of low boiling point refrigerant is circulated as a refrigerant composition circulating in the main cycle circuit, and solenoid valve 1
By closing 5, a mixed refrigerant having almost the same composition as the enclosed non-azeotropic mixed refrigerant flows mainly through the compressor 1 → four-way valve 2 → load-side heat exchanger 3 → main throttle device 4
→ Heat source side heat exchanger 5 → Four-way valve 2 → Compressor 1 It circulates in this order, some of it bypasses from load side heat exchanger 3, and checks valve 8 → Separator 11 lower part → Main throttling device 7 →
Surplus refrigerant circulates with the heat source side heat exchanger 5 and is stored in the reservoir 12
Therefore, the mixed refrigerant containing the low boiling point refrigerant allows the load-side heat exchanger 3 to output high heating capacity.

On the other hand, when reducing the capacity, when the solenoid valve 15 is opened, part of the gas discharged from the compressor 1 flows through the heater 13 via the bypass circuit 16, so that it is circulated through the sub-cycle circuit. This will heat some of the mixed refrigerant. At this time, due to the nature of the non-azeotropic mixed refrigerant, the more volatile low-boiling refrigerant is vaporized, rises in the separator 11, and rises in the cooler 14.
The refrigerant is condensed and liquefied, mixed with surplus refrigerant in the reservoir 12, and a part of the refrigerant flows down and refluxes in the separator 11.
Here, inside the separator 11, the gas-liquid contact between the rising gas refrigerant and the falling liquid refrigerant is promoted by the filler 10 at a very small flow rate, and the low-boiling point refrigerant is mixed in the reservoir 12 due to the so-called rectification effect. In the main cycle circuit which is concentrated and connected to the lower part of the separator 11, the concentration of the high boiling point refrigerant increases, thereby making it possible to realize a low heating capacity in the load side heat exchanger 3.

During heating operation, by switching the four-way valve 2, the main flow is compressor 1 → four-way valve 2 → heat source side heat exchanger 5 → main throttling device 4 → load-side heat exchanger 3 → four-way valve 2
→ It circulates in the order of the compressor 1, and a part bypasses the heat source side heat exchanger 5 and circulates through the check valve 9 → the lower part of the separator 11 → the expansion device 6 → the load side heat exchanger 3, and the rectification effect The means for varying the refrigerant composition is the same as during heating operation. That is, the throttle devices 6, 7 and the check valves 8, 9 supply high-pressure liquid refrigerant from the heat exchanger, which positions the separator 11 at high pressure and acts as a condenser, into the separator 11 and heat it. This is to promote vaporization in the vessel 13, and the separator 11 may be located at an intermediate pressure depending on the case.

Problems to be Solved by the Invention Although it is basically possible to change the composition of the refrigerant in the heat pump device as in the above comparative example, the following problems occur, for example. For example, when starting a heating operation, a high heating capacity is required, so the solenoid valve 15 is closed, but since the bypass circuit 16 is cooled by the ambient temperature, a portion of the gas discharged from the compressor 1 flows into the bypass circuit 16. The refrigerant condenses and accumulates in the heater 13, and at this time a rectifying action naturally occurs in the heater 13 to radiate heat, resulting in problems such as the refrigerant having the same composition as the desired sealed refrigerant composition not being circulated.

Furthermore, even if the bypass circuit 16 is full of liquid and the accumulation has stopped, for example, the cooler 1
When 4 is configured with outside air cooling, the high-pressure or intermediate-pressure refrigerant that bypasses the heat exchanger that acts as a condenser and flows into the subcycle circuit is still at a relatively high temperature compared to the outside air, and the gas components If the refrigerant contains , not only will a rectification effect occur naturally, but also there will be problems such as the composition of the refrigerant circulating in the main cycle circuit will not be stable due to fluctuations in the outside air that serves as the cooling source.

In a heat pump device using such a non-azeotropic mixed refrigerant, the present invention increases the reliability especially when stopping the rectification action, and improves the refrigerant composition so that the refrigerant composition circulating in the main cycle becomes equal to the enclosed refrigerant composition. It concerns cycle improvements.

Means for Solving the Problems The heat pump device according to the present invention uses a separator that performs a rectifying action as a means for varying the composition of a non-azeotropic mixed refrigerant, and when stopping the rectifying action, the heat pump device according to the present invention By connecting the separator to the low-pressure piping of the reservoir and creating a forced flow inside the separator, the rectification operation can be stopped reliably.

Effect By adopting such a configuration on the refrigeration cycle, when a forced upward flow is realized, the flow of the falling liquid refrigerant is obstructed, and when a forced downward flow is realized, the flow of the rising gas refrigerant is obstructed. This prevents gas-liquid contact at a minute flow rate inside the separator, thereby preventing natural rectification and ensuring a desired refrigerant composition.

Embodiment An embodiment of the heat pump device according to the present invention will be explained using the embodiment shown in FIG. 1, which is applied to an air-conditioning device. In FIG. 1, numerals 1 to 14 are the same components as in the conventional example shown in FIG. The distinctive feature in FIG. 1 is that the separator 11 in the lower part of the reservoir 12
A bypass circuit 18 of the auxiliary cycle is constructed from a portion connected to the upper part of the auxiliary cycle via a solenoid valve 17. In this embodiment, although the heater 13 and the cooler 14 are not shown, they are configured so that the discharge gas and suction gas of the compressor 1 are directly guided, and the refrigerant always flows regardless of the presence or absence of rectification. It is something that exists.

In such a heat pump device, when increasing the concentration of high boiling point refrigerant in the main cycle circuit by exerting a rectifying action, the same mode of action as shown in FIG. 2 is realized by closing the solenoid valve 17. It is.

A feature of the present invention is that when the rectifying action is stopped during heating operation, for example, when the solenoid valve 17 in the bypass circuit 18 is opened, the upper part of the separator 11 and the reservoir 12 in the sub-cycle circuit are bypassed. Since it is directly connected to the low-pressure heat source side heat exchanger 5 through the circuit 18, the flow of refrigerant in the auxiliary cycle circuit is mainly from the check valve 8 → separator 11 → reservoir 12 →
It flows in the order of bypass circuit 18→throttle device 7→heat source side heat exchanger 5, and in the separator 11 it flows in the order of high flow velocity state 5, and in the separator 11, an upward flow with a high flow velocity state is realized. be. Therefore, even if the refrigerant is heated by the heater 13 and constantly cooled by the cooler 14, the flow of the liquid refrigerant flowing down and refluxed from the reservoir 12 into the separator 11 is obstructed, stopping the natural rectifying action. This makes it possible. In addition, by configuring the piping resistance of the bypass circuit 18 to be particularly small, the flow rate of refrigerant bypassed from the load-side heat exchanger 3 to the auxiliary cycle circuit also increases slightly, which reduces the heating required during rectification. The small heating amount of the vessel 13 makes it impossible to vaporize the low boiling point refrigerant.

Next, if you want to stop the rectifying action during cooling operation, switch the four-way valve 2 and open the solenoid valve 17.
The flow of refrigerant in the auxiliary cycle circuit is mainly caused by the check valve 9→
It flows in the order of bypass circuit 18 → reservoir 12 → separator 11 → throttling device 6 → load-side heat exchanger 3, and in the separator 11, a downward flow at a high flow rate is realized. Therefore, in this case, even if heater 13
Even if the low boiling point refrigerant is vaporized and tries to rise in the separator 11, its flow is blocked, making it possible to reliably stop the rectification action.

In this embodiment, a case has been described in which a low boiling point refrigerant is concentrated in a reservoir placed in the upper part of a separator when a rectification effect is used as a means for varying the composition of a heat pump device, but the present invention is not limited to this. , for example, placing a reservoir at the bottom of the separator,
The same is true when a refrigerant cycle (not shown) is configured to condense a high-boiling refrigerant in the reservoir, and the key is to reliably stop the rectification effect achieved at the minute flow rate in the separator. Therefore, rather than stopping the heating source or cooling source, this is accomplished by achieving a high flow velocity state in the separator.
For example, if the electromagnetic valve 17 in Fig. 1 is configured with a downward-facing check valve, it is possible to stop the rectifying action during heating operation and activate the rectifying action only during cooling operation, and of course stop the heating source and cooling operation. It is within the scope of the present invention to combine with.

Furthermore, as explained in the prior art section, if the check valves 8 and 9 of FIG. 1 are omitted, the separator 11 can be located at an intermediate pressure. At this time, the refrigerant flows into the separator 11 via the throttling device 6 during heating operation and through the throttling device 7 during cooling operation while generating the gas necessary for rectification, so the heater 13 can be omitted. can.

Effects of the Invention The heat pump device according to the present invention uses a non-azeotropic mixed refrigerant and uses a rectifying action in the separator placed at a high pressure or intermediate pressure position in the auxiliary cycle circuit to store a low boiling point The refrigerant composition in the main cycle circuit is varied by concentrating the refrigerant, and the flow of the refrigerant can be selected by placing a solenoid valve in the bypass circuit connecting the vicinity of the reservoir and the low-pressure piping. By doing so, when the solenoid valve is opened, a high-speed flow state is formed inside the separator, and the rectification action can be reliably stopped regardless of the presence or absence of a heating source or cooling source, and the composition of the main cycle circuit can be This improves controllability and, in turn, makes it possible to guarantee capacity control and performance improvement.

[Brief explanation of drawings]

FIG. 1 is a principle diagram of a heat pump device according to an embodiment of the present invention, and FIG. 2 is a principle diagram of a comparative example of a heat pump device using a non-azeotropic mixed refrigerant. 1...Compressor, 3...Load side heat exchanger, 4...
Main throttling device, 5... Heat source side heat exchanger, 11... Separator, 12... Reservoir, 13... Heater, 14...
...Cooler, 17...Solenoid valve, 18...Bypass circuit.

Claims (1)

[Claims] 1 At least a compressor, a load-side heat exchanger, a main throttling device, and a heat source-side heat exchanger are connected in a ring to form a main cycle circuit, the main throttling device is bypassed, and a separator is provided above the separator. A heat pump device comprising a sub-cycle circuit consisting of a cooler and a storage device, further comprising a bypass circuit connecting the storage device to a low-pressure pipe and a valve, and enclosing a non-azeotropic mixed refrigerant.