JPH0481708B2 - - 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.

Conventional technology 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.
The heat pump device described in Japanese Patent Application No. 116109/1988, which is our prior invention, will be described below with reference to an embodiment shown in FIG. 2 in which it is applied as a heating/cooling device.

In Fig. 2, 1 is a compressor, 2 is a four-way valve, and 3 is a compressor.
is a load side heat exchanger that acts as a condenser during heating operation, 4 is a throttle device, 5 is a heat source side heat exchanger that acts as an evaporator during heating operation, 6 is an accumulator, and 7 is a throttle that is always used when switching between heating and cooling. This is a check valve group for configuring a refrigerant flow path so that the inlet side of the device 4 is located on the condenser outlet side, and by connecting piping in sequence, a main refrigeration cycle is configured as shown by the solid line arrow during normal heating operation. There is. Next, 8 is a rectifier,
The inside is filled with a filler 9, and a heating source 1 is provided at the bottom. In this embodiment, the heating source 10
consists of a branch discharge gas pipe 12 via a solenoid valve 11, and is connected to the discharge side of the four-way valve 2. Further, the top of the rectifier 8 constitutes a low boiling point refrigerant circulation circuit provided with a cooling source 13, in which a portion of the refrigerant is stored. Here cooling source 11
If the rectifier 8 is to be operated only during low heating load, it is configured to be cooled by a separate cooling device, the inlet or outlet piping of the heat source side heat exchanger 5 that acts as an evaporator, or low-temperature outside air. It's okay. Furthermore, the bottom of the rectifier 8 is connected to a pipe 15 via a solenoid valve 14.
It is connected to the outlet side of the condenser in parallel with the throttle device 4, and is again connected to the bottom of the rectifier 8 by a pipe 16 at a position upstream of the throttle device 4 where there is almost no pressure loss. The solenoid valve 14 is for closing the minute flow of refrigerant through the pipes 15 and 16 when the heating source 10 is stopped.

In a heat pump device having such a configuration,
In particular, the mode of capacity control for the load during heating operation will be explained below. A second chamber containing a non-azeotropic mixed refrigerant
In the heat pump device shown in the figure, if the solenoid valves 11 and 14 are closed during normal heating operation, not only will the heating source 10 not start, but the rectifier 8 will
The main refrigeration cycle is a refrigerant with approximately the same concentration as the non-azeotropic mixed refrigerant sealed in the main refrigeration cycle, and a heating operation is performed.

Next, when the outside temperature rises and low-load heating operation is performed, when the solenoid valves 11 and 14 are opened, the heating source 10 is activated by the high temperature discharge gas of the compressor 1 flowing in via the branch discharge gas pipe 12. Of the liquid refrigerant stored at the bottom of the rectifier 8, mainly the low boiling point refrigerant is evaporated and charged with the liquid mixed refrigerant flowing down from the low boiling point refrigerant circulation circuit via the cooling source 13 at the top. Countercurrent contact occurs through the material 9, and the low-boiling refrigerant is concentrated at the top of the rectifier 8, and the high-boiling refrigerant is concentrated at the bottom. Here, the solenoid valve 14 is open, and the pipe 1
The main refrigeration cycle together with 5 and 16 constitutes a high boiling point refrigerant circulation circuit at the bottom of the rectifier 8,
The mixed refrigerant in the main refrigeration cycle flows into the bottom of the rectifier 8 via the solenoid valve 14, and conversely, the high boiling point refrigerant concentrated at the bottom is attracted by the refrigerant circulating in the main refrigeration cycle to a low pressure. Due to the outflow, the refrigerant circulating through the main refrigeration cycle has a progressively increasing concentration of high boiling refrigerant. This mode of action is indicated by the dashed arrow in FIG. Therefore, as the amount of high boiling point components increases, the gas specific volume increases.
This reduces the amount of refrigerant circulated in the engine and reduces the capacity.

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. The rectifying action circulates the low boiling point refrigerant in the refrigerant supplied from the main refrigeration cycle through the pipe 15 to the top of the rectifier 8, and the high boiling point refrigerant concentrated at the bottom is exchanged with the refrigerant in the main refrigeration cycle through the pipe 16. However, since the branch flow rate of the pipes 15 and 16 is basically determined by the pipe resistance, it is greatly influenced by the opening degree adjustment of the throttling device 4 in the main refrigeration cycle, and the desired separation performance cannot be obtained. This may cause problems such as no

Also, depending on how the pipes 15 and 16 are connected to the main refrigeration cycle, the high boiling point refrigerant circulated at the bottom of the rectifier 8 is not attracted, and no new refrigerant is supplied, resulting in a rectification effect. It had some problems such as stopping.

The present invention relates to an improvement of a refrigeration cycle in a heat pump device using such a non-azeotropic mixed refrigerant in order to increase the reliability of the rectification action and improve the controllability of the composition.

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 the lower part of the separator bypasses the main throttling device of the main cycle circuit. The condenser outlet is connected to the evaporator inlet through a throttling device, and a cooler/cooler is installed at the top of the separator.
A circulation circuit is constructed in which reservoirs are connected to achieve reliable rectification.

Effect By adopting such a configuration on the refrigeration cycle, the branched flow rate to the separator side is almost determined by the piping resistance of the throttling device interposed between the separator and the evaporator inlet, so the main cycle circuit Even by adjusting the opening of the main throttling device, a reliable rectification effect is achieved without large fluctuations, and the refrigerant concentrated in the separator directly flows through the throttling device to the evaporator inlet, which becomes the low-pressure pipe. This ensures rapid compositional variation.

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, a compressor 31, a four-way valve 32,
The load side heat exchanger 33, the main throttle device 34, the heat source side heat exchanger 35, etc. are connected in a circular manner to form a main cycle circuit. Also, as a bypass of the main throttle device 34, a sub-cycle circuit is constructed in which throttle devices 36, 37, check valves 38, 39, a separator 41 filled with a filler 40, a reservoir 42, etc. are connected. A heater 43 is disposed at the top, and a cooler 44 is disposed at the top. In this embodiment, the discharge gas from the compressor 31 is used as a heat source for heating the heater 43 and is led from a bypass circuit 46 via a solenoid valve 45. It is structured accordingly. In addition, as a cooling heat source for the cooler 44,
The suction gas of the compressor 31 may be used (not shown), or the cooling may be performed using low-temperature outside air.
A non-azeotropic mixed refrigerant is sealed inside the refrigeration cycle.

The mode of operation of such a heat pump device will be explained with a focus on heating operation. In order to obtain high capacity, it is known that a large amount of low boiling point refrigerant is circulated in the main cycle circuit as a refrigerant composition. 4
By closing 5, a mixed refrigerant having almost the same composition as the enclosed non-azeotropic mixed refrigerant is mainly transferred to the compressor 31 → four-way valve 32 → load side heat exchanger 33 → main throttle device 34 → heat source side heat exchange It circulates in the order of container 35 → four-way valve 32 → compressor 31, and a part bypasses from load-side heat exchanger 33, which serves as a condenser, and circulates through check valve 38 →
The surplus refrigerant circulates from the lower part of the separator 41 to the throttling device 37 to the heat source side heat exchanger 35 and is stored in the reservoir 42, so the mixed refrigerant containing the low boiling point refrigerant absorbs heat from the load side, which becomes the condenser. It becomes possible to output high heating capacity in the exchanger 33.

On the other hand, when reducing the capacity, when the solenoid valve 45 is opened, a part of the gas discharged from the compressor 31 flows through the heater 43 via the bypass circuit 46, 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 41, and rises in the cooler 4.
4, the refrigerant is condensed and liquefied, mixed with the surplus refrigerant in the reservoir 42, and a part of the refrigerant flows down and refluxes in the separator 41. Here, inside the separator 41, gas-liquid contact between the ascending gas refrigerant and the descending liquid refrigerant is promoted by the filler 40 in a state of minute flow velocity, and the low boiling point refrigerant is The concentrated high-boiling refrigerant flows through the throttle device 37 connected to the lower part of the separator 41 to the heat source side heat exchanger 35, which is a low-pressure pipe, and the main cycle circuit is closed due to the increased concentration of the high-boiling refrigerant. Therefore, it becomes possible to realize low heating capacity in the load side heat exchanger 33.

During cooling operation, by switching the four-way valve 32, the main flow is as follows: compressor 31 → four-way valve 32 → heat source side heat exchanger 35 → main throttling device 34 → load side heat exchanger 3
It circulates in the order of 3 → four-way valve 32 → compressor 31, and part of it bypasses from the heat source side heat exchanger 35, which serves as a condenser, and goes through the check valve 39 → the lower part of the separator 41 → the throttle device 3.
6→Load-side heat exchanger 33 and the means for varying the refrigerant composition by rectification are the same as in the heating operation. That is, the throttle devices 36, 37 and the check valve 3
8 and 39 are for supplying high pressure liquid refrigerant from a heat exchanger that positions the separator 41 at high pressure and acting as a condenser into the separator 41 and promoting vaporization in the heater 43 in this embodiment. If necessary, the separator 41 connected via another throttling device may be located at an intermediate pressure, and the low boiling point refrigerant may be vaporized by the pressure reduction of the throttling device.

In this embodiment, when a rectification effect is used as a composition variable means of a heat pump device, when a low boiling point refrigerant is concentrated in a reservoir placed at the upper part of a separator,
In order to increase the reliability of the rectifying action in the separator and suppress fluctuations in the branch flow rate to the separator side without adjusting the opening of the main throttle device in the main cycle circuit, the main throttle device is bypassed for condensation. The separator connected to the outlet of the evaporator is again connected to the inlet of the evaporator via a throttling device, and of course it is within the scope of the present invention to combine it with other sources of heating or cooling.

Effects of the Invention The heat pump device of the present invention uses a non-azeotropic mixed refrigerant and bypasses the main throttling device of the main cycle circuit, and connects the condenser outlet and the evaporator inlet via the throttling device. The sub-cycle circuit consists of a cooler, a storage device, etc. installed in the circulation circuit at the top of the separator, and the low boiling point refrigerant is concentrated in the storage device at the top of the separator by rectification in the separator placed at a high pressure or intermediate pressure position. By doing so, the composition of the refrigerant in the main cycle circuit can be varied, thereby increasing the controllability of the composition of the main cycle circuit, thereby making 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. 31...Compressor, 33...Load side heat exchanger, 3
4... Main throttling device, 35... Heat source side heat exchanger, 3
6, 37... throttle device, 38, 39... check valve,
41... Separator, 42... Reservoir.

Claims (1)

[Claims] 1 At least a compressor, a load-side heat exchanger, a main throttle device, and a heat source-side heat exchanger are connected in a ring to form a main cycle circuit, and the main cycle circuit is connected to the outlet of a heat exchanger that bypasses the main throttle device and becomes a condenser. The lower part of the separated separator is connected again to the inlet of the heat exchanger, which becomes an evaporator, via a throttle device, and a circulation circuit is constructed in which a cooler and a storage device are connected to the upper part of the separator, and the non-azeotropic mixed refrigerant is A heat pump device characterized by being enclosed.