JP2730648B2 - Air conditioning - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a refrigerant cycle of a cooling and heating device.

2. Description of the Related Art Conventionally, as shown in, for example, Japanese Patent Application Laid-Open No. Sho 62-238952, a refrigerant cycle of a cooling and heating device separated into a heat source side refrigerant cycle and a use side refrigerant cycle has been configured as shown in FIG. In FIG. 3, 1 is a compressor, 2 is a pilot type heat source side four-way valve operated by a pressure difference, 3 is a heat source side heat exchanger, 4 is a decompression device for cooling, 5 is a decompression device for heating, and 6 is a heating device. Check valve for closing the pressure reducing device 4 for cooling during cooling, 7 is a check valve for closing the pressure reducing device 5 for cooling during heating, 8 is a first auxiliary heat exchanger, which is connected in a ring shape to cool the heat source side. Cycle (X)
Is formed. Reference numeral 9 denotes a second auxiliary heat exchanger which is integrally formed so as to exchange heat with the first auxiliary heat exchanger 8. Reference numeral 10 denotes a refrigerant amount adjustment tank for adjusting the amount of refrigerant during cooling and during heating, and stores excess refrigerant during cooling. 11
Has a reversible characteristic in which the refrigerant flows in opposite directions during cooling and during heating, and these are accommodated in the heat source side unit a. Reference numeral 12 denotes a use side heat exchanger which is housed in the use side unit b and connected to the heat source side unit a by connection pipes c and c '.
Is connected to The second auxiliary heat exchanger 9, the refrigerant amount adjusting tank 10, the refrigerant transport device 11, the use side heat exchanger 12, and the connection pipe f are connected in a ring to form a use side refrigerant cycle (Y). The use-side refrigerant cycle (Y) and the heat-source-side refrigerant cycle (X) are filled with refrigerant having the same or similar condensation / evaporation characteristics.

The operation of the cooling / heating device configured as described above will be described.

In the cooling operation, the refrigerant cycle is indicated by a solid line arrow in the figure. In the heat source side refrigerant cycle, the high-temperature and high-pressure gas from the compressor 1 passes through the heat source side four-way valve 2 and radiates heat in the heat source side heat exchanger 3 to condense and liquefy. The pressure is reduced by the cooling expansion valve 4 through the valve 6 and
It evaporates in the auxiliary heat exchanger 8 and circulates through the heat source side four-way valve 2 to the compressor 1.

This state will be described with reference to a Mollier diagram shown in FIG. 4, which shows a general refrigeration cycle ABCD, where AB is compression in the compressor 1, BC is heat radiation in the heat source side heat exchanger 3, and CD is Represents the pressure reduction at the cooling expansion valve 4, and DA represents the evaporation at the first auxiliary heat exchanger 8.

At this time, the second auxiliary heat exchanger 9 and the first auxiliary heat exchanger 8 in the use-side refrigerant cycle exchange heat (FIG. 3E-F), and the gas refrigerant in the use-side refrigerant cycle is cooled to dryness. Is reduced, is sent to the refrigerant transfer device 11 through the refrigerant amount adjustment tank 10, and is sent to the use side heat exchanger 12 through the connection pipe c by the refrigerant transfer device 11 (FIG. 3F-G). After cooling, heat is absorbed and evaporated (GE in FIG. 3), the dryness increases, and the heat is circulated to the second auxiliary heat exchanger 9 through the connection pipe c ′.

On the other hand, during the heating operation, the refrigerant cycle is indicated by a broken line arrow in the drawing, and in the heat source side refrigerant cycle (X), the high temperature and high pressure refrigerant from the compressor 1 is sent from the heat source side four-way valve 2 to the first auxiliary heat exchanger 8. The heat is condensed and liquefied, and the pressure is reduced from the check valve 7 by the heating pressure reducing device 5. The heat is absorbed and evaporated by the heat source side heat exchanger 3 and circulated to the compressor 1 through the heat source side four-way valve 2. At this time, the second auxiliary heat exchanger 9 and the first auxiliary heat exchanger 8 of the use side refrigerant cycle (Y) exchange heat, and the refrigerant in the use side refrigerant cycle (Y) is heated to increase the dryness ( Fig. 4H-
I), is sent to the use side heat exchanger 12 through the connection pipe c ', and is heated and radiated to reduce the dryness (FIG. 4J-G).
The refrigerant is sent to the refrigerant transfer device 11 through the connection pipe c, and circulates from the refrigerant amount adjustment tank 10 to the second auxiliary heat exchanger 9 (FIG. 4, JH).

However, in the conventional configuration, the state of the refrigerant sucked into the refrigerant transfer device 11 is a state where the degree of dryness is always small, such as point F or J on the Mollier diagram as shown in FIG. It is unlikely that this is a so-called two-phase flow of gas-liquid mixing, in which liquid and wet gas flow intermittently. Furthermore, the situation is not always constant including load fluctuation, startup, etc., for example, the state of the wet gas continues for a long time, and the refrigerant conveyance device 11 may cause large damage such as poor lubrication due to liquid refrigerant. Become.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a cooling and heating device for smoothly transferring a two-phase flow refrigerant.

Means for Solving the Problems In order to solve the above problems, the air conditioner of the present invention is provided with a gas-liquid separator on the suction side of a refrigerant transport device, and further cooled by a heat source side refrigerant cycle. A vessel is provided in a heat exchange relationship with the gas-liquid separator.

Operation According to the present invention, the refrigerant sucked into the refrigerant transport device is once separated into a gas phase (wet gas) and a liquid phase by a gas-liquid separator, and then the separated gas phase is cooled by a cooler. The present invention forcibly promotes liquefaction, sends the refrigerant to a refrigerant transport device, prevents gas suction for a long time, eliminates insufficient lubrication due to liquid refrigerant, and prevents accidents in the refrigerant transport device.

Embodiment Hereinafter, a cooling and heating apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention, and the same parts as those in the conventional example (FIG. 2) are denoted by the same reference numerals, and description thereof will be omitted.

Reference numeral 14 denotes a gas-liquid separator having an inlet 14a and a liquid outlet 14b. Reference numeral 15 denotes a cooler disposed in the gas layer (upper part) in the gas-liquid separator 14, which is cooled by the refrigerant of the heat source side refrigerant cycle (X). That is, one end is connected to the upstream of the heating and cooling decompression devices 5 and 4 of the heat source side refrigerant cycle (X) via the dedicated decompressors 16 and 17 and the solenoid valves 18 and 19, and the other end is the suction of the compressor 1. Connected to the side.

According to such a configuration, in the cooling operation, the refrigerant in the two-phase flow state (point L in FIG. 2) that has been heat-exchanged (KL in FIG. 2) in the second auxiliary heat exchanger 9 is supplied to the refrigerant amount adjusting tank 10. The liquid enters the gas-liquid separator 14 through the use side four-way valve 13 and is once separated into a liquid and a humid gas. The liquid (point M in FIG. 2) is cooled simultaneously with gas cooling to reach point 0, The heat exchanger 11 is pressurized and heat-exchanges in the use-side heat exchanger 12 (P-K in FIG. 2). On the other hand, the gas in the gas-liquid separator 14 is a heat source side refrigerant cycle (X).
The liquefaction of the cooler is promoted by the cooler 15 of FIG. FIG. 2 VW shows the cooling of the cooler 15.

In heating, Q → R → R → S → S in FIG.
The refrigerant circulates in the order of → T → U, and the liquid (point T) also separated by the gas-liquid separator 14 is cooled to reach the point U, sent to the refrigerant transport device 11, and gas-cooled by the cooler 15. Is liquefied.

The evaporating temperature of the cooler at the time of heating does not become lower than that at the time of cooling, and is adjusted by adjusting the decompressor 17 to obtain V '
The temperature may be increased as in W '.

Effect of the Invention According to the above configuration, the present invention provides a gas-liquid separator on the suction side of the refrigerant transfer device of the use-side refrigerant cycle, sucks the liquid, and forcibly liquefies the separated gas into the liquid. Therefore, since the liquid is always sucked into the refrigerant transfer device, it is possible to prevent an accident such as the occurrence of burning due to poor lubrication caused by the suction of the gas by the rotary sliding portion that uses the liquid refrigerant as the lubricating oil. Further, since such a cooler is constituted by a heat source side refrigerant cycle, a separate cooling device is not required, and the structure can be simplified.

[Brief description of the drawings]

FIG. 1 is a refrigerant cycle diagram of an air conditioner in one embodiment of the present invention, FIG. 2 is a Mollier diagram showing an embodiment of the present invention, FIG. 3 is a refrigerant cycle diagram of a conventional air conditioner, FIG.
The figure is a Mollier diagram of a conventional example. 3 ... heat source side heat exchanger, 8 ... first auxiliary heat exchanger, 9 ...
... second auxiliary heat exchanger, 11 ... refrigerant transport device, 12 ... use side heat exchanger, 13 ... use side four-way valve, 14 ... gas-liquid separator,
14a ... inlet, 14b ... liquid outlet, 15 ... cooler, X ... heat source side refrigerant cycle.

Claims (1)

(57) [Claims] A compressor, a heat source side four-way valve, a heat source side heat exchanger,
A heat-source-side refrigerant cycle in which a decompression device and a first auxiliary heat exchanger are connected in a ring shape; a second auxiliary heat exchanger and a use-side heat exchanger which are formed integrally with the first auxiliary heat exchanger and exchange heat. And a refrigerant transport device in an annular connection, wherein an inlet, a liquid outlet, and a gas-liquid separator are provided on the suction side of the refrigerant transport device, and a cooler that promotes liquefaction of gas in the gas-liquid separator. And a cooling / heating device in which the cooler is connected to the heat source side refrigerant cycle.