JPS5823539B2 - Refrigeration equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a refrigeration system suitable for a heat pump air-conditioning system.

In general, for example, in a heat pump air-conditioning system, it is necessary to provide a difference in capacity between heating operation and cooling operation, and the capacity of the compressor is controlled.

- The present invention aims to provide a refrigeration system that can perform such capacity control simply and in multiple stages using a rotary set of multiple cylinder compressors.

An embodiment of the present invention will be described based on the drawings.

In Figs. 1 to 3, reference numeral 1 denotes a multi-cylinder compressor having a plurality of mutually independent sets of rotary complete compression elements 2, 3, and each compression element 2, 3 has a single rotary compressor driven by an electric element 4. It has a rotor 6.7 vertically connected to the shaft 5, a cylinder 12.13 housing the rotor 6.7 and having suction ports 8, 9 and a discharge port 10.11, fixed blades 14.15, and the like.

The discharge ports 10 and 11 communicate with the inside of the compressor 1 through pipes 16 and 17 to form a refrigerant passage for cooling the electric element 4.

The first cylinder 12 and the second cylinder 13 are separated by a partition wall 18, and by setting the outer diameter of the first rotor 6 smaller than that of the second rotor 7, the first compression element 2 The displacement volume of the second compression volume 3 is made larger than that of the second compression volume 3, and the suction and discharge capacities are set to be large.

19 is a four-way switching valve; 20 is an indoor air-to-refrigerant heat exchange type user-side heat exchanger equipped with a blower 21; 22 and 23 are a cooling pressure reducing device and a heating pressure reducing device each consisting of a capillary tube;
425 is a check valve connected in parallel with each pressure reducing device 22, 23, 26 is an outdoor air to refrigerant heat exchange type heat source side heat exchanger 39 equipped with a blower 27 is a gas-liquid separator, and these elements are connected in a ring as shown in the figure to form a refrigerant circuit.

Suction pipes 30, 31 each having a solenoid valve 2,8,29 are connected to each cylinder 12, 13 of the compression elements 2, 3, and the suction pipe 30, 31 is connected to a high-pressure liquid pipe section 32 of the refrigerant circuit. An injection tube 37.38 with a capillary tube 33.34 and a capillary tube 35.36 is also connected.

The above-mentioned solenoid valves 28, 29, 33, and 34 are controlled using a microcomputer, etc., as an example. During cooling, the solenoid valves 28, 33 open and solenoid valves 29 and 34 close, and during heating, each solenoid valve is controlled by the indoor load. Accordingly, it is automatically controlled as described below.

The embodiment is configured as described above, and the solenoid valve 2 is closed during cooling.
8.33 opens and solenoid valve 29.34 closes, so the refrigerant discharged from the compressor 1 moves from 9 to 2 as shown by the broken line arrow in FIG.
The liquid flows in the order of 6→25→22→20→9→39→30→1, and liquid injection into the cylinder 12 is performed through the injection pipe 37.

The room is cooled by evaporation in the user-side heat exchanger 20.

Further, during heating, each electromagnetic valve is controlled to open and close as shown in FIG. 4, and heating capacity is controlled in eight stages.

First, in the first stage, the strongest state, all solenoid valves are 28°29.
33 and 34 are opened, and the refrigerant discharged from the compressor 1 is 9
→20→24→23→26→9→.

39 and flow suction pipes 30, 31 into each black line element 2, 3 of the compressor 1, and the utilization side heat exchanger 20 acts as a condenser, thereby heating the room.

At this time, refrigerant is sucked into each compression element 2, 3 through the injection pipes 37, 38.

Therefore, the amount of refrigerant circulating through the user-side heat exchanger 20 is the sum of the amounts of refrigerant flowing through the suction pipes 30.31 and injection pipes 37.38, and since the amount of refrigerant circulated is the maximum, the heating capacity is also maximized.

And in the second stage control, the injection pipe 33.3
As the stage increases, the amount of refrigerant sucked into the compressor 1 gradually decreases. .

As a result, the amount of refrigerant circulated in the user-side heat exchanger 20 decreases, and the heating capacity decreases in stages.

Although the above embodiment does not control the capacity of the compressor during cooling, it is possible to control the capacity as required, such as when the cooling load is large.

Further, the number of compression elements 2.3 can be increased to 3 or more, and the capacities of compression elements 2 and 3 may be equal.

The present invention is constructed as described above, and each suction pipe 30.3
By controlling the opening and closing of the solenoid valves of 1 and each injection pipe 37, 38, the capacity can be easily controlled in multiple stages, and other great effects are achieved.

[Brief explanation of the drawing]

Fig. 1 is a refrigerant circuit diagram of an embodiment of the present invention, Fig. 2 is a schematic cross-sectional view of main parts of the same embodiment, Fig. 3 A 2 is an enlarged detailed cross-sectional view of different parts of Fig. 2, Fig. 4 The figure is an explanatory diagram showing the control mode and capacity stages of the electromagnetic valve of the same embodiment. 1... Compressor, 2, 3... Compression element, 6, 7...
Rotor, 12.13...Cylinder, 20...Using side heat exchanger, 26...Heat source side heat exchanger, 28.29,3
3゜34... Solenoid valve, 30, 31... Suction pipe, 37
, 38...injection tube.

Claims (1)

[Scope of Claims] 1. A refrigerant circuit is constructed by connecting a plurality of cylinder compressor JU side heat exchangers, pressure reducing devices, and heat source side heat exchangers in a ring shape, in which a plurality of compression elements each having a rotor and a cylinder are assembled. , respectively for each cylinder. A refrigeration system characterized in that a suction pipe having a solenoid valve is connected thereto, and an injection pipe communicating with a high pressure liquid pipe portion of the refrigerant circuit and having a solenoid valve and a capillary tube, respectively, is connected thereto.