JP2002243314A - Air conditioning apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioning apparatus capable of avoiding unevenness of a refrigerant caused by transient liquid back and also avoiding excessive capacity up of an accumulator. SOLUTION: An air conditioning apparatus is adapted such that a plurality of outdoor units are provided, which outdoor units are connected in parallel to an inter-unit piping composed of gas pipes and liquid pipes connected to indoor unit through branch gas pipes and branch liquid pipes. In the air conditioning apparatus, an assembly branch structure 50 is adopted at a branch section extending from the foregoing gas pipe 5 to the branch gas pipes 51A, 51B, 51C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner in which a plurality of outdoor units are connected in parallel to an interunit pipe extending from an indoor unit.

[0002]

2. Description of the Related Art Generally, there are provided a plurality of outdoor units having an outdoor heat exchanger, a compressor and an oil separator, and returning the oil separated by the oil separator to the compressor via an oil return pipe. There is known an air conditioner in which these outdoor units are connected in parallel to interunit piping extending from the indoor units. In this type, it is general that each outdoor unit is connected in parallel to a gas pipe and a liquid pipe constituting a pipe between the units via a branch gas pipe and a branch liquid pipe.

In the conventional configuration, as shown in FIG. 4, cheese 62A, 62B and elbow 6 are connected to gas pipe 61 in particular.
It is general that branch gas pipes 63A, 63B, 63C are connected using 2C, and an outdoor unit is connected thereto.

[0004]

However, according to the conventional structure, when the gas refrigerant flows through the gas pipe 61, the gas refrigerant does not have much straightness.
The gas refrigerant is almost evenly distributed to C. However, if a transient liquid back occurs and a liquid refrigerant flows through the gas pipe 61, the elbow 62 C
In addition, there is a problem that a large amount of refrigerant flows unevenly in the branch gas pipe 63C. In such a case, a large amount of liquid refrigerant flows into the outdoor unit connected thereto, so that it is necessary to take measures such as increasing the accumulator capacity of the outdoor unit.

Accordingly, an object of the present invention is to provide an air conditioner which solves the above-mentioned problems of the prior art, avoids bias of the refrigerant due to transient liquid back, and can also avoid excessive increase in the capacity of the accumulator. To provide.

[0006]

According to the first aspect of the present invention,
In an air conditioner comprising a plurality of outdoor units, the plurality of outdoor units are connected in parallel via a branch gas pipe and a branch liquid pipe to a unit pipe consisting of a gas pipe and a liquid pipe connected to the indoor unit, A branching structure is adopted at a branching portion from the gas pipe to the branch gas pipe.

According to a second aspect of the present invention, in the first aspect, a plurality of outdoor units are provided, and the plurality of outdoor units are connected to a unit-to-unit piping comprising a gas pipe and a liquid pipe connected to the indoor unit. In an air conditioner connected in parallel via a branch gas pipe and a branch liquid pipe, a collective branch structure is adopted at a branch part from the gas pipe to the branch gas pipe, and the collective branch structure blocks the end of the gas pipe. And a merging header section orthogonally displaced from the merging section, wherein the branch gas pipes are connected to the merging header section at equal intervals.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numerals 1A and 1B denote outdoor units. These outdoor units 1A and 1B are connected in parallel to an inter-unit pipe 9 composed of a gas pipe 5 and a liquid pipe 7 connected to the indoor units 3A to 3D.

The outdoor units 1A and 1B include compressors 11A and 11B driven by gas engines, oil separators 12A and 12B, four-way valves 13A and 13B, outdoor heat exchangers 14A and 14B, outdoor fans 17A and 17B, and expansion valves. 1
5A, 15B, and other accumulators 16A, 16B. In addition, indoor units 3A-3
D is the indoor heat exchangers 34A to 34D, the indoor fan 37A
To 37D and indoor electric expansion valves 39A to 39D.

During the heating operation, the four-way valves 13A and 13B are switched to a dotted line state. The refrigerant from the compressors 11A and 11B is supplied to the oil separator 1 as indicated by the dotted arrows.
After passing through 2A, 12B and four-way valves 13A, 13B, they enter the branch gas pipes 5A, 5B, join the gas pipes 5, and flow into the indoor units 3A to 3D.

Through the indoor heat exchangers 34A to 34D and the indoor electric expansion valves 38A to 38D, they merge into the liquid pipe 7, pass through the receiver tank 33, and enter the outdoor units 1A and 1B.
Outdoor heat exchangers 14A, 14B, four-way valves 13A, 13B,
Through the accumulators 16A and 16B, the compressors 11A,
It is returned to the suction pipe of 11B.

During the cooling operation, the four-way valves 13A and 13B are switched to the solid line state. The refrigerant from the compressors 11A and 11B is supplied to the oil separator 1 as indicated by solid arrows.
After passing through 2A, 12B and four-way valves 13A, 13B, they enter the outdoor heat exchangers 14A, 14B, and reach the liquid pipe 7 and the receiver tank 33 through expansion valves 15A, 15B.

From there, enter the indoor units 3A to 3D,
Indoor electric expansion valves 38A-38D, indoor heat exchanger 34A-
34D, the gas enters the gas pipe 5 and branches into the branch gas pipes 5A, 5B.
A, 13B, and are returned to the suction pipes of the compressors 11A, 11B via the accumulators 16A, 16B.

In this embodiment, the branch gas pipe 5 is connected to the gas pipe 5 constituting the inter-unit pipe 9 via the collective branch structure 50.
A and 5B are connected.

FIG. 2 shows the set branch structure 50. However, FIG. 1 shows an example using two branch gas pipes 5A and 5B, but FIG. 2 shows three branch gas pipes 51A, 51B and 51C for convenience of explanation, 51
A structure in which an outdoor unit is connected to each of A, 51B, and 51C will be described as an example. This is because a remarkable branching effect can be obtained when three or more branch gas pipes are provided. Here, the end of the gas pipe 5 is closed. The collective branch structure 50 includes a merging header portion 53 that is orthogonally displaced (preferably vertically upward) from the end closing portion 5C of the gas pipe 5 by a predetermined dimension D. On the other hand, branch gas pipes 51A, 51
B and 51C are mutually connected at equal intervals in the circumferential direction.

As shown in FIG. 3, the merging header section 53 is connected to the gas pipe 5 via an orthogonal pipe 53B.
The inside of the merge header section 53 has three chambers 54A to 54C (chamber 54).
A, 54B only) are divided into
The flow path cross-sectional areas of 4C are set equal to each other.

For example, during the heating operation, if a transient liquid back occurs in the refrigerant returning from the indoor unit to the outdoor unit, the liquid refrigerant flows into the gas pipe 5.

In the present embodiment, the liquid refrigerant having entered the gas pipe 5 has a straight running property and heads toward the end closing portion 5C, once hits the wall of the end closing portion 5C, and then reverses the traveling direction. The refrigerant is returned to the inflow side. During this time, the liquid refrigerant is rectified. After that, the gas flows into the orthogonal pipe 53B of the collective branch structure 50, enters the merge header 53, passes through the chambers 54A to 54C having substantially the same cross-sectional area of the flow path, and passes through the branch gas pipes 51A, 51B, 5C.
It branches into 1C and flows into each outdoor unit.

In the present embodiment, a collective branching structure 50 mounted orthogonally to the gas pipe 5 is employed. Return to the inflow side, during which the liquid refrigerant is rectified,
Since the passages 54A to 54C formed in the joining header portion 53 and having the same flow passage cross-sectional area are joined, the branching effect can be improved. Therefore, the disadvantage that a large amount of liquid refrigerant is returned to any one of the outdoor units is eliminated, so that an excessive increase in the capacity of the accumulator can be avoided.

Although the present invention has been described based on one embodiment, it is clear that the present invention is not limited to this.

[0022]

According to the present invention, it is possible to prevent the refrigerant from being biased due to the transient liquid back, and to prevent the capacity of the accumulator from being excessively increased.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram showing an embodiment of an air conditioner according to the present invention.

FIG. 2 is a perspective view illustrating a collective branch structure according to an embodiment of the present invention.

FIG. 3 is a sectional view thereof.

FIG. 4 is a diagram showing a conventional set branch structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1A, 1B Outdoor unit 3A-3D Indoor unit 5 Gas pipe 5C Terminal blockage part 7 Liquid pipe 9 Unit piping 50 Collective branch structure 51A, 51B, 51C Branch gas pipe 53 Merging header part

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshito Tajima 1 Otsukicho, Ashikaga, Tochigi Sanyo Electric Air Conditioning Co., Ltd. (72) Inventor Yoshiro Goto 1 Otsukicho, Ashikaga, Tochigi Sanyo Electric Air Conditioning Co., Ltd. In-house (72) Ryota Hirata, 1 Otsukicho, Ashikaga, Tochigi Prefecture Sanyo Electric Air Conditioning Co., Ltd. (72) Inventor Junji Matsue, 1 Otsukicho, Ashikaga, Tochigi Prefecture, Sanyo Electric Air Conditioning Co., Ltd.

Claims (2)

[Claims] 1. A plurality of outdoor units are provided, and the plurality of outdoor units are connected in parallel to a unit pipe consisting of a gas pipe and a liquid pipe connected to the indoor unit via a branch gas pipe and a branch liquid pipe. The air conditioner according to claim 1, wherein a branching structure is adopted at a branch portion from the gas pipe to the branch gas pipe. 2. A plurality of outdoor units are provided, and the plurality of outdoor units are connected in parallel to a unit pipe consisting of a gas pipe and a liquid pipe connected to the indoor unit via a branch gas pipe and a branch liquid pipe. In the air-conditioning apparatus, a collective branch structure is adopted in a branch portion from the gas pipe to the branch gas pipe, and the collective branch structure includes a merging header section orthogonally displaced from an end closing part of the gas pipe, The air conditioner, wherein the branch gas pipes are connected to the merging header section at equal intervals.