JPS6340277B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a compressor configured by combining a low pressure dome type compressor and a high pressure dome type compressor.

Conventionally, it has been known to combine two hermetic compressors and control the capacity by operating either or both of them. However, in this case, suction and discharge piping for both compressors are required separately, and
The drawback is that space is required for piping, making the entire device larger.

The present invention aims to eliminate the above-mentioned defects and provide a combination type compressor that is small and compact and whose capacity can be controlled. A part or all of a small-capacity high-pressure dome compressor is housed in the low-pressure casing of the high-pressure dome compressor, and a discharge pipe of the low-pressure dome compressor is connected to the high-pressure casing of the high-pressure dome compressor. The structure is characterized in that the suction pipe of the dome-shaped compressor is opened into the low pressure casing.

Hereinafter, a compressor according to an embodiment of the present invention will be described with reference to the accompanying drawings.

This compressor is constructed by housing a high-pressure dome-type compressor 2 together with a large-capacity reciprocating compressor main body 12 in a low-pressure casing 11 of a low-pressure dome-type compressor 1 .

That is, the low-pressure casing 11 is formed slightly larger, and the high-pressure casing 21 of the high-pressure dome compressor 2 is welded to the mounting hole 11b formed in the top surface 11a of the low-pressure casing 11 with the top surface 21a exposed. At the same time, the bottom surface 21b of the high pressure casing 21 is supported and fixed by a stay 3 fixed to the inner surface of the low pressure casing 11.

The high-pressure dome compressor 2 is constructed by disposing a small-capacity rotary compressor main body 22 within a high-pressure casing 21.

The reciprocating compressor main body 12 has a cylinder 1 driven by a reciprocating piston 14 driven by an electric motor 13.
is configured to perform a compression action within 5;
It is elastically supported by a spring 16 within a low pressure casing 11 which is in an atmosphere of suction gas.

On the other hand, the rotary compressor main body 22 is configured to perform compression within a cylinder 25 by a rotary piston 24 driven by an electric motor 23, and the high-pressure casing 21 is in a discharge gas atmosphere.
It is press-fitted inside.

The discharge pipe 18 of the reciprocating compressor main body 12 is connected to the upper part of the high pressure casing 21, while the suction pipe 26 of the rotary compressor main body 22 is connected to the low pressure casing 11.
It is opened inward.

Note that the suction pipe 17 of the low-pressure dome compressor 1 and the discharge pipe 27 of the high-pressure dome compressor 2 are each connected to external equipment (for example, an evaporator and a condenser).

In addition, the suction pipe 26 of the high pressure dome compressor 2 includes:
A capillary tube 4 for oil suction is connected from below, and the lower end opening 4a of the capillary tube 4 is slightly above the appropriate oil level l of the lubricating oil stored in the oil reservoir 19 at the inner bottom of the low pressure casing 11. I am faced with this.

Reference numeral 28 is an oil reservoir at the inner bottom of the high-pressure casing 21 .

Next, the operation of the illustrated compressor will be explained.

When operating two compressors 1 and 2 at the same time,
The suction gas is supplied through the suction pipe 17 and the low pressure casing 1.
1 into the cylinder 15 of the reciprocating compressor main body 12, while the suction pipe 17 and the low pressure casing 11
The air is then sucked into the cylinder 25 of the rotary compressor main body 22 through the suction pipe 26. Therefore, even if there is a large amount of unevaporated refrigerant in the suction gas refrigerant, the low pressure casing 11 acts as an accumulator for the high pressure dome compressor 2, and liquid back up can be prevented.

Further, the discharge gas of the reciprocating compressor main body 12 passes through the discharge pipe 18 and joins with the discharge gas of the rotary compressor main body 22 in the high-pressure casing 21, and then is led out from the discharge pipe 27. Therefore, the high-pressure casing 21 acts as a discharge muffler for the low-pressure dome compressor 1, and a separately installed discharge muffler is not required.

During operation under this system, the oil level in the oil reservoir 19 of the low pressure casing 11 becomes higher than the appropriate oil level l, and the lower end opening 4 of the capillary tube 4
Above a, the lubricating oil is returned to the high-pressure casing 21 together with the suction gas refrigerant via the capillary tube 4 by the ejector action in the suction pipe 26 . On the contrary, the oil sump part 2 of the high pressure casing 21
If too much lubricating oil accumulates in 8, the high pressure casing 21
As a result, the oil separation function inside the lubricant is significantly reduced, and as a result, the lubricating oil mixes with the discharge gas and flows out to the external equipment side, resulting in a large amount of oil being returned from the external equipment to the low-pressure casing 11, which is sucked in first. .

Next, when the high pressure dome type compressor 2 is stopped and only the low pressure dome type compressor 1 is operated, and conversely, when the low pressure dome type compressor 1 is stopped and the high pressure dome type compressor 2 is operated,
When only the high-pressure dome compressor 2 or the low-pressure dome compressor 1 is stopped, the process is exactly the same as when the two compressors are operated at the same time, and the lubricating oil between them is evenly distributed. This is also done in the same manner as when the two units are operated.

Therefore, by appropriately selecting the capacity ratio of the low-pressure dome compressor 1 and the high-pressure dome compressor 2 and operating both simultaneously or only one of them, capacity control operation that matches the load can be achieved. This makes it possible to apply this method to power-saving refrigeration systems.

In addition, in the illustrated embodiment, the low pressure casing 11
Although a part of the high-pressure dome compressor 2 is housed inside the casing 11 with a part exposed to the outside, it is possible to configure the high-pressure dome compressor 2 to be entirely housed inside the low-pressure casing 11. Of course.

Next, the effects of the compressor of the present invention will be listed below.

That is, according to the present invention, (1) a small-capacity high-pressure dome-shaped compressor 2 is placed in a low-pressure casing 11 of a large-capacity low-pressure dome-shaped compressor 1;
(2) The low-pressure dome type compressor The discharge pipe 18 of 1 is connected to the high pressure casing 21 of the high pressure dome type compressor 2.
(3) The suction pipe 26 of the high pressure dome compressor 2 is connected to the low pressure Since the opening was made inside the casing 11,
The low-pressure casing 11 functions as an accumulator for the high-pressure dome compressor 2, which has practical effects such as further downsizing and cost reduction of the compressor.

[Brief explanation of the drawing]

The drawing shows a longitudinal sectional view of a compressor according to an embodiment of the invention. DESCRIPTION OF SYMBOLS 1...Low pressure dome compressor, 2...High pressure dome compressor, 11...Low pressure casing, 18...Discharge pipe, 21...High pressure casing, 26...Suction pipe.

Claims (1)

[Claims] 1 Part or all of the small capacity high pressure dome compressor 2 is accommodated in the low pressure casing 11 of the large capacity low pressure dome compressor 1, and the discharge pipe 18 of the low pressure dome compressor 1 is connected to the high pressure A compressor characterized in that the suction pipe 26 of the high pressure dome type compressor 2 is opened into the low pressure casing 11 while being connected to the high pressure casing 21 of the dome type compressor 2.