JPH0341680B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a small rotary compressor used in a refrigerator-freezer or the like, and particularly relates to a technique for preventing a rise in the temperature of lubricating oil in the compressor.

Conventional configurations and their problems In conventional rotary compressors, the pressure inside the compressor shell is high, and the discharge gas is discharged into the shell, so the lubricating oil is lost due to the high-temperature, high-pressure gas and heat generated by the motor. There was a problem that deterioration was accelerated by exposure to high temperatures. For this reason, for example,
22035, one end of which is connected to an oil tank and the other end of a bypass path led out of the shell is connected to a communication hole to produce an ejector effect, and the lubricating oil is once led out of the shell to cool it. However, this technique has the drawback that the gas flow due to the ejector effect fluctuates due to changes in outside air temperature, causing a change in the amount of oil circulating through the bypass passage, making it impossible to maintain a sufficient amount of oil circulation required for oil cooling. Furthermore, when lubricating oil is once drawn out of the shell using a small rotary compressor such as that used in a household refrigerator, an oil choke phenomenon occurs due to the small output of the compressor, making it impossible to achieve a smooth cooling effect.

Purpose of the Invention Therefore, the present invention improves the unstable oil cooling method that is subject to fluctuations using ejectors, that is, the method of circulating the lubricating oil itself, and uses a refrigerant to cool down the temperature rise of the lubricating oil during compressor operation. The objective is to provide effective cooling in small capacity compressors and to provide a stable cooling effect continuously regardless of whether the compressor is running or stopping, thereby preventing lubrication failure due to an increase in lubricating oil temperature. .

Structure of the Invention In order to achieve this object, an electric element, a compression element, and a pump for supplying internal lubricating oil to the compression element are arranged in a high-pressure sealed shell, and a thermosiphon tube curved in a U-shape is arranged. The thermosiphon fin has an open end for sucking gas in the shell from inside the shell, a middle part extending outside the shell for cooling the gas, and a middle part for cooling the gas. It has an open end in the pump provided for dripping into the pump.

Description of an Embodiment In FIG. 1, 1 is the main body of a rotary compressor, and inside a high-pressure hermetic shell 1' there is a motor 2 as an electric element, a shaft 3 as a compression element, a piston 4, and bearings 5a, 5b. etc. are arranged.

6 is a suction pipe communicating with the compression element, and 7 is a discharge pipe communicating with the high pressure sealed shell 1'. Further, a discharge passage 8 for discharging the refrigerant compressed by the piston 4 is formed in the bearing 5b of the compression element, and this discharge passage 8 communicates with a discharge chamber 10 partitioned by a cover 9. is configured to discharge high-temperature, high-pressure refrigerant into the shell 1' from a discharge port 11 formed in the cover 9. Further, an oil supply pump 12 is installed at the tip of the cover 9, and one end of the oil supply pump 12 is immersed in the lubricating oil 13 inside the shell 1', and one end of the oil supply pump 12 is disposed inside the oil supply pipe 12a. is composed of a helical coil 12b connected to the end of the shaft 3 for rotational movement, and supplies lubricating oil 13 to the compression element.

On the other hand, 14 is a thermosiphon tube,
One opening end 14a is connected to the discharge port 11 within the shell 1'.
The other open end 14b is opened in communication with a part of the oil supply pipe 12a of the oil supply pump 12. Also, the middle part 14c of both opening ends 14a, 14b
is curved in a U-shape and extends outside the shell 1'. A fin 1 as an eliminator is provided on one opening end 14a side of the thermosiphon tube 14, that is, a portion facing the discharge port 11.
5 is installed and the middle part 14 extends outside the shell 1'.
A heat exchange fin 16 as a radiator is installed at each of the holes c.

Therefore, in the above configuration, gas sucked in through the suction pipe 6 by the rotational movement of the motor 2 is compressed by the piston 4, becomes high temperature and high pressure, is discharged into the shell 1', and is discharged from the discharge pipe 7. On the other hand, lubricating oil 13 is circulated to the compression element by an oil supply pump 12. That is, the lubricating oil 13 is circulated by the rotational movement of the helical coil 12b installed at the tip of the shaft 3.

Furthermore, since the inside of the shell 1' is filled with refrigerant gas and is at high temperature and pressure, the open end 1 of the thermosiphon tube 14 disposed in the oil supply pump 12
Introduce high-temperature, high-pressure gas inside shell 1' from 4a,
The liquid refrigerant, which is cooled and liquefied in the radiator 16 outside the shell and has increased in mass, flows down due to its own weight and flows down to the pump 12 as droplets, where it evaporates and vaporizes, directly affecting the lubricating oil 13 inside the pump 12. The oil droplets are separated by cooling and colliding the mixed droplets of refrigerant gas and lubricating oil discharged from the discharge port 11 with the fins 15 serving as eliminators. Since the gas temperature at the discharge port 11 is 20 to 30 degrees Celsius higher than the internal gas of the compressor, one side of the thermosiphon tube 14 is heated, and the thermosiphon action works extremely well, causing the inside of the fuel pump 12 to heat up. The cooling effect of the lubricating oil 13 is increased.

Effects of the Invention As is clear from the above explanation, the present invention cools the lubricating oil in the oil supply pump of a rotary compressor by means of a thermosiphon tube that uses high-temperature, high-pressure gas inside the compressor shell. Since it uses the physical phenomenon of refrigerant gas rather than the circulation of oil itself and does not use power, there is no energy loss, making it particularly effective for small compressors. Furthermore, by locating the open end of the thermosiphon tube in the shell near the discharge port, the siphon effect becomes large, and if an eliminator is configured at this open end, the presence of the tube will act as a lubricant/refrigerant separation effect. Can be used for both purposes.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a rotary compressor according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a main part of the compressor. 1'... High pressure sealed shell, 12... Pump (oil supply pump), 13... Lubricating oil, 14... Thermosiphon tube, 14a... One end (open end),
14b...Other end (open end), 14c...Middle part,
11...Discharge port, 5...Fin (eliminator).

Claims (1)

[Scope of Claims] 1. An electric element, a compression element, and a pump for supplying internal lubricating oil to the compression element are arranged in a high-pressure sealed shell, and a thermosiphon tube curved in a U-shape is provided, The siphon fin has an open end that sucks in the gas inside the shell from inside the shell, a middle part that extends outside the shell to cool the gas, and a part that drips the cooled gas in the middle part into the pump. What is claimed is: 1. A rotary compressor characterized by having an open end inside the pump provided for the purpose of the pump. 2. The rotary compressor according to claim 1, wherein the end portion of the thermosiphon tube that is opened into the shell is arranged opposite to the discharge port of the compression element. 3. The rotary type according to claim 1 or 2, wherein an eliminator is provided at an end of the thermosiphon tube to separate the discharged gas of the oil/refrigerant mixture discharged from the discharge port. compressor.