JPH0430395Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a scroll compressor used in a refrigeration/air conditioning system, and is intended to improve oil supply to a swing bearing.

[Conventional technology]

FIG. 2 shows a hermetic scroll compressor for refrigeration and air conditioning, which is an example of a conventional scroll fluid machine.
Fig. 2 is a vertical cross-sectional view of a scroll compressor, in which a compression element section is arranged in the upper part of the main body, and an electric motor is arranged in the lower part. It consists of an anti-rotation member 3 etc. that prohibits rotation. In addition to these, there is a shaft 5 that connects the electric motor 4 and the compression element section, a frame 6 that locks the fixed scroll 1 and the electric motor 4, an upper bearing 71 and a lower bearing 72 that support the shaft 5, and a shaft that rotates the orbiting scroll 2. A supporting orbiting bearing 73, a thrust bearing 74 supporting the orbiting scroll 2 in the axial direction, and the like are housed in the housing 8. Lubricating oil 81 is sealed in the lower part of the housing 8 .

The fixed scroll 1 consists of an end plate 11 and a spiral 12 integrally formed with the end plate 11, and the end plate 11 is provided with a discharge port 13, a discharge valve 17, and a discharge cavity 14 on the opposite side of the spiral 12.

The orbiting scroll 2 consists of an end plate 21 and a spiral 22 integrally formed with the end plate 21, and furthermore, a boss 23 for driving the orbiting scroll 2 is provided on the opposite side of the spiral 22 of the end plate 21. An orbiting bearing 73 that connects the shaft 5 and the orbiting scroll 2 is disposed on the boss 23. Note that 84 is a balance weight attached to the shaft.

Next, the flow of refrigerant gas in the above scroll compressor will be explained. The low-temperature, low-pressure refrigerant gas returned to the compressor from the refrigeration/air conditioning unit (not shown) is introduced into the space inside the housing 8 through the suction pipe 82, cools the electric motor 4, and cools the electric motor 4, causing the entire outer periphery of the frame 6 to cool. The air is introduced into a suction chamber 16 provided outside of the fixed scroll 1 through a suction passage 15 provided in the fixed scroll 1 . electric motor 4
The orbiting scroll 2, driven by
The closed space 24 formed by 22 gradually decreases in size and reaches the center of the scroll. During this time, as the space volume decreases, the pressure and temperature of the refrigerant gas increases, and it is discharged from the discharge port 13 of the fixed scroll 1 to the discharge cavity 14 via the discharge valve 17, causing high temperature and high pressure inside the discharge cavity 14. The refrigerant gas is sent out to the outside of the compressor via the discharge pipe 83.

On the other hand, lubricating oil 8 stored at the bottom of the housing 8
1 is a centrifugal pump 51 provided on the shaft 5
A part of the oil is supplied to the lower bearing 72 through the oil supply hole 52 provided eccentrically from the center of the shaft, and is further supplied to the swing bearing 73, thrust bearing 74, rotation prevention member 3, etc. through the eccentric pin 53 of the shaft 5. The lubricating oil reaches the frame chamber 61 of the frame 6, lubricates the upper bearing 71, and is discharged from the oil drain hole 62 to the lower part of the housing 8.

[Problem that the invention attempts to solve]

Scroll compressors as described above have the following problems: Part or most of the refrigerant gas returned to the compressor from the refrigeration/air conditioning unit (not shown) is returned to the compressor as liquid refrigerant. In such a case, a large amount of liquid refrigerant will flow into the housing 8 from the suction pipe 82, and as a result, a large amount of liquid refrigerant will dissolve into the lubricating oil 81.

In such a case, the lubricating oil 81 in which a large amount of liquid refrigerant has been dissolved by the centrifugal pump 51 is pumped into the shaft 5.
However, the liquid refrigerant in the lubricating oil evaporates due to the heat generated by the electric motor 4 while going up the oil supply hole 52 and is sent to the swing bearing 73 via the eccentric pin 53. The amount of lubricating oil may be extremely reduced due to the gasification of the liquid refrigerant, resulting in poor lubrication of the swing bearing 73 and the like.

Further, the gasified refrigerant may cause so-called vapor leakage, and the lubricating oil may not flow to the swing bearing 73 or the like, and the swing bearing 73 or the like may seize.

[Means for solving problems]

An oil supply hole that penetrates the shaft and supplies lubricating oil at the bottom of the housing to the upper bearing part is provided eccentrically with respect to the axial center of the shaft, and a horizontally extending oil supply hole that opens into the oil supply hole at a position below the upper end of the shaft is provided. A gas vent hole is provided in a diametrical direction including the axial center of the shaft, and gas generated in the oil supply hole is discharged into the housing through the gas vent hole.

[Effect]

The refrigerant gas evaporated in the oil supply hole of the shaft by the gas vent hole is sent out to the outside of the oil supply hole, so lubricating oil remains in the oil supply hole and the lubricant is stably supplied to the swing bearing etc. via the eccentric pin part. It will be supplied to

〔Example〕

A specific example is shown in FIG. Components that are the same as those described in the prior art are given the same reference numerals and detailed explanations will be omitted. Similar to the conventional shaft 100, the shaft 100 has an eccentricity r, a centrifugal pump 51 is configured at the lower part of the shaft, and an oil supply hole 52 is provided in the shaft 100 at the position of the eccentricity r, which is connected to the eccentric pin 5.
Penetrate within 3.

A gas vent hole 101 having one end on the outer surface of the shaft is provided in an upper position of the bearing 72 on the side opposite to the oil supply hole with respect to the center of the shaft axis and in communication with the oil supply hole 52 in a direction substantially perpendicular to the oil supply hole. This gas vent hole 101
In order to vent the gas that has escaped into the housing 8a, a ring-shaped groove 105 is provided in the frame 6 at the position of the gas vent hole 101, and a gas discharge hole 106 is provided that communicates the groove 105 with the housing 8a.

Note that the ring-shaped groove 105 is not necessary if the frame 6 has a structure in which there is a sufficient clearance at the upper position of the bearing 72.

With the above configuration, lubricating oil in which a large amount of liquid refrigerant is dissolved is sent into the oil supply hole 52 by the centrifugal pump 51, and even if the liquid refrigerant is gasified by the heat generated by the electric motor, the gas vent hole 101 and gas vent groove 105, inside the housing 8 through the communication hole 106
is discharged to. Here, due to the centrifugal force, the lubricating oil in the oil supply hole 52 is not discharged from the gas vent hole 101, and the lubricant oil rises inside the oil supply hole 52.

Therefore, lubricating oil is stably supplied to the swing bearing 73 and other members, and the swing bearing 73 is stably supplied with lubricating oil.
Trouble caused by burn-in of the third grade will be resolved.

[Effect of idea]

When the liquid refrigerant in the lubricating oil evaporates due to the heat of the electric motor, the generated gas passes through the gas vent hole and is discharged into the housing.

In particular, by providing the gas vent hole in the shaft on the opposite side of the oil supply hole with respect to the center of the shaft axis, the distance between the end of the gas vent hole on the shaft surface and the center of the shaft is maximized, and the centrifugal force to remove gas is maximized. Therefore, the above effect appears most significantly.

Therefore, lubricating oil is smoothly supplied to the bearings, etc., and troubles such as seizure do not occur.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of essential parts of an embodiment of the scroll compressor of the present invention, and FIG. 2 is a general vertical cross-sectional view of a conventional scroll compressor. 6... Frame, 8a... Housing, 51...
... Centrifugal pump, 52 ... Oil supply hole, 100 ... Shaft, 101 ... Gas vent hole, 106 ... Gas discharge hole.

Claims (1)

[Scope of utility model registration request] In a scroll compressor in which a scroll compression element and an electric motor are supported within a housing via a support frame, and the scroll compression element and the electric motor are connected via a vertically rotating shaft, the bottom of the housing extends through the shaft. An oil supply hole for supplying lubricating oil to the upper bearing part is provided eccentrically with respect to the axial center of the shaft, and a horizontal gas vent hole that opens into the oil supply hole at a position below the upper end of the shaft is provided in the shaft. A scroll compressor characterized in that a gas exhaust hole is provided in a diametrical direction including the axial center and is provided in a position corresponding to the gas vent hole of the support frame and communicates with the gas vent hole.