JPH0441988A - Rotary compressor - Google Patents

Abstract

PURPOSE:To prevent a cover packing from being reduced in its sealing performance and from being lack of lubricating oil even after such impact due to dropping as causing a rotational shaft to be moved downwardly by restricting the downward movement into a very small amount within an elastic deformation of cover packing by means of a projecting portion as a stopper. CONSTITUTION:In ordinary operation of a rotary compressor 11, the thrust force of a rotational shaft 17 is supported by a thrust plate 27, and a projecting portion 30 as a stopper is rotated in non-contact with the thrust receiving surface 20c of a sub-bearing 20. Consequently, the sub-bearing 20 is small in its sliding resistance and wear. When the rotary compressor 11 is dropped during its transfer, the rotational shaft 17 is moved downwardly by the impact due to dropping. In this case, the projecting portion 30 as a stopper is touched onto the thrust receiving surface 20c, so that the downward movement is restricted into a micro-gap DELTAg. The cover packing 28 is only elestically deformed thereby preventing the plastic deformation. As a result, it is possible to prevent the cover packing 28 from being lack of lubricating oil due to the plastic deformation thereof.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a rotary compressor suitable as a compressor incorporated in a refrigeration cycle of an air conditioner, etc.
In particular, the present invention relates to a rotary compressor with an improved structure that receives thrust from a rotating shaft of a motor section.

(Prior Art) Conventionally, this type of rotary compressor has a motor section and a rotary compression mechanism driven by the motor section arranged above and below inside a sealed case.

The rotating shaft of the motor section is rotatably supported by a main bearing, a sub-bearing, etc., and the cylinder of the compression mechanism is held between the upper and lower sides by these bearings.

A roller is housed in this cylinder so that it can freely rotate eccentrically.
This roller is fitted onto the eccentric portion of the rotating shaft so as to be eccentrically rotatable, and as the rotating shaft rotates, the mouth roller rotates eccentrically within the cylinder to compress the refrigerant and the like.

FIG. 4 shows a structure that receives the thrust of the rotating shaft, in which the lower end of the rotating shaft 1 is connected to the bearing hole 2a of the sub-bearing 2.
It is inserted inside and supported rotatably.

The sub-bearing 2 is attached to the lower end of the opening of the bearing hole 2a by a valve cover 6 via a cover gasket 4 that elastically presses the thrust plate 3 from its lower surface.

Therefore, the thrust of the rotating shaft 1 is the thrust of the thrust plate 3.
and elastically supported by the cover packing 4. Further, as the rotary shaft 1 rotates, the lubricating oil stored around the valve cover 6 can be supplied upward through an oil supply groove (not shown) formed on the inner circumferential surface of the lower end thereof.

(Problems to be Solved by the Invention) However, in such a conventional rotary compressor, as shown in FIG. Since there is a relatively large gap g between them, when the rotating shaft 1 moves downward as shown by the arrow in FIG. 4 downward and attach this thrust plate 3 and cover gasket 4 to the sub bearing 2.
In some cases, the cover gasket 4 may fall off or the cover gasket 4 may be plastically deformed.

In this case, the seal with the valve cover 6 becomes defective, so high-pressure gas such as refrigerant discharged from the compression mechanism into the valve cover 6 enters the bearing hole 2a of the sub-bearing 2 through the defective seal and supplies lubrication. interfere with This may lead to poor lubricating oil supply, resulting in a problem of reduced reliability.

The present invention has been made in consideration of the above circumstances, and its object is to provide a highly reliable rotary compressor that can prevent a large downward movement of the rotating shaft.

[Structure of the invention]

(Means for Solving the Problem) The present invention has been made in view of the fact that the problem with the conventional example is that the thrust of the rotating shaft is supported by a thrust plate, cover packing, etc. A stopper is provided on the eccentric portion of the rotating shaft to restrict the downward movement of the rotary shaft, and is constructed as follows.

In other words, in the present invention, a motor section and a compression mechanism are disposed one above the other, a roller of the compression mechanism is externally fitted onto an eccentric part of a rotating shaft of the motor section so as to be eccentrically rotatable, and a part of the rotating shaft is inserted into a bearing hole. In a rotary compressor, a thrust plate that receives the thrust of the rotating shaft is attached to a sub-bearing that is rotatably inserted into and supported by a support member via an elastic member. A convex portion having a diameter larger than the diameter of the bearing hole of the sub-bearing is formed, and the thrust plate and the supporting member The present invention is characterized in that a gap is provided that is smaller than the interval obtained by subtracting the plate thickness of the elastic member from the interval.

(Function) When the rotary compressor falls, for example, during transportation, the rotating shaft of the motor section tries to move downward due to the impact of the fall, but the downward movement is equivalent to the gap between the convex part of the stopper and the sub-bearing. Although it moves slightly,
Further downward movement is restricted by the convex portion of the stopper.

Since this gap is set to be smaller than the gap between the thrust plate and the support member minus the plate thickness of the elastic member, the thrust plate and the support member are moved downward by the minute movement of the rotating shaft. Even if I push it,
The elastic member is only elastically deformed, and the elastic member is plastically deformed, thereby preventing sealing failure of the support member and lubricating oil supply failure, thereby increasing reliability.

(Example) An example of the present invention will be described below based on FIGS. 1 to 3.

FIG. 3 is a vertical sectional view of the overall configuration of an embodiment of the present invention. In the figure, a rotary compressor 11 has a rotary compression mechanism 13 and a motor section 14 for driving it built in a sealed case 12. ing.

In the motor section 14, a rotating shaft 17 extending vertically in the figure is fixed coaxially to the axial center of a rotor 16 rotating within a stator 15, and the tip of this rotating shaft 17 (lower end in the figure) It is rotatably supported by a bearing 18 and a sub-bearing 20.

The main bearing 18 and the sub-bearing 20 are connected to the first and second cylinders 21 of the compression mechanism 13 arranged in two stages, upper and lower.
．． 22 is held between the top and bottom, and both cylinders 21.
An intermediate partition plate 19 is interposed between 22.

First and second eccentric parts 23, 24 are integrally connected to each penetrating part of the rotating shaft 17, which passes through the cylinders 21, 22, respectively, with the phases shifted from each other.

The first and second rollers 25 and 26 of the compression mechanism 13 are fitted around the outer periphery of each eccentric portion 23 and 24, respectively, and the rotation shaft 17
Due to the rotation of each eccentric part 23, 24 and rollers 25, 2
6 rotate eccentrically, each cylinder 21.
The refrigerant etc. inside 22 are compressed.

As shown in FIG. 1, the sub-bearing 26 has a thrust plate 27 made of an elastic member at the lower end of the opening in the figure of the boss portion 20b of the bearing hole 20a into which the lower end portion 17a of the rotary shaft 17 is rotatably inserted. It is attached by a valve cover 29 which is a supporting member through a certain cover gasket 28, and the thrust of the rotating shaft 17 is connected to the thrust plate 27.
The cover gasket 28 seals high pressure gas such as refrigerant discharged into the valve cover 29.

Further, the rotating shaft 17 has an oil supply groove (not shown) formed on the inner circumferential surface of its lower end 17a, etc., and the rotation of the rotating shaft 17 causes the valve cover 29, which is immersed in a not-shown lubricating oil reservoir, to Lubricating oil is supplied to the upper part of the rotating shaft 17.

Furthermore, the rotating shaft 17 is integrally connected to the lower end of the second eccentric part 24 by eccentrically attaching a stopper convex part 30 having a slightly smaller diameter than this eccentric part 24 and a larger diameter than the bearing hole 20a of the sub-bearing 20. When the rotary shaft 17 moves downward in the figure, the lower surface of this stopper projection 30 is brought into contact with the thrust receiving surface 20c of the sub-bearing 20 on the upper surface in the figure, thereby restricting the downward movement. It is supposed to be done.

A minute gap Δg is set between the lower surface of the stopper convex portion 30 in the drawing and the thrust receiving surface 20c of the sub-bearing 20.

The minute gap Δg is between the thrust plate 27 and the valve cover 2.
The gap is set to be smaller than the distance from the cover gasket 9 minus the plate thickness of the cover gasket 28, and is set within the elastic deformation of the cover gasket 28.

Next, the operation of this embodiment will be explained.

During normal operation of the rotary compressor 11, the rotating shaft 17
The thrust is supported by the thrust plate 27, and the stopper convex portion 30 rotates without contacting the thrust receiving surface 20c of the sub-bearing 20, so the sliding resistance and wear of the sub-bearing 20 are small.

If, for example, the rotary compressor 11 falls during transportation, the rotating shaft 17 will move downward due to the impact, but at that time, the stopper convex portion 30 will hit the thrust receiving surface 20C of the sub-bearing 20. Its downward movement stops at the minute gap Δg, and further downward movement is restricted.

Then, when the rotating shaft 17 moves downward by the minute gap Δg, the cover gasket 28 only undergoes elastic deformation, and its plastic deformation is prevented.

Therefore, a shortage of lubricating oil due to plastic deformation of the cover gasket 28 can be prevented, and reliability can be improved.

Note that the stopper convex portion 30 may be formed by increasing the thickness of the second eccentric portion 24 of the rotating shaft 17.

〔Effect of the invention〕

As explained above, in the present invention, the downward movement of the rotating shaft can be restricted to a minute amount within the elastic deformation of the cover gasket, etc. by the convex portion for the stopper, so that the downward movement of the rotating shaft can be restricted to a minute amount within the elastic deformation of the cover gasket. Even after an impact, it is possible to prevent the sealing function of the cover gasket from deteriorating, prevent a lack of lubricating oil, and improve reliability.

Roller, 27...Thrust plate, 28...Cover gasket, 29...Valve cover, 30...Step for stopper, 6g...Minute gap.

Claims (1)

[Claims] A motor section and a compression mechanism are arranged one above the other, a roller of the compression mechanism is fitted onto an eccentric portion of a rotating shaft of the motor section so as to be eccentrically rotatable, and a part of the rotating shaft is rotatably inserted into a bearing hole. In a rotary compressor in which a thrust plate that receives the thrust of the rotating shaft is attached to a supporting sub-bearing via an elastic member by a supporting member, a bearing hole of the sub-bearing is provided at the lower end of the eccentric part of the rotating shaft. A convex portion having a diameter larger than the hole diameter is formed between the convex portion and the thrust receiving surface of the sub-bearing that receives the thrust of the convex portion. A rotary compressor characterized in that a gap is provided that is smaller than the gap obtained by subtracting the plate thickness of the members.