JP2000002250A - Shell type needlelike roller bearing for scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve lubrication performance in bearings and durability thereof. SOLUTION: Flanges 11a provided at both axial ends of an outer race 11 are bent to an inner diameter side. A radial size T between an outer diameter of the axial opposed ends of the outer race 11 and an inner diameter of the flange 11a is set 2.3 times a wall thickness (t) in an axial center including a track surface of the outer race 11. A radial size (t') between an inner diameter of axial center of the outer race 11 and an inner diameter of the flange 11a is set 1/2 times a diameter dw of a needle-like roller 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved shell-type needle roller bearing for a scroll compressor, which is used to rotatably support an orbiting scroll member with respect to an eccentric shaft of the scroll compressor.

[0002]

2. Description of the Related Art As shown in FIG. 4, a scroll compressor is composed of a spiral scroll member 3 eccentrically rotated by an eccentric shaft 2 rotationally driven by a drive motor 1 and a stationary scroll member 4 opposed thereto. 3a, 4a are provided, respectively, and the volume of the compression chamber 5 formed between the two spiral partition walls 3a, 4a is changed according to the eccentric rotation (scroll rotation) of the orbiting scroll member 3 with respect to the stationary scroll member 4, thereby compressing. Working medium (refrigerant) in chamber 5
Is performed.

In order to rotatably support the orbiting scroll member 3 with respect to the eccentric shaft 2 of the scroll compressor, a shell-shaped needle roller bearing A as shown in FIG. 5 is generally used. This shell-shaped needle roller bearing A is
An outer ring 6 made of a thin steel plate fixed to the orbiting scroll member 3 and having flanges 6 a at both ends in the axial direction, and a plurality of needles interposed between a raceway surface of the outer ring 6 and an outer peripheral surface of the eccentric shaft 2. The roller includes a roller 7 and a retainer 8 for holding the needle roller 7 at a predetermined circumferential interval.

[0004]

The above-described needle roller bearing A is operated at a high speed and lubricated by a small amount of lubricant contained in the refrigerant. Strictly, how much lubricating oil flows into the bearing is the key to achieving a longer life.

However, in the above-described conventional needle needle roller bearing A, flanges 6a provided at both axial ends of the outer ring 6 are
Since the structure is bent at a right angle toward the inner diameter side, a large lubricating oil inflow area cannot be obtained at the flange 6 a of the outer ring 6.
This makes it difficult for the lubricating oil to flow into the bearing, so there is concern about the lubrication performance in the bearing, which may lead to a decrease in the durability of the bearing.

Accordingly, an object of the present invention is to provide a shell-type needle roller bearing for a scroll compressor capable of improving the lubrication performance in the bearing and the durability of the bearing.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an eccentric rotary movement of an eccentric shaft for eccentrically orbiting a orbiting scroll member with respect to a stationary scroll member to compress the working medium in a compression chamber. A shell-type needle roller bearing used in a scroll compressor that performs the following, and is fixed to the orbiting scroll member, and has an outer ring made of a thin-walled steel plate having a flange portion formed by folding inwardly at both ends in the axial direction. A plurality of needle rollers interposed between the raceway surface of the outer ring and the outer peripheral surface of the eccentric shaft, and a retainer for holding the needle rollers at predetermined circumferential intervals, the shaft including the raceway surface of the outer ring Assuming that t is the thickness at the center in the direction and T is the radial dimension between the outer diameter of the axial end and the inner diameter of the flange, T ≦
2.3t, and t ′ ≦ dw / 2, where t ′ is the radial dimension between the inner diameter of the axial center portion and the inner diameter of the flange, and dw is the diameter dimension of the needle roller. It is characterized by the following.

The present invention is further characterized in that the end face of the flange is tapered so as to be inclined inward toward the inner diameter side, and the retainer is guided by the inner diameter face of the flange. It is a feature.

According to the present invention, the area of the lubricating oil inflow port can be made large, the lubricating oil can easily flow into the bearing, and an oil pool is formed at the contact portion between the end face of the flange and the needle roller. The oil sump was filled with lubricating oil.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a shell-type needle roller bearing for a scroll compressor according to the present invention comprises an outer ring 11 made of a thin steel plate fixed to an orbiting scroll member 3, a raceway surface of the outer ring 11 and the eccentric shaft. A plurality of needle rollers 12 interposed between the outer peripheral surfaces of the needle rollers 2 and a retainer 13 for holding the needle rollers 12 at predetermined circumferential intervals.

A flange 11a is formed at both ends in the axial direction of the outer ring 11 by bending the ends of the cylindrical thin steel plate constituting the outer ring 11 toward the inner diameter side.
Thus, the retainer 13 is rotatably provided inside the outer ring 11 with the outer peripheral surface guided by the inner peripheral surface of the flange 11a.

As shown in FIG. 2, the outer race 11 has a radial dimension T between an outer diameter at both axial ends forming the flange 11a and an inner diameter of the flange 11a. And a radial dimension t ′ between the inner diameter of the axial center part and the inner diameter of the flange 11 a is set to be 2.3 times or less the thickness t of the central part in the direction. It is formed so as to be １ ／ or less of the dimension dw.

Further, the end surface 11a 'of the flange 11a is formed as a tapered surface slightly inclined inward toward the inner diameter side. Thereby, the end surface 11a 'of the flange 11a and the needle roller 1
An oil pool 14 that gradually increases toward the outer diameter side is formed at the portion where the oil reservoir 14 comes into contact.

As described above, according to the shell-shaped needle roller bearing of the present invention, the flanges 11 provided at both axial ends of the outer race 11 are provided.
a is folded back toward the inner diameter side, and the radial dimension T between the outer diameter of both ends in the axial direction of the outer ring 11 forming the flange 11a and the inner diameter of the flange 11a is determined by determining the raceway surface of the outer ring 11. The inner diameter of the outer ring 11 is formed to be 2.3 times or less the thickness t of the central portion in the axial direction, and the radial dimension t ′ between the inner diameter of the outer ring 11 at the central portion in the axial direction and the inner diameter of the flange 11a is determined by a needle. By forming the diameter of the roller 12 to be 1/2 or less of the diameter dimension dw, the area of the lubricating oil inlet can be increased, and the lubricating oil can easily flow into the bearing. And Tsuba 1
By forming the end face 11a 'of 1a slightly inclined inward toward the inner diameter side, the oil pool 14 gradually increasing toward the outer diameter side at the contact portion between the end face 11a' of the flange 11a and the needle roller 12 is formed. Was formed, and the lubricating oil was sealed in the oil sump 14. As a result, the supplied lubricating oil can be efficiently and maximally taken in, and since the lubricating oil is collected at the contact portion between the end face 11a 'of the flange 11a and the needle roller 12, good lubrication performance inside the bearing is achieved. And the durability of the bearing can be improved.

The outer edge 1 from the end face 11a 'of the flange 11a.
If the length L leading to 1a "is shortened, the lubricating oil can easily enter the bearing. Therefore, the length L is set to 2.7 times or less the wall thickness t of the outer ring 11 at the central portion in the axial direction. It is preferable to form it.

FIG. 3 shows a lubricating oil: JOMO high speed fluid, a load: 100 kgf, and a lubricating oil for the shell needle bearing (product of the present invention) having the above-described structure and the shell needle bearing (conventional product) shown in FIG. Amount: 325cc /
It shows the result of measuring the amount of oil that has passed through the bearing under the condition of 30 s. As shown in the figure, the product of the present invention shows an excellent amount of oil passing through the bearing as compared with the conventional product.

[0018]

As described above, according to the present invention,
The lubricating oil can be efficiently supplied to the lubricating oil by maximizing the inflow area of the lubricating oil, and the lubricating oil can be accumulated at the contact between the flange end surface of the outer ring and the needle rollers. A shell needle roller bearing for a scroll compressor having excellent lubrication performance in a bearing and durability of the bearing can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing an embodiment of a shell-type needle bearing for a scroll compressor of the present invention.

FIG. 2 is an enlarged sectional view of a main part of an outer race.

FIG. 3 is a diagram showing the relationship between the shaft rotation speed and the amount of oil passing through a bearing for a product of the present invention and a conventional product.

FIG. 4 is a schematic sectional view of a main part showing a general area configuration of the scroll compressor.

FIG. 5 is a sectional view of a main part showing a form of a conventional shell-type needle bearing for a scroll compressor.

[Explanation of symbols]

Reference Signs List 11 outer ring 11a flange 11a 'end surface of flange 11a "outer edge of flange 12 needle roller 13 retainer 14 oil sump T radial dimension between outer diameter at both axial ends of outer ring and inner diameter of flange t outer ring orbit Thickness dimension at the center in the axial direction including the surface t 'Radial dimension between the inner diameter at the center in the axial direction of the outer ring and the inner diameter of the flange dw Diameter of the needle roller L Length from the end face of the flange to the outer edge Size

Claims (3)

[Claims] 1. A shell-type needle roller bearing used in a scroll compressor that performs an operation of compressing a working medium in a compression chamber by eccentrically rotating an orbiting scroll member with respect to a stationary scroll member by eccentric rotation of an eccentric shaft. An outer ring made of a thin steel plate having a flange portion fixed to the orbiting scroll member and formed inwardly at both ends in the axial direction, and between a raceway surface of the outer ring and an outer peripheral surface of the eccentric shaft. A plurality of needle rollers, and a retainer for holding the needle rollers at predetermined circumferential intervals. The thickness of the central portion in the axial direction including the raceway surface of the outer ring is t, The radial dimension between the diameter and the inner diameter of the collar is T
T ≦ 2.3t, and t ′ ≦ dw, where t ′ is the radial dimension between the inner diameter of the axial center portion and the inner diameter of the flange, and dw is the diameter dimension of the needle roller. / 2, a shell needle roller bearing for a scroll compressor, wherein 2. The needle needle roller bearing for a scroll compressor according to claim 1, wherein an end surface of the flange is tapered so as to be inclined inward toward an inner diameter side. 3. The needle needle roller bearing for a scroll compressor according to claim 1, wherein said cage is guided by an inner diameter surface of said flange.