JPH102326A - Composite bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a roller bearing to simplify structure, support both radial and thrust loads, and be used up to high speed rotation. SOLUTION: In a roller bearing using a ball or a roller 3, a herringbone groove 5 is formed in the side of a retainer 4 to support the ball or the roller 3. Inner and outer rings 1 and 2 form a ring with a rib and a thrust dynamic pressure bearing comprises the side of the retainer 4; the rib part of the inner ring 2; and an outer ring rib part, and the ball or the roller are constituted to have a structure to support only a load in a radial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling bearing of a composite type capable of supporting a radial load and a thrust load in a rolling bearing which uses a rolling element to support the rolling.

[0002]

2. Description of the Related Art In a conventional radial roller bearing, a plurality of rollers separated and held by a retainer are held by being separated and aligned by a retainer between an inner ring and an outer ring. Rolled on the surface and the inner peripheral surface of the outer ring, and rotated while supporting mainly the load in the radial direction.

[0003]

In the case of a conventional roller bearing, it is possible to support a load only in the radial direction, and when a thrust load is to be received, a separate thrust bearing must be provided. There was a problem that the number of points increased and the structure became complicated. Angular bearings that use tapered rollers as rolling elements are used to avoid this and receive a radial load and a thrust load by one bearing, but the shape is complicated and high-precision machining is not possible, and there is a limit in rotational accuracy. And that the number of revolutions cannot be increased. Further, there is an angular bearing in which the ball is sandwiched between inclined rolling surfaces, but the rigidity is small and it is difficult to receive a large thrust load.

[0004]

Means for Solving the Problems In a roller bearing, a flange portion is provided on the side surface of the inner ring of the bearing from the outer peripheral surface to the outside, and a flange portion is provided on the side surface of the outer ring from the inner peripheral surface thereof to support the roller. Forming a herringbone groove or tapered step on both sides of the retainer
Fluid dynamic pressure bearings are formed on the flanges of the inner ring and the outer ring and on both side surfaces of the retainer to form thrust bearings. Alternatively, spiral grooves are formed on both side surfaces of the roller, and the side surfaces of the outer ring and the inner ring form a dynamic pressure bearing.

[0005]

[Action]

[0006] Since the radial load is supported by rollers and the thrust load is supported by a thrust bearing formed by the side surfaces of the retainer and the flange surfaces of the inner ring and the outer ring, it is possible to support both the radial load and the thrust load by one piece. it can.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 shows a composite bearing of the present invention, in which an outer ring 1 is provided with a flange portion 8 extending inward on a side surface thereof, and an inner ring 2 is provided with a flange portion 9 extending outward on a side surface thereof. Between the inner peripheral surface of the outer race 1 and the outer peripheral surface of the inner race 2, a number of rollers 3 separated and held by a retainer 4 are inserted. The thickness of the retainer 4 holding the roller 3 is slightly smaller than the diameter of the roller, and herringbone grooves are formed on both side surfaces as shown in FIG. The directions of the herringbone grooves on both sides of the retainer 4 are opposite to each other. The retainer 4 has one side surface facing the flange portion 8 of the outer ring, and the other side surface facing the flange portion 9 of the inner ring, between which a lubricating fluid is filled to constitute a dynamic pressure bearing. Now, when the shaft (not shown) rotates and the inner ring 2 fitted thereto rotates in the direction of arrow a shown in FIG. 2, the roller 3 rotates and rolls on the inner surface of the outer ring. Along with this, the retainer 4 also rotates around the inner ring in the direction of arrow b shown in FIG. The rotation speed of the retainer 4 at this time is about half of the rotation speed of the inner ring. Therefore, the retainer side surface and the flange portion 8 of the outer ring and the retainer side surface and the flange portion 9 of the inner ring have a relative speed, and a dynamic pressure is generated by the flow of the fluid. This force supports the thrust force. Since the load in the radial direction is supported by the roller, the load in both the radial and thrust directions can be supported by one bearing. The same applies to the case where the inner ring is fixed and the outer ring rotates. FIG. 2 shows an example in which a tapered step is provided on the side surface of the retainer 4 instead of the herringbone groove. In this case, a dynamic pressure is generated by the wedge effect of the fluid, and the thrust load is supported.

FIG. 3 shows a second embodiment of the present invention.
In the case of the embodiment, the direction of the thrust load that can be supported is limited to one direction in which the flange surfaces press against each other, but the thrust load can be supported in both directions. A central flange portion 25 is provided on the inner ring 22.
3 ′, retainers 4, 4 ′ and outer rings 1, 1 ′ are pressed and pressed. The operation is the same as in the first embodiment. In the present embodiment, it is possible to receive a thrust load in two left and right directions.

FIG. 4 shows a third embodiment of the present invention, in which balls are used instead of rollers. This is effective when the radial load is small and it is desired to reduce the rolling friction of the bearing. A rolling groove 37 for rolling the ball is formed in the inner race 32, and the ball 33 is supported by a retainer 34 having a tapered step or a herringbone groove formed on both end surfaces so as to roll in the groove. Inner ring 32 and outer ring 3
1 are formed with flange portions 39 and 38, respectively.
A side surface of the retainer 34 and a thrust dynamic pressure bearing are formed. In this case, only radial loading acts on the ball,
Since there is no inclination of the contact surface for receiving the thrust force and no gyro moment acts on the ball, there is no sliding between the ball and the rolling surface, and the life is extended. Other effects are the same as those of the first embodiment.

FIG. 5 shows a fourth embodiment of the present invention. In the case of the first and second embodiments, since the roller is wrapped in the retainer in the axial direction, the length of the retainer is longer than that of the roller. As a result, the overall length of the bearing is longer, so that a smaller space is required. Suitable when you want to use with. Rollers 23 having spiral grooves formed on both sides as shown in FIG. 7 are held by cages 24 as shown in FIG. 6, and directly constitute the thrust dynamic pressure bearings with the flange portions 16 and 17 of the outer ring 11 and the inner ring 12. . The cage 14 is a thin plate made of metal or plastic having a cross section shown in FIG. 6 and has both ends in the gap between the inner ring 2 and the outer ring 1. Since the roller 23 also rotates with the rotation of the inner ring 2 or the outer ring 1, a dynamic pressure is generated on the side surface, and the thrust load is supported. In this case, there is an effect that the bearing can be downsized.

[0012]

According to the present invention, a single bearing can support a radial load and a thrust load.

[Brief description of the drawings]

FIG. 1 is a sectional perspective view of a main part of a composite bearing according to a first embodiment of the present invention.

FIG. 2 is a sectional perspective view of a main part of a composite bearing according to a modification of the first embodiment of the present invention.

FIG. 3 is a sectional view of a main part of a composite bearing according to a second embodiment of the present invention.

FIG. 4 is a sectional perspective view of a main part of a composite bearing according to a third embodiment of the present invention.

FIG. 5 is a sectional perspective view of a main part of a composite bearing according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view of a main part of a composite bearing according to a fourth embodiment of the present invention.

FIG. 7 is a spiral groove diagram of a roller end face according to a fourth embodiment of the present invention.

[Explanation of symbols]

1, 1 ', 31 Outer ring 2, 22, 32 Inner ring 3, 3', 13, 23 Roller 4, 14, 34 Retainer 8, 8 ', 9, 18, 28, 38, 39 Flange 5, Herringbone groove 15 , 15 'Tapered step 24 Cage 25 Spiral groove 26 Central flange 33 Ball 37 Ball rolling groove

Claims (2)

[Claims] In a rolling bearing in which a roller or a ball rolls on an outer peripheral surface of an inner ring and an inner peripheral surface of an outer ring as a rolling element, the thickness of a retainer holding the roller or the ball is made slightly smaller than the diameter of the rolling element held by the roller. A herringbone groove or a tapered step is formed on the inner ring, a flange portion is provided on the inner ring from the outer peripheral surface to the outer side, and a flange portion is provided on the outer ring from the inner peripheral surface on the inner side. A composite bearing comprising a fluid dynamic pressure bearing on both sides. 2. A rolling bearing in which a roller as a rolling element rolls on an outer peripheral surface of an inner race and an inner peripheral surface of an outer race. A composite bearing, wherein a flange portion is provided inside the inner peripheral surface, and fluid dynamic pressure bearings are formed on the flange portions of the inner ring and the outer ring and on both side surfaces of the roller.