JP2016023707A - Self-aligning roller bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a self-aligning roller bearing for preventing the damage of the surface of a guide ring at a low cost.SOLUTION: A self-aligning roller bearing 1 comprises: an inner ring 2; an outer ring 3; a plurality of rollers 4 arranged in freely rolling manners between double rows of orbital planes 2a and 3a; and a guide ring 6 arranged between the rows of the rollers 4 and 4 for guiding the rollers 4. The side faces of the guide ring 6 have the inclined planes 6 which are so inclined with an opening at an opening angle θ as to leave the axial end face of the rollers 4 against the directions of forces applied from the rollers 4 to the inner ring 2. A dull part 4c is formed in a chamfer part 4b chamfered in the end face 4a of the axial direction of the rollers 4.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a self-aligning roller bearing.

  Conventionally, as shown in FIG. 5A, a self-aligning roller bearing used in an industrial machine or the like has an inner ring 101 having double-row raceway surfaces 101a and 101a on an outer peripheral surface, and an inner ring 101 on an inner peripheral surface. An outer ring 102 having a spherical raceway surface 102a facing the raceway surface 101a, and a plurality of rollers 103 that are rotatably arranged between the inner ring 101 and the double-row raceway surfaces 101a, 102a of the outer ring 102 are provided. .

  In such a self-aligning roller bearing 100, in many cases, the guide wheels 105 for guiding the axial end surfaces of the rollers 103 are provided on the rollers 103 and 103 so that the double row rollers 103 can roll without skew. Arranged between columns. In other words, the guide wheel 105 has a sliding surface 105 a that slidably contacts the sliding surface 101 b of the inner ring 101. Further, the guide wheel 105 has a side surface 105b that is slidably in contact with the axial end surfaces 103a and 103a of the rollers 103 and 103, respectively.

Such a self-aligning roller bearing has a purpose of preventing wear of the guide wheel by forming an oil film between the guide wheel and the like. Examples of this type of self-aligning roller bearing include those disclosed in Patent Document 1 and Patent Document 2.
The technique disclosed in Patent Document 1 increases the number of rotations of the guide wheel as an inner ring drive by reducing the gap between the guide wheel and the inner ring, increases the sliding speed with the roller, and forms an oil film to guide the wheel. It is intended to prevent the wear of the ring.
In addition, the technology disclosed in Patent Document 2 is configured to prevent the occurrence of galling by providing an inclined surface on the guide ring so as to open to the inner ring side, thereby preventing adhesion between the side surface of the roller and the entire side surface of the guide wheel. It is what has.

Japanese Patent No. 3789698 JP 2000-65052 A JP 2007-278494 A

However, the technique disclosed in Patent Document 1 has a problem that an oil film having a sufficient thickness cannot be formed if the guide wheel surface has a large roughness.
As shown in FIG. 5 (b), when the roller 103 comes into contact with the boundary 105e, which is the boundary between the chamfered portion 105d on the inner diameter side of the guide wheel 105 and the side tapered portion 105c, the boundary 105e and the axis of the roller 103 The end surface 103a in the direction and the boundary between the chamfered portion 103 and the chamfered portion are in contact with each other (indicated by a dotted circle). As a result, the oil film held between the roller 103 and the guide wheel 105 becomes thin, which is disadvantageous for oil film formation, and is insufficient to prevent the surface 105b of the guide wheel 105 from being damaged.

Further, when the shape of the end surface 103a in the axial direction of the roller 103 is spherical and the end surface 103a and the side taper portion 105c are in surface contact, the contact area is expanded, and the oil film held between the roller 103 and the guide wheel 105 is thin. Therefore, it is disadvantageous for oil film formation, and is insufficient to prevent damage to the surface of the guide wheel.
Also in the technique disclosed in Patent Document 2, if the roughness of the side surface of the guide wheel is large, an oil film may not be formed sufficiently, and as a result, there is a slight possibility that galling will occur and there is room for improvement. there were.
Therefore, Patent Document 3 is disclosed as a technique for reducing the sliding friction coefficient of the surface by providing a shot peening layer, a DLC layer, and a ceramic layer on the side surface of the guide wheel to prevent damage to the side surface of the guide wheel. Yes.

However, in the technique disclosed in Patent Document 3, there is a cost for providing a shot peening layer, a DLC layer, and a ceramic layer on the surface (side surface) of the guide wheel, which may increase the cost of the product. It was.
The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a self-aligning roller bearing that can prevent damage to the surface of the guide wheel at low cost.

A certain aspect of the self-aligning roller bearing for solving the above problems is an inner ring having a double-row raceway surface on the outer peripheral surface, and an outer ring having a spherical raceway surface facing the raceway surface on the inner peripheral surface, A plurality of rollers arranged to roll freely between the raceways of the double row, and a guide wheel arranged between the rows of the rollers to guide the rollers,
A side surface of the guide ring has an inclined surface that is opened and inclined toward the outer ring side at an opening angle θ so as to be separated from the axial end surface of the roller with respect to the direction of the force applied from the roller to the inner ring. And
The slack portion is provided in the chamfered portion chamfered at the axial end surface of the roller.

In the self-aligning roller bearing, it is preferable that the surface roughness Rmax of the side surface of the guide wheel measured according to JIS B 0601 is 6 s or less.
In the self-aligning roller bearing, it is preferable that the end surface of the roller is a flat surface and the opening angle θ is 0.5 ° to 3.0 °.
In the self-aligning roller bearing, it is preferable that the end face of the roller has a spherical shape and the opening angle θ is 2.0 ° to 3.5 °.
In the self-aligning roller bearing, it is preferable that the swaying portion is provided so that a boundary between the inclined surface of the guide wheel and the end surface in the axial direction of the roller and the splaying portion are in contact with each other.

  ADVANTAGE OF THE INVENTION According to this invention, the self-aligning roller bearing which prevents damage to the surface of a guide wheel at low cost can be provided.

It is sectional drawing which shows the structure in 1st Embodiment of the self-aligning roller bearing of this invention. It is a principal part enlarged view of FIG. It is sectional drawing which shows the structure in 2nd Embodiment of the self-aligning roller bearing of this invention. It is a principal part enlarged view of FIG. It is sectional drawing which shows the conventional structure of a self-aligning roller bearing.

Hereinafter, embodiments of a self-aligning roller bearing according to the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a cross-sectional view showing the configuration of a self-aligning roller bearing according to a first embodiment of the present invention. 2A is an enlarged view of a main part of FIG. 1, and FIG. 2B is an enlarged view of a main part of FIG. 2A and 2B are slightly exaggerated for the sake of understanding.
As shown in FIG. 1, the self-aligning roller bearing 1 of the present embodiment includes an inner ring 2 having double-row raceway surfaces 2 a on the outer peripheral surface, and a spherical raceway facing the raceway surface 2 a of the inner ring 2 on the inner peripheral surface. An outer ring 3 having a surface 3a and a plurality of rollers 4 arranged to roll freely between the double-row raceway surfaces 2a and 3a are provided.

The roller 4 of the self-aligning roller bearing 1 is held by a cage 5 so as to roll freely for each roller row. An annular guide wheel 6 is arranged between the axial center portion 2 b on the outer peripheral surface of the inner ring 2 and the inner peripheral surface of the cage 5.
The guide wheel 6 has an inner peripheral surface (sliding surface) 6 a in sliding contact with the axial center portion 2 b on the outer peripheral surface of the inner ring 2, and an outer peripheral surface 6 f in sliding contact with a part of the inner peripheral surface of the cage 5. It is like that. The lubricating oil is held between the side surface 6b of the guide wheel 6 and the axial end 4a of the four to form a fluid film.

[Opening angle]
Here, the side surface 6b of the guide ring 6 of the self-aligning roller bearing 1 is separated from the end face 4a in the axial direction of the roller 4 with respect to the straight line L indicating the direction of the force applied from the roller 4 to the inner ring 2. An inclined surface 6c that is opened and inclined toward the outer ring side at an opening angle θ is formed. The opening angle θ is defined as an angle formed by the surface S1 including the inclined surface 6c of the guide wheel 6 and the straight line L indicating the direction of the force applied from the roller 4 to the inner ring 2 with respect to the contact angle δ. .
The “contact angle” is defined by the contact angle “nominal contact angle” described in Japanese Industrial Standards JIS B 0104-1991 “Rolling Bearing Terms”, and the surface S2 orthogonal to the bearing central axis; It means an angle δ formed by a straight line L indicating the direction of the force applied from the roller to the inner ring.

  The opening angle θ is preferably 0.5 ° to 3.0 ° when the shape of the end surface 4a of the roller 4 is a flat surface. When the opening angle θ is smaller than 0.5 °, the end face 4a in the axial direction of the roller 4 and the “boundary 6cg between the parallel part 6g of the guide wheel 6 and the inclined surface 6c” are likely to hit when the roller 4 is skewed. As a result, the boundary 6cg is easily damaged. On the other hand, when the opening angle θ exceeds 3.0 °, the rollers 4 are likely to skew, which is not preferable. The opening angle θ is more preferably 1.5 °.

[Looseness]
On the other hand, the chamfered portion 4b chamfered on the end surface 4a in the axial direction of the roller 4 of the self-aligning roller bearing 1 is provided with a slack portion 4c. The slack portion 4c indicates a shape that is less than the change in the radial curvature of the chamfered portion 4b or is cut to the chamfered portion 4b with the dimension d in a zero state. The formation of the slack portion 4c is, for example, turning. The dimension d is preferably about 1 mm to 2 mm. If the dimension d is smaller than 1 mm, the “boundary 6e between the inclined surface 6c of the guide wheel 6 and the chamfered portion 6d” and the “boundary 4ac between the end surface 4a in the axial direction of the roller 4 and the sloping portion 4c” are likely to hit. . If the dimension d exceeds 2 mm, the boundary 4ac of the roller 4 and the “boundary 6cg between the parallel portion 6g of the guide wheel 6 and the inclined surface 6c” are likely to hit. That is, the dimension d is preferably set to a size such that the boundary 4ac of the roller 4 hits the inclined surface 6c of the guide wheel 6. The dimension d is measured in a direction perpendicular to the central axis of the roller 4.
[Surface roughness of the guide wheel side]
Here, the roughness of the side surface 6b of the guide wheel 6 of the self-aligning roller bearing 1 is preferably 6 s or less in the surface roughness Rmax measured according to JIS B 0601.

(Second Embodiment)
Next, a second embodiment of the self-aligning roller bearing will be described with reference to the drawings. FIG. 3 is a cross-sectional view showing a configuration in a second embodiment of the self-aligning roller bearing of the present invention. 4A is an enlarged view of a main part of FIG. 3, and FIG. 4B is an enlarged view of a main part of FIG. 4A. 4A and 4B are slightly exaggerated for the sake of understanding. The self-aligning roller bearing 1 of the present embodiment has substantially the same configuration as that of the first embodiment except for the shape of the rollers 4 and the set angle of the opening angle θ. Hereinafter, the same components as those in the first embodiment will be denoted by the same reference numerals, description thereof will be omitted or simplified, and different configurations will be mainly described.

  As shown in FIGS. 3 and 4 (a), 4 (b), the self-aligning roller bearing 1 has a spherical cross-sectional shape of the end face in the axial direction of the roller 4. In the self-aligning roller bearing 1 employing the roller 4 having such a cross-sectional shape, it is preferable that the opening angle θ is about 2.0 ° to 3.5 °. When the opening angle θ is smaller than 2.0 °, the inclined surface 6c of the guide wheel 6 and the end surface 4a of the 4 are likely to hit, and the inclined surface 6c is easily damaged. On the other hand, when the opening angle θ exceeds 3.5 °, the rollers 4 are likely to skew, which is not preferable.

As described above, the self-aligning roller bearing 1 of the present embodiment has the guide wheel 6 formed with the inclined surface 6c, and the end surface 4a of the roller 4 is provided with the slack portion 4c. Since the boundary 4ac ”and the inclined surface 6c are brought into contact with each other to form an oil film having a sufficient thickness, damage to the side surface 6b of the guide wheel 6 can be prevented.
Moreover, since the self-aligning roller bearing 1 of this embodiment performs the conventional turning process with respect to the roller 4 and the guide wheel 6, the self-aligning roller bearing which reduced the factor of the cost increase can be provided. .
The spherical roller bearing according to the present invention has been described above. However, the spherical roller bearing according to the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. Is possible.

DESCRIPTION OF SYMBOLS 1 Self-aligning roller bearing 2 Inner ring 3 Outer ring 4 Roller 4a (Axial direction) end face 4b Chamfered part 4c Slapping part 4ac Boundary 5 Cage 6 Guide wheel 6a Sliding surface 6b Side face 6c Inclined surface 6d Chamfered part 6g Parallel part 6cg

Claims (2)

An inner ring having a double-row raceway surface on the outer peripheral surface, an outer ring having a spherical raceway surface facing the raceway surface on the inner peripheral surface, and a plurality of rolls disposed between the double-row raceway surfaces in a freely rotatable manner. A roller and a guide wheel disposed between the rows of rollers to guide the roller;
A side surface of the guide wheel has an inclined surface that is opened and inclined toward the outer ring side at an opening angle θ so as to be separated from the end surface in the axial direction of the roller with respect to the direction of the force applied from the roller to the inner ring. And
A self-aligning roller bearing characterized in that a sloping portion is provided in a chamfered portion chamfered at an end surface in the axial direction of the roller.   The self-aligning roller bearing according to claim 1, wherein a surface roughness Rmax of the side surface of the guide wheel measured according to JIS B 0601 is 6 s or less.

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