JP2007071292A - Roller bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce torque loss due to viscous resistance accompanying with dragging-in of lubricating oil in a roller bearing. <P>SOLUTION: A V-groove 1b being continuous in the circumferential direction in one section in a central part in the axial direction is provided on a rolling face 1a of a cylindrical roller 1, and lubricating oil dragged into a contact part from a wedge space is made to escape onto both sides of divided rolling contact region by dividing a wide rolling contact region of the rolling face 1a of the cylindrical roller 1 and each raceway surface 2a, 3a of inner and outer rings 2, 3 in the axial direction to reduce torque loss due to viscous resistance accompanying with dragging-in of lubricating oil. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a roller bearing.

  Reducing the torque cross associated with the rotation of rolling bearings has been an eternal issue, and various efforts have been made to improve lubricating oil and lubrication conditions. Therefore, further reduction of the torque cross is required.

  Among rolling bearings, in roller bearings such as cylindrical roller bearings, tapered roller bearings, needle roller bearings, and self-aligning roller bearings, the rolling surface of the roller and the raceway surface of at least one of the inner and outer rings are shafts. Rolling contact in a wide contact area in the direction.

  In a roller bearing in which the rolling surface of the roller and the raceway surface of the raceway are in rolling contact in a wide contact area, the lubricating oil is drawn into the contact portion from a wedge space formed on the entry side of the contact area. The amount of the lubricating oil drawn in increases as the bearing rotates faster, and in a roller bearing that rotates at a high speed, the viscous resistance accompanying the drawing of the lubricating oil becomes a cause of torque loss that cannot be ignored.

  Accordingly, an object of the present invention is to reduce torcross due to viscous resistance accompanying the drawing of lubricating oil in a roller bearing.

  In order to solve the above-described problems, the present invention provides a roller bearing in which a rolling contact surface of a roller and a raceway surface of at least one of the inner and outer rings make rolling contact, and the rolling contact surface of the roller in contact with the rolling contact. Alternatively, a concave groove continuous in the circumferential direction is provided on the raceway surface of at least one of the inner and outer races in the axial direction, and the rolling contact between the rolling surface of these rollers and the raceway surface of the raceway is provided. A configuration was adopted in which the region was divided at at least one axial position.

  That is, the rolling surface of the roller that makes rolling contact or the raceway surface of at least one of the inner and outer races is provided with a concave groove that continues in the circumferential direction at least at one location in the axial direction. By dividing the wide rolling contact area with the raceway surface of the ring at at least one point in the axial direction, the lubricating oil drawn into the contact portion from the wedge space is released to both sides of the divided rolling contact area, It was made possible to reduce torcross due to viscous resistance accompanying pull-in.

  Lubricating oil drawn into the contact portion from the wedge space is divided by providing a convex crowning in the divided rolling contact area on the rolling surface of the roller provided with the concave groove or the raceway surface of the bearing ring. It can be made easier to escape to both sides of the rolling contact area.

  By providing the concave groove on the rolling surface of the roller, it is possible to escape to both sides of the rolling contact region where the lubricating oil is divided in the rolling contact regions on both sides of the inner and outer rings.

  The roller bearing of the present invention is provided with a concave groove continuous in the circumferential direction at least in one axial direction on the raceway surface of at least one of the raceway surface of the roller that makes rolling contact or the inner and outer races. Since a wide rolling contact area between the rolling surface and the raceway surface of the bearing ring is divided at at least one position in the axial direction, the rolling contact area of the lubricating oil drawn from the wedge space to the contact portion is divided. Escape to both sides, and torcross due to viscous resistance associated with the pulling of the lubricating oil can be reduced.

  By providing a convex crowning at the divided rolling contact area on the rolling surface of the roller provided with the concave groove or the raceway surface of the bearing ring, the lubricating oil drawn into the contact portion from the wedge space is divided. It can be made easier to escape to both sides of the dynamic contact area.

  By providing the concave groove on the rolling surface of the roller, it is possible to escape to both sides of the rolling contact region where the lubricating oil is divided in the rolling contact regions on both sides of the inner and outer rings.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a first embodiment. This roller bearing is a cylindrical roller bearing in which the rolling surface 1 a of the cylindrical roller 1 and the raceway surfaces 2 a and 3 a of the inner ring 2 and outer ring 3 are in rolling contact with each other. An obtuse V-groove 1b as a concave groove continuous in the circumferential direction is provided at one central portion of the roller, and the rolling contact between the rolling surface 1a of the cylindrical roller 1 and the raceway surfaces 2a, 3a of the inner and outer rings 2, 3 The region is divided at one place in the axial direction, and a convex crowning 1c is provided on the rolling surface 1a of the cylindrical roller 1 in the divided rolling contact region.

  FIGS. 2A and 2B show the second and third embodiments, respectively. In the second embodiment of FIG. 2A, the rolling groove 1a of the cylindrical roller 1 is provided with V grooves 1b at two locations in the axial direction, and the third embodiment of FIG. 2B. Are provided with V-grooves 1b at three equal positions in the axial direction, and in each of the divided rolling contact regions, a crowning 1c is provided on the rolling surface 1a of the cylindrical roller 1.

The cylindrical roller bearing shown in FIG. 1 (Example 1), the cylindrical roller bearings shown in FIGS. 2A and 2B (Examples 2 and 3), and the entire rolling surface of the cylindrical roller have a convex crowning shape. For the conventional cylindrical roller bearing (comparative example) in which the raceway surface of the inner and outer rings is a flat bus bar shape, the torque cross due to the viscous resistance of the lubricating oil to the rolling of one roller accompanying these rotations was calculated. In addition, the crowning shapes of the cylindrical rollers of the examples and the comparative examples were designed so that the elastic displacement amounts due to contact were equal to each other, and the respective stiffnesses were the same. The calculation conditions are as follows.
Cylindrical roller bearing: Roller diameter 5 mm, roller width 5 mm, pitch circle diameter 55 mm
・ Rotation speed: 2000rpm
・ Contact load: 1000N
・ Lubricant: Automotive gear oil

  FIG. 3 shows the calculation result of the torcross. The torque cross of each Example was represented by the torque cross ratio which set the thing of the comparative example to 1.0. In the example 1 in which the V-groove is provided at one place, the torque cross is reduced by about 10% as compared with the comparative example. Further, as the number of V-grooves is increased, the number of torcross decreases, and in the example 3 in which the V-grooves are provided at three places, the torcross is reduced by about 20%. These results show that by dividing the rolling contact area between the rollers and the inner and outer rings with V-grooves, the lubricating oil escapes to both sides of the divided rolling contact area and the viscous resistance of the lubricating oil drawn into the contact portion is reduced. It is thought that it became small.

  FIG. 4 shows a fourth embodiment. In this roller bearing, in order to divide the rolling contact area, each raceway surface 2a, 3a of the inner ring 2 and the outer ring 3 is provided with V grooves 2b, 3b at one central position in the axial direction, and the divided rolling Crowning 2c, 3c is provided on each raceway surface 2a, 3a of the inner and outer rings 2, 3 in the contact area. Other parts are the same as those of the first embodiment.

  FIGS. 5A and 5B show the fifth and sixth embodiments, respectively. In the fifth embodiment shown in FIG. 5 (a), the raceway surfaces 2a and 3a of the inner and outer rings 2 and 3 are provided with V-grooves 2b and 3b at two locations in the axial direction, FIG. 5 (b). In the sixth embodiment, V-grooves 2b and 3b are equally provided at three locations in the axial direction, and in each of the divided rolling contact regions, the crowning 2c is provided on each raceway surface 2a and 3a. 3c are provided.

  In each of the above-described embodiments, the concave groove that divides the rolling contact region is an obtuse V-shaped groove, but this concave groove may be any one that can be divided by forming a gap in the middle of the rolling contact region. It can be of any shape such as a groove, round groove, rectangular groove or the like. In addition, when a groove edge becomes steep, it is desirable to give roundness to a groove edge part.

  Further, in each of the above-described embodiments, the crowning is provided in each of the divided rolling contact areas on the rolling surface of the roller provided with the concave groove or the raceway surface of the raceway, but these crowning may be omitted. it can.

  Further, in each of the embodiments described above, the roller bearing is a cylindrical roller bearing, but the roller bearing according to the present invention is also applicable to other roller bearings such as a tapered roller bearing, a needle roller bearing, and a self-aligning roller bearing. It can also be applied to double row roller bearings.

Longitudinal sectional view showing the roller bearing of the first embodiment a and b are longitudinal sectional views showing the roller bearings of the second and third embodiments, respectively. Graph showing the calculation result of tolcloth Longitudinal sectional view showing a roller bearing of a fourth embodiment a and b are longitudinal sectional views showing the roller bearings of the fifth and sixth embodiments, respectively.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylindrical roller 1a Rolling surface 2 Inner ring 3 Outer ring 2a, 3a Raceway surface 1b, 2b, 3b V groove 1c, 2c, 3c Crowning

Claims (3)

  In a roller bearing in which the rolling surface of the roller and the raceway surface of at least one of the inner and outer rings are in rolling contact, the rolling surface of the roller in contact with the rolling contact or the raceway surface of at least one of the inner and outer rings In addition, a concave groove continuous in the circumferential direction is provided at at least one location in the axial direction so that the rolling contact area between the rolling surface of these rollers and the raceway surface of the raceway is divided at at least one location in the axial direction. A roller bearing characterized by that.   2. The roller bearing according to claim 1, wherein a convex crowning is provided in the divided rolling contact region on a rolling surface of the roller provided with the concave groove or a raceway surface of the race.   The roller bearing according to claim 1, wherein the concave groove is provided on a rolling surface of the roller.

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