JP2011133062A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing which stabilizes and reduces dynamic friction torque in an early stage at operation start while securing sufficient lubricating performance. <P>SOLUTION: In the rolling bearing 10 having a retainer 14 guided by an inner ring 11 or an outer ring 12, the retainer 14 is impregnated with lubricating oil, and a plurality of grooves extending to an axial direction and a plurality of grooves extended to a circumferential direction are formed on an inside diameter surface or an outside diameter surface 14a as a guide surface of the retainer 14. Thereby, agitating resistance caused by the lubricating oil is reduced, and rolling frictional resistance can be reduced. Further, in an initial stage of rotation, the dynamic friction torque can be suppressed to be low. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an improvement of a rolling bearing, and more specifically to an improvement of a satellite attitude control flywheel rolling bearing and a gyroscope rolling bearing used with a small amount of oil lubrication.

  In order to ensure the durability of rolling bearings for flywheels for artificial satellite attitude control and rolling bearings for gyroscopes, the amount of lubricating oil to be filled when assembling the rolling bearings is minimized and torque fluctuation is minimized. There has been a problem of ensuring good lubrication performance by minimizing the pressure.

  As a prior art for improving this part, there is Patent Document 1: Japanese Patent Application Laid-Open No. 2008-8396, in which a cage is formed of a porous body having continuous air holes embedded with an oil-impregnated cloth material. By impregnating the cloth material and the porous body with a low vapor pressure lubricating oil, it is possible to hold the lubricating oil in the cloth material for a long time without suppressing the scattering of the lubricating oil and increasing the porosity of the porous body. It is intended to ensure good lubrication performance.

JP 2008-8396 A

  However, this prior art has a problem that the lubricating oil stays on the guide surface of the cage and the pocket surface of the cage. The dynamic friction torque accompanying the rotation of the rolling bearing gradually decreases with the passage of time after the start of rotation or the operation of the apparatus incorporating the bearing, and becomes a steady state, and is stabilized at a steady torque value. However, when the lubricating oil stays on the guide surface of the cage or the pocket surface of the cage, a so-called oil jog phenomenon occurs, in which the dynamic friction torque does not decrease due to the retained lubricating oil, which causes the dynamic friction torque. May take a long time to reach a steady value. In such a case, in order to stabilize the dynamic friction torque, a so-called break-in operation takes a long time, and work efficiency becomes extremely low. On the other hand, if the amount of the lubricating oil is too small to avoid such a phenomenon, the guide surface of the cage is not sufficiently lubricated, and the sliding friction between the cage and the guide surface of the raceway is increased. For this reason, there has been a problem that self-excited vibration of the cage is caused and noise may be generated.

  In order to solve the above problems, the present invention provides a rolling bearing provided with a cage guided by an inner ring or an outer ring, wherein the cage is impregnated with lubricating oil, and an inner diameter surface or an outer surface which is a guide surface of the cage. A plurality of grooves extending in the axial direction and grooves extending in the circumferential direction are formed on the radial surface.

  According to the present invention, the lubricating oil is appropriately drained to the outside by the axial and circumferential grooves provided on the guide surface, and does not stay in the guide surface or pocket. For this reason, it can be avoided that it takes a long time to stabilize the dynamic friction torque due to the oil jog phenomenon or the like, and it is not necessary to take a long time for the running-in operation of the rolling bearing. In addition, since a minimum amount of lubricating oil is appropriately retained in the axial and circumferential grooves, good lubricating performance can be ensured between the cage and the raceway, and noise can be generated. Can also be reduced.

It is a fragmentary sectional view which shows the angular ball bearing of this invention. It is a figure which shows the holder | retainer concerning this invention.

  Hereinafter, an example of an embodiment of the present invention will be described based on the drawings. FIG. 1 shows an angular ball bearing 10 that can be used in an artificial hygiene posture control flywheel or a gyroscope. The angular ball bearing 10 is provided with an inner ring 11, an outer ring 12, a plurality of rolling elements (balls) 13 arranged between the inner ring and the outer ring, and pockets 15 for holding the balls 13 at equal intervals in the circumferential direction. Is impregnated with the cage 14.

  The outer diameter surface 14 a of the cage 14 is a guide surface that is guided by the outer ring 12. The lubricating oil is supplied to the gap between the outer diameter surface 14a and the inner diameter surface of the outer ring 12, so that sliding friction is suppressed.

  As shown in FIG. 2A, an axial groove 16 extending in the cage axial direction and a circumferential groove 17 extending in the circumferential direction are formed on the outer diameter surface 14 a of the cage 14. The axial direction groove | channel 16 and the circumferential direction groove | channel 17 are each recessedly provided in the outer-diameter surface 14a so that it may have depth in the radial direction of the holder | retainer 14, and cross-sectional shape is a semicircle shape.

  The axial grooves 16 are provided between the pockets 15 adjacent to each other on the outer diameter surface 14 a of the retainer 14 (hereinafter also referred to as column portions) and at positions corresponding to the circumferential positions of the pockets 15. Adjacent axial grooves 16 are provided at regular intervals in the circumferential direction. The circumferential groove 17 is provided at the center of the pillar in the cage axial direction, and is configured such that adjacent pockets 15 communicate with each other in the circumferential direction through a space in the groove. In the column portion, the axial groove 16 and the circumferential groove 17 are perpendicular to each other and communicate with each other.

  According to the configuration of the present embodiment, since the axial groove 16 and the circumferential groove 17 are provided on the outer diameter surface 14a that is the guide surface of the retainer 14 guided by the outer ring 12, a minimum amount of lubrication is provided. Excess lubricating oil can be efficiently discharged from the axial groove 16 and the circumferential groove 17 to the outside while securing the oil on the outer diameter surface 14a. For this reason, at the time of rotation in the angular ball bearing 10, the stirring resistance caused by the lubricating oil can be reduced, the rolling friction resistance can be reduced, and the dynamic friction torque can be kept low in the initial operation. Since excess lubricating oil does not stay in the outer diameter surface 14a and the pocket 15 of the cage 14, the time from the start of operation of the angular ball bearing 10 to the steady value can be significantly shortened. Further, since a minimum amount of lubricating oil is appropriately secured in the axial groove 16 and the circumferential groove 17 provided on the outer diameter surface 14a of the cage 14, the friction on the guide surface of the cage 14 can be reduced, Generation of self-excited vibration and noise of the cage 14 can be prevented.

  FIG. 2 (b) shows another embodiment of the present invention. The cage 24 is a machined cage that is incorporated in a cylindrical roller bearing. The cage 24 has pockets 25 in which rollers (not shown) are loaded at equal intervals in the circumferential direction, and is impregnated with lubricating oil. On the outer diameter surface 24a of the cage 24, an axial groove 26 extending in the cage axial direction and a circumferential groove 27 extending in the circumferential direction are formed.

  The axial grooves 26 are provided between the pockets 25 adjacent to each other on the outer diameter surface 24 a of the retainer 24 (hereinafter also referred to as a column portion) and at positions corresponding to the circumferential positions of the pockets 25. Adjacent axial grooves 26 are provided at regular intervals in the circumferential direction. The circumferential groove 27 is provided in the center of the pillar in the cage axial direction, and is configured such that adjacent pockets 25 communicate with each other in the circumferential direction through a space in the groove. In addition, the dimensions and shapes of the axial groove 26 and the circumferential groove 27 are the same as those shown in FIG.

  In the embodiment described above, the outer diameter surfaces 14a and 24a are provided with grooves. However, in the case of a rolling bearing with an inner ring guide, the grooves may be provided on the inner diameter surface of the cage. In this way, the same effect as the above embodiment can be obtained.

  In addition, this invention is not limited to embodiment mentioned above, A suitable deformation | transformation, improvement, etc. are possible. The present invention can be applied not only to ball bearings and cylindrical roller bearings, but also to general rolling bearings having a cage, such as tapered roller bearings, needle bearings, and self-aligning bearings, and has a remarkable effect. The axial groove may be provided only in the pillar portion of the cage, or may be provided only at a position corresponding to the pocket. The circumferential groove may be circulated not only on the column part but also on both sides in the axial direction of the pocket. The dimensions and shapes such as the depth and width of the axial grooves and the circumferential grooves can be freely set within a range where the effects of the present invention can be achieved. For example, the cross-sectional shape may be a square shape, a rectangular shape, or a triangular shape in addition to a semicircular shape.

  Further, the bearing may be used in a state where an oil plating process is applied in which a small amount of lubricating oil is applied to the outer ring raceway and inner ring raceway of the bearing and the surface of the rolling element.

  The present invention can be used as a rolling bearing, specifically, a flywheel rolling bearing for satellite attitude control and a gyroscope rolling bearing used with a small amount of oil lubrication.

10 Angular Contact Ball Bearing 11 Inner Ring 12 Outer Ring 13 Rolling Element (Ball)
14 Retainer 15 Pocket 16 Axial groove 17 Circumferential groove 24 Retainer 25 Pocket 26 Axial groove 24 Retainer 25 Pocket 26 Axial groove 27 Circumferential groove

Claims (1)

  In a rolling bearing provided with a cage guided by an inner ring or an outer ring, the cage is impregnated with lubricating oil, and a groove extending in the axial direction and a circumferential direction are provided on an inner diameter surface or an outer diameter surface which is a guide surface of the cage. A rolling bearing characterized in that a plurality of grooves extending in the groove are formed.

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