JP2008196589A - Self-aligning roller bearing for planetary reduction gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a self-aligning roller bearing for a planetary reduction gear capable of suitably lubricating a guide surface without damaging a pillar part of a retainer. <P>SOLUTION: The retainer 5 is formed of flexible resin, and an outer diameter surface of its annular part 5a is guided by an inner diameter surface of an outer ring 3. Thereby, the retainer 5 assembled on the inner ring 2 is elastically deformed so as to be flat in a diameter direction, and can be inserted at a right angle so as not to abut on an end of a track surface 3a of the recessed outer ring 3 without providing a cutoff on a vertical part of the outer diameter surface of the annular part 5a as the guide surface. Thus, the bearing can suitably lubricate without damaging the pillar part 5b of the retainer 5, and causing oil film shortage on the guide surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a self-aligning roller bearing for a planetary speed reducer that rotatably supports a planetary rotor of the planetary speed reducer.

  An automatic adjustment in which two rows of roller-shaped rollers are arranged between two rows of raceway surfaces provided on the outer diameter surface of the inner ring and a raceway surface provided on the inner diameter surface of the outer ring facing the raceway surface. In the center roller bearing, the rollers arranged in two rows are held by a cage provided with a plurality of column portions inserted between the rollers on both sides of the annular portion that is connected in an annular shape between the rows of rollers.

  There are two types of cages for this self-aligning roller bearing: one is an integral type in which the annular part and the pillars on both sides are integrated, and the other is a divided type in which the annular part is divided at the center in the axial direction. When classified by method, there are a press cage formed by pressing a metal plate such as a steel plate and a machined cage formed by cutting a metal such as steel or brass. In addition, when classified by the guide method of the cage, the roller guide type that guides the column portion with rollers, the inner ring guide type that guides the inner diameter surface of the annular portion with the outer diameter surface of the inner ring, and the annular portion It is roughly classified into an outer ring guide type that guides the outer diameter surface with the inner diameter surface of the outer ring (see, for example, Patent Document 1).

  As shown in FIG. 5, when assembling the self-aligning roller bearing, the roller 4 and the cage 5 are first assembled to the raceway surface 2a of the inner ring 2, and the inner ring 2 assembled with the roller 4 and the cage 5 is used as the outer ring. 3, the inner ring 2 inserted at a right angle is rotated by 90 ° so as to be parallel to the outer ring 3, and the inner ring 2 assembled with the rollers 4 and the cage 5 is assembled into the outer ring 3. When the inner ring 2 is inserted at a right angle, the upper and lower rollers 4 that contact the end of the raceway surface 3a of the concave outer ring 3 are removed, and after the inner ring 2 is assembled into the outer ring 3, the inner ring 2 is assembled with the inner ring 2 tilted. .

  As shown in FIG. 5, when the outer ring guide type retainer 5 is used, the outer diameter portion of the annular portion 5 a that protrudes to the outer diameter side from the column portion 5 b also hits the end of the raceway surface 3 a of the outer ring 3. The upper and lower portions of the outer diameter surface of the annular portion 5a are provided with notches 21 whose diameter A is smaller than the inner diameter B of the end of the raceway surface 3a.

  On the other hand, a planetary speed reducer is known as a speed reducer capable of obtaining a large reduction ratio, and a planetary gear speed reducer is a typical one. The planetary gear reducer revolves while rotating a plurality of planetary gears rotatably supported by carrier pins between a sun gear provided on an input shaft and an internal gear fixed to a housing or the like. The revolving motion of the planetary gear is output to the output shaft through the carrier (see, for example, Patent Document 2). There is also a planetary roller speed reducer that uses a sun gear, an internal gear, and a planetary gear as a planetary rotating body as rollers (see, for example, Patent Document 3).

  As the rolling bearing for supporting the planetary rotating body on the carrier pin, needle roller bearings are often used in small planetary reducers, and self-aligning roller bearings, tapered roller bearings, cylinders are used in medium and large planetary reducers. Roller bearings are used.

JP 2001-221237 A JP-A-7-103320 Japanese Patent Laid-Open No. 8-130853

  The spherical roller bearing for planetary reduction gears that supports the planetary rotating body of the planetary reduction gear described above on the carrier pin revolves while rotating with the planetary rotating body. In addition to the centrifugal force, centrifugal force from the center of the reducer due to revolution acts. The centrifugal force due to this revolution acts to decenter the cage from the center of the bearing, so in the roller guide type, some of the column parts are strongly abutted against the rollers, and the column parts are locally worn, There is a risk of breakage. The inner ring guide type and the outer ring guide type do not have such a fear, but the lubricant such as grease inside the bearing moves to the outer ring side by the centrifugal force due to rotation, so the inner ring type is lubricated by the guide surface. There is a problem that the drug is insufficient.

  Therefore, an outer ring guide type retainer is suitable for the cage of the spherical roller bearing for the planetary speed reducer, but the outer ring guide type retainer is incorporated in the outer ring 3 as shown in FIG. Since it is necessary to provide the notches 21 at the upper and lower portions of the outer diameter surface of the annular portion 5a serving as the guide surface, the lubricant on the guide surface is scraped off at the edge portions 21a at both ends of the notch 21, and the oil film is cut. There is a problem that becomes easier.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a self-aligning roller bearing for a planetary speed reducer that is capable of satisfactorily lubricating its guide surface without fear of damaging the pillar portion of the cage.

  In order to solve the above problems, the present invention rotatably supports a planetary rotating body of a planetary reduction gear that revolves while rotating, and has two rows of raceway surfaces provided on the outer diameter surface of the inner ring, and these Between the raceway surface and the raceway surface provided on the inner surface of the outer ring facing the raceway surface, two rows of roller-shaped rollers are arranged by being held by a cage provided with a plurality of column portions on both sides of the annular portion. In a self-aligning roller bearing for a planetary speed reducer, a configuration is adopted in which the cage is formed of a flexible resin, and the outer diameter surface of the annular portion is guided by the inner diameter surface of the outer ring. .

  That is, the cage is formed of a flexible resin, and the outer diameter surface of the annular portion is guided by the inner diameter surface of the outer ring, so that the cage assembled to the inner ring is flattened in the radial direction. So that it can be inserted at a right angle so that it does not hit the end of the raceway surface of the concave outer ring without retaining the upper and lower parts of the outer diameter surface of the annular part that becomes the guide surface. The column part of the vessel was not damaged and the guide surface could be well lubricated without causing oil film breakage.

  Examples of the flexible resin forming the cage include polyamide resins such as 46 nylon and 9T nylon, polyimide resins such as polyamideimide and thermoplastic polyimide, polyarylene sulfide resins such as polyphenylene sulfide, polyether ketone, poly Aromatic polyether ketone resins such as ether ether ketone, and mixtures thereof can be used. If necessary, these resins may be added to fibrous reinforcing materials such as carbon fibers and glass fibers, scale-like reinforcing materials such as mica and talc, microfiber reinforcing materials such as potassium titanate whiskers, polytetrafluoroethylene, and graphite. Also, a solid lubricant such as molybdenum disulfide, a sliding reinforcing material such as calcium phosphate and calcium sulfate, and the like can be blended.

  In the self-aligning roller bearing for the planetary speed reducer of the present invention, the cage is formed of a resin having flexibility, and the outer diameter surface of the annular portion is guided by the inner diameter surface of the outer ring. The cage attached to the inner ring is elastically deformed so as to be flat in the radial direction, and the end of the raceway surface of the concave outer ring is formed without providing a notch in the upper and lower portions of the outer diameter surface of the annular portion serving as the guide surface. Since it can be inserted at a right angle so as not to hit, the pillar portion of the cage is not damaged, and the guide surface can be well lubricated without causing oil film breakage.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, this self-aligning roller bearing 1 for a planetary speed reducer has an inner ring 2 provided with two rows of raceway surfaces 2a on the outer diameter surface, and each raceway surface 2a of the inner ring 2 on the inner diameter surface. An outer ring 3 provided with a raceway surface 3a, two rows of rollers 4 arranged between the raceway 2a, 3a of the inner ring 2 and the outer ring 3, and a cage for holding these two rows of rollers 4 5 and two ends of the inner ring 2 are provided with flanges 2b.

  The cage 5 is formed by injection-molding a 46 nylon polyamide resin having flexibility, and a plurality of pillars inserted between the rollers 4 on both sides of an annular portion 5a connected in an annular shape between the rows of rollers 4. It is an integral type provided with a portion 5 b, and the outer diameter surface of the annular portion 5 a that protrudes to the outer diameter side from the column portion 5 b is guided by the inner diameter surface of the outer ring 3.

  When the self-aligning roller bearing 1 is assembled, as shown in FIG. 2, the roller 4 and the cage 5 are first assembled to the raceway surface 2a of the inner ring 2, and the inner ring 2 in which the roller 4 and the cage 5 are assembled. Insert the outer ring 3 at a right angle. At this time, the upper and lower rollers 4 corresponding to the end of the raceway surface 3a of the concave outer ring 3 are removed, and the annular portion 5a of the cage 5 is elastically deformed so as to be flat in the radial direction, and its passing diameter A Is made smaller than the inner diameter B of the end of the raceway surface 3 a, and the annular portion 5 a is incorporated in the inner diameter surface of the outer ring 3. After that, the inner ring 2 inserted at a right angle into the outer ring 3 is rotated 90 ° so as to be parallel to the outer ring 3, and the inner ring 2 assembled with the rollers 4 and the cage 5 is assembled into the outer ring 3. The removed upper and lower rollers 4 are assembled by tilting the inner ring 2 after the inner ring 2 is assembled into the outer ring 3.

  3 and 4 show a planetary gear reducer using the self-aligning roller bearing 1 described above. In this planetary gear reducer, a plurality of planetary gears 15 are meshed between a sun gear 12 attached to an input shaft 11 and an internal gear 14 fixed to a housing 13, and pins of a carrier 17 connected to an output shaft 16. The planetary gears 15 are rotatably supported by the self-aligning roller bearings 1 at 17a, and the revolving motion of the planetary gears 15 that revolve while rotating between the sun gear 12 and the internal gear 14 is transmitted via the carrier 17. This is output to the output shaft 16.

  In the embodiment described above, the cage formed of a flexible resin is an integral type. However, the cage may be a split type that is divided at the center in the axial direction of the annular portion. .

  In the embodiment described above, the planetary speed reducer in which the self-aligning roller bearing is used is a one-stage planetary gear speed reducer. However, the planetary speed reducer may be a planetary roller speed reducer in which each gear is a roller. The planetary speed reducer may have a plurality of stages.

Longitudinal sectional view showing an embodiment of a self-aligning roller bearing for a planetary reduction gear Front view showing the procedure for assembling the spherical roller bearing of FIG. 1 is a longitudinal sectional view showing a planetary gear reducer using the self-aligning roller bearing of FIG. Sectional view along line IV-IV in FIG. Front view showing the procedure for assembling a conventional spherical roller bearing

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Self-aligning roller bearing 2 Inner ring 2a Raceway surface 2b 鍔 3 Outer ring 3a Raceway surface 4 Roller 5 Cage 5a Ring part 5b Column 11 Input shaft 12 Sun gear 13 Housing 14 Internal gear 15 Planetary gear 16 Output shaft 17 Carrier 17a pin

Claims (1)

  The planetary rotating body of the planetary speed reducer that revolves while rotating is rotatably supported, and is provided on two rows of raceway surfaces provided on the outer diameter surface of the inner ring, and on the inner diameter surface of the outer ring facing these raceway surfaces. In the self-aligning roller bearing for a planetary speed reducer, in which two rows of roller-shaped rollers are held and arranged between the raceway surfaces by a cage having a plurality of column portions on both sides of the annular portion, A self-aligning roller bearing for a planetary speed reducer, wherein the vessel is formed of a resin having flexibility, and the outer diameter surface of the annular portion is guided by the inner diameter surface of the outer ring.

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