JP2006144815A - Roller bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate the slidable movement of a retainer on a member in proximity to the retainer by skew without changing outline dimensions in a roller bearing with the retainer. <P>SOLUTION: Raceway grooves 1b and 2b are formed in the raceway surfaces 1a and 2a of inner and outer rings 1 and 2 at its lateral center parts. Rollers 3 and balls 4 are assembled in one row between the inner and outer rings 1 and 2, and the assembled rollers 3 and balls 4 are held by one retainer 5. Accordingly, since its axial movement is restricted by the balls 4 even if the retainer 5 receives an axial force from the rollers 3 by skew, it is not brought into contact with a flange member 4 in contact with the retainer while the outline dimensions of the roller bearing are the same as those of general bearings. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a roller bearing with a cage.

  In general, in a roller bearing with a cage, as shown in FIG. 4, it is arranged between the raceway surfaces 51 a and 52 a of the inner and outer rings 51 and 52 due to variations in radial load distribution in the circumferential direction, variations in dimensional accuracy, and the like. The rotation speed varies among the rollers 53, and the cage 54 that receives the compression / tensile load from the rollers 53 cannot hold the rollers 53 in a stable posture. Phenomenon). In particular, the higher the rotational speed of the bearing, the greater the variation in the revolution speed between the rollers 53, and the more likely the skew occurs. When the skew occurs, the roller 53 moves in the axial direction along with the rotation, and the cage 54 is pressed against a member close to the bearing end surface (in the example of FIG. 4, the flange member A fitted on the outer periphery of the rotation shaft). The cage 54 slides with the proximity member to generate friction and heat generation, which causes a reduction in bearing life.

  For this reason, usually, in order to suppress the magnitude of the skew, a dimensional tolerance of the cage is tightened or a radial clearance in the bearing is designed to be small. However, in such a method, there is a limit in processing at the time of manufacturing the bearing, and in particular, when the cage is manufactured by injection molding of synthetic resin, it is not easy to improve the dimensional accuracy. Accordingly, it is difficult to suppress the axial movement of the roller due to skew, and there is a possibility that sliding of the cage with the proximity member may occur.

  On the other hand, a needle roller bearing (ball needle bearing) is known in which the axial movement of the cage is restricted by a ball in order to prevent the cage from sliding with the proximity member (non-ball bearing). (See Patent Document 1). As shown in FIG. 5, this bearing is provided with raceway grooves 55b and 56b on the sides of raceway surfaces 55a and 56a of inner and outer rings 55 and 56, and a plurality of balls 57 rolling on the raceway grooves 55b and 56b. Even if the needle roller 58 pushes the retainer 59 in the axial direction due to skew, the retainer 59 is restricted from moving in the axial direction by the ball 57, and is a proximity member. There is no contact with (not shown).

However, in the above needle roller bearings, it is necessary to increase the axial length so that the needle rollers and balls can be arranged in two rows, so international compatibility is one of the features of general roller bearings. And there is a problem that it is difficult to replace many existing bearings.
“Known and Conventional Techniques”, JPO, December 27, 1983, No. 19, p. 124

  An object of the present invention is to eliminate sliding with a proximity member of a cage due to skew in a roller bearing with a cage without changing the external dimensions.

  In order to solve the above-described problems, the present invention provides a roller bearing including a cage that holds a plurality of rollers arranged between raceway surfaces of inner and outer rings, and a raceway at a center portion in the width direction of the raceway surface of the inner and outer rings. A groove is provided, and a plurality of balls that roll on the raceway groove are arranged at predetermined positions in the circumferential direction between the inner and outer rings, and the cage is configured such that each roller is a rectangular pocket and each ball is a circular shape. Each was accommodated in a pocket.

  In other words, the rollers and balls are assembled in a row between the inner and outer rings so that the outer dimensions do not become larger than general bearings, and the assembled rollers and balls are held by one cage, so that the cage can be Even if the force of the direction is received, the movement in the axial direction is restricted by the ball.

  In the above configuration, if the raceway grooves of the inner and outer rings are formed so that a radial clearance is generated between the inner and outer rings and the ball is not subjected to a radial load, the holding driven by the revolution of the roller is maintained. Since the cage revolves the ball, the cage receives less load from the roller and ball than the ball subjected to radial load attempts to revolve at a slower speed than the roller, resulting in damage to the cage. There is less risk of heat generation, and less heat is generated due to sliding between the rollers and the inner and outer rings of the ball.

  When the cage is made of synthetic resin, the cage includes a cylindrical cage body having the rectangular pocket and a circular pocket, and an annular member attached to one end surface of the cage body. The rectangular pocket is opened at one side end of the cage body, a ball introduction path having a width smaller than the diameter of the ball is formed from the circular pocket to one side end of the cage body, and the rollers and By assembling the opening of one side end of the rectangular pocket and the entrance of the ball introduction path with the annular member in a state where the ball is incorporated, the assembly work of the bearing can be simplified.

  In the present invention, as described above, the rollers and balls assembled in a row between the inner and outer rings of the bearing are held by one cage, and even if the cage receives an axial force from the rollers due to skew, Since the movement in the axial direction is restricted, friction and heat generation due to sliding with the proximity member of the cage can be eliminated, and the bearing life can be extended. In addition, since the bearing to which the present invention is applied can be formed in the same outer dimensions as a general bearing, it can be easily replaced with an existing bearing.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, the roller bearing of this embodiment is provided with raceway grooves 1b and 2b at the center in the width direction of the raceway surface 1a on the outer periphery of the inner ring 1 and the raceway surface 2a on the inner periphery of the outer ring 2. The needle roller 3 and the ball 4 are assembled in a row between the inner and outer rings 1 and 2 and held by a single cage 5. The balls 4 are arranged at positions at equal intervals in the bearing circumferential direction. Further, the raceway grooves 1b and 2b of the inner and outer rings 1 and 2 are formed so that a radial gap is formed between the inner and outer rings 1 and 2 so that the ball 4 does not receive a radial load.

  As shown in FIG. 3A, the cage 5 includes a cylindrical cage body 6 having a rectangular pocket 6a for accommodating the roller 3 and a circular pocket 6b for accommodating the ball 4, and the cage body. 6 and an annular member 7 attached to one end face. Both of these members are manufactured by injection molding of synthetic resin. Further, the rectangular pocket 6a of the cage body 6 is formed so as to open at one end of the body 6, and a ball introduction path 6c having a width smaller than the diameter of the ball 4 is formed from the circular pocket 6b to one end of the body 6. Has been. Then, as shown in FIG. 3B, at the time of assembling the bearing, the roller 3 and the ball 4 are assembled, and the opening at one end of the rectangular pocket 6a and the inlet of the ball introduction path 6c are closed with the annular member 7. It has become.

  This bearing has the above-described configuration, and the ball 4 restrained in the axial direction by the raceway grooves 1b and 2b of the inner and outer rings 1 and 2 is held by the cage 5 together with the rollers 3. Even if skew occurs due to variations in revolution speed and the roller 3 pushes the cage 5 in the axial direction, the cage 5 moves only by an axial gap with the ball 4. Accordingly, if the axial gap between the ball 4 and the cage 5 is set smaller than the axial gap between the cage 5 and the flange member A fitted into the rotating shaft so as to be close to the bearing end surface, the cage 5 and Since contact with the flange member A does not occur, friction and heat generation due to sliding of both members can be eliminated, and the bearing life can be extended. In addition, since the external dimensions can be the same as that of a general bearing, it can be easily replaced with an existing bearing.

  Further, since the ball 4 is pushed and revolved by the cage 5 driven by the revolution of the roller 3 without receiving the radial load, the ball 4 receiving the radial load tries to revolve at a slower speed than the roller 3. Compared to the case, the load that the cage 5 receives from the rollers 3 and the balls 4 is small. Accordingly, the cage 5 is less likely to be damaged, and heat generated by the sliding of the roller 3 and the ball 4 with the inner and outer rings 1 and 2 is small.

  Next, the assembly procedure of this bearing will be described. First, the ball 4 is assembled between the raceway grooves 1b and 2b of the inner and outer rings 1 and 2 and set at a predetermined position in the circumferential direction. Then, by inserting the cage body 6 between the inner and outer rings 1 and 2 from one side end, each ball 4 is press-fitted into the ball introduction path 6c and accommodated in the circular pocket 6b. Next, the roller 3 is inserted into the rectangular pocket 6a from one side end of the cage body 6 and accommodated. Finally, the annular member 7 is attached to one side end face of the cage body 6 to close the opening at one side end of the rectangular pocket 6a and the entrance of the ball introduction path 6c.

  By the above-described assembly procedure, this bearing can be easily assembled with the same degree of effort as a deep groove ball bearing in which the cage is divided into two.

  The present invention is naturally applicable to a cylindrical roller bearing as well as the needle roller bearing as in the embodiment. Various designs are possible for the number of rollers and balls and their circumferential positions.

Front sectional view of the roller bearing of the embodiment Side sectional view of the bearing of FIG. a is an exploded front sectional view of the cage of FIG. 1, and b is an explanatory view of an assembly procedure of the cage of a. Front sectional view showing the state when skew occurs in a conventional bearing Front sectional view of another conventional bearing

Explanation of symbols

Reference Signs List 1 inner ring 1a raceway surface 1b raceway groove 2 outer race 2a raceway surface 2b raceway groove 3 roller 4 ball 5 cage 6 cage body 6a, 6b pocket 6c ball introduction path 7 annular member A collar member

Claims (3)

  In a roller bearing provided with a cage for holding a plurality of rollers arranged between the raceway surfaces of the inner and outer rings, a raceway groove is provided in the center in the width direction of the raceway surface of the inner and outer rings, and the raceway groove is rolled. A plurality of balls are arranged at predetermined positions in the circumferential direction between the inner and outer rings, and the cage accommodates the rollers in a rectangular pocket and the balls in a circular pocket. Roller bearing.   2. The roller bearing according to claim 1, wherein the raceway grooves of the inner and outer rings are formed so that a radial gap is formed between the inner and outer rings.   The cage is made of a synthetic resin, and includes a cylindrical cage body having the rectangular pocket and the circular pocket, and an annular member attached to one side end surface of the cage body. Opening at one side end of the cage body, forming a ball introduction path having a width smaller than the diameter of the ball from the circular pocket to one side end of the cage body, and incorporating the rollers and the ball, The roller bearing according to claim 1, wherein an opening at one side end of the rectangular pocket and an inlet of the ball introduction path are closed by the annular member.

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