JP5286959B2 - Cylindrical roller bearing - Google Patents

Description

  The present invention relates to a cylindrical roller bearing in which a plurality of cylindrical rollers are arranged so as to roll on a cage provided between an inner ring and an outer ring.

The cylindrical roller bearing is configured such that a plurality of cylindrical rollers can roll between a raceway surface formed at a substantially central portion of the outer peripheral surface of the inner ring and a raceway surface formed at a substantially central portion of the inner peripheral surface of the outer ring. Yes.
The cylindrical rollers are held at predetermined intervals along the circumferential direction by a cage provided between the outer ring and the inner ring. Specifically, the cage has a plurality of pockets formed by a pair of annular portions arranged opposite to each other in the axial direction and a column portion extending and connecting the pair of annular portions in the axial direction. Each cylindrical roller is held in the pocket at a predetermined interval along the circumferential direction.
As the cylindrical roller bearing, guide portions that can be slidably contacted with both axial end portions of the inner peripheral surface of the outer ring are provided on the outer peripheral side of each annular portion, and the guide portion is the inner peripheral surface of the outer ring during rotation of the bearing. A device that guides the rotation of the cage by sliding contact with is known (for example, see Patent Document 1).

JP-A-11-159535

However, the cylindrical roller bearing device is in a state in which the cylindrical roller is sandwiched between the guide portions, so that the lubricant such as grease or lubricating oil supplied on the raceway surface of the outer ring moves outward in the axial direction of the cage. This is regulated by the guide section. For this reason, there is a problem that the lubricant easily stays on the raceway surface, and the staying lubricant becomes a rolling resistance of the cylindrical roller and the bearing torque is likely to increase.
In order to prevent the lubricant from staying, it is conceivable that the outer shape of the guide portion is reduced to form a gap between the guide portion and the raceway surface, and the lubricant is allowed to escape from the gap. However, in this case, a new problem arises that the cage is likely to be eccentric due to the existence of the gap and the rotation cannot be guided well.
The present invention has been made in view of such circumstances, and can satisfactorily guide the rotation of the cage, and the bearing torque increases due to the retention of the lubricant on the raceway surface. It is an object of the present invention to provide a cylindrical roller bearing capable of preventing the above.

In order to achieve the above object, a cylindrical roller bearing of the present invention includes an inner ring having a raceway surface on an outer peripheral surface, an outer ring having a raceway surface on an inner peripheral surface, and a raceway surface of the inner ring and a raceway surface of the outer ring. In a cylindrical roller bearing comprising a plurality of cylindrical rollers arranged to be rollable and a cage for holding the cylindrical rollers at a predetermined interval along a circumferential direction, the cage is provided with a circumferential surface of the cage. A guide piece that protrudes from the surface and slides in contact with one of the inner race surface and the outer race surface to guide the rotation of the cage, and removes the excess lubricant on the raceway surface at predetermined intervals along the circumferential direction. Provided at both ends in the axial direction of the guide piece from the peripheral surface side of the cage, and tapered surfaces inclined toward the axial center of the portion in sliding contact with the raceway surface are formed. direction overall length, especially shorter than the axial length of said raceways It is set to.

  According to the cylindrical roller bearing configured as described above, since the guide piece is brought into sliding contact with the raceway surface of the inner ring or the outer ring, the rotation of the cage can be guided well. In addition, surplus lubricant on the raceway surface can be removed by the guide piece as the cage rotates. And since the said guide piece is provided for every predetermined interval along the circumferential direction of a holder | retainer, an excess lubricant can be escaped to the axial direction both ends of an outer ring | wheel or an inner ring | wheel. For this reason, it is possible to prevent the bearing torque from increasing due to the excessive lubricant remaining on the raceway surface.

In addition , even if the guide piece is biased to one side in the axial direction with respect to the raceway surface during the rotation of the cylindrical roller bearing, the region where the guide piece does not slide on the other side of the raceway surface, that is, the region where the lubricant is not removed. Therefore, the lubricant can be appropriately left on the raceway surface. For this reason, it is possible to avoid occurrence of insufficient supply of lubricant even under conditions where supply of lubricant is likely to be insufficient by removing excess lubricant over the entire axial length of the track surface, and the raceway surface. The lubricant remaining on at least one side in the axial direction of the roller spreads on the raceway surface due to surface tension, etc., so that an appropriate amount of lubricant is supplied to the rolling surface of the raceway surface on which the cylindrical roller rolls. can do.

  Moreover, it is preferable that the axial direction full length of the part which slidably contacts with the said track surface of the said guide piece is shorter than the axial direction full length of the said cylindrical roller. In this case, a region where the lubricant is not removed always exists on at least one side in the axial direction of the rolling surface of the raceway surface on which the cylindrical roller rolls during rotation of the cylindrical roller bearing. The lubricant can be left moderately on the running surface. For this reason, it is possible to avoid the occurrence of insufficient supply of lubricant even under conditions where supply of lubricant is likely to be insufficient by removing excess lubricant over the entire axial length of the rolling surface, An appropriate amount of lubricant can be supplied to the rolling surface by the cylindrical roller extending the lubricant remaining on at least one side in the axial direction of the rolling surface by rolling.

Further, it is preferable that the guide piece is in line contact with the raceway surface. In this case, since the sliding contact resistance of the guide piece can be reduced, the bearing torque can be reduced as compared with the conventional cylindrical roller bearing in which the guide portion of the cage is in surface contact.
Moreover, it is preferable to have the hollow which accumulate | stores the lubricant on the said track surface in the front-end | tip part of the said guide piece. In this case, since the lubricant can be temporarily stored in the recess, the lubricant in the recess can be supplied even under conditions where the supply of the lubricant is likely to be insufficient, and the supply of lubricant is insufficient. Can be prevented.

  According to the cylindrical roller bearing of the present invention, it is possible to prevent the bearing torque from increasing due to the excess lubricant remaining on the raceway surface while guiding the rotation of the cage satisfactorily by the guide piece. .

Next, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a sectional view showing a cylindrical roller bearing of an inner ring flange type according to the first embodiment of the present invention.
In FIG. 1, a cylindrical roller bearing 1 includes an inner ring 2 fixed to a rotating shaft (not shown), an outer ring 3 fixed to a housing (not shown), and a plurality of rollers arranged between the inner ring 2 and the outer ring 3 so as to be able to roll. Cylindrical rollers 4 and cages 5 for holding the cylindrical rollers 4 at equal intervals along the circumferential direction.

The inner ring 2 forms a raceway surface 2a on which the cylindrical roller 4 rolls at the axially central portion of the outer peripheral surface, and flanges 2b projecting to the outer ring 3 side are formed on both sides of the raceway surface 2a in the axial direction. It is integrally formed.
The outer ring 3 forms a raceway surface 3a on which the cylindrical roller 4 rolls in the axial center portion of the inner peripheral surface, and tapered surfaces that gradually increase in diameter toward the outside in the axial direction at both end portions in the axial direction of the raceway surface 3a. 3b is formed.
Grease G as a lubricant is applied to each raceway surface 2a, 3a over the entire circumference.

  FIG. 2 is a perspective view showing a part of the cage 5. The retainer 5 includes a pair of annular portions 5a and 5a that are spaced apart in the axial direction, and a plurality of annular portions 5a and 5a that are disposed at equal intervals along the circumferential direction of the annular portion. Each cylindrical roller 4 is disposed in a pocket 5c that is surrounded by the adjacent column portion 5b and a pair of annular portions 5a. The rollers 4 are held at predetermined intervals along the circumferential direction.

The guide piece 6 is formed on the outer peripheral surface of all the pillar portions 5b so as to protrude toward the raceway surface 3a side of the outer ring 3, and has a sliding contact portion 6a in sliding contact with the raceway surface 3a.
The guide piece 6 has a triangular cross section in which a first tapered surface 6b is formed on a pair of side surfaces extending in the axial direction, and is inclined from the column portion 5b side toward the substantially central portion in the circumferential direction of the sliding contact portion 6a. The axial length of the sliding contact portion 6a is sharp (see FIG. 3).

  With the above configuration, since the sliding contact portion 6a of the guide piece 6 is in sliding contact with the raceway surface 3a during the rotation of the cylindrical roller bearing 1, the rotation of the cage 5 can be well guided. Further, as the cage 5 rotates in the direction of arrow X in FIG. 3 with respect to the raceway surface 3a, the excess grease Gb (shaded portion in FIG. 3) of the grease G on the raceway surface 3a is slidably contacted. 6a can be scraped off and removed, and excess grease Gb can be released to both ends of the outer ring 3 in the axial direction. For this reason, it is possible to prevent the excess grease Gb from staying on the raceway surface 3a while leaving an appropriate amount of grease Ga (non-hatched portion in FIG. 3) to be thin and uniform on the entire raceway surface 3a. Therefore, it is possible to prevent the bearing torque from increasing due to the excess lubricant Gb remaining on the raceway surface 3a. In addition, since the sliding contact portion 6a is sharply formed by the pair of first tapered surfaces 6b, the entire axial length of the sliding contact portion 6a is in line contact with the raceway surface 3a, and the sliding contact resistance of the sliding contact portion 6a. Can be reduced. For this reason, a bearing torque can be reduced compared with the conventional cylindrical roller bearing with which the guide part of a retainer contacts a surface.

Further, as shown in FIG. 1, the axial total length L1 of the base end portion of the guide piece 6 is formed to be the same length as the axial total length L3 of the raceway surface 3a of the outer ring 3, and both axial end portions of the guide piece 6 In addition, a second tapered surface 6c that is inclined from the column part 5b side toward the substantially axial center of the sliding contact portion 6a is formed, and the axial length L2 of the sliding contact portion 6a that is the distal end portion of the guide piece 6 is tracked. The axial length L3 of the surface 3a and the axial length L3 of the cylindrical roller 4 equal to or smaller than the axial length L3 of the raceway surface 3a (same as the axial length L3 of the raceway surface 3a in this embodiment) are shorter.
Thereby, even if the sliding contact portion 6a is biased to one side of the raceway surface 3a in the axial direction during the rotation of the cylindrical roller bearing 1, the sliding contact portion 6a does not slide on the other side of the raceway surface 3a. Since there is always a region (L3-L2, L4-L2), that is, a region where the grease G is not removed, an appropriate amount of grease Ga can be left on the raceway surface 3a. By removing the excess lubricant Gb, it is possible to avoid insufficient supply of the appropriate amount of grease Ga even under conditions where supply of the appropriate amount of grease Ga is likely to be insufficient.

FIG. 4 is a cross-sectional view of a substantially central portion in the axial direction of the guide piece 6 in the cylindrical roller bearing 1 according to the second embodiment, and corresponds to FIG. 3 in the first embodiment. In FIG. 4, the second embodiment is different from the first embodiment in that the sliding contact portion 6a of the guide piece 6 is a flat surface, and the sliding contact portion 6a is provided with a recess 6d for temporarily storing the grease G. It is a point.
According to the present embodiment, the grease G stored in the recess 6d can be supplied to the raceway surface 3a even under a condition in which supply of an appropriate amount of grease Ga is likely to be insufficient during rotation of the cylindrical roller bearing 1. Insufficient supply of grease Ga can be prevented.

  FIG. 5 is a cross-sectional view showing a cylindrical roller bearing 21 of a type with an outer ring collar according to the third embodiment. The third embodiment is different from the first embodiment in that the outer ring 23 is provided with a flange, the inner ring 22 is not provided with a flange, and the guide piece 26 of the cage 25 is formed on the raceway surface 22a side of the inner ring 22. This is the point. In FIG. 5, the inner ring 22 forms a raceway surface 22a on which the cylindrical roller 24 rolls at the axially central portion of the outer peripheral surface, and gradually increases in diameter toward the inside in the axial direction at both axial ends of the raceway surface 22a. A tapered surface 22b is formed. The outer ring 23 is formed with a raceway surface 23a on which the cylindrical roller 24 rolls at an axially central portion of the outer peripheral surface, and flanges 23b protruding toward the inner ring 22 side are integrally formed at both axial ends of the raceway surface 23a. Yes.

The guide piece 26 protrudes from the inner peripheral surface of each column portion 25b to the raceway surface 22a side of the inner ring 22, and has a sliding contact portion 26a in sliding contact with the raceway surface 22a of the inner ring 22. The sliding contact portion 26a is in sliding contact with the raceway surface 22a during the rotation of the cylindrical roller bearing 21, so that the rotation of the cage 25 can be well guided.
Further, in the third embodiment, excess grease (not shown) on the raceway surface 22a is scraped and removed by the sliding contact portion 26a along with the relative rotation between the cage 25 and the raceway surface 22a. In addition, excess grease can be released to both axial ends of the inner ring 22. For this reason, an appropriate amount of grease (not shown) can be left thinly and uniformly on the entire raceway surface 22a, and excess grease can be prevented from staying on the raceway surface 22a. Therefore, it is possible to prevent the bearing torque from increasing due to the excess lubricant remaining on the raceway surface.

  The present invention is not limited to the above-described embodiments. For example, in each of the above-described embodiments, the guide pieces 6 and 26 are slidably contacted with the raceway surface of the raceway on the heel side. It is also possible to make sliding contact with the raceway surface of the raceway. In the above-described embodiments, the sliding contact portions 6a and 26a of the guide pieces 6 and 26 are in line contact with the raceway surface, but surface contact is also possible.

Furthermore, the above-described embodiments is formed a draft in pieces 6, 26 to all the pillar portions 5b, 25b of the cage 5, 25, but can also be formed only on a part of the column portions 5b, 25b It is. In short, the guide pieces 6 and 26 may be formed at predetermined intervals in the circumferential direction of the cages 5 and 25, preferably at equal intervals .

It is sectional drawing which shows the cylindrical roller bearing which concerns on the 1st Embodiment of this invention. It is a principal part perspective view which shows a holder | retainer. It is sectional drawing of the circumferential direction of guide piece vicinity. FIG. 6 is a circumferential sectional view of the vicinity of a guide piece in a cylindrical roller bearing according to a second embodiment of the present invention. It is sectional drawing of the cylindrical roller bearing which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

1,21 Cylindrical roller bearing 2,22 Inner ring 3,23 Outer ring 3a, 22a Raceway surface 4,24 Cylindrical roller 5,25 Cage 6,26 Guide piece 6d Depression Gb Excess grease (excess lubricant)

Claims (4)

An inner ring having a raceway surface on the outer peripheral surface;
An outer ring having a raceway surface on the inner peripheral surface;
A plurality of cylindrical rollers arranged to roll between the raceway surface of the inner ring and the raceway surface of the outer ring;
In a cylindrical roller bearing provided with a cage that holds the cylindrical roller at a predetermined interval along the circumferential direction,
A guide that protrudes from the circumferential surface of the cage to the cage and slides against one of the raceways of the inner ring and the outer ring to guide the rotation of the cage and to remove excess lubricant on the raceway surface. A piece is provided at predetermined intervals along the circumferential direction ,
Tapered surfaces are formed at both axial ends of the guide piece from the peripheral surface side of the cage toward the axial center of the portion that is in sliding contact with the raceway surface, and the axial total length of the sliding contact portion is A cylindrical roller bearing characterized by being shorter than the total axial length of the raceway surface . 2. The cylindrical roller bearing according to claim 1, wherein an axial total length of a portion in sliding contact with the raceway surface of the guide piece is shorter than an axial total length of the cylindrical roller. The cylindrical roller bearing according to claim 1, wherein the guide piece is in line contact with the raceway surface . The cylindrical roller bearing according to any one of claims 1 to 3 , further comprising a recess for storing a lubricant on the raceway surface at a tip portion of the guide piece .

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