JP2008196543A - Conical roller bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conical roller bearing enabling reduction in size and weight, and an increased rated load by extending a length in a roller axis direction. <P>SOLUTION: This conical roller bearing is provided with an inner ring 21, an outer ring 22, a plurality of conical rollers 23 rotatably arranged between the inner ring 21 and the outer ring 22, and a retainer 24 for circumferentially retaining the conical rollers 23 at a predetermined interval. A flange 26 for guiding the conical rollers 23 is arranged only on the side the large diameter portion of the outside diameter surface of the inner ring 21. An engagement part 36 projecting in an inner diameter direction is provided on the side of the large diameter portion of the retainer 24, and the engagement part 36 is engaged with the flange 26 of the inner ring 21. A roller slipping out preventing part 40 for sandwiching the adjacent conical rollers along the peripheral direction is formed on the side of the small diameter portion of the retainer 24. The outer end surface on the side of the small diameter portion of the retainer 24 is arranged on the further axially inner side of the opposing outside end surface 21b of the inner ring 21 to the flange and the opposing outside end surface 22b of the outer ring 22 to the flange. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tapered roller bearing.

  The driving force of the engine in the automobile is transmitted to the wheels via a power transmission system including any or all of a transmission, a propeller shaft, a differential, and a drive shaft.

  In this power transmission system, a tapered roller bearing having a high load capacity with respect to a radial load and an axial load and excellent in impact resistance is often used as a bearing for supporting the shaft. As shown in FIG. 3, the tapered roller bearing generally has an inner ring 2 having a conical raceway surface 1 on the outer peripheral side, an outer ring 4 having a conical raceway surface 3 on the inner peripheral side, and an inner ring 2. And a plurality of tapered rollers 5 disposed between the outer ring 4 and the outer ring 4, and a retainer 6 that holds the tapered rollers 5 at a predetermined circumferential interval.

  As shown in FIG. 4, the retainer 6 includes a pair of annular portions 6a and 6b and a column portion 6c that connects the annular portions 6a and 6b, and is formed between adjacent column portions 6c along the circumferential direction. The tapered roller 5 is accommodated in the pocket 6d.

  In this tapered roller bearing, the tapered roller 5 and the raceway surfaces 1 and 3 of the inner and outer rings 2 and 4 are in line contact, and the inner and outer ring raceway surfaces 1 and 3 and the roller center O are at one point on the axis P (see FIG. (Not shown).

  For this reason, when a load acts, the tapered roller 5 is pressed to the large end side. In order to receive this load, a flange portion 7 that protrudes toward the outer diameter side is provided on the larger diameter side of the inner ring 2. In addition, a flange 8 that protrudes also to the small end side of the inner ring 2 is provided so that the tapered roller 5 does not fall off to the small end side before the bearing is assembled in a machine or the like.

  In recent years, with the expansion of the interior space of vehicles, the engine room has been reduced, the engine output has been increased, and the transmission has been increased in stages to improve fuel efficiency. It is coming. In order to satisfy the life of the bearing in the usage environment, it was necessary to extend the life of the bearing.

  Against the above background, it can be proposed to increase the load capacity with the same dimensions and increase the life of the bearing by increasing the number of rollers or increasing the roller length. However, in the current structure, as described above, the inner ring 2 is provided with the flange portion (small rod) 8 on the small diameter side of the raceway surface for the reasons of bearing assembly. For this reason, there is a restriction by the flange portion 8 for increasing the length of the tapered roller 5. Each tapered roller 5 is supported by the cage 6 as described above, and the column portion 6c of the cage 6 is interposed between adjacent tapered rollers 5 along the circumferential direction. For this reason, there is a restriction by the column portion 6c even for the roller whose number of rollers is increased. Thus, there has been a limit in increasing the load capacity in the prior art.

  The raceway surface 1 is ground by a grinding body (grinding stone). For this reason, the corner portions of the raceway surface 1 and the flange portions 7 and 8 need to be provided with relief portions 16 and 17 in order to escape the peripheral portion of the grinding body (grinding stone) and avoid interference with the tapered rollers 5. was there.

  By the way, conventionally, there is an inner ring in which a small-diameter side collar (small collar) is omitted (Patent Document 1). If the collar portion on the small diameter side in the inner ring is omitted, the length of the tapered roller in the axial direction can be increased by that amount, and the load capacity can be increased. However, if the collar portion on the small diameter side is omitted in the inner ring, the tapered roller 5 falls off to the small end side before being assembled into a machine or the like. Therefore, in the device described in Patent Document 1, the cage is provided with a hook portion that engages with the large-diameter flange so that the tapered roller does not fall.

In addition, there is a retainer provided on the small diameter side of the cage to prevent the tapered roller from falling to the inner diameter side (Patent Document 2). In the thing of this patent document 2, the inner ring | wheel, the tapered roller, and the holder | retainer are made into the non-separated assembly by the hook part engaged with the large diameter side collar part, and this retaining part.
Japanese Utility Model Publication No. 58-165324 JP 2005-98412 A

  However, in the thing of patent document 1 and patent document 2, when the small end surface of a tapered roller is match | combined with the small diameter side edge of the raceway surface of an inner ring | wheel, the small end surface of a tapered roller is set to the small diameter end edge of the raceway surface of an outer ring | wheel. The smaller diameter side of the cage protrudes outward from the end faces of the inner and outer rings, and if the cage is not projected, the smaller end face of the tapered roller is attached to the smaller diameter side edge of the raceway surface of the outer ring. I can not match. That is, the axial length of the entire bearing is increased, and it has not been possible to reduce the size.

  For this reason, when the cage cannot be protruded from the inner ring or the outer ring due to the bearing peripheral structure, the load described in Patent Document 1 or Patent Document 2 is intended to increase the rated load by roller extension. I can't. In addition, if the double row is made to abut the small diameter side of the cage, the small diameter sides of the cage interfere with each other, and the assemblability and the rated load cannot be increased.

  In view of the above problems, the present invention provides a tapered roller bearing that can be reduced in size and weight, and can be extended in the axial direction of the roller, thereby increasing the rated load. To do.

  The tapered roller bearing of the present invention includes an inner ring, an outer ring, a plurality of tapered rollers arranged to roll between the inner ring and the outer ring, and a cage that holds the tapered rollers at a predetermined circumferential interval. A tapered roller bearing provided with a flange portion that guides the tapered roller only on the large diameter side of the outer diameter surface of the inner ring, and an engagement portion protruding in the inner diameter direction is provided on the large diameter side of the cage. The engaging portion is engaged with the flange portion of the inner ring, and a roller retaining portion is formed on the small diameter side of the retainer so as to sandwich adjacent tapered rollers along the circumferential direction, and the small diameter side outer end surface of the retainer is formed. The inner ring is disposed on the inner side in the axial direction with respect to the outer end surface of the inner ring and the outer end surface of the outer ring.

  According to the tapered roller bearing of the present invention, the inner ring raceway surface reaches the small-diameter end from the flange portion, and the conventionally existing small-diameter side flange portion and slimming portion of the inner ring are omitted. . For this reason, the raceway surface can be made large only in this omitted collar portion and fillet portion. Moreover, since the engaging part which engages with the collar part of the inner ring is provided in the cage, it is possible to prevent the tapered roller from falling off to the small end side. Further, since the adjacent tapered rollers are sandwiched along the circumferential direction at the roller retaining portion, it is possible to prevent the tapered rollers from falling to the inner diameter side. In addition, since the outer end surface on the small diameter side of the retaining portion is arranged on the inner side in the axial direction from the outer end surface of the inner ring and the outer surface of the outer ring, the outer end surface of the inner ring of the retaining portion is secured. And the protrusion from the outer-end surface of the outer ring of the outer ring disappears.

  The cage includes a cage main body portion including a large-diameter-side annular portion, a small-diameter-side annular portion, and a pillar portion connecting the large-diameter-side annular portion and the small-diameter-side annular portion, and the retaining portion is The small-diameter side annular portion is formed by an extending portion extending inward in the axial direction from the inner-diameter end portion of the small-diameter side annular portion made of a flat ring piece extending in the radial direction. It is set to be smaller than the wall thickness. For this reason, the retaining portion can be made compact and the tapered roller can be received stably.

  It is preferable to arrange the outer end surface of the inner ring of the inner ring and the outer end surface of the outer ring of the outer ring on the same plane. By arranging in this way, it is possible to improve the assembling property of the bearing to the other member.

  In the tapered roller bearing of the present invention, the flange portion on the small diameter side of the inner ring, which has existed in the prior art, is omitted. For this reason, this omission part and weight reduction can be achieved. In addition, the raceway surface is enlarged only in the small diameter side flange portion and the omitted portion which are omitted, whereby the axial center length of the tapered roller can be increased, the load capacity can be improved, and a longer life can be achieved. it can.

  The locking part and the roller retaining part can stably prevent the roller from separating from the inner ring. As a result, the assemblability can be improved. Moreover, the protrusion from the outer end surface of the inner ring of the inner ring and the outer end surface of the outer ring of the outer ring is eliminated. For this reason, even if the axial length of the tapered roller is increased, the cages are in contact (interference) when forming a double-row tapered roller with the back side of this bearing facing directly (with the smaller inner diameter of the inner ring). However, the rated load can be increased by extending this time.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 shows a tapered roller bearing according to the present invention. The tapered roller bearing includes an inner ring 21, an outer ring 22, a plurality of tapered rollers 23 disposed between the inner ring 21 and the outer ring 22 so as to be freely rollable, And a retainer 24 that holds the tapered rollers 23 at predetermined circumferential intervals.

  The inner ring 21 has a conical raceway surface 25 on its outer diameter surface, and a flange portion 26 is formed on the larger diameter side of the raceway surface 25 so as to protrude toward the outer diameter side. That is, the raceway surface 25 is formed from the flange portion 26 to the small diameter end, and does not have the flange portion on the small diameter side like the inner ring of the conventional tapered roller bearing. A corner portion 27 between the raceway surface 25 and the flange portion 26 is formed with a thin portion 27.

  Further, the inner surface (that is, the end surface on the small diameter side) 26 a of the flange portion 26 is inclined by a predetermined angle with respect to a plane orthogonal to the bearing axis P. That is, as shown in FIG. 1, when fitted to the raceway surface 25 of the inner ring 21, the peripheral wall 23a of the roller 23 contacts (contacts) the raceway surface 25, and the large end surface 23b of the tapered roller 23 has a flange portion. The angle formed by the raceway surface 25 and the inner surface 26 a of the flange portion 26 is adjusted to the angle formed by the peripheral wall 23 a of the roller 23 so as to contact (abut) the inner surface 26 a of the roller 26.

  For this reason, the collar portion 26 is a large collar that receives the axial load through the tapered roller 23 and rotates and guides the tapered roller 23. In addition, the conventionally provided gavel does not play a special role during the rotation of the bearing, and such a thing is omitted in the present invention.

  The outer ring 22 has a tapered raceway surface 30 on its inner diameter surface, and a plurality of tapered rollers 23 held by a cage 24 roll on the raceway surface 30 and the raceway surface 25 of the inner ring 21. .

  As shown in FIGS. 1 and 2, the retainer 24 includes a pair of annular portions 24a and 24b and column portions 24c that extend in the roller center O direction at equal circumferential positions and connect the annular portions 24a and 24b. And a cage main body portion 32. And the tapered roller 23 is rotatably accommodated in the pocket 24d partitioned by the column parts 24c and 24c which adjoin along the circumferential direction.

  The large-diameter annular portion 24a includes a large-diameter short cylindrical portion 35 and an engaging portion 36 that protrudes in the outer diameter direction. The engaging portion 36 is configured by locking pieces 36 a arranged at a predetermined pitch along the circumferential direction, and engages with the outer ring 22. That is, a notch 38 is formed on the larger diameter side of the outer diameter surface 26 c of the flange portion 26 of the inner ring 21, and the engaging portion 36 is engaged with the notch 38. At this time, there is a slight gap in the axial direction and the radial direction between the engaging portion 36 and the notch portion 38, so that the cage 24 can move slightly in the axial direction and the radial direction. The engaging portion 36 is provided corresponding to the pillar portion 24c.

  Further, the outer end surface 39 of the engaging portion 36 is arranged on the same plane as the end surface 21 a on the large diameter side of the inner ring 21 or is positioned axially inward from the end surface 21 a on the large diameter side of the inner ring 21. Note that the end surface 22 a on the large end surface 23 b side of the roller 23 of the outer ring 22 is positioned axially inward from the end surface 21 a of the inner ring 21.

  The small-diameter-side annular portion 24b is formed of a flat ring body extending in the radial direction, and is provided with a retaining portion 40 including an extending portion 40a extending inward in the axial direction from the inner diameter end thereof. As shown in FIG. 2, the extending portions 40a are arranged at a predetermined pitch along the circumferential direction. That is, the extended portion 40a is provided corresponding to the column portion 24c.

  For this reason, the tapered roller 23 is sandwiched between the extending portions 40a adjacent to each other in the circumferential direction so that the tapered roller 23 does not fall to the inner diameter side. That is, the dimension W between the extending portions 40 a adjacent to each other in the circumferential direction is slightly smaller than the diameter dimension D of the tapered roller 23. In this case, the diameter D of the tapered roller 23 increases sequentially from the small end surface 23c to the large end surface 23b along the axial direction. Therefore, the dimension W between the extended portions 40a corresponds to the outer diameter of the roller 23, that is, as shown in FIG. 2, the side edge 41 of the extended portion 40a as viewed from the outer peripheral direction, 41 is set to be located in the pocket 24d.

  The wall thickness T of the small-diameter-side annular portion 24b is set smaller than the wall thickness T1 of the large-diameter-side annular portion 24a and the column portion 24c. As a result, the small-diameter side outer end surface 42 of the retainer 24 (the outer end surface of the annular portion 24b) is disposed on the inner side in the axial direction with respect to the outer side end surface 21b of the inner ring 21 and the outer side end surface 22b of the outer ring 22. Let That is, the small-diameter side outer end surface 42 is not projected outward in the axial direction from the ruminating portion outer end surface 21 b of the inner ring 21 and the ruminating portion outer end surface 22 b of the outer ring 22.

  By the way, the cage 24 may be manufactured by pressing a steel plate, or may be a molded synthetic resin material. As the steel plate, hot rolled steel such as SPHC, cold rolled steel such as SPCC, cold rolled steel such as SPB2, or a rolled steel strip for bearings can be used. The synthetic resin material is preferably made of engineering plastic. An iron plate cage has the merit that it can be used without worrying about oil resistance (material deterioration due to immersion in oil). Further, if the resin cage is made of resin, that is, made of engineering plastic, it is not necessary to perform operations such as bottom expansion and caulking in the assembly of the bearing, so that it is easy to ensure the required dimensional accuracy. In addition, the cage made of resin is lighter than the steel plate, is self-lubricating, and has a small coefficient of friction. Therefore, combined with the effect of the lubricating oil in the bearing, It is possible to suppress the occurrence of wear due to the contact of. Further, since the resin cage is light and has a small coefficient of friction, it is suitable for reducing torque loss and cage wear at the time of starting the bearing. The engineering plastic (engineering plastic) is a synthetic resin that is mainly excellent in heat resistance and can be used in fields where strength is required. Further, a resin having increased heat resistance and strength is called a super engineering plastic, and this super engineering plastic may be used.

  Next, a method for assembling the tapered roller bearing will be described. First, the tapered rollers 23 are stored in the pockets 24 d of the cage 24. At this time, the tapered roller 23 is pushed in such that the dimension W between the extended portions 40a is expanded.

  If the cage 24 is made of a steel plate, the extended portion 40a is extended in the inner diameter direction along the annular portion 24b as shown by the phantom line in FIG. 1, and each tapered roller 23 is placed in the pocket 24d of the cage 24. Then, the extended portion 40a may be bent as indicated by the arrow A.

  Next, the inner ring 21 is fitted into the combined body of the cage 24 and the tapered roller 23. In other words, an assembly of the cage 24 and the tapered roller 23 is externally fitted to the inner ring 21. At this time, it is necessary to engage the engaging portion 36 with the notched portion 38 of the inner ring 21. In order to fit, the engaging portion 36 may be elastically deformed and fitted, but as shown by the phantom line in FIG. The inner ring 21 may be fitted into the combination of the container 24 and the tapered roller 23, and then the locking piece 36a may be bent as indicated by the arrow B.

  Thereafter, the outer ring 22 is combined with the combination of the inner ring 21, the tapered roller 23, and the cage 24 to assemble a tapered roller bearing in which the inner ring 21, the tapered roller 23, the cage 24, and the outer ring 22 are integrated. Can do.

  In the tapered roller bearing of the present invention, the raceway surface 25 of the inner ring 21 reaches the small-diameter end from the flange portion 26, and the conventional small-diameter side flange portion and thinning portion of the inner ring are omitted. is there. For this reason, this omission part and weight reduction can be achieved. Furthermore, the raceway surface is enlarged only at the omitted small diameter side flange portion and the thinning portion, whereby the axial center length of the tapered roller 23 can be increased, the load capacity can be improved, and a long life can be achieved. Can do.

  The locking part 36 and the roller retaining part 40 can stably prevent the roller from being detached from the inner ring 21. As a result, the assemblability can be improved. In addition, no protrusion of the retaining portion 40 from the outer end surface 21b of the inner ring 21 and the outer end surface 22b of the outer ring 22 is eliminated. For this reason, even if the axial center length of the tapered roller 23 is increased, the cages are in contact with each other when forming a double-row tapered roller with the back side of the bearing facing (with the smaller diameter side of the inner ring). The rated load can be increased by extending this roller without interference.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications are possible. For example, the number of locking pieces 36a constituting the engaging portion 36 is as follows. Although the increase / decrease is arbitrary, in order to stably prevent the tapered roller 23 from falling, it is preferable to arrange three or more at a constant pitch along the circumferential direction. Further, in the embodiment, the notch portion 38 is opened on the end surface 21a on the large diameter side of the inner ring 21, but without being opened on the end surface 21a, an annular shape formed on the outer diameter surface 26c of the flange portion 26. You may comprise by a ditch | groove.

  Further, the thickness T of the retaining portion 40 is such that the outer diameter end surface 42 on the small diameter side of the retaining portion 40 is axially inward of the outer end surface 21 b of the inner ring 21 and the outer end surface 22 b of the outer ring 22. It can be arbitrarily changed within the range located at. The axial protrusion amount of the retaining portion 40 and the inclination angle of the retaining portion 40 with respect to the roller axis can be arbitrarily set within a range in which the tapered roller 23 can be prevented from falling to the inner diameter side.

  This tapered roller bearing can be used for various parts where a tapered roller bearing can be used conventionally, as well as a differential and a transmission of an automobile. The tapered roller bearing may be used in a single row as shown in FIG. 1, or may be used in a double row by matching a pair with those shown in FIG.

It is sectional drawing of the tapered roller bearing which shows embodiment of this invention. It is a simple development view of the retainer of the tapered roller bearing. It is sectional drawing of the conventional tapered roller bearing. It is a simplified perspective view of the conventional tapered roller bearing retainer.

Explanation of symbols

21 Inner ring 21b Small-diameter side end face 22 Outer ring 22b Small-diameter side end face 23 Tapered roller 24 Cage 24a Annular part 24b Annular part 40a Extension part 40 Retaining part

Claims (3)

The inner ring includes an inner ring, an outer ring, a plurality of tapered rollers arranged to roll between the inner ring and the outer ring, and a retainer that holds the tapered rollers at a predetermined circumferential interval. A tapered roller bearing provided with a flange portion that guides the tapered roller only on the side,
An engaging portion that protrudes in the inner diameter direction is provided on the large diameter side of the cage, and this engaging portion is engaged with the flange portion of the inner ring, and adjacent to the small diameter side of the cage along the circumferential direction. A roller retaining portion is formed to sandwich the matching tapered rollers, and the outer diameter end surface on the small diameter side of the cage is arranged on the inner side in the axial direction from the outer end surface of the inner ring and the outer end of the outer ring. Tapered roller bearing.   The cage includes a cage main body portion including a large-diameter-side annular portion, a small-diameter-side annular portion, and a pillar portion connecting the large-diameter-side annular portion and the small-diameter-side annular portion, and the retaining portion is Consists of an extended portion extending inward in the axial direction from the inner diameter end portion of the small-diameter side annular portion formed of a flat ring piece extending in the radial direction, and the wall thickness of the small-diameter side annular portion is set to the large-diameter side annular portion and the column portion 2. The tapered roller bearing according to claim 1, wherein the tapered roller bearing is set to be smaller than the thickness of the tapered roller bearing.   The tapered roller bearing according to claim 1 or 2, wherein the outer end surface of the inner ring and the outer end surface of the outer ring are arranged on the same plane.

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