JP2008196544A - Conical roller bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conical roller bearing which can sufficiently keep a strength of inner ring collar receiving a large end face of conical roller, moreover, reduce bearing weight. <P>SOLUTION: The conical roller bearing, which comprises an inner ring 21, an outer ring 22, a plurality of conical rollers 23 arranged to be rotatable between the inner ring 21 and outer ring 22, and a retainer 24 holding the conical rollers 23 at a predetermined space in circumference, is characterized in that a collar 26 projected outer diametral side is arranged in the large-diameter side of the inner ring 21, and a truck surface 25 reaching small-diameter end from this collar 26 is formed, and in that the outer ring 22, the conical roller 23, and the retainer 24 are assembled by engaging an engaging portion 36 projected outer diametral at the small-diameter side of the retainer 24 to the outer ring 22. <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 against a radial 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 is applied, the tapered roller 5 is pressed to the large end side, so that a flange 7 that protrudes toward the outer diameter side is provided on the large diameter side of the inner ring 2 to receive this load. It has been. 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, the engine room has been reduced, the engine output has been increased, and the transmission has been increased in stages to improve fuel efficiency. Therefore, it is desired to reduce the weight of the bearing for reducing the torque for improving the fuel efficiency.

  By the way, the flange portion 7 on the large diameter side of the inner ring 2 is necessary for receiving the axial load through the tapered roller 5 and for guiding the tapered roller 5 to rotate. On the other hand, the flange portion 8 on the small diameter side of the inner ring 2 does not play a special role during the rotation of the bearing. 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, in what provided the collar part 7 in the large diameter side of the inner ring | wheel 2, the effective weight reduction was not attained.

In view of this, conventionally, there is an inner ring in which a small-diameter side flange (small ridge) is omitted (Patent Document 1). That is, by omitting the collar portion (small collar), the size and weight are reduced.
JP 2002-54638 A

  If the small-diameter side collar portion is omitted from the inner ring as described in Patent Document 1, the tapered roller 5 falls off to the small end side before being incorporated 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.

  However, when forming the hook portion, it is necessary to form a notch portion with which the hook portion engages on the flange portion 7 side on the large diameter side of the inner ring 2. Thus, if a notch part is provided in the collar part 7, the intensity | strength of the collar part 7 will fall. Since the flange 7 receives the large end face of the tapered roller, if the strength of the flange 7 is reduced, the tapered roller cannot be received stably, and the quality of the bearing is inferior.

  In view of the above problems, the present invention provides a tapered roller bearing that can sufficiently secure the strength of the inner ring collar portion that receives the large end face of the tapered roller and can reduce the bearing weight.

  A tapered roller bearing according to 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. In the tapered roller bearing, a flange portion is provided on the large diameter side of the inner ring that protrudes toward the outer diameter side to receive the large end surface of the tapered roller, and a raceway surface that reaches the small diameter end from the flange portion is formed. The outer ring, the tapered roller, and the cage are assembled by engaging an engaging portion protruding in the outer diameter direction on the side with the outer ring.

  According to the tapered roller bearing of the present invention, the raceway surface of the inner ring reaches the small-diameter end from the flange part, and the small-diameter side flange part and the slack part of the inner ring that existed in the prior art are also omitted. Moreover, since the engaging part which engages with an outer ring | wheel is provided in the holder | retainer and the outer ring | wheel, the tapered roller, and the holder | retainer were assembled | attached by this, the fall-off | omission of the tapered roller from the outer ring | wheel can be prevented.

  A notch portion is provided on the end surface of the outer ring on the roller small end surface side, and the engagement portion is engaged with the notch portion so that the tapered roller can be prevented from coming off from the outer ring toward the opposite notch portion side. preferable.

  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, since the engaging portion of the cage is engaged with the outer ring, it is possible to prevent the cage from falling off. For this reason, it is possible to provide a bearing that can be reduced in weight to reduce torque for improving fuel efficiency. Furthermore, since it is not necessary to provide a notch portion that engages the engaging portion of the cage on the inner ring side, the strength of the flange portion that receives the tapered roller can be sufficiently ensured, and a highly accurate bearing can be configured. it can.

  The raceway surface is enlarged only in the omitted small-diameter side flange portion and the fillet portion, 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. Further, since the engaging portion of the cage is engaged with the outer ring, the outer ring, the tapered roller and the cage can be handled as an assembly (assembly unit body), and the assemblability of the entire bearing can be improved.

  By providing a notch on the end face of the outer ring on the roller small end face side and engaging the engaging part with this notch, the assembled state of the outer ring, the tapered roller and the cage can be stably maintained.

  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. Further, only a corner portion 27 is formed at a corner portion between the raceway surface 25 and the flange portion 26. The flange portion 26 in this case is a large flange that receives the axial load through the tapered roller 23 and guides the tapered roller 23 to rotate. Further, 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.

  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 23 a of the tapered roller 23 contacts (contacts) the raceway surface 25, and the large end surface 23 b of the tapered roller 23 is 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 tapered roller 23 so as to contact (contact) the inner surface 26 a of the portion 26.

  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. .

  Since the inner ring 21 configured in this manner does not have a flange on the small diameter side, the small end surface 23c of the tapered roller 23 is extended until it reaches the small diameter side end surface 21b of the inner ring 21, as shown in FIG. Can do.

  As shown in FIGS. 1 and 2, the retainer 24 includes a pair of annular portions 24 a and 24 b and a pillar portion 24 c that connects the annular portions 24 a and 24 b. And the tapered roller 23 is rotatably accommodated in the pocket 24d partitioned by the column part 24c adjacent along the circumferential direction. In the example shown in the figure, the column parts 24c extend slightly inclined with respect to the roller center O direction at equal circumferential positions.

  The small-diameter-side annular portion 24 b includes a large-diameter short cylindrical portion 35 and an engaging portion 36 that protrudes from the small-diameter end edge of the short cylindrical portion 35 in the outer diameter direction. The engaging portion 36 includes projecting pieces 36a disposed at a predetermined pitch along the circumferential direction, and engages with the outer ring 22 as shown in FIG. That is, a notch portion 37 is provided on one end surface 22 a of the outer ring 22 (end surface on the small end surface 23 c side of the tapered roller 23), and the engaging portion 36 is engaged (fitted) with the notch portion 37. At this time, the outer surface 36c of the engaging portion 36 and the end surface 22a of the outer ring are disposed on the same plane. That is, the engaging portion 36 is prevented from projecting outward in the axial direction from the end surface 22 a of the outer ring 22. As shown in FIG. 2B, the engaging portion 36 may be constituted by a disk-like body 36b that protrudes from the small diameter end edge portion of the short cylindrical portion 35 in the outer diameter direction.

  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 roller 23 is accommodated in each pocket 24 d of the cage 24. Thereafter, the outer ring 22 is fitted to the outer periphery of the cage 24. Further, the inner ring 21 is pushed in the axial direction. If the cage 24 is made of resin, the engaging portion 36 of the cage 24 can be engaged with the cutout portion 37 by elastic deformation, and if the cage 24 is made of steel plate, before the assembly. The engagement portion 36 is extended from the annular portion 24b on the small diameter side along the column portion 24c, and is engaged with the notch portion 37 by bending the extension portion by caulking or the like during assembly. Can do. At this time, there are slight gaps in the axial direction and the radial direction between the engaging portion 36 and the notch portion 37, whereby the cage 24 can move slightly in the axial direction and the radial direction. For this reason, the outer ring 20, the tapered roller 23 and the cage 24 can be rotated relative to each other.

  Until the tapered roller bearing is assembled in the machine, the tapered roller 23 tends to drop to the anti-engagement portion side by its own weight, and accordingly, the pressing force in the same direction also acts on the cage 24. Accordingly, since the engaging portion 36 is engaged with the notch portion 37 provided in the outer ring 22, the further displacement of the cage 24 toward the non-engaging portion side is restricted. In this case, since the tapered roller 23 is restricted from being displaced toward the anti-engagement portion by the outer diameter side 38 of the pocket 24d, it is possible to reliably prevent the tapered roller 23 from falling off the outer ring 22. Become.

  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 26, and the flange on the small-diameter side of the inner ring, which has existed in the past, is omitted. For this reason, this omission part and weight reduction can be achieved. And since the engaging part 36 of the holder | retainer 24 engages with an outer ring | wheel, the fall to the tapered roller 23 can be prevented. For this reason, it is possible to provide a bearing that can be reduced in weight to reduce torque for improving fuel efficiency. Further, since it is not necessary to provide a notch portion for engaging the engaging portion 36 of the retainer 24 on the inner ring 21 side, the strength of the flange portion that receives the tapered roller 23 can be sufficiently ensured, and a highly accurate bearing can be obtained. Can be configured.

  The raceway surface is enlarged only in the small-diameter side flange portion and the fillet portion which are omitted, whereby the axial center length of the tapered roller 23 can be increased, the load capacity can be improved, and a longer life can be achieved. . Further, since the engaging portion 36 of the retainer 24 engages with the outer ring, the outer ring 22, the tapered roller 23 and the retainer 24 can be handled as an assembly (assembly unit body), and the assemblability of the entire bearing is improved. can do.

  By providing a notch 37 on the end surface of the outer ring 22 on the roller small end face side and engaging the notch 37 with the engaging part 36, the assembled state of the outer ring 21, the tapered roller 23 and the cage 24 is stabilized. Can be maintained.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the engaging portions 36 are arranged at a predetermined pitch along the circumferential direction. In the case where the engaging piece 36a is provided, if the outer ring 22, the tapered roller 23, and the cage 24 can be assembled by engaging with the notch 37, the arrangement pitch, number, etc. thereof are set. Can be changed arbitrarily. In addition, in the above-described embodiment, the notch portion 37 with which the engaging portion 36 of the retainer 24 is engaged is open on the end surface 23a of the outer ring 22. However, the notch 37 is not opened on the end surface 22a. You may comprise by the annular groove formed. This tapered roller bearing may be used in a single row or in a double row. Further, the tapered roller bearing can be used in various parts where a tapered roller bearing can be conventionally used, in addition to being used for an automobile differential or transmission.

It is sectional drawing of the tapered roller bearing which shows embodiment of this invention. The retainer of the said tapered roller bearing is shown, (A) is a simplified expanded view, (B) is a simplified expanded view of the modification of a cage. 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 23 Tapered roller 24 Cage 36 Engagement part 37 Notch

Claims (2)

In a tapered roller bearing comprising 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,
Provided on the large-diameter side of the inner ring a flange that protrudes toward the outer-diameter side and receives the large end surface of the tapered roller, forms a raceway surface that reaches the small-diameter end from this flange, and the outer-diameter direction on the small-diameter side of the cage A tapered roller bearing comprising an outer ring, a tapered roller, and a cage assembled by engaging an engaging portion protruding to the outer ring.   A notch portion is provided on the end surface of the outer ring on the roller small end surface side, and the engagement portion is engaged with the notch portion to prevent the tapered roller from coming off from the outer ring toward the notch portion side. The tapered roller bearing according to claim 1.

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