JP2009168064A - Conical roller bearing and differential - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce bearing torque by adjusting an oil inflow amount into a bearing 1 and reducing oil stirring resistance inside the bearing 1 as much as possible, in the conical roller bearing 1 in which a plurality of conical rollers 4 are arranged between an inner wheel 2 and an outer wheel 3 to roll in a circumferential direction via a retainer 5. <P>SOLUTION: A small-diameter side end part of the retainer 5 is provided with an extension part 5b facing to an outer peripheral surface of a small-diameter side end part (2c) of the inner wheel 2 so as to make a clearance which is to be a non-contact sealing part. An axial-direction dimension of the extension part 5b is set to be larger than the thickness of the retainer 5. The retainer 5 is provided with a passage 6 through which lubricant circulates between the extension part 5b side and a conical roller 4 side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a tapered roller bearing and a differential lubricated with a lubricant such as oil. The tapered roller bearing is used not only for supporting a rotating shaft such as an automobile differential or a transaxle, but also for supporting a rotating shaft such as a machine tool.

  Tapered roller bearings generally hold the inner ring, outer ring, a plurality of tapered rollers interposed between the inner and outer rings, and a plurality of tapered rollers in a state where they are arranged at substantially equal intervals around the circumference. It is the structure which has a holder | retainer.

  This tapered roller bearing is widely used because it can support a large radial load and an axial load while being relatively compact, and can be used at a relatively high speed.

  When this tapered roller bearing is used in an oil-lubricated environment, a large amount of oil flows into the bearing from the small-diameter end of the inner ring and is discharged from the large-diameter side due to the pump action accompanying the rotation of the bearing, that is, the oil feed action. Become so. At that time, in addition to the rolling resistance and sliding resistance between the tapered roller and the inner ring, resistance due to agitation of the inflowing oil is added, so that the bearing torque tends to increase.

  On the other hand, in order to reduce torque, for example, in the techniques shown in Patent Documents 1 and 2, in a tapered roller bearing, the end portion on the small diameter side of the cage is bent inward in the radial direction, and this bent portion is connected to the inner ring. The small diameter side cylindrical portion and the small flange portion are opposed to each other through an appropriate gap, and the oil inflow amount between the inner and outer rings is reduced in consideration of the gap.

Further, in the technique shown in Patent Document 3, the end portion on the small diameter side of the cage is bent radially inward, the inner diameter side of the bent portion is further extended outward in the axial direction, and the extended portion is The structure is such that the oil inflow amount between the inner and outer rings is reduced by facing the outer peripheral surface of the small diameter portion of the inner ring in a non-contact manner.
JP 2005-69421 A JP 2007-138992 A JP 2007-225037 A

  In all of the conventional examples of Patent Documents 1 to 3, the bent portion of the cage is brought close to the inner ring so that the small-diameter side opening between the inner and outer rings is closed. The oil inflow is reduced.

  In such a conventional example, in order to adjust the oil inflow amount into the bearing, it is necessary to adjust the distance between the conical body portion of the cage and the outer ring.

  In the conventional examples of Patent Documents 1 and 2, the small-diameter side end of the cage is bent inward in the radial direction, and the bent portion is inserted through a suitable gap between the small-diameter cylindrical portion and the small collar portion of the inner ring. The labyrinth seal is formed so as to face each other. In these conventional examples, the non-contact facing portion of the labyrinth seal depends on the thickness of the cage, but depending on the conditions in which the bearing is used, the axial length of the non-contact facing portion is sufficient to obtain a sufficient sealing effect. It is considered that the thickness needs to be equal to or greater than the thickness of the bent portion of the cage.

  In addition, the conventional example of Patent Document 3 places importance on reducing the amount of oil flowing into the bearing, and there is no description about supplying oil to a portion that needs to be lubricated near the inner ring. Moreover, although the extension part extended in an axial direction is provided in the front-end | tip of the radially inward bending part formed in the small diameter side edge part of a holder | retainer, it does not mention especially the axial direction dimension of this extension part. There is room for improvement here.

  The present invention is a tapered roller bearing in which the amount of oil flowing into the bearing is optimized, the oil stirring resistance inside the bearing is made as small as possible, and the bearing needs to be lubricated while reducing the torque of the bearing. The purpose is to improve the oil supply to the plant. Another object of the present invention is to reduce the oil agitation resistance and reduce the torque of the differential by using the tapered roller bearing as a support bearing for a differential drive pinion shaft.

  The present invention is a tapered roller bearing in which a plurality of tapered rollers held by a substantially tapered cylindrical cage are disposed between an inner ring and an outer ring so as to be able to roll in the circumferential direction. An extension portion is provided at the end portion on the small diameter side so as to be opposed to the outer peripheral surface of the end portion on the small diameter side of the inner ring to form a non-contact sealing portion, and the axial dimension of the extension portion is determined by the cage. The retainer is provided with a passage through which the lubricant can flow inside and outside the bearing.

  According to this configuration, when oil is supplied from the small-diameter end between the radially opposed inner and outer rings, first, the facing gap between the extension of the cage and the small-diameter end of the inner ring is a so-called labyrinth seal. Since this is a non-contact sealing part, the inflow of oil from here is restricted.

  Therefore, the oil flows into the tapered roller bearing from a gap between the main body portion (for example, a conical portion) of the cage and the outer ring or a passage provided in the cage.

  Therefore, the oil flowing from between the main body of the cage and the outer ring passes along the raceway surface of the outer ring, so that the contact part between the outer ring and the tapered roller is lubricated and cooled, and then discharged. In addition, the fluid flows toward the contact portion between the large-diameter end of the inner ring and the large end surface of the tapered roller, and the contact portion is lubricated and cooled before being discharged.

  On the other hand, the oil flowing in from the cage passage circulates between the conical rollers adjacent in the circumferential direction to lubricate and cool the contact portion between the inner ring and the tapered roller. It flows toward the contact portion between the portion and the large end surface of the tapered roller, and after being lubricated and cooled, it is discharged.

  By the way, the oil that has flowed into the tapered roller bearing is sent to the discharge side by a pumping action associated with the rotation of the bearing, so that the oil flow inside the bearing as described above is not delayed by this pumping action. Yes.

  Preferably, a small flange portion for restricting the axial movement of the tapered roller is provided at the small diameter side end portion of the inner ring, and a smaller diameter than the small flange portion is provided on the axially outer side from the small flange portion. A small-diameter cylindrical portion is provided, and the extension portion of the cage is formed in a cylindrical shape so as to be opposed to and parallel to the small-diameter cylindrical portion of the inner ring.

  In this case, the small-diameter cylindrical portion of the inner ring and the extension portion of the cage are shaped along their rotational axes, and in the inner space of the facing gap between the small-diameter cylindrical portion of the inner ring and the extension portion of the cage. Since there is a wall called a small collar part, it is difficult for oil to flow in from the facing gap. In addition, the presence of the small collar portion allows the inner ring to be non-separated in a state where a plurality of tapered rollers held by the cage are assembled. Workability until assembly is improved.

  In addition, the oil flowing in from the cage passage circulates between the adjacent tapered rollers in the circumferential direction, lubricates and cools the contact portion between the inner ring and the tapered roller, and also reduces the small diameter of the inner ring and the tapered roller. It flows between the end face and between the small ring part of the inner ring and the base part of the extension part of the cage, and lubricates and cools it.

  Preferably, the passage is a hole penetrating in an axial direction in an annular wall portion that connects the main body portion of the cage and the extension portion and extends radially outward.

  In this case, since the passage is a hole along the axial direction, oil easily flows in, and management of the amount of oil flowing into the tapered roller bearing becomes relatively easy. In addition, the passage can be formed relatively easily, for example, by drilling or the like, which is advantageous in suppressing an increase in manufacturing cost.

  Preferably, the main body portion of the cage is brought close to the outer ring side, and the cage is guided by the tapered rollers so as not to contact the inner and outer rings, When the facing gap between the extension portion and the end portion on the small diameter side of the inner ring is X, and the guide gap of the cage is Y, the relationship is X> Y.

  In this case, during the rotation of the cage, the cage does not need to contact the inner and outer rings due to the rotational deflection, and the extension portion of the cage also contacts the small diameter side end portion (small diameter cylindrical portion) of the inner ring. Therefore, it is possible to reduce unnecessary friction loss.

  Further, according to the present invention, the drive pinion shaft is rotatably supported in the differential case by two rolling bearings separated in the axial direction, and the oil in the differential case is supplied from between the axial facings of the both rolling bearings. A tapered roller bearing having the above-described configuration is a differential in a lubrication configuration that is circulated and returned through the both rolling bearings, and at least the rolling bearing disposed on the drive pinion gear side of the drive pinion shaft. It is said that it is said.

  Thus, it is possible to specify differentially the usage target of the tapered roller bearing according to the present invention. In this case, since the oil agitation resistance by the support bearing of the drive pinion shaft is reduced, it is advantageous in reducing the differential torque.

  According to the present invention, it is possible to reduce the torque of the tapered roller bearing, and it is possible to supply oil to a portion requiring lubrication inside the tapered roller bearing, thereby improving the lubricity. . Further, according to the present invention, by using the tapered roller bearing as a support bearing for a differential drive pinion shaft, it is possible to reduce oil agitation resistance and to reduce the differential torque.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best embodiment of the present invention will be described in detail with reference to the drawings. 1 to 6 show an embodiment of the present invention.

  Here, prior to the description of the portion to which the features of the present invention are applied, a schematic configuration of the tapered roller bearing to which the features of the present invention are applied will be described with reference to FIGS. 1 and 2.

  A tapered roller bearing 1 shown in FIGS. 1 and 2 includes a plurality of tapered rollers 4 interposed between an inner ring 2 and an outer ring 3, and the plurality of tapered rollers 4 are spaced by a cage 5 at substantially equal intervals around the circumference. It is the structure which was hold | maintained rotatably in the state arrange | positioned. Reference numeral 7 denotes an inner diameter side member such as a rotating shaft, and 8 denotes an outer diameter side member such as a case.

  The inner ring 2 is formed of a substantially cylindrical thick member, and a conical raceway surface (reference numeral omitted) is formed in an axially intermediate region of the outer peripheral surface thereof. In the inner ring 2, a large flange portion 2a extending radially outward is provided on the large diameter side of the raceway surface, and a small flange portion 2b extending radially outward is provided on the small diameter side of the raceway surface. Is provided.

  In general, the large collar portion 2a of the inner ring 2 mainly guides the rolling operation of the tapered roller 4 in the circumferential direction when rotating the tapered roller bearing 1 in a completed state. On the other hand, the small collar portion 2b of the inner ring 2 mainly prevents the assembly of the inner ring 2, the plurality of tapered rollers 4 and the cage 5 from being separated in the state where the outer ring 3 is not attached in the process of assembling the tapered roller bearing 1. The axial movement of the tapered roller 4 is restricted.

  The outer ring 3 is made of a substantially cylindrical thick member, and a conical raceway surface (reference numeral omitted) is formed on the inner peripheral surface thereof. On the small diameter end side of the raceway surface of the outer ring, a cylindrical surface (reference numeral omitted) is provided along the axial direction.

  The cage 5 is made of a substantially conical cylindrical plate material, and is provided with pockets 5a that are accommodated so as to rotatably hold the tapered rollers 4 at several locations at substantially equal intervals around the circumference.

  Next, portions to which the features of the present invention are applied will be described in detail with reference to FIGS.

  In short, when the tapered roller bearing 1 having the above-described configuration is used in the form of oil lubrication, the oil agitation inside the bearing 1 is optimized by optimizing the amount of oil flowing into the bearing 1 so as not to be excessive or insufficient. After reducing the resistance as much as possible, a necessary and sufficient amount of oil is applied to a lubrication-required part in the bearing 1, for example, a sliding part between the large collar 2a of the inner ring 2 and the large end of the tapered roller 4. It is devised to enable supply.

  Specifically, first, a small-diameter cylindrical portion 2c extending outward in the axial direction is provided on the outer side in the axial direction of the small flange portion 2b of the inner ring 2. The small diameter cylindrical portion 2c is formed with a smaller diameter than the small flange portion 2b.

  On the other hand, on the small diameter side end portion of the cage 5, an extension portion 5 b that is opposed in parallel is provided so as to create an appropriate gap on the outer peripheral surface of the small diameter cylindrical portion 2 c of the inner ring 2.

  In the cage 5, an annular wall portion 5 c is provided between the extension portion 5 b and the main body portion (conical shape portion) of the cage 5 along the radial direction. In short, the annular wall portion 5c is a portion that connects the extension portion 5b and the main body portion (conical portion) of the cage 5.

  The cage 5 is provided with a plurality of passages 6 through which oil as a lubricant can be circulated inside and outside the bearing. As shown in FIG. 3, each passage 6 is a hole that penetrates the annular wall portion 5 c of the cage 5 in the axial direction. The opening shape of the passage 6 is, for example, a circle, but can be, for example, an ellipse, a rectangle, or the like. In addition, the opening area of the passage 6 is set to a size as required mainly in consideration of the total oil inflow amount from all the passages 6.

  Specifically, the passage 6 is installed in a region between the pockets 5 a adjacent to each other in the circumferential direction in the annular wall portion 5 c of the cage 5. However, the formation position of the passage 6 can be set in an area in the same phase as each pocket 5a, and is set in both the area in phase with each pocket 5a and the area between each pocket 5a. It is also possible. Further, the passages 6 may be installed at every other circumferential direction of the respective regions or every other two.

  The opposing gap between the small diameter cylindrical portion 2c of the inner ring 2 and the extension portion 5b of the cage 5, and the opposing gap between the root portion of the extension portion 5b and the outer surface of the small collar portion 2b of the inner ring 2 are called so-called labyrinth seals. It is a non-contact sealing part.

  In order to ensure the sealing action as the labyrinth seal, each opposing dimension of the gap serving as the non-contact sealing portion is set small, and the length dimension of the axial linear portion along the rotation axis O is long in the gap. Is set.

  Furthermore, the tapered roller bearing 1 described above is configured such that the cage 5 is guided by the tapered rollers 4, so that the cage 5 is rotated by the runout during rotation of the cage 5. The extension portion 5b of the retainer 5 is also set so as not to contact the small diameter cylindrical portion 2c of the inner ring 2, thereby reducing unnecessary friction loss. It has become.

  For reference, as shown in FIG. 4, the opposing gap between the extension 5b of the cage 5 and the small diameter cylindrical portion 2c of the inner ring 2 is X, and the guide gap of the cage 5, that is, the pocket 5a and the tapered roller 4 If the facing gap is Y, the relationship X> Y is set.

  In addition, the main body portion of the cage 5 is set so as to be close to the outer ring 3 side, but the radial facing gap Z between the outer ring 3 and the main body portion of the cage 5 is set to a relationship of Z> X. Has been. This relationship is based on the premise that the rotational axis O of the cage 5 and the rotational axes O of the inner and outer rings 2 and 3 are made to coincide with each other.

  Next, the flow of oil in the form of oil lubrication for the tapered roller bearing 1 to which the features of the present invention are applied will be described.

  For example, as shown in FIG. 5, when oil is supplied from the small-diameter end side of the radially opposed annular spaces of the inner and outer rings 2, 3, first, the extension 5 b of the cage 5 and the small-diameter cylindrical part 2 c of the inner ring 2. The gap between the two is a non-contact sealing portion such as a so-called labyrinth seal, so that the oil inflow from here is greatly limited.

  Therefore, the oil flows into the tapered roller bearing 1 from the gap between the main body portion of the cage 5 and the outer ring 3 as indicated by a two-dot chain line arrow in FIG. As shown, it flows into the tapered roller bearing 1 from the passage 6 provided in the cage 5.

  First, oil flowing from between the main body portion of the cage 5 and the outer ring 3 passes mainly along the raceway surface of the outer ring 3 as indicated by a two-dot chain arrow in FIG. In addition to being lubricated and cooled after the contact portion between the tapered roller 4 and the tapered roller 4 is discharged, it enters the pocket 5a and contacts the inner wall of the pocket 5a with the tapered roller 4, or the large collar portion 2a of the inner ring 2 and the tapered portion. By flowing toward the contact portion with the large end surface of the roller 4, these contact portions are lubricated and cooled before being discharged.

  On the other hand, the oil flowing in from the passage 6 of the cage 5 flows between the tapered rollers 4 adjacent to each other in the circumferential direction as shown by broken line arrows in FIG. 5, and the contact portion between the inner ring 2 and the tapered rollers 4. In addition to lubricating and cooling the inner ring 2, it flows between the small flange portion 2 b of the inner ring 2 and the small end surface of the tapered roller 4, or between the small flange portion 2 b of the inner ring 2 and the root portion of the extension portion 5 b of the cage 5. Then, it is lubricated and cooled, and flows toward the contact portion between the large collar portion 2a of the inner ring 2 and the large end surface of the tapered roller 4 described above, lubricated and cooled, and then discharged. .

  Although the small end surface of the tapered roller 4 and the base portion of the extension portion 5b of the cage 5 are basically designed to be non-contact with the small flange portion 2b of the inner ring 2, an excessive amount is required during the rotation operation. Since there is a possibility of contact when a radial load or an axial load is applied, it is advantageous in reducing heat generation and wear due to contact at that time.

  By the way, the oil that has flowed into the tapered roller bearing 1 is sent to the discharge side by a pumping action associated with the rotation of the bearing 1, so that the oil flow inside the bearing 1 as described above is not delayed by this pumping action. It has become.

  As described above, in the tapered roller bearing 1 to which the feature of the present invention is applied, the non-contact sealing portion formed of a minute gap is provided between the small-diameter cylindrical portion 2c of the inner ring 2 and the extension portion 5b of the cage 5 in the radial direction. After making it and making it the form which block | closes the radial direction opposing of the inner ring | wheel 2 and the holder | retainer 5, it is the oil of the radial direction opposing clearance gap between the outer ring | wheel 3 and the main body part of the holder | retainer 5, and the channel | path 6 of the holder | retainer 5. It is configured to allow inflow.

  By adopting such a configuration, the total oil inflow amount into the tapered roller bearing 1 can be properly managed without excess or deficiency, so that the oil agitation resistance can be made as small as possible. Thus, the torque of the tapered roller bearing 1 can be reduced. In addition, between the small flange portion 2b of the inner ring 2 and the small end surface of the tapered roller 4, between the small flange portion 2b of the inner ring 2 and the extended portion 5b root portion of the cage 5, and the large flange portion 2a of the inner ring 2 Since a necessary and sufficient amount of oil can be supplied to the large end surface of the tapered roller 4, it is possible to satisfactorily ensure lubricity at a location where lubrication may be insufficient.

  In particular, the sealing action by the non-contact sealing portion formed between the small-diameter cylindrical portion 2c of the inner ring 2 and the extension portion 5b of the cage 5 is comprehensively managed by the axial length and the radial facing gap. Because it only needs to be designed, it is easier to implement and practical than the design for obtaining a sufficient sealing action with a non-contact sealing part with a relatively short axial length as in the conventional example. It can be said that.

  By the way, an example of the usage object of the above-mentioned tapered roller bearing 1 will be described with reference to FIG. FIG. 6 shows a differential mounted on an automobile or the like.

  The differential 50 shown in the figure is an example of a type mounted on a front engine / rear drive (FR) type vehicle.

  In the figure, 51 is a differential case (also called a differential carrier), 52 is a differential transmission mechanism, 53 is a drive pinion shaft, and 54 is a drive pinion gear.

  The differential case 51 has, for example, a two-piece structure in which a front case 51a and a rear case 51b are combined. A predetermined amount of lubricating oil is stored in the differential case 51.

  The differential transmission mechanism 52 distributes the power input from the drive pinion shaft 53 to the left and right axles (referred to as drive shafts) as necessary and outputs driving force to wheels (not shown). The case 51 is disposed on the front case 51a side.

  Although this differential transmission mechanism 52 is a generally known configuration, it is a portion that is not directly involved in the features of the present invention. Therefore, in FIG. 6, only the ring gear 52a is shown, and other components ( Detailed illustrations and explanations of pinion gears and side gears are omitted.

  The drive pinion shaft 53 is rotatably supported at a required position of the front case 51a of the differential case 51 via rolling bearings 55 and 56 at two locations separated in the axial direction.

  The drive pinion shaft 53 is in a horizontal posture, and a drive pinion gear 54 is integrally formed on the inner end side thereof. The drive pinion gear 54 is meshed with the ring gear 52 a of the differential transmission mechanism 52.

  A flange joint 57 to which a propulsion shaft (not shown) (not shown) is coupled is attached to the outer end side of the drive pinion shaft 53. That is, the drive pinion shaft 53 is an input shaft for driving force.

  One or both of the two rolling bearings 55 and 56 described above are the tapered roller bearing 1 configured as described above.

  In that case, the rolling bearings 55 and 56 which are the two tapered roller bearings are assembled in a so-called outward combination. In order to define the relative positions of the rolling bearings 55 and 56, a cylindrical spacer 58 is interposed between the inner rings (reference numerals omitted).

  For reference, of the two rolling bearings 55 and 56, the one located on the upstream side in the power transmission direction, that is, on the flange joint 57 side is called the front side (or the tail side), and the downstream side in the power transmission direction, that is, the drive pinion gear. The side located on the 54 side is called the rear side (or head side). Generally, the rear-side rolling bearing 56 is larger in size than the front-side rolling bearing 55 and has a larger load capacity.

  By the way, between the outer peripheral surface of the outer end side of the drive pinion shaft 53 and the small end side inner peripheral surface of the front case 51a of the differential case 51, the oil leakage to the outside of the differential case 51 is prevented. An oil seal 59 is attached. Although not shown in detail in the drawing, the oil seal 59 is, for example, a type having a seal lip that contacts the outer peripheral surface of the flange joint 57 on the inner diameter side.

  The differential 50 described above employs an oil splash lubrication system in which the oil existing on the bottom side of the differential case 51 is splashed by the ring gear 52a and guided to the annular space between the pair of rolling bearings 55 and 56. .

  As shown in the drawing, an oil supply path 51 c is provided at the top of the upper half of the front case 51 a of the differential case 51. The oil supply path 51c receives oil splashed by the ring gear 52a, and then discharges the oil above the annular space between the pair of rolling bearings 55 and 56.

  Although not shown, in order to return the oil existing upstream of the front-side rolling bearing 55 to the rear case 51b side of the differential case 51 at a predetermined position on one side of the front case 51a of the differential case 51. The oil reflux path is provided.

  In such a differential 50, if at least one of the pair of rolling bearings 55 and 56 that support the drive pinion shaft 53 is the tapered roller bearing 1 of the above-described embodiment, the oil stirring resistance by the bearing is reduced. Therefore, it is advantageous to reduce the torque of the differential 50.

  In addition, this invention is not limited only to the said embodiment, All the deformation | transformation and application included in the range equivalent to the claim and the said range are possible. Examples are given below.

  (1) The present invention is not limited to the single row type tapered roller bearing 1 as described in the above embodiment, but can be applied to a double row type tapered roller bearing.

  (2) The application target of the tapered roller bearing 1 of the present invention is not limited to the differential as described in the above embodiment, but also includes a tapered roller bearing used for supporting a rotating shaft of other automotive equipment. In addition, tapered roller bearings used for supporting the rotating shafts of various machine tools can be cited as examples.

  (3) In the above embodiment, the inner ring 2 is provided with the small collar part 2b, but a tapered roller bearing using the inner ring 2 not provided with the small collar part 2b is also included in the present invention. .

  (4) In the above embodiment, an example in which the outer peripheral surface of the small-diameter cylindrical portion 2c of the inner ring 2 and the extension portion 5b of the cage 5 are arranged along the rotation axis O is given. It is also possible to form it with an appropriate inclination with respect to the axis O.

It is sectional drawing of the upper half which shows one Embodiment of the tapered roller bearing which concerns on this invention. It is the figure which looked at the tapered roller bearing of FIG. 1 from the small diameter end side of the inner ring. It is a perspective view which shows simply the holder | retainer single-piece | unit of FIG. It is an arrow view of the (4)-(4) line cross section of FIG. It is a figure for demonstrating the distribution | circulation route etc. of the oil in the tapered roller bearing of FIG. It is a differential for motor vehicles which is an example of the use object of the tapered roller bearing which is one embodiment of the present invention, and is the figure made the section in the lengthwise direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tapered roller bearing 2 Inner ring 2b Inner ring small flange part 2c Inner ring small diameter cylindrical part 3 Outer ring 4 Tapered roller 5 Cage 5b Cage extension part 5c Cage annular wall part 6 Cage passage 50 Differential 51 Differential case 51a Front case 51b Rear case 52 Differential transmission mechanism 52a Ring gear 53 Drive pinion shaft 54 Drive pinion gear 55 Front side rolling bearing 56 Rear side rolling bearing

Claims (5)

A tapered roller bearing in which a plurality of tapered rollers held by a substantially tapered cylindrical cage are arranged between an inner ring and an outer ring so as to be able to roll in the circumferential direction,
An extension portion is provided at the small diameter side end portion of the retainer so as to be opposed to the outer peripheral surface of the small diameter side end portion of the inner ring so as to be a non-contact sealing portion, and the axial dimension of the extension portion is , Is set larger than the thickness of the cage,
A tapered roller bearing, wherein the cage is provided with a passage through which the lubricant can flow inside and outside the bearing. The tapered roller bearing according to claim 1,
A small flange portion that restricts axial movement of the tapered roller is provided at the small diameter side end portion of the inner ring, and a small diameter cylindrical portion that is smaller in diameter than the small flange portion on the axially outer side from the small flange portion. Is provided,
A tapered roller bearing characterized in that the extension portion of the cage is formed in a cylindrical shape so as to be opposed to and parallel to the small diameter cylindrical portion of the inner ring. The tapered roller bearing according to claim 1 or 2,
The tapered roller bearing is characterized in that the passage is a hole penetrating in an axial direction in an annular wall portion that connects the main body portion of the cage and the extension portion and extends radially outward. In the tapered roller bearing according to any one of claims 1 to 3,
The main body portion of the retainer is brought close to the outer ring side, and the retainer is guided by the tapered rollers so as not to contact the inner and outer rings,
A tapered roller having a relationship of X> Y, where X is a facing gap between the extension portion of the cage and the small diameter side end portion of the inner ring and Y is a guide gap of the cage. bearing. In the differential case, the drive pinion shaft is rotatably supported by two axially separated rolling bearings, and the oil in the differential case is supplied from between the axially opposite sides of the both rolling bearings. A differential that is lubricated in such a way that it flows back through the bearing,
The differential, wherein the rolling bearing disposed at least on the drive pinion gear side of the drive pinion shaft is the tapered roller bearing according to any one of claims 1 to 4.

Images