JP2018159411A - Conical roller bearing - Google Patents

Abstract

To provide a tapered roller bearing in which seizure hardly occurs between a large end surface of a tapered roller and a large collar of an inner ring when the tapered roller bearing is stopped for a long time and thereafter the tapered roller bearing is started. SOLUTION: An outer ring 2, an inner ring 3, a plurality of tapered rollers 4 incorporated between the outer ring 2 and the inner ring 3, and an annular cage 5 for holding a circumferential interval between the tapered rollers 4 are provided. The inner ring 3 has a large collar 9 that contacts the large end surface 11 of each tapered roller 4, and the cage 5 has a large-diameter-side annular portion 12, a small-diameter-side annular portion 13, and a plurality of column portions 14. In a tapered roller bearing in which a large diameter side pocket surface 16 facing the large end surface 11 of each tapered roller 4 is formed in the large diameter side annular portion 12, the large diameter side annular portion 12 has a large diameter side pocket surface 16. An oil retaining hole 20 is formed to open and hold the lubricating oil introduced by capillarity. [Selection] Figure 1

Description

  The present invention relates to a tapered roller bearing.

  Tapered roller bearings, which are bearings that can simultaneously support radial loads and axial loads, are often used in automobile transmissions and differential mechanisms. Tapered roller bearings include an outer ring, an inner ring arranged coaxially inside the outer ring, a plurality of tapered rollers incorporated in the circumferential direction between the outer ring and the inner ring, and a circumference of the plurality of tapered rollers. And an annular retainer for maintaining a distance in the direction. On the outer periphery of the inner ring, a large hook is formed for guiding the large end face of the tapered roller. When the bearing rotates, the large end face of the tapered roller and the large collar of the inner ring support a part of the axial load by contact with sliding.

  The taper roller bearing is lubricated by the splashing of the lubricating oil splashed by the rotation of the gear or the lubricating oil pumped from the oil pump. Here, when the bearing is rotating, the lubricating oil is continuously supplied from the outside to the tapered roller bearing, but when the bearing is stopped, the lubricating oil is not supplied from the outside to the tapered roller bearing. Stop. For this reason, when the tapered roller bearing is stopped for a long time, most of the lubricating oil adhering to the tapered roller bearing flows down, and then, when the tapered roller bearing is started, insufficient lubrication is likely to occur.

  Particularly, in recent years, in order to suppress energy loss caused by the stirring resistance of the lubricating oil, there is a tendency to use a low-viscosity lubricating oil or reduce the amount of lubricating oil in an automobile transmission or a differential mechanism. Therefore, when the tapered roller bearing is stopped for a long time, the amount of lubricating oil remaining in the tapered roller bearing tends to be excessive, and then when the tapered roller bearing starts, the large end face of the tapered roller and the inner ring There was a risk of seizure between the two.

International Publication No. 2011-062188

  By the way, as a tapered roller bearing that can lubricate between the large end surface of the tapered roller and the large collar of the inner ring even when the supply of lubricating oil to the tapered roller bearing from the outside is stopped, the one described in Patent Document 1 is disclosed. Are known. The tapered roller bearing retainer of Patent Document 1 includes a large-diameter side annular portion that extends in the circumferential direction along the large end surface of the tapered roller, a small-diameter side annular portion that extends in the circumferential direction along the small end surface of each tapered roller, It has a plurality of pillars connecting the large-diameter side annular part and the small-diameter side annular part, and a plurality of oil retaining recesses are formed on the inner periphery of the large-diameter side annular part at intervals in the circumferential direction. .

  In the tapered roller bearing of Patent Document 1, when lubricating oil is continuously supplied to the tapered roller bearing from the outside, part of the lubricating oil is retained on the inner periphery of the large-diameter annular portion of the cage. When the supply of lubricating oil from the outside to the tapered roller bearing is stopped for some reason after that, the lubricating oil flowing out from the oil retaining recess on the inner circumference of the large-diameter side annular portion of the cage, Lubricate between the large end face of the tapered roller and the large collar of the inner ring.

  The inventor of the present application prevents the seizure between the large end face of the tapered roller and the large collar of the inner ring when the tapered roller bearing is stopped for a long time and then the tapered roller bearing starts. As in the above-mentioned Patent Document 1, it has been considered to form a plurality of oil retaining recesses for storing lubricating oil at intervals in the circumferential direction on the inner periphery of the large-diameter side annular portion of the cage.

  That is, if a plurality of oil retaining recesses for storing lubricating oil are formed at intervals in the circumferential direction on the inner periphery of the large-diameter annular portion of the cage, the tapered roller bearing stops for a long time, and then the tapered roller bearing. Is started, the lubricating oil accumulated in the holding recess can lubricate between the large end face of the tapered roller and the large collar of the inner ring.

  However, even if a plurality of oil retaining recesses for storing lubricating oil are formed at intervals in the circumferential direction on the inner periphery of the large-diameter side annular portion of the cage, there are the following problems. That is, when the tapered roller bearing is arranged in a direction in which the rotation shaft is horizontal and the tapered roller bearing is stopped, all of the oil retaining recesses formed on the inner periphery of the large-diameter side annular portion of the cage are Of these, only about 1/4 of the oil retaining recess (that is, the direction in which the oil retaining recess opens upward) comes down when the bearing is stopped, and the remaining 3 can be retained. For the oil retaining recess of about / 4, since the opening direction of the oil retaining recess is horizontal or downward, the lubricating oil in the oil retaining recess falls due to gravity, and the lubricating oil cannot be retained in the oil retaining recess. .

  For this reason, when the tapered roller bearing is stopped for a long time and then the tapered roller bearing is started, the gap between the large end face of the tapered roller and about 1/4 of the tapered roller is not maintained. Even if it can be lubricated with the lubricating oil accumulated in the oil recess, it cannot be lubricated between the large end face of the remaining 3/4 tapered rollers and the large collar of the inner ring. There was a risk of seizure between the end face and the inner ring.

  The problem to be solved by the present invention is that when the tapered roller bearing is stopped for a long time and then the tapered roller bearing is started, the tapered roller hardly causes seizure between the large end surface of the tapered roller and the large collar of the inner ring. It is to provide a bearing.

In order to solve the above problems, the present invention provides a tapered roller bearing having the following configuration.
Outer ring,
An inner ring arranged coaxially inside the outer ring;
A plurality of tapered rollers incorporated between the outer ring and the inner ring at intervals in the circumferential direction;
An annular retainer for retaining a circumferential interval between the plurality of tapered rollers,
The inner ring has a large hook that contacts the large end surface of each tapered roller,
The retainer includes a large-diameter annular portion extending in the circumferential direction along the large end face of each tapered roller, a small-diameter annular portion extending in the circumferential direction along the small end face of each tapered roller, and the large-diameter side. An annular portion and a plurality of column portions connecting the small-diameter-side annular portion, and the large-diameter-side annular portion, the small-diameter-side annular portion, and the plurality of column portions each accommodate the plurality of tapered rollers. In the tapered roller bearing in which a large-diameter side pocket surface facing the large end surface of each tapered roller is formed in the large-diameter side annular portion.
A tapered roller bearing characterized in that an oil retaining hole is formed in the large-diameter side annular portion so as to open in the large-diameter side pocket surface and introduce and hold lubricating oil by capillary action.

  In this way, when the tapered roller bearing is rotating, the lubricating oil is introduced into the oil retaining hole by capillary action, and then when the tapered roller bearing stops, the lubricating oil in the oil retaining hole drops due to gravity. Without being held in the oil retaining hole by capillary action. After that, when the tapered roller bearing is started, the lubricating oil in the oil retaining hole flows out of the oil retaining hole by centrifugal force and is supplied to the large end face of the tapered roller. Therefore, when the tapered roller bearing is stopped for a long time and then the tapered roller bearing is started, seizure between the large end surface of the tapered roller and the large collar of the inner ring can be effectively prevented.

  It is preferable that the oil retaining hole is formed by penetrating the large-diameter side annular portion in the cage axial direction.

  In this case, the oil retaining hole has an end opening on the side facing the large end face of the tapered roller and an end opening on the opposite side, and the lubricating oil is caused by capillary action on one end of the oil retaining hole. When flowing into the part opening, the air inside the oil retaining hole is discharged from the other end opening of the oil retaining hole. Therefore, it becomes easy for the lubricating oil to enter the oil retaining hole due to the capillary phenomenon.

  The oil retaining hole is preferably formed so that the inner dimension of the oil retaining hole along the radial direction of the cage is 2 mm or less at the maximum.

  In this case, the surface tension of the lubricating oil becomes dominant inside the oil retaining hole, so that the lubricating oil can be effectively retained in the oil retaining hole.

  The oil retaining hole is preferably formed so as to be inclined so that the portion of the inner surface of the oil retaining hole that faces the inner side in the cage radial direction is displaced toward the outer diameter side of the tapered roller as it approaches the large end surface of the tapered roller.

  If it does in this way, when a bearing starts, the lubricating oil inside an oil retaining hole will flow in the direction which approaches the large end surface of a tapered roller along the inclination of the inner surface of a retaining hole by centrifugal force. Therefore, when the tapered roller bearing is started, the large end surface of the tapered roller can be effectively lubricated.

  The oil retaining hole may have a tapered shape in which the inner dimension of the oil retaining hole along the radial direction of the cage gradually increases as it approaches the large end surface of the tapered roller.

  In this way, when the lubricating oil inside the oil retaining hole flows by centrifugal force, it smoothly flows in a direction approaching the large end surface of the tapered roller, and the large end surface of the tapered roller can be more effectively lubricated. It becomes possible. Further, when the cage is resin-molded with a mold, the oil retaining hole can be molded simultaneously with the mold of the cage.

  The oil retaining hole is preferably a round hole having a circular cross section.

  In this way, since the round hole has a shape in which the surface tension is not easily broken, the lubricating oil can be effectively held in the oil retaining hole by the surface tension.

  The large-diameter side pocket surface is formed so as to be inclined with respect to the direction perpendicular to the axis of the cage so as to come into surface contact with the large end surface of the tapered roller, and the oil retaining hole is formed on the center line of the plurality of tapered rollers. It is preferable to open at the position of a perpendicular line from the intersection point to the large-diameter side pocket surface.

  If it does in this way, an oil retaining hole will open in the position which contacts the large end surface of a tapered roller of a large diameter side pocket surface. Therefore, it is possible to effectively lubricate the large end face of the tapered roller.

  What was formed with resin can be employ | adopted for the said holder | retainer. In this way, when the cage is resin-molded with a mold, the oil retaining holes can be molded simultaneously with the mold of the cage, so that the cost is low.

  When the tapered roller bearing of the present invention is used, when the tapered roller bearing is rotating, the lubricating oil is introduced into the oil retaining hole by capillary action, and then when the tapered roller bearing stops, the lubricating oil in the oil retaining hole is lubricated. Oil does not fall due to gravity, but is held in the oil retaining hole by capillary action. After that, when the tapered roller bearing is started, the lubricating oil in the oil retaining hole flows out of the oil retaining hole by centrifugal force and is supplied to the large end face of the tapered roller. Therefore, when the tapered roller bearing is stopped for a long time and then the tapered roller bearing is started, seizure between the large end surface of the tapered roller and the large collar of the inner ring can be effectively prevented.

Sectional drawing along the axial plane of the tapered roller bearing of embodiment of this invention 1 is an enlarged sectional view in the vicinity of the oil retaining hole in FIG. Partial sectional view of the cage shown in FIG. 1 as seen from the outer diameter side 3 is a perspective view of the cage shown in FIG. The figure explaining the state which has arrange | positioned the oil retaining hole in the position of the perpendicular drawn from the intersection of the centerline of the tapered roller shown in FIG. 1 to the large diameter side pocket surface Enlarged sectional view of the vicinity of the oil retaining hole of the tapered roller bearing shown in FIG. (A) is a figure which shows the state which closed the pair of metal mold | die which carries out injection molding of the holder | retainer shown in FIG. 1, (b) is a figure which shows the state which opened the pair of metal mold | die shown to (a). The figure which shows an example of the transmission using the tapered roller bearing shown in FIG. The figure which shows an example of the differential mechanism using the tapered roller bearing shown in FIG.

  FIG. 1 shows a tapered roller bearing 1 according to an embodiment of the present invention. The tapered roller bearing 1 includes an outer ring 2, an inner ring 3 disposed coaxially on the inner side of the outer ring 2, a plurality of tapered rollers 4 incorporated between the outer ring 2 and the inner ring 3 at intervals in the circumferential direction, And an annular cage 5 that holds the circumferential intervals of the plurality of tapered rollers 4.

  A tapered outer ring raceway surface 6 is formed on the inner periphery of the outer ring 2. On the outer periphery of the inner ring 3, a tapered inner ring raceway surface 7 diametrically opposed to the outer ring raceway surface 6, a small flange 8 positioned on the small diameter side of the inner ring raceway surface 7, and a large diameter side of the inner ring raceway surface 7 A large ridge 9 is formed. The tapered roller 4 is in rolling contact with the outer ring raceway surface 6 and the inner ring raceway surface 7.

  The gavel 8 is formed to protrude from the inner ring raceway surface 7 to the outer diameter side so as to face the small end surface 10 of the tapered roller 4. The gavel 8 restricts the tapered roller 4 from moving to the small diameter side, and prevents the tapered roller 4 from falling off the inner ring raceway surface 7. The large flange 9 is formed to project from the inner ring raceway surface 7 to the outer diameter side so as to face the large end surface 11 of the tapered roller 4. During rotation of the bearing, the large end surface 11 of the tapered roller 4 and the large collar 9 of the inner ring 3 support a part of the axial load by contact with sliding.

  The cage 5 includes a large-diameter side annular portion 12 that extends in the circumferential direction along the large end surface 11 of each tapered roller 4, a small-diameter side annular portion 13 that extends in the circumferential direction along the small end surface 10 of each tapered roller 4, and A plurality of column portions 14 that connect between the large-diameter side annular portion 12 and the small-diameter side annular portion 13 through the tapered rollers 4 adjacent in the circumferential direction are provided.

  As shown in FIGS. 3 and 4, the large-diameter side annular portion 12, the small-diameter side annular portion 13, and the plurality of column portions 14 define a plurality of pockets 15 that respectively accommodate the plurality of tapered rollers 4. Here, the large-diameter side annular portion 12 and the small-diameter side annular portion 13 define both ends of the pocket 15 in the cage axial direction, and the column portion 14 defines both ends of the pocket 15 in the cage circumferential direction. A large-diameter side pocket surface 16 facing the large end surface 11 of the tapered roller 4 is formed in the large-diameter side annular portion 12, and a small-diameter side pocket facing the small end surface 10 of the tapered roller 4 is formed in the small-diameter side annular portion 13. A surface 17 is formed. The column portion 14 has a roller guide surface 18 that contacts the outer periphery of the tapered roller 4 and a triangular recess 19 that is recessed with respect to the roller guide surface 18 at a position facing the outer periphery of the tapered roller 4.

  As shown in FIG. 2, the triangular concave portion 19 has a corner where the large-diameter side pocket surface 16 and the pillar portion 14 intersect as one side when viewed in the circumferential direction of the cage 5, and the small-diameter-side annular portion 13 extends from the one side. It is a triangular-shaped recessed part whose height in the cage radial direction gradually decreases as it approaches. When viewed in the circumferential direction of the cage 5, one side of the triangular recess 19 on the cage outer diameter side coincides with the outer circumference of the cage 5, and one side of the triangular recess 19 on the cage inner diameter side is parallel to the cage axial direction. It extends to.

  The large-diameter side pocket surface 16 has an oil retaining hole 20 for introducing and holding lubricating oil by a capillary phenomenon. The oil retaining hole 20 is formed so as to penetrate the large-diameter-side annular portion 12 in the cage axial direction (left-right direction in the drawing), the end opening 21 on the side facing the large end surface 11 of the tapered roller 4, and the opposite Side end opening 22.

  As shown in FIG. 4, the oil retaining hole 20 is a round hole having a circular cross section. A plurality (three in the figure) of oil retaining holes 20 are provided at intervals in the circumferential direction of the cage for each large-diameter side pocket surface 16. Further, the oil retaining holes 20 are provided in all the large diameter side pocket surfaces 16 provided over the entire circumference of the large diameter side annular portion 12.

  As shown in FIGS. 5 and 6, the large-diameter side pocket surface 16 is formed so as to be inclined with respect to a direction perpendicular to the axis of the cage 5 (vertical direction in the drawing) so as to come into surface contact with the large end surface 11 of the roller. ing. The oil retaining hole 20 is opened at a position of a perpendicular H that is lowered from the intersection O of the center lines L of the plurality of tapered rollers 4 to the large-diameter side pocket surface 16. In the example shown in FIG. 6, the perpendicular H passes through the center of the oil retaining hole 20 (round hole with a circular cross section).

  As shown in FIG. 6, the oil retaining hole 20 gradually increases as the inner dimension d of the oil retaining hole 20 along the radial direction (vertical direction in the figure) of the cage 5 approaches the large end surface 11 of the tapered roller 4. The taper shape increases. Here, in the oil retaining hole 20, a portion 23 of the inner surface of the oil retaining hole 20 that faces inward in the radial direction of the cage 5 is displaced toward the outer diameter side of the cage 5 as it approaches the large end surface 11 of the tapered roller 4. It is formed so as to be inclined. Further, in the oil retaining hole 20, a portion 24 of the inner surface of the oil retaining hole 20 that faces the radially outer side of the cage 5 is parallel to the axial direction of the cage 5 (that is, parallel to the direction of the central axis of the tapered roller bearing 1). ). In the figure, an example is shown in which the portion 24 of the inner surface of the oil retaining hole 20 that faces the outer side in the radial direction of the cage 5 is formed in parallel with the axial direction of the cage 5. It is also possible to form the portion 24 facing the radially outer side of the cage 5 so as to be displaced toward the inner diameter side of the cage 5 as it approaches the large end surface 11 of the tapered roller 4.

  In the oil retaining hole 20, the inner dimension d1 in the cage radial direction of the end opening 21 on the side facing the large end surface 11 of the tapered roller 4 of the oil retaining hole 20 is set to 2 mm or less (preferably 1.5 mm or less). ing. That is, the oil retaining hole 20 is formed such that the inner dimension d of the oil retaining hole 20 along the radial direction of the cage 5 is 2 mm or less (preferably 1.5 mm or less) at the maximum.

  The oil retaining hole 20 has an inner dimension d2 of the end opening 22 opposite to the side facing the large end surface 11 of the tapered roller 4 of the oil retaining hole 20 in the cage radial direction of 0.5 mm or more (preferably 1.0 mm or more). That is, the oil retaining hole 20 is formed such that the inner dimension d of the oil retaining hole 20 along the radial direction of the cage 5 is 0.5 mm or more (preferably 1.0 mm or more). The oil retaining hole 20 is formed such that the inner dimension d1 of the end opening 21 is larger than the inner dimension d2 of the end opening 22 (d1> d2).

  The cage 5 is formed of a synthetic resin and is integrally formed with no joint. As the synthetic resin constituting the cage 5, polyamide (for example, PA66 or PA46) can be employed. When polyamide is used, since the polyamide has a relatively high lipophilicity, the lubricating oil is easily adapted to the inner surface of the oil retaining hole 20, and the lubricating oil can be effectively retained in the oil retaining hole 20 by the surface tension of the lubricating oil. It becomes possible. Instead of polyamide, polyphenylene sulfide (PPS), polyether ether ketone (PEEK), or the like can be employed. Further, a fiber reinforcing material (glass fiber, carbon fiber, aramid fiber or the like) is added to the synthetic resin constituting the cage 5.

  As shown in FIGS. 7A and 7B, the cage 5 can be resin-molded with two molds 25 and 26 that can be separated in the axial direction of the cage 5. Here, the small-diameter side pocket surface 17 and the guide surface 18 of the cage 5 shown in FIGS. 3 and 4 are formed by the first mold 25 shown in FIGS. 7 (a) and 7 (b). 4, the large-diameter side pocket surface 16, the triangular recess 19, and the oil retaining hole 20 of the cage 5 are formed by the second mold 26 shown in FIGS. 7A and 7B. In the second mold 26, an axial projection 28 having the same shape as the oil retaining hole 20 is formed on a surface 27 corresponding to the large-diameter side pocket surface 16. Since the axial protrusion 28 has a tapered shape in accordance with the dimensional relationship d1> d2 of the inner dimension of the end opening of the oil retaining hole 20, the cage 5 is molded into the mold 25, after the cage 5 is resin-molded. It is easy to extract from 26.

  FIG. 8 shows an example in which the tapered roller bearing 1 is used as a rolling bearing that rotatably supports the rotation shafts (in this case, the input shaft 31 and the output shaft 32) of the transmission 30 of the automobile. The transmission 30 includes an input shaft 31 to which engine rotation is input, an output shaft 32 provided in parallel with the input shaft 31, a plurality of gear trains 33 that transmit the rotation from the input shaft 31 to the output shaft 32, The gear train 33 includes a plurality of clutches 34 incorporated between the gear train 33 and the input shaft 31 or the output shaft 32, and the gear train 33 to be used is switched by selectively engaging the clutch 34. Thus, the transmission gear ratio transmitted from the input shaft 31 to the output shaft 32 is changed. The rotation of the output shaft 32 is output to the output gear 35, and the rotation of the output gear 35 is transmitted to the differential mechanism 36. The differential mechanism 36 has a ring gear 37 that meshes with the output gear 35 of the transmission 30, and distributes rotation input from the output gear 35 to the ring gear 37 to a pair of axles 38 connected to left and right wheels (not shown). introduce. The input shaft 31 and the output shaft 32 are rotatably supported by the tapered roller bearing 1, respectively. The tapered roller bearing 1 is lubricated by the splash of lubricating oil generated by the lubricating oil accumulated in the housing 39 being splashed by the rotation of the ring gear 37.

  Here, when the tapered roller bearing 1 is rotating, since the ring gear 37 is also rotating, the lubricating oil is continuously supplied to the tapered roller bearing 1, but when the tapered roller bearing 1 is stopped. Since the ring gear 37 is also stopped, the supply of the lubricating oil to the tapered roller bearing 1 is stopped. Therefore, when the tapered roller bearing 1 is stopped for a long time, much of the lubricating oil adhering to the tapered roller bearing 1 flows down, and when the tapered roller bearing 1 is started thereafter, insufficient lubrication is likely to occur.

  In particular, in recent years, in order to suppress energy loss caused by the stirring resistance of the lubricating oil, low-viscosity lubricating oil tends to be used or the amount of lubricating oil tends to be reduced in the transmission 30 and the differential mechanism 36 of the automobile. Therefore, when the tapered roller bearing 1 is stopped for a long time, the amount of lubricating oil remaining in the tapered roller bearing 1 tends to be excessive, and then when the tapered roller bearing 1 is started, the large end face 11 of the tapered roller 4 is started. There is a possibility that seizure occurs between the inner ring 3 and the large collar 9 of the inner ring 3 (see FIG. 1).

  With respect to this problem, in the tapered roller bearing 1 of this embodiment, when the tapered roller bearing 1 is rotating, lubricating oil is introduced into the oil retaining hole 20 by capillary action. Thereafter, when the tapered roller bearing 1 is stopped, as shown in FIG. 2, the lubricating oil in the oil retaining hole 20 does not fall due to gravity but is held in the oil retaining hole 20 by capillary action. Thereafter, when the tapered roller bearing 1 is started, the lubricating oil in the oil retaining hole 20 flows out of the oil retaining hole 20 due to centrifugal force, as indicated by the chain line arrow in FIG. 2, and reaches the large end surface 11 of the tapered roller 4. Supplied. Therefore, seizure between the large end surface 11 of the tapered roller 4 and the large collar 9 of the inner ring 3 is effectively prevented when the tapered roller bearing 1 is stopped for a long time and then the tapered roller bearing 1 is started. Can do.

  Further, the tapered roller bearing 1 employs a through hole that penetrates the large-diameter annular portion 12 in the cage axial direction as an oil retaining hole 20 for retaining the lubricating oil by a capillary phenomenon. When oil flows into one end opening 21 of the oil retaining hole 20, the air inside the oil retaining hole 20 is discharged from the other end opening 22 of the oil retaining hole 20. Therefore, the lubricating oil tends to enter the oil retaining hole 20 due to a capillary phenomenon.

  Further, in the tapered roller bearing 1, the oil retention hole 20 along the radial direction of the cage 5 has an inner dimension d set to 2 mm or less (preferably 1.5 mm or less) at the maximum. The surface tension of the lubricating oil is dominant with respect to the gravity acting on the lubricating oil, and the lubricating oil can be effectively held in the oil retaining hole 20.

  Further, the tapered roller bearing 1 is displaced toward the outer diameter side of the cage 5 as the portion 23 facing the radially inner side of the cage 5 in the inner surface of the oil retaining hole 20 approaches the large end surface 11 of the tapered roller 4. Therefore, when the tapered roller bearing 1 is started, the lubricating oil inside the oil retaining hole 20 is moved along the inclination of the inner surface of the oil retaining hole 20 by centrifugal force. It flows in the direction approaching. Therefore, when the tapered roller bearing 1 is started, the large end surface 11 of the tapered roller 4 can be effectively lubricated.

  Further, the tapered roller bearing 1 has a tapered shape in which the inner dimension d of the oil retaining hole 20 along the radial direction of the cage 5 gradually increases as it approaches the large end surface 11 of the tapered roller 4. When the lubricating oil inside the oil retaining hole 20 flows by centrifugal force, it smoothly flows in a direction approaching the large end surface 11 of the tapered roller 4, and the large end surface 11 of the tapered roller 4 can be more effectively lubricated. It is possible. Further, when the cage 5 is resin-molded with the molds 25 and 26, the oil retaining hole 20 can be molded simultaneously with the molds 25 and 26 of the cage 5.

  Further, since the tapered roller bearing 1 employs a round hole with a circular cross section having a shape in which the surface tension is not easily broken as the oil retaining hole 20, the lubricating oil is effectively retained in the oil retaining hole 20 by the surface tension. It is possible to do.

  Further, the tapered roller bearing 1 has a large diameter because the oil retaining hole 20 is opened at a position of a perpendicular line H extending from the intersection O of the center lines L of the plurality of tapered rollers 4 to the large-diameter side pocket surface 16. The oil retaining hole 20 is opened at a position of the side pocket surface 16 in contact with the large end surface 11 of the tapered roller 4, so that the large end surface 11 of the tapered roller 4 can be effectively lubricated.

  Further, the tapered roller bearing 1 can form the oil retaining hole 20 simultaneously with the molds 25 and 26 of the cage 5 when the cage 5 is resin-molded with the molds 25 and 26. Cost.

  In FIG. 8, the tapered roller bearing 1 is lubricated by the splashing of the lubricating oil splashed by the rotation of the ring gear 37. However, the lubricating oil is pumped from an oil pump driven by the engine, and the lubricating oil is supplied from a nozzle (not shown) to the housing 39. It is also possible to inject the tapered roller bearing 1 with the injected lubricating oil.

  The above tapered roller bearing 1 can also be used as a rolling bearing that rotatably supports the input shaft of the differential mechanism 40 shown in FIG. The differential mechanism 40 is arranged with an input shaft 41 connected to a propeller shaft (not shown) for transmitting the rotation of the engine, a drive pinion 42 fixed to the input shaft 41, and spaced in the axial direction. A differential case 44 rotatably supported by a pair of bearings 43, a ring gear 45 fixed to the differential case 44 coaxially with the rotational center of the differential case 44, and meshing with the drive pinion 42, and a differential case in a direction perpendicular to the rotational center of the differential case 44 44, a pinion shaft 46 fixed to 44, a pair of pinions 47 rotatably supported on the pinion shaft 46, and a pair of left and right side gears 48 meshing with the pair of pinions 47. An axle 49 connected to the left wheel is connected to the left side gear 48, and an axle 49 connected to the right wheel is connected to the right side gear 48. The differential mechanism 40 distributes and transmits the rotation input from the propeller shaft to the input shaft 41 to the pair of left and right axles 49. The input shaft 41 of the differential mechanism 40 is disposed in a direction orthogonal to the rotation center line of the ring gear 45, and the input shaft 41 is rotatably supported by the tapered roller bearing 1. The tapered roller bearing 1 is lubricated by the splash of lubricating oil generated by the lubricating oil accumulated in the housing 50 being splashed by the rotation of the ring gear 45.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Tapered roller bearing 2 Outer ring 3 Inner ring 4 Tapered roller 5 Cage 9 Large collar 10 Small end surface 11 Large end surface 12 Large diameter side annular portion 13 Small diameter side annular portion 14 Column portion 15 Pocket 16 Large diameter side pocket surface 20 Oil retaining hole 23 The part of the inner surface of the oil retaining hole facing the inner side of the cage radial direction d The inner dimension L of the oil retaining hole Center line O of the tapered roller O Intersection H Perpendicular

Claims (8)

Outer ring (2),
An inner ring (3) arranged coaxially inside the outer ring (2);
A plurality of tapered rollers (4) incorporated in the circumferential direction between the outer ring (2) and the inner ring (3);
An annular retainer (5) for retaining a circumferential interval between the plurality of tapered rollers (4),
The inner ring (3) has a large collar (9) that contacts the large end surface (11) of each tapered roller (4),
The cage (5) includes a large-diameter-side annular portion (12) extending in the circumferential direction along the large end surface (11) of each tapered roller (4), and a small end surface (10) of each tapered roller (4). ) Having a small-diameter-side annular portion (13) extending in the circumferential direction along the circumferential direction, and a plurality of pillar portions (14) connecting the large-diameter-side annular portion (12) and the small-diameter-side annular portion (13), The large-diameter-side annular portion (12), the small-diameter-side annular portion (13), and the plurality of column portions (14) define a plurality of pockets (15) that respectively accommodate the plurality of tapered rollers (4). In the tapered roller bearing, the large-diameter side annular portion (12) is provided with a large-diameter side pocket surface (16) facing the large end surface (11) of each tapered roller (4).
The large-diameter-side annular portion (12) is formed with an oil retaining hole (20) that opens to the large-diameter-side pocket surface (16) and introduces and holds lubricating oil by capillary action. Tapered roller bearing.   The tapered roller bearing according to claim 1, wherein the oil retaining hole (20) is formed so as to penetrate the large-diameter-side annular portion (12) in the cage axial direction.   The cone according to claim 1 or 2, wherein the oil retaining hole (20) is formed such that the inner dimension (d) of the oil retaining hole (20) along the radial direction of the cage is 2 mm or less at maximum. Roller bearing.   The oil retaining hole (20) is located on the inner surface of the oil retaining hole (20) so that the portion (23) facing the inner side in the cage radial direction is closer to the large end surface (11) of the tapered roller (4). The tapered roller bearing according to any one of claims 1 to 3, wherein the tapered roller bearing is formed to be inclined so as to be displaced toward a radial side.   The oil retaining hole (20) has a taper that gradually increases as the inner dimension (d) of the oil retaining hole (20) along the radial direction of the cage approaches the large end surface (11) of the tapered roller (4). The tapered roller bearing according to claim 4, wherein the tapered roller bearing has a shape.   The tapered roller bearing according to any one of claims 1 to 5, wherein the oil retaining hole (20) is a round hole having a circular cross section. The large-diameter side pocket surface (16) is formed to be inclined with respect to the direction perpendicular to the axis of the cage (5) so as to come into surface contact with the large end surface (11) of the tapered roller (4),
The oil retaining hole (20) opens at a position of a vertical line (H) extending from the intersection (O) of the center line (L) of the plurality of tapered rollers (4) to the large-diameter side pocket surface (16). The tapered roller bearing according to any one of claims 1 to 6.   The tapered roller bearing according to any one of claims 1 to 7, wherein the cage (5) is made of resin.

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