JP7272175B2 - tapered roller bearing - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tapered roller bearing, and more particularly to a tapered roller bearing in which lubricating oil is supplied to the inside of the bearing.

In recent years, as in the transmission of some hybrid vehicles, a mechanism that stops the lubricating oil pump when the engine is stopped has appeared, which is likely to cause the problem of bearing seizure. In addition, when the vehicle is towed, the lubricating oil pump does not operate and the tires idle, which may cause seizure of the bearings in the transmission. Therefore, there is a demand for a bearing that can prevent seizure even in a lubricating environment in which lubricating oil is intermittently supplied or in a lubricating environment in which the amount of lubricating oil is very small.

As a conventional tapered roller bearing 100, as shown in FIGS. It is known to have a plurality of tapered rollers 113 that are rollably provided between the inner ring raceway surface 112a and a retainer 114 that holds the plurality of tapered rollers 113 at substantially equal intervals in the circumferential direction ( For example, see Patent Document 1).

Further, the retainer 114 includes a large-diameter side annular portion 115, a small-diameter side annular portion 116 arranged coaxially with the large-diameter side annular portion 115, and a large-diameter side annular portion 115 and a small-diameter side annular portion 116. are connected in the axial direction, and a plurality of pillars 117 are provided at substantially equal intervals in the circumferential direction. and a pocket 118 which is formed surrounded by and rollably holds the tapered rollers 113 . The tapered roller 113 has a rolling surface 113a provided on the peripheral surface of the tapered roller 113, a large diameter side end surface 113b provided on the large diameter side end of the tapered roller 113, and a small diameter side end of the tapered roller 113. and a small diameter side end face 113c provided.

Japanese Patent No. 6354242

In the tapered roller bearing 100 described in Patent Document 1, one oil groove 120 is formed in the axial direction inner end surface 115a of the large diameter side annular portion 115 of the retainer 114 along the circumferential direction. In order to increase the amount of lubricating oil stored inside the groove 120 , the radial width of the oil groove 120 is set to ⅓ of the radial width of the large-diameter side annular portion 115 . That is, for example, when the radial width of the large-diameter side annular portion 115 is 9 mm, the radial width of the oil groove 120 is 3 mm. In this case, since the oil groove 120 alone cannot generate capillary action to hold the lubricating oil, it is necessary to cover the oil groove 120 with the tapered rollers 113 as described in the above-mentioned Patent Document 1. there were.

However, as shown in FIG. 16, when the retainer 114 moves axially toward the large diameter side of the tapered rollers 113, the large diameter side end surfaces 113b of the tapered rollers 113 and the axial inner end surfaces of the large diameter side annular portions 115 115a became large, and the lubricating oil leaked out from the oil groove 120 without capillary action.

Furthermore, in the drawings of Patent Document 1, the large-diameter side end faces of the tapered rollers are described as flat, but as shown in FIGS. , and a recess 113d may be formed in the center of the large-diameter side end face 113b. In such a tapered roller 113, even if the axial clearance between the tapered roller 113 and the cage 114 is reduced, the clearance SP (Fig. 19 (see reference) was leaking lubricating oil.

The present invention has been made in view of the above-described problems, and its object is to suppress the leakage of lubricating oil from the oil groove, in a lubricating environment where the supply of lubricating oil is intermittent, or Another object of the present invention is to provide a tapered roller bearing capable of preventing seizure even in a lubricating environment with a very small amount of lubricating oil.

The above objects of the present invention are achieved by the following configurations.
(1) An outer ring having an outer ring raceway surface on its inner peripheral surface, an inner ring having an inner ring raceway surface on its outer peripheral surface, and a plurality of tapered rollers provided to roll between the outer ring raceway surface and the inner ring raceway surface. and a retainer that retains the plurality of tapered rollers at substantially equal intervals in the circumferential direction, wherein the retainer includes a large-diameter annular portion and a small-diameter annular portion coaxially arranged with the large-diameter annular portion. A side annular portion, the large diameter side annular portion and the small diameter side annular portion are axially connected to each other, and a plurality of column portions are provided at substantially equal intervals in the circumferential direction, and the column portions adjacent to each other in the circumferential direction. Pockets formed between the pillars for rollingly holding the tapered rollers, wherein the retainer is formed between the axial inner end surface of the small-diameter side annular portion and the tapered rollers. A first gap is provided between the large-diameter side end face and a second gap between the axial inner end face of the large-diameter side annular portion and the large-diameter side end face of the tapered roller, and the first gap is provided. and the dimensions of the second gap are each set to 0.3 mm or less, and at least one oil groove for storing lubricating oil is provided in the axial inner end surface of the large diameter side annular portion, and the oil groove is 2. A tapered roller bearing, wherein a large-diameter side end face of said tapered roller and an axially inner end face of said large-diameter side annular portion are provided so as to fit in an overlapping region in the longitudinal direction of said tapered roller.
(2) The large-diameter end face of the tapered roller includes a circular recess formed in the center of the large-diameter end face, and a circular recess provided around the recess, which is located within the axial direction of the large-diameter annular portion. an annular contact surface contactable with the end surface, wherein the annular contact surface and the axial inner end surface of the large-diameter side annular portion of the oil groove overlap in the longitudinal direction of the tapered roller. The tapered roller bearing according to (1), which is provided so as to fit within the area.
(3) The tapered roller bearing according to (2), wherein the oil groove is formed in an annular fan shape along the circumferential direction of the large diameter side annular portion.
(4) A pair of end connecting sides, which are both longitudinal sides of the oil groove, are formed in an arc shape following the outer peripheral edge of the annular contact surface of the tapered roller (3 ) tapered roller bearing.
(5) The tapered roller bearing according to (2), wherein the oil groove is formed in an annular fan shape along the annular contact surface of the tapered roller.
(6) An oil storage recess for storing lubricating oil is formed at a position where the recess of the tapered roller overlaps in the longitudinal direction of the tapered roller on the axial inner end surface of the large diameter side annular portion of the retainer. The tapered roller bearing according to (5), characterized by:
(7) The axial inner end surface of the large diameter side annular portion is formed in a concave spherical shape, the large diameter side end surface of the tapered roller is formed in a convex spherical shape, and the axial direction inner end surface of the large diameter side annular portion is formed in a convex spherical shape. The tapered roller bearing according to (1), wherein the concave spherical curvature radius SRy of the end face is set within ±10% of the convex spherical curvature radius Ra of the large diameter side end face of the tapered roller. .
(8) Any one of (1) to (7), characterized in that the lubricating oil is intermittently supplied to the inside of the bearing, or the lubricating oil inside the bearing is used in a very small amount. A tapered roller bearing as described in 1.

According to the present invention, an oil groove for storing lubricating oil is provided in the axial inner end surface of the large-diameter side annular portion of the retainer. Even so, the lubricating oil stored in the oil groove is supplied to the large-diameter side end faces of the tapered rollers. Therefore, seizure of the bearing can be prevented even in a lubricating environment in which lubricating oil is intermittently supplied or in a lubricating environment in which the amount of lubricating oil is very small. In addition, since the oil groove is provided in a region where the large-diameter end surface of the tapered roller and the axial inner end surface of the large-diameter annular portion of the retainer overlap in the longitudinal direction of the tapered roller, the oil groove is provided with the tapered roller. It is covered by the large-diameter side end face of the roller. Therefore, it is possible to suppress the leakage of lubricating oil from the oil groove.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing explaining one Embodiment of the tapered roller bearing which concerns on this invention. FIG. 3 is a plan view of the retainer and tapered rollers viewed from the radially outer side; FIG. 2 is a schematic view of the retainer shown in FIG. 1 as seen from the radially inner side; FIG. 4 is a schematic diagram showing the positional relationship between an oil groove and the large-diameter side end faces of tapered rollers. It is a mimetic diagram explaining the 1st modification of a retainer. It is a schematic diagram explaining the 2nd modification of a retainer. It is a schematic diagram explaining the 3rd modification of a retainer. It is a schematic diagram explaining the 4th modification of a retainer. It is a schematic diagram explaining the 5th modification of a retainer. It is a schematic diagram explaining the 6th modification of a retainer. FIG. 11 is a cross-sectional view for explaining a seventh modified example of the retainer; It is a schematic diagram corresponding to FIG. 4 of the holder|retainer of a 7th modification. FIG. 11 is a cross-sectional view for explaining an eighth modified example of the retainer; FIG. 4 is a cross-sectional view for explaining oil supply to bearings by a lubricating oil pump; FIG. 5 is a cross-sectional view for explaining oil supply to a bearing by splashing of a gear; FIG. 10 is a cross-sectional view illustrating a state in which the retainer of the conventional tapered roller bearing moves axially toward the large diameter side of the tapered rollers. FIG. 17 is a cross-sectional view for explaining when the retainer shown in FIG. 16 is axially moved to the smaller diameter side of the tapered rollers; FIG. 17 is a plan view of the retainer and tapered rollers shown in FIG. 16 viewed from the outside in the radial direction; FIG. 17 is a schematic diagram showing the contact positional relationship between the oil groove shown in FIG. 16 and the large-diameter side end surface of the tapered roller.

An embodiment of a tapered roller bearing according to the present invention will be described in detail below with reference to the drawings.

As shown in FIG. 1, the tapered roller bearing 10 of this embodiment includes an outer ring 11 having an outer ring raceway surface 11a on its inner peripheral surface, an inner ring 12 having an inner ring raceway surface 12a on its outer peripheral surface, an outer ring raceway surface 11a and an inner ring. It includes a plurality of tapered rollers 13 that are rotatably provided between them and the raceway surface 12a, and a retainer 14 that holds the plurality of tapered rollers 13 at substantially equal intervals in the circumferential direction. In this embodiment, lubricating oil circulating inside the housing H (see FIG. 14) is appropriately supplied to the inside of the bearings by a lubricating oil pump P (see FIG. 14) or the like.

The inner ring 12 has a large flange portion 12b provided at the large diameter side end portion of the inner ring 12 and a small flange portion 12c provided at the small diameter side end portion of the inner ring 12 . The outer peripheral surface of the inner ring 12 is formed in a substantially conical shape.

The tapered rollers 13 are provided on a rolling surface 13a provided on the peripheral surface of the tapered roller 13, a large diameter side end surface 13b provided on the large diameter side end of the tapered roller 13, and a small diameter side end of the tapered roller 13. and a small diameter side end face 13c. The large-diameter side end face 13b is formed in a convex spherical shape with a radius of curvature Ra, and a circular concave portion 13d is formed in the central portion thereof. The center of the convex spherical surface is positioned on the rotation axis of the tapered roller 13 .

The retainer 14 is made of synthetic resin and is injection-molded by axial draw. The diameter-side annular portion 15 and the small-diameter-side annular portion 16 are connected in the axial direction, and a plurality of pillars 17 are provided at substantially equal intervals in the circumferential direction. and a pocket 18 formed by being surrounded by the diameter-side annular portion 15 and the small-diameter-side annular portion 16 and holding the tapered roller 13 in a rollable manner.

Further, the retainer 14 has a first gap S1 between the axial inner end surface 16a of the small-diameter annular portion 16 of the retainer 14 and the small-diameter end surface 13c of the tapered roller 13 . Further, the retainer 14 has a second gap S2 between the axial inner end surface 15a of the large-diameter annular portion 15 of the retainer 14 and the large-diameter end surface 13b of the tapered roller 13 . Further, in the present embodiment, the axial dimension D1 of the first gap S1 and the axial dimension D2 of the second gap S2 are each set to 0.3 mm or less. The roller axial dimensions D1 and D2 are dimensions along the central axis (rotational axis) direction of the tapered rollers 13 .

In addition, the surface of the axial inner end surface (hereinafter also simply referred to as “pocket surface”) 15a of the large-diameter side annular portion 15 of the retainer 14 is formed to be rough. (Arithmetic mean roughness) is set to 3 μm to 20 μm.

The roughness of the pocket surface 15 a of the large-diameter side annular portion 15 functions to guide the lubricating oil stored in the oil groove 20 (to be described later) to the tapered rollers 13 . As a result, the oil retention capacity and oil supply capacity of the pocket surface 15a can be enhanced. Further, it is preferable that the inner surface of the oil groove 20, which will be described later, is also formed roughly in order to increase the oil retention capacity. In addition, since the pocket surface 15a is substantially perpendicular to the direction in which the retainer is removed from the mold, even if the pocket surface 15a is roughened, it does not hinder release from the mold after molding. The surface roughness of the pocket surface 15 a may be set for all the pockets 18 or may be set for some of the pockets 18 .

The pocket surface 15a of the large-diameter side annular portion 15 is formed in a concave spherical shape with a radius of curvature SRy. The radius of curvature SRy of the concave spherical surface of the pocket surface 15a is set within ±10% of the radius of curvature Ra of the convex spherical surface of the large-diameter side end surface 13b of the tapered roller 13 (0.9Ra≤SRy≤1). .1 Ra). As a result, the degree of close contact between the pocket surface 15a and the large-diameter side end surface 13b of the tapered roller 13 is improved, so that high oil retention and oil supply effects can be obtained. However, if SRy is matched with Ra (SRy=Ra) to achieve full contact, the frictional resistance will increase.

Further, as shown in FIGS. 1 to 4, one oil groove 20 for storing lubricating oil is formed in the pocket surface 15a of the large-diameter side annular portion 15 of the retainer 14. As shown in FIG. The oil groove 20 is a bottomed groove, and is formed in each pocket 18 in an annular fan shape along the circumferential direction of the large-diameter side annular portion 15 . The oil grooves 20 may be provided for all the pockets 18 or may be provided for some of the pockets 18 . Also, the number of oil grooves 20 is not limited to one, and may be two or more.

FIG. 4 is a schematic diagram showing the positional relationship between the oil groove 20 and the large-diameter end face 13b of the tapered roller 13. As shown in FIG. The large-diameter end surface 13b of the tapered roller 13 includes a circular recess 13d formed in the center of the large-diameter end surface 13b and an annular contact surface provided around the recess 13d and capable of contacting the pocket surface 15a. 13e. The oil groove 20 is formed so that the large-diameter side end surface 13b of the tapered roller 13 and the pocket surface 15a of the tapered roller 13 overlap each other in the longitudinal direction of the tapered roller 13 (the overlapping area when viewed in the longitudinal direction of the tapered roller 13). be provided. More specifically, the oil groove 20 is provided so that the annular contact surface 13e and the pocket surface 15a are accommodated in a region where the tapered rollers 13 overlap each other in the longitudinal direction. As a result, the oil groove 20 is covered with the annular contact surface 13e (the large-diameter side end surface 13b) of the tapered roller 13, so that the lubricant can be prevented from leaking out of the oil groove 20.

Further, the diameter of the concave portion 13d of this embodiment is formed smaller than that of a common tapered roller. In other words, the diameter of the recessed portion 13d of this embodiment is set to such a dimension that the recessed portion 13d and the oil groove 20 do not overlap in the longitudinal direction of the tapered rollers 13, including the radial movement amount of the retainer 14. there is

Further, as shown in FIG. 4, in this embodiment, the oil groove 20 is formed in an annular fan shape, and the pair of end connecting sides 21, which are both longitudinal sides of the oil groove 20, It is formed in an arc shape following the outer peripheral edge of the annular contact surface 13e. As a result, the capacity of the oil groove 20 for storing lubricating oil can be increased. The oil groove 20 formed by axial draw extends in the same direction (axial direction) as the center axis of the retainer 14, which is the direction in which the molding die moves (releases) during injection molding.

The retainer 14 is made of synthetic resin, and can be injection molded, for example, by axial drawing. The surface roughness of the pocket surface 15a of the large-diameter side annular portion 15 and the oil groove 20 can be simultaneously formed by this injection molding. In this case, there is no need to add a processing step, special molding such as two-color molding (double molding), or adhesion of a separately manufactured oil retaining member. Therefore, it is possible to improve the seizure resistance without substantially increasing the manufacturing cost.

Further, the material of the cage 14 is not particularly limited, and examples thereof include general cage resin materials such as nylon. The synthetic resin of the retainer 14 may contain fibers as a reinforcing agent.

As described above, according to the tapered roller bearing 10 of the present embodiment, the pocket surface 15a of the large-diameter side annular portion 15 of the retainer 14 is provided with the oil groove 20 for storing lubricating oil. Even if the lubricating oil is not supplied and the amount of lubricating oil in the bearing 10 becomes very small, the lubricating oil stored in the oil groove 20 is supplied to the large-diameter side end surfaces 13b of the tapered rollers 13 . Therefore, seizure of the bearing 10 can be prevented even in a lubricating environment in which lubricating oil is intermittently supplied or in a lubricating environment in which the amount of lubricating oil is very small. Further, since the oil groove 20 is provided so that the annular contact surface 13e of the tapered roller 13 and the pocket surface 15a of the tapered roller 13 overlap each other in the longitudinal direction of the tapered roller 13, the oil groove 20 is provided so that the annular contact surface 13e of the tapered roller 13 and the pocket surface 15a overlap each other. is covered by the contact surface 13e. Therefore, it is possible to suppress the leakage of lubricating oil from the oil grooves 20 .

Further, according to the tapered roller bearing 10 of the present embodiment, the oil groove 20 is formed along the circumferential direction, and the direction in which the centrifugal force acts during rotation of the bearing is perpendicular to the direction in which the oil groove 20 is formed. It is possible to suppress scattering of the lubricating oil contained in the space due to centrifugal force.

Moreover, according to the tapered roller bearing 10 of the present embodiment, the amount of lubricating oil can be greatly reduced, so that the stirring resistance of the lubricating oil can be reduced. In addition, for example, if a structure (see FIG. 15) is adopted in which even a small amount of lubricating oil can be supplied by splashing with gears, etc., the lubricating oil pump and oil supply passage can be eliminated, thereby making the entire lubrication system lightweight and compact. , the cost can be reduced.

Further, according to the tapered roller bearing 10 of the present embodiment, seizure can be prevented even in a lubricating environment in which lubricating oil is intermittently supplied into the bearing or the amount of lubricating oil in the bearing is very small. Performance and lubrication effect can be maintained for a long period of time. Therefore, the tapered roller bearing 10 of the present embodiment can be suitably used, for example, in a mechanism for temporarily stopping the lubricating oil pump when the engine is stopped, such as in the transmission of some hybrid vehicles. This makes it possible to cope with situations such as when the lubricating oil pump does not operate when the vehicle is being towed, making it difficult to supply a sufficient amount of lubricating oil.

Here, a lubricating environment in which a small amount of lubricating oil is used in this specification will be described. For example, in the case of transmissions for automobiles, there are generally two methods of supplying lubricating oil: pumping of lubricating oil by a lubricating oil pump P shown in FIG. 14 and splashing of lubricating oil by a gear G shown in FIG. known to

As a structure for pumping the lubricating oil by the lubricating oil pump P, as shown in FIG. A structure in which an oil supply passage R communicating with the bearing 10 is provided in H and a lubricating oil pump P is connected to the oil supply passage R is generally known. In the case of this structure, lubricating oil pressure-fed from the lubricating oil pump P is supplied to the bearing 10 via the oil supply passage R. As shown in FIG.

15, the outer ring 11 of the tapered roller bearing 10 is fitted inside the housing H, and the inner ring 12 is fitted around the rotating shaft A. A structure in which a gear G is provided adjacent to an inner ring 12 on an axis A is generally known. In the case of this structure, the lubricating oil adhering to the gear G scatters due to the centrifugal force accompanying the rotation of the shaft, and the splattered lubricating oil adheres to the bearing 10 and is supplied.

In the two structures described above, lubricating oil is supplied in an amount of about 50 cc/min to 1000 cc/min in order to prevent seizure of the bearing. If the amount of lubricating oil is less than 10 cc/min, heat generation and seizure tend to occur due to insufficient oil film due to insufficient lubricating oil. The present invention deals with a thin lubrication state rather than a non-lubricating state, and a large effect is obtained in a lubricating environment in which the amount of lubricating oil is very small, specifically in a thin lubrication state of about 0.01 cc / min to 10 cc / min. demonstrate.

Next, an environment in which lubricating oil is intermittently supplied in the present specification will be described. For example, a hybrid vehicle has a mode in which the vehicle is driven by an electric motor while the engine is stopped. In this mode, in a structure with only a lubricating oil pump directly connected to the engine, the vehicle runs without supplying lubricating oil to the bearings. As a result, the vehicle runs without oil for several minutes, but the bearing must not seize during this period. There is a need to extend this electric running time as the battery evolves. At present, some vehicle models control the engine to run at regular intervals to operate the lubricating oil pump in order to prevent seizure. In order to solve this problem, it is necessary to add an electric lubricating oil pump to the system, or adopt a non-lubricating, seizure-resistant bearing like the present invention. In the present invention, since the time until seizure is related to the amount of lubricating oil stored in the oil groove, it is possible to significantly extend the non-lubricating application time from several tens of minutes to several hours by increasing the amount of lubricating oil. It is possible. An increase in the amount of lubricating oil can be dealt with, for example, by increasing the number of oil grooves or increasing the depth of the oil grooves.

In addition, passenger cars are sometimes towed as auxiliary vehicles in the event of a breakdown or at the destination of a large vehicle such as a camper. In such a case, it is possible to prevent the vehicle from spinning by placing the driving wheels of the vehicle on a cart or the like, but in reality, there are cases where the vehicle is towed while the driving wheels are spinning. In this case, there is no drive transmission and the load on the bearing is light because it rotates idle without load. In this idling state, the engine and the electric lubricating oil pump do not operate, and the lubricating oil pump is stopped, so the bearings are likely to seize. As a countermeasure against this, some vehicle models have devised the drive system so that splashing refueling occurs. In the present invention, even if the lubricating oil pump stops, the bearing can be lubricated until the lubricating oil stored in the oil groove runs out. can be greatly improved.

In addition, when the engine is started in an extremely cold environment, the lubricating oil freezes, and a phenomenon temporarily occurs in which neither the lubricating oil pump nor the lubricating oil splashing occurs. In this case, until the frozen lubricating oil warms up and melts, the lubrication must be covered by the small amount of oil adhering to the bearing itself. Further, in the present invention, since the frozen lubricating oil is stored in the oil grooves, it is lubricated while gradually melting as the bearing heats up, so that seizure resistance can be dramatically improved.

Next, as a first modified example of the present embodiment, as shown in FIG. 5, the pair of end connecting sides 21 of the oil groove 20 may be formed in a linear shape along the radial direction.

As a second modification of the present embodiment, as shown in FIG. 6, the pair of end connecting sides 21 of the oil groove 20 may be formed in a semicircular shape.

Further, as a third modification of the present embodiment, as shown in FIG. The radial width D3 of the intermediate portion may be increased (formed into a substantially crescent shape). As a result, the capacity of the oil groove 20 to store lubricating oil can be further increased. The radial width D3 of the oil groove 20 is the width in the direction orthogonal to the extending direction of the oil groove 20 .

Further, as a fourth modification of the present embodiment, as shown in FIG. 8, it is not necessary to form the concave portion 13d in the large-diameter side end face 13b of the tapered roller 13. FIG.

As a fifth modification of the present embodiment, as shown in FIG. 9, the corners on the inner diameter side of the pair of end connecting sides 21 of the oil groove 20 may be chamfered Rx in an arc shape.

As a sixth modification of the present embodiment, as shown in FIG. 10, the corners on the inner diameter side of the pair of end connecting sides 21 of the oil groove 20 may be chamfered Cx in a straight line.

As a seventh modification of the present embodiment, the oil groove 20 may be formed in an annular fan shape along the annular contact surface 13e of the tapered roller 13, as shown in FIGS. In addition, in this modification, a semicircular oil storage recess 30 for storing lubricating oil is formed at a position in the pocket surface 15a of the retainer 14 that overlaps the recess 13d of the tapered roller 13 in the longitudinal direction of the tapered roller 13. . The oil storage recess 30 is formed smaller than the recess 13d. The oil storage recessed portion 30 also opens to the inner peripheral surface of the large-diameter side annular portion 15 . According to this modification, the lubricating oil stored in the oil storage recess 30 in addition to the oil groove 20 can supply a large amount of lubricating oil in case of a momentary shortage of lubricating oil, thereby further improving the seizure resistance of the bearing 10. can be improved. Furthermore, as an eighth modification of the present embodiment, as shown in FIG. 13, the oil saving recess 30 may be formed larger than the recess 13d.

It should be noted that the present invention is not limited to those illustrated in the above embodiments, and can be modified as appropriate without departing from the gist of the present invention.

10 Tapered roller bearing 11 Outer ring 11a Outer ring raceway surface 12 Inner ring 12a Inner ring raceway surface 13 Tapered roller 13a Rolling surface 13b Large diameter side end surface 13c Small diameter side end surface 13d Recess 13e Annular contact surface 14 Cage 15 Large diameter side annular portion 15a axial inner end surface (pocket surface)
16 Small-diameter side annular portion 16a Axial inner end surface 17 Column portion 18 Pocket 20 Oil groove 21 End connecting side 30 Oil storage recess S1 First clearance S2 Second clearance D1 Roller axial dimension of the first clearance D2 Second clearance Dimension in roller axial direction Ra Curvature radius of large-diameter end surface of tapered roller SRy Curvature radius of pocket surface

Claims (7)

an outer ring having an outer ring raceway surface on its inner peripheral surface; an inner ring having an inner ring raceway surface on its outer peripheral surface; a plurality of tapered rollers provided to roll between the outer ring raceway surface and the inner ring raceway surface; and a retainer that retains the tapered rollers of the rollers at approximately equal intervals in the circumferential direction,
The retainer includes a large-diameter side annular portion, a small-diameter side annular portion arranged coaxially with the large-diameter side annular portion, and the large-diameter side annular portion and the small-diameter side annular portion. a plurality of pillars connected in the direction and provided at approximately equal intervals in the circumferential direction; A roller bearing,
The retainer has a first gap between the axial inner end surface of the small diameter side annular portion and the small diameter side end surface of the tapered roller, and the axial inner end surface of the large diameter side annular portion and the tapered roller. having a second gap between the large-diameter side end surface of the roller,
The dimensions of the first gap and the second gap are each set to 0.3 mm or less,
At least one oil groove for storing lubricating oil is provided on the axially inner end surface of the large-diameter side annular portion,
The oil groove is provided so that the large-diameter end surface of the tapered roller and the axial inner end surface of the large-diameter annular portion overlap in the longitudinal direction of the tapered roller ,
The large-diameter end face of the tapered roller has a circular recess formed at the center of the large-diameter end face, and is provided around the recess to contact the axial inner end face of the large-diameter annular portion. a possible toric contact surface;
The tapered roller bearing, wherein the oil groove is provided so that the contact surface of the annular ring and the axially inner end surface of the large-diameter side annular portion overlap each other in the longitudinal direction of the tapered roller. . 2. The tapered roller bearing according to claim 1 , wherein the oil groove is formed in an annular fan shape along the circumferential direction of the large diameter side annular portion. 3. A pair of end connecting sides, which are both longitudinal sides of the oil groove, are formed in an arc shape following the outer periphery of the annular contact surface of the tapered roller. tapered roller bearings. 2. The tapered roller bearing according to claim 1 , wherein the oil groove is formed in an annular fan shape along the annular contact surface of the tapered roller. An oil storage recess for storing lubricating oil is formed at a position where the recess of the tapered roller overlaps with the recess of the tapered roller in the axial direction inner end face of the large-diameter side annular portion of the retainer. The tapered roller bearing according to claim 4 . The axial inner end surface of the large diameter side annular portion is formed in a concave spherical shape, and the large diameter side end surface of the tapered roller is formed in a convex spherical shape,
The concave spherical curvature radius SRy of the axial inner end surface of the large diameter side annular portion is set within ±10% of the convex spherical curvature radius Ra of the large diameter side end surface of the tapered roller. The tapered roller bearing according to claim 1, wherein The cone according to any one of claims 1 to 6 , wherein the lubricating oil is intermittently supplied to the inside of the bearing, or the lubricating oil inside the bearing is used in a very small amount. roller bearing.

Images