JP6331355B2 - Tapered roller bearing - Google Patents

Description

  The present invention relates to a tapered roller bearing.

Tapered roller bearings are characterized by a large load capacity and high rigidity compared to other rolling bearings of the same size.
FIG. 8 is an axial sectional view showing a conventional tapered roller bearing. As shown in FIG. 8, the tapered roller bearing 100 includes an inner ring 101, an outer ring 102, a plurality of tapered rollers 103 interposed between the inner and outer rings 101 and 102, and a plurality of tapered rollers 103. And an annular retainer 104 that is held at equal intervals in the direction (see, for example, Patent Document 1).

  The cage 104 includes a small-diameter annular portion 105, a large-diameter annular portion 106, and a plurality of column portions 107 that are laid between the annular portions 105 and 106. The retainer 104 constitutes a pocket 108 for accommodating the tapered roller 103 by the annular portions 105 and 106 and the adjacent column portion 107.

Japanese Patent No. 4151347

In general, a tapered roller bearing tends to have a larger rotational torque than a ball bearing or the like.
Here, the torque loss of the tapered roller bearing is mainly classified into three types, that is, a rolling viscous resistance between the bearing ring and the tapered roller, a stirring resistance of the lubricating oil flowing into the inner space of the bearing, and a sliding friction resistance. Is done.
Of these, the rolling viscous resistance between the bearing ring and the tapered roller and the stirring resistance of the lubricating oil flowing into the inner space of the bearing account for most of the torque loss, which is the main reason for the increase in rotational torque. It is the cause.
The above rolling viscosity resistance and the agitation resistance of lubricating oil depend on the amount of lubricating oil flowing into the annular bearing inner space formed between the inner and outer rings and suppress the inflow amount of lubricating oil flowing into the bearing inner space. By doing so, torque loss can be reduced.

On the other hand, supply of lubricating oil is necessary to reduce torque loss caused by sliding frictional resistance generated mainly at the sliding sliding portion between the roller end face and the flange.
For this reason, if the inflow amount of the lubricating oil is suppressed in order to reduce the torque loss due to the rolling viscous resistance and the stirring resistance of the lubricating oil, the rolling viscous resistance and the stirring resistance of the lubricating oil can be reduced, The sliding friction resistance increases conversely, and there is a possibility that torque loss cannot be reduced effectively. In addition, there is a risk of seizure due to the lack of lubricating oil.
For this reason, there has been a demand for a method capable of reducing sliding friction resistance and suppressing occurrence of seizure while limiting the amount of lubricating oil flowing into the bearing internal space.

  The present invention has been made in view of such circumstances, and while limiting the amount of lubricating oil flowing into the inner space of the bearing in order to reduce rotational torque, it reduces sliding friction resistance and suppresses seizure occurrence. It is an object of the present invention to provide a tapered roller bearing that can be used.

The present invention includes an inner ring having an inner ring raceway surface, an outer ring having an outer ring raceway surface concentrically disposed on an outer peripheral side of the inner ring and facing the inner ring raceway surface, and the inner ring raceway surface and the outer ring raceway surface. A plurality of tapered rollers interposed between the inner ring and the outer ring, and a retainer holding the plurality of tapered rollers, the retainer comprising: A small-diameter annular portion, a large-diameter annular portion opposed to the small-diameter annular portion by a predetermined distance from each other, and a plurality of column portions laid between the small-diameter annular portion and the large-diameter annular portion, In the tapered roller bearing in which a space surrounded by the matching column part and the annular part is configured as a pocket for accommodating the tapered roller, the small-diameter annular part is a small one provided on one end side in the axial direction of the inner ring. Between the flange and one axial end of the outer ring Arranged, the inner peripheral surface and the outer peripheral surface of the small-diameter annular portion can be slidably contacted with one end portion in the axial direction of the small flange portion and the outer ring raceway surface, respectively, and the inner peripheral surface of the small-diameter annular portion, between the outer peripheral surface of the small rib portion, to permit passage of the lubricating oil is formed a lubricating oil in an amount that limits the ring-shaped gap flowing into the annular space, the radially inner surface of the pillar portion, Lubrication that flows from the annular gap into the annular space by extending from the inner peripheral surface end of the small-diameter annular portion toward the base end of the large collar provided on the other axial end of the inner ring. A guide surface that guides oil to a base end portion of the large collar portion, and the column portion is in sliding contact with the outer ring raceway surface on a radially outer surface of each of the small-diameter annular portion side and the large-diameter annular portion side. Thus, a pair of sliding contact surfaces for positioning the retainer in the radial direction by the outer ring raceway surface is separated by a predetermined distance. Provided between the pair of sliding contact surfaces on the radially outer side surface of the column portion, the pockets adjacent to each other are communicated with each other by denting radially inward with respect to the pair of sliding contact surfaces. A recess for allowing the lubricating oil in the vicinity of the raceway surface to flow between adjacent pockets is provided, and the gap between the bottom surface of the recess and the raceway surface of the outer ring has a large diameter from the small-diameter annular portion side in the axial direction. It is characterized in that it is inclined with respect to the outer ring raceway surface so as to gradually spread toward the annular portion side.

According to the tapered roller bearing configured as described above, the amount of lubricating oil flowing into the annular space can be suppressed by the small-diameter annular portion, so that torque loss due to the rolling viscous resistance of the tapered roller bearing and the agitation resistance of the lubricating oil is reduced. can do.
In addition, the amount of lubricating oil flowing into the annular space is limited, and a part of the lubricating oil flowing into the annular space from the outside of the bearing through the annular clearance from the inner peripheral surface of the small-diameter annular portion to the inside of the column portion. It is transmitted to the surface. Furthermore, since the inner peripheral surface of the column portion is a guide surface that guides the lubricating oil to the base end portion of the large collar portion, the lubricating oil transmitted to the inner peripheral surface of this column portion is guided to the base end portion of the large collar portion. Can do. As a result, while the amount of lubricating oil flowing into the annular space is limited, the lubricating oil in the annular space is positively applied to the vicinity of the contact portion between the end face of the tapered rollers sliding with each other and the large collar portion. Can be supplied. As a result, while limiting the amount of lubricating oil flowing into the annular space to reduce rotational torque, it is possible to reduce the sliding frictional resistance between the end face of the tapered roller and the large collar, and to further cause seizure due to lack of lubricating oil. Can be suppressed.
Further, in the tapered roller bearing, a sliding contact surface is provided on the radially outer surface of the column portion to slide the outer ring raceway surface to position the cage in the radial direction by sliding contact with the outer ring raceway surface. Therefore, since the cage rotates while being guided by the outer ring raceway surface, it can rotate between the inner and outer rings accurately and stably, and the small-diameter annular portion that closes the annular opening also rotates accurately and stably. Can do. As a result, the annular opening can be stably blocked, and the inflow amount of the lubricating oil can be appropriately limited.
On the other hand, in the above tapered roller bearing, the effect of agitating the lubricating oil in the vicinity of the outer ring raceway surface is enhanced by the slidable contact of the cage column with the outer ring raceway surface, and the effect of the pump action is enhanced by increasing the lubricating oil flow velocity. And the action of sucking external lubricating oil into the annular space may be enhanced.
On the other hand, since the concave portion that communicates the pockets adjacent to each other by being recessed in the radial direction is provided on the radially outer surface of the column portion, the lubricating oil in the vicinity of the outer ring raceway surface is separated between the adjacent pockets. The flow rate of the lubricating oil can be suppressed from being excessively increased by weakening the stirring effect. Thereby, the effect of a pump action can be weakened and the excessive inflow of the lubricating oil to annular space can be suppressed. As a result, the amount of lubricating oil flowing into the annular space that is the internal space of the bearing can be appropriately limited.

  Further, in the tapered roller bearing, the radial inner side surface is such that a gap between the radial inner side surface and the inner ring raceway surface gradually narrows from the small-diameter annular portion toward the large-diameter annular portion in the axial direction. It is preferable that the inclined surface is inclined with respect to the inner ring raceway surface. In this case, the lubricating oil is smoothly smoothed by the inner peripheral surface of the column portion having no step along the axial direction. Can lead to the end.

  In the tapered roller bearing, a groove portion that is recessed radially outward may be formed along the axial direction on the radially inner side surface. In this case, the radially inner side of the column portion may be formed from the inner peripheral surface of the small-diameter annular portion. Lubricating oil transmitted to the side surface can be retained in the groove. Further, the lubricating oil retained in the groove portion can be guided to the base end portion of the large collar portion along the groove portion. Thereby, lubricating oil can be more reliably guided to the base end part of the large collar part.

Further, in the tapered roller bearing, a dimension of the annular gap at a bearing use temperature is larger than a gap dimension necessary for the outer ring raceway surface and the sliding contact surface to be in sliding contact at the bearing use temperature, and the clearance You may set to 3 times or less of a dimension.
The outer peripheral surface of the small collar is less accurate than the outer ring raceway surface, which is a relatively high precision finished surface, so the dimensions of the annular clearance at the bearing operating temperature are the same as the outer ring raceway surface at the bearing operating temperature. If the clearance dimension is less than or equal to the clearance required for sliding contact with the sliding contact surface, the annular clearance may be narrowed more than necessary, and a necessary inflow amount of lubricating oil may not be ensured.
Further, when the dimension of the annular gap at the bearing use temperature is greater than three times the gap dimension required for the outer ring raceway surface and the sliding contact surface to slide at the bearing use temperature, the lubricating oil flows more than necessary. There is a risk of allowing it.
By setting the dimension of the annular gap at the bearing operating temperature to be larger than the gap dimension necessary for the outer ring raceway surface and the sliding contact surface to be in sliding contact at the bearing operating temperature, and not more than three times the clearance dimension, The inflow amount of the lubricating oil can be preferably limited.

  In the tapered roller bearing described above, the side surface of the column portion facing the inside of the pocket of the column portion extends in a planar shape from the circumferential edge of the radially outer surface of the column portion toward the radially inner side. It is preferable that the planar portions that form the pockets facing each other are formed so as to be parallel to each other in a radial sectional view.
  Moreover, it is preferable that the radially inner side surface of the column portion is formed so that the circumferential width dimension gradually increases from the small-diameter annular portion toward the large-diameter annular portion.
  Further, the radially outer side surface of the column part is formed such that the circumferential width dimension gradually increases from the small-diameter annular part toward the large-diameter annular part side, and the radially inner side surface of the column part is It is preferable that the increase in the circumferential width dimension that increases when heading toward the large-diameter annular portion is larger than the radial outer surface of the column portion.

  According to the tapered roller bearing of the present invention, sliding friction resistance can be reduced and seizure occurrence can be suppressed while restricting the amount of lubricating oil flowing into the inner space of the bearing in order to reduce rotational torque.

It is an axial sectional view of a tapered roller bearing according to an embodiment of the present invention. It is a fragmentary perspective view when a holder | retainer is seen from the outer peripheral side. It is a fragmentary perspective view when a holder | retainer is seen from an inner peripheral side. It is an axial sectional view of a tapered roller bearing showing a cross section of a column part. In FIG. 4, it is a VV arrow directional cross-sectional view. It is principal part sectional drawing of the pillar part which shows the modification of a groove part. It is principal part sectional drawing of the pillar part which shows the modification of a recessed part. It is an axial sectional view showing a conventional tapered roller bearing.

Next, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is an axial sectional view of a tapered roller bearing according to an embodiment of the present invention.
The tapered roller bearing 1 includes an inner ring 2, an outer ring 3 disposed concentrically on the outer peripheral side of the inner ring 2, and a plurality of tapered rollers 4 arranged between the inner and outer rings 2 and 3.
The inner ring 2 is an annular member formed using bearing steel, machine structural steel, or the like, and an inner ring raceway surface 2a on which a plurality of tapered rollers 4 roll is formed on the outer periphery thereof.
The outer ring 3 is also an annular member formed using bearing steel, machine structural steel, or the like, similar to the inner ring 2. The inner ring faces the inner ring raceway surface 2 a and has a plurality of tapered rollers 4. Is formed on the outer ring raceway surface 3a.
The tapered roller 4 is a member formed using bearing steel or the like, and is interposed between the inner ring raceway surface 2a and the outer ring raceway surface 3a so as to roll freely.

Further, the tapered roller bearing 1 includes a cage 10 that holds a plurality of tapered rollers 4.
FIG. 2 is a partial perspective view of the cage 10 as viewed from the outer peripheral side, and FIG. 3 is a partial perspective view of the cage 10 as viewed from the inner peripheral side. 2, 3 and 1, the cage 10 is a synthetic resin member formed by injection molding or the like, and a pair of annular portions 11, 12 (small-diameter annular portions) facing each other at a predetermined interval. 11 and a large-diameter annular portion 12) and a plurality of column portions 13 installed between the annular portions 11 and 12 at predetermined intervals in the circumferential direction. A space surrounded by the pair of annular portions 11 and 12 and the two column portions 13 adjacent to each other constitutes a pocket 14 that accommodates and holds the tapered roller 4.

  The cage 10 is disposed in a bearing internal space S that is an annular space formed between the inner ring 2 and the outer ring 3. The plurality of tapered rollers 4 are accommodated in the respective pockets 14, and the plurality of tapered cones are accommodated. The rollers 4 are held so as to be arranged at substantially equal intervals in the circumferential direction.

  The cage 10 is restricted from moving in the axial direction when the annular side surfaces 11c and 12c facing the pocket 14 of both the annular portions 11 and 12 are in sliding contact with the small diameter end surface 4a and the large diameter end surface 4b of the tapered roller 4. ing. That is, the cage 10 is positioned in the axial direction by the two annular portions 11 and 12 being in sliding contact with the end faces 4 a and 4 b of the tapered rollers 4.

  The cage 10 is formed so that the radially outer surface 13a of the pillar portion 13 can be slidably contacted with the outer ring raceway surface 3a, and in the circumferential direction while the radially outer surface 13a is slidably contacted with the outer ring raceway surface 3a. Relative rotation. Thus, the cage 10 is positioned in the radial direction by the outer ring raceway surface 3a.

The small-diameter annular portion 11 of the cage 10 is an annular portion having a radial thickness dimension that is approximately the same as the radial thickness dimension of the column portion 13.
The small-diameter annular portion 11 is disposed between the small flange portion 5 provided on one axial end side of the inner ring 2 and the axial one end portion 6 of the outer ring 3, and the inner peripheral surface of the small-diameter annular portion 11. 11a and the outer peripheral surface 11b can be slidably contacted with the small flange portion 5 and the axial one end portion 6 of the outer ring 3, and the small diameter side opening is configured by the small flange portion 5 and the axial one end portion 6 of the outer ring 3. Part A1 is blocked.

The outer peripheral surface 11b of the small-diameter annular portion 11 is a tapered surface that extends as it is from the radially outer surface 13a of the column portion 13 that is in sliding contact with the outer ring raceway surface 3a.
A clearance required between the outer ring raceway surface 3a and the radially outer surface 13a of the column portion 13 for sliding contact between the outer ring raceway surface 3a and the radially outer surface 13a at the operating temperature at which the tapered roller bearing 1 is used. (Clearance) is provided, and a first annular ring that is a gap having the same dimension as the clearance between the outer peripheral surface 11b of the small-diameter annular portion 11 and the inner peripheral surface 6a of the axial one end portion 6 of the outer ring 3 is provided. A gap K1 is provided.

The inner peripheral surface 11a of the small-diameter annular portion 11 is formed in a substantially cylindrical shape. Accordingly, the inner circumferential surface 11a has a different inclination angle from the radially inner side surface 13b formed in a tapered shape like the radially outer surface 13a.
Because the inner peripheral surface 11a of the small diameter annular portion 11 and the outer peripheral surface 5a of the small flange portion 5 are in sliding contact between the inner peripheral surface 11a of the small diameter annular portion 11 and the outer peripheral surface 5a of the small flange portion 5 as well. A second annular gap K2 is provided as a necessary gap.

Thus, the small-diameter annular portion 11 closes the small-diameter side opening A <b> 1 while opening the annular gaps K <b> 1 and K <b> 2 between the small flange portion 5 and the axial one end portion 6 of the outer ring 3.
The annular gaps K1 and K2 on one end side in the axial direction formed by closing the small-diameter side opening A1 serve as inflow ports for lubricating oil for lubricating the tapered roller bearing 1 flowing into the bearing internal space S.

  When the inner and outer rings 2 and 3 rotate relative to each other, the tapered roller bearing 1 is caused by the agitation of the lubricating oil existing in the bearing inner space S due to the revolution of the tapered roller 4 and the centrifugal force acting on this lubricating oil. A pumping action is caused to cause the lubricating oil in the bearing inner space S to flow from the smaller diameter dimension of 3a toward the larger one.

The tapered roller bearing 1 of this embodiment is generally used in a state where a part or all of the tapered roller bearing 1 is immersed in lubricating oil.
Therefore, the lubricating oil flows into the bearing internal space S of the tapered roller bearing 1 from the small diameter side opening A1 side by the pump action. However, in the tapered roller bearing 1 according to the present embodiment, the small-diameter annular portion 11 closes the small-diameter side opening A1 while opening the annular gaps K1 and K2, so that the lubricating oil flowing into the bearing internal space S is annular. It is limited to the lubricating oil that passes through the gaps K1, K2.
The first annular gap K1 and the second annular gap K2 allow the passage of the lubricating oil, but restrict the amount of lubricating oil more than necessary for the lubrication of the bearing inner space S from flowing into the bearing inner space S. .
That is, the small-diameter annular portion 11 closes the small-diameter side opening A1 so as to restrict a necessary amount or more of lubricating oil from flowing into the bearing internal space S.

If the amount of lubricating oil flowing into the bearing internal space S becomes larger than necessary, the rotational torque of the tapered roller bearing 1 may increase due to the stirring resistance and rolling viscosity resistance of the lubricating oil.
In this respect, in the present embodiment, since the inflow amount of the lubricating oil flowing into the bearing internal space S is limited by the small diameter annular portion 11, the inflow amount of the lubricating oil flowing into the bearing internal space S can be suppressed, The rotational torque of the tapered roller bearing 1 can be reduced.

Here, the amount of lubricating oil necessary for the lubrication of the tapered roller bearing 1 is small, and if a slight gap is provided to allow the lubricating oil to flow into the bearing internal space S, the necessary amount of lubricating oil can be secured. it can.
Therefore, the gap dimensions of the first annular gap K1 and the second annular gap K2 are set to be as small as possible within a range that allows the lubricating oil to pass and does not affect the operation of each part.

As described above, the clearance dimension of the first annular gap K1 is set to the same dimension as the clearance required for the outer ring raceway surface 3a and the radially outer surface 13a to be in sliding contact at the operating temperature at which the tapered roller bearing 1 is used. Has been.
For example, when the size of the tapered roller bearing 1 is about 30 to 40 mm in inner diameter and 70 to 80 mm in outer diameter, the outer ring raceway surface 3 a and the radially outer surface 13 a are at the use temperature at which the tapered roller bearing 1 is used. The clearance required for sliding contact is set to at least 100 μm by comparing the diameters. If the diameter is smaller than 100 μm, the contact surface pressure between the radially outer side surface 13a of the cage 10 and the outer ring raceway surface 3a increases, and the cage 10 may not be able to smoothly come into sliding contact with the outer ring raceway surface 3a. This is because.
By setting the clearance to at least 100 μm or more, the cage 10 and the outer ring raceway surface 3a can be brought into smooth sliding contact.
Moreover, since the clearance dimension of the 1st annular clearance K1 is set to the same dimension as the said clearance as mentioned above, it is set to at least 100 micrometers similarly to the said clearance.

Assuming that the use temperature at which the tapered roller bearing 1 is used is 150 ° C., even if the clearance is set at room temperature, the use temperature depends on the difference in thermal expansion coefficient due to the different materials of the outer ring 3 and the cage 10. Below is not the target clearance.
Therefore, when the size of the bearing is the above and the material of the cage is PPS resin (Poly Phenylene Sulfide Resin), the clearance is at least 200 μm at room temperature in comparison with each diameter. Set to Thereby, when the outer ring 3 and the cage 10 are thermally expanded by setting the operating temperature to 150 ° C., the clearance can be set to at least 100 μm in comparison with each diameter.

The gap size at the use temperature of the second annular gap K2 is set to be larger than the clearance at the use temperature and the gap dimension of the first annular gap K1 and not more than three times these dimensions.
Since the outer peripheral surface 5a of the small flange portion 5 has a lower accuracy than the outer ring raceway surface 3a, which is a relatively high-precision finished surface, the dimension at the operating temperature of the second annular gap K2 is the bearing operating temperature. If the outer ring raceway surface 3a and the radially outer surface 13a are less than the clearance required for sliding contact with each other, the second annular gap K2 may be narrowed more than necessary, and a necessary amount of lubricating oil inflow cannot be ensured. There is a fear. Furthermore, the contact surface pressure between the outer ring raceway surface 3a and the radially outer side surface 13a becomes unnecessarily large, which may cause rotational resistance between the outer ring 3 and the cage 10.
Further, if the size of the second annular gap K2 at the operating temperature is larger than three times the clearance at the bearing operating temperature, there is a possibility that the inflow of lubricating oil may be permitted more than necessary.
By setting the size of the second annular gap K2 at the service temperature to be larger than the clearance at the bearing service temperature and not more than 3 times the clearance, the amount of inflow of lubricating oil can be suitably limited.

  For example, if the clearance at room temperature is set to 200 μm by comparing the diameters and the clearance at a use temperature of 150 ° C. is 100 μm, the clearance dimension of the second annular gap K2 is Is set to be larger than 100 μm and not larger than 200 μm, and under operating temperature, larger than 200 μm and not larger than 300 μm.

  In the above description, the case where the dimension at the operating temperature of the second annular gap K2 is set to three times or less of the clearance has been described, but the dimension at the operating temperature of the second annular gap K2 is equal to or less than twice the clearance. It is more preferable to set the flow rate of the lubricating oil, whereby the inflow amount of the lubricating oil can be more suitably limited.

  As described above, the gap dimensions of the first annular gap K1 and the second annular gap K2 are set to be as small as possible within a range that allows the lubricating oil to pass and does not affect the operation of each part.

  The large-diameter annular portion 12 of the cage 10 is an annular portion disposed between the large collar portion 7 provided on the other axial end side of the inner ring 2 and the other axial end portion 8 of the outer ring 3. It is.

  The large-diameter annular portion 12 has a radial thickness dimension that is smaller than the radial thickness dimension of the column portion 13. Therefore, as shown in FIGS. 2 and 3, the large-diameter annular portion 12 is configured such that the radially inner side surface 13 b and the radially outer side surface 13 a of the column portion 13 are the inner peripheral surface 12 a and the outer peripheral surface of the large-diameter annular portion 12. 12b is provided so as to form a step in the radial direction. That is, the column portion 13 has an inner peripheral side end surface 13c that connects the step between the radial inner side surface 13b of the column portion 13 and the inner peripheral surface 12a of the large-diameter annular portion 12, and It has an outer peripheral side end surface 13d connecting the steps between the radial outer surface 13a and the outer peripheral surface 12b of the large-diameter annular portion 12.

As shown in FIG. 1, the large-diameter annular portion 12 is disposed in a large-diameter side opening A <b> 2 constituted by the large collar portion 7 and the other axial end portion 8.
A relatively large gap is formed between the inner peripheral surface 12 a of the large-diameter annular portion 12 and the outer peripheral surface 7 a of the large collar portion 7.
A relatively large gap is also formed between the outer peripheral surface 12 b of the large-diameter annular portion 12 and the inner peripheral surface 8 a of the other axial end portion 8.
A gap formed between the large-diameter annular portion 12 and the inner and outer rings 2 and 3 is formed larger than the above-described annular gaps K1 and K2.

The clearance formed between the large-diameter annular portion 12 and the inner and outer rings 2 and 3 formed in the other-end-side annular opening A2 is the lubricating oil flowing into the bearing internal space S by the pump action. It becomes a discharge port.
That is, the lubricating oil that has flowed into the bearing internal space S by the pumping action is used for lubrication in the bearing internal space S and is discharged from the other end side annular opening A2.
In the present embodiment, the gap formed between the large-diameter annular portion 12 and the inner and outer rings 2 and 3 is formed larger than the above-described annular gaps K1 and K2. The lubricating oil to be discharged can be quickly discharged to the outside.

FIG. 4 is an axial sectional view of a tapered roller bearing showing a cross section of the column portion 13.
2 and 3, as described above, the column portion 13 of the cage 10 rotates relative to the circumferential direction while bringing the radially outer surface 13a into sliding contact with the outer ring raceway surface 3a. It is positioned in the radial direction by the raceway surface 3a.

The radially outer surface 13a of the column portion 13 is provided with a small diameter side sliding contact surface 15 on the axial small diameter annular portion 11 side and a large diameter side sliding contact surface 16 on the axial large diameter annular portion 12 side. Yes.
Both the small diameter side slidable contact surface 15 and the large diameter side slidable contact surface 16 are formed as curved surfaces along the outer ring raceway surface 3a, and are provided so as to be in slidable contact with the outer ring raceway surface 3a.
The small diameter side sliding contact surface 15 and the large diameter side sliding contact surface 16 are in sliding contact with the outer ring raceway surface 3a, thereby positioning the cage 10 in the radial direction by the outer ring raceway surface 3a.

As described above, the inner peripheral surface 11 a of the small-diameter annular portion 11 in the cage 10 is configured to be in sliding contact with the outer peripheral surface 5 a of the small collar portion 5 of the inner ring 2. The inner peripheral surface 11a of the small-diameter annular portion 11 is formed in a cylindrical shape parallel to the axial direction, and is in sliding contact with the cylindrical outer peripheral surface 5a.
On the other hand, the small diameter side sliding contact surface 15 and the large diameter side sliding contact surface 16 are in sliding contact with the outer ring raceway surface 3a which is a tapered surface.
Thus, the cage 10 is in sliding contact with the inner peripheral surface 11a on the inner ring 2 side and the outer ring raceway surface 3a on the outer ring 3 side, which are formed so as to have different inclination angles. With this configuration, the cage 10 can be more reliably positioned in the radial direction.

Between the small-diameter side slidable contact surface 15 and the large-diameter side slidable contact surface 16, a recess 17 is formed that is recessed in the radial direction with respect to the small-diameter side slidable contact surface 15 and the large-diameter side slidable contact surface 16. Yes. The concave portion 17 is formed in each column portion 13.
The concave portion 17 is provided so as to be positioned substantially at the center of the axial outer ring raceway surface 3a.
The small diameter side slidable contact surface 15 and the large diameter side slidable contact surface 16 are provided on both sides in the axial direction of the recess 17.
Thereby, the small diameter side slidable contact surface 15 and the large diameter side slidable contact surface 16 can be slidably contacted with the end portion on the small diameter side in the axial direction and the end portion on the large diameter side of the outer ring raceway surface 3a, respectively. As a result, even if the concave portion 17 is provided on the radially outer surface 13a of the column portion 13, the small-diameter side sliding contact surface 15 and the large-diameter side sliding contact surface are suppressed while suppressing the cage 10 from being inclined with respect to the axial direction. 16 can be brought into sliding contact with the outer ring raceway surface 3a in a stable state.

  Moreover, the recessed part 17 is recessed over the circumferential direction whole region of the pillar part 13, and connects the pockets 14 adjacent to each other.

Here, in the tapered roller bearing 1 of the present embodiment, the amount of lubricating oil flowing into the bearing internal space S can be suppressed by the small-diameter annular portion 11 of the cage 10, so that torque loss can be reduced. .
Further, the cage 10 of the tapered roller bearing 1 is positioned in the radial direction by sliding the column portion 13 against the outer ring raceway surface 3a, and is guided and rotated by the outer ring raceway surface 3a. The small-diameter annular portion 11 that closes the small-diameter side opening A1 can also rotate with high accuracy and stability. As a result, the small diameter side opening A1 can be stably blocked, and the inflow amount of the lubricating oil can be appropriately limited.
On the other hand, in the tapered roller bearing 1, the pillar portion 13 of the cage 10 is in sliding contact with the outer ring raceway surface 3a, so that the effect of stirring the lubricating oil in the vicinity of the outer ring raceway surface 3a is increased, and the flow velocity of the lubricating oil is increased. As a result, the effect of the pumping action is enhanced, and the action of sucking external lubricating oil into the bearing inner space S may be enhanced.

In this respect, according to the tapered roller bearing 1 of the present embodiment, the concave portion 17 that communicates the pockets 14 adjacent to each other by being recessed in the radial direction is provided on the radial outer surface 13a of the cage 10. The lubricating oil in the vicinity of the outer ring raceway surface 3a can be caused to flow between the adjacent pockets 14, and the stirring effect can be weakened to prevent an excessive increase in the flow speed of the lubricating oil. Thereby, the effect of a pump action can be weakened and the excessive inflow of the lubricating oil to the bearing internal space S can be suppressed. As a result, the amount of lubricating oil flowing into the bearing internal space S can be appropriately limited.
Thereby, according to the tapered roller bearing 1 of this embodiment, torque loss can be reduced by appropriately suppressing the inflow amount of the lubricating oil flowing into the bearing internal space S.

The bottom surface 17 a of the concave portion 17 is formed in an arc whose center when viewed from the axial direction is centered on the axial center of the tapered roller bearing 1.
Further, the clearance T (FIG. 4) between the bottom surface 17a of the recess 17 and the outer ring raceway surface 3a is such that the outer ring raceway surface 3a and the two sliding contact surfaces 15, 16 are at the operating temperature at which the tapered roller bearing 1 is used. It is set to at least 10 times the gap (the above-mentioned clearance) necessary for sliding contact.
For example, as described above, if the clearance at a use temperature of 150 ° C. is set to 100 μm, the gap T is set to at least 1 mm.

  When the clearance T is smaller than 10 times the clearance under the operating temperature of the tapered roller bearing 1, it becomes difficult to sufficiently flow the lubricating oil in the vicinity of the outer ring raceway surface 3a between the pockets 14 adjacent to each other. The effect of weakening the action is reduced. Therefore, the pump action can be effectively weakened by setting the gap T to be at least 10 times the clearance at the operating temperature.

  In addition, the larger the gap T, the more the amount of lubricating oil that passes through the recess 17 can be increased, and the effect of the pump action can be further weakened. However, if the interval T is too large, the thickness of the column portion 13 in the radial direction is reduced, so that the strength of the column portion 13 may be reduced. For this reason, the gap T is set within a range in which the strength required for the pillar portion 13 can be ensured.

Further, since the peripheral portion of the column portion 13 has a higher peripheral speed, the stirring effect on the lubricating oil is high, and the portion on the large diameter side has a greater contribution to the pump action. On the other hand, as described above, if the amount of lubricating oil passing through the recess 17 is further increased, the effect of the pump action can be further reduced.
Therefore, the bottom surface 17a of the recess 17 in the present embodiment is formed so as to be inclined linearly with respect to the outer ring raceway surface 3a so that the gap T gradually widens from the small-diameter annular portion 11 in the axial direction toward the large-diameter annular portion 12. Has been.

As a result, the gap T is widened toward the large diameter side where the stirring effect is high compared to the small diameter side, so the large diameter annular portion 12 side that is a part where the stirring effect is higher and the contribution to the pump action is large. It is possible to increase the amount of lubricating oil that passes through the closer portion. Thereby, it is possible to effectively weaken the pump action in a balanced manner from the small diameter side to the large diameter side.
Moreover, since the radial direction depth of the recessed part 17 can be made shallow in the part by the side of the small diameter in which the contribution to a pump action is comparatively few in the pillar part 13, the thickness of the radial direction of the pillar part 13 is reduced greatly. There is no need. That is, in this case, since the concave portion 17 is formed so that only a necessary portion has a deep radial depth, it is advantageous in securing a necessary strength as the column portion 13.

The axial length L (FIG. 4) of the recess 17 is set in a range of 40% or more and 70% or less with respect to the axial length of the outer ring raceway surface 3a.
When the axial length L of the concave portion 17 is made smaller than 40% of the axial length of the outer ring raceway surface 3a, the effect of weakening the pump action is remarkably reduced. When the axial length L of the concave portion 17 is larger than 70% of the axial length of the outer ring raceway surface 3a, it is difficult to secure a necessary area as both sliding contact surfaces 15, 16 on the radially outer surface 13a. . By setting the axial length L of the concave portion 17 in the range of 40% or more and 70% or less with respect to the axial length of the outer ring raceway surface 3a, both sliding contact surfaces 15 are effectively weakened while the pump action is effectively weakened. , 16 can secure the necessary area.

5 is a cross-sectional view taken along line VV in FIG.
As shown in FIG. 5, the pillar side surface 13e facing the inside of the pocket 14 of the pillar part 13 is a planar part extending in a planar shape from the circumferential edge 13a1 of the radially outer surface 13a toward the radially inner side. 20 and a curved surface portion 21 connected from the radially inner end portion of the planar portion 20 and extending further radially inward.

The radially inner end of the planar portion 20 is located on the inner diameter side of the pitch circle of the tapered roller 4.
The planar portion 20 is mutually aligned along the axial direction with respect to a straight line P connecting the axial center of the tapered roller 4 and the axial center of the tapered roller bearing 1 accommodated in the pocket 14 facing the planar portion 20. It is formed on a parallel plane. Accordingly, the planar portions 20 that form the pockets 14 facing each other are formed in parallel to each other along the axial direction. The interval in the circumferential direction between the planar portions 20 facing each other is slightly larger than the outer diameter of the tapered roller 4, and is slightly between the rolling surface 4 c and the planar portion 20. A gap is provided.
Thus, the retainability of the tapered roller 4 can be improved by forming the planar portions 20 that form the pockets 14 facing each other in parallel with each other along the axial direction.

The curved surface portion 21 is formed in a curved surface shape along the rolling surface of the tapered roller 4, from the radially inner end portion of the planar portion 20 to the circumferential edge 13 b 1 of the radially inner side surface 13 b of the column portion 13. It extends.
Since the curved surface portion 21 is formed in a curved surface shape along the rolling surface of the tapered roller 4, the circumferential width dimension of the curved surface portion 21 of the column portion 13 gradually increases inward in the radial direction, The circumferential width dimension of the radially inner side surface 13 b is formed wider than the circumferential width dimension of the planar portion 20 of the column portion 13.

As shown in FIG. 3, the radially inner side surface 13 b of the column portion 13 is formed so that its circumferential width dimension gradually increases from the small-diameter annular portion 11 toward the large-diameter annular portion 12. Similarly, the radially outer side surface 13a of the column portion 13 is formed so that its circumferential width dimension gradually increases from the small-diameter annular portion 11 toward the large-diameter annular portion 12 side.
The radially inner side surface 13b is formed such that the amount of increase in the circumferential width dimension that increases when going to the large-diameter annular portion 12 side is larger than that of the radially outer surface 13a.

4 and 5, the radially inner side surface 13 b of the column portion 13 extends from the axially inner end edge 11 a 1 (inner peripheral surface end portion) of the inner peripheral surface 11 a of the small-diameter annular portion 11 to the inner peripheral side end surface. It extends linearly over the inner peripheral side edge 13c1 of 13c. The inner peripheral side edge 13 c 1 of the column part 13 extends to the vicinity of the base end part 7 b of the large collar part 7. For this reason, the radially inner side surface 13 b extends from the axially inner end edge 11 a 1 of the small diameter annular portion 11 toward the proximal end portion 7 b of the large collar portion 7.
More specifically, the radially inner side surface 13b of the column portion 13 is inclined so as to increase in diameter from the small-diameter annular portion 11 in the axial direction toward the large-diameter annular portion 12 side.
Further, the inner ring raceway surface 2b is formed so that the gap between the inner radial surface 13b and the inner ring raceway surface 2a gradually narrows from the small-diameter annular portion 11 toward the large-diameter annular portion 12 side. It is set as the inclined surface inclined with respect to.

As described above, between the inner peripheral surface 11 a of the small-diameter annular portion 11 and the outer peripheral surface 5 a of the small flange portion 5, more lubricating oil than the amount necessary for lubricating the tapered roller bearing 1 is present in the bearing internal space S. A second annular gap K2 that restricts inflow is provided.
Therefore, after the amount of the lubricating oil flowing into the bearing internal space S is limited, a part of the lubricating oil flowing into the bearing internal space S from the second annular gap K2 by the pumping action is the inner peripheral surface of the small diameter annular portion 11. It is transmitted from 11 a to the radially inner side surface 13 b of the column portion 13.

The radially inner side surface 13b of the column part 13 is inclined so as to increase in diameter from the axially small diameter annular part 11 toward the large diameter annular part 12 side. For this reason, when the lubricating oil is transmitted to the radial inner side surface 13b, the lubricating oil further moves along the radial inner side surface 13b by the action of the centrifugal force generated by the rotation of the cage 10. Since the radially inner side surface 13b extends from the axially inner end edge 11a1 of the small-diameter annular portion 11 toward the base end portion 7b of the large collar portion 7, the lubricating oil moving along the radially inner side surface 13b is The base end portion 7 b of the large collar portion 7 is guided.
As described above, the radially inner side surface 13b constitutes a guide surface that guides the lubricating oil flowing into the bearing inner space S from the second annular gap K2 to the base end portion 7b of the large collar portion 7.

  For this reason, the lubricating oil which flows in from the second annular gap K2 and is transmitted to the radially inner side surface 13b can be guided to the base end portion 7b of the large collar portion 7. As a result, the amount of lubricating oil flowing into the bearing internal space S is limited, but the vicinity of the contact portion between the end surface 4b of the tapered roller 4 that slides and slides on the large collar portion 7 is within the bearing internal space S. Can be actively supplied. As a result, the sliding frictional resistance between the end surface 4b of the tapered roller 4 and the large collar portion 7 can be reduced while the amount of lubricating oil flowing into the bearing internal space S is limited to reduce the rotational torque, and the lack of lubricating oil It is possible to suppress the occurrence of image sticking.

  That is, according to the present embodiment, by limiting the amount of lubricating oil flowing into the bearing internal space S, the rolling viscous resistance and the stirring of the lubricating oil that depend on the amount of lubricating oil flowing into the bearing internal space S are reduced. Reduces sliding friction resistance by guiding and actively supplying lubricating oil that has flowed into the bearing internal space S to sliding sliding parts that require lubricating oil while reducing rotational torque by suppressing resistance And the occurrence of burn-in can be suppressed.

Further, as described above, the column portion side surface 13e of the column portion 13 is constituted by the planar portion 20 and the curved portion 21, so that the circumferential width dimension of the radially inner side surface 13b is the planar shape of the column portion 13. It is formed wider than the circumferential width of the portion 20. For this reason, the area of the radial inner side surface 13b is larger than, for example, a case where the pillar side surface 13e is formed in a linear shape along the radial direction.
For this reason, the amount of lubricating oil that can be transmitted through the radially inner side surface 13b can be increased, and the amount of lubricating oil that can be guided can be increased.

Further, as shown in FIGS. 4 and 5, the radially inner side surface 13 b is formed with a groove portion 25 that is recessed radially outward at substantially the center in the circumferential direction. The groove portion 25 is formed in each column portion 13. The groove 25 is recessed in a semicircular shape, and is formed over the entire axial direction of the radially inner side surface 13b along the axial direction.
By forming the groove portion 25 on the radially inner side surface 13b, the lubricating oil flowing from the second annular gap K2 and transmitted to the radially inner side surface 13b can be retained in the groove portion 25.
Furthermore, the lubricating oil retained in the groove portion 25 can be guided to the base end portion 7 b of the large collar portion 7 along the groove portion 25. Thereby, lubricating oil can be more reliably guided to the base end part 7b of the large collar part 7. FIG.

  Further, in the present embodiment, the radially inner side surface 13b is such that the gap between the radially inner side surface 13b and the inner ring raceway surface 2a gradually narrows from the axially small diameter annular portion 11 toward the large diameter annular portion 12 side. Since the inner ring raceway surface 2a is inclined with respect to the inner ring raceway surface 2a, the lubricating oil is smoothly supplied to the base end portion 7b of the large collar portion 7 by the radial inner side surface 13b of the column portion 13 having no step along the axial direction. Can lead.

  In addition, this invention is not limited to the said embodiment. In the above embodiment, the bottom surface 17a of the concave portion 17 provided on the radially outer surface 13a is formed with respect to the outer ring raceway surface 3a so that the gap T gradually widens from the axially small diameter annular portion 11 toward the large diameter annular portion 12. Although the case where it is formed to be inclined in a straight line is shown, if the lubricating oil can be properly passed and the pump action can be suppressed, the bottom surface 17a is formed so as to be parallel to the radially outer surface 13a. Alternatively, the bottom surface 17a may be formed in a curved shape such as a circle.

Moreover, in the said embodiment, although the shape when the bottom face 17a of the recessed part 17 was seen from the axial direction was formed in the circular arc centering on the axial center of the tapered roller bearing 1, it showed to Fig.6 (a). As described above, the shape of the bottom surface 17a when viewed from the axial direction is an arc having a smaller radius, so that the gap with the outer raceway surface 3a is widened from the center in the circumferential direction of the bottom surface 17a toward the planar portion 20. It may be. In this case, the lubricating oil can be smoothly guided and passed through the gap between the recess 17 and the outer ring raceway surface 3a.
Further, as shown in FIG. 6B, the shape of the bottom surface 17a when viewed from the axial direction may be triangular. Also in this case, as in FIG. 6A, the lubricating oil can be smoothly guided and passed through the gap between the recess 17 and the outer ring raceway surface 3a.

  Moreover, in the said embodiment, although the case where the recessed part 17 of the radial direction outer side surface 13a was provided in all the column parts 13 does not need to provide in all the column parts 13, it is the inside of the column parts 13 arranged in the circumferential direction. It can be changed as appropriate, for example, by providing recesses 17 every other one.

  Moreover, in the said embodiment, although the case where the groove part 25 provided in the radial direction inner side surface 13b was formed as a groove | channel recessed in a semicircle shape was shown, if lubricating oil can be stopped in the inside, FIG. As shown in a) and (b), it may be formed in a rectangular shape, a triangular shape, or the like, and as shown in FIG. 7C, it extends over almost the entire radial direction of the radial inner side surface 13b. You may form the groove part 25 by providing a dent. In this case, the lubricating oil can be retained over almost the entire radial direction of the radially inner side surface 13 b, and more lubricating oil can be collected and guided to the base end portion 7 b of the large collar portion 7.

DESCRIPTION OF SYMBOLS 1 Tapered roller bearing 2 Inner ring 2a Inner ring raceway surface 3 Outer ring 3a Outer ring raceway surface 4 Tapered roller 5 Small flange part 5a Outer peripheral surface 6 One axial end part 7 Large collar part 7b Base end part 10 Cage 11 Small diameter annular part 11a Inner peripheral surface 11a1 Axial inner edge (end of inner peripheral surface) 12 Large-diameter annular portion 13 Column portion 13a Radial outer surface 13b Radial inner surface 14 Pocket 15 Small-diameter side sliding surface 16 Large-diameter side sliding surface 17 Recessed portion 17a Bottom surface 25 Groove A1 Small-diameter side opening K2 Second annular gap

Claims (6)

An inner ring having an inner ring raceway surface;
An outer ring having an outer ring raceway surface concentrically disposed on an outer peripheral side of the inner ring and facing the inner ring raceway surface;
A plurality of tapered rollers interposed between the inner ring raceway surface and the outer ring raceway surface so as to roll freely;
A cage disposed in an annular space between the inner ring and the outer ring, and holding the plurality of tapered rollers,
The cage includes a small-diameter annular portion, a large-diameter annular portion opposed to the small-diameter annular portion by a predetermined distance, and a plurality of column portions erected between the small-diameter annular portion and the large-diameter annular portion. In a tapered roller bearing configured to have a space surrounded by adjacent column portions and the annular portion as a pocket for accommodating the tapered rollers,
The small-diameter annular portion is disposed between a small flange provided on one end side in the axial direction of the inner ring and one axial end portion of the outer ring, and an inner peripheral surface and an outer peripheral surface of the small-diameter annular portion are respectively It is slidably contactable with the small flange portion and one axial end portion of the outer ring raceway surface, and allows passage of lubricating oil between the inner peripheral surface of the small diameter annular portion and the outer peripheral surface of the small flange portion. wherein the amount of the lubricating oil to form a ring-shaped gap that limits flowing into the annular space Suruga,
A radially inner side surface of the column portion extends from an inner peripheral surface end portion of the small-diameter annular portion toward a proximal end portion of a large collar portion provided on the other axial end side of the inner ring, It is a guide surface that guides the lubricating oil flowing into the annular space from the annular gap to the base end portion of the large collar portion,
A pair of the pillar portions slidably contact the outer ring raceway surface on the radially outer side surfaces of the small-diameter annular portion side and the large-diameter annular portion side, respectively, thereby positioning the cage in the radial direction by the outer ring raceway surface. The sliding contact surface is provided with a predetermined separation,
Between the pair of sliding contact surfaces on the radially outer side surface of the column portion, the pockets adjacent to each other are communicated with each other by denting radially inward with respect to the pair of sliding contact surfaces. A recess for allowing the lubricant to flow between adjacent pockets,
The gap between the bottom surface of the recess and the outer ring raceway surface is inclined with respect to the outer ring raceway surface so as to gradually expand from the axial small-diameter annular portion side toward the large-diameter annular portion side. Tapered roller bearing.   The radially inner side surface is spaced from the inner ring raceway surface so that a gap between the radially inner side surface and the inner ring raceway surface gradually narrows from the small-diameter annular portion toward the large-diameter annular portion in the axial direction. The tapered roller bearing according to claim 1, wherein the tapered roller bearing is inclined.   The tapered roller bearing according to claim 1 or 2, wherein a groove portion recessed radially outward is formed along the axial direction on the radially inner side surface. The column portion side surface facing the inside of the pocket of the column portion includes a planar portion extending in a planar shape from the circumferential edge of the radially outer side surface of the column portion toward the radially inner side,
The tapered roller bearing according to any one of claims 1 to 3, wherein the planar portions that are opposed to each other and form the pockets are formed so as to be parallel to each other in a radial sectional view. 5. The radially inner side surface of the column part is formed such that a circumferential width dimension thereof gradually increases from the small-diameter annular part toward the large-diameter annular part side. Tapered roller bearings described in 1. The radially outer surface of the column part is formed such that its circumferential width dimension gradually increases from the small-diameter annular part toward the large-diameter annular part side,
The radially inner side surface of the column part is formed such that the amount of increase in the circumferential width dimension that increases when going to the large-diameter annular part side is larger than the radially outer surface of the column part. The tapered roller bearing according to Item 5.

Images