JP2010090915A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing properly maintaining lubrication between the guided face of a cage and the guiding face of a guide member while actively suppressing wear at places particularly liable to wear. <P>SOLUTION: The rolling bearing 10 comprises an outer ring 11 having a guiding face 21 to which the guided face 22 of the cage 14 is opposed in a slidably contactable manner. The outer ring 11 has an oil air flow path 17b which has an inclined portion 17b2 located more axially inside as tending to the downstream side in the distributing direction of compressed air. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rolling bearing, and more particularly to a rolling bearing of a type in which compressed air such as an oil-air lubrication method is blown between a cage and a guide surface thereof.

  In general, a rolling bearing such as a cylindrical roller bearing includes an outer ring, an inner ring disposed concentrically on the radially inner side of the outer ring, a plurality of rolling elements disposed so as to be capable of rolling between the outer ring and the inner ring, and a plurality of rolling elements. And a cage that holds the circumferential spacing of the rolling elements. In addition, as a guide method for the cage of the rolling bearing, three methods, an outer ring guide, an inner ring guide, and a rolling element guide, are known.

  Among the above guide methods, the rolling element guide is placed in the cage pocket due to the swinging of the cage due to the centrifugal force generated during high-speed rotation, increased surface pressure due to the load received from the rolling element, insufficient lubrication of the sliding surface, etc. Heat generation and image sticking are likely to occur, which is disadvantageous in terms of durability. On the other hand, outer ring guides and inner ring guides (hereinafter collectively referred to as raceway guides) have higher wear resistance at high-speed rotation than rolling element guides. It can be used suitably. However, it is desired to further improve the wear resistance performance of this raceway guide. Here, in order to reduce the wear caused by the contact between the cage and the raceway, it is required to maintain proper lubrication between them. It is effective to suppress.

In addition, Patent Document 1 below describes that lubricant and seizure due to contact between the two are prevented by supplying lubricating oil between the cage and the outer ring.
Japanese Patent Laid-Open No. 5-60145

  An object of the present invention is to provide a rolling bearing capable of appropriately maintaining lubrication between a cage and its guide surface and capable of suppressing the wear particularly at a portion where the wear is likely to occur.

The rolling bearing according to the present invention includes a first race member having an annular first raceway surface, a second race member having an annular second raceway surface facing the first raceway surface, and the second raceway surface. An annular guide surface disposed at a position shifted in the axial direction, and a guide member formed integrally with or separately from the second track member, and the first track surface and the second track surface A plurality of rolling elements disposed so as to be capable of rolling therebetween, and an annular cage having a guided surface that holds the plurality of rolling elements at a predetermined interval in the circumferential direction and opposes the guide surface in a slidable manner With
The guide member is formed with a flow path through which compressed air for supplying lubricating oil flows, and the flow path is inclined so that the downstream side in the flow direction of the compressed air is positioned on the inner side in the axial direction, It has the discharge port which discharges compressed air between the said guide surface and the said to-be-guided surface in the downstream end of a part, It is characterized by the above-mentioned.

  According to this configuration, compressed air for supplying lubricating oil, such as an oil-air lubrication method, is discharged from the discharge port toward the inner side in the axial direction of the rolling bearing by flowing through the inclined portion of the flow path. When the guided surface of the cage comes into contact with the inner edge of the guide surface in the axial direction (for example, a portion indicated by reference numeral 11c in FIG. 1), wear easily occurs locally at the contact portion. The pressure of the compressed air flowing inward in the axial direction makes it difficult for the guided surface of the cage to come into contact with the inner edge of the guide surface in the axial direction, and lubricating oil can be actively supplied to this portion. Therefore, local wear of the cage in this part can be suppressed.

  Preferably, the guide surface has a bottom surface orthogonal to the inclined portion of the flow path, and an annular groove is formed along the circumferential direction at which the discharge port opens. By forming such an annular groove, the flow path can be perforated perpendicularly to the bottom surface of the annular groove, so that processing becomes easy and manufacture of the guide member can be facilitated.

  Moreover, it is preferable that the said annular groove has a side wall surface extended in parallel with a flow path, and the side wall surface of an annular groove does not prevent the flow of the compressed air which went to the axial direction inner side by this.

  The guide member is preferably a spacer disposed adjacent to the second track member. Since the spacer is a separate body from the second race member, it is made of a material with high heat dissipation that is different from the second race member, or the volume (mass) is made larger than the second race member to improve the heat dissipation. It is also possible to do. Therefore, the temperature rise of the guide member due to contact with the cage can be suppressed, and seizure can be prevented.

  According to the present invention, it is possible to suppress the wear particularly in a portion where the wear is likely to occur while appropriately maintaining the lubrication between the cage and the guide surface.

  FIG. 1 is a cross-sectional view of a rolling bearing 10 according to an embodiment of the present invention. The rolling bearing 10 is disposed between an annular outer ring (second race member) 11, an inner ring (first race member) 12 concentrically disposed on the inner peripheral side of the outer ring 11, and the outer ring 11 and the inner ring 12. A plurality of cylindrical rollers 13 as the rolling elements and a retainer 14 for holding the cylindrical rollers 13 at a predetermined interval in the circumferential direction are provided. In the following description, axially outward (axially outer) refers to the direction from the axial center of the cylindrical roller bearing 10 toward both axial sides, and axially inward (axially inner) refers to a cylinder. A direction from the both axial sides of the roller bearing 10 toward the center in the axial direction.

  The outer ring 11 is a member formed in an annular shape using alloy steel such as bearing steel, and an outer ring raceway surface 11a on which the cylindrical roller 13 rolls is formed along the circumferential direction on the inner peripheral surface thereof. . Further, an outer ring flange portion 11b that protrudes radially inward is formed on one axial side (the left side in FIG. 1) of the outer ring raceway surface 11a. It is set as the guide surface 21 to guide. The guide surface 21 is disposed closer to the inner ring 12 than the outer ring raceway surface 11a. In addition, although this outer ring collar part 11b is arrange | positioned at intervals in the axial direction with the cylindrical roller 13, it may regulate the axial direction position of the cylindrical roller 13 by contacting with the cylindrical roller 13. .

The inner ring 12 is also a member formed in an annular shape using alloy steel such as bearing steel, and an inner ring raceway surface 12a on which the cylindrical roller 13 rolls is formed on an outer peripheral surface thereof so as to face the outer ring raceway surface 11a. Has been. Further, an inner ring flange 12b is formed on the outer peripheral portion of the inner ring 12 so as to protrude radially outward on both axial sides of the inner ring raceway surface 12a, and the axial movement of the cylindrical roller 13 is restricted by the inner ring flange 12b. Has been.
The plurality of cylindrical rollers 13 can roll on the outer ring raceway surface 11a and the inner ring raceway surface 12a, whereby the outer ring 11 and the inner ring 12 are relatively rotatable.

  An outer spacer 15 is provided adjacent to the left side of the outer ring 11 in the axial direction, and the axial position of the outer ring 11 is set by the outer spacer 15. Further, an inner spacer 16 is provided adjacent to the left side of the inner ring 12 in the axial direction, and the axial position of the inner ring 12 is set by the inner spacer 16. The outer spacer 15 has an inner diameter smaller than that of the outer ring 11, and an inner peripheral surface thereof is close to an outer peripheral surface of the inner spacer 16. The arrangement of the outer ring 11, the inner ring 12, and the spacers 15 and 16 may be reversed left and right.

  The cage 14 is a cylindrical member formed using a synthetic resin such as a phenol resin, and a plurality of pockets 14a that accommodate the plurality of cylindrical rollers 13 and hold the cylindrical rollers 13 at predetermined intervals are provided in the circumferential direction. They are provided at predetermined intervals. The cage 14 is disposed between the outer ring 11 and the inner ring 12 so as to be substantially concentric with both the wheels 11 and 12. On the outer peripheral surface of one side (left side in FIG. 1) of the cage 14 in the axial direction, a guided surface 22 that is slidably opposed to the guide surface 21 of the outer ring 11 is provided.

  When the cage 14 and the outer ring 11 are relatively rotated by the relative rotation of the outer ring 11 and the inner ring 12, the guided surface 22 of the cage 14 is in sliding contact with the guide surface 21 of the outer ring 11. As a result, the cage 14 is guided by the guide surface 21 such that its own rotation center is substantially the same as the rotation center of the outer ring 11 and the inner ring 12. Therefore, the outer ring 11 functions as a guide member for guiding the rotation of the cage 14.

  In the outer spacer 15 and the outer ring 11, flow paths 17a to 17c for supplying lubricating oil to the cylindrical roller bearing 10 are formed. The flow paths 17a to 17c are a first flow path 17a formed from the outer peripheral surface of the outer spacer 15 toward the radially inner side, a radially outer portion of the first flow path 17b, and a guide surface of the outer ring 11. The second flow path 17b formed obliquely between the second flow path 21 and the third flow formed from the radially inner end of the first flow path 17b toward the space between the inner ring 12 and the cage 14. Road 17c. The second flow path 17b includes a first portion 17b1 formed in the outer spacer 15 and a second portion 17b2 formed in the outer ring 11, and the first portion 17b1 is the first flow path 17a. An opening is formed on the inner peripheral surface and the right side surface of the outer spacer 15, and the second portion 17 b 2 is opened on the left end surface of the outer ring 11 and the inner peripheral surface (guide surface 21). Moreover, the 1st-3rd flow paths 17a-17c are formed in the circumferential direction multiple places (preferably 3 places or more).

  Lubricating oil is sent to the first to third flow paths 17a to 17c from a lubricating means (not shown). This lubrication means employs an oil-air lubrication system in which a minute amount of lubricating oil is supplied by compressed air, and the lubricating oil is provided between the retainer 14 and the inner ring 12 via the first flow path 17a to the third flow path 17c. To lubricate the space between the inner ring 12 and the cylindrical roller 13. The lubricating means supplies lubricating oil between the outer ring 11 and the cage 14 (between the guide surface 21 and the guided surface 22) from the first flow path 17a through the second flow path 17b, Lubricate between them.

  FIG. 2 is an enlarged cross-sectional view showing the main part of the cylindrical roller bearing 10 (parts of the guide surface 21 and the guided surface 22). The second flow path 17b (second portion 17b2) is disposed so as to incline toward the inner side in the axial direction of the cylindrical roller bearing 10 (right side in FIG. 2) as it goes radially inward. In other words, the second flow path 17b is inclined so as to be positioned on the inner side in the axial direction toward the downstream side in the flow direction of the compressed air.

  An annular groove 30 having a substantially V-shaped cross section having a bottom surface 30b and a side wall surface 30a is formed on the left end surface of the outer ring 11, and the side wall surface 30a of the annular groove 30 is formed in parallel to the second flow path 17b. The bottom surface 30b is formed perpendicular to the second flow path 17b. The radially outer end (upstream end) of the second portion 17b2 of the second flow path 17b opens at the bottom surface 30b of the annular groove 30.

  By providing such an annular groove 30, when forming the second portion 17 b 2 of the second flow path 17 b with respect to the outer ring 11, it is only necessary to form a hole perpendicular to the bottom surface 30 b. It can be done easily. Further, as shown in FIG. 1, the second flow path 17 b has the first portion 17 b 1 and the second portion 17 b 2 connected via the annular groove 30, so that the circumferential positions of both are shifted. Even so, they can communicate with each other. Therefore, the outer ring 11 and the outer spacer 15 can be assembled to the shaft or the like without considering the relative position in the circumferential direction. The annular groove 30 may be partially formed in the circumferential direction instead of the entire circumferential direction of the outer ring 11.

  As shown in FIG. 2, the second flow path 17b (second portion 17b2) has a radially inner end (downstream end) opened at the guide surface 21, and this opening serves as a compressed air discharge port 17b ′. ing. Since the second flow path 17b is also inclined with respect to the guide surface 21, the discharge port 17b 'has an elliptical shape that is long in the axial direction. The compressed air that flows through the second flow path 17 b and is discharged from the discharge port 17 b ′ is blown to the guided surface 22. The compressed air flows between the guide surface 21 and the guided surface 22 and supplies lubricating oil therebetween.

  The compressed air flowing through the second flow path 17b flows out from the discharge port 17b 'toward the inner side in the axial direction of the cylindrical roller bearing 10 due to the inclination of the second flow path 17b. As shown in FIG. 1, the guided surface 22 of the retainer 14 has the axially inner corner portion (the guide surface 21 of the guide surface 21) of the outer ring flange portion 11 b due to the pressure of the large amount of compressed air flowing out inward in the axial direction. It is less likely to come into contact with the axially inner end edge 11c, and local wear of the cage 14 at this portion 11c can be suppressed. In addition, since a large amount of compressed air flowing inward in the axial direction increases the amount of lubricating oil supplied, wear of the cage 14 in the portion 11c can be further suppressed, and the cylindrical roller 13 and the outer ring raceway surface can be suppressed. Lubricating oil can be positively supplied also to 11a.

  Further, since the contact surface pressure between the guide surface 21 and the guided surface 22 is lowered by discharging compressed air from the discharge port 17b ', the rotational resistance of the cage 14 can be reduced, and the guide surface 21 and the guided surface can be reduced. Abrasion and seizure associated with contact with 22 can be suppressed.

FIG. 3 is a sectional view of a rolling bearing according to the second embodiment of the present invention.
In the present embodiment, the outer ring 11 is shorter in the axial direction than the inner ring 12, and the axial position is coincident with the inner ring 12 at one axial end (the right end in FIG. 3). It is retracted in the axial direction from the inner ring 12 at the left end). The outer spacer 15 provided on the left side of the outer ring 11 has a large inner diameter at a portion 15a adjacent to the outer ring 11 in the axial direction and a small inner diameter at a portion 15b axially separated from the outer ring 11, and the portion 15b The cage 14 is disposed on the outer side in the axial direction (left side in FIG. 3), and the inner circumferential surface thereof is close to the outer circumferential surface of the inner spacer 16. Further, the inner peripheral surface 21 of the portion 15a adjacent to the outer ring 11 is arranged slightly radially inward (inner ring 12 side) with respect to the outer ring raceway surface 11a, and the guided surface 22 of the retainer 14 is opposed to be slidable. A guide surface 21 is provided.

  In the outer spacer 15, first to third flow paths 17 a to 17 c for supplying lubricating oil to the cylindrical roller bearing 10 are formed. The first flow path 17a and the third flow path 17c are the same as in the first embodiment, but the second flow path 17b is the first in that it is formed as one flow path with respect to the outer spacer 15. This is different from the embodiment.

  FIG. 4 is an enlarged cross-sectional view of a main part of the rolling bearing according to the second embodiment. In the present embodiment, an annular groove 31 having a substantially V-shaped cross section having a bottom surface 31b and a side wall surface 31a is formed in the guide surface 21 along the circumferential direction. The side wall surface 31a of the annular groove 31 is formed in parallel with the second flow path 17b, and the bottom surface 31b is formed perpendicular to the second flow path 17b. Therefore, when the second flow path 17b is formed in the outer spacer 15, it is only necessary to form a hole perpendicular to the bottom surface 31b, so that processing can be easily performed.

  The compressed air flowing through the second flow path 17b flows out from the discharge port 17b 'toward the inside in the axial direction due to the inclination of the second flow path 17b. Therefore, similarly to the first embodiment, the guided surface 22 of the retainer 14 is less likely to come into contact with the inner circumferential corner (the inner edge of the guide surface 21 in the axial direction) 15e of the outer spacer 15 on the outer ring 11 side. Thus, it is possible to suppress local wear of the cage 14 in the portion 15e. Further, since a large amount of compressed air that flows inward in the axial direction increases the amount of lubricating oil supplied, wear of the retainer 14 in the portion 15e can be further suppressed, and the cylindrical roller 13 and the outer ring raceway surface can be suppressed. Lubricating oil can be positively supplied also to 11a. In this embodiment, since the side wall surface 31a of the annular groove 31 is formed in parallel with the second flow path 17b, the side wall surface 31a does not hinder the flow of compressed air inward in the axial direction. .

  In the present embodiment, since the guide surface 21 for guiding the cage 14 is formed in the outer spacer 15 that is separate from the outer ring 11, the material of the outer spacer 15 is different from that of the outer ring 11 in terms of heat dissipation. It is also possible to increase the volume or increase the volume (mass) of the outer spacer 15 to improve heat dissipation. Thus, by increasing the heat dissipation of the outer spacer 15, it is possible to suppress the temperature increase of the outer spacer 15 due to contact with the cage 14 and to prevent the cage 14 from being seized.

  Since the guide surface 21 formed in the outer spacer 15 is disposed radially inward of the outer ring raceway surface 11a, that is, on the inner ring 12 side (inner ring raceway surface 12a side), the guide surface 21 is covered with the cage 14. The cage 14 can be guided without being made into a special shape that can be brought close to the guide surface 22 and that the guided surface 22 of the cage 14 protrudes greatly outward in the radial direction.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed in design. For example, in the first embodiment, the annular groove 31 shown in the second embodiment may be formed in the guide surface 21. In the first embodiment, the first portion 17b1 of the second flow path 17b formed in the outer spacer 15 may be formed along the axial direction without being inclined.

  In each of the above embodiments, the guided surface 22, the guide surface 21, and the second flow path 17b may be provided on both sides in the axial direction with the cylindrical roller 13 interposed therebetween. However, according to the present invention, in the cylindrical roller bearing 10 in which the guided surface 22, the guide surface 21 and the like are provided only on one side in the axial direction, the guided surface 22 of the cage 14 is the inner edge 11c in the axial direction of the guide surface 21. It is very useful in preventing contact with 15e.

  The present invention can also be applied to a rolling bearing in which the guide type of the cage is an inner ring guide. The present invention can also be applied to rolling bearings other than cylindrical roller bearings such as ball bearings, needle roller bearings, and tapered roller bearings. In the above embodiment, an oil-air lubrication system is exemplified as the lubrication means, but the present invention is not particularly limited as long as it is a lubrication system that supplies compressed oil using compressed air. Other lubrication methods such as an oil mist lubrication method for supplying a solid lubricating oil can be employed.

It is sectional drawing of the rolling bearing which concerns on the 1st Embodiment of this invention. It is an expanded sectional view of the principal part of the rolling bearing. It is sectional drawing of the rolling bearing which concerns on the 2nd Embodiment of this invention. It is an expanded sectional view of the principal part of the rolling bearing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cylindrical roller bearing 11 Outer ring 12 Inner ring 13 Cylindrical roller 14 Cage 15 Outer spacer 17b 2nd flow path 17b 'Discharge port 21 Guide surface 22 Guided surface 31 Annular groove 31a Side wall surface 31b Bottom surface

Claims (4)

A first track member having an annular first track surface;
A second track member having an annular second track surface facing the first track surface;
A guide member that has an annular guide surface disposed at a position offset in the axial direction with respect to the second track surface, and that is formed integrally with or separately from the second track member;
A plurality of rolling elements arranged to be capable of rolling between the first raceway surface and the second raceway surface;
An annular cage having a guided surface that holds the plurality of rolling elements at predetermined intervals in the circumferential direction and faces the guide surface so as to be slidable,
The guide member is formed with a flow path through which compressed air for supplying lubricating oil flows.
Compressed air is discharged between the guide surface and the guided surface at the downstream end of the portion where the flow path is inclined to the inner side in the axial direction toward the downstream side in the flow direction of the compressed air. And a discharge bearing.   2. The rolling bearing according to claim 1, wherein the guide surface has a bottom surface orthogonal to the inclined portion of the flow path, and an annular groove is formed along the circumferential direction in which the discharge port opens on the bottom surface.   The rolling bearing according to claim 2, wherein the annular groove has a side wall surface extending in parallel with an inclined portion of the flow path.   The rolling bearing according to claim 1, wherein the guide member is a spacer disposed adjacent to the second race member.

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