JP2012021613A - Sealed bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealed bearing device which stirs grease and can re-supply grease into a bearing while suppressing an increase in manufacturing costs and deterioration in assembling properties.SOLUTION: In the sealed bearing device 100A, a rotational slinger 35 having a stirring part 35b that rotates with a rotating ring 2 to stir grease is secured to the rotating ring 2 within a bearing space T that is formed by the opposition of the rotating ring 2 to the fixed ring 3.

Description

  The present invention relates to a sealed bearing device, and more particularly to a sealed bearing device used in grease lubrication.

  Conventionally, a sealed bearing device having a tapered roller bearing or the like is used for a railway vehicle axle. As an example, in the sealed bearing device 100 shown in FIG. 6, the tapered roller bearing 1 is fitted with two inner rings 2 in a state where the back surfaces are in contact with an annular spacer 15. A single outer ring 3 facing the outer diameter side is fitted in a housing (not shown). In this case, an inner ring raceway surface 2 s that is inclined so as to expand in the direction away from the spacer 15 side is formed on the outer circumferential surface of each inner ring 2. The two outer ring raceway surfaces 3 s are formed opposite to the inner ring raceway surface 2 s of each inner ring 2.

  On both sides of the two inner rings 2 having such a configuration, annular oil drills 17 and 19 (also called annular fixing members) for restricting the movement of the inner ring 2 in the axial direction are fitted to the railcar axle 13 respectively. A predetermined preload is applied to the tapered roller bearing 1 by applying a pressing body 21 to an oil drill 17 on one side (left side in FIG. 1) in the axial direction and tightening with a bolt 23. Can do. In this state, when the railway vehicle axle 13 is rotated, the inner and outer rings 2 and 3 are rotated between the raceway surfaces 2s and 3s of the inner and outer rings 2 and 3 while the inner and outer rings 2 and 3 are relatively rotated around the rotation center axis Q (while the bearing is rotating). The plurality of rollers 5 incorporated together with the cage 11 roll along the raceway surfaces 2 s and 3 s while being held and guided by the guide surfaces 7 s and 9 s of the small collar portion 7 and the large collar portion 9.

  Further, in order to maintain a constant lubrication performance during rotation of the bearing, grease is sealed inside the bearing. In this case, in order to prevent leakage of grease to the outside of the bearing and to prevent foreign matter (for example, water, dust) from entering the inside of the bearing, the inside of the bearing is disposed on both sides of the inner and outer rings 2 and 3. A sealing mechanism 24 is provided for sealing from. Since the sealing mechanisms 24 provided on both sides of the inner and outer rings 2 and 3 have the same configuration, refer to the drawings for the sealing mechanism 24 on one axial side (right side in the figure). To explain. Hereinafter, a bearing provided with a sealing mechanism is referred to as a sealed bearing device.

  As shown in FIG. 7, in the sealing mechanism 24 of the sealed bearing device 100, the cylindrical base portion 25e is fixed to the end inner peripheral surface 3t of the outer ring 3, and the tip end portion 25t is positioned in a non-contact state with the oil drain 19. An annular seal case 25 and a seal portion 27 interposed between the seal case 25 and the oil drain 19 are provided.

  In such a sealing mechanism 24, the seal case 25 extends from the cylindrical base portion 25e to the outside in the axial direction (direction parallel to the rotation center axis Q) while bending inward in the radial direction of the bearing (direction perpendicular to the rotation center axis Q). The tip portion 25t forms a labyrinth seal with the oil drill 19.

  The seal portion 27 is fixed to the inner side surface 25 s (side surface facing the oil drill 19) of the seal case 25 and extends in the radial direction, and is fixed to the inside of the fixed slinger 29 and oil. An annular cored bar 31 extending in the direction of the cut 19 and an annular elastic body 33 attached to the extended end of the cored bar 31 are provided. An annular pressing ring (not shown) is stretched over a part of the elastic body 33, and the elastic body 33 is brought into sliding contact with the oil drain 19 by the elastic squeezing force of the pressing ring. Further, the extended end of the fixed slinger 29 is positioned in a non-contact state with respect to the oil drill 19, and a labyrinth seal is formed between the extended end of the fixed slinger 29 and the oil drill 19. Yes.

  According to such a sealing mechanism 24, the sealing performance inside the bearing is improved, and the lubrication performance during the rotation of the bearing is kept constant. At this time, the plurality of rollers 5 incorporated together with the retainer 11 between the inner and outer rings 2 and 3 are rotatably held by the retainer 11 while being held between the retainer 11 and the raceway surfaces 2s and 3s by grease. It rolls along the raceway surfaces 2s and 3s while reducing the frictional resistance.

  Further, the grease sealed in the tapered roller bearing 1 is discharged from the inside of the bearing to the seal case 25 side by the centrifugal force and the pumping action during the rotation of the bearing (during the relative rotation of the inner and outer rings 2 and 3). In the seal space portion S covered with the seal case 25, it adheres to the inner side (bearing side) of the fixed slinger 29.

  The adhered grease does not return to the inside of the bearing again unless strong vibration is applied from the outside. For this reason, only a small portion of the grease is used for lubricating the bearing, and even when these greases are consumed and the bearing has reached the end of its life, the grease discharged into the seal space S is new. It remains attached to the inside of the fixed slinger 29 in the same manner. Therefore, in order to further extend the bearing life, it is necessary to reuse the grease discharged to the seal space S during the rotation of the bearing.

  In the sealed bearing device 200 of Patent Document 1, as shown in FIG. 8, an annular spacer 234 is sandwiched between an inner ring 202 and an oil drain 219, and a bent portion 234 a provided in the annular spacer 234 and a seal case 225 are disposed. A labyrinth gap is formed between the two. As a result, the annular spacer 234 rotates together with the inner ring 202, and grease that leaks from the inside of the bearing through the labyrinth gap to the outside is recirculated to the inside of the bearing.

  Further, in this sealed bearing device 200, the outer end surface 202a of the inner ring 202 is provided with a convex portion 202b that partially projects outward in the axial direction, and the inner peripheral side end portion of the annular spacer 234 is supported on the outer peripheral surface 202c of the convex portion 202b. Let Further, the oil drill 219 is provided with a concave portion 219b that accommodates the convex portion 202b on the surface 219a facing the outer end surface 202a, and the inner ring 202 and the oil drill 219 are positioned relative to each other.

JP 2005-325867 A

  However, in the sealed bearing device 200 described in Patent Document 1, it is necessary to perform special processing on the inner ring 202 and the oil drain 219 for assembly as described above, which may increase production costs. Moreover, since it is necessary to assemble the processed inner ring 202 and the oil drill 219 via the annular spacer 234, the assembling work is complicated and it is difficult to improve the assembling accuracy.

  The present invention has been made in view of such problems, and it is an object of the present invention to provide a sealed bearing device capable of stirring grease and re-supplying grease into the bearing while suppressing an increase in production cost and deterioration in assemblability. .

The above object is achieved by the following configuration.
(1) a bearing including a rolling element that is rotatably disposed between a rotating wheel and a fixed wheel;
An annular fixing member for restricting movement of the rotating wheel in the axial direction from at least one axial side of the rotating wheel;
A sealing mechanism having a seal case attached to at least one axial direction of the fixed ring, and a seal portion that seals between the annular fixing member and the seal case;
A sealed bearing device used for grease lubrication by sealing the inside of the bearing,
A rotating slinger having a stirring unit that rotates together with the rotating wheel and stirs grease is fixed to the rotating wheel in a bearing space formed by the rotating wheel and the fixed wheel facing each other. Sealed bearing device.
(2) The rotating slinger includes a cylindrical fixing portion, and the stirring portion extending from the end on the at least one axial direction side of the cylindrical fixing portion to the outer diameter side,
The sealed bearing device according to (1), wherein the cylindrical fixing portion is fitted to an outer peripheral surface of the flange portion.
(3) The seal portion includes a metal core attached to the seal case side, and an elastic body that constitutes a seal lip that is attached to the metal core and slidably contacts the annular fixing member or a portion fixed to the annular fixing member. And a fixed slinger constituting a labyrinth seal and a portion fixed to the annular fixing member or the annular fixing member on the inner side in the axial direction from the seal lip. The sealed bearing device according to 1) or (2).
(4) The sealed bearing device according to any one of (1) to (3), wherein the stirring unit includes a plurality of slits in a circumferential direction, and the plurality of slits extend radially.
(5) The sealed bearing device according to any one of (1) to (3), wherein the agitating portion is provided with a plurality of concave grooves having a concave outer peripheral surface in the circumferential direction.

  According to the sealed bearing device of the present invention, by having the agitating portion that rotates together with the rotating wheel, the grease discharged to the seal space as the bearing rotates is agitated to prevent the grease from accumulating inside the seal case. be able to. As a result, grease can be resupplied into the bearing, and the bearing life can be extended. Moreover, since it is not necessary to change the structure of the conventional inner ring and the annular fixing member significantly, the production cost can be suppressed. Further, there is no member interposed between the inner ring and the annular fixing member, and the rotating slinger is fixed to the rotating ring in the bearing space, so that the assembling accuracy can be improved.

It is a fragmentary sectional view of the sealed bearing device concerning one embodiment of the present invention. It is a perspective view of a rotation slinger. It is a fragmentary sectional view of the sealed bearing device provided with the rotation slinger concerning the 1st modification. (A) is a perspective view of the rotation slinger which concerns on a 2nd modification, (b) is a perspective view of the rotation slinger which concerns on a 3rd modification. It is a fragmentary sectional view of the sealed bearing apparatus provided with the rotation slinger which concerns on a 4th modification. It is a fragmentary sectional view of the conventional support structure of a railway vehicle axle. It is a fragmentary sectional view of the sealed bearing apparatus used for FIG. 2 is a partial cross-sectional view of a sealed bearing device described in Patent Document 1. FIG.

  Hereinafter, embodiments of a sealed bearing device of the present invention will be described with reference to the drawings. The sealed bearing device of the present embodiment is an improvement of the sealed bearing device shown in FIGS. 6 and 7, and the same or equivalent parts in FIG. Or omitted.

  FIG. 1 is a partial cross-sectional view of a sealed bearing device 100A according to an embodiment of the present invention. The sealing mechanism 24 </ b> A according to the present embodiment includes a seal case 25 and a seal portion 27 interposed between the seal case 25 and the annular fixing member 19.

  The seal case 25 extends in the axial direction concentrically with the rotation center axis Q and is fitted to the inner peripheral surface 3t of the end portion of the outer ring 3, and the inner diameter of the bearing from the axially outer end portion of the cylindrical base portion 25e. An annular first radial extension portion 25a extending to the side, an annular axial extension portion 25b folded back from the first radial extension portion 25a and extending outward in the axial direction, and the axial extension portion 25b An annular second radial extension portion 25c that is folded back and extends to the inner diameter side, and an annular distal end portion 25t that is folded back from the second radial extension portion 25c and extends outward in the axial direction are continuous. Configured.

  In addition, the seal portion 27 has a cross-section substantially extending from the outer diameter side cylindrical portion 29a fixed to the inner side surface 25s of the axial extension portion 25b (side surface facing the annular fixing member 19) to the inner diameter side. An L-shaped fixed slinger 29 and a space formed by the fixed slinger 29 and the second radial extension portion 25c of the seal case 25 in the direction of the annular fixing member 19 are fixed to the inner peripheral surface of the fixed slinger 29. An extended annular core 31 and an annular rubber elastic body 33 attached to the extended end of the core 31 are provided. An annular presser ring (not shown) is stretched over a part of the elastic body 33, and the tip of the elastic body 33 is placed on the outer peripheral surface of the annular fixing member 19 by the elastic squeezing force of the presser ring. Make sliding contact. Thereby, the front-end | tip part of the elastic body 33 comprises the seal lip. Further, the extending end of the blocking plate portion 29b of the fixed slinger 29 is positioned in a non-contact state with respect to the annular fixing member 19 on the inner side in the axial direction from the seal lip, and the extending portion of the blocking plate portion 29b of the fixed slinger 29 extends. A labyrinth seal (narrow gap) is formed between the protruding end and the annular fixing member 19. Further, a labyrinth seal is also formed between the front end portion 25 t of the seal case 25 and the annular fixing member 19.

  Thereby, the outer side in the axial direction of the bearing 1 is sealed by the seal case 25 and the seal portion 27, and a seal space portion S is formed. Therefore, even when the grease is discharged into the seal space S during the rotation of the bearing, it is possible to prevent the grease from leaking to the outside of the bearing and at the same time, prevent foreign matter from entering the inside of the bearing.

  Furthermore, in addition to the sealing mechanism 24 </ b> A, the sealed bearing device 100 </ b> A of the present embodiment is provided with a rotating slinger 35 that is fixed to the inner ring 2 and rotates together with the inner ring 2.

  As shown in FIG. 2, the rotating slinger 35 has a cylindrical fixing portion 35a extending in a cylindrical shape along the rotation center axis Q, and extends substantially perpendicularly from the axially outer end of the cylindrical fixing portion 35a to the outer diameter side. And an annular stirring portion 35b.

  Returning to FIG. 1, an annular recess 9 b is formed in the outer peripheral surface 9 t of the inner ring large collar portion 9 at a position where the bearing space T is formed opposite to the end inner peripheral surface 3 t of the outer ring 3.

  Then, the rotating slinger 35 is fixed to the inner ring large collar portion 9 by fitting the cylindrical fixing portion 35a of the rotating slinger 35 into the annular recess 9b formed in the outer peripheral surface 9t. That is, the rotation slinger 35 and the inner ring 2 are fixed in the bearing space T formed by the outer peripheral surface of the inner ring large collar portion 9 and the end inner peripheral surface 3t of the outer ring 3 facing each other. In this state, the cylindrical fixing portion 35a has an axially outer end extending outward in the axial direction from the end surface 9a of the inner ring collar 9, and the stirring portion 35b extends from the axially outer end to the blocking plate of the fixed slinger 29. It extends substantially parallel to the portion 29b. In addition, the tip of the agitating portion 35b faces the inner side surface 25s of the axial extension portion 25b of the seal case 25 and is positioned in a non-contact state.

  As a result, the agitating portion 35b rotates with the inner ring 2 during rotation of the bearing, so that even when grease is discharged into the seal space S, the grease discharged into the seal space S is agitated so that the fixed slinger 29 Adhering to the inside is suppressed. Further, the agitation part 35b agitates the grease discharged into the seal space S, whereby the grease can be resupplied into the bearing, and the bearing life can be extended.

  Further, the annular recess 9b can be formed relatively easily by cutting the inner ring large collar part 9 or the like, and when both the inner ring 2 and the annular fixing member 19 are specially processed for assembly. Compared to the above, production costs can be suppressed. Further, since the rotating slinger 35 is fixed to the inner ring 2 simply by fitting the cylindrical fixing portion 35a to the annular recess 9b of the inner ring large collar portion 9b, the assemblability is good. Furthermore, since there is no member interposed between the inner ring 2 and the annular fixing member 19 and the inner ring 2 and the annular fixing member 19 only need to be brought into surface contact with each other, it is possible to prevent deterioration in assembling and improve the assembling accuracy.

The embodiment of the present invention has been specifically described above, but the present invention is not limited to this, and can be appropriately changed without departing from the spirit of the present invention.
For example, the stirring portion 35b is configured to extend from the axially outer end portion of the cylindrical fixing portion 35a to the outer diameter side substantially parallel to the blocking plate portion 29b of the fixed slinger 29, but the rotating slinger 9 has a bearing space. As long as it is fixed to the rotating wheel 2 within T, it is not limited to this.

  Moreover, the extension length to the outer-diameter side of the stirring part 35b can be set arbitrarily. For example, it may be arranged close to the inner side surface 25s of the axial extension portion 25b of the seal case 25 so as to form a labyrinth. As shown in FIG. 3, the inner side of the axial extension portion 25b of the seal case 25 The extension length of the stirring portion 35b may be shortened so that the axial clearance between the stationary slinger 29 and the blocking plate portion 29b is smaller than the radial clearance with the side surface 25s. As a result, the amount of grease resupplied inside the bearing can be limited, and an increase in bearing torque due to excessive grease inside the bearing can be prevented.

  Moreover, as shown to Fig.4 (a), you may provide the slit 60 extended radially at predetermined intervals in the circumferential direction in the stirring part 35b, and as shown to FIG.4 (b), predetermined intervals in the circumferential direction may be provided. In this case, a concave groove 61 having a concave outer peripheral surface may be provided. This also makes it possible to adjust the amount of grease resupplied inside the bearing, and to prevent an increase in bearing torque due to excessive grease inside the bearing.

  In addition, as shown in FIG. 5, the rotating slinger 35 may be provided with a folded portion 35 c on the inner side in the axial direction from the tip of the stirring portion 35 b. By forming a labyrinth gap between the outer peripheral surface 35s and the inner side surface 25s of the folded portion 35c, it is possible to more effectively suppress the grease from adhering to the inside of the fixed slinger 29. Furthermore, you may provide a slit (not shown) and a ditch | groove (not shown) in the said folding | returning part 35c with the predetermined space | interval in the circumferential direction.

  Furthermore, the sealed bearing device 100A of the present embodiment can be applied not only to a railway vehicle axle but also to various mechanisms. Further, the sealed bearing device 100A of the present embodiment exemplifies a tapered roller bearing as a bearing, but is not limited to this and can be applied to a cylindrical roller bearing and a self-aligning roller bearing. Further, the elastic body 33 may contact the other member fixed to the outer peripheral surface of the annular fixing member 19 without directly contacting the outer peripheral surface of the annular fixing member 19.

1 Tapered roller bearing 2 Inner ring (rotating ring)
2s Inner ring raceway surface 9 Inner ring large collar portion 9t Outer peripheral surface 9b Annular recess 3 Outer ring (fixed ring)
3s Outer ring raceway surface 3t End inner peripheral surface 5 Roller 11 Cage 17, 19 Oil drain (annular fixing member)
24A Sealing mechanism 25 Sealing case 27 Sealing part 29 Fixed slinger 31 Core metal 33 Elastic body 35 Rotating slinger 35a Cylindrical fixing part 35b Stirring part 100A Sealed bearing device S Sealing space part Q Rotating center axis T Bearing space

Claims (5)

A bearing including a rolling element that is rotatably arranged between the rotating wheel and the fixed wheel;
An annular fixing member for restricting movement of the rotating wheel in the axial direction from at least one axial side of the rotating wheel;
A sealing mechanism having a seal case attached to at least one axial direction of the fixed ring, and a seal portion that seals between the annular fixing member and the seal case;
A sealed bearing device used for grease lubrication by sealing the inside of the bearing,
A rotating slinger having a stirring unit that rotates together with the rotating wheel and stirs grease is fixed to the rotating wheel in a bearing space formed by the rotating wheel and the fixed wheel facing each other. Sealed bearing device. The rotating slinger includes a cylindrical fixing portion, and the stirring portion that extends from the end on the at least one axial direction side of the cylindrical fixing portion to the outer diameter side,
The sealed bearing device according to claim 1, wherein the cylindrical fixing portion is fitted to an outer peripheral surface of the flange portion.   The seal portion includes a metal core attached to the seal case side, an elastic body that constitutes a seal lip that is attached to the metal core and slidably contacts the annular fixing member or a portion fixed to the annular fixing member, The fixed slinger which comprises the part fixed to the said annular fixing member or the said annular fixing member, and the fixed slinger which is attached to the seal case side at the axial direction inner side from the said seal lip, or comprises a labyrinth seal. 2. The sealed bearing device according to 2.   The sealed bearing device according to any one of claims 1 to 3, wherein the agitating portion is provided with a plurality of slits in a circumferential direction, and the plurality of slits extend radially. The sealed bearing device according to any one of claims 1 to 3, wherein the agitating portion is provided with a plurality of concave grooves having a concave outer peripheral surface in the circumferential direction.

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