JP2012177418A - Sealing device for bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device for a bearing which secures sealability of a bering inner space by greatly enhancing a waterproof property, and thereby enables the bearing to be used continuously for a long period of time.SOLUTION: There is provided the sealing device for a bearing which is provided so as to cover the gap between a stationary ring constitution body (outer ring 1) always kept in a non-rotation state and a rotary ring constitution body (inner ring 3) arranged rotatably oppositely to the stationary ring constitution body, and includes an annular seal case 25 having its base end part 25e fitted to the stationary ring constitution body and its tip part 25t positioned not in contact with the rotary ring constitution body. The rotary ring constitution body has an annular recessed groove G which is formed by being partially recessed in a peripheral direction and in which the tip 25t of the seal case 25 is positioned in a state of being partially inserted, and the annular recessed groove G includes an external diameter-side tapered circumferential surface Gou inclined with respect to an axis Ax of rotation and an internal diameter-side tapered circumferential surface Gin opposed thereto.

Description

  The present invention makes it possible to prevent foreign matters (for example, water and dust) from entering the bearing inner space and to prevent leakage of lubricant (for example, oil and grease) sealed in the bearing inner space. The present invention relates to a bearing sealing device.

  Conventionally, as this type of bearing sealing device, as shown in Patent Documents 1 and 2, for example, those applied to railway vehicle axles are known. Various types of tapered roller bearings are used for railway vehicle axles. As an example, the tapered roller bearing shown in FIG. 4 is a stationary ring structure (for example, one outer ring 1) that is always kept in a non-rotating state. And a rotating wheel structure (for example, two inner rings 3) that is rotatably disposed opposite to the stationary wheel structure (outer ring 1).

  Further, in the stationary wheel constituting body and the rotating wheel constituting body, the outer ring 1 and each inner ring 3 are arranged to face each other so as to be relatively rotatable. In this case, each inner ring 3 is fitted to a railway vehicle axle 7 (hereinafter referred to as an axle 7) with the back surfaces of the inner rings 3 being applied to each other (for example, the spacer 5). 7 is fitted in a housing (not shown) facing the outer peripheral side.

  On the facing surfaces of the outer ring 1 and the inner ring 3, annular raceways (outer ring raceway surface 1s, inner ring raceway surface 3s) continuous in the circumferential direction are formed to face each other. In this case, the inner ring raceway surface 3s is formed so as to be inclined toward the end in a direction away from the spacer 5 side, while the outer ring raceway surface 1s is respectively along the inner ring raceway surface 3s. They are formed with the same inclination angle.

  Further, in the bearing internal space between the outer ring 1 and the inner ring 3, specifically, between the raceway surfaces 1s and 3s described above (that is, between the outer ring raceway surface 1s and the inner ring raceway surface 3s), there are a plurality of spaces. The rolling elements (rollers) 9 are rotatably incorporated in a state in which the rolling elements (rollers) 9 are held by the cage 11 one by one, thereby forming one tapered roller bearing. In addition, in order to guide along each inner ring raceway surface 3 s while holding each rolling element (roller) 9, flange portions 13 and 15 are provided on the opposing surface (that is, the outer circumferential surface) of the inner ring 3, and each inner ring raceway. It is continuous along both sides of the surface 3s and is provided so as to protrude from the inner ring raceway surface 3s.

  Further, as the rotating wheel constituting body, on both outer sides in the axial direction of the two inner rings 3, an annular front lid 17 and an annular rear lid 19 which are continuous along the circumferential direction are provided adjacent thereto. The front lid 17 and the rear lid 19 are fitted to the axle 7. In this case, for example, the rear lid 19 is fitted to the axle 7, the tapered roller bearing described above is fitted to the axle 7 and applied to the rear lid 19, and then the front lid 17 is fitted to the axle 7. Then, a predetermined preload can be applied to the tapered roller bearing by applying the pressing body 21 to the front lid 17 in the axial direction and tightening with the bolts 23 in a state of being applied to the tapered roller bearing. .

  According to such a tapered roller bearing, a plurality of rolling elements (rollers) incorporated between the outer inner rings 1 and 3 (that is, the bearing inner space) while the outer inner rings 1 and 3 rotate relative to each other (while the bearing is rotating). The axle 7 can be smoothly rotated by rolling along the track surfaces 1 s and 3 s while being held and guided by the flange portions 13 and 15. At this time, the outer inner rings 1 and 3 and the axle 7 rotate around a common rotation axis Ax.

  In addition, in the tapered roller bearing, a predetermined amount of lubricant (for example, oil, grease) is sealed in the bearing internal space in order to keep the lubrication performance and the rotation performance during rotation of the bearing constant. In this case, in order to prevent leakage of lubricant (for example, oil, grease) sealed in the bearing inner space and to prevent foreign matters (for example, water, dust) from entering the bearing inner space, A sealing device for a bearing is provided between the rotating wheel component and the rotating wheel component.

  The bearing sealing device covers a gap (gap) between the axially outer sides of the stationary wheel component (for example, one outer ring 1) and the axially outer sides of the rotating wheel component (for example, two inner rings 3). As such, each is provided. In this case, one bearing sealing device has an annular seal case 25 whose base end portion 25e is fitted (fixed) to the outer ring 1 and whose distal end portion 25t is positioned in a non-contact state with respect to the front lid 17. The other bearing sealing device has an annular shape whose base end portion 25e is fitted (fixed) to the outer ring 1 and whose distal end portion 25t is positioned in a non-contact state with respect to the rear lid 19. A seal case 25 is provided.

  Each seal case 25 has the same shape as each other, and has a tapered shape as it goes from the base end portion 25e to the tip end portion 25t, thereby forming an external shape of a hollow truncated cone as a whole. Has been. The seal case 25 is provided so as to cover the gap between the stationary wheel component and the rotating wheel component, thereby enabling the bearing inner space to be maintained in a sealed state (under the environment). Yes.

  In addition, each seal case 25 is provided with a set portion 25 s that enables the existing various sealing members 27 to be set (accommodated and disposed) between the seal case 25 and the front lid 17 (rear lid 19). ing. In this case, as the sealing member 27, various types such as a lip seal, a pack seal, or a sealing plate such as a seal or a shield can be set.

  In the drawing, as an example, the sealing member 27 is fixed to the seal case 25, and an annular slinger 27 a extending toward the rotating wheel structure (in the drawing, the front lid 17 (rear lid 19) as an example), and a slinger An annular seal member 27b that is fixed to the inner diameter side of 27a and extends toward the rotating wheel constituting body is provided. The extending end of the slinger 27a is positioned in a non-contact state with respect to the rotating wheel component, while the extending end of the seal member 27b is positioned in contact with the rotating wheel component. Yes.

JP-A-9-68232 JP 2008-19905 A

  By the way, as shown in FIG. 5, in the seal case 25 applied to the conventional bearing sealing device, the annular tip 25t positioned in a non-contact state with respect to the front lid 17 (rear lid 19) The lid 17 (rear lid 19) is positioned in a state where a part thereof is inserted into an annular groove G in which the lid 17 (rear lid 19) is continuously depressed along the circumferential direction.

  In this case, the annular concave groove G is configured such that the inner diameter surface Min and the outer diameter surface Mout are both parallel to the rotation axis Ax, while the annular tip 25t is formed on the rotation axis Ax. It is configured to be parallel (specifically, the inner diameter surface Tin and the outer diameter surface Tout are both parallel to the rotation axis Ax).

  In this case, since the inner diameter surfaces Min and Tin of the annular groove G and the tip portion 25t and the outer diameter surfaces Mout and Tout are parallel to each other, the gap between the annular groove G and the tip portion 25t. A gap extending in parallel to the rotation axis Ax is formed. According to such a configuration, for example, rain water or snow water in which snow has melted easily enters the above-described gap, and conversely, it is difficult to flow out and thus easily collects.

  Here, for example, when the sealing member 27 (specifically, the seal member 27b) is deteriorated, rainwater or snow water collected in the gaps described above passes through the seal member 27 into the bearing internal space. As a result, the lubricant deteriorates and the bearing structure (outer ring 1, inner ring 3, each rolling element (roller) 9, outer ring raceway surface 1s, inner ring raceway surface 3s, etc.) rusts and peels off. May occur. If it becomes so, it may become difficult to continue using the said tapered roller bearing continuously over a long period of time.

  The present invention has been made in order to solve such a problem, and the object thereof is to dramatically improve the waterproof property, thereby ensuring the sealability of the bearing internal space, and thereby the bearing can be used for a long time. It is an object of the present invention to provide a bearing sealing device that enables continuous use.

In order to achieve such an object, the present invention provides a gap between a stationary wheel component that is always maintained in a non-rotating state and a rotating wheel component that is rotatably disposed opposite the stationary wheel component. An annular sealing case having a base end portion fitted to a stationary ring constituent body and positioned in a non-contact state with respect to the rotating wheel constituent body, the bearing sealing device provided so as to cover A ring-shaped concave groove that is formed in the rotating wheel structure so as to be continuously depressed in the circumferential direction and is positioned with the tip portion of the seal case inserted therein. The annular groove is provided with an outer diameter-side tapered circumferential surface inclined with respect to the rotation axis and an inner diameter-side tapered circumferential surface facing the outer circumferential side.
In the present invention, the outer diameter side tapered circumferential surface is inclined with a tapered gradient with respect to the rotation axis, and the inner diameter side tapered circumferential surface is inclined with a divergent gradient with respect to the rotation axis. ing.
In the present invention, the outer diameter side tapered circumferential surface is provided with at least one annular drain groove that is partially recessed in the circumferential direction along a direction crossing the rotation axis.
In the present invention, in the annular seal case, the tip end portion is configured to have a predetermined inclination angle with respect to the rotation axis and to have a shape spreading toward the annular concave groove.
In the present invention, the annular seal case is provided with a set portion that enables various sealing members to be set.

  According to the present invention, a sealing device for a bearing that ensures the sealability of the bearing internal space by dramatically improving the waterproofness, thereby enabling the bearing to be continuously used for a long period of time. Can be realized.

It is sectional drawing which expands and partially shows the structure of the bearing sealing device which concerns on one Embodiment of this invention, Comprising: (a) is sectional drawing which shows the structure of a front cover (rotary ring structure), (b) FIG. 4 is a cross-sectional view showing a state in which a seal case is provided between an outer ring (stationary wheel constituent body) and a front lid (rotating wheel constituent body), and (c) shows a configuration of the rear lid (rotating wheel constituent body). Sectional drawing shown, (d) is a sectional view showing a state in which a seal case is provided between an outer ring (stationary wheel constituent body) and a rear lid (rotating wheel constituent body). Sectional drawing which expands and shows a part of structure of the seal case of the sealing device for bearings concerning one Embodiment of this invention. Sectional drawing which expands and partially shows the structure of the sealing device for bearings which concerns on the modification of this invention. Sectional drawing which shows the structure of the sealing device for bearings applied to the railway vehicle axle. Sectional drawing which expands and shows a part of structure of the conventional sealing device for bearings.

  Hereinafter, a bearing sealing device according to an embodiment of the present invention will be described with reference to the accompanying drawings. In addition, since the following embodiment is an improvement of the bearing sealing device shown in FIG. 4, only the improved portion will be described below. In this case, with respect to the same configuration as the above-described bearing sealing device (FIG. 4), the same reference numerals as those used in the configuration are attached to the drawings used in this embodiment, and the description thereof is omitted. To do.

  As shown in FIGS. 1 (a) to 1 (d), the bearing sealing device according to the present embodiment includes both axially outer sides of a stationary ring structure (for example, one outer ring 1) that is always maintained in a non-rotating state. The rotating wheel structure (for example, the two inner rings 3) disposed so as to be able to rotate opposite the stationary wheel structure (outer ring 1) is provided so as to cover the space (gap) between both axial outer sides. ing. In this case, each bearing sealing device has a base end portion 25e fitted to a stationary ring structure (for example, the outer ring 1), and a tip end portion 25t having a rotating ring structure (for example, the front lid 17 and the rear lid 19). ) With an annular seal case 25 positioned in a non-contact state.

  In such a configuration, the front lid 17 (rotating wheel component) is formed to be continuously depressed along the circumferential direction, and the tip 25t of the seal case 25 is partially inserted. An annular groove G positioned in a state is formed (FIGS. 1A and 1B). Similarly, the rear lid 19 (rotating wheel constituent body) is formed in a state of being partially depressed continuously along the circumferential direction, and the distal end portion 25t of the seal case 25 is positioned in a state where the portion is inserted. An annular groove G is formed (FIGS. 1C and 1D).

  Further, each concave groove G of the front lid 17 and the rear lid 19 is formed on an outer diameter side taper circle inclined with respect to one rotation axis Ax (see FIG. 4) common to the outer inner rings 1 and 3 and the axle 7 described above. A circumferential surface Gout and an inner diameter-side tapered circumferential surface Gin facing this (specifically, facing the inner diameter side thereof) are provided. In this case, the outer diameter side tapered circumferential surface Gout is inclined with a taper gradient with respect to the rotation axis Ax, while the inner diameter side taper circumferential surface Gin has a divergent gradient with respect to the rotation axis. Then tilted.

  Thereby, the outer diameter side tapered circumferential surface Gout is configured to form a hollow truncated cone shape that is tapered toward the insertion direction of the distal end portion 25t of the seal case 25 inserted into the concave groove G. On the other hand, the taper circumferential surface Gin on the inner diameter side forms a hollow inverted truncated cone shape that becomes wider toward the insertion direction of the distal end portion 25t of the seal case 25 inserted into the concave groove G. Has been.

  In this case, each concave groove G of the front lid 17 and the rear lid 19 has an inclination angle θ1 with respect to the rotation axis Ax of the outer diameter side tapered circumferential surface Gout that forms a tapered hollow cone shape, and a hollow inverted cone shape that widens toward the end. The inclination angle θ2 of the inner diameter side tapered circumferential surface Gin with respect to the rotation axis Ax is set according to, for example, the use environment or purpose of the bearing sealing device, and is not specifically limited here. In short, the inclination angles θ1 and θ2 may be set in a range of 0 ° or more and less than 90 ° (0 ° <θ1, θ2 <90 °) with respect to the rotation axis Ax.

  Further, in each concave groove G of the front lid 17 and the rear lid 19, a part of the outer circumferential side tapered circumferential surface Gout is circumferentially crossed along the direction of rotation axis Ax (as an example, orthogonal). At least one annular drain groove 29 continuously depressed in the direction is provided. In the drawing, one annular drain groove 29 is shown as an example, but the technical scope of the invention is not limited thereby.

  The groove width, groove depth, and groove shape of the draining groove 29 are set according to the size (width) and shape of the groove G, or the use environment and purpose of the bearing sealing device, for example. There is no particular limitation here. For example, in the drawing, the draining groove 29 having a rectangular cross section is shown, but instead of this, a draining groove 29 having a circular arc (elliptical) shape or a triangular shape may be used.

  Further, as shown in FIG. 2, in the annular seal case 25, the tip portion 25t forms a predetermined inclination angle α with respect to the rotation axis Ax, and the annular groove G (FIG. 1 (a)). To (d)). Specifically, both the inner diameter surface Tin and the outer diameter surface Tout are configured to form a predetermined inclination angle α with respect to the rotation axis Ax. In this case, the inclination angle α of the distal end portion 25t with respect to the rotation axis Ax is set according to, for example, the use environment or purpose of the bearing sealing device, and is not specifically limited here. In short, the inclination angle α may be set in a range of 0 ° or more and less than 90 ° (0 ° <α <90 °) with respect to the rotation axis Ax.

  The above-described seal case 25 includes two rotating wheel components (two rotators arranged so as to be rotatable in opposition to the stationary wheel component (outer ring 1) and both axially outer sides of the stationary wheel component (outer ring 1). The same thing can be applied and provided between the outer sides (gap) of the inner ring 3) in the axial direction (see FIGS. 1B and 1D).

  In addition, the annular seal case 25 is provided with a set portion 25s that allows the existing various sealing members 27 to be set. The set portion 25s is formed in a hollow cylindrical shape parallel to the rotation axis Ax between the base end portion 25e and the tip end portion 25t of the seal case 25 that forms the appearance of a truncated cone as a whole.

  In this case, the sealing member 27 is set (accommodated and disposed) in the set portion 25s, and a part (tip) of the sealing member 27 is in contact with or not in contact with the rotating wheel structure (the front lid 17 and the rear lid 19 as an example in the drawing). By bringing them into contact with each other, various existing sealing members 27 are accommodated between the seal case 25 (specifically, the set portion 25s) and the rotating wheel component (the front lid 17 and the rear lid 19). Can be arranged.

  In the drawings, as an example of the sealing member 27, a lip seal is applied as the sealing member 27b (see FIG. 4), but this does not limit the technical scope of the present invention. In place of the lip seal, for example, various types such as a pack seal or a sealing plate such as a seal or a shield can be set as the sealing member 27.

  As described above, according to the bearing sealing device of the present embodiment, the distal end portion 25t of the seal case 25 that forms the appearance of the hollow cone is configured to have a divergent shape that forms a predetermined inclination angle α with respect to the rotation axis Ax. The tip 25t is inserted into a concave groove G having outer and inner diameter tapered circumferential surfaces Gout and Gin to be positioned in a non-contact state, and a draining groove 29 is provided in the outer diameter side tapered circumferential surface Gout. Thus, during rotation of the axle 7 (that is, during relative rotation of the outer inner rings 1 and 3) or when the axle 7 is stopped, for example, rain water or snow water in which snow has melted, a part of the tip of the seal case 25 Along with 25t, it falls and is eliminated by its own weight, and the rest is cut by the drain groove 29 of the concave groove G formed in the rotating wheel constituting body (the front lid 17 and the rear lid 19), and the outer diameter side taper circumference Drops along the plane Gout and is eliminated.

  Thereby, it is possible to prevent rainwater and snowwater from entering the above-described bearing internal space beyond the bearing sealing device. In particular, rain water or snow water cut by the water draining groove 29 during rotation of the axle 7 (that is, during relative rotation of the outer inner rings 1 and 3 (during bearing rotation)) is caused by its own weight. Or fall along the outer circumferential side taper circumferential surface Gout of the concave groove G by the rotational centrifugal force of the rotating wheel component (the front lid 17 and the rear lid 19). Is done.

  According to this, since it is possible to reliably prevent rain water or snow water from entering the bearing internal space, for example, rain water or snow water enters the bearing internal space through the seal member 27. Thus, conventional problems such as deterioration of the lubricant and rusting of the bearing configuration (outer ring 1, inner ring 3, each rolling element (roller) 9, outer ring raceway surface 1s, inner ring raceway surface 3s, etc.) may occur. Will not occur. As a result, the tapered roller bearing can be continuously used for a long time.

  Further, according to the present embodiment, since various existing sealing members 27 can be set on the set portion 25s of the seal case 25, the synergistic effect of the above-described bearing sealing device and the sealing member 27 can be obtained. In addition to the rain water and snow water described above, other foreign matters (for example, dust) can be reliably prevented from entering the bearing internal space, and lubricant (for example, oil, grease) enclosed in the bearing internal space can be prevented. ) Can be reliably prevented.

  As a result, seizure and deterioration due to foreign matter can be prevented, and the lubricant (for example, oil, grease) sealed in the bearing internal space can always be maintained at a constant amount. The inside lubrication performance and rotation performance can be maintained constant, and as a result, the tapered roller bearing can be continuously used for a long time.

  For example, as shown in FIG. 3, in the above-described embodiment, as the sealing member 27, the rotating wheel is interposed between the sealing member (lip seal) 27 b and the rotating wheel component (the front lid 17 and the rear lid 19). A sleeve 30 that rotates together with the component may be interposed, and the seal member (lip seal) 27 b may be in contact with the sleeve 30.

1 Outer ring (stationary ring component)
3 Inner ring (Rotating wheel component)
25 Seal case 25e Seal case base end 25t Seal case tip Ax Rotating shaft G Concave groove Gout Concave groove outer diameter taper circumferential surface Gin Concave groove inner diameter side taper circumferential surface

Claims (5)

A bearing sealing device provided so as to cover between a stationary wheel component that is always maintained in a non-rotating state and a rotating wheel component that is rotatably disposed opposite the stationary wheel component,
The base end portion is fitted to the stationary wheel constituent body, and the distal end portion has an annular seal case positioned in a non-contact state with respect to the rotating wheel constituent body,
The rotating wheel structure is formed with an annular concave groove that is continuously depressed along the circumferential direction and is positioned with the tip of the seal case inserted partially. And
The annular concave groove includes an outer diameter side tapered circumferential surface inclined with respect to the rotation axis, and an inner diameter side tapered circumferential surface facing the outer circumferential side taper circumferential surface.   The outer diameter side tapered circumferential surface is inclined with a tapered gradient with respect to the rotation axis, and the inner diameter side tapered circumferential surface is inclined with a divergent gradient with respect to the rotation axis. The bearing sealing device according to claim 1.   The outer diameter side tapered circumferential surface is provided with at least one annular drain groove that is partially recessed in the circumferential direction along a direction crossing the rotation axis. The bearing sealing device according to claim 2.   The annular seal case has a tip end portion that forms a predetermined inclination angle with respect to the rotation axis and has a divergent shape toward the annular concave groove. The bearing sealing device according to any one of 1 to 3.   The bearing sealing device according to any one of claims 1 to 4, wherein the annular seal case is provided with a set portion that enables various sealing members to be set.

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