JP6771739B2 - Sealed structure - Google Patents

Description

The present invention relates to a sealing structure, and more particularly to a sealing device used for a hub bearing of a vehicle or the like.

Conventionally, in a vehicle, for example, an automobile, a hub bearing (wheel bearing device) that rotatably supports a wheel is provided with a sealing device for sealing the inside of the hub bearing from the outside (for example, Patent Document). See 1.).

Hub bearings used in automobiles, especially passenger cars, have a sealing structure in which a sealing device is integrally attached to the outer ring of the hub bearing in advance. For example, as shown in FIG. 10, the hub bearing 100 has an annular outer ring 101 with respect to the axis x and an annular inner ring 102 at least partially surrounded by the outer ring 101. The outer peripheral side end portion 101a on the outer peripheral side (arrow c direction) of the outer ring 101 and the flange portion 102a of the inner ring 102 are arranged to face each other.

A sealing device 110 is press-fitted between the outer ring 101 and the inner ring 102. The sealing device 110 is integrally mounted with the outer ring 101 on the fixed side in a fitted state, and includes a reinforcing ring 111 and an elastic body portion 112. The reinforcing ring 111 is integrally formed with the elastic body portion 112 in a state of being covered with the elastic body portion 112.

The elastic body portion 112 extends in the arrow cd direction (hereinafter, also referred to as “diameter direction”) perpendicular to the direction along the axis x (hereinafter, this is also referred to as “axis x direction”). And, which is provided on the inner peripheral side (direction of arrow c) from the main body 112a and corresponds to the inner surface (hereinafter, also referred to as "inner side surface") 102am of the flange portion 102a of the inner ring 102. It is provided with side lips 113 and 114 in contact with each other.

In this case, a slight gap H is formed between the main body 112a of the elastic body portion 112 mounted on the outer peripheral side end portion 101a of the outer ring 101 and the inner side surface 102am of the flange portion 102a of the inner ring 102. , This gap H functions as a labyrinth seal that suppresses the intrusion of foreign matter from the outside.

JP-A-2015-155709

However, in the sealing device 110 having the above-described configuration, if the gap H (entrance port) between the main body 112a of the elastic body portion 112 in the outer ring 101 and the inner side surface 102am of the flange portion 102a of the inner ring 102 is narrowed, the outside It is possible to further suppress the invasion of foreign substances such as muddy water and dust, but on the other hand, there is a risk that the foreign substances once invaded from the gap H will be difficult to be discharged.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a sealing structure capable of suppressing the invasion of foreign matter and at the same time easily discharging the once invaded foreign matter to the outside.

In order to achieve the above object, in the present invention, the outer peripheral side of the bearing device including an annular outer peripheral side member that can rotate relative to each other with respect to the axis and an annular inner peripheral side member surrounded by the outer peripheral side member. It has a sealing structure for sealing between a member and the inner peripheral side member, and includes a sealing device attached to the outer peripheral side member and a slinger attached to the inner peripheral side member, and the sealing device includes the sealing device. It has a seal lip that contacts the facing surface of the slinger arranged to face the device and seals between the outer peripheral side member and the inner peripheral side member, and is attached to the outer peripheral side member or the outer peripheral side member. A labyrinth seal is formed by the gap when the sealing device and the slinger are arranged to face each other, and is provided with respect to the facing surface of the slinger and extends radially from the inner peripheral side to the outer peripheral side about the axis. It has a plurality of protrusions arranged at predetermined intervals, and the width of the plurality of protrusions is gradually expanded from the inner peripheral side to the outer peripheral side.

The present invention is characterized in that the protrusion is formed so that its height gradually increases from the inner peripheral side to the outer peripheral side.

The present invention is characterized in that the protrusion has a symmetrical shape that is cut in half along an axis along the longitudinal direction of the protrusion.

In the present invention, the outer peripheral side member and the inner peripheral side member of a bearing device including an annular outer peripheral side member that can rotate relative to each other with respect to the axis and an annular inner peripheral side member surrounded by the outer peripheral side member. It has a sealing structure for sealing between the spaces, and includes a sealing device attached to the outer peripheral side member, and the sealing device contacts the facing surface of the inner peripheral side member arranged to face the sealing device and the outer peripheral side. When it has a seal lip that seals between the side member and the inner peripheral side member, and the sealing device attached to the outer peripheral side member or the outer peripheral side member and the inner peripheral side member are arranged to face each other. A plurality of protrusions radially arranged at predetermined intervals, which form a labyrinth seal by the gap, are provided with respect to the facing surface of the inner peripheral side member, and extend from the inner peripheral side to the outer peripheral side about the axis. The plurality of protrusions are characterized in that their widths are gradually expanded from the inner peripheral side to the outer peripheral side.

According to the sealing device according to the present invention, it is possible to realize a sealing structure capable of suppressing the invasion of foreign matter and at the same time easily discharging the once invaded foreign matter to the outside.

It is sectional drawing which shows the whole schematic structure of the sealed structure which concerns on 1st Embodiment of this invention. It is a partially enlarged sectional view which shows the labyrinth structure by the sealing device and the protrusion which concerns on 1st Embodiment. It is a figure which shows the structure of the protrusion | portion which concerns on 1st Embodiment. It is a schematic perspective view which shows the other structure of the protrusion | region which concerns on 1st Embodiment. It is sectional drawing which shows the whole schematic structure of the sealed structure which concerns on 2nd Embodiment of this invention. It is a partially enlarged sectional view which shows the labyrinth structure by the sealing device and the protrusion which concerns on 2nd Embodiment. It is a schematic perspective view which shows the structure of the protrusion part which concerns on 2nd Embodiment. It is the A arrow view of the protrusion which concerns on 2nd Embodiment. It is a B arrow view of the protrusion according to the second embodiment. It is a partial cross-sectional view which shows the use state of the conventional sealing apparatus.

Hereinafter, the first and second embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a cross-sectional view showing an overall schematic configuration of a sealed structure according to a first embodiment of the present invention. FIG. 2 is a partially enlarged cross-sectional view showing a labyrinth structure with a sealing device and protrusions according to the first embodiment. FIG. 3 is a diagram showing a configuration of a protrusion according to the first embodiment. FIG. 4 is a schematic perspective view showing another configuration of the protrusion according to the first embodiment.

Hereinafter, for convenience of description, the outside is the arrow a direction in the axis x direction in FIGS. 1 to 4, and the inside is the arrow b direction in the axis x direction. That is, the outside is the side in the direction facing the outside of the hub bearing 50, and the side in the direction facing the atmosphere where foreign matter is present. The inside is the side in the direction facing the inside of the hub bearing 50. Further, in the radial direction perpendicular to the axis x, the direction away from the axis x (arrow c direction) is the outer peripheral side, and the direction closer to the axis x (arrow d direction) is the inner peripheral side.

<Sealed structure>
The sealing structure 10 according to the first embodiment of the present invention is realized by the sealing device 1 mounted on the outer ring 51 of the hub bearing 50 as a bearing device and the slinger 20 fixed to the inner ring 54, and is realized by the outer ring 51. It seals between the inner ring 54 and the inner ring 54.

The hub bearing 50 has an annular outer ring 51 as an outer peripheral member centered on the axis x and an inner circumference centered on the axis x that is rotatable relative to the outer ring 51 and is partially surrounded by the outer ring 51. An annular hub 52 as a side member and a plurality of bearing balls 53 arranged between the outer ring 51 and the hub 52 are provided.

The outer ring 51 is a fixing member, and has an outer peripheral surface 51a on the outer peripheral side and a flat outer (arrow a direction) end surface (hereinafter referred to as this) along a radial direction (arrow cd direction) perpendicular to the outer peripheral surface 51a. It has (referred to as "outer end face") 51b.

Specifically, the hub 52 has an inner ring 54 and a hub ring 55. The inner ring 54 is integrally fixed with the hub ring 55. The hub wheel 55 is a rotating member, and wheels (not shown) are attached to the wheel mounting flange 56 of the hub wheel 55 by a plurality of hub bolts 57.

A drive shaft (not shown) is inserted into the through hole of the hub wheel 55. The drive shaft is spline-coupled to the hub wheel 55, the hub wheel 55 rotates with the rotation of the drive shaft, and the wheels mounted via the wheel mounting flange 56 of the hub wheel 55 rotate.

In the hub bearing 50, the sealing device 1 and the sealing device 1 and the sealing device 1 are sealed in the annular space (hereinafter referred to as "annular space") 5a and 5b between the inner peripheral surface of the outer ring 51 and the inner peripheral surface of the inner ring 54 and the hub ring 55. The device 6 is attached in a press-fitted state. Although different sealing devices 1 and 6 are attached to the hub bearing 50, two sealing devices 1 having the same structure or two sealing devices 6 having the same structure may be attached.

The sealing devices 1 and 6 prevent the lubricant from leaking from the annular spaces 5a and 5b provided with the bearing balls 53 and the like of the hub bearing 50, and rainwater, muddy water, dust and the like in the annular spaces 5a and 5b. Prevents foreign matter from entering from the outside. Although the sealing device 1 and the sealing structure 10 by the slinger 20 will be described with reference to FIG. 2, the sealing device 1 is not limited to the one having the configuration shown or described later, and has other known configurations. It may be a thing.

As shown in FIG. 2, the sealing device 1 attached to the outer ring 51 of the hub bearing 50 has an elastic body portion 11 formed of an annular elastic body centered on the axis x and the elastic body portion 11 on the outside (direction of arrow a). ) Is covered and integrally attached, and an annular metal reinforcing ring 12 centered on the axis x is provided.

Examples of the elastic body of the elastic body portion 11 include various rubber-like elastic members. The rubber-like elastic member is, for example, a synthetic rubber such as ditrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), and fluororubber (FKM). The elastic body portion 11 is molded by cross-linking (vulcanization) molding using a molding die.

The elastic body portion 11 has a base portion 14, and the base portion 14 has a side lip 15, an outer radial lip 17, and an inner radial lip, which are portions extending outward (in the direction of arrow a) from the base portion 14. Has 19.

The side lip 15 as a seal lip is located on the outer peripheral side (direction of arrow c) with respect to the outer radial lip 17, and its tip portion extends outward (direction of arrow a). The side lip 15 has a predetermined tightening allowance (contact width), and its tip abuts on the inner surface (hereinafter, also referred to as “inner side surface”) 20i of the slinger 20 (in the direction of arrow b). Will be done.

The outer radial lip 17 as a seal lip is located on the inner peripheral side (arrow d direction) of the side lip 15, and its tip portion extends diagonally to the outer (arrow a direction) and inner peripheral side (arrow d direction). ing. The outer radial lip 17 has a predetermined tightening allowance, and the tip portion thereof is in contact with the inner side surface 20i of the slinger 20.

The inner radial lip 19 as a seal lip is located on the inner peripheral side (arrow d direction) of the side lip 15 and inside (arrow b direction) of the outer radial lip 17, and its tip is inside (arrow). It extends diagonally to the inner circumference side (arrow d direction) (direction b).

The reinforcing ring 12 reinforces the elastic body portion 11, and is made of a metal material. Examples of the metal material include stainless steel and SPCC (cold rolled steel). An elastic body portion 11 is attached to the reinforcing ring 12 from the outer peripheral side (direction of arrow c) and the outside (direction of arrow a).

The reinforcing ring 12 is manufactured by, for example, press working or forging, and is arranged in a molding die when the elastic body portion 11 is formed by cross-linking (vulcanization) molding. In the reinforcing ring 12, the elastic body portion 11 is adhered to the reinforcing ring 12 by cross-linking, so that the elastic body portion 11 is integrally formed with the reinforcing ring 12.

The reinforcing ring 12 includes a cylindrical cylindrical portion 12a located on the outermost peripheral side and a hollow disk-shaped disk portion 12b extending from the inner end (arrow b direction) of the cylindrical portion 12a to the inner peripheral side (arrow d direction). And have. Specifically, the reinforcing ring 12 is formed so that the cylindrical portion 12a is fitted to the inner peripheral surface of the outer ring 51.

The slinger 20 is arranged to face the sealing device 1 in the x direction of the axis. The slinger 20 is made of metal, for example, stainless steel, and is a plate-shaped annular member centered on the axis x. The slinger 20 is fixed to a surface (hereinafter, also referred to as an "outer peripheral surface") 54a on the outer peripheral side (arrow c direction) of the outer (arrow a direction) end of the inner ring 54, and is generally outer peripheral. It extends toward the side (direction of arrow c).

The slinger 20 includes an inner peripheral side cylindrical portion 20a, an inner peripheral side flange portion 20b, a central cylindrical portion 20c, an outer peripheral side flange portion 20d, and an outer peripheral side cylindrical portion 20e.

The inner peripheral side cylindrical portion 20a is an annular tubular portion that is fitted on the outer peripheral surface 54a of the inner ring 54 and is located on the innermost peripheral side (arrow d direction) with respect to the axis x. The tip portions of the outer radial lip 17 and the inner radial lip 19 of the sealing device 1 are brought into contact with the inner peripheral side cylindrical portion 20a.

The inner peripheral side flange portion 20b is a hollow disk-shaped portion centered on the axis x that extends from the outer (arrow a direction) end of the inner peripheral side cylindrical portion 20a to the outer peripheral side (arrow c direction). The tip of the side lip 15 of the elastic body portion 11 is brought into contact with the facing surface (that is, the inner side surface 20i) facing the elastic body portion 11 of the sealing device 1 on the inner peripheral side flange portion 20b.

That is, the outer ring 51 and the inner ring 54 are sealed by the side lip 15, the outer radial lip 17, and the inner radial lip 19 of the elastic body portion 11 in the sealing device 1.

The central cylindrical portion 20c is an annular tubular portion centered on the axis x extending from the end portion on the outer peripheral side (arrow c direction) of the inner peripheral side flange portion 20b to the outside (arrow a direction). The outer peripheral side flange portion 20d is a hollow disk-shaped portion centered on the axis x that extends from the outer (arrow a direction) end of the central cylindrical portion 20c to the outer peripheral side (arrow c direction). The outer peripheral side cylindrical portion 20e is an annular tubular portion centered on the axis x extending inward (in the direction of arrow b) from the end portion on the outer peripheral side (arrow c direction) of the outer peripheral side flange portion 20d.

The central cylindrical portion 20c, the outer peripheral side flange portion 20d, and the outer peripheral side cylindrical portion 20e of the slinger 20 are portions surrounding the outer peripheral surface 51a and the outer end surface 51b of the outer ring 51.

A gap g1 is formed between the outer peripheral surface 51a of the outer ring 51 and the outer peripheral side cylindrical portion 20e, and a gap g2 is also formed between the outer end surface 51b of the outer ring 51 and the outer peripheral side flange portion 20d. , G2 functions as a labyrinth seal. The interval of the gap g1 and the interval of the gap g2 may be the same, and the interval of the gap g2 may be narrower or wider than the interval of the gap g1.

As shown in FIGS. 2 and 3A, the facing surface 20ds of the outer peripheral flange portion 20d facing the outer end surface 51b of the outer ring 51 is from the inner peripheral side (arrow d direction) to the outer peripheral side with the axis x as the center. A plurality of protrusions 21 extending in the direction of (arrow c direction) are provided.
These plurality of protrusions 21 are arranged radially and at predetermined intervals in the circumferential direction with respect to the facing surface 20ds of the outer peripheral side flange portion 20d with the axis x as the center.

These plurality of protrusions 21 are made of various rubber-like elastic members, and are crosslinked (vulcanized) bonded to the facing surface 20ds of the outer peripheral flange portion 20d of the slinger 20. Examples of the rubber-like elastic member are synthetic rubbers such as ditrill rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), and fluororubber (FKM).

As shown in FIG. 3A, the protrusion 21 is a portion of the slinger 20 that protrudes inward (in the direction of arrow b) from the facing surface 20ds of the outer peripheral flange portion 20d, and is shown in FIG. 3B. As shown, the width is gradually expanded from the end portion 21a on the inner peripheral side (direction of arrow d) to the end portion 21b on the outer peripheral side (direction of arrow c).

Further, as shown in FIG. 3C, the height of the protruding portion 21 gradually increases from the end portion 21a on the inner peripheral side (arrow d direction) toward the end portion 21b on the outer peripheral side (arrow c direction). It is formed to be. Specifically, the protrusion 21 has a symmetrical outer shape such that a bullet is cut in half along the axis z.

<Foreign matter intrusion suppression operation and foreign matter discharge operation>
In such a sealing structure 10, the slinger 20 faces the outer end surface 51b of the outer ring 51 and faces the facing surface 20ds of the outer peripheral side flange portion 20d from the inner peripheral side (arrow d direction) to the outer peripheral side (arrow c direction). A plurality of protrusions 21 extending radially and arranged at predetermined intervals in the circumferential direction are provided.

The width of these plurality of protrusions 21 is gradually expanded from the end portion 21a on the inner peripheral side (arrow d direction) toward the end portion 21b on the outer peripheral side (arrow c direction), and the inner peripheral side (arrow). It is formed so that its height gradually increases from the end portion 21a in the d direction) toward the end portion 21b on the outer peripheral side (arrow c direction).

Therefore, as shown in FIG. 2, when the slinger 20 is integrally rotated with the rotation of the inner ring 54, the gap g2 between the outer ring 51 and the slinger 20 is provided by the plurality of radially arranged protrusions 21. Can generate an airflow Ar from the inner peripheral side (direction of arrow d) to the outer peripheral side (direction of arrow a).

As a result, it is possible to prevent foreign matter from entering through the gap g1 between the outer peripheral surface 51a of the outer ring 51 and the outer peripheral side cylindrical portion 20e of the slinger 20 by the airflow Ar generated by the protrusion 21. Is able to discharge the foreign matter to the outside by the airflow Ar generated by the protrusion 21 even when the foreign matter invades the inner circumference side (direction of arrow d) from the protrusion 21.

Since the protrusion 21 has a shape symmetrical with respect to the axis z, the inner ring 54 is rotated in either the clockwise direction or the counterclockwise direction when viewed from the outside (arrow a direction). Also, it is possible to generate an airflow Ar from the inner peripheral side (direction of arrow d) to the outer peripheral side (direction of arrow a) to suppress or prevent the invasion of foreign matter.

Further, since the plurality of protrusions 21 are made of rubber-like elastic members, the gap g2 between the outer peripheral surface 51a of the outer ring 51 and the facing surface 20ds of the outer peripheral flange portion 20d of the slinger 20 is narrowed. Even when the sealing property is improved and the protrusion 21 comes into contact with the outer peripheral surface 51a of the outer ring 51, the damage to the outer ring 51 can be reduced.

Thus, in the hub bearing 50, it is possible to realize a sealed structure 10 capable of suppressing the invasion of foreign matter and at the same time easily discharging the once invaded foreign matter to the outside.

In the first embodiment described above, a plurality of protrusions 21 made of rubber-like elastic members are crosslinked (vulcanized) and bonded to the facing surface 20ds of the outer peripheral flange portion 20d of the slinger 20. The case was mentioned. However, the present invention is not limited to this, and as shown in FIG. 4, the protrusion 21s having the same shape as the protrusion 21 (see FIG. 3) is pressed against the facing surface 20ds of the outer peripheral side flange portion 20d of the slinger 20. It may be formed directly by processing or the like.

Further, in the above-described first embodiment, the case where the labyrinth seal is formed between the outer end surface 51b of the outer ring 51 and the slinger 20 has been described, but the present invention is not limited to this, and the outer ring 51 is not limited to this. The outer end surface 51b of the slinger 20 is covered with an elastic body portion of a sealing device, a labyrinth seal is formed between the elastic body portion and the slinger 20, and the outer peripheral side flange portion 20d of the slinger 20 arranged to face the elastic body portion faces. The protrusion 21 may be provided on the surface 20ds.

Further, in the first embodiment described above, the case where the protrusion 21 is provided on the facing surface 20ds of the outer peripheral flange portion 20d of the slinger 20 has been described, but the present invention is not limited to this. For example, as in the sealing structure 60 (see FIG. 1), the protrusion 22 having the same shape as the protrusion 21 may be directly provided on the facing surface of the hub ring 55 facing the end of the outer ring 51. The hub bearing 50 may be provided with the sealing structure 10 on the outside (direction of arrow a) and the sealing structure 60 on the inside (direction of arrow b).

In this case, the elastic body portion 6d of the sealing device 6 fixed to the inner end (direction of arrow b) of the outer ring 51 and the protrusion 22 of the hub ring 55 are arranged to face each other. As a result, it is possible to prevent foreign matter from entering through the gap between the elastic body portion 6d of the sealing device 6 and the protrusion 22 of the hub ring 55 by the air flow generated by the protrusion 22 in advance. Moreover, even if the foreign matter invades the inner peripheral side (direction of arrow d) from the protrusion 22, the foreign matter can be discharged to the outside by the air flow generated by the protrusion 22.

<Second Embodiment>
The sealing structure 70 according to the second embodiment of the present invention will be described. FIG. 5 is a cross-sectional view showing an overall schematic configuration of a sealed structure according to a second embodiment of the present invention. FIG. 6 is a partially enlarged cross-sectional view showing a labyrinth structure by the sealing device and the protrusion according to the second embodiment. FIG. 7 is a schematic perspective view showing the configuration of the protrusion according to the second embodiment. FIG. 8 is a view taken along the arrow A of the protrusion according to the second embodiment. FIG. 9 is a view taken along the line B of the protrusion according to the second embodiment. In the second embodiment, the same reference numerals are used for the constituent requirements common to those of the first embodiment, and the description of the common configuration and the effects will be omitted.

<Sealed structure>
The sealing structure 70 in the second embodiment is provided in the sealing device 7 and the slinger 80 in place of the sealing device 6 and the protrusion 22 (see FIG. 1) of the sealing structure 60 in the first embodiment. The protrusion 23 is provided. The hub bearing 50 may include the sealing structure 10 according to the first embodiment in addition to the sealing structure 70.

As shown in FIG. 6, the sealing device 7 includes a reinforcing ring 72 and an elastic body portion 74. The reinforcing ring 72 reinforces the elastic body portion 74 and is made of a metal material. The reinforcing ring 72 is manufactured by, for example, pressing or forging, and is arranged in a molding die when the elastic body portion 74 is formed by cross-linking (vulcanization) molding. In the reinforcing ring 72, the elastic body portion 74 is adhered to the reinforcing ring 72 by cross-linking, so that the elastic body portion 74 is integrally formed with the reinforcing ring 72.

The reinforcing ring 72 includes a hollow disk-shaped disk portion 72a located on the outermost side, and a cylindrical cylindrical portion 72b extending outward (arrow a direction) from an end portion on the inner peripheral side (arrow d direction) of the disk portion 72a. And the bent portion 72c that bends from the inner (arrow b direction) end of the cylindrical portion 72b and extends inward (arrow b direction), and the inner peripheral side (arrow b direction) from the inner (arrow b direction) end of the bent portion 72c. It is provided with a hollow disk-shaped disk portion 72d extending in the direction of the arrow d). Specifically, the reinforcing ring 72 is formed so that the cylindrical portion 72b is fitted to the inner peripheral surface of the outer ring 51.

The elastic body portion 74 has a base portion 75, and has an outer peripheral side lip 76, an inner peripheral side lip 77, and a radial lip 78, which are portions extending inward (in the direction of arrow b) from the base portion 75. are doing.

The outer peripheral side lip 76 and the inner peripheral side lip 77 as seal lips have their tip portions extending inward (in the direction of arrow b) and have a predetermined tightening allowance (contact width). Is in contact with the surface (hereinafter, also referred to as "outer surface") 80a on the outer side (direction of arrow a) of the slinger 80.

The radial lip 78 is located on the inner peripheral side (arrow d direction) of the inner peripheral side lip 77, and its tip extends outward (arrow a direction) and inner peripheral side (arrow d direction), and is predetermined. The tip of the slinger 80 is brought into contact with the outer surface 80a of the slinger 80 with the tightening allowance.

The slinger 80 is attached to the hub ring 55 and fixed to the outer ring 51 to a position facing the outer peripheral side (arrow c direction) end of the base portion 75 of the elastic body portion 74 of the sealing device 7. The side end 80b extends.

A plurality of protrusions 23 are indirectly provided on the facing surface of the hub ring 55 facing the inner end surface 51c of the outer ring 51 via the slinger 80. These plurality of protrusions 23 extend from the inner peripheral side (arrow d direction) to the outer peripheral side (arrow c direction) with the axis x as the center, and are arranged radially and circumferentially at predetermined intervals about the axis x. ing.

These plurality of protrusions 23 are made of various rubber-like elastic members, and are crosslinked (vulcanized) bonded to the outer peripheral side end portion 80b on the outer peripheral side (arrow c direction) of the slinger 80. Examples of the rubber-like elastic member are synthetic rubbers such as ditrill rubber (NBR), hydrogenated nitrile rubber (H-NBR), acrylic rubber (ACM), and fluororubber (FKM).

As shown in FIG. 7, the protrusion 23 is a portion of the elastic body portion 74 that protrudes outward (in the direction of arrow a) from the outer surface 80a of the outer peripheral side end portion 80b of the slinger 80 facing the base portion 75. Yes, it has a substantially trapezoidal shape in the side view.

As shown in FIGS. 8 and 9, the width of the protrusion 23 gradually increases from the inner peripheral side end surface 23d on the inner peripheral side (direction of arrow d) toward the inclined surface 23c, the ceiling surface 23b, and the outer peripheral side end surface 23e. The side surfaces 23a and 23a are formed so as to do so. That is, the protrusions 23 are formed symmetrically with respect to the outer surface 80a of the slinger 80 with the axis y as the center. Further, the protrusion 23 is formed by the inclined surface 23c so that its height gradually increases from the inner peripheral side end surface 23d toward the ceiling surface 23b.

<Foreign matter intrusion suppression operation and foreign matter discharge operation>
In such a sealing structure 70, when the slinger 80 is rotated with the rotation of the hub ring 55, the base of the elastic body portion 74 of the sealing device 7 fixed to the outer ring 51 by the plurality of protrusions 23 arranged radially. In the gap g3 (see FIG. 6) between the portion 75 and the slinger 80, an airflow Ar from the inner peripheral side (direction of arrow d) to the outer peripheral side (direction of arrow a) can be generated.

As a result, it is possible to prevent foreign matter from entering through the gap g3 between the base portion 75 of the elastic body portion 74 of the sealing device 7 and the outer peripheral side end portion 80b of the slinger 80 by the air flow Ar generated by the protrusion 23. it can. Moreover, even if the foreign matter invades the inner peripheral side (direction of arrow d) from the protrusion 23, the foreign matter can be discharged to the outside by the air flow Ar generated by the protrusion 23.

Since the protrusion 23 has a symmetrical shape about the axis y, the hub ring 55 is rotated in either the clockwise direction or the counterclockwise direction when viewed from the outside (arrow a direction). However, it is possible to generate an airflow Ar from the inner peripheral side (direction of arrow d) to the outer peripheral side (direction of arrow a) to suppress or prevent the invasion of foreign matter.

Further, since the plurality of protrusions 23 are made of rubber-like elastic members, the gap between the base portion 75 of the elastic body portion 74 of the sealing device 7 and the outer surface 80a of the slinger 80 is narrowed and sealed. Even when the property is improved and the protrusion 23 comes into contact with the base portion 75 of the elastic body portion 74, the damage to the elastic body portion 74 can be reduced.

Thus, in the hub bearing 50, it is possible to simultaneously realize the sealing structures 10 and 70 that can suppress the invasion of foreign matter and at the same time can easily discharge the once invaded foreign matter to the outside.

In the second embodiment described above, a case where a plurality of protrusions 23 made of rubber-like elastic members are crosslinked (vulcanized) and bonded to the outer surface 80a of the slinger 80 has been described. However, the present invention is not limited to this, and the protrusion 23 may be directly formed on the outer surface 80a of the slinger 80 by press working or the like.

Further, in the second embodiment described above, the case where the protrusion 23 is provided on the outer surface 80a of the slinger 80 has been described, but the present invention is not limited to this, and for example, the sealing structure 60 ( As shown in FIG. 1), the protrusion 23 may be provided directly on the facing surface of the hub ring 55 facing the end of the outer ring 51.

<Other embodiments>
Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the sealed structures 10, 60, and 70 according to the above-described embodiment, and is within the scope of the concept and claims of the present invention. Includes all aspects involved. In addition, each configuration may be selectively combined as appropriate so as to achieve at least a part of the above-mentioned problems and effects. For example, the shape, material, arrangement, size, etc. of each component in the above embodiment can be appropriately changed depending on the specific usage mode of the present invention.

The case where the sealed structure of the present invention is used in a hub bearing of an automobile has been described. However, the sealing device of the present invention is not limited to automobiles, but can be used for industrial bearings and the like.

1, 6, 7, 110 Sealing device 10, 60, 70 Sealing structure 11, 74, 112 Elastic body portion 12, 72, 111 Reinforcing ring 14, 75 Base portion 15, 113, 114 Side lip 17 Outer radial lip 19 Inner radial Lip 20, 80 Slinger 21, 21s, 22, 23 Protrusions 50, 100 Hub bearing 51, 101 Outer ring 52 Hub 54, 102 Inner ring 55 Hub wheel 56 Wheel mounting flange 57 Hub bolt 76 Outer peripheral side lip 77 Inner peripheral side lip 78 Radial lip x axis

Claims (5)

Seals between the outer peripheral side member and the inner peripheral side member of a bearing device including an annular outer peripheral side member that can rotate relative to each other with respect to the axis and an annular inner peripheral side member surrounded by the outer peripheral side member. It has a sealed structure
A sealing device attached to the outer peripheral member and
With a slinger attached to the inner peripheral side member,
The sealing device has a seal lip that comes into contact with the facing surface of the slinger arranged to face the sealing device and seals between the outer peripheral side member and the inner peripheral side member.
A labyrinth seal is formed by a gap when the sealing device attached to the outer peripheral side member or the outer peripheral side member and the slinger are arranged to face each other.
It has a plurality of protrusions that protrude from the facing surface of the slinger, extend from the inner peripheral side to the outer peripheral side about the axis, and are radially arranged at predetermined intervals.
The width of the plurality of protrusions is gradually expanded from the inner peripheral side to the outer peripheral side in a cross section orthogonal to the extending direction of the protrusions.
The protrusion has an inclined surface on the inner peripheral side, and the protruding portion is formed on the inclined surface so that its height gradually increases from the inner peripheral side toward the outer peripheral side . It has a ceiling surface that follows the inclined surface on the outer peripheral side.
A sealing structure characterized in that the protrusion is formed so that its height gradually increases toward the ceiling surface . The sealing structure according to claim 1, wherein the protrusion has a symmetrical shape such that the protrusion is cut in half along an axis along the longitudinal direction of the protrusion. Seals between the outer peripheral side member and the inner peripheral side member of a bearing device including an annular outer peripheral side member that can rotate relative to each other with respect to the axis and an annular inner peripheral side member surrounded by the outer peripheral side member. It has a sealed structure
A sealing device attached to the outer peripheral side member is provided.
The sealing device has a seal lip that contacts the facing surface of the inner peripheral side member arranged to face the sealing device and seals between the outer peripheral side member and the inner peripheral side member.
A labyrinth seal is formed by a gap when the sealing device attached to the outer peripheral side member or the outer peripheral side member and the inner peripheral side member are arranged to face each other.
It has a plurality of protrusions radially arranged at predetermined intervals, which are provided with respect to the facing surfaces of the inner peripheral side members and extend from the inner peripheral side to the outer peripheral side with the axis as the center.
The plurality of protrusions have a sealing structure in which the width thereof is gradually expanded from the inner peripheral side to the outer peripheral side. The protrusion has a pair of side surfaces connected via the inclined surface and the ceiling surface in the circumferential direction.
Each of the pair of side surfaces extends from the facing surface and is connected to the inclined surface and the ceiling surface, and is inclined toward the inclined surface and the ceiling surface side with respect to the facing surface.
Width of the pair of side surfaces, the sealing structure according to claim 1, characterized in that from the inner circumference side are gradually expands toward the outer peripheral side. The sealing structure according to claim 1, wherein the protruding portion protrudes from the facing surface so as to have an outer shape such that a bullet is cut in half.

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