WO2018074543A1

WO2018074543A1 - Bearing device for wheels

Info

Publication number: WO2018074543A1
Application number: PCT/JP2017/037820
Authority: WO
Inventors: 峻介森田
Original assignee: Ntn株式会社
Priority date: 2016-10-20
Filing date: 2017-10-19
Publication date: 2018-04-26
Also published as: JP2018066448A

Abstract

Provided is a bearing device for wheels, which has improved sealing properties obtained without an increase in rotational torque. This bearing device 1 for wheels is provided with: an outer ring 2 serving as an outer member; a hub ring 3 serving as an inner member; at least one inner ring 4 press-fitted in the hub ring 3; rolling bodies 5 contained in a rollable manner between the respective rolling surfaces of the inner member and the outer member; and a seal member 6 having a seal lip provided to a seal plate 7 comprising a fitting section 7a and an inner diameter section 7b which extends radially inward from an end of the fitting section 7a, the seal lip being in contact with a slinger 8 to provide sealing between the outer ring 2 and the inner ring 4, the slinger 8 comprising a circular cylinder section 8a and a vertical plate section 8b. A cylindrical flange section 8d extending from the vertical plate section 8b toward the seal plate 7 is formed on the vertical plate section 8b, and the flange section 8d is formed such that the inner diameter thereof increases from the vertical plate section 8b side toward the front end section side. The fitting section 7a is formed such that the inner diameter thereof increases from the inner diameter section 7b side toward the front end side.

Description

Wheel bearing device

The present invention relates to a wheel bearing device. Specifically, the present invention relates to a wheel bearing device including a seal member that forms a labyrinth.

Conventionally, a wheel bearing device that supports a wheel rotatably in a suspension device of an automobile or the like is known. In a wheel bearing device, a hub wheel (inner member) connected to a wheel is rotatably supported by an outer member via a rolling element. The bearing device for a wheel shortens the bearing life by damaging the rolling elements and the raceway surface by reducing internal grease or rainwater or dust. For this reason, in the wheel bearing device, a seal member is provided between the outer member and the inner member in order to prevent leakage of grease enclosed therein and to prevent rainwater and dust from entering from the outside. Is provided.

In such a wheel bearing device, in order to obtain a longer bearing life, a seal member is provided with a plurality of seal mechanisms to improve the sealing performance. With this configuration, the pack seal can suppress rainwater and dust from entering the tip of the seal lip due to the labyrinth, prevent damage to the tip of the seal lip, and improve the sealing performance. For example, as described in Patent Document 1.

The wheel bearing device described in Patent Document 1 includes a cylindrical outer member, an inner ring constituting the inner member, a rolling element that rotatably supports the inner ring, and a seal member that seals the opening. To do. The seal member is composed of a pack seal in which a seal plate fitted to the outer member and a slinger fitted to the inner ring are arranged to face each other. The slinger is formed with a flange portion that is bent in a cylindrical shape in the axial direction from the standing plate portion. The labyrinth is configured by the slinging portion of the sealing member facing the sealing plate via a slight radial gap. The seal member is provided with a plurality of seal lips so that muddy water or the like that has passed through the non-contact labyrinth does not enter the inside of the bearing device.

In addition to the two side lips (axial lip) that are in contact with the slinger's vertical plate, the grease lip (radial lip) that is in contact with the cylindrical portion of the slinger, the seal member is slightly between the slinger's buttocks. An auxiliary lip that constitutes the labyrinth is provided through a gap. As described above, the wheel bearing device is configured so that the sealing performance is improved by the plurality of lips so that muddy water or the like that has passed through the labyrinth does not enter the inside of the bearing device. However, the seal member described in Patent Document 1 has an increased rotational torque of the seal because a plurality of seal lips come into contact with the slinger. Further, when muddy water or the like enters the seal member, the muddy water or the like is hardly discharged to the outside due to the complicated structure of the seal lip. For this reason, the technique described in Patent Document 1 complicates the internal structure of the seal member and prevents rotation of the seal so that muddy water or the like that passes through the non-contact labyrinth and enters the seal member does not enter the bearing. It was disadvantageous in that the torque increased.

JP 2015-110958 A

The present invention has been made in view of the above situation, and an object thereof is to provide a wheel bearing device capable of improving the sealing performance without increasing the rotational torque.

That is, in the wheel bearing device, an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, a hub wheel in which a small-diameter step portion extending in the axial direction is formed on the outer periphery, and the small-diameter step An inner member formed of at least one inner ring press-fitted into a portion and having an outer peripheral surface formed with a double row inner raceway facing the double row outer raceway, and the inner raceway and the outer raceway. A seal plate comprising a double row rolling element accommodated between the running surface so as to be freely rollable, and a fitting portion and an inner diameter portion extending radially inward from the end portion thereof, the inner diameter portion serving as the outer member. A slinger comprising a cylindrical portion and a standing plate portion extending radially outward from an end portion thereof is fitted into the opening of the outer member toward the inside of the outer member. The cylindrical portion is fitted to the outer peripheral portion of the inner member, arranged closer to the opening than the inner diameter portion, At least one seal lip made of an elastic body is provided at a portion, and the seal lip seals between the outer member and the inner member by contacting the slinger. In the bearing device, a cylindrical flange portion extending from the standing plate portion toward the seal plate is formed on the standing plate portion, and an inner diameter of the flange portion increases as it goes from the standing plate portion side to the tip portion side. The fitting portion is formed so that the inner diameter of the fitting portion increases from the inner diameter portion side toward the distal end portion side. Here, it is assumed that the inner diameter of the fitting portion includes an elastic member bonded by vulcanization.

In the wheel bearing device, the labyrinth is configured by bringing the outer peripheral surface of the flange portion close to the inner peripheral surface of the fitting portion.

In the wheel bearing device, the seal lip is composed of a radial lip that is in contact with the cylindrical portion and an axial lip that is in contact with the upright plate portion.

In the wheel bearing device, a labyrinth slip that extends from the seal plate toward the slinger is formed on the outer side in the radial direction than the axial lip, and the labyrinth is configured by bringing the labyrin slip close to the slinger. .

In the wheel bearing device, a labyrinth slip extending from the seal plate toward the slinger is formed radially inward of the axial lip, and the labyrinth is configured by bringing the labyrin slip close to the slinger. .

As the effects of the present invention, the following effects are obtained.

That is, according to the present invention, since the inner peripheral surface of the slinger flange and the inner peripheral surface of the fitting portion of the seal plate are formed on the inclined surface, mud water or the like that has entered the seal member is caused by centrifugal force. It is discharged to the outside along the inner peripheral surface of the flange portion and the inner peripheral surface of the cylindrical portion. Thereby, the sealing performance can be improved without increasing the rotational torque.

According to the present invention, entry of muddy water or the like is suppressed by the non-contact labyrinth, and muddy water or the like that has passed through the labyrinth is discharged to the outside by centrifugal force. It is discharged outside by an annular groove. Thereby, the sealing performance can be improved without increasing the rotational torque.

According to the present invention, since the sealing performance is improved by the non-contact labyrinth, the intrusion of muddy water or the like is prevented between the axial lip and the radial lip. Thereby, the sealing performance can be improved without increasing the rotational torque.

According to the present invention, it is difficult for muddy water or the like to reach the lip seal by further providing a labyrinth in the vicinity of the seal lip using the shape of the slinger. Thereby, the sealing performance can be improved without increasing the rotational torque.

The perspective view which shows the whole structure in 1st embodiment of the wheel bearing apparatus which concerns on this invention. Sectional drawing which shows the whole structure in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows the structure of the seal member in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows a state when muddy water etc. enter into the sealing member in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows the state in which muddy water etc. are discharged | emitted from the sealing member in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows the sealing member in 2nd embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows the seal member in 3rd embodiment of the wheel bearing apparatus which concerns on this invention.

Hereinafter, the wheel bearing device 1 which is the first embodiment of the wheel bearing device according to the present invention will be described with reference to FIGS. 1 to 3.

As shown in FIG. 1 and FIG. 2, the wheel bearing device 1 supports a wheel rotatably in a suspension device of a vehicle such as an automobile. The wheel bearing device 1 includes an outer ring 2 that is an outer member, a hub ring 3 that is an inner member, an inner ring 4, two rows of inner side balls 5a (see FIG. 2) that are rolling rows, and an outer side ball row. 5b (refer FIG. 2), the inner side sealing member 6, and the outer side sealing member 9 (refer FIG. 2) are comprised.

As shown in FIG. 2, the outer ring 2 which is an outer member supports the hub ring 3 (the hub ring 3 and the inner ring 4). The outer ring 2 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C formed in a substantially cylindrical shape. In the outer ring 2, an inner side opening 2 a into which the inner side seal member 6 can be fitted is formed at the inner side end of the outer ring 2 arranged on the vehicle body side when the vehicle is mounted. In the outer ring 2, an outer side opening 2 b into which the outer side seal member 9 can be fitted is formed at an outer side end disposed on the wheel side when the vehicle is mounted. Here, the inner side represents the vehicle body side of the wheel bearing device 1 when attached to the vehicle body, and the outer side represents the wheel side of the wheel bearing device 1 when attached to the vehicle body.

On the inner peripheral surface of the outer ring 2, an annular inner side outer rolling surface 2 c and an outer side outer rolling surface 2 d are formed so as to be parallel to each other in the circumferential direction. The outer rolling surface 2d on the outer side is formed so that the inner side outer rolling surface 2c and the pitch circle diameter are equal or larger. A hardened layer having a surface hardness in the range of 58 to 64 HRC is formed by induction hardening on the outer side rolling surface 2c on the inner side and the outer side rolling surface 2d on the outer side. On the outer peripheral surface of the outer ring 2, a vehicle body attachment flange 2e for attaching to a knuckle of a suspension device (not shown) is integrally formed in the vicinity of the inner side opening 2a.

The hub wheel 3 constituting the inward member rotatably supports a vehicle wheel (not shown). The hub ring 3 is made of medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C formed in a bottomed cylindrical shape. In the hub wheel 3, a small-diameter step portion 3a having a reduced diameter on the outer peripheral surface is formed at an inner side end portion disposed on the vehicle body side when the vehicle is mounted. In the hub wheel 3, a wheel mounting flange 3 b for mounting a wheel is integrally formed at an outer side end disposed on the wheel side when the vehicle is mounted. The wheel mounting flange 3b is provided with hub bolts 3d at equal circumferential positions. The hub wheel 3 is disposed such that the inner rolling surface 3 c formed on the outer side faces the outer rolling surface 2 d on the outer side of the outer ring 2.

The hub wheel 3 is hardened to a surface hardness of 58 to 64 HRC by induction quenching from the inner-side small-diameter step portion 3a to the outer-side inner rolling surface 3c to the lip contact surface of the seal 9. Thereby, the hub wheel 3 has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 3b, and the durability of the hub wheel 3 is improved. The hub wheel 3 is provided with an inner ring 4 at a small diameter step portion 3a. The hub race 3 has an inner raceway surface 4c formed on the outer side with an inner raceway surface 4a formed on the inner race 4 at the inner end facing the outer raceway surface 2c on the inner side of the outer race 2. Is arranged so as to face the outer rolling surface 2d on the outer side of the outer ring 2.

The inner ring 4 is a rolling train that preloads the inner side ball row 5a disposed on the vehicle body side when mounted on the vehicle and the outer side ball row 5b disposed on the wheel side when mounted on the vehicle side. The inner ring 4 is formed in a cylindrical shape. The inner ring 4 is made of a high carbon chrome bearing steel such as SUJ2, and is hardened in the range of 58 to 64 HRC to the core part by quenching. On the outer peripheral surface of the inner ring 4, an annular inner rolling surface 4a is formed in the circumferential direction. The inner ring 4 is integrally fixed to the inner side end portion of the hub wheel 3 by caulking while a predetermined preload is applied by press fitting. That is, the inner raceway 4 a is formed by the inner race 4 on the inner side of the hub race 3. The hub race 3 has an inner raceway surface 4c formed on the outer side with an inner raceway surface 4a formed on the inner race 4 at the inner end facing the outer raceway surface 2c on the inner side of the outer race 2. Is arranged so as to face the outer rolling surface 2d of the outer ring 2 on the outer side.

The inner side ball row 5a and the outer side ball row 5b, which are rolling rows, support the hub wheel 3 rotatably. In the inner side ball row 5a and the outer side ball row 5b, a plurality of balls, which are rolling elements, are held in an annular shape by a cage. The inner side ball row 5a and the outer side ball row 5b are made of a high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC up to the core by quenching. The inner side ball row 5a is sandwiched between an inner rolling surface 4a formed on the inner ring 4 and an outer rolling surface 2c on the inner side of the outer ring 2 facing the inner rolling surface 4a. The outer side ball row 5b is sandwiched between the inner rolling surface 3c formed on the hub wheel 3 and the outer side rolling surface 2d on the outer side of the outer ring 2 facing the outer rolling surface 3c. . That is, the inner side ball row 5 a and the outer side ball row 5 b support the hub wheel 3 and the inner ring 4 so as to be rotatable with respect to the outer ring 2.

The wheel bearing device 1 includes a double row angular ball bearing composed of an outer ring 2, a hub ring 3, an inner ring 4, an inner side ball row 5a, and an outer side ball row 5b. In the present embodiment, the wheel bearing device 1 is configured with a double-row angular contact ball bearing, but is not limited thereto, and may be configured with a double-row tapered roller bearing or the like.

As shown in FIGS. 2 and 3, the inner side sealing member 6 closes the gap between the inner side opening 2 a of the outer ring 2 and the hub ring 3. The inner side sealing member 6 includes a substantially cylindrical sealing plate 7 and a substantially cylindrical slinger 8.

As shown in FIG. 3, the seal plate 7 is composed of a core metal and a seal lip. The core metal is made of a ferritic stainless steel plate (JIS standard SUS430 or the like), an austenitic stainless steel plate (JIS standard SUS304 or the like), or a rust-proof cold-rolled steel plate (JIS standard SPCC system or the like). It is configured. The core metal is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion of an annular steel plate by press working. As a result, the cored bar is configured with a fitting portion 7 a that can be fitted into the inner side opening 2 a of the outer ring 2 and an annular inner diameter portion 7 b that extends from the end portion toward the axial center. A seal material, which is an elastic member, is vulcanized and bonded to a part of the outer peripheral surface of the fitting portion 7a fitted into the inner side opening 2a. A radial lip 7c (grease lip) and an axial lip 7d (side lip) are integrally vulcanized and bonded to one side surface of the inner diameter portion 7b. Radial lip 7c and axial lip 7d are NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile-butadiene rubber), EPDM (ethylene propylene rubber), ACM with excellent heat resistance and chemical resistance. (Polyacrylic rubber), FKM (fluoro rubber), or synthetic rubber such as silicon rubber. The seal plate 7 has a fitting portion 7 a fitted into the inner side opening 2 a of the outer ring 2 with the inner diameter portion 7 b facing the inner side (outer side) of the outer ring 2.

The slinger 8 is composed of a steel plate equivalent to the seal plate 7. The slinger 8 is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion and an inner edge portion of an annular steel plate by press working. Thus, the slinger 8 includes a cylindrical portion 8a that can be fitted to the outer peripheral surface of the inner ring 4, and an annular vertical plate portion 8b that extends radially outward from the end of the cylindrical portion 8a. In the slinger 8, the cylindrical portion 8 a is fitted to the outer periphery of the inner ring 4 with the standing plate portion 8 b facing the outer side (inner side) of the outer ring 2. The slinger 8 is fixed to the inner ring 4 at a position outside the outer ring 2 relative to the seal plate 7. At this time, the slinger 8 is disposed so that the inner side surface (outer side surface) of the upright plate portion 8 b faces the outer side surface (inner side surface) of the inner diameter portion 7 b of the seal plate 7. Further, the standing plate portion 8 b is formed to have an outer diameter smaller than the inner diameter of the fitting portion 7 a of the seal plate 7. That is, the standing plate portion 8b is disposed inside the fitting portion 7a. A magnetic encoder 8c is provided on the outer surface of the upright plate portion 8b.

Thus, the inner side seal member 6 is disposed so that the seal plate 7 fitted to the inner side opening 2a of the outer ring 2 and the slinger 8 fitted to the inner ring 4 face each other, thereby constituting a pack seal. is doing. The radial lip 7c of the seal plate 7 is in contact with the cylindrical portion 8a of the slinger 8 through an oil film, thereby preventing leakage of grease inside the wheel bearing device 1 to the outside. The axial lip 7d of the seal plate 7 is in contact with the standing plate portion 8b of the slinger 8 via an oil film, and prevents the muddy water or the like from entering from the outside of the wheel bearing device 1. The inner side seal member 6 is configured to be slidable with respect to the slinger 8 when the radial lip 7c and the axial lip 7d of the seal plate 7 contact the slinger 8 through an oil film. Thereby, the inner side sealing member 6 prevents the leakage of the lubricating grease from the inner side opening 2a of the outer ring 2 and the entry of rainwater, dust and the like from the outside.

As shown in FIG. 2, the outer side sealing member 9 closes the gap between the outer side opening 2 b of the outer ring 2 and the hub ring 3. The outer side seal member 9 is configured as an integral seal in which a seal lip is vulcanized and bonded to a substantially cylindrical cored bar.

The core of the outer side seal member 9 is made of a ferritic stainless steel plate (JIS standard SUS430 or the like), an austenitic stainless steel plate (JIS standard SUS304 or the like), or a rust-proof cold rolled steel plate (JIS standard). SPCC system etc.). The core metal is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion of an annular steel plate by press working. The seal lip is NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile butadiene rubber) with excellent heat resistance, EPDM (ethylene propylene rubber), ACM (polyacrylic rubber) with excellent heat resistance and chemical resistance, It is made of synthetic rubber such as FKM (fluoro rubber) or silicon rubber.

The outer side seal member 9 has a core metal fitted into the outer side opening 2b of the outer ring 2. At this time, the outer side seal member 9 is arranged so that the seal lip contacts the seal sliding surface of the hub wheel 3. The outer side seal member 9 is configured to be slidable with respect to the seal sliding surface when the seal lip contacts the seal sliding surface of the hub wheel 3 through the oil film. Thereby, the seal lip of the outer side seal member 9 prevents leakage of lubricating grease from the outer side opening 2b of the outer ring 2 and entry of rainwater, dust, and the like from the outside.

The wheel bearing device 1 configured as described above includes an outer ring 2, a hub ring 3, an inner ring 4, an inner side ball row 5a, and an outer side ball row 5b to form a double row angular ball bearing. 4 is rotatably supported by the outer ring 2 via an inner side ball row 5a and an outer side ball row 5b. In the wheel bearing device 1, the gap between the inner side opening 2 a of the outer ring 2 and the inner ring 4 is closed by the inner side seal member 6, and the gap between the outer side opening 2 b of the outer ring 2 and the hub ring 3 is closed. The outer side sealing member 9 is closed. As a result, in the wheel bearing device 1, the hub ring 3 and the inner ring 4 supported by the outer ring 2 rotate while preventing leakage of lubricating grease from the inside and entry of rainwater, dust, and the like from the outside.

Next, the seal plate 7 and the slinger 8 constituting the inner side seal member 6 will be described in detail with reference to FIGS.
As shown in FIGS. 3 and 4, the seal plate 7 includes a fitting portion 7 a fitted into the outer ring 2, and an annular inner diameter portion 7 b extending radially inward from the end portion of the fitting portion 7 a. It is composed of The slinger 8 includes a cylindrical portion 8a fitted into the inner ring 4 and an annular standing plate portion 8b extending radially outward from the end of the cylindrical portion 8a. The inner side seal member 6 is disposed so that the inner diameter portion 7b of the seal plate 7 and the standing plate portion 8b of the slinger 8 face each other.

The fitting part 7 a of the seal plate 7 is fitted into the inner side opening 2 a of the outer ring 2 with the inner diameter part 7 b facing the inner side of the outer ring 2. That is, the outer peripheral surface of the fitting portion 7a is formed in a cylindrical shape having an outer diameter that allows the cored bar to be fitted into the inner side opening 2a. The inner peripheral surface of the fitting portion 7 a is formed so that the inner diameter becomes larger toward the outer side of the outer ring 2. That is, the inner peripheral surface of the fitting portion 7a has a diameter from the inner side of the outer ring 2 that is the base end side (outer side) to which the inner diameter portion 7b is connected to the outer side of the outer ring 2 that is the distal end side (inner side). A resin for forming a seal lip (a dark thin ink portion) covers the mandrel so as to incline outward in the direction at an angle θ1 (see FIG. 4).

A flange 8d is formed at the radial end (outer end) of the standing plate 8b of the slinger 8. The flange portion 8d is a cylinder that extends a predetermined amount in the axial direction from the radial end portion of the upright plate portion 8b having an outer diameter smaller than the inner diameter of the fitting portion 7a of the seal plate 7 toward the inner side (outer side) of the outer ring 2. It is formed in a shape. That is, the flange portion 8d is formed in a cylindrical shape having a predetermined height, and is disposed inside the fitting portion 7a. In the present embodiment, the flange portion 8d is formed integrally with the standing plate portion 8b by bending the end portion in the radial direction of the standing plate portion 8b toward the inside of the outer ring 2 in a cylindrical shape. The inner peripheral surface of the flange portion 8d is formed so that the inner diameter becomes larger toward the inner side of the outer ring 2. That is, the inner peripheral surface of the flange portion 8d has a diameter from the outer side of the outer ring 2 on the base end side (inner side) connected to the upright plate portion 8b toward the inner side of the outer ring 2 on the distal end side (outer side). It is formed to incline at an angle θ2 outward in the direction (see FIG. 4). On the other hand, the outer peripheral surface of the flange portion 8d is formed to have the same outer diameter from the proximal end to the distal end. That is, the outer peripheral surface of the flange portion 8d is covered with the resin (thin thin ink portion) constituting the magnetic encoder 8c so as to have the same outer diameter from the proximal end to the distal end.

The flange portion 8d of the slinger 8 is disposed so as to overlap at least the tip portion of the axial lip 7d of the seal plate 7 in the radial direction. That is, the slinger 8 is disposed so as to cover the axial lip 7d by the cylindrical portion 8a, the standing plate portion 8b, and the flange portion 8d. Further, the flange portion 8d is disposed inside the fitting portion 7a so that at least a part thereof overlaps with the fitting portion 7a of the seal plate 7 when viewed in the radial direction. The flange portion 8d is formed so that its outer peripheral surface is close to the inner peripheral surface of the fitting portion 7a with a slight gap. Further, the flange portion 8d is formed so that the front end surface thereof is close to the outer surface (side surface on the inner side) of the inner diameter portion 7b of the seal plate 7 with a slight gap. Thereby, the inner side seal member 6 has a labyrinth 10 between the inner peripheral surface of the fitting portion 7a and the outer peripheral surface of the flange portion 8d, and between the outer surface of the inner diameter portion 7b and the front end surface of the flange portion 8d. Is configured continuously.

By configuring in this way, the inner side seal member 6 of the wheel bearing device 1 allows the muddy water or the like that has entered the vicinity of the axial lip 7d to be subjected to the centrifugal force due to the rotation of the slinger 8 and the inclination of the inner peripheral surface of the flange 8d. As a result, a force for discharging toward the fitting portion 7a of the seal plate 7 is generated. Further, in the inner side seal member 6, muddy water or the like discharged to the inner peripheral surface of the fitting portion 7a is easily discharged to the outside of the inner side seal member 6 due to the inclination of the inner peripheral surface of the fitting portion 7a. Further, the inner side seal member 6 has muddy water or the like formed by a labyrinth 10 formed between the inner diameter portion 7b and the distal end surface of the flange portion 8d and between the inner peripheral surface of the fitting portion 7a and the flange portion 8d. Hard to get inside.

Therefore, as shown in FIG. 4, the labyrinth 10 of the inner side seal member 6 is inhibited from entering muddy water or the like (see W in FIG. 4) (see black arrows).
Further, as shown in FIG. 5, centrifugal force (see arrow C <b> 0) acts on the muddy water or the like (see W in FIG. 5) that has entered the inner side seal member 6 due to the rotation of the slinger 8, so It is pressed by the inner peripheral surface of the collar part 8d formed in this. Muddy water or the like pressed against the inner peripheral surface of the inclined flange portion 8d is discharged toward the inner peripheral surface of the fitting portion 7a by the component force in the slope direction of the centrifugal force (see arrow C1) (black). (See painted arrow). The muddy water or the like discharged to the inner peripheral surface of the fitting portion 7a is discharged to the outside of the inner side seal member 6 by the discharging action due to the inclination of the fitting portion 7a. Thereby, the wheel bearing device 1 can improve the sealing performance without increasing the rotational torque.

Next, a wheel bearing device 11 which is a second embodiment of the wheel bearing device according to the present invention will be described with reference to FIG. In addition, the

wheel bearing devices

11 and 13 according to the following embodiments are used in the description as being applied in place of the wheel bearing device 1 in the wheel bearing device 1 shown in FIGS. 1 to 5. By using names, figure numbers, and symbols, the same thing is pointed out, and in the following embodiments, specific explanations are omitted with respect to the same points as the embodiments already described, and different parts are mainly described. To do.

As shown in FIG. 6, a radial lip 7c, an axial lip 7d, and a labyrin slip 7e are integrally vulcanized and bonded to one side surface of the inner diameter portion 7b of the seal plate 7. The seal plate 7 is configured integrally with the outer ring 2 by fitting the fitting part 7 a into the inner side opening 2 a of the outer ring 2. The labyrinth slip 7e of the seal plate 7 constitutes the labyrinth 12 without contacting the slinger 8 and prevents the muddy water or the like from entering from the outside of the wheel bearing device 11. The labyrinth slip 7e is disposed on the outer side in the radial direction than the axial lip 7d, and is formed so as to be close to the slinger 8 from the seal plate 7. The labyrinth slip 7e is formed so as to be close to the standing plate portion 8b or the flange portion 8d of the slinger 8 with a slight gap between the labyrinth slip 7e. That is, the labyrinth slip 7e constitutes the labyrinth 12 by being close to the standing plate portion 8b or the flange portion 8d of the slinger 8.

By configuring in this way, the inner seal member 6 of the wheel bearing device 11 is provided between the inner diameter portion 7b and the distal end surface of the flange portion 8d, and the inner peripheral surface of the fitting portion 7a and the flange portion 8d. Due to the labyrinth 10 formed between the muddy water and the like, it is difficult for muddy water or the like to enter. Furthermore, muddy water or the like is unlikely to enter the inner side sealing member 6 to the sealing position by the axial lip 7d by the labyrinth 12 formed between the labyrinth slip 7e and the flange portion 8d. Therefore, the inner side seal member 6 is prevented from entering muddy water or the like by the labyrinth 10 and the labyrinth 12. Moreover, the inner side seal member 6 is arrange | positioned so that the labyrinth slip 7e may overlap with the collar part 8d by radial direction view. That is, the labyrinth slip 7e is disposed so as to cover the axial lip 7d. The inner side sealing member 6 is excluded by the labyrinth slip 7e even if muddy water or the like enters the inside. Thereby, the wheel bearing device 11 can improve the sealing performance without increasing the rotational torque.

Next, a wheel bearing device 13 that is a third embodiment of the wheel bearing device according to the present invention will be described with reference to FIG.

As shown in FIG. 6, a radial lip 7c, an axial lip 7d, and a labyrin slip 7f are integrally vulcanized and bonded to one side surface of the inner diameter portion 7b of the seal plate 7. The seal plate 7 is configured integrally with the outer ring 2 by fitting the fitting part 7 a into the inner side opening 2 a of the outer ring 2. The labyrinth slip 7 f of the seal plate 7 constitutes the labyrinth 14 without contacting the slinger 8 and prevents the muddy water or the like from entering from the outside of the wheel bearing device 13. The labyrinth slip 7 f is disposed radially inward of the axial lip 7 d and is formed so as to be close to the slinger 8 from the seal plate 7. The labyrinth slip 7f is formed so as to be close to the standing plate portion 8b or the flange portion 8d of the slinger 8 with a slight gap between the labyrinth slip 7f. That is, the labyrinth slip 7 f constitutes the labyrinth 14 by being close to the standing plate portion 8 b or the flange portion 8 d of the slinger 8.

By configuring in this way, the inner seal member 6 of the wheel bearing device 13 has a space between the inner diameter portion 7b and the distal end surface of the flange portion 8d, and an inner peripheral surface of the fitting portion 7a and the flange portion 8d. Due to the labyrinth 10 formed between the muddy water and the like, it is difficult for muddy water or the like to enter. Furthermore, muddy water or the like is unlikely to enter the inner seal member 6 up to the seal position by the radial lip 7c by the labyrinth 14 formed between the labyrin slip 7f and the flange portion 8d. The inner side seal member 6 is prevented from entering the inside of the wheel bearing device 13 such as muddy water by the labyrinth 10 and the labyrinth 14. Thereby, the wheel bearing device 13 can improve the sealing performance without increasing the rotational torque.

The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including. In the present embodiment, the

wheel bearing devices

1, 11, and 13 have a third generation wheel bearing device in which the inner raceway surface 3 c of the inner side ball row 5 a is directly formed on the outer periphery of the hub wheel 3. However, the present invention is not limited to this, and a second generation structure in which a pair of inner rings are press-fitted and fixed to the hub wheel 3 or a first generation structure may be used.

The present invention can be used for a wheel bearing device.

DESCRIPTION OF SYMBOLS 1 Wheel bearing apparatus 2 Outer ring 2a Inner side opening 3 Hub ring 4 Inner ring 5a Inner side ball row 5b Outer side ball row 6 Seal member 7 Seal plate 7a Fitting portion 7b Inner diameter portion 8 Slinger 8a Cylindrical portion 8b Standing plate portion 8c Magnetic encoder 8d

Claims

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
A hub wheel having a small-diameter step portion extending in the axial direction on the outer periphery and at least one inner ring press-fitted into the small-diameter step portion, the outer periphery of the double row facing the outer rolling surface of the double row on the outer periphery. An inner member formed with a running surface;
A double row rolling element accommodated movably between the inner rolling surface and the outer rolling surface;
A seal plate including a fitting portion and an inner diameter portion extending radially inward from the end portion thereof is fitted to the opening portion of the outer member with the inner diameter portion facing the inner side of the outer member. Combined
A slinger composed of a cylindrical portion and a standing plate portion extending radially outward from the end portion thereof is arranged on the opening portion side of the inner diameter portion with the standing plate portion being disposed on the outer peripheral portion of the inner member. Part is mated,
At least one seal lip made of an elastic body is provided on the inner diameter portion, and the seal lip seals between the outer member and the inner member by contacting the slinger. In the wheel bearing device,
A cylindrical flange extending from the standing plate toward the seal plate is formed on the standing plate, and an inner diameter of the flange is formed so as to increase from the standing plate to the tip. ,
The wheel bearing apparatus formed so that the internal diameter of the said fitting part may become large as it goes to the front end part side from the said internal diameter part side.
The wheel bearing device according to claim 1, wherein a labyrinth is configured by bringing the outer peripheral surface of the flange portion close to the inner peripheral surface of the fitting portion.
The wheel bearing device according to claim 2, wherein the seal lip includes a radial lip in contact with the cylindrical portion and an axial lip in contact with the standing plate portion.
4. The labyrinth according to claim 2, wherein a labyrinth slip extending from the seal plate toward the slinger is formed radially outward from the axial lip, and the labyrinth is configured by bringing the labyrin slip close to the slinger. Wheel bearing device.
4. The labyrinth according to claim 2, wherein a labyrinth slip that extends from the seal plate toward the slinger is formed radially inward of the axial lip, and the labyrinth is configured by bringing the labyrin slip close to the slinger. Wheel bearing device.