JP2017160960A - Wheel bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wheel bearing device capable of improving durability performance against slurry.SOLUTION: This invention relates to a wheel bearing device rotatably supporting a wheel in which an outer seal mechanism 10 comprises a first seal part 11, a second seal part 14 and a slinger 17. The second seal part 14 has a second side lip part 16a fitted to an outer peripheral part of an outer member 2 and protruded toward a hub ring 4. The second side lip part 16a is arranged while forming a predetermined clearance against a slant part 4o along the slant part 4o of the hub ring 4, a first labyrinth R1 is constituted by the second side lip part 16a and the slant part 4o. The slinger 17 is placed at an outer space side of an annular space to have a first gutter part 19a opened toward the outer space side of the annular space at a clearance between the slinger 17 and an inner member and a second labyrinth R2 is constituted by the slinger 17 and the second side lip part 16a.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a wheel bearing device.

  2. Description of the Related Art Conventionally, a wheel bearing device that supports a wheel rotatably is known as a suspension device for an automobile or the like. In the wheel bearing device, a hub wheel (inner member) connected to the wheel is rotatably supported by the outer member via a rolling element.

  In the wheel bearing device, the grease inside the outer member is reduced, or rainwater and dust enter, so that the rolling surface of the rolling element or the inner member is damaged and the life of the wheel bearing device is shortened. . For this reason, the wheel bearing device has an annular space between the outer member and the inner member in order to prevent leakage of grease sealed inside and prevent rainwater or dust from entering from the outside. A sealing mechanism is provided. Sealing mechanisms are respectively provided on the outer side and the inner side of the annular space (for example, Patent Document 1).

JP 2013-32823 A

  In the sealing mechanism disclosed in Patent Document 1, muddy water transmitted from the outer ring is prevented by the weir portion of the second seal portion. When the muddy water exceeds the weir, the muddy water entering the inside of the bearing is prevented by a labyrinth constituted by the second seal member of the second seal portion and the inclined portion of the wheel mounting flange.

  However, when the muddy water exceeds the labyrinth, the muddy water directly touches the tip of the side lip portion of the first seal portion, so that the tip of the side lip portion deteriorates and reduces the tightening force of the side lip portion. As a result, the muddy water may further enter the bearing and damage the bearing.

  In addition, rust may be generated at the inclined portion of the wheel mounting flange due to the intrusion of muddy water. The generated rust enters the inside of the bearing and touches the side lip tip, so that the side lip tip wears and the tightening force of the side lip decreases. As a result, the muddy water may further enter the bearing and damage the bearing.

  Then, the objective of this invention is providing the wheel bearing apparatus which can improve the durability performance and rust prevention performance with respect to muddy water.

  That is, in this invention, it is a wheel bearing device which supports a wheel rotatably, Comprising: The outer member in which an outer side rolling surface is formed in an inner peripheral side, and an inner side rolling surface is formed in an outer peripheral side. And an inner member inserted into the outer member, a rolling element movably interposed between the outer rolling surface and the inner rolling surface, the outer member and the inner member, Each sealing mechanism for sealing an annular space formed between the both sides of the wheel bearing device, and the inner member includes a hub ring and an inner ring, The outer-side seal mechanism includes a first seal portion, a second seal portion, and a slinger, wherein the slinger is disposed along an outer peripheral portion of the inner member, and the first seal portion is Fitted to the inner periphery of the outer member and formed in order from the inside to the outside of the annular space. A radial lip portion, a dust lip portion, and a first side lip portion, and the second seal portion is fitted to an outer peripheral portion of the outer member and protrudes toward the hub wheel. Two side lip portions, the second side lip portion is arranged to form a predetermined gap with respect to the hub wheel, and the second side lip portion and the hub wheel constitute a first labyrinth, The slinger is on the outer space side of the annular space, and constitutes a second labyrinth with the slinger and the second side lip portion or the outer end surface of the outer member.

  In the present invention, the slinger includes a first flange formed in a gap between the slinger and the inner member and opening toward the outer space side of the annular space, and the first seal portion. A second collar portion that opens toward the outer space side of the annular space is provided on the outer space side of the annular space, and the radial lip portion faces the inner side of the annular space and the inner side in the radial direction. The dust lip is extended toward the outer space side of the annular space and toward the inner side in the radial direction, slidably contacted with the slinger, and The side lip portion extends toward the outer space side of the annular space and toward the outer side in the radial direction, and is disposed with a predetermined gap with respect to the slinger.

  In the present invention, the first seal portion is provided with a second flange portion that opens toward the outer space side of the annular space on the outer space side of the annular space than the first side lip portion, The radial lip portion extends toward the inner side of the annular space and the inner side in the radial direction, and is in sliding contact with the slinger, and the dust lip portion is disposed on the outer space side of the annular space and in the radial direction. The first side lip portion extends toward the outer space side of the annular space and toward the outer side in the radial direction, and is in contact with the slinger. It is in sliding contact.

  According to the wheel bearing device of the present invention, even if the muddy water exceeds the first labyrinth constituted by the second side lip portion and the inclined portion of the second seal portion, the first rod provided on the slinger. The part receives muddy water, and the muddy water received by the first flange can be discharged to the outside during rotation of the bearing.

  Further, according to the wheel bearing device of the present invention, the muddy water performance can be improved by the second labyrinth constituted by the slinger and the second side lip portion of the second seal portion.

  Furthermore, according to the wheel bearing device of the present invention, even if the muddy water intrudes beyond the second labyrinth, the second heel portion provided in the slinger receives the muddy water and the muddy water received by the second heel portion. It can be discharged to the outside during rotation of the bearing. At the same time, muddy water does not directly contact the tip of the first side lip portion of the first seal portion, and deterioration of the tip of the first side lip portion can be prevented.

  Further, according to the wheel bearing device of the present invention, the waste in the muddy water that prevents the large dirt in the infiltrated muddy water by the first labyrinth and prevents the small dirt in the infiltrated muddy water by the second labyrinth, The muddy water performance can be improved by the labyrinth structure that is separated and prevented by the difference in size.

  Furthermore, according to the wheel bearing device of the present invention, the rust preventive effect of the hub wheel can be improved by providing the stainless steel slinger that does not easily rust on the outer periphery of the iron hub wheel that easily rusts.

The perspective view which shows the whole structure of the wheel bearing apparatus. Similarly sectional drawing. Sectional drawing which shows the structure of the seal mechanism of 1st embodiment. Sectional drawing which shows the structure of the seal mechanism of 2nd embodiment.

The wheel bearing device 1 will be described with reference to FIGS. 1 and 2.
FIG. 1 is a perspective view showing the overall configuration of the wheel bearing device 1. FIG. 2 shows an overall configuration of the wheel bearing device 1 by an AA sectional view in FIG. Below, it demonstrates according to the inner side and outer side which are shown by FIG.1 and FIG.2.

  The wheel bearing device 1 is a suspension device for a vehicle such as an automobile, and supports the wheel rotatably. The wheel bearing device 1 includes an outer member 2, an inner member 3, two inner ball rows 6a and outer ball rows 6b that are rolling rows, and an inner seal mechanism 7 that is a seal mechanism on the inner side. And an outer seal mechanism 10 as a seal mechanism which is a seal mechanism on the outer side. The inner member 3 includes a hub ring 4 and an inner ring 5.

  The outer member 2 is formed in a substantially cylindrical shape and is made of medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C. The outer member 2 includes an inner side opening 2a, an outer side opening 2b, an inner side outer rolling surface 2c, an outer side outer rolling surface 2d, a flange 2e, and an outer groove 2f. I have.

  The inner side opening 2a is formed at the inner side end of the outer member 2, and the inner seal mechanism 7 is fitted therein. The outer opening 2b is formed at the outer end of the outer member 2, and the outer seal mechanism 10 is fitted therein.

  The outer rolling surface 2c and the outer rolling surface 2d are formed in an annular shape along the circumferential direction on the inner circumferential surface of the outer member 2 so as to be parallel to each other. The outer rolling surface 2d is formed such that the pitch circle diameter is equal to or larger than that of the outer rolling surface 2c. A hardened layer having a surface hardness in the range of 58 to 64 HRC is formed on the outer rolling surface 2c and the outer rolling surface 2d by induction hardening.

  The vehicle body attachment flange 2e is integrally formed on the outer peripheral surface of the outer member 2 for attachment to a knuckle of a suspension device (not shown). The outer groove 2f is formed in an annular shape on the outer peripheral surface of the inner side opening 2a in order to drain rainwater from the outside.

  The inner member 3 supports a vehicle wheel (not shown) in a freely rotatable manner. The inner member 3 is inserted into the outer member 2. The inner member 3 includes a hub ring 4 and an inner ring 5.

  The hub wheel 4 is made of a medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C formed in a bottomed cylindrical shape. The hub wheel 4 includes a small-diameter step portion 4a, a flange 4b, an inner rolling surface 4c, and a hub bolt 4d.

  The small diameter step 4 a is formed at the inner side end of the hub wheel 4. The wheel mounting flange 4b is formed integrally with the hub wheel 4 at the outer side end of the hub wheel 4 in order to mount the wheel. The inner rolling surface 4 c is formed in an annular shape along the circumferential direction on the outer peripheral surface on the outer side of the hub wheel 4. The hub bolts 4d are provided at equidistant positions in the circumferential direction of the wheel mounting flange 4b.

  The inner ring 5 is press-fitted into the small-diameter step 4 a at the inner side end of the hub ring 4. The inner ring 5 is made of high carbon chrome bearing steel such as SUJ2, and is hardened in the range of 58 to 64 HRC up to the core part by quenching. The inner ring 5 is integrally fixed to the inner side end of the hub ring 4 in a state where a predetermined preload is applied by press-fitting.

  An annular inner rolling surface 5 a is formed on the outer peripheral surface of the inner ring 5 along the circumferential direction. The hub wheel 4 has a surface hardness of 58 to 64 HRC by induction hardening from the inner side small diameter step 4a to the outer side inner raceway 4c. Thereby, the hub wheel 4 has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 4b, and the durability of the hub wheel 4 is improved.

  In the hub wheel 4 and the inner ring 5, the inner rolling surface 5 a formed on the inner ring 5 at the inner end is opposed to the outer rolling surface 2 c on the inner side of the outer member 2 and is formed on the outer side. The inner rolling surface 4 c is disposed so as to face the outer rolling surface 2 d on the outer side of the outer member 2.

  The inner ball row 6a and the outer ball row 6b support the hub wheel 4 rotatably. In the inner ball row 6a and the outer ball row 6b, a plurality of balls as rolling elements are held in an annular shape by a cage. The inner ball row 6a and the outer ball row 6b are made of high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core portion by quenching.

  The outer ball row 6b is configured such that the pitch circle diameter is equal to or larger than that of the inner ball row 6a. The inner ball row 6a rolls between an inner rolling surface 5a formed on the inner ring 5 and an outer rolling surface 2c on the inner side of the outer member 2 facing the inner rolling surface 5a. It is sandwiched freely.

  The outer ball row 6b rolls between an inner rolling surface 4c formed on the hub wheel 4 and an outer rolling surface 2d on the outer side of the outer member 2 facing the inner rolling surface 4c. It is sandwiched freely. That is, the inner ball row 6 a and the outer ball row 6 b support the hub wheel 4 and the inner ring 5 so as to be rotatable with respect to the outer member 2.

  In this embodiment, the wheel bearing device 1 is configured as a double-row angular ball bearing including an outer member 2, a hub wheel 4, an inner ring 5, an inner ball row 6a, and an outer ball row 6b. However, the present invention is not limited to this. For example, this invention may be comprised with the double row tapered roller bearing.

  In the present embodiment, the wheel bearing device 1 is configured as a third-generation wheel bearing device 1 in which the inner raceway surface 4c of the outer ball row 6b is formed on the outer periphery of the hub wheel 4, The present invention is not limited to this. For example, the present invention includes a second generation structure in which a pair of inner rings 5 are press-fitted and fixed to the hub ring 4, or an outer ring that is an outer member 2 without the hub ring 4 and an inner ring 5 that is an inner member. It may be a first generation structure.

  The inner seal mechanism 7 seals the inner side of the annular space between the outer member 2 and the inner member 3. More specifically, the inner seal mechanism 7 closes the gap between the inner side opening 2 a of the outer member 2 and the hub wheel 4.

  The outer seal mechanism 10 seals the outer side of the annular space between the outer member 2 and the inner member 3. More specifically, the outer seal mechanism 10 closes the gap between the outer opening 2 b of the outer member 2 and the hub wheel 4. The outer seal mechanism 10 will be described later in detail.

  In the wheel bearing device 1, the gap between the inner side opening 2 a of the outer member 2 and the inner ring 5 is closed by the inner seal mechanism 7, and the gap between the outer side opening 2 b of the outer member 2 and the hub ring 4. Is closed by the outer seal mechanism 10. With this configuration, in the wheel bearing device 1, the hub wheel supported by the outer member 2 while preventing leakage of lubricating grease from the inside and intrusion of rainwater and dust from the outside. 4 and the inner ring 5 rotate.

The configuration of the outer seal mechanism 10 of the first embodiment will be described with reference to FIG.
In FIG. 3, the structure of the outer seal mechanism 10 is represented by an enlarged view of a portion B in FIG. In the following, description will be made according to the radial inner and outer sides, the inner and outer sides in the axial direction, the inner and outer sides of the annular space, and the circumferential direction shown in FIG.

  The outer seal mechanism 10 is a first embodiment of the seal mechanism of the present invention. The outer seal mechanism 10 seals the outer side of the annular space between the outer member 2 and the inner member 3. The outer seal mechanism 10 includes a first seal portion 11, a second seal portion 14, and a slinger 17.

  The outer side of the annular space between the outer member 2 and the inner member 3 is formed in a substantially L shape in a sectional view in the circumferential direction. More specifically, the outer side of the annular space is between the inner peripheral portion and the outer end surface of the outer member 2 and the outer peripheral portion 4l, R portion 4m, and base portion 4n of the hub wheel 4 of the inner member 3. Is formed.

  The first seal portion 11 is disposed at a midway portion that extends outward from the outer ball row 6 b in the annular space between the outer member 2 and the inner member 3. The first seal portion 11 is fitted on the inner peripheral side of the outer member 2. The first seal part 11 includes a core metal 12 and a first seal member 13.

  The core metal 12 is formed by pressing an austenitic stainless steel plate, a rust-proof cold-rolled steel plate, or a corrosion-resistant steel plate. The cored bar 12 includes a fitting part 12a and an inner part 12b. The fitting portion 12 a is formed in a cylindrical shape, and is fitted into the inner periphery of the outer side end portion of the outer member 2. The inner portion 12b is formed by bending from the fitting portion 12a and extends radially inward.

  The first seal member 13 is made of synthetic rubber such as NBR. The first seal member 13 is integrally vulcanized and bonded to a range from a part of the fitting portion 12a of the cored bar 12 to the radially inner end of the inner portion 12b. The first seal member 13 includes a radial lip portion 13a, a dust lip portion 13b, and a first side lip portion 13c.

  The radial lip portion 13 a extends toward the inner side of the annular space and the inner side in the radial direction, and is in sliding contact with the slinger 17. The dust lip 13 b extends toward the outer space side and the radially inner side of the annular space, and is in sliding contact with the slinger 17. The first side lip portion 13 c extends toward the outer space side of the annular space and toward the outer side in the radial direction, and is disposed with a predetermined gap with respect to the slinger 17.

  The second seal portion 14 is disposed in the vicinity of the end portion on the outer space side in the annular space between the outer member 2 and the inner member 3. The second seal portion 14 is fitted to the outer peripheral portion of the outer member 2. The second seal portion 14 includes a core metal 15 and a second seal member 16.

  The cored bar 15 is attached to the outer periphery of the outer side end portion of the outer member 2. The core 15 is formed by pressing an austenitic stainless steel plate, a rust-proof cold-rolled steel plate, or a corrosion-resistant steel plate. The core metal 15 includes a circumferential portion 15a, a standing plate portion 15b, and a flange portion 15c.

  The circumferential portion 15 a is formed in a cylindrical shape and is press-fitted into the outer peripheral surface of the outer member 2. The upright plate portion 15b extends from the circumferential portion 15a toward the radially outer side. The flange portion 15 c extends radially inward from the circumferential portion 15 a and is in close contact with the outer end surface of the outer member 2.

  The second seal member 16 is made of synthetic rubber such as NBR. The second seal member 16 is fixed in a range from the circumferential portion 15a of the core metal 15 to the inner side end portion of the standing plate portion 15b and the outer surface of the flange portion 15c. The second seal member 16 includes a second side lip portion 16a.

  The second side lip portion 16 a protrudes toward the hub wheel 4. The second side lip portion 16a is opposed to the outer member 2 along the inclined portion 4o with a predetermined clearance, and constitutes the first labyrinth R1.

  The slinger 17 is disposed along the outer peripheral portion 41, the R portion 4m, and the base portion 4n of the inner member on the outer side of the annular space between the outer member 2 and the inner member 3. The slinger 17 includes a metal core 18 and a slinger seal member 19.

  The core 18 is formed by pressing an austenitic stainless steel plate, a rust-proof cold-rolled steel plate, or a corrosion-resistant steel plate. The cored bar 18 includes an R portion 18a and a straight portion 18b.

  The R portion 18a is disposed along the outer peripheral portion 41, the R portion 4m, and the base portion 4n of the inner member. The straight portion 18b is disposed with a predetermined gap between the straight portion 18b and the base portion 4n.

  The slinger seal member 19 is made of synthetic rubber such as NBR. The slinger seal member 19 is fixed in a range from the outer side of the straight portion 18b of the cored bar 18 to the inner side of the R portion 18a. The slinger seal member 19 includes a first flange portion 19a and a second flange portion 19b.

  The straight portion 18b of the metal core 18 to which the slinger seal member 19 is fixed and the second side lip portion 16a are opposed to each other with a predetermined clearance to constitute a second labyrinth R2. In addition, 2nd labyrinth R2 may be comprised by the straight part 18b and the outer member outer side end surface.

  The first collar portion 19a is formed in a V shape in a sectional view. The first flange portion 19 a is disposed on the outer space side in the annular space of the slinger 17, and is disposed in the gap between the straight portion 18 b of the core metal 18 and the base portion 4 n of the hub wheel 4. Specifically, the first flange portion 19a is disposed in contact with the base portion 4n. The first flange portion 19a is arranged so as to open toward the external space side.

  The 2nd collar part 19b is formed in V shape by sectional view. The second flange portion 19 b is disposed on the outer space side and the inner side of the slinger 17. The second flange portion 19b is disposed on the outer space side in the annular space with respect to the first seal portion 11 in the annular space. The 2nd collar part 19b is arrange | positioned so that it may open toward the external space side.

The operation of the outer seal mechanism 10 will be described.
According to the outer seal mechanism 10, the muddy water is about to enter the outer side of the slinger 17 from the first labyrinth R1 between the second side lip portion 16a of the second seal portion 14 and the inclined portion 4o of the hub wheel 4. However, the muddy water to be infiltrated is secured by the first heel portion 19a, and the secured muddy water is discharged to the outside by the rotating first heel portion 19a. Therefore, muddy water does not enter between the slinger 17 and the outer peripheral portion 41, the R portion 4m, and the base portion 4n of the hub wheel 4.

  At the same time, according to the outer seal mechanism 10, when muddy water enters the inner side of the slinger 17 from the first labyrinth R 1 between the second side lip portion 16 a of the second seal portion 14 and the inclined portion 4 o of the hub wheel 4. Even so, the muddy water to be infiltrated is secured by the second heel portion 19b, and the secured muddy water is discharged to the outside by the rotating second heel portion 19b. Therefore, muddy water does not directly hit the first side lip portion 13c, and a decrease in the sealing force of the first side lip portion 13c can be suppressed.

  According to the outer seal mechanism 10, even if the muddy water exceeds the first labyrinth R1 of the second seal portion 14, the first collar portion 19a provided on the slinger 17 receives the muddy water, and the first collar portion 19a The muddy water received can be discharged to the outside during the rotation of the bearing.

  Further, according to the outer seal mechanism 10, the muddy water performance can be improved by the second labyrinth R2.

  Furthermore, according to the outer seal mechanism 10, even if the muddy water enters beyond the second labyrinth R2, the second heel portion 19b provided in the slinger 17 receives the muddy water, and the muddy water received by the second heel portion 19b. Can be discharged to the outside during rotation of the bearing. At the same time, muddy water does not directly contact the tip of the first side lip portion 13c of the first seal portion 11, and deterioration of the tip of the first side lip portion 13c can be prevented.

  Furthermore, according to the outer seal mechanism 10, the size of the dirt in the muddy water that prevents the large dirt in the infiltrated muddy water by the first labyrinth R 1 and prevents the small dirt in the infiltrated muddy water by the second labyrinth R 2. The muddy water performance can be improved by the labyrinth structure that is separated and prevented by the difference in height.

  Furthermore, according to the outer seal mechanism 10, the rust preventive effect of the hub wheel 4 can be improved by providing the stainless steel slinger 17 that is not easily rusted on the outer peripheral portion of the iron hub wheel 4 that is easily rusted.

The configuration of the outer seal mechanism 20 according to the second embodiment will be described with reference to FIG.
In FIG. 4, the structure of the outer seal mechanism 20 is represented by an enlarged view of a portion B in FIG. In the following, description will be made according to the inner side and outer side in the radial direction, the inner side and outer side in the axial direction, and the inner side and outer side of the annular space shown in FIG.

  The outer seal mechanism 20 is a second embodiment of the seal mechanism of the present invention. The outer seal mechanism 20 seals the outer side of the annular space between the outer member 2 and the inner member 3. The outer seal mechanism 20 includes a first seal portion 21, a second seal portion 24, and a slinger 27.

  The first seal portion 21 is disposed at a midway portion extending outward from the outer ball row 6 b in the annular space between the outer member 2 and the inner member 3. The first seal portion 21 includes a core metal 22 and a first seal member 23. Since the core metal 22 has the same configuration as the core metal 12, the description thereof is omitted.

  The first seal member 23 is made of synthetic rubber such as NBR. The first seal member 23 is integrally vulcanized and bonded in a range from a part of the fitting portion 22a of the cored bar 22 to the end portion on the radially inner side of the inner portion 22b. The first seal member 23 is formed to be inclined outward in the radial direction. The first seal member 23 includes a radial lip portion 23a, a dust lip portion 23b, a first side lip portion 23c as a lip seal, and a second flange portion 23d.

  The radial lip portion 23 a extends toward the inner side of the annular space and the inner side in the radial direction, and is in sliding contact with the slinger 27. The dust lip 23 b extends toward the outer space side and the radially inner side of the annular space, and is in sliding contact with the slinger 17. The first side lip portion 23 c extends toward the outer space side and the radially outer side of the annular space, and is in sliding contact with the slinger 27.

  The second flange 23d is provided on the outer space side of the annular space with respect to the first side lip 23c. The second flange 23d is formed in a V shape when viewed in cross section. The second flange portion 23 d is disposed on the outer side of the first seal portion 21. The second flange 23d is disposed on the outer space side of the first side lip 23c in the annular space. The second flange 23d is disposed so as to open toward the external space side.

  Since the second seal portion 24 has the same configuration as the second seal portion 14, the description thereof is omitted.

  The slinger 27 is disposed on the outer side of the annular space between the outer member 2 and the inner member 3 along the outer peripheral portion 41, the R portion 4m, and the base portion 4n of the inner member. The slinger 27 includes a metal core 28 and a slinger seal member 29. Since the core metal 28 has the same configuration as the core metal 18, the description thereof is omitted.

  The slinger seal member 29 is made of a synthetic rubber such as NBR. The slinger seal member 29 is fixed in a range from the outer side to the inner side of the straight portion 28b of the cored bar 28. The slinger seal member 29 includes a first flange portion 29a.

  The first collar portion 29a is formed in a V shape in a sectional view. The first flange portion 29 a is disposed on the outer space side and the outer side of the slinger 27. Specifically, the first flange portion 29a is disposed between the straight portion 28b and the base portion 4n. The first flange portion 29a is arranged so as to open toward the external space side.

  The first labyrinth R1 and the second labyrinth R2 of the outer seal mechanism 20 are the same as the first labyrinth R1 and the second labyrinth R2 of the outer seal mechanism 10, and thus the description thereof is omitted.

The operation of the outer seal mechanism 20 will be described.
According to the outer seal mechanism 20, the muddy water is about to enter the outer side of the slinger 27 from the first labyrinth R1 between the second side lip portion 26a of the second seal portion 24 and the inclined portion 4o of the hub wheel 4. However, the muddy water to be infiltrated is secured by the first flange 29a, and the secured muddy water is discharged to the outside by the rotating first flange 29a. Therefore, muddy water does not enter between the slinger 27 and the outer peripheral portion 41, the R portion 4m, and the base portion 4n of the hub wheel 4.

  At the same time, according to the outer seal mechanism 20, when muddy water enters the inner side of the slinger 27 from the first labyrinth R 1 between the second side lip portion 26 a of the second seal portion 24 and the inclined portion 4 o of the hub wheel 4. Even so, the infiltrated muddy water is secured by the second ridge portion 23d, and the secured muddy water is discharged to the outside through the second ridge portion 23d and below the second ridge portion 23d. Therefore, muddy water does not directly hit the first side lip portion 23c, and it is possible to suppress a decrease in the sealing force of the first side lip portion 23c.

  According to the outer seal mechanism 20, even if the muddy water exceeds the first labyrinth R1 of the second seal portion 24, the first flange portion 29a provided on the slinger 27 receives the muddy water, and the first flange portion 29a receives the muddy water. The muddy water received can be discharged to the outside during the rotation of the bearing.

  Further, according to the outer seal mechanism 20, the muddy water performance can be improved by the second labyrinth R2.

  Furthermore, according to the outer seal mechanism 20, even if the muddy water enters beyond the second labyrinth R2, the second flange 23d provided in the first seal portion 21 receives the muddy water and is received by the second flange 23d. The generated muddy water can be discharged to the outside during the rotation of the bearing. At the same time, the muddy water does not directly contact the tip of the first side lip portion 23c of the first seal portion 21, and deterioration of the tip of the first side lip portion 23c can be prevented.

  Furthermore, according to the outer seal mechanism 20, the size of the dirt in the muddy water that prevents the large dirt in the infiltrated muddy water by the first labyrinth R 1 and prevents the small dirt in the infiltrated muddy water by the second labyrinth R 2. The muddy water performance can be improved by the labyrinth structure that is separated and prevented by the difference in height.

  Furthermore, according to the outer seal mechanism 20, the rust prevention effect of the hub wheel 4 can be improved by providing the stainless steel slinger 27 which is not easily rusted on the outer periphery of the iron hub wheel 4 which is easily rusted.

DESCRIPTION OF SYMBOLS 1 Wheel bearing device 2 Outer member 2a Inner side opening 3 Inner member 4 Hub wheel 6a Inner ball row 6b Outer ball row 7 Inner seal mechanism 10 Outer seal mechanism 11 First seal portion 13c First side lip portion 14 First Two seal parts 17 Slinger 19a First collar part 19b Second collar part

Claims (3)

A wheel bearing device for rotatably supporting a wheel,
An outer member having an outer rolling surface formed on the inner peripheral side;
An inner member that is formed on the outer peripheral side and is inserted into the outer member while an inner rolling surface is formed,
A rolling element movably interposed between the outer rolling surface and the inner rolling surface;
Each sealing mechanism that seals the annular space formed between the outer member and the inner member on both sides of the wheel bearing device;
With
The inner member includes a hub ring and an inner ring,
The outer seal mechanism of the seal mechanisms includes a first seal portion, a second seal portion, and a slinger.
The slinger is disposed along the outer periphery of the inner member,
The first seal portion is fitted to the inner peripheral portion of the outer member, and is formed in order from the inside to the outside of the annular space, a radial lip portion, a dust lip portion, and a first side lip portion And comprising
The second seal portion includes a second side lip portion that is fitted to an outer peripheral portion of the outer member and protrudes toward the hub wheel, and the second side lip portion is a predetermined portion with respect to the hub wheel. The first labyrinth is constituted by the second side lip portion and the hub wheel, which is arranged to form a gap,
The slinger is on the outer space side of the annular space, and constitutes a second labyrinth with the slinger and the second side lip portion or the outer side end surface of the outer member.
Wheel bearing device. The wheel bearing device according to claim 1,
The slinger has a first flange formed in a gap between the slinger and the inner member and opening toward the outer space side of the annular space, and the annular space more than the first seal portion. On the outer space side, a second collar portion that opens toward the outer space side of the annular space is provided,
The radial lip portion extends toward the inner side of the annular space and the inner side in the radial direction, and is in sliding contact with the slinger.
The dust lip is extended toward the outer space side of the annular space and toward the inner side in the radial direction, and is in sliding contact with the slinger.
The first side lip portion extends toward the outer space side of the annular space and toward the outer side in the radial direction, and is disposed so as to form a predetermined gap with respect to the slinger.
Wheel bearing device. The wheel bearing device according to claim 1,
The first seal portion is provided with a second flange portion that opens toward the outer space side of the annular space on the outer space side of the annular space than the first side lip portion,
The radial lip portion extends toward the inner side of the annular space and the inner side in the radial direction, and is in sliding contact with the slinger.
The dust lip is extended toward the outer space side of the annular space and toward the inner side in the radial direction, and is in sliding contact with the slinger.
The first side lip portion extends toward the outer space side of the annular space and toward the outer side in the radial direction, and is in sliding contact with the slinger.
Wheel bearing device.