Wheel bearing unit having a multi-area seal

Abstract

The invention relates to a wheel bearing unit (10) for a vehicle, having a wheel hub rotatable about a rotational axis and connectable for torque transmission via spur gearing to a joint cap (12), a bearing device for rotatably mounting the wheel hub on a support element, and a sealing device (26) with at least one first sealing element (28) fixed relative to the wheel hub, wherein the sealing device has a second sealing element (30) embodied separately from the first sealing element and fixed relative to the joint cap and the first sealing element has a first radial portion (66) and a first axial projection (68) adjoining the first radial portion, and the second sealing element has a second radial portion (72) and a second axial projection (74) adjoining the second radial portion, wherein the first axial projection bears in a sealing manner against the second radial portion and / or the second axial projection bears in a sealing manner against the first radial portion as a function of an axial offset between the first and second sealing elements.

Description

[0001] P241461

[0002] -1 -

[0003] Wheel bearing unit with a multi-range seal

[0004] Description introduction

[0005] The invention relates to a wheel bearing unit according to the preamble of claim 1.

[0006] German patent DE 102022 104 768 A1 describes a wheel bearing unit for a motor vehicle with a wheel hub driven via a ball joint. The wheel hub and the ball joint, which is connected to a drive shaft, are non-rotatably connected to each other by a face gear. The wheel hub is rotatably mounted via a rolling bearing assembly. A wheel bearing seal is arranged on the rolling bearing assembly and includes a rotary encoder element for sensorially detecting the rotational speed.

[0007] The object of the present invention is to improve the sealing of a wheel bearing unit and to design the wheel bearing unit in the most space-saving and cost-effective way possible. The sealing function of the wheel bearing unit should be less dependent on tolerances.

[0008] At least one of these tasks is solved by a wheel bearing unit with the features according to claim 1. This allows the wheel bearing unit to be sealed more reliably and independently of radial and axial tolerances, while still being designed to be space-saving and cost-effective.

[0009] The vehicle can be a motor vehicle.

[0010] The bell housing can be connected to a drive shaft. The drive shaft can be part of the vehicle's drivetrain. The vehicle can be moved by a torque transmitted via the drive shaft to the bell housing and then, via the face gears, to the wheel hub.

[0011] The wheel hub can be designed to attach at least one vehicle wheel. The wheel hub can have a radial flange with holes for attaching it to the vehicle wheel. A brake disc can be attached to the wheel hub.

[0012] The face teeth can be positively engaged with a mating tooth on the joint bell in a toothed engagement. The face teeth and the mating tooth can together form a toothed section. A P241461

[0013] -2-

[0014] The drive torque for driving the vehicle wheel can be transmitted between the ball joint and the wheel hub via the face gearing.

[0015] The sealing device can be arranged to seal the meshing area of ​​the face gear with the mating gear. The sealing device can be an interface seal between the wheel hub and the ball joint. The sealing device can be a static seal.

[0016] The first and second sealing elements can be arranged at a right angle to each other. The first and / or second sealing element can be made of an elastomer.

[0017] The first sealing element can be fixed to the wheel hub or to a component that is at least rotationally connected to it in a rotationally fixed and / or axially fixed manner.

[0018] The second sealing element can be mounted on the joint housing or a component at least rotatably connected to it, and / or fixed axially. The second sealing element can have a sealing lip on a side facing axially away from the second axial projection. The sealing lip of the second sealing element can abut the joint housing or a component rotatably connected to it in a sealing manner.

[0019] The face teeth can be formed on a rolling rivet collar of the wheel hub. The face teeth can be formed directly during the manufacturing of the rolling rivet collar.

[0020] In a preferred embodiment of the invention, it is advantageous if the first axial projection is radially offset relative to the second axial projection. The first axial projection can be arranged radially inside or radially outside of the second axial projection. The first radial section can be arranged to at least partially radially overlap the second radial section.

[0021] In a particular embodiment of the invention, it is advantageous if the first radial section extends radially outwards from the first axial projection. Alternatively, the first radial section can extend radially inwards from the first axial projection.

[0022] A preferred embodiment of the invention is advantageous in which the second radial section extends radially inwards from the second axial projection. Alternatively, the second radial section can extend radially outwards from the second axial projection. P241461

[0023] -3-

[0024] In a specific embodiment of the invention, it is advantageous if the second radial section with the second axial projection is tiltable and / or the first radial section with the first axial projection is axially fixed at least in an axial direction away from the second axial projection. The first radial section can bear axially against a contact surface and thus be axially fixed in the axial direction. The contact surface can be located on the inner bearing ring and / or the wheel hub. The first radial section with the first axial projection can also be tiltable on the first sealing element.

[0025] In a preferred embodiment of the invention, it is advantageous if the wheel bearing unit further comprises at least one rotary encoder device, which is rotationally fixed relative to the wheel hub, for detecting a rotary movement, in particular of the wheel hub, by means of a rotary sensor. The rotary encoder device can have a sensor structure mounted circumferentially. The rotary sensor can detect the rotary movement without contact using the sensor structure. The detected rotary movement can be provided to a control system of the vehicle, in particular an ABS system and / or a tire pressure monitoring system.

[0026] A preferred embodiment of the invention is advantageous in which the rotary encoder device comprises a first rotary encoder element as a seal carrier for the first sealing element and / or a second rotary encoder element as a seal carrier for the second sealing element. The first rotary encoder element can be oriented primarily in the radial direction. The second rotary encoder element can be oriented primarily in the axial direction.

[0027] The first and / or second encoder element can be made of metal. The first and / or second encoder element can be magnetized. The first and / or second encoder element can have a sensor structure for detecting the rotary motion.

[0028] In a preferred embodiment of the invention, the first and second axial projections are arranged axially and / or radially between the first and second encoder elements. The second encoder element can axially cover the gear teeth between the spur gear and the mating gear. The first and / or second axial projections can be axially offset from the spur gear. The first and / or second axial projections can be arranged to at least partially overlap radially with the bearing assembly.

[0029] A preferred embodiment of the invention is advantageous in which the bearing device is a rolling bearing with a bearing outer ring and a rolling element P241461 relative to these.

[0030] -4- is designed as a rotatable inner bearing ring. The rolling elements can be rolling bodies, for example, balls. The rolling elements can be arranged radially between the outer bearing ring and the inner bearing ring. The face teeth can be axially offset relative to the rolling elements.

[0031] In a preferred embodiment of the invention, it is advantageous if the inner bearing ring is formed integrally with the wheel hub. This allows the number of components in the wheel bearing unit to be reduced.

[0032] In a specific embodiment of the invention, it is advantageous if the face teeth are formed on a rolling rivet collar of the wheel hub. The rolling rivet collar can axially secure the inner bearing ring and / or the rolling elements. The face teeth can be formed during the manufacturing of the rolling rivet collar.

[0033] Further advantages and advantageous embodiments of the invention will become apparent from the description of the figures and the illustrations.

[0034] Character description

[0035] The invention is described in detail below with reference to the illustrations. These show, in detail:

[0036] Figure 1: A section of a wheel bearing unit in a special embodiment of the invention.

[0037] Figure 2: A cross-section of a wheel bearing unit in a further special embodiment of the invention.

[0038] Figure 3: Section A from Figure 2 in an enlarged view.

[0039] Figure 4: A cross-section of a sealing device of a wheel bearing unit with different axial offsets.

[0040] Figure 1 shows a section of a wheel bearing unit in a special embodiment of the invention. The wheel bearing unit 10 for a vehicle comprises a wheel hub 16, connectable to and driven by a joint housing 12 and rotatable about a pivot axis 14, with a face toothing 18 for torque-transmitting connection with a mating toothing 20 of the joint housing 12, a bearing device 22 for rotatably mounting the wheel hub 16 on a support element 24, and a P241461

[0041] -5-

[0042] Sealing device 26 with a first sealing element 28 fixed opposite the wheel hub 16 and a second sealing element 30 designed separately from this and fixed opposite the joint bell 12.

[0043] The wheel hub 16 is attached to the ball joint 12 by a central screw 32. The ball joint 12 has a mating tooth 20 that meshes with the face teeth 18. A drive torque is transmitted between the ball joint 12 and the wheel hub 16 via this tooth meshing.

[0044] The wheel hub 16 comprises several bores 36 on a radial flange 34 for attachment to a vehicle wheel. Axially adjacent to the radial flange 34 is the bearing assembly 22, designed as a rolling bearing 38, with an outer bearing ring 40 and an inner bearing ring 44 rotatable relative to it via rolling elements 42. The rolling elements 42 are rolling elements 46, in this case balls, arranged in two rows, which are radially positioned between the inner bearing ring 44 and the outer bearing ring 40 and rotatably support the wheel hub 16 on the support element 24. The inner bearing ring 44 is preferably formed integrally with the wheel hub 16, and the outer bearing ring 40 is preferably formed integrally with the support element 24.

[0045] The bearing assembly 22 is axially sealed on one side by a bearing sealing device 48 and axially on the other side by a further bearing sealing device 50. The bearing sealing device 48 and the further bearing sealing device 50 are each designed as rotary seals.

[0046] The sealing device 26, on the other hand, is a static seal which, as an interface seal, seals the toothing area 52 of the face toothing 18 with the mating toothing 20.

[0047] Figure 2 shows a cross-section of a wheel bearing unit in a further specific embodiment of the invention. The bearing assembly 22 is arranged on the wheel hub 16. It comprises the outer bearing ring 40 and the inner bearing ring 44, which is rotatable relative to the outer bearing ring 40 via the rolling elements 42. For one row of rolling elements 42, the inner bearing ring 44 is a separate inner bearing ring 44' relative to the wheel hub 16, while for the other row of rolling elements 42, it is formed integrally with the wheel hub 16. The outer bearing ring 40 is formed integrally with the support element 24. The separately formed inner bearing ring 44' is received on an axial section of the wheel hub 16 and axially secured to the wheel hub 16 by a rolling rivet collar 54. The rolling rivet collar 54 has a face toothing 18 for meshing with the mating toothing 20 on the bearing housing 12. P241461

[0048] -6-

[0049] The toothing area 52 between the face toothing 18 and the mating toothing 20 is axially covered by the second sealing element 30.

[0050] Figure 3 shows an enlarged view of section A from Figure 2. The wheel bearing unit 10 further comprises a rotary encoder device 56, which is fixed relative to the wheel hub, for detecting rotary motion by means of a rotary sensor. The rotary encoder device 56 comprises a first rotary encoder element 58, oriented primarily in the radial direction, which serves as a seal carrier for the first sealing element 28, and a second rotary encoder element 60, oriented primarily in the axial direction, which serves as a seal carrier for the second sealing element 30. The first rotary encoder element 58 has a centering section 62 for receiving it on the inner bearing ring 44'.

[0051] The additional bearing sealing device 50 is arranged radially between the outer bearing ring 40 and the inner bearing ring 44' and is mounted in a rotationally fixed manner relative to the outer bearing ring 40. The additional bearing sealing device 50 comprises a sealing lip 64 which radially abuts the centering section 62 in a sealing manner. The centering section 62 is rotatable relative to the sealing lip 64.

[0052] The first sealing element 28 is arranged on the first rotary encoder element 58 as a sealing carrier and comprises a first radial section 66 and a first axial projection 68 adjoining it. The first radial section 66 extends radially outwards from the first axial projection 68 and connects radially to an axially wider sealing section 70, which is connected to the first rotary encoder element 58.

[0053] The second sealing element 30 is mounted on the second encoder element 60 as a seal carrier and comprises a second radial section 72 and a second axial projection 74 adjoining it. The second radial section 72 extends radially outwards from a sealing section 76 of the second sealing element 30, via which it is connected to the second encoder element 60, and runs radially inwards from the second axial projection 74. The second axial projection 74 is radially offset relative to the first axial projection 68.

[0054] The first axial projection 68 rests against the second radial section 72 and / or the second axial projection 74 rests against the first radial section 66, depending on an axial offset between the first and second sealing elements 28, 30 and thus between the wheel hub 16 and the ball joint 12, forming a seal. This allows the sealing device 26 to act as an interface seal, sealing the toothed area 52 more independently of radial and axial tolerances between the wheel hub and the ball joint 12. P241461

[0055] -7-

[0056] The second radial section 72 with the second axial projection 74 is tiltable and the first radial section 66 with the first axial projection 68 is axially fixed at least in an axial direction 78 away from the second axial projection 74 by axial contact with a contact surface 80 of the inner bearing ring 44'.

[0057] Figure 4 shows a cross-section of a sealing device of a wheel bearing unit with different axial offsets. In Figure 4a), the first and second sealing elements 28, 30 are offset from each other by an axial offset 82. The second axial projection 74, which extends radially outwards from the second radial section 72, abuts the first radial section 66 in a sealing manner. The first axial projection 68 is axially spaced from the second radial section 72.

[0058] The second radial section 72 with the second axial projection 74 is tiltable and if the axial offset 82 decreases further as shown in Figure 4 b), then the second radial section 72 can assume a modified tilting position, whereby the second axial projection 74 remains in sealing contact with the first radial section 66 or, as shown in Figure 4 c), with an even smaller axial offset 82, be tilted even more, whereby the second axial projection 74 remains in sealing contact with the first radial section 66, but the first axial projection 68 also rests against the second radial section 72, thus creating a radially offset double seal between the first and second sealing elements 28, 30.

[0059] If the axial offset 82 is further reduced as shown in Figure 4 d), only the first axial projection 68 is in sealing contact with the second radial section 72, while the second axial projection 74 is tilted away from the first radial section 66.

[0060] This allows at least one sealing system to be implemented between the first and second sealing elements 28, 30, regardless of the exact axial offset 82.

[0061] P241461

[0062] -8-

[0063] Reference symbol list

[0064] 10 wheel bearing unit

[0065] 12 Joint bell

[0066] 14 axis of rotation

[0067] 16 wheel hub

[0068] 18 Front teeth

[0069] 20 counter-gearing

[0070] 22 Storage device

[0071] 24 support element

[0072] 26 Sealing device

[0073] 28 first sealing element

[0074] 30 second sealing element

[0075] 32 Central screw

[0076] 34 Radial flange

[0077] 36 bore

[0078] 38 rolling bearings

[0079] 40 Bearing outer ring

[0080] 42 Rolling element

[0081] 44 inner bearing ring

[0082] 44' inner bearing ring

[0083] 46 rolling elements

[0084] 48 Bearing sealing device

[0085] 50 additional bearing sealing devices

[0086] 52 Gear area

[0087] 54 Roll rivet head

[0088] 56 Rotary encoder device

[0089] 58 first rotary encoder element

[0090] 60 second rotary encoder element P241461

[0091] -9-

[0092] 62 Centering section

[0093] 64 Sealing lip

[0094] 66 first radial section

[0095] 68 first axial projection 70 sealing section

[0096] 72 second radial section

[0097] 74 second axial projection

[0098] 76 Sealing section

[0099] 78 axial direction 80 contact surface

[0100] 82 Axial offset

Claims

P241461 -10- Patentansprüche 1. Wheel bearing unit (10) for a vehicle, comprising a wheel hub (16) connectable to a joint housing (12) for torque transmission via a face gear (18) and rotatable about an axis of rotation (14), a bearing device (22) for rotatably mounting the wheel hub (16) on a support element (24), a sealing device (26) with at least one first sealing element (28) fixed relative to the wheel hub (16), characterized in that the sealing device (26) has a second sealing element (30) designed separately from the first sealing element (28) and fixed relative to the joint housing (12), and the first sealing element (28) has a first radial section (66) and a first axial projection (68) adjoining it, and the second sealing element (30) has a second radial section (72) and a second axial projection (74) adjoining it, wherein, depending on an axial offset (82) between the first and second sealing element (28,30) the first axial projection (68) abuts the second radial section (72) and / or the second axial projection (74) abuts the first radial section (66) in a sealing manner.

2. Wheel bearing unit (10) according to claim 1, characterized in that the first axial projection (68) is radially offset relative to the second axial projection (74).

3. Wheel bearing unit (10) according to claim 1 or 2, characterized in that the first radial section (66) extends radially outwards from the first axial projection (68).

4. Wheel bearing unit (10) according to one of the preceding claims, characterized in that the second radial section (72) extends radially inwards from the second axial projection (74).

5. Wheel bearing unit (10) according to one of the preceding claims, characterized in that the second radial section (72) is tiltable with the second axial projection (74) and the first radial section (66) is tiltable with the first P241461 -11 - The axial projection (68) is axially fixed at least in an axial direction (78) away from the second axial projection (74).

6. Wheel bearing unit (10) according to one of the preceding claims, characterized in that the wheel bearing unit (10) further comprises at least one rotary encoder device (56) which is rotationally fixed relative to the wheel hub (16) for detecting a rotary movement by means of a rotary sensor.

7. Wheel bearing unit (10) according to claim 6, characterized in that the rotary encoder device (56) has a first rotary encoder element (58) as a sealing carrier of the first sealing element (28) and a second rotary encoder element (60) as a sealing carrier of the second sealing element (30).

8. Wheel bearing unit (10) according to claim 7, characterized in that the first and second axial projections (68, 74) are arranged axially and / or radially between the first and second encoder elements (58, 60).

9. Wheel bearing unit (10) according to one of the preceding claims, characterized in that the bearing device (22) is designed as a rolling bearing (38) with a bearing outer ring (40) and a bearing inner ring (44) rotatable relative to these via rolling elements (42).

10. Wheel bearing unit (10) according to claim 9, characterized in that the inner bearing ring (44) is formed integrally with the wheel hub (16).

Images