Wheel Bearing Apparatus Incorporated With A Wheel Speed Detecting Apparatus

• US 20090285515A1
• Filed: 07/24/2009
• Published: 11/19/2009
• Est. Priority Date: 01/25/2007
• Status: Active Grant

• Current Assignee: NTN Corporation
• Original Assignee: NTN Corporation
• Inventors: Yamamoto, Kazunari, Kawamura, Hiroshi
• Granted Patent: US 8,043,010 B2
• Time in Patent Office: Days
• US Class Current: 384/448
• CPC Class Codes: F16C 19/186 with three raceways provided integrally on parts other than race rings, e.g. third generation hubs
• CPC Class Codes: F16C 2326/02 Wheel hubs or castors in general B60B
• CPC Class Codes: F16C 33/7879 with a further sealing ring
• CPC Class Codes: F16C 33/805 in addition to other sealings, e.g. dirt guards to protect sealings with sealing lips
• CPC Class Codes: F16C 41/007 Encoders, e.g. parts with a plurality of alternating magnetic poles
• CPC Class Codes: G01P 3/443 mounted in bearings bearings F16C
• CPC Class Codes: G01P 3/487 delivered by rotating magnets

Abstract

A wheel bearing apparatus incorporating a wheel speed detecting apparatus has an outer member and an inner member with a wheel hub and at least one inner ring. Double row rolling elements are contained between the inner and outer raceway surfaces of the inner and outer members. A sensor holder, with a wheel speed sensor to detect the wheel speed, is mounted on the end of the outer member. An encoder is mounted on the inner ring and arranged opposite to the wheel speed sensor, via a predetermined air gap. The sensor holder has an annular ring shaped cover and a holding portion of synthetic resin. The wheel speed sensor is embedded in the holding portion. The cover is press-formed of an anti-corrosion steel sheet. The cover has a cylindrical fitting portion fit onto the end of the outer member. A flange portion extends from the fitting portion and is in close contact with the end face of the outer member. A bottom portion further extends radially inward from the flange portion. At least the outer circumference of the end of the outer member onto, where the cover is fit, is anti-corrosion treated.

Claims

1. A wheel bearing apparatus incorporating a wheel speed detecting apparatus comprising:

an outer member integrally formed, on its outer circumference, with a body mounting flange to be mounted on a knuckle of a vehicle, said outer member inner circumference including double row outer raceway surfaces;

an inner member including a wheel hub and at least one inner ring, the wheel hub being integrally formed at one end with a wheel mounting flange, a cylindrical portion axially extending from the wheel mounting flange, the inner ring being press fit onto the cylindrical portion of the wheel hub, the wheel hub and the inner ring being formed on their outer circumferences with double row inner raceway surfaces opposite to the double row outer raceway surfaces;

double row rolling elements are contained between the inner and outer raceway surfaces of the inner and outer members;

a sensor holder adapted to be mounted on the end of the outer member, said sensor holder including a wheel speed sensor for detecting the wheel speed;

an encoder mounted on the inner ring and arranged opposite to the wheel speed sensor via a predetermined air gap;

the sensor holder further including an annular ring shaped cover and a holding portion of synthetic resin, the wheel speed sensor is embedded in said holding portion, the cover is press-formed of a anti-corrosion steel sheet and further comprises a cylindrical fitting portion adapted to be fit onto the end of the outer member, a flange portion extending from the fitting portion and adapted to be in close contact with the end face of the outer member, and a bottom portion further extending radially inward from the flange portion, and at least the outer circumference of the end of the outer member, onto which the cover is fit, is anti-corrosion treated.

2. The wheel bearing apparatus incorporating a wheel speed detecting apparatus of claim 1, wherein said cover is formed of a non-magnetic austenitic stainless steel sheet.

3. The wheel bearing apparatus incorporating a wheel speed detecting apparatus of claim 1, wherein said outer member is formed of martensitic stainless steel.

4. The wheel bearing apparatus incorporating a wheel speed detecting apparatus of claim 1, wherein the inner diameter of the bottom portion of the cover is smaller than the outer diameter of the inner ring, and a labyrinth seal having a predetermined gap between the end of the bottom portion and the end face of the inner ring as well as the outer circumference of the outer joint member forming part of a constant velocity universal joint.

5. The wheel bearing apparatus incorporating a wheel speed detecting apparatus of claim 1, wherein a drain is formed on the bottom portion of the cover.