Rolling bearing unit for a drive wheel and a wheel driving unit
First Claim
1. A rolling bearing unit for a drive wheel comprising an outer ring, a hub, an inner ring, and a plurality of rolling elements, wherein:
- said outer ring has, on the outer peripheral surface thereof, a first flange to be coupled and fixed to a suspension device, and on the inner peripheral surface thereof, a plurality of outer ring raceways;
said hub has a spline hole in the center thereof, a second flange for supporting and fixing a drive wheel in a part closer to the outer end of an outer peripheral surface of the hub, and a first inner ring raceway formed on an inner ring element integrally or separately formed with the hub in an intermediate portion of the outer peripheral surface;
said inner ring has a second inner ring raceway on the outer peripheral surface thereof;
said rolling elements are provided rotatably between said outer ring raceways and said first and second inner ring raceways, respectively;
the inner peripheral surface and the axially inner end surface of said inner ring are formed to be continuous by a chamfered portion having a convex arc-shaped cross section;
said hub has a cylindrical section formed on the axially inner end portion of said hub in a part inner in the axial direction than the spline hole, and the inner end portion in the axial direction of this spline hole and the inner peripheral surface of the outer end portion in the axial direction of said cylindrical section are continuous by an inclined surface portion in a conical concave form which is inclined in a direction in which the diameter thereof becomes larger at an inner position in the axial direction;
the following condition is satisfied;
L≧
30·
(B/A)−
16, where a distance between a border position between said inclined surface portion and the inner peripheral surface of said cylindrical section and the axially outer end portion of said chamfered portion is L mm (a positive value when the border position is, in the axial direction, outside of said axially outer end portion), the thinnest part of the spline portion of the hub (the outer diameter of the cylindrical section—
the diameter of a groove bottom circle of the spline)/2) is A mm, and the thickness of the hub at the border position between said inclined surface portion and the axially inner peripheral surface of said cylindrical section is B mm;
said inner ring is fitted to said hub with the axially inner end surface being pressed by a crimping portion of the hub in the axially inner end portion of said hub; and
said inner ring is fixed on said cylindrical section by crimping said cylindrical section.
1 Assignment
0 Petitions
Accused Products
Abstract
A rolling bearing unit for a drive wheel comprises a hub and a double row rolling bearing thereon. The hub has a first inner ring raceway formed on an inner ring element integrally or separately formed with the hub in an intermediate portion, and a fit cylindrical surface section in a part closer to the inner end of the outer peripheral surface. A separate inner ring having a second inner ring raceway is fitted on the hub, with the axially inner end surface pressed by a caulking portion formed by plastically deforming a cylindrical section formed in the axially inner end portion of the hub in a state that the inner ring is fitted on the fit cylindrical surface section, to be fixed to the hub.
20 Citations
2 Claims
-
1. A rolling bearing unit for a drive wheel comprising an outer ring, a hub, an inner ring, and a plurality of rolling elements, wherein:
-
said outer ring has, on the outer peripheral surface thereof, a first flange to be coupled and fixed to a suspension device, and on the inner peripheral surface thereof, a plurality of outer ring raceways;
said hub has a spline hole in the center thereof, a second flange for supporting and fixing a drive wheel in a part closer to the outer end of an outer peripheral surface of the hub, and a first inner ring raceway formed on an inner ring element integrally or separately formed with the hub in an intermediate portion of the outer peripheral surface;
said inner ring has a second inner ring raceway on the outer peripheral surface thereof;
said rolling elements are provided rotatably between said outer ring raceways and said first and second inner ring raceways, respectively;
the inner peripheral surface and the axially inner end surface of said inner ring are formed to be continuous by a chamfered portion having a convex arc-shaped cross section;
said hub has a cylindrical section formed on the axially inner end portion of said hub in a part inner in the axial direction than the spline hole, and the inner end portion in the axial direction of this spline hole and the inner peripheral surface of the outer end portion in the axial direction of said cylindrical section are continuous by an inclined surface portion in a conical concave form which is inclined in a direction in which the diameter thereof becomes larger at an inner position in the axial direction;
the following condition is satisfied;
L≧
30·
(B/A)−
16,where a distance between a border position between said inclined surface portion and the inner peripheral surface of said cylindrical section and the axially outer end portion of said chamfered portion is L mm (a positive value when the border position is, in the axial direction, outside of said axially outer end portion), the thinnest part of the spline portion of the hub (the outer diameter of the cylindrical section—
the diameter of a groove bottom circle of the spline)/2) is A mm, and the thickness of the hub at the border position between said inclined surface portion and the axially inner peripheral surface of said cylindrical section is B mm;
said inner ring is fitted to said hub with the axially inner end surface being pressed by a crimping portion of the hub in the axially inner end portion of said hub; and
said inner ring is fixed on said cylindrical section by crimping said cylindrical section. - View Dependent Claims (2)
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Specification