Bearing device for wheel and manufacturing method therefor
AssigneeNtn Corporation
InventorsHiroshi Matsunaga, Masahiro Tosaji
Life of this patent
Estimating the term…
Abstract
A bearing device for a wheel includes an outer member having double-row outer raceway surfaces formed on an inner circumference thereof, an inner member including a hub wheel having a wheel mounting flange formed thereon and at least one inner race fitted to a small-diameter step portion formed on an outer circumference of the hub wheel, the inner member having double-row inner raceway surfaces formed thereon so as to be opposed to the double-row outer raceway surfaces, and a plurality of rolling elements in spaces between the double-row inner and outer raceway surfaces. The at least one inner race being fixed in an axial direction thereof by a staked portion, the staked portion having a face spline formed on an end surface thereof by plastic working.
Claims16
A bearing device for a wheel, comprising:
- an outer member having double-row outer raceway surfaces formed on an inner circumference thereof;
- an inner member comprising:
- a hub wheel having a wheel mounting flange formed thereon;
- and
- at least one inner race fitted to a small-diameter step portion formed on an outer circumference of the hub wheel,
- the inner member having double-row inner raceway surfaces formed thereon so as to be opposed to the double-row outer raceway surfaces;
- and
- a plurality of rolling elements assembled into spaces between the double-row outer raceway surfaces and the double-row inner raceway surfaces,
- the at least one inner race being fixed in an axial direction thereof by a staked portion formed by plastically deforming an end portion of the small-diameter step portion of the hub wheel radially outward,
- the staked portion having a face spline formed on an end surface thereof by plastic working,
- wherein the following relationship is satisfied:
- S/M≦α×β
- where M represents a mean diameter of an outer diameter and an inner diameter of the end portion of the small-diameter step portion of the hub wheel before the staked portion is formed, S represents an outer diameter of the face spline, α represents a value indicating ductile elongation of a material for the hub wheel in terms of proportion, and β represents a correction coefficient depending on a type of process.
A manufacturing method for a bearing device for a wheel, the bearing device comprising:
- an outer member having double-row outer raceway surfaces formed on an inner circumference thereof;
- an inner member comprising:
- a hub wheel having a wheel mounting flange formed thereon;
- and
- at least one inner race fitted to a small-diameter step portion formed on an outer circumference of the hub wheel,
- the inner member having double-row inner raceway surfaces formed thereon so as to be opposed to the double-row outer raceway surfaces;
- and
- a plurality of rolling elements assembled into spaces between the double-row outer raceway surfaces and the double-row inner raceway surfaces,
- the at least one inner race being fixed in an axial direction thereof by a staked portion formed by plastically deforming an end portion of the small-diameter step portion of the hub wheel radially outward,
- the staked portion having a face spline formed on an end surface thereof by plastic working,
- the manufacturing method comprising forming the staked portion and forming the face spline in one step while satisfying the following relationship:
- S/M≦α×β
- where M represents a mean diameter of an outer diameter and an inner diameter of the end portion of the small-diameter step portion before the forming of the staked portion, S represents an outer diameter of the face spline after the forming of the staked portion, α represents a value indicating ductile elongation of a material for the hub wheel in terms of proportion, and β represents a correction coefficient depending on a type of process.
Dependencies are inferred from the claim text.