Patent ID: 9180639
Filing Date: 2015-11-10
Classification: B21J,B21K,B29D,B60B,F16C,F16D

Abstract:
1. A method of forming, by plastic deformation, a frontal toothing on an inner ring of a wheel hub, comprising: forming the inner ring of the wheel hub by joining of a spindle and an insert ring, the insert ring being fitted onto a side of the spindle; axially blocking the insert ring on the spindle by plastically deforming a first end of the spindle so as to form an upset collar therewith which axially protrudes from the insert ring such that the insert ring is located on a first axial side of the upset collar; and impressing the frontal toothing onto the upset collar on a second axial side, opposite to the first axial side thereof such that the frontal toothing is located on a side of the upset collar opposite to the insert ring; and wherein the operation of impressing the frontal toothing directly onto the upset collar is carried out sequentially after ending the operation of forming the upset collar, the operation of impressing the frontal toothing is carried out by a single, cylindrical-symmetry creator tool provided with a toothing which faces toward the upset collar and is complementary to that to be obtained, by axially impressing onto the upset collar, in sequence, one or more teeth of the complementary toothing by eccentrically pushing the creator tool against the upset collar while the creator tool is held substantially coaxial to the wheel hub, acting peripherally in sequence on the whole creator tool, wherein the creator tool is eccentrically pushed against the upset collar by using a pressing head frontally delimited by a conical surface, rotating the pressing head about a first axis (B) arranged inclined with respect to an axis of symmetry (A) of the wheel hub while simultaneously rotating the first axis (B), with precession motion, about the symmetry axis (A) of the wheel hub, the creator tool is eccentrically pushed against the upset collar in an indirect manner by a passive element interposed between the creator tool and an active element consisting of the pressing head and exerting an eccentric thrust on the passive element, wherein an elastically deformable, circular flat metal plate is used as the passive element which is frontally held against the creator tool, from a side opposite to the complementary toothing, the elastically deformable, circular flat metal plate having a peripherally outer, thinned edge thereof which protrudes past a corresponding radially outer edge of the creator tool and which is restrained by a restrain joint to a supporting structure of the creator tool.