Abstract: A lightweight drive axle includes an elongate, tubular body having a first longitudinal end configured for coupling to a side gear in a differential and a second longitudinal end configured to support a vehicle wheel. The shaft further includes a screw disposed at the first longitudinal end of the body. The screw comprise a shank configured to be received within a bore in the body and a head having first and second portions. The first portion is disposed at one longitudinal end of the screw, has a first diameter and is spaced from the first longitudinal end of the body. The second portion is disposed between the first portion and the shank and has a second diameter less than the first diameter such that the first longitudinal end of the body and the first and second portions of the head define a groove configured to receive a shaft retainer.

Abstract: A method for forming a lightweight axle shaft is provided. A first tubular blank is inserted in a die defining an extrusion throat at one end. A tool is inserted into the die having a mandrel with portions of increasing diameter. The tool is moved towards the outlet end of the die to partially extrude the blank through the extrusion throat and form a hollow axle shaft having a variable inner diameter based on the varying diameter of the mandrel. The tool is then removed and a second tubular blank is inserted and placed in engagement with the first blank. The tool, or a different tool, is inserted into the die and again moved towards the outlet end of the die to complete extrusion of the first blank and produce a shaft having diameters at each end that are less than the diameter of an intermediate portion of the shaft.

Abstract: A method for manufacturing a one-piece axle tube housing with localized sections of increased wall thickness includes providing a tube blank, inserting a mandrel having a reduced diameter profile, passing the tube through an extrusion die to conform the tube to the shape of the mandrel; and extraction of the mandrel from the tube to cause outward deformation of the tube at specific locations. A further reducing step may be used to form the final desired profile, including reduced inner and outer diameters along sections of the axle tube housing.

Abstract: A method for manufacturing a one-piece axle tube housing with localized sections of increased wall thickness includes providing a tube blank, inserting a mandrel having a reduced diameter profile, passing the tube through an extrusion die to conform the tube to the shape of the mandrel; and extraction of the mandrel from the tube to cause outward deformation of the tube at specific locations. A further reducing step may be used to form the final desired profile, including reduced inner and outer diameters along sections of the axle tube housing.

Abstract: A method for forming a variable wall thickness axle or tube with internally thickened wall sections comprises extruding a tubular metal blank within an elongated die. An elongated punch pushes the blank through the die. The punch has an end abutting and pushing the blank into and through the die and an elongated portion which is spaced from the interior wall surface of the die. Movement of the punch in pushing the blank causes the blank to partially extrude forwardly through the die until stopped and then to extrude rearwardly around the punch elongated portion through the space for forming a tube. A tubular ring is then inserted within the extruded tube at a pre-determined location and is fixed in place to provide a thick, combined tube wall and ring wall, section which extends radially inwardly of the tube. A number of spaced-apart rings may be used to provide spaced-apart thickened wall sections within the tube.

Abstract: A vehicle dead axle is formed of a hollow tube that extends substantially the width of the vehicle and has wheel supporting spindle portions welded upon the opposite ends of the tube. The exterior surface of the tube is generally circular in cross-section. The cross-sectional shape of the opening in the tube is asymmetrically curved relative to the central axis of the tube to form the tube into integral, longitudinally extending, circumferential wall segments of varying wall thicknesses. The axle is oriented so that its thicker wall segments receive the greater of anticipated forces imposed upon the axle during use. The axle is formed by placing a tubular blank within an open die having a die throat and pushing the blank through the die throat by means of a moving ram that engages and pushes against the end of the blank. The ram has an extension that is fitted within the blank as the ram pushes the blank through the space between the extension and the die throat.

Abstract: A process for cold forming tubular axles comprises placing a tubular blank within an open ended die having a constricted die throat, and pushing the blank through the die throat with a punch. The punch is provided with a portion that presses the blank axially through the die throat. In addition, the punch has at least one extension which is closely fitted within the blank so that as the punch pushes a portion of the tube axially through the die throat, the extension is arranged within the die throat to form an annular space between the extension and the die throat. The punch extension is substantially elliptical in cross-section while the die throat is substantially circular in cross-section. Thus, the portion of the blank extruded through the space is formed with a substantially circular exterior wall and a substantially elliptical interior wall which provides diametrically opposing thicker wall sections and diametrically opposing thinner wall sections that are 90.degree.

Abstract: A torsional damper for reducing the vibrations produced when a shaft is driven by the intermittent application of a discontinuous force thereto, e.g. the crankshaft of an internal combustion engine, comprising an integrally formed disk-like mass having three concentric zones, namely, an inner central zone, an outer annular zone, and an intermediate spring zone therebetween. The spring zone includes narrow, elongated, spirally-arranged, overlapping slots extending axially through the disk and radially between the inner and outer zones to provide spirally-arranged overlapping web portions which act as torsional springs or shock absorbers due to an inherent resiliency. The spirally slotted damper is formed as an integral unit by casting it from a metal such as cast iron with the spiraled slots having a predetermined size and shape to provide the desired damping effect.