Abstract: A cylindrical wheel rim blank has a longitudinal seam defined by a pair of longitudinal edge portions each of which is clamped between upper and lower jaws of a respective clamping assembly. The two clamping assemblies are urged laterally together to press the two longitudinal edge portions together, and welding current is introduced at the seam through the lower jaws to effect the weld. The upper jaws are at the bottom of cantilevered horn members around which the rim blank is mounted. The lower jaws are urged upwardly toward the cantilevered upper jaws to effect the clamping function. Structure is provided to equalize the clamping pressure exerted against the upper jaw along the length thereof and, if desired, to introduce a bias into the upward pressure exerted through the lower jaw. There is a mechanism to provide different, predetermined spacings between the clamping assemblies as different steps in the operation. Circuitry is provided to produce a reversing, pulsating DC welding current.

Abstract: A tubular metal workpiece undergoes radial forging employing shrink forming. A multiplicity of dies are arranged circumferentially around the workpiece and urged radially inwardly in a first shrink forming pass to decrease the diameter of the workpiece. The dies are retracted, the workpiece is rotated slightly and another shrink forming pass is performed. The workpiece is then advanced axially, and the procedure described above is repeated. Procedures are employed to prevent torsional deformation and radially outward extrusion of metal in the gaps between adjacent dies.

Abstract: The longitudinal edge portions of a cylindrical wheel rim blank are gripped by a pair of laterally spaced clamping assemblies each having a radially fixed inside clamping member and each having a radially movable outside clamping member adapted to clamp the blank against the inside member. After the rim blank has been clamped, the two clamping members of one of the clamping assemblies are pivoted laterally toward the clamping members of the other assembly to press the edges of the rim blank against one another preparatory to welding current being directed through the blank to weld the edges. A load cell detects the force applied to the pivoted clamping assembly and produces a signal which is used to monitor or control the force.

Abstract: An electric drive system for automotive wheel rim forming equipment having inner and outer forming rolls mounted on driven spindles. The drive system includes separate drives for each forming roll and a control system for maintaining a predetermined speed ratio between the forming rolls in the absence of a working load thereon. The control system further maintains a predetermined torque ratio between the outputs of the drives for the forming rolls during the forming of a wheel rim by the forming rolls.

Abstract: A removable cartridge for insertion in a shrink forming machine having a multiplicity of circumferentially arranged radially movable machine jaws. The cartridge fits inside the machine jaws and is insertable and removable as a unit. The cartridge comprises a multiplicity of circumferentially arranged, radially movable cartridge jaws each engaged by a respective machine jaw to move the cartridge jaw inwardly. A die is mounted on the radially inward end of each cartridge jaw. Guidance structure protects against any substantial deviation by the die from a precise radial path of movement. Structure is provided to enable the cartridge jaw to absorb the load, developed during a shrink forming operation, within the limits of the relatively commonplace physical properties of the material of which the cartridge jaw is composed.

Abstract: An electric drive system for automotive wheel rim forming equipment having inner and outer forming rolls mounted on driven spindles. The drive system includes separate drives for each forming roll and a control system for maintaining a predetermined speed ratio between the forming rolls in the absence of a working load thereon. The control system further maintains a predetermined torque ratio between the outputs of the drives for the forming rolls during the forming of a wheel rim by the forming rolls.

Abstract: An electric drive system for automotive wheel rim forming equipment having inner and outer forming rolls mounted on driven spindles. The drive system includes separate drives for each forming roll and a control system for maintaining a predetermined speed ratio between the forming rolls in the absence of a working load thereon. The control system further maintains a predetermined torque ratio between the outputs of the drives for the forming rolls during the forming of a wheel rim by the forming rolls.

Abstract: A roll forging machine has a pair of opposed work rolls carrying cooperating dies and a pair of support rails mounted on each work roll on opposite sides of the die thereon. The support rails provide the work rolls with a high spring constant, so that the supporting framework can have a relatively low spring constant. During forging the work rolls are urged together with a force substantially greater than the force required to forge the workpiece, and the opposed support rails are pressed together to prestress the work rolls. The dies and support rails occupy only preselected segments of the circumferences of the work rolls, and a pair of backup rolls bear against each work roll on the balance of the circumference. The two backup rolls for each work roll are positioned asymmetrically with respect to the plane of the workpiece, with the backup roll on the feed side of the work roll being located farther away from the plane of the workpiece than is the other backup roll.

Abstract: Metal pipe is planished by passing it longitudinally between two concentric circular arrays of independently rotatable planishing elements which are urged against the inner and outer surfaces of the pipe. The two circular arrays of planishing elements are radially aligned with each other on opposite sides of the pipe wall, and the pipe is rotated relative to the two arrays of planishing elements while the pipe is being passed therebetween.

Abstract: A welding machine for welding the longitudinal seams in wheel rim blanks which have been rolled into cylinders with the longitudinal edges of each blank forming a longitudinal gap includes a pair of clamping assemblies each having an inside member and an outside member for engaging the inner and outer surfaces, respectively, of the rim blank adjacent the longitudinal edges thereof on opposite sides of the longitudinal gap so as to align the longitudinal edges with each other. At least one of the clamping assemblies is movable relative to the other clamping assembly in a direction transverse to the longitudinal gap so as to permit the longitudinal edges of the rim blank to be pressed against each other. The longitudinal edges of the blank are pressed together in the transverse direction to close the gap and hold the longitudinal edges together during the welding thereof.

Abstract: Method and apparatus for single plane, balance determination of cylindrical parts and the like, particularly adapted for use with determining imbalance of unmounted tires. The tire to be tested for balance is supported for rotation about a horizontal axis and driven in a substantially constant slow speed while torque monitoring means generates an output proportional to the variations in torque resulting from driving of the support means, electrical signal conversion means determines the magnitude of imbalance as being one half the difference between the maximum and minimum torque output values which is shown on a visual output display. A marking device is triggered to indicate the position on the tire at the instant the maximum torque output occurs to locate the position of the center of gravity on a horizontal line moving upward around the rotation axis.