Abstract: A technique for net shaping gear teeth of a high performance power transmission gear from a powder metal workpiece includes heating a powder metal workpiece in the form of a near net shaped gear blank having gear teeth surfaces above its critical temperature to obtain an austenitic structure throughout its surfaces, isothermally quenching the workpiece at a rate greater than the critical cooling rate of its surfaces to a uniform metastable austenitic temperature just above the martensitic transformation temperature, rolling the gear teeth surfaces of the workpiece to a desired outer peripheral profiled shape between opposed dies, each die having an outer peripheral profiled surface, while holding the workpiece at the uniform metastable austenitic temperature, the gear teeth surfaces undergoing densification, plastic deformation, and strengthening as a result of the rolling operation, and cooling the workpiece through the martensitic range to thereby harden the surfaces of the gear teeth.

Abstract: A technique for net shaping gear teeth of a high performance power transmission gear from a powder metal workpiece includes heating a powder metal workpiece in the form of a near net shaped gear blank having gear teeth surfaces above its critical temperature to obtain an austenitic structure throughout its surfaces, isothermally quenching the workpiece at a rate greater than the critical cooling rate of its surfaces to a uniform metastable austenitic temperature just above the martensitic transformation temperature, rolling the gear teeth surfaces of the workpiece to a desired outer peripheral profiled shape between opposed dies, each die having an outer peripheral profiled surface, while holding the workpiece at the uniform metastable austenitic temperature, the gear teeth surfaces undergoing densification, plastic deformation, and strengthening as a result of the rolling operation, and cooling the workpiece through the martensitic range to thereby harden the surfaces of the gear teeth.

Abstract: A full form net shape roll finished contacting machine element such as a gear or sprocket is produced from a near net shape workpiece of wrought or forged steel including teeth with an initial outer peripheral contoured surface, each having a tooth flank with a nominally involute surface and a root/fillet region with a trochoidal surface. A rolling die is rotatably supported on a first axis. With the workpiece rotatably supported on a parallel distant second axis, the rolling die is advanced in an in-feed direction to meshingly engage with the workpiece. The involute surface of each tooth of the rolling die engages the involute surface of a mating tooth of the workpiece and the tooth tip of the rolling die engaging the trochoidal root/fillet surface between adjacent mating teeth of the workpiece to effect material flow along the outer peripheral contoured surface. This process continues for all of the teeth of the workpiece.

Abstract: A full form net shape roll finished contacting machine element such as a gear or sprocket is produced from a near net shape workpiece of wrought or forged steel including teeth with an initial outer peripheral contoured surface, each having a tooth flank with a nominally involute surface and a root/fillet region with a trochoidal surface. A rolling die is rotatably supported on a first axis. With the workpiece rotatably supported on a parallel distant second axis, the rolling die is advanced in an in-feed direction to meshingly engage with the workpiece. The involute surface of each tooth of the rolling die engages the involute surface of a mating tooth of the workpiece and the tooth tip of the rolling die engaging the trochoidal root/fillet surface between adjacent mating teeth of the workpiece to effect material flow along the outer peripheral contoured surface. This process continues for all of the teeth of the workpiece.

Abstract: A method and apparatus disclosed for cost-effective net shape precision ausform finishing the engagement surfaces of ball and roller bearings, for enhancing the surface strength and durability of bearing inner and outer races. The method consists of induction heating to austenitize the contacting surface layers of rolling element bearing races, followed by martempering (or marquenching), and then net shape roll finishing of the induction heated contacting surface layers in the metastable austenitic condition to finished dimensional accuracy requirements, and finally cooling to martensite. The apparatus utilizes a fixed vertical through-feed axis for the workpiece bearing race with capability for rotation and linear up and down positioning motion, and two coordinated and controlled laterally-moving infeed axes for roll finishing tooling dies.

Abstract: An optimization method of dressing a predetermined profile on the periphery of a grinding wheel of the type used in form grinding. A dresser is guided along a path corresponding to the predetermined grinding wheel profile in successive, identical cycles of motion. The grinding wheel is fed into the path in increments between cycles. The dresser contacts the periphery of the grinding wheel during movement along its path, with the duration of contact increasing in each cycle until the predetermined profile is produced. The duration of contact during each cycle is monitored. When the difference between the duration of contact in a given cycle and the duration of contact in the previous cycle is zero or negligible, dressing is complete. Apparatus for practicing the method is also disclosed.

Abstract: A grinder for form grinding gear teeth in which a work gear is positioned rotationally by a computer controlled drive. A sensitive probe in known angular relation to a grinding wheel about the axis of the gear is positioned at random in any tooth space, and senses the angular positions of the gear when the gear is driven in opposite directions into probe actuating positions of adjacent tooth surfaces. The computer then controls the gear drive to rotate it reversely by one half of such angular movement from the last position.