Patent ID: 6151778
Filing Date: 2000-11-28
Classification: B21H,B22F,B23P,Y10T

Abstract:
A method of modifying a gear cutting machine tool normally equipped with a gear cutting die to facilitate roll form densification of the teeth of powder metal fear preforms; comprising:supporting a sintered powder metal gear preform having preformed teeth on a workpiece spindle of the machine tool for rotation about a first axis;replacing the gear cutting die of the machine tool with a roll forming die supported on a tool spindle for rotation about a second axis transverse to the first axis and having a roll forming surface substantially free of cutting features that would act to remove material from the preform during a roll forming operation;bringing the roll forming surface into meshing engagement with the teeth of the preform;fixing the transverse angular orientation of the first axis relative to the second axis;positively driving the tool spindle and roll forming die about the second axis to impart synchronous driven rotation of the preform about the first axis; andwhile driving the roll forming die about the second axis, positively driving the preform about the first axis out of sync with the drive of the roll forming die thereby to impart binding interference between the roll forming die and the preform sufficient to cause displacement and material densification of the teeth of the powder metal preform.