Patent ID: 7712401

Claim:
A cutting head assembly for attachment to an on-vehicle brake disk lathe that mounts to a wheel hub of a vehicle on which a brake disk is mounted, the on-vehicle brake disk lathe having a base, a platform and means for moving the platform in a direction normal to the axis of rotation of the brake disk, the cutting head assembly comprising: a platform key attached to the platform and extending parallel to the disk axis when the brake lathe is mounted and aligned with respect to the brake disk; a plate having a plate keyway configured to slidably engage said platform key, said plate engaging the platform so as to remain slidably engaged therewith when the cutting head assembly is inverted; a pair of tool bit arms adjustably mounted with respect to said plate and each serving to support and position a tool bit mounted thereto; means for adjusting the separation between the tool bits mounted to said tool bit arms; means for locking said tool bit arms in position with respect to said plate; a cam for locking said platform key with respect to said plate keyway, said cam residing principally in said plate and being located in a region of said plate bounded by the projection of said tool bit arms onto said plate, said cam also providing means for applying a force to said region of said plate bounded by the projections of said tool bit arms to generate a compressive load between said plate and the platform responsive to activating said cam.