Patent ID: 7536936

Claim:
An on-car brake lathe system for resurfacing a brake disk of a vehicle brake assembly coupled to a vehicle axle, the brake lathe system having a support structure, an adjustable cutting head secured to the support structure, and an output spindle secured to the support structure and rotationally driven about a drive axis, comprising: a motor secured to said support structure, and operatively coupled to said output spindle to rotationally drive said output spindle about the drive axis in one of two selectable rotational directions; a drive system operatively coupled to said motor for regulating a flow of electrical current to said motor, said drive system including a pulse width modulation motor controller; and wherein said pulse width modulation motor controller has a variable duty cycle which is selectively controlled between 100% and 0%, and wherein a duty cycle of 0% achieve a maximum torque in said spindle motor in said first rotational direction, a duty cycle of 50% prevents rotational movement of the spindle motor; and a duty cycle of 100% achieves a maximum torque in said spindle motor in said second rotational direction.