Patent ID: 8574028

Claim:
An improved grinder polisher, comprising: a base having a bowl, a rotating drive plate and a drive plate drive, the drive plate adapted to support a platen; a head configured to support a specimen holder and having a first drive for rotational drive of the specimen holder, the head having a second drive for moving the head and the specimen holder toward and away from the platen, the head including a load cell operably connected to the first drive and a counter configured to determine movement and the extent of movement of the head toward and away from the platen; a lead screw for moving the specimen holder toward and away from the platen, the lead screw being connected to the counter, wherein a lead screw gear is mounted to the lead screw, and the counter is driven by a pinion gear that is meshed with the lead screw gear, wherein the lead screw gear is larger than the pinion gear; and a control system.