Patent ID: 6761513
Filing Date: 2004-07-13
Classification: B23Q,Y10T

Abstract:
A drill, comprising:a frame having a longitudinal axis; a motor assembly having a chuck adapted to receive a drill bit for rotation therewith, the motor being carried by the frame for movement relative to the frame; a pneumatic cylinder assembly mounted between the motor assembly and the frame for moving the motor assembly axially relative to the frame, the pneumatic cylinder assembly being balanced about the axis such that any moments generated by the pneumatic cylinder assembly on one side of the axis are offset by moments on an opposite side of the axis; and a hydraulic fluid restrictor assembly mounted between the motor assembly and the frame for restricting a rate of axial movement of the motor assembly relative to the frame, the fluid restrictor assembly being balanced about the axis such that any moments generated by the fluid restrictor assembly on one side of the axis are offset by moments on an opposite side of the axis.