Patent ID: 7270598

Claim:
An orbital palm sander comprising: an elongate tubular housing aligned along the central axis having a first end, a second end and a central tubular region in the second end and sized to allow an operator to grasp and operate the sander with a single hand about the central axis; a high speed permanent magnet DC motor disposed within the housing central tubular region, the motor having a cylindrical body with a central axis and a rotary motor shaft generally coaxially aligned with the central axis; an eccentric drive shaft rotatably driven by the motor shaft about the central axis and having a drive member eccentrically offset from the central axis; a sanding platen oriented adjacent to the housing second end and orbitally driven by the drive member, the platen having a planar surface perpendicular to the central axis adapted to receive sand paper; a bearing interposed between the sanding platen and the eccentric drive shaft drive member freely rotatably connecting the sanding platen and drive member to cause the sanding platen to orbit as the motor rotates; and a fan including a disc extending about and lying in a plane perpendicular to the motor axis and including a plurality of generally uniformly shaped blades circumaxially spaced about the disc in a non-uniform manner to balance the eccentric drive and sanding platen about the motor axis.