US Patent 6866570 Variable speed reciprocating linear sliding dual floor sander

A non-rotary, linear reciprocating floor sander includes a housing having a bottom opening, wherein a rotating electric motor is supported by the housing. A vertical output shaft extends within the housing and engages gears controlling a pair of flat platens enclosed above and on sides by the housing. The platens have lower surfaces with bonded sandpaper pads adapted to be in contact with a floor to be sanded. The vertical output shaft controls reciprocating movement of the platens linearly in a plane in opposite directions, so that the platens move toward and away from each other, thereby reducing little induced force or vibration transmitted to the housing.