An apparatus for converting rotary motion of a drive shaft of a motor disposed in a housing into oscillatory motion of a work piece, the motion converting apparatus comprising: a planetary gear assembly operatively connected to the motor for rotation of an output gear, the planetary gear assembly comprising: a carrier having opposite drive and driven surfaces, the carrier including: a cylindrical support axially extending from the drive surface, wherein the output gear axially extends from the cylindrical support, and a cylindrical distal end portion axially extending from the output gear and adapted to be rotatably received in an annular opening in the housing; a sun gear directly or indirectly driven by the motor; a plurality of planet gears mounted for rotation on the driven surface of the carrier, wherein the planet gears are arranged around the sun gear and at least some of the planet gears mesh with the sun gear; a bearing assembly positioned in the housing between peripheral surfaces of each of the cylindrical support and the cylindrical distal end portion of the carrier and the interior surface of the housing; and an orbit gear non-rotatably mounted in the housing, wherein the planet gears mounted on the carrier mesh with the orbit gear so that rotation, caused by the sun gear, of at least some of the planet gears relative to the carrier causes the carrier to rotate relative to the orbit gear; a drive gear meshing with the output gear at a periphery of the output gear, wherein the drive gear includes a drive pin eccentrically mounted on a face of the drive gear and projecting outwardly from the face of the drive gear; and a yoke having a cam slot for receiving the drive pin for reciprocation of the yoke by the drive pin upon rotation of the drive gear, wherein the yoke is operatively connected to the work piece. a planetary gear assembly operatively connected to the motor for rotation of an output gear, the planetary gear assembly comprising: a carrier having opposite drive and driven surfaces, the carrier including: a cylindrical support axially extending from the drive surface, wherein the output gear axially extends from the cylindrical support, and a cylindrical distal end portion axially extending from the output gear and adapted to be rotatably received in an annular opening in the housing; a sun gear directly or indirectly driven by the motor; a plurality of planet gears mounted for rotation on the driven surface of the carrier, wherein the planet gears are arranged around the sun gear and at least some of the planet gears mesh with the sun gear; a bearing assembly positioned in the housing between peripheral surfaces of each of the cylindrical support and the cylindrical distal end portion of the carrier and the interior surface of the housing; and an orbit gear non-rotatably mounted in the housing, wherein the planet gears mounted on the carrier mesh with the orbit gear so that rotation, caused by the sun gear, of at least some of the planet gears relative to the carrier causes the carrier to rotate relative to the orbit gear; a carrier having opposite drive and driven surfaces, the carrier including: a cylindrical support axially extending from the drive surface, wherein the output gear axially extends from the cylindrical support, and a cylindrical distal end portion axially extending from the output gear and adapted to be rotatably received in an annular opening in the housing; a cylindrical support axially extending from the drive surface, wherein the output gear axially extends from the cylindrical support, and a cylindrical distal end portion axially extending from the output gear and adapted to be rotatably received in an annular opening in the housing; a sun gear directly or indirectly driven by the motor; a plurality of planet gears mounted for rotation on the driven surface of the carrier, wherein the planet gears are arranged around the sun gear and at least some of the planet gears mesh with the sun gear; a bearing assembly positioned in the housing between peripheral surfaces of each of the cylindrical support and the cylindrical distal end portion of the carrier and the interior surface of the housing; and an orbit gear non-rotatably mounted in the housing, wherein the planet gears mounted on the carrier mesh with the orbit gear so that rotation, caused by the sun gear, of at least some of the planet gears relative to the carrier causes the carrier to rotate relative to the orbit gear; a drive gear meshing with the output gear at a periphery of the output gear, wherein the drive gear includes a drive pin eccentrically mounted on a face of the drive gear and projecting outwardly from the face of the drive gear; and a yoke having a cam slot for receiving the drive pin for reciprocation of the yoke by the drive pin upon rotation of the drive gear, wherein the yoke is operatively connected to the work piece.