US Patent 7464620 Actuator

An actuator for an automotive seat that includes two main assemblies: (1) a motor assembly; and (2) a gearbox assembly. The gearbox assembly includes multiple stages of gear reduction and a dividing plate. In some embodiments, the gearbox assembly has a single-lead worm, a worm gear with a right-hand helix tooth direction, and a worm gear with a left-hand helix tooth direction. The worm gears are driven by the single-lead worm. The single-lead worm has two ends, one end has a right-hand tooth helix direction, and the other end has a left hand helix direction.