Single-stage gear reduction output mechanism with a locking fork providing anti-back drive capability for automotive seat adjuster drives

An automotive seat adjuster drive comprising:

• a gear housing bracket;
• a gear housing extending from said gear housing bracket to define a cavity therein;
• an axle shaft disposed within said cavity of said gear housing and extending along an axis of rotation;
• said axle shaft being supported within said cavity of said gear housing such that said axle shaft is free to rotate about said axis of rotation;
• an eccentric carried on said axle shaft and including a first bore that is concentric with said axle shaft, a first bearing surface that is eccentric relative to said axle shaft, and a second bearing surface that is concentric with said axle shaft;
• an actuator rotatably coupled to eccentric for driving rotation of said eccentric about said axis of rotation of said axle shaft;
• said axle shaft extending through said first bore in said eccentric with a slip fit such that said eccentric is free to rotate relative to said axle shaft;
• a first gear carried on said axle shaft that is rotatably coupled to said axle shaft such that said first gear rotates with said axle shaft about said axis of rotation;
• a second gear carried on said first bearing surface of said eccentric and disposed in meshing engagement with said first gear;
• said second gear including a second bore and a centerline axis that extends co-axially through said second bore;
• said first bearing surface of said eccentric extending through said second bore in said second gear with a slip fit such that said eccentric is free to rotate relative to said second gear;
• said first gear and said second gear having a planetary arrangement where said centerline axis of said second gear is parallel to and spaced from said axis of rotation of said axle shaft;
• a locking plate disposed within said cavity of said gear housing and including a first slot cutout, a second slot cutout, and a third slot cutout;
• a support pin rigidly fixed in place relative to said axle shaft that is parallel to and spaced from said axis of rotation of said axle shaft and that extends through said first slot cutout in said locking plate;
• said second bearing surface of said eccentric extending through said second slot cutout in said locking plate where said second bearing surface of said eccentric and said support pin cooperate to support said locking plate within said cavity of said gear housing and limit movement of said locking plate relative to said gear housing to movement along a lateral axis that is transverse to said axis of rotation of said axle shaft;
• and
• said second gear including a first pin that is spaced from and parallel to said centerline axis of said second gear where said first pin extends through said third slot cutout in said locking plate and prevents said first gear from driving rotation of said second gear.

An automotive seat assembly comprising:

• a frame including two side plates and front and rear cross-members that extend across said frame between said side plates;
• a sector gear rotatably coupled with said rear cross-member that rotates with said rear cross-member;
• a gear housing bracket attached to one of said side plates of said frame;
• a gear housing extending from said gear housing bracket to define a cavity therein;
• an axle shaft disposed within said cavity of said gear housing and extending along an axis of rotation;
• said axle shaft being supported within said cavity of said gear housing such that said axle shaft is free to rotate about said axis of rotation;
• an output pinion rotatably coupled with said axle shaft that rotates with said axle shaft;
• said output pinion including pinion teeth that are meshingly engaged with said sector gear;
• an eccentric carried on said axle shaft and including a first bore that is concentric with said axle shaft, a first bearing surface that is eccentric relative to said axle shaft, and a second bearing surface that is concentric with said axle shaft;
• an actuator mounted to said gear housing and rotatably coupled to eccentric for driving rotation of said eccentric about said axis of rotation of said axle shaft;
• said axle shaft extending through said first bore in said eccentric with a slip fit such that said eccentric is free to rotate relative to said axle shaft;
• a first gear carried on said axle shaft that is rotatably coupled to said axle shaft such that said first gear rotates with said axle shaft about said axis of rotation;
• a second gear carried on said first bearing surface of said eccentric and disposed in meshing engagement with said first gear;
• said second gear including a second bore and a centerline axis that extends co-axially through said second bore;
• said first bearing surface of said eccentric extending through said second bore in said second gear with a slip fit such that said eccentric is free to rotate relative to said second gear;
• said first gear and said second gear having a planetary arrangement where said centerline axis of said second gear is parallel to and spaced from said axis of rotation of said axle shaft;
• a locking plate disposed within said cavity of said gear housing and including a first slot cutout, a second slot cutout, and a third slot cutout;
• a support pin rigidly fixed in place relative to said axle shaft that is parallel to and spaced from said axis of rotation of said axle shaft and that extends through said first slot cutout in said locking plate;
• said second bearing surface of said eccentric extending through said second slot cutout in said locking plate where said second bearing surface of said eccentric and said support pin cooperate to support said locking plate within said cavity of said gear housing and limit movement of said locking plate relative to said gear housing to movement along a lateral axis that is transverse to said axis of rotation of said axle shaft;
• and
• said second gear including a first pin that is spaced from and parallel to said centerline axis of said second gear where said first pin extends through said third slot cutout in said locking plate and prevents said first gear from driving rotation of said second gear.