Patent ID: 7401677

Claim:
A steering system for a vehicle having first and second steerable wheels, said steering system comprising: an axle having first and second end portions which are suspended by springs and which support the first and second steerable wheels of the vehicle, said axle having an intermediate portion which at least partially defines a chamber through which a longitudinal central axis of said axle extends, said first steerable wheel being pivotally mounted on said first end portion of said axle for pivotal movement about a first pivot axis which extends transverse to the longitudinal central axis of said axle, said second steerable wheel being pivotally mounted on said second end portion of said axle for pivotal movement about a second pivot axis which extends transverse to the longitudinal central axis of said axle; a steering member having a longitudinal central axis, said steering member being supported in said chamber in said axle for movement along a linear path relative to said axle, said steering member having a screw thread portion disposed between first and second ends of said steering member; a ball nut associated with said screw thread portion of said steering member and disposed in said chamber in said axle; an electric motor connected with said axle; at least one drive member connected with said electric motor and said ball nut to rotate said ball nut to move said steering member in said chamber in said axle upon actuation of said electric motor; a takeoff assembly connected to said first end of said steering member and having a portion projecting from an opening in said intermediate portion of said axle, said takeoff assembly being movable with said steering member along the linear path upon rotation of said ball nut; first steering linkage connected with said projecting portion of said takeoff assembly and extending along an outer side of said axle to transmit movement from said takeoff assembly to said first steerable wheel upon movement of said steering member and said takeoff assembly along the linear path, said first steering linkage being pivotally connected to said first steerable wheel to effect pivotal movement of said first steerable wheel about said first pivot axis upon movement of said steering member and said takeoff assembly along the linear path; and second steering linkage connected with said projecting portion of said takeoff assembly and extending along the outer side of said axle to transmit movement of said takeoff assembly to said second steerable wheel upon movement of said steering member and said takeoff assembly along the linear path, said second steering linkage being pivotally connected to said second steerable wheel to effect pivotal movement of said second steerable wheel about said second pivot axis upon movement of said steering member and said takeoff assembly along the linear path.