Steering gear
First Claim
1. An assembly for pivoting the steerable wheels of a vehicle upon manual rotation of a steering wheel, said assembly comprising:
- a member which is axially movable to effect turning movement of the steerable vehicle wheels;
ball screw and nut means for applying force to said member to move said member axially, said ball screw and nut means including;
thread means connected with said member, rotatable nut means circumscribing at least a portion of said thread means and ball means for transmitting forces between said nut means and said thread means;
an electric motor for rotating said nut means about the central axis of said member, said electric motor includinga stator for providing a magnetic field, and a rotor disposed in a coaxial relationship with said member and rotatable under the influence of the magnetic field from said stator to rotate said nut means relative to said thread means;
control means for energizing the stator of said electric motor to rotate said motor and nut means in response to rotation of the steering wheel; and
a rack and pinion gear set for applying force transmitted from the steering wheel to said member and for moving said member axially and imparting rotary motion to said nut means to turn the steerable vehicle wheels upon failure of said electric motor, said rack and pinion gear set includinga pinion gear rotatable with the steering wheel anda rack gear disposed in meshing engagement with said pinion gear and connected with said member.
1 Assignment
0 Petitions
Accused Products
Abstract
A steering gear for turning steerable wheels of a vehicle comprises a member movable in opposite directions. The member has first and second portions. The first portion comprises a rack having gear teeth extending transverse to the direction of movement of the member. A manually rotatable pinion engages the rack for applying a first force to the rack. An electric motor applies a second force to the second portion of the member. The electric motor encircles the member and rotates a ball nut. The ball nut cooperates with a screw portion of the member to effect linear movement of the member in response to actuation of the motor.
89 Citations
6 Claims
-
1. An assembly for pivoting the steerable wheels of a vehicle upon manual rotation of a steering wheel, said assembly comprising:
-
a member which is axially movable to effect turning movement of the steerable vehicle wheels; ball screw and nut means for applying force to said member to move said member axially, said ball screw and nut means including; thread means connected with said member, rotatable nut means circumscribing at least a portion of said thread means and ball means for transmitting forces between said nut means and said thread means; an electric motor for rotating said nut means about the central axis of said member, said electric motor including a stator for providing a magnetic field, and a rotor disposed in a coaxial relationship with said member and rotatable under the influence of the magnetic field from said stator to rotate said nut means relative to said thread means; control means for energizing the stator of said electric motor to rotate said motor and nut means in response to rotation of the steering wheel; and a rack and pinion gear set for applying force transmitted from the steering wheel to said member and for moving said member axially and imparting rotary motion to said nut means to turn the steerable vehicle wheels upon failure of said electric motor, said rack and pinion gear set including a pinion gear rotatable with the steering wheel and a rack gear disposed in meshing engagement with said pinion gear and connected with said member. - View Dependent Claims (2, 3, 4, 5, 6)
-
Specification