Abstract: A worm shaft (46) has a first end section (52) and a second end section (54) extending from a worm section (50). A first drive system (98) is in driving engagement with the first end section (52) of the worm shaft (46), and a second drive system (104) is in driving engagement with the second end section (54) of the worm shaft (46) for redundantly steering a vehicle. The worm section (50) of the worm shaft (46) is disposed between the first drive system (98) disposed on the first end section (52) of the worm shaft (46) and the second drive system (104) disposed on the second end section (54) of the worm shaft (46). A lost motion connection (82) is disposed between an input shaft (76) and said worm shaft (46).

Abstract: A control assembly (20) for overcoming a rotational resistance required to activate supplementary steering force associated with conventional power steering systems. The control assembly (20) includes a shaft (26) subject to rotational resistance via a torsion bar (62). A valve assembly (22) has a first hydraulic circuit (76) that is interchangeable from an unassisted condition (36) to an assisted condition (34) for providing supplementary steering force to a steering gear after the rotational resistance of the torsion bar (22) is overcome by rotating the shaft (26). An actuator (38) includes a second hydraulic circuit (86) interchangeable from an unengaged condition (42) to an engaged condition (40) applying circumferential force on the shaft (26) to overcome the rotational resistance of the torsion bar (62) and rotate the shaft (26) from a non-rotated position thereby activating the supplementary force of the first hydraulic circuit (76).

Abstract: A worm shaft (46) has a first end section (52) and a second end section (54) extending from a worm section (50). A first drive system (98) is in driving engagement with the first end section (52) of the worm shaft (46), and a second drive system (104) is in driving engagement with the second end section (54) of the worm shaft (46) for redundantly steering a vehicle. The worm section (50) of the worm shaft (46) is disposed between the first drive system (98) disposed on the first end section (52) of the worm shaft (46) and the second drive system (104) disposed on the second end section (54) of the worm shaft (46). A lost motion connection (82) is disposed between an input shaft (76) and said worm shaft (46).

Abstract: A control assembly (20) for overcoming a rotational resistance required to activate supplementary steering force associated with conventional power steering systems. The control assembly (20) includes a shaft (26) subject to rotational resistance via a torsion bar (62). A valve assembly (22) has a first hydraulic circuit (76) that is interchangeable from an unassisted condition (36) to an assisted condition (34) for providing supplementary steering force to a steering gear after the rotational resistance of the torsion bar (22) is overcome by rotating the shaft (26). An actuator (38) includes a second hydraulic circuit (86) interchangeable from an unengaged condition (42) to an engaged condition (40) applying circumferential force on the shaft (26) to overcome the rotational resistance of the torsion bar (62) and rotate the shaft (26) from a non-rotated position thereby activating the supplementary force of the first hydraulic circuit (76).