Abstract: A power steering apparatus (10) includes a first pump (24) which is continuously driven to supply fluid under pressure to a power steering motor assembly (18). A second pump (32) is driven by the engine (30) of the vehicle when a predetermined vehicle operating condition occurs. The predetermined vehicle operating condition may, if desired, be operation of the engine (30) of a vehicle at a speed which is less than a predetermined speed. A flow control valve (40) directs fluid flow from the first and second pumps to the power steering motor assembly (18) during operation of both pumps. A diverter valve (62) directs fluid from the first pump (24) along a fluid flow path which is spaced from the flow control valve (40) during operation of only the first pump. The first pump (24) may, if desired, be smaller than the second pump (32).

Abstract: An apparatus (10) for use in turning steerable vehicle wheels (12, 14) includes first and second piston and cylinder type hydraulic motors (32, 34) which are connected with a central portion of a vehicle. A steering control valve (24) is operable in response to manual rotation of a steering wheel (18) to effect extension and contraction of the first and second hydraulic motors. A rack and pinion steering gear (110, 114) may be connected with a piston rod (86) of one of the hydraulic motors (32). A secondary control valve (200) may be provided to effect operation of one of the hydraulic motors to a greater extent than the other hydraulic motor.

Abstract: An apparatus (10) for use in turning steerable vehicle wheels (14, 16) includes a hydraulic power steering motor (12). A pump (26) is operable to supply hydraulic fluid to the power steering motor (12). A gearset (50) is connected with the engine of the vehicle and the pump (26). The gearset (50) is operable to drive the pump at a first speed during turning of the steerable vehicle wheels (14, 16) at relatively low vehicle speeds. The gearset (50) is operable drive the pump at a second speed during turning of the steerable vehicle wheels at relatively high vehicle speeds. The second speed which is less than the first speed. The gearset is a differential gear mechanism.

Abstract: An apparatus (10) for use in turning steerable vehicle wheels (12,14) includes a connector member (28) which connects a first end portion (70) of the rack (66) with a first steerable vehicle wheel (14). A second end portion (72) of the rack (66) is spaced from the second steerable vehicle wheel (12) and is free of a connection with a member which extends between the second end portion of the rack and the second steerable vehicle wheel. A force transmitting member (32) extends between the steerable vehicle wheels (12,14) and extends through a hydraulic motor (42). Upon rotation of a steering wheel, a valve connected with a pinion gear (62) effects operation of the motor (42) to turn the steerable vehicle wheels (12,14).

Abstract: An apparatus (10) for helping to turn steerable wheels (12) of a vehicle comprises a hydraulic power-assisted steering gear (16). An electric motor (92) actuates the steering gear (16). A pump (84) supplies the steering gear (16) with hydraulic fluid. A vehicle speed sensor (102) senses vehicle speed and provides a vehicle speed signal. A controller (104) is responsive to the vehicle speed signal for controlling the pump (84). The controller (104) activates the pump (84) to supply hydraulic fluid to the steering gear (16) when the vehicle speed signal indicates a vehicle speed below a predetermined value and the controller (104) deactivating the pump (84) when the vehicle speed signal indicates a vehicle speed above the predetermined value.

Abstract: A ball joint assembly (10) comprises a socket (12) with a chamber (18), an opening extending through a first axial end (20) of the socket (12), and electrically conductive structure (60) closing the second axial end (22) of the socket (12). An electrically conductive ball stud (30) has a head portion (32) that is received in the chamber (18) and a shank portion (34) that extends through the opening. An electrically conductive bearing member (40) is received in the chamber (18) and provides an electrical connection between the structure (60) and the ball stud (30). An electrically non-conductive biasing member (50) is interposed between the structure (60) and the bearing member (40) and urges the bearing member away from the structure such that, in response to a predetermined amount of wear, the electrical connection between the structure (60) and the ball stud (30) is discontinued.

Abstract: A steering apparatus (10) for a vehicle having steerable road-engaging wheels comprises a rotatable steering wheel (11) and a sensor (12) which senses the rotational position of the steering wheel and generates a first signal corresponding to the sensed rotational position of the steering wheel (11). A first electric motor (14), when energized, resists rotation of the steering wheel (11). A second electric motor (20) is controlled by the signal generated by the sensor for sensing the rotational position of the steering wheel (11). A steering gear (130) is actuated by the second electric motor (20) to turn the steerable wheels of the vehicle. An electrical circuit (19) includes the first and second motors (14 and 20) in series.

Abstract: An apparatus (10) for helping to turn steerable wheels (12) of a vehicle comprises a hydraulic power-assisted steering gear (16). An electric motor (92) actuates the steering gear (16). A pump (84) supplies the steering gear (16) with hydraulic fluid. A vehicle speed sensor (102) senses vehicle speed and provides a vehicle speed signal. A controller (104) is responsive to the vehicle speed signal for controlling the pump (84). The controller (104) activates the pump (84) to supply hydraulic fluid to the steering gear (16) when the vehicle speed signal indicates a vehicle speed below a predetermined value and the controller (104) deactivating the pump (84) when the vehicle speed signal indicates a vehicle speed above the predetermined value.

Abstract: A steering apparatus (10) for turning steerable wheels of a vehicle having first and second sets (14 and 16) of steerable wheels comprises a first steering gear (22) actuatable, in response to rotation of a handwheel (110), to effect turning of the first set (14) of steerable wheels. The steering apparatus (10) also comprises second and third steering gears (24 and 26), each of which is independently actuatable to effect turning of the second set (16) of steerable wheels and thereby providing redundancy for turning of the second set (16) of steerable wheels. A sensor (112) senses a steering position of the first set (14) of steerable wheels and provides a steering signal indicative of the sensed steering position. A controller (114) receives the steering signal and, in response to the steering signal, controls actuation of the second and third steering gears (24 and 26).

Abstract: An apparatus (10) for helping to turn steerable wheels (12) of a vehicle comprises a hydraulic power-assisted steering gear (16). An electric motor (92) actuates the steering gear (16). A pump (84) supplies the steering gear (16) with hydraulic fluid. A vehicle speed sensor (102) senses vehicle speed and provides a vehicle speed signal. A controller (104) is responsive to the vehicle speed signal for controlling the pump (84). The controller (104) activates the pump (84) to supply hydraulic fluid to the steering gear (16) when the vehicle speed signal indicates a vehicle speed below a predetermined value and the controller (104) deactivating the pump (84) when the vehicle speed signal indicates a vehicle speed above the predetermined value.

Abstract: A ball joint assembly (10) comprises a socket (12) with a chamber (18), an opening extending through a first axial end (20) of the socket (12), and electrically conductive structure (60) closing the second axial end (22) of the socket (12). An electrically conductive ball stud (30) has a head portion (32) that is received in the chamber (18) and a shank portion (34) that extends through the opening. An electrically conductive bearing member (40) is received in the chamber (18) and provides an electrical connection between the structure (60) and the ball stud (30). An electrically non-conductive biasing member (50) is interposed between the structure (60) and the bearing member (40) and urges the bearing member away from the structure such that, in response to a predetermined amount of wear, the electrical connection between the structure (60) and the ball stud (30) is discontinued.

Abstract: A steering apparatus (10) for turning steerable wheels of a vehicle having first and second sets (14 and 16) of steerable wheels comprises a first steering gear (22) actuatable, in response to rotation of a handwheel (110), to effect turning of the first set (14) of steerable wheels. The steering apparatus (10) also comprises second and third steering gears (24 and 26), each of which is independently actuatable to effect turning of the second set (16) of steerable wheels and thereby providing redundancy for turning of the second set (16) of steerable wheels. A sensor (112) senses a steering position of the first set (14) of steerable wheels and provides a steering signal indicative of the sensed steering position. A controller (114) receives the steering signal and, in response to the steering signal, controls actuation of the second and third steering gears (24 and 26).

Abstract: A steering apparatus (10) for a vehicle having steerable road-engaging wheels comprises a rotatable steering wheel (11) and a sensor (12) which senses the rotational position of the steering wheel and generates a first signal corresponding to the sensed rotational position of the steering wheel (11). A first electric motor (14), when energized, resists rotation of the steering wheel (11). A second electric motor (20) is controlled by the signal generated by the sensor for sensing the rotational position of the steering wheel (11). A steering gear (130) is actuated by the second electric motor (20) to turn the steerable wheels of the vehicle. An electrical circuit (19) includes the first and second motors (14 and 20) in series.

Abstract: A method for controlling a steering apparatus (10) of a vehicle produces an error signal (128) by subtracting a hand wheel torque (118) and a column torque (126) from a desired operator torque (112) to be applied to a hand wheel (14) of the vehicle. A controller (102) receives at least one vehicle condition signal (106, 108, 110) and determines the desired operator torque (112). Inertia (116) and acceleration (120) of the hand wheel (14) of the vehicle are determined. A hand wheel torque (118) is calculated by multiplying the inertia (116) of the hand wheel (14) with the acceleration (120) of the hand wheel (14). The column torque (126) is determined by measuring torque across a torsion bar (50).

Abstract: A method for controlling a steering apparatus (10) of a vehicle produces an error signal (128) by subtracting a hand wheel torque (118) and a column torque (126) from a desired operator torque (112) to be applied to a hand wheel (14) of the vehicle. A controller (102) receives at least one vehicle condition signal (106, 108, 110) and determines the desired operator torque (112). Inertia (116) and acceleration (120) of the hand wheel (14) of the vehicle are determined. A hand wheel torque (118) is calculated by multiplying the inertia (116) of the hand wheel (14) with the acceleration (120) of the hand wheel (14). The column torque (126) is determined by measuring torque across a torsion bar (50).

Abstract: An apparatus for controlling a vehicle active suspension system having a plurality of actuatable hydraulic motors, each corner having a motor connecting the sprung mass with its associated unsprung mass. Each motor has an associated spool valve for connecting either of two expandable fluid chambers of said motor to a pump or reservoir. Each corner has an associated force sensor for sensing the force value between its associated unsprung mass and the sprung mass. An analog, closed force loop control circuit provides a valve control signal having a value functionally related to the difference between a sensed force value and a desired force value for a selected corner. The closed loop control circuit includes a variable gain amplifier for controlling the value of the valve control signal as a function of the frequency of variations in the difference between the sensed force value and the desired force value on the selected corner.

Abstract: An apparatus (10) and a method provide a signal (12) indicative of velocity of a mass (18). An acceleration sensor (64) senses acceleration of the mass (18) and provides an acceleration signal (66) indicative of the acceleration of the mass. A displacement sensor (70) senses displacement of the mass (18) and provides for a displacement signal (72) indicative of displacement of the mass. Two filters (68 and 74) operate upon the acceleration and displacement signals (66 and 72) respectively, and the filter outputs are summed to provide the velocity signal (12). In one example, an active suspension system (16) utilizes the velocity signal (12) to control relative movement between the mass (18), as a sprung mass, and an unsprung mass (20). The suspension system (16) includes a controller (54), which receives the velocity signal (12) and provides a control signal (56) utilizing the velocity signal.

Abstract: A self-centering motor (16) includes a piston (130) which is disposed in a housing (112) and is movable in opposite directions from a centered condition. A pair of centering members (160 and 162) are disposed in the housing (112) to effect movement between the piston (130) and the housing toward the centered condition upon the occurrence of a predetermined condition, such as failure of a pump (44) to supply fluid under pressure. The members (160 and 162) which effect movement of the piston (130) to the centered condition are normally disposed in an overlapping relationship which enables the motor (16) to have a compact construction. In one embodiment of the invention, the members (160 and 162) which effect movement between the piston (130) and the housing (112) toward the centered condition include an inner centering member (162) and a cylindrical outer centering member (160) which extends around the inner centering member.

Abstract: An apparatus (30) which controls the motion of a cab (12) of a vehicle relative to a frame of the vehicle includes a cab motion control motor (38). A pair of motor control valves (70 and 72) are provided to control fluid pressure conducted to the cab motion control motor (38). The motor control valves (70 and 72) are supplied with fluid under pressure by a power steering pump (22). The power steering pump (22) also provides fluid under pressure to a power steering motor (20) which is operable to turn steerable vehicle wheels (18).