Abstract: A ball joint including a socket defining a chamber and having an opening. The ball joint also includes a ball stud having a ball portion and a shank portion. The ball portion is located in the chamber of the socket. The shank portion of the ball stud projects through the opening in the socket. The chamber has a shape generally conforming to the shape of the ball portion of the ball stud. Electrorheological fluid is interposed between the ball portion of the ball stud and the socket for resisting relative movement between the ball stud and socket. The viscosity of the electrorheological fluid is variable as a function of the magnitude of an electric field applied thereto to vary the resistance to relative movement between the ball stud and the socket. The electric field applied to the electrorheological fluid is controlled to control the viscosity of the electrorheological fluid and thereby control the relative movement between the ball stud and the socket.

Abstract: A method and apparatus is disclosed for nullifying electrical offsets present in an output signal from a torsion sensing device. The apparatus includes a detection circuit for outputting an electrical signal when a change between a no applied torque condition and an applied torque condition occurs in a member whose torsion is being monitored. A sample and hold circuit measures the output signal from the torsion sensing device, the sample and hold circuit being triggered in response to the detection circuit. A differencing circuit subtracts the output of the sample and hold circuit from a "zero torque" reference value and outputs an electrical signal having a value indicative of the difference therebetween. An offset compensating circuit is electrically connected to the output of the differencing circuit and to the torsion sensing device and outputs a modified torsion sensing signal having a value that varies as a function of the applied torque offset by the value of the output of the differencing circuit.

Abstract: An auxiliary drive circuit is disclosed for an electric, power assist steering system including an actuatable switching device which, when actuated, provides an auxiliary electrical path between a source of electrical energy and a mechanically actuatable reversing switch assembly for applying electrical power to energize an electric assist motor. The actuatable switching device in the auxiliary drive circuit is electrically connected in parallel to an actuatable switching device in a main drive circuit. A detector circuit monitors the operation of the main drive circuit and the output signal from a torque sensor. Upon detection of applied steering torque greater than a predetermined value and that the main drive circuit is not operating, the detector circuit outputs an electrical signal indicative thereof. A latching element latches the output of the detector circuit to actuate the actuatable switching device in the auxiliary drive circuit.

Abstract: An apparatus for connection between relatively movable parts. The apparatus includes a variable volume chamber having a first portion for connection with one of the parts and a second portion for connection with another of the parts. The chamber has fluid therein for resisting movement of the parts relative to each other. A valve controls the fluid flow from the chamber to a location at which the fluid does not resist relative movement of the parts. The valve includes a valve member movable from a first position to provide fluid communication between the chamber and the location. An electroviscous fluid control device resists movement of the valve member form the first position.

Abstract: A power assist steering system in which electrical power to drive the electric assist motor is selectively provided from either the alternator or the battery depending upon the vehicle speed and applied steering torque. An electronic control unit controls the output voltage from the alternator by controlling current through the alternator field coil.

Abstract: A steering apparatus is disclosed having a direction control valve for directing pressurized fluid to a hydraulic, power steering motor in a steerable vehicle. A piston in the hydraulic motor is mechanically connected to an operator steering wheel and to the vehicle wheels. Manual turning of the steering wheel effects initial piston movement and steering of the vehicle wheels. Upon initiation of a steering maneuver by manual operation of the steering wheel of the vehicle, piston movement causes the hydraulic motor to produce a pressure differential signal. The direction control valve responds to the pressure signal from the hydraulic motor and directs pressurized fluid from the power steering pump to the side of the hydraulic motor that is lower in fluid pressure.

Abstract: The invention provides an apparatus for controlling a power assist steering system of the type having an electric assist motor connected to a steering member such as a rack and a steering shaft including first and second coaxial shaft sections rotatable with respect to each other and connected by an elastic member. One of the shaft sections is coupled to the hand wheel and the other to the steering member. A cam operated, reversing switch is coupled across the first and second shaft sections. A drive circuit and the electric assist motor are connected to the reversing switch. A control circuit measures the relative rotation between the two shaft sections and controls the drive circuit. Relative rotation of the two steering shaft sections mechanically controls the reversing switch.

Abstract: An apparatus for turning a steerable vehicle wheel includes a pump assembly which is connected with a reservoir through an inlet valve. Upon rotation of a steering wheel, the inlet valve is actuated to allow fluid to flow from the reservoir to the pump assembly at a rate which varies as a function in variations in the speed of rotation in the steering wheel or the torque applied to the steering wheel. The output from the pump assembly is conducted to a directional control valve which is actuated upon initial rotation of the steering wheel to direct fluid flow to the power steering motor to effect turning movement of the steerable vehicle wheel in a desired direction. The rate at which the power steering motor turns the steerable wheel is determined by the extent to which the inlet valve is opened and is independent of the directional control valve.

Abstract: An improved method and apparatus for sensing relative movement between a pair of members includes a pair of parts which cooperate to provide an electrical signal upon relative movement between the members. One of these parts may be a Hall effect device and the other part may be a pair of magnets. In order to accurately position the Hall effect device and the magnets relative to each, they are mounted on a substrate or base. The portion of the substrate upon which the magnets are disposed is connected with one of the members. The Hall effect device is disposed on a portion of the substrate which is connected with the other member. Once the substrate has been connected with the two members, it is separated to enable the members to be easily moved relative to each other.

Abstract: An improved pump assembly includes a plurality of pumping elements which rotate with a rotor and engage an inner surface of a cam ring to define pumping chambers which hold liquid and/or air. As the pumping chambers move along an inlet arc, liquid flows through an orifice to the chambers. The orifice restricts the rate of flow of liquid to the pumping chambers to a flow rate which is insufficient to fill the chambers with liquid during high speed rotation of the rotor. As the pumping chambers move along an outlet arc which has a constant slope toward the rotor, the volume of each pumping chamber is decreased. When the fluid pressure in the pumping chamber exceeds a pump discharge pressure, one of a series of a check valves opens and fluid is discharged from the pumping chamber.

Abstract: In a fuel control system for a fuel injected internal combustion engine, fuel is pumped from a tank by a cheek plate unloading pump to the fuel rail which supplies the fuel injectors. The delivery pressure of the pump is controlled by a microprocessor which receives inputs from a number of sensors of engine operating variables. The microprocessor generates a control signal which controls the pump output pressure by actuating a solenoid-type linear actuator. The solenoid has an actuator rod which positions a spool in a control valve which regulates the pressure in a cavity behind the cheek plate in response to the control signal. If there is no control signal from the microprocessor, a spring moves the actuator rod to a position where it partially obstructs a passage through which the pump output flows. The partial obstruction or constriction creates a pressure drop which is proportional to the speed at which the pump is driven by the engine.

Abstract: A pump includes a rotor, a cam encircling said rotor and means for effecting relative rotation of the cam and rotor about an axis. A plurality of vanes are carried by the rotor and engage the cam to define pumping pockets which expand and contract on rotation of the rotor. A check plate is movable along the rotational axis to communicate expanding and contracting pumping pockets. There is a cavity on one side of the cheek plate, and a fluid passage conducts fluid pressure into the cavity which fluid pressure biases the cheek plate into a position blocking the flow of fluid from the contracting pumping pockets to the expanding pumping pockets. The pump also includes a servo valve for venting the pressure in the cavity to thereby control the flow of fluid between the contracting and expanding pumping pockets. A fluid passage in the cheek plate receives flow from the contracting pockets. The passage has a portion directing flow from the contracting pumping pockets radially inwardly of the cheek plate.

Abstract: A pump includes a rotor, a cam encircling said rotor and means for effecting relative rotation of the cam and rotor about an axis. A plurality of vanes are carried by the rotor and engage the cam to define pumping pockets which expand and contract on rotation of the rotor. A cheek plate is movable along the rotational axis to communicate expanding and contracting pumping pockets. There is a cavity on one side of the cheek plate, and a fluid passage conducts fluid pressure into the cavity which fluid pressure biases the cheek plate into a position blocking the flow of fluid from the contracting pumping pockets to the expanding pumping pockets. The pump also includes a servo valve for venting the pressure in the cavity to thereby control the flow of fluid between the contracting and expanding pumping pockets. A fluid passage in the cheek plate receives flow from the contracting pockets. The passage has a portion directing flow from the contracting pumping pockets radially inwardly of the cheek plate.

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.

Abstract: A pump has an inlet, an outlet, and a fluid displacement mechanism operable to pump fluid from the inlet to the outlet. A cheek plate in the pump is movable to control a flow of fluid from the outlet back to the inlet and thereby to vary the fluid flow to a hydraulic system supplied by the pump. Acting on different and unequal surface areas of the cheek plate are two fluid pressure forces. One fluid pressure force is provided by fluid pressure in a cheek plate control chamber. The force acts with a spring biasing force to bias the cheek plate into a position blocking the flow of fluid from the outlet back to the inlet. The second fluid pressure force acts on the cheek plate against the spring force and the first fluid pressure force. A first orifice communicates the pump outlet with the hydraulic system, a second orifice communicates the system with the control chamber, and a third orifice communicates the control chamber with the pump inlet.

Abstract: An air compressor including a motor, a motor housing, a piston assembly and a piston housing is disclosed. A bracket is located between the motor housing and the piston housing. The piston assembly includes pistons which reciprocate within sleeves upon rotation of a cam driven by the motor. The sleeves are received in U-shaped recesses in the piston housing. The open end of the U-shaped recesses are closed by the bracket. The bracket has tangs which act as springs to urge the sleeves firmly into the housing. The tangs accommodate variations in the dimensions of the housing and the sleeves, as well as provide contact with the sleeves for heat transfer.

Abstract: A pump for pumping low viscosity fuels has a cam defining a pumping chamber bore wall. A plurality of slippers define pumping pockets located within the bore wall. The slippers are rotated through inlet arcs and through outlet arcs. A pair of orifices of predetermined diameter are located in the respective inlet arcs and communicate with each pumping pocket at a location radially inwardly of the slippers. Each orifice is circular in cross-section and has a diameter within the range of 0.067 inches to 0.076 inches. Each orifice diameter is such that pump noise restricted and the pump has a relatively high inlet vacuum.

Abstract: An improved method and apparatus is provided to control the rate at which fuel is supplied to an engine by a fuel pump. The fuel pump has an output pressure which varies with pump operating speed in accordance with different curves of a series of curves. In order to determine which curve of the series of curves is representative of the manner in which the fuel pump output varies with pump speed at one time, the fuel pump operating speed and output pressure are simultaneously sensed to determine a point on an initial curve. The fuel pump operating speed is subsequently varied in accordance with the initial curve to provide a desired variation in fuel pump output to the engine. The fuel pump operating speed and output pressure are periodically simultaneously sensed to determine if the fuel pump output still varies in accordance with the initial curve or has changed to a second curve of the series of curves.

Abstract: An improved pump and motor assembly is utilized to regulate a flow of fuel to an internal combustion engine. All of the fluid connections to the pump are connected with one end of the assembly. The pump and motor are both enclosed within a one-piece casing having a tubular side wall which is integrally formed with an end wall. The end section to which all of the fluid connections for the pump are made, is connected across the open end of the tubular side wall. To provide for the removal of vapor bubbles from the fuel, fuel supplied under pressure from the tank flows through an inlet cavity which circumscribes the pump and has an axial extent which is equal to the length of the pump. In addition, a screen at the inlet of the pump itself blocks the flow of vapor bubbles from the inlet cavity to the pump. The forces applied against opposite sides of the moving components of the pump by the inlet fluid are substantially balanced.

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.