Abstract: An apparatus for use in turning steerable vehicle wheels includes a steering column having a pinion connected with a vehicle steering wheel such that rotation of the steering wheel results in rotation of the pinion. An electrically powered steering unit includes an electric motor having a first output shaft rotatable about an axis. A first planetary gear stage has a first gear reduction ratio and is driven by the first output shaft. A second planetary gear stage is driven by the first planetary gear stage and the pinion and has a second gear reduction ratio different from the first gear reduction ratio. A second output shaft is driven by the second planetary gear stage and coupled to the steerable wheels such that rotation of the second output shaft affects steering of the vehicle wheels.

Abstract: An apparatus for use in turning steerable vehicle wheels includes a rotatable shaft that is rotatable relative to the vehicle to effect turning movement of the steerable vehicle wheels. A ball nut assembly is connected with an externally threaded portion of the rotatable shaft. The ball nut assembly moves axially relative to the rotatable shaft upon rotation of the rotatable shaft relative to the ball nut assembly. A steering member is connected to the ball nut assembly and at least one steerable vehicle wheel. The steering member moves with the ball nut assembly relative to the shaft. An electrical motor is connected with the rotatable shaft. The motor is operable to effect rotation of the rotatable shaft relative to the ball nut assembly to turn the steerable vehicle wheels.

Abstract: An apparatus for use in turning steerable vehicle wheels includes a steering column having a pinion connected with a vehicle steering wheel such that rotation of the steering wheel results in rotation of the pinion. An electrically powered steering unit includes an electric motor having a first output shaft rotatable about an axis. A first planetary gear stage has a first gear reduction ratio and is driven by the first output shaft. A second planetary gear stage is driven by the first planetary gear stage and the pinion and has a second gear reduction ratio different from the first gear reduction ratio. A second output shaft is driven by the second planetary gear stage and coupled to the steerable wheels such that rotation of the second output shaft affects steering of the vehicle wheels.

Abstract: A steering gear includes a housing defining a chamber. A piston divides the chamber into first and second chamber portions. The piston is moveable along a linear axis relative to the housing upon pressurization of fluid in one of the first and second chamber portions. A pressure relief vents pressurized fluid from one of the first and second chamber portions to one other of the first and second chamber portions upon movement of the piston to a predetermined position. The pressure relief assembly includes a first valve at a first end of the pressure relief assembly and a second valve at a second end of the pressure relief assembly. The pressure relief assembly is axially movable relative to the piston to adjust the position of the first valve and the second valve relative to the piston.

Abstract: A pressure relief valve for a fluid power assist steering system. The valve includes a housing and a spool disposed in the housing. The spool defines a cavity and has a first end and a second end. The spool is movable in the housing to limit an output pressure of the pump. A poppet seat is secured to the second end of the spool. A poppet is disposed in the cavity. A poppet spring biases the poppet into engagement with the poppet seat. A set screw is received in the first end of the spool. The set screw is rotatable relative to the spool to adjust a compression level of the poppet spring.

Abstract: A pressure relief valve for a fluid power assist steering system. The valve includes a housing and a spool disposed in the housing. The spool defines a cavity and has a first end and a second end. The spool is movable in the housing to limit an output pressure of the pump. A poppet seat is secured to the second end of the spool. A poppet is disposed in the cavity. A poppet spring biases the poppet into engagement with the poppet seat. A set screw is received in the first end of the spool. The set screw is rotatable relative to the spool to adjust a compression level of the poppet spring.

Abstract: A steering gear includes a housing defining a chamber. A piston divides the chamber into first and second chamber portions. The piston is moveable along a linear axis relative to the housing upon pressurization of fluid in one of the first and second chamber portions. A pressure relief vents pressurized fluid from one of the first and second chamber portions to one other of the first and second chamber portions upon movement of the piston to a predetermined position. The pressure relief assembly includes a first valve at a first end of the pressure relief assembly and a second valve at a second end of the pressure relief assembly. The pressure relief assembly is axially movable relative to the piston to adjust the position of the first valve and the second valve relative to the piston.