Abstract: A seal assembly for providing a seal between a cylindrical member and a bore formed in a housing, the housing and cylindrical member being rotatable relative to one another, the seal assembly being located within an annular groove formed in the cylindrical member and having an annular seal body of a plastics material having an outer axially extending circumferential face for sealing abutment with the bore and at least one radially extending end face for sealing abutment with a side face of the groove and a resilient ring member located in abutment with the inner axially extending circumferential face of the seal body for urging said outer circumferential face radially outward to maintain sealing abutment between said outer circumferential face and the bore during cooling of the seal and housing, the resilient ring member having an axial end face contiguous with or located in-board of said end face of the seal body, the resilient ring and seal body being interconnected so as to be axially movable in unison wit

Abstract: A rack and pinion apparatus comprising a toothed rack, the tops of the teeth of which lie in a common plane, the rack and pinion apparatus further comprising an anti-roll mechanism having a rack teeth engaging pad mounted to permit relative movement between the rack and teeth engaging means and so as to be in contact, at any given instant, with the tops of at least two rack teeth.

Abstract: A power assisted steering mechanism for a vehicle, the mechanism including electrically powered drive means for driving the steering mechanism, the drive means including a drive shaft having an input shaft portion drivingly connected to an output shaft portion by resilient means such that rotation of the input shaft portion causes relative rotational displacement between the input shaft portion and the output shaft portion in dependence on the load applied to the output shaft portion, sensor means arranged to produce signals in response to the direction and amount of relative displacement between the input and output shaft portions and an electric motor for driving said output shaft in response to the signals produced by the sensor means.

Abstract: The invention provides a closed center rotary valve and a power-assisted steering mechanism for a motor vehicle incorporating the rotary valve.The closed center rotary valve comprises cooperating relatively rotatable sleeve and core members having cooperating axially-extending grooves therein and means relatively biassing the members towards a neutral position.Said grooves comprise at least one inlet groove connectable to a source of fluid under pressure, a cylinder groove angularly spaced from the inlet groove on each side thereof and connectable to opposite sides of a double-acting piston-and-cylinder, and a return groove in overlapping relation with each of the cylinder grooves in the neutral position of the valve and connectable to a reservoir for the fluid under pressure, the inlet groove being closed from communication with the cylinder and return grooves in the neutral position of the valve.

Abstract: The invention provides a method of and apparatus for imparting a required metering form to the longitudinal outer edges of axially extending grooves of cylindrical rotor members of rotary valves by moving an impressing tool or tools having the required metering form thereon against a said edge or edges of a rotor member or members generally in the direction of a chord extending between a point on said edge and a similar point on an adjacent edge of the nearest adjacent groove so as to displace the material of the edge being worked away from the groove.

Abstract: A rotary valve in or for a power-assisted rack-and-pinion steering mechanism for a motor vehicle, the rotary valve comprising a valve sleeve, a rotor member rotatable within the valve sleeve, the rotor member and the valve sleeve each having axially extending grooves therein which cooperate to control the flow of fluid under pressure through the valve according to the angular disposition of the rotor member relative to the valve sleeve, and a torsion bar connecting the rotor member to the pinion of the rack-and-pinion steering mechanism, wherein the said pinion is cylindrical and is rigidly connected to the valve sleeve by means of an annular coupling member having an end portion which fits over an end portion of the pinion and has internal teeth which intermesh with the teeth of the pinion, the annular coupling member being brazed or otherwise bonded to both the pinion and to the valve sleeve.

Abstract: A power-assisted rack-and-pinion steering mechanism for a vehicle provided with a beam axle and semi-elliptical springs, the steering mechanism comprising double-acting piston-and-cylinder means having a piston rod opposite ends of which are provided with ball joints whereby the piston rod is connectable with the steerable road wheels of a vehicle, a toothed rack spaced radially of the piston rod and extending away from the piston rod beyond one end thereof, a pinion connectable with the steering control of a vehicle and in meshing engagement with the toothed rack, the pinion being located outside, not between, said ball joints, a connecting member connecting adjacent ends of the piston rod and toothed rack, the connecting member being rigidly connected to the piston rod and being pivotally connected to the toothed rack, and a bifurcation of said connecting member for restraining the toothed rack against pivotal movement about an axis normal to the axis of said pivotal connection.

Abstract: A ball and socket joint comprising a ball housing threaded into the socket using a screw-thread of one hand and an annular locking member threaded into the socket and into engagement with the ball housing using a screw-thread of the opposite hand, the annular locking member having an inwardly directed portion at least a part of which is deformed axially into at least one recess in the ball housing to prevent relative rotation between the locking member and the ball housing.