A vehicle steering gear apparatus comprises a pinion shaft in mesh with a rack, the pinion shaft being connectable to a steering wheel and the rack to a tie rod of a steering mechanism. The pinion shaft is supported at one end by a bearing that permits pivotal movement of the pinion shaft thereabout, and at its other end the pinion shaft is supported by a pair of bearings in a tube for axial, slidable movement. A spring acts on the tube between the pair of bearings to urge the pinion into pressure contact with the rack.
Rack and pinion assemblies employ a bearing assembly which is provided for rotatably mounting the pinion member in a housing member, the bearing assembly comprising three generally annular bearing elements which substantially encircle the pinion member. A first of the bearing elements is carried by one of the pinion or housing members and the second and third of the bearing elements are carried in an axially disposed relationship by the other of these members. The first element has a first bearing surface which engages axially between and slidably abuts substantially complementary second and third bearing surfaces of the second and third elements, respectively. The area of abutment between the respective surfaces extends both radially and axially so that the abutment restrains both radial and axial displacement of the first bearing element relative to the other two. The bearing assembly may be mounted in the rack and pinion assembly on a piecemeal basis, or may advantageously be provided as a pre-formed, pre-loaded unit whereby loading adjustments do not depend upon the skill of an operator during assembly of the rack and pinion.
A rack and pinion gear system in a gear casing for vehicle steering has a spring biased rack against the pinion at one side of the pinion to maintain pinion engagement with the rack. On the other side of the pinion is a generally semicircular bracing bushing encompasssing the pinion and slightly spaced therefrom to brace the pinion in event of bending due to operational stresses. The bracing bushing is carried for support against the gear casing and secured in any suitable manner or may be cast as part of it.
The pinion of a rack and pinion steering mechanism is assembled in a case by means of two bearings mounted on two bearing portions at each end of the pinion which are integral parts of the pinion. The bearings are capable of acting as two axial abutments for the pinion. One of the bearings is a cup acting as a smooth bearing. Longitudinally extending lubricating grooves are provided in the bearing portion within the cup. These grooves are extensions of the spare between roots of the gear teeth of the pinion and are machined by causing the tooth cutter to continue beyond the pinion and thereby cut the grooves in the bearing portion.
Rack and pinion assemblies especially for automotive steering gear with a spring biased plastics yoke slidably supporting the rack bar in a pinion housing to hold the toothed rack portion of the rack bar in fully meshed engagement with the pinion teeth. The pinion housing has a cylindrical bore slidably supporting circumferentially spaced bearing portions of the plastics yoke with an interference fit and the yoke has a recessed head embracing the side of the rack bar opposite the pinion equipped with lubricant storage chambers and a passageway connects the bottom of the recess with the housing chamber underlying the head.
A rack and pinion steering apparatus is provided with a compression spring mechanism bearing against the rack and urging the rack into engagement with a pinion connected to the steering wheel. The compressing spring mechanism is maintained against the pinion with a self-adjusting mechanism for removing play resulting from wear.
