摘要 |
Power assistance means for a rack and pinion steering gear includes a main rack and pinion steering gear (1) mounted on which is an auxiliary rack and pinion unit (9). The unit (9) includes an auxiliary rack bar (11), the rack of which engages with an auxiliary pinion in an auxiliary housing (10). The auxiliary pinion (12) is rotatable by an electric motor (23) in the housing (10) to drive the auxiliary rack bar (11). The housing (10) is bolted through brackets (14) to the housing (2a) of the main gear (1) while the auxiliary rack bar is coupled through a bracket (16) to the rack bar of the main gear (1). The electric motor (23) is controlled by a switch (27) in the steering input (7) to the pinion of the main steering gear (1) so that when the main rack bar is driven by rotation of the main pinion, the switch (27) is actuated to energise the electric motor and drive the auxiliary rack bar (11) in a sense appropriate to assist the displacement of the main rack bar. |