| 摘要 |
Hydraulic power-assisted steering mechanism comprises two steering valves 60, 60' having pressure chambers 21 in permanent communication with a steering motor 3. Pistons 62, 62' have throttle-openings 37, 37' into spring chambers 11, 11'. An actuator 2 comprises pre-control valves 43, 43'. A cut-out device comprises a pressure limiting valve 70, back pressure valves 68, 68' feed-back chambers 66, 66' and throttle-openings 64, 64'. An alternative mechanical cut-out device is also described. The steering pressure is proportional to the force applied to the actuator 2 up to a cut-out point, and then rises steeply, for example for parking. <IMAGE> |
