| 摘要 |
1,150,521. Controlling vehicle suspension height. MIDLAND-ROSS CORP. 4 Jan., 1967 [21 Jan., 1966], No. 496/67. Heading B7D. [Also in Division F2] A suspension levelling system in a vehicle having a sprung mass supported on an unsprung mass by springs 36 comprises supplementary air springs 26 within the springs 36, a pump 14 connected to the air springs 26, control means 24 connected between the pump 14 and the air springs 26 and comprising means for controlling operation of the pump 14 and of an exhaust valve 40 for exhausting the air springs 26, and a height-sensing switch 46 connected between the sprung and unsprung masses and the control means 24 to cause the pump 14 to be actuated or the exhaust valve 40 to be opened when the distance between the sprung and unsprung masses is less or greater than a predetermined amount. The pump 14 is driven by an electric motor 12 connected through a relay 16 and the ignition switch 18 to the vehicle battery 10. An arm 48 linked to the differential housing 50 actuates the height-sensing switch 46 through hydraulic damping and torque limiting means arranged such that rapid suspension movements during normal travel do not actuate the switch 46 but sustained variations in suspension height due to changes in loading actuate the switch 46 either to energize the relay 16 which operates the pump 14 or to energize a solenoid 20 which opens the exhaust valve 40. The valve 40 includes a valve element 114 which is connected to an armature 102 and closes an exhaust vent 116 from a passage 96 joining an outlet 98 which is connected to the air springs 26 to an inlet 92 which is connected to the pump 14 and provided with an elastomeric non-return valve 80. A sensing piston 82 sealed by a diaphragm 134 is displaceable against progressive spring-loading 156, 162 by the pressure in the passage 96 to actuate micro-switches 42, 44 which prevent operation of the pump 14 or opening of the exhaust valve respectively should the air spring pressure be above or below predetermined maximum and minimum values. |
