| 摘要 |
<p>1,254,174. Vehicle level-control systems. V. LANGEN, [trading as LANGEN & CO.]. 20 Jan., 1969, No. 3131/69. Heading B7D. [Also in Division F2] In a vehicle level-control system comprising a valve 6 operated by a linkage 7 in response to variation of the distance between the sprung and unsprung masses of the vehicle in order to connect a pressure chamber 3 in a strut 4 to either a source 8 of pressure fluid or to a reservoir 9, or to block said connections when the vehicle is at the desired level, the valve 6 comprises a screw threaded spool 13 disposed in a bore 11 having a pin 22 engaging the screw thread 21 on the spool so that rotation of the valve spool 13 by the linkage 7 causes axial movement thereof to effect said connections. The valve spool 13 has a reduced diameter portion 16 adjacent an inlet P from the pressure source 8, a second reduced diameter portion 17 adjacent an exhaust T to the reservoir 9, and a land 15 adjacent an annular groove 18 in the bore 11 connected to the strut 4 via an outlet 19. When the vehicle is at the desired level the land 15 blocks the groove 18 from the bore 11. The flow of pressure fluid through the valve 6 is restricted by two further lands 19, 20 on the spool 13. 'In a second embodiment (Fig. 3) the spool has an axially fixed part (26) connected to the linkage and rotatably connected to an axially movable part (25) constructed as described above. In a third embodiment (Fig. 4) the bore has a screw threaded enlarged portion (34) adjacent the linkage 7 and a screw threaded guide member (36) is received in this portion (34) and is selectively rotatable by a second linkage (39), the guide member (36) carrying a pin (22<SP>1</SP>) which engages the screw thread on the spool 13, and the pitch of the two screw threads being different. Thus the vehicle level can be selectively predetermined. In a fourth embodiment (Fig. 5) a guide member (42) is axially fixed in an enlarged portion (40) of the bore 11 and carries a pin (22) co-operating with the screw threaded spool.</p> |
