GB708071A - Improvements relating to pneumatic suspensions for vehicles - Google Patents

Abstract

708,071. Spring suspensions; pneumatic springs. NALLINGER, F. May 31, 1951 [Nov. 12, 1948], No. 12975/51. Classes 108(2) and 108(3) In a pneumatic vehicle suspension of the kind in which for maintaining the vehicle superstructure in a predetermined mean position, the pressure of compressed air in pneumatic springs of the piston and cylinder type is increased or reduced in dependence upon vehicle loading to such an extent that the springs are constantly maintained, against the loading, in the same mean position, there is in the mean position of the suspension, a continuous flow of compressed air through the pressure chamber of a pneumatic spring in which the air pressure is maintained or varied, under the control, by the relative movement of the piston of the spring, of a throttling point through which the air flows, and wherein the pneumatic spring co-operates with a pneumatic shock absorber, acting by air compression or air displacement. In the arrangement shown, in which piston 5 is pivotally connected to an axle 3 and is slidable in a cylinder 1 fixed to a chassis member 2. the cylinder is connected to a compressed air supply through a non-return valve 7, and is provided with an escape port 9 to atmosphere which remains uncovered bv the piston in the mean position shown. The lower end of the cylinder is closed and communicates with atmosphere through one or more throttling apertures 11 and 12. The escape port and apertures open into a jacket 15 concentric with the cylinder which is pr�- vided with an air filter 16 and is itself open to atmosphere. In a modification (Fig. 2, not shown) the lower end of the cylinder communicates with atmosphere through a bore in the lower end of the piston rod. In all cases the escape port or ports may be controlled in dependence upon the position of the piston by mechanical, electrical, hydraulic or pneumatic means. The spring may be combined with any other type of vehicle springing and with independent or rigid axle suspension systems.