GB348667A - Improvements in and relating to resilient shock absorbers - Google Patents

Abstract

348,667. Springs combined with screw mechanism. NAYLOR, E. J., Thuya Cottage, Harefield Road, Uxbridge, Middlesex. Dec. 10, 1929, No. 37898. [Classes 108 (ii) and 108 (iii).] A resilient connection, which may be applied to vehicle suspension systems, includes a differential screw in which the separate screws are reversible and have a minimum angle of 15‹. In the construction shown applied in Fig. 1 to an ordinary vehicle suspension system, a tubular member 34 connected to the axle slides vertically under the control of a helical spring 36 in a casing 35 connected to the vehicle frame. Vertical movements of the axle are transmitted to the helical spring 36 through a reduction gear constituted by a sleeve 39 having internal and external threads of different pitch. The outer threads engage the sleeve 34 and the inner threads a central non-rotatable block 38, the upper end of which engages the spring 36. The initial tension of the spring 36 may be adjusted by a screw 42, while buffer springs 40, 41 at the top and bottom of the casing limit the extreme movement. In the example shown, the outer screw has a pitch angle of 45‹ and the inner screw 30‹. In a modification the central block is integral with the casing 35 and the sleeve bears against the lower end of the spring 36 through a ball thrust bearing. In a further modification, Fig. 4, a sleeve 48 slides non-rotatably on a casing 46 and carries, on a buffer spring 50, a non-rotatable internally threaded sleeve 49 which meshes with the lower end of a sleeve 47, the upper larger end of which is provided with a thread of opposite hand engaging the casing 46. The sleeve 47 supports the upper member 46 by an outer mainspring 51 and composite subsidiary springs 52 which include several springs of different strength arranged in series so that they are compressed solid in succession. The screwed members may be carried resiliently in the main elements. The apparatus may be so mounted and adapted that it may be used in connection with the steering, braking and driving of motor vehicles. To reduce friction rollers may be arranged between the threads.