GB631834A - Improvements in resilient suspension means for vehicles - Google Patents

Abstract

631,834. Vehicle suspensions; shockabsorbers. DUNLOP RUBBER CO., Ltd., and SEDDON, R. M. May 10, 1947, No. 12696. [Classes 108 (ii) and 108 (iii)] [Also in Group XXXI] In a resilient suspension means adapted to act in compression, two coaxial tubular resilient members 61, 61a contained within two telescopic members 45, 50 surround interengaging guide members 57, 58, while a piston 62 is disposed between the adjacent ends of the resilient members to form two chambers of variable volume; air can flow relatively freely from one of these chambers, but its return thereto is restricted. The tubes 45, 50 are respectively closed by plugs 46, 53, to which are attached the guide means 57, 58, a sliding bush 59 serving as an abutment ' for the resilient column 61. To prevent contact between the guide members and the resilient columns, which are formed of rubber or like resilient material, the former may be surrounded by a helical spring 68, or the bore of each disc comprising the column may be made tub-shaped. The abutting ends of the columns 61, 61a hold between them the piston comprising a cupwasher 64, in the crown of which is a small hole 65. On compression, air can escape freely from the upper tube 45 past this washer and pass to atmosphere through a hole 66 in the lower tube. Rebound is, however, damped as air can only return to the tube 45, through the small hole 65. Two opposed cup-washers may be used, in which case a valve is provided in the wall of the tube 45 to control air flow. The damping effect may be va ried by making this valve adjustable, or by placing the piston washer nearer one end of the telescoping members. Where, as in the case of a motor cycle front fork, two elements are connected in parallel relationship by transverse tubes 41, 42, holes coinciding with opposite ends of one of the bridging tubes may be drilled in the walls of the sleeves 45 and a single valve be provided, either on the tube or the wall of a sleeve 45, to control air flow in both elements. The rubber discs may be reinforced by bonding metal or fabric elements to their end faces; or they may be replaced by a single, or a set of, cylindrical tubes. The guide means may comprise a rod and tube, as shown, or inter-engaging slotted members. The spring may be of streamline shape in cross-section, and. if an elliptical shape is used, a set of guide members is provided at each focus.