Patent GB-985066-A (GB)
IPC: F16J1/16
Filed: 1962-11-08
Abstract: 985,066. Connecting rod assemblies. M. JUSTINIEN, and F. DE CHABOT. Nov. 8, 1962 [Nov. 17, 1961; July 3, 1962], No. 42317/62. Heading F2T. [Also in Division F1] In order to automatically adjust the compression ratio of an I.C. engine the piston is attached to the connecting rod or crank-shaft by a pin constituted by one or more elongated elastic elements yieldingly mounted in a bore formed in one end of the connecting rod. In Fig. 1, the pin comprises a pair of centrally concaved spring blades 2 held fast at their ends in housings 3 which may be fixed or radially adjustable and are mounted in rings 4 slidable within bores p<SP>1</SP> in the bosses of a piston to allow for elongation in length of the blades as combustion of the gases occur in the engine cylinder, the blades thereby also acting to damp out the shocks produced. A cylindrical bush 6 rotatable within the connecting rod end has convex surfaces engaging the outer corresponding surfaces of the blades. In a modification, the ends of the blades are fitted in rings engaging inner part spherical surfaces in the piston bosses forming rotula-type joints. In Fig. 8, blades 26 held at their ends in convexly-shaped rectangular bores in rings 28 rotatable inside the piston bosses are separated from each other by a shorter blade 27 held in position by shaped buffer members 31. Washers 29 formed with oil passages abut against the pin. The blades 26 may have an arcuate cross-section. In an alternative construction, a rectilinear upper blade is spaced from a lower incurved blade by a centrally and axially arranged buffer member. In Fig. 12 the pin is constituted by a number of super-imposed blades of equal or varying thickness and has a circular crosssection decreasing in diameter from its centre towards its ends. Rotation of the blades relative to the connecting rod is prevented by the medial blades 40c, Fig. 13, engaging in grooves B<SP>1</SP>. In Fig. 15 the thicker outer blades 44 are provided at 44a with a cylindrical bearing surface smaller than the breadth of the top end of the connecting rod or a ring fitted therein. Rotation of the blades is prevented by a key 45 between one or both of the outer blades and the connecting rod. The blades may also be keyed as at 46 to the rings 41 which may revolve inside the piston bosses. The outer blades may be given a concave shape at 44C between their bearing surfaces 44a and their bearing surfaces in the rings 41. In a modification, the thickness of the inner blades also varies in the same manner as the outer blades. In Fig. 23, the thickness of the blades 48 decreases outwardly and their ends are receded from the ends of the pin and the blades 49 may have uniform or, as shown, non-uniform thickness. The ends of the pin may have a frusto-conical wedging engagement with the rings 41 or with a cylindrical bearing surface inside said rings. In Fig. 4, the pin is constituted by an assembly of elastic rods, e.g. of metal, which may have the same or different cross-sectional shapes and sizes. The outer rods 15 are circumferentially disposed around steel rollers or balls 16. Central rods 18, 19 arranged annularly inside the rods 15 may all have their ends abutting against the rollers or balls 16 or, as shown, the rods 18 are circumferentially spaced around rollers or balls 17 against which the end of the rods 19 abut. In another embodiment the pin comprises a number of concentrically arranged rods, the central rods being longer and engaging within the piston bosses and the outer peripheral rods being shorter and engaging only within the connecting rod end and being held at their ends by collars. The rings or bushes inside the connecting rod or the piston bosses for engaging the spring blades or rods may be made of synthetic rubber.