Patent GB-1186672-A (GB)
Title: Improvements in Pivotal Suspension Arms
Inventor: HIRST ARCHIE JOHN
IPC: B60G7/02
Filed: 1966-04-21
Abstract: 1,186,672. Vehicle suspension. METALASTIK Ltd. 18 April, 1967 [21 April, 1966], No. 17419/66. Heading B7D. [Also in Division F2] A pivotal suspension arm, for vehicle wheels, includes a rubber spring and bearing assembly which provides adequate radial and axial stiffness and a rising load/deflection characteristic as well as a low overall height and which comprises a pair of similar rubber sandwich units 30, 31 each consisting of a rubber block 32 bonded, during a moulding operation, between opposed faces 33, 34 on a common metal attachment part 36 and attachment plates 35, the units, in the absence of a direct load, being symmetrically disposed in relation to an axis 40 which passes through the geomotric centre of the assembly, and being loaded in shear and compression. The opposing faces 33 of the part 36 are cylindrical, of large radius, and progressively recede from the faces 34 which are parallel. Ribs 39 on the flanges 38 of the part 36 allow the assembly to be torsionally preloaded by an amount equal to " kerb weight ", attachment holes (46), Fig. 3, not shown, being jig drilled, from each end of the assembly, in the ribs 39. An assembly is fitted into a boxsection trailing arm (T), Figs. 4, 5, not shown, which carries a live rear axle, not shown, bolts (4Oa) passing through side wall members (46b) and through the holes 46 and adequate clearance being provided within the box-section to allow for bulging of the rubber blades 32. Direct load, due to the vehicle weight, causes a small displacement of the axis 40 generally parallel to the faces 34. By inclining the plates 35 with respect to each other or, by making one of the rubber blocks stiffer than the other, the axis 40 may be brought to coincide with the geometrical centre. The faces 33, Fig. 2, may be flat. The assembly can be employed as an inboard bearing of any vehicle wheel suspension arm, or wishbone, where the angular travel is not too great and, to accommodate the large angular travel of such shorter suspension arms, the outer attachment parts (60), Fig. 6, not shown, are cylindrical and the central attachment part (61) presents convex cylindrical faces (65) and has bores (67) for attachment bolts. The faces (66) have their longitudinal axes eccentrically disposed in relation to the geometric centre axis (70) one on each side of the latter at (71) and (72). Similarly the faces (65) have their axes at (73), 74. The faces (65, 66) approximate closely to logarithmic spirals about the axis (70). In an installation, Fig. 13, the plates 60 are secured in an eye 82 in a transverse pivotal suspension arm 83 pivoted to an engine support 84, the inner part of the bearing assembly being secured to the support 84 through ferrules 85 positioned in the ends of centerbored holes 67. The wheel hub 91 of a vertical strut 90 is carried at the free end of the arm 83 on a king pin 92. In a modification the plates 60 may be provided with attachment flanges. In a suspension arrangement, Fig. 20, not shown, links (112, 113), pivoted respectively at the forward and rear ends to a chassis at (110, 111), are connected, at their inner ends respectively, to an eye member (115) and the inner part (61) of an assembly housing in the eye member (115) the latter being bolted to a wheel or axle which is supported by a similar suspension at its other end. A suspension, Fig. 21, not shown, includes two such arrangements. A disclaimer is made in respect of Specification 1,118,643.