Patent GB-872555-A (GB)
Title: Vehicle axle suspensions
Inventor: HIRST ARCHIE JOHN
IPC: B60G11/23
Filed: 1959-03-17
Abstract: 872,555. Axle box mountings; rubber springs; road-vehicle suspension. METALASTIK Ltd. March 9, 1960 [March 17, 1959], No. 9290/59. Classes 103(6), 108(2) and 108(3). A railway vehicle axle box 10 Figs. 1 and 2, is supported from frame members or horn guides 13 on a bogie sole bar 12, by means of a pair of links 14, extending fore-and-aft of the vehicle on opposite sides of the box 10, the links being pivoted to the box and frame members through rubber bushes 16, 15, the arrangement being such that when the links are in the horizontal position shown, corresponding to tare load, they are in lengthwise compression, which gives rise to a negative stiffness effect when the vehicle is loaded. As shown the bushes 15, 16 have inner metal sleeves 19 which are expanded to pre-compress the rubber of the bushes. The sleeve of the bush 16 has keyed thereto at 20, a pair of pins 18 each pin 18 has a foot 22 to abut a vertical surface 24 on the axle box and a hook portion 28 to overlie and abut an inclined ledge 29 on the box 10. Similarly the sleeve of the bush 15 has keyed thereto a pair of pins 17 each having a foot 21 to abut a vertical surface 23 of a horn guide 13 and a hook portion 30 which underlies and abuts inclined surface 33 of a ledge 31 on a part 32, attached to the sole bar 12 and embracing the guide 13. The guides 13 are fixed to depending arms 42 of a U-shaped stirrup 43 forming part of the bogie frame 12. The parts 32 are carried by a cross member 45 which passes through a window 46 in the vertical web of the sole bar and has a central boss to receive a threaded stud 48 having a head 49 which engages a plate 50 secured to the bar 12. The parts 32 are also braced by transverse members 44. By adjusting the studs 48 the axle box 10 may be adjusted relative to the sole bar 12. A stirrup 51 connected with the box 10 by rods 57 passing through the sole bar, retains the box on the bogie when the latter is removed from the track. In the embodiment of Fig. 4, the axle casing 61 of a road vehicle is connected through a bracket 69 and rubber bush 70, with a vertical link 71 formed of two channel members 72, 73 bolted together with the interpositioning of packing pieces 74. Pins 75, 76 on the members 72, 73 are pivotally connected to link structures 77, 78 through rubber bushes. The link structures 77, 78 are also connected by rubber bushes with transverse pins 65, 66 mounted on the chassis side frame 60 and braced by brackets 67, 68 secured to transverse frame tubes 63, 64. Referring to Fig. 6, each link structure comprises bush assemblies 80, 81 carried at the ends of rigid T-section arms 83, 84 which are braced by straps 85. The bush 81 has an inner sleeve 95 for keying to a pin 75 or 76 and an outer sleeve 96 keyed at 99 to a sleeve 97 carried by the arms 83, 84. The bush 80 comprises mner and outer concentric bushes 89, 91 the inner sleeve 92 of the bush 91 being keyed to a pin 65 or 66 and its outer sleeve 93 keyed at 98 to the inner sleeve 90 of the bush 89. The outer sleeve 86 of the bush 89 is bolted to the arms 83, 84. The bushes are all pre-compressed. In the case of the bush assembly 80 the inner bush 91 provides most of the torsional flexibility whilst the outer bush 89 provides most of the radial flexibility. With reference to Fig. 4, the full-line positions of the links 77, 78 correspond with the full load position whilst the dotted-line positions correspond with tare load. At an intermediate position between those shown each link 77 or 78 is arranged so that there are no longitudinal forces acting therein and there is no torsion in the bushes. In the tare position the links will be compressed whilst in the full load position they will be in tension. The links are auxiliary to a conventional leaf spring suspension (not shown) and the torsion of the bushes as the links move from the intermediate position to the tare position oppose the leaf spring and as the links move from the intermediate position to the full load position the torsion of the bushes assists the leaf spring. In a modification described with reference to Fig. 8 (not shown) the concentric bush assembly may have an outer bush which is generally elliptical in shape with its major axis in the longitudinal axis of the link and an inner circular bush. Alternatively the outer bush may be circular and the inner bush generally elliptical in shape with its major axis disposed transverse to the link.