Patent GB-576484-A (GB)
Title: Improvements relating to amphibian vehicles
IPC: B60F3/00
Filed: 1943-12-13
Abstract: 576,484. Land and water motor vehicles. JENNINGS, H. W. K. (Amphibian Car Corporation). Dec. 13, 1943, No. 20835. [Classes 79 (ii) and 79 (v)] [Also in Group XXXIII] An amphibian vehicle comprises a propelling engine located within a water-tight hull and connectible to fore and aft differential driving axles, the ends of which each pivotally carry cased-in transmissions to road wheels, the casings being resiliently mounted to cushion road shocks and the wheels of one or both axles being steerable by manually-operated means within the hull. In the construction shown in Figs. 1 and 2, the water-tight'hull or body 15 is mounted on wheels 20, 21 which are independently sprung by means of longitudinal lever arms 45 and coil springs 70, the front wheels 20 being steered, and all the wheels being driven from an engine 37 which also drives the propeller 24, when the vehicle is afloat, from a take-off device 102 in the gear-box 100. The drive to the front wheels may be disconnected at will, and all the wheels may be steerable. The propeller 24 and rudder 131 are carried by a bracket 132 connected to the hull by tie rods 134 pivoted at 135, Fig. 8, so that the bracket can be raised and the propeller and rudder housed in a recess 25 in the hull when the vehicle is on land. For this purpose the bracket is raised and lowered by a fluid-pressure cylinder 140 pivoted to the hull and having its piston connected by a bellcrank lever 136 and link 137 to the bracket. When the propeller has been raised, the upper arm of the bell-crank passes the dead-centre position. The propeller shaft 121 is univerallyjointed at 125 in line with the pivots 135 so as not to interfere with the raising and lowering of the propeller. The engine 37 drives front and rear differential axles 40, 41 through gearbox 100, chain gearing contained in a casing. 102 and forwardly and rearwardly extending shafts 103 driving the differential gears 42, 43. A clutch 105 is provided in the drive to the front axle so that this can be disconnected when desired. The axle casings 40, 41 are mounted on the hull 15, and the road wheels are carried by arms or casings 45, Fig. 5, pivoted in bearings 54 on the hull coaxial with the axle casings. The differential axle shafts 64 drive the road wheel shafts 65 through chain gearing 63 in the arms 45. The movements of the arms are controlled by springs 70, Fig. 4, mounted between seats 82, 83 fixed respectively to rods 74 fixed to the hull and sleeves 81 which slide on extensions of the rods and are connected by ball joints 76 to wheel-carrying members 71 fixed to the arms. In the case of the steering wheel 20 shown in Fig. 4, the member 71 is the steering knuckle, and the wheel is driven through a universal joint 66 actuated in the steering pivot axis. A resilient buffer 86 on each spring seat 83 limits the upward movement of the arm by bearing against a flange 87 on a rod 80 connected by a resilient cup member 78 to the rod 74 fixed to the hull. The road wheels may be so mounted that they may be drawn upwards into recesses 18, 19 in the hull when the vehicle is on the water. For this purpose a hydraulic cylinder 177, Fig. 9, may be pivoted to the hull at 180, its pistonrod 178 being jointed at 179 to the wheel axle housing 172 connected by an arm 170 to the hull. The angular position of the arm is adjusted by admitting and exhausting liquid to and from the cylinder by a pipe 182. Spring means may be provided between the parts 172, 178 or the parts 177, 181, the latter being a pocket formed in the hull 174 to receive the end of the hydraulic cylinder. Alternatively, spring means may be incorporated in the cylinder itself, and may be pneumatic as in ordinary oleo-pneumatic struts or shockabsorbers.. In a modification, Fig. 10 (not shown), the arm is controlled by a handoperated screw passing through a nut fixed in the hull and connected at its lower end by a coil spring to the wheel-axle housing. A flexible non-resilient strap also connects the lower end of the screw to the housing, so that when the screw rises it draws the housing upwards without having to unload the spring completely. A drum or pulley may be fixed to the outer side of anv road wheel so that a rope secured to ari anchorage and wound on the drum can be used to draw the vehicle off soft ground. Steering.-The steering arms 72 on the front wheel steering knuckles are connected by drag links 99, Figs. 1 and 2, to bell-crank levers 97 mounted on pivots just inside the hull, the inner ends of these levers being connected by a track rod 96 operated by the steering hand' wheel 93 through the steering-gear 94 and an arm 95. The apertures in the hull through which the outer arms of the levers 97 pass are sealed by flexible rubber or like sleeves. The rear wheels may be simultaneously or independently steered. Controlling.-The change-speed gear 100 is controlled by means of a gear lever 109 having a lower end 112 connected to the gear-shifting fork 108 by the linkwork shown in Fig. 7. In this arrangement the lever 112 and the fork 108 are respectively pivoted to bell-crank levers 115, 116 having pivots which slide in fixed slotted brackets 113, 114, the other ends of the bell-cranks being connected together by a link 118. Thus the fork 108 copies the movements of the lever 112. Each road wheel is provided with a brake drum 144, Fig. 4, and the brake on each wheel may be separately locked in the "on" position. For this purpose the brakes are preferably hydraulic and applied by a pedal 148, Fig. 6, and a master cylinder 147 connected by separate valves 150 and conduits 149 to the brake cylinders 145. The valves 150 are normally open, and when the pedal is depressed all the brakes are applied ; if any valve 150 now is closed, the corresponding brake is held on. This ensures that if one of the wheels, when the vehicle is afloat, makes contact with the ground before the others, this wheel can be driven by locking the other wheel on the same differential axle.