A ROTOR FOR AN AMPHIBIOUS VEHICLE AND AMPHIBIOUS VEHICLES PROVIDED THEREWITH

摘要

1360853 Amphibious vehicles; vehicle wheels J A KEARSEY 6 April 1972 [8 April 1971] 9164/71 Headings B7A B7V and B7C An amphibious vehicle is moved, on both water and land, by rotors 13, 15, 17 and 19, each of which comprises a pair of end discs 39 and 41 joined by rods which carry a flexible impermeable membrane 61. Air from a compressor 11 is fed to the space 75 inside the membrane 61 via hollow shafts 45. The pressure in the space 75 can be controlled from the vehicle cabin to vary the shapes of the concavities which the free portions of the membrane assume while underwater (Fig. 6) and thus to vary the propulsion characteristics of the rotor. Within each rotor an inflatable bag 57 is also inflated by the compressor 11 and improves the mechanical linkage between the discs 39 and 41. The bag 57 may be used to control rotor buoyancy if the pressure in space 75 is constant and in any case reduces the volume of space 75 to facilitate control of pressure in the latter. Retractable hydrofoils 21 and 23 are mounted behind the rotors and, by appropriate adjustment of their inclination, can be used to supplement the lift and forward thrust of the rotors. The rotor end discs are hollow and are divided by radial plates 47 into compartments which are filled with a polystyrene filler to aid buoyancy. The outer disc of each rotor contains an hydraulic motor 38 to rotate the rotor. Each end disc carries a tyre 71 (Fig. 3) for use during land travel. Each tyre is bolted to the disc rim and overlies the edge of the membrance 61 to hold it in place. The vehicle buoyancy may be provided solely by the rotors. Alternatively the buoyancy may be provided partly or wholly by hull displacement or by an air cushion. In the latter case, the cushion may be confined between lateral hulls and the rotors. The rotor end discs may be resilient so that they can partly conform to land contours. Steering may be effected by differential rotor speed and/ or pressure control. Alternatively, the rotors may be steerable. When rotors are not required to be buoyant, for example in the case of an amphibious submarine, they may be water filled. To ensure appropriate deformation of the membrane in this case, each rotor is divided by an internal plate across which a pump maintains a pressure difference. During travel on land, the membrane may be withdrawn for travel over hard surfaces or may be used to give partial support for the vehicle when travelling over soft surfaces. The rotors may have helically arranged tie rods, i.e. one end of each rod may be angularly advanced relative to the other end. This arrangement gives an improved ride where the tie rods themselves contact the ground to support part of the vehicle weight.