Amphibious vehicle transmission

Abstract

An amphibious vehicle has retractable road wheels to allow planing over water. Power to the road wheels is disconnected automatically as the wheels are retracted. This may be achieved through a cable attached to a suspension rocker arm to disconnect a dog clutch attached to the input shaft of a differential as the wheels are retracted; and vice versa. The system may be fitted to a steered axle or to any suitable retractable suspension system.

1 . An amphibious vehicle having a planing surface, comprising:
 a prime mover;   land propulsion means;   marine propulsion means;   transmission means for transmitting power generated by the prime mover to the land and/or marine propulsion means; and   retractable suspension means capable of retracting and protracting the land propulsion means, wherein the land propulsion means is automatically decoupled by the transmission means when retracted by the retractable suspension means and wherein the land propulsion means is retracted to a position above said planing surface.   
     
     
         2 . An amphibious vehicle as claimed in  claim 1 , wherein the land propulsion means is automatically coupled by the transmission means when protracted by the retractable suspension means. 
     
     
         3 . An amphibious vehicle as claimed in  claim 2 , wherein the transmission means is mechanically connected to the retractable suspension means and the automatic coupling and decoupling of the land propulsion means is effected by physical movement of the retractable suspension means. 
     
     
         4 . (canceled) 
     
     
         5 . An amphibious vehicle as claimed in  claim 3 , wherein the mechanical connection between the transmission means and the retractable suspension means is a mechanical linkage. 
     
     
         6 . An amphibious vehicle as claimed in  claim 1 , wherein the transmission means comprises a dog clutch to effect coupling and decoupling of the land propulsion means. 
     
     
         7 . (canceled) 
     
     
         8 . (canceled) 
     
     
         9 . An amphibious vehicle as claimed in  claim 1 , wherein the prime mover is an internal combustion engine. 
     
     
         10 . An amphibious vehicle as claimed in  claim 1 , wherein the land propulsion means comprises road wheels. 
     
     
         11 . An amphibious vehicle as claimed in  claim 1 , wherein the land propulsion means comprises tracks. 
     
     
         12 . An amphibious vehicle as claimed in  claim 1 , wherein the marine propulsion means comprises a jet drive. 
     
     
         13 . An amphibious vehicle as claimed in  claim 1 , wherein the marine propulsion means comprises a screw propeller. 
     
     
         14 . An amphibious vehicle as claimed in  claim 1 , wherein the transmission means comprises a transfer case. 
     
     
         15 . An amphibious vehicle as claimed in  claim 1 , wherein the transmission means comprises a continuously variable transmission. 
     
     
         16 . An amphibious vehicle as claimed in  claim 1 , wherein the transmission means comprises a differential. 
     
     
         17 . An amphibious vehicle as claimed in  claim 1 , which is capable of planing when operating in marine mode. 
     
     
         18 . An amphibious vehicle as claimed in  claim 1 , wherein the land propulsion means is retractable above the static water line. 
     
     
         19 . An amphibious vehicle having a planing surface, comprising:
 a prime mover;   land propulsion means;   marine propulsion means;   a transmission for transmitting power generated from the prime mover to the land and/or marine propulsion means; and   a retractable suspension capable of retracting and protracting the land propulsion means, wherein the land propulsion means is retractable to a position above said planing surface and protractable to a position outboard of said planing surface, wherein:   the land propulsion means is automatically decoupled from the transmission when retracted by the retractable suspension;   the land propulsion means is automatically coupled to the transmission when protracted by the retractable suspension; and   the transmission is connected to the retractable suspension and the automatic coupling and decoupling of the land propulsion means is effected by physical movement of the retractable suspension.   
     
     
         20 . (canceled) 
     
     
         21 . An amphibious vehicle as claimed in  claim 19 , wherein the connection between the transmission and the retractable suspension comprises a mechanical linkage. 
     
     
         22 . An amphibious vehicle as claimed in  claim 19 , wherein the transmission comprises a dog clutch to effect coupling and decoupling of the land propulsion means. 
     
     
         23 . (canceled) 
     
     
         24 . (canceled) 
     
     
         25 . (canceled) 
     
     
         26 . (canceled) 
     
     
         27 . (canceled) 
     
     
         28 . (canceled) 
     
     
         29 . An amphibious vehicle, comprising:
 a prime mover;   land propulsion means;   marine propulsion means;   transmission means for transmitting power generated by the prime mover to the land and/or marine propulsion means; and retractable suspension means capable of retracting and protracting the land propulsion means, wherein the land propulsion means is automatically decoupled when retracted by means of a return spring.   
     
     
         30 . An amphibious vehicle, comprising:
 a prime mover;   land propulsion means;   marine propulsion means;   transmission means for transmitting power generated by the prime mover to the land and/or marine propulsion means; and   retractable suspension means capable of retracting and protracting the land propulsion means, wherein the land propulsion means is automatically decoupled by the transmission means when retracted by the retractable suspension means wherein the transmission and the retractable suspension are interlinked by a push-pull cable.