Vehicle drive transmission and steering system

Drive transmission and steering apparatus for a vehicle, wherein:

• the apparatus includes a gearbox housing;
• the apparatus includes an engine-shaft, which is arranged to receive motive power from an engine of the vehicle;
• the apparatus includes left and right wheel-shafts, which are arranged for transmitting motive power respectively to left and right road-wheels of the vehicle;
• the apparatus includes independently operable left and right steer-brakes, which are effective, when operated, to retard rotation of the respective wheel-shafts;
• the apparatus includes left and right wheel-differentials, having respective left and right wheel-sun-, wheel-planet-, and wheel-ring-gears;
• the left and right wheel-planet-gears are carried on respective left and right wheel-spiders;
• the left wheel-spider is unitary with the left wheel-shaft, and the right wheel-spider is unitary with the right wheel-shaft;
• the wheel-ring includes a wheel-drive-gear, which is in a fixed-ratio relationship with the engine-shaft;
• the apparatus includes a steer-differential, having a steer-diff-housing, and having left and right steer-shafts, and the structure of the steer-differential is such that the steer-shafts can rotate at different speeds;
• the left steer-shaft includes a left steer-wheel-gear, and the right steer-shaft includes a right steer-wheel-gear;
• the left wheel-sun-gear is in fixed-ratio relationship with the left steer-wheel-gear, and the right wheel-sun-gear is in fixed-ratio relationship with the right steer-wheel-gear;
• the left steer-wheel-gear is in fixed-ratio relationship with the left wheel-steer-gear, and the right steer-wheel-gear is in fixed-ratio relationship with the right wheel-steer-gear;
• the left and right wheel-ring-gears are components of a common wheel-ring, in which are formed the left and right wheel-ring-gears.