| 摘要 |
A driving and steering system for a vehicle having at least two propelling tracks or wheels driven by output shafts from within a housing containing respective planetary gear sets, each planetary gear set including a sun gear element, a planet gear-carrier element, and a ring gear element. A power-driven shaft between the planetary gear sets has driving engagement with both of the sun gear or the planet gear-carrier elements, and the respective output shafts are driven by the other one of the sun gear or planet gear-carrier elements. A steering shaft is operatively engaged with the ring gear elements to hold them against rotation for straight line propulsion of the vehicle or to rotate them in opposite directions for steering of the vehicle. The steering shaft is actuated by a steering wheel through the intermediary of a bi-directional fluid motor which is energized only when the steering wheel is turned in either direction to steer the vehicle and which is de-energized when turning of the steering wheel is stopped to thereby stop rotation of the steering shaft for continued straight line travel of the vehicle. Optionally, the steering shaft may be actuated by a bi-directional fluid motor which is energized when the steering wheel is turned in either direction from central straight travel position to steer the vehicle and which is de-energized when the steering wheel is returned to central straight travel position. |
