US Patent 7316594 Wheel suspension and retraction system

A mechanism is provided by which the wheels of an amphibious vehicle are simultaneously retracted or protracted for switching between a land mode and a marine mode of operation. Each of a transversely spaced pair of wheels is supported by a horizontally arranged spring and damper combination acting on at least one suspension link. Each spring and damper combination is in turn supported by a movable anchor point, the position of which determines the extent of protraction or retraction of the associated wheel. The anchor points for the two wheels may be located at opposite ends of a rotatable rocker member, the rotational orientation of which is determined by an actuator taking the form of for example a hydraulic ram or electric motor.