Abstract: Devices for adjustably controlling a flow of fluid through a common passage and through first and second auxiliary passages are disclosed. The flow control devices may be used for controlling the steering of a vehicle having independently controlled driven structures, such as wheels. Various other applications of these devices and related methods are also disclosed.

Abstract: A self-cleaning attachment for a rotary mower has a carrier member (26) supporting a flexible, linear element (25) radially spaced from the rotational axis of the blade at a level above the blade so the element rotates near the underside of the mower housing defining a narrow upper chamber where air pulses are concentrated to maintain the underside of the housing relatively clean of build-up. The carrier may have a plurality of elements in equally spaced relationship, the structure of which is such that the outer tips are supported above the blade when idle, and the inertial mass is low compared to the rotating mass of the blade such that there is relatively little rotational effect as the elements become worn. The attachment is retro-fittable to existing mowers without causing appreciable power loss or degrading the blade stopping capability below ANSI standards for residential lawn mowers.

Abstract: A self-propelled utility tractor having articulated steering, a standing operator, a turning radius near the rear wheel on the inside of a full turn, the radius of turn being not substantially longer than the wheel base, independent rear wheel brakes to assist in tight turns, a steering wheel for operating a steering linkage, an engine and transmission, centrally mounted with the engine below the transmission transmitting power by a jack shaft so the out put shaft of the engine extends down to power an attachment. Where the attachment is a mower deck, a rear discharge chute on the tractor deflects the clippings uniformly across the rear to avoid wind rowing. Flexible elements rotate above the mower blade to provide additional mulching and turbulent air flow and self-cleaning of the underside of the deck.