Abstract: The invention relates to a throttling valve comprising a fluid inlet (29) and a fluid outlet (27). The throttling valve is arranged to control a flux of a fluid stream flowing via a flow path from the fluid inlet (29) to the fluid outlet (27). The flow path comprises a plurality of openings (330) which, in use, create a pressure reduction over the throttling valve and thereby a cooling effect of the fluid. The openings (330) widen in a downstream direction.

Abstract: The present invention involves a carbureted fuel system for an internal combustion engine for small utility implements. The engine includes a crankcase with a cylinder bore. The crankcase rotatably supports a crankshaft having a flywheel and a magnet disposed on an outer periphery of the flywheel. The crankshaft is also connected to a reciprocating piston disposed in the cylinder bore. A cylinder head is attached to the crankcase over the cylinder bore, and a carburetor is disposed on the cylinder head. The carburetor is in communication with a fuel supply and an air inlet. The carburetor includes a mixing chamber in which the fuel and air are mixed together and then introduced into the manifold and eventually into the cylinder via a valve for combustion therein. In communication with the main passage of the carburetor is a secondary air inlet in which is disposed an air bleed device, such as a solenoid or PZT operated actuator, which is controlled by an electronic control unit.

Abstract: A vehicle control system embodying an engine driving the vehicle and, selectively, a power takeoff shaft. When the power takeoff shaft is being driven, a governor controls the speed of the engine. A device is provided for detecting the shaft speed and the engine will be slowed when the shaft speed is exceeded to protect element being driven by the power takeoff shaft in the event the governor fails.

Abstract: The calculation of an adjustment value, which is determined by the concentration of oxygen in the exhaust gas, the opening of a throttle valve provided in an intake air passage to the engine, the engine temperature, etc., is started every time a predetermined number of repeatedly produced start signals, the repetition rate of which corresponds to the rotational speed of the crankshaft, occur. A basic value for fuel supply, T.sub.p =k Q/N, is calculated from the engine operating parameters; the amount of flow of intake air into the engine, Q the rotational speed of the crankshaft, N, and a constant k, and adjusted according to the adjustment value to obtain a control output signal, in the vicinity of the next start signal after said predetermined number.