| 摘要 |
The present invention involves a carbureted fuel system (34) for an internal combustion engine (10) for small utility implements. The engine includes a crankcase (28) with a cylinder bore (16). The crankcase rotatably supports a crankshaft (12) having a flywheel (18) and a magnet (20) disposed on an outer periphery of the flywheel. The crankshaft is also connected to a reciprocating piston (14) 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 (25) and an air inlet. The carburetor includes a mixing chamber (36) in which the fuel and air are mixed together and then introduced into the manifold (38) and eventually into the cylinder via a valve (40) for combustion therein. In communication with the main passage (23) of the carburetor is a secondary air inlet in which is disposed an air bleed device (32, 200), such as a solenoid or PZT (200) operated actuator, which is controlled by an electronic control unit (50). An induction coil (22) is disposed adjacent the flywheel and is coupled to the electronic control unit so that the rotation of the flywheel generates a pulse on the induction coil that is processed by the electronic control unit. Based upon the information derived from the electrical pulses generated by the induction coil, the electronic control unit activates the air bleed device to enrich or enlean the air-to-fuel mixture fed into the cylinder for combustion. In this manner emissions associated with the operation of the engine may be reduced. <IMAGE> |
