PURPOSE: To set fuel-air ratio small at low load time and large at high load time to improve acceleration by providing an auxiliary fuel jet provided in addition to a main fuel jet, fuel control units and a diaphragm pump.
CONSTITUTION: An auxiliary fuel jet 106 provided in addition to a main fuel jet 8 is provided as a passage for supplying fuel to a main nozzle 9 of a carburetor. Fuel control units 201, 202 for controlling a fuel amount, supplied to the auxiliary fuel jet 106, associated with a position of a throttle 212 and a diaphragm pump for supplying fuel pressure-governed to these fuel control units 201, 202 are provided. Since the auxiliary fuel jet 106 is opened when an opening of the throttle 212 is increased, for instance, at high load time, fuel is supplied from the diaphragm pump to the main nozzle 9. In this way, the fuel amount is increased by the amount of the auxiliary fuel jet 106, and an output of improving acceleration of an engine can be ensured by increasing fuel-air ratio.
KAWAHARA YOSHITAKA
NAKATANI YOSHIHIDE
