Patent attributes
The carburetor prevents an air-fuel mixture from becoming excessively lean and prevents a fuel pressure from becoming unstable, thereby making it possible to stably supply a fuel to an engine, in a diaphragm-type carburetor with a pressure regulator. A diaphragm-type carburetor includes a fuel pump using a pulsation pressure generated in a crank chamber of an engine or an intake pipe as a driving force, and a metering chamber having a diaphragm and a lever mechanism and provided with fuel at a desired constant pressure. The diaphragm-type carburetor includes a bubble discharge path connecting the metering chamber to other predetermined discharge portions and with a check valve in each of an inlet side and an outlet side. A bubble removing pump is connected to the bubble discharge path, withdraws the bubble to the bubble discharge path from the metering chamber in conjunction with a closing or opening operation of a throttle shaft by a driver or operator and discharging the withdrawn bubble to the discharge portion in conjunction with an opening or closing operation of the throttle shaft.