US Patent 7143999 Accelerating apparatus of carburetor

To inhibit an after burn phenomenon, an accelerating apparatus (P) is sectioned into a pump chamber (23) and a pressure receiving chamber (24) by a partition body (20), an acceleration fuel intake path (25) and an acceleration fuel discharge path (28) are open to the pump chamber (23), and a fuel discharge path (30b) is open to a float chamber (8), a negative pressure introducing path (30a) is open to the pressure receiving chamber (24), a pump spring (31) is provided compressedly in the pressure receiving chamber (24), and a valve body (34) is formed by a jet opening and closing valve portion (34a) opening and closing an opening portion (6a) of a main fuel jet (6) when an engine operates and stops respectively by a solenoid apparatus (S), and a discharge path opening and closing valve portion (34b) opening and closing the fuel discharge path (30b) when an engine stops and operates respectively, and synchronously moves with a movable core (17) of the solenoid apparatus (S).