| 摘要 |
PURPOSE:To obtain a carburetor having high response performance by introducing the negative pressure of a negative-pressure source into a diaphragm chamber for operating the slidable piston of a variable venturi type carburetor according to the operation state of a throttle valve. CONSTITUTION:A slidable piston 2 installed on the upstream of the throttle valve 7 of a carburetor 1 introduces the negative pressure in a venturi 3 on the downstream of the piston into a diaphragm chamber 4 through a hole 2a, and is moved vertically in correspondence with the negative pressure, and supplies fuel between a needle 6 and a nozzle 5. When the throttle valve 7 is highly opened, especially it is sharply opened to a high opening degree, a selector valve 12 is operated to introduce the negative pressure in a tank 10 in which the negative pressure on the downstream of the throttle valve 7 is stored through a check valve 9, into the diaphragm chamber 4, and the piston 2 is compulsorily moved vertically, and the response performance in the transient operation of an engine can be improved. |
