| 摘要 |
PURPOSE:To automatically regulate acceleration fuel according to the load of an engine and to provide excellent acceleration, by a method wherein a leak fuel passage, branched from the discharge fuel passage of a pump chamber and leading to a float chamber, is installed, and a control valve is located to such branching part. CONSTITUTION:An accelerator pump device P has a pump body 9 secured to the bottom of a carburetter body 7 so that it holds the outer periphery of a pump diaphragm 8 between the nip formed by the carburetter body and the pump body, and a pump chamber 11 is formed between the pump diaphragm 8 and the pump body 9. The pump chamber 11 is communicated with a float chamber 14 through a fuel passage 13 and with an acceleation fuel nozzle 17 of a suction passage 16 through a discharge fuel passage 15. In which case, a leak fuel passage 26 leading to a float chamber 14 is branched halfway along the discharge fuel passage 15, and a control valve V is located to such branching part. The discharge fuel passage 15 is rendered effective with the aid of a control valve V only during operation of an engine, a communicating opening between the leak fuel passage and the discharge fuel passage 15 is decreased with an increase in an engine load. |
