| 摘要 |
PROBLEM TO BE SOLVED: To obtain good startability without fuel vapor jetting out of an injector even under a condition where fuel vapor is easily generated in a fuel return-less condition. SOLUTION: A fuel return line 8 is connected to a downstream side of a fuel gallery 5 including the injector 2 via a pressure leak valve unit 7, intake pipe vacuum pressure generated during engine operation is introduced to a vacuum chamber 16, a second fuel chamber 15b and a third fuel chamber 15 c are communicated by a change over valve element 22 via a diaphragm 17, fuel introduced from fuel pre-return line 25 communicating to a downstream side of the fuel gallery 5 is led to the third fuel chamber 15c. Since a second temperature sensitive operation valve part 31 provided in the third fuel chamber 15c opens when fuel temperature gets close to the vapor generation temperature, the valve is closed to form the return-less condition when fuel temperature is at the vapor generation temperature or less, and valve is opened and fuel in the fuel galleries 4, 5 is circulated to prevent generation of fuel vapor when fuel temperature gets close to the vapor generation temperature. COPYRIGHT: (C)2006,JPO&NCIPI
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