NEGATIVE PRESSURE TYPE FUEL SUPPLY DEVICE

摘要

PROBLEM TO BE SOLVED: To automatically reset a discharge pressure of a fuel pump when it is lowered to a specified value or less in a negative pressure type fuel supply device. SOLUTION: A pump chamber P is determined by a pump diaphragm 3 and a left side surface 1A of a pump main body 1, while a pulsative pressure chamber A is determined by the pump diaphragm 3 and a first cover 2. First and second fuel chambers F1, F2 are determined by a damper diaphragm 5 and a right side surface 1C of the pump main body 1. A damper chamber D are determined by the damper diaphragm 5 and a second cover 4. A third fuel chamber F3 is determined by a regular diaphragm 7 and an upper side surface 1G of the pump main body 1. A spring chamber S is determined by the regular diaphragm 7 and a fourth cover 6. An accumulation chamber C is determined by an accumulation diaphragm 16 and the right side surface 1C of the pump main body 1. An atmospheric chamber E is determined by the accumulation diaphragm 16 and a third cover 15. The accumulation chamber C is communicated with the third fuel chamber F3 through a seventh flow passage G7.