| 摘要 |
<P>PROBLEM TO BE SOLVED: To supply fuel to a high-pressure passage and to reduce pressure by simple structure using a control valve. <P>SOLUTION: This fuel supply device comprises a plunger 14 for pressurizing an operation chamber 13 between a low-pressure passage 4 and a high-pressure passage 5, a first check valve 15 for preventing the reverse flow of fuel from the high-pressure passage 5 to the operation chamber 13, and a control valve 17 for switching connection/disconnection between the low-pressure passage 4 and the operation chamber 13. A bypass passage 21 for returning fuel from the high-pressure passage 5 to the low-pressure passage 4 is provided with a second check valve 22 for opening and closing the bypass passage 21 according to pressure in the operation chamber 13. At the supply of fuel, the control valve 17 is closed when the plunger 14 is raised to raise the pressure in the operation chamber, and fuel in the operation chamber 13 is pressurized and supplied to the high-pressure passage 5. At the reduction of the pressure, the control valve 17 is closed when the plunger 14 is lowered to reduce the pressure in the operation chamber so as to open the second check valve 22 by using the negative pressure in the operation chamber 13, and fuel is returned from the high-pressure passage 5 to the low-pressure passage 4 through the bypass passage 21. <P>COPYRIGHT: (C)2009,JPO&INPIT |
