| 摘要 |
PROBLEM TO BE SOLVED: To improve the high-speed responsiveness by providing a piezoelectric element of solid structure for driving a plunger and a bulkhead for isolating the piezoelectric element from fuel, and arranging a fuel inlet part to an injector in a position backward from the piezoelectric element when seen from the plunger. SOLUTION: A laminated type solid element is used as a piezoelectric element 11, the piezoelectric element 11 is supported by a movable member (damper) 16, and the piezoelectric element 11 and the movable member 16 are arranged in the area filled with high viscosity silicone oil, which is surrounded by inner pipes 12, 31 and a diaphragm (bulkhead) 15. Fuel is supplied from a fuel inlet part 33 arranged backward from the piezoelectric element 1 to the tip of an injector through a part between outer pipes 13, 32 forming the housing and the inner pipes 12, 31 and through a fuel through-hole 19. A plunger 14 is pressed onto the injector tip by the extending motion of the piezoelectric element 11 to close it, and the plunger 14 is further moved by the force of a spring 25 by the contracting motion of the piezoelectric element 1 to open it.
|
