| 摘要 |
A Diesel engine distributor-type injection pump has a vane pump (3) providing fuel under pressure to an injection pump system formed by two pistons (17) pressed towards each other by a cam track (26) to provide fuel under injection pressure to fuel injection plug connectors (28, 29) when the radial position of a duct (27) in the bore of the rotating shaft (2) matches a connecting duct (28) of a respective injection outlet. To provide for precise timing of fuel being injected, pressurized fuel is drained under control of a slider valve (FIG. 1: 38, 39; FIG. 2: 72, 74) connected through a communicating duct (32, 42, 71) to the slider valve. The slider valve is operated by a piezoelectric positioning element (FIG. 1: 61; FIG. 2: 76) which moves the spool (74, 39) of the slider valve; in one embodiment (FIG. 1), the piezoelectric element operates a piston (53) having a substantially larger diameter than the end faces of the spool (39) to provide for excursion amplification; in another embodiment (FIGS. 2, 4-8), the piezoelectric elements are bending elements and thus provide for larger excursion.
|
