| 摘要 |
A fuel injection pump having a mechanically adjustable servo valve for controlling the timing of the pumping event is disclosed. A pivoted lever has one end which engages the spring seat of a timing control plunger servo valve which is also subjected to a speed related hydraulic signal and another end in the form of a bimetal strip which engages a cam clamped on the throttle shaft to pivot the lever according to the rotational position of the shaft. The profile of the cam is such as to retard the timing of the pumping stroke when the charge delivered by the pump is increased to delay pressure built up in the pump so that injection pressure in the associated nozzle is reached at a scheduled crankshaft angle regardless of variations in speed and load on the engine. A heater for the bimetal strip is provided to shift the servo spring seat to change the timing of injection upon demand or automatically under a prescribed engine operation condition. In one embodiment, the bimetal provides 3 DEG -4 DEG more advance when the engine is cold to compensate for the delayed ignition of the fuel.
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