The final step came when steam was introduced into the cylinder to drive the piston backward as well as forward, thereby increasing the speed of the engine and cutting its fuel consumption.
最后一步是将蒸汽引入气缸，使得活塞前后推动，从而提高了发动机的速度，降低了燃料消耗。
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The trigger wheel rotates with engine RPMs and causes the speed sensor, or pickup oil, to produce triggering voltage pulses that correspond to engine speed and piston position.
Reciprocating pumps convert rotary motion to linear motion. Pump speed in RPM determines the pumps output volume for any given combination of cylinder bore and piston stroke.