Definition: Invented by British engineer James Atkinson, the Atkinson Cycle is one in which the stroke of the piston can vary in length across the four cycles in a four-stroke internal combustion engine. Typically, the length of the stroke during the power cycle is increased to promote efficiency; however, because this can come at the expense of a shorter intake stroke, there is some loss of power—for this reason, this type of engine design is best suited for use in a hybrid system where the electric motor can compensate for these power losses.
Pronunciation: at-kin-suhn sahy-kuhl
Examples:Toyota employs an Atkinson Cycle engine in the Prius hybrid car.
What is a Hybrid Vehicle?
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