Word forms: (plural) change-speed gearboxes
(Automotive engineering: Vehicle components, Engine, transmission, and exhaust) A change-speed gearbox is a set of movable or constant gears which allows the speed ratio between input and output shafts to be changed either manually or automatically. ▶ gearbox
⇒ An overspeed facility is provided through a step-up change-speed gearbox. ⇒ A front-mounted engine drives the rear wheels through a shaft and differential, controlled
through a friction clutch and change-speed gearbox. ⇒ The rest of the reduction can be obtained by means of the change-speed gearbox, which is interposed between the clutch and the final drive.
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