Generators info

1. REDIRECTContinuously variable transmission

The Continuously Variable Transmission (CVT) is a transmission in which the ratio of the rotational speeds of two shafts, as the input shaft and output shaft of a vehicle or other machine, can be varied continuously within a given range, providing an infinite number of possible ratios.

The Continuously Variable Transmission (CVT) should not be confused with the Infinitely Variable Transmission (IVT). The IVT is a specific type of CVT that has an infinite range of input/output ratios in addition to its infinite number of possible ratios; this qualification for the IVT implies that its range of ratios includes a zero output/input ratio that can be continuously approached from a defined ‘higher’ ratio. A zero output implies an infinite input, which can be continuously approached from a given finite input value with an IVT. [Note: remember that so-called ‘low’ gears are a reference to low ratios of output/input which have high input/output ratios that are taken to the extreme with IVT’s, resulting in a ‘neutral’, or non-driving ‘low’ gear limit.] Generally, the usage of the term ‘CVT’ is not used for Infinitely Variable Transmissions because most CVT’s are not IVT’s.

The Continuously Variable Transmission (CVT) should not be confused with the Power Split Transmission (PST), as used in the Toyota Prius and other hybrid vehicles that use two or more inputs with one output. PST’s are not CVT’s, despite some similarities in their function.

CVT’s are not intrinsically automatic, nor do they intrinsically include zero or reverse output. Such features may be adapted to CVT’s in certain specific applications.

Other mechanical transmissions only allow a few different discrete gear ratios to be selected, but the continuously variable transmission essentially has an infinite number of ratios available within a finite range, so it enables the relationship between the speed of a vehicle engine and the driven speed of the wheels to be selected within a continuous range. This can provide better fuel economy than other transmissions by enabling the engine to run at its most efficient speeds within a narrow range.