Continuously Variable Planetary Transmission

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This Demonstration shows continuously variable planetary transmission in a tilting ball type variator. Such variators have sets of three to 12 rotating and tilting balls between the input and output discs. The tilt of the axes of rotation of the balls is controlled by sliding the central idling cylinder left or right.


As the ball axles tilt, their contact diameters with the discs change, and the speed ratio between input and output varies accordingly.

In this Demonstration, the input (or driving) disc is on the left, the output (or driven) disc is on the right.


Contributed by: Erik Mahieu (April 2013)
Open content licensed under CC BY-NC-SA



A commercial version of the transmission described in this Demonstration is described in [1].


[1] Fallbrook Technologies. "Continuously Variable Planetary Transmissions—A New Technology." (Apr 29, 2013) Summary_ 012213.pdf.

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