Oskar's CVT

Description

Oskar's Continuously Variable Transmission (CVT) is based on one-way bearings. Many CVTs are based on friction. A well-know example is the DAF Variomatic, which uses a push belt between conical pulley plates. This is also used for bicycles by Peyman. Another friction-type of CVT is the Enciolo CVP (Continuously Variable Planetary), which uses a planetary system of swivelling steel balls. Recently, Ratiorez announced their RatioZero CVT that uses one-way bearings (cf ratchets) instead of friction. The use of one-way bearings has the main benefit of being much less tolerances critical than friction-based CVTs. This brings the CVT concept into the realm of makers with 3D-printer.

My CVT uses a piston-like system. A ball chain is just to adjust stroke distance. There are three pistons, with relative phases of 0, 120 and 240 degrees, similar to three-phase electricity. Each piston drives two gears, connected with one-way bearings to the output shaft. One gear is for the forward motion of the piston, and one for the backward motion. So there is a total of six gears, and the system has six phases, one for each gear. The drive shaft is driven with a hexagonal gears. The purpose of the hexagonal gears is to even out the motion of the pistons. This assures that a piston is sliding at a constant speed when it is driving the output axles. This compensation system works exactly for any gearing ratio between the manually-driven input and the output shaft.

Watch the YouTube video.

Read at the iMaterialise Forum.

Read more at the Non-Twisty Puzzles Forum.

Please order a 3D-printed do-it-yourself puzzle kit from iMaterialise at this page (check with Oskar about screws and stickers), or contact Oskar directly if you are interested in obtaining a fully colored, stickered and assembled sample of this puzzle.