| MadSci Network: Engineering |
Reciprocating engines all have a certain speed where the most power is produced. One reason transmissions were created was to increase performance by keeping the engine at or near the optimum speed. Variomatic transmissions are just one style of continuously variable transmission (CVT). The variomatic consists of two basic components: A variable diamter belt pulley in the front, connected to the engine crankshaft, and a clutch/resistance-spring package in the rear (also with a variable diameter). As the engine speed increases, the centrifugal force on the front pulley moves a set of rollers which force the belt to an effectively larger diameter. Since the belt length is fixed, the rear pulley diameter must be reduced which effectively changing the ratio of the system. The advantage of the variomatic is that it will continuously adjust to suit the output of the engine without the operator 'shifting gears'. More details (and the picture) were found at: http://www.iot.dk/~nug gi/scooter/variomat.htm
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