The adjustable eccentric weight can drive to the Central Line of main shaft through motor. Under the unstable state, it produces centrifugal force that makes raw material form vortex in the sieve.

Try "eccentric lifting," in which you focus on lowering the weight during a bench press rather than lifting it.

In eccentric contraction, the muscle produces a force while it's being lengthened. This happens when a person runs downhill, for example, or lowers a weight during a bicep curl.