reciprocating sifter

  • 1Crank (mechanism) — A crank is an arm attached at right angles to a rotating shaft by which reciprocating motion is imparted to or received from the shaft. It is used to change circular into reciprocating motion, or reciprocating into circular motion. The arm may be …

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  • 2List of Chinese inventions — A bronze Chinese crossbow mechanism with a buttplate (the wooden components have …

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