Brought to you in cooperation with the Musée des Arts et Metiers - Paris.

A gear system is one involved in the transmission of motion. The two toothed wheels  assure a driving force without slippage.  In these four systems,  the driving wheel (at top) turns at a constant speed.

• First case: the "Maltese Cross " system transforms the contiunuous rotation into discontinuous motion: this is a turn counter.
• Other cases: the variable speed of the lower wheel is determined by the wheel's geometry.