Abstract: A motion transmitting device comprising input and output drive shafts. An eccentric is provided on the input drive shaft and supports a carrier in which an array of pins are disposed. The pins are extended from one end face of the carrier for intermittent engagement with respective "open mouthed" openings provided in a reaction plate fixed to the housing of the device in order to define the gyratory motion of the carrier. The output shaft is provided with a geared member, and where between adjacent teeth on the geared member, a profile of part semi-circular shape is provided which become sequentially and intermittently engaged by all the pins during one complete rotation of the output shaft, and where the number of teeth is one less than the number of pins.