A transmission mechanism utilizing a source of power which includes a main input shaft that turns upon receipt of power from said source. An auxiliary shaft is turned by the main input shaft through a link that turns the auxiliary shaft at a variable rate relative to the main shaft. A ring gear rotating with the main shaft includes a spur gear in meshing engagement with the same. A gear wheel rotating with the auxiliary shaft connects to the spur gear, via a bearing, for rotation along the ring gear. An output shaft is linked to the spur gear such that the output shaft turns according to the relative turning between the ring gear and the spur gear.