Abstract: A transmission system of a decelerating mechanism includes a planetary gear unit including a sun gear being adjacent to the first surface and a planetary gear set and a holder including a carrier and several planetary shaft units rotatably disposed on the carrier. The carrier has a first surface and a second surface that face opposite directions. The planetary gear set has several first gears being adjacent to the first surface, respectively fitting around the planetary shaft units, and meshing with the sun gear, several second gears being adjacent to the second surface and being coaxially disposed with the first gears, and an internal gear ring meshing with the second gears. By respectively arranging the first gears and the second gears on two opposite sides of the carrier, mutual interference therebetween while turning could be avoided, and an overall volume of the transmission system could be reduced.

Abstract: A transmission system of a decelerating mechanism includes a planetary gear unit including a sun gear being adjacent to the first surface and a planetary gear set and a holder including a carrier and several planetary shaft units rotatably disposed on the carrier. The carrier has a first surface and a second surface that face opposite directions. The planetary gear set has several first gears being adjacent to the first surface, respectively fitting around the planetary shaft units, and meshing with the sun gear, several second gears being adjacent to the second surface and being coaxially disposed with the first gears, and an internal gear ring meshing with the second gears. By respectively arranging the first gears and the second gears on two opposite sides of the carrier, mutual interference therebetween while turning could be avoided, and an overall volume of the transmission system could be reduced.