RD-C Series Gearbox :: Mechanism

<Fig.1> First Reduction <Fig.2> Crankshaft
  1. Rotation of the servo motor is transmitted through the input gear to the spur gears, and the speed is reduced accordingly with the gear ratio between the input gear and the spur gears <Fig.1>.
  2. Since they are directly connected, the crankshafts have the same rotational speed as the spur gears <Fig.1>.
  3. Two RV gears are mounted around the needle bearings on the eccentric region of the crankshaft. (In order to balance the equal amount of force, two RV gears are mounted) <Fig.2>.
  4. When the crankshafts rotate, the two RV gears mounted on the eccentric sections also revolve eccentrically around the input axis (crank movement) <Fig.2>.
  5. There are pins arrayed in a constant pitch in the grooves inside the case. The number of pins is just one larger than the number of RV teeth.
  6. As the crankshafts revolve one complete rotation, the RV gears revolve eccentrically one pitch of a pin (crank movement), with all the RV teeth in contact with all of the pins.
  7. The rotation is then output to the shaft (output shaft) via the crankshaft so that the crankshaft rotation speed can be reduced in proportion to the number of pins.
  8. The total reduction ratio is the product of the first reduction ratio multiplied by the second reduction ratio.