RD-E Series
Strong and precise
The RD-E gear integrates the performance and precision of the RV-E component sets in a ready-to-install gear head. In addition to high torques and reduction ratios, the two-stage cycloidal construction also provides excellent impact resistance and the highest level of precision. The large, integrated angular ball bearings absorb external forces and moments. This makes an additional, customer-provided bearing unnecessary. Construction and assembly times are reduced. The total costs are lowered.
High impact load, rigidity, precision and high torque
The double bearing and the unique RV mechanism comprising rollers and RV gear provide the following advantages:
- Suitable for impact loads up to 5 times the rated torque
- High torsional rigidity
- Low backlash (< 1 arcmin)
- High torque density (high torques with small gear volume)
- High reduction ratio (i up to 1/258)
Bearing for the absorption of external forces
External forces and moments are completely absorbed by two integrated angular ball bearings.
Easy installation
- Completely enclosed assembly (filled with lubricant)
- Simple attachment of the servo motor
Operating Principle
- Fig. 1: First reduction section
- Fig. 2: Crankshaft section
- 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).
- Since they are directly connected, the crankshafts have the same rotational speed as the spur gears (Fig. 1).
- 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).
- When the crankshafts rotate, the two RV gears mounted on the eccentric sections also revolve eccentrically around the input axis (crank movement) (Fig. 2).
- 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.
- 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.
- 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.
- The total reduction ratio is the product of the first reduction ratio multiplied by the second reduction ratio.
