Terms And Data For Servomotors With Gears - YASKAWA Sigma-II Series User Manual

3 Servomotor Specifications and Dimensional Drawings

3.10 Terms and Data for Servomotors With Gears

(1) Terms for Servomotors With Standard Backlash Gears and Low-backlash Gears
Item
Rated Input Motor
Speed (min
Max. Allowable
Input Motor Speed
-1
(min )
Rated Torque
(N m)
Lost Motion
(arc-min)
Torsion Rigidity
(arc-min)
Angular Transmis-
sion Error Accuracy
(arc-min)
* See the following graph for lost motion and torsion rigidity.
(2) Noise Data
The following noise data for a servomotor with a gear is for reference only and may slightly vary with the capac-
ity and gear ratio of the servomotor.
Measurement Conditions:
• Scale A: 50 cm
• Ground Noise: 28 dB
3-44
Terminology for Servomotors with Gears
Measurement Method/Definition
-1
)
The rated output torque of the motor is the gear input torque.
The rated torque is this value multiplied by the inverse of the
gear ratio and efficiency.
Angular difference in the screw with a ±5% rated torque
∗ load. (Maximum value at any four positions during output.)
Highest torsion angle value on one side with a ± rated torque
∗ load
Difference in absolute accuracy for one rotation under load
and no-load conditions during output.
Torsion
rigidity
Initial Noise
Level (dB)
−
−
Torsion
rigidity
Lost
motion
- Torque
±5% Rated torque
Rated torque
Rated torque
100
50
1000
Typical Value
Standard
Backlash
Gears
3000
4000
−
20 max.
27 max.
15 max.
Torsion
rigidity
+ Torque
2000 3000
-1
Input speed (min )
Low-back-
lash Gears
3000
4000
−
3 max.
10 max.
6 max.
4000