RKF
The RKF series is a compact servo actuator. It combines a zero backlash Harmonic Drive® gear and an AC servo motor. The RKF Series is designed to operate with a wide range of third party drives as well as Harmonic Drive LLC’s REL Series, and RTL Series.
Key Features:
- Zero backlash
 - Compact and lightweight
 - High power
 - Incremental encoder
 - High positioning and high rotational accuracy
 
Ordering Code
| RKF | - | 20 | A | - | 50 | - | E | 200 | - | SP | 
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 
| 1. | Model | 
 RKF series (Shaft output) 
  | 
| 2. | Size | 
 20, 25, 32 
  | 
| 3. | Version Symbol | 
 A 
  | 
| 4. | Reduction ratio | 
 50,100 
  | 
| 5. | Encoder type | 
 E - Incremental encoder 
  | 
| 6. | Encoder resolution | 
 200 - 2000p/rev 
  | 
| 7. | Special specification | 
 Blank - Standard product  | 
 
Specifications
| Item / Model | RKF-20A | RKF-25A | RKF-32A | ||||
| Gear Ratio | 50 | 100 | 50 | 100 | 50 | 100 | |
| Rated Output | W | 120 | 111 | 180 | 190 | 310 | 310 | 
| Rated Torque | Nm | 19 | 35 | 29 | 59 | 49 | 98 | 
| In lb | 168 | 310 | 257 | 522 | 434 | 867 | |
| Rated Rotational Speed | rpm | 60 | 30 | 60 | 30 | 60 | 30 | 
| Max.Momentary Torque | Nm | 56 | 82 | 98 | 157 | 220 | 330 | 
| In lb | 496 | 726 | 867 | 1389 | 1947 | 2921 | |
| Moment of Inertia | ( GD2/4) kg.m2 | 0.1 | 0.39 | 0.19 | 0.77 | 0.67 | 2.7 | 
| (J) kgfcm2 | 1.0 | 4.0 | 2.0 | 7.9 | 6.9 | 27 | |
| One-way Positioning accuracy | arc.sec | 90 | 90 | 90 | |||
| Encoder resolution of output shaft with quadrature *1  | 
counts/ revolution  | 
400,000 | 800,000 | 400,000 | 800,000 | 400,000 | 800,000 | 
| Mass | kg | 2.9 | 5.0 | 9.5 | |||
| Servo Drive Combinations *2 | AC200 | RTL-230-18, REL-230-18 | |||||
| HA-520-1R-200 | HA-520-3-200 | HA-655-4B-200 | |||||
| HA-655-2B-200 | HA-655-2B-200 | ||||||
*1: Quad encoder resolution is calculated by (Motor shaft resolution) x4x (Reduction ratio)
*2: HA-520 does only position control. HA-655 does speed control and position control.
Product Drawing
RKF-20A, 25A, 32A

Dimensions
Unit: mm
| 
 Model  | 
 A  | 
 B  | 
 C  | 
 D±1  | 
 øE h7  | 
 F  | 
 G  | 
 Mass  | 
| 
 RKF-20A  | 
 180  | 
 20  | 
 64  | 
 96  | 
 100  | 
 60  | 
 108  | 
 2.9  | 
| 
 RKF-25A  | 
 215.5  | 
 22  | 
 69.5  | 
 124  | 
 120  | 
 60  | 
 130  | 
 5.0  | 
| 
 RKF-32A  | 
 241  | 
 25.5  | 
 87.5  | 
 128  | 
 155  | 
 80  | 
 165  | 
 9.5  | 
Please confirm dimensions and specifications with the drawing issued by Harmonic Drive LLC.