Harmonic driveModel THD-25
THD-25 Hollow-Shaft Harmonic Drive, Size 25
Size 25 hat-type harmonic drive with Ø30 mm hollow bore for cables through the joint. Ratios 30:1 to 160:1, ≤ 20 arcsec backlash.
- Rated torque
- 67N·m
- Peak torque
- 214N·m
- Backlash
- 20 arcsec
- Efficiency
- 78%
Overview
The THD-25 uses a hat-shaped flexspline with an outward flange, which leaves a large hollow bore through the whole unit. Cables, encoders and pneumatic lines pass straight through the joint, keeping the robot arm clean and compact.
Pair it with a hollow frameless torque motor for an integrated joint actuator, or drive it through a belt from an offset servo.
Technical specifications
| Size | 25 |
|---|---|
| Type | Hat type, hollow-shaft unit |
| Ratio range | 30:1 to 160:1 |
| Rated torque at 2000 rpm | 39 N·m |
|---|---|
| Limit for repeated peak torque | 127 N·m |
| Limit for average torque | 72 N·m |
| Limit for momentary torque | 242 N·m |
| Positioning accuracy | 50 arcsec |
| Repeatability | ±10 arcsec |
| Hysteresis loss | 1 arcmin |
| Max input speed | 5,600 rpm |
|---|---|
| Limit for average input speed | 3,500 rpm |
| Hollow bore | 30 mm |
|---|---|
| Weight | 1.9 kg |
| Lubrication | Grease, factory filled |
Values at rated input speed and room temperature. See the datasheet for test conditions and service-life basis.
Ratios, torque and price
| Ratio | Stages | Rated torque | Peak torque | Backlash | Efficiency | Price excl. GST | Availability |
|---|---|---|---|---|---|---|---|
| 30:1 | 1 | 27 N·m | 86 N·m | ≤ 20 arcsec | 78% | ₹56,000 | Made to order |
| 50:1 | 1 | 39 N·m | 125 N·m | ≤ 20 arcsec | 78% | ₹56,800 | 2 in stock |
| 80:1 | 1 | 63 N·m | 202 N·m | ≤ 20 arcsec | 78% | ₹57,700 | Made to order |
| 100:1 | 1 | 67 N·m | 214 N·m | ≤ 20 arcsec | 78% | ₹58,500 | 3 in stock |
| 120:1 | 1 | 67 N·m | 214 N·m | ≤ 20 arcsec | 78% | ₹59,400 | Made to order |
| 160:1 | 1 | 67 N·m | 214 N·m | ≤ 20 arcsec | 78% | ₹60,200 | Made to order |
Drawings and CAD
Mounting and motor fit
- Input
- Hollow wave generator, Ø30 mm through bore
- Output
- Cross-roller bearing output flange with hollow bore
- Fits motors
- Hollow frameless torque motors
400–750 W servos with belt or adapter - Lubrication
- Grease, factory filled
- Protection
- IP54
Need a different flange, housing or coupling?
We machine input flanges for any servo or stepper, custom output flanges, housings and couplings for this model.
Send your motor detailsQuestions about the THD-25
What can pass through the hollow bore?
The Ø30 mm bore takes a typical bundle of motor power, encoder and I/O cables for the next joints, or a pneumatic line for a gripper.
