How to choose a gearbox ratio
The gearbox mounts after the motor flange. Estimate the range from the load torque and the required output speed, then check the ratios on that model's page.
- Higher ratioMore torque, less speed
- Inline planetaryOne mounting
- Right-angle planetaryAnother mounting
- STEPAfter the model is chosen
Ratio changes torque and speed
A higher ratio lowers output speed and increases the available output torque. The final ratio follows the load torque, target speed, mounting space, and gearbox family.
Choose the motor from the stepper or servo range first. The motor path determines the MSP supply, while the gearbox matches output speed and torque.
Three gearbox families do not share one mounting
| Type | Check on its own page | Why the drawings stay apart |
|---|---|---|
| Inline planetary | Flange, backlash, output shaft | The shaft direction differs from a right-angle or worm unit |
| Right-angle planetary | Mounting direction and output shaft | Do not reuse an inline shaft drawing |
| Worm | The mounting on that model's page | The structure differs from both planetary types |
Use the selected model's page for the flange, backlash, and output shaft. The three shaft drawings are not substitutes.
Dimension drawings and 3D models
After selecting the model and ratio, use the plan code to request its dimension drawing, 2D drawing, and 3D model.
Defining the gearbox
Application: the motor flange matches one gearbox family, and the load needs a change in speed or torque.
Configuration: select ratio, backlash, and shaft from the load, speed, and mounting conditions.
Related information
Related pages: Gearboxes