Glossary · Motion control and drives
Axis coupling
Also known as: Axis synchronization, Master-slave coupling
German: Achskopplung
In motion control, axis coupling is the functional link between two or more axes in which the motion of a slave axis is derived from the position or velocity of a master axis, for example by a gear ratio or a cam profile.
- Motion control
In one sentence
Axis coupling links axes so a slave axis follows a master axis by a gear ratio or cam profile instead of moving independently.
Example
In a flying saw, the saw carriage is coupled to the conveyor's master axis so it travels at material speed during the cut.
How it applies
- Engineering: Coupling replaces mechanical line shafts, gears and cams. The coupling type, ratio and engagement point are parameters or function block inputs in the control program.
- Commissioning: Engaging and disengaging must be tested at speed: a coupling that engages abruptly can overload mechanics or cause the slave to jump.
- Operation: Communication cycle, Latency and Time synchronization between drives decide how closely the slave follows. Coupling faults usually stop all coupled axes.
- Documentation: Describe which axes are coupled, in which operating modes, and what happens when one axis faults. For maintenance, explain how to decouple axes safely before manual jogging and how to re-synchronize after a repair.
Axis coupling vs. mechanical coupling
A mechanical coupling is a shaft element that physically connects two shafts. Axis coupling is a control function between separately driven axes; nothing mechanical links them, so a control or communication failure can break the synchronization.