Glossary · Motion control and drives
Torque
Also known as: Moment of force
German: Drehmoment
In mechanics and drive engineering, torque is the rotational effect of a force about an axis, equal to force times lever arm, measured in newton meters (N·m). Motor power equals torque times angular velocity.
- Motion control
In one sentence
Torque is the rotating effect of a force about an axis, force times lever arm, measured in newton meters.
Example
The motor datasheet lists a nominal torque of 5.2 N·m and a peak torque of 15 N·m for short acceleration phases.
How it applies
- Engineering: Load torque, acceleration torque and friction determine motor and gearbox sizing. Gearboxes multiply torque by the ratio (minus losses).
- Commissioning: Torque limits in the drive protect mechanics and can make a stall or collision less severe, but they are standard functions unless validated as safety functions.
- Maintenance: Tightening torques for screws are a separate but common use of the unit in maintenance instructions.
- Documentation: Use "N·m" consistently, with the SI unit and a non-breaking space. Distinguish motor torque, output torque after the gearbox and tightening torque in the text, and state which one a value refers to.
Torque vs. power
Torque is the turning force; power is torque multiplied by speed. A motor can deliver high torque at standstill with no mechanical power output.