SIZING AND SELECTION PRECISION COUPLINGS DISC PACK COUPLINGS LP
Symbols
| TKN | Rated torque of the coupling (Nm) |
| TAS | Peak torque of the drive system e.g. max. acceleration torque of drive (Nm) or max. braking torque of load (Nm) |
| JL | Total load inertia (e.g. spindel + slide + workpiece + 1/2 of coupling) (kgm²) |
| JA | Total driving inertia (motor including gear ratio + 1/2 of coupling) (kgm²) |
| CT | Torsional stiffness of the coupling (Nm/rad) |
| fe | Natural frequency of the two mass system (Hz) |
| fer | Excitation frequency of the drive (Hz) |
φ
| Torsional deflection (Grad)
|
According to torque
Couplings are normally sized for the highest torque to be regularly transmitted. The peak torque of the application should not exceed the rated torque of the coupling. The fol- lowing calculation provides an approximation of the mini- mum required coupling size, and allows for the maximum rated speed and misalignment to exist in the application.
According to acceleration torque
A more detailed calculation takes acceleration and the driving and driven moments of inertia into account. A strong inertia ratio diminishes the effect of the load factor in the sizing calculation.