Product Description:

The N9M4LR is a low-voltage permanent-magnet DC motor produced by Kollmorgen for the ServoDisc Pancake DC Motors series. Its flat disc armature allows direct mounting in tight axial spaces where conventional cylindrical motors cannot fit. By supplying continuous rotary motion to precision stages, light-duty actuators, and indexing mechanisms, the unit supports high-response positioning tasks common in automated assembly, optical handling, and laboratory equipment.

The motor reaches its nominal operating point at a terminal voltage of 16.0 V, where the shaft turns at 3000 rpm while delivering 44 N-cm of torque. That operating point is supported by a torque constant of 3.60 N-cm/A, meaning each ampere of armature current produces 3.6 N-cm of electromagnetic torque. Copper losses are limited by an armature resistance of 0.180 ohms, while brush and lead contributions add 0.370 ohms at the terminals. During continuous duty, the winding carries 14.00 A. The generated back electromotive force increases by 3.80 V per 1000 rpm, which must be considered when selecting a compatible drive amplifier.

Dynamic events are handled through a peak torque capability of 515 N-cm, supported by a surge current limit of 151 A. The rotor has an inertia of 0.40 kg-cm², allowing the shaft to accelerate quickly without excessive overshoot. The recommended maximum speed is 6000 rpm. A diameter of 111.0 mm and a stack length of 23.9 mm establish the mounting footprint, while the assembly weight of 1.4 kg minimizes the load on lightweight frames. Under rated conditions, the armature produces 140 W of mechanical power, providing a compact drive source for systems that require rapid response within limited installation space.