Product Description:

The 1MR270C-A090 rotor is produced by Bosch Rexroth Indramat for use in the 1MB High-Speed Asynchronous Motors series. As a frameless spindle component, it works with a matching stator to create a direct-drive motor assembly for machine-tool spindles and similar axes. It provides the rotating mass needed for high-speed machining and accurate positioning in industrial automation equipment. Because it is a frameless element, it is intended to be integrated into the spindle structure rather than used as a standalone housed motor. This arrangement helps keep the drive train compact and reduces compliance between the motor and the spindle interface.

Water cooling follows the IC3W7 circulation pattern, removing heat directly from the rotor surface so the assembly can support the motor's rated output of 30 kW. The electrical rating uses a 380 V line and a nominal current of 96 A, while an inductance of 1.25 mH helps shape inverter response. At this rating, the assembly delivers 190 Nm of torque at 1500 rpm. The rotor uses frame size 270 with length code C, and the winding connections require conductors of at least 35 mm² to limit temperature rise. This cooling method suits enclosed spindle assemblies where airflow is limited, and it supports stable operation during continuous duty.

The stepped interference-fit design keeps the inside rotor diameter at 90 mm and helps maintain concentric alignment with the mating stator. With a mass of 53.3 kg and a moment of inertia of 0.258 kg·m², acceleration and deceleration can be matched to drive limits more accurately. During rapid clearance moves, the rotor can reach speeds up to 12000 rpm. Its open construction carries an IP00 protection class, so it must be installed inside a sealed spindle enclosure. The insulation system uses thermal class 155 F, which supports the temperature range expected in high-speed spindle service.