Product Description:

The 1MR310B-A094 is a rotor manufactured by Bosch Rexroth Indramat for the 1MB High-Speed Asynchronous Motors series. As the rotating core of a frameless spindle assembly, this component transfers electromagnetic torque into usable mechanical speed for milling spindles, grinding heads, and other automated cutting devices. Integrators combine this rotor with a separate stator and housing so that the motor’s moving mass sits directly on machine-tool bearings, reducing overhang and allowing higher spindle speeds in industrial automation cells.

The rotor’s internal bore measures 94 mm, a diameter that matches the stator’s magnetic air gap while leaving clearance for the machine’s drawbar or coolant tube. Its external geometry aligns with a 310 frame, giving builders a predictable outer diameter and mounting interface across the series. Axial length is identified by the code B, which sets the active stack length and overall magnetic surface area. During acceleration or deceleration, the spindle must overcome rotational inertia; here that value is 0.477 kg·m², enabling rapid speed changes without excessive servo load. The total mass of the rotor is 63.2 kg, a factor that influences bearing preload, vibration behavior, and thermal soak when the spindle is run at sustained high RPM.

A dedicated hydraulic connection allows the rotor to be removed from the stator without prying, which reduces the risk of damage to the laminated core. The journal is ground for assembly with a step interference fit, ensuring concentric seating once the rotor cools to ambient temperature. Because the rotor alone carries no enclosure, its classification remains IP00, and sealing responsibility shifts to the surrounding spindle housing. The unit is identified as a rotor for 1MB frameless spindle motor, confirming compatibility only with matching stator components in that high-speed family.