Product Description:

The 1MR480A-B345 rotor is produced by Bosch Rexroth Indramat as part of the 1MB High-Speed Asynchronous Motors series. It is a separable rotating element intended for frameless spindle assemblies where the stator is built directly into the machine housing. By forming the magnetic core of an asynchronous drive, the rotor enables compact, high-speed motion that is essential for automated milling, drilling, and grinding equipment.

This model uses a water-cooled thermal circuit that directs coolant through the surrounding stator jacket, allowing continuous operation without forced air. Its winding and lamination stack correspond to frame size 480, which provides a large active diameter for high power density. The rotor uses an open kit motor design, so it is supplied without an external enclosure and relies on the machine housing for mechanical support and coolant routing. A three-phase cage arrangement supports the slip-based induction typical of asynchronous machines, and the conductive bars align with the 345 mm inner bore that fits over the spindle shaft and bearing system. The rotor uses length code A for the axial stack, and the electrical interfaces maintain the series' IP00 protection class, meaning all live parts remain accessible until the unit is built into the host machine.

Assembly precision is controlled by a step interference fit between the rotor hub and shaft journal, and this press fit helps minimize runout during high-speed operation. To block coolant or cutting fluid from migrating along the step, the manufacturer specifies a single O-ring in the seal groove. Additional leakage control is provided by two set screws that compress a pressure oil seal against the shaft shoulder. When the rotor reaches rated speed, airborne acoustic emission stays below <75 dB(A), helping machine builders meet factory noise limits without extra damping panels.