Product Description:

The 1MR310F-A112 rotor is manufactured by Bosch Rexroth Indramat for the 1MB High-Speed Asynchronous Motors series. It is a rotor for a frameless spindle motor that couples directly to the machine spindle, allowing high rotational velocities required in automated milling, drilling, and grinding centers. By transferring torque without an external housing, the component helps create compact electro-spindles for industrial automation.

The rotor’s mechanical interfaces are made for precise press-fit assembly. A balancing ring can be fastened through an M10 thread so residual vibration can be adjusted after installation. Its axial bore length of 312 mm matches the stator stack length, guaranteeing full magnetic overlap along the active air gap. A 30° chamfer at the leading edge guides the rotor across the stator laminations without gouging them during thermal shrink mounting. The interference zone extends over 315 -0.5 mm, which creates the required grip between the shaft and rotor body. Frame size 310 matches other 1MB components and keeps the same spindle envelope. The minimum spindle length of 408 mm offers clearance for the clamping nuts, and the step interference design keeps radial runout low under speed.

Dimensional tolerances further stabilize dynamic performance. The internal stator interface has an inside diameter of 112 H6, limiting concentricity error between rotating and stationary parts. On the outside, a diameter of 228.7 -0.05 mm provides the shrink-fit interference that resists centrifugal growth at operating speed. The rotor’s magnetic section spans 400 mm, giving adequate pole pitch for the high-frequency inverter signals used in high-speed machining. A groove accepts an O-ring molded from Viton, protecting the spindle bearings from coolant ingress. Motor length code F identifies this rotor as an F-length version in the series and matches it to the corresponding stator length.