Product Description:

The 1MS140D-4B-A1 is a stator assembly supplied by Bosch Rexroth Indramat for use in spindle drives that demand high surface speeds and thermally stable operation. It belongs to the 1MB High-Speed Asynchronous Motors series and forms the stationary portion of a frameless motor set, handling the electromagnetic work that drives the rotor. Integrated directly into machine tool spindles or other rotating assemblies, the unit enables compact, torque-dense solutions in industrial automation where space is limited and rapid acceleration is important. Because the stator is installed directly into the surrounding machine structure, it supports compact spindle packages with low external bulk and efficient use of available mounting space.

The stator ships with a 1.5 m connection cable routed through one end of the laminations, which simplifies integration because no additional lead extensions are needed inside the housing. Heat generated by copper losses is removed by liquid cooling, and this coolant path helps keep winding temperatures low during continuous operation. With frame size 140, the outside diameter aligns with standardized bearing cartridges and spindle noses in mid-range machining centers. The mechanical layout uses motor length code D, which gives the active stack a longer length and increases torque output compared with shorter variants of the same diameter. An external aluminum cooling jacket is permanently bonded to the lamination stack, providing structural rigidity and a corrosion-resistant surface for coolant circulation. This arrangement also reduces the need for separate cooling hardware around the active core, which helps preserve a clean spindle envelope.

The electromagnetic makeup follows winding variant 4B, a coil pattern selected to balance voltage constant and slot fill for drives using 600 V DC bus links. The assembly is classified as a stator for a 1MB frameless spindle motor, so it includes only the fixed magnetic portion of the motor system. Rotor parts, bearings, and the rotary encoder are selected separately, and that lets the spindle assembly be matched to the required speed, inertia, and feedback arrangement without changing the stator's electrical characteristics. That separation also allows the rotating components to be selected for the intended duty cycle, whether the application favors maximum speed, lower inertia, or a particular feedback format.