Product Description:

The 1MS376A-QB-A1 stator is manufactured by Bosch Rexroth Indramat for the 1MB High-Speed Asynchronous Motors series. As a frameless spindle motor component, it supplies the electromagnetic field that drives high-speed machine-tool spindles and other automation axes. Because the unit is frameless, it can be built directly into a spindle housing without a separate motor frame. The product integrates an aluminum cooling jacket that surrounds the laminated core, and the stator housing uses the same material to improve heat transfer. A radial cable exit keeps the leads clear of the mechanical envelope, and the factory-installed 1.5 m connection cable is routed through the drive end for direct coupling to the inverter.

At the nominal operating point, this stator draws a phase current of 21.5 A while supporting 6.0 kW of output in the coupled motor assembly. The electrical relationship between frequency and shaft motion corresponds to a rated speed of 240 rpm, which produces a continuous torque of 240 Nm at the output flange. When rapid acceleration is required, the drive can supply up to 70.7 A, giving additional torque headroom without damaging the windings. This operating range supports steady cutting loads as well as short periods of higher demand during speed changes. These current and power values help match inverter capacity, bus capacity, and thermal protection for the complete spindle assembly.

The torque constant of 12.06 Nm/A shows how stator current relates to developed torque during operation. Dynamic response is influenced by the winding inductance of 15.69 mH, while copper losses and temperature rise depend on the winding resistance of 1.898 Ω measured at 20 °C. This combination of electrical values affects how quickly current builds in the windings during control changes. Heat generated under load is removed by liquid cooling, which circulates through dedicated channels to maintain stable insulation temperatures at elevated duty cycles. The compact axial dimension identified by Motor Length Code A leaves additional space for bearing packs and tooling adapters within the same housing.