Product Description:

The MST291E-0010-FT-N0CN-D303 is a torque motor stator fabricated by Bosch Rexroth Indramat for the MST Synchronous Torque Motors series. Designed for direct-drive rotary tables and similar duties, this frameless stator supplies high continuous torque at low speed so external gear reduction is unnecessary. Its open stator format allows it to be integrated directly into the surrounding machine structure, which helps keep the drive train compact and reduces mechanical backlash in precision rotary axes. That layout is well suited to indexing tables, tilting axes, and other mechanisms that benefit from direct coupling between the motor and the load.

Cooling is provided by liquid cooling, and the jacket channels remove up to 3.70 kW of copper and iron losses so rated thermal limits are maintained. Because the stator is embedded in a machine housing, thermal encapsulation improves heat transfer to the coolant and supports even temperature distribution through the assembly. The hydraulic circuit has only 0.8 bar of pressure drop at the minimum flow rate, which allows the use of compact pumps. Electrical loading includes a rated current of 20.0 A for continuous operation, while the winding resistance is 4.4 Ω at 20 °C and the inductance is 56.0 mH. With a torque constant of 28.75 Nm/A, current is converted efficiently into torque, and the back EMF constant of 1.920 V min⁻¹ indicates the generated voltage in relation to speed.

Mechanical output reaches a maximum torque of 1250 Nm for startup or indexing moves, while the continuous rating is 570 Nm at the stated coolant flow. When the rotor is locked, the winding can deliver 21.8 A to hold a load and produce standstill torque without overheating. The laminated core and windings weigh 25.0 kg, which keeps added axis mass moderate while still providing high torque density. Low winding resistance also helps the stator respond well during rapid torque changes in servo applications. This arrangement supports smooth motion at low speed, where direct-drive systems are often used to improve positioning accuracy and reduce wear from intermediate transmission components.