Product Description:

The MST291Z-0035-FT-N0RD-S004 is a frameless torque motor section produced by Bosch Rexroth Indramat in the MST Synchronous Torque Motors series. It is intended for direct-drive positioning tables and rotary axes, where it provides continuous torque after installation in a liquid-cooled stator jacket. As a frameless motor section, it is built into the surrounding machine structure rather than used as a finished standalone motor. This arrangement helps reduce transmission components in rotary applications that benefit from direct-drive motion. Because the motor section is supplied without a housing or encoder, the machine builder must add a feedback device and protective enclosure that suit the application.

For thermal management, the stator uses an open cooling jacket that forms part of the machine's coolant circuit. This supports liquid-cooled operation, because a water-glycol mixture passes directly over the windings and removes heat efficiently during continuous torque production. Heat conducted through the aluminum jacket then transfers into the fluid with low thermal resistance. Electrical power is delivered through the factory-terminated INK0653 lead set, and each phase conductor in that cable has a cross-section of 1.0 mm². Because the coolant circuit is part of the surrounding machine, proper flow through the stator jacket is necessary to maintain stable winding temperature during operation.

The electrical interface uses a connection cable arrangement, so no terminal box is fitted to the stator body. Control and temperature sensor lines run alongside the power phases and use 2 × 0.75 mm² conductors, which are suitable for low-level signal currents. There is no built-in encoder, allowing the system designer to select an external feedback device that matches the required accuracy and operating conditions. The motor section also has no housing, so the lamination stack remains exposed until a custom enclosure is added. Routing the power, control, and sensing conductors together can simplify integration where installation space is limited.