Captive Linear Stepper Motor

Captive linear stepper actuators integrate the lead nut into the motor assembly and use an internal anti-rotation mechanism to convert motor rotation into linear travel. In a typical design, the screw is coupled to a spline shaft and guided by a spline bushing. This arrangement limits screw rotation while allowing the shaft to move axially, so the actuator extends and retracts as the motor turns clockwise and counterclockwise.

Because the anti-rotation function is built into the actuator, the unit can provide push/pull linear motion to an attached load without requiring an external anti-rotation fixture. Actual thrust capability and positioning results depend on the motor size, screw lead, drive settings, and the application load.

Captive linear stepper actuators are available in common NEMA frame sizes including 8, 11, 14, 17, and 23. Multiple screw leads and stroke lengths are offered depending on the model series; dimensional drawings and rated performance data should be used to confirm fit and output requirements.

Typical applications include automated HVAC damper positioning and other mechanisms that require repeatable linear adjustment. Noise, contamination tolerance, and operation depend on speed, microstepping configuration, lubrication, and environmental sealing specified for the selected model.

Custom machining or material options may be available for specific projects, subject to engineering review and manufacturing feasibility.