Belt-Driven Linear Actuators with Ball Bearing Guides - MT Series

Belt-driven linear actuators are mechanical motion systems that convert the rotary motion of an electric motor into straight-line travel using a toothed belt and pulley drive. A timing belt is a flexible belt with evenly spaced teeth that mesh with matching teeth or grooves on the drive pulley, allowing torque to be transferred without the slipping associated with a smooth belt. The belt is attached to a carriage, which moves back and forth along the actuator while supporting the application load. Ball bearing linear guides support and guide this carriage using recirculating balls running between a profiled rail and one or more bearing blocks, providing low-friction motion while resisting forces that could cause the carriage to shift, tilt, or twist.

Belt-driven actuators are particularly well suited to high-speed, long-stroke linear motion. Unlike a screw-driven actuator, where a rotating screw extends through the length of travel and can become increasingly susceptible to vibration or critical-speed limitations as stroke length increases, a timing belt travels continuously around drive and idler pulleys. This allows long travel distances and high linear speeds without requiring a long rotating shaft, while keeping the actuator relatively lightweight.

PBC Linear MT Series linear actuators combine steel-reinforced timing belt drives with recirculating-ball profile rail guides to provide fast, repeatable motion over long distances. The MT family includes MTB, MTE, and MTS configurations, which differ primarily in the number and placement of the linear guides supporting the carriage. In each design, the timing belt provides the driving force while the ball bearing guides maintain carriage alignment and resist radial and moment loads.

MTB linear actuators use one internal profile rail guide with two recirculating-ball runner blocks supporting the carriage. Locating the guide inside the anodized aluminum profile creates a compact design while helping shield the bearing system from the surrounding environment. The MTB configuration is well suited to fast, long-travel applications with relatively balanced loads and moderate pitch, roll, and yaw moments.

MTE linear actuators combine one internal profile rail guide with one external profile rail guide. Adding the external guide creates a wider support arrangement, increasing carriage rigidity and resistance to pitching, rolling, and yawing forces. This configuration provides additional support for heavier or less centrally positioned loads while retaining some of the compact packaging advantages of an internally guided actuator.

MTS linear actuators use two externally mounted profile rail guides, creating the widest guide spacing within the MT family. The greater distance between the ball bearing linear guides provides increased rigidity and stronger resistance to moment loads, making this configuration particularly useful for wide mounting plates, heavy loads, and loads positioned away from the carriage centerline. Because both guides are externally mounted, however, their greater exposure to dust and debris should be considered when selecting an actuator for contaminated environments.

MT Series actuators are built around lightweight, corrosion-resistant anodized aluminum profiles and are available in multiple frame sizes and drive configurations. Features can include steel-reinforced timing belts, adjustable belt tensioning, recirculating-ball linear guides, rigid aluminum carriages, and flexible motor mounting options. Their combination of long travel, high speed, repeatable positioning, and scalable carriage support makes them well suited to gantry systems, packaging machinery, material handling, pick-and-place equipment, machine loading, transfer systems, and other industrial automation applications.

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