Ball Screw Linear Actuators

Ball screw linear actuators combine a ball screw, ball nut, and motor to convert motor rotation into controlled linear motion that moves and positions a load along a straight axis. Recirculating balls between the screw and load-carrying nut reduce friction and provide high mechanical efficiency compared with sliding lead screw nuts. In an external-nut ball screw actuator, the motor rotates the screw while the restrained nut carries the attached load axially along it. Flanged nuts provide mounting points for a carriage or plate, while cylindrical nuts offer a more compact profile. Preload can reduce axial play and increase rigidity and positional accuracy.

PBC Linear ball screw linear actuators include the BS and BE Series, with NEMA 08, 11, 14, 17, and 23 motor frame sizes and ball screws from 6mm to 10mm in diameter. Lead options are 1mm, 2mm, and 2.5mm. Pre-assembled miniature ball screw actuators thus come in six standard diameter-and-lead combinations: 6mm × 1mm, 6mm × 2mm, 8mm × 1mm, 8mm × 2mm, 8mm × 2.5mm, and 10mm × 2mm. The BE Series expands the available configurations with additional motor lengths, leads, nut styles, grades, and performance combinations.

BS Series Grade 10 ball screws provide ±23µm/300mm accuracy, with standard backlash limited to 0.05mm maximum and optional preload for reduced axial play and increased stiffness. Polymer wipers at both ends of the ball nut help exclude debris and retain lubrication around the recirculating balls. Standard and custom journals can be machined on one or both screw ends to interface with bearings, couplings, motor connections, or supports. Fixed and floating end blocks are available to support the screw while accommodating alignment and thermal expansion. Flanged-nut BS configurations provide static axial load capacity up to 2.144kN (482lb).

• Ball screw linear actuators for controlled, load-carrying linear motion
• BS and BE Series external-nut actuator configurations
• NEMA 08, 11, 14, 17, and 23 motor frame sizes
• Screw diameters: 6mm, 8mm, and 10mm
• Lead options: 1mm, 2mm, and 2.5mm
• Cylindrical and flanged ball nut configurations
• BS Series Grade 10 accuracy: ±23µm/300mm
• BS Series standard backlash: 0.05mm maximum; preload optional
• BS Series flanged-nut static axial load capacity up to 2.144kN (482lb)
• Polymer wipers help exclude debris and retain lubrication
• Standard and custom machined journals available on one or both screw ends
• Fixed and floating end blocks available for screw support, alignment, and thermal expansion
• BS Series standard sizes: 6mm × 1mm, 6mm × 2mm, 8mm × 1mm, 8mm × 2mm, 8mm × 2.5mm, and 10mm × 2mm

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