HPS28 Low-Backlash Precision Square Planetary Gearbox (≤10 arcmin) for 28mm (NEMA 11) Motors

This HPS28 precision square planetary gearbox is engineered for 28 mm (NEMA 11) stepper, brushless DC motor, servo motors, or equal motors. Featuring a compact 28 × 28 mm frame and a built-in input shaft coupling, it accommodates motors with a 5 mm shaft diameter and a shaft length of 10 mm. The gearbox delivers high-precision gearing with a backlash as low as ≤10 arcmin and high transmission efficiency, translating the motor's output into smooth, accurate torque multiplication for space-critical motion axes. Its compact square flange and low-backlash design make it well suited to precision positioning tasks in desktop 3D printers, small CNC routers and engravers, medical and laboratory instruments, automated dispensing and pick-and-place systems, optical adjustment stages, and miniature robotic joints where repeatable accuracy and increased torque from a 28mm NEMA 11 platform are essential.

General Specification

• Manufacturer Part Number: HPS28
• Product Type: Precision Planetary Gearbox
• Rated Input Speed: 3,000 RPM
• Max. Input Speed: 6,000 RPM
• Max. Radial Load: 200 N
• Max. Axial Load: 100 N
• Noise: ≤55 dB
• Protection Class: IP54
• Lifespan: 20,000 Hours
• Ambient Temperature: -20° to +150°
• Lubrication Type: Lifetime Lubrication
• Output Shaft Type: D-cut
• Output Shaft Diameter: Φ5 mm
• Output Shaft Length: 20 mm
• Input Shaft Diameter: Φ5 mm
• Input Shaft Length: Max. 10 mm