Planetary Arm Bracket And Output Shaft Are One-Piece Constructed To Ensure Maximum Torsional Rigidity. The Gears Adopt The Full-Needle Design,In Order To Broaden Th Contact Area And To Increasing The Structure Rigidity And The Output Torque. The Mild-Steel Gears' Hardness Of Adopting Surface Hardening Technology Is HRC62 ,So That The Abrasion Resistance And Impact Toughness Can Achieve Best. Because Adopting High Technology To Design The Tooth Profiles , The Best Gear Tooth Profiles Are Obtained And The Noise Are Reduced. In Case To Gain Power Transmission,The Maximum Clamping Force And Zero Backlash(Ultra-Precision) Are Obtained By Adopting Double- Locked Method Between The Gearbox Input Side And The Motor Shaft.