Mass-Production Internal Gear Grinding Machine Compatible with Large Internal Gears Up to 350 mm Outer Diameter

Nidec Machine Tool (Wixom, MI) has developed the ZI35A, a new mass-production internal gear grinding machine designed for high-speed, high-precision processing of internal gears up to 350 mm in maximum outer diameter, responding to the growing demand for high precision in large ring gears (internal gears) used in industrial robots, automobiles, and other applications.

Features include:

• Gear outer diameters up to 350 mm and modules from 1 to 4—an increase of 100 mm over the existing model (ZI25A).
• A large, high-rigidity table axis capable of supporting a maximum load mass of 200 kg.
• Stable, high-precision machining even at high speeds, with a maximum table rotational speed of 3,500 min⁻¹ and a maximum grinding wheel spindle speed of 15,000 min⁻¹.
• Supports automated transfer of gears weighing up to 20 kg and is capable of mass production.
• High-efficiency grinding using a barrel-shaped threaded grinding wheel (generating grinding process).Nidec Machine ToolA patented barrel-shaped threaded grinding wheel with a diameter that continuously decreases from the center toward both ends.
• Setting a large axis crossing angle of 20 degrees to 35 degrees between the grinding wheel spindle and workpiece axis increases sliding velocity (grinding speed), achieving highly efficient machining.
• Dressing (re-shaping) can be performed without removing the grinding wheel from the machine.
• An optional dedicated (rotary) dressing device can be mounted.
• Maximum dresser spindle speed: 6,000 min⁻¹.
• An optional touch-probe thermal displacement compensation device that measures fixture outer diameters.
• By measuring the fixture outer diameter before machining and compensating the center distance between the grinding wheel and gear, it suppresses changes in BBD (between balls diameter) during extended continuous operation.

For more information, visit https://www.nidec.com/.