MHI Machine Tool launches two new hobbing machines

The Mitsubishi GE15HS, one of two models with enhanced precision and efficiency added to the GE Series. High-speed, high-torque main spindles provide optimal machine structure for high-efficiency processing of mass production gears. (Courtesy: Mitsubishi Heavy Industries Machine Tool Co., Ltd.)

Mitsubishi Heavy Industries Machine Tool Co., Ltd., a part of Mitsubishi Heavy Industries (MHI) Group, recently launched the GE15HS and GE25HS models of hobbing machines. Emphasizing high speed, precision, and efficiency, the new machines produce gears for electric and hybrid cars amid the global trend toward reducing the carbon footprint.

The GE15HS model is for gears with a maximum diameter of 150mm, widely used in automobiles and motorcycles. The high-speed, high-torque direct-drive motor for the main cutting spindle provides a maximum spindle speed of 6,000 rpm — three times faster than previous models. The high efficiency spindle holding the work piece uses a special table that provides high rigidity and high-speed rotation to handle the necessary thrust load for high efficiency machining. Cutting gears with Mitsubishi’s super-hard cutting tools yields a surface roughness of less than Ra0.4; on par with gear grinding. The GE15HS provides process efficiency, eliminating the finishing process of shaving prior to heat treatment, improving productivity, and reducing processing cost.

The GE25HS is for larger gears up to 250mm in diameter, such as automobile differential gears. With its high-efficiency processing, this model uses a high-speed, high-power spindle, eliminating the effects of temperature variations during production. The high rigidity table has the backlash eliminator incorporated as standard equipment. In addition, the motor torque and maximum spindle rotation speed of the main spindle have been increased 1.5 times from previous models, providing a 42 percent reduction in processing time.

Used in combination with MHI Machine Tool’s new materials and coatings for cutting tools, the GE25HS model provides stable mass production with a cutting speed of more than 400m/min.

MHI has delivered and installed more than 2,800 GE Series hobbing machines since the product launch in 2004.

Demand for mass production of high-precision gears is continuing to rise with the shift to electrification of vehicles. With the need for improvements in NVH and fuel efficiency, and the move toward low-cost manufacturing, MHI Machine Tool, with expertise in both gear machine tools and cutting tools, offers a full lineup of gear production machines, including these two new models. By delivering precision cutting tools and processing solutions to achieve high-precision, high-efficiency processing, MHI provides comprehensive support for manufacturing in a wide variety of industries.