Gear Technology Magazine
www.geartechnology.com/articles/23238

Koepfer’s Versatile MZ 130 Provides Same-Setup Gear Hobbing and Worm Milling

January 10, 2007
Koepfer’s MZ130 hobbing and worm milling CNC machine from Monnier + Zahner was designed with versatility and ease of use in mind. First rolled out at EMO 2005, and in 2006 at IMTS, the seven-axis machine’s multiple capabilities include gear hobbing and worm milling for external spur, helical, worm, face and straight bevel gears, as well as for worms, worm wheels, splines and threads. The MZ130 also features automatic, two-hob gear tooth deburring. Koepfer says a particularly value-added capability of the machine is the availability of no-hassle, CNC-controlled conversion from gear hobbing to worm milling. "The software has conversational programming that allows for fast switching from gear-hobbing mode to worm milling mode," says Troy Kutz, Koepfer America service engineer. "The Model MZ130 takes it one step further through its specialized tooling that allows you to hob and worm mill in the same setup." Other machine capabilities and features include: hob head with CNC-controlled shifting; CNC-controlled, multiple-cut cycles; multiple-cut feed rates, selectable via CNC; CNC-controlled dwell for worm wheels, blind splines, etc.; CNC-controlled electronic differential for hobbing of helical gears; machine-mounted hydraulic unit for workpiece clamping cylinder, etc.; and automatic lubrication system with shot tube for machine ways and re-circulation for the hob head and work spindle. The MZ 130 accommodates large and small batches and includes a universal loader with workpiece magazine. Available options include an eight-axis CNC synchronized tailstock, flexible automation system and automatic skiving. Koepfer says the applications/markets best-suited for the MZ130 include power tools, aerospace, fractional horsepower gear boxes and gear motors, as well automotive and contract manufacturing shops. Maximum workpiece length for the MZ 130 is 250 mm (automatic loading) and 330 mm (manual loading); gear teeth length is 230 mm. The milling cutter diameter for hobbing is 16-40 mm, and 53-100 mm for worm milling. CNC-controlled milling cycles include: straight, helical and crowned gearing; radial, radial-axial, climb and conventional milling, roughing and finishing; worm wheels, straight toothed bevel wheels, worms, front-end toothing; and tailstock (W axis) following the milling cutter synchronously (Z axis).