Gear Production
Issue link: http://gear.epubxp.com/i/155418
The main steps in the InvoMilling process are outlined in this series of images. Fig. 1 shows initial slot cutting. Fig. 2 shows machining of root and protuberance. Fig. 3 shows turnmilling of the lower gear tooth profle. Fig. 4 shows turn-milling of the upper gear tooth profle to fnish the tooth space. do it, often on the same day. This is a paradigm shift for fexible gear production." InvoMilling involves several machining steps. In the frst step for an outer spur gear, for example, the disk cutter performs like a slot miller to create a groove in the axial direction on the workpiece, forming the tooth space. Next, B-axis rotation of the cutter enables it to machine the geometry of root and protuberance at the bottom of the tooth space. In subsequent steps, the gear wheel rotates in coordination with radial plunging of the cutter to turn-mill the upper and lower gear tooth profles. Chamfers on the gear tooth's OD can also be added. Developers say gear quality of DIN6 or AGMA11 can be achieved using involute milling, with a 2 µm Rz surface fnish on gear fanks. Leaving stock for fnish grinding after heat treating is an option when gears of higher quality and fner surface fnish are required. Of course, on a multitasking machine, other operations can be performed so that the gear, or a workpiece with gear-like features, can be fnished in one setup. This is how InvoMilling can compete as a productive process when gears are not needed in high volumes. In addition, as a multipurpose machine, the multitasking CNC is available for non-gear applications. Figure 1 Figure 2 Figure 3 The Programming Difference Because the tool path determines the gear form, not the shape of the cutter, programming the InvoMilling process deserves attention. Sandvik Coromant worked closely with DMG/Mori Seiki to create a gear-milling module for the MORIAP conversational programming system that Figure 4 September 2013—19