Mitsubishi Heavy Industries, Ltd. (MHI), unveiled two newly developed “dry-cut” type gear cutting machines at the 24th Japan International Machine Tool Fair, which took place at Tokyo Big Sight recently. The SE15A, which can process workpieces up to 150 millimeters in outside diameter, will be added to the company’s SE series of dry-cut gear shaping machines. The new GE25A, a gear hobbing machine, will become available with a newly added chamfering device.
The SE15A enables high-speed processing of small-size workpieces and will be available in two types with different peripheral device arrangements—a stand-alone type, and a production line configuration type—to meet the customer’s specific production environment. It is a fully dry-cut type unit that does not require cutting oil to reduce wear of the cutting tool or cleaning of the tool and workpiece during the cutting process, produces no oil mist or waste oil, and as a result contributes to a clean working environment while also addressing environmental demands. The machine also eliminates electricity normally needed for cutting oil-related devices such as the oil circulation pump and cutting oil cooler, thereby enabling a 20-percent saving in energy compared with the SD15CNC, the existing “wet-cut” machine for small-size workpiece machining.
Featuring counterbalancing shafts optimally arranged within the gear train of the machine’s drive system, the SE15A greatly reduces vibration and noise and enables stable machining at a maximum high speed of 2,000 spindle strokes per minute, about 50-percent faster than the current model. Together with a new machine design that requires roughly 18-percent less installation space than the SD15CNC, the SE15A facilitates easy configuration of production lines through modularized peripheral equipment and a conveyor system. Easy and simple operation software for setting the machining conditions and graphic display of the machine’s operating status further enhance this model’s operability and ease of maintenance.
The new GE25A, based on the current GE25A system, is now equipped with a gear-tooth chamfering device. In customer’s preference, the new machine is also available with a new hob introduced earlier this month, which uses Dry Cut III thin-film coating technology. Through these refinements the new GE25A achieves a high-speed cycle time of 40 seconds for a final reduction gear of passenger cars together with highly precise hobbing capability. The elimination of chamfering after the hobbing machine, which has been required for the previous GE25A model, enables more compact gear cutting lines.
The GE25A is capable of dry-cut machining of workpieces up to 250 millimeters in outside diameter, such as final reduction gears of automobiles, at a high speed of 250 meters per minute with high accuracy conforming to Japanese Industrial Standards (JIS) N8 grade standards. This is achieved by increasing the number of index points of the ring loader for automatic workpiece shifting to four, doubled from the previous model. The four-position ring loader moves the hobbed workpiece to the next index point of the chamfering station. By integrating the chamfering and hobbing processes, productivity is enhanced and a more-compact gear cutting line becomes possible. For improvement of the working environment, workpiece machining is conducted within a fully enclosed unit to prevent machining chips from scattering. As with the SE15A, the new GE25A is equipped with easy, simple operation software.
Along with further expansion of its dry-cut gearing cutting machine portfolio, MHI will introduce additional Dry Cut III tools, which have greatly enhanced wear resistance compared with existing tools, to provide customers with gear cutting systems incorporating both dry-cut machines and tools. The company will vigorously conduct marketing activities for this portfolio in a quest to respond flexibly to all customer needs and production environments.
To learn more go to [www.mhi.co.jp/en]. The local contact is Thomas Kelly—senior vice president, Mitsubishi Heavy Industries America, Machine Tool Division—who can be reached at (248) 668-4143. Also go to [www.mitsubishigearcenter.com].
