Bevel gear manufacturers now can greatly reduce the time it takes to get fully functional, extremely accurate workholding for their gear testing and development efforts, with Gleason's new Flex-Spand™ (gears) and Flexgrip™ (pinions) workholding solutions. Without sacrificing functionality or typical workholding accuracies of ±0.005 mm (0.0002 inches) total indicator reading, just three standard size modules can meet the requirements of gears and pinions ranging in size from 3.5 inches in diameter up to 8 inches in diameter. For gear development and short-run prototyping or even some production, users now need far fewer Gear Lab workholding systems, on order or in inventory, for a wider range of gears.
Flex-Spand and Flexgrip function much like the other bevel gear workholding in Gleason's array of solutions, where a workpiece is chucked firmly in place when the production machine's draw rod pulls back on an expander in the arbor to actuate the collet that grips the gear. The gear is, at the same time, pulled securely against a backing ring to ensure precision. In the case of Flex-Spand and Flexgrip, however, the expanding collet has been replaced with a set of bolt-on, interchangeable jaws to perform the clamping function, and one backing ring can be used for a wider range of gear diameters. While the application of standard workholding is inherently limited by the exact gear diameter that its collet and backing ring were designed for, the use of interchangeable jaws design means jaws can be easily ground to accommodate a different gear diameter and changed out in an existing arbor much faster and at less expense than ordering a completely new system.
The systems can be applied to Gleason bevel gear cutting and grinding machines for both soft cutting and hard finishing of gears and pinions, as well as Gleason bevel gear lapping and testing machines — and competitive machines with work spindles that have a Gleasontype taper.