Modern Machine Shop

MAY 2017

Modern Machine Shop is focused on all aspects of metalworking technology - Providing the new product technologies; process solutions; supplier listings; business management; networking; and event information that companies need to be competitive.

Issue link:

Contents of this Issue


Page 30 of 196

28 MMS May 2017 RAPID TRAVERSE Machining Technology in Brief Workholding Basics: When to Use a Diaphragm Chuck Renishaw Inc., call 847-286-9953 or visit BY D E R E K KO R N R on Shibovich, director of engineering for SMW Autoblok, says a diaphragm chuck fo r a tu r n i n g c e nte r f u n c ti o n s s i m i l a r l y to a human's diaphragm that contracts and retracts to draw or "suction" air into our lungs. He says u n l i k e s t a n d a r d c h u c k s t h a t r e l y o n t h e wedge and master jaw linkage for clamping, a diaphragm chuck applies the principle of elastic deformation in expanding, contracting and using resistance to hold workpieces in place. Because diaphragm chucks don't have sliding components, they don't require lubrication and offer a more c o n s i s t e n t g r i p f o r c e r e p e a t i n g t o w i t h i n 10 microns. Mr. Shibovich explains that the accuracy and repeatability of these chucks make them well- suited for a number of applications, including: • Hard turning of gears. Af ter gears are machined and then heat treated, manufacturers typically grind each gear's bore to ensure it is true to the tooth form pitch line. The centering accuracy of the diaphragm chuck, however, enables man- ufacturers to eliminate this grinding process, reducing cost and production time. In fact, the diaphragm chuck was originally developed for Diaphragm chucks were initially developed to eliminate a bore-grinding process that was typically required after a gear is heat treated. u n i t's fo u r th b e a m is d e r i ve d f ro m a pa ir of high-intensity LEDs that are alternatively switched on and off. Each beam is split by a prism within the receiver into two paths with opposite polarization. As the receiver rolls with respect to the incoming beam, the intensities of the t wo split beams var y in opposition. Measuring these intensity changes enables calculating absolute roll at any point along the axis to a resolution of 0.1 arcsecond, Mr. Wilm says. Meanwhile, a target within the receiver tracks the beam's location to reveal the sideways or ver tical motions that indicate horizontal or vertical straightness error. He adds that the system is able to compensate and adjust for ambient lighting changes and alert operators to any poten- tial inaccuracies as it measures. Such peace of mind is critical when it mat- ters—when a ballbar test or even an error reveals something wrong. In that case, manufacturing efficiency may depend on quickly identifying a problem and either fixing it or moving the work to a more precise area of the table, Mr. Wilm c o n c l u d e s. T h e X M 6 0 i s d e s i g n e d to m a ke that easy.

Articles in this issue

Links on this page

Archives of this issue

view archives of Modern Machine Shop - MAY 2017