Implementation of an acoustic emission proximity detector for use in generating glass optics

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:535579

Piscotty, M A; Taylor, J S; Blaedel, K L ^[1]

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1. Lawrence Livermore National Lab., CA (United States)

The use acoustic emission (AE) sensing as a method to monitor proximity between a grinding wheel and a brittle material workpiece is being developed at Lawrence Livermore National Laboratory (LLNL) and the Center for Optics Manufacturing (COM) in Rochester, NY. Significantly reducing the amount of expensive {open_quote}air-grinding{close_quote} is one of the primary motivations behind this effort, along with lessening the chances of a crash which could damage the wheel, part and machine tool. AE sensing is well developed and routinely used in the metal working industry for {open_quote}initial contact{close_quote} sensing or tool breakage, for example, and in monitoring diamond turning and grinding processes. However, using AE sensing to switch from a rapid to a final in-feed rate at the detection of initial-contact between the grinding wheel and a brittle material workpiece, such as an optical glass, is often unacceptable during fine grinding (less than 10 {mu}m grit wheels) which produce surfaces with roughness values of 100 {Angstrom} rms or less. In the approach taken here, the authors are sensing the AE prior to contact between the workpiece and the tool. The coolant between the workpiece and the grinding wheel is used as an AE medium to transfer AE signals generated by the relative motions of the coolant, workpiece and wheel. Capitalizing on the repeatability of the AE approach signal, the authors have developed a system to detect the proximity of the grinding wheel relative to the workpiece prior to initial contact.

• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 535579
• Report Number(s): CONF-961111--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
ACOUSTIC MONITORING
GLASS
GRINDING
MANUFACTURING
OPTICAL SYSTEMS