NOISE CONTROL FOR HONING MACHINES

THIS PROPOSAL IS DIRECTED TOWARD THE CONTROL TECHNOLOGY RESEARCH AREA TO BE SPONSORED BY THE NATIONAL INSTITUTE OF OCCUPATIONAL SAFETY AND HEALTH. IN PHASE I, A SYSTEMATICAL INVESTIGATION WILL BE PERFORMED OF THE NOISE GENERATED DURING THE PROCESS OF HONING CYLINDERS. THIS NOISE IS OF INTEREST BECAUSE THE EXPOSURE OF THE MACHINE OPERATORS TO THE HIGH FREQUENCY TONES EXCEEDS THE EXPOSURE ALLOWED UNDER THE OSHA NOISE REGULATIONS. FURTHER, THERE ARE NO VIABLE RETROFIT SOLUTIONS TO THIS PROBLEM WITHOUT SEVERE ECONOMIC PENALTIES. PRELIMINARY INVESTIGATIONS PERFORMED BY HOOVER KEITH & BRUCH, INC. HAVE REVEALED THAT THE NOISE RADIATED FROM THE CYLINDER BEING HONED IS NOT DUE TO THE CYLINDER BEING EXCITED AT ITS RESONANT FREQUENCIES. THE EXTREMELY HIGH ENERGY TONAL LEVELS (SQUEALS) ARE EITHER THE RESULT OF A STICK-SLIP PHENOMENON BETWEEN THE HONES AND THE CYLINDER OR THE RESULT OF A RESONANCE OF THE SYSTEM OF THE HONES, THE HEAD HOLDING THE HONES, AND THE HYDRAULIC PRESSURE SYSTEM WHICH MAINTAINS A CONSTANT FORCE ON THE HONES. SEVERAL METHODS OF VIBRATION GENERATION ARE DISCUSSED. AT THE CONCLUSION OF PHASE I, WE WILL UNDERSTANDWHICH OF THESE GENERATION MECHANISMS IS THE CAUSE OF THE SQUEAL. THIS UNDERSTANDING IS CRITICAL IN DEVELOPING A GENERIC NOISE CONTROL SOLUTION FOR HONING AND FOR OTHER MACHINES WHICH PRODUCE SIMILAR NOISE. IN PHASE II, WE WILL EXTEND THIS CONCEPT TO OTHER MACHINERY WITH TOOL SQUEAL, FOREXAMPLE, TURNING AND HOBBING, AND DEVELOP CONCEPTUAL NOISE CONTROL TREATMENTS FOR THE TOOL SQUEAL IN EACH OF THE MACHINES INVESTIGATED. THERE IS TREMENDOUS COMMERCIAL APPLICATION FOR THIS PROJECT WHICH WILL BE REALIZED IN PHASE III. SEVERAL HUNDRED THOUSAND MACHINES EXPOSE EMPLOYEES TO HIGH LEVELS OF TOOL SQUEAL IN VIOLATION OF THE OSHA REGULATIONS. A QUIET TOOL OR TOOL SYSTEM WILL ENABLE MANUFACTURERS TO COMPLY WITH THE REGULATION. IN ADDITION, ORIGINAL EQUIPMENT MANUFACTURERS OF HONING MACHINES AND OTHER MACHINES PRODUCING SQUEALS WILL BE INTERESTED IN ACQUIRING SUCH NOISE CONTROL MEASURES FOR THEIR MACHINES.