Vibrating razor blade machining tool for material removal on low- density foams.

摘要

The Lawrence Livermore National Laboratory (LLNL) has developed an accurate method of machining low-density foams into rectangular blank shapes by using a commercial oscillating razor blade machining tool concept marketed as a Vibratome. Since 1970, Vibratome has been used by medical laboratories to section fresh or fixed animal and plant tissues without freezing or embedding. By employing a vibrating razor blade principle, Vibratome sectioning avoids the alteration of morphology and the destruction of enzyme activities. The patented vibrating blade principle moves the sectioning razor blade in a reciprocating arcuate path as it penetrates the specimen. Sectioning takes place in a liquid bath using an ordinary injector-type razor blade. Although other commercial products may accomplish the same task, the Vibratome concept is currently being used at LLNL to obtain improved foam surface qualities from razor machining by combining state-of-the-art air bearing hardware with precise linear motion and an electrodynamic exciter that generates sinusoidal excitation. Razor cut foam surfaces of less than 25 (mu)m (0.001 in.) flatness are achieved over areas of 8.75 in.(sup 2) (2.5 (times) 3.5 in.). Razor machining of wide or narrow foam surfaces is generally characterized by a continuous curl chip for the full length of the material removed. This continuous chip facilitates flatness and prevents increased surface densities caused by material chip collection often left in the surface cells by conventional machine tools. This report covers the design evolution of razor machining of non-metallic soft materials. Hardware that maintains close dimensional tolerances and concurrently leaves the machined surface free of physical property changes is described. 20 figs. (ERA citation 16:000874)