A novel surface microtexture array generation approach using a fast-tool- feeding mechanism with elliptical cam drive

摘要

This paper presents the development and application of a reciprocating fast-tool-feeding mechanism with elliptical cam drive for rapidly fabricating surface microtexture arrays. Four kinds of different drive-mechanisms involving piston-rod, eccentric-cam, swash-plate-cam, and elliptical cam are devised and analyzed. The elliptical cam is employed as the drive mechanism for the reciprocating feed-tool system. Its symmetrical structural design suppresses systematic vibration, allowing for stable high-acceleration motion, and a speed of response double that of the other tool systems. Finite Element Analysis (FEA) is conducted to predict weaknesses, potential deformation problems, and the resonant frequency of the developed mechanism. Tool trailing stress is derived from the relationship between cutting force normal to the shear plane as well as cutting depth. It is shown that the predicted cutting force fits the required work current. Experimental verifications involving microdimple array generation are implemented to verify the practicability of the feed-tool system. Experimental results demonstrate that a microdimple array of 12 x 34 is promptly finished at a drive-frequency of 10 Hz, workpiece speed of 1200 mm/min, cutting depth of 30 mu m, and processing time of only 40 s. These approaches and conditions generated surface microtexture arrays with highly consistent micro features confirming that the developed reciprocating fast-tool-feeding mechanism is well suited to the high reproducibility of consistently precise machined dense microstructure arrays.