Automated system for controlling taper length during the lapping of air

Abstract

An automated system for forming a taper on thin film magnetic heads comprises a lapping fixture positioned in apposition to a rotary lapping plate. A ceramic bar, upon which the magnetic heads are deposited and from which air bearing head sliders are fabricated, is attached to an adjustable transfer tool that is secured to a yoke holder. The holder is fixed securely on the lapping fixture so that the air bearing surface of the magnetic heads face the surface of the lapping plate. During the tapering process, data signals are obtained representative of the length of the taper being formed upon the heads spaced along the bar. The signals are calibrated and processed by a computer which provides command signals for varying the weight or pressure upon the lapping fixture across the fixture during tapering, allowing uniformity of taper to be achieved along with automatic termination of the tapering process upon obtaining the desired taper across the ceramic bar.