METHOD OF EXPOSING INNER LATER MARKS OF MULTI-LAYER LAMINA HATERIAL

• Main Authors: KITAGAWA SHIRO, FUJIWARA SEINOSUKE, NAKA MASATOSHI, SHOGASE SATORU
• Format: Patent
• Language: English
• Published: 24.06.1986
• Subjects: BORING; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOTDIRECTED TO A PARTICULAR RESULT; DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g.ARRANGEMENTS FOR COPYING OR CONTROLLING; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MACHINE TOOLS; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OFPARTICULAR DETAILS OR COMPONENTS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; MILLING; PERFORMING OPERATIONS; PRINTED CIRCUITS; TRANSPORTING; TURNING

PURPOSE:To prevent generation of faulty products by setting the upper limit of torque on the basis of a mean value of cutting torque required for machining an insulation material laeyr and certainly detecting the start of cutting the second conductive material layer requiring larger cutting torque. CONSTITUTION:Such a physical effect is utilized that the cutting resistance of a conductive material layer is larger than that of an insulation material layer. The upper limit of cutting torque is set by a torque detection unit 12 on the basis of an instantaneous cutting torque value of the insulation material layer 6 or a mean value of the cutting torque in a given period of time. When an end will 10 starts a process of cutting the second conductive material layer 7, the torque increases and a spindle feeding motor 8 is stopped in its operation by means of a control unit 11 so that the end mill may retreat. Accordingly, there shall be no chance of th end mill penetrating through the layer 7 to cut out the inner layer marks.