The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 23, 1992
Filed:
Feb. 28, 1989
Hitachi Seiko, Ltd., Tokyo, JP;
Abstract
A method of and apparatus for effecting a machining operation, e.g. drilling, on a multi-layered printed circuit board utilizing a machining apparatus having a spindle for driving a tool. The spindle is movable in the axial direction of the tool and a pressure foot for pressing the printed circuit board during the machining is mounted on the spindle for relative movement with respect thereto. The method includes the steps of determining the position of the end of a tool with respect to the end of a pressure foot in the state before the pressure foot contacts the printed circuit board, setting the amount of relative movement between the pressure foot and the tool necessary for effecting the desired machining, on the basis of the position of the end of the tool and a predetermined set value of the machining depth; and effecting the machining on the printed circuit board by controlling the feed of the tool in conformity with the amount of relative movement.