International Business Machines Corporation

James M Ergler

James D Herard

Norman A Card

Der-jin Woan

Paul R Kasperek

Richard S McKinley

Harold Kohn

Michael Smetana

A method and apparatus is described for reworking a printed circuit board having plugged vias and plated through holes. The printed circuit board, supported by a movable local support, is heated from only the bottom side by a heating device near the area on the PCB that contains the plated through hole or holes to be reworked. The heating device is removed when the solder in the plugged PTH is completely melted. At that time, blast air is turned on to remove and blow off the excess solder in the PTH. The compressed air is more effective in displacing the molten solder than is vacuuming, and has less chance of damaging the PCB than do conventional reworking methods, due to the non-contact nature of the invention.

Process for reworking circuit boards

Machine and process for reworking circuit boards

Stripping and cutting apparatus in which a pair of disc cutters are affixed on a common rotatable shaft that is pivotably mounted to a rotating head. An object having an inner core member and an outer concentric member, which in the preferred embodiment is insulated conductive tubing, is advanced through a central opening in the head. The speed of the head is controlled so that at one speed the shaft is centripetally pivoted to an inner radial position that causes the closest of the cutters to block the leading end of the object, and so that at another faster speed the shaft is centrifugally pivoted to an outer radial position which removes the particular cutter from the blocking relationship with the leading end of the object thereby allowing the object to be advanced past the remote cutter for a predetermined distance, and so that at another speed, which is less than the last mentioned speed, the shaft is centripetally pivoted inward to provide concurrent cutting of the object by the two disc cutters. One of the cutters cuts a piece from the object and another cuts a portion of the outer member of the object, which portion is stripped from the cut piece by and between the cutters. The aforementioned closest cutter acts as reference plane for cutting the object in respective uniform lengths for the pieces and/or portions.

Centripetal cutter and stripper apparatus

Growing community of inventors

Friendsville, PA, United States of America

James M Ergler