SURFACE MOUNT TECHNOLOGY BREAKAWAY SELF REGULATING TEMPERATURE HEATER

摘要

ABSTRACT:Soldering of surface mount connector terminals tocontact pads on a circuit board is facilitated byconfiguring the terminals and their solder tails as spacedintegrally-formed projections of a selectively actuableheater. Thermal energy developed in the heater isconducted along the projections to the solder tails tomelt fusible conductive material (e.g., solder, at theconnection sites). After cooling, the projections aresevered from the heater. The terminals, which are formedat the distal ends of the projections, are typicallysupplied partially inserted in respective terminal-receiving passages of the connector housing. After thesoldering operation, the terminals are fully inserted intothe passages. The heater is preferably a self-regulatingheater in the form of a copper substrate having a skinlayer of magnetically permeable, high resistance material.An alternating current of constant amplitude and highfrequency is passed through the heater and concentrated inthe skin layer at temperatures below the Curie temperatureof the skin layer material. At higher temperatures, thecurrent is distributed through the lower resistancesubstrate to limit further heating. During the timeinterval required for the surface layer to reach its Curietemperature, the resistive power dissipation createsthermal energy that is conducted to the solder tails.14323 CA