Browse Prior Art Database

Wire Bond Rework Tool

IP.com Disclosure Number: IPCOM000051934D
Original Publication Date: 1981-Apr-01
Included in the Prior Art Database: 2005-Feb-11
Document File: 2 page(s) / 31K

Publishing Venue

IBM

Related People

Coombs, VD: AUTHOR [+2]

Abstract

The tip resistance of a soldering gun tool is selected to be greater than 50% of the total circuit resistance of which it is a part so as to effect a temperature control of the heater zone or region of the tip.

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Wire Bond Rework Tool

The tip resistance of a soldering gun tool is selected to be greater than 50% of the total circuit resistance of which it is a part so as to effect a temperature control of the heater zone or region of the tip.

Hand-held solder gun 10 includes a small transformer 11. The secondary circuit includes a heavy-duty single-turn conductor 12 and serially connected V- shaped bonding tip 13. Conductor 12 is terminated with clamp shaped gold plated ends 12A, 12B which clamp the arms 13A, 13B of tip 13, formed out of flat molybdenum stock. The primary circuit includes multiple-turn primary conductor 14, serially connected trigger switch 15 and adjustable voltage regulator 16.

To maintain the tip-heater temperature proportional to the input voltage Vac, and hence to the resultant emf, the resistance of the tip heater region 17 is selected to be a large proportion of the combined total resistance of the secondary winding circuit elements, to wit, winding 12, connections 12A, 12B, and the tip 13.

Any attempt to cool the heater region 17 results in a decrease in the resistance of tip 13 (and therefore in the resistance of the secondary-winding circuit 12-13) and an immediate increase in the secondary-winding current generated by the emf. Conversely, a tendency of the heater region 17 to overheat results in a significant increase in the resistance of the secondary winding circuit 12-13 and a corresponding reduction in current. These rapid changes in current...