Low-Voltage Percussion Welding

The requirement for new and better connecting techniques in the assembly of telephone apparatus has promoted increased use of welding. A low-voltage percussion welding process has been developed to a stage of reliability and quality which makes its utilization attractive for selected applications. The process is a direct capacitor discharge arc method in which the weld energy is closely controlled by the capacity included in the welding circuit, the voltage to which the capacitors are charged, and the duration of the arc as regulated by the mechanical parameters of the welding device. The low charging voltage is inherently safe to personnel and permits welding both electromechanical and most semiconductor devices without danger of electrical damage. In addition, the short weld time interval of 200-300 microseconds limits heat transfer to such a minute value that the process is particularly attractive for connecting heat sensitive devices. The process currently is applied to weld leads to resistor caps, weld leads to dry reed switches, weld capacitors and resistors to fabricated network circuit boards.