GB1164437A - Improvements relating to Soldering - Google Patents

Abstract

1,164,437. Soldering. PLESSEY CO. Ltd. 12 May, 1967 [27 May, 1966], No. 24022/66. Heading B3R. A soldering machine comprises a head, vertically displaceable on a column 3 against a spring, by a lever 4, and a scale 6 for indicating the pressure applied to the workpiece by a V-shaped stainless steel strip soldering element 2. In operation, lever 4 is actuated, until a switch 7 is operated, when a predetermined pressure is applied to the workpiece. A start pulse generating circuit 18 is triggered so as to deliver a start pulse to a monostable circuit 19 having a quasi-stable period of a duration sufficient for soldering to be effected. A pulse is fed to a power gate circuit 10 and current is fed to heat up element 2, through a transformer 8. The output from a thermocouple 11 increases with temperature, and this output is amplified at 12, and fed to a temperature indicator 16. The output is also fed to a D.C. level discriminator 13 which is also supplied with a predetermined temperature signal from a circuit 14. If the temperature from amplifier 12 reaches the predetermined value before the end of the period in circuit 19, a pulse from circuit 15 restores circuit 19, and closes circuit 10 so as to terminate the current supply to element 2. The magnitude of the soldering current can be adjusted by a circuit 20. The machine may be pedal operated, and elements may be in the form of a wire.