The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 23, 1988
Filed:
Jun. 23, 1986
Giovanni Santoro, Rome, IT;
Ermanno Francolini, Rome, IT;
Other;
Abstract
A soldering tool wherein the soldering tip comprises part of a single loop of iron that forms the energizer means, temperature sensor, heating element and solder melting member. The power oscillator comprises a primary transformer coil that is in series with a primary capacitor to form an LC resonance circuit. The primary transformer coil is inductively linked to the iron loop so that the resistance of the soldering tip forms a load resistance on the LC resonance circuit. The power supply includes first and second power transistors connected to a source of DC current. The base of each power transistor is inductively linked to the primary transformer coil so that the power transistors alternately conduct and supply power to the power oscillator. The frequency and amplitude of oscillations in the power oscillator determines how often and how long the power transistors conduct. Both the frequency and amplitude of the power oscillations decrease with an increase in the load resistance on the power oscillator caused by ohmic heating of the soldering tip. Thus, the temperature of the soldering tip determines how much power the soldering tip receives. The temperature of the soldering tip is regulated by determining at what temperature the load resistance becomes so great that the power oscillator damps out too quickly to draw enough power from the power supply to continue oscillating. A triggering circuit periodically starts the the power supply so that the power oscillator may oscillate again after being damped out. The present invention may respond to an excessive temperature within a single period of oscillation of the power oscillator and may supply additional power to the soldering tip at the frequency of the triggering circuit.