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:
Jul. 26, 1977
Filed:
May. 08, 1975
Robet L Risberg, Brookfield, WI (US);
Miller Electric Manufacturing Company, Appleton, WI (US);
Abstract
A constant potential single phase A.C. power welding source is connected to a thyristor network and an energy storing inductor to create a square wave welding current that is adjustable in height, and is further adjustable to allow either half-cycle to be wider than the other, the sum of two adjacent half-cycles always equaling 360.degree.. The welding current is forced to reverse rapidly by a substantial voltage to insure conduction when the welding load is an arc to an aluminum work piece, and the aluminum tends to rectify. The heights of the positive and negative half-cycles are simultaneously adjustable in response to manual control and feedback signals. In addition, the ratio of the heights of the positive and negative half-cycles can be other than 1:1 by selectively enabling a conduction path through a different number of turns on the inductor during the negative and positive half-cycles, such enabling being either continuous or on an adaptive feedback basis as a function of arc length as determined by arc voltage. The height difference is effective in a step fashion since the total ampere-turns must remain constant. The thyristor network may also be re-connected for full-wave rectification for D.C. welding.