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:
Dec. 21, 2004
Filed:
Sep. 03, 2003
Daihen Corporation, Osaka, JP;
Abstract
A power supply for arc welding includes switching elements PTR, NTR for switching the polarity of the direct voltage from a power circuit PMC. The element PTR is connected in parallel to a series unit of a switching element TR and a resistor R . Likewise, the element NTR is connected in parallel to a series unit of a switching element R and a resistor R . A necking determination circuit ND determines whether a constriction occurs at the molten bridging portion between the welding wire and the base material. When the constriction occurs during the “electrode positive” mode, the switching element PTR is turned off, while the switching element TR is brought into the conduction state. When the constriction occurs during the “electrode negative” mode, the switching element NTR is turned off, while the switching element TR is brought into the conduction state.