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. 24, 1990
Filed:
Mar. 16, 1989
Hitachi, Ltd., Tokyo, JP;
Abstract
An apparatus for automatically controlling the welding condition or the welding torch position in arc welding which makes use of a welding power source of constant-voltage or constant-current type. The apparatus has an oscillator for superposing a signal of a predetermined frequency to the arc and a detector for detecting the arc sound pressure level corresponding to the frequency of the superposed signal. This apparatus is capable of accurately detecting the arc length or other factors by a simple method without being substantially affected by the noises produced by the arc. Control of the torch position, as well as welding conditions such as welding current, arc voltage and so on, can be precisely performed by making use of the detection of the arc length.