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:
Mar. 29, 1988
Filed:
May. 18, 1987
Hugo S Ferguson, Averill Park, NY (US);
Duffers Scientific, Inc., Troy, NY (US);
Abstract
Apparatus and accompanying methods for use therein for measuring and controlling weld indentation during resistance welding operations are disclosed. During a welding operation, the apparatus measures changes in a distance separating a reference point located on an electrode assembly and a region situated on the surface of the workpiece being welded wherein the region is not substantially indented by the electrode. Specifically, a distance measuring system first establishes the location of the surface relative to the electrode before any welding current is passed through the weld area. The indentation is repeatedly measured by detection of ultrasonic echoes from the surface of the material being welded. Such measurements are taken at frequent intervals during the current flow period during which the weld is being formed in order to determine on a continuous basis the indentation of the electrode into the surface. The welding power may be terminated when the measured indentation reaches the desired value. In order to obtain more precise control of the indentation, the rate at which indentation occurs can be measured and the welding power can be changed on a half cycle by half cycle basis to increase or decrease the indentation rate according to a desired indentation program.