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:
Feb. 16, 1993
Filed:
Oct. 30, 1991
Gary W Cuba, Hopkins, SC (US);
Robert D Isaacson, Columbia, SC (US);
David V Lambert, St. Matthews, SC (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
An apparatus for setting an arc gap between a weld electrode and a workpiece includes a control arrangement and a direct current stepping motor operated in a forward mode by the control arrangement to move the weld electrode toward and away from the workpiece to respectively advance and retract the electrode into and from physical contact with the workpiece. The apparatus also includes an electrical circuit connected to the weld electrode and the workpiece for defining an electrical path to supply electrical energy sufficient to generate a welding arc between the electrode and workpiece, and an electrical continuity sensor connected to the electrical path and being operable for sensing the opening and closing of electrical continuity of the electrical path and for generating a trigger signal to the control arrangement in response to sensing the closing of continuity of the electrical path by the electrode making physical contact with the workpiece. The control arrangement in response to receipt of the trigger signal from the continuity sensor causes the electric motor to operate in a reverse mode to retract the electrode from physical contact with the workpiece to a welding position located a predetermined distance from the workpiece. A vacuum relay is operable to isolate the continuity sensor from the electrical path in response to receipt of an output signal generated by the control arrangement when the electrode reaches the welding position.