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:
Mar. 10, 1976
Ulrich Grisar, Georgsmarienhuette, DT;
Wilhelm Berstermann, Georgsmarienhuette, DT;
Klockner-Werke AG, Duisburg, DT;
Abstract
A spark discharge test apparatus has a holder electrode conductively engageable with a workpiece, a counter electrode adapted to be spaced by a gap from the workpiece while it is in contact with the holder electrode, a power supply including a closable switch and connected across the electrode for passing a unipolar electrical pulse across the gap only when the switch is closed, and a circuit including a terminal connectable to the workpiece and connected so as to close the switch allowing operation of the power supply only on detection of a closed circuit between the terminal and the holder electrode. Thus, a unipolar electrical pulse can only be fired between the counter electrode and the workpiece when the workpiece is in good electrical contact with the holder electrode. This safety circuit comprises a low-voltage relay having one side connected to a low-voltage power supply and another side connected to the terminal. The other side of the low-voltage power supply and the holder electrode are connected to ground.