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:
Jan. 11, 1977
Filed:
Feb. 21, 1975
James J Hinds, LaGrange, IL (US);
Lawrence D Stepenske, Darien, IL (US);
National Can Corporation, Chicago, IL (US);
Abstract
A method and apparatus for detecting cracks or flaws in flanges on the ends of metal container bodies is disclosed herein. The method contemplates generating a magnetic field by passing a primary alternating current having a substantially constant rms value through an inductor means and moving the flange through the magnetic field while monitoring the rms value of the total current passing through the coil and comparing the magnitude thereof with a reference value. A signal is produced when the differential between the values of the total current and the reference exceeds a certain level. The apparatus consists of holding means for receiving and holding a container and means for rotating the holding means about an axis to expose different portions of the flange to a fixed probe positioned adjacent the flange.