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:
Jun. 09, 2009
Filed:
Aug. 03, 2004
Christoph Klees, Köln, DE;
Christoph Klees, Köln, DE;
K.A. Schmersal Holding KG, Wuppertal, DE;
Abstract
The invention relates to an access protection device for a physical area which can be switched on and off in a controlled manner, comprising a fixed part, at least one movable part for closing an access opening in the fixed part and, for each movable part, a tumbler device having a magnetic circuit, which comprises a magnetizable yoke located on the movable part and an electromagnet which can be closed by means of the yoke, it being possible to regulate the locking force of said electromagnet by means of a current regulator, a first and a second desired value being predetermined for the current regulator, and it being possible to periodically carry out a controlled jump from the first to the second desired value, it being possible to measure the time from the beginning of the controlled jump to the time at which the second desired value is reached.