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:
Nov. 07, 1989
Filed:
Apr. 29, 1988
Burkhard Tigges, Sundern, DE;
Dierk Brasse, Schalksmuehle, DE;
Werner Turck GmbH & Co., KG, Halver, DE;
Abstract
An inductive proximity switch including an oscillator circuit with a frequency resonant circuit (1) determining the frequency and with an impedance member (7) determining the amplification, this impedance member containing an impedance resonant circuit with a sensor coil (9) that can be influenced by the approach of a metallic trigger. In order to provide that the proximity switch has the same activating range for ferrous and nonferrous trigger metals, the resonant frequency (f.sub.o) of the frequency resonant circuit (1) and the critical impedance value (Z.sub.o) of the impedance member (7) are tuned, according to this invention, to the coordinates (f.sub.o,Z.sub.o) of the point of intersection (P.sub.o) of the impedance/frequency characteristics (II, III), resulting for respectively identical activating range, for an NF trigger and for an FE trigger.