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:
Dec. 01, 2009
Filed:
Jan. 10, 2006
Thomas Kuehn, Manheim, DE;
Thomas Kuehn, Manheim, DE;
Pepperl + Fuchs GmbH, Mannheim, DE;
Abstract
The invention relates to a proximity switch, particularly an inductive proximity switch, with an oscillator having an at least partly self-compensated feedback network influenceable by a target to be detected, as well as an oscillator amplifier. The invention is characterized in that the oscillator amplifier has an amplifier component and a controllable network for controlling the gain of the oscillator amplifier, that the controllable network has a passive coupling network, particularly negative feedback network, and a controllable transconductance amplifier for controlling a transfer function of the controllable network, that a temperature sensor for determining the temperature of at least the oscillator amplifier is provided and a signal derived from an output signal of the temperature sensor is used as a control signal for the transconductance amplifier, and that the oscillator amplifier on the basis of the temperature determined by the temperature sensor by means of the transconductance amplifier is controllable in such a way that temperature-caused variations of the oscillator characteristics are at least partly compensatable.