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:
Apr. 02, 1985
Filed:
Jun. 30, 1982
Peter Heimlicher, Freiburg, CH;
Contrinex S.A., Matran, CH;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
A method of using the temperature coefficient of the copper resistance of an oscillating coil to compensate for the temperature coefficient of the quality factor of the same oscillating coil. To this end, a voltage proportional to the copper resistance of the oscillating coil is generated across the oscillating circuit. The oscillator according to the process comprises an oscillating coil which comprises a high frequency litz wire. In order to access the copper resistance of the coil one of the litz wires is separated from the other wire at a first terminal of the coil and separately connected to a second terminal of this coil. From this second terminal, the coil is seen as a bifilar coil. A constant alternating current source is connected to the second terminal in order to generates across the oscillating circuit a voltage proportional to the copper resistance of the coil. The oscillator is preferably used for proximity switches having relatively large switching distance.