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:
May. 01, 1990
Filed:
Jan. 10, 1989
Gilbert Petitjean, Igny, FR;
Michel Lebourg, Clamart, FR;
U.S. Philips Corporation, New York, NY (US);
Abstract
A device for marking, for example, the position of a control knob, comprising an arrangement with several terminals each of which corresponds to one of the positions, the application of a DC voltage (+V) at each instant to one and only one of the terminals indicating the presence of the knob in the corresponding position. The device includes a series of operational amplifiers having specified gain, each amplifier having its inverting input connected to one of the terminals and its non-inverting input connected to the terminal corresponding to the next position. Each terminal is connected to a circuit for taking those terminals, which do not correspond to the momentary position of the knob, to a specified voltage. The outputs of the amplifiers are connected to a detection circuit for detecting on one of them any transition whose amplitude exceeds a specified threshold and to control a count-up/count-down device whose output value is incremented or decremented depending on the direction of the transition, this output value constituting an indication of the position of the knob.