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. 20, 1978
Filed:
Aug. 02, 1976
Jozef Marie van Herten, Venlo, NL;
Bastiaan Bernard Eertink, Grubbenvorst, NL;
Oce-van der Grinten N.V., Venlo, NL;
Abstract
In electrophotographic copying apparatus utilizing a photoconductive belt having markings regularly spaced apart on its back side for control of the copying operations by moving past a detector comprising a light source and a photoelement to generate signal pulses, the detector is made to perform reliably notwithstanding variations of the sensitivity of the photoelement, or of the light emission, by the provision of a circuit for emitting a detector signal proportional to the amount of light sensed by the photoelement together with a signal modifying circuit that maintains an output signal level corresponding to the average value of the detector signal and a control circuit responsive to the output signal level for controlling the intensity of the light source.