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. 13, 1986
Filed:
Aug. 12, 1983
Donald E Pezzolo, Cupertino, CA (US);
Intermatic Incorporated, Spring Grove, IL (US);
Abstract
A second photoelectric element or cell (P2) is mounted in series with a first photoelectric element or cell (P1) of the prior art and in parallel with a portion of a voltage divider of which said first element is a part to shunt out a portion of the divider in response to light from a light load turned on by the operation of said first element incident to an increase in impedance thereof due to ambient darkness. Addition of the second photoelectric cell results in hysteresis of the turn-on/turn-off operating points of the first cell to prevent flicker to the light which is present at or near dusk in lights controlled by the prior art circuits. Mechanically, one cell (P1) is mounted on the side of a collar (21) surrounding the neck of a light bulb (13) outside direct light rays from the filament (23) while cell (P2) is mounted on the collar top in the direct path of light rays from the filament.