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:
Mar. 19, 1984
Hans-Jurgen Fahnrich, Munich, DE;
Ulrich Roll, Munich, DE;
Abstract
To provide for reliable starting of compact-type fluorescent lamps, or ot discharge lamps difficult to start, a voltage divider which is formed only by serially connected capacitors (C1, C2) is connected across the lamp (L), the junction point (5) of the voltage divider being connected to a charging circuit formed by a resistor (R1) and a capacitor (C3). The junction (4) between the charging resistor and capacitor (R1, C3) is connected through a diac (D) to the trigger or gate electrode (3) of a triac (T) connected across the lamp. Preferably, the capacity relationship of each one of the capacitors (C1, C2) of the voltage divider to the trigger capacitor (C3) is between about 1:1 and 1:5, desirably about 1:3. The time constant formed by the charge circuit (R1, C3), preferably, is between about 4 to 6 milliseconds, so that the charge time of the trigger capacitor (C3) is sufficiently long to provide multiple starting pulses to the triac (T) at peak values. A circuit to provide for polarity independence (FIG. 2: G, R2) can be connected between the diac junction (4) and the charge capacitor (C3).