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:
Mar. 23, 1999
Filed:
May. 15, 1997
Isaac L Flory, IV, Blacksburg, VA (US);
Hubbell Incorporated, Orange, CT (US);
Abstract
A reduced cycle ignitor circuit for a high intensity discharge lamp incorporating a thermally timed, cycled operation which provides intermittent starting pulses for the high intensity discharge lamp. The ignitor circuit comprises a capacitor and semiconductor connected in series with a ballast transformer. The ignitor circuit further comprises a series connected resistor and thermostat, having thermally operated, normally closed electrical contacts, through which current is conducted to charge the capacitor. The thermostat is thermally coupled to the resistor. During operation, current flows through the series connected resistor and thermostat and charges the capacitor to a breakover threshold voltage level of the semiconductor. At that point, the semiconductor conducts and the energy stored in the capacitor is discharged through the semiconductor and a winding of the ballast which, through auto-transformer action, generates a high voltage pulse to start the high intensity discharge lamp. The resistor heats the thermostat during the charging cycle which reaches a temperature at which the normally closed thermostat contacts open, which disables the ignitor circuit until the resistor and thermostat cool and the thermostat contacts close.