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:
Feb. 12, 1985
Filed:
Dec. 16, 1981
Applicant:
Inventor:
Henry R Mallory, Greenwich, CT (US);
Assignee:
Duracell Inc., Bethel, CT (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
F21V / ;
U.S. Cl.
CPC ...
362157 ; 315307 ; 323299 ;
Abstract
A power supply circuit for generating a power pulse train for an incandescent bulb in a flashlight which results in a relatively constant illumination output from the flashlight despite the decline in output voltage from a battery power supply therefor during discharge. The power supply circuit operates to compensate for the lower output voltage from the battery power supply by increasing the duty cycle of the pulse train to provide wider pulse widths therein, and eventually the wider pulse widths merge into a DC power supply near the end of the useful service life of the battery power supply.