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. 09, 2010
Filed:
Nov. 15, 2006
Yoshinori Sainomoto, Sanda, JP;
Toshiharu Ohashi, Maibara, JP;
Hiroshi Miyazaki, Hikone, JP;
Panasonic Electric Works Co., Ltd., Kadoma-shi, JP;
Abstract
A battery pack for a power tool of self-contained over-charge protection is proposed. The battery pack includes a battery stack composed of a plurality of series connected secondary cells, and a charge terminal connected through a charge current path to the battery stack for flowing a charge current from a charger. The battery pack includes an interrupter inserted in the charge current path, and an over-charge detector which detects a cell voltage across each of the secondary cells and actuates the interrupter to open the charge current path when any one of the cell voltages becomes higher than a predetermined threshold (V). Thus, even if the charger fails to limit the charge current, the battery pack can itself protect the secondary cells from being over-charged.