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:
Aug. 17, 1999
Filed:
Jul. 25, 1996
David A Carrier, Baltimore, MD (US);
Samuel G Woods, Bel Air, MD (US);
David S Strong, Battersea, CA;
Carl W Gifford, Elizebethtown, CA;
Colin M Dyke, Augusta, CA;
Black & Decker Inc., Newark, DE (US);
Abstract
A cordless electric mower having an energy management system that allows a user to operate the cutting blade motor of the mower at a wide range of user selected speeds. The mower is provided with a user adjustable throttle control which, when in the wide-open position allows the cutting blade motor to be rotated at a maximum, predetermined speed. When the throttle is set to some lesser speed, the system automatically implements a speed foldback routine whenever the mower encounters heavy loading which would result in an undesirably high current draw on the battery. When the speed foldback routine is implemented, the system limits the maximum amount of current that can be drawn by the motor until the excessive loading condition has been removed. Once the excessive loading condition has been removed, the speed foldback routine automatically increases the speed of the blade motor back up to almost the originally selected speed. This greatly improves the operating efficiency of the mower and thereby significantly extends the available operating time of the mower on a single charge. The state-of-charge of the battery is also monitored continuously during operation. An LED display provides the user with an indication of the approximate battery charge remaining.