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, 2014
Filed:
Oct. 10, 2011
Heiko Rosskamp, Adelberg, DE;
Gernot Liebhard, Waiblingen, DE;
René Wichert, Durlangen, DE;
Andreas Stihl AG & Co. KG, Waiblingen, DE;
Abstract
An electric chain saw has an electric drive motor defining a motor-specific characteristic line of the drawn-in current as a function of the rotational speed of the motor. A control unit controls the current flowing through the drive motor below an engaging rotational speed to values below the motor-specific characteristic line. In order to generate an operating point the operator can feel in a working region in a predetermined rotational speed band, a control characteristic line of the electric input power of the electric drive motor as a function of the rotational speed is provided above the engaging rotational speed. The control characteristic line is adapted to reduce the electric input power within the rotational speed band to an approximately even mean power so as to cause the torque of the drive motor to increase within the rotational speed band with falling rotational speed.