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. 17, 2015
Filed:
Aug. 07, 2012
Roger K. Amundson, West Fargo, ND (US);
Jacob C. Kallara, Morrisville, NC (US);
Patrick W. Cross, Cary, NC (US);
Troy W. Harris, Iii, Charlotte, NC (US);
Roger K. Amundson, West Fargo, ND (US);
Jacob C. Kallara, Morrisville, NC (US);
Patrick W. Cross, Cary, NC (US);
Troy W. Harris, III, Charlotte, NC (US);
Deere & Company, Moline, IL (US);
Abstract
An electric lawn tractor roll away prevention system includes a brushless DC electric motor powering a traction drive wheel on the electric lawn tractor. The motor is connected to phase wires and provides a back EMF voltage on the phase wires if the electric lawn tractor rolls and turns the traction drive wheel without electric power from the motor. A three phase inverter rectifies the back EMF voltage, turns on the traction controller if the rectified voltage reaches a pre-specified threshold, and applies a voltage to the phase wires to reduce the speed of the electric lawn tractor by regenerative braking.