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:
Jan. 28, 1992
Filed:
Mar. 27, 1991
Bruce A Nielsen, Painesville, OH (US);
William Pickering, University Heights, OH (US);
Caterpillar Industrial Inc., Mentor, OH (US);
Abstract
A motor speed control system for a vehicle is provided. The control system includes an electric motor connected to a power coupling element for delivering electrical energy to the motor in response to a control signal. A sensor produces a current signal in response to the magnitude of the current flowing through the motor. An accelerator pedal produces a command signal in response to a desired vehicle speed. A microprocessor receives the command signal and responsively delivers a pulse width modulated control signal to the power coupling element. The control signal has a duty cycle in a range between a minimum and predefined value. Additionally, the microprocessor receives the current signal and increases the duty cycle of the control signal by a predetermined amount beyond the predefined value in response to the received current signal.