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. 02, 2001
Filed:
Mar. 24, 1999
John G. Berger, Landisville, PA (US);
Garth H. Bulgrien, Ephrata, PA (US);
New Holland North America, Inc., New Holland, PA (US);
Abstract
A system for controlling the header speed of a windrower to a set point includes a variable displacement pump producing a variable outflow of hydraulic fluid for driving the header via two hydraulic motors, the system being characterized in that the pump is driven by a pulse width modulated (PWM) signal having a duty cycle that is dependent on the speed and the acceleration of the header. When the header speed falls outside a window or range of speeds centered at the set point, header speed is used to modify the duty cycle of the PWM signal and bring the header speed back within the window. In addition, the duty cycle of the PWM signal is decremented if the acceleration of the header exceeds a threshold and the header includes disk type cutters.