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:
Jul. 15, 2003
Filed:
Jul. 11, 2001
Scott David Dunbar, Cedar Falls, IA (US);
William Guy Alexander, Waterloo, IA (US);
Steven Daniel Wallestad, Cedar Falls, IA (US);
Deere & Company, Moline, IL (US);
Abstract
A vehicle brake system includes a primary hydraulic pump, a secondary variable delivery pump, left and right service brakes and left and right secondary brakes. A service brake valve is connected between the primary pump and the service brakes, and operates the service brakes in response to brake pedal operation. Left and right service brake switches generate signals representing operational status of the service brakes. An electrohydraulic secondary brake valve operates the secondary brakes in response to an electronic control signal. Brake pressure sensors generate brake pressure signals representing the service brake pressure and the secondary brake pressure. An electronic control unit is coupled to the service brake switches, to the pressure sensors and to the secondary brake valve. The control unit generates the control signal as a function of the status of the service brakes and of the brake pressure signals.