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. 16, 2001
Filed:
Oct. 05, 1999
Thomas Alan Porter, Zwingle, IA (US);
Gregory Keith Werner, Durango, IA (US);
Deere & Company, Moline, IL (US);
Abstract
An articulated four wheel drive work vehicle is provided with a front axle having a front differential and a rear axle having a rear differential. Both differentials are provided with hydraulically operated differential locks that are coupled to respective solenoid control valves. The solenoid control valves are coupled to a microprocessor. The microprocessor has a manual mode in which the differential locks are controlled by a foot pedal in the operators cab and an automatic mode in which the microprocessor controls the differential locks in response to speed signals from the axles and the transmission. The microprocessor calculates a predicted axle speed based on the transmission output speed signal received by a transmission speed sensor. The microprocessor then compares this signal to the actual axle speed signals received from axle speed sensors and triggers the respective solenoid valve if the difference is greater than a programmed amount. An articulation angle sensor sends an articulation angle signal to the microprocessor. If the articulation is greater than a programmed amount the solenoid locks are released.