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:
Jun. 02, 1987
Filed:
Aug. 01, 1986
Kunihiko Suzuki, Sagamihara, JP;
Koji Enomoto, Ebina, JP;
Nissan Motor Co., Ltd., , JP;
Abstract
A four-wheel drive system has a center differential between front and rear wheels, and means for restraining or locking the center differential. The four-wheel drive system is equipped with an automatic control system for automatically locking the center differential when a coefficient of friction between a road surface and a tire of at least one wheel is equal to or lower than a predetermined value. The coefficient of friction is determined by sensing a steering angle, a vehicle speed, a normal load and a steering force, or by sensing an ambient temperature and a humidity. The control system may be arranged to lock the center differential only when the vehicle speed is equal to or lower than a predetermined speed.