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:
Apr. 15, 1986
Filed:
Mar. 15, 1984
Applicant:
Inventor:
Kunihiko Suzuki, Sagamihara, JP;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B60K / ; F16H / ;
U.S. Cl.
CPC ...
180247 ; 180140 ; 180142 ; 192-358 ; 74740 ; 74856 ;
Abstract
A four-wheel drive system of a part-time type having a two-wheel drive mode and a four-wheel drive mode is provided with an automatic control system for automatically changing the condition of the drive system from the two-wheel drive mode to the four-wheel drive mode when the braking force of the vehicle becomes equal to or higher than a predetermined value. The control system may have means for determining a coefficient of friction between the tire and road surface to change the drive system to the four-wheel drive mode at a low braking force level when the sensed coefficient of friction is low.