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:
May. 15, 1990
Filed:
Mar. 10, 1987
Dr. Ing. H.c.F. Porsche AG, Weissach, DE;
Abstract
In an arrangement for the control of the power transmission of a four-wheel drive vehicle, a main driving axle is driven directly and an auxiliary driving axle is driven via a continuously controllable longitudinal clutch by an internal combustion engine via a clutch-transmission unit. From a desired performance and the speed of the vehicle, a desired traction force of all the wheels is determined. From this desired traction force, and by a distribution factor that is dependent on operating driving parameters, the control quantity is obtained for the control of the longitudinal clutch. In addition, the longitudinal clutch can be controlled alone or in combination with the control quantity by an additional control quantity obtained by squaring of a speed difference at the longitudinal clutch.