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. 09, 2002
Filed:
Oct. 12, 1999
Karl-Günther Maletschek, Grossostheim, DE;
Jean-Marie Rouillard, La Croix Saint-Ouen, FR;
Poclain Hydraulics Industrie, Verberie Cedex, FR;
Abstract
Apparatus for providing drive assistance in a vehicle having a main transmission that is mechanical. The apparatus comprises a hydraulic motor of the type having radial pistons that is powered by a main pump. The pistons can be retracted into their cylinders in a free-wheel configuration of the motor or they can co-operate with the reaction member of the motor when they are in a working configuration. The apparatus comprises means for implementing successive stages of a sequence for causing the motor to pass from its free-wheel configuration to its working configuration. The sequence comprises an initialization stage in which the case of the motor is filled with fluid at a “service” pressure by means of an auxiliary duct and a service duct, and in which the main feed and exhaust ducts of the motor are placed at a filling pressure that is lower than the service pressure. The sequence then comprises a clutch engagement stage during which the inside space of the case is connected to a fluid return tank and during which the main ducts are isolated from each other.