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. 17, 2003
Filed:
Jun. 27, 2002
Fred C. Porter, Beverly Hills, MI (US);
New Venture Gear, Inc., Troy, MI (US);
Abstract
The hydraulic coupling includes a multi-plate clutch assembly operatively connecting a pair of rotary members, an actuator assembly for actuating the clutch assembly, and a fluid control system operable for controlling actuation of the actuator assembly including a hydraulic pump and a piston mounted in a piston chamber for movement relative to the multi-plate clutch assembly. The fluid control system regulates the fluid pressure supplied to the piston chamber by the hydraulic pump to control the clutch engagement force exerted by the piston on the clutch assembly. The fluid control system includes an electrically-controlled flow control valve operable for regulating the fluid pressure delivered to the piston chamber. Preferably, the flow control valve is a pulse-width modulated PWM) valve having a moveable valve element. The position of the valve element is controlled by an electronic traction control module that monitors and responds to certain vehicle operating conditions, including a sump fluid temperature, a coupling outlet oil temperature, four wheel speeds, and the piston chamber pressure. The electronic traction control module sends a control signal to the PWM control valve for modulating the hydraulic pressure supplied to the piston chamber, which, in turn, controls clutch engagement.