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:
Dec. 28, 1999
Filed:
Feb. 03, 1998
Johann Kirchhoffer, Cologne, DE;
Werner Croonen, Bergheim, DE;
Thomas Martin, Puhlheim, DE;
Eric Reichert, Molsheim, DE;
Thomas Wagner, Cologne, DE;
Wolfgang Wickler, Bruhl, DE;
Ford Global Technologies, Inc., Dearborn, MI (US);
Abstract
A control valve system for a multiple ratio automatic transmission having a reaction brake for forward drive and a reaction brake for reverse drive. A first clutch establishes a driving connection between an input gear element and a torque input shaft establishes a forward drive torque flow path when the forward drive brake is engaged. A second clutch connects a different torque input gear element of the transmission to the torque input member when the reverse reaction brake is applied. A pressurized valve circuit with three variable force solenoids, including one variable force solenoid, establishes a controlled circuit pressure, a second variable force solenoid is dedicated for reverse engagement control and a third variable force solenoid is dedicated for forward engagement control, whereby independent reverse engagement pressures and independent forward engagement pressures on the clutches and brakes, are established. A neutral idle characteristic conditions the clutches and the brakes for minimal threshold capacity, which effectively interrupts the torque delivery path through the transmission when the torque input shaft is driven at idle speeds.