Abstract: A method for actuating a friction clutch, in particular for a motor vehicle drivetrain. The friction clutch is acted on with a clutch pressure generated by a hydraulic actuator arrangement which has an electrically actuable fluid source and which has a hydraulic actuator whose state is characterized by an actuator actual value. The actuator actual value is related to the clutch pressure. The method has the steps: forming a regulation-oriented model of the actuator arrangement, which model has at least one fluid source actuating variable as an input and at least the actuator actual value as a flat output and which model can be inverted; forming an inverse model of the actuator arrangement; and inputting an actuator nominal value into the inverse model and using the model actuating variable which emerges therefrom for actuating the fluid source.
Type:
Grant
Filed:
May 11, 2011
Date of Patent:
February 25, 2014
Assignee:
GETRAG Getriebe- und Zahnradfabrik Hermann Hagenmeyer GmbH & Cie KG
Abstract: An automatic transmission shift control system includes a hydraulically controlled valve mechanism for connecting and disconnecting a supply of hydraulic pressure to frictional coupling elements. Connection and disconnection of the hydraulic pressure supply locks and unlocks the frictional coupling elements in order to automatically shift an automatic transmission into desired gears. A time regulator regulates a duration time for which the valve mechanism is kept actuated and with which a speed at which the frictional coupling element is locked changes. The time regulator is controlled so as to variably regulate the duration time according to conversion efficiency of a torque converter. This conversion efficiency is, for example, determined from a speed conversion ratio and a torque conversion ratio.
Abstract: An automatic transmission mechanism having multiple ratio gearing and clutch and brake elements operated by fluid pressure operated servos for changing speed ratio in the transmission and a controller for actuating and releasing the clutches and brakes in response to operating demands determined by sensed variables such as vehicle speed, engine torque, manual valve position, transmission turbine speed, and engine temperature, and means for achieving improved control of a synchronous downshift event by electronically regulating the exhaust pressure from an off-going friction element of the clutch and brake structure, thus controlling the torque-carrying capacity of that off-going element during the downshift interval.
Type:
Grant
Filed:
May 25, 1993
Date of Patent:
January 24, 1995
Assignee:
Ford Motor Company
Inventors:
Joseph E. El-Khoury, Frank W. Timte, Gerard P. Kuchta, Edmond R. League
Abstract: Imageable products are described which can be made into dry transfer materials and other transfer materials by imaging them in an electrophotographic copier. The imageable products include an adhesive layer having a coating weight of between about 0.5 and 7 grams per square meter, releasably adhered to a substrate. A non-adhesive layer is applied over the adhesive layer, the non-adhesive layer having a thickness of less than about 30 microns and the non-adhesive layer being capable of accepting electrophotographic toner. The non-adhesive layer is incapable of being stripped from the substrate, to which said non-adhesive layer is releasably adhered by said adhesive layer, from a corner of said non-adhesive layer without fracture.