Abstract: A gear ratio shift control and control method controls gear ratio upshifts in a multiple-ratio transmission for an automotive vehicle. Pressure actuated friction elements establish torque flow paths in transmission gearing as they are selectively engaged and released. A net torque reduction at a transmission torque output shaft during an upshift event is reduced by increasing transmission input torque prior to the start of the inertia phase of the upshift event.

Abstract: A gear ratio shift control and control method controls gear ratio upshifts in a multiple-ratio transmission for an automotive vehicle. Pressure actuated friction elements establish torque flow paths in transmission gearing as they are selectively engaged and released. A net torque reduction at a transmission torque output shaft during an upshift event is reduced by increasing transmission input torque prior to the start of the inertia phase of the upshift event.

Abstract: A gear ratio shift control and control method controls gear ratio upshifts in a multiple-ratio transmission for an automotive vehicle. Pressure actuated friction elements establish torque flow paths in transmission gearing as they are selectively engaged and released. A net torque reduction at a transmission torque output shaft during an upshift event is reduced by increasing transmission input torque prior to the start of the inertia phase of the upshift event.

Abstract: A method of controlling engine idle speed in a motor vehicle having an internal combustion engine and multi-ratio transmission when launched from a neutral idle rest condition. At neutral idle, the transmission is controlled such that the input and output members are decoupled. During vehicle launch from neutral idle operation, two different strategies may be employed to control engine idle speed. One preferred method is to determine a feedforward or predicted torque converter load as a function of time. Another preferred method is to determine the feedforward or predicted torque converter load by comparing a maximum engine brake torque and the torque capacity of the forward clutch at any given time. Irrespective of the particular method used, other engine torque loads are added to the feedforward or predicted torque converter load to determine the engine output torque required to control engine idle speed and provide a smooth between transmission operating modes throughout the launch period.

Abstract: A coupling assembly 10 which selectively causes a primary mass or flywheel 20 be engaged or be coupled to a crankshaft 18 as a transmission gear assembly 23 moves from a first gear position to a second gear position and which further selectively causes the primary mass or flywheel 20 to be disengaged or disconnected from the crankshaft 18 as the vehicle is accelerated from an idle state, effective to decrease or substantially eliminate acceleration lag.

Abstract: A method of controlling engine torque in a motor vehicle having an internal combustion engine and multi-ratio transmission when launched from a neutral idle rest condition. At neutral idle, the transmission is controlled such that the input and output members are decoupled. During vehicle launch, two different strategies may be employed to control engine torque. One preferred method is to determine an engine brake torque limit as a function of time. Another preferred method to determine the engine brake torque limit is to estimate the torque capacity of the forward clutch at any given time using a mathematical model and a calibrated offset of turbine torque. Irrespective of the particular method used, the determined engine brake torque limit is compared to the corresponding engine torque amount that is requested by the vehicle operator.

Abstract: A coupling assembly 10 which selectively causes a primary mass or flywheel 20 be engaged or be coupled to a crankshaft 18 as a transmission gear assembly 23 moves from a first gear position to a second gear position and which further selectively causes the primary mass or flywheel 20 to be disengaged or disconnected from the crankshaft 18 as the vehicle is accelerated from an idle state, effective to decrease or substantially eliminate acceleration lag.

Abstract: A control strategy and method for controlling application and release of friction elements in an automatic transmission to effect gear ratio changes as one friction element is release and another friction element is applied during ratio changes. The transmission has an electronic controller and multiple solenoid regulator valves hydraulically coupled directly to pressure-operated friction elements. Powertrain variables are obtained and processed to calculate gear ratio control parameters derived from desired line pressure for a pressure control valve circuit that communicates with the friction elements. The desired gear ratio is determined for each given set of powertrain variables. Upshifts and downshifts are obtained by releasing one friction element in synchronism with an application of the other friction element, whereby a direct friction element to friction element torque transition is achieved with minimal inertia torque disturbances.

Abstract: A rotary clutch assembly for a geared power transmission mechanism comprising a friction disc clutch with driving and driven friction clutch plates, the driving plates being connected to a torque input element of the clutch assembly and the driven plates being connected to a torque output element of the clutch assembly, the clutch assembly providing a torque flow path to multiple-ratio gearing, a pressure actuator comprising first and second annular cylinder members and a movable piston member located in one of the cylinder members and cooperating with each member to define a pressure release chamber and a pressure apply chamber, the second clutch member being held axially fast on a torque input shaft for the transmission, the geometry of the cylinder members and the movable piston being sized to effect a centrifugal balance so that the clutch gain is essentially determined by the clutch commanded pressure to produce a relatively speed-independent net clutch-apply force, regardless of clutch cylinder speed.