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 testing a friction component for a transmission that has first and second parts. The first part of the friction component is attached to a drive shaft and the second part is attached to a grounding element. The first part of the friction component is rotated until the drive shaft and the first part of the friction component rotate at a target sliding speed Vtarget. An actuation force is applied to the friction component at a time t0. Operation of the motor drive is continued to maintain the speed of rotation of the drive shaft at Vtarget until a predetermined level of engagement torque Tth is obtained. The motor torque is then reduced to a predetermined level Tm. The sliding speed of the drive shaft is then decreased and the test is terminated when the sliding speed falls to zero.

Abstract: A method for controlling ratio changes in a swap-shift transmission having a first simple planetary gear unit and a second compound planetary gear unit, the two gear units being arranged in series disposition, pressure-operated friction elements for separately braking the reaction member at each of the gear units to establish a change in ratio. The change in ratio consists of a downshift by releasing a reaction friction element for the first gear unit and upshifting the second gear unit by applying a second friction element to anchor a reaction member of the second gear unit in a non-synchronous fashion to achieve a consistent shift quality without precise matching of friction element application and release whereby inertia torque disturbances in the torque output elements of the transmission are avoided.