Abstract: A shift control apparatus for a vehicle automatic transmission to be provided in a vehicle that includes a hydraulic transmission device having a lockup clutch, an engine, an input shaft connected to the engine through the hydraulic transmission device, and drive wheels. The shift control apparatus includes a shift-down control portion configured, when a shift-down operation is executed to establish a first gear position by releasing a second engagement device, during running of the vehicle in a driven state with a second gear position being established with engagement of the second engagement device, to increase a torque of the engine so as to increase an input rotational speed as a rotational speed of the input shaft through the lockup clutch that is placed in an engaged state, and to release the lockup clutch before the input rotational speed reaches a synchronous speed of the first gear position.

Abstract: The invention relates to a vehicle integrated-control apparatus and method that sets a final control target by coordinating a control target primarily set based on an input of a driver with instruction values from the control systems; and that causes a drive control system to control a drive source and a stepped automatic transmission to achieve the final control target. With this apparatus and method, at least one of the control systems, which provide instruction values to be coordinated with the primarily set control target, is notified of a range of control targets that can be achieved at a current shift speed; a range of control targets that can be achieved by changing the current shift speed to a currently achievable shift speed; and a range of control targets that can be achieved without changing the current shift speed to another shift speed.

Abstract: An ECU executes a program for implementing a method that includes: a step of performing control so that torque capacity Tch of a frictional engagement device that is brought from an engaged state into a disengage state by a downshift operation is gradually reduced to start an inertia phase when a power-on downshift is performed; and a step of stopping the gradual reduction of the torque capacity Tch when the rate of change in an input shaft rotation speed NI of an automatic transmission has reached a desired rate of change ?N(1). Variation in output torque is kept small, and the shock that can occur at the time of a shift is thus reduced.

Abstract: A converterless, multiple-ratio transmission and ratio shift control method wherein smoothness of power-on upshifts and downshifts and power-off upshifts and downshifts is achieved by closed loop control of slip speed and friction element actuating pressure for an oncoming friction element, the data used during the closed loop control including speed sensor information for multiple friction elements during upshift and downshift events.

Abstract: A method for implementing shifts from a source gear to a target gear of an automatic shift transmission includes storing a respective upshift threshold and a respective downshift threshold for each possible sequential gear shift. The respective upshift threshold and the respective downshift threshold are defined in dependence of an accelerator pedal position, such that a limit value that is valid for a respective upshift or downshift is stored as a vehicle speed value in a control device. The vehicle speed that changes while the motor vehicle is driving and a changing accelerator pedal position are measured. Downshifts are simplified for a driver by configuring at least two downshift thresholds to be substantially horizontally extending in a first region of a possible accelerator pedal position and at least partly step-shaped in a second region of the possible accelerator pedal position.

Abstract: A shift control device of a vehicular automatic transmission that establishes a plurality of gear steps of different speed change ratios by selectively engaging a plurality of friction engagement devices ends the shift control by making an engagement end determination regarding an engagement-side friction engagement device if it has been determined continuously for a predetermined time that the input shaft rotation speed of the automatic transmission is in the vicinity of the synchronous rotation speed of the post-shift gear step. The predetermined time is set at a first time if the downshift is a power-on downshift due to a shift judgement in a power-on state, and is set at a second time that is shorter than the first time if the downshift is a power-off?on downshift selected in connection with a change to the power-on state during a power-off shift due to the shift judgment in a power-off state.

Abstract: A shift control apparatus of an automatic transmission of a motor vehicle to which torque is transmitted from an engine via a fluid coupling device is provided. In the automatic transmission including a plurality of hydraulically operated friction elements, a clutch-to-clutch downshift is carried out during coasting of the vehicle by releasing one of the friction elements and engaging another friction element. A controller of the shift control apparatus detects a difference between input and output rotation speeds of the fluid coupling device, and increases an engine speed by a controlled amount based on the difference between the input and output rotation speeds when the clutch-to-clutch downshift is carried out during coasting of the vehicle, so that the vehicle is brought into a minimal driving state in which the engine speed is slightly higher than the output rotation speed of the fluid coupling device.

Abstract: A shift control method for an automatic transmission includes the steps of outputting a predetermined shift control signal while driving in a second speed for controlling shifting into a third speed if signals indicating that shifting from the second speed into the third speed are applied; determining if third speed synchronization is completed; or determining if a tip-in signal has been applied if third speed synchronization is not completed; outputting a throttle compensation duty and determining if signals corresponding to 3-2 kickdown shifting are received if a tip-in signal is applied during third speed synchronization; comparing an oil temperature with a first predetermined value if signals corresponding to 3-2 kickdown shifting are received; comparing a vehicle speed with a second predetermined value if the oil temperature is greater than or equal to the first predetermined value; detecting an On/Off state of a kickdown switch if the vehicle speed is greater than or equal to the second predetermined va

Abstract: A control unit for an automatic transmission provides improved responsiveness to a speed reduction operation by the driver. The control unit includes a speed reduction requirement judging logic which judges whether or not there is a speed reduction requirement. An up-shift is inhibited and prevented when a judgement is made that there is a speed reduction requirement, based at least in part on release of the accelerator. Accordingly, it is possible to prevent a vehicle from being accidentally accelerated by an up-shift operation and to smoothly perform a down-shift to effect an engine brake.

Abstract: In a control method for an automatic transmission, it is first determined if the automatic transmission is in a fourth speed and the vehicle is being driven in a power off state, then a damper clutch operation slip control signal is output when the vehicle is in a power off state. Next, an engine fuel cut-in rpm reduction signal is output to engine control unit when a damper clutch is operated by the damper clutch operation slip control signal. A lower engine fuel cut-in signal is transmitted from the engine control unit according to the output engine fuel cut-in rpm reduction signal. Then, it is determined if engine output is undergoing continuous reduction, and a duty ratio is controlled using a learned value during 4-3 shifting when engine output is being reduced.

Abstract: At downshifting, hydraulic pressure of hydraulic clutch on engaging side (ON clutch pressure) is increased when an input and output speed ratio ("Gratio") has fallen below a predetermined value YGDNS. YGDNS is variably set depending on the vehicle speed and the engine temperature so that it becomes a lower value at a high vehicle speed than at a low vehicle speed, and a higher value at a low engine temperature than at a high temperature. When a downshifting command to a still lower speed stage is issued during downshifting control (when FTBD=1), a downshifting completion processing is performed in the course of the downshifting control (step in S111). Oil pressure in a hydraulic engaging element on the disengaging side QDNOFF and oil pressure in a hydraulic engaging element on the engaging side QDNON are switched to the oil pressures at the time of completion of downshifting, to thereby complete the first step downshifting control at an early time.

Abstract: A control system for downshifting an automatic transmission provides reduced shift shock by controlling pressure fed to a kickdown servo brake. A throttle valve sensor, an input shaft rpm sensor, an output shaft rpm sensor, and a transmission control unit are used. The transmission control unit outputs a control signal for a second-to-first speed shift after reducing hydraulic pressure fed in accordance with a duty pattern when the vehicle is in the state of a second-to-first downshift. Alternatively, the transmission control units outputs a control signal for a second-to-first speed shift after the third-to-second speed shift is completed when the vehicle is in the state of a third-to-first speed shift. In any case, the transmission control units controls first and second transmission control solenoid valves, and a hydraulic pressure control solenoid valve for changing the state of hydraulic pressure fed to every friction member.

Abstract: A hydraulically-actuated multi-step transmission is adapted to prevent the occurrence of engagement shocks of a direct-coupled or lock-up clutch associated with a torque converter. Downshifting is carried out once with the direct-coupled clutch (8) engaged when the vehicle is slowed toward a stop. This is followed by a further downshift with the accelerator released and the direct-coupled clutch disengaged.