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: When a clutch is disengaged in a D-N shift, a duty ratio of a linear solenoid in a stand-by state at a constant pressure is calculated according to the following equation by using the following values: a reference duty ratio in a stand-by state at a constant pressure; a correction value for an AT oil temperature; a correction value for an engine speed; and respective learning correction values in a N-D shift and a 4-3 coast down shift in which the clutch is engaged. In the equation, K is a coefficient and has a constant value predetermined in the range of 0≦K≦1.

Abstract: A high acceleration time shift control apparatus and method for a vehicle is provided. The high acceleration time shift control apparatus includes a transmission which achieves plural shift speeds whose gear ratios are different from each other; and a high acceleration time upshifting control device which changes a shift speed of the transmission to a higher speed based on a predetermined determination rotational speed such that an input rotational speed of the transmission substantially reaches a target maximum rotational speed when a request for high acceleration is made by a driver.

Abstract: When a current downshift is determined to be a multiple downshift, it is determined whether or not a torque down during a first downshift is in a condition of interfering with learning performed for stabilizing the downshift operation during a second downshift is executed. If the torque down during the first downshift is determined to be in the condition of interfering with the learning, the learning is prohibited.

Abstract: Apparatus for controlling a vehicle drive system including a drive power source, a fluid-operated power transmitting device connected to the drive power source, and an automatic transmission for transmitting a rotary motion of the fluid-operated power transmitting device to vehicle drive wheels such that a speed ratio of the automatic transmission is variable, the apparatus being arranged to increase an output of the drive power source for increasing its speed upon a shift-down action of the automatic transmission so as to increase its speed ratio during a coasting run of the vehicle, and including an output controlling element operable to control the output of the drive power source, and a gradually output increasing device operable upon the shift-down action during the coasting run, for controlling the output controlling element so as to gradually increase the speed of the drive power source at a predetermined rate.

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: Apparatus for controlling a vehicle drive system including an automatic transmission, including a feedback controller operable upon a shift-down action of the transmission effected by concurrent releasing and engaging actions of first and second frictional coupling devices during an operation of a manually operable vehicle accelerating member to drive the vehicle with the drive power soruce, for controlling an engaging force of the first frictional coupling device, and a learning compensator operable upon detection of an abnormality of the shift-down action, for learning compensation of an initial value of the engaging force at which a feedback control of the engaging force is initiated, or an output reducing device for reducing an output of a drive power source when input speed of the transmission has been increased to a value close to a synchronization value, and/or upon racing of the drive power source during the shift-down action.

Abstract: Apparatus for controlling a vehicle automatic transmission having a hydraulically operated frictional coupling device operable to effect a shifting action of the automatic transmission, a switching valve operable according to a shifting command to effect the shifting action, and a pressure regulating valve operable to control a pressure of a working fluid to be supplied to the frictional coupling device through the switching valve to effect the shifting action, the apparatus including (a) a fluid temperature detector operable to detect a temperature of the working fluid, and (b) a delaying device operable to delay a moment of initiation of an operation of the pressure regulating valve to control the pressure of the working fluid to be supplied to the frictional coupling device for effecting the shifting action, such that the moment of initiation is delayed depending upon the detected working fluid temperature, to reduce a shifting shock of the automatic transmission.

Abstract: An apparatus for controlling ignition timing during a shift in a vehicular automatic transmission is provided that is capable of suppressing shift shock in the event that input torque of the automatic transmission is affected by external changes, such as changes in fuel and air pressure and the like, by adjusting immediately to those changes. This control apparatus is provided with an ignition timing controller that controls an ignition timing retard amount; a calculator that calculates a basic retard amount; a detector that detects an engine retard amount; a determinator that determines a retard correction value based on a shift mode of the automatic transmission and the like; and a corrector that corrects the ignition timing retard amount of the controller based on the retard correction value, the basic retard amount, and the engine retard amount.

Abstract: When it has been determined by first determining means that control for a predetermined upshift has been started while an accelerator pedal was not being depressed, and it has been determined by second determining means that a factor that changes an input torque of an automatic transmission has been generated, correction controlling means corrects an engaging pressure of a predetermined hydraulic frictional engagement device by a correction amount in accordance with the factor that changes the input torque. As a result, undershooting of an engine speed, as well as shift shock which results from that undershooting, is able to be preferably suppressed even when a factor that changes the output torque of an engine is generated.

Abstract: An apparatus for controlling a vehicle automatic transmission having a hydraulically operated frictional coupling device operable to effect a shifting action of the automatic transmission, and an accumulator connected to the frictional coupling device, the apparatus including an accumulator-back-pressure learning compensation device operable to effect learning compensation of a back pressure of the accumulator such that an actual value of a rate of change of a rotating speed of a selected rotary element of the automatic transmission, which rotating speed changes as a result of the shifting action, approaches a predetermined target value, and an accumulator-back-pressure control device operable to control the back pressure, on the basis of an output of the accumulator-back-pressure leaning compensation device, whereby a shifting shock of the transmission can be reduced.

Abstract: In a vehicle in which a moderate throttle opening degree control of maintaining a degree of throttle opening that is less than a degree of throttle opening that corresponds to an accelerator operation is performed for a predetermined period following a beginning of the accelerator operation, if it is determined that a clutch-to-clutch downshift judgment has been made, the reduction of the engaging pressure of a disengage-side friction engagement device is restrained until it is determined that the moderate throttle opening degree control has ended. Therefore, even if the turbine torque is returned to a normal value at the end of the moderate throttle opening degree control, insufficient engaging torque is avoided, and the takeover of engaging torque for the clutch-to-clutch downshift is smoothly performed while the turbine torque is stable. Hence, occurrence of a shock related to the end of the moderate throttle opening degree control is suitably prevented.

Abstract: An engine controller for a vehicle having an engine and an automatic transmission, the automatic transmission controlling the engine during a coast-down to a predetermined gear stage, the engine controller having an engine speed detection unit that detects the number of rotations of the engine output shaft an input shaft speed detection unit that detects the number of rotations of the input shaft a power-on detection unit for detecting a power-on state caused by a driver an engine output control unit that controls the output of the engine; and an engine control unit determines an engine speed and an input shaft speed and outputs a signal to the engine output control unit such that a predetermined relationship is maintained between the engine speed and the input shaft speed when the power-on state is detected in the coast-down state.

Abstract: When a clutch is disengaged in a D-N shift, a duty ratio of a linear solenoid in a stand-by state at a constant pressure is calculated according to the following equation by using the following values: a reference duty ratio in a stand-by state at a constant pressure; a correction value for an AT oil temperature; a correction value for an engine speed; and respective learning correction values in a N-D shift and a 4-3 coast down shift in which the clutch is engaged. In the equation, K is a coefficient and has a constant value predetermined in the range of 0≦K≦1.

Abstract: An apparatus for controlling a vehicle automatic transmission having a hydraulically operated frictional coupling device operable to effect a shifting action of the automatic transmission, and an accumulator connected to the frictional coupling device, the apparatus including an accumulator-back-pressure learning compensation device operable to effect learning compensation of a back pressure of the accumulator such that an actual value of a rate of change of a rotating speed of a selected rotary element of the automatic transmission, which rotating speed changes as a result of the shifting action, approaches a predetermined target value, and an accumulator-back-pressure control device operable to control the back pressure, on the basis of an output of the accumulator-back-pressure leaning compensation device, whereby a shifting shock of the transmission can be reduced.

Abstract: Apparatus for controlling a vehicle automatic transmission having a hydraulically operated frictional coupling device operable to effect a shifting action of the automatic transmission, a switching valve operable according to a shifting command to effect the shifting action, and a pressure regulating valve operable to control a pressure of a working fluid to be supplied to the frictional coupling device through the switching valve to effect the shifting action, the apparatus including (a) a fluid temperature detector operable to detect a temperature of the working fluid, and (b) a delaying device operable to delay a moment of initiation of an operation of the pressure regulating valve to control the pressure of the working fluid to be supplied to the frictional coupling device for effecting the shifting action, such that the moment of initiation is delayed depending upon the detected working fluid temperature, to reduce a shifting shock of the automatic transmission.

Abstract: A duty ratio for controlling an engagement force of a friction engagement device on the side of upshift engagement is corrected by an amount corresponding to an intermediate correction control value in the course of the shift. In addition, on a prerequisite condition that learning correction of a constant standby pressure control value at the start of the shift is converged, learning correction is performed for the intermediate correction control value according to a gradient of a turbine speed. Thus, a shift shock is prevented from occurring due to abrupt engagement of the friction engagement device and the like at the completion of the shift.

Abstract: An engine controller for a vehicle having an engine and an automatic transmission for transmitting the rotation of an output shaft of the engine to an input shaft through a fluidic transmission device, changing the speed of rotation by switching the transmission path, and transmitting the rotation whose speed has been changed to driving wheels, the automatic transmission controlling the engine during a coast-down to a predetermined gear stage, the engine controller having an engine speed detection unit that detects the number of rotations of the engine output shaft an input shaft speed detection unit that detects the number of rotations of the input shaft a power-on detection unit for detecting a power-on state caused by a driver an engine output control unit that controls the output of the engine; and an engine control unit determines an engine speed and an input shaft speed and outputs a signal to the engine output control unit such that a predetermined relationship is maintained between the engine speed an

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: Apparatus for controlling a vehicle drive system including an automatic transmission, including a feedback controller operable upon a shift-down action of the transmission effected by concurrent releasing and engaging actions of first and second frictional coupling devices during an operation of a manually operable vehicle accelerating member to drive the vehicle with the drive power soruce, for controlling an engaging force of the first frictional coupling device, and a learning compensator operable upon detection of an abnormality of the shift-down action, for learning compensation of an initial value of the engaging force at which a feedback control of the engaging force is initiated, or an output reducing device for reducing an output of a drive power source when input speed of the transmission has been increased to a value close to a synchronization value, and/or upon racing of the drive power source during the shift-down action.