Abstract: A control system includes a shift stage determination module and a clutch control module. The shift stage determination module determines a duration of a first power-on downshift when a second power-on downshift is requested, where a power-on downshift is a downshift of a transmission that occurs when an accelerator pedal is depressed. The clutch control module completes the first power-on downshift and selectively starts controlling the second power-on downshift before the first power-on downshift ends.

Abstract: An ECU executes a program including the steps of: starting monitoring the turbine revolution speed and the output shaft revolution speed when a direct shift is started (YES in S100) (S102); performing complete disengagement control on a disengagement element (1) (S106), lowering control pressure of a disengagement element (2) to preliminarily fixed control pressure (S110); starting engagement control on an engagement element (1) when a set time period Is (1) passes (YES in S112) (S114); performing complete disengagement control on the disengagement element (2) when a set time period Is (2) passes (YES in S118) (S120); and starting the engagement control on an engagement element (2) when turbine revolution speed NT is equal to or larger than (the synchronous revolution speed of a gear after a shift—a set value Ns) (YES in. S 122) (S 124).

Abstract: An ECU executes a program including the steps of: starting monitoring the turbine revolution speed and the output shaft revolution speed when a direct shift is started; performing complete disengagement control on a disengagement element; lowering control pressure of a disengagement element to preliminarily fixed control pressure; starting engagement control on an engagement element when a set time period Ts passes; performing complete disengagement control on the disengagement element when a set time period Ts passes; and starting the engagement control on an engagement element when turbine revolution speed NT is equal to or larger than (the synchronous revolution speed of a gear after a shift—a set value Ns).

Abstract: A shift control method and apparatus of an automatic transmission for controlling a shift from one speed, achieved by engagement of a first and a second frictional element, to another speed, achieved by engagement of a third and a fourth frictional element. The method includes detecting a rotation speed of a turbine, detecting a rotation speed of at least one operating member of at least one planetary gear set of the automatic transmission, and controlling the shift according to the rotation speeds of the turbine and the operating member. The control includes overlapping a first shift, from the one speed to an additional speed, with a second shift, from the additional speed to the other speed. The additional speed has a gear ratio that is near a gear ratio of the one speed.

Abstract: An adaptive position kick-down detent mechanism for providing a force feedback to an operator of a vehicle through a drive-by-wire accelerator prior to the transmission performing a kick-down. The kick-down detent mechanism includes a plunger portion, a plunger driving device, and an elastic portion. The plunger portion is slidable within the plunger driving device and is biased by the elastic portion. An electronic control unit communicates a kick-down pedal position to the plunger driving device, which moves the plunger portion to the kick-down pedal position so that the force feedback is provided to the driver before the kick-down even as the kick-down pedal position changes during vehicle operation.

Abstract: When it is decided that it is impossible to shift the automatic transmission directly to the target speed position according to the second shifting-action decision made during a shifting control to shift the automatic transmission to a target speed according to a first shifting-action decision, one of a plurality of candidate intermediate speed positions to which the automatic transmission can be shifted directly is determined as an intermediate speed position. The determined intermediate speed position is established with the largest amount of change of an engine speed NE, and accordingly with the longest time required for completion of the change of the engine speed NE during which a hydraulic pressure of a clutch to be engaged to establish the intermediate speed position can be raised, whereby the clutch engaging pressure can be changed at a rate low enough to reduce a shifting shock of the automatic transmission.

Abstract: A method for effecting a kickdown shift in a transmission of an automotive vehicle controls turbine speed change based on a continuous desired acceleration calculation. The method determines an initial speed of a turbine that transmits torque between an engine and a plurality of gears through a plurality of releasing and engaging elements. A target speed of one of the plurality of gears is determined. A desired time required to increase the turbine speed to the target speed is determined. A desired acceleration of the turbine is calculated according to the initial speed, the target speed, and the desired time. Turbine speed change rate is controlled through controlling the clutch torque of one or more of the releasing and engaging elements based on the desired acceleration.

Abstract: A shift control method for an automatic transmission improves shift feel and acceleration characteristics by determining if 4→3 shifting is required during lift-foot-up 3→4 shift control, and if so, the method controls a number of solenoid valves and friction elements with input from a plurality of sensors that stop the lift-foot-up 3→4 shift when the accelerator pedal is again depressed after being released.

Abstract: A method for controlling an automatic transmission having several gears in which a downshift to a lower gear is triggered when, during an actuation of the acceleration pedal toward an increase of the load input, a shifting characteristic line is exceeded. It is proposed to compare an accelerator pedal gradient signal (DKIG) with a presettable threshold value (DKIG_Limit) and to trigger a downshift already before the shifting characteristic line is exceeded when the actual value of the accelerator pedal gradient signal is great than the threshold value. This significantly reduces the reaction time of the transmission.

Abstract: Disclosed is a shift control method for an automatic transmission that improves shift feel and acceleration characteristics by determining if 4→3 shifting is required during lift-foot-up 3→4 shift control, and if so, the method controls a number of solenoid valves and friction elements with input from a plurality of sensors that stop the lift-foot-up 3→4 shift when the accelerator pedal is again depressed after being released.

Abstract: A method for the control of shifting processes in a vehicle transmission from an initial gear to the next higher target gear includes the steps of continuously determining the vehicle acceleration (a) and the driven rpm (n.sub.2) behind the vehicle transmission. A shifting process is triggered when the acceleration value (a) and the essentially simultaneously recorded driven rpm value (n.sub.2) fall on a shifting point which lies on a shifting characteristic (n.sub.2 (a)) in an acceleration-driven rpm diagram, where the shifting characteristic (n.sub.2 (a)) has a stepped course with at least two break points (a.sub.-- max; a.sub.-- min) and the slope of the shifting characteristic for acceleration values a.sub.-- min<a<a.sub.-- max is always smaller than or equal to the slope of the shifting characteristic for acceleration values a.ltoreq.a.sub.-- min or a.gtoreq.a.sub.-- max. In other words, the following applies:.linevert split.n.sub.2 (a.sub.1).linevert split..ltoreq..linevert split.n.sub.2 (a.sub.

Abstract: Disclosed is a hydraulic control system used in an automatic transmission for a vehicle which includes a plurality of friction elements associated with respective transmission speeds, a hydraulic pressure source, a hydraulic pressure regulating controller for controlling hydraulic pressure from the hydraulic pressure source to constant line pressure, a damper clutch controller for actuating a damper clutch of the torque converter by supplying hydraulic pressure fed from the pressure regulating controller to the torque converter, shift controller for selecting a shift mode by converting hydraulic pressure from the pressure regulating controller into drive pressure corresponding to each speed stage, a hydraulic pressure controller for controlling the drive pressure from the shift controller, and a hydraulic pressure distributor for suitably distributing hydraulic pressure from the hydraulic pressure controller to each friction element for each speed, wherein the hydraulic pressure distributor includes a shift t

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 kickdown control method for automatic transmission wherein a transmission control unit TCU receives signals regarding three variables for a throttle opening rate just prior to an abrupt operation of the accelerator pedal, the vehicle speed and the throttle opening rate changes during the operation of the accelerator pedal; if the throttle opening rate is lower than 20%, the vehicle speed is lower than 20 Km/h and the throttle opening rate change is lower than 30%, the transmission control unit TCU applies to the pressure control solenoid valve a first duty control pattern in which duty rate is constant with respect to time changes from shift start point; and if any one of said variables equal to or higher than the above reference values, the transmission control unit TCU applies to the pressure control solenoid valve a second duty control pattern in which the applied duty rate changes in multi-steps with regard to time change from shift start point.(Fig.

Abstract: A hydraulic control system of an automatic transmission for a vehicle includes a line pressure control part for converting line pressure from a hydraulic pump into constant hydraulic pressure. A torque pressure generating part converts the constant hydraulic pressure fed from the line pressure control part via a manual valve into torque pressure in accordance with the operation of a transmission control unit. A torque pressure switching part switches the supply direction of the torque pressure fed from the torque pressure generating parts in accordance with the operation of the transmission control unit. A shift part primarily feeds the torque pressure fed from the torque pressure switching part to friction members and secondly feeds drive pressure to the friction members after converting the line pressure fed from the line pressure control means into drive pressure.

Abstract: An automatic transmission control device for use in controlling an automatic transmission that includes a plurality of friction engaging devices disposed between the rotational shaft of the engine and the output shaft in order to control gear ratios includes a control device which controls the engaging operation and the disengaging operation of each of the friction engaging devices. The control device changes the time when the engagement side friction engaging device begins to engage based on the gear ratio from which the power-on down shift operation is being made and the gear ratio to which the power-on down shift operation is being made. Thus, in the case of a 4.fwdarw.2 power-on down shift operation the time when the engagement side friction engaging device begins to engage is longer than during a 3.fwdarw.2 power-on down shift operation. In this way, temporary increases in the engine rotational speed are prevented and shift shock is avoided.

Abstract: A shift control apparatus for an automatic transmission includes a first transmission gear unit equipped with a clutch to clutch shift mechanism and a second transmission gear unit which is operatively connected in series with the first transmission gear unit and which is equipped with a clutch to one-way clutch shift mechanism. A clutch controller controls the clutch-to-clutch shift mechanism and the clutch to one-way clutch shift mechanism in such a manner that rotational synchronization of the clutch to one-way clutch shift mechanism is caused to take place earlier than or at the same time as rotational synchronization of the clutch to clutch shift mechanism when gear shifting is effected over the first and second transmission gear units.

Abstract: In a hydraulic control system for automatic transmissions of a vehicle, drive pressure is fed to a first friction member at the first, second and third speeds of a "D" range, drive pressure is fed to a third friction member at a fourth speed, a 2-4/3-4 shift valve for exhausting pressure from the first friction member at third-to-fourth and second-to-fourth speed shifting is connected to an end clutch valve to allow pressure from a first pressure control valve to be fed to the third friction member at the fourth speed, and exhausting of pressure from a releasing conduit of a second friction member and the third friction member via an exhaust conduit connecting the 2-4/3-4 shift valve and a 2-3/4-3 shift valve during fourth-to-second, fourth-to-first and third-to-second speed shifting is delayed by an orifice.

Abstract: A speed change control method for an automatic transmission, which can achieve a smooth skip downshifting even when a driver depresses an accelerator pedal slowly in kickdown. An electronic control unit 6 calculates, at the time when a predetermined time period elapses from the time when a downshifting command from a fourth speed to a third speed is outputted, a difference between the throttle valve opening degree .theta..sub.t1 at that time and the throttle valve opening degree .theta..sub.ts at the time when the downshifting command is outputted, and a change rate (.dwnarw..sub.t1)' of the throttle valve opening degree at the time when the predetermined time period elapses. If the calculated difference is larger than the threshold value .DELTA..theta. and the calculated change rate is higher than the threshold value .DELTA.(.theta.

Abstract: A control system (104)/method for a vehicular automated mechanical transmission is provided, which will compare input signals indicative of input shaft speed (IS) to the product of input signals indicative of output shaft speed multiplied by engaged gear ratio (OS*GR) to develop control parameters indicative of drivetrain torque magnitude and/or phase requiring a driveline torque transducer.