Abstract: A hydraulic control system includes a linear solenoid valve, an ON-OFF solenoid valve and a hydraulically-operated frictional engagement device. A first hydraulic pressure is regulated by the linear solenoid valve within a predetermined pressure-regulation control range, and is supplied to the frictional engagement device. In a state in which the frictional engagement device is placed in a predetermined engaged state based on the first hydraulic pressure, a second hydraulic pressure, which is higher than the pressure-regulation control range, is supplied from the ON-OFF solenoid valve to the frictional engagement device, such that the frictional engagement device is placed in a fully engaged state with a high engaging torque based on the second hydraulic pressure.

Abstract: A control device controls a lockup clutch interposed between an engine and an automatic transmission mechanism of a vehicle. The control device includes a control part supplying hydraulic pressure to the lockup clutch and controlling differential pressure of the lockup clutch. The control part supplies the hydraulic pressure to the lockup clutch so that the differential pressure is lower than a reference differential pressure in a disengaged state of the lockup clutch. In a case of shifting the lockup clutch from the disengaged state to an engaged state, the control part supplies the hydraulic pressure to the lockup clutch so that the differential pressure increases as a filling ratio of an oil passage of the lockup clutch decreases. The reference differential pressure is a lower limit of the differential pressure that increases a slip ratio of the lockup clutch or reduces a slip amount of the lockup clutch.

Abstract: A control device controls a lockup clutch interposed between an engine and an automatic transmission mechanism of a vehicle. The control device includes a control part supplying hydraulic pressure to the lockup clutch and controlling differential pressure of the lockup clutch. The control part supplies the hydraulic pressure to the lockup clutch so that the differential pressure is lower than a reference differential pressure in a disengaged state of the lockup clutch. In a case of shifting the lockup clutch from the disengaged state to an engaged state, the control part supplies the hydraulic pressure to the lockup clutch so that the differential pressure increases as a filling ratio of an oil passage of the lockup clutch decreases. The reference differential pressure is a lower limit of the differential pressure that increases a slip ratio of the lockup clutch or reduces a slip amount of the lockup clutch.

Abstract: A control method for an internal combustion engine which is a driving source of a vehicle in which a driving force is transmitted to a transmission when a clutch is engaged, the control method includes: when the internal combustion engine which is automatically stopped in a state where the clutch is disengaged is restarted, performing a torque down control to decrease a target torque of the internal combustion engine when the clutch is engaged; setting a predetermined torque release time period determined in accordance with a driving state; and ending the torque down control at a timing at which the torque release time period is elapsed from an engagement command of the clutch which is generated during the torque down control.

Abstract: A physical quantity measuring apparatus has: a plurality of physical quantity sensors of the same type, each of which detects a physical quantity at intervals of a predetermined length of time; a computing unit that calculates an output value according to physical quantities detected by the plurality of physical quantity sensors at each detection time; and a deciding unit that makes a predetermined decision according to an output value calculated about the immediately preceding detection time and to physical quantities detected by the plurality of physical quantity sensors at the current detection time. The computing unit calculates an output value at each detection time according to a decision result of the deciding unit.

Abstract: A control device for a lock-up clutch includes a control unit, an abnormality determination unit, a release control unit and a prohibition unit. The control unit is configured to control an engagement state of a lock-up clutch, and to perform a slip lock-up control by performing a feedback control of an engagement hydraulic pressure to be a first slip amount during coasting. The abnormality determination unit is configured to determine an abnormality when a state continues with a slip amount being equal to or greater than a second slip amount. The release control unit is configured to release the lock-up clutch when the abnormality is determined. The prohibition unit is configured to allow the control unit to raise the engagement hydraulic pressure by a prescribed pressure, and to prohibit determination by the abnormality determination unit, when the transmission ratio is downshifted during coasting while the slip lock-up control is performed.

Abstract: Methods and systems are provided for improving fuel economy by opportunistically lowering engine idle speed below a base idle speed when electrical loads are not present. A hydraulic brake pressure is increased when the idle speed is raised, in anticipation of vehicle propulsion. The brake pressure counteracts any creep torque and unintended vehicle acceleration resulting from the rising engine idle speed.

Abstract: In a vehicle equipped with a torque converter (4) having a lock-up clutch (3), learning control for obtaining a learning value (L_n) on the basis of meet-point information, with which the lock-up clutch (3) initiates torque transmission, is carried out. After acquiring the current learning detection value (M_n), a meet-point learning control unit (12c) calculates the current detection error (E_n) on the basis of the difference between the current learning detection value (M_n) and the previous learning value (L_(n?1)) that is stored. When the current and previous detection errors (E_n) and (E_n?1) have the same plus/minus sign, the current learning value correction amount is set to a larger value if the absolute value |(E_n?1)| of the previous detection error (E_n?1) is large than if the absolute value |(E_n?1)| is small. The sum of the previous learning value (L_(n?1)) and the current learning value correction amount is set as the present learning value (L_n).

Abstract: A control apparatus for controlling an automatic transmission including a torque converter to which a driving force of an engine is input includes a specifying unit configured to specify a drag torque of a wet friction type lock-up clutch, and a transmission unit configured to transmit load information including at least the drag torque specified by the specifying unit to a control apparatus of the engine. The specifying unit specifies the drag torque of the lock-up clutch during in-gear based on a slip ratio of the torque converter before in-gear when the lock-up clutch is released.

Abstract: Lock-up clutch engagement hydraulic pressure learning control can be precisely performed by starting lock-up clutch engagement control and executing the lock-up clutch engagement hydraulic pressure learning control after execution of shift control is completed, in a case where the lock-up clutch engagement control is limited in a shift stage before execution of the shift control, when the shift control is executed in a state where a multi-disc lock-up clutch is released. Meanwhile, a decrease in fuel efficiency performance and a direct steering feeling is minimized by starting the lock-up clutch engagement control during shift control in a case where the lock-up clutch engagement control is not limited.

Abstract: Systems and methods for operating a transmission of a hybrid powertrain that includes a motor/generator are described. The systems and methods may classify transmission degradation in response to an estimated transmission input shaft speed that is determined from transmission output shaft speed. In one example, transmission degradation may be correctable transmission degradation, partial transmission degradation, and continuous transmission degradation.

Abstract: A transmission includes a torque converter with both a variable pitch stator and a bypass clutch. These are controlled in two modes to maintain a target slip speed. In a first mode, the bypass clutch is fully released and slip is controlled by varying the pitch of the stator blades. In a second mode, the stator is held in the tightest position and slip is controlled by varying the torque capacity of the bypass clutch. The target slip is calculated based on a variety of different input signals depending on what type of vehicle maneuver is being performed.

Abstract: In a control apparatus for a vehicle, in the cases where engine torque is higher than first torque and an engine torque change amount is larger than a first torque change amount when control is shifted from complete engagement control of a lock-up clutch to deceleration slip control, an electronic control unit is configured to shift the control from the complete engagement control to acceleration slip control and then shift the control from the acceleration slip control to the deceleration slip control after the vehicle is brought into a driven state.

Abstract: A control device for a hybrid vehicle is, in the process of stopping an internal combustion engine of the vehicle, capable of making twist angle fluctuation reduction control and crank angle position control mutually compatible. When a request for stopping the internal combustion engine has been issued, twist angle fluctuation reduction control is implemented without implementing crank angle position control, until, in the process of bringing the engine to a stopped state, the rotational speed of the internal combustion engine drops below the resonant rotational speed region of the torsional damper; and, after the rotational speed of the internal combustion engine has dropped below the resonant rotational speed region of the torsional damper in the process of bringing the engine to a stopped state, crank angle position control is implemented without implementing twist angle fluctuation reduction control, until stopping of the internal combustion engine has been completed.

Abstract: A vehicle lock-up clutch control device is provided to suppress engine racing when a lock-up clutch is engaged at the time a vehicle starts moving. The vehicle lock-up clutch control device is provided with a control unit that delays the rise in lock-up command pressure if a line pressure, which is the source pressure of the actual lock-up oil pressure, is rising when the lock-up clutch is engaged at the time the vehicle starts moving. The control unit executes a torque reduction in the engine at least during the delay in the lock-up command pressure.

Abstract: A power transmission includes first and second clutches for switching a transmission path for a driving force therein. A clutch controlling unit provided for a work vehicle is configured to switch the transmission path from one to the other of first and second modes when a speed ratio parameter reaches a mode switching threshold. The clutch controlling unit is configured to keep setting the transmission path in the other mode even when the speed ratio parameter again reaches the mode switching threshold until a switching prohibition period having a predetermined initial value expires as long as a period of time elapsed after mode switching is included in the switching prohibition period. A trigger detecting unit provided for the work vehicle is configured to make the switching prohibition period expire when detecting a predetermined operation in the switching prohibition period.

Abstract: A vehicle control system configured to carry out an energy saving control is provided. The vehicle control system is applied to a vehicle having an engine, a torque converter, a transmission and a clutch device selectively connecting a turbine runner to the transmission. The vehicle control system executes the energy saving control by controlling both an operating condition of the engine and an engagement condition of the clutch device or only the engagement condition of the clutch device. The vehicle control system comprises a clutch control means configured to increase the torque transmitting capacity of the clutch device using an increasing amount of a speed of the turbine runner as a target value, when bringing the clutch device into engagement being in disengagement during execution of the energy saving control.

Abstract: An automatic transmission uses 6 shift elements applied in combinations of four to establish ten forward speed ratios and a reverse speed ratio. The automatic transmission uses a hydraulic control system to control engagement of the six elements, control engagement of a torque converter bypass clutch, control engagement of a parking pawl, and to provide fluid for a hydrodynamic torque converter and for lubrication. The parking pawl is disengaged in response to engagement of two of the six shift elements and remains disengaged in response to engagement of other shift elements. A single valve controls several different functions associated with the two-pass torque converter. Pressurized fluid is provided by a variable displacement engine driven pump and also by an electric pump. A priority valve reduces lubrication flow when other fluid demands are high as indicated by the pump displacement control circuit.

Abstract: A running control device of a vehicle including an engine, a connecting/disconnecting device separating the engine and wheels, and a transmission transmitting power of the engine toward the wheels, the running control device of a vehicle being configured to execute a normal running mode performed by using the power of the engine with the engine and the wheels coupled, a free-run inertia running mode that is an inertia running mode performed by separating the engine and the wheels and stopping the engine during running, and a neutral inertia running mode that is an inertia running mode performed by separating the engine and the wheels and operating the engine in a self-sustaining manner during running, the running control device of a vehicle setting a gear ratio of the transmission on a high vehicle speed side in the case of return from the free-run inertia running mode to the normal running mode.

Abstract: A clutch control system for vehicle is applied to a vehicle having a clutch and a transmission disposed in a power transmission path from an engine to a vehicle wheel. The system includes a first rotational speed detecting unit to detect a driving side rotational speed of the clutch, a second rotational speed detecting unit to detect a driven side rotational speed of the clutch, a half-clutch control unit, and a half-clutch transition control unit. The half-clutch control unit executes a first half-clutch control on the clutch actuator when a gear position of the transmission and a rotational direction of a driven side portion of the clutch are matched and executes, on the clutch actuator, a second half-clutch control, differing from the first half-clutch control, when the gear position of the transmission and the rotational direction of the driven side portion of the clutch are not matched.

Abstract: In a hydraulic control circuit including a solenoid valve, whose change responsiveness in an actual pressure with respect to a change in an instructional pressure deteriorates when the instructional pressure enters a dead band region on a lower pressure side than a dead band threshold, for adjusting a hydraulic pressure supplied to a hydraulic device operated by the hydraulic pressure based on the instructional pressure, the instructional pressure is increased in a stepwise manner to a charge pressure higher than the dead band threshold, when the instructional pressure is set in the dead band region and the instructional pressure increases within the dead band region to such an extent that a speed ratio does not change. Then, a lower limit of the instructional pressure is set to the dead band threshold, and use of the dead band region is prohibited for a certain period of time.

Abstract: A controller is provided with a lock-up capacity control means for controlling a lock-up capacity to a predetermined target capacity when a transition to a coast running state occurs, a timing means for measuring a time during which a slippage, which is a difference between a revolution speed (engine speed) of an input element and a revolution speed (turbine speed) of an output element, is within a predetermined range when the lock-up capacity is controlled to the predetermined target capacity, and a capacity learning means for making a learning-correction to the predetermined target capacity such that the time measured by the timing means is brought to a predetermined target time. By virtue of the learning-correction, it is possible to accurately control the lock-up capacity when the transition to the coast running state has occurred.

Abstract: A method and a system of learning an operation of an engine clutch using a hydraulic pressure sensor and a motor of a vehicle. The method includes determining, by a controller, whether power transmission of a transmission that transmits output from the engine and the motor has been interrupted and increasing, by the controller, pressure of the engine clutch to a target pressure with a predetermined ratio when the power transmission has been interrupted. In addition, measuring, by the controller, actual pressure of the engine clutch using a hydraulic pressure sensor when pressure of the engine is increased with the predetermined ratio to the target pressure and calculating, by the controller, a difference value between the measured actual pressure and target pressure. Furthermore, adjusting, by the controller, pressure of the engine clutch to correlate the actual pressure of the engine clutch to the target pressure based on the difference value.

Abstract: An internal combustion engine in a motor vehicle is automatically shut off and started by way of a start-stop device, wherein an automatic shut-off process is initiated during a coasting operation phase of the internal combustion engine, and an automatic start process is initiated when at least one activation command occurs. For shutting off the internal combustion engine in the coasting operation phase, a gas exchange in cylinders of the internal combustion engine is at least almost completely suppressed and, at the same time, a torque converter lock-up clutch disposed between the internal combustion engine and the transmission for power transmission purposes is actuated such that the torque converter lock-up clutch remains or is at least almost completely engaged.

Abstract: A control device of a vehicle provided with an engine, and a fluid-operated power transmitting device provided with a lock-up clutch and configured to transmit a drive force of said engine to drive wheels, and an engine connecting/disconnecting clutch configured to selectively place a power transmitting path between said engine and said fluid-operated power transmitting device in a power transmitting state and a power cutoff state, said vehicle being able to run in an engine drive mode in which said engine is operated as a vehicle drive power source while said engine connecting/disconnecting clutch is placed in a fully engaged state, comprising: a lock-up clutch control portion configured to bring said engine connecting/disconnecting clutch from the fully engaged state into a slipping state and temporarily place the engine connecting/disconnecting clutch in the slipping state while said lock-up clutch is placed in a slipping state, when a lock-up slip control is implemented to place said lock-up clutch from a

Abstract: In a method for diagnosing an operating status of a drive device in a drive system of a motor vehicle having at least two drive devices configured as an electric machine and an internal combustion engine, and having at least one separating clutch which couples the drive devices in an adjustable way, setpoint rotational speeds of the drive devices are set to predetermined values and the operating status is determined from the resulting actual rotational speed of the one drive device.

Abstract: The present disclosure provides systems and methods to detect and reduce any high driveline torsional levels, such as due to the cylinder deactivation in variable displacement system engines or aggressive lock-up strategies for fuel efficiency, in automobile transmissions. The present disclosure utilizes a controller in an automobile to operate a computationally thrifty method for quickly detecting noise and vibration disturbances in the transmission. This quick detection enables fuel economic calibrations that aggressively reduce the disturbances by controlling slip in a launch device of the transmission. As problem disturbances arise, they are detected before occupants notice objectionable behavior. Once detected, the disturbances are reduced, such as by increasing launch device slip, which effectively intercepts the objectionable disturbances before they are transferred through the entire drivetrain.

Abstract: In order to properly perform vibration damping control in a vehicle 1 in which vibration occurs due to driving characteristics, a vibration damping control device 10 performs sprung vibration damping control of suppressing sprung vibration generated in the vehicle 1, by control of the torque that is generated in wheels 5 of the vehicle 1, with this vibration damping control device 10 performing vibration damping control suppression control of stopping sprung vibration damping control, or reducing a control amount of sprung vibration damping control, on the basis of engine speed and engine torque of an engine 14 that is a power source of the vehicle 1 during travel. As a result, it becomes possible to prevent vibration damping control from being brought to an inappropriate state, due to a travel state of substantial vibration, during vibration damping control.

Abstract: A damper clutch control apparatus for an automatic transmission may include a driving information detection unit detecting driving information including a displacement amount of an accelerator pedal, an engine speed, an engine torque, and a rotation speed of a turbine, a control portion which receives the driving information and realize a release control of a damper clutch when a driver's intention for acceleration or deceleration of a vehicle may be detected in a state of connection of the damper clutch, and an actuator which controls hydraulic pressure supplied to the damper clutch so as to realize connection or release of the damper clutch according to a control signal received from the control portion.

Abstract: A first hydraulic pressure control unit forms an oil path to supply oil to a frictional engagement element when a select lever is located in a travel range or between the travel range and a non-travel range and forms an oil path to discharge the oil from the frictional engagement element when the select lever is located in the non-travel range. An abnormality determination unit cancels an abnormality determination when only a travel range signal is output from a range signal output unit after a signal of the range signal output unit is determined to be abnormal, and maintains the abnormality determination when only a non-travel range signal is output from the range signal output unit.

Abstract: According to the present invention, a starting clutch control system is configured to stop the engine while disengaging the clutch upon satisfaction of a predetermined condition when the vehicle is running, and restart the stopping engine while engaging the clutch upon satisfaction of a predetermined restarting condition. The starting clutch control system applied to a vehicle is configured: to estimate a turbine torque of the torque converter based on engine speed, and capacity coefficient and a torque ratio of the torque converter, when the engine is required to increase a power to be restarted; to increase a torque transmitting capacity of the clutch in accordance with the estimated turbine torque; to estimate the turbine torque based on an air intake of the engine and an engine speed after a completion of an engagement of the clutch; and control the torque transmitting capacity of the clutch with the estimated turbine torque.

Abstract: A device for controlling an automatic transmission including a lock-up clutch control portion and a zero slip control portion for bringing a lock-up clutch into a zero slip state immediately before slippage occurs in accordance with a zero slip request outputted during a non-gear shift, wherein in a case where a target slip amount is equal to or smaller than a slip amount threshold value upon transition to the zero slip state, the zero slip control portion fixes the target slip amount to the slip amount threshold value and retains the fixed target slip amount for a predetermined period of time, and after the predetermined period of time has elapsed, gradually decreases the target slip amount from the slip amount threshold value to a zero slip amount with a predetermined gradient with time.

Abstract: A variable channel type fan clutch apparatus may include a storage chamber and an operation chamber in which oil may be collected, wherein a fan clutch rotor may be interposed between the storage chamber and the operation chamber, an oil circulatory channel which fluid-connects the storage chamber and the operation chamber to circulate the oil therethrough, and a variable value which may be located in the oil circulatory channel, wherein the variable value may be configured to close the oil circulatory channel when an engine may be stopped or when a fan clutch exceeds an operation temperature, and wherein the variable value may be configured to open the oil circulatory channel when the engine may be operated or when the fan clutch does not exceed the operation temperature.

Abstract: A start control device and a start control method of a vehicular power transmission system including a lock-up clutch and a start clutch are provided in which start-time lock-up slip control is performed, and neutral control is performed. When the start-time lock-up slip control is additionally executed during cancellation of the neutral control, the gradient of an output rotational speed of the hydraulic power transmission which is changed, through engagement of the start clutch, toward an input rotational speed of the automatic transmission at the time of completion of engagement of the start clutch is controlled, using at least one of a start clutch pressure that is increased so as to engage the start clutch, and a lock-up clutch pressure that is increased so as to bring the lock-up clutch into slip engagement.

Abstract: A method of estimating transmission torque of a dry clutch, may include a) slowly releasing a dry clutch until a slip of the dry clutch occurs, b) acquiring and storing stroke of an actuator and torque of an engine at a starting time point at which the slip of the dry clutch occurs at step a), and c) determining the stroke of the actuator and the transmission torque of the dry clutch at the starting time point at which the slip of the dry clutch occurs, by using the stroke of the actuator and the torque of the engine stored at step b).

Abstract: A coasting control device capable of avoiding coasting control during turning is provided. A turning recognition unit that recognizes that a vehicle is turning and a unit for prohibiting coasting control during turning that prohibits coasting control when the turning recognition unit recognizes that the vehicle is turning are provided.

Abstract: A dynamic model is stored in memory that defines torque transmitted by a lockup clutch in a torque converter as a function of a plurality of torque converter operating parameters. A lockup clutch command to control engagement the lockup clutch is asserted, and thereafter a number of the plurality of torque converter operating parameters are monitored. The model is continually solved using the monitored operating parameters to determine torque transmitted by the lockup clutch over time, and a lockup clutch on-coming capacity signal is produced if the torque transmitted by the lockup clutch exceeds a torque threshold.

Abstract: A motorized vehicle includes a transmission system and an inch/brake device providing at least two ranges of motion. An engagement force of the transmission system is provided in a first range of motion of the inch/brake device, and a braking force of the motorized vehicle is provided in a second range of motion of the inch/brake device. An accelerator device moves between two or more positions, wherein moving the accelerator device from one position to another position causes an amount of overlap between the first and second ranges of motion of the inch/brake device to vary.

Abstract: A control device for controlling an engagement state of a lock-up clutch is provided. A plurality of target slip ratio maps include a normal slip ratio map having a characteristic line of a target slip ratio defined in accordance with an engine load at a normal vehicle running condition and a modified slip ratio map having a characteristic line of the target slip ratio to become a facing calorific value lower than a facing calorific value corresponding to the slip ratio retrieved from the normal slip ratio map. In the case where an estimate value of the facing temperature continues to exceed first threshold temperature for more than predetermined time when to carry out slip control using the normal slip ratio map, control to switch the target slip ratio map from the normal slip ratio map to the modified slip ratio map is carried out.

Abstract: A transmission includes a plurality of clutches that are selectively engageable alone or in combination with each other to establish a plurality of forward drive modes, wherein one of the clutches is configured as a neutral idle (NI) clutch that is selectively actuated to shift the transmission into an NI state, and a controller. The controller is adapted to shift the transmission from a forward drive mode into the NI state during a coast-down maneuver prior to the transmission reaching a zero output speed. A method of shifting the transmission into the NI state includes determining the presence of a predetermined one of the forward drive modes using the controller, and using the controller to actuate a designated one of the clutches as an NI clutch to enter the NI state during the forward drive mode, during a coast-down maneuver, and prior to the transmission reaching a zero output speed.

Abstract: Methods and systems are provided for reducing audible clunks and objectionable drive feel in vehicles including start/stop systems. In one example, a vehicle engine is shutdown during vehicle coasting. The vehicle engine is then restarted, while the vehicle is moving with a torque converter clutch disengaged. A transmission clutch pressure is then adjusted during the restart based on a torque converter output speed relative to a torque converter input speed.

Abstract: A clutch of a hydrodynamic torque converter, which connects the drive input of the hydrodynamic torque converter to the drive output of the hydrodynamic torque converter, is actuated in a disengaging direction when a power at an auxiliary power take-off in a vehicle exceeds a predefined value.

Abstract: A method and system for managing accumulator effects during engagement of a lockup clutch of a torque converter includes selecting a pump speed profile that reduces a rotational speed of a pump of the torque converter from an initial value to a rotation speed of a turbine of the torque converter. A pump acceleration profile is determined based on the pump speed profile. Engagement of the lockup clutch is controlled as a function of an inertia of an engine associated with the torque converter, a torque applied by the engine to the pump, the rotational speed of the turbine, the pump speed profile, and the pump acceleration profile.

Abstract: A method for ascertaining a rotational speed parameter for determining a setpoint torque for driving a drivetrain. The drivetrain comprises a first and at least one second drive assembly for driving a hybrid vehicle. The first drive assembly can be coupled to the drivetrain by means of a clutch. The second drive assembly is mechanically coupled to the drivetrain. When the hybrid vehicle is being driven by means of at least the first drive assembly, the rotational speed parameter corresponds to the value of a shaft rotational speed. When the hybrid vehicle is being driven only by means of the second drive assembly, the rotational speed parameter corresponds to the value of a determined rotational speed.

Abstract: A clutch of a hydrodynamic torque converter in which the input drive of the hydrodynamic torque converter can be connected to the output drive of the hydrodynamic torque converter. The clutch of the hydrodynamic torque converter is only engaged if a difference between the rotational speeds of the pump and the turbine of the hydrodynamic torque converter is not reached and a predefined distance traveled by the accelerator pedal is exceeded.

Abstract: A method of operating the torque converter lock-up clutch in a power transmission of a working machine comprising at least one hydraulically actuated lifting device. The torque converter lock-up clutch is actuated for disengagement when a predefined limit value for the position of the lifting hydraulic mechanism of the at least one lifting device is exceeded. When the position of the lifting hydraulic mechanism falls below a predefined limit value and when the turbine rotational speed exceeds a predefined threshold value, the torque converter lock-up clutch is reengaged.

Abstract: During a non-shift operation when a predetermined gear of an automatic transmission is kept, a hydraulic control unit increases an engagement hydraulic pressure to a friction engagement device associated with the gear formation by a predetermined hydraulic pressure with respect to a line hydraulic pressure. Therefore, in comparison with a case where a hydraulic pressure equivalent to the line hydraulic pressure is set as an engagement hydraulic pressure to the friction engagement device for obtaining a hydraulic pressure equivalent to the line hydraulic pressure, shift response (hydraulic pressure response) variations when shifting from a non-shift state (steady state) into a shift state are suppressed by the margin of the predetermined hydraulic pressure. In addition, in comparison with a case where the engagement hydraulic pressure to the friction engagement device is set to a maximum hydraulic pressure to reduce the response variations, power consumption of each linear solenoid valve is suppressed.

Abstract: When an inertia phase of an upshift of the transmission is started during a lockup clutch engagement operation, a following command oil pressure to be used during a following lockup clutch engagement operation is learned on the basis of a slip rotation speed, which is a rotation speed difference between an input side rotation speed of the torque converter and an output side rotation speed of the torque converter, at or after a start point of the inertia phase.

Abstract: A method for controlling torque converter slip includes operating the torque converter in a controlled slip mode, monitoring slip in the torque converter, statistically analyzing the monitored slip to determine a likely condition of the torque converter, and utilizing the likely condition of the torque converter to control the torque converter slip.

Abstract: A control apparatus for an automatic transmission system having a serial arrangement of a stepwise variable automatic transmission mechanism and a continuously variable automatic transmission mechanism, the control apparatus being disposed in the automatic transmission system and performing a shift control of the continuously variable automatic transmission mechanism in accordance with variation in transmission ratio of the stepwise variable automatic transmission mechanism, the control apparatus including a control section configured to execute a retardation processing upon shift control of one of the continuously variable transmission mechanism and the stepwise variable transmission mechanism which has a smaller response delay of an actual transmission ratio from a target transmission ratio than that of the other transmission mechanism.