Abstract: A method of changing gear in an automated transmission system of a motor vehicle having a multi-ratio gearbox with an input shaft and an output shaft, a take-up clutch located between the input shaft and an output shaft of an engine, a number of pairs of intermeshing gears.

Abstract: A transmission control system, includes:

Abstract: When a different speed change request occurs during pre-charging, an indicated pressure is stepwise changed up to a standby pressure for after pre-charge, and a processing in accordance with the different speed change request is commenced with the indicated pressure after the stepwise change, as an initial pressure.

Abstract: In the method, the transmission ratio of the speed transmission (i_act) is set automatically using stored adjustment characteristic curves, as a function of a variable (FP, tv) which characterizes the engine output, and a variable (v) which characterizes the vehicle speed. The transmission ratio is varied as required by means of a manual intervention by the driver. The transmission ratio of the speed transmission is set as a stepped deviation from a setpoint engine speed (n_eng).

Abstract: When a reshift request for a second shift to a second gear ratio is produced during a first shift operation to a first gear ratio in an automatic transmission, a reshift control apparatus performs a reshift operation in response to the reshift request in a first reshift control mode by terminating the first shift operation at an intermediate state without completing the first shift operation, and instead initiating the second shift operation from an intermediate state.

Abstract: In gear shift controlling method and apparatus for an automatic transmission, the automatic transmission comprising a plurality of frictional elements, a working liquid pressure for each of first and second frictional elements is controlled to make a gear shift in the automatic transmission in such a manner that while the first frictional element is released by a decrease pressure control for the working liquid pressure, the second frictional element is clutched by an increase pressure control for the working liquid pressure and a release capacity during an inertia phase during which the gear shift from a first gear range to a second gear range occurs is set in accordance with an instantaneous gear ratio during the inertia phase so as to output the release capacity set according to the instantaneous gear ratio.

Abstract: Described is a process for the adaption of the shifting operation of an automatic transmission. Accordingly, a determination of adaption values is made relative to occurrences shifting quality in the operation of an automatic transmission, and said determined values are stored in the memory of an adaption storage and can be accessed for the control of shifting operations. The determined adaption values prior to the storage in the adaption memory are corrected in respect to a lifetime loading of the automatic transmission.

Abstract: At the time of the change-speed, by correcting the torque reducing portion of an output shaft during the change-speed, the revolution number of an input shaft is controlled on the basis of the corrected torque reduction correcting value. Also, the torque of said input shaft is adjusted at the end of the change-speed on the basis of said torque correcting value.

Abstract: An apparatus and method for controlling a plurality of clutches in a powershift transmission. The transmission is coupled to an engine of an off-road vehicle. The method includes receiving a shift command having a shift direction. Clutch timing is selected based on the shift direction. Using the selected shift timing, on-coming clutches are engaged in sequence with disengagement of off-going clutches to achieve smooth shifting.

Abstract: A shift control system of an automatic transmission executes an interchange shift by interchanging engagement conditions of first and second friction elements of the automatic transmission. The first and second friction elements are engaged and disengaged according to oil pressures supplied thereto. A controller of the shift control system is arranged to decrease the second oil pressure of the second friction element by a second predetermined gradient and to increase the first oil pressure of the first friction element by a first predetermined gradient after the loss stroke of the first friction element is terminated, and to determine the first gradient such that a difference between a command pressure and an actual pressure of the first friction element is kept substantially constant.

Abstract: An automatic transmission controller carries out (a) changing a control for engaging the engaging-side frictional element between in a first condition in which a speed of progression in the shift is managed mainly in accordance with a volume of the hydraulic fluid to be supplied to the engaging-side frictional element itself and in a second condition in which the shift progresses regardless of the volume of hydraulic fluid to be applied to the engaging-side frictional element itself; and (b) accomplishing a volume control for the engaging-side frictional element from a timing immediately after a decision of the shift under a command hydraulic pressure of the hydraulic fluid to be supplied to the engaging-side frictional element in the second condition, the command hydraulic pressure having a lower limit value for securing that a piston stroke of the engaging-side frictional element completes within a predetermined time.

Abstract: Within the scope of the procedure for improvement of the shifting speed of automatic transmissions, at each gear shift at least one engaging or disengaging shifting element needed for the next gear shift in the same direction is prepared or lowered to shifting pressure during the gear shift in a manner such that when the synchronous rotational speed is reached, it is made possible immediately to carry out the next gear shift.

Abstract: A hydraulic control device for an automatic transmission capable of preventing engine racing and tie-up by controlling disengagement side oil pressure in accordance with an input torque and an oil temperature. Gear-change execution controller U4 controls drain timings T1 and T3 and a drain gradient &dgr;P of the disengagement side oil pressure acting on the frictional engagement elements of the disengagement side according to the magnitude of the input torque and elevation of the oil temperature in torque phase control wherein both the engagement side oil pressure and the disengagement side oil pressure are controlled.

Abstract: A hydraulic control system includes switching mechanisms for receiving as a signal pressure a hydraulic pressure which is output from each shifting mechanism when all units of the shifting mechanisms are caused to output a hydraulic pressure, and being responsive to the reception of the signal pressure to be switched to a predetermined state for blocking a hydraulic-pressure supply path to specific hydraulic servos, thereby achieving a specific speed out of a plurality of speeds; and supply switching mechanisms provided in a hydraulic-pressure supply path to a hydraulic servo which is not included in the specific hydraulic servos, for switching between supply and cut-off of the hydraulic pressure to the hydraulic servo so as to assure two speeds in the event of the signal failure in a hydraulic control system for individually controlling engaging elements in an automatic transmission by using electric signals.

Abstract: In a shift control method for an automatic transmission, it is first determined a signal for shifting from a reverse range to a drive range is input, then further determined if an engine is in an idle state. An initial shifting signal of a first duty ratio is output to a drive unit and maintained the first duty ratio for a first predetermined fill time. Next, the first duty ratio is reduced to a second duty ratio and outputting a signal of the second duty ratio for a soft engagement control to the drive unit, and it is determined if a current turbine rpm is less than a first predetermined value which is obtained by extracting a second predetermined value from a target turbine rpm. Next, a feedback duty control signal is output to the drive unit, and it is determined if a turbine rpm variation is higher than a third predetermined value or if the turbine rpm is less than a fourth predetermined value.

Abstract: Disclosed is a method for controlling runup comprising the steps performing upshifting from a second speed to a third speed if throttle opening and vehicle speed are at predetermined levels; determining if runup occurring at the point where upshifting from the second speed to the third speed is performed, the determination of the occurrence of runup being performed based on turbine rpm, transmission output rpm and a second speed gear ratio; determining if a time rate of change in turbine rpm is less than 0 if runup is occurring; reducing a duty for a predetermined time period if the time rate of change in turbine rpm is greater than 0; and performing feedback control if the time rate of change in turbine rpm is less than 0.

Abstract: A power Off upshift control method for an automatic transmission includes the steps of determining, during an upshift operation, if power Off upshifting is taking place; determining if power Off upshift conditions are satisfied; measuring a hydraulic pressure response time, establishing a maximum duty value for preventing forced shifting, and calculating the hydraulic pressure response time when the maximum duty value changes to 100% duty, these processes being performed if the power Off upshift conditions are satisfied; calculating a shift finish point after the hydraulic pressure response time is calculated; determining if the shift finish point corresponds to an actual shift finish point; and setting the maximum duty value at 100% duty if the shift finish point corresponds to the actual shift finish point.

Abstract: Shift valves 141, 142, 143 are provided to switch oil passage connections to a state in which an oil pressure in one hydraulic clutch of an arbitrary speed transmission train and an oil pressure in a hydraulic clutch of a transmission train which is adjacent thereto as seen in the order of speed are controllable by a pair of linear solenoid valves 201, 202. Skipped speed change from a predetermined first speed transmission train to a second speed transmission train which is not adjacent to the first speed transmission train is made possible. In concrete, a large-capacity accumulator A5 is connected to an oil passage L19 which is in communication with 5th-speed hydraulic clutch C5. At the time of skipped speed changing from 5th speed to 3rd speed, shift valves 141, 142, 143 are switched to a state of 3rd-4th speed change. The oil pressures in the hydraulic clutches C3, C4 for 3rd and 4th speed transmission trains, respectively, are made controllable by the linear solenoid valves 201, 202.

Abstract: An improved control for an automatic transmission closed-throttle downshift, wherein closed-throttle engine torque is used to raise the transmission input speed to the synchronous speed of the target speed ratio, and wherein the on-coming clutch is controlled in a manner to complete the shift with minimum driveline torque disturbance in spite of clutch control variability. The invention includes a primary on-coming clutch control for completing the downshift when the input speed reaches the synchronous speed, and a contingent on-coming clutch control that is initiated if shift completion is not achieved by the primary control, the contingent control being effective to re-establish input speed synchronization and thereupon engage the on-coming clutch to complete the shift.

Abstract: The invention concerns a process and a device for engine and transmission control in a motor vehicle with an internal combustion engine controlled by an engine control and a stepped automatic transmission controlled by a transmission control.

Abstract: A shift control apparatus comprises clutches driven by shift solenoids and whether or not the raising of the rotation speed occurs in an internal combustion engine is determined. If the raising of the engine rotation speed is detected, a hydraulic pressure learn correction is made to engagement hydraulic pressure and a time learn correction is made to the hydraulic pressure supply preparation time. The correction ratio of the energization-hydraulic pressure characteristic (I-P characteristic) of clutch clearance and the shift solenoid is set so as to become an appropriate distribution ratio and the learning is started based thereon.

Abstract: An improved control for an automatic transmission upshift, wherein the on-coming clutch pressure (Ponc) is scheduled during the torque and inertia phases of the shift in accordance with the summation of feed-forward and feed-back control terms, the feed-forward control term being developed using an inverse dynamic model of the transmission. The feed-forward control term is determined by developing a desired acceleration trajectory of the input shaft, and periodically applying the acceleration trajectory to the inverse dynamic model to obtain an estimate of the required on-coming clutch pressure, given the transmission input torque. The feed-back control term is based on a comparison of the expected input speed response with the actual input speed response, and corrects for modeling errors in the feed-forward control, providing disturbance rejection and improved command following.

Abstract: A method of controlling a clutch pressure of a transmission which can be applied to a clutch of a large capacity piston volume, which has a short time lag for engaging the clutch, a uniform clutch engaging time and is inexpensive, and a control apparatus therefor.

Abstract: An improved transmission upshift control in which the off-going clutch is controlled to emulate the behavior of an ideal free-wheel device to thereby achieve nearly ideal timing of the off-going clutch disengagement relative to the on-coming clutch engagement. During the preparation phase of the shift, the off-going pressure is reduced in proportion to the estimated volume of fluid supplied to the on-coming clutch such that the off-going pressure is at a calibrated value when the on-coming clutch is filled. However, the calibrated value is adjusted upward in direct relation to the transmission input torque above a given level so as to emulate the reaction torque that would be exerted by an ideal free-wheel device for maintaining the current speed ratio. The torque phase of the control commences when the estimated volume indicates that the on-coming clutch is completely filled.

Abstract: A control apparatus for an automatic transmission capable of sufficiently producing the effect of neutral control by reducing a period of time from stop of a vehicle to the release of an input clutch. Vehicle stop prediction means for predicting immediate stop of the vehicle from a vehicle speed detected by a vehicle speed sensor is provided. Input clutch control means for reducing a hydraulic pressure in a hydraulic servo of the input clutch from a hydraulic pressure in a normal engagement state to a waiting pressure capable of maintaining an engagement state of the clutch based on the prediction of the stop of the vehicle by the vehicle stop prediction means is provided. The operation of releasing the input clutch concurrent with the neutral control is started from a state of the waiting pressure, so that the input clutch is released in a short period of time.

Abstract: A hydraulic control system includes switching mechanisms for receiving as a signal voltage a hydraulic pressure which is output from each shifting mechanism when all units of the shifting mechanisms are caused to output a hydraulic pressure, and being responsive to the reception of the signal pressure to be switched to a predetermined state for blocking a hydraulic-pressure supply path to specific hydraulic servos, thereby achieving a specific speed out of a plurality of speeds; and supply switching mechanisms provided in a hydraulic-pressure supply path to a hydraulic servo which is not included in the specific hydraulic servos, for switching between supply and cut-off of the hydraulic pressure to the hydraulic servo so as to assure two speeds in the event of the signal failure in a hydraulic control system for individually controlling engaging elements in an automatic transmission by using electric signals.

Abstract: In an automatic transmission for conducting a gear change by replacing friction engagement elements, a transmission torque capacity of an engage side friction engagement element at a torque phase is corrected based upon a change amount per unit time of a turbine rotation speed at the torque phase or a torque phase time.

Abstract: An improved on-coming clutch fill control method in which a model of the transmission hydraulic system is used for control purposes to accurately predict the achievement of on-coming clutch torque capacity based on a comparison of the modeled volume of supplied fluid to a reference volume representing the actual volume of the on-coming clutch, and in which the reference volume for each type of shift is adaptively adjusted based on input speed aberrations observed during shifting. If input speed flaring occurs due to an underestimated reference volume, the reference volume is adaptively increased based on the volume of fluid supplied to the on-coming clutch between the initial detection of flaring and a detection of maximum flaring.

Abstract: An improved shift control for a hydraulic automatic transmission in which the apply chamber of an on-coming clutch is filled in the preparation phase of the shift using a hydraulic flow rate model to estimate the volume of hydraulic fluid supplied to the apply chamber. In an initial portion of the fill interval, fluid is supplied to the apply chamber at a first elevated pressure, while continuously updating the fluid volume estimate. When the remaining un-filled volume of the apply chamber reaches a reference volume, the supply pressure is reduced to a second pressure at which the next phase of the shift is to be carried out. When the chamber volume is filled, the torque capacity of the clutch rises to a level corresponding to the second pressure, and the next phase of the shift automatically ensues.

Abstract: Quick shifting is achieved while preventing a shift shock when shifting is caused by grip change of four engagement elements. The automatic transmission requires activation of the four engagement elements when shifting from a first shifting position (sixth speed) to a second shifting position (third speed) is performed. This shifting control apparatus includes shift control means for starting disengagement of a second engagement element after starting disengagement of a first engagement element; completing engagement of a fourth engagement element after completing engagement of a third engagement element; and starting disengagement of the second engagement element before completing engagement of the third engagement element.

Abstract: To relatively precisely detect the start of torque phase for relatively precisely restraining speed shift shock caused by torque interference in clutch to clutch speed shift, an output from an input shaft rotational speed sensor at a reduction gear unit is passed through a secondary Butterworth high pass filter which is a digital filter having a cutoff frequency of 1.0 Hz to remove a change component caused by acceleration of the vehicle. A filter output Ni_fil which is a change component by generation of transmission torque of an engaged side clutch is thus provided. When this filter output Ni_fil falls to less than a first threshold value of −ref1 and thereafter becomes less than a second threshold value of −ref2 without recovering to be equal to or higher than the first threshold value of −ref1, it is determined to be the start of the torque phase.

Abstract: A power Off upshift control method for an automatic transmission includes the steps of: a) determining if a vehicle is under conditions requiring power Off upshift control; b) starting power Off upshift duty control if the conditions are satisfied; c) calculating average turbine rpm change rate; d) measuring turbine rpm changing period and determining if the turbine rpm changing period is greater than a predetermined value; e) calculating a shift finish point if the turbine rpm changing period is greater than the predetermined value; f) determining if the turbine rpm change rate is less than a value obtained by adding a mapping value to the turbine rpm change rate; g) determining if the turbine rpm value is greater than or equal to the shift finish point, if the turbine rpm change rate is greater than the mapped value in the previous step; h) producing a shift finish point duty rate if the turbine rpm value is greater than or equal to the shift finish point; i) determining if the turbine rpm is less than a ta

Abstract: Disclosed is a shift control method for automatic transmissions.

Abstract: A torque-based clutch engagement controller for achieving smooth friction clutch engagement in a multiple-ratio transmission for an automotive vehicle driveline comprising a torque measuring circuit that determines torque inputs for the controller as a function of measured engine torque and turbine acceleration, means for determining the torque commanded by the vehicle operator as a function of engine throttle position, means for comparing the desired torque commanded by the operator to the input torque values, and means for converting the torque values to a pressure value as a function of the difference between the desired torque and the input torque whereby the pressure developed by the system applies a friction clutch so that engagement of the clutch occurs rapidly with optimum smoothness.

Abstract: A method and apparatus for providing first and second automatic shift modes for an automatic transmission. Shifting of the automatic transmission is controlled by a transmission controller. The driver selects a control mode by manipulating an input device. The controller controls the operation of the automatic transmission using a first set of operating characteristics and a second set of operating characteristics in response to receiving the first mode signal and the second mode signals, wherein the first and second sets of operating characteristics include engine management characteristics.

Abstract: To minimize a delay time of the start of the control of a solenoid valve for changing gear ratios of a transmission, the need for a speed change is judged and when the speed change is needed, a control cycle of the solenoid valve is made longer than the control cycle in the steady state.

Abstract: In a control unit of an automotive vehicle, it is possible to securely prevent a tie-up due to a miss-recognition of a disengage timing of a disengage side friction device, securely prevent an early disengage due to an erroneous recognition of the disengage timing and realize a control of accurately and reliably shifting the clutch.

Abstract: A setting device for a front control system for a construction machine includes a direct setting switch for instructing a direct teaching setting, a numeral input key consisting of up- and down-keys for instructing a numeral input setting, a setting changeover switch for changing over a setting mode from the direct teaching setting to the numeral input setting, an LED lighting up when the setting changeover switch is pushed, an area limiting switch for starting an area limiting excavation control, an LED lighting up when the area limiting switch is pushed, and a display screen for indicating the position of a bucket end of a front device in terms of a numeral value when the setting changeover switch is not pushed, and indicating the numeral value input with the numeral input with the numeral input setting when the setting changeover switch is pushed.

Abstract: The present invention provides a method for shifting from a first gear state to a second gear state which holds one element at a predetermined level until the second reaches its fill volume. In this method, one element is applied while the other element is released. The element which reaches its fill volume first is held at a control limit. This control limit is defined by a volume between the first clutch element and a predetermined point above the fill volume of the first clutch element. This clutch element is then maintained at within the control limit until the other clutch element reaches its fill volume. The maintained clutch element is then released shortly after the other clutch element has reached its fill volume. This method ensures that neither fighting or slipping occurs between the two elements.

Abstract: An automatic transmission control system controls locking pressure for locking a specific friction coupling element to a target level previously determined according to engine output torque and appropriately changes the target level such that, when an increase in engine output torque occurs, a delay of a locking pressure change relative to an engine output torque change becomes greater after the target level has reached near an appropriate level than before it has reached near the appropriate level.

Abstract: The present invention provides a method for shifting from a first gear state to a second gear state which holds one element at a predetermined level until the second reaches its fill volume. In this method, one element is applied while the other element is released. The element which reaches its fill volume first is held at a control limit. This control limit is defined by a volume between the first clutch element and a predetermined point above the fill volume of the first clutch element. This clutch element is then maintained at within the control limit until the other clutch element reaches its fill volume. The maintained clutch element is then released shortly after the other clutch element has reached its fill volume. This method ensures that neither fighting or slipping occurs between the two elements.

Abstract: A control system for an automatic transmission includes a fluid transmission unit connected to an engine; a clutch; a hydraulic servo; output RPM detector for detecting the output RPM of the fluid transmission unit; oil pressure generator for generating the oil pressure fed to the hydraulic servo; and a control unit. The control unit includes a booster for raising the oil pressure according to preset characteristics; change rate detector for detecting the RPM change rate of the output RPM in a preset range at the application of the clutch; and a corrector for correcting the preset characteristics by comparing the detected RPM change rate and a reference RPM change rate. The change rate detector detects the RPM change rate only when the output RPM at the time of starting the engagement of the clutch is higher by a preset value than the maximum of the output RPM in the preset range.

Abstract: A process is provided for operating a vehicle transmission with preferably electrohydraulically actuatable friction elements for shifting between different transmission steps, in a vehicle with at least one drive engine in which an actual value of at least one of the quantities characterizing the shift process is determined for each shift process, which actual value is compared with a theoretical value that can be established and stored. When the actual value deviates from the theoretical value, a regulated quantity for at least direct influencing is changed by a correction value that can be established. For each shift process, the time duration for the output of a gear shift signal up to the beginning of the synchronization process and/or the change of the drive rpm during this time period is determined as a first and/or second actual value of the quantity characterizing the process.

Abstract: A fuzzy control method of a damper clutch and, more particularly, a fuzzy control method enhances engine brake effect by directly connecting a pump to a turbine by engaging the damper when a shift control unit identifies an engine brake state. The fuzzy control method of a damper clutch includes receiving or checking input signals relating to a damper clutch; controlling shift timing by a fuzzy control; determining if an engine brake should be used or not; checking an amount of driver's engine brake will if the engine brake should be used; determining if an emergency brake should be used or not; engaging the damper clutch when an emergency brake should be used; and controlling the damper clutch through a normal control when both the engine brake and emergency brake are not used.

Abstract: A method and system for calibrating at least one clutch in a transmission whereby the incipient engagement pressure of the fluid in the clutch may be determined. Two shafts in the transmission are locked together in mutually incompatible gear ratios thereby preventing their free relative rotation. The output of the clutch is connected to these shafts to prevent its free rotation. The input of the clutch is connected to the engine to cause it to rotate. The clutch is then gradually engaged as the load on the engine is monitored, preferably by measuring changes in the fuel flow rate to the engine. Once the engine load increases a predetermined amount, the system saves the particular valve command signal that produced the incipient engagement pressure and the process ends. The method is preferably performed entirely under microprocessor control, thereby eliminating the need for operator intervention during the process.

Abstract: Upshifting is performed in a short time without giving rise to shocks. For that purpose, at the time of upshifting, a hydraulic pressure (QUPOFF) of a hydraulic engaging element on disengaging side is controlled such that the input and output speed ratio ("Gratio") of a transmission is decreased to, and held at, a predetermined slipping region (YG(N)S) that is lower than an engaging region (YG(N)L)-YG(N)H) to be set based on a gear ratio which is established by the engagement of the hydraulic engaging element on the disengaging side. The hydraulic pressure (QUPON) of a hydraulic engaging element on engaging side is gradually increased. When "Gratio" once falls below YG(N)L and then increases up again to YGCONOK, QUPOFF is lowered to a predetermined low pressure (QUPOFFB) at a lapse of a predetermined time (YTMUP8). Once "Gratio">YGCONOK, QUPON is increased to a predetermined high pressure QUPONB at a lapse of a second predetermined time YTMUP3.

Abstract: Both shocks and time lag at the time of gear-in are reduced. For that purpose, the hydraulic pressure of a hydraulic engaging element to be engaged at the time of gear-in (in-gear pressure) QING is increased relatively rapidly at the beginning of gear-in. The speed of increase of QING is lowered after the input and output speed ratio "Gratio" of a transmission has exceeded a predetermined value YINGS which works as a basis for discriminating the start of engagement of the hydraulic engaging element.

Abstract: A system for controlling an automatic vehicle transmission, including a gear system and hydraulic clutches which hold a member of the gear system stationary to produce gear reduction or reverse, having an oil line which connects the clutches to an oil pressure source, a pressure control valve having a solenoid provided in the oil line which generates a regulated oil pressure to be supplied to the clutches in response to a current supplied to the solenoid, a switch valve provided in the oil line which switches the oil pressure to be supplied to the one of the clutches between the regulated oil pressure and a line pressure. In the system, it is discriminated whether the pressure control valve does not supply the regulated oil pressure to the clutches and if so, a dither current is supplied to the solenoid such that the valve repeatedly performs a vibrational motion to remove any grit therefrom, thereby removing grit without causing gear-shift shock or clutch vibration.

Abstract: In a method for the production of actuator signals as a function of sensor signals in an open-loop and/or closed-loop control system, the sensor signals are read into a data processing device and converted into internal input signals. The internal input signals are evaluated together with stored status information with the use of predetermined functions, whereby internal output signals and possibly new status information to be stored result. Actuator signals are derived from the internal output signals and fed to at least one actuator.

Abstract: A control system for an automatic transmission, in which a first frictional engagement element and a second frictional engagement element are released according to a shift from a running range to a non-running range. The shift from the running range to the non-running range is detected, and the reduction in the oil pressure of the second frictional engagement element is controlled on the basis of the reduction in the oil pressure of the first frictional engagement element when the shift from the running range to the non-running range is detected.