Abstract: The invention proceeds from a control of the drive train of a motor vehicle having at least a drive unit and an automatic transmission. During driving operation, a desired value for the drive torque of the vehicle or for the transmission output torque is pregiven by the driver. The different operating points of the drive train are characterized by at least different output torques of the drive unit and rpm ratios and/or different output rpms of the drive unit. The essence of the invention is that, during driving operation, a set of evaluation quantities is determined for each possible operating point. One of the possible operating points is then selected as an optimal operating point via an optimization method based on the determined evaluation quantities. The transmission ratio, which belongs to this selected optimal operating point, is then adjusted on the transmission.

Abstract: In a disengagement side control, in a power on state, a disengagement side pressure P.sub.W is output, P.sub.W being set higher than a base pressure dependent on input torque, and a disengagement side frictional engagement element is engaged and maintained. In a power off state, a disengagement side pressure lower than the base pressure is output, and the disengagement side frictional engagement element slips. In the disengagement side control, when the vehicle driving state is changed from the power off state to the power on state, the disengagement side pressure P.sub.W is changed from that for a slip state to that for a maintain state.

Abstract: A vehicle drive train includes an automatic transmission, which has an automatic shift mode and a manual shift mode. The transmission is operable in the automatic shift mode and also operable in the manual shift mode. An input device has a manual select lever. A controller receives an operator mode change demand from the input device and conditions the automatic transmission for operation in one of the automatic and manual shift modes in accordance with the operator mode change demand after a predetermined condition has been met. The predetermined condition is met when the pending shift that is in progress is completed.

Abstract: A vehicle speed control system comprises a section for calculating a command driving force-required to make a sensed vehicle speed equal to a preset command vehicle speed, a section for calculating a command engine output in accordance with the command driving force and the command vehicle speed, a section for calculating a command engine speed corresponding to the command engine output from a predetermined engine torque-versus-speed characteristic relationship in an engine constraint state of minimum throttle setting and fuel cutoff inhibition when the command driving. force is negative, and a section for calculating a command transmission ratio in accordance with the command engine speed. When the driving force command is negative, the control system put the engine in the constraint state and controls a continuously variable transmission in response to the command transmission ratio so as to prevent undesired vehicle speed hunting.

Abstract: A system for changing the gear ratio with a multi-step reduction gear, where a flywheel is accelerated or decelerated during a change in gear ratio. The flywheel, consisting essentially of engine components and the converter, must be accelerated in downshifting operations, for example, while the flywheel is decelerated in upshifting operations. To change the gear ratio, at least two different selectable strategies are given. A first value representing the engine output torque and a second value representing the torque demand for acceleration or deceleration of the flywheel are detected first. To change the gear ratio, one of the above-mentioned strategies is then selected, depending on a comparison of the first value detected with the second value detected. To determine the engine output torque in the actual shifting operation, it is predicted from the instantaneous load signal and parameters that depend on the throttle valve angle.

Abstract: A combined engine and transmission control unit for a motor vehicle uses the position of the accelerator pedal to calculate setpoint values for the engine and the transmission of the motor vehicle. The control unit has a drive-train controller, which, when the engine is not in traction mode, controls the driving mode of the motor vehicle. The driving mode is adapted to the surroundings of the motor vehicle and the driving style of the driver. The drive-train controller activates an engine torque control when brake slip is detected, and the transmission controller prescribes a lower gear than is provided for the unbraked mode of the motor vehicle by a characteristic diagram.

Abstract: A controller (100 in FIG. 1) for relieving a gear shift shock in a vehicle, comprising an input torque calculation portion (131) which calculates the input torque (T.sub.t) of the stepped automatic transmission mechanism of the vehicle from engine r.p.m. (N.sub.e) and turbine r.p.m. (N.sub.e), a shift start recognition portion (134) which recognizes the real mechanical shift start timing of the stepped automatic transmission mechanism in accordance with the change of the input torque (T.sub.t), a line-pressure correction magnitude calculation portion (142) which calculates a line-pressure correction magnitude (.DELTA.PL) during the gear shift operation of the stepped automatic transmission mechanism when the shift start has been recognized, a standard line pressure calculation portion (143) which calculates a standard line pressure (PL), and a command line pressure calculation portion (144) which adds the line-pressure correction magnitude (.DELTA.

Abstract: A controller (100 in FIG. 1) for relieving a gear shift shock in a vehicle, comprising an input torque calculation portion (131) which calculates the input torque (T.sub.t) of the stepped automatic transmission mechanism of the vehicle from engine r.p.m. (N.sub.e) and turbine r.p.m. (N.sub.e), a shift start recognition portion (134) which recognizes the real mechanical shift start timing of the stepped automatic transmission mechanism in accordance with the change of the input torque (T.sub.t), a line-pressure correction magnitude calculation portion (142) which calculates a line-pressure correction magnitude (.DELTA.PL) during the gear shift operation of the stepped automatic transmission mechanism when the shift start has been recognized, a standard line pressure calculation portion (143) which calculates a standard line pressure (PL), and a command line pressure calculation portion (144) which adds the line-pressure correction magnitude (.DELTA.

Abstract: The invention is directed to a method and an arrangement for controlling an output torque of a drive train of a motor vehicle. A desired value for the output torque is made available by the adjustment of a transmission and by the control of the engine. The desired value is determined on the basis of a driver command signal as well as on the basis of a minimum and/or maximum output torque dependent upon operating variables.

Abstract: A system for controlling air flow to an engine cooling system includes a control computer responsive to a number of engine and/or engine accessory operating conditions, and to various engine operational states to control operation of an engine cooling device. The engine operational states are each a function of at least engine fueling commands and include a "free energy" state corresponding to zero fueling, an "absorbing additional torque" state corresponding to zero fueling and activation of either service brakes or engine brakes, and a "needs additional torque" state corresponding to a rapid positive change in fueling, recent gear shifting to the lower gears of the transmission with fueling above a predefined level or a high rate of change in fueling rate. All other engine operational states are defined as a don't care state.

Abstract: The invention relates to a safety system for a motor vehicle having an internal-combustion engine. Independent quantities are used for engine control and for monitoring the engine control. Control of the internal-combustion engine is performed, for example, by way of an operating parameter characterizing the engine load, while monitoring of the engine control is performed by means of the output torque. Preferably, monitoring of the engine control is integrated into a traction control system, in which case desired and actual values for a quantity characterizing the vehicle propulsion, such as the output torque, are transmitted by the engine control to the monitoring system and are compared there for recognizing a fault. If a fault is recognized in the traction control system, a signal is transmitted back to the engine control unit, to influence the engine control.

Abstract: A motor vehicle wherein the clutch is automatically engaged to initiate a creeping movement of the vehicle when the engine is on, the transmission is in gear, the gas pedal is not depressed and the brake or brakes is or are not applied. This entails or takes place at least substantially simultaneously with an increase of the engine torque. If the creeping movement is interrupted, e.g., as a result of the application of a brake, the clutch is disengaged and the engine torque is reduced.

Abstract: In an automatic transmission, torque shocks are effectively reduced in specific downshifting conditions where relatively strong engine braking occurs as a result of downshifting. When a downshift command to the automatic transmission is detected when an accelerator pedal is not depressed, a valve opening command is issued to a throttle valve so that engine output will have increased by the time the downshifting action of the automatic transmission actually begins, ignition timing is delayed so that an increase in engine output resulting from the opening of the throttle valve by a throttle valve control means is offset for a period starting at the time the engine output actually increases as a result of the opening of the throttle valve by the throttle valve control means and ending at the time the downshifting action of the automatic transmission actually beings, and the ignition timing delaying is cancelled upon initiation of the downshifting action of the automatic transmission.

Abstract: An engine powertrain control device is configured to reduce data amounts of characteristics of a torque converter and realize torque estimation with high accuracy. A device detects or computes rotating speeds of input and output shafts of the torque converter. A device computes a ratio (speed ratio) between the rotating speed of the input shaft and the rotating speed of the output shaft of the torque converter. A device stores data of a pump capacity coefficient and torque ratio product of the torque converter and computes a value of the product corresponding to a value of the speed ratio computed above, and a device is provided for computing an output shaft torque of the torque converter by using the value of the computed product.

Abstract: A process is described for shifting a gear change transmission which has no synchronizing members. A defined rotational speed difference is adjusted at the gear clutches in the range of the synchronous rotational speed. Thereby engaging flanks of the clutch halves which are always situated opposite to one another in the same rotating direction come in contact during the shifting.

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: A gearshift controller for an automatic transmission comprises an input shaft torque estimating portion for estimating the input shaft torque, a torque dividing ratio setting portion for setting the torque dividing ratio for each friction member of each gear range, and a desired torque calculating portion for calculating the desired torque of each friction member on the basis of the input shaft torque and the torque dividing ratio, and a desired hydraulic fluid calculating portion for calculating the desired hydraulic fluid pressure for each friction member on the basis of the desired torque of the each friction member, and a hydraulic fluid controlling portion for providing the desired hydraulic fluid pressure to each friction member.

Abstract: A vehicle having an antilock brake system to control a brake so as to suppress locking of wheels when a slip ratio of the wheels exceeds a predetermined value is also provided with a continuously variable transmission (CVT). When antilock brake control is being performed, a drive shaft torque controller computes a command torque of an engine and command drive ratio of the CVT so that a drive shaft torque is a predetermined torque. An engine controller controls the engine according to the command torque and a CVT controller controls the transmission according to the command drive ratio.

Abstract: A gear availability indicator for multi-gear transmissions of motor vehicles includes a signal processing unit for receiving input signals representative of vehicle speed and engine speed. The signal processing unit can determine a gear ratio value representative of the relationship between vehicle speed and engine speed for each gear in the vehicle transmission and can generate output signals for operation of a display. The display includes a first section displaying a range of acceptable engine speeds and a second section displaying gear symbols representative of gear ratio values. The displayed range of acceptable engine speeds and the displayed gear symbols are relatively moveable. The mutual alignment of the displayed range of acceptable engine speeds and one or more of the displayed gear symbols indicates that one or more gears represented by the one or more gear symbols are available for engagement in the transmission.

Abstract: A method is provided for adaptively determining a torque-related (K-factor) value for a torque converter in a vehicle and providing adaptive torque management to an automatic transmission. The torque-related K-factor value is computed for a given torque converter as a function of engine speed and difference in torque measured with the vehicle operating in idle neutral and drive. The vehicle dynamically learns the K-factor value and manages torque applied to the transmission by limiting the engine output speed as a function of the learned torque-related K-factor and vehicle speed.

Abstract: A method and apparatus for controlling a transmission for use with an automotive vehicle including an engine. The transmission coupled to the engine for transmitting a torque inputted thereto from the engine to produce an output torque at a continuously variable speed ratio. A target value for the speed ratio is calculated based on vehicle operating conditions. A rate at which the speed ratio changes to the calculated target value is calculated. An upper limit for the rate is calculated to satisfy such a condition that the output torque is substantially equal to or greater than zero. The rate of change of the speed ratio is limited to the upper limit when the calculated rate of change of the speed ratio is greater than the upper limit.

Abstract: In an automatic transmission, torque shocks are effectively reduced in specific downshifting conditions where relatively strong engine braking occurs as a result of downshifting. When a downshift command to the automatic transmission is detected when an accelerator pedal is not depressed, a valve opening command is issued to a throttle valve so that engine output will have increased by the time the downshifting action of the automatic transmission actually begins, ignition timing is delayed so that an increase in engine output resulting from the opening of the throttle valve by a throttle valve control means is offset for a period starting at the time the engine output actually increases as a result of the opening of the throttle valve by the throttle valve control means and ending at the time the downshifting action of the automatic transmission actually beings, and the ignition timing delaying is cancelled upon initiation of the downshifting action of the automatic transmission.

Abstract: An output torque control system for an internal combustion engine for a vehicle is responsive to a stepping-on amount of the accelerator pedal, for controlling output torque from the engine. Upon detection of an operation for starting the vehicle, the output torque from the engine is inhibited from being controlled to an increased value in response to the stepping-on amount of the accelerator pedal over a predetermined time period. It is determined that the operation for starting the vehicle has been carried out, when the accelerator pedal has been stepped on and a change in the shift position of the automatic transmission has occurred.

Abstract: A control for a vehicle fitted with an internal combustion engine as a power source. At the time of a driver deceleration intention (when travelling downhill), then with an arrangement where the opening control for the throttle valve and the fuel supply control (fuel cut off control or the like) are automatically controlled in order to obtain a predetermined target vehicle acceleration, when the intention of the driver shifts from a deceleration intention to a non deceleration intention, and hence the automatic control reverts to normal control, the fuel supply control is returned to normal control once the throttle valve opening has reached a predetermined opening. In this way, it is possible to avoid the situation where for example, the fuel supply control reverts to normal control with the throttle valve opened more than necessary. Consequently the occurrence of shock or an unintended acceleration due to a mismatch in the throttle opening at the time of reverting to normal control can be suppressed.

Abstract: A system and method for detecting tampering with a vehicle speed sensor input signal include determining a current gear ratio, comparing the current gear ratio to at least one reference gear ratio to determine a gear ratio difference value, and generating an error signal indicating tampering with the vehicle speed sensor signal when the gear ratio difference value exceeds a first threshold. In one embodiment the step of generating an error signal is performed only when the gear ratio difference value exceeds the first threshold for an elapsed time greater than a predetermined time period. One embodiment includes determining a current engine speed, current vehicle speed, and current transmission gear ratio and storing values for the current engine speed, vehicle speed, and transmission gear ratio in the memory whenever at least one predetermined criterion is satisfied.

Abstract: An apparatus for controlling an automotive vehicle having an engine whose output is controllable independently of an accelerator pedal operation. The apparatus including an engine output increasing device for temporarily increasing the engine output upon a shift-down action of an automatic transmission during vehicle deceleration. An engine output increase amount determining device is provided for determining an amount of increase of the engine output by the engine output increasing device on the basis of a deceleration value of the vehicle and according to a predetermined relationship between the engine output increase amount and the vehicle deceleration value.

Abstract: Engine speed control during garage shift maneuvers of a transmission coupled, via a transmission input shaft, to a driven turbine of a hydrodynamic converter, the driven turbine fluidically coupled to a driving pump of the converter, the pump coupled to an engine output shaft, wherein engine output torque is controlled in response to a deviation in turbine acceleration away from a target turbine acceleration, to minimize rate of change in turbine acceleration (jerk) during the garage shift maneuver, so as to reject engine torque load changes that may result in undesirable engine speed variation.

Abstract: A control device of an automatic transmission comprises a controller which detects accel off caused by the release of accelerating owing to the accel stamping in which lock-up clutch is released, and which proceeds command which releases the operation thereof or releases temporally the operation thereof to an exhaust brake device when it is decided that the exhaust brake is in operation. When accel off is suddenly conducted at the time of accelerating in which the lock-up clutch is not engaged the phenomenon in which the speed ratio at the torque converter is prevented from occurring by releasing the exhaust brake by the controller. Accordingly, the engaging operation of the lock-up clutch is conducted easily and it is possible to let the engine brake work. When the down shift of the automatic transmission or accel off is conducted a the time of using the exhaust brake, it is possible to conduct the engagement, of the lock-up clutch easily and let the engine brake work effectively.

Abstract: A control system for an internal combustion engine for an automotive vehicle increases the output torque of the engine during an upshift of the automatic transmission so as to reduce a shock generated during the upshift. Time periods are measured over which respective speed clutches of the automatic transmission have been disengaged. The timing of increasing the output torque of the engine during the upshift of the automatic transmission is changed, based on one of the time periods measured over which one of the speed clutches of the automatic transmission to be selected for the upshift has been disengaged.

Abstract: An automatic transmission control system, during a down shift, translates practical input speed to an transmission into a restrained input speed defined by a specific relationship which presents a difference between the practical and restrained input speeds greater when a changing rate of practical input speed is high as compared with when it is low, and forces an engine to continuously produce an output torque drop until the restrained input speed attains a specified speed level.

Abstract: Disclosed is a driving torque control device for a vehicle comprising the elements. The device can effectively suppress fluctuation of engine torque. (1) Means for calculating a torque control timing to determine and output at least two control timings of an engine torque generated by an engine during speed shifting. (2) Means for calculating and outputting an engine torque control quantity in response to the output from said torque control timing calculating means to calculate and output the engine torque control quantity (3) Means for controlling the engine torque during speed shifting in response to the outputs from said engine torque control quantity calculating means.The engine torque is reduced by a certain quantity at a first timing of said engine torque control timings, followed by increasing the engine torque at the second engine torque control timing, and then returning the engine torque to the engine torque of the time immediately before the first engine torque control timing.

Abstract: A controller (100 in FIG. 1) for relieving a gear shift shock in a vehicle, comprising an input torque calculation portion (131) which calculates the input torque (T.sub.t) of the stepped automatic transmission mechanism of the vehicle from engine r.p.m. (N.sub.e) and turbine r.p.m. (N.sub.e), a shift start recognition portion (134) which recognizes the real mechanical shift start timing of the stepped automatic transmission mechanism in accordance with the change of the input torque (T.sub.t), a line-pressure correction magnitude calculation portion (142) which calculates a line-pressure correction magnitude (.DELTA.PL) during the gear shift operation of the stepped automatic transmission mechanism when the shift start has been recognized, a standard line pressure calculation portion (143) which calculates a standard line pressure (PL), and a command line pressure calculation portion (144) which adds the line-pressure correction magnitude (.DELTA.

Abstract: Engine-control device, in which an internal combustion engine coupled to a transmission group is controlled by a central electronic unit which receives at an input a plurality of information parameters measured in the engine and calculates control signals for operating groups of the engine itself. The device comprises an external processing unit communicating with a control circuit of the transmission group and with the central control unit. The processing unit is capable of being activated by commands originating from the control circuit to modify the control signals, regulating alternately the torque generated by the engine and the speed of rotation of the engine itself.

Abstract: The invention provides a torque feedback shift control device for an engine control system including an engine, an engine torque controller, an automatic transmission for changing output speed of the engine, and a transmission controller for controlling gear shifting in the transmission. A target torque generator is provided for generating a signal indicative of a target torque pattern in shifting of the automatic transmission according to a shifting signal from the transmission controller. A drive shaft torque detector detects an output torque of the automatic transmission, and the engine controller performs feedback control of the engine torque so that the output torque detected by the drive shaft torque detector in downshifting of the automatic transmission follows up the target torque pattern.

Abstract: A controller (100 in FIG. 1) for relieving a gear shift shock in a vehicle, comprising an input torque calculation portion (131) which calculates the input torque (T.sub.t) of the stepped automatic transmission mechanism of the vehicle from engine r.p.m. (N.sub.e) and turbine r.p.m. (N.sub.e), a shift start recognition portion (134) which recognizes the real mechanical shift start timing of the stepped automatic transmission mechanism in accordance with the change of the input torque (T.sub.t), a line-pressure correction magnitude calculation portion (142) which calculates a line-pressure correction magnitude (.DELTA.PL) during the gear shift operation of the stepped automatic transmission mechanism when the shift start has been recognized, a standard line pressure calculation portion (143) which calculates a standard line pressure (PL), and a command line pressure calculation portion (144) which adds the line-pressure correction magnitude (.DELTA.

Abstract: In an arrangement for the cyclic adaptation of a characteristic for the changes in an automatic gearbox, a gear-change strategy which determines correction values by an algorithm that correlates external influencing variables and by a process involving evaluation of measured actual values of the influencing variables is used to adapt the characteristic both in the direction of the coordinate indicating a parameter dependent on the speed of travel and in the direction of the coordinate indicating a parameter associated with the engine torque. The process of adaptation is performed as a function of respectively associated correction values.

Abstract: A controller (100 in FIG. 1) for relieving a gear shift shock in a vehicle, comprising an input torque calculation portion (131) which calculates the input torque (T.sub.t) of the stepped automatic transmission mechanism of the vehicle from engine r.p.m. (N.sub.e) and turbine r.p.m. (N.sub.e), a shift start recognition portion (134) which recognizes the real mechanical shift start timing of the stepped automatic transmission mechanism in accordance with the change of the input torque (T.sub.t), a line-pressure correction magnitude calculation portion (142) which calculates a line-pressure correction magnitude (.DELTA.PL) during the gear shift operation of the stepped automatic transmission mechanism when the shift start has been recognized, a standard line pressure calculation portion (143) which calculates a standard line pressure (PL), and a command line pressure calculation portion (144) which adds the line-pressure correction magnitude (.DELTA.

Abstract: A method and an engine control for suppressing vibration in the drive train of a motor vehicle include detecting a variable being dependent on a speed of an engine, deriving and evaluating a gradient from the variable, reducing a torque of the engine by varying an ignition angle if impermissible vibration is detected, and controlling the torque reduction as a function of an upper and a lower threshold value for the gradient. An ignition intervention is carried out for reducing the engine torque if the gradient is below the lower threshold. The ignition intervention is cancelled if the gradient exceeds the upper threshold value. First lower threshold values are stored in a first performance graph, and second higher threshold values are stored in a second performance graph to which a switchover is made after a first tripping of an anti-bucking function.

Abstract: A shift by wire transmission system enables a driver to manually select a next desired gear and the system completes the shift automatically without requiring the driver to operate the clutch. The system includes an electronic transmission control unit that communicates with an electronic engine control unit to control engine speed during a shift in order to synchronize the speed of an engine shaft and the transmission shaft. The driver manually chooses a gear shift by moving a shift lever to thereby produce electrical signals indicative of the desired change in gears. Multiple or skip shifting is possible along with a method of automatically choosing a default gear in the event that the vehicle transmission is placed in neutral while the vehicle is in motion.

Abstract: An apparatus and method for controlling the torque on the power train of a machine is disclosed. The power train includes an engine and a torque converter. The machine includes a work implement that is moveable in response to the actuation of a plurality of hydraulic cylinders. An electronic controller determines an optimal engine speed based on the actual engine speed, torque converter output speed, and the fluid pressure associated with the hydraulic cylinders. The optimal engine speed is used to govern the speed of the engine to control the power train torque.

Abstract: A signal detector is located before an automatic transmission for detecting timing such that torque outputted from a torque converter of the automatic transmission at the moment of upshifting changes from clutch before shift to clutch after shift. A signal detector is located after the automatic transmission for detecting timing such that torque outputted from a torque converter of said automatic transmission at the moment of downshifting changes from clutch before shift to clutch after shift. An apparatus executes the driving shaft torque control in response to the changes in both torque signal detectors.

Abstract: A vehicle automatic transmission control system in which the clutch is controlled in a slipping state if a torque converter is locked up when the gear shift command is not output. When the engine speed fluctuates, the fluctuations pass through the transmission and wheels and act on the ground to produce a reaction which passes back through the wheels and vehicle body and acts on the passengers as surging. In the prior art, this surging is prevented by slip-controlling the lockup clutch. This complicates the hydraulic control circuit. In the subject control, therefore, the clutch is slip-controlled even when no gearshift is in progress so as to absorb surging by slipping the clutch, not by the torque converter as in the prior art. As a result, it suffices to control the lockup clutch L of the torque converter between only two positions, one for complete lockup and one for complete release, rendering the structure of the hydraulic control circuit simple.

Abstract: A drive device comprises a gearbox (1) of the motorcycle type in which a selector shaft (10), via its angular position, enables the gear ratio in which the gearbox will be engaged to be determined. The device is provided with an electronic control device (DCE) designed to automatically place the gearbox (1), or in other words the selector shaft (10), in the position corresponding to the gear selected by the driver or automatically determined as a function of the speed of the vehicle. The electronic control device (DCE) comprises, in particular, means for down-shifting gently despite the absence of a synchronizer in the gearbox.

Abstract: In an ignition timing controller used in conjunction with an internal combustion engine of a vehicle provided with a mechanism for igniting fuel, the running condition of the engine is detected and the optimum ignition timing is determined based on the running condition. It is determined also whether or not the vehicle is accelerating, and the variation rate of engine speed during acceleration is detected. When the variation rate is a positive value which is equal to or greater than a predetermined value, the ignition timing is retarded by a predetermined amount relative to the optimum ignition timing. When the variation rate is less than this predetermined value, the correction amount is set to zero so that the timing is not retarded. In this way, forward/backward oscillation of the vehicle based on rotational vibration of the crankshaft during acceleration from coasting, is suppressed.

Abstract: A cylinder valve control stem for a vehicle drivetrain including a transmission and an engine having a variable valve control mechanism which can vary valve lift diagram in response to a control signal. A controller develops the control signal in response to varying operating condition of the engine. The controller derives, upon initiation of a shift in the transmission, engine speed to be established after completion of the shift and corrects the control signal such that the variable valve control mechanism provides one of various valve lift diagrams whose predetermined value in engine speed is not exceeded by the derived engine speed.

Abstract: A control system serves for surely preventing occurrence of a shift shock due to engagement of a one-way clutch with an automatic transmission in non-shift condition, and comprises a disengagement detecter for detecting disengagement of the one-way clutch; a power-on detecter for detecting change in an operation of the engine from driven mode to drive mode; a throttle opening detecter for detecting a throttle opening of the engine; a throttle opening estimater for estimating a second throttle opening when a predetermined time has elapsed from the time at which the operation of the engine is changed from driven mode to drive mode, on the basis of a first throttle opening detected when the operation of the engine is changed from driven mode to drive mode; and a torque down instructer for generating a torque down signal for reducing the output torque of the engine when the estimated second throttle opening is not less than a predetermined reference value.

Abstract: An interactive cruise control system and method for providing automatic speed control of a vehicle with improved shifting of an automatic transmission. The system and method controls speed of a vehicle equipped with cruise control and minimizes downshifts in an automatic transmission of the vehicle. Vehicle speed is detected and compared with a setpoint speed which is associated with the cruise control system. Transmission gear shifting is determined based on predetermined shift schedule points. Determined transmission gear downshifts are prevented for a kickdown delay period based on vehicle speed loss and the presence of vehicle deceleration. Also provided is an overspeed reduction method for causing a transmission downshift during an overspeed condition with the throttle closed. Further, the system provides hunting prevention between both second gear and third gear as well as between third gear and fourth gear of a four speed automatic transmission.

Abstract: An automatic engine stop-start system automatically stops an engine to reduce the fuel consumption whenever a predetermined condition is fulfilled and automatically starts the engine whenever another predetermined condition is fulfilled. This system is particularly arranged to detect gearshift lever position of an automatic transmission to determine various automatic stop/start conditions so that an engine in a car with an automatic transmission can be automatically stopped/started.

Abstract: A lock-up controller of a lock-up control system reads-in a vehicle speed V, a throttle opening degree TVO, an engine speed Ne, and a turbine speed Kt from sensors and outputs a fuel-out command and a fuel-supply restart command to an engine controller, to operate a lock-up clutch in a torque converter of an automatic transmission for an automotive vehicle in an accelerator-off (coasting) state of the vehicle. The lock-up control system makes it possible to realize locking-up of the torque converter providing an improved fuel consumption ratio of the engine and a large braking force from the engine, even when a vehicle speed increases due to running down a downward slope while the accelerator-off state continues, or when an up-shifting speed change occurs due to the accelerator-off state.

Abstract: A change gear control device is provided for an automatic transmission in a motor vehicle propelled by an internal combustion engine which is operated with an air/fuel mixture having air/fuel ratios ranging from a fuel rich air/fuel ratio to a fuel lean air/fuel ratio depending on driving conditions of the motor vehicle. In this device a first detector detects an engine torque of the internal combustion engine and a second detector detects a vehicle speed of the motor vehicle. A processor processes transmission gear ratios for the automatic transmission.