Abstract: A control system and control method for an automotive vehicle having a multiple-ratio automatic transmission having two gearsets arranged in series relationship for delivering vehicle engine power to vehicle traction wheels, each gearset being controlled using friction elements that establish multiple torque flow paths, each gearset being characterized by at least two ratios, which define an overall transmission ratio, synchronous shifting of the gearsets effecting at least one swap-upshift and at least one swap-downshift in the overall transmission ratio, the control system compensating during a swap-shift progression for dynamic interaction between the gearsets.

Abstract: A vehicle control apparatus generates an appropriate driving force according to the will of a driver when an internal combustion engine is restarted from a condition in which the idling of the engine is being stopped. In a condition in which the idling of an internal combustion engine 11 is being stopped, in the event that the depressing amount of a brake pedal by the driver is relatively large, an ECU (20) selects a relatively low-speed side gear of a transmission (15) so as to connect an input shaft (15A) and an output shaft (15B) together, and in contrast, in the event that the depressing amount of the brake pedal by the driver is relatively small, the ECU (20) selects a relatively high-speed side gear of the transmission (15) so as to connect the input shaft (15A) and the output shaft (15B) together.

Abstract: A transmission system includes a Central Processing Unit (CPU) that controls truck braking energy by sharing energy dissipation between clutch packs. The CPU reduces engine speed and then slips the two clutch packs at the same time to maintain a reduced turbine speed for a torque converter. In another aspect of the transmission system, energy loss is reduced during high draw bar pull conditions. The engine speed is modulated to trim energy peaks at low pushing or pulling speeds. An additional transmission gear reduction restores the lost pushing or pulling forces while generating less heat in the torque converter.

Abstract: There is provided a control system for a vehicle, which is capable of increasing the service life of a transmission belt while preventing slippage thereof, and at the same time improving fuel economy and drivability. The control system for a vehicle sets a transmission transfer torque to be transmitted from a drive pulley of a continuously variable transmission to a driven pulley of the same, and a clutch transfer torque to be transferred by a clutch. When it is determined that the vehicle is traveling on a bad road, the clutch transfer torque is reduced, and the transmission transfer torque is set to a larger value as the clutch transfer torque is larger.

Abstract: A method for controlling the gear release in an automated multi-speed drive in a vehicle drive with a drive motor and a separating clutch positioned between the drive motor and the multi-speed drive that the events “application of a shifting power” and “opening of the separating clutch” are determined dependent on reaching certain vehicle accelerations (agear—release, aclutch—engage). The vehicle acceleration (aveh) decreases at the beginning of the shifting process due to the reduction of the fuel injection quantity (EM) supplied to the drive motor.

Abstract: A vehicle transmission system includes a transmission component that has an engaged condition where torque can be transferred from a vehicle engine to a drive component, and a non-engaged condition where torque is prohibited from being transferred to the drive component. A controller generates control signals to control whether the transmission component is in the engaged or non-engaged condition. The controller also identifies when a vehicle start maneuver is a coast start based on vehicle conditions existing just prior to or during the vehicle start maneuver. When a coast start is identified, the controller generates a control signal to either disengage the transmission component or to maintain the transmission component in the non-engaged condition until engine speed generally matches transmission component speed. The controller can directly control engagement by automatically actuating a movable transmission member or can indirectly control engagement by controlling engine speed.

Abstract: A method and a device for detecting the clutch state in a motor vehicle, in particular during engine drag torque regulation, is described. A particularly simple and cost-effective method of detecting the clutch state is made possible by determining the engine speed and a wheel speed and by calculating a gear ratio therefrom. Threshold values for the overall gear ratio are stored in the system for at least each of the lower gears (e.g., the first through the third gear). The clutch state may be identified by comparing the calculated overall gear ratio with the threshold values of the particular gear.

Abstract: The present invention discloses a preferred method for operating a adaptive clutch system of the type used in a motor vehicle power transfer assembly by employing a dithered control signal. One aspect of the present invention superimposes a dithering signal onto a control signal by nulling consecutive blocks of control signal pulses. Another aspect of the present invention provides a method for generating a dithered control signal by providing a wave function with which to systematically vary a duty cycle of the dithered control signal. A method for varying the output force of a clutch actuator assembly in response to the dithered control signal is also provided.

Abstract: A transmission control system, includes: 1) a high speed side friction element for establishing a high speed side change gear; and 2) a low speed side friction element for establishing a low speed side change gear. After a disengagement of the high speed side friction element, the low speed side friction element makes an engagement for carrying out a downshift from the high speed side change gear to the low speed side change gear. When the downshift is carried out with an accelerator turned off, a stepping on the accelerator sensed in a period between the following times: i) a time for commanding a start of a transmission, and ii) a time for the low speed side friction element to start a conveyance of a torque, prevents a changeover to the low speed side change gear, thus keeping the high speed side change gear.

Abstract: An automated clutch of a motor vehicle is controlled according to a method with the steps: a) determining a first engine rpm-gradient signal (dnm(M)/dt) based on an engine torque signal (Me) and a target value (Mk) of the clutch torque; b) determining an engine rpm-rate signal (nm(R)) based on the engine rpm-gradient signal from step a); c) comparing an actual engine rpm-rate (nm) to the engine rpm-rate signal (nm(R)) from step b) and determining a correction quantity K based on the comparison; and d) correcting the first engine rpm-gradient signal (dnm(M)/dt) with the correction quantity K.

Abstract: A method and unit for controlling a clutch powered by a hydraulic actuator having a work chamber connected to a solenoid valve; a target value of the pressure of the fluid inside the work chamber is generated, an actual value of the pressure of the fluid inside the work chamber is measured, and a control signal for controlling the solenoid valve is calculated using feedback control of the pressure of the fluid inside the work chamber; and the target value of the pressure of the fluid is generated on the basis of an actual value of the position of the hydraulic actuator, and of a target value of the position of the hydraulic actuator.

Abstract: A vehicle driving force control apparatus is configured for a four-wheel drive vehicle that switches between a four-wheel drive state and a two-wheel drive state. The driving force control apparatus improves the response when a vehicle shifts into a four-wheel drive state while starting to move from a state of rest and, simultaneously, avoids the occurrence of shock when the clutch is connected. When the rotational speeds of the motor and the rear wheels reach or fall below their respective minimum detectable rotational speeds, the controller calculates estimated times until the motor and the rear wheels will stop based on the rotational speeds detected up until the minimum detectable rotational speed was reached and begins counting down from those estimated times. Since the clutch is connected after both estimated times have reached zero, the clutch is connected while reliably avoiding the occurrence of shock.

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

Abstract: A method of controlling the clutches of a dual clutch transmission during a two-gear positive downshift, wherein the first clutch drives an initial gear and the final gear and the second clutch drives an intermediate gear. The torque transfer across each clutch is controlled so that the torque output of the transmission will be linearly changed over from the first clutch to the second clutch to cause the engine to track a target engine speed profile. The method changes over the gears driven by the first clutch from the initial gear to the final gear as the engine continues to tracks the target speed. The torque transfer across each clutch is controlled so that the torque output will be linearly changed back from the second clutch to the first clutch in an inversely proportional rate to continue to cause the engine to track the target engine speed profile.

Abstract: In a differential limiting torque control section, a target differential rotation speed between front and rear drive shafts is established according to a dial position inputted by a driver of a variable dial. Further, an actual differential rotation speed between front and rear drive shafts is calculated and a deviation between the target differential rotation speed and the actual differential rotation speed is calculated. Based on the deviation, a first differential limiting torque and based on a dial position of a variable dial a second differential limiting torque are calculated. Further, a third differential limiting torque is calculated based on the dial position and a throttle opening angle. A final differential limiting torque between front and rear drive shafts is obtained by summing up these first, second and third differential limiting torques.

Abstract: A torque converter (1) comprises a pump impeller (1a) and turbine runner (1b) which transmit a torque via a fluid, and a lockup clutch (2) which engage the pump impeller (1a) and turbine runner (1b) according to an oil pressure. The pump impeller (1a) is connected to an engine (21), and the turbine runner (1b) is connected to an automatic transmission (23). An oil pressure control valve (3) supplies oil pressure to the lockup clutch (2) according to a signal from the controller (5). The controller (5) calculates a rotation speed increase rate of the turbine runner (1b) (S1), and controls the oil pressure of the oil pressure control valve (3) under a pressure increase rate which increases as the rotation speed increase rate (S10) increases, thereby preventing rotation speed fluctuations of the engine (23) accompanying lockup of the lockup clutch (2).

Abstract: The present invention discloses a preferred method for operating a adaptive clutch system of the type used in a motor vehicle power transfer assembly by employing a dithered control signal. One aspect of the present invention superimposes a dithering signal onto a control signal by nulling consecutive blocks of control signal pulses. Another aspect of the present invention provides a method for generating a dithered control signal by providing a wave function with which to systematically vary a duty cycle of the dithered control signal. A method for varying the output force of a clutch actuator assembly in response to the dithered control signal is also provided.

Abstract: A control system and method of operating a vehicle prime mover to control a centrifugal clutch is provided. The control system includes a control unit for receiving signals (THL) corresponding to a throttle operating parameter value. The control unit is configured to map the throttle operating parameter value to a predetermined throttle operating parameter value and sets an operating mode of the prime mover based on the predetermined throttle operating parameter value. The invention provides, among other things, a smooth, controllable engagement of the centrifugal clutch.

Abstract: An integrated vehicle engine/transmission control apparatus for an automotive vehicle having an engine capable of changing an operating speed thereof by itself, and an automatic transmission operatively connected to the engine and including a lock-up clutch, the apparatus including a lock-up clutch control device operable to control an engaging force of the lock-up clutch, during a shifting action of the transmission, for reducing a shifting shock of said automatic transmission, and a engine speed control device operable to control the engine so as to reduce its operating speed, during the shifting action of the transmission, such that reduction of the engine speed is initiated after a moment of initiation of reduction of the engaging force of the lock-up clutch by the lock-up clutch control means.

Abstract: An automatic shift controller for a vehicle which controls a gear-shifting mechanism to engage one of several gear trains. A sub-clutch connects and disconnects so that one of the gear trains, other than a first-speed gear train and a reverse gear train, is engaged or disengaged. By use of a controller, 1) when the vehicle is parked, then the reverse gear is engaged, the main clutch is engaged, and the sub-clutch is disengaged, and 2) when preparation for engine start-up is started in a state wherein the vehicle is parked, then the main clutch is disengaged and the sub-clutch is engaged.

Abstract: A method for controlling the safety mode of a four-wheel drive to control the magnetic clutch at a safety mode duty to reduce overload for a predetermined period of time when the slip of the magnetic clutch is greater than an allowable slip, despite controlling the magnetic clutch at its maximum duty.

Abstract: In a method for controlling an automated clutch and/or an automated transmission in a motor vehicle with an electronic clutch management system, a target value for the clutch torque is determined as an output quantity of a start-up function dependent on suitable input quantities.

Abstract: A method for controlling slip in an EMCC equipped torque converter is provided. The method determines whether an EMCC slip rate exceeds a predetermined RPM, determines whether a crankshaft RPM acceleration exceeds a predetermined rate, reduces an output torque of an engine in response to one of said EMCC slip rate exceeding said predetermined RPM and said crankshaft RPM acceleration exceeding said predetermined rate; and disables said output torque of an engine in response to said EMCC slip rate being less than said predetermined RPM and said crankshaft RPM acceleration being less than said predetermined rate.

Abstract: A center differential limiting control unit calculates and sets a vehicle speed, a target difference in a rotational speed between front and rear axle shafts, a control start difference in the rotational speed, and an actual difference in the rotational speed, respectively. Then, when the actual difference is large than the control start difference, it is determined that a front and rear axle shaft control start condition is established, and front and rear axle shaft differential limiting torque is calculated according to the actual difference and the target difference. In contrast, when the actual difference is smaller than the control start difference, it is determined that the front and rear axle shaft control start condition is not established, and an integral term in the front and rear axle shaft limiting torque and control is set to 0.

Abstract: A control unit for controlling an internal combustion engine in a motor vehicle passes through an initialization phase after power-on. To start the internal combustion engine, the internal combustion engine is synchronized with the control unit.

Abstract: The invention relates to a drivetrain having an automatic clutch.

Abstract: In a motor vehicle driveline including a transfer case whose output is continually connected to a first output, a clutch, operating partially engaged, responds to a control signal to change the degree of clutch engagement, whereby a second output is connected driveably to the first output. A digital computer, repetitively executing a computer readable program code algorithm for operating the clutch partially engaged, continually selects a desired magnitude of clutch engagement with reference to functions indexed by vehicle speed and either engine throttle position or engine throttle rate. The computer repetitively updates at frequent intervals the desired degree of clutch engagement, and issues a command clutch duty cycle to a solenoid-controlled valve, which signal changes the degree of clutch engagement in response to the command signal.

Abstract: A method of controlling the torque transferred across each clutches of a dual clutch transmission during a gear shift. The method includes the steps including determining when a shift has been commanded, sensing the speed of the driven member of the off-going clutch, determining the desired clutch torque and slip profile for the changeover of the clutches, and sensing the speed of the driven member of the on-coming clutch to determine a target engine speed profile. The method simultaneously controls the torque transfer across each clutch by linearly decreasing the torque transferred across the off-going clutch while linearly increasing the torque transferred across the on-coming clutch in an inversely proportional rate. Finally, the pressure applied to the on-coming clutch is varied, to cause the engine to continue to track the target engine speed profile so that vehicle speed is maintained.

Abstract: A method of controlling the pressure applied to the engaged clutch of a vehicle having a dual clutch transmission to control the torque transferred across the engaged clutch thereby providing engine speed control for each gear based on the engine throttle position. The method includes the steps of determining the engine throttle position, determining the currently engaged gear of the transmission, and sensing the speed of the clutch. An engine stall speed is selected for the current gear and engine throttle position from a look-up table, and then a target engine speed based on the engine stall speed and the clutch speed is continuously redetermined, the clutch speed increasing in response to the increasing engine speed.

Abstract: The vehicle comprises an engine (1), a transmission (8) connected to the engine (1), a detecting device (23) for detecting the current vehicle speed, a detecting device (26) for detecting the current gear position of the transmission (8), and a controller (10). The controller (10) functions to set the difference between the maximum drive force of the vehicle at the current vehicle speed and transmission gear position, and the running resistance at the current speed as the spare drive force; to set the difference between the current drive force of the vehicle and the running resistance at the current vehicle speed as the excess drive force; and to control the engine (1) or the transmission (8) so as to reduce the ratio of the excess drive force to the spare drive force.

Abstract: An automatic friction clutch in a drive train of a motor vehicle is controlled to transfer a clutch torque that includes an engine torque-dependent component and a clutch slip-dependent component.

Abstract: A control system for a transmission comprising a torque converter or a hydrodynamic clutch in a motor vehicle, at least one torque-conducting clutch or brake in the starting operation of the motor vehicle. It is proposed to regulate the starting power of the motor vehicle as function of a driver's wish, via a slip clutch or brake mounted in the transmission, taking into account parameters of the torque converter and/or hydrodynamic clutch.

Abstract: Power train control unit 100 controls friction clutch 203 when shifting from one cogwheel row to the other cogwheel row, sets the target synchronous rotation speed based on the output rotation speed of a transmission and parameters indicative of the state of engine 1 or the transmission, and sets the command value to the friction clutch so that the input rotation speed can be synchronized with the target synchronous rotation speed. Control unit 100 sets the target shifting required time based on parameters indicative of the state of engine 1 or the transmission, and corrects the command value to the friction clutch so that the required shift time can approach the above target shift required time.

Abstract: A method for controlling and/or adjusting a torque transmission system in the drive chain of a vehicle, especially a motor vehicle, wherein a clutch torque is modified according to a starting resistance of the vehicle in order to provide a strategy for the start of said vehicle. According to the invention, said strategy is modified in such a way that the progression of said clutch torque is adapted to a starting situation.

Abstract: In a power transmission, which adjusts and transmits the rotational output of an engine by the engagement control of a starting clutch 5, the rotational speed Ne and the suction negative pressure Pb of the engine are measured while the starting clutch is being actuated from a disengaged condition to an engaged condition with the engine being operated under a constant operational condition. An engagement-control value is calculated for the starting clutch when there is a change in the rotational speed and the suction negative pressure being measured, and the engagement-control value calculated is stored as an initial control value for starting an engaging action of the starting clutch. This initial control value is used for controlling the engagement of the starting clutch.

Abstract: A function controls the longitudinal clutch which determines a compensation of different rotational wheel speeds on the left or right vehicle side and, as a function of a permissible difference value, sets a constant torque at the longitudinal clutch.

Abstract: A method of calibrating an equilibrium position of an actuator driven by an electric motor with the assistance of a compensating spring, wherein the actuator moves a mechanism and the mechanism opposes the movement with an elastic force, and wherein in the equilibrium position the compensating spring counterbalances the elastic force, includes the following steps:

Abstract: An automated clutch of a motor vehicle is controlled according to a method with the steps:

Abstract: When changing gear, engagement side clutch coupling force of an automatic transmission (32) is controlled in response to an engagement side clutch coupling force control amount set in advance in an engagement side clutch coupling force control amount storage section (36). A disengagement side clutch coupling force control amount calculating block (40) has a physical model of the automatic transmission (32) internally. This disengagement side clutch coupling force control amount calculating block (40) then calculates disengagement side clutch coupling force control amount from a transmission input torque estimation value estimated by a transmission input torque estimation block (34), a running resistance estimation value from a running resistance estimation block (38) and engagement side clutch coupling force control amount using the physical model, and controls the automatic transmission (32) using the calculated disengagement side clutch coupling force control amount.

Abstract: In a method and apparatus for diagnosing a malfunction in a clutch actuator of a motor vehicle, the actual position of the clutch actuator is measured by a position sensor. Simultaneously, an estimated position of the clutch actuator is calculated by an emulation unit that emulates the function of the clutch actuator. Malfunctions of the clutch-actuator are diagnosed by comparing the actual, measured position to the estimated position.

Abstract: A hydraulic clutch (12, 13) transmits driving torque in a power train of a vehicle. An oil pressure supply unit (35) which supplies oil pressure for engagement to the clutch (12, 13) and a controller (40) which controls the unit (35) are provided. The controller (40) causes the unit (35) prior to engagement of the clutch (12, 13) to precharge the interior of the clutch (12, 13) with hydraulic fluid. The controller (40) counts an elapsed time since the last release of the clutch (12, 13) and shortens the precharge period as the elapsed time decreases, thereby optimizing the precharge state of the clutch (12, 13).

Abstract: A control system and method of operating a vehicle prime mover to control a centrifugal clutch is provided. The control system includes a control unit for receiving signals (THL) corresponding to a throttle operating parameter value. The control unit is configured to map the throttle operating parameter value to a predetermined throttle operating parameter value and sets an operating mode of the prime mover based on the predetermined throttle operating parameter value. The invention provides, among other things, a smooth, controllable engagement of the centrifugal clutch.

Abstract: A system is described for minimizing engine torque disturbances that would otherwise cause degraded drive feel by a vehicle driver. The system utilizes multiple torque transmission paths of a transaxle unit mounted to the engine. The system manipulates the torque transmitted by adjusting the clutches of multiple torque transmission paths so that the torque disturbance in the engine results in relatively constant vehicle drive torque. In particular, during particulate filter regeneration, a potential torque increase is transmitted through multiple torque paths of the transmission to maintain output torque relatively constant.

Abstract: A procedure for the control and regulation of a clutch of an automatic stepless transmission for a motor vehicle in which an electronic control device, via a first or second regulation circuit, determines the behavior of the clutch during three driving conditions and wherein a stepless gear ratio change is carried out from a first into a second gear ratio. In accord with the invention, for the control and the regulation of the clutch during the first driving condition, the first regulation circuit is employed, the size of the regulation thereof being equivalent to the actual value of the motor speed of rotation (n_MOT_IST). During the second driving condition, a second regulating circuit is employed, the size of the regulation thereof being equivalent to the actual value of a difference in speeds of rotation (dnK_IST) of the clutch and during the third driving condition, the clutch is subjected to a controlled pressure value dependent upon various value influences.

Abstract: In order to more precisely calculate a fill time of a friction element of an automatic transmission that is either engaged or disengaged during shifting between an N-range, a D-range, and an R-range, this invention compensates a piston stroke ratio by detecting an N-range hold time and by using the N-range hold time and a pre-installed map when a shift signal indicating shifting into one of the D-and R-ranges from an N-range is detected, compensates the piston stroke ratio by detecting a D/R-range hold time and by using the D/R-range hold time and the pre-installed map when a shift signal indicating shifting into the N-range from one of the D- and R-ranges is detected, and calculates a fill time using the compensated piston stroke ratio.

Abstract: The present invention discloses a preferred method for operating a adaptive clutch system of the type used in a motor vehicle power transfer assembly by employing a dithered control signal. One aspect of the present invention superimposes a dithering signal onto a control signal by nulling consecutive blocks of control signal pulses. Another aspect of the present invention provides a method for generating a dithered control signal by providing a wave function with which to systematically vary a duty cycle of the dithered control signal. A method for varying the output force of a clutch actuator assembly in response to the dithered control signal is also provided.

Abstract: A torque converter (1) comprises a pump impeller (1a) and turbine runner (1b) which transmit a torque via a fluid, and a lockup clutch (2) which engage the pump impeller (1a) and turbine runner (1b) according to an oil pressure. The pump impeller (1a) is connected to an engine (21), and the turbine runner (1b) is connected to an automatic transmission (23). An oil pressure control valve (3) supplies oil pressure to the lockup clutch (2) according to a signal from the controller (5). The controller (5) calculates a rotation speed increase rate of the turbine runner (1b) (S1), and controls the oil pressure of the oil pressure control valve (3) under a pressure increase rate which increases as the rotation speed increase rate (S10) increases, thereby preventing rotation speed fluctuations of the engine (23) accompanying lockup of the lockup clutch (2).

Abstract: A center differential limiting control unit calculates and sets a vehicle speed, a target difference in a rotational speed between front and rear axle shafts, a control start difference in the rotational speed, and an actual difference in the rotational speed, respectively. Then, when the actual difference is large than the control start difference, it is determined that a front and rear axle shaft control start condition is established, and front and rear axle shaft differential limiting torque is calculated according to the actual difference and the target difference. In contrast, when the actual difference is smaller than the control start difference, it is determined that the front and rear axle shaft control start condition is not established, and an integral term in the front and rear axle shaft limiting torque and control is set to 0.

Abstract: In a power distribution control system for a four-wheel-drive vehicle, a 4WD controller is electronically connected to a friction clutch for controlling a torque distribution ratio. The 4WD controller determines whether a past-history condition that a clutch input torque has been greater than or equal to a predetermined threshold value is satisfied when a command torque is greater than or equal to the predetermined threshold value, and determines whether a command torque condition that a current command torque is greater than or equal to the predetermined threshold value is satisfied, and also determines whether a reversal-of-torque condition that an input direction of torque inputted into the friction clutch is reversed is satisfied. The 4WD controller outputs a countermeasure-of-noise command torque decreased from the current command torque as a command signal for the friction clutch, when the past-history condition, the command torque condition, and the reversal-of-torque condition are all satisfied.

Abstract: A differential limiting control apparatus for a vehicle has: clutch unit interposed between one rotational shaft and the other rotational shaft for variably transmitting a driving force between the one rotational shaft and the other rotational shaft; target differential speed setting unit for setting a target differential speed between the one rotational shaft and the other rotational shaft, actual differential speed detecting unit for detecting an actual differential speed between the one rotational shaft and the other rotational shaft, and clutch torque computing unit for computing an engagement force of the clutch unit by obtaining a deviation between the target differential speed and the actual differential speed, configuring a switching function by using at least a polarity related to an integral term of the deviation, and applying a sliding mode control.