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.

Abstract: The invention relates to a drive train having a twin-clutch transmission and to a method for controlling the same.

Abstract: The invention concerns a method for controlling automatic or automated transmission downshift used for power braking and comprising set of predetermined shifting laws, characterized in that it consists, below a certain arbitrary threshold Ethreshold of the accelerator pedal depression, in defining a new downshift law designed to be substituted for the current standard downshift law.

Abstract: A transmission comprises a first transmission mechanism and a second transmission mechanism. When a clutch is in an engaged state, the first transmission mechanism transmits a driving force from the engine to the axle shaft. When a clutch is in a disengaged state, the second transmission mechanism transmits a driving force from the engine to the axle shaft. An electromagnetic brake is connected to the second transmission mechanism. A braking force generated by the electromagnetic brake allows the transmission of a driving force by the second transmission mechanism. Thus, a driving force is continuously provided even when the clutch is released for a gear change operation.

Abstract: A transmission having plural clutches includes a first clutch for connecting and disconnecting transmission of driving force to a first input shaft including a driving gear configured to be engaged with a driven gear provided at an output shaft of the transmission driven by a driving force generating device, a second clutch operating independently from the first clutch for connecting and disconnecting transmission of driving force to a second input shaft including a driving gear configured to be engaged with a driven gear provided at the output shaft, a driving force detection device for detecting driving force, a slip detection device for detecting physical quantity related to a slip of a driving wheel, and a device for controlling the second clutch for importing the physical quantity related to the slip and the driving force and for controlling engagement ratio of the second clutch where the first clutch is engaged.

Abstract: Clutch pressure is reduced to an initial pressure, and a transmission operation state is stored, when a vehicle is stopped with an engine in an idling state. The clutch pressure is further reduced at a constant change rate and the amount of time is measured until the turbine rotation speed increases to the predetermined rotation speed. Based on the measured amount of time, a correction amount is computed for the initial pressure necessary to increase the turbine rotation speed to the predetermined rotation speed in a predetermined amount of time. The correction amount is stored in a memory region corresponding to the transmission operation state when the clutch pressure is reduced to the initial pressure. The initial pressure is corrected according to the correction amount stored in the memory region corresponding to the transmission operation state when the clutch. pressure is reduced.

Abstract: In automatic shift control apparatus and method for a manual transmission, at least one clutch is interposed between an engine and the manual transmission and a controller performs a feedback control for an engagement force of the clutch after a gear shift for the manual transmission is ended in such a manner that an input revolution speed of the clutch is directed toward another revolution speed thereof after the gear shift occurs at a predetermined time variation rate, the controller setting mutually different feedback control gains in a variation region of the input revolution speed of the clutch in which the input revolution speed of the clutch is directed toward the other revolution speed after the gear shift occurs and in a convergence region of the input revolution speed in which the input revolution speed of the clutch has reached to the other revolution speed after the gear shift occurs.

Abstract: In an automatic transmission including a forward clutch and a lockup clutch of a torque converter which are provided on a driving-power transmitting path between an engine and a driving wheel, a vehicle driving condition is classified into a plurality of regions and an associated slip control between the forward clutch and the lockup clutch is executed. Accordingly, both of improvements of gas mileage and drivability can be attained at a high level.

Abstract: A method for detecting tie-up in an automatic transmission is provided. The rate of change of the output shaft acceleration is calculated by twice differentiating with respect to time the transmission output shaft speed. The calculated rate is then compared to a predetermined value, and each time the acceleration rate drops below the predetermined value, a controller stores the event in memory. If the acceleration rate drops below the predetermined value too frequently, a flag is set and indication of the transmission tie-up is prevented. When a predetermined amount of time passes, during which the acceleration rate does not drop below the predetermined value, the flag is cleared and indication of a tie-up is allowed. When the acceleration rate drops below the predetermined value, and the transmission is in a shift cycle and tie-up prevention flags are cleared, a transmission tie-up is indicated.

Abstract: A control device for a drive line of a vehicle, in which a drive line from a power source to drive wheel includes a wheel control for controlling the speed of the wheels, and a connection mechanism for increasing/decreasing a torque transmission capacity between the power source and the drive wheels. The control device includes a trouble detector for detecting that the wheel control is in a situation unable to control the speed of the wheels normally. A braking detector detects that a braking operation to brake the rotation of the wheels is executed. And, a torque interruption control reduces the torque transmission capacity by the connection mechanism, when it is detected by the trouble detector that the wheel control cannot control the speed of the wheels normally and when it is detected by the braking detector that the braking operation to brake the rotation of the wheels is executed.

Abstract: A shift control system for an automatic transmission wherein shifting from a first gear ratio to a second gear ratio is carried out by releasing the hydraulic pressure of a first friction engaging element for disengagement thereof and supplying the hydraulic pressure to a second friction engaging element for engagement thereof, the hydraulic pressure to the second friction engaging element being subjected to feedback control, wherein the shift control system includes a sensor for sensing a parameter on a vehicle cruising condition; and an ECU having a part for calculating, in accordance with the sensed parameter, a difference in output-side rotational speed of the fluid coupling before and after the shifting; and a part for setting, when the shifting is carried out with an output of the engine being smaller than a predetermined value, the second hydraulic pressure in accordance with the calculated difference immediately before start of the feedback control.

Abstract: A clutch is operated by an actuating pressure pressure during an engaging process of the clutch. The actuating pressure is controlled over time such that predetermined characteristics for an engagement of said clutch are approximated by starting a process for changing a rotational speed of an output shaft of the torque converter for an adaptation of the rotational speed to an actual velocity of the vehicle during engagement of the clutch. An ideal signal for the rotational speed is determined which corresponds to an estimate for an engagement of the clutch with the predetermined characteristics. An actual signal of the rotational speed of the output shaft over time is measured during said process. Deviations are determined between the actual signal and the ideal signal. Finally the signal of the actuating pressure over time is automatically changed in order to reduce the deviations between the actual signal and the ideal signal if the deviations exceed a threshold.

Abstract: A control device for a vehicle which has a function to reduce the change-speed shock when changing the speed by controlling the transmission of the vehicle. The control device performs the switching between a manual change-speed mode in which the vehicle speed can be changed based on a change-speed command generated by manual operation and an automatic change-speed mode in which a transmission gear ratio can be controlled based on the predetermined change-speed characteristic. Thereby the reduction amount of the change-speed shock can be changed between the manual change-speed mode and the automatic change-speed mode.

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: The invention relates to a motor vehicle comprising a drive motor and a gearbox with a device for automatically actuating a clutch in the drivetrain, and to a control method. According to said method, if the gear ratio is less than a threshold value and the actuation of a driving pedal is not equal to zero and is less than a threshold value, warning measures are initiated to alert the driver to misuse.

Abstract: A multistage automatic transmission comprises first and second clutches and a throttle open degree sensor. The first and second clutches are arranged to establish odd and even speeds of the transmission when engaged. A control unit of the transmission is configured to carry out determining a desired speed of the transmission upon receiving information signals; causing at least one the first and second clutches to be engaged to establish the desired speed; and applying a limitation to an engaging force produced by at least one of the first and second clutches when the throttle open degree sensor senses that the open degree of a throttle valve is smaller than a predetermined degree.

Abstract: A method for controlling a damper clutch release control system which performs duty control in releasing a damper clutch for down-shifting in a sports mode decreasing gear-shift shock, is provided. The method requires determining whether a down-shift signal is inputted in a state when a gear shift mode is a sports mode and a throttle valve opening angle is within a predetermined range, and performing duty control until a transmission control outputs a down-shift start signal to a transmission when it is determined that the down-shift signal is inputted.

Abstract: A drive-force distribution controller for a four-wheel-drive vehicle in which drive force produced by an engine is transmitted directly to front or rear wheels and is transmitted to the remaining wheels via a torque distribution clutch, and the engagement force of the torque distribution clutch is controlled in accordance with traveling conditions of the vehicle. The controller includes a calculation unit for calculating variation per unit time in rotational speed difference between the front wheels and the rear wheels; and a control unit for controlling the engagement force such that the engagement force increases as the variation per unit time in the rotational speed difference increases.

Abstract: The power train of a motor vehicle employs an electronic control unit which selects the extent of engagement of the friction clutch between the engine and the transmission by way of an electronic or fluid-operated actuator. The throttle valve for the engine is adjustable by the control unit and/or by the accelerator pedal to ensure predictable starting of the motor vehicle from standstill on a road surface having a pronounced slope and/or when the motor vehicle carries a heavy load.

Abstract: The invention relates to a method of compensating for the influence of changes of speed of a rotary component of an adjustable clutch upon the control torque characteristic curve of the clutch in the power train of a motor vehicle wherein the clutch operates between the rotary output element of the engine or another prime mover and a rotary input element of a change-speed transmission. The method includes the steps of monitoring the rotational speed of the clutch and varying the required positions of a mobile adjusting member for the clutch as a function of changes of the monitored rotational speed. The invention also relates to the power train wherein the influence of changes of rotational speed of the aforesaid component upon the characteristic curve can be varied in accordance with the novel method.

Abstract: A sensor mounting mechanism for a clutch case is provided, which can not only prevent temperature rise of a sensor but also simplify mounting of the sensor on the clutch case. The sensor mounting mechanism is for a clutch case which houses a clutch and a detection object (a pulse gear) rotating with the clutch in unison. A sensor for detecting a rotation of the detection object is inserted through a hole made on the clutch case with a thermal insulator (spacer) and a detector of the sensor is oriented opposite to the detection object.

Abstract: A transmission system for a straddle vehicle which provides two operating modes, namely semi-automatic and automatic. With the semi-automatic transmission system, an operator only uses a switching means mounted on a sheeting bar of the vehicle for activating a clutch actuator and a shift actuator. The clutch actuator disengages a transmission clutch while the shift actuator operates a shifter for changing the transmission ratio. With the automatic transmission system, an Electronic Control Unit reads inputs signals such as speed of the engine (RPM), speed of the vehicle, opening of a throttle valve and position of a shifter and accomplishes a smooth shifting by activating a clutch actuator, a shift actuator and a modulated controlling valve.

Abstract: In a transmission which transmits a power from an electrical motor 1 to a countershaft 30 with a speed change, a drive side rotating member which is coupled to a main shaft 10 experiences a rotational change along with the main shaft 10 when a shift from a first speed ratio to a second speed ratio is executed, and an intermediate rotating member experiences a rotational change in a direction opposite to that of the drive side rotating member when the shift is executed. In this transmission, the ratio of the rotational inertia of the drive side rotating member to the rotational inertia of the intermediate rotating member equals the reciprocal of the ratio of the rotational change of the drive source to the rotational change of the intermediate rotating member, the rotational changes being experienced during the shift.

Abstract: An apparatus for controlling a power transmission device, having a lockup shift valve that changes the operating state and non-operating state of the lockup mechanism, and a regulator valve that is capable of changing the pressure (line pressure) of working oil used to operate a speed changer CVT between a low pressure and a high pressure, wherein changeover between a mode, where the lockup mechanism is operated and the line pressure is set to a low pressure, and a mode, where the lockup mechanism is not operated and the line pressure is set to a high pressure, is carried out by changing the output of ON and OFF signals from the first solenoid valve.

Abstract: To make it possible to maintain speeds during failures in an automatic transmission that does not have exclusive friction elements corresponding to the attainment of each speed. The hydraulic control apparatus of an automatic transmission, provided with control means 71-74 for supplying regulated pressure to each of the hydraulic servos 81-84 that are first through fourth friction elements to which hydraulic pressure is supplied from the oil path L1, and provided with switching valves (1)-(5) for cutting off the supply of hydraulic pressure to friction elements other than the friction elements that engage in each speed, on the upstream side of the supply paths L31, L32, L10, L11 and L12. Each switching valve is switched by hydraulic pressure (C1-C3, B1 pressures) regulated by the control means that achieve regulated pressure operating conditions during failures, and selective application of signal pressure (Sol, SolB, SoIC pressures) output by the control means as operating means.

Abstract: A control unit controls a lockup duty ratio to be maintained at a first duty ratio, which is the minimum value within such a range as not to slip a lockup clutch, during a period of time since a decision is made to perform a shifting operation until an actual shifting operation is started. The control unit then lowers the lockup duty ratio to a corrected (learned) second duty ratio and gradually lowers the lockup duty ratio from the second duty ratio at a predetermined rate of change so that a slip revolutionary speed can be equal to a target slip revolutionary speed when the shifting operation is finished. Alternatively, the control unit corrects the rate of change while maintaining the second duty ratio at a uniform value so that the slip revolutionary speed can be equal to the target slip revolutionary speed when the shifting operation is finished.

Abstract: A synchronous meshing type automatic transmission control system is provided to be capable of shortening a time for gear change without generation of noises from gears and degradation of a synchronizing mechanism in durability, and comprises an internal combustion engine mounted on a vehicle, a speed change mechanism coupled to the internal combustion engine through a clutch, a shift-select actuator for selectively coupling one set of a plurality of sets of speed change gears having different gear ratios and intervening between an input shaft coupled to the clutch of the speed change mechanism and an output shaft for driving the vehicle, and a control device for inputting thereinto an output signal of a shift-select position sensor, which detects a selected position of the shift-select actuator, to operate a position of the shift-select actuator for gear change and for putting the clutch in weak coupling in a state, in which no gear is coupled between the input shaft and the output shaft in the course of gear

Abstract: A gear-mesh type automatic transmission system capable of controlling clutch coupling speed so as to mitigate shock likely to occur upon changeover of speed stage regardless of not only time-dependent deterioration of an electromagnetic clutch but also dispersion among individual clutches. The gear-mesh type automatic transmission system includes an electromagnetic clutch (2) for effectuating transmission and interruption of output power from an output shaft (21) of an engine (1) to an input shaft (22) of a gear-mesh type transmission (3), a shift/select actuator (5) for shifting a speed change gear to a shift/select position in the gear-mesh type transmission (3), a shift/select position sensor (6) for detecting a shift/select position of the speed change gear, and a control unit (4) for driving the shift/select actuator (5) in accordance with a shift lever position selected by a driver, to thereby change over automatically the gear-mesh type transmission (3) to a target speed stage.

Abstract: A control device for controlling a clutch of a vehicle wherein an actuator is connected to and provides for operating the clutch, the work position of which is determined by a position sensor which supplies a measured position signal to a control device receiving an information signal and supplying a control signal for the actuator; the control device has a monitor circuit for determining malfunctioning of the position sensor and supplying a fault signal; and a virtual sensor device for estimating the work position of the clutch to supply the control device, in the presence of the fault signal, with a virtual position signal instead of the measured position signal.

Abstract: A shift control apparatus and a shift control method for the automatic transmission, which can reduce the required value of the drive force for the shift actuator, to make the automatic transmission cheaper and to improve install character thereof. The shift control apparatus includes a transmission 2, a clutch 3, a first drive means 4, 6 for operating the clutch, a second drive means 5 and 6 for operating a synchro mechanism, a third drive means 6 and 31 for varying the number of rotation of an engine, and a control unit 30 for controlling the first, second and third drive means. The control unit 30 has a clutch control portion 18 to control the first drive means, a synchro control portion 19 to drive the second drive means the engine, and an engine control portion 20 to control the third drive means.

Abstract: A synchronous meshing type automatic transmission control system is provided to be capable of shortening a time for gear change without generation of noises from gears and degradation of a synchronizing mechanism in durability, and comprises an internal combustion engine mounted on a vehicle, a speed change mechanism coupled to the internal combustion engine through a clutch, a shift-select actuator for selectively coupling one set of a plurality of sets of speed change gears having different gear ratios and intervening between an input shaft coupled to the clutch of the speed change mechanism and an output shaft for driving the vehicle, and a control device for inputting thereinto an output signal of a shift-select position sensor, which detects a selected position of the shift-select actuator, to operate a position of the shift-select actuator for gear change and for putting the clutch in weak coupling in a state, in which no gear is coupled between the input shaft and the output shaft in the course of gear

Abstract: A control for shifting into a start ratio in a computer-assisted (48) vehicular splitter-type compound transmission (16) having a main section (16A) shifted by a manually operated shift lever (31) and a controller (42). The splitter section (16E) is provided with a three-position (L, H, N) actuator (46) and is commanded to a splitter-neutral position upon sensing a main section shift to neutral, master clutch (14) disengagement and low vehicle speed (OS<REF<3 MPH) to reduce the inertia of the main shaft assembly and reduce the need for a clutch brake when engaging a start ratio.

Abstract: A gear-mesh type automatic transmission system capable of controlling clutch coupling speed so as to mitigate shock likely to occur upon changeover of speed stage regardless of not only time-dependent deterioration of an electromagnetic clutch but also dispersion among individual clutches. The gear-mesh type automatic transmission system includes an electromagnetic clutch (2) for effectuating transmission and interruption of output power from an output shaft (21) of an engine (1) to an input shaft (22) of a gear-mesh type transmission (3), a shift/select actuator (5) for shifting a speed change gear to a shift/select position in the gear-mesh type transmission (3), a shift/select position sensor (6) for detecting a shift/select position of the speed change gear, and a control unit (4) for driving the shift/select actuator (5) in accordance with a shift lever position selected by a driver, to thereby change over automatically the gear-mesh type transmission (3) to a target speed stage.

Abstract: A device and a method of controlling a progressive change of an overall transmission ratio from an old transmission ratio to a new transmission ratio are described. The method is applicable in a transmission device comprising a first and a second gear trains which are independently shiftable for determining together an overall transmission ratio of the transmission device. The method includes detecting a physical magnitude which is influenced by progressive ratio change in the second gear train, resulting in a progressive variation of said overall transmission ratio in one direction, and also includes controlling an actuator of a first selective coupling means as a function of a detected value of the physical magnitude to progressively change a transmission ratio in the first gear train in a direction contrary to the first direction.

Abstract: A pressure control apparatus and method are provided for controlling hydraulic clutches of a backward and forward drive switching device mounted in a transmission of a working vehicle such as a tractor. When a backward and forward drive switching shuttle lever is operated, a current supplied to an electromagnetic proportional valve is controlled to gradually increase the pressure for a hydraulic clutch corresponding to a direction of movement. When a propelling drive connecting and disconnecting clutch pedal is operated, the pressure for that hydraulic clutch is controlled through the electromagnetic proportion valve, based on a depressed position of the pedal. When the operator switches the shuttle lever from forward to backward or vice versa, a microcomputer causes the shuttle control current to rise at a point of time of start of a clutch engaging operation of the clutch pedal.

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 transmission system for a straddle vehicle which provides two operating modes, namely semi-automatic and automatic. With the semi-automatic transmission system, an operator only uses a switching means mounted on a sheeting bar of the vehicle for activating a clutch actuator and a shift actuator. The clutch actuator disengages a transmission clutch while the shift actuator operates a shifter for changing the transmission ratio. With the automatic transmission system, an Electronic Control Unit reads inputs signals such as speed of the engine (RPM), speed of the vehicle, opening of a throttle valve and position of a shifter and accomplishes a smooth shifting by activating a clutch actuator, a shift actuator and a modulated controlling valve.

Abstract: A transmission control apparatus is used with a vehicle having an internal combustion engine, a transmission connected to the engine and having a plurality of gear positions, and a generator which is disposed between the transmission and drive wheels and which is capable of generating electric power through regenerative braking during deceleration of the vehicle. The control apparatus operates to detect a revolution speed of the internal combustion engine, and to place the transmission in a highest gear position selected from one or more gear positions that enable the engine revolution speed to be maintained at a level not lower than a predetermined lower limit above which the engine can operate by itself (i.e., re-start), when the generator generates electric power through regenerative braking.

Abstract: A speed-change pattern switching control system for an automatic transmission of a motor vehicle which can ensure enhanced comfort when driving the motor vehicle. The system decides the running state of the motor vehicle on the basis of driving/operation information (Te, Tm, T&agr;, &agr;f, &agr;s), performs a first filter processing on the running state information and the driving/operation information (Vs, &thgr;, &agr;f, Ws, Ps), stores the manipulated information (Jm) for the motor vehicle in the manual speed change mode, performs a second filter processing on the manipulation information (Jm) in the manual speed change mode, outputs of the running state and the driving/operation information, and corrects speed-change patterns for the automatic transmission on the basis of output signals of the first and second filter processing.

Abstract: A control apparatus for an automatic transmission of a vehicle having a forward friction element for engaging or disengaging a turbine shaft with the automatic transmission in a forward running direction and a lock-up clutch for directly transmitting a rotation of an engine to the turbine shaft, comprises an abrupt deceleration control means for disengaging the forward engagement element and the lock-up clutch when an abrupt deceleration of the vehicle is detected, and a restoring means for canceling the abrupt deceleration control means and for restoring the forward friction element to an engagement state when an accelerator pedal is depressed for acceleration.

Abstract: A shift by wire vehicle transmission includes control methods for engaging gears after the vehicle has been at rest or coasting. When the vehicle is started from a stop or rest, a default starting gear is automatically selected. The driver can override the default gear and choose to start driving the vehicle in one gear above or below the default starting gear by manipulating a shift lever. Similarly, the driver can override the default starting gear to begin driving the vehicle in reverse. When the vehicle has been coasting, the transmission control unit chooses the next gear based upon a signal that is provided when the driver manipulates the shift lever. Depending on the indicated desire of the driver, the system controller automatically selects a gear depending upon vehicle speed and torque conditions.

Abstract: An electric-power-assist transmission and a shaft control method which allow good operability to be obtained. A main clutch is put in an engaged or disengaged state in a manner which is mechanically coupled with the rotation of a shift spindle. At normal times, the rotational direction and the rotational speed of the shift spindle rotated by a driving motor are controlled in accordance with a first control procedure. However, with the main clutch in a disengaged state, as the rotational speed of the engine exhibits a predicted change, the rotational direction and the rotational speed of the shift spindle are controlled in accordance with a second control procedure which is different from the first control procedure.

Abstract: The invention related to a method for engaging power take-offs (28) in automated or partially automated transmissions (6) of commercial vehicles. A signal from the driver corresponding to a wish to engage the power take-off (28) is converted in a control device (34) into a signal for opening an automated clutch (4) between a prime mover (2) and the transmission (6) of the commercial vehicle. Once a predetermined minimum number of revolutions of the input shaft (10) of the transmission (6) is reached, a shifting device (26) is controlled for connecting the power take-off (28) with one transmission shaft (16, 42) that drives the power take-off (28) in order to obtain a closing of said shifting device (26, 52). The clutch (4) is again closed to prevent the teeth (50, 53) of the shifting device (26, 52) from remaining in front of each other.

Abstract: In an engine provided with a throttle valve actuator which controls the opening/closing of the throttle valve, a target throttle valve opening degree is determined based the amount of accelerator pedal depression. Following a speed change command being issued in an automatic transmission the target throttle position is gradually decreased until an inertial phase is detected. The target throttle opening is then returned to that which corresponds to the accelerator pedal depression by the driver.

Abstract: A control apparatus for an automatic transmission of twin clutch type, in which a skip downshift is executed with a light gearshift shock and in a short gearshifting time period. As illustrated in FIG. 1, after the release of a clutch C2, a command for switching over a synchro mechanism is issued at a time t3. When the r.p.m. NT of a turbine has reached the synchronous r.p.m. NT3 of the intermediate stage of the skip downshift, the oil pressure of a clutch C1 is raised in order that the rising rate of the turbine r.p.m. (speed) NT may become a predetermined value d/dt(NT1) or d/dt(NT2). Thereafter, the oil pressure of the clutch C1 is controlled in order that the turbine r.p.m. NT may maintain a value NT2 (synchronous r.p.m. of the lower speed stage of the skip downshift)+.DELTA.NT4. After the completion of the switchover of the synchro mechanism, the oil pressure of the clutch C2 is gradually raised, and that of the clutch C1 is gradually lowered. Thus, the skip downshift in a power-ON state is executed.

Abstract: A powertrain system for a hybrid vehicle. The hybrid vehicle includes a heat engine, such as a diesel engine, and an electric machine, which operates as both an electric motor and an alternator, to power the vehicle. The hybrid vehicle also includes a manual-style transmission configured to operate as an automatic transmission from the perspective of the driver. The engine and the electric machine drive an input shaft which in turn drives an output shaft of the transmission. In addition to driving the transmission, the electric machine regulates the speed of the input shaft in order to synchronize the input shaft during either an upshift or downshift of the transmission by either decreasing or increasing the speed of the input shaft. When decreasing the speed of the input shaft, the electric motor functions as an alternator to produce electrical energy which may be stored by a storage device.

Abstract: In an automatic transmission of the type wherein a stage intermediate between a higher speed stage and a lower speed stage is achieved through a clutch-to-clutch operation, a power-ON skip downshift is executed via the intermediate stage. First, when the skip downshift has been judged, the hydraulic pressure of the clutch (C4) of the higher speed stage is lowered. Next, when the input speed(r.p.m.) of the transmission have reached the synchronous r.p.m. (SS3) of the intermediate stage, the hydraulic pressure (P3) of the clutch (C3) of the intermediate stage is raised and adjusted so that the rise rate of the input r.p.m. may become a specific value d/dt(NT1). When the input r.p.m. have exceeded the synchronous r.p.m. (SS2) of the lower speed stage, the hydraulic pressure of the intermediate-stage clutch (C3) is adjusted so that the input r.p.m. may keep specific r.p.m. higher than the synchronous r.p.m.

Abstract: A control system for a starting clutch installed in an automotive vehicle. The starting clutch is arranged between the engine and at least one wheel of the vehicle, for controlling engagement between the engine and the at least one wheel. A basic torque capacity of the starting clutch is calculated based on the rotational speed of the engine, and a torque capacity correction value is determined such that it assumes a minimal value when a clutch speed ratio of the starting clutch detected by a clutch speed ratio sensor is equal to 1.0 and progressively increases as the clutch speed ratio increases and decreases from 1.0. The determined torque capacity correction value is changed based on the throttle valve opening, and the torque capacity of the starting clutch is determined based on the changed torque capacity correction value and the calculated basic torque capacity.

Abstract: Broadly, the present invention is directed to a method for controlling the shifting of a drag race vehicle with a controller for controlling an actuatable shifter assembly. This method includes resetting the controller followed by actuating the controller and launching the vehicle. At a predetermined engine speed value or after a first timed duration based on a predetermined engine speed value, the shifter assembly is actuated for a second timed duration to shift to a next higher gear. Finally, shifter assembly actuation is repeated until all of the gears of the vehicle desired to be shifted have been shifted. Another aspect of the present invention is a controller for controlling the shifting of a drag race vehicle shifter with an actuatable shifter assembly and which is activatable by a first duration timer or an rpm switch based on a predetermined engine speed value.

Abstract: A shift control system for an automatic is designed to prevent engine racing and clutch tie-up during a clutch-to-clutch shift (clutch switching shift) involving engagement/disengagement of first and second frictional engagement elements. The shift control system includes an engagement force controller for independently controlling both of the frictional engagement elements. A gear ratio calculator continuously calculates a gear ratio r of the transmission and a shift characteristic value calculator calculates a shift characteristic value .alpha. based on changes in the gear ratio between the start of the shift and completion of the shift. A control value calculator calculates a control value .beta., based on the shift characteristic value .alpha. calculated by the shift characteristic value calculator and a shift characteristic value .alpha.I on an ideal gear ratio curve. The control value .beta. is calculated so that the shift characteristic value .alpha. coincides with the shift characteristic value .