Abstract: A coast stop vehicle includes a variator which continuously changes a speed ratio by changing a winding diameter of a belt mounted on pulleys, a sub-transmission mechanism connected in series with the variator and shifting discrete gear positions by changing engaged states of a plurality of frictional engagement elements, and a coast stop unit which stops the rotation of the drive power source and releases the engaged frictional engagement element when the coast stop condition holds during travel. The coast stop unit includes a coast stop prohibiting unit which prohibits the coast stop regardless of the coast stop condition when it is predicted at the time of determining whether or not the coast stop condition holds that a belt tightening force of the pulley falls below an engaging force of the frictional engagement element in the engaged state by the execution of the coast stop.

Abstract: A coast stop vehicle which stops an engine during the travel of the vehicle is provided with a variator including a pair of pulleys and a belt mounted between the pulleys and capable of continuously changing a speed ratio. A controller judges whether or not coast stop conditions to stop the engine during the travel of the vehicle hold, stops the engine when the coast stop conditions hold, and prevents the speed ratio from being upshifted to a higher side than a speed ratio at the time of starting the coast stop control during the coast stop control.

Abstract: A method for controlling a powertrain for an automotive vehicle includes determining a desired flywheel torque, determining, with reference to the desired flywheel torque, a desired torque capacity torque of a clutch through which torque is transmitted between the flywheel and wheels of the vehicle, operating the clutch to produce the desired clutch torque capacity, determining a slip error across the clutch, and changing a gear ratio of a continuously variable transmission located in a drive path between the clutch and said wheels to a gear ratio that reduces the slip error.

Abstract: A simplified continuously variable transmission system control provides a variable clamping force and a differential cylinder pressure manipulation to change sheave ratios. The system control uses two pumps. The first pump provides the variable clamping force. The second pump provides pressure changes to effect ratio changes. The clamping force can be varied based upon operator demand on an associated engine.

Abstract: The invention provides for a vehicle drive line provided with an engine (1) capable of generating an engine torque (Te), a continuously variable transmission (2), a driven wheel (5) and two friction clutches (3, 33), a first clutch (3) being positioned in the drive line between the engine (1) and the transmission (2) and a second clutch (33) being positioned between the transmission (2) and the driven wheel (5), wherein a torque (Tc-max) that is transmissible by the first clutch (3) and a torque (Tc-max) that is transmissible by the second clutch (33) are both less than a torque (Tt-max) transmissible by the transmission (2) and, at the same time, are both essentially equal to or slightly higher than the engine torque (Te).

Abstract: In a hybrid vehicle provided with a power dividing mechanism comprising a clutch mechanism, an ECU performs speed-change control. In the control, the ECU performs an engage preparing process if it is necessary to engage clutch plates of the clutch mechanism with each other. In the process, the ECU switches a reference value which is referred in a feedback control for performing a rotation synchronization and a position synchronization for the clutch plates from a calculated value which is calculated from a pulse signal of first rotational sensor mounted the clutch plate to an estimated value which is estimated from a pulse signal of each of second and third rotational sensors for detecting rotational speed of each motor generators if clutch rotational speed as rotational speed corresponding to the clutch plate as an engagement element decreases to less than a criterion value.

Abstract: A drive force control system includes a shifting demand judging means that judges whether or not a torque capacity of the clutch is relatively high, and a condition for changing the speed change ratio of the continuously variable transmission stepwise is satisfied; and a first shifting means, that reduces the torque capacity of the clutch before changing the speed change ratio of the continuously variable transmission, to synchronize a rotational speed of the internal combustion engine with an input speed of the continuously variable transmission to be attained after changing the speed change ratio thereof while changing the speed change ratio of the continuously variable transmission, and to increase the torque capacity of the clutch after changing the speed change ratio of the continuously variable transmission, when changing the speed change ratio of the continuously variable transmission stepwise.

Abstract: A continuously variable transmission for a motorcycle that provides appropriate engagement of a centrifugal clutch when a clutch shoe is worn. A control unit controls a change gear ratio to a TOP side to engage the centrifugal clutch when the centrifugal clutch is disengaged and an engine rotational speed is higher than a predetermined first rotational speed.

Abstract: A work machine includes an internal combustion (IC) engine, and an infinitely variable transmission (IVT) coupled with the IC engine. The IVT includes an adjustable module and a mechanical module, with an adjustable input/output (I/O) ratio. A clutch is coupled with the mechanical module and has an output. An adjustable operator input device provides an output signal representing a power limit control. At least one electrical processing circuit is coupled with the operator input device and configured for controlling a selected combination of the I/O ratio and the clutch output, dependent upon the output signal from the operator input device.

Abstract: A transmission mechanism including a switching clutch or brake that is switchable between a continuously-variable shifting state and a step-variable shifting state, and has both an advantage of improved fuel economy provided by a transmission, the speed ratio of which is electrically variable, and an advantage of high power transmitting efficiency provided by a gear type power transmitting device constructed for mechanical transmission of power. While a clutch-to-clutch shifting action of an automatic transmission portion is in a tie-up state, a differential portion is placed in a continuously-variable shifting state by switching control, and engine speed is changed under the control of hybrid control, so as to prevent a drop of the engine speed for thereby reducing a shock of the shifting action, unlike in a non-continuously-variable shifting state of the differential portion in which the engine speed is directly influenced by the tie-up state.

Abstract: A torque distribution system is provided for a vehicle that uses a planetary gear set, an electric motor, and a torque-transmitting mechanism to control a torque difference between two axially-aligned wheels on a vehicle. The torque distribution system includes a planetary gear set having a first, a second, and a third member. The torque-transmitting mechanism is selectively engagable to connect the first and second members of the planetary gear set for common rotation. The second and third members of the planetary gear set are continuously operatively connected with the first and second rotatable connecting elements, respectively. The motor is continuously connected with the first member of the planetary gear set such that the motor adds or subtracts torque to the first member when the motor is energized and also adds or subtracts torque to the second member when the motor is energized and the torque-transmitting mechanism is engaged.

Abstract: A method controlling a clutch arrangement that serves, in a powertrain of a motor vehicle, for the transmission of a torque from an input element to an output element. Starting from an activated state of the clutch arrangement, a respective estimated torque value is calculated in repeating calculation cycles. A torque build-up value is calculated in dependence on at least one speed difference value. A torque reduction value is calculated in dependence on at least the last calculated estimated torque value. The estimated torque value is re-calculated on the basis of the last calculated estimated torque value by up integration of the calculated torque build-up value and down integration of the calculated torque reduction value. The recalculated estimated torque value is compared with a torque threshold value. The clutch arrangement is deactivated when the recalculated estimated torque value is below the torque threshold value.

Abstract: A method for controlling a powertrain for an automotive vehicle includes determining a desired flywheel torque, determining, with reference to the desired flywheel torque, a desired torque capacity torque of a clutch through which torque is transmitted between the flywheel and wheels of the vehicle, operating the clutch to produce the desired clutch torque capacity, determining a slip error across the clutch, and changing a gear ratio of a continuously variable transmission located in a drive path between the clutch and said wheels to a gear ratio that reduces the slip error.

Abstract: To prevent engine speed from increasing during low-speed operation, a transmission includes a change-gear mechanism, a centrifugal clutch, a control unit and a secondary sheave rotation sensor. The change-gear mechanism has an input shaft, an output shaft and an actuator for changing a change-gear ratio between the input and output shafts. The centrifugal clutch is connected to the output shaft. The control unit controls the actuator. The secondary sheave rotation sensor detects and outputs a rotational speed of the output shaft to the control unit. The control unit controls the actuator based on a target change-gear ratio obtained by dividing a target rotational speed of the input shaft by the rotational speed of the output shaft.

Abstract: With a two-shaft engine, the accessory drive gearbox (5) for the operation of a generator and other auxiliaries (6) is connected to the high-pressure shaft (1) via a high-pressure shaft gearbox (3), which is coupled to a low-pressure shaft gearbox (8) connecting to the low-pressure shaft (7), via an overrunning clutch (11), a conical-pulley variable transmission (10) settable on the basis of the shaft speed on both sides, and a first switchable clutch (9). Under certain operating conditions with low speed of the high-pressure shaft or in case of engine failure, the power of the low-pressure shaft, with the clutch (9) engaged, is transferred to the high-pressure shaft gearbox and hence to the accessory drive gearbox via the conical-pulley variable transmission, which compensates for shaft speed difference, and the overrunning clutch, in order to reliably further operate the generator and other accessories with low fuel consumption or by windmilling only.

Abstract: A simplified continuously variable transmission system control provides a variable clamping force and a differential cylinder pressure manipulation to change sheave ratios. The system control uses two pumps. The first pump provides the variable clamping force. The second pump provides pressure changes to effect ratio changes. The clamping force can be varied based upon operator demand on an associated engine.

Abstract: A system and method for controlling the torque transferable by a mechanical drive between an engine and a shaft of a vehicle includes a first actuator which acts on a variable-speed drive, a second actuator which acts on a clutch to determine the degree of engagement/release of the clutch; and a measuring device for measuring the torque to or from the variable-speed drive. The first and second actuators and the measuring device are controlled by an electronic central control unit to protect the variable-speed drive and/or the clutch from mechanical overloading of the mechanical drive.

Abstract: A motor-generator system for a vehicle, in which power transmission between a crankshaft of an engine and a motor-generator is performed by a V-belt wound around pulleys thereof, includes a speed controller controlling the rotational speed of the V-belt within a predetermined range and provided on a crankshaft pulley mounted on the crankshaft. The motor-generator system, among others, can maintain the power transmission force of the V-belt at a high level.

Abstract: A pressure medium-actuated control device of an automated step-by-step variable speed transmission. The device having a control valve for controlling an actively engaged disconnectable type clutch which is disposed along a power flow path between a motor and a transmission input shaft, and a self-retaining valve located in the pressure supply of the clutch control valve for a rotational speed-dependent emergency actuation of the disconnectable type clutch. An electrical switch-off actuator is connected to the self-retaining valve such that the valve piston, of the self-retaining valve, can be moved into an idle position to lock the pressure supply of the clutch control valve in a powered state of the switch-off actuator, and into an operating position determined by the applied control pressures in the power-off state of the switch-off actuator.

Abstract: In a continuously variable transmission apparatus, by adjusting the transmission ratio of a toroidal continuously variable transmission, an output shaft can be stopped while an input shaft is left rotating in one direction by a drive source. And, when, while the vehicle is running, a select lever is operated to a select position in the reverse direction to the vehicle running direction, in a state where a clutch device is connected, the speed ratio of the continuously variable transmission apparatus is changed from a value corresponding to the vehicle running state to a value 0 capable of realizing the above-mentioned stopping state along a preset condition.

Abstract: A transmission having a plurality of gear ratios, a selector assembly for selectively engaging the gear ratios, a clutch device for selectively transmitting drive from a drive source to the transmission, and a control system for controlling a clutch torque limit, in which the control system automatically adjusts the clutch torque limit value before the selector assembly selects an unengaged gear ratio, to allow relative rotational movement between input and output sides of the clutch if the torque exceeds the predetermined value when the unengaged gear ratio is engaged by the selector assembly.

Abstract: A control system for a drive unit of a vehicle, including a reaction force establishing device controlling a speed change ratio of a continuously variable transmission, and a clutch mechanism arranged on a power transmission route from the continuously variable transmission to a wheel and in which a torque capacity thereof is controllable. A first input torque control mechanism lowers a torque to be inputted to the clutch mechanism through the continuously variable transmission, by controlling a torque of the reaction force establishing device while the torque capacity of the clutch mechanism is being controlled. The system reduces a change in a torque inputted to a clutch mechanism, in case of carrying out a speed change operation of a continuously variable transmission and engaging the clutch mechanism.

Abstract: A vehicle drive unit control system. The vehicle includes a prime mover arranged on a power transmission route from a continuously variable transmission to a wheel, a clutch mechanism arranged on a first route from the prime mover to the wheel, and a shift range or shift position can be shifted selectively between a drive range or drive position where a power can be transmitted through the first route and a non-drive range or non-drive position where a power cannot be transmitted through the first route. The control system includes a vehicle speed control demand judging mechanism judging a vehicle speed control demand in case of shifting the shift range or shift position from the non-drive range or non-drive position to the drive range or drive position; and a prime mover controller controlling torque of the prime mover based on the judged vehicle speed control demand.

Abstract: The invention provides for a vehicle drive line provided with an engine (1) capable of generating an engine torque (Te), a continuously variable transmission (2), a driven wheel (5) and two friction clutches (3, 33), a first clutch (3) being positioned in the drive line between the engine (1) and the transmission (2) and a second clutch (33) being positioned between the transmission (2) and the driven wheel (5), wherein a torque (Ta-max) that is transmissible by the first clutch (3) and a torque (Tc-max) that is transmissible by the second clutch (33) are both less than a torque (Tt-max) transmissible by the transmission (2) and, at the same time, are both essentially equal to or slightly higher than the engine torque (Te).

Abstract: Various works of a tractor or wheel loader that require frequent operations of start, stop, and switching between the forward drive and reverse drive that are repeated alternately can be performed very easily. The control apparatus comprises a speed change sensor that detects the step-on amount of a speed change pedal, an actuator that regulates the swash plate angle of a hydraulic pump based on the detection value of the speed change sensor, a transmission output unit rotation sensor that detects the revolution speed of an output shaft, and a control unit.

Abstract: A method is provided for increasing a temperature of oil in a continuously variable transmission during engine start-up, the transmission including a fluid pump and motor, and a mechanical transmission. The method includes starting the engine, maintaining the fluid pump at substantially zero displacement, and heating the transmission oil by relative rotation of a first clutch disc and first clutch hub of a first clutch assembly and by relative rotation of a second clutch disc and second clutch hub of a second clutch assembly. The method further includes maintaining a substantially zero net torque from the transmission during the heating of the oil by the first and second clutch assemblies.

Abstract: In the case where a belt return of a continuously variable transmission is not determined when the vehicle speed has become equal to or lower than a threshold value, control that causes a hydraulic actuator to have an intermediate pressure by setting a duty of a duty solenoid based on an input torque and an oil temperature and closing control are repeatedly performed, in accordance with the running and the stopping of the vehicle. As a result, it is possible to inhibit the continuously variable transmission from being shifted up due to a gradual increase in the hydraulic pressure in the hydraulic actuator caused by a line pressure seeping to the hydraulic actuator side through a small clearance in a spool of a flow rate control valve in a hydraulic circuit, and it is also possible to allow the continuously variable transmission to be shifted down.

Abstract: The present invention relates to a drive system for vehicles with at least two drivable vehicle axles (V, H), in particular for utility vehicles and farm tractors. The drive system has an infinitely variable transmission with no intermediate axle differential comprising at least a first (11) and a second (12) motor. The first motor (11) in this case is propulsively connected to a first vehicle axle (H) and the second motor (12) is propulsively connected to a second vehicle axle (V). Furthermore the drive system has a clutch (20), by which a propulsive connection can be made between at least the first (H) and the second (V) vehicle axle, wherein the position of the clutch is adjustable (20) in a range between an engaged position and a disengaged position, and a control unit (30), which actuates the clutch (20) in such a manner that its torque transmission capacity is adjusted as a function of a driving state of the vehicle.

Abstract: A continuously variable transmission for a motorcycle that provides appropriate engagement of a centrifugal clutch when a clutch shoe is worn. A control unit controls a change gear ratio to a TOP side to engage the centrifugal clutch when the centrifugal clutch is disengaged and an engine rotational speed is higher than a predetermined first rotational speed.

Abstract: A straddle-type vehicle in which drivability is ensured when starting the vehicle. The vehicle includes a control device that controls a continuously variable transmission. A plurality of driving modes “A” and “B” are set in the control device. The control device performs a first control that switches the driving mode to driving mode “A” before start of the engine; a second control that switches between driving 2modes A” and “B” in response to operation of a mode switching operation member; and a third control that limits the second control and inhibits switching from the driving mode “A” to driving mode “B”, when the control device detects that the engine has not been started.

Abstract: To prevent engine speed from increasing during low-speed operation, a transmission includes a change-gear mechanism, a centrifugal clutch, a control unit and a secondary sheave rotation sensor. The change-gear mechanism has an input shaft, an output shaft and an actuator for changing a change-gear ratio between the input and output shafts. The centrifugal clutch is connected to the output shaft. The control unit controls the actuator. The secondary sheave rotation sensor detects and outputs a rotational speed of the output shaft to the control unit. The control unit controls the actuator based on a target change-gear ratio obtained by dividing a target rotational speed of the input shaft by the rotational speed of the output shaft.

Abstract: In a method and control device for adjusting a rotational speed of a shaft of a gear change transmission of a motor vehicle, a torque required for the acceleration of the transmission and derived from a drive motor is transmitted by means of an automated clutch and using the torque the rotational speed of the shaft is precisely and rapidly adjusted to a range around a target rotational speed by defining a desired value for a position of the clutch on a rotational speed difference between a measured rotational speed of the shaft and a target rotational speed so that the gear can then rapidly be changed.

Abstract: An engine controller of the present invention is comprised of: a determining section for determining a state where an engine is not driven; a braking torque obtaining section for obtaining a braking toque acting on the vehicle; a vehicle speed sensing section for sensing a vehicle speed; an atmospheric pressure obtaining section for obtaining an atmospheric pressure value when an engine is driven; a road gradient obtaining section for obtaining a road gradient on the basis of the braking torque and the vehicle speed when the determining section determines the state where the vehicle is not driven; an atmospheric pressure correcting section which calculates a vehicle vertical travel of a downhill on the basis of the road gradient and a travel distance derived from the vehicle speed when the vehicle has descended the downhill, and corrects the atmospheric pressure value on the basis of the vehicle vertical travel of the downhill.

Abstract: A vehicle with a transmission having a crankshaft and an output shaft. A clutch located between the output shaft and a drive wheel is engaged and disengaged according to a rotational speed of the output shaft. An idle speed control device performs idle speed control to adjust an idle rotational speed of an engine. An electronic control unit (ECU) suppresses or stops the idle speed control when the clutch is engaged, or when an abnormality in the transmission is detected.

Abstract: A power unit for a motorcycle having a continuously variable transmission, which is housed in a transmission chamber inside a engine body and which accomplishes stepless changes in the transmission of power from a drive pulley shaft to a driven pulley shaft by changing the effective diameter with which a belt actually wraps around each of the drive and the driven pulleys. An input clutch is set between a crankshaft and a drive pulley and is provided on the drive pulley shaft. A starter clutch is set between a driven pulley shaft and a rear wheel and is provided on the driven pulley shaft. The switching between the engagement and disengagement of one of the input clutch and the starter clutch is hydraulically controlled. Meanwhile, the switching between the engagement and disengagement of the other one of the input clutch and the starter clutch is mechanically controlled.

Abstract: A dual ratio belt drive system for powering rotating accessories. The system comprises a clutch unit rotatably connected to a rotating shaft and an overrunning clutch mounted directly to the rotating shaft. The system also comprises a plurality of rotating accessories rotatably connected to said clutch unit and rotatably connected to said rotating shaft through said over-running clutch such that said accessories are driven by said clutch unit at a first speed ratio and driven directly by said rotating shaft at a second speed ratio, with said clutch unit operating at a predetermined value of an engine operating condition thereby defining the transition between said first and second speed ratios, with said clutch unit being engaged at engine start.

Abstract: A hydraulic pressure control device is provided that that controls hydraulic pressure of a clutch supplying torque to a continuously variable transmission while the vehicle is stopped and in a running range. The hydraulic pressure control device has an control section that estimates a clutch engagement hydraulic pressure for changing the clutch from an engaged state to a disengaged state based the hydraulic fluid pressure acting on the clutch during the stopping of the rotational movement of a primary pulley of the continuously variable transmission, and then controls regulation of the hydraulic pressure to the clutch from an engaged state to a disengaged state, when the vehicle is stopped and in the running range, so that the torque from the engine does not rotate a secondary pulley of the continuously variable transmission.

Abstract: A clutch control apparatus for a power transmission system including an input rotating member and an output rotating member. The clutch control apparatus includes a friction clutch, and a control unit. The control unit sets a first desired clutch torque setting in accordance with a clutch slip indicator; sets a second desired clutch torque setting to an amount of torque input from the input rotating member to the friction clutch; controls the clutch torque to be the first desired clutch torque setting during a starting stage of the friction clutch; controls the clutch torque to be the second desired clutch torque setting during a steady-state stage of the friction clutch; and controls the clutch torque to gradually change from the first desired clutch torque setting to the second desired clutch torque setting during a transition stage between the starting stage and the steady-state stage.

Abstract: A method is provided for controlling engagement of a clutch which carries torque before, during and after a shifting event in a transmission which is connected to a throttle-controlled engine. The method includes providing a feed forward input command which increases as the engine torque increases and decreases as the engine torque decreases. A feed-back input command is provided as a function of the error between measured clutch slip and a reference slip profile. The feed-forward input command and feed-back input command are summed to provide a clutch control command for controlling engagement of the clutch before, during and after the shifting event to allow a desired amount of clutch slip to damp excitation of the transmission.

Abstract: An automatic transmission controller for a hybrid vehicle of the present invention is used for the hybrid vehicle being a four-wheel drive vehicle and including an engine and a generator motor on a front wheel side of the hybrid vehicle and a traction motor on a rear wheel side of the hybrid vehicle. The automatic transmission controller for a hybrid vehicle includes: an automatic transmission for transmitting a driving force from the engine to an output shaft of the hybrid vehicle; and an oil pump for supplying a speed-shifting clutch of the automatic transmission with pre-pressure to eliminate play of the speed-shifting clutch, when the hybrid vehicle is driven by a driving force from the traction motor.

Abstract: A continuously variable transmission apparatus includes a toroidal-type continuously variable transmission, a planetary gear type transmission and a clutch apparatus that connects the toroidal-type continuously variable transmission and the planetary gear type transmission. The clutch apparatus includes: a low speed clutch engaged for realizing a low speed mode and disengaged for realizing a high speed, a high speed clutch engaged for realizing the high speed mode and disengaged for realizing the low speed mode and a controller. The controller controls the transmission ratio of the toroidal-type continuously variable transmission so that rotational speeds of members connected via the clutch apparatus equals with each other, and then disengages the one of the low speed clutch and the high speed clutch after engaging the other.

Abstract: A control apparatus for a power train including a continuously variable transmission and a clutch arranged in series with the continuously variable transmission is provided in which an engaging pressure of the clutch is first reduced until a slip occurs, and is then increased after detection of the slip so as to re-engage the clutch, and an engaging pressure of the clutch to be established is calculated by giving an excess pressure to the engaging pressure at which the clutch is re-engaged, such that an excess amount of the transmitted torque of the clutch is set smaller than that of the continuously variable transmission. The control apparatus is adapted to determine a learned value as a correction value of the engaging pressure that is set in advance in accordance with an input torque applied to the clutch, based on the engaging pressure calculated by giving the excess pressure to the engaging pressure at which the clutch is re-engaged.

Abstract: A continuously variable transmission is disclosed comprising a transmission input, a transmission output, and a continuously variable ratio unit (“variator”) arranged to be coupled between the transmission input (205) and output (240) by means of at least one clutch (230,250) thereby to enable transfer of drive between the input and the output at a continuously variable transmission ratio. The variator is connected to a hydraulic control circuit (50) and so subject to a hydraulic control pressure which is adjustable by the control circuit and is also influenced by changes in variator ratio. The variator is constructed and arranged such as to adjust its ratio to provide a variator reaction torque which corresponds to the control pressure. The transmission further comprising means (311,310) for adjusting the torque capacity of the clutch while it is engaged so that by controlling torque loading applied to the variator, the clutch influences the control pressure and the reaction torque.

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: The automatic clutch control device controls, regardless of the gear-shift operation, the clutch to be brought into a half-clutch state or to a perfect disconnecting state according to a running state of a vehicle from the following five viewpoints deceleration slip amount of driving wheels RL and RR; a convergence time of a driving wheel speed to the driving wheel in a pressure-down mode during a vehicle stabilizing control (for example, ABS control); a continuation time of a judder vibration; whether the vehicle is in a spinning state or not; and whether there is a possibility that an engine stall occurs during a traction control. As a result, this device can attain at least one or more objects of the improvement in stability of the vehicle, improvement in precision of the vehicle stabilizing control, improvement of comfortableness of the occupant and prevention of the occurrence of the engine stall.

Abstract: A hydraulic controller for a hydraulic actuator (6) incorporated in a power transmission mechanism, wherein an accumulator (16) is connected to an oil supply passage (14) for the hydraulic actuator (6) for supplying oil from a pump (10) via a regulator (11) and a one-way valve (12) and a lubricating oil passage (20) for the power transmission mechanism is connected to the regulator 11 in the drain side thereof, by which energy consumption can be reduced maximally even if the pump (10) is regularly driven for lubrication. It is provided with a hydraulic pressure switching means (19) capable of freely switching a setting pressure of the regulator (11) between a high pressure and a low pressure. While the hydraulic pressure of the oil supply passage (14) is higher than or equal to a pressure at which the hydraulic actuator (6) can be operated, the controller maintains the setting pressure of the regulator (11) at the low pressure to reduce a work load of the pump 10.

Abstract: The invention is directed to a method for controlling the operation of a clutch (19) which coacts with an automatic transmission stage (17). A variator controller (16) is assigned to the automatic transmission stage (17) and a contact-force control (18) is assigned to the clutch (19). Depending upon the detected and classifiable drive situations, first and second torque/contact-force reserves (13, 44) are determined which are supplied to an input quantity ME (22) of the variator controller (16) and to the contact-force control (18) for the clutch (19). The output signals (20, 21) of the variator controller (16) and the contact-force control (18) influence the operation of the automatic transmission stage (17) and the clutch (19).

Abstract: An electrically variable transmission has a pair of clutches and a first mode when the first clutch is applied and the second clutch released, a second mode when the second clutch is applied and the first clutch released, and a fixed-ratio mode when both clutches are applied. Upshifts and downshifts out of fixed-ratio are accomplished in accordance with a control based upon shift confidence factors determined in accordance with proportional and derivative input speed error quantities. Shift cycling is avoided by applying a variety of conditional tests intended to inhibit return to fixed-ratio operation.

Abstract: A control apparatus for a power train including a continuously variable transmission and a clutch arranged in series with the continuously variable transmission is provided in which an engaging pressure of the clutch is first reduced until a slip occurs, and is then increased after detection of the slip so as to re-engage the clutch, and an engaging pressure of the clutch to be established is calculated by giving an excess pressure to the engaging pressure at which the clutch is re-engaged, such that an excess amount of the transmitted torque of the clutch is set smaller than that of the continuously variable transmission. The control apparatus is adapted to determine a learned value as a correction value of the engaging pressure that is set in advance in accordance with an input torque applied to the clutch, based on the engaging pressure calculated by giving the excess pressure to the engaging pressure at which the clutch is re-engaged.

Abstract: A vehicle with an automatic engine stop/restart function comprises an engine, an automatic transmission having an oil pump driven in synchronism with the engine to supply an oil pressure to the automatic transmission, an oil pressure controller to hold the oil pressure in the automatic transmission during an automatic stop of the engine, and a control system. The control system is configured to: determine whether the oil pressure in the automatic transmission becomes lower than a predetermined value during the engine automatic stop; shift the automatic transmission into a neutral state when the oil pressure in the automatic transmission becomes lower than a predetermined value during the engine automatic stop; restarts the engine; and then, shift the automatic transmission into a drive state after the oil pressure in the automatic transmission is increased to the predetermined value by the oil pump driven in synchronism with the engine.