Abstract: A vehicle driven by an internal combustion engine incorporating a power supply unit and including a power transmission on/off determination device that gradually opens a throttle valve of the engine to gradually increase a rotational speed of the engine, detects, as a determination value that reflects a load applied on the internal combustion engine when the speed of the engine increases to a power transmission start rotational speed, and then the throttle valve is further opened by a set angle, determines that the power transmission device is in a state of cutting the power transmission when it is determined from the determination value that the engine load is less than a preset magnitude, and determines that the power transmission device is in a state of performing the power transmission when it is determined from the determination value that the engine load is equal to or more than the preset magnitude.

Abstract: A method and arrangement for controlling a continuously variable transmission with improved response time, the continuously variable transmission having a first pulley engagable with an engine and having a second pulley drivingly connected to the first pulley by a belt. The first and second pulleys each have a fixed sheave and a movable sheave, a position of the movable sheaves defining a transmission ratio. The method and arrangement provides for disengaging the engine from the first pulley and increasing the speed of the engine to a target speed, reducing pressure to the movable sheave of the first pulley to a low value, increasing pressure to the movable sheave of the second pulley causing it to rapidly move to a new position thereby changing the transmission ratio to a target transmission ratio, increasing the pressure to the first pulley, and reengaging the engine to the first pulley.

Abstract: A method and arrangement for controlling a continuously variable transmission with improved response time, the continuously variable transmission having a first pulley engagable with an engine and having a second pulley drivingly connected to the first pulley by a belt. The first and second pulleys each have a fixed sheave and a movable sheave, a position of the movable sheaves defining a transmission ratio. The method and arrangement provides for disengaging the engine from the first pulley and increasing the speed of the engine to a target speed, reducing pressure to the movable sheave of the first pulley to a low value, increasing pressure to the movable sheave of the second pulley causing it to rapidly move to a new position thereby changing the transmission ratio to a target transmission ratio, increasing the pressure to the first pulley, and reengaging the engine to the first pulley.

Abstract: A method and apparatus for operating an automatic transmission as a function of the engine rotational speed of a variable speed internal combustion engine. Upon a failure of the electronic control system, a return home of a motor vehicle under its own power is enabled. A delivery system delivers a working medium with which a transmission ratio adjusting device is actuated by a first control device that, in turn, is controlled by a pilot pressure that can be accurately changed by a second control device to actuate the transmission ratio adjusting device. The pilot pressure for controlling the first control device is changed by a third control device as a function of the rotational speed of the internal combustion engine when an adjusting device is switched out of a normal operation position into an emergency operation position.

Abstract: The shift control of a transmission is performed on different bases depending on whether an engine is connected so as to be passively turned, or is disconnected. During the disengaged state, the shift control is performed so that the power generation efficiency of a motor-generator becomes maximized under a predetermined condition. During the engaged state, the shift control is performed so that the turning resistance of the engine becomes minimized under a predetermined condition. Therefore, during running of the vehicle, a battery can be charged through the regeneration control of the motor-generator. Even when the regeneration control is performed while the passive turning of the engine is allowed, good electric power generation efficiency can be achieved.

Abstract: A rotational driving force from an engine E in a fuel-supply termination control is transmitted through a continuously variable transmission CVT, and this transmission of the rotational driving force is controlled by the engagement of a starting clutch 5. In this arrangement, a control system terminates the fuel supply to the engine at the elapse of a predetermined time from the starting of a deceleration of the vehicle. When the control system detects that the throttle of the engine has closed, it reduces the engaging force of the starting clutch 5 to disengage the clutch into a pre-engagement condition. Thereafter, when the fuel supply to the engine is terminated, the engaging force is gradually increased to bring the starting clutch 5 gradually into engagement.

Abstract: A power transmission comprises a continuously variable transmission CVT, which transmits a rotational driving force from an engine E, a starting clutch 5, which variably sets the transmission capacity for the continuously variable transmission CVT, and a control valve CV, which controls the engagement operation of the starting clutch 5. While the engine E is in a partial cylinder operation mode, the control valve CV controls the engagement operation of the starting clutch 5 to attain a predetermined transmission capacity at a rotational speed of the engine that is higher than for a case of the engine in an all cylinder operation mode.

Abstract: A power transmission comprises an engine E with a plurality of cylinders, a belt-type continuously variable transmission CVT, which changes the rotational speed being transmitted from the engine, a control valve CV, which variably sets the line pressure used for controlling the speed change ratio of the transmission, and an electrical control unit ECU, which calculates the torque of the output shaft of the engine when the engine is decelerating in a partial cylinder operation mode. While a vehicle equipped with this power transmission is decelerating with the engine being in a partial cylinder operation mode, the control valve CV sets the line pressure in correspondence to the torque of the engine output shaft calculated by the electrical control unit ECU.

Abstract: A three-way clutch unit (9) comprising a forward clutch (91), second clutch (92) and forward one way clutch (93) which sets a power recirculation mode, a high clutch (10) which sets a direct mode, and a mode change-over valve (175) which supplies an oil pressure to one of the high clutch (10) and second clutch (92), are provided.

Abstract: A control apparatus for feedback-controlling an engaging action of a clutch disposed between an engine and a transmission of an automotive vehicle, wherein an engaging force control device is operated upon an engaging action of the clutch, for determining a control amount and feedback-controlling the engaging action on the basis of the determined control amount such that the clutch is placed in a desired state of engagement, and a control amount limiting device is operated to limit the determined control amount when the determined control amount has changed to cause an engaging force of the clutch to be reduced.

Abstract: A hybrid drive system comprises an oil pump for forcing an operating oil to a transmission, an engine operationally connected to the oil-operated transmission through a first clutch, a battery-operated traction motor operationally connected to the transmission, a battery-operated auxiliary motor operationally connected to the engine through a second clutch so as to start the engine, an oil pump for forcing an operating oil to at least the transmission, and alteration means for selectively operationally connecting the oil pump to either one of the traction motor and the auxiliary motor which rotates at a speed of rotation higher than the other.

Abstract: A system for adjusting the tension of a continuous part of a continuously variable transmissions; which is adjustable preferably with respect to its transmission ratio, the continuously variable transmission being mounted together with a vehicle engine and at least one clutch and a vehicle engine in the drive train of the vehicle, the clutch having various operating states. The essence of the invention is the adjustment of the tension at least in dependence upon the operating state of the clutch. The adjustment of the tension of the continuous part is especially advantageous when it is undertaken in dependence upon whether an adjustment of the transmission ratio of the continuously variable transmission takes place toward higher transmission ratios or to lower transmission ratios. Furthermore, the adjustment of the tension can take place in dependence upon the activation of an ABS system, ASR system and ESP system.

Abstract: A procedure for the control and regulation of a clutch in an automated stepped transmission for a motor vehicle, in which an electronic control device by means of a first or second regulation circuit determines the behavior of the clutch during three driving conditions and that a traction interrupted shifting from a first into a second gear ratio is carried out. 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: The method for monitoring the system pressure of a continuously variable transmission for motor vehicles which, via a permanent mechanical connection, is connected with the prime mover of the motor vehicle consists in that a warning signal is activated for the driver when a drop in system pressure is detected, an entry is made in the transmission fault memory, the clutch on the output side is opened, a signal is sent to the electronic engine control system to prevent uncontrolled acceleration of the engine and the vehicle speed is monitored until it falls below a preset threshold value after which the engine is switched off.

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 the hydrodynamic clutch.

Abstract: Within the scope of the method for controlling the engine rotational speed via the torque converter lock-up clutch during the starting and stopping phases of a motor vehicle having a continuously variable transmission combined with other elements of the drive train, the closing and opening of the torque converter lock-up clutch are used as implicit function so as to ensure optimum comfort via the most asymptotic adjustment possible of the rotational speeds gradients of engine and turbine during starting and by a soft, defined separation of the speed characteristic curves of the engine and turbine during stopping. When the vehicle is standing still the forward clutch is moved into standstill disengaged mode so that the torque converter lock-up clutch can be fully closed.

Abstract: A method for setting a multiplication of a continuously variable automatic transmission (CVT transmission) comprises the following steps: a) it is determined in a test module (M1, M1′) whether an operating situation is present in which a program module (M2, M2′) for adapting an existing transmission multiplication (i_v_ist) to a vehicle speed (v_F) or to an output rotational speed (n_ab) of the transmission is activated; in the negative a transmission specified multiplication (i_v_stratagy, i_v_start) is determined as new transmission specified multiplication (i_v_soll) from a characteristic field for a regular driving strategy; b) it is tested in the program module (M2, M2′) whether the vehicle speed (v_F) or the output rotational speed (n_ab) of the transmission is higher than a predetermined limiting value (v_F_limit, n_ab_limit); c) in the case of a positive inquiry, a predefined transmission specified multiplication (i_v_ABS, i_start_w) assigned to the determined operating state is s

Abstract: A method and apparatus for operating an automatic transmission as a function of the engine rotational speed of a variable speed internal combustion engine. Upon a failure of the electronic control system, a return home of a motor vehicle under its own power is enabled. A delivery system delivers a working medium with which a transmission ratio adjusting device is actuated by a first control device that, in turn, is controlled by a pilot pressure that can be accurately changed by a second control device to actuate the transmission ratio adjusting device. The pilot pressure for controlling the first control device is changed by a third control device as a function of the rotational speed of the internal combustion engine when an adjusting device is switched out of a normal operation position into an emergency operation position.

Abstract: A first side-pressure, that is supplied to cylinder 74 of the drive pulley 71 or to cylinder 78 of the driven pulley 75 as pressure determining the transmission torque capacity of continuously variable transmission mechanism 70, is supplied to a frictional engagement element, where it is used as the working hydraulic fluid pressure. The transmission torque capacity of the frictional engagement element is set to be somewhat lower than the transmission torque capacity of the continuously variable transmission mechanism.

Abstract: A method and apparatus for controlling a continuously variable transmission of a motor vehicle includes a controller that controls the speed ratio of the continuously variable transmission in accordance with a predetermined shift condition. The method and apparatus perform shift control in a specific manner during an operation of an anti-lock brake system, for example, by smoothing at least one of the rotational speed of the input shaft and the rotational speed of the output shaft, reducing a rate of change in the speed ratio during down shifting, restricting upshifting of the CVT, increasing an amount of hydraulic oil delivered from an oil pump, and/or increasing belt clamping force.

Abstract: In an apparatus for controlling a pulley side-pressure of a belt type continuously variable transmission mechanism provided, in series with a starting clutch, in a transmission of a vehicle having a function of stopping engine idling so that an engine is automatically stopped, if the vehicle start-up is controlled from the state of engine stopping in an ordinary way in which the pulley side-pressure is determined by that belt transmission torque corresponding to an output torque of the engine which is obtained by the rotational speed and the negative suction pressure of the engine, the pulley side-pressure becomes excessive by wrong judgement that the engine output torque is large, because the negative suction pressure is small at the beginning of the engine starting. The durability then deteriorates and the specific fuel consumption becomes poor.

Abstract: A starting clutch control system for a continuous variable transmission is disclosed, in which the smooth engagement in the starting clutch incorporated with the continuous variable transmission is allowed by controlling the engaging pressure exerted on the starting clutch in accordance with a torque transmitted through the continuous variable transmission. A desired value of torque to be transmitted through the starting clutch is set according to the vehicle running conditions. An actual torque transmitted to the starting clutch from the toroidal continuously-variable transmission is measured in terms of a pressure difference between the pressures developed in the cylinders of the hydraulic actuator to drive a trunnion.

Abstract: A clutch control apparatus of a continuously variable transmission comprises a changeover device for changing over an oil passage connected to an apply chamber and a release chamber from an engaged position to a released position and vice versa, a slip pressure regulating device for regulating a slip pressure to be supplied to the release chamber, a lockup control judging device for judging whether or not a lockup clutch is to be engaged or to be released according to traveling conditions of the vehicle and a control device for reducing the slip pressure after a specified time elapses since the oil passage is changed over to the engaged position, when the lockup control judging device judges that the lockup clutch is to be changed over from the released position to the engaged position.

Abstract: A vehicular transmission including an engine, a continuously variable transmission CVT and a starting clutch. The driving force from the engine is transmitted through the continuously variable transmission CVT with a speed change to a countershaft, and the starting clutch is used to transmit this driving force from the countershaft to wheels of a vehicle. The continuously variable transmission CVT is hydraulically controlled by a control valve CV which receives control signals through a line from an electrical control unit ECU. After the vehicle has decelerated and stopped, and after the engine has stopped by an idling elimination control, the electrical current that controls the control valve CV is adjusted almost to zero.

Abstract: For an automatic transmission (3) a downshift function is proposed in which, with the actuation of a brake pedal, a new downshift point (RA(NEU)) is calculated when the throttle valve is closed by adding to a basic downshift point (RS(ORD)) a characteristic variable (K1) wherein the characteristic variable (K1) is determined from a driving activity (FA) and a calculated brake pressure via a characteristic field.

Abstract: The invention concerns a system for regulating an automobile transmission whose ratio can be modified. The gear has a transmission-dependent efficiency characteristic.

Abstract: In a continuously variable chain-belt transmission, a ratio-controlling pressure is selectively applied to either one or the other of two pairs of conical disks, while a belt-tightening contact pressure is applied equally in a torque-dependent amount to both disk pairs. A pump pressure generated by a pump is regulated by an offset pressure valve to a pressure level that exceeds the ratio-controlling pressure by a preset amount and at least equals the contact pressure. A current-controlled ratio-controlling valve device directs the ratio-controlling pressure to one or the other of the disk pairs depending on whether the ratio-controlling current is above or below a neutral value. The neutral current value as well as the algorithm describing the functional relationship between the ratio-controlling pressure and the current are continuously updated while the transmission is in use.

Abstract: An infinite speed ratio continuously variable transmission is provided with a continuously variable transmission (2), fixed speed ratio transmission (3), planetary gear set (5), power recirculation clutch (9) and direct clutch (10). A target speed ratio of the infinite speed ratio continuously variable transmission is set based on a vehicle speed and an accelerator pedal depression amount. When the target speed ratio varies beyond a rotation synchronous point, a control unit (80) assigns an order of priority to control of the power recirculation clutch (9) and direct clutch (10), and control of the speed ratio of the continuously variable transmission (2), and thereby causes a real speed ratio of the infinite speed ratio continuously variable transmission to vary in the same direction until it reaches the target speed ratio (S21, S22, S31, S32, S121, S122).

Abstract: In an apparatus for controlling a starting clutch of a vehicle having a function of stopping engine idling so that an engine is automatically stopped, the starting clutch being provided in a transmission of the vehicle in series with a belt type continuously variable transmission mechanism, a load is applied to the transmission mechanism before a rise in a side pressure of the drive pulley and the driven pulley at the time of vehicle start-up from the state of engine stopping, resulting in a slipping of the belt. To avoid such a slipping, at the time of vehicle start-up from the state of engine stopping, the engaging force of the starting clutch is prevented from increasing above the creeping force which gives rise to the creeping of the vehicle until after a lapse of a predetermined time.

Abstract: In an apparatus for controlling a starting clutch of a vehicle having a function of stopping engine idling so that an engine is automatically stopped under given conditions when the vehicle is at a standstill, the starting clutch being disposed in a transmission of the vehicle in series with a belt type continuously variable transmission mechanism which receives an input of a power from the engine through a power transmission mechanism having built therein hydraulically operated frictional engaging elements, the vehicle start-up from the state of engine stopping is made smoothly at a good response.

Abstract: A clutch control device of a continuously variable transmission is provided with a clutch control part, which controls the engagement state of a clutch. The minimum engaging force, which is capable of maintaining the completely engaged state of the clutch, is predetermined to increase according to an increase in engine torque. The clutch control unit has an engaging force setting part, which sets the target engaging force for the clutch to a higher value than the minimum engaging force by a predetermined value. The clutch control unit controls the engagement state of the clutch so that the actual engaging force for the clutch can be higher than the minimum engaging force by the predetermined value. Therefore, the clutch control device can improve the fuel economy and prevent a shift shock when there is a rapid increase in the engine torque.

Abstract: When a starter clutch slips, a wheel driving force is calculated based on a transmitting torque of the clutch obtained from not an engine torque but the clutch pressure (engagement force) of the starter clutch (S21-12), whereby a road gradient is calculated using the driving force so calculated and an acceleration of a vehicle.

Abstract: The invention relates to an adjustment of the transmission ratio of a transmission having a primary end and a secondary end. The transmission is continuously variably adjusted with respect to its transmission ratio and is mounted between a vehicle engine and the drive wheels. According to the invention, means are provided by means of which a deceleration state of the vehicle of a pregivable or pregiven extent is determined. The output rpm of the vehicle engine is adjusted or controlled in dependence upon the detected rpm of the primary end in response to the determination of one such deceleration state. With the invention, it can be ensured that the vehicle with a CVT transmission comes to standstill for a transmission ratio close to the start transmission ratio even for especially intense decelerations at low speeds (30 to 60 km/hour).

Abstract: A control system for a continuously variable transmission (17), especially for control of a lock-up clutch (10) of a torque converter (2). The lock-up clutch (10) is controlled according to a strategy whereby the torque converter (2) is considered as being serially mounted with the continuously variable transmission (17). Engagement and disengagement of the lock-up clutch (10) is exclusively a function of the control of the theoretical engine speed.

Abstract: A vehicle power shift transmission (PST) is controlled by a transmission control system which implements a control method. The PST is part of the driveline of the vehicle and is shifted by an actuating mechanism. The driveline includes an engine, the PST, a clutch, a synchronized shift transmission that can be shifted by a shift lever and driven vehicle wheels. In order to simplify the operator's tasks, during the shift of the synchronized shift transmission the gear of the PST is automatically shifted so that the resulting difference in the gear ratio of the complete transmission before and after the shift is minimized. The gear of the PST is selected and shifted automatically so that the rotational speeds on both sides of the clutch differ as little as possible.

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: In an engine of an automobile, when fuel injection is restarted by the operation of the accelerator pedal from the state in which fuel supply has been cut off during deceleration, fuel injection is controlled according to one of a plurality of fuel injection patterns, which specify a specific cylinder for fuel injection and a specific cylinder for which fuel is not to be injected, and which correspond with various speed change ratios. The engine output torque is kept smooth by performing fuel injection according to that one of these patterns which corresponds to the speed change ratio when the accelerator pedal is operated. Preferably, the fuel injection patterns are determined starting from whichever cylinder initially comes up for fuel injection.

Abstract: For a transmission having a forward drive train, a reverse drive train and a starting clutch, a control apparatus comprises a clutch control valve for setting a clutch control pressure to control the engagement of the starting clutch and a reverse inhibitor valve for opening and closing a line to a reverse drive actuator. When the clutch control pressure increases to a value above a predetermined value, the reverse inhibitor valve closes the line to the reverse drive actuator.

Abstract: A method for controlling an electro-hydraulically operated infinitely variable transmission of a motor vehicle which is driven, in particular, by an internal-combustion engine, provides a control of the infinitely variable transmission according to several characteristic control curves. The characteristic control curves are selected corresponding to a driving activity which evaluates the driver's driving style or his action with respect to the control of the motor vehicle caused by a traffic situation. The characteristic control curves cover, at least in steps, the range between a characteristic control curve permitting the consumption-optimized operation of the motor vehicle and a characteristic control curve which permits the power-optimizing operation of the motor vehicle.

Abstract: A method and device for simulating properties of a fluid torque converter such as torque ratio, capacity factor and efficiency includes involving the execution of the steps of finding a plurality of parameters including a fluid passage angle and a fluid passage resistance from a vane profile of a vane wheel of a fluid torque converter, and simulating the properties of the fluid torque converter according to the parameters and an input and output torque relationship based on an angular momentum theory. The fluid passage angle is corrected according to a slip ratio between rotational speeds of input and output ends of the fluid torque converter for the purpose of accounting for the influences of the occurrence of flow separation. Good results can be obtained by correcting the outflow angle of a stator vane array by using a correction value given as a mathematical function of the slip ratio. Thus, the accuracy of simulation can be substantially improved with a minimum increase in the computer time.

Abstract: A vehicle drivetrain control system reduces the torque of a clutch to a desired level determined as a function of the engine speed during a predetermined period of time initiated by depression of a foot brake. The function is representative of torque versus engine speed characteristic of the drivetrain during coasting operation.

Abstract: A control system for a friction bypass clutch for a torque converter that forms a part of an infinitely variable transmission in a vehicle driveline having an internal combustion engine including closed loop electronic controllers for coordinated control of the speed ratio of the transmission and the rate of engagement of the torque converter bypass clutch so that the resulting turbine speed will cause the vehicle engine to operate at an ideal speed and throttle setting that will achieve maximum brake specific fuel consumption wherein the time required for reaching the ideal speed is longer than the time required to complete engagement of the bypass clutch, thus effecting smooth clutch engagement with reduced energy absorption.

Abstract: A control system of an automatic clutch for a motor vehicle has a continuously variable transmission interposed between the clutch and driving wheels, a select position sensor provided on the transmission for detecting a select position of a large reduction range and for producing a select position signal, an accelerator switch for detecting an accelerator position and for generating an accelerator signal, and a vehicle speed sensor for generating a vehicle speed signal. Tire grip condition is determined in accordance with the vehicle speed signal that wheels grip a road surface without slipping. Engine braking is detected by the accelerator signal and the select position signal. The engagement of the clutch is controlled in accordance with the grip condition and the engine braking so as to maintain an optimum control of the clutch.