Abstract: A method for clutch control for wet clutches includes the following steps: determining whether a viscosity of clutch fluid lies above a predetermine threshold value; when the determined viscosity is above the predetermined threshold value: adaptation of the clutch/gear control with respect to clutch/gear control for routine operation in such a manner that additional clutch energy will be transmitted to the clutch fluid and that the clutch fluid is heated by the additional energy; and checking to see whether the viscosity of the clutch fluid during the altered clutch control operation is above the threshold value and, if that threshold value is not reached, return to clutch/gear control for routine operation.

Abstract: A power transmission device equipped with a torque biasing system and control system for controlling the torque biasing system is operable to determine a torque command and calculate a torque error based on the torque command and a model-based torque. A control signal is generated based on the torque error and the torque biasing system is operated based on the control signal.

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: When an engine is restarted after a predetermined period of being stopped oil is supplied to a clutch pack for a 2–3 and/or 3–4 shift while a transmission is engaged in the first speed for the first time since starting. The amount of oil drained during the predetermined period of being stopped is complemented in advance such that shift quality of a first 2–3 and/or 3–4 shift is enhanced.

Abstract: In a specific control state, confirmation is made whether or not the present torque limiter value exceeds a maximal value of an allowed torque value in the specific control state, and in the event that the present torque limiter value exceeds the maximal value of the allowed torque value in the specific control state, the torque limiter value is slowly lowered by subtracting a constant A1 from the present torque limiter value, while in the event of transition from the specific control state to an ordinary control state, the torque limiter value is slowly raised to the maximal torque limiter value in the ordinary control state by adding a constant A2 to the present torque limiter value. Thus, excessive change of torque at transition of a control state can be suppressed, and adverse effects on driving stability and driving performance under the specific control state can be minimized.

Abstract: A method of controlling a torque biasing system includes determining a torque command, calculating a torque error based on the torque command and a model-based torque. A control signal is generated based on the torque error and the torque biasing system is operated based on the control signal.

Abstract: A first characteristic operating value, for example the amount of transmissible clutch torque, in a motor vehicle power train with an engine is controlled by using at least a second characteristic value. The second characteristic value is subject to adaptation, if necessary, during an operating phase of the motor vehicle. The method steps are: starting the engine; and assuring that for a predetermined first time period after starting the engine, the first characteristic operating value is controlled independently of the second characteristic value, wherein the predetermined first time period depends on at least one predetermined third characteristic operating value.

Abstract: A car system and control method in which transmission shifting is controlled such that synchronizer damage is avoided. A state discrimination device detects or infers the state of each frictional surface of the synchronizers. A synchronizer for forming an intermediate transfer path is selected according to a parameter indicating the state of the frictional surface detected or inferred by the state discrimination device. Engine torque control reduces the engine torque according to a parameter indicating the state detected or inferred by the state discrimination device.

Abstract: A control apparatus for a lock-up clutch of a vehicle having a hydraulic torque transfer device equipped with the lock-up clutch between a power source and an automatic transmission is provided for controlling a hydraulic pressure of hydraulic oil supplied to the lock-up clutch when the clutch is in a slip region. The control apparatus determines whether an oil temperature of the hydraulic oil is lower than a predetermined temperature, calculates a change in input torque of the lock-up clutch, and determines whether the change in the input torque is larger than a predetermined value. When it is determined that the oil temperature of the hydraulic oil is lower than the predetermined temperature and that the change in the input torque is larger than the predetermined value, the control apparatus changes the hydraulic pressure of the hydraulic oil supplied to the lock-up clutch to a predetermined pressure for a predetermined length of time.

Abstract: A control system that generates one of a normal mode and a hot mode signal to control operation of a transmission includes a calculator that calculates a predicted temperature of a torque converter and a comparator that compares the predicted temperature to a threshold temperature. A timer generates one of the normal mode and the hot mode signals based on the predicted temperature and the threshold temperature.

Abstract: A system for protecting the clutch of a vehicle from a harmful operating state. Included in the clutch protection system are means for monitoring the operating state of the clutch, along with means for estimating the amount of energy being dissipated by the clutch. A control unit compares the estimated amount of energy dissipated by the clutch to one or more predetermined threshold energy levels. One or more actions designed to reduce the amount of energy dissipated by the clutch are initiated when the estimated amount of energy dissipated by the clutch exceeds the one or more predetermined thresholds.

Abstract: The method for control of an automated starting element such as a starting clutch or starting brake according to the thermal load of the starting clutch, which method regulates the control parameters according to a determined driving state, a tractional resistance and/or an actual clutch temperature, has one control module (1) which, below a critical control parameter limit starting from which an increased thermal load or an increased wear appears, reduced the friction work of the starting element. The reduction takes place by a reduction of the slipping time by regulating the slip in the starting element and/or by influencing at least one of the parameters (?, proportional/integral or differential parts, M_Control, p_Gradient or n_Nominal), the number of steps simultaneously used for reducing the friction work increasing with the temperature of the clutch.

Abstract: The present invention provides an apparatus for estimating clutch temperature estimates clutch temperatures that closely follow actual clutch temperature without a temperature sensor and at low cost. The apparatus employs method for calculating energy applied to the driving clutch according to the detected rotational speed difference and estimated torque and method for estimating a clutch temperature variation based on the calculated energy and estimating a clutch temperature based on the estimated clutch temperature variation.

Abstract: A control system for controlling a hybrid transmission including a two-degree-of-freedom differential mechanism is arranged to change a target prime-mover revolution speed of a prime mover so as to decrease an electric power output of first and second motor/generators when a temperature of one of the first and second motor/generators and a power device for the first and second motor/generators is higher than a predetermined temperature, wherein a target driving force of the hybrid vehicle is achieved by a demand prime-mover output generated when an output revolution speed of the hybrid transmission is kept constant and when the target prime-mover revolution speed is determined.

Abstract: In a hybrid automatic transmission of a hybrid electric vehicle equipped with a differential device having two-degree-of-freedom and at least four rotating members respectively connected to a prime mover as an input element, a drive train as an output element, and first and second motor-generators. A specified relationship among inertias of rotating systems relating to the prime mover, output element, and first and second motor-generators, a first lever ratio of a distance between an input element and the first motor-generator to a distance between the input and output elements, and a second lever ratio of a distance between the output element and the second motor-generator to the distance between the input and output elements is determined, so that a center of gravity of a lever on an alignment chart of the hybrid transmission is laid out on the output element or between the output element and the second motor-generator.

Abstract: A vehicular automatic transmission TM has a torque converter TC connected to the engine E and an automatic transmission mechanism (gear trains 13a, 13b, 14a, 14b) connected to the output side of the torque converter, the drive power from the engine for which gear shifting is performed via the torque converter and the automatic transmission mechanism is transmitted to the wheels and the vehicle is driven. The control apparatus for this automatic transmission mechanism has a towing state presumption device that presumes based on the driving conditions that the vehicle is in a towing state, and a lockup engagement increase mechanism that increases the degree of engagement of the lockup clutch of the torque converter when it is determined via the towing state determination device that the vehicle is in a towing state.

Abstract: A clutch controlling device switches the degree of engagement of a clutch according to at least one of the running state of a vehicle, the running state of an engine, or the manipulation state of a gearbox. A detecting device detects the temperature of an emission control catalyst. When a clutch controlling device decreases the degree of engagement of the clutch, the clutch controlling device increases the degree of engagement of the clutch if the temperature of the catalyst detected by the detecting device is less than a reference temperature. Accordingly, the temperature of the catalyst is increased.

Abstract: The present invention provides a method and apparatus for controlling the pressure of an actuating fluid flowing through an inching clutch. The invention includes the steps of determining an actual pressure of the actuating fluid, establishing an inching pressure threshold, comparing the actual pressure with the threshold, and controlling the actual pressure in response to the comparison. In one embodiment, the pressure is controlled using a first control algorithm in response to the fluid pressure being less than an inching threshold, and using a second control algorithm in response to the pressure being greater than or equal to the inching threshold.

Abstract: A method for controlling a damper clutch of an automatic transmission that can perform a normal shifting quality by selecting a correction value according to an outside air temperature for direct connection of the damper clutch and delaying the direct connection of the damper clutch until the operational oil temperature rises by considering the correction value to thereby enable it to get to an appropriate degree of operational oil temperature, a normal state of operational oil, the method for controlling a damper clutch of an auto transmission comprising the steps of: detecting the outside air temperature; correcting oil temperature to determine a point of time for direct connection of the damper clutch according to the determined outside air temperature; and performing controlling operations for direct connection of the damper clutch with a requirement that the operational oil temperature reaches to the correction value.

Abstract: An enhanced braking mode for a work machine includes activating engine compression release brakes while placing a torque converter in an overspeed condition. By doing so, both the engine and the torque converter contribute to decelerating the work machine. This combined braking horsepower is greater than that available using the engine compression release brakes with the torque converter in a locked condition. In addition, the braking horsepower available in this enhanced braking mode is comparable to that available with the employment of hydraulic retarders, which can be substantially more expensive, and require additional hydraulic cooling system capability. The enhanced braking mode is preferably carried out automatically by the electronic control module when the vehicle is in a retarding mode.

Abstract: After an engine (1) has started, a controller (6) starts determining whether lockup should be prohibited or permitted based on the cooling water temperature of an engine (1) or the oil temperature of a transmission (2). Once it has been determined that lockup should be permitted, the controller (6) stops determining whether lockup should be prohibited or permitted until the next time the engine (1) is started. In this way, once the conditions for determining that lockup should be permitted hold, lockup prohibition or permission based on the engine cooling water temperature or transmission oil temperature is no longer determined, so repeat engaging and disengaging of the lockup clutch (5) due to fluctuations of engine cooling water temperature or transmission oil temperature, is prevented.

Abstract: A torque-transmitting system for vehicles has a main drive clutch operable by means of a clutch-actuator, a transmission, a shift mechanism for setting the transmission ratio, a selector lever allowing the driver to select between a neutral mode or a drive mode of the transmission, and electronic control means for controlling the clutch actuator and the shift. mechanism. The electronic control means will cause the clutch-actuator to disengage the clutch when the engine is started and to re-engage the clutch if the transmission has been left in neutral mode for a preprogrammed time period while the vehicle is standing still, so as to turn the input shaft of the transmission and thereby warm up the transmission oil.

Abstract: A method for monitoring the operability of a mechanical power transmission path between an actuator of an automated transmission and a shift element of the transmission. The selection of the gear step to be engaged takes place via a control unit, and before the selection process a matching movement in the selection direction is performed with the shift element until a reference point has been detected by the control unit.

Abstract: In a control unit for a torque converter with a lockup mechanism, the surface temperature of a clutch friction material in a lockup clutch is calculated with a surface temperature calculation unit B3, the surface temperature of the clutch friction material so calculated is compared with a predetermined first allowable temperature with a surface temperature comparison unit B4, and when the surface temperature of the clutch friction material is judged to have reached or exceeded the first allowable temperature, a friction material temperature reduction operating unit B5 is started to operate to reduce the surface temperature of the clutch friction material.

Abstract: A torque converter automatic transmission of a motor vehicle is equipped with an overheat prevention system of the torque converter.

Abstract: An electronically controlled shift system is provided for a synchronized manual transmission of a motor vehicle. The shift system provides greater control of gear engagement by determining an optimum shift force at shift time, by adjusting this shift force based upon engine temperature, and by applying variable shift forces to complete a gear shift. In particular, the electronically controlled shift system comprises a manually operated shift lever for selecting a gear, a transmission control module connected to the shift lever for receiving an electrical input signal indicative of a selected gear and a dual motion actuator receiving actuation signals from the transmission control module for actuating a shift rail of the transmission to engage the selected gear.

Abstract: Disclosed is an automatic clutch intended for an engine-transmission unit in a vehicle. When in the closing stage, the clutch works under contact overpressure conditions, so that the torque transmitted by the clutch is higher by a set quantity than the engine generated torque. At low external temperature, the contact overpressure is reduced, resulting in a shorter clutch adjustment path and in less energy being required for clutching, thereby compensating for the greater stiffness of the clutch control element.

Abstract: The power train of a motor vehicle has an automated clutch and a control unit which causes one or more actuators to change the rate of torque transmission by the clutch from the engine to the transmission of the power train in response to appropriate signals from various sensors. When the transmission is shifted into gear while the engine is idling, while the brake or brakes are not applied and while the gas pedal is not depressed, the setting of the clutch is such that the transmission causes the motor vehicle to carry out a crawling movement as a result of a change of the rate of torque transmission by the clutch from the idling engine to the transmission from a first value (e.g., zero) to a second value as a function of the monitored temperature of the clutch.

Abstract: A multi-speed transmission control has a CPU which utilizes a pre-programmed computer to control the interchange of the friction devices in the transmission. A routine within the CPU is executed by the computer at least when an impending ratio interchange is sensed. The routine uses stored data which includes friction disc parameters, engine operating parameters and vehicle performance parameters to determine if the impending shift will result in sufficient excess heat energy to cause the temperature of components in the friction device to exceed a predetermined design limit. If the temperature design limit will be exceeded, a reduced energy ratio interchange is commanded utilizing adaptive parameters for the upcoming shift; and if the temperature design limit will not be exceeded, the ratio interchange proceeds without adaptive parameters.

Abstract: The invention is directed to a system for controlling operating sequences in a motor vehicle having an electronic circuit controlling (open loop and/or closed loop) the operational sequences. A temperature detecting device is provided which is mounted so as to be in thermal contact at least with parts of the electronic circuit and detects a temperature value representing the temperature of this part. A determination is made whether the detected temperature value of at least one of at least two different threshold values is exceeded. Different measures are then initiated in dependence upon which of the different threshold values is exceeded. The system considers the occurrence of high temperatures in that the system itself detects a damaging temperature and reacts appropriately by different measures to different high temperatures.

Abstract: An automatic transmission control system is provided with extreme cold logic wherein when the transmission oil temperature is below a predetermined temperature so as to cause the transmission oil to have extremely viscus characteristics, the transmission prevents faulty shifting by limiting shifts between first and third gears. The first gear is obtained by application of a single hydraulically controlled clutch element in combination with a freewheel clutch element while the third gear operation can be obtained by engagement of a second clutch element in combination with the first clutch element. Since the shift between first and third gears only requires the application of the second clutch element in combination with the already engaged first clutch element, there is no risk of torque overlap between elements.

Abstract: A transmission assembly and method for controlling a torque converter of a transmission assembly in which an electronic controller monitors the load on the vehicle power train in addition to a number of other vehicle dynamics, including the currently engaged gear ratio and the temperature of the transmission fluid. The electronic controller is operable for causing the activation of the converter clutch in response to a number of predetermined operating conditions, one of which includes the operation of the vehicle when the fluid in the torque converter exceeds a predetermined temperature and the vehicle power train is operated under a heavy load for a period of time which exceeds a predetermined time interval. Engagement of the converter clutch during such times inhibits relative rotation between the torque converter turbine and impeller, improving fuel economy and preventing the torque converter from generating a substantial amount of heat.

Abstract: An improvement is made to a torque splitting device employing hydraulic clutches so as to avoid any discontinuity in the control even when the properties of the actuating oil such as the pressure and temperature thereof deviate from standard values. For instance, when the oil temperature is low, the target value of the oil pressure for each of the clutches is modified to a lower value. Thus, it becomes possible to make less pronounced any delay in the response of the torque splitting device which may arise due to the sluggishness of the oil as it flows out of the clutch cylinder. The oil pump is typically actuated by a member rotating at a speed proportional to the vehicle speed, and the pressure output of the pump may be inadequate in a low speed range. In such a case, the target value is again reduced so as to reduce any abrupt change in the property of the torque splitting device when the vehicle is accelerated from a low speed.

Abstract: A transmission control system is proposed for reducing thermal load on engaging elements (2, 3, 4, 5) in a gearbox (1) during the starting operation. The gearbox (1) has an input shaft (7) and an output shaft (9) and at least two engaging elements or clutches (2, 3, 4, 5) each of which is allocated to a gear and comprises a first clutch half (21, 31, 41, 51) which transmits the force coming from the direction of the input shaft (7) onto a second clutch half (22, 32, 42, 52) which in turn transmits the force in the direction of the output shaft (9). Transmission elements (11, 12, 13) and shafts (7, 8, 9, 23, 33, 40, 50) are mounted between the input shaft (7) and a first clutch (2, 3) and/or between the first clutch (2, 3) and a second clutch (4, 5) and/or between the second clutch (4, 5) and a further clutch or the output shaft (9).

Abstract: An automatic transmission control system in which a specific one of friction coupling elements is selectively locked and unlocked to provide a specific gear initiates locking the specific friction coupling element to execute a gear shift to the specific gear at a level of input torque to the automatic transmission from the torque converter higher when a friction-related parameter demonstrates a high friction coefficient of the coupling element than when demonstrating a low friction coefficient.

Abstract: A lock-up control system for an automatic transmission of an automotive vehicle controls operation of a lock-up clutch for mechanically engaging the automatic transmission with the engine to enable transmission of a driving force output from the engine to the automatic transmission. An engaging force of the lock-up clutch is controlled in an predetermined operating region of the automotive vehicle, which is determined based on operating conditions of the automotive vehicle and the engine, in such a manner that an amount of slip of the lock-up clutch becomes equal to a desired value. An engaging force control amount for controlling the engaging force of the lock-up clutch is learned when the automotive vehicle is traveling in the predetermined operating region with the automatic transmission being in a predetermined speed position, and a learned value thus obtained is stored.

Abstract: A shift control apparatus for an automatic transmission provides a normal-temperature shift pattern and a high-temperature shift pattern. The high-temperature shift pattern is selected when a transmission fluid temperature satisfies a predetermined condition. The switching of the shift pattern is inhibited if the vehicle speed is lower than a predetermined speed, even when the temperature related to the transmission or engine has been judged to be higher than a predetermined temperature.

Abstract: A system and method for controlling the clutches in a vehicle powershift transmission. The control system includes a microprocessor which periodically executes an algorithm and which has a memory in which is stored a sequential set of time reference values and a sequential set of pressure values. The control system applies to each oncoming element a fill pressure pulse for fill periods which are unique for each element. The control system determines shift time values, subsequent to filling of the control elements, as a function of the fill period. The control system applies pressure signals to the control elements at times represented by the shift time values which are unique for each element. The control system determines, subsequent to a realignment time, realignment shift time values which are the same for all of the control elements.

Abstract: A shift control system controls an automatic transmission of a vehicle wherein half-lock-up control for a lock-up clutch is executed when the running state of the vehicle is in a predetermined operative range.