A method for preventing stalling of an internal combustion engine of a motor vehicle, wherein the motor vehicle has at least one internal combustion engine, at least one automatically controlled clutch, and at least one transmission, wherein a drive shaft of the internal combustion engine can be coupled to a transmission input shaft of the transmission by means of the clutch to transmit torque, wherein the clutch is disengaged if a calculated rotational speed value of the drive shaft is less than a certain threshold value, and wherein the rotational speed value is calculated, in particular continually or continuously, as a function of a determined, current rotational speed of the drive shaft and as a function of a determined, current speed gradient of the drive shaft.

Clutch temperature management in a slip control method and arrangement for a drivetrain including a continuously variable transmission is described herein. The drivetrain includes a clutch that is so controlled as to slip when a torque higher than the usable torque attempts to pass through. The temperature data from the clutch is used to determine the usable torque. Accordingly, the clutch prevents the prime mover from stalling.

A control device for an automatic transmission is provided, which includes a vehicle-propelling friction engagement element configured to be engaged when a vehicle starts traveling, an other friction engagement element, a vehicle-propelling friction engagement element temperature detector configured to detect a temperature of the vehicle-propelling friction engagement element, an input torque detector configured to detect an input torque inputted into the automatic transmission, and a control unit comprising a lubricant supply control logic configured to control supply of lubricant to the vehicle-propelling friction engagement element and the other friction engagement element. The lubricant supply control logic switches the supply amount of lubricant to the vehicle-propelling friction engagement element according to the temperature of the vehicle-propelling friction engagement element, and switches the supply amount of lubricant to the another friction engagement element according to the input torque.

A sprag clutch has an inner race, an outer race, and a radial cavity between the races. A plurality of sprags are disposed in the radial cavity, and each sprag is configured to rotate about an axis of rotation that is perpendicular to its longitudinal axis. A sprag cage retains each of the plurality of sprags at a uniform spacing within the radial cavity, and a plurality of actuators are positioned to exert or withdraw a force upon a corresponding sprag.

The disclosure is concerned with control system and control method, for a vehicle including a driving power source, drive wheels, a first clutch, and a second clutch. An electronic control unit, which is included in the control system, places the first clutch in a half-engaged state with a predetermined clutch torque capacity, when the vehicle is started, performs start control in a first mode using the second clutch, by gradually increasing a clutch torque capacity of the second clutch from a released state, and switches the start control from the first mode using the second clutch to a second mode using the first clutch, when the increased clutch torque capacity of the second clutch reaches the clutch torque capacity of the first clutch.

The present invention relates to a method for controlling a clutch arrangement (102) of a vehicle transmission (100) arranged within a gearbox housing (104) of a vehicle, the clutch arrangement being connected to a pneumatically controlled actuator arrangement (106) for controllably arrange the clutch arrangement between a closed position and an open position, wherein the vehicle transmission further comprises at least one rotatable transmission component (108, 108′, 108″) configured to assume an engaged state, a disengaged state and an at least partially engaged state. By means of the method, the rotatable transmission component is arranged to be positioned in the at least partially engaged state for increasing the heat within the gearbox housing.

The invention relates to a method for operating a vehicle drive train (1) comprising a prime mover (2), comprising a transmission (3), and comprising a driven end (4). A friction-locking shift element (10) is provided, the power transmission capacity of which is variable and, with the aid of which, at least a portion of the torque transmitted in the vehicle drive train (1) can be transmitted between a transmission output shaft (8) and an area (6) of the driven end (4). One shift-element half is operatively connected to the transmission output shaft (8) and the other shift-element half is operatively connected to the area (6) of the driven end (4). The rotational speed of the transmission output shaft (8) is determined as a function of the rotational speed in the area (6) of the driven end (4) and also as a function of the rotational speed of the prime mover (2) and the ratio currently engaged in the area of the transmission (3). In the event of a deviation between the rotational speed of the transmission output shaft (8) determined on the output end and the rotational speed of the transmission output shaft (8) determined on the transmission-input end, which is greater than or equal to a threshold value and/or an operating temperature in the area of the friction-locking shift element (10), which is greater than or equal to a limiting value, measures reducing loads of the friction-locking shift element (10) are initiated.

Operating a drive train of a vehicle having a clutch assembly, wherein the clutch assembly is actuatable via an actuating device for the switchable transmission of a torque, wherein a first state of the actuating device, and thus a second state of the clutch assembly, is settable via a position of a drive unit of the actuating device, comprises: a) determining that a first torque request to the clutch assembly is constant; and b) determining that a first position of the drive unit is constant within the interval; and then c) controlling the drive unit with a dither function, wherein a position of the drive unit is continuously varied about the first position; and d) ending the dither function when the conditions stated in steps a) and b) are no longer met.

Related are a method and an apparatus for protecting a clutch in a vehicle driving process. The method comprises: acquiring a current oil temperature of a space where the clutch is located and judging whether the current oil temperature is within a set temperature interval or not; in a case where the current oil temperature is within the set temperature interval, detecting whether a current wheel speed difference between front shaft and rear shaft reaches to a set wheel speed difference threshold or not; and in a case where the current wheel speed difference between the front shaft and rear shaft reaches to the set wheel speed difference threshold, triggering a first protective mode that is preset to protect the clutch; and in a case where the current oil temperature is higher than the set temperature interval, triggering a second protective mode that is preset to protect the clutch.

A control apparatus for a synchronous meshing mechanism that is equipped with a gear, a sleeve, a synchronizer ring, and a hydraulic actuator is provided. When it is determined that the sleeve and the gear have been rotationally synchronized with each other in an engagement transition period of the synchronous meshing mechanism, an electronic control unit with which the control apparatus is equipped sets a command pressure for the hydraulic actuator to an intermediate pressure that is lower than a meshing completion pressure. Besides, when meshing has not been completed even after the lapse of a predetermined time from a timing when the command pressure for the hydraulic actuator is set to the intermediate pressure, the electronic control unit sets the command pressure for the hydraulic actuator to the meshing completion pressure.