Abstract: A hydraulic system including a multi-flow hydraulic pressure supply unit, especially a dual-flow hydraulic pressure supply unit, such as a pump, by which a volumetric flow of pressurized fluid is supplied to a hydraulic-fluid-operated device. A valve arrangement is provided either for switching between the individual pump flows or for interconnecting the individual pump flows.

Abstract: A power-split transmission having several ranges of transmission ratios with continuously variable speed reductions. A drive shaft is connected to two shafts of a variable speed drive unit via a distributor gear whose shafts are in turn connected with the input shafts of a parallel gearbox via respective clutches. Two ranges of ratios only differ from each other through the reduction of the input shaft of the parallel gearbox and their output shafts. An additional embodiment includes a variable speed drive unit, a first planetary drive that is connected with a drive shaft, an input shaft of the variable speed drive unit and a connecting shaft, as well as a second planetary drive that is connected with the connecting shaft of the output shaft of the variable speed drive unit, and an output shaft and an electric motor that is nonrotatably connected with the connecting shaft.

Abstract: A method for determining a slip value describing the reliability of torque transmission between two conical disk pairs of a continuously variable transmission. The conical disk pairs are frictionally engaged by an endless torque-transmitting component. The contact pressure between at least one conical disk pair and the endless torque-transmitting component is modulated, and the slip value is determined from the difference in rotational speeds of the conical disk pairs upon modulation of the contact pressure. The pressure modulation is carried out at a modulation frequency that is above the transmission ratio adjustment frequency of the transmission and at a predetermined amplitude.

Abstract: A method and a system for reducing a jerk produced by the range shift of a transmission with a power division arrangement. The transmission includes a variable speed drive in the form of a continuously variable transmission, and a pair of planetary gear sets and a pair of shift clutches to enable power to be divided between two branches within the transmission. During a range shift between two operating ranges the variable speed drive is acted upon by a short-term transmission ratio adjustment impulse in such a way that a cancellation jerk caused thereby the adjustment impulse weakens the jerk caused by the range shift.

Abstract: An active roll stabilization system of a vehicle having an axle with at least two wheels, wherein the axle is provided with a roll stabilizer that is actuated by means of a hydraulic device. The hydraulic device is actuated and controlled by at least one pressure control valve with a preselected pressure level by a pressure supply device, such as a pump. In order to reduce the costs for producing such an active roll stabilization system, the pressure control valve is pilot-operated by a pressure control pilot valve.

Abstract: A method for determining a slip value describing the reliability of torque transmission between two conical disk pairs of a continuously variable transmission. The conical disk pairs are frictionally engaged by an endless torque-transmitting component. The contact pressure between at least one conical disk pair and the endless torque-transmitting component is modulated, and the slip value is determined from the difference in rotational speeds of the conical disk pairs upon modulation of the contact pressure. The pressure modulation is carried out at a modulation frequency that is above the transmission ratio adjustment frequency of the transmission and at a predetermined amplitude.

Abstract: A method for diagnosing contact pressure security in a continuously variable transmission having conical disk pairs and a contacting endless belt. Contact pressure forces between the disks and the belt are modified at a given transmission ratio, at a defined input and/or output torque, and at a contact pressure having a defined zeta ratio value between the contact pressure force on the input disk set and on the output disk set. The input and/or output torque is held constant. The resulting change of transmission ratio is determined, and based upon the transmission ratio change the contact pressure security is assessed based upon the deviation between the existing pressure security and an optimum pressure security.

Abstract: A branched power transmission having several transmission ratio ranges with a steplessly adjustable transmission ratio. A drive shaft is connected to both shafts of a variable speed unit through a distributor transmission, which shafts in turn are connected with the input shafts of a parallel gearbox through respective clutches. Two transmission ratio ranges differ from each other through the transmission ratio of an input shaft of the parallel gearbox and its output shaft. Additionally, the power-producing transmission can include an electrical machine. A further embodiment includes a variable speed unit, a first planetary transmission connected with a drive shaft, the input shaft of the variable speed unit and a connecting shaft, and a second planetary transmission that is connected with the connecting shaft of the output shaft of the variable speed unit and an output shaft, and an electrical machine that is non-rotatably connected with the connecting shaft.

Abstract: In a process which is for controlling and/or regulating an automated clutch, in particular in the drive train of a vehicle, and in which an actuating element, whose position determines the clutch torque transmissible by the clutch, is actuated for setting a predefined clutch torque according to a characteristic curve, the actuating element is actuated according to a characteristic curve which in a first range of the clutch torque specifies the clutch torque as a function of the position of the actuating element and in a second range of the clutch torque specifies the clutch torque as a function of the force applied to the clutch by the actuating element.

Abstract: A method and apparatus to save fuel and to make efficient use of the possibilities of a power train including a transmission having a continuously variable transmission ratio. If the vehicle velocity exceeds a prescribed velocity the fuel supply to the engine is shut off, kinetic energy of the vehicle is stored in an energy storage device, and the transmission ratio of the transmission is shifted in the direction of a lower transmission ratio. If those measures are not sufficient the vehicle brakes are operated.

Abstract: A method and apparatus for carrying out a drive belt slippage regulation in a continuously variable transmission. A driving disk set and a driven disk set are connected together for torque transfer by an endless torque-transmitting element in which a power ratio between the driving disk set and the driven disk set of a variable speed drive is set as a function of a safety margin value.

Abstract: A method for controlling the adjustment of a continuously variable transmission in which pairs of conical disks are adjustable relative to each other so that transmission ratios can be set continuously between first and second shafts on which the respective conical disk pairs are positioned. In respective absolute end positions of the adjustable disks the transmission ratio assumes an extreme value. A control system provides that in a first adjustment range the adjustable disks are always kept within relative end positions that are at least at a defined distance from the absolute end positions. In a second operating state, the adjustment of the adjustable disks is controlled in such a way that the adjustable disks can be moved within a second adjustment range over the entire adjustment distance to the absolute end positions, so that in the second operating state a maximum possible spread of the transmission is utilized.

Abstract: A method and apparatus for regulating the contact force between two frictionally-engaged torque-transmitting components of a motor vehicle drive system. A contact force between an endless torque-transmitting device and a pair of conical disks of a continuously variable transmission is determined by an adjusting value that is a function of a preliminary adjusting value and a regulator output value. The preliminary adjusting value is determined by the value of at least one operating parameter of the drive system, and the regulator output value is determined by comparing the actual value of an operating parameter with a target value of the operating parameter.

Abstract: An active roll stabilization system of a vehicle having an axle with at least two wheels, wherein the axle is provided with a roll stabilizer that is actuated by means of a hydraulic device. The hydraulic device is actuated and controlled by at least one pressure control valve with a preselected pressure level by a pressure supply device, such as a pump. In order to reduce the costs for producing such an active roll stabilization system, the pressure control valve is pilot-operated by a pressure control pilot valve.

Abstract: Method for adapting a relationship stored in an electronic control unit, between a moment transmittable by a clutch, and a control variable for controlling an actuation unit of the clutch, which clutch is arranged in an automated motor vehicle drive train with a torque detection device arranged between the clutch and a transmission with a steplessly changeable transmission ratio for producing an output parameter dependent upon a detected moment and the momentary transmission ration of the transmission, by which method the moment transmitted by the clutch is calculated from the momentary transmission ratio and the value of the output parameter, and in an operating condition of the clutch in which the transmittable and transmitted moment of the clutch are equalized, the transmitted moment is coordinated with the control variable as an updated transmittable moment.

Abstract: A method for determining a slippage value that shows a slippage condition between two components that transmit torque through frictional engagement, in particular such components that are contained in the power train of a motor vehicle. The effect on the difference in rotational speed between the components of a change in an excitation that influences the slippage condition is analyzed, and the slippage value is determined therefrom. A non-uniformity of rotation of at least one of the components is utilized as the excitation.

Abstract: A method and apparatus for determining a slippage setting between two components that transmit force through frictional engagement. One component is driven by a drive unit and the other component is an output member for driving a driven unit. A contact force that brings about the frictional connection between the components is variable. The method includes determining at least one operating parameter of at least the drive unit or of the driven unit, and establishing a desired slippage value setting corresponding to the desired slippage setting that is determined from a predetermined relationship between at least one operating parameter and the slippage value.

Abstract: A method and apparatus for determining a motion transmission value that provides security of motion transmission between two components that transfer motion through frictional engagement. The motion transmission value provides security of motion transmission through the reaction of the motion transmitted to a change in the contact force between the components that are frictionally engaged. The contact force is modulated in a predetermined frequency range during the motion transmission, and the change in the motion transmitted during the modulation of the contact force is detected. The change in the motion transmitted is evaluated using a filtering process, and the motion transmission value is determined as the result of the evaluation.

Abstract: An automatic transmission in the form of a belt-driven conical-pulley transmission having conical disk sets on the power input and power output sides, and an endless torque-transmitting member interconnecting the input side and the output side disk sets for transmitting torque therebetween. At least one stop at at least one of the end positions of at least one axially displaceable disk is provided with a cushioned retarding component for minimizing disk impact loads.

Abstract: A method and apparatus for regulating the transmission ratio of a continuously variable transmission. A set point value for adjusting the transmission ratio can be changed as a function of the operating parameters of a power train that includes the transmission. The set point value is composed of an initial control value and a regulating value. The initial control value depends on at least two operating parameters of the transmission. The set point value is updated to take into account changes that occur during operation of the transmission.