Patent application number | Description | Published |
20080293544 | PROCESS FOR ACTUATING A TRANSMISSION MECHANISM - A process for actuating a transmission mechanism having hydraulic shifting elements for changing gear ratios by using electric actuators to adjust the actuating pressures of the shifting elements. Upon a request from an engine start/stop function for shutdown of an engine, the flow of electrical current to the actuators is changed from an operating level to a standby level depending upon the operating pressure of the shifting elements. Upon the request for startup of the engine, the flow or electrical current is changed from the standby level to the operating level. A system pressure in the hydraulic system is zero when the engine is shutdown, and the power consumption in the transmission mechanism is lower at the standby level than the operating level. | 11-27-2008 |
20080296124 | Hydraulic System in Motor Vehicles - A hydraulic system in motor vehicles with at least one hydraulically actuated clutch, which entails minimized control complexity for supplying the clutch with hydraulic oil and which takes up less structural space. These characteristics are achieved essentially in that the pressure control of the hydraulically actuated clutch is effected directly and exclusively by an electrically driven and electronically controlled oil pump. | 12-04-2008 |
20090112425 | Method for Operating an Automatic Gearbox - A method of operating an automatic transmission of a motor vehicle, in particular a variable-speed transmission. The automatic transmission includes at least five shift elements, at least three of which are engaged in a forward and a reverse gear to transfer torque or force. When disengaging gears for shifting the automatic transmission from a forward or reverse gear to a neutral position, at least one of the at least three shift elements that are engaged in the respective forward or reverse gear is completely disengaged. | 04-30-2009 |
20090176612 | Method for Operating an Automatic Gearbox - A method for operating an automatic transmission of a motor vehicle, in particular a variable-speed automatic transmission. The automatic transmission has five shift elements and for transferring torque or force in a forward gear and in a reverse gear at least three of the five shift elements are engaged. In a neutral position of the automatic transmission, to prevent torque or force flow at least one of the shift elements that are engaged in the respective forward or reverse gear is fully disengaged. | 07-09-2009 |
20090177361 | AUTOMATIC TRANSMISSION FOR A MOTOR VEHICLE - An automatic transmission of a motor vehicle driven by an internal combustion engine with a transmission oil circuit, a main oil pump, mechanically driven by a combustion engine, and an auxiliary oil pump ( | 07-09-2009 |
20100312423 | METHOD AND DEVICE FOR CONTROLLING A PARALLEL HYBRID DRIVE-TRAIN OF A VEHICLE - An method for controlling a parallel hybrid drive-train of a vehicle comprising an automatic transmission and a combustion engine which is connected, via a first shifting device, to an electrical machine, which is connected, via a drive shaft, a starting clutch positioned in the transmission. To guarantee safety and high drive comfort of the vehicle during failure of the starting clutch, shifting failures of the starting clutch are monitored. If a shifting failure is recognized, predetermined contingency procedures are initiated and executed in which either continued drive of the vehicle or slowing down of the vehicle to a stop is possible. A device comprises a monitor with a sensor and parts for analyzing and recognizing shifting failures of the starting clutch. Control parts initiate and execute contingency procedures such that a continued drive operation or slowing down of the vehicle to a stop is possible. | 12-09-2010 |
20110281685 | METHOD FOR OPERATING A VEHICLE HYBRID DRIVE TRAIN HAVING AN INTERNAL COMBUSTION ENGINE AND HAVING AN ELECTRIC MACHINE - A method of operating a vehicle hybrid drive train comprising an internal combustion engine and electric machine whose torque is applicable to a drive output of the drive train. The drive train comprises a clutch arranged between the internal combustion engine and electric machine, an oil pump connected in the drive train downstream of the clutch in relation to the internal combustion engine, and the oil pump can be driven by the internal combustion engine and the electric machine, and a transmission which comprises a shifting elements for producing various gear ratios and which is supplied with hydraulic fluid by the oil pump in an operating-status-dependent manner. The speed of the electric machine is set independently of the speed of the internal combustion engine, in order to supply the transmission with a flow of a volume hydraulic fluid required for the operating point of the transmission present at the time. | 11-17-2011 |
20120115676 | METHOD FOR CONTROLLING A HYBRID DRIVE TRAIN OF A VEHICLE - A method of controlling a hybrid drive-train of a vehicle in which the hybrid drive-train comprises a combustion engine having a driveshaft, an electric machine that can be connected to the driveshaft of the engine by a clutch, an automated transmission with an input which is connected to the rotor of the electric machine, and shifting elements for shifting between two gears. During electric driving operation with the engine stopped and the clutch disengaged, the engine can be drag-started in combination with a downshift in the transmission. Drag starting of the engine is carried out by disengaging the frictional shifting element to be disengaged to below a slipping limit, engaging the clutch until the engine reaches or exceeds its minimum starting speed, starting the engine self-starts, substantially disengaging the clutch, separately adjusting the engine and electric machine to the synchronous speed of the target gear, and fully engaging and disengaging associated shifting elements. | 05-10-2012 |
20120186376 | TRANSMISSION DEVICE AND METHOD FOR OPERATING A TRANSMISSION DEVICE - A transmission device has at least one electro-hydraulic transmission control unit and a method of operating the transmission device having a plurality of gear wheel that can be engaged and disengaged from a force flow by fluidically actuated shifting elements. A piston space of a first shifting element, delimited by a second functional surface of the actuating piston of the first shifting element, is made separate from a piston space of a second shifting element, delimited by the first functional surface of the actuating piston, and an area of the second shifting element, that carries an actuating pressure, or an area of the first shifting element, that carries an actuating pressure, is, or can be, connected to the piston space delimited by the second functional surface of the actuating piston of the first shifting element. | 07-26-2012 |
20120238404 | METHOD FOR OPERATING A DRIVETRAIN - A method of operating a drive train having a hybrid drive including a combustion engine and electric motor, a clutch located between the engine and the motor, a transmission, a starting element and a brake pedal. For electric crawling from a state in which the clutch is disengaged, the brake pedal is activated and the combustion engine is turned off, initially the starting element is brought to or maintained at a filling pressure. Next, the rotational speed of the electric motor is adjusted to be higher, by a defined slippage rotational speed, than a transmission side rotational speed. When this slippage is reached, the starting element is further engaged to create a crawl torque at the output. The electric motor continues at rotational speed control so that the slippage is maintained. | 09-20-2012 |