Siemens Aktiengesellschaft

Michael Ulm

Friedrich Graf

Kai Storjohann

Thomas Wagner

Joachim Schafer

Karl Smirra

Roland Meyer

Reiner Bartholomaus

Andreas Wild

Roland Albert

Helmut Patze

Ralf-Johannes Lenninger

August Kammerl

Eberhard De Wille

Gerhard Gerl

Klaus Starker

Franz X Lacher

Rolf Neuhaus

Liebhart Zaiser

Wolfgang Heinrich

Franz-Xaver Lacher

An electronic-hydraulic control device for gearboxes of vehicles, preferably motor vehicles, includes a housing in which an electronic unit for controlling magnetic valves is accommodated. The valves are supplied with a pressure medium. The housing has a magnetic housing part in which magnetic parts of the magnetic valves and the electronic unit of the control device are accommodated and which lies outside the gearbox, and a hydraulic housing part in which hydraulic parts of the magnetic valves are located and which is positioned at least partially inside the gearbox housing.

Electronic-hydraulic control device for transmission of vehicles, preferably of motor vehicles

A control unit, in particular for a device provided in a motor vehicle, has a computer, a first volatile data memory and a second nonvolatile data memory connected to a temperature sensor. During operation, variable data are transmitted from the first to the second data memory. Information regarding the temperature of the nonvolatile data memory is supplied by the temperature sensor to the computer. Data from the volatile data memory are copied to the nonvolatile data memory only when the temperature that has been signaled falls below a predetermined value. Data are read from the nonvolatile data memory up to an upper temperature limit which lies above the predetermined value.

Electronic control unit, in particular for a device provided in a motor vehicle

The method is used to store and retrieve data in a control system, in particular in a motor vehicle, which contains a computer, a RAM memory and a flash memory. When the control system is switched off, operational data of different types, which can change while the control system is operating and which are required again after the control system is switched on again and which are stored in the RAM memory, are then stored in the flash memory. The flash memory is managed by means of a circular buffer method and can hold multiple copies of the operational data of the same type. When the control system is switched on, the most recent operational data of a respective type of data are determined and output to the RAM memory.

Method for storing and retrieving data in a control system, in

A control for a motor vehicle includes a transmission control and an engine control which are connected to one another through a communication channel. Functional units of the transmission control which are dependent on data of an engine and of a chassis of the motor vehicle, so-called engine-specific and chassis-specific functional units, are integrated into the engine control. Functional units having a function which is dependent on data of the transmission, so-called transmission-specific components, are contained in a computer-controlled gear shifting configuration. Data which are necessary for controlling the transmission are exchanged between the engine control and the gear shifting configuration through the communication channel 6. A shift point selection control, which can be constructed as a fuzzy control, is contained in the engine control.

Control for a motor vehicle with an automotive transmission and a smart

A control device for an automatic motor vehicle transmission has electrohydraulically actuated gearshift elements which increase the smoothness of shifting during a shifting operation, especially a shifting operation in a traction mode, by varying hydraulic pressure for actuating the gearshift elements. In a first phase of the shifting operation, in which idle travels of the gearshift elements are overcome, the pressure is rapidly made to approach a desired value through the use of a control signal (open-loop control) with a high duty cycle. In a second phase of the shifting operation, in which a transmission input moment changes from the gearshift element of an old gear over to the gearshift element of a new gear, the hydraulic pressure is built up with a high duty cycle. In a third phase of the shifting operation, in which a decrease in engine rpm required to carry out the gear change takes place, through a change in the duty cycle, the hydraulic pressure is first rapidly brought by open-loop control to a desired variable and thereafter is closed-loop controlled.

Controller for an automatic motor vehicle transmission

A control unit includes a transmission control unit and an engine control unit which are connected to one another through a communication channel. Functional units of the transmission control unit which are dependent on data from the engine and the chassis of the motor vehicle, so-called engine-specific and chassis-specific functional units, are integrated into the engine control unit. Functional units performing an operation that is dependent on data from the transmission, so-called transmission-specific components, are contained in a computer-controlled transmission ratio changing device. Data which are necessary for controlling the transmission, data for selecting or determining the transmission ratio of the transmission and configuration parameters for adapting the control unit to the respective motor vehicle, are exchanged between the engine control unit and the transmission ratio changing device through the communication channel. A shift-point selection control unit, which may be constructed as a fuzzy control unit, is contained in the engine control unit.

Control unit for a motor vehicle

A control loop, preferably for movement stability regulation in a motor vehicle, has a yaw rate sensor supplying an electrical sensor signal and a temperature sensor supplying an electrical sensor signal for compensation of temperature dependency of the sensor signal of the yaw rate sensor. A circuit configuration for evaluation of the sensor signal of the yaw rate sensor includes a first evaluation device for calculating an instantaneous yaw rate from the electrical sensor signals of the yaw rate sensor and of the temperature sensor, and a second evaluation device for adaptively determining sensor-specific characteristic parameters of the yaw rate sensor as a function of temperature. A reference yaw rate .PSI..sub.ref being calculated from measured wheel rotation speed values v.sub.1 and v.sub.r in accordance with the following formula: ##EQU1## is taken into account, where l.sub.trackw designates a distance between two centers of contact of wheels on a non-driven axle with the ground.

Circuit configuration for evaluation of the signals from a yaw rate

A control device for an automatic motor vehicle transmission reduces engine torque during a shifting operation, in particular a shifting operation in a traction mode, in order to increase smoothness of shifting. The engine torque reduction is begun at the earliest upon reaching a free-wheel point of the transmission and is ended shortly before a synchronizing point of the transmission is reached. The free-wheel point and the synchronizing point of the transmission are ascertained from rpm differences in the gearshift elements involved in the particular switching operation. Differential rpm thresholds used in the process and the intensity of the torque reduction are ascertained with fuzzy systems.

A control configuration for a motor vehicle includes an engine control and a transmission control which are connected to one another through a communication channel. A transmission is shifted by using electrohydraulic pressure control valves for actuating friction elements in the transmission. The transmission control is mounted at a transmission housing. Solenoids of the electrohydraulic pressure control valves are integrated into the transmission control. Sensor signals which are to be evaluated by the transmission control are transmitted by sensors to the transmission control wirelessly.

Automatic transmission control for a motor vehicle

A control unit for an automatic transmission in a motor vehicle includes a housing having an open bottom part with an interior. A carrier is disposed in the housing. Circuit components are disposed on the carrier. Valve coils for electromagnetic hydraulic valves are disposed in the housing and embedded in a flexible compound. A rotational-speed sensor disposed in the interior of the open bottom part is embedded in the flexible compound and thus fixed in its position in the housing. The rotational-speed sensor extends into the vicinity of a gearwheel or of some other rotating component of the transmission and detects or records its rotary motion by induction or the Hall effect.

Control unit for an automatic transmission

A motor vehicle has an engine, an automatic transmission and a chassis. A control system for the motor vehicle includes a gear ratio change control system, an engine control system and a communications channel through which the gear ratio change control system and the engine control system communicate with one another. The gear ratio change control system has function units being dependent on data of the engine and the chassis and being integrated with the engine control system. A gear ratio change unit has function units being dependent on data of the transmission. The communications channel exchanges data required for controlling the transmission, between the engine control system and the gear ratio change unit. An emergency device switches-over the gear ratio change unit, upon a malfunction of the communications channel, to receive control signals from a device not communicating with it through the communications channel.

Control system for a motor vehicle

An electrohydraulic regulating device, particularly for a motor vehicle rear axle steering assembly, includes an adjusting cylinder. An electrically actuated control valve controls a hydraulic fluid flow to the adjusting cylinder. At least one electrically actuated switching valve blocks or admits a hydraulic fluid flow. A control unit generates control signals for the control valve and the switching valve. A regulating circuit supplies a pulse-width-modulated regulating signal for regulating a mean current of the control valve. A pulse-width-modulated control signal controls a mean current of the switching valve. The same supply voltage is applied to the switching valve and to the control valve. A pulse-duty factor of the control signal for the switching valve is referred to a pulse-duty factor of an adjusting signal for the control valve.

Electrohydraulic regulating device having pulse width modulating valves

An actuating system is provided that includes a differential hydraulic cylinder containing a piston and a piston rod connected to one side of the piston. A first or head chamber (53) is defined in the cylinder and is bounded by the one side of the piston, to which the piston rod is not connected. A second or rod chamber (54) is also defined in the cylinder and is bounded by the other side of the piston, to which the piston rod is connected. An actuatable assembly is provided that is adapted to be connected to either the hydraulic cylinder or the piston rod. Finally, a proportional control valve is provided which is adapted to actuate the hydraulic cylinder by controlling the amount of fluid supply to the first chamber, wherein the supply pressure is connected to the second chamber.

Rear wheel steering system

An actuator element of an electromagnetic transducer which converts an electric current into an associated mechanical variable, for example an oil pressure, a displacement or a force, has hysteresis which is reduced by the fact that a periodic fluctuation component (jitter current) is superimposed on an actuator current. The influence of the operating parameters of the actuator element (for example of the temperature) on the hysteresis is eliminated by the fact that the frequency or the amplitude of the fluctuation component is varied in dependence on the operating parameter.

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Alteglofsheim, Germany

Michael Ulm