Daimler-benz Ag

Daimler Chrysler Ag

Wolfram Fleck

Gerald Hornburg

Uwe Benz

Karl-Ernst Noreikat

Thomas Klaiber

Josef Sonntag

Helmut Lorenz

Andreas Gaulhofer

Norbert Wiesheu

Jochen Sang

Michael Denda

A valve with a Laval nozzle, a valve needle movable axially in the Laval nozzle, and an inlet chamber which receives the valve needle foot, in which chamber a radially extended inlet opening terminates. The inlet chamber is separated axially from the inlet plane of the Laval nozzle by a flow channel located therebetween. The inlet chamber is delimited by the valve needle on one side and by one of the valve needle housing sections surrounding the valve needle on the other side. This valve can be used in particular as a metering valve for metering a process gas for a reaction process in a motor vehicle operated by a fuel cell.

Valve with a Laval nozzle and a method of metering a fluid

An apparatus and method for starting a vehicle which is driven by an electric drive unit supplied with electrical energy from a fuel cell. A compressor is arranged in the feed line of the fuel cell for the oxidant mass flow and is driven by an electric motor supplied with voltage from the fuel cell itself. For the purpose of starting the fuel cell, a starter motor is provided for driving the compressor which is fed from a 12 V starter battery. In addition, a safety interrogation is initiated before starting the vehicle. The fuel cell is not run up to a prescribed no-load power with the aid of the starter motor until successful termination of the safety interrogation. The drive unit is then released after this no-load power has been reached.

Apparatus and method for starting a fuel cell vehicle

A method and a system meters a supply of methanol and/or water out of a storage reservoir to a fuel-cell system by way of a conveying conduit with a metering valve. A constant mass flow is conveyed out of the storage reservoir into the conveying conduit via a conveying pump. The differential pressure between the conveying conduit and fuel-cell system is set at a predetermined value via a differential-pressure controller which is arranged in a return conduit provided between the conveying conduit and storage reservoir. The methanol and/or water supplied can be set, for example, by varying the opening and closing times of a solenoid valve. A second metering stage can be provided in the return conduit downstream of the first metering stage. When two separate metering systems are used, a common pump motor can be employed.

Method and system for metered supply of methanol and/or water to a

A method and an apparatus are provided for controlling the power of an electric drive unit in a vehicle. The drive unit is supplied with electrical energy by a fuel cell in the vehicle. On the basis of a power request which is determined from the accelerator pedal position, the air flow rate required to provide the set power from the fuel cell is calculated and set by controlling rotational speed of a compressor arranged in the air intake line to the fuel cell. To prevent the fuel cell from producing more electrical power than the drive unit can absorb, the drive unit acts limits the power request by emitting appropriate error messages. The set value for the power is fed to the drive unit and can be corrected such that the drive unit never demands more power than the amount of power instantaneously produced by the fuel cell to prevent fuel cell collapse.

Method and device for vehicle fuel cell dynamic power control

A process and an apparatus control output of an air-breathing fuel cell system which consists of an air supply line, a fuel cell, an air exhaust line, and a separate gas supply system for hydrogen gas. To control the fuel cell output, an adjustable rotary speed compressor is located in the air supply line and a variable absorption capacity expander is located in the air exhaust line. The compressor, the expander, and an additional electric motor are positioned on a common shaft. The expander converts the pressure energy contained in the exhaust air into mechanical energy and delivers that energy via the common shaft to the compressor. The air volume flow is controlled by the compressor rotary speed and adjusted to a preset value. A preset working pressure is established in the fuel cell system by adjusting the absorption capacity of the expander.

Process for supplying air to a fuel cell system

Process and apparatus for supplying air to a fuel cell system

A process and an apparatus humidify process gas for operating fuel cell systems. To ensure high efficiency, the process gas must be introduced at a predetermined temperature and humidity. A metered quantity of fine water droplets is injected into the gas supply line, by way of which the process air is humidified. If the fuel cell is operated under pressure, the process air generally has to be cooled after it has been compressed. The process air is automatically cooled as a result of a partial evaporation of the water droplets while the residual quantity of water in the form of droplets is introduced into the fuel cell.

Growing community of inventors

Erbach, Germany

Wolfram Fleck