Abstract: The invention relates to a fuel cell system (100) with at least one fuel cell (90), each fuel cell (90) having a cathode inlet (92), and with a housing (50) in which the at least one fuel cell (90) is arranged, the housing (50) having at least one ventilation inlet (52) through which at least one ventilation fluid flows in and at least one outflow outlet (54) through which at least one outflow fluid flows out. The fuel cell system (100) further comprises a supply line (14) to the at least one cathode inlet (92) for providing a supply fluid from a first fluid source to the at least one cathode inlet (14), and a compressor (16) in the supply line (14) for compressing the supply fluid.

Abstract: A gas valve, in particular a metering valve for a gaseous medium, having a valve washer (10) which is arranged in the gas valve so as to be able to move with respect to a longitudinal axis (8), and having a valve plate (12) with a valve seat (19) formed thereon, wherein the valve washer (10) interacts with the valve seat (19) for opening and closing the gas valve, and having a first circumferential sealing edge (30) between the valve seat (19) and the valve washer (10). The valve washer (10) has a central opening (13) through which the gaseous medium passes, wherein the first circumferential sealing edge (30) surrounds the central opening (13) and wherein, in the central opening (13), there is formed a first pressure face (25) upon which the gaseous medium acts in the closing direction. Furthermore, there is arranged on the valve washer (10) a second pressure face (26) which is formed radially outside the first circumferential sealing edge (30) and on which the gaseous medium also acts.

Abstract: A gas valve, in particular a metering valve for a gaseous medium, having a valve washer (10) which is arranged in the gas valve so as to be able to move with respect to a longitudinal axis (8), and having a valve plate (12) with a valve seat (19) formed thereon, is wherein the valve washer (10) interacts with the valve seat (19) for opening and closing the gas valve, and having a first circumferential sealing edge (30) between the valve seat (19) and the valve washer (10). The valve washer (10) has a central opening (13) through which the gaseous medium passes, wherein the first circumferential sealing edge (30) surrounds the central opening (13) and wherein, in the central opening (13), there is formed a first pressure face (25) upon which the gaseous medium acts in the closing direction. Furthermore, there is arranged on the valve washer (10) a second pressure face (26) which is formed radially outside the first circumferential sealing edge (30) and on which the gaseous medium also acts.

Abstract: In a charging device for an internal combustion engine, the charging device has at least one first line for the intake of fresh air, having at least one air-gap-insulated exhaust-carrying component. This is assigned to an outlet side of the internal combustion engine. At least one regulating element for distributing an exhaust gas stream, and at least one regulating element for distributing a pre-compressed fresh air stream is provided. The air-gap insulated exhaust-carrying component has an outer chamber, through which a controllable stream of fresh air flows.

Abstract: In a charging device for an internal combustion engine, the charging device has at least one first line for the intake of fresh air, having at least one air-gap-insulated exhaust-carrying component. This is assigned to an outlet side of the internal combustion engine. At least one regulating element for distributing an exhaust gas stream, and at least one regulating element for distributing a pre-compressed fresh air stream is provided. The air-gap insulated exhaust-carrying component has an outer chamber, through which a controllable stream of fresh air flows.

Abstract: A supercharging device, especially for supercharging internal combustion engines, having a first supercharging device and an additional supercharging device, which each have one compressor part and each have one turbine part, and a supercharging pressure prevails in an intake manifold on the intake side of the internal combustion engine, and an exhaust gas counterpressure prevails in an exhaust gas manifold, on the outlet side of the internal combustion engine. A switching element is provided, in the intake tract of the internal combustion engine, between the compressor part of the first supercharging device and the compressor part of the additional supercharging device, using which, switching over is performed from the series connection of the compressor parts to the parallel connection of the compressor parts and vice versa.

Abstract: A valve actuator for operating a gas exchange valve of an internal combustion engine has a sleeve-shaped positioning piston which is connected to a valve stem, has at least two shell-shaped wedge pieces enclosing a stem end of the valve stem, whose radially outer peripheral surfaces have a conical segment which tapers off with increasing distance from the gas exchange valve and which is at least partially surrounded by a conical clamping sleeve having a mating conical inner surface and is connected to the positioning piston. The wedge pieces are axially form-fittingly and rotatably connected to a threaded bolt. A threaded segment is provided on the threaded bolt via which the wedge pieces and the conical clamping sleeve are axially attachable to one another.

Abstract: A valve actuator for operating a gas exchange valve of an internal combustion engine has a sleeve-shaped positioning piston which is connected to a valve stem, has at least two shell-shaped wedge pieces enclosing a stem end of the valve stem, whose radially outer peripheral surfaces have a conical segment which tapers off with increasing distance from the gas exchange valve and which is at least partially surrounded by a conical clamping sleeve having a mating conical inner surface and is connected to the positioning piston. The wedge pieces are axially form-fittingly and rotatably connected to a threaded bolt. A threaded segment is provided on the threaded bolt via which the wedge pieces and the conical clamping sleeve are axially attachable to one another.

Abstract: An hydraulic valve actuator for actuating a gas-exchange valve in a combustion cylinder of an internal combustion engine has an operating piston delimiting two pressure chambers, of which the lower pressure chamber acting in the valve-closing direction is permanently charged with fluid pressure via which an intake and return line can be charged by, or relieved of, fluid pressure. To brake the gas-exchange valve in the final phase of the closing procedure to reduce the set-down speed, the return line of the upper pressure chamber is split between two discharge openings, which are connected to one another and arranged in the housing with axial clearance, the upper discharge opening being coupled to a restrictor and the lower discharge opening being displaceable relative to the operating piston and disposed in its displacement path such that it may be closed thereby at a defined distance, prior to reaching its upper limit position.

Abstract: A hydraulically controlled actuator for actuation of an exhaust-side gas exchange valve of an internal combustion engine, containing a control piston that is displaceable within a cylinder and, with piston sides facing away from one another, delimits pressure chambers, of which the one pressure chamber impinges upon the gas exchange valve in the closing direction and the other pressure chamber impinges upon the gas exchange valve in the opening direction. In the actuator is provided at least one spring element, which can be brought into a preloaded state by the control piston moving in the closing direction of the gas exchange valve, and whose stored potential energy accelerates the gas exchange valve in the opening direction at least at the beginning of an opening phase, is provided. This results in a reduction in the energy expended in the context of valve actuation.

Abstract: A valve mechanism with a variable valve opening cross section disposed in a passageway of an internal combustion engine and has a gas exchange valve that is acted on by the force of a valve spring and can be slid back and forth in the axial direction inside a guide by a valve control unit. Coaxial to the gas exchange valve is a seal valve acted on by the force of a coupling spring and can be slid back and forth in the axial direction by the valve control unit. The position of the seal valve in relation to the gas exchange valve in the axial direction can be changed by an adjusting unit.

Abstract: A cylinder head for a combustion cylinder of an internal combustion engine is provided, which has at least one inlet opening and at least one outlet opening, as well as gas exchange valves which are operable by electrohydraulic valve actuators, some of which gas exchange valves function as inlet valves to control the at least one inlet opening, and some of which gas exchange valves function as outlet valves to control the at least one outlet opening. For the purpose of producing a compact, complete module which, as a separate component, may be tested for reliability and may be installed into the engine block of the internal combustion engine without additional preassembly effort, the cylinder head is provided with at least one high pressure line for supplying fluid under high pressure and at least one recycling line for recycling fluid, which have coupling openings for the hydraulic coupling of the valve actuators, and also means for fastening the valve actuators are provided.

Abstract: A device for controlling an opening cross section in the combustion cylinder of an internal combustion engine is provided, the device having a gas exchange valve integrated into the combustion cylinder and having an actuator which drives the valve element to execute a closing stroke and an opening stroke. A valve brake which is active during a residual closing stroke of the valve element is provided for the purpose of reducing the impact velocity of the valve closure member of the valve element on the valve seat in the closing stroke of the valve element. The valve brake has a hydraulic damping element with a fluid displacement volume which flows out through a throttle cross section of a throttle opening, and a control unit for controlling the throttle cross section as a function of the viscosity of the displacement volume.

Abstract: A cylinder-piston drive, e.g., an hydraulically controlled actuator for actuating a gas-exchange valve of an internal combustion engine, has an operating piston that is displaceable inside a cylinder and delimits pressure chambers by piston sides facing away from one another. The operating piston has a multipart design and is made up of at least two partial pistons that are placed inside one another, are displaceable relative to each other and strike against one another at stop faces. One pressure chamber is delimited by all, and the other pressure chamber is delimited by only a part, of the partial pistons and the sliding paths of the partial pistons not delimiting the other pressure chamber may be reduced compared to the overall sliding path of the operating piston. At least one stop face, arranged on the cylinder, may be provided against which a stop face of one of the partial pistons strikes after traveling the reduced sliding path.

Abstract: The invention relates to an electrohydraulic valve controller for controlling a gas exchange valve in internal combustion engines, having a hydraulically actuatable control valve including a control valve piston which can be acted upon, via electrically actuatable valves, by a hydraulic medium that is under pressure, and a hydraulically acting valve brake is assigned to the control valve piston. The valve brake (46) includes a temperature compensation for the hydraulic medium.

Abstract: An apparatus for controlling gas exchange valves of an internal combustion engine having hydraulic valve actuators each assigned to one gas exchange valve, with one adjusting piston acting on the gas exchange valve and two hydraulic work chambers defined by the adjusting piston the first work chamber acting on the gas exchange valve in the closing direction being constantly filled with fluid that is under pressure, and the second work chamber acting on the gas exchange valve in the opening direction can be filled with and relieved of fluid that is under pressure in alternation via a first and second electrical control valve. Two valve actuators are each triggered in alternation by the same first and the same second control valve, and the switchover of the control valves is performed during the closing state of the two gas exchange valves actuated by these valve actuators.

Abstract: The invention relates to an intake or exhaust valve mechanism with a variable valve opening cross section for use in an admission opening of an internal combustion engine and having a gas exchange valve acted on by the force of a valve spring and displaceable axially back and forth inside a guide by a valve control unit; the position of the sealing slide relative to the gas exchange valve in the axial direction is continuously variable by means of an adjusting unit. A sealing slide is disposed coaxially to the gas exchange valve, is acted upon by the force of a coupling spring, and is displaceable axially back and forth by the valve control unit.

Abstract: In a throttle valve actuator unit having a throttle valve neck that contains a pivotable throttle valve and having a drive chamber for receiving an electric drive mechanism for the throttle valve and for receiving an electric connection plug for a plug connection to a control unit, in order to reduce the production costs while maintaining the many customer-specific characteristics, the drive chamber is enclosed by a housing module, and the throttle valve neck is attached as a separate part to the housing module and secured thereto.

Abstract: A valve actuator for actuating a gas exchange valve of an internal combustion engine, having a sleeve-shaped positioning piston, which is connected to a valve shaft, having at least two shell-shaped wedge parts, enclosing a shaft end of the valve shaft, on whose radial outer peripheral surface a section shaped like a conical casing is implemented and which are axially connected on their inner side to the shaft end in a form-locked and rotatable manner, the valve actuator having a separate threaded sleeve, which has a threaded connection to the positioning piston or a component connected to the positioning piston and also axially clamps the wedge parts to a conical clamp sleeve via their section shaped like a conical casing.

Abstract: An hydraulically controlled actuator for activating a valve, especially for activating a gas-exchange valve in a combustion cylinder of an internal combustion engine, which includes two fluid-filled pressure chambers having controllable chamber volumes and a movable operating piston which delimits the pressure chambers by piston sides facing away from one another, the operating piston acting upon the valve and having an effective closing area acted upon by fluid pressure in the pressure chambers to close the valve and an effective opening area acted upon by the fluid pressure to open the valve. To influence the kinematics of the opening and closing movement of the valve, the operating piston is such that the surface area of at least one of the two effective areas changes along the sliding path of the operating piston.