A method for operating an internal combustion engine including feeding a pilot quantity of gas fuel, into a prechamber before a piston reaches a top dead center position. The method comprises autoignition of the pilot quantity of gas fuel in the prechamber, feeding a main quantity of gas fuel into the prechamber after the autoignition, and ignition of the main quantity of gas fuel by the conditions in the prechamber that are brought about by the autoignited pilot quantity. The method makes it possible to operate an internal combustion engine purely with methane or some other gaseous fuel, by means of compression autoignition of the pilot quantity.

The present invention relates to an injector for injecting gas, in particular hydrogen, preferably for directly injecting hydrogen, comprising an injector housing for holding injector components, a valve needle movably arranged along its longitudinal axis in the injector housing and configured to selectively close or release an injection opening for the flow of hydrogen therethrough, and a valve, preferably a solenoid valve, which is adapted to transfer the valve needle into a closing or releasing state by a movement along its longitudinal axis. The injector is characterized in that the valve needle is a hollow needle adapted to pass a gas, in particular hydrogen, flowing through the injection port through the interior of the hollow needle.

A gas injector for injecting a gaseous fuel. The gas injector includes a magnetic actuator having an armature, an inner pole, and a coil; a closing element, which releases and closes a gas path at a valve seat, the armature being connected to the closing element; a sealed lubricant chamber, which is filled with a lubricant and in which the armature is situated, the lubricant ensuring a lubrication of the armature; and a first flexible sealing element and a second flexible sealing element, which seal the lubricant chamber from the gas path.

A gas injector for injecting a gaseous fuel. The gas injector includes: a magnetic actuator including an armature, an internal pole, and a coil; a closing element, which unblocks and closes a gas path at a valve seat, the armature being connected to the closing element; and at least one sealing device for sealing a space in the gas injector, the sealing device including a flexible sealant and at least one stiff intermediate element joined to the sealant, the at least one intermediate element being welded to a further component of the gas injector, the flexible sealant and the intermediate element being made from at least one first material, and the further component including a second material at least at the surface, and the at least one first material of the flexible sealant and of the intermediate element differing from the second material.

An electromagnetically-driven injector may include a valve body of an on-off valve biased in a valve-closed direction by a coil spring, which is arranged in a stroking direction of the valve body, and at least one plate spring, which is provided at a right angle in the stroking direction of the valve body and arranged in such a manner as to support the valve body, and keeps a valve-closed state when energization is not provided. The at least one plate spring may include a plurality of plate springs arranged in the stroking direction of the valve body.

A metering system for a fuel atomizer includes a housing having a fuel inlet and an oxidizer inlet arranged coaxially, and an oxidizer metering device having a plurality of oxidizer channels, an oxidizer flow controller, and a fuel metering device. The oxidizer channels are spaced apart circumferentially in the housing and are arranged angled in at least one of a radially inward direction and a tangential direction to create a swirl of oxidizer flow in a mixing chamber of the fuel atomizer. The oxidizer flow controller is configured to control flow of oxidizer from the oxidizer inlet to the plurality of oxidizer channels. The fuel metering device is configured to control fuel flow from the fuel inlet to the mixing chamber.

Various embodiments include a valve assembly comprising: a housing; a needle within the housing; a first valve seat; a first valve closing part moved by the needle between a closed position and an open position; a second valve seat; and a second valve closing part moved by the needle between a closed position and an open position; a flow calibration ring fixed to the housing, surrounding the needle leaving a flow gap in between, wherein a front face of the flow calibration ring forms the second valve seat; and a stopping part fixed at the needle, wherein the stopping part and the flow calibration ring contact each other to act as an axial stop and thereby limit the maximum lift of the needle.

The invention relates to a gas metering valve (1) for a dual fuel engine (17), which has a displaceable closing body (6) which, in a position of resting against a valve seat (5), closes the gas metering valve (1) and, in a position of being lifted off from the valve seat (5), opens the gas metering valve (1). The gas metering valve (1) is actuatable in a gas operating mode, in which the gas metering valve (1) meters combustion gas via a gas channel (13) into an intake manifold (15) of the dual fuel engine (17), and in a liquid fuel operating mode, in which the gas metering valve (1) remains sealingly closed against the pressure prevalent in the intake manifold (15). The valve seat (5) is movably situated along a valve seat guide (4), the valve seat (5), owing to the combustion gas pressure in the gas channel (13), in the gas operating mode being pressed away from the closing body (6) against a stop (20) in the gas metering valve (1) and is kept in its operating position, and the valve seat (5) in the liquid fuel operating mode being sealingly pressed by the pressure from the intake manifold (15) against the closing body (6).

The invention relates to an electromagnetically actuatable gas valve for metering a gaseous fuel into a suction tract of a motor, in particular a gas or diesel gas motor, comprising a valve seat (1) which is designed as a flat seat and which has multiple annular webs (3) that are arranged in a concentric manner and are connected via at least one radially running web (4) in order to delimit circular or semicircular through-flow openings (2). The electromagnetically actuatable gas valve further comprises a movable valve plate (5) which sealingly interacts with the valve seat (1) and which has multiple annular sealing webs (6) that are arranged in a concentric manner and can be brought into an overlapping arrangement with the circular or semicircular through-flow openings (2) of the valve seat (1). According to the invention, the rigidity of the valve seat (1) and/or the valve plate (5) is substantially constant in the radial direction, the rigidity of the valve seat (1) being greater than the rigidity of the valve plate (5). The invention further relates to a method for increasing the seal of an electromagnetically actuatable gas valve.

Fuel injection accuracy of gaseous fuel injectors is important for efficient engine operation. However, the performance of the injectors varies from part to part and across their lifetime, and when an injector is under performing according to its specification it is often unknown what is causing the problem. An apparatus for operating a gaseous fuel injector in an engine comprises a mass flow sensor that generates a signal representative of the mass flow rate of the gaseous fuel in a supply conduit in the engine. A controller connected with the injector and the mass flow sensor is programmed to actuate the injector to introduce gaseous fuel into the engine; determine the actual mass flow rate of the gaseous fuel based on the signal representative of the mass flow rate; calculate a difference between the actual mass flow rate and a desired mass flow rate; and adjust at least one of on-time of the gaseous fuel injector and a magnitude of an injector activation signal by respective amounts based on the difference when the absolute value of the difference is greater than a predetermined value.