The fuel system for introducing liquid fuel into the cylinders of a piston engine has a fuel tank for storing the fuel, a pump for pressurizing the fuel, at least one fuel injector for injecting fuel into a cylinder of the engine, and a fuel pipe for supplying fuel from the pump to the fuel injector. The fuel system further has a source of inert gas and means for introducing inert gas into the fuel pipe for purging the fuel pipe.

In metal-on-metal sealing structures, the sealing criteria employed for high pressure liquid fuel does not work when sealing gaseous fuels. An improved method for sealing a gaseous fuel between gaseous fuel conduits in an internal combustion engine comprises forming a contact band between two surfaces of a sealing structure between a first conduit and a second conduit. A width of the contact band is at least equal to the larger of a minimum contact pressure width where contact pressure is at least equal to a predetermined minimum contact pressure; and a minimum yield zone width where at least one of the two surfaces have plastically deformed.

A retainer for fastening a component, especially a fuel distributor, via a holding element to an internal combustion engine includes: decoupling elements, a fastening body and a fastening element. The fastening body is fastened to the internal combustion engine with the aid of the fastening element. In addition, the holding element is fastened to the fastening body via the decoupling elements. Moreover, a preloading element is provided that is joined to the fastening body, preloading of the decoupling elements being set by way of a predefined position of the preloading element relative to the fastening body in which the preloading element is joined to the fastening body.

A fuel delivery assembly for an internal combustion engine, including an injector cup, a fuel injector received therein, and a spring clip is disclosed. The injector cup has a circumferential wall with an external shoulder. The fuel injector has a shoulder which is axially spaced apart from the injector cup. The spring clip has a base portion with two radially compliant webs bearing against the shoulder of the circumferential wall and being in force-fit engagement with the circumferential wall. The spring clip has an axially compliant portion bearing against the shoulder of the fuel injector and being elastically deformable to bias the fuel injector in axial direction from the upper end towards the lower end.

A fuel delivery assembly for an internal combustion engine, including an injector cup, a fuel injector received therein, and a spring clip is disclosed. The injector cup has a circumferential wall with an external shoulder. The fuel injector has a shoulder which is axially spaced apart from the injector cup. The spring clip has a base portion with two radially compliant webs bearing against the shoulder of the circumferential wall and being in force-fit engagement with the circumferential wall. The spring clip has an axially compliant portion bearing against the shoulder of the fuel injector and being elastically deformable to bias the fuel injector in axial direction from the upper end towards the lower end.

A fuel rail assembly for gasoline direct injection fuel delivery to an engine. The assembly has a common rail tube. In the tube there are threaded orifices extending laterally. Injector sockets are adapted to mate with the threaded orifices. Each injector socket has a proximal nipple end region connected to the tube and a distal end region through which fuel is delivered to the engine. Screw threads are disposed around the proximal nipple end region. The screw threads include a lead thread that is received by the threaded orifices, thereby forming mechanical connections between the injector sockets and the tube that are adapted to withstand maximum pressures of fuel up tp 2900 psi.

A fuel injector cup includes a body having a first opening configured to receive fuel into the body and a second opening configured to receive a fuel injector for dispensing fuel. The cup further includes a mounting flange coupled with the body and extending therefrom, the mounting flange configured to be connected to a support surface to secure the cup to the support surface. The cup also includes a locating member coupled with at least one of the body or the mounting flange, the anti-rotation member configured to engage the fuel injector when received in the body and to orient and prevent rotation of the fuel injector relative to the body.

A fuel injector cup includes a body having a first opening configured to receive fuel into the body and a second opening configured to receive a fuel injector for dispensing fuel. The cup further includes a mounting flange coupled with the body and extending therefrom, the mounting flange configured to be connected to a support surface to secure the cup to the support surface. The cup also includes a locating member coupled with at least one of the body or the mounting flange, the anti-rotation member configured to engage the fuel injector when received in the body and to orient and prevent rotation of the fuel injector relative to the body.

A fuel injection apparatus for an internal combustion engine includes a fuel supply line in communication with a fuel tank and a fuel pump system. A fuel rail is connected to the fuel supply system and a plurality of fuel injectors. A return line extending from the fuel rail to the fuel tank. A by-pass passage extending from the supply line to the return line and including a pressure release valve having a pre-set activation pressure. A fuel temperature sensor for sensing a feed temperature of the fuel in the fuel supply system. A pressure control module that sets a first pressure set point in the fuel rail below the pre-set activation pressure when the feed temperature is below a predetermined temperature and sets a second pressure set point above the pre-set activation pressure of the pressure release valve when the feed temperature is above the predetermined temperature.

A fuel rail assembly for an internal combustion engine is disclosed. It includes a main gallery and a plurality of fuel delivery outlets. Each fuel delivery outlet has an injector cup and an injector cup mounting connection arranged between the main gallery and the injector cup. A fixing bracket is adapted to fasten the main gallery to the engine. The fixing bracket is spaced apart from the injector cup and secured to the main gallery. A fastening element is provided to secure the fixing bracket to the engine. A rigid connection member is coupled to the fixing bracket extends between the fixing bracket and one of the injector cup and the injector cup mounting connection.