An engine head assembly includes a double-walled fuel connector assembly in an engine head and forming a high-pressure fuel supply passage and a low-pressure fuel return passage. The engine head assembly also includes a fuel injector. A high-pressure fuel inlet path extends between a fuel inlet and spray orifices through an injector body in the fuel injector. A low-pressure cooling fuel outlet path extends between an injection control valve seat in the fuel injector and a cooling fuel outlet in a nozzle case of the fuel injector. Expelled cooling fuel is passed through the low-pressure fuel return passage in the double-walled fuel connector.

An improved injector cup may be used in diesel engines that fits more securely into the engine's cylinder heads to better prevent engine coolant from leaking into the fuel and/or fuel leaking into the coolant. An improved injector cup may be designed to accommodate specific engine types and sizes in order to prevent engine coolant from leaking into the fuel and/or fuel leaking into the coolant.

In a combustion cycle in which fuel for forming a homogenized air-fuel mixture in the combustion chamber is injected from the first fuel injector, ignition-use fuel for forming an ignition-use air-fuel mixture in the vicinity of the electrode part is injected from the second fuel injector, and lean combustion is performed by an excess air rate of 2.0 or more, the ignition-use fuel is injected by at least an injection rate of 1.0 mm.sup.3/ms or more for a duration of 250 μs or more in an interval from a crank angle advanced by exactly 20 degrees from an ignition timing of the spark plug to the ignition timing, and the quantity of the ignition-use fuel is 2.0 mm.sup.3/st or less.

A fuel injector assembly for use in repairing a damaged fuel injector cylinder in an internal combustion engine includes a replacement injector sleeve and a replacement injector lower body. The replacement injector sleeve is installed in the damaged fuel injector cylinder and covers a crack in the fuel injector cylinder sidewall or the fuel injector cylinder bottom wall to inhibit leakage of fuel into a cooling system of the internal combustion engine.

A fuel heating apparatus and method are disclosed where a conductive coil is wrapped around an outer surface of at least a portion of a nozzle of a fuel injector. The coil and the nozzle are inductively cooperative with each other such that the coil, in response to a variable current through the coil, induces a heating of the nozzle. The inductively heated nozzle can heat fuel passing into an engine so as to cause the fuel to combust as it exits the heated nozzle. This arrangement allows for sparkles combustion of fuel in an internal combustion engine.

The invention relates to a cooling element (38; 40) for an injection valve (1; 41), in particular for injecting a liquid reduction agent into an exhaust train of a combustion engine, having a hollow region for receiving a section of the injection valve (1; 41) and a cooling plate (8) which is circumferential around the hollow region and a face plate (7) arranged on a face of the injection valve (1; 41) which has at least one injection opening (13), which enables the spraying of liquid out of the injection valve (1; 41) through the face plate (7). The face plate (7) has at least one bowl-shaped region (7a) formed having a front wall and at least one side wall which is designed to receive an injection-side section (1a; 41a) of the injection valve (1; 41), and the cooling plate (8) and the face plate (7) are connected to each other in a liquid-tight manner such that, in a state in which a section of an injection valve (1; 41) is properly arranged in the hollow region, a cooling volume (36) circulating around the section of the injection valve (1; 41) is delimited by the face plate (7), the cooling plate (8) and the injection valve (1; 41).

An injecting apparatus for injecting a fluid under pressure into an associated chamber, the injecting apparatus including: a body, a piston movable in the body under the action of fluid pressure in the associated chamber acting from externally against the piston, the piston being operable to compress fluid to be injected in a high pressure chamber, the piston being movable against the action of fluid pressure in a control chamber whereby movement of the piston is selectively controllable by controlling the fluid in the control chamber, an injector valve and an associated injector orifice in selective fluid communication with the high pressure chamber whereby high pressure fluid from the high pressure chamber can be injected through the injector orifice upon opening of the injection valve.

A retaining ring configured for in-field repair of a fuel injector sleeve upper seal leak, comprising: a circular side wall comprising a barrel-shaped outer surface and a substantially cylindrical inner surface; wherein the outer surface comprises a lower curved portion and a central portion having a curvature that is less pronounced than the lower curved portion; and wherein the lower curved portion is configured to guide the retaining ring into the fuel injector sleeve and the circular side wall has an outer diameter at the central portion that is larger than an inner diameter of the fuel injector sleeve at a location of the upper seal leak such that the retaining ring forces the fuel injector sleeve outwardly at the location of the upper seal leak as the retaining ring is moved into an installed position.

The present invention relates to a sealing sleeve for the separated supply and discharge of a cooling medium that comprises a sealing member that is pivotally symmetrical about the longitudinal axis, a protrusion projecting radially outwardly with respect to the longitudinal axis at the upper longitudinal end of the sleeve member, a protrusion projecting radially outwardly with respect to the longitudinal axis at the lower longitudinal end of the sleeve member, a first web section and a second web section of which each one extends in the axial direction of the sleeve member and connects the upper protrusion to the lower protrusion, and a first wall region and a second wall region of which each one is bounded in the axial direction by the upper and lower protrusions and in the peripheral direction by the first and second web sections and is radially inward offset with respect to these elements, with the upper protrusion and the lower protrusion each extending continuously around the total periphery of the sleeve member and defining its maximum radial extent, and with the first wall region and the second wall region each having a radially extending passage channel to radially supply or discharge a cooling medium.

An insert device may include a body coupled with an engine cylinder head. The body has an interior surface shaped to receive and engage a distal tip of a fuel injector. The body has gas conduits and mixture conduits with gas conduits extending from inlets along an exterior surface to outlets that intersect the mixture conduits. The mixture conduits extend from inlets along an interior surface of the body to outlets on the exterior surface. The gas conduits are positioned to direct gases outside of the body into the mixture conduits. The mixture conduits are positioned to receive fuel from spray holes of the fuel injector. The mixture conduits can entrain the gas with the fuel into a fuel-and-gas mixture that is directed out of the outlets of the mixture conduits and into a combustion chamber of an engine cylinder.