A gas engine is disclosed. The gas engine may include a combustion cylinder. The combustion cylinder may include an intake with an intake valve. The combustion cylinder may include an exhaust with an exhaust valve. The gas engine may include a gas admission valve assembly coupled to the intake. The gas admission assembly may include a trimmable electro-hydraulically actuatable gas admission valve to control a gas flow into the intake.

A fluid injection device includes a valve body of a cylindrical shape and a valve member, which is movably accommodated in the valve body and which has a valve surface portion to be seated on or separated from a valve seat portion formed in an inside of the valve body. The valve member has an inside passage through which urea aqueous solution flows and a communication port, which is opened at an outer peripheral surface of the valve member and at a position of an upstream side of the valve surface portion in a flow direction of air. An annular fluid passage, through which the air flows, is formed between an inner peripheral surface of the valve body and the outer peripheral surface of the valve member. The communication port is connected to the annular fluid passage at a connecting passage portion. A cross-sectional passage area of the annular fluid passage at the connecting passage portion is smaller than a cross-sectional passage area of the annular fluid passage at an upstream-side passage portion thereof.

A nozzle assembly for a fuel injector includes an injector housing having a casing and a stack within the casing, an outlet check movable within a nozzle cavity in the injector housing, and having a stop positioned within a stop cavity. A clearance is formed between the outlet check and the injector housing and fluidly connects a spring cavity to a stop cavity, and an anti-cavitation vent is formed in the stack and fluidly connects the spring cavity to a low pressure space. The anti-cavitation vent limits pressure changes in the spring cavity during fuel injection such that production of cavitation bubbles in the spring cavity is limited.

A nozzle assembly for a fuel injector includes an injector housing having a casing and a stack within the casing, an outlet check movable within a nozzle cavity in the injector housing, and having a stop positioned within a stop cavity. A clearance is formed between the outlet check and the injector housing and fluidly connects a spring cavity to a stop cavity, and an anti-cavitation vent is formed in the stack and fluidly connects the spring cavity to a low pressure space. The anti-cavitation vent limits pressure changes in the spring cavity during fuel injection such that production of cavitation bubbles in the spring cavity is limited.

A gas engine is disclosed. The gas engine may include a combustion cylinder. The combustion cylinder may include an intake with an intake valve. The combustion cylinder may include an exhaust with an exhaust valve. The gas engine may include a gas admission valve assembly coupled to the intake. The gas admission assembly may include a trimmable electro-hydraulically actuatable gas admission valve to control a gas flow into the intake.

A fluid injection device includes a valve body of a cylindrical shape and a valve member, which is movably accommodated in the valve body and which has a valve surface portion to be seated on or separated from a valve seat portion formed in an inside of the valve body. The valve member has an inside passage through which urea aqueous solution flows and a communication port, which is opened at an outer peripheral surface of the valve member and at a position of an upstream side of the valve surface portion in a flow direction of air. An annular fluid passage, through which the air flows, is formed between an inner peripheral surface of the valve body and the outer peripheral surface of the valve member. The communication port is connected to the annular fluid passage at a connecting passage portion. A cross-sectional passage area of the annular fluid passage at the connecting passage portion is smaller than a cross-sectional passage area of the annular fluid passage at an upstream-side passage portion thereof.

A fuel injector for an internal combustion engine is disclosed. The fuel injector is particularly suitable for use as a dual fuel injector, and comprises a generally tubular outer valve needle, an inner valve needle slidably received in the outer valve needle, and a nozzle body assembly comprising a tip part and a needle guide part. The tip part defines a seating region for the outer valve needle, and the needle guide part comprises a guide bore for slidably receiving the outer valve needle. In one embodiment, a lower bore region of the needle guide part defines a cavity around the outer valve needle which houses a biasing spring for the outer valve needle and a fuel. A collar for seating the biasing spring can be dimensioned to allow free flow of the fuel from the cavity into an annular accumulator volume defined between the outer valve needle and the bore of the tip part.

An internal combustion engine includes a cylinder case that includes a first geartrain disposed on a front end of the cylinder case and a second geartrain disposed on a rear end of the cylinder case. The first geartrain drives a first camshaft, and the second geartrain drives a second camshaft, the first and second camshafts having respective rotational axes that are parallel.

The present invention provides an improved fuel injection system and related method for controlling fuel heating and circulation in diesel type engines configured to use carbonaceous aqueous slurry fuels. The fuel injection system comprises: at least one fuel injector including an injector nozzle through which fuel is atomised and a fuel injector pump for pressurising fuel for supply to the injector nozzle; and a controlled bleed valve fluidly connected to each fuel injector and positioned to allow a controlled amount of carbonaceous aqueous slurry fuel to flow from the fuel injector.

A fuel injector for an internal combustion engine is disclosed. The fuel injector is particularly suitable for use as a dual fuel injector, and comprises a generally tubular outer valve needle, an inner valve needle slidably received in the outer valve needle, and a nozzle body assembly comprising a tip part and a needle guide part. The tip part defines a seating region for the outer valve needle, and the needle guide part comprises a guide bore for slidably receiving the outer valve needle. In one embodiment, a lower bore region of the needle guide part defines a. cavity around the outer valve needle which houses a biasing spring for the outer valve needle and a fuel. A collar for seating the biasing spring can be dimensioned to allow free flow of the fuel from the cavity into an annular accumulator volume defined between the outer valve needle and the bore of the tip part.