An injector includes a nozzle body extending along a longitudinal axis and at least one spray hole extending through a portion of the nozzle body to output a fluid from the injector. The spray hole includes at least one groove. The groove is configured to facilitate efficient mixing of the fluid with air or other surrounding materials for enhanced performance of the injector and/or other components associated with the injector.

An injector includes a nozzle body extending along a longitudinal axis and at least one spray hole extending through a portion of the nozzle body to output a fluid from the injector. The spray hole includes at least one groove. The groove is configured to facilitate efficient mixing of the fluid with air or other surrounding materials for enhanced performance of the injector and/or other components associated with the injector.

Methods and systems are provided for continuously estimating a direct injector tip temperature based on heat transfer to the injector from the cylinder due to combustion conditions, and heat transfer to the injector due to flow of cool fuel from the fuel rail. Variations in the injector tip temperature from a steady-state temperature are monitored when the direct injector is deactivated. Upon reactivation, a fuel pulse width commanded to the direct injector is updated to account for a temperature-induced change in fuel density, thereby reducing the occurrence of air-fuel ratio errors.

The present disclosure provides a fuel injector seal assembly comprising a seal member comprising a first section, a second section and an annular recess disposed in the first section, the first section having a first diameter and the second section having a second diameter wherein the first diameter is greater than the second diameter; and a sleeve member comprising a first end received by the first section of the seal member, the sleeve member further including a lengthwise portion configured to press fit around a nozzle housing of a fuel injector to cause heat transfer from the nozzle housing toward a body portion of the fuel injector.

A protective structure for a fuel pump includes a protector including a connecting wall, a first protective wall, and a second protective wall. The first protective wall and the second protective wall are disposed outside the fuel pump assembled to an internal combustion engine. A standing surface of the second protective wall on a side opposite to a second base end surface in a standing direction of the second protective wall includes a curved surface that is concave on the second base end surface side and that becomes closer to the second base end surface side as the curved surface becomes farther from the first protective wall.

A resilient seal member disposed in an alignment groove of an accumulator body centers the accumulator body in an oversized accumulator bore of a cylinder head to prevent assembly damage. The seal member can compress to allow the accumulator body to move off center within the accumulator bore so that an end may be received by and form a seal with a port of a fuel injector. The alignment groove and the seal member are configured so that cooling fluid can flow past the seal member when the accumulator body is installed. In one implementation, the accumulator body includes at least one fluid flow channel at the alignment groove having a depth greater than the alignment groove so fluid can flow through the channel to pass the seal member.

A resilient seal member disposed in an alignment groove of an accumulator body centers the accumulator body in an oversized accumulator bore of a cylinder head to prevent assembly damage. The seal member can compress to allow the accumulator body to move off center within the accumulator bore so that an end may be received by and form a seal with a port of a fuel injector. The alignment groove and the seal member are configured so that cooling fluid can flow past the seal member when the accumulator body is installed. In one implementation, the accumulator body includes at least one fluid flow channel at the alignment groove having a depth greater than the alignment groove so fluid can flow through the channel to pass the seal member.

A fuel injection apparatus for a piston engine includes a fuel injector body in which an injector needle is provided, which injector needle is arranged to prevent or allow fuel injection flow from the injection apparatus based on the position of the injector needle. The position is effected by a pressurized control fluid so that by applying the pressurized control fluid the needle may be urged towards its closed position and by reducing the pressurized control fluid the needle may be allowed to move away from its closed position. The injection apparatus includes a flow path for the control fluid, wherein the flow path for the control fluid comprises a restriction section providing a restriction effect to the control fluid flow. The restriction section includes at least one temperature-effected member providing a temperature-dependent restriction effect.

Methods and systems are provided for continuously estimating a direct injector tip temperature based on heat transfer to the injector from the cylinder due to combustion conditions, and heat transfer to the injector due to flow of cool fuel from the fuel rail. Variations in the injector tip temperature from a steady-state temperature are monitored when the direct injector is deactivated. Upon reactivation, a fuel pulse width commanded to the direct injector is updated to account for a temperature-induced change in fuel density, thereby reducing the occurrence of air-fuel ratio errors.

An apparatus and method are disclosed for an injector assembly including an injector tip having a prechamber, such as a permanent, passive prechamber (PPPC), and a nozzle combustion shield (NCS) to mitigate pre-ignition events, such as knocking, caused by overheating of the prechamber. The NCS has a thermal conductivity greater than the injector tip. The NCS optionally includes a barrel forming a slip fit with the cylinder head bore and forming a press fit with the injector tip. The NCS also optionally includes a brim to form a combustion seal with a cylinder head. As the spark plug ignites a fuel charge in the prechamber, heat is absorbed into the injector tip, flows into the NCS barrel, out of the NCS brim, and into the cylinder head for cooling via a cooling jacket.