A characteristic determining device is provided which determines fuel injection characteristics of a plurality of fuel injectors for an internal combustion engine. The characteristic determining device includes a pressure sensor and a plurality of pipes each of which connects between the pressure sensor and one of the fuel injectors. The pressure sensor is designed to have a plurality of pressure inputs from the respective fuel injectors through the pipes and outputs a signal indicative of a level of pressure in each of the fuel injectors. The characteristic determining device analyzes the signals from the first pressure sensor to determine the fuel injection characteristics of the respective fuel injectors. These arrangements result in a simplified structure of the characteristic determining device and a decreased manufacturing cost thereof.

The fuel injection conduits in a multipoint device surrounding a so-called pilot central injection device include tubes of circumferential orientation. By separating the injection conduits from each other, it is possible to attribute to them different head losses which compensate the differences in length that the fuel has to travel: a uniform flow of fuel may be hoped for, for each of the injection holes. The tubes are individual but joined to form a crown that is unitary or composed of two almost symmetrical unitary portions, which lends itself well to manufacture by addition of material.

Movement of a valve body in an unspecified direction due to a minute clearance existing between a valve body and a guide changes the flow of fuel flowing into injection holes every injection, thereby leading to variation in respective beams of spray from the injection holes and the flow rate of injection between the injection holes. Provided are a valve body that sits on or separates from a seat; a plurality of guides that slidably guide the valve body; and a plurality of flow channel portions each formed between each guide adjacent circumferentially. Then, among the plurality of flow channel portions, the cross-sectional area of the first flow channel portion on a horizontal plane orthogonal to the central axis of the valve body is smaller than each of the cross-sectional areas of the remaining flow channel portions on the horizontal plane.

A dual fuel system for an internal combustion engine includes a first fuel supply of a liquid pilot fuel, a primary fuel supply of a liquid primary fuel, and a dual fuel injector. The dual fuel injector includes a spill valve fluidly connected with a plunger cavity and movable to control a start of injection and an end of injection, and an admission valve. The admission valve is movable to admit a pilot fuel into the fuel injector, such that the pilot fuel is conveyed through an outlet check to form, within a primary fuel passage fluidly connected to the plunger cavity, a segmented fuel charge of leading pilot fuel and trailing primary fuel by displacing some of the primary fuel. The liquid pilot fuel may be a higher cetane/lower octane liquid fuel, and the primary fuel may be a lower cetane/higher octane liquid fuel.

A liquid injector for injection of liquids into internal combustion engines is provided. The injectors have a plurality of jets aimed at a common collision point, where at least two jet streams collide to create a finely atomized liquid due to kinetic energy dissipated by the impact of the liquid streams. The angle formed by the jets, the pressure applied and the distance at which the jets collide is such that the loss of forward momentum is greater than the energy required to create particles smaller than 5 microns. Liquids injected may include gasoline, diesel-type fuels, or water. The injectors may be employed for port injection or direct injection.

The present disclosure relates to a fuel injector for supplying fuel into a combustion chamber of an internal combustion engine. The fuel injector comprises an injector body, a nozzle, a needle, and a nozzle retainer removably arranged at the injector body to retain the nozzle against the injector body. The nozzle comprises a first channel adapted to contain fuel. The injector body comprises a second channel adapted to contain fuel. The first and second channels are fluidically connected. The needle is slidably arranged in the first and second channels. The needle comprises an upper needle section and a lower needle section. The lower needle section is removably connected to the upper needle section. The present disclosure also relates to a nozzle for a fuel injector, a lower needle section for a fuel injector, and an internal combustion engine comprising a fuel injector.

A fuel injector includes a valve stack forming a seal cavity, and an outlet check extending through the seal cavity. A check seal is positioned within the seal cavity and seals about the outlet check. The valve stack also includes a back-up plate trapping the check seal within the seal cavity, such that a crevice is formed within the seal cavity between the check seal and the back-up plate. The back-up plate has a vent formed therein that fluidly connects the crevice to a drain.

A valve for metering a fluid is described, which is used, in particular, as a fuel injector for internal combustion engines, including an electromagnetic actuator and a valve needle actuatable by the actuator, an armature of the actuator being guided on valve needle, a stop element which limits a movement of the armature relative to the valve needle being situated on the valve needle, and the armature including a spring receptacle which is open toward the stop element and in which a spring supported on the stop element is inserted. The valve needle is guided via the armature and/or the stop element along a longitudinal axis of a housing. Furthermore, as viewed along the longitudinal axis, a length of the spring receptacle is smaller than a spring length of the spring in the non-actuated initial state.

A fuel injector includes a valve stack forming a seal cavity, and an outlet check extending through the seal cavity. A check seal is positioned within the seal cavity and seals about the outlet check. The valve stack also includes a back-up plate trapping the check seal within the seal cavity, such that a crevice is formed within the seal cavity between the check seal and the back-up plate. The back-up plate has a vent formed therein that fluidly connects the crevice to a drain.

A valve for metering fluids, for fuel injection valves for internal combustion engines, includes an electromagnetic actuator in a housing and a valve needle actuatable by an armature of the actuator, which actuates a valve closing body interacting with a valve-seat surface to form a sealing seat. The armature is movably guided on the valve needle. A stop element connected to the valve needle limits, with an actuation of the valve needle, a relative motion between the armature and the valve needle. The stop element includes at least one elastically deformable part and one stop piece, the elastically deformable part being shaped as a sleeve, and the stop element being configured so that the armature, upon the limitation of the relative motion between the armature and the valve needle, initially contacts the elastically deformable part and impacts the stop piece after a corresponding elastic deformation of the elastically deformable part.