A fuel injector includes an injector housing, an outlet check, an injection control valve assembly, and a valve seat orifice plate integrating a valve seat and various orifices for outlet check control. In the valve seat orifice plate a drain orifice extends between a valve seat surface and a check control chamber formed between a closing hydraulic surface of the outlet check and the valve seat orifice plate. First and second re-pressurization orifices extend between an outer surface of the valve seat orifice plate and the check control chamber.

A director plate retainer of a fluid injector includes an outer wall which is annular in shape and which extends from an outer wall first end to an outer wall second end and which is centered about an axis. The director plate retainer also includes a lateral wall which is annular in shape and which extends toward the axis from a radially outer extent, which is proximal to the outer wall, to a radially inner extent, which is distal from the outer wall. The director plate retainer also includes an inner wall which is annular in shape and which extends from an inner wall first end, which is proximal to the lateral wall, to an inner wall second end, which is distal from the lateral wall, the inner wall extending along the axis in a direction that is opposite from the outer wall.

An injection hole body has injection holes to inject fuel. A valve body forms a fuel passage with an inner surface of the injection hole body to communicate with inflow ports of the injection holes. The valve body opens and closes the fuel passage by being seated on and unseated from a seating surface of the injection hole body. An inflow port gap distance is a gap between the valve body and the inflow ports along a center axis of the valve body. An inter-injection hole distance is a distance between inflow ports, which are adjacent to each other, among the inflow ports placed around the center axis. The inter-injection hole distance is smaller than the inflow port gap distance in a state where the valve body is unseated from the seating surface and is at a farthest position in its movable range.

A plurality of injection holes include at least one flat injection hole while an outlet opening of the at least one flat injection hole has a long axis and a short axis, and the at least one flat injection hole includes at least one specific flat injection hole. The specific flat injection hole has an injection hole axis that connects between a center of an inlet opening and a center of the outlet opening, and the long axis of the outlet opening is perpendicular to a plane which includes the injection hole axis and is parallel with the valve axis. An inner wall of the outlet opening has two planar portions which are opposed to each other while the long axis is interposed between the planar portions.

An injector for introducing a fluid. The injector has a valve seat in which a multiplicity of injection holes are formed, and a closing element that releases and closes a fluid path to the injection holes, a size of an inlet area of at least two injection holes being different, and a spacing of the injection holes in the circumferential direction to the adjacent injection hole in each case being selected as a function of the size of the inlet areas of the injection holes.

A needle stroke switch and a fuel injector having such a switch, the needle stroke switch including a seat plate having a plate-like main body and a passage connecting the two planar sides of the plate-like main body, an anchor element which can be lifted off from the passage in the seat plate, and a control valve which is arranged on the side of the seat plate opposite the anchor element and is designed to interact with a nozzle needle. The seat plate is electrically isolated from a surrounding injector housing and an electrical connection to the injector housing is possible only via the nozzle needle which interacts with the seat plate. Furthermore, the needle stroke switch is characterised in that at least one ceramic and/or plastic part is provided which contacts the seat plate in order to isolate the seat plate from the surrounding injector housing.

A fuel injector for supplying fuel to a fuel consuming devise includes a fuel inlet for receiving the fuel, a nozzle tip for dispensing the fuel from the fuel injector, a conduit for communicating the fuel from the fuel inlet to the nozzle tip, a valve seat, and a valve selectively seatable and unseatable with the valve seat for selectively preventing and permitting fuel flow out of the nozzle tip. The nozzle tip includes a non-circular recess on a downstream side thereof and a metering hole on an upstream side thereof opening into the non-circular recess to allow fuel to exit the nozzle tip, the metering hole having a smaller area than the non-circular recess.

A fuel injector has a seat and at least one seat passage. The seat includes an outer tip surface through which the seat passage extends. A non-thermally conducting coating is provided on at least a portion of the outer tip surface and not on surfaces defining the seat passage. The coating is constructed and arranged to be heated by combustion gases so that the outer tip surface reaches a temperature greater than a temperature that the outer tip surface would reach if the coating was not provided so as to cause evaporation of fuel that contacts the outer tip surface, The seat passage is constructed and arranged to not be substantially heated by conduction from the outer tip surface and to be cooled by fuel passing there-through so as to prevent deposits of combustion from accumulating on surfaces defining the seat passage.

The invention relates to a fuel injector for internal combustion engines for injecting fuel at high pressure, comprising a pressure chamber formed in an injector body, in which pressure chamber a nozzle needle is arranged in a longitudinally movable manner, which nozzle needle has a cone region tapered in a combustion chamber direction and a pin region having a constant diameter d23 at a combustion-chamber end of the nozzle needle. The injector body has a substantially conical nozzle needle seat, from which a first injection opening extends, and a blind hole, which adjoins the nozzle needle seat on the combustion chamber side. The blind hole has a cylindrical segment, which has the diameter d31, and a hole base, from which a second injection opening extends. The cone region of the nozzle needle interacts with the nozzle needle seat and thereby opens and closes the first injection opening and the second injection opening with respect to the pressure chamber. During a partial stroke of the nozzle needle, the first injection opening and the second injection opening are connected to each other by means of a throttle gap, which is formed in the blind hole between the pin region and the wall of the blind hole, and the throttle gap remains constant at least over the partial stroke of the nozzle needle.

A fuel injector nozzle assembly includes a two-piece outlet check having a timing control piece and a rate control piece. A nozzle passage is formed between a nozzle body and a two-piece outlet check, and a sac cavity is formed by the rate control piece and the nozzle body and fluidly connects a through-hole in the rate control piece to nozzle outlets. A starting-flow clearance is formed by the rate control piece and the timing control piece, and is opened by moving the timing control piece relative to the rate control piece. Moving the rate control piece relative to the nozzle body opens a main-flow seat. The nozzle assembly provides a slow starting injection rate shape in a common rail or similar fuel system and improved controllability over minimum delivery quantities.