A guide hole extending axially, a valve seat and an injection port are coaxially formed on an elongated valve body in this order toward a distal end of the valve body. A pressurized fuel is introduced into a basal end of the guide hole. A valve element is slidably received in the guide hole of the valve body. Inclined passages are formed in one of the valve element and the valve body. When the valve element is lifted, the pressurized fuel flows, as a swirling current, between a valve portion and the valve seat, proceeds toward an exit of the injection port while swirling along an inner peripheral surface of the injection port, and is injected from the injection port. When the valve element is in the fully lifted position, an orifice for restricting an amount of fuel injected from the injection port per unit time is formed between the valve portion and the valve seat.

A swirl injection valve includes: a nozzle body including a hollow cylindrical body having a hole and a bottom portion on which a nozzle port and a valve seat are formed; a needle valve member, slidably inserted and reciprocally moved within the hole of the nozzle body, having a tip portion for seating on the valve seat and controlling the opening and closing of the nozzle port; a swirl chamber formed upstream of the nozzle port and defined between an inner wall of the nozzle body and an outer wall of the needle valve member; a fuel supply passage formed within the nozzle body and connected to a fuel supply source; and inclined passage comprising at least one short passage connected to the swirl chamber and the fuel supply passage and tangentially opened to the swirl chamber at a predetermined inclined angle. The fuel is tangentially supplied from the inclined passage to the swirl chamber without pressure loss. Thus the intense swirling flow of the fuel is formed within the swirl chamber and injected from the nozzle port, thereby stably and efficiently injecting the fuel at a predetermined spray angle into extremely fine particle.

A fuel injection valve for internal combustion engines has a valve body in which a pistonlike valve member is longitudinally displaceably disposed in a bore. The valve member is surrounded, over at least part of its length, by a pressure chamber that can be filled with fuel. On its end toward the combustion chamber, a valve seat is embodied in the bore, on which seat the valve member comes to rest with a valve sealing face in a closing position, so that the pressure chamber is disconnected from at least one injection opening located downstream of the valve sealing face. First and second parallel annular grooves are formed in the end region of the valve member disposed axially toward the valve seat and the valve sealing face is disposed between these two annular grooves.

This invention relates to a mini type fuel injector and in particular to one including a stator provided at the outer surface with a flange dividing the stator into a first portion and a second portion, an adjusting pipe slidably disposed within the hole of the second portion of the stator, a bobbin mounted on the second portion of the stator with its one end bearing against the flange and its the other end extending out of the second portion and wrapped with insulated wires to form a coil, a housing having an inner reduced neck supporting a lower end of the coil and joined together with the stator by rivetting, a socket arranged in the flange of the stator, an armature received between the stator, the bobbin and the housing, a valve body having a flange for connecting the housing by rivetting and a compression spring with two ends thereof urging against the adjusting pipe and the armature, whereby the construction is simplified and the magnetic flux path is reduced thereby speeding up the dynamic response, devaluating the low-end linearity as the providing desirable atomizing effect.

A fuel injection valve includes at least two throttling constrictions. The fuel is guided in so that it flows through one of the throttling constrictions with a flow component directed away from the spray orifice. Thus, at least partially compensating opposing force is exerted on the valve needle or an element (e.g., an armature) with a non-positive connection to the valve needle.