A fuel injector is provided. The fuel injector includes a sleeve having a first end proximate an outlet; a piston slidingly received in the sleeve, the piston having a first end proximate the outlet; a pumping chamber at least partially defined by the sleeve between the first end of the piston and the outlet; and a normally-open inlet valve through which fuel passes to enter the pumping chamber.

A fuel injector is provided. The fuel injector includes a sleeve having a first end proximate an outlet; a piston slidingly received in the sleeve, the piston having a first end proximate the outlet; a pumping chamber at least partially defined by the sleeve between the first end of the piston and the outlet; and a normally-open inlet valve through which fuel passes to enter the pumping chamber.

In a droplet ejector equipped with an ejection port for ejecting minute droplets of a liquid, the ejection port 61 or the ejector and a conductor 10 such as a vehicle body are made electrically conductive to increase the electrostatic capacity of the ejection port 61 or the ejector and to suppress enlargement of the potential difference between the ejection port 61 and the liquid caused by flow electrification of the liquid. When the potential difference is large, a coulomb force acts between the electrified droplets and the electrostatically-charged ejection port, causing problems such as delayed or insufficient droplet discharge, but such problems are solved by increasing the electrostatic capacity of the ejection port 61 or the ejector.

In a droplet ejector equipped with an ejection port for ejecting minute droplets of a liquid, the ejection port 61 or the ejector and a conductor 10 such as a vehicle body are made electrically conductive to increase the electrostatic capacity of the ejection port 61 or the ejector and to suppress enlargement of the potential difference between the ejection port 61 and the liquid caused by flow electrification of the liquid. When the potential difference is large, a coulomb force acts between the electrified droplets and the electrostatically-charged ejection port, causing problems such as delayed or insufficient droplet discharge, but such problems are solved by increasing the electrostatic capacity of the ejection port 61 or the ejector.

An object of the present invention is to provide a fuel injection valve that realizes atomization while suppressing spread of a spray. A fuel injection valve includes: a valve body and a valve seat that cooperate to open and close a fuel passage; a swirl imparting chamber that is arranged on a downstream side of an opening and closing portion of the fuel passage by the valve body and the valve seat, and imparts a swirling velocity to fuel; a communication passage arranged on an upstream side of the swirl imparting chamber and connected to the swirl imparting chamber; and fuel injection holes and that are open at a bottom surface of the swirl imparting chamber and injects fuel imparted with the swirling velocity in a swirl passage to an outside, the fuel injection holes and configured such that cross-sectional areas of the fuel injection holes and increase from the inlet to the outlet.

A solenoid valve for a fuel system has an electric coil and an armature disposed in a housing. A preassembled valve unit with valve seat, valve member, valve spring, and armature plate connected captively to each other is provided. In the valve unit, the valve seat is loosely secured between valve member and armature plate. The valve unit is inserted and secured in an open housing end and the valve spring contacts an inner shoulder of the housing. Armature plate and armature form a magnetic circuit. The valve member is supported on the armature plate and switched to open and close an outlet of the valve seat. By suppling current, a magnetic field is generated in the armature and attracts the armature plate into an operative valve position. The valve spring returns the armature plate into a rest position when the coil is currentless.

A solenoid valve for a fuel system has an electric coil and an armature disposed in a housing. A preassembled valve unit with valve seat, valve member, valve spring, and armature plate connected captively to each other is provided. In the valve unit, the valve seat is loosely secured between valve member and armature plate. The valve unit is inserted and secured in an open housing end and the valve spring contacts an inner shoulder of the housing. Armature plate and armature form a magnetic circuit. The valve member is supported on the armature plate and switched to open and close an outlet of the valve seat. By suppling current, a magnetic field is generated in the armature and attracts the armature plate into an operative valve position. The valve spring returns the armature plate into a rest position when the coil is currentless.

A metal valve body having a fuel injection port includes a nozzle plate accommodation part accommodating a nozzle plate of synthetic resin and aligning a center of the nozzle plate with a central axis of the valve body. A front end surface abutting against the nozzle plate is accommodated in the nozzle plate accommodation part. A swage projection fixes the nozzle plate to the front end side on which the fuel injection port is formed. The nozzle plate is swage-fixed in the state in which a spring action part is elastically deformed on the front end side of the valve body by the swage projection, and a nozzle hole formation part is constantly pushed against the front end surface of the valve body by the elastic force of the spring action part.

A metal valve body having a fuel injection port includes a nozzle plate accommodation part accommodating a nozzle plate of synthetic resin and aligning a center of the nozzle plate with a central axis of the valve body. A front end surface abutting against the nozzle plate is accommodated in the nozzle plate accommodation part. A swage projection fixes the nozzle plate to the front end side on which the fuel injection port is formed. The nozzle plate is swage-fixed in the state in which a spring action part is elastically deformed on the front end side of the valve body by the swage projection, and a nozzle hole formation part is constantly pushed against the front end surface of the valve body by the elastic force of the spring action part.

A fuel injection device comprising electricity-generating means generating electricity by rotation of an engine and outputting a predetermined signal, and a solenoid valve injecting fuel; the valve being opened as a result of a drive current applied to a coil, and the fuel being injected into an intake passage of the engine at a predetermined timing during the rotation of the engine; to ensure that the flow rate required during high-speed operation ca be adequately provided in a fuel injection device for injecting/supplying fuel to an engine. The electricity-generating means is an alternating current generation means attached to the engine in a crank angle position at which an output is generated in synchronization with the intake timing of the engine; the signal is an injection command signal applied to the solenoid valve as an alternating-current drive current; and the applied voltage increases with increased engine speed.