| Patent application number | Description | Published |
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| 20090032621 | METERING SERVOVALVE AND FUEL INJECTOR FOR AN INTERNAL COMBUSTION ENGINE - A fuel injector and servovalve for an internal combustion engine. In one embodiment, the fuel injector comprises a casing; a balanced metering servovalve in the casing that controls movement of an injection control rod along an axial cavity; said servovalve having; a valve body comprising a control chamber; an axial stem comprising a discharge channel having at least one radial segment that runs to a lateral surface of said axial stem; a calibrated inlet passage in communication with said control chamber; and an outlet passage in communication with said control chamber and the discharge channel; a sleeve having a shutter, said axial stem extending into said sleeve in a fluid tight manner and so that said sleeve that can axially slide along said axial stem between a closed position and an open position of said at least one radial segment, thereby controlling said movement of said injection control rod along said axial cavity; an electro-actuator having an armature that controls said axial sliding of said sleeve along said axial stem; an elastic member that exerts a force upon said armature that maintains said sleeve in said closed position, said electro-actuator being able to control said armature to overcome said force of said elastic member; and said armature being separate from said sleeve. | 02-05-2009 |
| 20090050110 | ACCUMULATION-VOLUME FUEL INJECTION SYSTEM FOR AN INTERNAL-COMBUSTION ENGINE - The injection system comprises a pump designed to send fuel at high pressure to an accumulation volume, for example formed by a common rail, for supplying a plurality of injectors. The pump comprises at least one pumping element actuated with reciprocating motion with a compression stroke at a sinusoidal speed, in synchronism with each step of fuel injection. The injection system comprises at least one by-pass solenoid valve, which is controlled by a chopper control unit for modulating the delivery of the pumping element by varying both the instant of start and the instant of end of delivery during the compression stroke, in such a way that the delivery is synchronous with the injection phase. | 02-26-2009 |
| 20090320800 | FUEL INJECTOR WITH BALANCED METERING SERVOVALVE FOR AN INTERNAL-COMBUSTION ENGINE - The injector comprises a balanced metering servovalve for controlling a rod for opening/closing a nebulizer. The servovalve has a valve body having a control chamber provided with an outlet passage that is opened/closed by an axially mobile open/close element. The open/close element is made of a single piece with a bushing separate from an armature plate of an electromagnet. The bushing is coupled to a stem in an axially slidable way for closing an exhaust duct in communication with the outlet passage The open/close element is kept in a closed position by a spring that acts upon the bushing through an intermediate body connected thereto. The armature plate can be displaced with respect to the bushing between a flange of the intermediate body and a shoulder of the bushing, for eliminating the rebounds of the open/close element upon closing of the servovalve. | 12-31-2009 |
| 20100162992 | FUEL INJECTION SYSTEM WITH HIGH REPEATABILITY AND STABILITY OF OPERATION FOR AN INTERNAL-COMBUSTION ENGINE - The system comprises an injector controlled by commands of a control unit. The injector comprises a dosing servo valve having a control chamber provided with an outlet passage that is opened/closed by an open/close element that is axially movable. The open/close element is carried by an axial guide element that is separate from an anchor of an electromagnet. The open/close element is held in the closing position by a spring acting through an intermediate body. Preferably, the strokes of the open/close element and of the anchor are chosen so as to eliminate, upon closing of the solenoid valve, the rebounds of the open/close element subsequent to the first rebound. The control unit controls an injection comprising a pre-injection and a main injection, via two distinct electrical commands, which are spaced apart by a dwell time such as to occur in an area of reduced variation of the amount of injected fuel; therefore, the stability of operation of the system increases as said dwell time varies. | 07-01-2010 |
