Abstract: A fuel-injection system (1, 1?, 1?, 1??) for an internal-combustion engine (2), of the type provided with compressor mechanism (4) for making available the fuel at a high pressure to an storage volume (7), and a plurality of injectors (8, 8?, 8??) fluidically connected to the storage volume (7) for taking in the fuel from the storage volume (7) and injecting it into respective combustion chambers (12) of the engine (2). The storage volume (7) is advantageously split into a plurality of distinct elementary storage volumes (9, 9?, 9a, 9b) fluidically connected to one another.

Abstract: A fuel injector for an internal-combustion engine comprises an injector body and an injection-control valve, which in turn comprises: an open/close element; an elastic thrust element for pushing the open/close element; and a solenoid actuator, which can be actuated for exerting an action countering the thrust exerted by the elastic element. The solenoid actuator is formed by a monolithic assembly obtained in a mould, in which there is injected, on a core and a coil coupled to one another, a plastic material, which defines, once it has solidified, a body for insulation of the core from the injector body and which forms, once it has solidified, a monolithic assembly with the core and the coil.

Abstract: A fuel-injection system (1, 1?, 1?, 1??) for an internal-combustion engine (2), of the type provided with: a tank (3) for collection of the fuel; compressor system (4) for drawing in the fuel from the tank (3) and making it available at high pressure to an storage volume (7); at least one injector (8, 8?, 8??) hydraulically connected to the storage volume (7) for taking in the fuel at a high pressure from the storage volume (7) and injecting it into a respective combustion chamber (12) of the engine (2); a fluid line (17) connecting the storage volume to the tank; and pressure-regulator means (19) in the storage volume (7) set along the fluid line (17); the pressure-regulator systems (19) are set hydraulically downstream of the storage volume (7) so as to enable a continuous flow of fuel through the storage volume (7) itself.

Abstract: The injection system (1) includes a storage volume (6) of pressurized fuel supplied by a high-pressure pump (7) along a delivery pipe (8); and a control unit (16) for defining the required fuel pressure of the storage volume (6) as a function of the operating conditions of the engine (2). The regulating device includes a bypass solenoid valve (14); and a pair of non-return valves (32, 33) connected antiparallel and located between the bypass valve (14) and the storage volume (6). One of the non-return valves (32, 33) permits fuel drainage from the storage volume (6) to the bypass valve (14) when the control unit (16) defines a predetermined reduction (?p) in the fuel pressure of the storage volume (6).

Abstract: The injection system (1) includes a pump (7) for supplying high-pressure fuel to a storage volume, defined for example by a common rail (6), for supplying a number of injectors (5). The pump (7) has at least one reciprocating pumping member (18) with a sinusoidal compression stroke (24). The injection system (1) includes at least one bypass solenoid valve (14) controlled by a control unit (16) having a chopper unit (28) for producing multiple deliveries (29, 31) at each compression stroke (24), so that the pressure in the common rail (6) is substantially level. Each pumping member (18) may be associated with a corresponding bypass solenoid valve (14).

Abstract: The high-pressure pump (7) comprises a number of pumping elements (18) actuated in reciprocating motion through corresponding suction and delivery strokes. Each pumping element (18) is provided with a corresponding intake valve (25), in communication with an intake pipe (10), supplied by a low-pressure pump (9). Arranged on the intake pipe (10) is a shut-off valve (27) controlled in a choppered way in synchronism with an initial part (32; 32?) of the suction stroke of each pumping element (18).

Abstract: A control servo valve (8) is housed inside the casing of an internal combustion engine fuel injector (1), and has an actuator (9), a control chamber (13) communicating with a fuel inlet (5) and with a fuel outlet passage (22), and a shutter (35) movable along an axis (3) by the actuator (9) between a closed position and an open position to close and open the outlet passage (22) respectively; the servo valve (8) also has a fixed axial rod (29) interposed between the actuator (9) and the control chamber (13); the outlet passage (22) comes out through an outer lateral surface (30) of the axial rod (29); and the shutter (35) is defined by a sleeve which slides axially on the outer lateral surface (30), and, in the closed position, closes the outlet passage (22) so as to be subjected to a zero axial resultant force by the pressure of the fuel.

Abstract: A control servo valve (8) is housed inside the casing (2) of an internal combustion engine fuel injector (1), and has a piezoelectric actuator (40), and a control chamber (13) having a fuel outlet passage (21); the outlet passage (21) comes out inside an annular chamber (34) defined by a fixed tubular portion (25) and by a shutter (32), which engages the tubular portion (25) in substantially fluidtight manner and is slid axially by the piezoelectric actuator (40) from a closed position, in which it closes the annular chamber (34) and is subjected to a zero axial resultant force by the fuel pressure, to an open position, in which the outlet passage (21) communicates with a discharge conduit.

Abstract: A system for controlling filling a motor-vehicle tank with LPG, comprises: a normally-closed valve, which can be driven in opening by excitation of a solenoid; sensor means, pre-arranged to emit an electrical signal indicating that a pre-set maximum level of LPG in the tank has been reached; and a control member, which can be operated manually for generating an electrical signal indicating the intention to proceed with filling the tank. The system further comprises a control circuit, which is independent of the circuit on board the motor vehicle and which is active even when the vehicle engine is turned off and is pre-arranged for exciting the solenoid of the valve in order to control opening thereof when it receives the aforesaid signal indicating activation of the mode of filling of the tank, and for de-exciting the aforesaid solenoid in order to control closing of the valve when the signal indicating that the pre-set maximum level of LPG in the tank has been reached is received.

Abstract: In a gas-supply system for internal-combustion engines, a pressure-reducing valve is set between the reservoir of the gas and a distribution manifold or rail that feeds the gas to a series of electromagnetically controlled injectors associated to the various cylinders of the engine. The pressure-reducing valve has a piston member, which is mobile inside the valve body, for controlling said open/close element, and has one end facing a first chamber within said valve body, set in the path of connection of the inlet connector with the outlet connector, and the opposite end facing a second chamber within said valve body. The aforesaid second chamber is connected to the intake manifold of the internal-combustion engine so as to enable any flow of gas that has leaked from said first chamber to said second chamber to be discharged in the engine.

Abstract: In a gas-supply system for internal-combustion engines, a pressure-reducing valve is set between the reservoir of the gas and a distribution manifold or rail that feeds the gas to a series of electromagnetically controlled injectors associated to the various cylinders of the engine. The reduced pressure supplied by the pressure-reducing valve is further reduced via a pressure-regulating solenoid valve, to an extent that depends upon the supply current of its solenoid. The electrical supply to the solenoid of said solenoid valve is controlled by an electronic control unit according to the signal issued by a sensor of the pressure in the rail and according to stored maps, which supply the optimal pressure value for each operating condition of the engine.

Abstract: In a gas-supply system for internal-combustion engines, a pressure-reducing valve is set between the reservoir of the gas and a distribution manifold or rail that feeds the gas to a series of electromagnetically controlled injectors associated to the various cylinders of the engine. The pressure-reducing valve brings about a pressure drop which depends upon a pilot-pressure signal that is sent thereto by a pilot solenoid valve. The electrical supply to the solenoid of said pilot solenoid valve is controlled by an electronic control unit according to the signal issued by a sensor of the pressure in the rail for the purpose of regulating the pressure in the rail at a desired level, according to the operating conditions of the engine.

Abstract: In a gas-supply system for internal-combustion engines, a pressure-reducing valve is set between the reservoir of the gas and a distribution manifold or rail that feeds the gas to a series of electromagnetically controlled injectors associated to the various cylinders of the engine. The pressure-reducing valve has a piston member that faces a chamber set downstream of a restricted passage defined inside the body of the valve in communication between the inlet connector and the outlet connector. The piston member is pushed by thrust means towards a position in which it causes opening of an open/close element that controls the communication between said restricted passage and the inlet connector. The piston member is preferably provided with a single seal gasket that prevents leakage of gas towards the outside through the sliding coupling of the piston member within the respective guide bushing.

Abstract: In a tank for liquid fuel, particularly a tank for LPG in a system for supply of LPG to the internal-combustion engine of a motor vehicle, the level-sensor device comprises a floating member guided so as to move in a substantially vertical direction within the tank according to the variations of level, and transducer means consisting of an aligned series of reed relays that are activated selectively by one or more permanent magnets carried by the floating member.

Abstract: The fitting has a high-pressure fuel supply conduit, and the injector has a hollow body having a threaded seat engaged by a threaded portion of the fitting. The fitting has a shoulder located between the threaded portion and another portion of the fitting, and the hollow body has a shoulder on a non-recessed outer surface of the hollow body. The two shoulders are precision machined so they are parallel in use; and the usual high-pressure fuel sealing washer is inserted between the two shoulders so machined. More specifically, the shoulder of the fitting has a groove housing the washer, and the shoulder of the hollow body undergoes circular spot facing to form a series of circular cavities concentric with the axis of the threaded seat and characteristic of Ra=1.6 surface roughness.

Abstract: The invention describes an injector device specifically designed for the injection of an alternative fuel such as LPG, methane, hydrogen or others, in an internal combustion engine. In the injector device, the shutter ensuring sealing in closing condition is separated with respect to the metering means with gauged hole, which perform the function of metering fuel during injection, and it is arranged downstream from said metering means. The shutter is controlled by a solenoid, which is again arranged on the downstream side with respect to said metering means.

Abstract: The injector has an injector body having a seat for a metering valve in turn having a control chamber for controlling a control rod. The control chamber has an inlet conduit and a drain conduit controlled by a shutter, and is defined by two parts, one of which is defined by a bush having a through opening for guiding the control rod, and the other of which is defined by a plug member for closing the control chamber. The inlet conduit is located on the bush, and the drain conduit on the plug member. The bush is of such a diameter as to interfere slightly with at least one cylindrical portion of the seat, and is driven in fluidtight manner inside the seat so that an end edge rests on a shoulder of the seat. The plug member is fixed in fluidtight manner to the opposite end of the bush by means of a ring nut having a projection which acts along the centerline of the thickness of the bush.

Abstract: An LPG fuel tank for motor vehicles is provided, inside, with a support, on which there can be installed in a rapid way a pump assembly including a supply pump and the corresponding electric actuating motor. Preferably, the support is also used for installing a level-sensor assembly within the tank.

Abstract: A method of producing fuel injectors for internal combustion engines provides for establishing a working life of each injector conforming with the working life of the internal combustion engine on which it is installed. Each injector has an injector body having a seat; a valve body housed inside the seat so as to form an annular chamber, for receiving high-pressure fuel, and a gap communicating with the annular chamber; and a seal housed inside the annular chamber to seal the gap. The seal is sized as a function of the permanent deformation to which the seal is subjected during use of the injector, so as to achieve a working life of the injector substantially equal to the working life of the engine.

Abstract: A fuel injector has an injector body extending along a given axis; a tubular valve body housed inside a hole in the injector body and coaxial with the injector body; and an annular chamber defined by the injector body and the valve body. The method of producing the injector includes connecting the valve body to the injector body, and fixing the valve body in a given position along the axis with respect to the injector body by means of a driving operation to interference fit the valve body inside the hole in the injector body.