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: In order to reduce the size of a tubular rail for a high-pressure fluid, the rail is obtained from a hollow body with an external diameter and an internal diameter, and has two terminal portions, each provided with an external milling to favour gripping thereof. The millings have an external diameter such as to ensure, together with a cylindrical portion of a coaxial element, a radial strength at least equal to that of the hollow body. Made between the hollow body and each cylindrical portion is a front connection. For this purpose, the cylindrical portion has a plane front surface, whilst each terminal portion has an internal milling with an internal diameter greater than the internal diameter of the hollow body so as to house the cylindrical portion and so as to form an annular shoulder. A washer of softer material is set between the annular shoulder and the front surface.

Abstract: The device comprises a connection tube (13) in communication with a hole (11) of a rail (7) for fuel under pressure, the tube (13) being provided with an end swelling (16). The device comprises a first threaded element (18) fixed to the rail (7) in a position corresponding to the hole (11) and a second threaded element (19) designed to engage the first threaded element (18). Removably set between the hole (11) and the swelling (16) is a seal element (21) designed to form a seal both with the hole (11) and with the swelling (16). The seal element (21) is a body of revolution (23) equipped with a passage (25) along a pre-set axis (A), and comprises two end noses (26, 27) designed to be inserted in the swelling (16) and in the hole (11), respectively, and two tapered seal stretches (28, 29).

Abstract: A servo valve (7) for fuel control is provided with an actuator (14) and a valve body (8, 28), which is set in a fixed position and has a stem (33) that extends along a longitudinal axis (3) and defines an internal passage (26); said internal passage (26) has at least two radial channels (39), which give out into an outlet through an outer lateral surface (34) of the stem (33) and have respective first portions (43) of calibrated length and cross section; said first portions (42) are followed by respective second portions of larger diameter; the servo valve (7) is provided with an open/close element (17), which is coupled to the outer lateral surface (34) of the stem (33) substantially in a fluid-tight way and is axially movable under the action of the actuator (14) for opening/closing the internal passage (26) of the stem (33); in the closing position, the open/close element (17) is subject to a zero axial resultant force by the pressure of the fuel.

Abstract: In a gas-supply system for internal-combustion engines, a pressure-reducing valve is arranged 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 an internal chamber for collection of any leakage of gas which is connected to the intake manifold of the internal-combustion engine so as to enable the leaked gas to be discharged in the engine. A solenoid shutoff valve is arranged in the connection to the intake manifold and is opened automatically upon ignition 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 (valve head) 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 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: The injection system has a pump for supplying high-pressure fuel to a storage volume for supplying a number of injectors. The pump has at least one reciprocating pumping element performing a compression stroke synchronously with each fuel injection. The injection system has at least one control device for controlling the amount of fuel supplied by the pump to the storage volume, and which is controlled by a chopper control unit to modulate the fuel volume introduced into the compression chamber during the intake stroke (Ps-Pi). The delivery start instant of the pumping element during the compression stroke being unequivocally defined by the fuel volume introduced.

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). Set on the intake pipe (10) is an on-off solenoid valve (27) having a reduced flow rate substantially of the same order of magnitude as the maximum amount of fuel that can be injected by an injector (5). The solenoid valve (27) is controlled in a chopped way in synchronism with an intermediate part (32) of the suction stroke of each pumping element (18).

Abstract: The injection system (1) comprises a pump (7) designed to send fuel at high pressure to an accumulation volume, for example formed by a common rail (6), for supplying a plurality of injectors (5). The pump (7) comprises at least one pumping element (18) actuated with reciprocating motion with a compression stroke (Pi-Ps) at a sinusoidal speed (24), in synchronism with each step of fuel injection. The injection system (1) comprises at least one by-pass solenoid valve (14), which is controlled by a chopper control unit (16, 28) for modulating the delivery of the pumping element (18) by varying both the instant of start (To) and the instant of end (T1) of delivery during the compression stroke (Pi-Ps), in such a way that the delivery is synchronous with the injection phase.

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: 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 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: 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: 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: A safety valve for pressurized tanks, particularly for tanks for containing methane or LPG for motor vehicles, comprises an open/close element that is kept by elastic means in a closing position, in which it does not enable communication of the internal cavity of the tank with the external atmosphere. When a pre-set maximum value of the pressure inside the tank is exceeded, sufficient for overcoming the load of said elastic means, the open/close element is displaced from its closing position and enables discharge of the gas contained in the tank into the external atmosphere. The elastic means are arranged in series with a fuse element, which is set between the open/close element and the valve body. In this way, whenever the temperature -exceeds a pre-set maximum value, the fuse element melts, causing unloading of said elastic means, which consequently leaves the open/close element free to open.