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: 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: In a system for feeding LPG by injection for an internal combustion engine, sensor means are provided for measuring the electrical current absorbed by the electric motor for driving the feed pump. The operation of said electric motor is interrupted when the measured electrical current absorbed drops below a predetermined threshold value. The system thereby prevents the operation of the motor-pump assembly, which is immersed in the LPG within the LPG tank, when the level of LPG in the tank drops below a minimum admissible value. Simultaneously to the interruption of the operation of the electric motor an auxiliary petrol feed system is activated.

Abstract: A fuel tank for motor vehicles, for example an LPG fuel tank, contains inside it at least one electrical component and has a wall or a plate bearing at least one connector for connection of the electrical component with an electrical line external to the tank. The electrical connector has a body made of synthetic material or of elastomer material directly moulded on one or more conductor pins so as to guarantee hermetic sealing of the tank even in the presence of a pressure jump between the internal cavity of the tank and the external environment. In the case where the body of the connector is made of synthetic material, it bears seats for seal rings made of elastomer material. In the case where it is made of elastomer material, it guarantees directly the function of tightness. In either case, there are provided means for exerting an axial compressive force on the part that performs the tightness function.

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: 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 valve (16) has a ball shutter (18) normally pushed by a helical compression spring (24) to close a delivery conduit (11) of the pump (5). A first end (28) of the spring (24) rests against a shoulder (26) of a fastening member (21) fitted in fluidtight manner to the pump (5); a second end (31) of the spring (24) acts directly on the ball (18); the fastening member (21) has a pin (33) coaxial with the conduit (11) and of such a length as to limit the travel of the ball (18) to a predetermined value; and the second end (31) of the spring (24) has at least one small-diameter turn (34) by which to engage the ball (18).

Abstract: The pump (5) has at least one cylinder (6) in which slides a piston (16) moved positively in the compression direction and elastically in the intake direction. A compression spring (26) is located between the shutter (21) of an intake valve (19) and the piston (16) to push the shutter (21) elastically into a closed position by exerting elastic force varying according to the position of the piston (16). The shutter (21) has a plate (28) cooperating with a seat (22) on the intake valve (19) and moveable parallel to the piston (16); and the compression spring (26) acts on the plate (28) to advance both opening and closing of the intake valve (19).

Abstract: The capacity of a high-pressure pump (6) is regulated by a valve system including a variable-capacity on-off valve (23) and an overpressure valve (31). The overpressure valve has a valve body (33) having a cylindrical wall (35) forming a cavity (34) in which slides a shutter (37) having a lateral wall (51) and an end wall (52). The shutter (37) is pushed into a closed position by a calibrated spring (58). The cylindrical wall (35) has first holes (44) for allowing the passage of enough fuel to lubricate the inside of the pump (6), and second holes (47) for supplying the pump (6) via a supply conduit (68) and for draining any surplus fuel into a recirculating conduit (32). The first holes (44) and the second holes (47) are opened by different displacements of the lateral wall (51) of the shutter (37); and the end wall (52) has a calibrated air vent hole (64).

Abstract: The pump has a body in which at least one cylinder for a piston is fixed by a head having a surface facing a corresponding surface of the body. The head has an intake conduit having an inlet at the surface of the head, and the body has a feed conduit having an outlet located at the surface of the body and at the inlet. Between the surfaces, a first seal is placed about the cylinder, and a second seal about the inlet. The seals are separate and made of elastomeric material. One of the seals is housed inside a circular depression in the seat of the cylinder, so as to engage the lateral surface of the cylinder.

Abstract: The device includes a solenoid valve having a supply conduit communicating with the delivery of the pump, a drain conduit, an electromagnet energizable to control an armature controlling a shutter, and reducing means for reducing disturbance in the delivery pressure of the pump when the electromagnet is energized. The reducing means include a chamber having a predetermined volume and located between the supply conduit and the drain conduit; and a fixed shield having an opening in which slides a small-diameter portion of the stem of the armature. The electromagnet is controlled by an electronic unit via a modulator for modulating the duty cycle of the control pulses, and via a circuit for selecting the frequency of the control pulses on the basis of an estimate of hydraulic disturbances depending on at least one operating parameter.

Abstract: The pump has a body including at least a fuel compression chamber and an actuating chamber enclosing the actuating members of the pump; the on-off valve is defined by an independent operating assembly insertable in fluidtight manner inside a hole in the body; the hole connects an inlet conduit to the actuating chamber and to a feed conduit of the compression chamber; the assembly of the valve has a sleeve in turn having an opening located at the fuel feed conduit and which is closed by a shutter sliding inside the sleeve; the sleeve has two seats for two seals located on opposite sides of the opening; and the feed conduit is straight, and can be formed using a drilling tool through the hole.

Abstract: The valve (16) has a ball shutter (18) normally pushed by a helical compression spring (24) to close a delivery conduit (11) of the pump (5). A first end (28) of the spring (24) rests against a shoulder (26) of a fastening member (21) fitted in fluidtight manner to the pump (5); a second end (31) of the spring (24) acts directly on the ball (18); the fastening member (21) has a pin (33) coaxial with the conduit (11) and of such a length as to limit the travel of the ball (18) to a predetermined value; and the second end (31) of the spring (24) has at least one small-diameter turn (34) by which to engage the ball (18).

Abstract: The pump (5) has at least one cylinder (6) in which slides a piston (16) moved positively in the compression direction and elastically in the intake direction. A compression spring (26) is located between the shutter (21) of an intake valve (19) and the piston (16) to push the shutter (21) elastically into a closed position by exerting elastic force varying according to the position of the piston (16). The shutter (21) has a plate (28) cooperating with a seat (22) on the intake valve (19) and movable parallel to the piston (16); and the compression spring (26) acts on the plate (28) to advance both opening and closing of the intake valve (19).

Abstract: The capacity of a high-pressure pump (6) is regulated by a valve system including a variable-capacity on-off valve (23) and an overpressure valve (31). The overpressure valve has a valve body (33) having a cylindrical wall (35) forming a cavity (34) in which slides a shutter (37) having a lateral wall (51) and an end wall (52). The shutter (37) is pushed into a closed position by a calibrated spring (58). The cylindrical wall (35) has first holes (44) for allowing the passage of enough fuel to lubricate the inside of the pump (6), and second holes (47) for supplying the pump (6) via a supply conduit (68) and for draining any surplus fuel into a recirculating conduit (32). The first holes (44) and the second holes (47) are opened by different displacements of the lateral wall (51) of the shutter (37); and the end wall (52) has a calibrated air vent hole (64).

Abstract: A fuel injection system with controlled injectors for diesel engines includes a system for regulating the temperature of the fuel, including thermostatically-controlled preheating means associated with the fuel supply circuit and electronically-controlled cooling means associated with the fuel recycling circuit.