摘要:
A fuel injector provided with: an injection valve comprising an injection nozzle; a mobile needle for regulating the fuel flow through the injection valve and ending with a shutting head, which engages a valve seat of the injection valve, is arranged externally with respect to injection valve and presents a predetermined sealing diameter; an actuator for displacing the needle between a closing position and an opening position of the injection valve; a closing spring which tends to maintain the needle in the closing position of the injection valve pushing the shutting head against the valve seat itself in a sense contrary to the feeding sense of the fuel; and a supporting body having a tubular shape and presenting a feeding channel within which a needle is arranged; the needle, at an opposite end of the shutting head, is coupled to a balancing channel, which is at ambient pressure.
摘要:
A method of manufacturing and controlling a butterfly valve for an internal combustion engine; the manufacturing and control method includes the steps of: establishing a maximum gaseous flow rate value which may flow through the feeding pipe when the butterfly plate is in the closing position; determining a conventional closing position at which the gaseous flow rate which flows through the feeding pipe is essentially equal to the maximum gaseous flow rate value; driving an actuator device so as not to normally pass the conventional closing position; and dimensioning the position of a catch element, so that when a rotational shaft abuts against the catch element the gaseous flow rate which flows through the feeding pipe is essentially lower than the maximum gaseous flow rate value.
摘要:
A hydraulic circuit of a servo-assisted mechanical transmission, which is provided with a number of hydraulic actuators provided with corresponding actuation chambers adapted to be filled with pressurized oil; the hydraulic circuit is provided with: a number of solenoid valves, each of which is coupled to a corresponding actuation chamber of a hydraulic actuator; a tank, which contains the oil at atmospheric pressure and is provided with an upper loading aperture; the cap, which closes the loading aperture of the tank and is provided with a through venting hole which puts the tank into communication with the external environment; a filtering element, which is coupled to the cap and is arranged under the venting hole; a hydraulic accumulator containing the pressurized oil; and an electric pump which draws from the tank and feeds the hydraulic accumulator.
摘要:
A method and a plant for filling a hydraulic circuit with a control fluid, in which a vacuum is generated within the hydraulic circuit, the control fluid is supplied to a degasification chamber, a vacuum is generated in the degasification chamber containing the control fluid and the control fluid is supplied under pressure from the degasification chamber to the hydraulic circuit while continuing to maintain the vacuum in the hydraulic circuit.
摘要:
A control method for an internal combustion engine supercharged by means of a turbocharger provided with a turbine and with a compressor; the control method contemplates the steps of: establishing at least one operating limit curve on a Reduced Mass Flow Rate/Compression Ratio map; establishing at least one intervention curve of a wastegate valve which adjusts a bypass pipe of the turbine on a Reduced Mass Flow Rate/Compression Ratio map; establishing at least one intervention curve of a Poff valve which adjusts a bypass pipe of the compressor on a Reduced Mass Flow Rate/Compression Ratio map; using the operating limit curve to limit the pressure target downstream of the compressor used by the engine control; controlling the opening of the wastegate valve if the intervention curve of the wastegate valve is exceeded; and controlling the opening of the Poff valve if the intervention curve of the Poff valve is exceeded.
摘要:
A method for controlling a power assisted propulsion system in a motor vehicle so as to perform a transition from a lower gear to a higher gear without interrupting a driving torque applied to driving wheels; the propulsion system displays an internal combustion engine provided with a drive shaft and a power assisted transmission including: a power assisted mechanical gearbox provided with a primary shaft connectable to the drive shaft and a secondary shaft coupled to a transmission shaft which transmits motion to the driving wheels; a power assisted clutch interposed between the drive shaft and the primary shaft of the gearbox to couple and decouple the drive shaft to the primary shaft of the gearbox; a power assisted brake; and an epicycloidal gear having three rotating elements: a first rotating element coupled to the drive shaft, a second rotating element coupled to the secondary shaft of the gearbox, and a third rotating element coupled to the brake.
摘要:
A control method of a direct injection system of the common-rail type provided with a shut-off valve for controlling the flow rate of a high-pressure fuel pump; the control method contemplates the steps of: feeding the pressurized fuel to a common rail by means of a high-pressure pump which receives the fuel through a shut-off valve; cyclically controlling the opening and closing of the shut-off valve for choking the flow rate of fuel taken in by the high-pressure pump; adjusting the flow rate of fuel taken in by the high-pressure pump by varying the ratio between the duration of the opening time and the duration of the closing time of the shut-off valve; determining a lower limit value of the opening time of the shut-off valve; and adjusting the driving frequency of the shut-off valve so that the real opening time of the shut-off valve is always over the lower limit value.
摘要:
An electromagnetic valve for the dosage of fuel in an internal combustion engine; the electromagnetic valve is provided with: a cylindrical tubular valve body; an obturator, which is arranged within the tubular valve body and is mobile between an open position and a closed position; and an electromagnetic actuator to shift the obturator and comprising a coil arranged outside the tubular valve body, a fixed magnetic pole is arranged within the tubular valve body, a mobile keeper arranged within the tubular valve body, mechanically connected to the obturator and is adapted to be magnetically attracted by the magnetic pole when the coil is excited, a tubular magnetic armature arranged outside the tubular valve body around the coil, and a magnetic washer having an annular shape arranged above the coil between the tubular valve body and the tubular magnetic armature to guide the closing of the magnetic flow around the coil.
摘要:
Described herein is an electronic-injection fuel-supply system for an internal-combustion engine having at least one injector and a fuel pump; the fuel pump is provided with: a variable-volume pumping chamber; a one-way intake valve; a one-way delivery valve; a mobile piston that integrates within it the intake valve and is coupled to the pumping chamber to vary cyclically the volume of the pumping chamber itself; and an actuator device that impresses a reciprocating motion on the piston and has an electromagnetic actuator for actuating the piston during an intake phase and a spring for actuating the piston during a delivery phase.
摘要:
A control method of a direct injection system of the common rail in an internal combustion engine; the control method contemplates the steps of: feeding the pressurized fuel to a common rail by means of a high-pressure pump presenting at least one pumping element mechanically operated by a drive shaft of the internal combustion engine; measuring the angular position of the drive shaft; measuring the fuel pressure in the common rail; analyzing the oscillations of the fuel pressure in the common rail; and determining the phase of the pumping element of the high-pressure pump with respect to the drive shaft according to the oscillations of the fuel pressure in the common rail.