RU2195570C2 - Internal combustion engine fuel injection system - Google Patents

Abstract

FIELD: mechanical engineering; internal combustion engines. SUBSTANCE: invention relates to fuel delivery control systems. Said fuel injection system has air choke mechanically coupled with accelerator pedal and fuel reservoir containing fuel under pressure, electromagnetic fuel valve, fuel meter, all connected by pipeline, engine intake manifold and meter and electromagnetic fuel valve electronic control unit electrically connected with engine crankshaft rotation cycle pickup. According to invention, outlet of electromagnetic fuel valve is connected by pipeline with fuel meter inlet. Electronic control unit is provided with comparator whose outlet is electrically coupled with electromagnetic fuel valve, and signal XI from pickup of fuel pressure at outlet of electromagnetic fuel valve and signal X2 from device evaluating cyclic delivery of fuel, for instance, from pickup of pressure in engine intake manifold, are supplied to two inlets of comparator. EFFECT: increased accuracy of fuel metering by changing pressure at meter inlet depending on change of required fuel rate. 2 cl, 1 dwg

Description

 The invention relates to the field of controlling the supply of fuel to an internal combustion engine (ICE) and can be used in power systems for engines with gas or liquid fuel.

 A known fuel injection system in an internal combustion engine containing an air throttle kinematically connected to an accelerator pedal, as well as a pressure fuel tank, a fuel solenoid valve, a differential gearbox controlled by a discharge in the engine intake manifold, a fuel meter, an electronic metering unit and an electromagnetic a fuel valve electrically connected to the engine crankshaft sensor. As a dispenser, one high-speed solenoid valve of the central or several electromagnetic valves of the distributed fuel injection is used (see published information on the application 97120009, IPC F 02 M 21/02, 10.06.99).

 By its design solution and functional implementation, this system is the closest technical solution to the claimed invention and can be taken as a prototype.

 A disadvantage of the known system is that the differential gearbox, which is controlled by the discharge in the intake manifold of the engine, has an inertia associated with the inertia of the membranes, and the pressure at the outlet of the differential gearbox is somewhat dependent on the pressure in the fuel tank, which introduces significant errors in fuel metering .

 The technical result of the claimed invention is to improve the accuracy of fuel metering by changing the pressure at the inlet of the dispenser depending on the change in the required fuel consumption, for example, depending on the change in vacuum in the intake manifold of the engine.

 The technical result is achieved due to the fact that the fuel injection system in the internal combustion engine contains an air throttle kinematically connected to the accelerator pedal, as well as a pressure fuel tank, a fuel solenoid valve, a fuel meter, an engine intake manifold, an electronic metering control unit and a fuel solenoid valve, electrically connected to the engine rotation sensor, wherein the output of the electromagnetic valve fuel is connected by a pipe to the input of the fuel dispenser, the electronic unit contains a comparison device, for example, a comparator, the output of which is electrically connected to the fuel solenoid valve, and the signal X1 from the fuel pressure sensor at the output of the fuel solenoid valve and signal X2 s devices for evaluating cyclic fuel consumption, for example, from a pressure sensor in the intake manifold of the engine.

 The drawing shows a fuel injection system in an internal combustion engine.

 The fuel injection system in the internal combustion engine contains a pressure fuel tank 1, a fuel solenoid valve 2, a fuel meter 3, an engine intake manifold 4, an air throttle 5, an electronic control unit 6, which includes a comparison device K, for example a comparator, and a forming unit 7 impulses to control the fuel metering device. The pressure fuel tank 1 is connected in series with the fuel solenoid valve 2, the fuel meter 3 and the intake manifold of the engine 4. The pulse generator 7 is electrically connected to the sensor D1 of the engine crankshaft cycles, for example, to the ignition timing sensor. The first input of the comparison device K is electrically connected to the fuel pressure sensor D2 at the output of the fuel solenoid valve, the second input is electrically connected to the device 8 for estimating the cyclic fuel consumption, for example, to the pressure sensor in the intake manifold of the engine. The output of the comparison device K is electrically connected to the fuel solenoid valve 2. The throttle valve 5 is connected by an air duct to the intake manifold of the engine 4.

 The fuel injection system in the internal combustion engine operates as follows.

 In the absence of rotation of the crankshaft of the engine, pulses from the sensor D1 do not arrive at the former 7 and the fuel dispenser 3 is closed, fuel does not enter the engine. When the crankshaft rotates, for example, at start-up, pulses are sent from the D1 sensor to the shaper 7 of the dispenser 3 opening pulses. The X1 signal from the D2 sensor, which characterizes the fuel pressure at the output of the electromagnetic valve 2, is compared by the comparison device K with the signal X2 from the device 8 estimates of cyclic fuel consumption, for example from a pressure sensor in the intake manifold. If X1 is less than X2, the output signal of the fuel solenoid valve 2 appears at the output of the comparison device, from the tank 1, the fuel through the open solenoid valve 2 enters the dispenser input. If X1 is greater than or equal to X2, then there is no signal at the output of the comparison device and the fuel solenoid valve 2 is closed, the fuel pressure proportional to the cyclic fuel consumption is set at the metering inlet. If the throttle valve 5 opens, the pressure in the intake manifold increases, signal X2 increases, the electromagnetic valve 2 opens, and the fuel pressure at the inlet of the dispenser 3 increases.

 Pulses of constant duration, formed by block 7 with each cycle, open the dispenser and provide fuel injection in proportion to its pressure at the inlet of the dispenser. When the throttle is closed, the signal X2 decreases, the electromagnetic valve 2 closes and the fuel pressure at the inlet of the dispenser 3 decreases, the cyclic fuel supply to the engine decreases.

 When using the proposed system, the accuracy of fuel metering increases in comparison with the prototype, since the pressure at the inlet of the dispenser is determined by the pressure sensor and does not depend on the pressure in the fuel tank.

 The speed of the proposed system is also higher than the speed of the prototype, since the response of the comparison device is almost instantaneous, and the inertia of the fuel solenoid valve is less than the inertia of the differential gearbox.

 When converting gasoline vehicles to gas fuel, standard controllers can be used as a fuel consumption estimation device 8, which control the operation of gasoline dispensers (injectors) and take into account information from a large number of sensors, including information about exhaust gases (oxygen sensor). At the same time, the quality of dosing of gas fuel when using the proposed system ensures the fulfillment of requirements similar to the requirements for a car when it is running on gasoline.

Claims (1)

 A fuel injection system in an internal combustion engine comprising an air throttle kinematically connected to an accelerator pedal, as well as a pressurized fuel tank, a fuel solenoid valve, a fuel metering device, an engine intake manifold, an electronic metering control unit and a fuel electromagnetic valve electrically connected with a sensor for rotation cycles of the engine crankshaft, characterized in that the output of the fuel solenoid valve is connected by a pipeline with the input of the fuel dispenser, the electronic unit contains a comparison device, for example, a comparator, the output of which is electrically connected to the fuel solenoid valve, and a signal X1 from the fuel pressure sensor at the output of the fuel solenoid valve and signal X2 from the cyclic flow rate estimator are supplied to two compared inputs of the comparison device fuel, for example from a pressure sensor in the intake manifold of the engine.