JPH05500099A - Internal combustion engine fuel supply system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Internal combustion engine fuel supply system Conventional technology The present invention provides an internal combustion engine with an electric fuel pump, a fuel pressure regulator and a fuel metering device. Regarding Seki's fuel supply system.

From DE-053608522 two separate pressure regulators as well as a side pressure regulator and associated with associated control valves, each with a second pressure regulator according to the operating range of the internal combustion engine. A combustion engine designed to reduce or increase fuel pressure by operating BACKGROUND ART Food metering devices are known.

Furthermore, the beginning of the specification of DE-053608522 describes a specially constructed pressure regulator. A fuel injector with a moderator is described. This device uses an electromagnet to generate an additional spring. are engaged, thereby making it possible to control the fuel pressure according to the operating range of the internal combustion engine, respectively. It is made into Noh.

From DE-051576482, fuel is detected by a temperature sensing element connected to the fuel pipe. As the temperature rises, it is possible to increase the pressure in the branch vibe leading to the injection valve. A fuel injection device is known (Claim No. 1 of DE-051576482). section).

An electromagnetic fuel pump is disclosed. In that case, the air flow rate of the intake pipe, the rotation speed, Signals regarding intake manifold pressure, water temperature and battery voltage are processed in the control unit and The controller controls the fuel pump with or without a series resistor. Ru. This results in higher fuel requirements depending on the operating parameters of the internal combustion engine. Sometimes the feed output is increased, and when fuel demand is small, the feed output is adjusted accordingly. and are decreasing.

Furthermore, US-PS3822677 has various fuel pumps depending on the fuel requirement. A fuel pump control device with variable energy supply is shown.

Known devices do not allow optimal results to be achieved in all operating conditions of the internal combustion engine. It became clear. Therefore, it is an object of the present invention to provide a highly flexible device. That's true.

This object is achieved by a combination of the features of the main claim.

Advantages of invention The fuel supply device for an internal combustion engine according to the present invention allows each internal combustion engine to be supplied with relatively simple means. It becomes possible to supply different amounts of fuel with different fuel pressures under different operating conditions. that In addition to the efficient and demand-based fuel delivery provided by the fuel pump, the system also provides ideal pressure characteristics. This also ensures optimum fuel supply even when the internal combustion engine is warm, especially during start-up. Guaranteed.

drawing Embodiments of the invention are shown in the drawings and will be explained in detail below.

FIG. 1 is a schematic diagram of a fuel supply system, and FIG. 2 shows a conventional method and a fuel supply system according to the present invention. FIG. 3 shows the characteristic curve of the pressure regulator based on the method according to This is a supplementary circuit for the fuel pressure regulator.

Description of examples FIG. 1 shows a schematic configuration of a fuel supply system for an external ignition internal combustion engine. . The internal combustion engine itself is shown at 10, the intake pipe at 11, and the exhaust pipe at 12. . The intake pipe 11 is operated by an air flow meter 13 and an accelerator pedal 15. A throttle valve 14 is provided. 16 indicates a rotation speed sensor. electronic control unit The position 20 receives signals from the air flow meter 13, the rotation speed sensor 16, and as the case may be. receives signals from other sensors and controls the fuel pump 23 as well as at least one injector. A signal is output to the injection valve 24. In that case, the fuel pump 23 pumps the fuel from the fuel tank 21. is supplied with fuel and delivers it to the injection valve 24. Pressure regulation downstream of fuel pump 23 25 serves to maintain the fuel pressure at a desired value. The fuel pump 23 sends The supplied amount of fuel in excess of the requested amount is returned to the tank 21 via the reflux pipe.

The configuration of the fuel supply device shown in FIG. 1 basically corresponds to a conventional device.

Importantly, according to the invention, if the demand increases, the fuel quantity also increases. and at the desired pressure in each individual case. Control according to the pump demand is combined with a specific pressure regulator characteristic curve That's true.

FIG. 2 shows the characteristic curves of two pressure regulators.

In that case, the characteristic curve of FIG. 2a corresponds to that of the prior art.

The pressure characteristics are plotted with respect to the fuel quantity. In that case, the pressure regulator of the prior art The characteristic curve is maintained at a predetermined set value PKsall above the minimum fuel flow rate Qwin. It has a characteristic that allows it to be maintained.

On the other hand, Figure 2b shows that the pressure value is almost constant between the minimum and maximum reflux amount. If the reflux amount exceeds Q rnax, the fuel pressure is increased. The characteristic curve of the force regulator is illustrated. Increased pressure values reduce air bubbles during warm start. used to reduce the formation of

Fuel pump controlled according to demand and pressure regulation modified with respect to prior art It is possible to achieve a favorable increase in fuel pressure at a given operating point through the cooperation of the characteristic curves of the I can do it.

It is preferable to increase the fuel pressure not only during starting but also during restart, especially during warm starts. Delicious. This also applies during acceleration.

Controlling the fuel pump according to demand is preferably known from the prior art. This is done using a switching drive. Using this, during normal operation, reflux The amount is controlled so as not to go outside the area determined by Qwin and Qwax.

The configuration of the fuel pressure regulator to obtain the desired pressure characteristics is not particularly problematic for those skilled in the art. do not have. The area where the pressure is kept constant does not need to be very wide, so the pressure regulator The configuration will be simple. In particular, the fuel pressure regulator The fuel pressure is increased. This affects the individual components of the pressure regulator, especially the pressure The spring in the force regulator should be designed accordingly or the return pipe should be This is done through the shape of

FIG. 3 shows a squeezable reflux pipe from the pressure regulator 25 to the tank 21. has been done. In that case, a throttle 26 with a valve 27 connected in parallel is installed on the reflux vibe itself. This valve 27 is electromagnetically driven by the control device 20 of FIG.

This is a variant of the reflux vibrator and fuel known per se as prior art. It is possible to ideally combine controls according to the required amount of the pump, and it can be used in all operating conditions. This allows optimal fuel supply to the internal combustion engine.

FI6.1 abstract Fuel supply for internal combustion engines with electric fuel pump, fuel pressure regulator and fuel metering device A feeding device has been proposed. In that case, the fuel pump delivery output becomes an operating parameter. Therefore, the characteristic curve of the pressure regulator is controlled and the fuel pressure responds to the change in delivery output. Adjusted using lines.

international search report +mfiaIIeeal^oakum-Ha, PCT/DE 91.10031 5 International Search Report

Claims (1)

[Claims] 1) Combustion of internal combustion engines with electric fuel pump, fuel pressure regulator and fuel metering device In the fuel supply system, the delivery output of the fuel pump is controlled according to operating parameters. , the fuel pressure increases due to the corresponding characteristic curve of the pressure regulator in relation to the change in the reflux amount. A fuel supply device for an internal combustion engine, characterized in that it can be set to a certain value. 2) The output of the fuel pump can be switched at least between normal output and peak output. The fuel supply device according to claim 1, characterized in that: 3) The method according to claim 2, characterized in that the peak output is obtained during a cold start. Fuel supply system on board. 4) The device according to claim 2, characterized in that the peak output is obtained at instantaneous starting. Fuel supply system on board. 5) Claim 2, characterized in that the peak output is obtained at the time of starting and at restarting. The fuel supply device described in section. 6) Claim 2, characterized in that the peak output is obtained at a desired acceleration time. The fuel supply device described. 7) Claim 1, wherein the fuel pump is driven by switching. 6. The fuel supply device according to any one of items 1 to 6. 8) The fuel pressure regulator is configured to increase the fuel pressure as the reflux amount increases. According to any one of claims 1 to 7, characterized in that fuel supply system. 9) By making the return pipe of the fuel pressure regulator constrictable, the fuel pressure can be increased. Any one of claims 1 to 8, characterized in that the value is set to a value that is The fuel supply device according to item 1.