JPH11315768A - Fuel supply system of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a fuel supply system of an internal combustion engine which drives a fuel pump at the required minimum, corrects the drive amount of an injector based on fuel pressure, and realizes an improvement in fuel efficiency and cost reduction. SOLUTION: The fuel supply system of an internal combustion engine is provided with a fuel pump 3A which is located in a fuel tank 1 and which sends fuel to a fuel pipe 2, an injector J which is located in a delivery pipe 4 of the output end of the fuel pipe 2 to inject fuel into the internal combustion engine E, various kinds of sensors 5 to detect the operating state D of the internal combustion engine, fuel pressure detection means to detect the fuel pressure within the delivery pipe, and control means 8A to calculate the control quantity of the injector and fuel pump in accordance with the operating state and fuel pressure. This control means 8A calculates the drive current of the fuel pump 3A in accordance with the fuel quantity based on the target control quantity of the injector J, while correcting the injection time of the injector J in accordance with the fuel pressure, and injects the required amount of fuel from the injector J.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel supply system for an internal combustion engine which controls the drive amount of a fuel pump and an injector to adjust the fuel supply amount. The present invention relates to a fuel supply device for an internal combustion engine that achieves improved fuel efficiency and reduced costs by correcting the amount of drive of an injector based on the above.

[0002]

2. Description of the Related Art FIG. 8 is a schematic diagram showing a conventional fuel supply system for an internal combustion engine. In FIG. 8, E is an engine (internal combustion engine) that generates rotational torque by burning fuel, 1 is a fuel tank filled with fuel of the engine E,
Reference numeral 2 denotes a fuel pipe which constitutes a flow path from the fuel tank 1 to the engine E.

Reference numeral 3 denotes a fuel pump disposed in the fuel tank 1 for sending out fuel to the fuel pipe 2. Reference numeral RG denotes a pressure pump which is disposed in the fuel tank 1 together with the fuel pump 3 to keep the fuel supply pressure constant. The regulator 4 is a delivery pipe disposed at the output end of the fuel pipe 2, and J is an injector disposed on the delivery pipe 4 for injecting fuel into the engine E.

[0004] Reference numeral 5 denotes various sensors for detecting the operating state D of the engine E, and includes a well-known crank angle sensor, a temperature sensor, an air-fuel ratio sensor, and the like. 6 is engine E
Is an intake pressure sensor that detects the intake pressure Pa of the sensor, and can be included in the various sensors 5.

The intake pressure sensor 6 is, for example, an engine E
Can also function as an atmospheric pressure sensor that detects the atmospheric pressure Po when the engine E is stopped.

Reference numeral 8 denotes an ECU comprising a microcomputer for controlling the engine E. For example, the ECU 8 calculates a control amount (injection time) of the injector J in accordance with the intake pressure Pa and other operating states D, and based on the control amount. To drive the injector J to inject a required amount of fuel from the injector J into the engine E.

Next, a general operation of the conventional fuel supply device for an internal combustion engine shown in FIG. 8 will be described. First,
The fuel in the fuel tank 1 is sucked up by the fuel pump 3, sent out to the fuel pipe 2 by the pressure regulator RG in the fuel tank 1 at a constant pressure with respect to the pressure in the fuel tank 1, and delivered through the fuel pipe 2. It is supplied to the pipe 4.

The ECU 8 uses the operating state D detected by the various sensors 5 and the intake pressure Pa and the atmospheric pressure Po detected by the intake pressure sensor 6 to determine the injection time T of the injector J.
j is calculated, and the injector J is driven by the injection time Tj to inject fuel into the engine E.

Specifically, for example, the fuel pressure P in the delivery pipe 4 is determined using the atmospheric pressure Po and the intake pressure Pa.
The differential pressure ΔP between the pressure j and the intake pressure Pa is estimated and calculated, and the injection time Tj of the injector J is calculated and determined using the differential pressure ΔP and another operating state D.

FIG. 9 is a flowchart showing the calculation operation of the ECU 8, and shows an example of a calculation logic of the injection time Tj of the injector J according to the required fuel amount of the engine E. In FIG. 9, the ECU 8 first calculates a basic injection time Tjo of the injector J (step S2).
0).

At this time, the basic injection time Tjo [mse
c] is the intake pressure Pa [Pa], the discharge amount FQ [mcc] of the injector J, the discharge amount conversion coefficient Kq [mcc / Pa].
And the injection time conversion coefficient Kj [msec / mcc], and is calculated by the following equation (1).

Tjo = FQ · Kj = Pa · Kq · Kj (1)

Hereinafter, the ECU 8 sequentially corrects the basic injection time Tjo obtained by the equation (1) according to various operating states D including the atmospheric pressure Po and the like. First, the basic injection time T
jo is increased by a dead time caused by a delay in opening the injector J or the like (step S21), and subsequently, it is determined whether the engine E is in a state immediately after starting (step S21).
22).

If it is immediately after the start (ie, YES), a correction immediately after the start is added (step S23). If it is determined that it is not immediately after the start (ie, NO), the correction step S23 is not executed, and Subsequently, it is determined whether or not the intake air temperature matches the reference value (step S24).

If it is determined in step S24 that the intake air temperature does not match the reference value (that is, NO), a correction is made according to the intake air temperature (step S25), and the intake air temperature matches the reference value (that is, NO). YES),
Without executing the correction step S25, the engine E
It is determined whether or not is completely warmed up (step S26).

In step S26, if it is determined that the vehicle is not completely warmed up (ie, NO), a correction corresponding to the warmed up state is added (step S27), and if it is determined that the vehicle is warmed up (ie, YES). Then, without performing the correction step S27, the correction according to the volumetric efficiency is subsequently performed (step S28).

Further, feedback correction is performed according to the O ₂ concentration corresponding to the air-fuel ratio (step S29), and further, correction is performed according to the atmospheric pressure (step S30), and a final injection time Tj is obtained. The arithmetic processing routine of FIG. 9 ends. Hereinafter, the ECU 8 reads the injection time Tj for each ignition cycle of the engine E, and drives the injector J.

As shown in FIG. 8, since the fuel pump 3 having the pressure regulator RG is driven by a constant drive current, the engine E can make a request regardless of the amount of fuel consumed by the engine E. It is necessary to constantly pump the maximum fuel consumption.

Therefore, since the power consumption of the fuel pump 3 is always set to the maximum, the power generation amount of the alternator (not shown) increases, and the fuel efficiency of the engine E deteriorates.

The fuel pressure Pj in the delivery pipe 4
In order to keep the pressure constant, a pressure regulator RG is required as shown in the figure, which increases the cost and complicates the structure inside the fuel tank 1.

The pressure difference ΔP between the pressure Pj of the fuel supplied to the delivery pipe 4 and the intake pressure Pa of the engine E is
Is estimated and calculated by the ECU 8, there is a possibility that an error may occur between the target fuel injection amount and the actual fuel injection amount.

Incidentally, as disclosed in Japanese Patent Application Laid-Open No. 8-200124, for example, a device for detecting and feeding back the fuel pressure Pj in the delivery pipe 4 and driving the fuel pump 3 under the control of the ECU 8 has also been proposed. However, as is well known, the response of the fuel pump 3 is slow, so that the follow-up control is not sufficiently performed, which is not practical.

A device in which a plurality of pressure regulators RG having different adjustment pressures are provided so that the fuel pressure Pj can be switched in accordance with the fuel injection amount required by the engine E can be considered. The installation of a stand results in an increase in cost and is not practical.

[0024]

As described above, the conventional fuel supply system for an internal combustion engine requires a pressure regulator RG when the fuel pump 3 is driven at a constant output (see FIG. 8). The internal structure of the fuel tank 1 becomes complicated and costs increase. In addition, since the power consumption of the fuel pump 3 is always set to the maximum, the fuel efficiency of the engine E deteriorates.

If no means for detecting the fuel pressure Pj is provided as shown in FIG. 8, the ECU 8 calculates the fuel injection amount (injection time Tj). Since the pressure difference ΔP is estimated and calculated, an error occurs between the target fuel injection amount and the actual fuel injection amount.

When the fuel pump 3 is feedback-controlled based on the detected value of the fuel pressure Pj as referred to in Japanese Patent Application Laid-Open No. 8-200124, the response of the fuel pump 3 is slow. There was a problem that it was not a target. Further, when a plurality of pressure regulators RG are provided so that the fuel pressure Pj can be switched, there is a problem that the cost is increased.

The present invention has been made in order to solve the above-described problems. The present invention drives a fuel pump to a minimum necessary amount and corrects a driving amount of an injector based on a fuel pressure to reduce fuel consumption. It is an object of the present invention to obtain a fuel supply device for an internal combustion engine that has improved and reduced costs.

[0028]

According to a first aspect of the present invention, there is provided a fuel supply device for an internal combustion engine, comprising: a fuel tank filled with fuel of the internal combustion engine; and a fuel passage forming a flow path from the fuel tank to the internal combustion engine. A pipe, a fuel pump disposed in the fuel tank for delivering fuel to the fuel pipe, a delivery pipe disposed at an output end of the fuel pipe, and a fuel pipe disposed in the delivery pipe to inject fuel into the internal combustion engine For detecting the operating state of the internal combustion engine, fuel pressure detecting means for detecting the fuel pressure of at least one of the fuel pipe and the delivery pipe, and the injector and the fuel pump according to the operating state and the fuel pressure Control means for calculating a control amount of the fuel pump, wherein the control means calculates a drive current of the fuel pump in accordance with a fuel amount based on a target control amount of the injector. As well as to correct the injection time of the injector according to fuel pressure, but to inject the fuel required amount from the injector.

According to a second aspect of the present invention, there is provided a fuel supply device for an internal combustion engine according to the first aspect, wherein the fuel pressure detecting means is constituted by a pressure sensor provided on a delivery pipe.

According to a third aspect of the present invention, in the fuel supply device for an internal combustion engine according to the first aspect, the fuel pressure detecting means estimates the fuel pressure from the driving current of the fuel pump and the fuel consumption of the internal combustion engine. It is constituted by a fuel pressure calculating means for calculating.

According to a fourth aspect of the present invention, in the fuel supply device for an internal combustion engine according to any one of the first to third aspects, the control means corrects the drive current of the fuel pump in accordance with the operation state. Correction means.

According to a fifth aspect of the present invention, there is provided a fuel supply device for an internal combustion engine according to the fourth aspect, wherein the various sensors include:
A temperature sensor for detecting a temperature of the internal combustion engine; a correction means in the control means, when the internal combustion engine indicates a restart state, and when the temperature indicates a predetermined temperature or more corresponding to a warm-up state of the internal combustion engine, the fuel; This is to increase the drive current of the pump.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram schematically showing a first embodiment of the present invention. In FIG. 1, the same components as those described above (see FIG. 8) are denoted by the same reference numerals, and detailed description thereof will be omitted.

Reference numerals 3A and 8A correspond to the fuel pump 3 and the ECU 8, respectively. in this case,
Since the drive output of the fuel pump 3A is variably controlled, the pressure regulator RG (see FIG. 8) becomes unnecessary.

Reference numeral 7 denotes a pressure sensor such as a boost sensor disposed on the delivery pipe 4 and constitutes a fuel pressure detecting means for detecting a fuel pressure Pj in the delivery pipe 4. The fuel pressure Pj detected by the pressure sensor 7 is represented by EC
Input to U8A.

It is preferable that the pressure sensor 7 is disposed near the injector J in order to accurately detect the fuel pressure Pj.
May be provided in an arbitrary portion of the fuel passage, for example, in the fuel pipe 2. Also, as the intake pressure detecting means, instead of the intake pressure sensor 6, an intake amount sensor and an ECU 8A
(Operation means) may be used. In this case, the intake pressure Pa
Is estimated from the intake air amount (absolute amount) to the engine E.

The ECU 8A includes a fuel pump driving means 9 for driving and controlling the fuel pump 3A, and calculates a control amount of the injector J and the fuel pump 3A according to the operating state D, the intake pressure Pa and the fuel pressure Pj.

That is, the ECU 8A controls the injector J
The drive current Fi of the fuel pump 3A is calculated in accordance with the fuel amount based on the target control amount, and the injection time Tj of the injector J is corrected in accordance with the fuel pressure Pj, so that the required amount of fuel is injected from the injector J.

Hereinafter, the arithmetic processing operation by the ECU 8A according to the first embodiment of the present invention shown in FIG. 1 will be described with reference to the flowcharts of FIG. 2 and FIG. FIG.
Is the logic for calculating the drive current Fi of the fuel pump 3A, and FIG. 3 is the logic for correcting the injection time Tj of the injector J.

In FIG. 2, the ECU 8A first reads the rotational speed Ne of the engine E based on the crank angle signal included in the operating state D (step S1).
The injection time Tj of the injector J calculated as described above (see FIG. 9) is read (step S2).

Next, a fuel consumption amount (discharge amount of the fuel pump 3A) FQ of the engine E is calculated using a function f1 (Ne, Tj) based on the engine speed Ne and the injector injection time Tj (step S3). .

Subsequently, the intake pressure Pa detected by the intake pressure sensor 6 is read (step S4), and the fuel consumption F
The drive current Fi of the consumption pump 3A is calculated using the function f2 (FQ, Pa) based on Q and the intake pressure Pa (step S5), and the processing routine of FIG. 2 ends.

Hereinafter, the ECU 8A outputs a control command corresponding to the driving current Fi to the fuel pump driving means 9, and the fuel pump driving means 9 supplies the required driving current Fi to the fuel pump 3.
A. As a result, the fuel pump 3A is driven and controlled to deliver fuel at a required pressure.

Next, the ECU 8A calculates the injection time Tj of the injector J in accordance with the logic shown in FIG. 3, the ECU 8A first reads the fuel pressure Pj in the delivery pipe 4 detected by the pressure sensor 7 (step S6), and then reads the intake pressure Pa detected by the intake pressure sensor 6 (step S7). ).

Next, the differential pressure ΔP between the fuel pressure Pj and the intake pressure Pa is calculated by the following equation (2) (step S2).
8).

ΔP = Pj−Pa (2)

The differential pressure ΔP expressed by the equation (2) is a relative pressure when the injector J injects fuel to the intake air.

Subsequently, the injection time Tj (the value before being corrected by the fuel pressure Pj) calculated as described above (see FIG. 9).
Is read (step S9), and the corrected injection time Tj ′ is calculated by the following equation (3) using the differential pressure ΔP and the injection time Tj (step S10).

Tj ′ = Tj√ (Po / ΔP) (3)

However, in the equation (3), Po is a target value of the injection fuel pressure, and in the above-described conventional apparatus (see FIG. 8), the differential pressure between the pressure specified by the pressure regulator RG and the intake pressure Pa is obtained. Equivalent to. Also, √ (Po / Δ
P) corresponds to a correction coefficient based on the fuel pressure Pj.

Thereafter, the ECU 8A drives the injector J based on the final injection time Tj 'corrected by the fuel pressure Pj, and injects a required amount of fuel into the engine E. Thus, the processing routine of FIG. 3 ends.

In this case, the injection time Tj of the injector J
Means the actual valve opening time that does not include the dead time. Here, although the intake pressure Pa is detected to detect the intake amount of the engine E, the intake amount may be directly detected using, for example, an air flow sensor.

Thus, from the operating state of the engine E,
By calculating the fuel consumption required for the engine E and driving the fuel pump 3A so as to discharge only the required amount of fuel, the driving power of the fuel pump 3A can be reduced by about 56% compared to the conventional device. ] And reduce the fuel efficiency of the engine E by about
8% can be improved. This is the US
At the time of the FTP test, that is, the US exhaust gas test (Fed
eral Test Procedure (LA-4 test)).

The pressure sensor 7 (fuel pressure detecting means)
Is used to always detect an accurate fuel pressure Pj.
By correcting the injection time Tj according to j, the pulsation of the fuel pressure Pj generated when the injector J is driven,
The air-fuel ratio of the engine E can be accurately controlled to the target air-fuel ratio even when the pressure loss changes due to aging of the fuel filter (not shown).

Further, since the pressure regulator RG is not used, all the fuel heated in the engine room is burned by the engine E, and the high-temperature fuel does not return to the fuel tank 1. It is possible to suppress the temperature rise of the fuel and reduce the amount of the evaporated gas generated from the fuel in the fuel tank 1 by about 57%. This was confirmed by the effect of the FTP test.

Further, since the fuel pressure Pj in the delivery pipe 4 can be adjusted by controlling the driving of the fuel pump 3A, the pressure regulator RG becomes unnecessary, and the fuel supply system can be simplified and the cost can be reduced. it can. At this time, since the pressure sensor 7 is disposed on the delivery pipe 4 close to the injector J, the accurate fuel pressure Pj can be detected, and the fuel amount can be controlled with high accuracy.

Further, the difference between the actual fuel pressure and the target fuel pressure caused by the control response delay of the fuel pump can be sufficiently absorbed by correcting the injection time of the injector, so that the control of the fuel pump is controlled by open control (not using the detected fuel pressure). (No feedback) can be realized with simple control, and the system configuration can be simplified, so that cost reduction can be realized.

Embodiment 2 In the first embodiment, the pressure sensor 7 is used as the fuel pressure detecting means.
Other means may be used, for example, an arithmetic means in the ECU may be used. Hereinafter, a second embodiment of the present invention using an arithmetic means as a fuel pressure detecting means will be described with reference to the drawings.

FIG. 4 is a block diagram schematically showing a second embodiment of the present invention. In FIG. 4, the same components as those described above (see FIG. 1) are denoted by the same reference numerals, and detailed description thereof will be omitted. . 3B, 8A and 9B correspond to the fuel pump 3A, the ECU 8A and the fuel pump driving means 9, respectively.

The ECU 8B operates as a fuel pressure detecting means.
A fuel pressure calculating means for estimating and calculating the fuel pressure Pj from the driving current Fi of the fuel pump 3B and the fuel consumption (injection amount) of the engine E is included. In this case, the pressure sensor 7 described above (see FIG. 1) becomes unnecessary.

The fuel pump driving means 9B supplies the driving current Fi to the fuel pump 3B and reads the driving current Fi of the fuel pump 3B under control.

Next, the operation of the second embodiment of the present invention shown in FIG. 4 will be described with reference to FIGS. FIG. 5 is a flowchart showing the fuel pressure estimation calculation processing by the ECU 8B in FIG. 4, and S1 to S3 are the same steps as those described above (see FIG. 2).

FIG. 6 shows the discharge pressure FP of the fuel pump 3B.
FIG. 6 is a characteristic diagram showing a relationship between the fuel pump 3 and the discharge amount FQ of the injector J.
Each characteristic curve when changing in the range of [A] is shown.

Referring to FIG. 5, the ECU 8B includes an engine E
The fuel consumption FQ is calculated by a function based on the rotation speed Ne of the engine and the injection time Tj of the injector J (step S).
3) Subsequently, the driving current Fi of the fuel pump 3B under control is read via the fuel pump driving means 9B (step S11).

Next, the fuel pressure calculating means in the ECU 8B estimates and calculates the fuel pressure Pj in the delivery pipe 4 from a function based on the consumed fuel amount FQ and the driving current Fi (step S12), and the processing routine of FIG. To end.

At this time, three variables of the fuel pump 3B,
That is, the correlation between the discharge pressure FP, the discharge amount FQ (fuel injection amount), and the drive current Fi is represented as shown in FIG. 6, and when two of the three variables are determined, the remaining one variable is determined. Will be determined.

Therefore, in step S12, the fuel pressure calculating means first uses the relationship of FIG. 6 to determine the fuel consumption of the engine E (ie, the discharge of the fuel pump 3B).
The discharge pressure FP of the fuel pump 3B is obtained from the FQ and the drive current Fi of the fuel pump 3B.

Finally, the fuel pressure calculating means calculates the discharge pressure FP
The fuel pressure Pj in the delivery pipe 4 is estimated using the fact that the relationship between the fuel pressure Pj and the fuel pressure Pj becomes substantially “one to one”.

As described above, the drive current F of the fuel pump 3B is
i and the pressure estimated from the fuel consumption FQ of the engine E, the pressure sensor 7 described above (see FIG. 1) is used.
Can be replaced by an estimation operation, and the pressure sensor 7
Without the need for expensive sensor means such as the above, the same operational effects as those described above can be achieved, and further cost reduction can be realized.

Embodiment 3 In the second embodiment, the correction of the drive current Fi (corresponding to the target fuel pressure) is not particularly considered, but the drive current Fi is corrected according to the operating state D (including the intake pressure Pa). Is also good.

In general, as shown in FIG. 4, in a returnless device having a configuration in which the fuel sent from the fuel tank 1 is not recovered, the vaporization of the fuel in the delivery pipe 4 during the operation of the engine E is ignored. Can not.

For example, the engine E is warmed up (high temperature)
In the case where the fuel injection is stopped and then restarted, vaporized fuel gas is generated in the delivery pipe 4 and the actual injection amount is reduced. Therefore, the injector J is driven at the normal injection time Tj. In addition, when the fuel pump is controlled with the normal drive current Fi, the startability of the engine E is deteriorated.

When the fuel pressure FP is low, the fuel supplied to the injector J is mixed with the vaporized gas, causing a substantial shortage of fuel, which may make it impossible to control the fuel supply. Similarly, the startability of the engine E deteriorates.

Therefore, the driving current Fi according to the operating state D
By correcting (target fuel pressure), the fuel pressure Pj
It is conceivable to solve the shortage problem. Hereinafter, a third embodiment of the present invention in which the drive current Fi (target fuel pressure) is corrected according to the operating state D will be described.

FIG. 7 is a block diagram schematically showing a third embodiment of the present invention. In FIG. 7, 8C corresponds to the ECU 8B described above (see FIG. 4). The same reference numerals are given and detailed descriptions are omitted.

In this case, the various sensors 5 include a temperature sensor for detecting the temperature of the engine E (cooling water temperature or the like), and the ECU 8C includes a correction means 10 associated with the fuel pump driving means 9B.

The correction means 10 in the ECU 8C corrects the drive current Fi in accordance with the operation state D (including the temperature, the intake pressure Pa, etc.), paying attention to the fact that the target fuel pressure is related to the drive current Fi, The target fuel pressure is made variable.

For example, when the engine E is restarted when the temperature of the engine E is equal to or higher than a predetermined temperature (warm-up state), the fuel becomes insufficient at the normal driving current Fi due to the fuel vaporization phenomenon described above. Occurs, the correction means 10
Corrects the target fuel pressure by increasing the drive current Fi in the increasing direction.

Thus, the startability of the engine E can be ensured even at the time of high temperature restart. Further, since the target fuel pressure can be freely corrected and set, not only the startability of the engine E can be improved, but also the dynamic range of the injector J can be compensated, and the controllability of the engine E is further improved. Can be done.

[0080]

As described above, according to the first aspect of the present invention, the fuel tank filled with the fuel of the internal combustion engine, the fuel pipe constituting the flow path from the fuel tank to the internal combustion engine, and the fuel tank A fuel pump arranged to deliver fuel to a fuel pipe, a delivery pipe arranged at an output end of the fuel pipe, and an injector arranged in the delivery pipe to inject fuel into the internal combustion engine, Various sensors for detecting the operating state of the internal combustion engine, fuel pressure detecting means for detecting the fuel pressure of at least one of the fuel pipe and the delivery pipe, and calculating the control amounts of the injector and the fuel pump according to the operating state and the fuel pressure Control means for calculating the drive current of the fuel pump in accordance with the fuel amount based on the target control amount of the injector, Depending corrected injection time of the injector, by injecting the fuel required amount from the injector, to drive the fuel pump at the required minimum,
Since the driving amount of the injector is corrected based on the fuel pressure, there is an effect that a fuel supply device for an internal combustion engine that achieves an improvement in fuel efficiency and a reduction in cost can be obtained.

According to a second aspect of the present invention, in the first aspect, the fuel pressure detecting means is constituted by the pressure sensor disposed on the delivery pipe, so that the internal combustion engine has realized improved fuel efficiency and reduced cost. This has the effect of obtaining the fuel supply device of FIG.

According to a third aspect of the present invention, in the first aspect, the fuel pressure calculating means for estimating and calculating the fuel pressure from the driving current of the fuel pump and the fuel consumption of the internal combustion engine comprises the fuel pressure detecting means. With this configuration, an expensive pressure sensor is not required, and a fuel supply device for an internal combustion engine that achieves cost reduction is obtained.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the control means includes the correction means for correcting the drive current of the fuel pump according to the operating state. In addition, it is possible to obtain a fuel supply device for an internal combustion engine, which achieves improvement in fuel efficiency and cost reduction, and secures controllability irrespective of an operation state.

According to a fifth aspect of the present invention, in the fourth aspect, the various sensors include a temperature sensor for detecting a temperature of the internal combustion engine. And when the temperature is equal to or higher than a predetermined temperature corresponding to the warm-up state of the internal combustion engine, the drive current of the fuel pump is increased and corrected. This has the effect of obtaining the fuel supply device of FIG.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing a first embodiment of the present invention.

FIG. 2 is a flowchart showing a drive current calculation process of the fuel pump according to the first embodiment of the present invention.

FIG. 3 is a flowchart illustrating an injector injection time calculation process according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram schematically showing a second embodiment of the present invention.

FIG. 5 is a flowchart illustrating a fuel pressure estimation calculation process according to a second embodiment of the present invention.

FIG. 6 is a characteristic diagram showing a relationship between a drive current and a discharge pressure and a discharge amount of a fuel pump according to a second embodiment of the present invention.

FIG. 7 is a configuration diagram schematically showing a third embodiment of the present invention.

FIG. 8 is a configuration diagram schematically showing a conventional fuel supply device for an internal combustion engine.

FIG. 9 is a flowchart showing a process of calculating the injection time of an injector by a conventional fuel supply device for an internal combustion engine.

[Explanation of symbols]

1 fuel tank, 2 fuel pipe, 3A, 3B fuel pump, 4 delivery pipe, 5 various sensors, 6 intake pressure sensor, 7 pressure sensor, 8A, 8B, 8CECU,
9, 9B fuel pump driving means, 10 correction means, D
Operating state, E engine, Fi drive current, J injector, Pa intake pressure, Pj fuel pressure, Tj injection time.

Claims (5)

[Claims] A fuel tank filled with fuel for an internal combustion engine; a fuel pipe forming a flow path from the fuel tank to the internal combustion engine; and a fuel pipe provided in the fuel tank and provided in the fuel pipe. A delivery pump disposed at an output end of the fuel pipe; an injector disposed in the delivery pipe to inject fuel into the internal combustion engine; and an operating state of the internal combustion engine. Sensors, fuel pressure detecting means for detecting a fuel pressure of at least one of the fuel pipe and the delivery pipe, and a control amount of the injector and the fuel pump according to the operating state and the fuel pressure. Control means for controlling the fuel pump according to a fuel amount based on a target control amount of the injector. Calculates the dynamic current, the corrected injection time of the injector according to fuel pressure, the required amount of fuel of the fuel supply system for an internal combustion engine which comprises causing injected from the injector. 2. The fuel supply device for an internal combustion engine according to claim 1, wherein said fuel pressure detecting means comprises a pressure sensor disposed on said delivery pipe. 3. The fuel pressure detecting means comprises a fuel pressure calculating means for estimating and calculating the fuel pressure from a driving current of the fuel pump and a fuel consumption of the internal combustion engine. 2. The fuel supply device for an internal combustion engine according to claim 1. 4. The internal combustion engine according to claim 1, wherein the control unit includes a correction unit that corrects a drive current of the fuel pump according to the operation state. Fuel supply system. 5. The various sensors include a temperature sensor for detecting a temperature of the internal combustion engine, a correction unit in the control unit indicates that the internal combustion engine is in a restart state, and the temperature is a value of the internal combustion engine. 5. The fuel supply device for an internal combustion engine according to claim 4, wherein the drive current of the fuel pump is increased and corrected when the temperature is equal to or higher than a predetermined temperature corresponding to a warm-up state.