JPH0637859B2 - Engine throttle control device - Google Patents

Description

The present invention relates to a throttle valve control device for an engine.

[Prior art]

Recently, with respect to vehicle engines, various controls have been proposed to be electrically controlled in accordance with remarkable development of electronics, and one example thereof is conventionally disclosed in, for example, JP-A-51-138235. There is an engine throttle valve controller. That is, this is one in which the movement of the accelerator pedal is taken out as an electric signal, and the throttle valve drive motor or the like is driven by this electric signal to electrically open and close the throttle valve. In this type of throttle valve control device, the desired engine output is better than that of a normal general type in which the accelerator pedal and the throttle valve are connected by a link mechanism or a wire mechanism to mechanically open and close the throttle valve. Therefore, the throttle valve can be freely controlled so that the acceleration pedal can be obtained, and the depression force of the accelerator pedal can be reduced.

In a vehicle engine, the temperature of the engine cooling water rises to approximately 80 ° C or higher during the summer, and when the engine is stopped, the water pump also stops and cooling of the engine cooling water also stops. The temperature rises to 100 to 120 ° C due to the heat of the engine, but if you try to restart the engine in such a state, the supplied fuel will self-ignite due to the high temperature atmosphere and reverse torque will act on the starter motor. Then, there is a problem that so-called warm lock occurs and the engine cannot be started.

[Object of the Invention]

The present invention focuses on the fact that the throttle valve can be arbitrarily controlled in the above-mentioned electric control system device, and provides a throttle valve control device for an engine capable of preventing warm lock during warm start. It is a thing.

[Structure of Invention]

Therefore, the present invention is a throttle valve control device for an engine in which a throttle valve is electrically driven according to an accelerator operation amount, and when the engine is started, the throttle valve is fully closed and the fuel supply is stopped at the beginning of the engine start. However, when the engine speed exceeds a value at which the inertial force of the starter motor is sufficiently increased, the throttle valve is opened and fuel is supplied.

That is, according to the present invention, as shown in the functional block diagram of FIG. 1, the accelerator detecting means 60 detects the accelerator operation amount, and the calculating means 61 receives the output of the accelerator detecting means 60 to open the throttle valve 63. And the throttle valve drive means 62 receives the output of the calculation means 61 to drive the throttle valve 63, while the rotation speed detection means 66 detects the engine speed and the start detection means 64 starts the engine. When the engine speed is equal to or less than a value at which the inertial force of the starter motor does not sufficiently increase when the engine is started, the throttle valve 63 is fully detected. The operation means 61 outputs a signal for driving the throttle valve 63 to a predetermined opening when the engine speed becomes equal to or higher than the above value. Place of the throttle valve driving means 6
2 and the fuel supply control means 67 receives the outputs of the rotation speed detection means 66 and the start detection means 64, and when the engine rotation speed is equal to or less than the engine rotation speed at which the inertial force of the starter motor is sufficiently increased at the time of engine start, the fuel is supplied to the injector 68. The fuel supply is stopped by giving a signal, and the fuel is supplied when the inertial force of the starter motor is sufficiently higher than the engine speed.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

2 to 5 show an engine throttle valve control apparatus according to an embodiment of the present invention. In FIG. 2, reference numeral 1 denotes an engine. A throttle valve 3 is provided in the middle of an intake passage 2 of the engine 1, and a throttle actuator 4 such as a step motor or a DC motor for opening / closing the throttle valve 3 is attached. ing. A vane type air flow meter 5 is provided upstream of the throttle in the intake passage 2.
Is provided, and the upstream end of the intake passage 2 reaches the air cleaner 6.

A fuel injection valve 7 is provided on the downstream end side of the intake passage 2, the fuel injection valve 7 is connected to a fuel tank 9 through a fuel supply passage 8, and a fuel pump 10 is provided in the middle of the fuel supply passage 8. And a fuel filter 11, and a fuel return passage 12 is connected between the downstream side of the fuel filter 11 and the fuel tank 9, and a fuel pressure regulator 13 is provided in the middle of the passage 12. A constant fuel pressure is supplied to the fuel injection valve 7.

On the other hand, an exhaust gas purifying catalyst 15 is provided in the exhaust passage 14 of the engine 1, and an EGR device 16 is provided between the exhaust passage 14 and the intake passage 2. In this EGR device 16, one end of an EGR passage 17 is connected to the exhaust passage 14, the other end of the EGR passage 17 is connected to the intake passage 2, and an EGR valve 18 is provided in the middle of the EGR passage 17, The EGR valve 18 has a solenoid 19 for driving it.
Is provided.

In FIG. 2, 20 is an accelerator pedal, 21 is a battery, 22 is an igniter, 23 is a rotation speed sensor for detecting the accelerator rotation speed from the rotation angle of the distributor, and 24
Is an accelerator position sensor that detects the operation amount of the accelerator pedal 20, 25 is a water temperature sensor that detects the cooling water temperature of the engine, 26 is an intake air temperature sensor that detects the temperature of intake air, and 27 is the opening of the throttle valve 3. A throttle position sensor 28, an O ₂ sensor 28 for detecting the oxygen concentration in the exhaust gas, and a computer unit 29 for controlling the throttle opening, fuel injection amount, EGR amount and ignition timing.

Further, FIG. 3 is a diagram for explaining the arithmetic processing of the computer unit 29, and this shows the arithmetic processing of the computer unit 29 by a hardware circuit for convenience of explanation. In the figure, the same reference numerals as those in FIG. 2 indicate the same elements as in the same figure, and QaR is the output of the air flow meter 5, Ne.
Is the output of the rotation speed sensor 23, α is the output of the accelerator position sensor 24, Tw is the output of the water temperature sensor 25, and λ is O.
₂ sensor 28 output, ST is engine starter signal,
Reference numeral 53 is a starter motor of the engine.

Further, reference numerals 30 to 33 are function generating means for outputting the y value on the characteristic curve when the input is the x value, which is actually the address value input to a predetermined memory map and the stored value from the map. The y value is obtained by reading Specifically, 30 is a basic target intake air amount generation means for outputting a basic target intake air amount Qa1 according to the accelerator operation amount α, 31 is an intake air amount for guaranteeing an idle speed according to the water temperature Tw. A lower limit intake air amount generation means for outputting a lower limit value Qam of the intake air amount 32, and 32 is a maximum value of the intake air amount due to a viscous resistance or the like at the engine speed Ne, that is, an upper limit value Qa of the intake air amount.
Upper limit intake air amount generating means for outputting M, 33 is water temperature Tw
Is a water temperature correction coefficient generating means for outputting a correction coefficient CTw of the fuel injection amount in accordance with the above.

Further, 34 and 35 are function generating means for generating an output value determined by these when the input is an x value and ay value, which is actually an address input of the x value and the y value to a predetermined memory map. The output value is obtained by reading the stored value of. Specifically, 34 and 35 are EGR
This is a basic target throttle opening degree generating means for outputting a basic target throttle opening degree θ (θ1 or θ1E) determined by the target intake air amount Ac per cylinder and the engine speed Ne during non-recirculation and EGR recirculation.

Further, 36 to 41, 54 are arithmetic means for performing a predetermined arithmetic operation on various inputs, and more specifically, 36 is a target intake air amount Ac per cylinder, an output QaR of the air flow meter 5 and a rotation speed sensor 23. An intake air amount feedback correction module 37 which receives an output Ne and calculates and outputs a target throttle opening correction coefficient CaFB from the input Ne, a reference target intake air amount Qa1, a target intake air amount Ac per cylinder Ac, an engine speed Ne, and a water temperature. Output λ of Tw and O ₂ sensor 28
, A zone determination module that determines whether the engine operating region is a fuel feedback region, a fuel cut region, or an air-fuel mixture enriched region and outputs a zone determination signal Zone. Reference numeral 38 denotes a zone determination signal Zone.
And O ₂ receives the output λ of the sensor 28, the fuel feedback correction module for outputting the feedback correction coefficient CfFB of the fuel injection quantity in accordance with the output λ of the O ₂ sensor 28 in the fuel feedback control region, 39 zone determination signal Zone, feedback A fuel learning correction module that inputs the correction coefficient CfFB and learns and outputs the correction coefficient CSTD for correcting the fuel injection amount to the optimum amount in the fuel feedback region, and 40 is the zone determination signal Zon.
In response to e, the fuel cut signal SW in the fuel cut region
A fuel cut control module 41 that outputs FC, 41 receives the zone determination signal Zone, and outputs an enrichment correction coefficient CER in the air-fuel mixture enriched region, an enrichment correction module 54, a water temperature sensor output Tw, an accelerator operation amount α, a starter signal ST and This is a start-up module that receives an engine speed Ne as an input and outputs a target throttle opening θS2, a target fuel injection amount QfiS and a starter motor drive signal STA when the engine is started.

Further, 42 is a comparison / selection unit that compares the basic target intake air amount Qa1 and the lower limit intake air amount Qam and outputs the larger one as the target intake air amount Qa2, and 43 is the target intake air amount Qa2 and the upper limit intake air amount QaM. And a smaller one of them is output as the actual target intake air amount Qa3, and 44 is a correction unit for correcting the pulse width of the fuel injection pulse Tau according to the battery voltage. Also, 45,46 division means, 47 to 50 are multiplication means, 51,
52, 55 and 56 are switch means.

Further, FIG. 4 shows a more detailed structure of the start-up module 54. Reference numerals 57 and 58 are function generating means for inputting the x value and the y value, and 57 is a start-up time determined by the accelerator operation amount α and the water temperature Tw. Target throttle opening degree generating means for starting, which outputs the basic target throttle opening degree θS1, and 58, a target fuel injection amount generating means for starting, which outputs a target fuel injection quantity QfiS at starting, which is determined by the accelerator operation amount α and the water temperature Tw. 59 are input with the basic target throttle opening degree θS1 at the time of starting, the starter signal ST and the engine speed Ne, and the actual target throttle opening degree θS2 at the time of starting and the starter motor 53 are input.
Is a motor control module that outputs the drive signal STA of FIG.

Further, FIG. 5 shows a flowchart of the arithmetic processing in the motor control module 59.

In the above configuration, the starter signal ST
Is the output of the start detection means 64 shown in FIG.
Further, the computer unit 29 includes the calculating means 61, the throttle valve driving means 62 and the starting correction means 6 shown in FIG.
Each function of 5 is realized.

Next, the operation will be described with reference to FIGS.

First, the control operation of the throttle opening will be described. When the accelerator pedal 20 is depressed, the accelerator position sensor 24 detects the accelerator operation amount α, and the basic target intake air amount generation means 30 calculates the basic target intake air amount Qa1 corresponding to the accelerator operation amount α. On the other hand, the lower limit intake air amount generation means 31 calculates the lower limit value Qam of the intake air amount according to the output Tw of the water temperature sensor 25, and the comparison target selection means 42 compares the basic target intake air amount Qa1 with the intake air amount lower limit value Qam. As a result of comparison, the larger one of the two is output as the target intake air amount Qa2. Further, the upper limit intake air amount generation means 32 calculates an upper limit value QaM of the intake air amount according to the engine speed Ne.
The aM is compared with the target intake air amount Qa2 by the comparison / selection means 43, and the smaller one of them is output as the actual target intake air amount Qa3. The dividing means 45 calculates the actual target intake air Qa3 from the engine speed (Ne ×
2) Target intake air amount Ac per cylinder divided by
Is calculated, and the basic target throttle opening degree θ (θ1 or θ1E) is generated by the basic target throttle opening degree generation means 34 or 35 according to the target intake air amount Ac per cylinder, the engine speed Ne, and the presence or absence of EGR at that time. ) Is calculated.
In addition, the intake air amount feedback correction module 36 calculates a correction coefficient CaFB for feedback control of the intake air amount from the target intake air amount Ac per cylinder, the output QaR of the air flow meter 5 and the engine speed Ne to calculate the basic target throttle opening. The degree θ is calculated by the multiplier 50 by the correction coefficient Ca from the intake air amount feedback correction module 36.
Multiply correction is performed by FB, and this is output to the throttle actuator 4 as the actual target throttle opening θ2, whereby the throttle valve 3 is feedback-controlled for the opening to obtain the intake air amount according to the accelerator operation amount. . The reason why the basic target throttle opening degree θ is changed depending on the presence or absence of EGR is that the actual intake air amount differs depending on the presence or absence of EGR. Therefore, the basic target throttle opening degree is set to be larger during EGR recirculation than during non-EGR recirculation. Has been done.

Next, the control operation of the fuel injection amount will be described. When the actual target intake air amount Qa3 is calculated as described above, the dividing means 46 calculates the basic target fuel injection amount Qfi by dividing the actual target intake air amount Qa3 by the engine speed Ne, and the water temperature. The correction coefficient generation means 33 calculates a water temperature correction coefficient CTw according to the water temperature Tw, and the basic target fuel injection amount Qfi is multiplied and corrected by the multiplication means 47 by the water temperature correction coefficient CTw. Further, in the zone determination means 37, the basic target intake air amount Qa1 and the target intake air amount A per cylinder A
c, the engine speed Ne, the water temperature Tw, and the O ₂ sensor output λ, it is determined whether the current operating region of the engine is the fuel feedback region, the fuel cut region, or the air-fuel mixture enriched region. When in the enrichment region, the multiplying means 47 enriches the basic target fuel injection amount Qfi by the correction coefficient CER from the enrichment correction module 41 in addition to the water temperature correction, and the corrected target fuel injection amount is corrected. Qf
i1 (= Qfi3) is corrected by the correction means 44 in accordance with the battery voltage, and then given to the fuel injection valve 7 as a fuel injection pulse Tau. As a result, the fuel injection valve 7 is opened for a time corresponding to the pulse width of the fuel injection pulse in synchronization with the ignition timing, and the engine is injected with the actual target amount Qfi1 of the water temperature correction and the enrichment correction. Become.

On the other hand, when the engine is in the fuel feedback region, the target fuel injection amount Q after the water temperature correction by the multiplying means 48 is performed.
correction coefficient C from the fuel learning correction module 39 to fi1
The target fuel injection amount Qfi2 is multiplied by STD.
The fuel feedback correction module 3 by the multiplication means 49
The correction coefficient CfFB from 8 is multiplied to obtain the actual target fuel injection amount Qfi3, and thus the fuel injection amount is feedback-controlled. The learning correction module 39 is provided in addition to the feedback correction module 38 in order to reduce feedback control as much as possible.

Further, when the engine is in the fuel cut region, the fuel cut control module 40 outputs the fuel cut signal SWFC to open the switch means 52, whereby the fuel injection pulse is not applied to the fuel injection valve 7, and the fuel injection pulse is not applied. Will be stopped.

While the engine is in operation, the throttle opening and the fuel injection amount are controlled as described above. On the other hand, when the engine is started, a different control is performed. That is, when the engine is started,
First, the function generating means 57, 58 calculates the starting basic target throttle opening θS1 and the starting target fuel injection amount QfiS according to the accelerator operation amount α and the water temperature Tw, and the starting target fuel injection amount QfiS is the above-mentioned actual value. Instead of the target fuel injection amount Qfi3, it is input to the correction means 44, corrected there according to the battery voltage, and then given to the fuel injection valve 7 as a start-time fuel injection pulse Tau1. Will be injected and supplied.

Further, when the starter signal ST is turned on in the motor control module 59, the rotation speed sensor output Ne is read and it is determined whether the engine rotation speed Ne is 50 rpm or less (step 70). When the engine rotation speed Ne is 50 rpm or less, Is output to the throttle actuator 4 instead of the actual target throttle opening θ2 as the actual starting target throttle opening θS2, and at the same time, the start signal ST to the starter motor 53.
A is output (step 71), which causes the starter motor 53 to rotate while the throttle valve 3 is held fully closed. In this way, the starter motor 53 rotates, and the engine speed Ne becomes 50 rpm or more.
When the inertia of the engine is sufficiently increased, the basic target throttle opening degree θS1 at the time of starting is directly changed to the actual target throttle opening degree θS.
2 is given to the throttle actuator 4, whereby fuel is supplied to the engine and the engine is started (step 72).

Further, the computer unit 29 uses the igniter 22 according to the engine speed and the solenoid 1 of the EGR valve 18.
The ignition timing control and the EGR amount control are performed by adding control signals to 9 according to the operating state of the engine. Since the operations are the same as those conventionally known, detailed description will be omitted.

In the apparatus of the present embodiment as described above, when the engine is started, the inertial force of the starter motor is sufficiently increased before the fuel supply is started. This can be prevented in advance, whereby the warm startability of the engine can be guaranteed.

The present invention is not limited to the above-described embodiment, and various modifications and changes can be made. For example, if the arithmetic processing of the computer unit achieves the same function, then the processing shown in FIGS. It may be different. The control of the throttle valve may be open loop control instead of feedback control.

〔The invention's effect〕

As described above, according to the present invention, in the engine throttle valve control device in which the throttle valve is electrically driven in accordance with the accelerator operation amount, the throttle valve is fully closed at the beginning of the engine at the start of the engine. The fuel supply is stopped, and when the engine speed becomes equal to or higher than the value at which the inertial force of the starter motor increases sufficiently, the throttle valve is opened and the fuel is supplied. There is an effect that lock can be surely prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a functional block diagram showing the configuration of the present invention, FIG. 2 is a schematic configuration diagram of a throttle valve control device for an engine according to an embodiment of the present invention, and FIGS. 3 and 4 are Both are diagrams for explaining the arithmetic processing of the computer unit in the above apparatus, and FIG. 5 is a motor control module 59 in FIG.
It is a figure which shows the flowchart of the specific calculation process of. 60 ... Accelerator detection means, 61 ... Calculation means, 62 ...
... Throttle valve driving means, 63 ... Throttle valve, 64
...... Starting detection means, 65 ...... Starting correction means, 66 ...... Rotation speed detection means, 67 ...... Fuel supply control means, 3 ...... Throttle valve, ST ...... Starter signal, 23 ...... Rotation speed sensor, 24 ... … Accelerator position sensor, 29… Computer unit.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location F02N 17/08 E 8614-3G (56) References Actual development Sho 59-11164 (JP, U) Actual Kai 58-146045 (JP, U) JP 58-25853 (JP, B2)

Claims (1)

[Claims] 1. An accelerator detecting means for detecting an accelerator operation amount, a calculating means for calculating an opening of a throttle valve by receiving an output of the accelerator detecting means, and a throttle valve for driving a throttle valve by receiving an output of the calculating means. The driving means, the rotation speed detecting means for detecting the engine speed, the start detecting means for detecting the start of the engine, the output of the rotation speed detecting means and the start detecting means, and the inertial force of the starter motor at the time of engine starting are sufficient. The throttle valve is fully closed when the engine speed is less than the increasing speed, and the signal for driving the throttle valve to a predetermined opening is output to the output means when the inertial force of the cell motor is more than the sufficiently increasing engine speed. Instead, starting correction means for outputting to the throttle valve drive means,
An engine that receives the outputs of the rotation speed detection means and the start detection means and stops the fuel supply when the engine speed is equal to or lower than the engine speed at which the inertial force of the cell motor sufficiently increases at engine startup, and sufficiently increases the inertial force of the cell motor. A throttle valve control device for an engine, comprising: a fuel supply control means for supplying fuel when the rotational speed is equal to or higher than the rotational speed.