JPS6189944A - Controller for throttle valve of engine - Google Patents

Abstract

PURPOSE:To design improvement of deceleration performance by stopping fuel supply and correcting a throttle valve to fuel opening or high opening close to the fuel opening when an engine is decelerated. CONSTITUTION:State of decelerating operation of an engine is detected by a detecting means 52 for state of decelerating operation. Fuel supply is stopped by a fuel stopping means 53 in the state of decelerating operation of an engine. A high speed signal of an engine speed detecting means 27 and the signal of the above fuel stopping means 53 are input to a correcting means 55, and a throttle valve opening is corrected to high opening close to full opening when fuel supply is stopped and the engine speed is high. Deceleration performance is improved by this mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an engine throttle valve control device, and more particularly, to an engine throttle valve control device that electrically controls the throttle valve opening in order to obtain a predetermined intake air amount with respect to an accelerator operation amount that indicates a required engine output. This paper relates to the improvement of the control system.

(Prior Art) Conventionally, as a technique for controlling the amount of intake air supplied to the engine to a predetermined intake amount in response to the amount of accelerator operation indicating the required engine output, as shown in Japanese Patent Laid-Open No. 51-138235, The throttle valve opening control means includes an accelerator detection means for detecting an operation amount, and a throttle valve opening degree control means for receiving the output of the accelerator operation amount and controlling the opening degree of the throttle valve according to the accelerator operation amount. It is known that the J, Unishashino, uses feedback control to control the opening according to the amount of accelerator operation. Then, by supplying the amount of fuel to the engine so that the air-fuel ratio is set in advance according to the amount of intake air based on the throttle valve opening, the air-fuel ratio of the engine is set to the target level. be.

(Problem to be Solved by the Invention) By the way, since r: generally does not require engine output during deceleration operation of the engine, it is possible to improve fuel efficiency by stopping the fuel supply to each cylinder. , engine braking performance is improved by increasing the engine's pumping loss.

In the above-mentioned conventional throttle valve control device, it is conceivable to fully open the throttle valve as is normally done in order to improve the engine braking performance during deceleration operation when fuel supply is stopped. It turns out that is not always effective. That is, the present inventors measured the engine braking effect when the throttle valve is fully closed and when the throttle valve is fully open against engine rotation failure during deceleration operation during fuel stop, and found that the fourth
As shown in the figure, when the throttle valve is fully closed, the pumping loss of the engine is mainly caused by the intake resistance, so as the engine speed increases, as shown by the solid line in the figure, the engine pumping loss increases almost directly to P81 (- When the throttle valve is fully open, the pumping loss of the engine is mainly caused by the push-out resistance of the intake air. Accordingly, C has a characteristic that increases almost quadratically, and both characteristics intersect at a predetermined rotation speed (for example, 4000 rl) m>. For this reason,
In the high engine speed range above the above-mentioned specified speed, where a true engine braking effect is desired, the pumping loss (that is, the engine braking effect) when the throttle valve is fully open is lower than when the throttle valve is fully open, and the engine braking effect is not so high. Become something.

The present invention has been made in view of the above, and its purpose is to stop the fuel supply during deceleration operation of the engine as described above, and to stop the fuel supply during deceleration operation of the engine. By correcting the opening of the throttle valve to a high degree in the entire range, engine braking performance can be further improved in the high engine speed range where a true engine braking effect is desired, and deceleration performance can be improved. be.

(Means for Solving the Problems) In order to achieve the above object;
As shown in the figure, an accelerator detecting means 19 for detecting the amount of accelerator operation, receiving the output of the accelerator detecting means 19,
An engine throttle valve control 21 comprising a throttle valve opening degree control means 37 for controlling the opening degree of the throttle valve according to an accelerator operation amount, and a deceleration operation state detection means 52 for detecting a deceleration operation state of the engine. , a fuel stop means 53 that receives the output of the deceleration operation state detection means 52 and stops fuel supply to the cylinder during engine deceleration operation, and an engine rotation speed detection means 27 that detects the engine rotation speed.
The fuel stop means 53 and the engine speed detection means 2
7, when the fuel is stopped and the engine speed is above a predetermined speed where the pumping loss of the engine when the thrower valve is fully open is greater than that when the throttle valve is fully open, the throttle valve is turned on. The configuration includes a correction means 55 that performs correction control on high pitch marks in the vicinity of full opening.

(Function) With the above configuration, in the present invention, during deceleration operation of the engine,
Fuel supply to the cylinders is stopped to improve fuel efficiency, and when the engine speed is higher than a predetermined speed, the throttle valve is corrected to close to full power (power is high). This increases the pumping loss, increases the engine braking effect, and improves deceleration performance.

(Example) Hereinafter, an example of the present invention will be described based on the drawings from FIG. 2 onwards.

Figure 2 shows the overall configuration of an engine control device according to an embodiment of the IJ* invention, where 1 is, for example, a 4-cylinder engine, 2 has one end connected to the engine via an air cleaner 3, and the other end connected to the engine 1. An intake passage 4 supplies intake air (air) to the engine 1, and an exhaust passage 4 has one end opening into the engine 1 and the other end opening into the atmosphere to discharge exhaust gas from the engine 1. Reference numeral 5 denotes an accelerator pedal that is depressed in response to the engine output request; 6 a throttle valve that is disposed in the intake passage 2 and increases the amount of intake air by +1+'J1)II; There is no mechanical linkage, and as will be described later, it is electrically controlled by the amount of depression of the accelerator pedal 5, that is, the amount of accelerator operation.

Reference numeral 7 denotes a throttle actuator 1 consisting of a step motor or the like that opens and closes the throttle valve 6.

Reference numeral 8 denotes a catalyst device which is interposed in the exhaust passage 4 and purifies exhaust gas.

Further, 9 has one end opening upstream of the catalyst device 8 of the exhaust passage 4 and the other end opening downstream of the throttle valve 6 of the intake passage 2.
An exhaust gas recirculation passage 10, which recirculates part of the exhaust gas from the exhaust passage 4 to the intake passage 2, is interposed in the middle of the exhaust gas recirculation passage 9, and circulates the exhaust velocity flow m in one direction. Create negative intake pressure! III
A reflux control valve 11 is a solenoid valve that controls opening and closing of the reflux control valve 10.

On the other hand, reference numeral 12 denotes a fuel injection valve disposed downstream of the throttle valve 6 in the intake passage 2 to inject and supply fuel;
Port fl +3-1 valve 12 is fuel pump 13.115
J: Supply port 31 with fuel filter 14 interposed
B 15 is fP connected to fuel tank 1G and d'3
First, when the fuel from the fuel tank 16 is fed, the excess fuel is flowed into the fuel tank 16 via the fuel pressure regulator 17 or the turn passage 18,
Therefore, fuel at a predetermined pressure is supplied to the fuel injection valve 12.

In addition, 19 is an accelerator pedal position sensor as an accelerator detection means for detecting the accelerator operation amount α based on the amount of depression of the accelerator pedal 5, and 20 is arranged upstream of the throttle valve 6 in the intake passage 2 to detect the intake air ff1Q.
1 is an aflow meter that detects aR; 21 is an intake air temperature sensor that is also arranged upstream of the throttle valve 6 in the intake passage 2 and detects the intake air temperature; 22 is a throttle position sensor that detects whether the throttle valve 6 is open; Water temperature sensor that detects engine cooling water shortage 4ITW, 24
02 sensor is disposed upstream of the catalytic device 8 in the exhaust passage 4 and detects the air-fuel ratio λ of the engine 1 based on the 4-degree oxygen iI component in the exhaust gas; 25 is attached to the recirculation control valve 10 during exhaust flow A reflux sensor that detects these 19 to 2
The detection signal 5 is input to a control unit 26 consisting of an analog computer, etc., and the control unit 26 controls the throttle actuator 1 7,
Solenoid valve 11 and fuel injection valve 12 are controlled.

Further, an igniter 27 is connected as an input to the control unit 26, and inputs a signal indicating the number of ignitions, that is, the engine rotation speed Ne, and constitutes engine rotation speed detection means. In addition, the control unit 2
A dust distributor 28 and a battery 29 are input-connected to 6, and receive signals of ignition timing J5 and battery voltage Ve, respectively.

Next, the operation of the control unit 26 will be explained in detail with reference to FIG. Note that FIG. 3 shows the case of a four-cylinder engine.

In FIG. 3, first, the throttle valve distance control system will be described.MAI is a system in which the target 1tflQal of the air supplied to the engine 1 is set so that the air-fuel ratio is set in advance for the accelerator operation amount α. The set first map receives the output from the accelerator position sensor 19 and supplies it to the engine 1 according to the accelerator operation amount α.
I am trying to set the target air ff1Q11 to
M A 2 is the minimum air Fl to achieve the air-fuel ratio required for idle up with respect to the engine cooling water temperature a T w.
This is a second map in which iQam is set, which receives the output from the water temperature sensor 23 and sets the minimum air IQam for water temperature correction according to the engine coolant temperature Tw.

31 is the first map MAL and the second map M^2.
The target air 1? obtained from the first map MAI after receiving each output of The maximum value Qa of IQa+ and the minimum air for water temperature correction fi Q am obtained from the second map MAx
2, and the target air mQ
When a+ is lower than the minimum air for water temperature correction f7'tQam, the minimum air for water temperature correction Ffi is increased to increase the idle.
Q am is selected to ensure good engine operability. Further, MA3 is a third map in which the maximum air fflQaM determined by the engine speed tt NC is set with respect to the engine speed Ne, and receives the output from the igniter 27 and is set according to the engine speed Ne. The maximum air ffiQaM is set. , 32 receive the outputs of the maximum value selection circuit 31 and the third map MA3, are determined by the maximum value selection circuit 31, and are calculated as 1. : The minimum value Q of the maximum air m Q a 2 and lζ maximum air ffiQaM obtained from the third map MA3
The minimum value selection circuit selects a3, and when the target air flQa1 exceeds the maximum air ffiQaM determined by the engine speed NO, the minimum value selection circuit selects the amount of air that can be taken in when the throttle valve 6 is fully open as the target value. Since this is also meaningless, by selecting the maximum air fflQaM and limiting the maximum value, a full open signal corresponding to the fully open throttle valve 6 is output to the subsequent stage. As described above, the target air moa 3 is determined for the accelerator operation amount α, taking into account the correction for the engine coolant temperature Tw and the correction for the maximum air amount when the throttle valve 6 is fully open, which is determined by the engine rotation @Ne.

Furthermore, 33 receives the output from the minimum value selection circuit 32, and selects the target air fAQa3 from the engine speed VINe.
The intake air ff1Ac+ per cylinder in a 4-cylinder engine is calculated using a zero remover that removes the air by a value twice (NeX2). M to J and MA5 are the 4th J and 5th maps in which the throttle valve opening θ1 or θIE to be set as the target intake air ff1Ac+ for the engine rotational speed NO when exhaust gas recirculation is stopped and when exhaust gas is flowing, respectively. , both maps MAa and MAs are selected by a recirculation switch 34 which switches between when exhaust recirculation is stopped and when exhaust recirculation is performed according to a signal from the recirculation sensor 25, and receive the output from the divider 33, and should be set as the target intake mAc+. The throttle valve opening degree θ1 or θ1ε is set. Further, 35 is an intake air amount feedback correction module which receives a signal of the target intake air ff1Ac+ from the divider 33, and also receives a signal of the actual air ff1Q a r< actually measured by the air 70-meter 20 and the engine rotation speed NO. Then, the actual intake air per cylinder ff1Ac R calculated by the actual air amount QaR and the engine rotation speed Ne is compared with the target intake m8C1, and according to the deviation [To feedback correct the throttle valve opening] The feedback correction coefficient CaFB is calculated. Furthermore, 36
is the fourth or fifth map MA4. Receives each output from MA5d3 and intake air amount feedback correction module 35, and outputs the map MA4. The multiplier 36 is a multiplier that corrects the target throttle valve opening θ1 or θ1ε obtained by MA s using a feedback correction coefficient CaF[] obtained by an intake m feedback correction module 35. The signal of the target throttle valve opening θ2 corrected by
The opening degree of the throttle valve is controlled to the target throttle valve opening degree 02. As described above, 17 of the C throttle valve 6 receives the output of the accelerator pedal position sensor 19 and responds to the accelerator operation amount α.
It constitutes a throttle valve opening control means 37 that controls the ailJ from 0 degrees to the target opening θ2.

Next, to describe the fuel supply m control system in FIG. The sixth map is the target fuel f to be supplied to the engine 1 according to the accelerator operation amount α in response to the output from the accelerator pedal position sensor →
f1Qf+ is set. MB7 has a minimum fuel consumption of 62 liters Qfm with respect to the engine cooling water temperature Tw so that the air-fuel ratio necessary for the idle I knob is obtained with respect to the air f2kQam set in the second map MA2.
This is the seventh map that has been determined, and receives the output of the water temperature sensor 23, and sets the minimum fuel consumption Fl height Qfm for water temperature correction according to the engine cooling water temperature Tw. 39 is the above sixth map M
B6 and the seventh map MB7, the target fuel 11ffiQf+ determined by the sixth map Me6 and the seventh
Minimum fuel FjJQ for water temperature correction determined by MAP MB7
This is a maximum value selection circuit that selects the maximum value Qf2 behind fm, and when the target fuel 1 maximum Qft is lower than the minimum fuel temperature l fA Q fm for water temperature correction, it selects the water temperature correction coefficient I1 (fuel The highest Qfm in gear A is selected to ensure good engine drivability.Also,
Msa is the maximum air f set in the third map MAs above.
An eighth map in which the maximum fuel mQfM with respect to the engine rotation speed Ne is set so that the target air-fuel ratio is set in advance with respect to flQaM, and the maximum fuel mQfM is set with respect to the engine rotation speed Ne
(The maximum fuel ffiQfM is set according to 3. 4o is the maximum fuel mQf2 obtained by the three maximum flfI'r'iU selection circuits after receiving each output of the three maximum value selection circuits and the eighth map Mss. This is a minimum+a selection circuit that selects the minimum value Qf3 from the maximum fuel (4)QfM found in the eighth map MeB, and the above target fuel ff1Q.
The maximum fuel can where f1 is determined by the engine speed Ne,
When the air ff1Qa+ exceeds the maximum air ffiQaM determined by the engine speed Ne, the throttle valve 6
When the target value is 117), which is more than the amount of air that can be inhaled when fully opened, the maximum air ffiQaM is selected (
ζ By selecting the maximum fuel amount QfM, the target value Qf+ of the sixth map Ms6 is corrected so that the intake air m supplied to the engine 1 becomes a preset target air-fuel ratio. As described above, in the same way as in the case of early air, the accelerator operation ■ α is used to make a correction for the engine cold 13 water lag Tw and a correction for the maximum fuel can with the throttle valve 6 fully open determined by the engine speed Ne. The considered target fuel characteristic Qf3 is determined.

Then, the target fuel r1 suspension Q from the maximum value selection circuit 40 is
The f3 signal is transmitted through a divider 41 and first to third multipliers 42 to 44.
, is output to the fuel injection valve 12 via the fuel cut switch 45 and the fuel injection valve correction circuit 46. The bullet remover 41 receives the output from the minimum tlti selection circuit 40, and eliminates the target fuel amount Qf3 by using the upper engine rotation error Ne, assuming that fuel is injected into two cylinders at the same time. 1 supply ff1Qfi is calculated. Further, the first power σ generator 42 calculates the target fuel supply 1Qfi obtained by the remover 41 using the water temperature correction coefficient CTw and the enrich correction module 47 for the engine cooling water temperature Tw obtained by the ninth map Mes. The target fuel supply mQ is multiplied by the enrichment correction coefficient CER.
This is to calculate f i +. This enrichment correction module 47 is a zone determination module 51 which will be described later.
When the intake air ff1Ac+ relative to the engine speed Ne is in the 1 enrichment line region based on the zone signal from .

Further, the second multiplier 43 converts the target fuel supply rl Q f i 1 obtained by the first multiplier g1 42 into the learning correction coefficient C3T obtained by the fuel learning correction module 48.
The target fuel supply amount Qfi2 is calculated by multiplying D by i and correcting it. This fuel learning correction module 48 adjusts the fuel feedback correction conditions in the fuel feedback correction module 49 based on the zone signal from the zone determination module 51 and the fuel feedback correction coefficient CfFB signal from the four fuel feedback correction modules described below. For example, when 2 seconds or more have passed after the establishment of the condition, the fuel learning correction coefficient C5TD is set to its initial value - 1.0, and then
The following formula % formula % Cfpo peak value + bottom value of the past 8 Cfp days)/16-1. O) is used to sequentially update and output the data.

Further, the third multiplier 44 multiplies the target fuel F3+supply ff1Qriz obtained by the second multiplier 43 by the fuel feedback correction coefficient CrF3 obtained by the fuel feedback correction module 49! 7? +i is corrected and the target fuel supply (4) Qfi3 is calculated by Cne. This fuel feedback correction module 49 (Y), zone 1 correction from the zone determination module 51 and 02 sensor 24
Based on the air-fuel ratio λ signal from
The intake air ΦAC+ with respect to the engine rotation speed Ne is outside the enrich line and fuel cut zone ■ The 02 sensor 24 is active: When cleaning, the fuel feedback correction coefficient Cfpo (e.g. 0.8
≦C (F13≦1.25, proportional constant P=0.06, integral constant 1=0.05/sec).

Furthermore, the opening and closing of the twin cut switch 45 is controlled by an output signal from the twin cut control module 50. Based on the zone signal from the zone determination module 5 lb+ + and the signal of the target intake air amount Act, the twin air cut control module 5o operates under, for example, the following condition (i) Engine cooling water temperature Tw>60'
C■ Intake ff1Ac+<10% of cylinder stroke volume■
It controls so that the fuel cut switch 45 that cuts fuel injection is activated during the engine deceleration operation state where the engine rotational speed Ne>1100 Orp is satisfied.
As described above, the deceleration operation state detection means 52 and the fuel stop means 53 which receive the output of the deceleration operation state detection means 52 and stop the fuel supply to the cylinders during engine deceleration operation are configured. The control module 1 to control module 50 controls the engine rotation speed Ne of the Eve knife 27 during the fuel stop while controlling the control switch 45.
Based on the signal, for example, the following condition engine rotation speed Ne>40
When 0Qrpm is satisfied, a full-open signal θ3 corresponding to the full opening of the throttle valve 6 is output. Therefore, it receives the respective outputs of the fuel stop means 53 and the evening knife 27, and controls the entire throttle valve 6 when the fuel is stopped and the engine speed Nc is at that time. When the pumping loss of the engine 1 is equal to or higher than a predetermined rotational speed (4,000rpm) higher than that when the throttle valve 6 is fully closed, that is, when the engine is in a high rotational speed range, a correction means that silently corrects and controls the throttle valve 6; 55 have been established. Here, the zone determination module 51 determines the engine rotation speed Ne, the target intake air ff1
A condition determination signal (zone signal) for each of the control modules 47 to 50 is created based on the signals Ac+, engine coolant temperature Tw, and air-fuel ratio λ.

Furthermore, the fuel injection valve correction circuit 46 includes the third fuel injection valve correction circuit 46.
Receives the target fuel supply amount Q fi3 signal from the multiplier 44 and the battery voltage Ve signal from the battery 29, and corrects the pulse signal as the target fuel supply m signal to the fuel injection valve 12 according to the fluctuation voltage v8. fuel injection valve 12
This is what is output to. As described above, the fuel injection valve 12
is driven for a predetermined period of time in synchronization with ignition, and the fuel supply area is controlled to a target value txt+-.

Therefore, in the above embodiment, the Akvil operation 6)
A target air (5) Qa+ is determined according to α, a target throttle valve opening distance θ2 is determined based on the determined target air ff1Qa+, and the target throttle valve opening distance IIθ
The throttle valve opening control means 37 controls the throttle valve opening control means 37 to control the throttle valve opening control means 37 so that the throttle valve 6 reaches the target air ffFQ.
Air of a is supplied to the engine '1.

In this case, when the accelerator pedal 5 is released and the engine is decelerated, the fuel stop means 53 stops the fuel supply from the fuel injection valve 12, improving fuel efficiency, and the engine output becomes low. At the same time, the engine speed N
In the engine high speed range where o > 400 Or 11 m, where a true engine braking effect is desired, the throttle valve 6 is forcibly corrected to be fully open based on the throttle valve fully open signal θ3 by the correcting means 55, so that the engine 1 as shown in FIG. The pumping loss increases by l< compared to when the throttle valve 6 is fully opened in response to the accelerator operation early α, thereby improving the engine braking effect and improving the deceleration performance. On the other hand, even if there is C during deceleration operation, the engine speed N
In the low rotation range of o≦400 Orpm, the correction means 55 does not operate, and the opening of the throttle valve 6 is fully opened according to the throttle valve opening control means 37 according to the accelerator operation 1' [skewer α]. When the throttle valve 6 is controlled to be fully open as shown in FIG. 4, the relative engine braking effect increases and the deceleration performance improves.

In addition, the target air amount and fuel supply amount are respectively determined for the accelerator operating device α, and based on the determined target values, the intake air amount and fuel supply amount are simultaneously adjusted to the target values. By being controlled so that the intake air amount and fuel supply m change simultaneously to the target 11fI with no time lag between them in response to a change in the accelerator operating device α, transient operation of the engine is prevented. The air-fuel ratio of the engine can be accurately controlled 20 to the target air-fuel ratio without causing any deviation in fuel response even when the engine is in use, thereby improving the acceleration performance and driving performance of the engine.Moreover, Since the intake air amount and fuel supply amount are simultaneously controlled in response to the accelerator operating finger α so that the air-fuel ratio is set in advance, it is possible to accurately control the air-fuel ratio to the target air-fuel ratio without requiring feedback control. Therefore, control can be simplified.

In the above embodiment, during engine deceleration operation, the engine rotation speed Ne is a predetermined rotation speed (4000 rpm).
), the throttle valve is corrected to fully open in the high rotation range exceeding
In the low rotation range below the predetermined rotation speed, the throttle valve is controlled to be fully open according to the accelerator operating device α, but the present invention is not limited to this, and in the high rotation range below the predetermined rotation speed, the throttle valve is controlled to close to full throttle (with high force). Even if the opening degree is corrected, the same effect as in the above embodiment can be obtained11.In addition, the setting of the predetermined rotation speed is also selected appropriately according to each engine, and the point is that the engine rotation speed at that time is selected as appropriate. Pumping loss when the throttle valve is fully open is greater than that when the throttle valve is fully open J: If the throttle valve opening is corrected to fully open when the rotation speed is below the specified number, the engine high speed range where you truly want the engine braking effect. This can improve engine braking performance.

(Effects of the Invention) As explained above, according to the present invention, during engine deceleration operation in which fuel supply to the cylinders is stopped, the pumping loss of the engine with the throttle valve fully open exceeds that with the throttle valve fully open. The C throttle valve in the high speed range is corrected to a high opening of fully open or close to full, increasing engine braking performance in the high engine speed range where true engine braking effect is desired, and improving deceleration performance. It is possible to achieve this goal.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the configuration of the present invention. Figs. 2 to 4 show embodiments of the invention, Fig. 2 is an overall schematic block diagram, and Fig. 3 is an operational flow of the control unit. Figure 4 shows the engine braking effect characteristics when the throttle valve is fully closed and fully opened due to engine rotation failure. 1...Engine, 5...Accelerator pedal, 6...
Throttle valve, 7... Throttle actuator, 1
1...Accelerator pedal position sensor, 26...
Control Nishi Knit, 27...Igniter, 37
. . . Throttle opening 1111 river means, 52 . . . Deceleration operation state detection means, 53 . . . Fuel stop means, 55.
...Correction means.

Claims (1)

[Claims] (1) Accelerator detection means for detecting the amount of accelerator operation;
A throttle valve control device for an engine, comprising a throttle valve opening control means for receiving an output of the accelerator detecting means and controlling an opening of the throttle valve according to an accelerator operation amount, the device detecting a deceleration operating state of the engine. a deceleration operation state detection means for detecting the deceleration operation state; a fuel stop means for receiving the output of the deceleration operation state detection means and stopping fuel supply to the cylinder during engine deceleration operation; and an engine rotation speed detection means for detecting the engine rotation speed; A predetermined rotational speed that receives the outputs of the fuel stop means and the engine rotational speed detection means, and the pumping loss of the engine when the engine is stopped and the engine rotational speed is at that time is higher than that when the throttle valve is fully closed. A throttle valve control device for an engine, comprising a correction means for correcting and controlling the throttle valve to a high opening degree close to fully open in the above case.