JPS60247018A - Fuel control device in combined intake-air type engine - Google Patents

Abstract

PURPOSE:To prevent the output of an engine from varying upon change-over from the condition in which a secondary intake-air valve rests to the condition in which first and second intake-air valves operate, by temporarily increasing the amount of fuel fed to an intake-air passage before the change-over. CONSTITUTION:In the main control section of a controller 29, required basic data are multiplied by compensating coefficients in accordance with data from sensors 17-28 to obtain a fuel injection pulse width, and the amount of fuel fed to a combustion chamber in an engine E by means of a fuel supply amount setting means M4. If the high load condition of the engine E is detected during a period exceeding a set time and a high temperature of supplied air is detected, a fuel increase amount control means M5 controls fuel injection valves 9, 10 such that fuel in an amount which is larger than a supply amount set beforehand by the means M4, is fed a combustion chamber to enrich the air-fuel ratio, in preference to the fuel supply amount setting means M4. Thus, the air-fuel ratio of mixture in an intake air passage 1 becomes suitable, thereby it is possible to prevent the output of the engine from varying and so forth upon change-over of intake valves.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for controlling the fuel quantity of a compound intake ennon.

[Conventional technology]

Conventionally, some engine idle control devices detect engine speed, throttle valve opening, vehicle speed, etc., and supply control signals based on these detection signals to the motor to move the engine forward or backward. By moving the stop position of the throttle valve, feedback control of the engine speed (rotation speed feedback control) is performed under certain conditions during idling operation. A system has been proposed in which position feedback control can be performed.

[Problem that the invention seeks to solve]

However, if a conventional engine fuel control device is simply applied to a compound intake type engine, in an engine that supplies fuel to the intake passage, when the primary intake valve is activated (hereinafter, this state is expressed by the symbol rPJ). ) to the operation of the primary intake valve and the secondary intake valve (hereinafter, this state will be referred to as "P1S").
There is a problem that the image becomes thinner temporarily, and this causes
There is a problem in that the engine output changes and shock occurs.

In other words, when the secondary intake valve is stopped, the secondary intake passage has a
Since the extremely lean air-fuel mixture remains, the air-fuel mixture supplied to the combustion chamber becomes lean.

The present invention aims to solve such problems, and even when switching from operating only the primary intake valve to operating both the primary intake valve and the secondary intake valve, there is no flow into the combustion chamber. An object of the present invention is to provide a fuel control device for a compound intake type engine that can prevent the occurrence of switching shock by keeping the air-fuel ratio of a supplied air-fuel mixture almost constant.

[Means for solving problems]

For this reason, the fuel control device for a compound intake type engine of the present invention has a primary intake system with a primary intake valve that operates over the entire operating range, and a valve operation stop mechanism that operates in a part of the operating range. In a composite intake type engine having a secondary intake system having a secondary intake valve, a fuel supply means for supplying fuel to the intake passage of the engine is provided, and the engine starts from the time when the secondary intake valve stops. The present invention is characterized in that a fuel increase control means is provided for temporarily increasing the amount of fuel supplied to the intake passage before switching to the operation state of the secondary intake valve and the secondary intake valve.

[For production]

With the above configuration, when the secondary intake valve is stopped (i.e., 1
Before switching from (when only the secondary intake valve is activated) to when the primary and secondary intake valves are activated, the amount of fuel supplied to the intake passage is temporarily increased, and a constant air-fuel ratio is supplied to the combustion chamber. Air-fuel mixture is supplied.

〔Example〕

Hereinafter, embodiments of the present invention will be explained with reference to the drawings.
The figures show a fuel control system for a compound intake type engine as an embodiment of the present invention. Figure 1 is an overall configuration diagram thereof, and Figure 2 is a configuration diagram showing a valve operation stop device of the engine valve system. , Fig. 3 is a partial plan view of the lock plate, Fig. 4 is a configuration diagram of its main parts, Fig. 5 is a vertical sectional view of the main parts of the engine, and Fig. 6 schematically shows the main parts of the engine. The plan view, FIGS. 7 to 11, and FIGS. 12 (, ) to (11) are all graphs for explaining the operation, and FIGS. 13 to 17 are flow charts for explaining the operation.

As shown in Figure 1 and Figure 6, the in-line four-cylinder gasoline engine for automobiles and the internal combustion engine E (hereinafter simply referred to as "Engine EJ") according to this embodiment are equipped with a turbocharger 3. The turbocharger 3 includes a turbine 4 installed in the exhaust passage 2 of the engine E, and a compressor 5 installed in the intake passage 1 of the engine E and rotationally driven by the turbine 4.

It should be noted that a bypass passage that bypasses a portion of the exhaust passage 2 where the turbine is disposed is connected to the exhaust passage 2, and a waste gate valve 6 is provided to open and close this bypass passage.

This wastegate valve 6 is configured to be opened and closed by a two-diaphragm pressure-responsive device 7, or is pressure-responsive by an electromagnetic switching valve 34 (this valve 34 has a return spring (not shown) for the valve body). By selectively supplying atmospheric pressure and supercharging pressure to one pressure chamber of the device 7, the opening timing of the waste gate valve 6, etc. is adjusted, and at least two
It is now possible to realize the supercharging pressure characteristics of the species.

Further, in the intake passage 1 of the engine E, from the upstream side (air cleaner side), air 70 - sensor 16 . Compressor of turbocharger 3 5. Intercooler 8. Electromagnetic fuel injection valves 9 and 10 (these valves 9 and 10 have different injection capacities) and a throttle valve 11 are provided in the exhaust passage 2 of the engine E, and in order from the upstream side (engine combustion chamber side), A turbine 4° catalytic converter 31 of the turbocharger 3 and a 77 roller (not shown) are provided.

As shown in FIG. 4, a shaft 1.1a of a throttle valve 11 disposed in the intake passage 1 of the Ennon E is connected to a throttle lever 11c outside the intake passage 1.

Finally, the end lid of the throttle lever 11c is such that when the accelerator pedal (not shown) is depressed, the throttle valve 11 is rotated in the clockwise direction (opening direction) in FIG. 4 via the throttle lever 11c. wire (not shown)
is connected to the throttle valve 11, and a return spring (not shown) is attached to the throttle valve 11 to bias it in the closing direction, so that when the tensile force of the wire is weakened, the throttle valve 11 closes. It's starting to get better.

By the way, when the engine is idling, the throttle valve 1
An actuator 12 is provided to control the opening degree of 1, and this actuator 12 has a worm 14 on its rotating shaft.
A DC motor (hereinafter simply referred to as "motor") having a
13, and this motor 13 has a ohm 1
4a meshes with an annular worm wheel 14b.

A pipe shaft 14c having a female screw portion 14d is integrally provided on the ohm wheel 14b, and a rod (stopper member) 15 has a male screw portion 15a that engages with the female screw portion 14d of the pipe shaft 14c. ohm wheel 141) and the pipe shaft J4c.

The tip of the rod 15 is connected to the throttle lever 1 via an idle switch 25 as an idle sensor.
When the throttle valve 11 is in a fully open state, it comes into contact with the end lid of the throttle valve 1c. That is, the rod 15 restricts the fully open stop position of the throttle valve 11.

Here, the idle switch 25 is a switch that is turned on (closed) when the throttle valve 11 is at the fully closed stop position (during engine idling operation) and turned off (open) otherwise.

Note that a long hole 151) is formed in the rod 15, and a pin (151) on the actuator body side is inserted into this long hole 151).
(not shown), and the 50 rod 15 is prevented from rotating.

In this way, the tip of the rod 15 is in contact with the engine E when it is in idle operation, so the motor
3 in a certain direction, the pipe shaft 14c is rotated via the ohm gear, and the rod 15 is protruded (advanced) from the actuator 12, which opens the throttle valve 11 and rotates the motor 13 in the opposite direction. When the rod 15 is retracted (retracted) into the actuator 12, the throttle valve IJ can be controlled to close by the action of the return spring.

That is, by driving the rod 1'15, the full-open stop position of the throttle valve 11 is changed, and the idle opening degree of the throttle valve 11 is controlled.

In this embodiment, the engine E is configured as a CIS engine equipped with a primary intake system and a secondary intake system that communicate with each cylinder S1 to S4. The secondary intake system IS includes a primary intake valve 40 that operates throughout the engine, and a secondary intake system IS that stops operating in a low engine speed range and starts operating in a high engine speed range.
A secondary intake valve 41 is provided.

In the engine valve train system of this embodiment, the primary intake valve 4
The 0 and secondary intake valves 41 and the exhaust valves 42 are each driven to open and close by a cam via a rocker arm.As shown in FIG. 102 is provided with a valve operation stop mechanism M'.

That is, a cylinder 112 is attached to the rocker arm 102, and a bottomed cylindrical plunger 113 is slidably fitted into the cylinder 112.

The planner 113 is pressed downward in FIG. 2 by a spring 114 installed inside it, and
The bottom surface portion of the lower end is in contact with the valve shaft end of the secondary intake valve 119 .

Furthermore, two elongated holes 112a are formed in the cylindrical wall of the cylinder 112 at positions directly above the upper end of the plunger 113 when the plunger 113 is at the lowest position relative to the cylinder 112 (the position shown in the figure). A lock plate 106 constituting the locking mechanism EN is inserted into these long holes 112a.

And, the tip of this lock plate 10G has two forks 7
As shown in FIG. 3, this bifurcated 7-orc portion is formed as a narrow gap portion 106a that is approximately equal to the inner diameter of the plunger 113 at its tip end portion, and as shown in FIG. A portion near the end is formed as a wide gap portion 106b that is slightly wider than the outer diameter of the plunger 113.

Further, the rocker arm 102 includes a cylinder 104, a piston 105 that slides within the cylinder 104, and is interposed between the piston 105 and a spring receiver 108 to press the piston 105 to the right in FIG. A hydraulic actuator 103 consisting of a return spring 107 is provided.

The piston 105 and the lock plate 106 are connected, and this connecting portion 133 is as follows.

That is, at the outer end of the piston 105, the piston 105
A cylindrical connecting member having a rectangular cross section that is perpendicular to the sliding direction of the lock plate 106 is fixed, and a hook-shaped portion that is approximately C-shaped and is provided on the piston 105 side of the lock plate 106 is attached to the lock plate 106 in the sliding direction of the piston 105. The first connecting member is surrounded by a gap along the length thereof, and thereby the lock plate 106 and the piston 105 are connected with a gap between them.

Furthermore, the timing cam 1 is installed in the rocker shaft 7) 124.
25 are provided, and this timing cam 125 is
The timing cam follower 126, which has a substantially cylindrical shape, is configured to largely slide outward in the radial direction of the rocker shaft 124 when the swing of the arm 102 reaches its maximum or its vicinity (the cam lift reaches its maximum or its vicinity). has been done.

Further, the timing plate 109 is connected to the rocker arm 10.
The groove 104 is rotatably supported on a shaft attached to the main body of the cylinder 104, and is provided at the upper part of the outside of the cylinder 104.
The piston 105 is configured to be able to slide inside the piston 105 and engage with a notch 105a provided above the left end portion of the piston 105 in the drawing and the intermediate portion thereof.

Furthermore, the timing plate 109 is biased by a spring in the piston engaging direction, and when pushed upward in FIG.
6, it is rotated and brought into and out of engagement with the piston 105. Note that the oil chamber 110 of the cylinder 104 in the actuator 103 is connected to the rocker arm 102.
Regardless of the swing of the supply oil passage 122 by the oil passage 111,
The oil passage 123 in the rocker shaft 124 is constantly connected to the oil passage 123 through the rocker shaft 124.

Since the lock plate 106 and the actuator 103 that drives it are configured as described above, when pressure oil is supplied to the actuator 1 (13), the lock plate 106 is made to protrude at the required timing, causing the lock plate 106 to widen. The gap 106b is located above the plunger 113, so that the plunger 113 can slide within the cylinder 112 as the rocker arm 102 swings, thereby realizing the valve stop state.

Furthermore, when the oil is discharged from the actuator 103, the lock plate 106 is retracted at a required timing by the action of the return spring 107, and is positioned above the narrow opening 106a of the a7 plate 106 or the plunger 113. As a result, the plunger 113 is locked to the lock plate 106 and released by realizing the valve operating state.

Further, a hydraulic pressure supply system that supplies high oil pressure is provided to the oil passage 123, and the pump 51 supplies hydraulic oil from the oil tank 52 to the oil passage 123 through the oil passage 53.

The oil passage 53 has an oil control valve (O
CV) 50 is interposed, and the solenoid 50a is connected to an OCv control means M1. Air-fuel mixture increase control means M2. Actuator control means M3. When receiving a control signal from the controller 29 constituting the fuel supply amount setting means M4 and the fuel increase control means M5, 0CV50 is turned ON.
) to bring the oil passage 53 into communication, and when the solenoid 50a does not receive a control signal from the controller 29, the 0CV50 is turned OFF and the pressure oil in the oil passage 123 is transferred to the oil passage 54. discharge to.

Further, reference numeral 121 in FIG. 2 indicates a valve spring 120.
Shows the spring retainer for.

By the way, the controller (computer) 29 is equipped with a microprocessor (CPU) as a main control unit, and the output from the A/D converter is input to this microprocessor via a pass line, and the The frequency-divided output of the air 70-sensor 16 from the circuit, the output of the 02 sensor 22 (this output is actually supplied via a comparator), and the output of the rotational speed sensor 17 are input.

The microprocessor multiplies the basic data by a correction coefficient based on the information from each sensor 17 to 28 to determine the fuel injection pulse width Tout, and calculates the fuel supply to the engine combustion chamber in this way. It has the function of a fuel supply amount setting means M4 for setting the fuel supply amount, and when the high load state of the engine is detected for a set time of 18 or more and the supply air temperature At is detected to be equal to or higher than the set value Ts, the above-mentioned The fuel supply amount setting means M4 takes priority over the fuel supply amount setting means M4 so that more fuel is supplied to the combustion chamber than the supply amount set by the fuel supply amount setting means M4, that is, the air-fuel ratio C becomes rich. It has the function of a control means M5 for controlling the fuel injection valve 9.10.

The microprocessor then sends the control output to a timer circuit with three timers via a normal line (
I will do it. Here, the two timers are set at the fuel injection valve 9°1.
0, and turns on and off the solenoid coils of the fuel injection valves 9 and 10.

The timer is used to trigger the control means M5.

By the way, if we take the engine output as the vertical axis and the engine speed as the horizontal axis, there are various operating modes for this Ennon.

Then, the microprocessor multiplies the basic data by an appropriate correction coefficient depending on the operating mode and outputs desired fuel injection pulse width Tout information to the timer circuit.

In addition, [71 (front/torque opening) of the throttle valve 11
A throttle sensor 20 for all detection is provided, and the throttle sensor 20 may be a potentia meter or the like that generates a voltage proportional to the front throttle opening.

Further, as shown in FIG. 1, a water temperature sensor 21 is provided for detecting the cooling water temperature as the warm-up temperature of the engine E, and the engine speed is detected by, for example, an ignition sensor obtained from the primary negative terminal of the ignition coil 32. A rotation speed sensor 17 that detects pulse information is provided.

Furthermore, a vehicle speed sensor 24 is provided which detects the vehicle speed using a pulse signal having a frequency proportional to the vehicle speed, and a known reed switch 5 is used as the vehicle speed sensor 24.

Further, a cranking switch 26 is provided as a cranking sensor that detects the engine cranking state, and this cranking switch 26 is turned on (closed) when the starter motor is turned on, and turned off (open) otherwise.
This is the switch.

By the way, the air 70-sensor 16 detects the number of Karman vortices generated by a columnar body disposed in the intake passage 1 by using ultrasonic modulation means or by detecting a change in resistance value. 1) It detects the amount of intake air in the intake passage 1, and the digital output from the air sensor 16 is input to the controller 29. Note that the digital output from the air sensor 16 is applied to, for example, a 1/2 frequency divider within the controller 29, and then subjected to various processing.

In general, the air 70-sensor 16 malfunctions due to intake pulsation when the engine E is at low speed and under high load.In addition, an intercooler 8 is installed downstream of the air 70-sensor 16, which malfunctions due to intake pulsation, etc., when the engine E is in a low-speed, high-load state. Since pulsation almost no longer occurs, it is considered that the measurement reliability or accuracy by the air flow sensor 16 is sufficiently high.

Furthermore, in addition to the above-mentioned sensors and switches, an intake air temperature sensor 18 that detects the intake air temperature is also provided. Atmospheric pressure sensor 19 that detects atmospheric pressure. 02 sensor 22 that detects the oxygen concentration in exhaust gas,
Knock sensor 23 for detecting the engine knock state; Crank angle sensor 27 for detecting the crank angle by photoelectric conversion means with a distributor 33. Reference opening degree of the throttle valve 11 (this opening degree is, for example, engine speed 60)
Rod 15 with actuator 12 corresponding to 6) which is set as a small opening corresponding to before and after Orpm
A motor position switch 28 as a position sensor for detecting the position (reference position) is provided, and signals from these sensors and switches are input to a controller 29.

As shown, it is provided behind the rear end surface of the rod 15, and is configured to be on (closed) when the rod 5 is in the most retracted state, and off (open) at other times.

In addition, the intake air temperature sensor 18. Atmospheric pressure sensor 19. Water temperature sensor 21. Throttle sensor 20,02 sensor 22. Since the detection signal of the knock sensor 23 is an analog signal, it is sent to the controller 2 via an A/D converter.
9.

Note that the atmospheric pressure sensor 19 may be incorporated into the controller 29.

Further, an ignition coil 32 is provided, and the primary side current of the ignition coil 32 is switched on and off by a power transistor 30 as a switching transistor.

Furthermore, a display meter 35 is provided in the vehicle interior.

This display meter 35 may have a diagonal display section 35a, or a segment display section 351 in which light emitting diodes (LEDs) are arranged in a row and these LEDs blink as appropriate.
Possible examples include those with .

By the way, the controller 29 is configured with a CPU, memory (including a map), and appropriate input/output interfaces. Under the set condition I (when the engine speed is smaller than a predetermined value in the state of Under another set condition II at the time of state detection, the idle switch 252 rotation speed sensor 17 .
Throttle sensor 20. It has the function of an idle control means that receives detection signals from the vehicle speed sensor 24 and outputs an idle control signal based on these detection signals to the motor 13 of the actuator 12.

In addition, when performing rotation speed feedback control,
When performing position feedback control by changing the target engine speed as shown in FIG. 7 according to the cooling water temperature, the target throttle opening degree is changed as shown in FIG. 8 according to the cooling water temperature.

Furthermore, the driving time Δ of the motor 13 of the actuator 12
The relationship between D and the deviation ΔN or ΔP is shown in Section 9.
It is as shown in Figure 10. Here, the deviation ΔN means the difference between the actual engine speed and the target engine speed, and the deviation AP means the difference between the actual throttle opening and the target throttle opening.

This condition (■) refers to a case where at least the following items are satisfied, and refers to a condition in which the engine is relatively stable.

(1) A predetermined period of time has elapsed after the idle switch 25 was turned from off to on.

(2) The vehicle speed must be extremely low (for example, 2.5 km/h or less).

(3) The deviation of the actual engine rotational speed (actual rotational speed) from the target rotational speed is within a predetermined range.

(4) For vehicles equipped with a cooler, the cooler load should be 1" or 11".
The time ftfl must have elapsed.

Moreover, the above-mentioned condition (2) refers to a condition in which the above-mentioned condition I is not satisfied, the engine is relatively unstable, and it is desired to quickly control the feed pump.

Since the fuel control device for a compound intake type engine of the present invention is configured as described above, the fuel injection pulse width setting 70- as the fuel supply amount setting means M4 and the fuel increase control means M5 is set as shown in FIG. When the key switch is turned on, S is reset in memories L, M, and S, which is triggered by the interrupt of each ignition signal. (Intake air amount) A q r Supply air temperature At, cooling water temperature T
W.

Engine speed N-R, throttle opening PR, rate of change (acceleration information M(PR)/dt, oxygen concentration in exhaust 0
2 and idle switch on/off information l5WI are read.

Next, in step A2, it is determined whether the idle switch 25 is on, that is, whether the throttle opening is fully open.

If the idle switch 25 is off (throttle/nottle valve 1
1 is open), in step A5, the basic injection pulse width τb is set according to Aq (supply air amount). This pulse width τb is determined by dividing the output of the air flow sensor 16 as appropriate depending on the operation mode (this frequency division ratio may be fixed depending on the operation mode, but it may also be changed). ), the output signal of the rotational speed sensor 17 is used.

Next, in step A6, various correction coefficients K I
...K11 (month is set for warm-up correction coefficient, outside temperature correction coefficient, etc.)

Next, in block KK, the switching fuel increase coefficient K
The setting of p is performed.

That is, in step A7, it is determined whether the memo January - is zero, and since the initial value of memory L is zero, it is then determined in block AA whether the value of memory J is zero (step A8). ), here again memory L
Since the initial value of is zero, the process proceeds to step A9.

In step A9, the value of memory M is set to Ml (≧0,
In this case, it is determined whether it is equal to 2), and since M=0, it reaches step AIO, and further takes the YES route and determines that the switching from the P area to the P+S area has been performed ( In steps All, A12) and step A13, M=1 is set, and the fuel increase coefficient Kp is
1" (step A14).

In other words, no fuel increase is performed, and at the other times,
It is indicated by the symbol T1 in FIGS. 12(a) to (h).

Note that when switching from the P+S area to the P area or when switching is not performed, the setting of the memory M is not performed and the process proceeds to step A14.

Then, in the next ignition pulse (time T2), the determination is NO in step AIO, and the contents of memory M are added by one to become "2" (step A15).
The fuel increase coefficient Kp remains at "1" (step A14).

Furthermore, in the next ignition pulse (time T,), it is determined that M=M1 in step A9, so YES
Step A16 to reset the memory M via the route
), the value of memory L is set to the set value N (here, 2), step A17), the value of memory J is set to [1] (step A18), and the value of memory S is set to the increased fuel value K. (〉1
) (step A19).

Next, the fuel increase value Ko is set to ρ as the fuel increase coefficient (step A20).

Furthermore, in the next ignition pulse (time T,), Li2 is determined in step A7, and then in step A21, the value in the memory L is subtracted, and the value of the fuel increase coefficient Kp is set to the increase fuel value K. to be maintained.

In the next ignition pulse (time T5), the same process as in time T4 is performed, and L=N-2=0, and in the next ignition pulse (time T6), the YES route is taken from step A7. Then, in step A8, the value of memory j is determined, and since J=1, in step A22, the value of memory l)S is subtracted by a width of Δ.

In step A23, it is determined whether the value of the memory S is less than 1. If it is 1 or more, in step A24, the subtracted value of the memory S (Ko>S≧1
) is set as the fuel increase coefficient Kp.

At each α pulse (times T7 to T9), the same process as at time T6 described above is performed, and the value in the memory S is subtracted by a width of Δ.

When the value of the memory S becomes less than 1 at the ignition pulse at time TIo, the process proceeds to step A25 via the YES route.
Reset the value in memory J and set the value of +) in the fuel increase coefficient to "1".

Time T. Thereafter, the value of the fuel increase coefficient Kp is held at "1" until the switching from P→P+S is performed.

In this way, in block KK, the value of fuel increase coefficient Kp is appropriately determined within the range of 1 to Ko.

Then, after processing block KK, step A261
Here, the fuel injection pulse width Tout is set to satisfy the following equation.

Tout=rbXK, XK2X...XKIIXK
I) Note that when the idle switch 25 is on, the first
In step A3 of Fig. 3, NR≧N5I (NSI:
If NR≧NSI, it is determined in step A4 whether TW≧TWS (TWS; positive predetermined value).

If the conditions at step A3 and step A4 are negative, step A5 is executed next. Also, if the condition in step A4 is true, the first
In step A27 of FIG. 3, the fuel injection pulse width To
Set ut to τd (τd: 0 or a very small value).

This allows a so-called fuel cut or a state close to this to be achieved.

Next, the flow of processing by the CV control means M1 is shown in FIG. 14, and this processing flow is caused by an interrupt for each ignition pulse.

That is, first, in step B1, various data (engine speed NR, throttle valve opening PR) are input, and then based on this data, it is determined whether or not it is in the P region (
Step B2).

If it is a P region, 0CV50 is turned on in step B3, and if it is a P+S region, 0CV50 is turned off in step B4.

In this way, as shown in FIGS. 12(,) to (11), the state shifts from the state in which only the primary intake valve 40 is operating to the state in which the primary intake valve 40 and the secondary intake valve 41 operate. In the state where the switching signal (
Reference time: 1st pulse) occurs [see Figure 12(b) 1, when 0CV50 turns off at the required timing [
Refer to FIG. 12(c) 1, which is a cylinder in the intake process [see FIG. 12(d)].

The amount of air taken into this cylinder by the primary intake valve 40 and the secondary intake valve 41 changes as shown in FIGS. 12(e) and 12(f), respectively, and is supplied to the combustion chamber.

As shown in FIG. 12(g), the fuel increase coefficient Kp is increased from the third pulse and shifts from the ignition pulse and EGR map to the P map to the P1S map.

Then, the amount of fuel is increased in this way, and sufficient fuel is also sent to the secondary intake system 1S (see Fig. 5) leading to the secondary intake valve 41, thereby maintaining the predetermined air-fuel ratio A/F. The air-fuel mixture is supplied to the combustion chamber.

The air-fuel mixture thus appropriately adjusted is exploded (time T6) at the ignition timing indicated by the P+S map.

Then, from time T6 to time TIO, the fuel decreases stepwise, so sufficient fuel is sequentially sent to the secondary intake system IS leading to other cylinders to maintain the predetermined air-fuel ratio A/F. The air-fuel mixture is supplied to the combustion chamber.

After time T IO, fuel increase correction is no longer necessary and is therefore not performed.

By the way, if the delay in switching operation for stopping the valve is greater than the delay in increasing the supply of fuel to the combustion chamber, the oCv control means M1 is executed according to the processing flow shown in FIG. 15.

In other words, at the start, memory R is reset (20)
In step C1, after various data (engine speed NR, throttle opening PR, cooling water temperature TW, etc.) are input, the response delay during normal operation (delay in valve stop switching operation, etc.) is taken into consideration. Then, the number of ignition pulses R1 corresponding to the delay time is set in advance, and compared with the value in the memory R (step C2), switching between P and P+S (see Fig. 11).
It is determined whether or not this has occurred (steps C3 and C4),
At the time of this determination, the content of the memory R becomes "1" (step C5), and the current on/off state of 0CV50 is maintained (step C6).

Then, with the next ignition pulse, R≠R in step C2.
1 (that is, when m<R1), from step C3 N
In step C7, the contents of the memory R are increased (+1) via the o route, and the ocvs.

The current operating state is maintained (step C6).

In this state, in step C2, R
This is repeated until =R1.

When R=R1, the contents of the memory R are reset (step C8), and it is determined whether the operating region is in the P region (step C9), and since it is in the P region at the time of engine startup, No. The OC 50 is turned on via the route (step Cl0), and in other P+S areas, the ocvso is turned off via the No route (step C11).

Moreover, instead of counting the ignition pulses as shown in FIG. 15, a flow of processing based on the actual elapsed time as shown in FIG. 16 may be used, in which the timer is set to zero. In this case, a down counter is used to hold that value.

In addition to setting the fuel injection pulse width Tout in consideration of the operation delay of 0CV50 as described above,
Block AA shown in Figure 3 may be replaced with block AA' shown in Figure 17, and in this replaced processing flow, a valve stop mechanism with almost no delay in the operation of ○CV50 is used. .

Note that this example shows an example in which the engine is applied to a four-cylinder engine, but the same process can be applied to an engine with the same number of cylinders.For example, in a six-cylinder engine, the fifth From the seventh pulse, an increase in fuel is corrected, and the increased fuel amount is supplied to the intake passage at a timing determined based on the shape of the intake passage and the arrangement of the fuel supply device, and from the seventh pulse, an explosion occurs. It is done and done.

In this way, when the operating range shifts from operating only the primary intake valve to operating the primary intake valve and secondary intake valve, the idling opening of the throttle valve will change from when only the primary intake valve is operating. It becomes larger than the idling opening.

Note that switching between the P area and the P+S area shown in FIG. 11 is configured to be instructed by two maps. →P+S switching and P+
It is also possible to set the engine speed-output condition by changing the engine speed-output condition when switching from S to P.

That is, this overlapping part acts as a hysteresis zone - for example, at the same output, P-I
The engine speed at the time of P+S switching is set to be higher than the engine speed at the time of P+S→P switching.

This hysteresis zone is set by the cooling water temperature TW.
may be limited to outside when the water temperature is higher than the set water temperature TWS, and further,
In consideration of prevention of hunting due to rotational fluctuations during sudden acceleration, a confirmation time (t2 seconds; t2<B) may be adopted for zone determination.

Furthermore, after P-+P+sP+, reswitching may be prohibited for a certain period of time to stabilize the operating state of the valve operation stop mechanism M'.

When the key switch is turned off, the current of the oil pump 51 is turned on for 41 seconds, and the 0CV50 is turned on to stop the operation of the secondary intake valve 41. Startability may be ensured by setting the P state to stop.

Further, by using an injector type fuel supply means, the amount of air-fuel mixture can be controlled without controlling the opening degree of the throttle valve.

In this embodiment, a pair of electromagnetic fuel injection valves 9 with different capacities are used.
．． If), the fuel injection valve 9 and the injection valve 10 may be operated at all times, and the fuel injection amount may be controlled by controlling the injection time width, or the injection valves 9 and 10 may be switched as necessary.

〔Effect of the invention〕

As detailed above, according to the fuel control device for a composite intake engine of the present invention, the primary intake system has a primary intake valve that operates over the entire operating range, and a primary intake system that has a primary intake valve that operates over the entire operating range. A compound intake type engine having a secondary intake system having a secondary intake valve with a valve operation stop mechanism, comprising a fuel supply means for supplying fuel to the intake passage of the engine, when the secondary intake valve is stopped. The simple structure includes a fuel increase control means for temporarily increasing the amount of fuel supplied to the intake passage before switching from the primary intake valve and the secondary intake valve to operation. The air-fuel ratio of the air-fuel mixture in the passage becomes appropriate, and it is possible to reliably prevent engine output fluctuations and shocks during switching.

[Brief explanation of the drawing]

The figure shows a fuel control system for a composite intake type engine as an embodiment of the present invention.
Figure 2 is a configuration diagram showing the valve operation stop device of the engine valve system, Figure 3 is a partial plan view of the lock plate, and Figure 4 is a partial plan view of the lock plate.
The figure is a configuration diagram of the main parts, Fig. 5 is a vertical sectional view of the main parts of the engine, Fig. 6 is a plan view schematically showing the main parts of the engine, and Figs. 7 to 11 and 12 (,) -(h) are all graphs for explaining the effect, and FIGS. 13-17 are all flowcharts for explaining the effect. 1.Intake passage, IP..Primary intake system, 1S..Secondary intake system, 2..Exhaust passage, 3..Turbocharger, 4.
・Turbine, 5...Compressor, 6...Wastegate valve, 7...Pressure response device, 8...Intercooler,
9,1.0...Electromagnetic fuel injection valve, 11...Throttle valve, 11a1...Shaft, 11c...Throttle lever, 11
d...One end of throttle lever, 12...Actuator, 13...Motor, 14a...Tsohm, 14b...Worm wheel, 14c...Pipe shaft, 14d...Female thread part, 15...Rod, ISa... Male thread part, 151]
・・Long size, 16・・Air 70-sensor, 17・・Rotation speed sensor, 18・・Intake temperature sensor, 19・・Atmospheric pressure sensor, 20・・Throttle sensor, 21・・Water temperature sensor, 2
2...02 sensor, 23...tank sensor, 24...vehicle speed sensor, 25...idle switch as idle sensor, 26...cranking switch, 27...crank angle sensor, 28...motor motion switch,
29...controller, 3o...power transistor,
31... Catalytic converter, 32... Ignition coil, 33... Distributor, 34... Electromagnetic switching valve, 35... Display, 35a... Oblique display, 35I]
...Segment type display section, 36..Ignition key switch, 37..Battery, 40.Yuji intake valve, 41
・・Secondary intake valve, 42・・Exhaust valve, 50・・Oil control valve (OCV), 50a・・Tre/id,
51...Pump, 52...Oil tank, 53.54...
・Oil passage, 101...Cam, 102...Rocker arm, 1
03... Actuator, 1 (14... Crank, 10
4a...Groove, 1()5...Piston, 1()5a...Notch, 106...Lock plate, 106a...Narrow gap section, 106b...Wide gap section, 107...Return spring, 108... Spring receiver, 109...Timing plate, 110...Oil chamber, 111...Oil passage, 112...Cylinder, 112a...Long hole, 113...Plunger, 11
4. Spring, 119. Secondary intake valve, 119a.
・Stem for secondary intake valve, 120...valve spring,
121... Spring receiver, 122, 123... Oil path, 124
--Rocker shaft, 125...Timing cam, 12
6. Timing cam follower, 133. Connection part between lock plate and piston, E. Engine, EN.
・Latching mechanism, M′ ・・Valve operation stop mechanism, Ml・・OC
v control means, M2...air mixture increase control means, M3...actuator control means, M4...fuel supply amount setting means,
M5: fuel increase control means, s1 to S4: cylinders. Agent Yoshihiko Iinuma Patent Attorney Figure 6 Figure 7 ↑ Water temperature → Figure 8 ↑ Eye = 20 0 20 30 40 Water temperature → Figure 9 U, ΔN (actual rotation speed - target rotation speed) Figure 10 ΔP (actual rotation speed) degree - target opening degree) Fig. 14 Fig. 15 Fig. 16 Fig. 17

Claims (1)

[Claims] A composite intake system that has a primary intake system with a primary intake valve that operates over the entire operating range, and a secondary intake system that has a secondary intake valve with a valve operation stop mechanism that operates in some operating ranges. In the type engine, a fuel supply means for supplying fuel to the intake passage of the engine is provided, and before the switching from the time when the secondary intake valve is stopped to the time when the primary intake valve and the secondary intake valve are activated, the above-mentioned A fuel increase control means for temporarily increasing the amount of fuel supplied to the intake passage is provided.
Fuel control device for compound intake type engines.