JPH11343953A - Acceleration time ignition timing control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress too much lag of ignition timing, stabilize combustion and prevent lowering of an engine output by setting final ignition timing by performing a spark advance correction for basic ignition timing by water temperature correction amount and controlling the final ignition timing so as not to exceed a lag limit value when a throttle operating condition is formed. SOLUTION: A control means 124 performs a spark advance correction for basic ignition timing set by engine speed and load of an engine 2 by water temperature correction amount set according to at least of a cooling water temperature, determines final ignition timing and controls ignition timing of the engine 2. An acceleration time ignition timing control device 122 limits the final ignition timing so as not to exceed a lag side limit value when an operating condition of a throttle valve 20 in the engine 2 is formed by a control means 124. As a result, too much lag of ignition timing is suppressed in an operating state in which load is transiently increased although engine speed does not rise much, that is, in an operating state like starting acceleration time after a cold staring, in particular.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition timing control apparatus at the time of acceleration, and more particularly, to an ignition timing control apparatus at the time of acceleration capable of preventing the backlash during starting acceleration after cold start of the engine and improving drivability. About.

[0002]

2. Description of the Related Art Some engines mounted on vehicles and the like include an ignition timing control device for controlling the ignition timing. The ignition timing control device obtains the final ignition timing by correcting the basic ignition timing set according to the operating state of the engine with various correction amounts, and controls the ignition timing of the engine so that the final ignition timing is reached.

[0003] As such an ignition timing control device, there is one disclosed in Japanese Patent Application Laid-Open No. 6-26431. According to this publication, when it is determined that the ignition timing is in a retard correction range such as when the engine is warmed up, a basic retard amount required for increasing the temperature of the catalyst is calculated, and the basic retard amount is calculated. By correcting the amount in accordance with the throttle opening and obtaining the basic ignition timing based on the corrected retard amount, the torque characteristic variation with respect to the throttle opening can be obtained even during ignition timing retard control. The catalyst is activated at an early stage while ensuring a good driving feeling without any trouble.

[0004]

In the conventional ignition timing control device, the basic ignition timing IGTST is set according to the operating state of the engine, for example, the engine speed and the engine load as shown in FIG. Timing IGTS
When T is variously corrected, for example, as shown in FIG. 3, when the cooling water temperature is low, the water temperature correction amount IGTTTW is advanced to correct the ignition angle to obtain the final ignition timing IGTF.
Some control the ignition timing of the engine so as to be F.

[0005] Since the knocking hardly occurs when the engine is cold, the ignition timing is advanced to improve the fuel efficiency and the drivability.

However, as shown in FIG. 8, when starting and accelerating after a cold start with a low cooling water temperature, the combustion state when the cooling water temperature at the start is low is lower than the combustion state at the time of complete warm-up. Since the engine load is not stable, the engine load becomes high, and there is a problem that the engine load enters a region a indicated by oblique lines in FIG.

In such a state, if the ignition timing enters the region a before the engine speed increases, the ignition timing is retarded due to an increase in the engine load, and the combustion becomes more unstable. As a result, the engine output is reduced, the increase in the engine speed is slowed down, and there is a disadvantage in that hesitation occurs.

In this case, the conventional ignition timing control device
Although the advance correction shown in FIG. 3 is performed when the cooling water temperature is low as described above, the advance correction using the water temperature correction amount IGTTTW is set based on the engine speed and the engine load shown in FIG. The basic ignition timing IGTST is performed over the entire range.

For this reason, if the advance angle correction based on the water temperature correction amount IGTTTW is set so as to prevent the backlash even in the area a of FIG. 2, the advance angle based on the water temperature correction amount IGTTTW is also applied to other areas. Since the correction is performed, the ignition timing in other areas is excessively advanced, and there is a disadvantage that fuel efficiency is deteriorated and output is reduced.

[0010]

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned disadvantages, the present invention sets the basic ignition timing set by the operating state of the engine at least by a water temperature correction amount set according to the cooling water temperature. In the ignition timing control device for controlling the ignition timing of the engine so as to obtain the final ignition timing by performing the advance correction and obtaining the final ignition timing, when the throttle operation condition of the throttle valve of the engine is satisfied, the final ignition timing is determined. A control means for controlling the ignition timing so as not to exceed the retard side limit value is provided.

The control means may be arranged such that when the operating state of the engine is a non-idle operating state and the throttle operating condition of a throttle valve of the engine is satisfied, the final ignition timing exceeds the retard side limit value. The retarding side limit value is set according to the cooling water temperature.

When the throttle opening of the throttle valve is within a set opening range, the control means determines that the throttle operating condition is satisfied, and the amount of change in the throttle opening per unit time of the throttle valve is set. If the degree of change exceeds the degree of change, it is determined that the throttle operation condition is satisfied, and the throttle opening of the throttle valve is within the set opening range, and the amount of change of the throttle opening per unit time of the throttle valve corresponds to the set degree of change. If it exceeds, it is determined that the throttle operation condition is satisfied.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The ignition timing control apparatus according to the present invention is arranged such that, when the throttle operating condition of the throttle valve of the engine is satisfied, the final ignition timing does not exceed the retard side limit value by the control means. By controlling the engine, it is possible to suppress the ignition timing from being excessively retarded in an operation state in which the engine load transiently increases even though the engine speed does not increase so much, stabilizing the combustion and reducing the engine output. Can be prevented.

The control means is arranged to prevent the final ignition timing from exceeding the retard side limit value when the operating state of the engine is a non-idle operating state and the throttle operating condition of the throttle valve of the engine is satisfied. Control, and by setting the retard side limit value according to the cooling water temperature, particularly in an operating state such as at the time of starting acceleration after the cold start.
It is possible to suppress the ignition timing from being excessively retarded, stabilize combustion, and prevent a decrease in engine output.

The control means determines that the throttle operating condition is satisfied when the throttle opening of the throttle valve is within the set opening range, and determines the amount of change in the throttle opening per unit time of the throttle valve to the set opening. When the change amount exceeds the change amount, it is determined that the throttle operation condition is satisfied, and when the throttle opening of the throttle valve is within the set opening range and the change amount of the throttle opening per unit time of the throttle valve exceeds the set opening change amount. By judging that the throttle operation condition is satisfied, the control that suppresses excessive retardation of the ignition timing by appropriately determining the operating state where the engine load transiently increases even though the engine speed does not increase so much Can be implemented.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 7 show an embodiment of the present invention. In FIG. 7, reference numeral 2 denotes an engine. The engine 2 has an air cleaner 4, an intake pipe 6, a throttle body 8, a surge tank 10, an intake manifold 1 as an intake system.
2 and the intake passage 14 is provided. The air cleaner 4 is provided with an intake air temperature sensor 16. The intake pipe 6 is provided with an intake air amount sensor 18. The throttle body 8 is provided with a throttle valve 20 and the throttle sensor 2 is provided.
2 are provided.

The engine 2 includes an exhaust manifold 24, an exhaust pipe 26, a catalytic converter 28, a rear exhaust pipe 30 as an exhaust system, and an exhaust passage 32. The exhaust manifold 24 is provided with a first O2 sensor 34. The catalyst converter 28 is provided with a catalyst 36, and the catalyst 3
A second O2 sensor 38 is provided on the downstream side.

This engine 2 is provided with a fuel injection valve 40. The fuel injection valve 40 is connected to a fuel tank 44 by a fuel supply passage 42. In the fuel tank 44,
A level sensor 46, a tank internal pressure sensor 48, and a fuel pump 50 are provided. The fuel in the fuel tank 44 is pressure-fed to the fuel supply passage 42 by the fuel pump 50, dust is removed by the fuel filter 52, and supplied to the fuel injection valve 40.

The fuel supply passage 42 is provided with a fuel pressure adjusting valve 54 for adjusting the fuel pressure. The fuel pressure adjusting valve 54 adjusts the fuel pressure to a predetermined value by the intake pressure introduced from the pressure guiding passage 56 communicating with the intake passage 14, and returns excess fuel to the fuel tank 44 through the fuel return passage 58.

The engine 2 is provided with two evaporative fuel devices 60 and 62. The first evaporative fuel device 60 includes:
The canister 64 is provided, and the canister 64 and the fuel tank 4 are provided.
An evaporative passage 66 communicating with the evaporative passage 4 is provided.
Is provided with a tank internal pressure adjusting valve 68.

The first evaporative fuel device 60 has a purge passage 70 communicating the canister 64 with the intake passage 14 on the downstream side of the throttle valve 20, a purge control valve 72 is provided in the purge passage 70, and the canister 64 is provided with a purge control valve 72. An atmosphere passage 74 communicating with the atmosphere is provided.

The second evaporative fuel device 62 is provided with a canister 76, an evaporative passage 78 communicating the canister 76 with the fuel tank 44, and a tank internal pressure regulating valve 80 in the evaporative passage 78. The tank internal pressure regulating valve 80 is provided with a pressure control valve 84 and an intake pressure sensor 86 in a pressure passage 82 communicating with the intake passage 14.

The second evaporative fuel device 62 includes a canister 76 and the purge passage 7 of the first evaporative fuel device 60.
0, and a purge passage 88 communicating with the purge passage 88 is provided.
A purge control valve 90 is provided in the engine, and an evaporative diagnostic passage 92 is provided for communicating a purge passage 88 closer to the canister 76 with respect to the purge control valve 90 and the intake passage 14 upstream of the throttle valve 20. 94 are provided.

Further, the second evaporative fuel device 62 has an atmosphere passage 96 communicating the canister 76 with the atmosphere, and an atmosphere opening / closing valve 98 in the atmosphere passage 96.

The engine 2 has an EGR passage 100 communicating the exhaust passage 32 and the intake passage 14, and an EGR control valve 102 in the EGR passage 100. Reference numeral 104 denotes a blow-by gas passage, reference numeral 106 denotes a PCV valve, reference numeral 108 denotes an ignition coil, reference numeral 110 denotes an ignition plug, and reference numeral 112 denotes a water temperature sensor.

The engine 2 is provided with a bypass passage 114 which bypasses the throttle valve 20 and communicates with the intake passage 14, and an idle control valve 116 for adjusting the flow rate of bypass air is provided in the bypass passage 114. Bypass passage 11
6 is provided with an idle adjustment passage 118 bypassing the idle control valve 116 and an idle adjustment screw 120.

The intake air temperature sensor 16 and the intake air amount sensor 18
, Throttle sensor 22, first O2 sensor 34 and second
O2 sensor 38, fuel injection valve 40 and level sensor 46
, Tank pressure sensor 48, fuel pump 50, purge control valve 72, pressure control valve 84, intake pressure sensor 86, purge control valve 90, evaporation diagnostic valve 94, atmosphere open / close valve 98, EG
R control valve 102, ignition coil 108, water temperature sensor 112
The idle control valve 116 is connected to the control means 124 of the ignition timing control device 122 at the time of acceleration.

The control means 124 includes a vehicle speed sensor 126, a crank angle sensor 128, a range position switch 130, an air conditioner 132, and a power steering pressure switch 13.
4, a diagnostic switch terminal 136, a test switch terminal 138, a starter switch 140, a range switch 142, an ignition switch 144, a main fuse 146, and a battery 148.

The control means 124 sets the basic ignition timing IGTST based on the engine speed and the engine load shown in FIG. 2, which is the operating state of the engine 2, and sets the basic ignition timing IGTST to at least the cooling water temperature shown in FIG. The final ignition timing IGTF is obtained by performing advance correction using the water temperature correction amount IGTTW set accordingly.
The ignition timing of the engine 2 is controlled so that

The ignition timing control device 122 controls the throttle valve 20 of the engine 2 by the control means 124.
When the throttle operation condition is satisfied, control is performed so that the final ignition timing IGTF does not exceed the retard side limit value THLMTL (throttle limit Low) shown in FIG.

In this embodiment, the control means 124
Indicates that the operation state of the engine 2 is a non-idle operation state and the throttle opening THθ of the throttle valve 20 of the engine 2 is within a set opening range (TH1 <THθ <TH2).
Is established, the final ignition timing IGTF is controlled so as not to exceed the retard side limit value THLMTL set according to the coolant temperature.

Next, the operation will be described.

As shown in FIG. 1, the ignition timing control device 124 at the time of acceleration starts the engine 2 (step 20).
0), it is determined by the throttle sensor 22 whether or not the vehicle is in the non-idle operation state (step 202).

If the determination (step 202) is NO, the ignition timing IGTID at the time of idling is set (step 218), and the stop of the engine 2 is determined (step 214).
Jump to

If the judgment (step 202) is YES, the basic ignition timing IGTST is set based on the engine speed and the engine load shown in FIG. 2 (step 20).
4) The basic ignition timing IGTST is retarded (IGTST + IGTTW) by a water temperature correction amount IGTTTW set according to the cooling water temperature shown in FIG.
GTF is obtained (step 206).

Next, it is determined whether or not the throttle operation condition in which the throttle opening THθ of the throttle valve 20 is within the set opening range (TH1 <THθ <TH2) is satisfied (step 208).

If the determination (step 208) is YES, the final ignition timing IGTF is set to the retard side limit value THLMT.
L (step 210), the ignition timing is controlled so that the final ignition timing IGTF is limited so as not to exceed the retard side limit value THLMTL (step 212), and the engine 2 is stopped. It is determined whether or not it has been performed (step 214).

If the determination (step 208) is NO
In the case of, the final ignition timing IG obtained by the advance correction
The ignition timing is controlled so as to be TF (step 21).
2) It is determined whether the engine 2 has stopped (step 214).

If the determination (step 214) is NO, the process returns to the non-idle operation state determination (step 202). If the determination (step 214) is YES, the process ends (step 216).

As described above, in the ignition timing control device 122 at the time of acceleration, the operation state of the engine 2 is the non-idle operation state, and the throttle opening THθ of the throttle valve 20 of the engine 2 is set to the set opening range (TH1). <THθ <TH
When the throttle operation condition in 2) is satisfied, control is performed so that the final ignition timing IGTF does not exceed the retard side limit value THLMTL set according to the coolant temperature.

Even if the throttle opening degree of the throttle valve 20 is small, the engine 2 has a large amount of change in the throttle opening degree per unit time (throttle opening degree change rate). The transient increase in the engine load makes it easier to enter the region a in FIG. 2, and the engine output is reduced to cause a decrease in drivability.

On the other hand, when the throttle valve 20 is slowly opened to near full open when the amount of change in the throttle opening per unit time is small, it is difficult for the engine 2 to enter the region a in FIG. Without reducing the drivability.

Therefore, the throttle valve 20
If the final ignition timing IGTF is controlled not to exceed the retard side limit value THLMTL in an operation state where the throttle opening is slowly opened, as shown in FIG. Therefore, knocking occurs and the engine output decreases.

The ignition timing control device 122 for accelerating the ignition timing generates an ignition caused by an apparent increase in the engine load when the throttle opening degree change per unit time is large (rapid opening) even if the throttle opening degree is small. This is to eliminate the timing setting failure.

The transient increase in engine load due to the rapid opening of the throttle valve 20 is not actually required by the engine 2 but is an apparent one. Since the required value of the ignition timing at this time is a value close to a low load (for example, THθ = 1/4) as shown in FIG. 6, the final ignition timing IGTF does not exceed the retard side limit value THLMTL. As described above, by limiting the value that can be taken on the retard side, as shown in FIG. 5, the engine output is obtained, and the engine speed is smoothly increased.

Thus, the ignition timing control device 122 at the time of acceleration operates in an operating state in which the engine load transiently increases even though the engine speed does not increase so much, in particular, an operating state such as at the time of starting acceleration after the cold start. In this case, the ignition timing can be prevented from being excessively retarded, the combustion can be stabilized, and the engine output can be prevented from lowering.

For this reason, the ignition timing control device 1
No. 22 can prevent the backlash at the time of starting acceleration after the cold start of the engine 2 and can improve the drivability.

In this embodiment, the throttle operating condition is satisfied when the throttle opening THθ of the throttle valve 20 is within the set opening range (TH1 <THθ <TH2). The throttle opening change amount ΔTHθ per hit is the set opening change amount ΔTH1
Is exceeded (ΔTH1 <ΔTHθ), it can be determined that the throttle operation condition is satisfied, and the throttle opening THθ of the throttle valve 20 is within the set opening range (TH1 <
If THθ <TH2) and the throttle opening change amount ΔTHθ of the throttle valve 20 per unit time exceeds the set opening change amount ΔTH1 (ΔTH1 <ΔTHθ), it can be determined that the throttle operation condition is satisfied.

In particular, both the throttle opening and the throttle opening change amount are set as the throttle operating conditions (TH1 <T
When Hθ <TH2 and ΔTH1 <ΔTHθ),
Even if the throttle opening of the throttle valve 20 is small, if the amount of change in the throttle opening per unit time is large,
It is possible to more reliably determine an operation state in which the engine load is likely to easily enter the region a in FIG. 2 due to the transient increase in the engine load even though the engine speed does not increase so much, thereby stabilizing the combustion. This can prevent a decrease in engine output.

[0050]

As described above, the ignition timing control apparatus according to the present invention operates in an operating state in which the engine load transiently increases despite the fact that the engine speed does not increase so much, in particular, when starting and accelerating after the cold start. In such an operating state, it is possible to suppress the ignition timing from being excessively retarded, to stabilize the combustion and to prevent a decrease in the engine output,
Determining appropriately the operating condition where the engine load transiently increases even though the engine speed does not increase much,
Control for suppressing the ignition timing from being excessively retarded can be performed.

Therefore, the ignition timing control apparatus according to the present invention can prevent the backlash during starting acceleration after the cold start of the engine, and can improve the drivability.

[Brief description of the drawings]

FIG. 1 is a flowchart of ignition timing control at the time of acceleration showing an embodiment of the present invention.

FIG. 2 is a diagram showing a setting of a basic ignition timing based on an engine speed and an engine load.

FIG. 3 is a diagram showing a setting of a water temperature correction amount based on a cooling water temperature.

FIG. 4 is a diagram illustrating setting of a retard side limit value according to a cooling water temperature.

FIG. 5 is a timing chart showing a relationship among an engine speed, an ignition timing, a throttle opening, and an engine load according to the present invention.

FIG. 6 is a diagram showing a relationship between engine torque and ignition timing.

FIG. 7 is a timing chart showing a conventional relationship among an engine speed, an ignition timing, a throttle opening, and an engine load.

FIG. 8 is a timing chart showing the relationship among the conventional engine speed, ignition timing, throttle opening, and engine load.

[Explanation of symbols]

 2 Engine 14 Intake passage 20 Throttle valve 22 Throttle sensor 108 Ignition coil 110 Spark plug 112 Water temperature sensor 124 Acceleration ignition timing control device 126 Control means

Claims (6)

[Claims] A final ignition timing is obtained by advancing a basic ignition timing set according to an operating state of an engine by at least a water temperature correction amount set according to a cooling water temperature so as to obtain the final ignition timing. In the ignition timing control device for controlling the ignition timing of the engine, control means is provided for controlling the final ignition timing so as not to exceed a retard side limit value when a throttle operation condition of a throttle valve of the engine is satisfied. The ignition timing control device at the time of acceleration. 2. The control device according to claim 1, wherein the operating state of the engine is a non-idle operating state and the throttle operating condition of a throttle valve of the engine is satisfied.
2. The ignition timing control device according to claim 1, wherein the ignition timing is controlled so that the final ignition timing does not exceed the retard side limit value. 3. The ignition timing control device according to claim 1, wherein the control unit sets the retard side limit value according to a coolant temperature. 4. The acceleration according to claim 1, wherein the control means determines that the throttle operation condition is satisfied when the throttle opening of the throttle valve is within a set opening range. Ignition timing control device. 5. The throttle control device according to claim 1, wherein the control means determines that the throttle operation condition is satisfied when a throttle opening change amount per unit time of the throttle valve exceeds a set opening change amount. The acceleration timing control device according to claim 2. 6. The throttle operating condition when the throttle opening of the throttle valve is within a set opening range and the throttle opening change amount per unit time of the throttle valve exceeds the set opening change amount. The ignition timing control device at the time of acceleration according to claim 1 or 2, wherein it is determined that the following condition is satisfied.