JP2782651B2 - Engine control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine for fully opening the throttle opening at a full opening when the throttle opening of the engine is fully open, the ignition timing at the full opening is delayed from the ignition timing at the full opening. The present invention relates to an engine control device for driving ignition control means and air-fuel ratio control means to enrich the air-fuel ratio at a predetermined amount in the engine so as to ensure durability when the engine is fully opened.

[0002]

2. Description of the Related Art Conventionally, engines mounted on vehicles and the like are:
When the throttle opening is fully opened, high load operation is started. In particular, when the engine speed reaches a high rotation range, the engine reaches a high load high rotation zone, and the engine enters a severe driving state. If the engine continues to operate in such a high-load high-speed zone for a long time, the engine quickly decreases its durability, and the normal driver can stop such high-load high-speed operation in a short time. There are many. Further, there is a configuration in which the engine protection during such a high-load high-speed rotation is also performed by an engine control system.

That is, as a logic for securing the durability when the engine is fully opened, when the throttle opening of the engine reaches the fully opened state, the ignition timing at the fully opened state is delayed by a predetermined amount from the ignition timing at the fully opened state, and the engine is fully opened. There is a method in which the air-fuel ratio in the fully opened state is made richer by a predetermined amount than the air-fuel ratio in the front opening degree. In this case, the engine output can be reduced by a predetermined amount by an ignition retard process that delays the ignition timing by a predetermined amount. When the air-fuel ratio is made rich by a predetermined amount, the combustion chamber is cooled by the excess fuel supply, and the engine output is reduced by a predetermined amount. Can be done. As described above, in a normal engine, the output of the throttle opening is suppressed to be lower than that of the opening before full opening to ensure engine durability.

[0004]

However, such output reduction processing at the throttle opening is set in preparation for continuous operation of the engine in a high-load high-speed zone.
For this reason, when driving in a high-load, high-speed zone is performed transiently, this is wasteful processing. In particular, in a vehicle where it is desired to increase the power performance, the output reduction processing logic is directly installed. It has been a problem whether it is effective to ensure engine durability or to eliminate the output reduction processing at the throttle opening where transient operation is the mainstream and to improve the output during transition.

An object of the present invention is to provide an engine control device that can operate the engine in a high-power mode in a high-load and high-speed zone without reducing the durability of the engine.

[0006]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides an ignition control means for controlling an ignition timing of an engine to a target ignition timing according to engine operation information, and an air-fuel ratio of the engine. Air-fuel ratio control means for controlling the target air-fuel ratio according to the engine operation information; and, when the throttle opening of the engine is fully open, the ignition timing at full opening is delayed by a predetermined amount from the ignition timing at the opening before full opening, and the engine is fully opened. A full-open mode command for enriching the air-fuel ratio at full opening to a predetermined amount from the air-fuel ratio at the previous opening, or an output boost angle amount obtained by advancing the ignition timing at full opening by a predetermined amount and the air-fuel ratio at full opening to a predetermined amount Output control means for outputting an output increase mode command adopting a lean output increase air-fuel ratio to the ignition control means and the air-fuel ratio control means, wherein the output control means has a high engine operation range. Upon detection of the rushed from the zone outside the operation range in zone operation range in load high rotation zone and performs the output increasing mode predetermined driving time, after a predetermined number of times embodiment of the output increasing mode, predetermined disabled time the output increasing mode Is prohibited.

[0007]

SUMMARY OF Upon detecting that the engine operating region by the output control means has entered from the zone outside the operation range in zone operating region of high load and high rotation zone, the output enhancement angle the ignition timing by a predetermined RyoSusumu angle at fully opened Since the output increase mode adopting the output and the air-fuel ratio in which the air-fuel ratio at full open is increased by a predetermined amount is performed for a predetermined drive time, the output during transient can be improved for a predetermined drive time, When the power increase mode is performed a predetermined number of times, the output increase mode is prohibited for a predetermined prohibition time, so that a decrease in engine durability can be prevented.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The engine control device shown in FIG.
It is mounted on a cylinder engine (hereinafter simply referred to as engine E). The intake passage R of the engine E includes an intake branch pipe 1, a surge tank 4 connected thereto, an intake pipe 2 and an air cleaner 3 integrated with the tank. The intake pipe 2 has a throttle valve 6 pivotally supported therein. The axis of the throttle valve 6 is connected to an accelerator pedal (not shown) outside the intake path R. The throttle valve 6 is provided with a return spring (not shown) for urging the throttle valve 6 in the closing direction, so that the throttle valve 6 is closed when the tensile force of an accelerator cable (not shown) is weakened. The throttle valve 6 is provided with a throttle opening sensor 9 for outputting a throttle opening θs signal of the throttle valve 6 and an idle switch 8 for outputting idle information.

On the other hand, an intake bypass passage 101 bypassing the throttle valve 6 is provided with an idle speed control (ISC) valve 7 for idle control, and the valve 7 is provided with a spring 70.
1 and is driven by a stepper motor 702. Further, the intake passage R is provided with an intake air temperature sensor 11 that outputs information on the intake air temperature Ta. Further, the engine is provided with a water temperature sensor 12 for detecting a cooling water temperature as a warm-up temperature of the engine and a knock sensor 15 for outputting knock information. Further, the engine crankshaft is provided with a crank angle sensor 13 (also used for calculating the engine speed Ne) that outputs a unit crank angle signal Δθ. Further, a battery (not shown) is provided with a battery sensor 14 for detecting a battery voltage VB.
The surge tank 4 is provided with a negative pressure sensor 16 that outputs information on the intake pipe pressure Pb. Each of these sensors outputs a detection signal to an ECU 17 described later.

An injector 18 is mounted on each of the intake ports which can communicate with each cylinder of the engine E, and the fuel whose constant pressure is adjusted by a fuel pressure adjusting means 19 is supplied to each of the injectors 18 from a fuel supply source 20, and the fuel is injected. The control is performed by the ECU 17. Further, an ignition plug 21 is attached to each cylinder facing portion in the cylinder head, and each ignition plug 21 is connected to an ignition drive circuit 22.
The ignition drive circuit 22 is connected to the ECU 17. The ignition drive circuit 22 here includes a timing control circuit in the ECU 17 and an open / close drive circuit on the igniter side. Each of these open / close drive circuits is connected to each power transistor for controlling the open / close timing and the energizing time. The ignition coil is connected to the ignition plug 21 of each cylinder at the target ignition timing θb, and ignition is performed.

Engine control unit (ECU)
A main part 17 is formed by a microcomputer, and controls a fuel injection amount of the engine E, an ignition timing control process and other known controls. In particular, the ECU 17 here
As shown in FIG. 2, the ignition controller A1, the air-fuel ratio controller A2, and the output controller A3 have the following functions.

The ignition control means A1 controls the ignition timing of the engine E to a target ignition timing θadv according to the engine operation information (for example, the engine speed Ne and the intake pipe negative pressure Pb). The air-fuel ratio control means A2 controls the air-fuel ratio A / F of the engine E to a target air-fuel ratio (A / F) o according to the operation information of the engine. When the throttle opening θs of the engine E is fully open, the output control means A3 delays the ignition timing θor at the full opening θs _MAX by a predetermined amount from the ignition timing θo1 at the full opening θs1 before the opening, and the air-fuel ratio at the full opening θs1 ( A / F)
A full-open mode mf command for enriching the air-fuel ratio (A / F) r at a full-open θs _MAX by a predetermined amount from 1 is supplied to the ignition control means A1.
And the air-fuel ratio control means A2, in particular, when it is detected that the engine operating range has reached the in-zone operating range within the high-load high-speed zone Z1 from the out-of-zone operating range, the ignition timing at full open is advanced by a predetermined amount. The output increase mode mp adopting the angled output increase angle θp and the output increase air-fuel ratio (A / F) p in which the air-fuel ratio at full open is made a predetermined amount leans for a predetermined time in the operation zone outside the zone Z1. Perform a predetermined amount each time.

Here, an engine control apparatus according to an embodiment of the present invention will be described with reference to control programs shown in FIGS. The ECU 17 starts the control in the main routine by turning on a key switch (not shown). Here, first, each function is checked, an initial function set such as an initial value set is performed, then various kinds of operation information of the engine are read, and then the process proceeds to step a2. Then, an operating range is calculated from the engine speed N and the intake pipe negative pressure Pb as load information. From the operation range map of FIG.
At step a3, the air-fuel ratio feedback FLG is cleared, the fuel cut FLG is set to 1, and the routine returns.

On the other hand, if it is determined in step a2 that the fuel cut is not within the fuel cut range and the process reaches step a5, the fuel cut FLG is cleared, and it is determined whether the air-fuel ratio feedback condition is satisfied. Z
At the time of the transient operation range as described in 1) or before the completion of the warm-up, in step a7, the air-fuel ratio correction coefficient KMAP corresponding to the current operation information (Pb, Ne) and the warm-up increase correction corresponding to the cooling water temperature Tw. The coefficient Ka is calculated from an appropriate warm-up increase correction coefficient calculation map, these values are stored in the address KAF, and the high load / high rotation zone Z1 is set, and the process proceeds to step a10. If the air-fuel ratio feedback condition is satisfied from step a6, the target air-fuel ratio (A / F) o according to the current operation information (Pb, Ne) is calculated, and the fuel amount correction coefficient K _FB that can achieve the air-fuel ratio is calculated. I do. Step a fuel amount correction coefficient K _FB is stored in a9 the address KAF, reaches step a10.

Here, the other fuel injection pulse width correction coefficient KDT and the correction value TD of the dead time of the fuel injection valve are used.
Is set in accordance with the operating conditions, and further, each correction coefficient used for calculating the ignition timing θadv is calculated. Here, the correction value is calculated by differentiating the water temperature correction value θwt to be advanced in accordance with the water temperature drop and the throttle valve opening θs to obtain a differential value Δ
There is an acceleration retardation -θacc corresponding to θs, an intake air temperature correction value θat advanced in accordance with a decrease in intake air temperature, a knock retardation -θk value in accordance with an increase in the knock signal Kn, and a conduction time in accordance with a decrease in the battery voltage VB. Is also calculated, and the process proceeds to step all.

In step a11, a dwell angle is calculated and set by a predetermined dwell angle calculation map so that the dwell angle increases in accordance with the engine speed Ne. After that, other known control is performed, and the process returns. At a predetermined crank angle 180 ° position in the middle of this main routine, the ignition timing calculation routine of FIG. 7 is executed. Here, steps d1, d2
Takes in the intake pipe negative pressure Pb and the engine speed Ne,
The basic ignition timing θb corresponding to these values is calculated according to a predetermined basic ignition timing calculation map (preset).

When the process reaches step d3, the basic ignition timing θb, the water temperature correction value θwt, and the intake air temperature correction value θat are fetched, and the acceleration retard-θacc and the invalid retard-
The retard amount θret obtained by the addition of θreto is calculated, and then the target ignition timing θad is calculated by equation (1).
Calculate v. .theta.adv = .theta.b + .theta.wt + .theta.at-.theta.ret (1) Thereafter, in step d4, a predetermined retard amount -.theta.k is fetched according to the amount of the knock signal Kn, and the target ignition timing .theta.adv is corrected to the retard side. Return to the main routine. Note that the knock retard map is set in advance. Next, the ignition control process in the middle of the main routine will be described with reference to FIG.

The ignition control routine of FIG. 10 is based on the fact that the reference signal θo changes from OFF to ON every time the crank angle reaches 75 ° (75 ° BTDC) before top dead center (crank angle 180 °) in the middle of the main routine. It is executed by interrupting the main routine. In step c1, predetermined data is fetched, and when step c2 is reached, the latest target ignition timing θt and the latest dwell angle are set in the ignition drive circuit, and the process returns to the main routine. Here, in all the operation modes, ignition of each cylinder is performed by driving an ignition drive circuit, and each ignition drive circuit is driven every time a crank angle of 90 ° elapses to perform an ignition process near a compression top dead center.

The injector driving process shown in FIG. 8 is performed during the main routine. In steps b1 and b2,
Intake air amount A according to in-cylinder pressure Pb and engine speed Ne
/ N, the latest engine speed Ne is obtained from the crank angle pulse period, and the process proceeds to step b3. Here, it is determined whether or not the fuel cut flag FCF = 1. If the flag is on, the process returns to the main, and if the flag is off, the process proceeds to step b4. Here, the basic fuel pulse width Tf is calculated from the intake air amount A / N using a Tf calculation map, and further, the air-fuel ratio correction coefficient KAF, the atmospheric temperature and atmospheric pressure correction coefficient KDT, and the injector operation delay correction value taken from the main routine side. A known fuel pulse width Tinj corresponding to the target injector drive time is calculated by TD or the like, the target fuel pulse width Tinj is set to the driver for driving the injectors 18 of all the cylinders, and each driver is triggered and returns in step b7. Processing is taking place.

Further, the operation zone control routine of FIG.
This is executed by interruption for a predetermined time Δt1 in the middle of the main routine. Here, when step s1 is reached,
The latest engine speed Ne and the latest intake pipe negative pressure Pb are taken in, and in step s2, it is determined whether the engine operating range is within the high-load high-speed zone Z1 or not.
Exceeds the set high rotation speed Ne1, and the latest intake pipe negative pressure Pb
Is higher than the set high load Pb1, it is determined that MPFLG = 1 in the high load high rotation zone Z1, and the process proceeds to step s3. Otherwise, the process returns as MPFLG = 0. In step s3, only when the timer MPTIM and the timer ZnTIM are initialized, they are reset to 0, respectively, and the process proceeds to step s4. The timer MPTIM, the timer Z1TIM, and the after-mentioned outer timer Z1TIM are constantly counted in a predetermined timer count routine.

In step s4, the elapsed time from the previous entry into the high-load high-speed zone Z1 is taken in from the timer Z1TIM, and the elapsed time is set to the set elapsed time T2 (set in advance).
If it exceeds the value, the process proceeds to step s5. After the lapse of time, the process reaches step s5. Here, while the number of _inrushes N _Z1 to the high-load high-speed zone before the set elapsed time T2 does not exceed two, the process proceeds to step s6. ) Go to step s9. In step s6, the output increase mode m is set in the high load / high rotation zone Z1.
p, MPFLG = 1, an output enhancement angle amount θp obtained by advancing the ignition timing at full opening by a predetermined amount, and the ignition control is performed with this output enhancement angle amount θp in step d.
6, the target ignition timing θadv = θp is processed, and further, the air-fuel ratio (A / F) p in which the air-fuel ratio at full open is made lean by a predetermined amount is selected, and this output air-fuel ratio (A) is selected. /
F) In order to perform the fuel injection control at p, the air-fuel ratio correction coefficient KMAP is set to the output air-fuel ratio (A / F) in the process of step b7.
The correction coefficient KMAPP corresponding to p is set, and the following fuel injection processing is performed.

Thereafter, in step s7, the timer MPTI
It is determined whether or not the time width of M has exceeded the drive time T1 (set in advance). Before the elapse , the elapse is waited, and when elapse, the process proceeds to step s8, where the process is performed in one output increase mode mp. Is completed, and MPFLG = 0 is returned. On the other hand, at step s5, this time is the time t-2 (FIG.
(See (b)), the process proceeds to step s9, where MPFLG is cleared to 0 assuming that the vehicle is outside the zone Z1, and the external timer Z n TIM is reset when it is not reset to 0. As a result, the processing (θadv = θp, KMAP = KMAPP) in the output increase mode mp is stopped, and the process proceeds to step s10. Here, it is determined whether or not the elapsed time width outside the high-load and high-speed zone Z1 exceeds the prohibition time T3.
The output increase mode mp is prohibited, MPFLG is set to 0, and processing in the output increase mode mp (θadv = θp, KMAP = K
MAPP) continues to be stopped ((ta + tb + tc)> T
(Region 3), and when the prohibition time T3 has elapsed, the process directly returns to the main routine from step s10. This step s
When the output increase mode mp is prohibited by the processing of 10, s11
Is prohibited only during T3, and sets the ignition timing θor in fully open [theta] s _MAX normal throttle opening [theta] s is delayed a predetermined amount than the ignition timing θo1 in some fully opened before opening θs1 fully open during this time, fully opened before opening Air-fuel ratio at degree θs1 (A /
F) The full-open mode mf, which is to set the air-fuel ratio (A / F) r at the full-open θs _MAX enriched by a predetermined amount from 1 is executed by a well-known full-open mode mf processing routine (not shown).

Therefore, the output of the engine E is regulated by the well-known full-open mode mf processing, the engine E is operated, its durability can be ensured, and the engine E can be operated a predetermined number of times.
After the power increase mode , the prohibition time T3 , which is a predetermined time, elapses
If the, again only the during the set elapsed time T2, the driving time processing in the output increasing mode mp of within T1 (θadv = θ
p, KMAP = KMAPP) can be performed twice, and in that case, operation at high load and high speed can be performed, and the output characteristics of the engine can be improved. In the above, the output control means A3 performs the output increase mode twice a predetermined number of times.
After, if the elapsed inhibition time T3 which is a predetermined time, again, reaches a high load and high rotation zone Z1, the driving time T
The processing in the output increase mode mp within 1 was possible twice. Instead, as shown in FIGS. 4 (a) and 4 (b), when the vehicle reaches the high-load high-rotation zone Z1, the output increase mode mp during the driving time T1 is set to a predetermined number of times. The operation is performed once, the operation in the output increase mode mp is prohibited for the set elapsed time T2 'after the zone exits, and the elapsed time t-5
To reset the control and re-execute the high-load high-speed zone Z1 again.
A mode may be used in which the same control is repeated when the distance reaches the inside. In this case, the same operation and effect can be obtained.

[0024]

As described above, according to the present invention, when the engine operating range reaches the in-zone operating range within the high-load high-speed zone from the out-of-zone operating range , the ignition timing in the fully opened state for a predetermined driving time is advanced by a predetermined amount. The output increase mode that uses the angle of the output increase angle and the output increase air-fuel ratio in which the air-fuel ratio at full open is made a predetermined amount can be executed a predetermined number of times.
And after a predetermined number of implementations,
Inhibit time The output increase mode is prohibited, so engine durability
Can be prevented from decreasing.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an engine control device as one embodiment of the present invention.

FIG. 2 is an explanatory diagram of functions of an engine control device of FIG. 1;

3A is a waveform diagram of an operation range of the engine control device of FIG. 1, and FIG. 3B is a waveform diagram of a time limit when an output increase mode mp is selected.

FIG. 4A is a waveform diagram of an operation range of an engine control device according to another embodiment of the present invention, and FIG. 4B is a power increase mode m of the device.
FIG. 7 is a waveform diagram of a p selection time period.

FIG. 5 is a characteristic diagram of an operating range map adopted by the control device of FIG. 1;

FIG. 6 is a flowchart of a main routine executed by an ECU of the control device of FIG. 1;

FIG. 7 is a flowchart of an ignition timing calculation routine performed by an ECU of the control device of FIG. 1;

FIG. 8 is a flowchart of an injector driving routine performed by an ECU of the control device of FIG. 1;

FIG. 9 is a flowchart of an operation zone control routine performed by an ECU of the control device of FIG. 1;

FIG. 10 is a flowchart of an ignition control routine performed by an ECU of the control device of FIG. 1;

[Explanation of symbols]

 Reference Signs List 6 throttle valve 9 throttle opening sensor 13 crank angle sensor 16 intake pipe negative pressure sensor 17 ECU 18 injector 21 ignition plug 22 ignition control circuit Vc current control signal θadv target ignition timing A1 ignition control means (A / F) o target air-fuel ratio A2 air-fuel ratio control means mf full open mode A2 air-fuel ratio control means A3 output control means Z1 high load high rotation zone θp output increase angle (A / F) p output increase air-fuel ratio mp output increase mode T3, T2 predetermined time

Claims (1)

(57) [Claims] An ignition control means for controlling an ignition timing of the engine to a target ignition timing according to the engine operation information; and an air-fuel ratio control means for controlling the air-fuel ratio of the engine to a target air-fuel ratio according to the operation information of the engine. When the throttle opening of the engine is fully open, the ignition timing at full opening is delayed by a predetermined amount from the ignition timing at full opening, and the air-fuel ratio at full opening is richer than the air-fuel ratio at full opening by a predetermined amount. Or a power increase mode command that employs an output increase angle amount obtained by advancing the ignition timing at the full open position by a predetermined amount and an output increase air-fuel ratio obtained by leaning the air-fuel ratio at the full open position by a predetermined amount. and an output control means for outputting to the ignition control means and the air-fuel ratio control means, said output control means, out of zone operation range in zone operating region of the engine operating region is a high load and high rotation zone Upon detecting that the rushed and performs the output increasing mode predetermined driving time, after a predetermined number of times embodiment of the output increasing mode, the engine control system and inhibits a predetermined inhibit time the output increasing mode.