JPS61126372A - Ignition-timing controller for engine - Google Patents

Abstract

PURPOSE:To improve the driving performance and the output by installing an ignition control means which receives the output of an aimed ignition-timing setting means for setting an aimed ignition-timing and ignites a spark plug at the aimed ignition-time. CONSTITUTION:An aimed throttle-valve opening-degree setting means sets the aimed throttle-valve opening-degree of an engine by receiving the output of an acceleration detecting means. An aimed ignition-timing setting means receives the output of the aimed throttle-valve opening-degree setting means and sets an aimed ignition-timing according to the aimed throttle-valve opening-degree. An ignition control means receives the output of the aimed ignition-timing setting means and ignites a spark plug at the aimed ignition-timing. Since the ignition timing can be favorably controlled in good response in accordance with the variation of the operation state of the engine, the driving performance and the output in the transient operation of the engine can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an engine ignition timing control device, and in particular to an engine ignition timing control device that controls the throttle valve opening (i.e., The present invention relates to an ignition timing control device that electrically controls the amount of intake air.

(Prior Art) Conventionally, as a technology for controlling the air-fuel ratio of the engine to a predetermined air-fuel ratio with respect to the accelerator operation amount indicating the required engine output,
As shown in Japanese Unexamined Patent Publication No. 57-65835, an accelerator detecting means for detecting the amount of accelerator operation, and a device receiving the output of the accelerator detecting means adjust the air to be supplied to the engine so that a preset air-fuel ratio is achieved. A target throttle valve opening setting means for setting a target value, that is, a target throttle valve opening, and a throttle receiving the output of the target throttle valve opening setting means and controlling the opening of the throttle valve to achieve the target throttle valve opening. and a drive means, which determines the target throttle valve opening (that is, the target air amount) according to the accelerator operation amount, and controls the throttle valve opening so that the target throttle valve opening is achieved. Are known.

By the way, the ignition timing of an engine has a great effect on the engine's operating conditions, especially its drivability and output.
The ignition timing is generally determined based on the intake air amount of the engine, which is obtained by detecting the intake pressure, for example, and is corrected based on the engine rotational speed.

However, if the engine ignition timing is determined based on the current intake air of the engine such as the intake pressure, there will be a considerable delay in response to changes in engine operating conditions, especially when the engine is operating in a transient region. This is undesirable in terms of performance and output improvement.

(Object of the invention) The present invention has been made in consideration of the above-mentioned circumstances.
It is an object of the present invention to provide an ignition timing control device for an engine that can control ignition timing with good response in response to changes in engine operating conditions.

(Structure of the Invention) The present invention is based on the premise that the intake air amount of the engine, which is a basic element for determining the throttle valve opening, that is, the target ignition timing, is electrically controlled in accordance with the accelerator operation amount. The target ignition timing of the engine is set based on the target throttle valve opening set according to the accelerator operation amount. Specifically, as shown in FIG. 1, there is provided an accelerator detecting means for detecting the amount of accelerator operation, and a target throttle valve opening setting means for receiving the output of the accelerator detecting means and setting a target throttle valve opening of the engine. and a throttle drive means that receives the output of the target throttle valve opening setting means and drives the throttle valve to set the throttle valve opening to the target value, and receives the output of the target throttle valve opening setting means; target ignition timing setting means for setting a target ignition timing according to a target throttle valve opening; ignition control means for receiving an output from the target ignition timing setting means and igniting a spark plug at the targeted ignition timing; This is a configuration equipped with the following.

With such a configuration, the ignition timing is determined by widening the target throttle valve opening corresponding to the predetermined target air amount, so that changes in the air amount can be quickly dealt with.

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

FIG. 2 shows the overall configuration of an engine control device according to an embodiment of the present invention, where 1 is, for example, a four-cylinder engine, and 2 is an engine with one end opening to the atmosphere via an air cleaner 3 and the other end opening to the engine air. An intake passage 4 supplies intake air to the engine 1, and an exhaust passage 4 has one end open to the engine 1 and the other end opened to the atmosphere to discharge exhaust gas from the engine 1. Reference numeral 5 indicates an accelerator pedal that is depressed in accordance with the engine output request, and reference numeral 6 indicates a throttle valve that is disposed in the intake passage 2 and controls the amount of intake passage. There is no linkage relationship, and as in IT, it is electrically controlled by the amount of depression of the accelerator pedal 5, that is, the amount of accelerator operation. Reference numeral 7 denotes a throttle actuator comprising a step motor or the like that opens and closes the throttle valve 6.

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

On the other hand, reference numeral 12 denotes a fuel injection valve disposed downstream of the throttle valve 6 in the intake passage 2 to inject and supply fuel. The fuel tank 16 is connected to the fuel tank 16 through the fuel tank 16, and the fuel is supplied from the fuel tank 16, and the surplus fuel is returned to the fuel tank 16 via the fuel pressure regulator 17 or the turn passage 18. Therefore, fuel at a predetermined pressure is supplied to the fuel injection valve 12 6. In addition, 19 is an accelerator pedal position sensor as an accelerator detection means for detecting the amount of depression of the accelerator pedal 5, that is, the accelerator operation amount α; 20 is an air flow meter disposed upstream of the throttle valve 6 in the intake passage 2 to detect the intake air amount QaR; 21 is an intake air temperature sensor 22 disposed upstream of the throttle valve 6 in the intake passage 2 to detect the intake air temperature; 23 is a throttle position sensor that detects the opening degree of the throttle valve 6, and 23 is the engine coolant temperature T.
A water temperature sensor 24 for detecting W is disposed upstream of the catalyst device 8 in the exhaust passage 4 and detects the air-fuel ratio input of the engine 1 from the oxygen concentration component in the exhaust gas. The detection signals of these 19 to 24 are input to a control unit 25 consisting of an analog computer, etc., and the control unit 25 controls the throttle actuator 7, solenoid valve 11, and fuel injection valve 12. Ru. Furthermore, an igniter 26 is connected to the control unit 25, and a signal of the number of ignitions, that is, the engine rotation speed Ne is inputted, and as described later, the igniter 26 is set to ignite at a predetermined timing. A timing signal is output. Also,
The above control unit 25 includes a destination repeater 2.
7 and a battery 28 are connected as inputs, and input signals of ignition timing and battery voltage VB, respectively.

Of course, the ignition signal from the igniter 26 is outputted as a secondary current supply to the spark plug 33 via the destroyer 27, and the spark plug 33 is ignited.
constitutes the ignition control means.

Next, the operation of the control unit 25 is divided into throttle control, fuel control, and ignition timing control.

Note that FIG. 3 shows the case of a four-cylinder engine.

Throttle control In FIG. 3, first, the throttle valve opening control system will be described. MA1 is a target value Qa1 of air supplied to the -71 engine 1 so that the air-fuel ratio is set in advance for the accelerator operation amount α. is set, and receives the output from the accelerator pedal position sensor 19,
A target air amount setting means 29 is configured to set a target air amount Qa1 to be supplied to the engine 1 in accordance with the accelerator operation amount α. MA2 is a second map in which the minimum air amount Q a m is set to provide the air-fuel ratio necessary for idle up with respect to the engine coolant temperature TW, and receives the output from the water temperature sensor 23; Engine coolant temperature T1
1, the minimum air amount Qam for water temperature correction is set. 30 receives the respective outputs of the first map MA1 (target air amount setting means 29) and the second map MA2, and calculates the target air amount Qa determined by the first map MA1.
This is a maximum value selection circuit that selects the maximum value Qaz between t and the minimum air quantity Qam for water temperature correction found in the second map MA2, and the target air quantity Qax is the minimum air quantity Qam for water temperature correction. When the engine temperature is lower than 1, the minimum air amount Q am for water temperature correction is selected in order to increase the idle, thereby ensuring good engine operability. Further, MA3 is a third map in which the maximum air amount Qam determined by the engine speed Ne is set for the engine speed Ne, and the maximum air amount Qam is set according to the engine speed Ne. I have to. 31 receives each output of the maximum value selection circuit 30 and the third map MA3, and indicates the maximum air amount Qa determined by the maximum value selection circuit 30.
Maximum air 11 determined by 2 and 3rd map MA3 Q
This is a minimum value selection circuit that selects the minimum value Qa3 from a M, and the target air amount Qa1 is the engine rotation speed N.
When the maximum air amount QaM determined by
M is selected to limit the maximum value. As described above, the target air amount Qa3 is determined for the accelerator operation amount α, taking into account the correction for the engine coolant temperature TW and the correction for the maximum air amount at full throttle valve opening determined by the engine speed Ne.

Furthermore, 32 is a divider that receives the output from the minimum selection circuit 31 and divides the target air amount Qa3 by a value (N e X 2) that is twice the engine speed Ne. The intake air amount AC1 per cylinder is calculated.

MA4 is the target value intake air amount Ac for the engine speed Ne
This map MA4 receives the output from the divider 32 and sets the throttle valve opening θ1 that should be the target value of intake air amount Ac1. That's what I do. Reference numeral 34 denotes an intake air amount feedback correction module which receives a signal of the target intake air amount Ac1 from the divider 32, and also receives signals of the actual air amount QaR and the engine rotation speed Ne actually measured by the air flow meter 20, and A feedback coefficient CaFB for comparing the actual intake air amount AcR per cylinder calculated based on the air amount QaR and the engine speed Ne with the target intake air amount Ac1, and feedback-correcting the throttle valve opening according to the deviation. is calculated.

Further, 35 receives each output from the fourth or fifth map MA4 and the intake air amount feedback correction module 34, and calculates the target throttle valve opening θ1 obtained from the map MA4 by the intake air amount feedback correction module 34. The signal of the target throttle valve opening θ2 corrected by the multiplier 35 is outputted to the throttle actuator 7, and the opening of the throttle valve 6 becomes the target throttle valve. The opening degree is controlled to θ2.

As described above, the throttle drive means 36 receives the output of the target air amount setting means 29 and controls the throttle valve 6 to set the air amount to the target value, that is, to set the opening degree of the throttle valve 6 to the target value. ing.

Fuel control Next, regarding the fuel supply amount control system in FIG. Target fuel setting means 37, which is a fifth map in which a value Qf1 is set, receives the output from the accelerator pedal position sensor 19, and sets a target fuel amount Qfx to be supplied to the engine 1 according to the accelerator operation amount α). It consists of MB6 is the sixth map in which the minimum fuel amount Q f m is set for the engine cooling water temperature TW so that the air fuel ratio required for idle up is obtained for the air amount Q a m set in the S2 map MA2. And,
Upon receiving the output of the water temperature sensor 23, the engine coolant temperature Tl
The minimum fuel amount Qfm for water temperature correction is set according to l. 3
8 is the fifth map MBS (target fuel amount setting means 37).
) and the outputs of the sixth map MB6, the target fuel amount Qf1 determined by the fifth map MBS and the sixth map MB
This is a maximum value selection circuit that selects the maximum value Qf2 from the minimum fuel amount Qfm for water temperature correction found in step 6, and when the target fuel amount Qfl is less than the minimum fuel amount Qfm for water temperature correction, the idle up Therefore, the minimum fuel amount Qfm for water temperature correction is selected to ensure good engine operability. Also, MB7 is the third map MA3 mentioned above.
A seventh map in which the maximum fuel amount c) - fpq for the engine speed Ne is set so that the maximum air amount QaM becomes a preset target air-fuel ratio with respect to the maximum air amount QaM set at the engine speed Ne. The maximum fuel amount QfM is set accordingly. 39 receives each output of the maximum value selection circuit 38 and the seventh map MB7, and selects the maximum fuel amount Qf2 determined by the maximum value selection circuit 38 and the maximum fuel amount QfM determined by the seventh map MB7. This is a minimum value selection circuit that selects the minimum value Qf3, and when the target fuel amount Qf1 exceeds the maximum fuel amount Qf determined by the engine speed Ne, that is, as described above, the target air amount Qax is determined by the engine speed Ne. When the target value is an amount that exceeds the determined maximum air amount QaM and is more than the amount of air that can be taken in when the throttle valve 6 is fully open, the maximum air amount QaM is selected so that the air-fuel ratio becomes the target air-fuel ratio even at that time. ing.

From the above, as in the case of air volume, accelerator operation amount α
, the target fuel amount Qf3 takes into account the correction for the engine coolant temperature TW and the maximum fuel amount when the throttle valve 6 is fully open, which is determined by the engine speed Ne.
is found.

Then, the target fuel amount Qf from the minimum value selection circuit 39 is
The three signals are a divider 40, first to third dividers 41 to 43,
It is output to the fuel injection valve 12 via the twin unit cut switch 44 and the fuel injection valve correction circuit 45. The divider 40 receives the output from the minimum value selection circuit 39, and divides the target fuel amount Qf3 by the engine rotational speed Ne, assuming that fuel is injected into two cylinders at the same time, to obtain the fuel supply amount per cylinder Qff. It is calculated. Further, the first multiplier 41 calculates the target fuel supply amount Qf determined by the divider 40.
i is the water temperature correction coefficient CTWO for the engine cooling water temperature Tw obtained in the eighth map MBg and the enrichment correction coefficient CE obtained in the enrichment correction module 46.
The target fuel supply amount Qfi is calculated by performing multiplication correction by R. This enrichment correction module 46 is based on a zone signal from a zone determination module 50, which will be described later.
When the intake air amount Ac1 relative to the engine speed Ne is in the enrich line region, the fuel supply amount is, for example, -8%.
To increase the amount, use the enrichment correction coefficient CER (for example, 1.08
) is output.

Further, the second multiplier 42 multiplies and corrects the target fuel supply amount Qfiz obtained by the induction multiplier 41 by the learning correction coefficient CSTD obtained by the fuel learning correction module 47 to obtain the target value fuel supply ff1Qfi2. It is calculated. This fuel learning correction module 47 adjusts the fuel feedback correction conditions in the fuel feedback correction module 48 based on the zone signal from the zone determination module 50 and the fuel feedback correction coefficient CfFB signal from the fuel feedback correction module 48 (described later). For example, when 2 seconds or more have passed after the establishment of the formula, set the fuel learning correction coefficient C5TD to its initial value = 1.0, and then calculate the following formula (% peak value of %B + bottom value of CFFB of the past 8 times)/16
-1.0) is sequentially updated and output.

Further, the third multiplier 43 multiplies and corrects the target fuel supply amount Qf i2 obtained by the second multiplier 42 by the fuel feedback correction coefficient CfFB obtained by the fuel feedback correction module 48 to obtain the target fuel supply amount Qfi3. is calculated.

This fuel feedback correction module 48 operates based on the zone signal from the zone determination module 50 and the air-fuel ratio input frame from the O2 sensor 24, for example, under the following conditions: Engine cooling water temperature TW>60°C ■Intake air amount Acl≧Cylinder stroke volume 10%■ The intake air amount Ac1 with respect to the engine speed Ne is outside the enrich line and the twin cut zone.

(2) The 02 sensor 24 is active.

When the fuel feed rate is satisfied, the fuel feedback correction coefficient CFFB (for example, 0.8≦
It outputs CfFB≦1.25, proportionality constant P=0.06, and integral constant I=0.05/5ec).

Further, the twin cut switch 44 is controlled to open and close by an output signal from a twin cut control module 49. Based on the zone signal and target intake air amount Acl signal from the zone determination module 50, the twin air cut control module 49 operates under the following conditions, for example: ■Engine coolant temperature TW>60°C ■Intake air amount Act<10% of cylinder stroke volume■ When the engine rotational speed Ne>1100Orp is satisfied, the unit control switch 44 is controlled to be opened to cut fuel injection. Here, the above-mentioned scene determination module 50 determines the engine rotation speed Ne, the target intake air amount Ac1
, engine coolant temperature Tl1l, and air-fuel ratio input signals to create condition determination signals (zone signals) for each of the control modules 46 to 49.

Furthermore, the fuel injection valve correction circuit 45 includes the third fuel injection valve correction circuit 45.
receiving the target fuel supply gr-Q fi3 signal from the multiplier 43 and the battery voltage VB signal from the battery 28;
The pulse signal as the target fuel supply amount signal to the fuel injection valve 12 is corrected according to the battery voltage VB, and the fuel injection valve 1
This is what is output to 2. As described above, the fuel injection valve 1
2 is driven for a predetermined period of time in synchronization with ignition, and constitutes a fuel control means 51 configured to control the predetermined fuel supply amount to a target value.

In FIG. 3, numeral 52 is an ignition timing control module that serves as a means for determining target ignition timing.
Each signal of aR is input, the target ignition advance angle is determined based on these signals θx and Ne, and the final ignition is determined by correcting this target ignition advance angle by the actual air amount QaR. The signal is output to the igniter 26 when the angle is advanced.

The function of the ignition timing determining module 52 will be explained with reference to FIG. 4. First, in step 61, a target advance angle 5AOr is determined from a predetermined map based on the throttle opening θ1 and the engine rotational speed Ne. Next, in step 62, the actual air amount Q output from the air flow meter 20 is
After determining aR, in step 63, the retardation correction value TPC
Find S. This retardation correction value T PCS is (actual air i
It is obtained by multiplying the calculated value of 1 Q a R - target air ffcQa3) by the target air amount Qa3 by a predetermined advance angle correction coefficient KSA. Then, in step 64, the final target advance angle 5A02 is divided by subtracting the retard angle correction value TPCS from the target advance angle 5AO1.

After this, in step 65, the time Ku necessary for the crankshaft of engine l to rotate 1 degree from engine speed Ne is determined.
T is calculated. Then, in step 66, from 60@ to S
Find 5AO3 by subtracting Ao, 2, and calculate this 5
Multiply AO3 by KuT, the time required for the above crankshaft to rotate 1 degree, and get 5AO2 from BTDC60".
The time required to reach TMWAIT is calculated.
i
After the TMWAIT calculation in step 66 described above, it is determined in step 67 whether or not the BTDC has reached 60'. If the BTDC is not 60', this determination is repeated. When the BTDC has reached 60", the determination is made in step 68. The timer TMWAIT is set (time t1 in FIG. 5). After this, in step 69, it is determined whether or not the timer is up, that is, whether TMWAIT has elapsed. If the timer is not up, this determination is repeated. , when the timer is up (5th [ff1t
2), the ignition cylinder is identified in step 70 and ignition is performed for the predetermined cylinder. Of course, this ignition is performed by supplying the secondary current generated by the igniter 26 cutting off the primary current at time t2 in FIG. 5 to the ignition plug 33.

In this way, the ignition timing is determined in accordance with the target air amount determined in accordance with the accelerator operation amount, so that the optimum ignition timing can be obtained in response to changes in the air amount.

Note that when the control unit 25 is configured by a microcomputer, it may be of either an analog type or a digital type. Further, as a representative value of the target throttle valve opening degree, in addition to θ1, Acl shown in FIG. 3 or θ2 may be used.

(Effects of the Invention) As is clear from the above description, the present invention can control the ignition timing without delay in response to changes in the amount of air supplied to the engine.

As a result, driving performance is improved during excessive engine operation,
Alternatively, something advantageous from the standpoint of output, etc. can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. FIG. 2 is an overall system diagram showing one embodiment of the present invention. FIG. 3 is a block diagram showing a control example of the present invention. FIG. 4 is a flow chart showing three control examples of the present invention. FIG. 5 is an explanatory diagram showing the relationship between the ignition advance angle and the crank angle. 1: Engine 2: Intake passage 5: Accelerator pedal 6: Throttle valve 7: Throttle actuator 19: Position sensor 25: Control unit 26: Igniter 27: Distributor 36: Throttle drive means 52 2. Ignition timing determination module: Le

Claims (1)

[Claims] (1) Accelerator detection means for detecting the amount of accelerator operation; Target throttle valve opening setting means for receiving the output of the accelerator detection means and setting a target throttle valve opening of the engine; and Target throttle valve opening setting means Throttle driving means receives the output of the target throttle valve opening and drives the throttle valve to set the throttle valve opening to the target value; and receives the output of the target throttle valve opening setting means and sets the target ignition timing according to the target throttle valve opening. A target ignition timing setting means for setting a target ignition timing, and an ignition control means for receiving an output from the target ignition timing setting means and igniting a spark plug at the target ignition timing. Timing control device.