JP2542490Y2 - Ignition timing control device for internal combustion engine - Google Patents

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 device for an internal combustion engine, and more particularly to an ignition timing control device for an internal combustion engine that controls ignition timing so as to avoid knocking when shifting from a low load state to a high load state. .

[0002]

2. Description of the Related Art When electronically controlling the ignition timing of an internal combustion engine, it is known to perform advance / retard control based on an engine speed and an ignition advance value set in a load state of the engine. Generally, the load state of the engine is detected from the absolute pressure of the intake pipe or the like (for example, Japanese Patent Application Laid-Open No. 57-59056).

However, in a control device that detects the engine load state from the absolute pressure of the intake pipe, when the engine is suddenly accelerated from a low rotation state or the like, the operation state of the engine is changed from the low load state to the throttle opening (θTH). ) Is greatly opened and suddenly changes to a high load state, a detection delay occurs in the absolute pressure sensor (PBA) sensor.
If the detection value of the PBA sensor is used, the ignition timing is advanced (i.e., the ignition timing on the low load side) with respect to the desired ignition timing, and there is a disadvantage that knocking easily occurs.

[0004] In order to solve the above-mentioned drawbacks, the applicant of the present application has provided an atmospheric pressure (PA) sensor, and when the above-mentioned engine operating state suddenly changes from a low load state to a high load state, As shown in FIG.
There has been proposed a control device for controlling the ignition timing by setting the ignition advance value θIG using the detection value θIGa of the PA sensor instead of the detection value θIGba of the sensor (Japanese Patent Application No. Sho 62-132).
No. 76771).

According to this control device, it is possible to prevent a delay in following the ignition timing even if the engine operation state suddenly changes from a low load state to a high load state, and to prevent occurrence of knocking. it can.

[0006]

However, in the above-mentioned conventional control device (Japanese Patent Application No. 62-76771), FIG.
As shown in the figure, after the control using the ignition advance value θIGa based on the detection value of the PA sensor is performed, the ignition advance value based on the detection value of the PBA sensor is immediately obtained when the engine speed NE reaches a predetermined speed. Since the ignition timing is controlled by shifting to θIGba, θIG of the ignition advance value θIG indicated by the point a
At the time of transition from IGa to θIGba, there is a new problem that a sudden torque fluctuation occurs, causing a shock and causing discomfort to the occupant.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and it is intended to prevent the occupant from feeling uncomfortable when the engine operation state changes from a low load state to a high load state, thereby improving driving performance. It is an object of the present invention to provide an ignition timing control device for an internal combustion engine that can contribute.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an engine rotation detecting device for detecting an engine speed.
Number detecting means, and an engine for detecting a load state of the engine.
Gin load detecting means and the engine speed detecting means.
Engine speed detected and the engine load detected
Ignition based on the engine load condition detected by the means
First ignition timing setting means for setting a timing;
Engine speed detected by the engine speed
At the time of the first ignition based on the atmospheric pressure by the atmospheric pressure detecting means
Characteristics different from the ignition timing set by the
Second ignition timing setting means for setting an ignition timing;
Throttle valve opening to detect engine throttle valve opening
Degree detecting means, and the engine speed is a predetermined engine speed.
And the throttle valve opening is less than the engine speed.
Set the first ignition timing below the corresponding predetermined throttle valve opening.
First region for setting ignition timing by means for determining
The engine speed is equal to or lower than the predetermined engine speed and
The opening of the torval valve corresponds to the engine speed.
At the time of ignition by the second ignition timing setting means that is equal to or greater than the opening degree of the torque valve
A second area for setting a period is set in advance, and the engine
The rotation speed and the throttle valve opening reach the second region.
Was set by the second ignition timing setting means immediately
Operating the engine at the ignition timing, the engine speed or
When the throttle valve opening returns to the first range
Is immediately set by the second ignition timing setting means.
The ignition timing is set by the first ignition timing setting means.
Transition control that performs transition control that gradually transitions to the ignition timing
Means .

[0009]

According to the above arrangement, the second ignition timing setting means in place of the ignition timing set by the first ignition timing setting means
After the ignition timing is controlled based on the set value, the transition control means gradually changes the control of the ignition timing by the second ignition timing setting means to the control based on the ignition timing set by the first ignition timing setting means. Transition.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an overall configuration diagram showing an embodiment of an ignition timing control device for an internal combustion engine according to the present invention.

Reference numeral 1 denotes an internal combustion engine having, for example, four cylinders (hereinafter simply referred to as "engine"). A throttle body 3 is provided in the middle of an intake pipe 2 of the engine 1, and a throttle valve 3 is provided therein. 'Is arranged. The throttle valve 3 'has a throttle valve opening degree (θTH).
A sensor 4 is connected, and outputs an electric signal corresponding to the degree of opening of the throttle valve 3 'and supplies it to an electronic control unit (hereinafter referred to as "ECU") 5.

A fuel injection valve 6 is provided for each cylinder between the engine 1 and the throttle valve 3 'and slightly upstream of an intake valve (not shown) of the intake pipe 2. Each of the fuel injection valves 6 is connected to a fuel pump (not shown) and the ECU 5
And the valve opening time of fuel injection is controlled by a signal from the ECU 5.

A branch pipe 7 is provided downstream of the throttle valve 3 ′ of the intake pipe 2, and an absolute pressure (PBA) sensor 8 is attached to a tip of the branch pipe 7. The PBA sensor 8 is electrically connected to the ECU 5, and the absolute pressure PBA in the intake pipe 2 is converted into an electric signal by the PBA sensor 8 and supplied to the ECU 5.

An intake air temperature (TA) sensor 9 is mounted on the pipe wall of the intake pipe 2 downstream of the branch pipe 7, and the intake air temperature TA detected by the TA sensor 9 is converted into an electric signal.
It is supplied to the ECU 5.

An engine water temperature (TW) sensor 10 composed of a thermistor or the like is inserted into the cylinder peripheral wall of the cylinder block of the engine 1 filled with cooling water, and the engine cooling water temperature TW detected by the TW sensor 10 is converted into an electric signal. The converted data is supplied to the ECU 5.

An engine speed (NE) sensor 11 and a cylinder identification (CYL) sensor 12 are mounted around a camshaft or a crankshaft (not shown) of the engine 1.

The NE sensor 11 outputs a signal pulse (hereinafter, referred to as a "TDC signal pulse") at a predetermined crank angle position every time the crankshaft of the engine 1 rotates by 180 degrees.
The L sensor 12 outputs a TDC signal pulse at a predetermined crank angle position of a specific cylinder, and these TDC signal pulses are supplied to the ECU 5.

The ignition plug 1 for each cylinder of the engine 1
Reference numeral 3 is electrically connected to the ECU 5, and the ignition timing is controlled by the ECU 5.

Furthermore, the atmospheric pressure (PA) sensor 14
U5, which converts the atmospheric pressure PA detected by the PA sensor 14 into a corresponding electric signal and supplies it to the ECU 5.

The ECU 5 shapes the input signal waveforms from the various sensors described above, corrects the voltage level to a predetermined level,
An input circuit 5a having a function of converting an analog signal value to a digital signal value and the like;
U "), a storage means 5c comprising a ROM for storing various calculation programs executed by the CPU 5b, a predetermined map, and the like, and a RAM for storing calculation results and the like, and the fuel injection valve 6 and the ignition plug 13. And an output circuit 5d for supplying a drive signal.

In the ignition timing control device for an internal combustion engine having the above-described structure, the CPU 5b operates in accordance with the operating state of the engine such as when the load suddenly changes from a low load state to a high load state.
Performs the ignition timing advance / delay control as appropriate based on a predetermined map stored in the storage means 5c (ROM).

FIG. 2 is a diagram showing the value of the reference valve opening (θwot) with respect to the engine speed NE. In the figure, the solid line is the boundary value of the valve opening θwot between the low load state and the high load state. 3 shows a reference valve opening (θwot) curve. Also, PBA
The area indicates an area in which the ignition advance value θIG is searched using the detection value of the PBA sensor as a parameter, and the PA area indicates the PBA
An area in which the ignition advance value θIG is searched using the detection value of the PA sensor as a parameter instead of the detection value of the sensor is shown.

[0024] As FIG. 2 As is clear from the reference valve opening θwot between a predetermined upper limit value NE ₃ of the engine rotational speed NE and the predetermined lower limit value NE ₁ increases in proportion to the engine speed NE Is set. The reference valve opening θwot is obtained by an experiment in advance at a value at which the pressure in the combustion chamber is equivalent to the atmospheric pressure at that time when the throttle valve (θTH) 3 ′ is opened at a predetermined value or more at each engine speed NE. Is calculated.

FIG. 3 is a flowchart showing a control procedure of the ignition timing of the control device according to the present invention.

First, the engine speed NE detected by the NE sensor 11 is changed to a predetermined speed (for example, 2100 rpm).
m) It is determined whether or not it is below, that is, whether or not the engine is in a low rotation speed state (step S1). If it is determined that the engine speed is equal to or lower than the predetermined rotation speed, that is, if the engine is in a low rotation state, the predetermined opening of the throttle valve corresponding to the engine rotation speed NE is determined using the above-described θTH-NE map (FIG. 2). The degree θwot ₁ is retrieved from the θwot curve (step S2).

Next, the valve opening θTH ₁ detected by the θTH sensor 4 is compared with the predetermined valve opening θwot _1, and θT
It is determined whether H> θwot ₁ holds (step S
3). If θTH> θwot ₁ holds, the detection of the PBA sensor is delayed because the engine suddenly changes from the low load state to the high load state, and the output value of the PBA sensor is determined to be a specific operation state different from the actual load state. Then, decrement of the count value Cwot of the preset counter is started (step S4), and it is determined whether or not the count value Cwot has become “0” (step S5). Until the count value Cwot becomes “0”, an IGMAP search in the PA region is performed using the atmospheric pressure value detected by the PA sensor 14 using the ignition timing map stored in the storage unit 5c (step S6), the ignition advance value θIG corresponding to the engine speed NE and the atmospheric pressure PA
a is read and stored in the RAM of the storage means 5c (step S
7) After that, the flag Twot is set to "1" (step S8), the desired ignition advance value θIG is set to θIGa (step S9), and the program ends.

On the other hand, at step S1, the engine speed NE
Is determined to be not equal to or greater than the predetermined rotational speed NEwot, it is determined that the rotational speed is not in the rotational region where knocking occurs due to a delay in pressure detection when accelerating from a low rotational speed region.
3, the valve opening θTH of the throttle valve 3 ′ is equal to the predetermined valve opening θwo.
If it is determined that t ₁ is smaller than, is determined not to be the case suddenly changed from a low load state to the high load state, after setting the count value Cwot to an initial value together (step S1
0), and sets the flag Twot to “0”.

Thereafter, an IGMAP search in the PBA region is performed by using the ignition timing map by using the detection value of the PBA sensor 8 (step S12).
The ignition advance value θIGba for A is read out and stored in the RAM (step S13). If the count value Cwot becomes “0” in step S5, the engine speed NE
Reaches the predetermined upper limit and the tracking delay of the PBA sensor 8 disappears.
A MAP search is performed (step S12), and the read ignition advance value θIGba is stored in the RAM (step S13).

Next, it is determined whether or not the flag Twot is "0" (step S14). If Fwot = 0, it is not in the specific operation state, but already in Step S11.
Since t = 0 is set, the desired ignition advance value θIG is set to θIGba (step S15),
Exit this program. On the other hand, the flag Twot is "0".
If not, it is a case where the count value Cwot becomes Cwot = 0 after a lapse of a predetermined period from the specific operation state, and a value obtained by adding a small value △ θIG to the ignition advance value θIGa stored in the RAM in step 7 Is set to a new ignition advance value θIGa (step S16). Next, it is determined whether or not the newly set ignition advance value θIGa is larger than the θIGba value stored in the RAM in step S13, that is, θIGa.
> ΘIGba is determined (step S1)
7). And when θIGa> θIGba holds,
The flag Twot is set to "0" (step S18), and the ignition advance value θIG is set to θIGba (step S1).
9) End this program. On the other hand, step S17
If θIGa> θIGba does not hold, then from θIGa to θ
In the transition to IGba, the ignition advance value θIG is set to θIGa calculated in step S16 (step S16).
9) End this program.

FIG. 4 is a diagram showing a change in the ignition advance value θIG when the engine operation state suddenly changes from a low load state to a high load state.

As shown in FIG. 4, when the valve opening .theta.TH of the throttle valve 3 'is greatly opened from a low engine rotation state and suddenly changes from a low load state to a high load state, PB
Since the detection value of the A sensor 8 has a delay in following the valve opening θTH, the ignition advance value θIGa is set based on the detection value of the PA sensor 14, and the ignition timing is controlled by the ignition advance value θIGa. At the same time, the decrement of the count value Cwot initially set to the count n is started. Then, after a predetermined period T has elapsed, the count value Cwot becomes 0, and the ignition advance value θIG based on the detection value of the PA sensor 14 is obtained.
From a, the ignition advance value θI based on the detection value of the PBA sensor 8
The ignition timing is controlled while gradually shifting to Gba in a stepwise manner. That is, as shown in FIG. 5, the ignition advance value θIG gradually increases the θIGa value by a small value ΔθIG over time, and finally shifts to the θIGba value.

That is, in the conventional example, the shift from the θIGa value to the θIGba value was immediately made as shown by the broken line, so that the engine torque greatly fluctuated and a shock was generated, which caused discomfort to the occupant. On the other hand, according to the present invention, the shift from the θIGa value to the θIGba value is gradually made stepwise after the predetermined period T has elapsed, so that the shock is suppressed and the discomfort to the occupant can be reduced.

In the above embodiment, the PA sensor 14
During the transition from a low load condition to a high load condition, PA
Although the ignition advance value θIGa was set based on the output value of the sensor 14, the PA sensor 14 was omitted, and PA = 760 mmH
θIGa may be calculated as g.

[0035]

As described in detail [devised effect above the present invention is the engine
An engine speed detecting means for detecting a speed,
Engine load detecting means for detecting the load state of the engine;
The engine speed detected by the engine speed detection means
And the engine speed detected by the engine load detecting means.
First point of setting ignition timing based on engine load condition
Fire timing setting means and the engine speed detecting means
Atmosphere detected by the detected engine speed and atmospheric pressure detection means
The ignition timing is set by the first ignition timing setting means based on the pressure.
Second setting of an ignition timing having characteristics different from the ignition timing
Ignition timing setting means, and a throttle valve of the engine.
A throttle valve opening detecting means for detecting an opening;
The engine speed is less than the predetermined engine speed and the slot
A predetermined throttle whose tor valve opening corresponds to the engine speed
Ignition timing setting by the first ignition timing setting means below the valve opening
The predetermined first region and the engine speed are determined by the predetermined engine.
Engine speed is less than or equal to
A second throttle valve opening not less than a predetermined throttle valve opening corresponding to the
A second region for setting the ignition timing by the ignition timing setting means;
The engine speed and the slot are determined in advance.
When the valve opening reaches the second range, the second ignition
Operate the engine at the ignition timing set by the timing setting means.
The engine speed or the throttle valve opening degree
When returning to the first region, immediately after the second ignition
The ignition timing set by the period setting means to the first point
Gradually shift to ignition timing set by fire timing setting means
Transfer control means for performing transfer control. Accordingly
The ignition time set by the second ignition timing setting means.
From the first ignition timing setting means
Large torque fluctuations even when shifting to the timing
Reduces shock to occupants and reduces driving performance
Can be improved.

[0036]

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of an ignition timing control device for an internal combustion engine according to the present invention.

FIG. 2 Reference valve opening corresponding to engine speed (NE)
It is a figure showing the value of (θwot).

FIG. 3 is a flowchart showing a control procedure of the present invention.

FIG. 4 is a diagram showing a variation state of the ignition advance value by the transition control means of the present invention.

FIG. 5 is an enlarged view of a main part (A part) of FIG. 4;

FIG. 6 is a diagram showing a conventional state of fluctuation of an ignition advance value.

[Explanation of symbols]

 8 Absolute pressure (PA) sensor (load detection means) 11 Engine speed NE sensor (speed detection means) 5b CPU (setting means, determination means, transition control means)

Claims (1)

(57) [Scope of request for utility model registration] An engine speed detecting means for detecting an engine speed, an engine load detecting means for detecting a load state of the engine, an engine speed detected by the engine speed detecting means and the engine load. First ignition timing setting means for setting the ignition timing based on the engine load state detected by the detection means; and an engine speed detected by the engine speed detection means.
The first ignition based on the atmospheric pressure by the atmospheric pressure detecting means;
Characteristics different from ignition timing set by timing setting means
Second ignition timing setting means for setting the ignition timing of
Throttle valve that detects opening of engine throttle valve
Opening degree detecting means, wherein the engine speed is a predetermined engine speed;
Engine speed is less than the engine speed
First ignition timing equal to or less than a predetermined throttle valve opening corresponding to
A first area for setting an ignition timing by a setting means and the engine;
Engine speed is less than the predetermined engine speed and the throttle
The throttle valve opening is determined by a predetermined slot corresponding to the engine speed.
Ignition by the second ignition timing setting means that is equal to or greater than the throttle valve opening
A second area for timing setting is determined in advance, and the engine
Engine speed and the throttle valve opening reach the second region.
Is immediately set by the second ignition timing setting means.
The engine is operated at the ignition timing
Is when the throttle valve opening returns to the first range
Is immediately set by the second ignition timing setting means.
The ignition timing is set by the first ignition timing setting means.
Transition control that performs transition control that gradually transitions to the ignition timing
Means for controlling the ignition timing of an internal combustion engine.