JP2001248530A - Ignition timing control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stable a combustion condition of an internal combustion engine without preventing rising a temperature of an exhaust gas emission control catalyst, in the case where a load amount an outside apparatus is changed when the temperature of the exhaust gas emission control catalyst is risen. SOLUTION: In this ignition timing control device for an internal combustion engine including a physical quantity in relation to a temperature of the exhaust gas emission control catalyst for purifying exhaust gas of the internal combustion engine and a load amount of an apparatus for applying a load on the internal combustion engine in a parameter for controlling the ignition timing of the internal combustion engine, control means (a step 1 to a step 8) for controlling the ignition timing of the internal combustion engine is disposed on the basis of a physical quantity in relation to the temperature of the exhaust gas emission control catalyst and a physical quantity in relation to an intake air amount corresponding to the sum of the load amounts of the apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling the ignition timing of an internal combustion engine, and more particularly, to a device for controlling a retard amount of the ignition timing.

[0002]

2. Description of the Related Art Conventionally, in an internal combustion engine, a basic ignition advance angle is determined based on a load of the internal combustion engine, for example, an intake pipe pressure or an intake air amount per rotation of the internal combustion engine, and a rotation speed of the internal combustion engine. Seeking. Then, based on the intake air temperature, the cooling water temperature, and the like, the basic ignition advance is corrected to obtain a correction value of the ignition advance, and the igniter is controlled using the correction value of the ignition advance as an ignition timing. Control is taking place.

[0003] On the other hand, an exhaust gas purifying catalyst (hereinafter simply referred to as a catalyst) is provided in the exhaust system of such an internal combustion engine. It is necessary to keep the temperature above the temperature at which the catalyst is activated.

[0004] However, when the internal combustion engine that has been stopped for a predetermined time is started, the purification rate of exhaust gas decreases until the temperature of the catalyst reaches the predetermined temperature.
Therefore, when starting the internal combustion engine that has been stopped for a predetermined time and is in a cold state, control for delaying the ignition timing has been proposed as a method for quickly raising the temperature of the catalyst. ing. When the ignition timing is retarded, the thermal efficiency of the internal combustion engine decreases, the temperature of the exhaust gas increases, and the temperature of the catalyst easily increases.

An example of an ignition timing control method for correcting the ignition timing retard amount in order to raise the temperature of the catalyst is described in Japanese Patent Application Laid-Open No. 62-91662. The ignition timing control device described in this publication is an air conditioner that uses the output of the internal combustion engine as a driving force source when retarding the basic ignition retard amount in accordance with the temperature decrease state of the internal combustion engine. Is operated, the retard amount of the ignition timing is reduced and corrected by an amount of a load corresponding to the operation of the air conditioner. By performing such control, the decrease in the output of the internal combustion engine due to the operation of the air conditioner is offset by the decrease correction, and the catalyst temperature can be rapidly increased even when the air conditioner is operating. Have been.

[0006]

However, in the above-mentioned publication, when the retardation amount of the ignition timing is corrected in accordance with the presence or absence of the operation of the air conditioner, the retardation amount of the ignition timing is fixed. The final retard amount is obtained by multiplying the values. For this reason, when the load of the air conditioner changes, for example, increases, the correspondence between the load and the retard amount of the ignition timing becomes inappropriate, and the combustion of the internal combustion engine may become unstable. There was sex. In particular, when starting the internal combustion engine,
The combustion is originally unstable due to insufficient warm-up. As a result, the combustion instability due to insufficient warm-up and the combustion instability due to improper control of the ignition timing retard amount overlap, and the combustion of the internal combustion engine becomes more unstable, and the idle speed is reduced. There was a possibility that the function became stable (the control function of the idle speed decreased).

[0007] The present invention has been made in view of the above circumstances, and when increasing the temperature of the exhaust gas purification catalyst, even if the load of an external device other than the exhaust gas purification catalyst changes, the temperature of the exhaust gas purification catalyst is increased. It is an object of the present invention to provide an ignition timing control device that can stabilize the combustion state of an internal combustion engine without hindering the combustion.

[0008]

In order to achieve the above object, the invention described in claim 1 purifies exhaust gas of an internal combustion engine to a parameter for controlling an ignition timing of the internal combustion engine. In an ignition timing control device for an internal combustion engine, which includes a physical quantity related to the temperature of the exhaust purification catalyst and a load quantity of a device that applies a load to the internal combustion engine,
Control means for controlling the ignition timing of the internal combustion engine based on a physical quantity related to the temperature of the exhaust gas purification catalyst and a physical quantity related to an intake air quantity corresponding to a total load of the device. It is characterized by the following. Here, examples of the device that applies a load to the internal combustion engine include a device that is driven by the internal combustion engine and an electric device that is operated by the power of a generator driven by the internal combustion engine.

According to the first aspect of the present invention, the parameters for controlling the ignition timing of the internal combustion engine include the physical quantity related to the temperature of the exhaust gas purification catalyst and the intake air quantity corresponding to the sum of the load of the equipment. Physical quantity to be included.
Therefore, the ignition timing is controlled with high accuracy in accordance with the degree of the load of the device that applies a load to the internal combustion engine, in addition to the temperature of the exhaust purification catalyst that applies a load to the internal combustion engine.

[0010]

Next, the present invention will be described in detail with reference to the accompanying drawings. FIG. 2 is a conceptual diagram showing the overall configuration of a vehicle to which the present invention is applied. As the internal combustion engine to which the present invention is applied, an engine, for example, a gasoline engine, a diesel engine, an LPG engine, or the like can be used. Hereinafter, this embodiment will be described based on the case where a gasoline engine is used as an engine for convenience. That is, to explain the schematic configuration of the engine 1, the ignition plug 4 </ b> A is disposed in the combustion chamber 3 formed on the top side of the piston 2. The combustion chamber 3 is connected to an intake port 5 having an intake valve 4 and an exhaust port 7A having an exhaust valve 6.

An intake pipe 8 communicates with the intake port 5, and a surge tank 9 is provided in the intake pipe 8. A fuel injection valve 10 is mounted between the intake port 5 and the surge tank 9 in the intake pipe 8. The surge tank 9 is connected to an air cleaner 11 via an intake pipe 8, and a throttle valve 12 is provided between the air cleaner 11 and the surge tank 9 in the intake pipe 8.

The throttle valve 12 in the intake pipe 8
A bypass passage 13 is provided to connect the upstream side in the intake direction with respect to the intake valve 8 and the downstream side in the intake direction with respect to the throttle valve 12 in the intake pipe 8, and an idle speed control valve 14 is disposed in the bypass passage 13. Have been. The exhaust pipe 7 is provided with a catalytic converter 15 containing a three-way catalyst (not shown).

On the other hand, an engine electronic control unit (ECU) 16 for controlling the engine 1 is constituted by a microcomputer mainly comprising an arithmetic processing unit (CPU or MPU), a storage unit (ROM and RAM), and an input / output interface. ing. The engine electronic control device 16 includes a signal of an ignition switch 50, a signal of an intake air temperature sensor 17, a signal of an intake air amount sensor 18, a signal of an intake air pressure sensor 19, a signal of a coolant temperature sensor 20, a throttle position sensor 21 , A signal from the crank position sensor 22, a signal from the catalyst temperature sensor 23, a signal from the air conditioner load sensor 24, a signal from the load sensor 25, a signal from the accelerator opening sensor 26, and a shift device (not shown) for controlling the transmission 33. The signal of the shift position sensor 37 for detecting the shift position of (3) is input.

The air conditioner load sensor 24 controls the air conditioner compressor 27 driven by the engine 1. The load sensor 25 is driven by the engine 1 and has a compressor 27 for an air conditioner.
This is for detecting the state of other devices (that is, auxiliary devices). Examples of this device include a device directly driven by the power of the engine 1, such as an alternator 28, an oil pump 29 for power steering, and an oil pump 33A that generates a source pressure of a hydraulic circuit for a transmission 33. Can be

The above-mentioned devices include a device that consumes electric power generated by an alternator 28 driven by the engine 1, for example, a battery 30 that stores electric power generated by the alternator 28, and a lighting device 31 that consumes the electric power. And a defogger 32. Then, based on the signal of the catalyst temperature sensor 23, the signal of the air conditioner load sensor 24, the signal of the load sensor 25, the signal of the shift position sensor 37, and the like, the output of the engine 1 consumed by various devices, that is, the load is obtained. .

In the electronic control unit 16 for the engine, predetermined arithmetic processing is performed based on data stored in advance and signals from the various sensors and switches, and various control signals corresponding to the processing results are performed. Is output from the engine electronic control unit 16. Various control signals include the igniter 2 connected to the ignition plug 4A.
7A, a signal for controlling the fuel injection valve 10, a signal for controlling the idle speed control valve 14, and an actuator 28 for the throttle valve 12.
And a signal for controlling.

A power transmission device, for example, a transmission 33 and a differential device 34 is provided on the output side of the engine 1, and the torque of the engine 1 is transmitted to the wheels 35 via the transmission 33 and the differential device 34. Is transmitted to Further, the brake booster 36 constituting a part of the braking device is configured to operate a diaphragm (not shown) based on a pressure difference between a negative pressure generated in the intake pipe 8 and the atmospheric pressure.
Further, the power steering oil pump 38 is driven by the power of the engine 1.

Here, the correspondence between the configuration of this embodiment and the configuration of the present invention will be described. The engine cited example corresponds to the internal combustion engine of the present invention, and the catalytic converter 15 corresponds to the exhaust purification catalyst of the present invention. And air conditioner compressor 2
7, the alternator 28, the oil pumps 29 and 33A, the battery 30, the lighting device 31, and the defogger 32 correspond to the device of the present invention.

In the above configuration, when the engine 1 is operated, the exhaust gas flows through the exhaust pipe 7 and is purified by the exhaust purification catalyst. Here, in order to increase the purification rate of the exhaust gas by the catalytic converter 15, it is necessary to maintain the temperature of the catalyst at or above a predetermined temperature at which the catalyst is activated. However, when the engine 1 that has been stopped for a predetermined time is started, the exhaust gas purification rate decreases until the temperature of the catalyst reaches the predetermined temperature.

Therefore, the operation is stopped for a predetermined time,
And when starting the engine 1 in a cold state,
A control example in the case where the ignition timing is retarded in order to quickly raise the temperature of the catalyst will be described with reference to the flowchart shown in FIG. When the ignition timing calculation routine shown in FIG. 1 is started, first, an air conditioner load correction amount qac calculated based on a signal from the air conditioner load sensor 24 and various auxiliary machines calculated based on a signal from the load sensor 25. The electric load correction amount qels is taken in as data.

Here, the air conditioner load correction amount means a correction amount of an air amount by ISC (idle speed control) corresponding to an engine output consumed for driving the air conditioner compressor 27. Also, the electric load correction amount is
The engine output consumed by the operation of the lighting device 31 and the defogger 32 is converted into electric energy, and the amount of correction of the air amount by ISC obtained from the converted value is meant. The air conditioner load correction amount and the electric load correction amount are calculated by an ISC control routine.

The idle speed control will be briefly described. Idle speed control
When the throttle valve 12 is in the fully closed state, the idling speed of the engine 1 is controlled to be as constant as possible, while the rotation is less likely to be unstable, and vibration and engine stall can be suppressed. The control is performed to control the engine 1 such that First, a target idle speed is calculated based on conditions such as a cooling water temperature, a load correction amount, and an electric load correction amount. Then, the opening of the idle speed control valve 14 is controlled so that the actual engine speed approaches the target idle speed, and the passage area of the intake air is continuously changed.

In step S1, it is determined whether the engine 1 is cold and after the engine 1 is started, based on the signal from the cooling water temperature sensor 20 and the signal from the ignition switch 50. (Step S
2). If a positive determination is made in step S2,
The engine water temperature ethw and the engine load factor (specifically, data indicating the charging efficiency of the engine 1 (the efficiency related to gas exchange of the engine 1, the scavenging efficiency, the supply efficiency, and the efficiency obtained from the supply ratio)) Is calculated based on the map showing the relationship (step S3).

An example of the characteristics of the map used in step S3 is that when the engine water temperature is in a range from a predetermined low temperature to a predetermined high temperature and the engine load factor is equal to or lower than a predetermined value, the engine water temperature increases. To reduce the basic retard amount in accordance with the above, or when the engine water temperature is in a range from a predetermined low temperature to a predetermined high temperature, and the engine load factor is equal to or less than a predetermined value,
In addition to reducing the basic retard amount with the rise of the engine water temperature, the basic retard amount may be reduced from a point in time when the temperature exceeds a predetermined temperature.

After step S3, the air-conditioner load correction amount and the electric load correction amount calculated in step S1 are added to calculate an intake air increase amount Δq corresponding to idle speed control control (step S3).
4). Then, the ignition timing correction amount eqacatd for the basic retard amount is calculated based on the intake air increase amount (step S5). In step S5, a map is used in which the intake air increase amount (l / sec) and the ignition timing correction amount (degree) correspond to each other. In the map used in step S5, the ignition timing correction amount is set to increase as the intake air increase amount increases.

Further, the step S
A value indicating how much the ignition timing correction amount calculated in step 5 is reflected, that is, a reflection rate k2 is calculated (step S6). In step S6, the engine water temperature and the integrated air amount egal per displacement amount of the engine 1 are determined.
A map showing the relationship with sum is used. The map used in FIG. 6 is set so that, for example, regardless of the engine water temperature, the reflection rate increases as the integrated air amount increases.

Then, the corrected retard amount Re is calculated by adding the basic retard amount calculated in step S3 and the ignition timing correction amount calculated in step S5 (step S7). In step S7, a guard process is performed so that the post-correction retard amount does not reversely correct the ignition timing. This guard processing is
Even if the calculation result of the post-correction retard angle is a value that advances the ignition timing for some reason, the advanced retard control of the ignition timing is prevented from occurring by setting the correction retard amount to “zero”. Means the processing to be performed.

Thereafter, the calculated retardation amount CRe is calculated by multiplying the corrected retardation amount by the reflection rate (step S).
8), the control routine ends. Step S
If a negative determination is made in 2, the control routine is terminated.

As described above, in this embodiment,
When starting the engine 1 in the cold state and retarding the ignition timing in order to maintain the catalyst temperature of the catalytic converter 15 at a predetermined value, it corresponds to the total load of equipment that applies a load to the engine 1. The basic value of the ignition timing is corrected based on the amount of intake air to be obtained, and its final value (ie, the calculated amount of retardation) is obtained. In other words, when the retard control by another load is determined to have the same effect as the retard control of the ignition timing necessary to control the catalyst temperature to the predetermined temperature, or the retard control by the other load occurs. Accordingly, when the warm-up property necessary for controlling the catalyst temperature to the predetermined temperature is sufficiently ensured, the extra retard amount is reduced. Therefore, when starting the engine 1 in the cold state, the catalytic converter 15 is sufficiently warmed up and its purification performance can be improved, while the combustion state of the engine 1 can be stabilized, and Vibration of the engine 1 and engine stall at the time of starting the vehicle can be suppressed.

Further, since the combustion state of the engine 1 is stabilized and the correction amount of the intake air amount for maintaining the idle speed decreases, the negative pressure in the intake pipe 8 also increases. Therefore, it is possible to prevent the operation of the device using the negative pressure of the intake pipe 8 as a power source, for example, the function of the brake booster 36 from being hindered.

Further, in step S4, when calculating the intake air increase amount, the air conditioner compressor 27
And a predetermined load other than the electrical load. For example, the driving load of the oil pump 38 calculated at the time of idle speed control can be applied as the predetermined load. Further, an automatic transmission capable of automatically controlling the gear ratio is mounted as the transmission 33. By operating the shift device, a non-driving position, for example, N (neutral) position is changed to a driving position, for example, D. It may be possible to switch to the (drive) position. In this case, when the operation is switched from the N position to the D position, the engine load accompanying the driving of the oil pump 33A increases in order to increase the engagement pressure of the friction engagement device. Therefore, an increase in engine output corresponding to such a shift position switching operation can be applied in advance as a predetermined load.

Further, in step S5, when calculating the ignition timing retard correction amount from the intake air increase amount corresponding to the total load, a calculation formula is stored in the engine electronic control unit 16 in advance, and this calculation is performed. A control logic for calculating the ignition timing retard correction amount based on the equation may be employed. That is, when the above-described map is used in the calculation processing in step S5, the engine electronic control unit 1
6, the number of words of the data stored in the storage device increases. However, if the ignition timing retard correction amount is calculated by a calculation formula, the data to be stored in the engine electronic control device 16 in advance is calculated. There is an advantage that the number of words can be reduced. Here, the correspondence between the functional means shown in FIG. 1 and the configuration of the present invention will be described.
The control performed in steps S8 to S8 corresponds to the control means of the present invention.

The following is a description of the characteristic configuration of the present invention disclosed on the basis of the above specific examples. That is, the parameters for controlling the ignition timing of the internal combustion engine include a physical quantity related to the temperature of the exhaust purification catalyst that purifies the exhaust gas of the internal combustion engine and a load quantity of a device that applies a load to the internal combustion engine. In the ignition timing control device for an internal combustion engine, a basic retardation amount calculating means for calculating a basic retardation amount based on a physical quantity related to a temperature of the exhaust gas purification catalyst, and an intake corresponding to a total load amount of the device A correction value calculation unit that calculates a correction value based on a physical quantity related to an air amount, and a final retardation amount calculation unit that corrects the basic retardation amount based on the correction value. Timing control device for an internal combustion engine. Explaining the correspondence between this configuration and the functional means of FIG. 1, step S3 corresponds to the basic retard amount calculating means, steps S4 and S5 correspond to the correction value calculating means, and steps S6, S7 and S8. Corresponds to the final retard amount calculation means.

[0034]

As described above, according to the first aspect of the present invention, the physical quantity related to the temperature of the exhaust gas purifying catalyst is:
The ignition timing is controlled with a high degree of accuracy in accordance with the total load of the devices that apply a load to the internal combustion engine. Therefore, the combustion state can be stabilized, and the vibration of the internal combustion engine,
Further, it is possible to suppress the stop of the internal combustion engine when the vehicle starts.

[Brief description of the drawings]

FIG. 1 is a flowchart showing one control example of the present invention.

FIG. 2 is a conceptual diagram showing an overall configuration of a vehicle to which the present invention is applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine, 15 ... Catalytic converter, 27 ... Air conditioner compressor, 28 ... Alternator, 29,3
3A: oil pump, 30: battery, 31: lighting device, 32: defogger.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Kiyoo Hirose 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Kenichiro Sato 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F Terms (Reference) 3G022 CA02 CA03 DA02 EA07 EA08 GA06 GA07 GA08 GA09 GA10 GA11 GA17 GA20 3G091 AA02 AA17 AA18 AA19 AA23 AB03 BA03 BA14 BA15 BA19 BA32 CB02 CB05 CB07 CB08 CB09 DA01 DA02 DB06 DB10 EA01 EA03 EA03 EA03 EA03 EA03 EA03 EA03 EA40 FA02 FA04 FA12 FA13 FB02 FB11 FC07 HA39

Claims (1)

[Claims] A parameter for controlling an ignition timing of an internal combustion engine includes a physical quantity related to a temperature of an exhaust purification catalyst for purifying exhaust gas of the internal combustion engine, and a load quantity of a device that applies a load to the internal combustion engine. In the ignition timing control device for an internal combustion engine, based on a physical quantity related to a temperature of the exhaust gas purification catalyst and a physical quantity related to an intake air quantity corresponding to a total load of the equipment, An ignition timing control device for an internal combustion engine, comprising control means for controlling the ignition timing of the engine.