JP2007056784A - Ignition time controller for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition time controller for an internal combustion engine capable of obtaining ignition time for eliminating knocking quickly and pulling out output torque of the engine sufficiently in the control for retarding ignition time of an ignition plug when knocking of the engine occurs. <P>SOLUTION: When current amount of retard angle compensation of ignition time of the ignition plug 2 is small, amount of retard angle (retard angle control latitude) in the retard angle control is increased to bring ignition time after compensation close to the optimum ignition time quickly. When current amount of retard angle compensation of ignition time of the ignition plug 2 is large, amount of retard angle (retard angle control latitude) in the retaed angle control is reduced to avoid such situation that the ignition time after compensation is deviated onto a retard angle side from the optimum ignition time greatly. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ignition timing control device for an internal combustion engine represented by an automobile engine or the like. In particular, the present invention relates to improved control for retarding the ignition timing of an ignition plug (ignition plug) when knocking occurs in an internal combustion engine.

  In an engine (internal combustion engine) mounted on a vehicle such as an automobile, the ignition timing of the engine greatly affects exhaust gas, fuel consumption, drivability (engine output torque), etc. The ignition timing is controlled so that the optimum timing is obtained. In this ignition timing control, for example, an ECU (electronic control unit) calculates an optimal ignition timing based on the operating state of the engine (for example, engine speed and load), and the calculated ignition timing is applied to the spark plug. Is igniting.

  Further, in an engine mounted on a vehicle, ignition timing control is performed by a KCS (knock control system) that suppresses the occurrence of knocking. In the ignition timing control by KCS, for example, as disclosed in Patent Document 1 below, the presence or absence of knocking is determined based on the output signal of the knock sensor, and the ignition timing is determined based on the determination result as the basic ignition timing. The ignition timing is retarded (ignition timing determined according to engine speed and load). As a result, the combustion speed of the air-fuel mixture is reduced, the maximum combustion pressure is kept low, and the occurrence of knocking is suppressed. When it is determined that knocking has not occurred, ignition timing control is performed in which the ignition timing is gradually advanced to optimize the ignition timing.

Further, as a technique related to ignition timing control by KCS as described above, Patent Document 2 below recognizes in advance cylinders that are likely to cause knocking and cylinders that are unlikely to cause knocking, and performs control delay independently for each cylinder. It is disclosed that an upper limit value and a lower limit value of the angular amount are set, and thereby, ignition timing control is performed for each cylinder within an individual limit range to prevent an excessive retard angle or an excessive advance angle. On the other hand, Patent Document 3 below discloses changing the relative ratio of the retard amount and the advance amount in the knocking control in accordance with the knocking occurrence frequency for each cylinder. That is, when the occurrence frequency of knocking increases, the retardation ratio of the cylinder is increased, while when the occurrence frequency of knocking decreases, the advancement ratio of the cylinder is increased.
Japanese Patent No. 2629204 JP 63-179176 A Japanese Patent Laid-Open No. 2-185673

  However, in general ignition timing retardation control for occurrence of knocking so far, the retardation control is performed at constant angular intervals in the same cylinder, although the retardation correction amount is different for each cylinder. It was. For example, when the retard control width is set to 10 °, every time knocking occurs, the ignition timing is retarded by 10 ° from the current ignition timing. There is a possibility that the ignition timing will be retarded significantly. For example, even in a situation where the optimal ignition timing is delayed by 2 ° from the current ignition timing, when knocking occurs, the ignition timing is retarded by 10 °, which is 8 ° more than the optimal ignition timing. Plug ignition is performed at a retarded position. This makes it impossible to sufficiently extract the engine output torque.

Further, Patent Document 3 discloses that as a control for changing the retardation ratio, if the occurrence frequency of knocking increases, the retardation ratio of the cylinder is increased. However, this ignition timing retardation control is disclosed. However, if knocking occurs with a high frequency of knocking, the ignition timing will be greatly retarded, and the ignition timing will be retarded significantly from the optimal ignition timing, resulting in engine output torque. May lead to a situation where it is not possible to withdraw sufficiently.

  In order to solve the above problems, it is possible to set a small control width of the ignition timing that is retarded each time knocking occurs. For example, the retard control width is fixed to 1 °. However, in this case, there is a possibility that knocking cannot be resolved over a long period of time because the retardation amount of the retardation control that is executed each time knocking occurs is too small.

  The present invention has been made in view of such a point, and an object of the present invention is to quickly eliminate knocking with respect to control for retarding the ignition timing of a spark plug when engine knocking occurs, and It is an object of the present invention to provide an ignition timing control device for an internal combustion engine capable of obtaining an ignition timing capable of sufficiently extracting output torque.

-Principle of solving the problem-
The solution principle of the present invention taken to achieve the above object recognizes the current retard correction amount (correction amount to the retard side with respect to the basic ignition timing), and this present retard correction amount is small. It is determined that the corrected ignition timing is far from the optimal ignition timing, and conversely, it is determined that the corrected ignition timing approaches the optimal ignition timing as the current retard correction amount increases. When the current retard correction amount is small, the retard amount (retard control width) of the retard control is increased so that the corrected ignition timing is brought close to the optimum ignition timing quickly, and the current retard angle is increased. By reducing the retard amount (retard control width) of the retard control when the correction amount is large, avoiding the situation where the corrected ignition timing is significantly shifted from the optimum ignition timing. Like to do.

-Solution-
Specifically, the present invention is premised on an ignition timing control device for an internal combustion engine that performs ignition delay control that retards the ignition timing of the spark plug when knocking occurs in the internal combustion engine. With respect to this ignition timing control device, a current retard correction amount recognizing means for recognizing the current retard correction amount of the ignition timing, a knocking detecting means for detecting that knocking has occurred in the internal combustion engine, and the current retard angle And an addition delay correction amount calculating means for receiving an output of the correction amount recognition means and the knock detection means and calculating an addition delay correction amount to be added to the current delay angle correction amount when knocking occurs. Then, according to the magnitude of the current retardation correction amount (for example, the ratio of the current retardation correction amount to the predetermined retardation allowable amount (maximum retardation amount)), The calculated addition retardation correction amount is changed.

  More specifically, the addition retardation correction amount calculating means calculates the addition retardation correction amount as a smaller value as the current retardation correction amount is larger.

With this specific matter, when the knocking detection means detects the occurrence of knocking during the operation of the internal combustion engine, the ignition timing is retarded (retarded with respect to the basic ignition timing) so as to suppress the occurrence of knocking. The current retardation correction amount recognition means recognizes the current retardation correction amount. The retardation correction amount in this ignition timing retardation control is calculated by the additional retardation correction amount calculation means. That is, the additional retardation correction amount calculating means changes the calculated additional retardation correction amount in accordance with the current retardation correction amount. Specifically, the added retardation correction amount is calculated as a smaller value as the current retardation correction amount is larger. For this reason, when the current retard correction amount is small, the retard amount (retard control width) of the retard control is increased, and even if the current ignition timing is far from the optimal ignition timing, the retard is delayed. The ignition timing after the angle correction can be quickly brought close to the optimum ignition timing. on the other hand,
When the current retard correction amount is large, the retard amount (retard control width) of the retard control is reduced, and the ignition timing after the retard correction is significantly shifted to the retard side from the optimum ignition timing. It is possible to avoid such a situation. As a result, the convergence of the ignition timing to the optimal ignition timing can be improved, knocking can be quickly eliminated, and the output torque of the engine can be sufficiently extracted.

  Specific configurations for calculating the addition retardation correction amount include the following. That is, the internal combustion engine is a multi-cylinder internal combustion engine having a plurality of cylinders, and the added retard angle correction amount calculation means has a magnitude of the current retard angle correction amount with respect to the cylinder specific correction value preset for each cylinder. The addition delay angle correction amount is calculated by multiplying the variable set in accordance with. The cylinder specific correction value here is a value set in advance according to the ease of occurrence of knocking in each cylinder. For example, because the ease of knocking varies depending on the compression ratio of each cylinder and variations in heat dissipation, etc., the correction value to the retard side (cylinder-specific correction value) is set larger for cylinders that are more likely to knock. ing. With this specific matter, the convergence of the ignition timing to the optimum ignition timing in each cylinder can be further improved, and knocking can be quickly eliminated and the engine output torque can be reliably improved.

  Moreover, the following is mentioned as a structure for calculating | requiring the final ignition timing of a spark plug using the said addition delay amount correction amount calculated | required. That is, with respect to the reference ignition timing determined in accordance with the operating state of the internal combustion engine, the added retard correction amount calculated by the added retard correction amount calculating means and the current retard recognized by the current retard correction amount recognizing means. The final ignition timing is obtained by adding the angle correction amount to the retard side. The reference ignition timing here is a value determined by the rotational speed, load, etc. of the internal combustion engine. In this way, by adding the retard correction amount calculated according to the current retard correction amount to the retard side with respect to the reference ignition timing, in the multi-cylinder internal combustion engine, an optimum final value for each cylinder. The ignition timing can be obtained, knocking can be quickly eliminated, and the output torque of the engine can be sufficiently extracted.

  In the present invention, the current retard correction amount is recognized with respect to the control for retarding the ignition timing of the spark plug when knocking of the internal combustion engine occurs, and the retard control is delayed according to the present retard correction amount. The angular amount (addition retardation correction amount) is changed. More specifically, when the current retard correction amount is small, the added retard correction amount of the retard control is increased so that the corrected ignition timing is quickly brought close to the optimum ignition timing, and the current retard is corrected. The larger the angle correction amount is, the smaller the added retard angle correction amount of the retard angle control is made, so that the situation where the corrected ignition timing is significantly shifted from the optimal ignition timing to the retard side is avoided. . For this reason, it is possible to obtain an ignition timing that can quickly eliminate knocking of the internal combustion engine and sufficiently extract the output torque of the engine.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a case where the present invention is applied to a multi-cylinder (for example, four-cylinder) gasoline engine mounted on an automobile will be described.

-Outline configuration of engine-
FIG. 1 shows a schematic configuration of an engine (internal combustion engine) 1 according to the present embodiment. FIG. 1 shows only the configuration of one cylinder of the engine 1.

As shown in FIG. 1, the engine 1 includes a piston 10 that forms a combustion chamber 1a and a crankshaft 13 that is an output shaft. The piston 10 is connected to the crankshaft 13 via a connecting rod 14, and the reciprocating motion of the piston 10 is converted into rotation of the crankshaft 13 by the connecting rod 14.

  A signal rotor 15 having a plurality of protrusions 15a, 15a,... Is attached to the crankshaft 13 on the outer peripheral surface. A crank position sensor 26 is disposed near the side of the signal rotor 15. The crank position sensor 26 outputs a pulse signal corresponding to the protrusion 15a of the signal rotor 15 when the crankshaft 13 rotates.

  An ignition plug (ignition plug) 2 is disposed in the combustion chamber 1 a of the engine 1. An ignition coil 3 and an igniter 4 are connected to the spark plug 2. The igniter 4 drives the ignition coil 3 in accordance with an ignition signal from the ECU 30 described later to ignite the spark plug 2. The ignition timing control of the spark plug 2 will be described later.

  Further, the engine 1 is provided with a water temperature sensor 21 and a knock sensor 27 that detect the engine water temperature (cooling water temperature). The knock sensor 27 is a vibration type sensor that detects vibration of the engine transmitted to the cylinder block 1b of the engine 1 by a piezoelectric element type (piezo element type) or an electromagnetic type (magnet, coil).

  An intake passage 101 and an exhaust passage 102 are connected to the combustion chamber 1 a of the engine 1. An intake valve 11 is provided between the intake passage 101 and the combustion chamber 1a. By opening and closing the intake valve 11, the intake passage 101 and the combustion chamber 1a are communicated or blocked. An exhaust valve 12 is provided between the exhaust passage 102 and the combustion chamber 1a, and the exhaust passage 102 and the combustion chamber 1a are communicated or blocked by opening and closing the exhaust valve 12. The opening / closing drive of the intake valve 11 and the exhaust valve 12 is performed by each rotation of the intake camshaft and the exhaust camshaft to which the rotation of the crankshaft 13 is transmitted.

An air cleaner 8, a hot-wire air flow meter 22, an intake air temperature sensor 23 (built in the air flow meter 22), and an electronically controlled throttle valve 5 for adjusting the intake air amount of the engine 1 are arranged in the intake passage 101. Has been. The throttle valve 5 is driven by a throttle motor 6. The opening degree of the throttle valve 5 is detected by a throttle position sensor 25. In the exhaust passage 102 of the engine 1, an O ₂ sensor 24 for detecting the oxygen concentration in the exhaust gas and a catalyst (for example, a three-way catalyst) 9 are arranged.

  A fuel injection injector (fuel injection valve) 7 is disposed in the intake passage 101. The injector 7 is supplied with fuel of a predetermined pressure from a fuel tank by a fuel pump, and the fuel is injected into the intake passage 101. This injected fuel is mixed with intake air to form an air-fuel mixture and introduced into the combustion chamber 1a of the engine 1. The air-fuel mixture (fuel + air) introduced into the combustion chamber 1a is ignited by the spark plug 2 and burned. The piston 10 reciprocates by the combustion of the air-fuel mixture in the combustion chamber 1a, and the crankshaft 13 rotates.

-Description of control block-
The operating state of the engine 1 is controlled by an ECU (electronic control unit) 30. As shown in FIG. 2, the ECU 30 includes a CPU 31, a ROM 32, a RAM 33, a backup RAM 34, and the like.

  The ROM 32 stores various control programs, maps that are referred to when the various control programs are executed, and the like. The CPU 31 executes arithmetic processing based on various control programs and maps stored in the ROM 32.

  The RAM 33 is a memory for temporarily storing calculation results in the CPU 31 and data input from each sensor. The backup RAM 34 is a non-volatile memory for storing data to be saved when the engine 1 is stopped. is there. The ROM 32, CPU 31, RAM 33 and backup RAM 34 are connected to each other via a bus 37 and are also connected to an external input circuit 35 and an external output circuit 36.

The external input circuit 35 includes the water temperature sensor 21, air flow meter 22, intake air temperature sensor 23, O ₂ sensor 24, throttle position sensor 25, crank position sensor 26.
And the knock sensor 27 is connected. On the other hand, the injector 7, the igniter 4, the throttle motor 6 of the throttle valve 5, and the like are connected to the external output circuit 36.

Then, the ECU 30 determines the igniter 4 based on the output signals of various sensors such as the water temperature sensor 21, the air flow meter 22, the intake air temperature sensor 23, the O ₂ sensor 24, the throttle position sensor 25, the crank position sensor 26, and the knock sensor 27. By controlling each part such as the injector 7 and the throttle motor 6, various controls of the engine 1 including the following ignition timing control (retarding angle control) are executed.

-Ignition timing retard control-
Next, the ignition timing retardation control operation of the spark plug 2 at the time of occurrence of knocking, which is a control operation characteristic of the present embodiment, will be described. The processing operation of the ECU 30 related to this ignition timing retardation control operation includes a recognition operation of the current retardation correction amount of the ignition timing (operation by the current retardation correction amount recognition means), and that the engine 1 has been knocked. (The operation by the knocking detection means), and the operation for calculating the additional retardation correction amount to be added to the current retardation correction amount when knocking occurs (the operation by the addition retardation correction amount calculation means). As an operation for calculating the additional retardation correction amount by the additional retardation correction amount calculating means, the larger the current retardation correction amount is, the more specifically, the current retardation with respect to the maximum retardation amount (AKMAX) described later. As the ratio of the correction amount (AKNK) is larger, the addition retardation correction amount (αAKNK) is calculated as a smaller value. Detailed control operation will be described later.

  Next, the procedure of the ignition timing retardation control operation of the spark plug 2 when knocking occurs will be described with reference to the flowchart of FIG. As a basic operation of the ignition timing retarding control operation, the ECU 30 monitors the occurrence of knocking of the engine 1 based on the detection result of the knock sensor 27, and retards the ignition timing when knocking occurs. Suppress knocking. On the other hand, when knocking does not occur, the ignition timing is advanced to increase the engine output. The detection of the occurrence of knocking is performed, for example, by determining whether or not the peak value of the output signal of the knock sensor 27 is equal to or higher than the knock determination level.

  The ignition timing retarding control operation described below with reference to the flowchart is executed for each cylinder individually. However, since the occurrence timing of knocking is often during the expansion stroke of each cylinder, the expansion is performed for each cylinder. This ignition timing control operation is performed when knocking occurs in the cylinder when the stroke is started. Hereinafter, the procedure of the ignition timing retarding control operation for a cylinder when knocking occurs in the cylinder will be described.

  First, in step ST1, the engine speed (Ne) is calculated based on the pulse signal from the crank position sensor 26. In step ST2, the engine load factor ((KL) is calculated. This load factor (KL) is a value indicating the current load ratio with respect to the maximum engine load of the engine 1, and is detected by the air flow meter 22, for example. It is calculated with reference to a load factor map based on the intake air amount and the engine speed (Ne).

In step ST3, the basic ignition timing (abse) is calculated. This basic ignition timing (a
bse) is calculated with reference to a basic ignition timing map that determines the ignition timing based on the engine speed (Ne) and the engine load factor (KL). In other words, this basic ignition timing (abse) is determined regardless of the conditions such as whether or not the target cylinder is more likely to knock than the other cylinders, the ignition timing retardation correction amount at the present time, and the like. Is. Specifically, the basic ignition timing (abse) is set to the retard side as the engine speed (Ne) is higher and as the engine load factor (KL) is higher.

  Thereafter, in step ST4, a cylinder-by-cylinder correction base value (cylinder-by-cylinder correction value in the present invention: earcyl) is read. The cylinder-specific corrected base value (earcyl) is a value set in advance according to the ease of occurrence of knocking in each cylinder. For example, since the ease of occurrence of knocking varies depending on the compression ratio of each cylinder, variation in heat dissipation, etc., the cylinder-specific correction base value (earcyl), which is the correction value to the retard side, is more likely to occur in the cylinder where knocking is likely to occur. Is set larger. Specifically, in cylinders where deposits tend to accumulate in the cylinders and in the two cylinders in the center of the in-line four-cylinder engine, this cylinder-specific corrected base value (earcyl) is set higher than the other cylinders. The cylinder-specific corrected base value (earcyl) is also changed according to the position where the knock sensor 27 is disposed. For example, the cylinder-specific correction base value (earcyl) is set higher for cylinders located farther away from the position where the knock sensor 27 is disposed. The cylinder-specific corrected base value (earcyl) is stored in advance in the ROM 32 for each cylinder.

  Thereafter, the process proceeds to step ST5, and the maximum retardation amount (AKMAX) is calculated. The maximum retard amount (AKMAX) is the maximum retard amount of the ignition timing that is allowable at the current engine speed (Ne) and engine load factor (KL), and the engine speed (Ne) and engine load factor. The maximum retardation amount calculation map based on (KL) is referred to and calculated. Specifically, the maximum retard amount (AKMAX) is set to be larger as the engine speed (Ne) is higher and as the engine load factor (KL) is higher.

  In step ST6, an ignition timing retardation correction amount (current retardation angle correction amount: AKNK obtained by the previous ignition timing retardation control operation) is calculated based on the ignition timing control operation currently performed. Calculated. This is calculated | required by reading the control command value of the ignition timing control operation currently performed by ECU30 with respect to the object cylinder.

  In step ST7, an operation for calculating an additional retardation correction amount (αAKNK) is performed. This additional retard correction amount (αAKNK) further corrects the ignition timing to the retard side with respect to the ignition timing corrected from the basic ignition timing (abse) to the retard side by the current retard correction amount (AKNK). Therefore, it becomes a retarded addition value. Specifically, the operation of calculating the added retardation correction amount (αAKNK) is executed by the following arithmetic expression (1).

Addition retardation correction amount (αAKNK) = {1− (AKNK / AKMAX)} × earcyl
... (1)
From this calculation formula, the larger the ratio of the current retardation correction amount (AKNK) to the maximum retardation amount (AKMAX), the smaller the added retardation correction amount (αAKNK) is calculated. That is, when the current retardation correction amount (AKNK) is small (the ratio to the maximum retardation amount is small), the retardation control width (additional retardation correction amount) of the retardation control is increased, and conversely the current retardation angle. When the correction amount (AKNK) is large (the ratio to the maximum retardation amount is large), the retardation control width (addition retardation compensation amount) of the retardation control is made small. In other words, when the current retard correction amount (AKNK) is small, the added retard correction amount (αAKNK) is increased so that the corrected ignition timing is quickly brought close to the optimal ignition timing, while the current retard angle is increased. When the correction amount (AKNK) is large, the addition delay angle correction amount (αAKNK) is decreased to avoid a situation in which the corrected ignition timing is significantly shifted from the optimal ignition timing to the retard side. , The above added retardation correction amount (αAKN
K) is calculated.

  In step ST8, the final ignition timing (aop) is calculated using the added retardation correction amount (αAKNK) obtained in step ST7. This final ignition timing (aop) calculation operation is executed by the following arithmetic expression (2).

Final ignition timing (aop) = abse−αAKNK−AKNK (2)
In this arithmetic expression, the − (minus) side is represented as the retard side.

  A command signal of the final ignition timing (aop) calculated by the above operation is output from the ECU 30 to the igniter 4, and the spark plug 2 is ignited according to this command signal.

  As described above, in the present embodiment, when the current retard correction amount (AKNK) is small, the retard amount (retard control width) of the retard control is increased, and the current retard correction amount ( Even if AKNK) is far from the optimum ignition timing, the ignition timing after the retardation correction can be quickly brought close to the optimum ignition timing. On the other hand, when the current retard correction amount (AKNK) is large, the retard amount (retard control width) of the retard control is reduced, and the ignition timing after the retard correction is significantly delayed from the optimum ignition timing. It is possible to avoid a situation where the corner is shifted. As a result, the convergence of the ignition timing to the optimal ignition timing can be improved, knocking can be quickly eliminated, and the output torque of the engine can be sufficiently extracted.

  Further, in the conventional general ignition timing retardation control, only the correction by the cylinder-specific correction base value (earcyl) is performed on the basic ignition timing (abse). The cylinder-specific correction base value is stored in the ROM 32 in advance when the engine 1 is manufactured. For this reason, ignition timing retardation control corresponding to the secular change of the engine 1 cannot be performed. For example, even when deposits accumulate in the cylinder and the compression ratio fluctuates, the cylinder-specific corrected base value is the compression ratio at the initial stage of engine manufacture (compression ratio when no deposit is accumulated). Accordingly, the basic ignition timing is corrected based on the above, and therefore, proper ignition timing retardation control cannot be performed. According to the present embodiment, not only the cylinder-by-cylinder correction base value but also the correction based on the added retardation correction amount is performed, so that it is possible to perform ignition timing retardation control corresponding to the secular change of the engine 1. Thereby, the fluctuation | variation of an output torque can be suppressed and the improvement of drivability can be aimed at.

-Other embodiments-
In the embodiment described above, the added retardation correction amount (αAKNK) is gradually obtained as a smaller value as the ratio of the current retardation correction amount (AKNK) to the maximum retardation amount (AKMAX) increases. The present invention is not limited to this, and the added retardation correction amount is set to a constant value until the ratio of the current retardation correction amount to the maximum retardation amount reaches a predetermined value. As the ratio of the current delay angle correction amount to the angle amount increases, the additional delay angle correction amount may be gradually obtained as a small value.

  Further, the magnitude of the current retardation correction amount used for obtaining the additional retardation correction amount is not limited to the ratio to the maximum retardation amount (a value that varies depending on the engine speed and the engine load factor). It is good also as a ratio with respect to a certain fixed value (value which does not change according to an engine speed or an engine load factor).

  Further, in the advance angle control operation in which the ignition timing is advanced after the occurrence of knocking is eliminated by the ignition timing delay angle control operation described above, the correction control width toward the advance angle side becomes smaller as the current delay angle correction amount increases. You may make it obtain as a value.

  In the above embodiment, the case where the present invention is applied to a port injection type in-line four-cylinder gasoline engine mounted on an automobile has been described. The present invention is not limited to this, and can be applied to other arbitrary number of cylinders such as a six-cylinder gasoline engine. Further, the present invention can be applied not only to the port injection type but also to an in-cylinder direct injection type engine. Moreover, application to a V-type engine, a horizontally opposed engine, etc. is also possible. Furthermore, the engine to which the present invention is applicable is not limited to an automobile engine.

  Further, the present invention can also be applied to a so-called hybrid vehicle in which an internal combustion engine and a traveling electric motor are mounted and the vehicle travels with one or both of the driving forces.

It is a figure showing a schematic structure of an engine concerning an embodiment. It is a figure which shows the outline of the control block of an engine. It is a flowchart figure which shows the procedure of the ignition timing retardation control at the time of knocking generation | occurrence | production.

Explanation of symbols

1 engine (internal combustion engine)
2 Spark plugs
27 Knock sensor (knocking detection means)

Claims (4)

In an ignition timing control device for an internal combustion engine that performs ignition delay control for retarding the ignition timing of the spark plug when knocking of the internal combustion engine occurs,
Current retard correction amount recognition means for recognizing the current retard correction amount of the ignition timing;
Knocking detection means for detecting that knocking has occurred in the internal combustion engine;
And an addition delay angle correction amount calculating means for receiving the outputs of the current delay angle correction amount recognition means and the knocking detection means and calculating an addition delay angle correction amount to be added to the current delay angle correction amount when knocking occurs. The ignition timing control device for an internal combustion engine, characterized in that the addition retardation correction amount calculating means is configured to calculate the addition retardation correction amount as a smaller value as the current retardation correction amount is larger. . In an ignition timing control device for an internal combustion engine that performs ignition delay control for retarding the ignition timing of the spark plug when knocking of the internal combustion engine occurs,
Current retard correction amount recognition means for recognizing the current retard correction amount of the ignition timing;
Knocking detection means for detecting that knocking has occurred in the internal combustion engine;
And an addition delay angle correction amount calculating means for receiving the outputs of the current delay angle correction amount recognition means and the knocking detection means and calculating an addition delay angle correction amount to be added to the current delay angle correction amount when knocking occurs. The ignition timing control device for an internal combustion engine, characterized in that the additional retard correction amount calculating means is configured to change the calculated additional retard correction amount according to the magnitude of the current retard correction amount. . The internal combustion engine ignition timing control device according to claim 1 or 2,
The internal combustion engine is a multi-cylinder internal combustion engine having a plurality of cylinders,
The additional retardation correction amount calculation means calculates the additional retardation correction amount by multiplying a cylinder-specific correction value preset for each cylinder by a variable set according to the magnitude of the current retardation correction amount. An ignition timing control device for an internal combustion engine, characterized in that: The ignition timing control device for an internal combustion engine according to claim 1, 2, or 3,
With respect to the reference ignition timing determined according to the operating state of the internal combustion engine, the added retard correction amount calculated by the added retard correction amount calculating means and the current retard correction recognized by the current retard correction amount recognizing means. An ignition timing control device for an internal combustion engine, characterized in that the final ignition timing is obtained by adding an amount to the retard side.

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