JP2009228656A - Control method for internal combustion engine, and internal combustion engine system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the merchantability of an internal combustion engine by eliminating rumble noise in an early stage. <P>SOLUTION: A vibration detection means 81 detects the vibration of an internal combustion engine body 1. The vibration detection means 81 detects the intensity A_GOS of the vibration in the preset first frequency band out of the vibration of the internal combustion engine body 1. When the intensity A_GOS of the vibration in the first frequency band exceeds the preset first reference intensity GOS_limit, the gas flow in a combustion chamber 17 of the internal combustion engine is reduced by the preset first reference quantity ΔTSCVa1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method and system for performing fuel control or air-fuel ratio control in response to vibration of an internal combustion engine body in a spark ignition internal combustion engine.

  Conventionally, various control methods for eliminating knocking have been developed for a spark ignition type internal combustion engine.

For example, Patent Document 1 detects vibrations caused by knocking of an internal combustion engine, and retards the ignition timing when vibrations of a predetermined intensity or higher are detected, while igniting to ensure output otherwise. A control method for advancing the timing to the knock limit is disclosed.
JP-A-52-87537

  In an internal combustion engine, particularly an internal combustion engine with a high compression ratio, the combustion in the combustion chamber becomes faster and the rate of increase in the combustion pressure becomes higher, so that the piston is hit with the combustion pressure, and the impact is transmitted to the crankshaft through the connecting rod. Rumble noise having a frequency lower than that of knocking vibration may occur. Since the rumble noise is transmitted to the user together with the knocking vibration, it is desired to eliminate the rumble noise in addition to the knocking cancellation in order to improve the merchantability of the internal combustion engine. However, the conventional method is merely a control method for eliminating knocking, and even if this method is used, it is not possible to eliminate rumble noise having a different generation principle from knocking.

  In view of such circumstances, an object of the present invention is to provide a control method for an internal combustion engine that can eliminate rumble noise at an early stage and increase the commerciality of the internal combustion engine.

  The invention according to claim 1 for solving the above-mentioned problem uses a vibration detection means for detecting the vibration of the internal combustion engine body, and a first frequency band preset among the vibrations of the internal combustion engine body by the vibration detection means. When the vibration intensity of the first frequency band exceeds a first reference intensity set in advance, the gas flow in the combustion chamber of the internal combustion engine is set to a first preset value. The method includes a step of reducing the reference amount (claim 1).

  According to this method, it is possible to detect whether or not rumble noise is generated by the vibration detection means, and to reduce rumble noise at an early stage by reducing the gas flow in the combustion chamber. Can increase the merchantability. That is, the rumble noise is generated when the combustion speed is high and the increase rate of the combustion pressure is high. Therefore, if the gas flow in the combustion chamber is reduced as in the present method, the combustion speed can be reduced, and the generated rumble noise can be eliminated at an early stage.

  In the present invention, it is preferable to retard the ignition timing for the gas in the combustion chamber when the intensity of vibration in the first frequency band exceeds the first reference intensity.

  In this way, combustion can be slowed down and the occurrence of rumble noise can be eliminated earlier.

  In the present invention, the vibration detecting means detects the intensity of vibration in a second frequency band set in advance that is higher than the first frequency band among the vibrations of the main body of the internal combustion engine. Preferably, the method includes a step of increasing the gas flow in the combustion chamber of the internal combustion engine by a second reference amount set in advance when the vibration intensity exceeds a second reference strength set in advance (Claim 3). .

  In this way, knocking can be eliminated at an early stage in addition to rumble noise, and the merchantability of the internal combustion engine can be further enhanced. That is, knocking, which is vibration in the second frequency band higher than rumble noise, is likely to occur when the flame propagation time is long. Therefore, if the vibration intensity in the second frequency band exceeds the preset second reference intensity as in the present method, that is, if knocking occurs, the gas flow in the combustion chamber is increased and the combustion speed is increased. Can be increased to shorten the flame propagation time, and the knocking that has occurred can be eliminated early.

  Further, the present invention preferably includes a step of retarding the ignition timing for the gas in the combustion chamber when the intensity of vibration in the second frequency band exceeds the second reference intensity. .

  If it does in this way, combustion temperature can be reduced and generation | occurrence | production of knocking can be eliminated earlier.

  In the present invention, when the vibration intensity in the first frequency band exceeds the first reference intensity and the vibration intensity in the second frequency band exceeds the second reference intensity, It is preferable to include a step of retarding the ignition timing for the gas and changing the gas flow in the combustion chamber of the internal combustion engine by an amount smaller than the first reference amount and the second reference amount.

  In this way, both the knocking and the rumble noise can be suppressed small by retarding the ignition timing, and excessive deterioration of either one can be suppressed by finely adjusting the gas flow. .

  Here, a specific method for changing the gas flow in the combustion chamber is not particularly limited. For example, the flow control valve provided in an intake port communicating with the combustion chamber is used to open the flow of the flow control valve. What is necessary is just to change the gas flow in the said combustion chamber by increase / decrease of (Claim 6).

  The present invention also relates to an internal combustion engine system including a spark ignition type internal combustion engine, a vibration detection means for detecting vibration of the internal combustion engine body, and a vibration intensity of the internal combustion engine body detected by the vibration detection means. And a flow control means for changing the gas flow in the combustion chamber of the internal combustion engine in response to the vibration, wherein the flow control means is a first preset among vibrations of the internal combustion engine body detected by the vibration detection means. An internal combustion engine system is provided, wherein the gas flow in the combustion chamber is reduced by a first reference amount set in advance when the vibration intensity in the frequency band exceeds a first reference strength set in advance (claim). Item 7).

  According to this internal combustion engine system, the rumble noise can be eliminated early by reducing the combustion speed when the rumble noise occurs.

  The flow control means has a vibration intensity of the second frequency band set in advance that is higher than the first frequency band among the vibrations of the internal combustion engine body detected by the vibration detection means. If it is configured to increase the gas flow in the combustion chamber by a second reference amount set in advance when exceeding the two reference strengths, knocking can be suppressed in addition to rumble noise. .

  Here, as a specific configuration of the flow control means, a flow control valve provided in an intake port communicating with the combustion chamber and capable of changing a gas flow amount of the intake port, the opening degree of the flow control valve is provided. The gas flow in the combustion chamber may be changed by increasing or decreasing (Claim 9).

  In the internal combustion engine system, the vibration detection means detects first vibration detection means for detecting vibrations in the first frequency band of the internal combustion engine body and first vibration detection means for detecting vibrations in the second frequency band of the internal combustion engine body. Two vibration detection means, wherein the first vibration detection means is closer to the crankshaft of the internal combustion engine than the second vibration detection means, and the second detection means is a cylinder of the internal combustion engine more than the first detection means. It is preferable to be arranged close to the head (claim 10).

  The rumble noise that is the vibration in the first frequency band is the vibration of the crankshaft. Knocking, which is vibration in the second frequency band, is resonance vibration of pressure in the combustion chamber. Therefore, if the second vibration detecting means for detecting the knocking is arranged on the cylinder head side and the first vibration detecting means for detecting the rumble noise is arranged in the vicinity of the crankshaft, the detecting means can knock and rumble more accurately. Noise can be detected.

  As described above, according to the present invention, rumble noise can be more reliably eliminated, and the merchantability of the internal combustion engine can be improved.

  A preferred embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 schematically shows the overall structure of an engine system (internal combustion engine system) to which the present invention is applied. The engine system includes an engine main body (internal combustion engine) 1 and an engine controller (including flow control means) 100 for controlling various actuators attached to the engine main body 1.

  The engine body 1 is a four-cycle spark ignition type internal combustion engine mounted on a vehicle such as an automobile, and its output shaft is coupled to drive wheels via a transmission to propel the vehicle. The engine body 1 includes a cylinder block 12 and a cylinder head 13 placed thereon. A plurality of cylinders 11 are formed inside the cylinder block 12 and the cylinder head 13. Although the number of these cylinders 11 is not specifically limited, For example, four cylinders 11 are formed. A crankshaft 14 is rotatably supported on the cylinder block 12 by a journal, a bearing or the like.

  A piston 15 is slidably fitted in each cylinder 11, and a combustion chamber 17 is defined above each piston 15.

  As shown in FIG. 2, the cylinder head 13 is formed with two intake ports 18 a and 18 b and two exhaust ports 19 a and 19 b communicating with each combustion chamber 17. The cylinder head 13 includes an intake valve 21 for shutting off the intake ports 18a and 18b from the combustion chamber 17, and an exhaust valve for shutting off the exhaust ports 19a and 19b from the combustion chamber 17, respectively. 22 are provided. The intake valve 21 is driven by an intake valve drive mechanism 30 described later to open and close the intake ports 18a and 18b at a predetermined timing. On the other hand, the exhaust valve 22 is driven by an exhaust valve drive mechanism 40 described later to open and close the exhaust ports 19a and 19b.

  The intake valve drive mechanism 30 and the exhaust valve drive mechanism 40 have an intake camshaft 31 and an exhaust camshaft 41, respectively. The intake camshaft 31 and the exhaust camshaft 41 are connected to the crankshaft 14 via a known power transmission mechanism such as a chain / sprocket mechanism.

  The intake valve drive mechanism 30 includes a valve timing of the intake valve 21 between the power transmission mechanism and the intake camshaft 31 based on a valve timing of the intake valve 21 calculated by an engine controller 100 described later. An intake camshaft phase varying mechanism 32 is provided for changing the above.

  The exhaust valve drive mechanism 40 is also provided with an exhaust camshaft phase varying mechanism 42 between the power transmission mechanism and the exhaust camshaft 41. The exhaust camshaft phase varying mechanism 42 changes the valve timing of the exhaust valve 22.

  The intake ports 18 a and 18 b communicate with the surge tank 55 a through the intake manifold 55. A throttle body 56 is provided in the intake passage upstream of the surge tank 55a. Inside the throttle body 56, a throttle valve 57 for adjusting the intake air flow rate from the outside toward the surge tank 55a is pivotally provided. The throttle valve 57 can change the flow rate of the intake pipe passage to change the intake flow rate, and can change the pressure in the intake pipe passage downstream of the throttle valve 57. The throttle valve 57 is driven by a throttle actuator 58. The throttle actuator 58 drives the throttle valve 57 so that the opening degree of the throttle valve 57 becomes a throttle opening degree TVO calculated by the engine controller 100 described later. In the present embodiment, the amount of air charged in the combustion chamber 17 is controlled to an appropriate value by adjusting the opening of the throttle valve 57 and the valve timing of the intake valve 21.

As shown in FIG. 2, a tumble swirl control valve (flow control valve, hereinafter referred to as TSCV) 82 is disposed in one of the intake ports 18a and 18b. This TSCV 82 increases the flow velocity of intake air from the other intake port 18b toward the combustion chamber 17 by reducing the flow passage area of one intake port 18a, and the gas flow in the combustion chamber 17 is increased in the combustion chamber 17. In addition, a lateral swirl flow or swirl and a vertical swirl flow or tumble can be generated. The TSCV 82 is driven by a TSCV actuator 84 to change its opening. The TSCV actuator 84 drives the TSCV 82 so that the opening degree of the _{TSCV 82} becomes a TSCV final target opening degree θ _TSCVe calculated by the engine controller 100 described later, thereby adjusting the gas flow in the cylinder to an appropriate state. To do. Specifically, when the TSCV final target opening θ _TSCVe is 0%, the TSCV actuator 84 fully closes the TSCV 82 to increase the gas flow, that is, strengthen the gas flow. Then, as the TSCV final target opening degree θ _TSCVe increases, the TSCV 82 is opened to decrease the gas flow. When the TSCV final target opening degree θ _TSCVe is 100%, the TSCV 82 is fully opened.

  The exhaust ports 19 a and 19 b communicate with an exhaust pipe via an exhaust manifold 60. An exhaust gas purification system is disposed in the exhaust pipe. The specific configuration of the exhaust gas purification system is not particularly limited, and examples thereof include those having a catalytic converter 61 such as a three-way catalyst, a lean NOx catalyst, and an oxidation catalyst.

  The intake manifold 47 and the exhaust manifold 60 communicate with each other through an EGR pipe 62, and a part of the exhaust gas is circulated to the intake side. The EGR pipe 62 is provided with an EGR valve 63 for adjusting the flow rate of EGR gas that circulates through the EGR pipe 62 to the intake side. The EGR valve 63 is driven by an EGR valve actuator 64. The EGR valve actuator 64 drives the EGR valve 63 so that the opening degree of the EGR valve 63 becomes an EGR opening degree EGRopen calculated by the engine controller 100 described later, thereby appropriately adjusting the flow rate of the EGR gas. Adjust to a correct value.

  A spark plug 51 is attached to the cylinder head 13 so that the tip thereof faces the combustion chamber 17. The spark plug 51 generates a spark in the combustion chamber 17 when energized by the ignition system 52 based on a signal timing SA of an ignition timing calculated by an engine controller 100 described later.

  In addition, a fuel injection valve 53 for directly injecting fuel into the combustion chamber 17 is attached to the cylinder head 13 so that the tip thereof faces the combustion chamber 17. More specifically, the fuel injection valve 53 has a leading end positioned below the two intake ports 18a and 18b in the vertical direction and in the middle of the two intake ports 18a and 18b in the horizontal direction. It is arranged to be located. The fuel injection valve 53 is energized for a predetermined period based on a signal of a fuel injection pulse amount FP calculated by an engine controller 100 described later by a fuel system 54 by a solenoid provided in the fuel injection valve 53. A predetermined amount of fuel is injected into the combustion chamber 17.

  A first vibration sensor (first vibration detection means) 81 and a second vibration sensor (second vibration detection means) 80 for detecting vibration of the cylinder block are attached to the cylinder block 12. The first vibration sensor 81 is disposed as close as possible to the crankshaft 14 that is a source of rumble noise in order to mainly detect rumble noise. And this 1st vibration sensor 81 is comprised so that the vibrator | oscillator may be displaced to a perpendicular direction (up-down direction in FIG. 1) so that the vibration direction of a rumble noise may be followed as much as possible. On the other hand, the second vibration sensor 80 is disposed at a position as close as possible to the combustion chamber 17, that is, a position close to the cylinder head 13 in order to detect knocking mainly generated in the combustion chamber 17. And this 2nd vibration sensor 80 is comprised so that the vibrator | oscillator may be displaced to a horizontal direction (left-right direction in FIG. 1) so that it may follow the propagation direction of knocking vibration as much as possible.

  The knocking is a high-frequency vibration indicated by A in the waveform of the in-cylinder pressure P with respect to the crank angle in FIG. Those configured to be able to detect relatively accurately are used. In addition, knocking is resonance vibration of the pressure in the combustion chamber 17, and in the present embodiment, the second vibration sensor 80 is attached in the vicinity of the combustion chamber 17 so that knocking is accurately detected by the second vibration sensor 80. . The vibration signal detected by the second vibration sensor 80 is applied to the bandpass filter of the second frequency band and then input to the engine controller 100 described later. Then, the engine controller 100 calculates the strength of the vibration KNS in the second frequency band as the knocking strength A_KNS.

  On the other hand, as shown in FIG. 3, the rumble noise is a vibration generated when the maximum value dP / dθ_max of the increase rate of the combustion pressure becomes too high and the impact when the piston 15 is struck with the combustion pressure is transmitted to the crankshaft 14. In particular, the vibration is generated as a result of the crankshaft 14 being bent by the impact, and is a low-frequency vibration compared to knocking. Therefore, in the present embodiment, the first vibration sensor 81 is configured to detect vibrations in a low frequency band (first frequency band) lower than the second frequency band with relatively high accuracy, By attaching the first vibration sensor 81 below the second vibration sensor 80 and in the vicinity of the crankshaft 14, rumble noise is detected with high accuracy. The vibration signal detected by the first vibration sensor 81 is applied to the bandpass filter of the first frequency band and then input to the engine controller 100 described later. The engine controller 100 calculates the intensity of the vibration GOS in the first frequency band as the rumble noise intensity A_GOS.

  The engine controller 100 is a controller based on a well-known microcomputer, and performs input / output of various signals, a CPU for executing a program, a memory including a RAM and a ROM for storing the program and data, and the like. And an I / O bus.

The engine controller 100 includes an intake air amount AF detected by an air flow meter 71, an air pressure MAP in the intake manifold 55 detected by an intake pressure sensor 72, and an intake air temperature sensor 78 via the I / O bus. The engine air temperature T _ENG detected by the water temperature sensor 77, the crank angle pulse signal detected by the crank angle sensor 73, and the exhaust gas detected by the oxygen concentration sensor 74. The oxygen concentration EGO of the vehicle, the accelerator pedal depression amount α detected by the accelerator opening sensor 75, the vehicle speed VSP detected by the vehicle speed sensor 76, and the advance amount of the intake valve 21 detected by the cam angle sensor 35 θ _{VCT_i_A,} detection by said second vibration sensor 80 Vibration signal KNS the second frequency band of the cylinder block 12, various kinds of information such as the vibration signal GOS of the second frequency band of the cylinder block 12 detected by the first vibration sensor 81 are inputted.

The engine controller 100 calculates command values for various actuators based on the input information. For example, command values such as throttle opening TVO, fuel injection pulse amount FP, ignition timing timing SA, TSCV target opening θ _TSCV , intake valve timing θ _{VCT_i_D} , exhaust valve timing θ _{VCT_e_D} , EGR opening EGR _open are calculated, They are output to the throttle actuator 58, fuel system 54, ignition system 52, TSCV actuator 84, intake camshaft phase variable mechanism 32, exhaust camshaft phase variable mechanism 42, EGR valve actuator 64, and the like. In particular, the engine controller 100 calculates the knocking strength A_KNS that is the strength of the second vibration signal KNS and the rumble noise strength A_GOS that is the strength of the first vibration signal GOS, and calculates the knocking strength A_KNS and the rumble noise strength A_GOS. Based on this, correction control of the ignition timing SA and correction of the TSCV target opening θ _TSCV are performed.

  A specific calculation procedure in the engine controller 100 will be described with reference to the flowchart of FIG.

  First, various signals such as the accelerator pedal depression amount α are read (step S1).

Next, a target torque TQ _D is calculated based on the accelerator pedal depression amount α, the engine body speed N _ENG calculated from the crank angle pulse signal, and the vehicle speed VSP (step S2). Based on the calculated target torque TQ _D and the rotational speed N _ENG , the target air filling amount CE _D and the fuel injection amount FP are calculated (step S4).

Then, based on the rotational speed _{N ENG} the target air charge amount CE _D calculated in the step S3, the target value theta _{VCT_i_D} the valve timing of the intake valve 21, the target value theta _{VCT_e_D} the valve timing of the exhaust valve 22 and to calculate a target value TVO _D of opening TVO of the throttle valve 57 (step S6).

On the other hand, based on the calculated target torque TQ _D and the rotational speed N _ENG , a reference TSCV target opening degree θ _{TSCV_base} and a reference ignition timing SA_base are calculated (step S7). Thereafter, a TSCV target opening correction amount (hereinafter referred to as a TSCV correction amount) TSCVa and an ignition timing advance correction amount Igt are calculated (step S8), and the calculated reference TSCV target opening θ _{TSCV_base} and the TSCV correction amount are calculated. A TSCV final target opening θ _TSCVe is calculated from TSCVa, and a final ignition timing SAe is calculated from the calculated reference ignition timing SA_base and the ignition timing advance correction amount Igt (step S9). Details of the calculation method of the TSCV correction amount TSCVa and the ignition timing advance correction amount Igt will be described later.

Thereafter, the calculated TSCV final target opening theta _TSCVe, the final ignition timing SAe, fuel injection amount FP, a target value theta _{VCT_i_D} of the valve timing of the intake valve 21, the target value theta _{VCT_e_D} the valve timing of the exhaust valve 22, the throttle valve 57 based on the target value TVO _D of opening TVO, these target values to drive the actuators as satisfied (step S10).

Specifically, the signal θ _{VCT_i_D} is output to the intake camshaft phase varying mechanism 32. Then, the intake camshaft phase varying mechanism 32 operates so that the phase of the intake camshaft 31 with respect to the crankshaft 14 has a value corresponding to _{θVCT_i_D} . The signal θ _{VCT_e_D} is output to the exhaust camshaft phase varying mechanism 42. Then, the exhaust camshaft phase varying mechanism 42 operates so that the phase of the exhaust camshaft 41 with respect to the crankshaft 14 has a value corresponding to _{θVCT_e_D} . Signal TVO _D is transmitted to the throttle actuator 58. Then, the opening degree TVO of the throttle valve 57 is such that the value corresponding to the TVO _D, the throttle actuator 58 is operated. The signal θ _TSCVe is output to the TSCV actuator 84. The TSCV actuator 84 operates so that the opening degree of the _TSCV becomes a value corresponding to θTSCVe. The signal FP is output to the fuel system 54. An amount of fuel corresponding to FP per cylinder cycle is injected from the fuel injection valve 53. Then, the signal SAe is output to the ignition system 52. At a time corresponding to SAe in the cylinder cycle, the spark plug 51 ignites and ignites the air-fuel mixture in the combustion chamber 17. As a result, a target torque mainly determined from the depression amount α of the accelerator pedal is generated from the engine body 1 by igniting and burning the required amount of air / fuel mixture at an appropriate time. Is done.

  Next, a specific method for calculating the TSCV correction amount TSCVa and the ignition timing advance correction amount Igt will be described with reference to the flowcharts of FIGS.

First, it is determined whether or not each correction execution condition is satisfied (step S22). The specific contents of this execution condition are not particularly limited. For example, the rotational speed N _ENG , the target torque TQ _D , the air charge amount CE, the engine coolant temperature T _ENG , and the intake air temperature Tm are within a predetermined range. If the execution of each correction is permitted only when the driving conditions are likely to cause knocking and rumble noise, it is possible to more reliably avoid erroneous correction associated with knocking or erroneous detection of rumble noise. Specifically, there are operating conditions such that the rotational speed N _ENG is 3000 rpm or less, the charging efficiency is 0.5 or more, the engine cooling water temperature T _ENG is 60 ° C. or more, and the intake air temperature Tm is 35 ° C. or more. When the determination is NO, that is, when the execution condition is not satisfied, the values of the TSCV correction amount TSCVa and the advance angle correction amount Igt are set to 0, and the process is terminated. On the other hand, if the determination is YES, that is, if the execution condition is satisfied, the knocking strength A_KNS and the rumble noise strength A_GOS calculated separately are received (step S26). Then, the knocking limit ratio r_KNS used in the subsequent calculation is calculated from r_KNS = A_KNS / KNSlimit. The KNSlimit is a preset knocking limit (second reference strength), and the knocking limit ratio r_KNS represents the current knocking strength with respect to the knocking limit KNSlimit. Similarly, a rumble noise limit ratio r_GOS representing the current rumble noise intensity with respect to the rumble noise limit (first reference intensity) GOSlimit is calculated from r_GOS = A_GOS / GOSlimit (step S28). In the present embodiment, the knocking intensity and the rumble noise intensity are compared using the respective limit ratios r_KNS and r_GOS normalized by these limit values.

  Next, it is determined whether the value of the knocking strength A_KNS is less than or equal to the knocking limit KNSlimit and whether the value of the rumble noise strength A_GOS is less than or equal to the rumble noise limit GOSlimit (step S30). If the determination in step S30 is YES, it is further determined whether or not the value of the knocking strength A_KNS is larger than the knocking limit KNSlimit-K1 and the value of the rumble noise strength A_GOS is larger than the rumble noise limit GOSlimit-K2. Determine (step S70). K1 and K2 are predetermined values set in advance. If the determination in step S70 is YES, it is assumed that knocking and rumble noise are almost limits and appropriate control is being performed, and the processing is terminated with the advance angle correction amount Igt and the TSCV correction amount TSCVa as the previous calculated values, respectively. (Igt = Igt (I-1), TSCVa = TSCVa (I-1)) (step S71). Igt (I-1) is the advance correction amount calculated last time, and is reset to 0 when the operating condition changes. TSCVa (I-1) is the previously calculated TSCV correction amount TSCVa, and is reset to 0 when the operating condition changes.

  If the determination in step S70 is NO, assuming that knocking and rumble noise have not occurred, the advance correction amount Igt is increased to advance the ignition timing SA, and the output from the engine body 1 is increased. (Step S31). Specifically, the advance angle correction amount Igt is calculated as Igt = Igt (I-1) + ΔIgt. ΔIgt is an increase amount per cycle of the advance correction amount Igt, and is a positive value.

  Thereafter, it is determined whether the rumble noise limit ratio r_GOS is larger than the knock limit ratio r_KNS (step S32). If this determination is YES, that is, if it is determined that the rumble noise intensity A_GOS is larger than the knocking intensity A_KNS and the margin for the limit is smaller, the TSCV correction amount TSCVa is set to a preset third correction. By increasing the amount ΔTSCVa1 (TSCVa = TSCVa (I−1) + ΔTSCVa1), the TSCV 82 is corrected to the open side, and the gas flow in the combustion chamber 17 is decreased by a predetermined amount (step S33). TSCVa (I-1) is a previously calculated TSCV correction amount, and is reset to 0 when the operating condition changes. The first correction amount ΔTSCVa1 is an increase amount per cycle of the TSCV correction amount TSCVa and is a positive value.

  Here, as described above, the rumble noise is generated when the maximum value dP / dθ_max of the increase rate of the combustion pressure becomes too high. Therefore, the increase rate of the combustion pressure is reduced by reducing the combustion speed. If it is reduced, the rumble noise intensity can be reduced. As shown in FIG. 7, the MBT advances as the TSCV 82 is controlled to open, and if the TSCV 82 is controlled to open, the combustion speed decreases as the gas flow in the combustion chamber 17 decreases. descend. Therefore, the engine controller 100 corrects the TSCV 82 to the open side as described above to reduce the gas flow in the combustion chamber 17 to reduce the combustion speed, thereby reducing the rumble noise intensity with a small margin to the limit. Keep it to a smaller value. FIG. 8 shows the relationship between the TSCV opening degree and the rumble noise margin, which is the advanceable amount until rumble noise is generated with respect to the angle at which knocking occurs. As is apparent from this figure, when the TSCV 82 is controlled to the open side, rumble noise is less likely to occur.

  On the other hand, if the determination in step S32 is NO and the rumble noise limit ratio r_GOS and the knocking limit ratio r_KNS match, that is, it is determined that the rumble noise intensity A_GOS and the knocking intensity A_KNS are equivalent to the reference. If YES (YES in step S34), the TSCV correction amount TSCVa is not increased or decreased, and the previous TSCV correction amount is maintained (TSCVa = TSCVa (I-1)) (step S35).

  If the determination in step S32 is NO and the rumble noise limit ratio r_GOS and the knock limit ratio r_KNS do not match, that is, the knocking intensity A_KNS is larger than the rumble noise intensity A_GOS, and there is a margin for the limit. If it is determined that it is small (NO in step S34), the TSCV correction amount TSCVa is decreased by the fourth correction reference amount ΔTSCVa1 (TSCVa = TSCVa (I−1) −ΔTSCVa1), and the TSCV 82 is closed. Correction is made to strengthen the gas flow in the combustion chamber 17 by a predetermined amount (step S36). Here, the third correction reference amount for increasing the TSCV opening in step S33 and the fourth correction reference amount for decreasing TSCV in step S36 may be set to different values. In the form, the same value ΔTSCVa1 is set.

  Here, since knocking occurs when the flame propagation time is long, the knocking strength is reduced by increasing the combustion speed and shortening the flame propagation time. Therefore, in the engine controller 100, as described above, the TSCV 82 is corrected to the closed side to enhance the gas flow in the combustion chamber 17 to increase the combustion speed, and the knocking strength with a small margin with respect to the limit is set to a smaller value. Keep it down.

  As described above, in the present embodiment, even when the rumble noise strength A_GOS knocking strength A_KNS is less than or equal to the respective limits GOSlimit and KNSlimit, the noise strength of the larger strength is suppressed to a small value, thereby reducing the rumble noise. And knocking can be balanced. That is, it is possible to avoid a biased combustion state in which one of the noise intensities increases.

  On the other hand, when the step S30 is NO, it is next determined whether or not the value of the knocking strength A_KNS is equal to or less than the knocking limit KNSlimit and the value of the rumble noise strength A_GOS is greater than the rumble noise limit GOSlimit. (Step S40).

  If the determination in step S40 is yes, knocking has not occurred but rumble noise has occurred, and the advance correction amount Igt is reduced (Igt = Igt (I-1) -ΔIgt). While retarding the ignition timing, the TSCV correction amount TSCVa is increased by the first correction reference amount ΔTSCVa1 (TSCVa = TSCVa (I−1) + ΔTSCVa1), the TSCV 82 is corrected to the open side, and the combustion chamber 17 The gas flow is reduced by a predetermined amount (first reference amount) (step S42). As described above, the rumble noise is generated when the maximum value dP / dθ_max of the increase rate of the combustion pressure becomes too high. Therefore, if the ignition timing SA is corrected to be retarded as described above, combustion is not performed. It becomes possible to suppress the generation of rumble noise by slowing down and decreasing the increase rate of the combustion pressure. In this way, in the engine controller 100, when rumble noise occurs, the rumble noise can be eliminated early by delaying the ignition timing SA in addition to correcting the TSCV.

  If the determination in step S40 is NO, it is further determined whether or not the value of the knocking strength A_KNS is greater than the knocking limit KNSlimit and the value of the rumble noise strength A_GOS is less than or equal to the rumble noise limit GOSlimit. Determination is made (step S50). If the determination in step S50 is YES, it is determined that knocking has occurred but no rumble noise has occurred, and the advance correction amount Igt is reduced (Igt = Igt (I-1) −Δ Igt) The ignition timing is retarded and the TSCV correction amount TSCVa is decreased by the second reference correction amount ΔTSCVa1 (TSCVa = TSCVa (I−1) −ΔTSCVa1), the TSCV 82 is corrected to the close side, and combustion is performed. The gas flow in the chamber 17 is strengthened by a predetermined amount (second reference amount) (step S52). As described above, knocking occurs when the temperature in the combustion chamber 17 is high or the flame propagation time is long. Therefore, if the ignition timing SA is corrected to be retarded as described above, the maximum pressure and temperature in the combustion chamber 17 are reduced, so that the occurrence of knocking can be suppressed. In this way, in the engine controller 100, when knocking occurs, knocking can be eliminated early by correcting the ignition timing SA to be retarded in addition to the correction of the TSCV 82. Here, the first reference correction amount and the second reference correction amount may be set to different values. In the present embodiment, the first reference correction amount and the second reference correction amount are set to the same value ΔTSCVa1 and the first reference correction amount. The third reference correction amount and the fourth reference correction amount are set to the same value.

  If the determination in step S50 is NO, it is confirmed again whether the execution condition is satisfied (step S60). If this execution condition is satisfied (YES in step S60), it is determined that both knocking and rumble noise have occurred, and the advance angle correction amount Igt is reduced (Igt = Igt (Igt -1) -.DELTA.Igt) The ignition timing SA is retarded (step S61). On the other hand, with respect to the TSCV correction amount TSCVa, the rumble noise limit ratio r_GOS and the knock limit ratio r_KNS are compared with each other in the same manner as in Steps S32 to S36, and correction according to the larger intensity is performed. That is, when it is determined that the rumble noise limit ratio r_GOS is larger than the knock limit ratio r_KNS and the rumble noise intensity A_GOS is larger than the knock intensity A_KNS (YES in step S62), The TSCV correction amount TSCVa is increased by the fifth correction reference amount ΔTSCVa2 (TSCVa = TSCVa (I−1) + ΔTSCVa2), the TSCV 82 is corrected to the open side, and the gas flow in the combustion chamber 17 is decreased by a predetermined amount. This suppresses rumble noise (step S63). On the other hand, when it is determined that the rumble noise limit ratio r_GOS is smaller than the knock limit ratio r_KNS and the knocking intensity A_KNS is larger than the rumble noise intensity A_GOSS (NO in step S62 and step S64). NO), the TSCV correction amount TSCVa is decreased by the sixth correction reference amount ΔTSCVa2 (TSCVa = TSCVa (I−1) −ΔTSCVa2), the TSCV 82 is corrected to the close side, and the inside of the combustion chamber 17 is corrected. By suppressing the gas flow by a predetermined amount, knocking is suppressed (step S66). If the rumble noise limit ratio r_GOS and the knock limit ratio r_KNS are equal (NO in step S62 and YES in step S64), the TSCV correction is not performed and the previous TSCV correction amount is maintained as the correction amount TSCVa. (TSCVa = TSCVa (I-1)) (Step S65).

  In this way, in the engine controller 100, when rumble noise and knocking occur at the same time, the ignition timing SA is retarded to suppress both occurrences, and the intensity exceeds the standard. By correcting the TSCV 82 so as to resolve the problem first, discomfort to the user or the like can be reduced earlier. Here, the values of the fifth correction reference amount and the sixth correction reference amount ΔTSCVa2, which are the increase / decrease amounts of the TSCV correction amount in the steps S63 and S66, are smaller than the values of ΔTSCVa1 such as the first correction reference amount. The increase and decrease in gas flow in step S63 and step S66 are smaller than the increase and decrease in gas flow in step S42 and step S52. As a result, in the present embodiment, it is possible to suppress the other deterioration margin when the TSCV 82 is corrected in a direction to suppress either rumble noise or knocking. The fifth correction reference amount and the sixth correction reference amount may be different values.

The advance angle correction amount Igt and the TSCV correction amount TSCVa calculated as described above are added to the reference TSCV target opening θ _{TSCV_base} and the reference ignition timing SA_base, respectively, in step S9, and the TSCV final target opening TSCVe and This is reflected in the final ignition timing SAe.

  Here, upper and lower limits are set for the advance angle correction amount Igt and the TSCV correction amount TSCVa, respectively, and the advance angle correction amount Igt and the TSCV correction amount TSCVa calculated in steps S33 to S66 have the upper and lower limits. If it exceeds, the upper and lower limit values will be corrected. Further, the upper and lower limit values, the knocking limit KNSlimit and the rumble noise limit GOSlimit, and the reference correction amounts ΔTSCVa1 and ΔTSCVa2 are set to different values for each operating condition, and appropriate control is performed according to the operating condition. The

  FIG. 9 and FIG. 10 show examples of control results relating to the correction of the TSCV injection amount TSCVa and the advance correction of the ignition timing SA. FIG. 9 is a control result under conditions where rumble noise is more likely to occur than knocking, and FIG. 10 is a control result under conditions where knocking is more likely to occur than rumble noise. Each figure shows changes in the TSCV correction amount TSCVa, the advance angle correction amount Igt, and the limit ratio (knocking limit ratios r_KNS, r_GOS) with respect to the engine cycle. Here, regarding the limit ratio, the knocking intensity and the rumble noise intensity are represented on the same graph for easy display.

  First, FIG. 9 will be described. Until the engine cycle C11, the knocking limit ratio r_KNS and the rumble noise limit ratio r_GOS are both 1 or less, and the knocking intensity A_KNS and the rumble noise intensity A_GOS are both less than the knocking limit KNSlimit and the rumble noise limit GOSlimit. And since knocking intensity | strength A_KNS is below KNSlimit-K1, in this period, it determines with YES by said step S30, determines with NO by step S70, and performs control of said step S31. That is, the advance correction amount Igt is increased, and the ignition timing SA is sequentially advanced by ΔIgt. Also, during this period, the rumble noise limit ratio r_GOS is larger than the knock limit ratio r_KNS, so that it is determined YES in step S32, and the control for increasing the TSCV correction amount TSCVa, which is the control in step S33, is performed. TSCV is corrected to the open side.

  When the ignition timing SA is corrected to advance, the intensity of knocking and rumble noise increases. As a result, in the engine cycle C11, the rumble noise limit ratio r_GOS exceeds 1, and the rumble noise intensity A_GOS exceeds the rumble noise limit GOSlimit.

  If the rumble noise intensity A_GOS exceeds the rumble noise limit GOSlimit under the condition that the knocking intensity A_KNS is equal to or less than the knocking limit KNSlimit, it is determined NO in step S30 and YES in step S40, and the control in step S42 is performed. In other words, in the engine cycle C12, the advance correction amount Igt is decreased to retard the ignition timing SA, and the TSCV 82 is further corrected to the opening side by increasing the TSCV correction amount TSCVa. As a result, the rumble noise limit ratio r_GOS decreases to 1 or less. If the rumble noise limit ratio r_GOS decreases to 1 or less and it is determined that the rumble noise intensity A_GOS is less than or equal to the rumble noise limit GOSlimit, YES is determined again in step S30. The knocking strength A_KNS is still less than or equal to KNSlimit-K1, and the rumble noise limit ratio r_GOS is greater than the knocking limit ratio r_KNS. Therefore, NO is determined in step S70 and YES is determined in step S32, and is equivalent to the engine cycle C11. Control is implemented.

  In this way, the ignition timing SA is advanced in the period from the engine cycle C11, the period from the engine cycle C12 to the engine cycle C13, and the period from the engine cycle C14 to the engine cycle C15 (step S31). The TSCV 82 is corrected to the open side (step S33). In the engine cycles C12, C14, and C16, only the rumble noise limit ratio r_GOS exceeds 1 and the rumble noise intensity A_GOS exceeds the rumble noise limit GOSlimit with the correction (NO in step S30 and YES in step S40). Then, the ignition timing SA is corrected to be retarded and the TSCV 82 is corrected to the open side (step S42).

  Then, in the engine cycle C16 in which the ignition timing SA is corrected by a predetermined amount and the TSCV 82 is corrected to open by a predetermined amount, the rumble noise limit ratio r_GOS and the knocking noise limit ratio r_KNS are both 1 or less near 1. That is, when both the rumble noise intensity A_GOS and the knocking noise intensity A_KNS are equal to or less than the limit values in the vicinity of the limit values and the respective limit ratios are equal to each other, it is determined YES in step S30 and step S70. Proceeding to step S71, the correction of each correction amount is completed.

  Next, FIG. 10 will be described. Until the engine cycle C21, the knocking limit ratio r_KNS and the rumble noise limit ratio r_GOS are both 1 or less, and the advance angle correction amount Ig is corrected in the same manner as in the period up to C11 in FIG. In other words, YES is determined in step S30 and NO is determined in step S70. As a result, the advance correction amount Igt is increased, and the ignition timing SA is sequentially advanced by ΔIgt. Further, during this period, the knocking limit ratio r_KNS is larger than the rumble noise limit ratio r_KNS, so that NO is determined in step S32 and NO is determined in step S34, and control for reducing the TSCV correction amount TSCVa, which is the control in step S36. Is executed, and the TSCV 82 is corrected to the open side.

  When the ignition timing SA is corrected to advance, the intensity of knocking and rumble noise increases. As a result, in engine cycle C21, knocking noise limit ratio r_KNS exceeds 1, and knocking intensity A_KNS exceeds knocking limit KNSlimit.

  If the knocking strength A_KNS exceeds the knocking limit KNSlimit under the condition that the rumble noise strength A_GOS is equal to or less than the rumble noise limit GOSlimit, NO is determined in steps S30 and S40 and YES is determined in step S50, and the control in step S52 is performed. The That is, in the engine cycle C22, the advance correction amount Igt is decreased to retard the ignition timing SA, and the TSCV correction amount TSCVa is corrected to decrease, whereby the TSCV 82 is further corrected to the closing side. As a result, knocking limit ratio r_KNS is reduced to 1 or less. When knocking limit ratio r_KNS is reduced to 1 or less and knocking strength A_KNS is determined to be equal to or less than knocking limit KNSlimit, it is determined again as YES in step S30. Since the rumble noise intensity A_GOS is still less than GOSlimit-K2 and the knocking limit ratio r_KNS is larger than the rumble noise limit ratio r_GOS, NO is determined in step S70, and NO is determined in steps S32 and S34. The advance control of the ignition timing SA and the close side correction of the TSCV 82, which are the same controls as those up to C21, are performed.

  In this manner, the ignition timing SA is advanced in the period from the engine cycle C21, the period from the engine cycle C22 to the engine cycle C23, and the period from the engine cycle C24 to the engine cycle C25 (step S31). The TSCV 82 is corrected to the closing side (step S36).

  In the engine cycle C23, when only the knocking limit ratio r_KNS exceeds 1 and the knocking intensity A_KNS exceeds the knocking limit KNSlimit in accordance with the correction (NO in steps S30 and S40 and YES in step S50), the ignition timing SA is increased. The retardation is corrected and the TSCV 82 is corrected to the closing side (step S52). On the other hand, in this example, as a result of performing the advance angle correction (step S31) of the ignition timing SA and the close side correction (step S36) of the TSCV 82 in the period from the engine cycle C24 to the engine cycle C25, The rumble noise limit ratio r_GOS exceeds 1 together with the knock limit ratio r_KNS. Therefore, in engine cycle C25, NO is determined in steps S30, S40, and S50, and YES is determined in step S60, and control in step S61 is performed. That is, the advance angle correction amount Igt is decreased, and the ignition timing SA is advanced. Since the knocking limit ratio r_KNS is larger than the rumble noise limit ratio r_GOS, NO is determined in steps S62 and S64, and the control in step S66 is performed. That is, the value of the TSCV correction amount TSCVa is decreased by the sixth correction reference amount TSCVa2, and the TSCV 82 is corrected to the closing side. The change amount TSCVa2 of TSCVa at this time is smaller than the second correction reference amount TSCVa1 that is the change amount of TSCVa in the engine cycles C21 and C23, and the TSCV82 is controlled to the close side so that the rumble noise does not deteriorate.

  As a result of the advance correction of the ignition timing SA and the close side control of the TSCV 82, in the engine cycle C26, the knocking limit ratio r_KNS is 1 or less, and the knocking intensity A_KNS is reduced to the knocking limit KNSlimit or less. However, the rumble noise is not sufficiently lowered, and the rumble noise limit ratio r_GOS is 1 or more. Therefore, in this engine cycle C26, NO is determined in step S30 and YES is determined in S40, and control in step S42 is performed. That is, the advance angle correction amount Igt is decreased to correct the ignition timing SA, and the TSCV correction amount TSCVa is increased to correct the TSCV 82 to the open side.

  In this way, in the engine cycle C27 in which the ignition timing SA is corrected by the predetermined amount and the TSCV 82 is corrected from the reference state to the predetermined amount closed side, the rumble noise limit ratio r_GOS and the knocking noise limit ratio r_KNS are both 1. When the rumble noise intensity A_GOS is greater than the rumble noise limit GOSlimit-K2 and less than or equal to GOSlimit, and the knocking noise intensity A_KNS is greater than the knocking limit KNSlimit-K1 and less than or equal to KNSlimit, the vicinity becomes 1 or less in the vicinity. In step S71, the correction of each correction amount is completed.

  As described above, in this control, it is possible to suppress the occurrence of knocking and rumble noise while balancing them, and to correct the ignition timing SA to the more advanced side while suppressing the occurrence of knocking and rumble noise. Thus, the effect that the output from the engine body 1 can be secured can be obtained.

Here, when the TSCV that only switches between fully closed and fully opened is used as the TSCV 82, the TSCV 82 may be configured to be fully opened when the TSCV final target opening θ _TSCVe exceeds a predetermined amount. . That is, after calculating the TSCV final target opening theta _TSCVe at the step S9, and fully open the TSCV82 if this TSCV final target opening theta _TSCVe is equal to or larger than the reference opening degree is set in advance, TSCV final target opening When θ _TSCVe is smaller than the reference opening, the TSCV 82 may be fully closed.

  Further, the control in steps S32 to S36 and the control in steps S62 to S66 may be omitted. That is, when the rumble noise intensity and the knocking intensity are both below the respective limit values, or when both the rumble noise intensity and the knocking intensity are above the respective limit values, the correction of the TSCV 82 may be stopped.

Further, the control of step S50 and step S52 may be omitted. For example, when the reference TSCV target opening θ _{TSCV_base} is set to 0% of fully closed, since the gas flow in the combustion chamber 17 is sufficiently strengthened, the opening of the TSCV 82 is controlled to the closed side. It does not have to be.

  Further, the method for enhancing or reducing the gas flow in the combustion chamber 17 is not limited to the above. For example, a swirl control valve that generates only swirl in the combustion chamber 17 or a tumble control valve that generates only tumble in the combustion chamber 17 may be used.

  The method for detecting knocking and rumble noise is not limited to the above. For example, knocking and rumble noise may be detected by a single vibration sensor.

  Further, the detailed structure of various actuators is not limited to the above.

1 is a schematic view of an overall structure of an engine system to which an internal combustion engine control method according to the present invention is applied. It is a schematic top view around an intake port. It is a graph which shows the waveform of the cylinder pressure with respect to a crank angle. It is a flowchart for demonstrating the calculation procedure in the control method which concerns on this invention. It is a flowchart for demonstrating the calculation procedure in the control method which concerns on this invention. It is a flowchart for demonstrating the calculation procedure in the control method which concerns on this invention. It is the figure which showed the relationship between a TSCV opening degree and MBT. It is explanatory drawing for demonstrating the relationship between a TSCV opening degree and a rumble noise. It is a figure which shows the example of a control result of the control method which concerns on this invention. It is a figure which shows the other example of a control result of the control method which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine main body 11 Cylinder 14 Crankshaft 17 Combustion chamber 80 2nd vibration sensor (2nd vibration detection means)
81 1st vibration sensor (1st vibration detection means)
82 TSCV (flow control valve)
100 Engine controller (flow control means)

Claims (10)

A control method for a spark ignition internal combustion engine,
Using vibration detection means for detecting the vibration of the internal combustion engine body,
The vibration detecting means detects the vibration intensity in the first frequency band set in advance among the vibrations of the internal combustion engine body, and the vibration intensity in the first frequency band exceeds a preset first reference intensity. A method of reducing the gas flow in the combustion chamber of the internal combustion engine by a first reference amount set in advance. A control method for an internal combustion engine according to claim 1,
A control method for an internal combustion engine, comprising a step of retarding an ignition timing for a gas in the combustion chamber when the intensity of vibration in the first frequency band exceeds the first reference intensity. A control method for an internal combustion engine according to claim 1 or 2,
The vibration detecting means detects the vibration intensity in the second frequency band set in advance higher than the first frequency band among the vibrations of the internal combustion engine body, and the vibration intensity in the second frequency band is set in advance. A method for controlling an internal combustion engine comprising a step of increasing a gas flow in a combustion chamber of the internal combustion engine by a second reference amount set in advance when the second reference strength is exceeded. A control method for an internal combustion engine according to claim 3,
A control method for an internal combustion engine, comprising a step of retarding an ignition timing for the gas in the combustion chamber when the intensity of vibration in the second frequency band exceeds the second reference intensity. A control method for an internal combustion engine according to claim 3 or 4,
When the intensity of vibration in the first frequency band exceeds the first reference intensity and the intensity of vibration in the second frequency band exceeds the second reference intensity, an ignition timing for the gas in the combustion chamber is set. A control method for an internal combustion engine comprising retarding and changing a gas flow in a combustion chamber of the internal combustion engine by an amount smaller than the first reference amount and the second reference amount. A control method for an internal combustion engine according to any one of claims 1 to 5,
Using a flow control valve provided in an intake port communicating with the combustion chamber,
A control method for an internal combustion engine, wherein the flow of gas in the combustion chamber is changed by increasing or decreasing the opening of the flow control valve. An internal combustion engine system comprising a spark ignition internal combustion engine,
Vibration detecting means for detecting vibration of the internal combustion engine body;
Flow control means for changing the gas flow in the combustion chamber of the internal combustion engine according to the intensity of vibration of the internal combustion engine body detected by the vibration detection means;
The flow control means is configured to perform combustion when the intensity of vibration in a first frequency band set in advance among vibrations of the main body of the internal combustion engine detected by the vibration detection means exceeds a first reference intensity set in advance. An internal combustion engine system characterized by reducing the gas flow in the room by a first reference amount set in advance. The internal combustion engine system according to claim 7,
The flow control means has a second reference in which a vibration intensity in a second frequency band set in advance that is higher than the first frequency band among the vibrations of the main body of the internal combustion engine detected by the vibration detection means is preset. An internal combustion engine system characterized by increasing a gas flow in the combustion chamber by a second reference amount set in advance when the strength is exceeded. The internal combustion engine system according to claim 7 or 8,
The flow control means includes a flow control valve provided in an intake port communicating with the combustion chamber and capable of changing a gas flow amount of the intake port, and the gas in the combustion chamber is changed by increasing or decreasing the opening of the flow control valve. An internal combustion engine system characterized by changing a flow. An internal combustion engine system according to claim 8 or 9,
The vibration detection means includes first vibration detection means for detecting vibrations in the first frequency band of the internal combustion engine body, and second vibration detection means for detecting vibrations in the second frequency band of the internal combustion engine body. ,
The first vibration detection means is disposed closer to the crankshaft of the internal combustion engine than the second vibration detection means, and the second vibration detection means is disposed closer to the cylinder head of the internal combustion engine than the first vibration detection means. An internal combustion engine system.

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