JP4166814B2 - Ignition timing control device for internal combustion engine - Google Patents

Description

  The present invention relates to an ignition timing control device for an internal combustion engine, and more particularly to an ignition timing control device that controls the ignition timing to the retard side in order to reduce vehicle longitudinal vibration caused by sudden torque fluctuation during acceleration.

  During acceleration of the vehicle, the drive wheels cannot follow the sudden increase in torque of the internal combustion engine, so that the drive system that transmits torque from the internal combustion engine to the drive wheels, in particular, the drive shaft is twisted, and the internal combustion engine resulting therefrom When the displacement is absorbed by the mount, acceleration fluctuations may occur and vehicle longitudinal vibration may occur. When such vehicle longitudinal vibrations occur, the feeling of acceleration is deteriorated and running stability is impaired. As a conventional ignition timing control device for solving such a problem, for example, the one disclosed in Patent Document 1 proposed by the present applicant is known.

  In this ignition timing control device, at the time of acceleration, when the rotational fluctuation amount of the internal combustion engine is larger than a predetermined amount and the differential value of the rotational fluctuation amount is smaller than a predetermined value, the ignition timing retardation is corrected. As described above, the execution timing of the ignition timing retardation correction is determined based on the rotational fluctuation amount and the rotational fluctuation differential value of the internal combustion engine because the cause of the vehicle longitudinal vibration during acceleration is the fluctuation of the vehicle driving force. This is because the rotational fluctuation amount of the internal combustion engine decreases when the vehicle driving force increases and increases when the vehicle driving force decreases, and the vehicle driving force has a phase relationship opposite to each other. . Therefore, when the rotational fluctuation amount of the internal combustion engine is larger than the predetermined amount and the rotational fluctuation amount differential value is smaller than the predetermined value, for example, when the rotational speed is increasing and the rotational fluctuation amount is decreasing, the delay is slow. By executing the ignition timing retardation correction by the angle correction amount, the torque of the internal combustion engine can be reduced at an appropriate timing when the vehicle driving force is increasing. As a result, the fluctuation of the vehicle driving force that is the cause of the acceleration fluctuation can be effectively suppressed, and the vehicle longitudinal vibration can be effectively suppressed without impairing the acceleration performance.

  The rotational fluctuation amount and the rotational fluctuation amount differential value of the internal combustion engine are calculated as follows. That is, in order to remove the influence of the installation error of the crank angle sensor, minute rotation fluctuations and noise components, the generation time interval of the crank angle signal output at every predetermined crank angle (for example, 30 degrees) from the crank angle sensor is set. The engine rotational speed NE is calculated each time a TDC signal is generated based on the respective generation time intervals. This TDC signal is output every predetermined crank angle (180 degrees in the case of four cylinders). The calculation of the rotational fluctuation amount DNE and the rotational fluctuation amount differential value DDNE is also performed for each occurrence with reference to the TDC signal, and DDNE = DNE (n) as DNE = NE (n) −NE (n−1). ) −DNE (n−1) = (NE (n) −NE (n−1)) − (NE (n−1) −NE (n−2)). The subscripts n, n−1, and n−2 represent the current value, the previous value, and the previous time value, respectively.

  However, in the above-described conventional ignition timing control device, the rotational fluctuation amount and the rotational fluctuation amount differential value of the internal combustion engine are calculated based on the TDC signal as described above. Two generations (1 TDC time) are required, and calculation of the rotational fluctuation amount differential value requires three generations (2 TDC time) of the TDC signal, which inevitably involves a time delay. The TDC time changes according to the rotation speed, and is larger as the rotation speed is lower. Accordingly, the calculation delay is also increased as the rotation speed is lower. For this reason, even if the ignition timing retardation correction is executed at the timing when the calculated rotational fluctuation amount differential value becomes smaller than the predetermined value, the execution timing of the rotational fluctuation amount differential value is actually less than the predetermined value. Since it is already delayed from the timing when it became small, the retardation correction cannot be performed at the optimal timing at which the vehicle driving force actually starts to increase, and as a result, the vehicle longitudinal vibration cannot be effectively suppressed.

  The present invention has been made to solve such a problem, and can correct the ignition timing retard at the time of acceleration at an appropriate timing in accordance with the fluctuation of the actual vehicle driving force. An object of the present invention is to provide an ignition timing control device for an internal combustion engine that can effectively suppress vehicle longitudinal vibration due to torque fluctuation while ensuring acceleration performance.

Japanese Patent Laying-Open No. 2003-65196 (FIG. 10)

  In order to achieve the above object, an invention according to claim 1 is an ignition timing control device for an internal combustion engine that controls the ignition timing to the retard side during acceleration, and an acceleration request for detecting an acceleration request to the internal combustion engine 2. Detection means (throttle opening sensor 6), rotation speed detection means (crank angle sensor 15, ECU 3) for detecting the rotation speed (engine rotation speed NE) of the internal combustion engine 2, and the internal combustion engine based on the detected rotation speed Rotational fluctuation amount calculation means (ECU 3, step 111 in FIG. 31) for calculating the rotational fluctuation amount DNE 2 and transmission ratio detection means (gear position sensor 20) for detecting the transmission gear ratio of the transmission connected to the internal combustion engine 2 The corrected rotational fluctuation amount CEA is calculated by correcting the calculated rotational fluctuation amount DNE so as to have a predetermined phase delay according to the rotational speed of the internal combustion engine 2 and the detected gear ratio. Corrected rotation fluctuation amount calculating means (ECU 3, step 31D in FIG. 30, step 114 in FIG. 31) and a delay for calculating a retard correction amount (acceleration retard correction amount IGACCR) for correcting the ignition timing IGLOG to the retard side. When the angle correction amount calculation means (ECU 3, step 60 in FIG. 4) and the acceleration request are detected, when the corrected rotation fluctuation amount CEA is larger than the third predetermined value, correction by the retardation correction amount is executed. And a retard correction execution means (ECU 3, steps 83D and 85 in FIG. 34).

  According to the ignition timing control device for an internal combustion engine, the retard correction amount calculation means calculates the retard correction amount of the ignition timing. Further, the rotational fluctuation amount is calculated based on the detected rotational speed of the internal combustion engine, and the calculated rotational fluctuation amount is determined in accordance with the rotational speed of the internal combustion engine and the detected transmission gear ratio. By correcting so as to have a phase delay of, a corrected rotation fluctuation amount is calculated. When the acceleration request is detected and the calculated corrected rotational fluctuation amount is larger than the third predetermined value, the ignition timing is corrected by the retard correction amount. The present invention is based on the following technical viewpoints.

  As described above, in the case of the TDC signal reference, 1 TDC time is required for calculating the rotational fluctuation amount, and 2 TDC time is required for calculating the rotational fluctuation amount differential value, and these calculation delays are lower as the rotational speed is lower. growing. For this reason, when the calculation delay is not compensated, the calculation timing of the rotational fluctuation amount differential value (timing at which the calculated rotational fluctuation amount differential value starts to decrease) is delayed from the optimal timing at which the vehicle driving force actually starts to increase. The delay time increases as the rotational speed decreases. On the other hand, since the rotational fluctuation amount is in a relationship that the phase is delayed by 90 degrees with respect to the rotational fluctuation amount differential value that is the differential value, the negative (−) rotational fluctuation amount is reversed, The phase is advanced 90 degrees with respect to the rotational fluctuation amount differential value. For this reason, the calculation timing of the (−) rotation fluctuation amount (timing at which the calculated (−) rotation fluctuation amount starts to decrease) is close to the optimal timing as the rotation speed is low due to the calculation delay. Below the rotational speed, the relationship is closer to the optimal timing rather than the calculation timing of the rotational fluctuation amount differential value. Further, when the transmission gear ratio changes, the natural frequency of the drive system from the internal combustion engine to the drive wheels changes, and the optimum timing changes accordingly.

  From the above viewpoint, according to the present invention, the rotational fluctuation amount is corrected so as to have a predetermined phase delay corresponding to the rotational speed and the transmission gear ratio, and the obtained corrected rotational fluctuation amount is a third predetermined value. (When the (−) rotation fluctuation amount having a predetermined phase delay is smaller than a predetermined value corresponding to the third predetermined value), the retardation correction is executed. As a result, the retardation correction can be executed at a timing close to the optimal timing at which the vehicle driving force actually starts to increase, thereby effectively suppressing vehicle longitudinal vibration due to torque fluctuations while ensuring acceleration performance. it can.

  Also, in the present invention, unlike the invention described in Patent Document 1, it is not necessary to calculate the rotational fluctuation amount differential value. Therefore, the calculation processing load can be reduced correspondingly, and the ignition timing control is simplified. Can do.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of an ignition timing control device 1 according to an embodiment of the present invention and an internal combustion engine 2 to which the ignition timing control device 1 is applied.

  The internal combustion engine (hereinafter referred to as “engine”) 2 is, for example, a four-cylinder four-cycle engine mounted on a vehicle (not shown). Further, this vehicle is an MT vehicle equipped with a manual transmission (transmission) (not shown). A throttle valve 5 is provided in the intake pipe 4 of the engine 2. The opening (hereinafter referred to as “throttle opening”) TH of the throttle valve 5 is detected by a throttle opening sensor 6 (acceleration request detecting means, throttle opening detecting means), and the detection signal is output to an ECU 3 described later. Is done.

  A fuel injection valve (hereinafter referred to as “injector”) 7 is provided for each cylinder on the downstream side of the throttle valve 5 of the intake pipe 4 and immediately upstream of the intake valve (not shown). (Illustrated). Each injector 7 is connected to a fuel pump (not shown) and electrically connected to the ECU 3, and its valve opening time (fuel injection time) TOUT is controlled by a drive signal from the ECU 3.

  Each cylinder of the engine 2 is provided with a spark plug 8 (only one is shown) and connected to the ECU 3 via a distributor 9. A high voltage is applied to each spark plug 8 at a timing corresponding to the ignition timing IGLOG by a drive signal from the ECU 3, and then the electric plug is discharged by being cut off, thereby igniting the air-fuel mixture in each cylinder. .

  On the other hand, an intake pipe absolute pressure sensor 10 is disposed downstream of the throttle valve 5 of the intake pipe 4. The intake pipe absolute pressure sensor 10 detects an intake pipe absolute pressure PBA, which is an absolute pressure in the intake pipe 4, and outputs a detection signal to the ECU 3. An intake air temperature sensor 11 is attached to the intake pipe 4 on the downstream side of the intake pipe absolute pressure sensor 10, detects the intake air temperature TA in the intake pipe 4, and outputs a detection signal to the ECU 3. Furthermore, an engine water temperature sensor 12 is attached to the main body of the engine 2, detects an engine water temperature TW that is the temperature of the cooling water circulating in the main body of the engine 2, and outputs a detection signal to the ECU 3.

  On the other hand, a cylinder discrimination sensor 13, a TDC sensor 14, and a crank angle sensor 15 (rotational speed detection means) are provided around a crankshaft (not shown) of the engine 2. These sensors 13 to 15 are configured by a magnet rotor, an MRE pickup, or the like (all not shown), generate pulse signals at respective predetermined crank angle positions, and output the pulse signals to the ECU 3. Specifically, the cylinder discrimination sensor 13 generates a cylinder discrimination signal CYL (hereinafter referred to as “CYL signal”) at a predetermined crank angle position of a specific cylinder. The TDC sensor 14 generates a TDC signal at a predetermined crank angle position slightly before TDC (top dead center) at the start of the intake stroke of each cylinder. In this example of the 4-cylinder type, one pulse of the TDC signal is output every crank angle of 180 degrees. The crank angle sensor 15 generates a crank angle signal CRK (hereinafter referred to as “CRK signal”) at a predetermined crank angle period shorter than the TDC signal (for example, every 30 degrees).

  The ECU 3 determines the crank angle position for each cylinder based on the CYL signal, the TDC signal, and the CRK signal, and calculates the rotational speed NE (hereinafter referred to as “engine rotational speed”) NE of the engine 2 based on the CRK signal. .

  A three-way catalyst 17 is disposed in the exhaust pipe 16 of the engine 2 to purify components such as HC, CO, NOx in the exhaust gas. Further, an oxygen concentration sensor 18 is provided upstream of the three-way catalyst 17 in the exhaust pipe 16 to detect the oxygen concentration in the exhaust gas and output a detection signal to the ECU 3.

  Further, in the ECU 3, a detection signal representing the vehicle speed (vehicle speed) VP from the vehicle speed sensor 19 represents a gear position number NGR corresponding to the gear position of the manual transmission from the gear position sensor 20 (transmission ratio detection means). Each detection signal is output. The gear position number NGR is assigned values 1 to 5 for the first to fifth gear positions, respectively. Further, the ECU 3 is electrically connected to an electromagnetic air conditioner clutch 21 that connects / disconnects between a compressor (not shown) of an air conditioner (hereinafter referred to as “air conditioner”) 22 and the engine 2. The connection / disconnection of the air-conditioner clutch 21 is controlled by the drive signal from.

  In this embodiment, the ECU 3 constitutes acceleration request detection means, rotation speed detection means, rotation fluctuation amount calculation means, corrected rotation fluctuation amount calculation means, retardation correction amount calculation means, and retardation correction execution means. . The ECU 3 is composed of a microcomputer including a CPU, a RAM, a ROM, an input / output interface (all not shown), and the like.

  The CPU discriminates the operating state of the engine 2 based on the engine parameter signals detected by the various sensors described above, and in accordance with the discrimination result, the fuel injection time TOUT and the ignition are synchronized with the generation of the TDC signal. The timing IGLOG is calculated, and a drive signal based on the calculation result is output to the injector 7 and the distributor 9. Further, during the acceleration of the vehicle, acceleration retard control of the ignition timing IGLOG is executed as will be described later.

  FIG. 2 is a flowchart showing a main flow of a calculation process of the ignition timing IGLOG. This process is executed in synchronization with the generation of the TDC signal. First, in step 21 (illustrated as “S21”, the same applies hereinafter), operation parameters detected by the various sensors described above are read. Next, a basic ignition timing IGMAP is determined by searching a map (not shown) according to the engine speed NE and the intake pipe absolute pressure PBA (step 22).

  Next, an acceleration retard correction amount IGACCR is calculated (step 23). The acceleration retard correction amount IGACCR is calculated in the acceleration retard control executed when the vehicle is accelerated, and details thereof will be described later.

Next, the ignition timing IGLOG is calculated by the following equation (1) using the calculated acceleration retard correction amount IGACCR (step 24).
IGLOG = IGMAP-IGACCR + IGCRO (1)
Here, IGCRO is a correction amount other than IGACR, for example, a water temperature advance angle correction amount determined according to the engine water temperature TW, an intake air temperature advance angle correction amount determined according to the intake air temperature TA, or a low temperature start The amount of advancement of warm-up for improving warm-up at the time is included.

  Then, by outputting a drive signal based on the calculated ignition timing IGLOG to the distributor 9 (step 25), the ignition timing of each cylinder is controlled, and this program ends.

  3 and 4 show the calculation process of the acceleration retard correction amount IGACCR executed in step 23 of FIG. In the following description, data stored in the ROM of the ECU 3 is distinguished from other data to be detected or updated at any time by adding “#” to the head of the data. In this process, first, in step 31, a compensation engine signal value AES is calculated. The compensation engine signal value AES is obtained by correcting the rotational fluctuation amount differential value DDNE, which is a twice differential value of the engine rotational speed NE, as described below, so as to compensate for the amplitude center deviation and calculation delay. .

  FIG. 5 shows a subroutine for calculating the compensation engine signal value AES. In this process, first, the difference (= NE (n) −NE (n−1)) between the current value NE (n) and the previous value NE (n−1) of the engine speed NE is calculated as the rotational fluctuation amount DNE. (Step 61) and the difference (= DNE (n) −DNE (n−1)) between the current value DNE (n) and the previous value DNE (n−1) of the rotational fluctuation amount is calculated as the rotational fluctuation amount differential value. Calculate as DDNE (step 62).

  Next, the table value # DDNEK / dtN is retrieved from the table shown in FIG. 6 according to the engine speed NE, and set as the amplitude center deviation compensation term DDNEK / dt (step 63). This amplitude center deviation compensation term DDNEK / dt is for compensating for the amplitude center deviation K / dt of the rotational fluctuation amount differential value DDNE due to the influence of the compression stroke fluctuation. As the engine speed NE is lower, the amplitude center shift K / dt becomes larger as the TDC time (sampling time) becomes longer. Accordingly, the table value # DDNEK / dtN corresponds to the engine speed NE. A lower value is set to a larger value. Next, a second corrected rotational fluctuation amount differential value (hereinafter referred to as “correction DDNE”) is calculated by subtracting the calculated amplitude center deviation compensation term DDNEK / dt from the rotational fluctuation amount differential value DDNE (step 64).

  Next, the table value #DDNETDCN is retrieved from the table shown in FIG. 7 according to the engine speed NE, and set as a calculated delay compensation term DDNETDC (step 65). The calculated delay compensation term DDNETDC is used to compensate for the calculated delay of the rotational fluctuation amount differential value DDNE based on the TDC signal reference. For this reason, the table value #DDNETDCN is set to be inversely proportional to the engine speed NE. ing. Next, the calculated engine compensation value DDNETDC is subtracted from the correction DDNE obtained in step 64 to calculate the compensation engine signal value AES (step 66), and this subroutine is terminated.

  Returning to FIG. 3, in step 32 following step 31, an execution region determination process for acceleration retard control is performed. This process determines whether or not the engine 2 is in an operation region suitable for executing the acceleration retard control, and is executed according to a subroutine shown in FIG. In this process, first, the table value #THACCRN is retrieved from the table shown in FIG. 9 according to the engine speed NE, and set as the throttle opening determination value THACCR (step 71). As shown in the figure, the table value #THACCRN is set to be larger as the NE value is larger than the four grid points NE1 to NE4 of the engine speed NE. It is obtained by interpolation calculation.

  The throttle opening determination value THACCR is set as described above for the following reason. As will be described later, in the acceleration retard control of the present embodiment, the throttle valve 5 is in the low opening state at the previous time is one of the conditions for starting the acceleration retard control, and the throttle opening determination is included in the determination. The value THACCR is used. On the other hand, vehicle longitudinal vibration due to acceleration fluctuations tends to occur as the engine speed NE increases, and the torque of the engine 2 tends to increase. Therefore, by expanding the throttle opening range determined to be in the low opening state. This is to increase the frequency of acceleration retard control.

  Next, the difference (TH (n) −TH (n−1)) between the current value TH (n) of the throttle opening and the previous value TH (n−1) is calculated as the throttle opening change amount DTHACR ( Step 72).

  Next, whether or not the engine water temperature TW is higher than the lower limit value #TWIGACCR (for example, 70 ° C.) (step 73), the vehicle speed VP is the lower limit value #VIGACCRL (for example, 5 km / h) and the upper limit value #VIGACCRH (for example, 180 km). / H) (step 74) and whether the engine speed NE is between the lower limit value #NIGACRRL (for example, 1000 rpm) and the upper limit value #NIGACRCH (for example, 7000 rpm) (step 74). 75).

  If any of these answers is NO, it is determined that the engine 2 is not in an operating region suitable for execution of acceleration retard control, and the acceleration retard permission flag F_IGACCR is set to “0” (step 76), and acceleration retard control is prohibited. To do. On the other hand, when all of the answers to Steps 73 to 75 are YES and the engine water temperature TW, the vehicle speed VP, and the engine speed NE are within the predetermined ranges, the engine 2 is suitable for execution of acceleration retard control. , The acceleration retard permission flag F_IGACCR is set to “1” (step 77), acceleration retard control is permitted, and this subroutine is terminated.

  Returning to FIG. 3, in steps 33 to 46 following step 32, it is determined whether or not the acceleration retard control start condition is satisfied. First, it is determined whether or not an acceleration retard permission flag F_IGACCR is “1”. If the answer is NO and the acceleration retard control is prohibited by the determination processing of FIG. 8, a rotation speed reduction flag F_ACCR, an air conditioner stop flag F_IGACCN, and an air conditioner operation flag F_IGACCAN described later are respectively set to “0” (step 34). In addition, in steps 47 and 48 in FIG. 4, an acceleration retard calculation amount IGACCRAM and an acceleration retard correction amount IGACCR, which will be described later, are respectively set to 0 and the program is terminated.

  On the other hand, when the answer to step 33 is YES and the acceleration retard control is permitted, it is determined whether or not the rotation speed reduction flag F_ACCR is “1” (step 37). As a result of execution of step 34, this answer is NO immediately after the acceleration retard control is permitted. In this case, the process proceeds to step 38 to determine whether or not the acceleration retard calculation amount IGACCRAM is zero. . As a result of execution of step 47, this answer is YES immediately after the acceleration retard control is permitted. In this case, the process proceeds to step 39 and subsequent steps.

  In this step 39, it is determined whether or not the previous value TH (n-1) of the throttle opening is smaller than the current value THACCR (n) of the throttle opening determination value set in step 71 of FIG. In Step 40, it is determined whether or not the throttle opening change amount DTHACR calculated in Step 72 of FIG. 8 is larger than the determination value #DTHACCR (for example, 10 degrees). When any of these answers is NO, that is, when the throttle valve 5 is not opened rapidly from the previous low opening state, the acceleration request is not high, and the acceleration retard control start condition is not satisfied, It is determined whether or not the acceleration retard calculation amount IGACCRAM has a value of 0 (step 41). When the answer is YES, that is, when the acceleration retard control is not being performed, the process proceeds to the step 35 and the subsequent steps, and the start of the acceleration retard control is suspended, while when the answer to step 41 is NO and the acceleration retard control is being performed, The process proceeds to the calculation process of the acceleration retard correction amount IGACCR.

  On the other hand, when both of the answers to Steps 39 and 40 are YES, it is determined whether or not the compensation engine signal value AES calculated in Step 31 is greater than 0 (Step 42). When this answer is YES, that is, when the throttle valve 5 is opened rapidly from the low opening state, the acceleration request is high, and the rotational fluctuation amount DNE increases between the previous time and the current time, the rotational speed reduction flag F_ACCR is set to “0” (step 43), and it is determined that the acceleration retard control start condition is satisfied, and the routine proceeds to step 49 and later in FIG. 4 to calculate an acceleration retard amount calculation value IGACCRAM.

  If the answer to step 42 is NO and the rotational fluctuation amount DNE has not increased, it is determined whether or not the absolute value | AES | of the compensation engine signal value is larger than a determination value # AESCCR0 (for example, 10 rpm) (step). 44). When this answer is NO, that is, even when the rotational fluctuation amount DNE is decreasing, when the decrease degree is small, step 43 is executed, and it is determined that the start condition of the acceleration retard control is satisfied. Proceed to the following.

  On the other hand, when the answer to step 44 is YES, that is, when the rotational fluctuation amount DNE is decreasing and the degree of decrease is large, the engine speed reduction flag F_ACCR is set to “1” (step 45) and acceleration is performed. Assuming that the start condition of the retard control is not satisfied, the steps 47 and 48 in FIG. 4 are executed, and the acceleration retard calculation amount IGACCRAM and the acceleration retard correction amount are set to 0 respectively. When the rotation speed reduction flag F_ACCR is set to “1” in this way, the answer to step 37 is YES, and in this case, the process proceeds to step 42 and subsequent steps. That is, when the throttle valve 5 is suddenly opened and the rotational fluctuation amount DNE is decreasing and the reduction degree is large, the start of the acceleration retard control is suspended, and then the rotational fluctuation amount DNE turns to the increasing side. After that, acceleration retard control is started.

  If the answer to step 38 is NO and acceleration retard control is being performed, it is determined whether a timer value TACCRE of a retard end timer, which will be described later, is 0 (step 46). If the answer is YES, While the process proceeds from step 39 onward, the process proceeds to step 60 when NO.

  When it is determined in step 42 or 44 that the acceleration retard control start condition is satisfied, the acceleration retard amount calculation value IGACCRAM is set in steps 49 to 59 of FIG.

  First, in steps 49 and 50, it is determined whether or not the air conditioner operation flag F_IGACCAN and the air conditioner stop flag F_IGACCN are “1”, respectively. When both of these answers are NO, it is determined whether or not the air conditioner clutch 21 (ACCL) is in the connected (ON) state (step 51). When the answer is NO, the air conditioner stop flag F_IGACCN is set to “1”. (Step 52). If YES, the air conditioner operation flag F_IGACCAN is set to "1" (step 53). If the answer to step 50 is YES and the air conditioner stop flag F_IGACCN is already set to “1”, the process proceeds to step 52 to hold the value. Similarly, the answer to step 49 is YES. When the air conditioner operation flag F_IGACCAN has already been set to “1”, the process proceeds to step 53 and the value is held. As described above, once the air conditioner stop / operation flags F_IGACCN and F_IGACCAN are set according to the disconnection / engagement state of the air conditioner clutch 21, they are held at the values thereafter.

  When the air conditioner 22 is stopped, in step 54 following step 52, the table value #IGACCRN for stopping the air conditioner is searched from the table shown in FIG. 10A according to the engine speed NE, and the acceleration retard amount Set as basic value IGACCRX. As shown in the figure, the table value #IGACCRN is set to be larger as the NE value is larger than the five grid points NE1 to NE5 of the engine speed NE. As described above, the higher the engine speed NE, the greater the torque of the engine 2 and the more likely the vehicle longitudinal vibrations occur. Therefore, the acceleration retard amount basic value IGACRRX is set to a larger value to delay the increase. This is to increase the torque reduction amount of the engine 2 by the angle correction.

  On the other hand, when the air conditioner 22 is in operation, in step 55 following step 53, the table value #IGACCRAN for operating the air conditioner is retrieved from the table shown in FIG. 10B according to the engine speed NE, and accelerated. Set as the retard amount basic value IGACRRX. As shown in the figure, the table value #IGACCRAN is larger as the NE value is larger than the five grid points NE1 to NE5 of the engine speed NE, similarly to the table value #IGACCRN when the air conditioner is stopped. In addition to being set, it is set to a value lower than the table value #IGACCRN. This is to ensure the torque of the engine 2 in response to an increase in the load of the engine 2 accompanying the operation of the air conditioner 22.

  In step 56 following step 54 or 55, the table value #KTHACRN is retrieved from the table shown in FIG. 11 according to the throttle opening TH, and set as the throttle opening correction coefficient KTHACR. As shown in the figure, the table value #KTHACRN is set to be larger as the TH value is larger than the four lattice points TH1 to TH4 of the throttle opening TH. This is because, as the throttle opening TH is larger, the torque of the engine 2 is larger and the vehicle longitudinal vibration is likely to occur. Therefore, the torque reduction amount of the engine 2 is set by setting the throttle opening correction coefficient KTHACR to a larger value. This is to make the size larger.

  Next, the routine proceeds to step 57 where the table value #KGRN is retrieved from the table shown in FIG. 12 according to the gear position number NGR and set as the gear position correction coefficient KGR. In this table, the table value #KGRN is set to a larger value as the gear position number NGR is smaller, that is, as the gear ratio is lower. This is because the lower the gear ratio, the greater the reaction from the drive wheel side during acceleration, and thus the vehicle longitudinal vibration tends to occur. Therefore, the torque of the engine 2 can be increased by setting the gear position correction coefficient KGR to a larger value. This is to further increase the amount of down.

  Next, the routine proceeds to step 58, where the value obtained by multiplying the acceleration retard amount basic value IGACRRX set at step 54 or 55 by the throttle opening correction coefficient KTHACR and the gear position correction coefficient KGR set at steps 56 and 57, respectively. The acceleration retard amount calculation value IGACCRAM is set.

  Next, at step 59, a down-count F_IGACCRD inversion timer TACCRDE and an acceleration retard end timer TACCRE for determining whether or not an acceleration retard execution flag F_IGACCRD, which will be described later, is inverted are respectively set for a predetermined time #TMACCRDE (for example, 200 ms). , #TMACCRE (for example, 1500 ms) are set and started, and an initial acceleration retard instruction flag F_IGACCR1 described later is set to “1”, an initial acceleration retard flag F_IGACCR1A and an acceleration retard execution flag F_IGACCRD are set to “0”, respectively. Set to "".

  Next, the routine proceeds to step 60, where the acceleration retard correction amount IGACCR is calculated. 13 and 14 show the subroutine. First, it is determined whether or not the rotational fluctuation amount DNE is larger than 0 (step 81). When the answer is YES and DNE> 0, that is, when the engine speed NE is increasing between the previous time and the current time, the absolute value | AES | of the compensation engine signal value is a threshold on the speed increasing side. It is determined whether or not the value is greater than or equal to the value #AESACCRP (for example, 10 rpm) (step 82). If the answer is NO and | AES | <#AESACCRP, the process proceeds to step 95 and later. This determination is for eliminating the influence of the noise component included in the compensation engine signal value AES due to the combustion fluctuation of the engine 2 and preventing the malfunction of the acceleration retard due to the noise component.

  If the answer to step 82 is YES and | AES | ≧ # AESACCRP, it is determined whether or not the compensation engine signal value AES is equal to or greater than 0 (step 83). If the answer is YES and AES ≧ 0, that is, if the rotational fluctuation amount DNE is not decreasing, it is determined that the acceleration retard execution condition is not satisfied, and the routine proceeds to step 95. On the other hand, when the answer to step 83 is NO and AES <0, that is, between the previous time and the current time, when the engine speed NE increases and the rotational fluctuation amount DNE decreases, the vehicle driving force It is determined that the acceleration retard execution flag F_IGACCRD is “1” (step 84). When the answer is NO, the acceleration retard execution flag F_IGACCRD is set to “1” (step 85), while when the answer is YES and acceleration retard is already being executed, the process proceeds to step 95.

  Next, it is determined whether or not an initial acceleration retard instruction flag F_IGACCR1 is “1” (step 86). As a result of the execution of step 59 in FIG. 4, the answer is YES immediately after the acceleration retard control is started. In this case, the process proceeds to step 87 and the initial acceleration retard flag F_IGACCR1A is set to “1”. Thereafter, the F_IGACCRD inversion timer TACCRDE is set for a predetermined time #TMACCRDE and started (step 88). On the other hand, when the answer to step 86 is NO and F_IGACCR1 = 0, that is, not immediately after the start of the acceleration retard control, step 87 is skipped and the process proceeds to step 88.

  On the other hand, when the answer to step 81 is NO and the rotational fluctuation amount DNE ≦ 0, that is, when the engine speed NE is decreasing or has not changed, the absolute value | AES | of the compensation engine signal value decreases. It is determined whether or not the threshold value is greater than or equal to the threshold value #AESACCRM (for example, 5 rpm) (step 89). If the answer is NO and | AES | <#AESACCRM, the process proceeds to step 95. If the answer to step 89 is YES and | AES | ≧ # AESACCRM, it is determined whether or not the compensation engine signal value AES is equal to or greater than 0 (step 90). If the answer is NO and AES <0, that is, if the rotational fluctuation amount DNE is decreasing, the routine proceeds to step 95.

  On the other hand, if the answer to step 90 is YES and AES ≧ 0, that is, if the engine speed NE is decreasing and the rotational fluctuation amount DNE is not decreasing, the vehicle driving force is not increasing and acceleration is performed. Assuming that the retard stop condition is satisfied, it is determined whether or not the acceleration retard execution flag F_IGACCRD is “1” (step 91). If the answer is YES and the acceleration retard is being executed, the acceleration retard execution flag F_IGACCRD is set to “0” (step 92), while if the answer is NO and the acceleration retard is already stopped. The process proceeds to step 95.

  Next, it is determined whether or not the initial acceleration retard flag F_IGACCR1A is “1” (step 93). When the answer is YES, that is, when the initial acceleration retard is being executed, the initial acceleration retard instruction flag F_IGACCR1 and the initial acceleration retard flag F_IGACCR1A are both set to “0” (step 94), and then the process proceeds to step 88. The F_IGACCRD inversion timer TACCRDE is started. If the answer to step 93 is NO and acceleration retard other than the first time is being executed, step 94 is skipped and the process proceeds to step 88.

  As described above, the engine speed NE increases (DNE> 0) and the compensation engine signal value AES decreases (AES <0, | AES | ≧) between the previous time and the current time. #AESACCRP), the vehicle driving force is increased, and the acceleration retard is executed on the assumption that the acceleration retard execution condition is satisfied. On the other hand, when the engine speed NE has not increased (DNE ≦ 0) and the rotational fluctuation amount DNE has not decreased (AES ≧ 0, | AES | ≧ # AESACCRM), the vehicle driving force has not increased. However, the acceleration retard is stopped on the assumption that the acceleration retard stop condition is satisfied. When neither of the above two conditions is satisfied, the previous control state is maintained.

  Next, in step 95 of FIG. 11 following step 88 and the like, it is determined whether or not the throttle opening TH is smaller than the throttle opening determination value THACCR set in step 71 of FIG. If the answer is NO and the throttle opening TH is not in the low opening state, it is determined whether or not the timer values of the F_IGACCRD inversion timer TACCRDE and the acceleration retard end timer TACCRE are 0 (steps 96 and 97). When the answer to both steps 96 and 97 is NO, it is determined whether or not the acceleration retard execution flag F_IGACCRD is “1” (step 98).

  If the answer to step 98 is YES and the acceleration retard execution condition is satisfied, it is determined whether or not the initial acceleration retard flag F_IGACCR1A is “1” (step 99). If this answer is YES, that is, this time is the first acceleration retard after the start of the acceleration retard control, the first time correction coefficient larger than the value 1.0 is added to the acceleration retard amount calculated value IGACCRAM set in step 58 of FIG. A value obtained by multiplying # KIGACCR1 (for example, 1.5) is set as the acceleration retard correction amount IGACR (step 100). If the answer to step 99 is NO, that is, if the current acceleration retard is the second or later, the acceleration retard amount calculation value IGACCRAM is set as it is as the acceleration retard correction amount IGACCR (step 101). On the other hand, if the answer to step 98 is NO and F_IGACCRD = 0, that is, if the acceleration retard stop condition is satisfied, the acceleration retard correction amount IGACR is set to 0 (step 102), and this subroutine is terminated. To do.

  As described above, in this acceleration retard control, when the acceleration retard execution flag F_IGACCRD = 1, that is, when the engine speed NE increases and the rotational fluctuation amount DNE decreases, execution of acceleration retard and F_IGACCRD = 0 In other words, the stop of the acceleration retard when the engine speed NE is decreasing and the rotational fluctuation amount DNE is not decreasing is alternately performed while switching. Also, the acceleration retard correction amount IGACRCR is set to a larger value by applying the initial correction coefficient # KIGACRCR1 only during the first acceleration retard.

  On the other hand, when the answer to step 97 is YES and the timer value of the acceleration retard end timer TACCRE = 0, that is, when the predetermined time #TMMACCRE has elapsed after the start of the acceleration retard control, the mode shifts to the acceleration retard control end mode. Then, a value obtained by subtracting the retard return amount #DIGACR (for example, 0.2 degrees) from the acceleration retard amount calculated value IGACCRAM is set as a new IGACCRAM value (step 103). After the acceleration retard end timer TACCRE reaches the value 0 in this way, the answer to step 46 in FIG. 3 is YES, so that the process proceeds to step 39 and subsequent steps. Therefore, unless the throttle valve 5 is suddenly opened, step 41 Step 103 is repeatedly executed until the answer to NO is NO, that is, until the acceleration retard amount calculated value IGACCRAM becomes zero. As a result, the acceleration retard correction amount IGACR is gradually decreased, and the acceleration retard control is terminated when the value becomes zero.

  When the answer to step 96 is YES and the timer value of the F_IGACCRD inversion timer TACCRDE = 0, that is, when the acceleration retard execution flag F_IGACCRD is not inverted for a predetermined time #TMACCRDE, the vehicle longitudinal vibration has converged. As a result, the acceleration retard control is to be terminated, the timer value of the acceleration retard termination timer TACCRE is reset to 0 (step 104), and then the process proceeds to step 103. As a result, the acceleration retard control is forcibly shifted to the end mode, and the acceleration retard correction amount IGACCR is gradually reduced.

  Further, when the answer to step 95 is YES and TH <THACCR, it is determined whether or not the throttle opening change amount DTHACR is smaller than the value 0 and the absolute value | DTHACR | is larger than the determination value #DTHACR. (Step 105). When the answer is NO, the process proceeds to step 96, while when YES, that is, when the throttle valve 5 is suddenly closed, the process proceeds to step 104, and the timer value of the acceleration retard end timer TACCRE is reset to zero. The acceleration retard control is forcibly shifted to the end mode.

  As described above, in the acceleration retard control, when the predetermined time #TMMACCRE has elapsed from the start thereof, when the acceleration retard execution flag F_IGACCRD is not reversed for the predetermined time #TMACCRDE, or when the throttle valve 5 is suddenly closed. In some cases, the process ends through an end mode in which the acceleration retard correction amount IGACR is gradually decreased. Further, during execution of this end mode and after the end of execution, the answer to Steps 46 and 38 in FIG. 3 is YES, respectively, so that the process proceeds to Step 39 and the subsequent steps. In this state, the throttle valve 5 is rapidly opened again. When the execution condition is satisfied, the acceleration retard control is resumed.

  FIG. 15 shows an operation example based on the acceleration retard control described so far. That is, when the throttle valve 5 is suddenly opened, the engine speed NE increases and the compensation engine signal value AES starts to increase (step 42: YES in FIG. 3), and acceleration retard control is started (time t1). 4), the acceleration retard amount calculation value IGACCRAM is calculated, the F_IGACCRD inversion timer TACCRDE and the acceleration retard end timer TACCRE are started, and the initial acceleration retard instruction flag F_IGACCR1 is set to “1”. Set.

  Thereafter, when the rotational fluctuation amount DNE> 0, the compensation engine signal value AES <0, and | AES | ≧ # AESACCRP is satisfied, that is, the engine rotational speed NE has increased, and the rotational fluctuation amount DNE has started to decrease. At time (time t2), the acceleration retard execution flag F_IGACCRD is set to “1” (step 84 in FIG. 13), and the acceleration retard is executed accordingly. That is, the acceleration retard correction amount IGACCR is set to the acceleration retard amount calculated value IGACCRAM (step 101 in FIG. 14), and the acceleration retard correction amount IGACCR is subtracted from the basic ignition timing IGMAP or the like (IGMAP + IGCRO) according to the equation (1). This value is set as the ignition timing IGLOG. In addition, only at the time of the first acceleration retard, according to the fact that the flag F_IGACCR1A during the initial acceleration retard is set to “1”, the acceleration retard correction amount IGACR is set to the acceleration retard amount calculated value IGACCRAM by the initial correction coefficient # KIGACRCR1. The multiplied value is set (step 100).

  Thereafter, when DNE ≦ 0, AES ≧ 0, and | AES | ≧ # AESACCRM is satisfied, that is, when the engine speed NE has not increased and the rotational fluctuation amount DNE starts to increase (time t3). In addition, the acceleration retard execution flag F_IGACCRD is set to “0” (step 92 in FIG. 13), and the acceleration retard correction amount IGACR is set to 0 (step 102 in FIG. 14) accordingly, so that the acceleration retard is reduced. Stopped.

  Thereafter, every time the acceleration retard execution flag F_IGACCRD is switched between “1” and “0” according to changes in the rotational fluctuation amount DNE and the compensation engine signal value AES (time t4 to t7), the acceleration retard is executed and stopped. Are performed alternately.

  When the acceleration fluctuation G is gradually reduced by the acceleration retard control as described above and the vehicle longitudinal vibration converges, the acceleration retard execution flag F_IGACCRD is not reversed for a predetermined time #TMACCRDE. The TACCRDE timer value becomes 0 (time t8), and the acceleration retard end timer TACCRE is forcibly reset to 0 (step 104) accordingly, thereby shifting to the end mode. In this end mode, unless the throttle valve 5 is rapidly opened, the retard return amount #DIGACRCR is repeatedly subtracted from the acceleration retard amount calculated value IGACCRAM (step 103), so that the acceleration retard correction amount IGACCR is It is gradually reduced until the value becomes zero. In the middle of the acceleration retard control, when the operating range of the engine 2 deviates from the execution range, the acceleration retard correction amount IGACR is set to 0 (step 48 in FIG. 4), and the acceleration retard control is immediately terminated. Is done. FIG. 15 shows an example in which such deviation from the execution region of the engine 2 occurs in the middle of the end mode (time t9).

  As described above, according to the present embodiment, when the throttle valve 5 is suddenly opened, when the rotational fluctuation amount DNE> 0 of the engine 2 and the compensation engine signal value AES <0 is satisfied, that is, the engine speed When the number NE is increasing and the rotational fluctuation amount DNE starts to decrease, the acceleration retard with the acceleration retard correction amount IGACCR is executed. The compensation engine signal value AES is a value obtained by correcting the rotational fluctuation amount differential value DDNE so as to compensate for the calculation center delay due to the calculation of the amplitude center deviation due to the influence of the compression stroke fluctuation and the TDC signal. Therefore, the acceleration retard can be executed at the optimal timing when the vehicle driving force actually increases, thereby reducing the torque of the internal combustion engine optimally, and as a result, the vehicle longitudinal vibration is most effectively suppressed. Can do.

  FIG. 16 shows the results of a test performed to confirm the above-described vehicle longitudinal vibration suppression effect by the acceleration retard control of the present embodiment. (A) is an example according to the present embodiment, and (b) is a parameter for determining the execution timing of acceleration retard, instead of the compensation engine signal value AES of the present embodiment, the rotational fluctuation amount differential value DDNE. Comparative examples when used are shown. As is clear from the comparison between the two figures, in the comparative example, both the fluctuation of the engine speed NE and the amplitude of the vehicle longitudinal vibration are large, and the vehicle longitudinal vibration is not sufficiently suppressed, whereas in the embodiment, the acceleration is accelerated. As a result of optimally determining the execution timing of the retard based on the compensation engine signal value AES, it has been confirmed that the fluctuation of the engine speed NE and the amplitude of the vehicle longitudinal vibration are both small and the vehicle longitudinal vibration can be sufficiently suppressed.

  In this embodiment, since the acceleration retard is executed on the condition that the absolute value of the compensation engine signal value AES is equal to or greater than the threshold value #AESACCRP, the influence of noise components on the compensation engine signal value AES is eliminated. Therefore, the malfunction and hunting of the acceleration retard due to noise can be appropriately avoided.

  Further, when DNE ≦ 0 and AES ≧ 0 is satisfied, that is, when the engine speed NE has not increased and the rotational fluctuation amount DNE starts to increase, the acceleration retard is stopped, so that the vehicle drive Unnecessary torque reduction of the engine 2 in a state where the force is reduced can be avoided, and higher acceleration performance can be obtained. Also in this case, since the acceleration retard is stopped on condition that the absolute value of the compensation engine signal value AES is equal to or greater than the threshold value #AESACCRM, the influence of the noise component on the compensation engine signal value AES can be eliminated. Thus, erroneous stop and hunting of the acceleration retard due to this can be appropriately avoided. Moreover, since the advance angle correction is not performed only by stopping the acceleration retard, the occurrence of knocking can be reliably prevented.

  Further, since the acceleration retard correction amount IGACR is set according to the engine speed NE and the gear ratio of the transmission, and further, the throttle opening TH and the operating state of the air conditioner 22, the torque reduction amount of the engine 2 due to the acceleration retard is Appropriate control can be performed according to the degree of acceleration fluctuation, and as a result, fluctuations in vehicle driving force and vehicle longitudinal vibration resulting therefrom can be better suppressed. Further, the torque of the engine 2 can be appropriately ensured in response to an increase in load accompanying the operation of the air conditioner 22.

  Furthermore, at the time of the first acceleration retard, the acceleration retard correction amount IGACR is set to a larger value by the initial correction coefficient # KICGCR1, so that the torque reduction can be strengthened especially at the start of acceleration, thereby reducing the longitudinal vibration of the vehicle. Convergence can be improved.

  Next, the acceleration retard control according to the second embodiment of the present invention will be described with reference to FIGS. In addition, since this embodiment and the embodiment to be described later differ from the first embodiment only in the execution contents of some steps of the acceleration retard control, in the following, the steps having the same execution contents are common. Step numbers will be assigned, and the description will focus on steps with different execution contents.

  FIG. 17 shows the first half of the calculation process of the acceleration retard correction amount IGACCR corresponding to FIG. 3 of the first embodiment, and the latter half of the same processing content as FIG. 4 is omitted. As apparent from the comparison with FIG. 3, the calculation process of this embodiment differs from the first embodiment only in the execution contents of steps 42A and 44A corresponding to the steps 42 and 44, and the acceleration retard As one of the parameters for determining whether the control start condition is satisfied, the rotational fluctuation amount DNE is used instead of the compensation engine signal value AES of the first embodiment. Specifically, when the throttle valve 5 is suddenly opened (steps 39 and 40: YES) or the like, in step 42A, it is determined whether or not the rotational fluctuation amount DNE is greater than 0, and the answer is If YES, it is determined that the acceleration retard control start condition is satisfied, because the acceleration request is high and the engine speed NE is increasing. If the answer to step 42A is NO, it is determined in step 44A whether or not the absolute value | DNE | of the rotational fluctuation amount is larger than a determination value # DNECR0 (for example, 10 rpm). If the answer is YES, Assuming that the engine speed NE has decreased by a large decrease amount, it is determined that the acceleration retard control start condition is not satisfied.

  FIG. 18 shows the first half of the subroutine for calculating the acceleration retard correction amount IGACCR corresponding to FIG. 13 of the first embodiment, and the latter half of the same processing contents as in FIG. 14 is omitted. As is clear from the comparison with FIG. 13, the calculation processing of this embodiment is different from the first embodiment only in the execution contents of steps 82A and 89A corresponding to the steps 82 and 89. Specifically, when the rotational fluctuation amount DNE> 0 (step 81: YES) and the engine speed NE is increasing, in step 82A, the absolute value | DNE | of the rotational fluctuation amount is a threshold on the rotational increase side. It is determined whether or not the value is greater than or equal to the value #DNEACCRP (for example, 10 rpm). If the answer is NO and | DNE | <#DNEACCRP, it is determined that the acceleration retard execution condition is not satisfied. Further, when the rotational fluctuation amount DNE ≦ 0 (step 81: NO) and the engine speed NE is not increasing, in step 89A, the absolute value | DNE | of the rotational fluctuation amount is the threshold value #DNEACCRM on the rotation reduction side. It is determined whether or not (for example, 5 rpm) or more. If the answer is NO and | DNE | <#DNEACCRM, it is determined that the acceleration retard stop condition is not satisfied.

  FIG. 19 shows an operation example of acceleration retard control according to the present embodiment. That is, when the throttle valve 5 is opened rapidly, the engine speed NE increases, and when the rotational fluctuation amount> 0 is established (step 42A: YES), the acceleration retard control is started (time t1). Thereafter, when DNE> 0, | DNE | ≧ # DNEACCRP, and when the compensation engine signal value AES <0 is satisfied (step 82A: YES), that is, the engine speed NE has increased and the rotational fluctuation amount DNE has decreased. Acceleration retard is executed (time t2). Thereafter, when DNE ≦ 0, | DNE | ≧ # DNEACCRM, and AES ≧ 0 is satisfied (step 89A: YES), that is, the engine speed NE has not increased and the rotational fluctuation amount DNE has increased. When starting to start, the acceleration retard is stopped (time t3).

  As described above, according to the present embodiment, when the throttle valve 5 is suddenly opened, the compensation engine signal value AES that compensates for the rotational fluctuation amount DNE, the amplitude center deviation of the rotational fluctuation amount differential value DDNE, and the calculation delay. Based on the above, acceleration retard is executed when DNE> 0 and AES <0, that is, when the engine speed NE is increasing and the rotational fluctuation amount DNE starts to decrease. Therefore, as in the first embodiment, acceleration retard can be executed at the optimal timing when the vehicle driving force actually increases, and the vehicle longitudinal vibration can be most effectively suppressed. Further, when DNE ≦ 0 and AES ≧ 0 is satisfied, that is, when the engine speed NE has not increased and the rotational fluctuation amount DNE starts to increase, the acceleration retard is stopped, so that the first Similar to the embodiment, unnecessary torque reduction of the engine 2 in a state where the vehicle driving force is reduced can be avoided, and higher acceleration performance can be obtained. Further, since the acceleration retard is executed and stopped on condition that the absolute value of the rotational fluctuation amount DNE is equal to or greater than the threshold value #DNEACCRP or #DNEACCRM, the influence of noise components on the rotational fluctuation amount DNE is eliminated. The same effects as those of the first embodiment can be obtained, for example, malfunction of acceleration retard and hunting can be appropriately avoided.

  Next, the acceleration retard control according to the third embodiment of the present invention will be described with reference to FIGS. FIG. 20 shows the first half of the calculation process of the acceleration retard correction amount IGACR corresponding to FIG. 3 of the first embodiment and FIG. 17 of the second embodiment, and the latter half of the same processing content as FIG. 4 is omitted. Has been. As apparent from the comparison with FIG. 17, the calculation process of the present embodiment is different from the second embodiment only in the execution contents of step 31B corresponding to step 31. That is, in this step 31B, corrected DDNE is calculated instead of the compensation engine signal inter-AES of the first and second embodiments. FIG. 21 shows the calculation subroutine. In Steps 61B to 64B, exactly the same as Steps 61 to 64 in FIG. 5, based on the detected engine speed NE, the rotational fluctuation amount DNE, the rotational fluctuation amount differentiation. The value DDNE, the amplitude center shift compensation term DDNEK / dt, and the correction DDNE are sequentially calculated. That is, in the correction DDNE calculation process, the calculation of the compensation engine signal value AES is omitted, and only the amplitude center shift K / dt due to the compression stroke fluctuation is compensated for the rotational fluctuation amount differential value DDNE.

  FIG. 22 shows the first half of an acceleration retard correction amount IGACR calculation subroutine corresponding to FIG. 13 of the first embodiment and FIG. 18 of the second embodiment, and omits the latter half of the same processing contents as FIG. Has been. In this calculation process, first, it is determined whether or not the engine speed NE is equal to or higher than a predetermined engine speed #NETRG (for example, 2000 rpm) (step 81B). If the answer is YES and NE ≧ # NETRG, it is determined whether or not the correction DDNE calculated in step 31B is smaller than 0 (step 83B). When the answer is YES and correction DDNE <0, it is determined that the acceleration retard execution condition is satisfied, and the process proceeds to steps 84 to 88 as in the first embodiment, and the acceleration retard is executed. On the other hand, if the answer to step 83B is NO and the correction DDNE ≧ 0, it is determined that the acceleration retard execution condition is not satisfied, and the process proceeds to steps 91 to 94 as in the first embodiment, and the acceleration retard is stopped. .

  On the other hand, when the answer to step 81B is NO and NE <#NETRG, it is determined whether or not the rotational fluctuation amount DNE is greater than 0 (step 83BB). When the answer is YES and DNE> 0, it is determined that the acceleration retard execution condition is satisfied, and the same steps 84B to 88B as the steps 84 to 88 are executed, and the acceleration retard is executed. On the other hand, when the answer to step 83BB is NO and DNE ≦ 0, it is determined that the acceleration retard execution condition is not satisfied, and steps 91B to 94B similar to steps 91 to 94 are executed, and the acceleration retard is stopped. .

  As described above, in this embodiment, when the engine speed NE is equal to or higher than the predetermined speed #NETRG, based on the correction DDNE, and when the engine speed NE is less than the predetermined speed #NETRG, based on the rotational fluctuation amount DNE. Thus, execution and stop of the acceleration retard are determined. This is due to the following reason. As described above, 1 TDC time is required for calculating the rotational fluctuation amount DNE, and 2 TDC time is required for calculating the rotational fluctuation amount differential value DDNE, and the calculation delay increases as the rotational speed decreases. Therefore, when the calculation delay is not compensated, the calculation timing of the rotational fluctuation amount differential value DDNE (the timing at which the calculated rotational fluctuation amount differential value DDNE starts to decrease) is as shown in FIG. The optimum timing which starts increasing is delayed, and the delay time is larger as the engine speed NE is lower.

  On the other hand, the rotational fluctuation amount DNE has a relationship that the phase is delayed by 90 degrees with respect to the rotational fluctuation amount differential value DDNE that is a differential value thereof, and therefore, the negative (−) rotational fluctuation amount (hereinafter referred to as “−”). "-DNE") has a relationship that the phase is advanced by 90 degrees with respect to the rotational fluctuation amount differential value DDNE. As shown in the figure, the advance time of the -DNE calculation timing (the calculated -DNE starts to decrease) has a low engine speed NE due to a calculation delay corresponding to the TDC time of the rotational fluctuation amount DNE. As a result, the calculation timing of -DNE coincides with the optimum timing when the engine speed NE is # NE0, and is later than the optimum timing when it is less than # NE0. Dotted lines LR and LA in the figure represent an allowable delay time and an allowable advance time corresponding to a limit value that does not affect the controllability of the acceleration retard.

  FIG. 24 shows the delay time of the calculation timing of the rotational fluctuation amount differential value DDNE and the advance time or delay time of the calculation timing of -DNE as the “deviation time” of the calculation timing, and are drawn in common. is there. As can be seen from the figure, when the engine speed NE is the predetermined engine speed #NETRG, the time difference between the two calculation timings is equal, and when NE> #NETRG, the calculation timing of the rotational variation differential value DDNE is determined by the optimal timing When NE <#NETRG, the calculation timing of -DNE is closer to the optimum timing.

  Based on this relationship, in the present embodiment, as described above, when the engine speed NE is less than the predetermined engine speed #NETRG, when the rotational fluctuation amount DNE is larger than the value 0 (closer to the optimum timing). When the engine speed NE is equal to or higher than the predetermined engine speed #NETRG when the DNE is smaller than the value 0), the rotational fluctuation amount DNE decreases when the correction DDNE closer to the optimal timing is smaller than the value 0. Acceleration retard is executed on the assumption that the vehicle driving force is increasing.

  FIG. 25 and FIG. 26 show an example of the acceleration retard control operation according to the present embodiment in the case where the engine 2 is in the high rotation range (NE ≧ # NETRG) and the low rotation range (NE <#NETRG), respectively. . When the engine 2 is in the high speed range, the rotational fluctuation amount DNE is obtained when the correction DDNE <0 is satisfied after the engine speed NE increases with the rapid opening of the throttle valve 5 (step 83B: YES). Is reduced (time t2). Thereafter, when the correction DDNE ≧ 0 (step 83B: NO), the acceleration retard is stopped (time t3), assuming that the rotational fluctuation amount DNE has increased. On the other hand, as shown in FIG. 26, when the engine 2 is in the low speed range, after the engine speed NE increases with the rapid opening of the throttle valve 5, the rotational fluctuation amount DNE> 0 is established ( In step 83BB: YES), acceleration retard is executed (time t2), assuming that the rotational fluctuation amount DNE is decreasing. Further, after that, when the rotational fluctuation amount ≦ 0 (step 83BB: NO), it is determined that the rotational fluctuation amount DNE has increased, and the acceleration retard is stopped (time t3).

  As described above, according to the present embodiment, among the correction DDNE and the rotational fluctuation amount DNE, the acceleration retard execution timing is determined by using the smaller calculation timing deviation with respect to the optimal timing according to the engine speed NE. Therefore, the acceleration retard can be executed within the allowable deviation time L (see FIG. 24) without causing a large timing deviation, and the effect of suppressing the vehicle longitudinal vibration can be obtained without any trouble. Moreover, the effect which compensated the amplitude center shift | offset | difference can be maintained by employ | adopting correction | amendment DDNE as a parameter showing a rotation fluctuation amount differential value. Furthermore, by adopting the correction DDNE, the calculation processing load can be reduced compared with the first and second embodiments using the corrected engine signal value AES compensated for the calculation delay, thereby simplifying the ignition timing control. Can be planned.

  Next, the acceleration retard control according to the fourth embodiment of the present invention will be described with reference to FIGS. FIG. 27 shows the first half of an acceleration retard correction amount IGACCR calculation subroutine corresponding to FIG. 22 of the third embodiment. As apparent from the comparison with FIG. 22, the calculation process of this embodiment is different from the third embodiment in that the absolute value | DNE | is discriminated in order to eliminate the influence of the noise component on the rotational fluctuation amount DNE. Only the process (steps 82C, 89C, 82CC and 89CC) is added. Specifically, when engine rotational speed NE ≧ predetermined rotational speed #NETRG and correction DDNE <0 (step 81B: YES), in step 82C, the absolute value | DNE | It is determined whether or not the value is greater than or equal to the value #DNEACCRP (for example, 10 rpm). When this answer is NO and | DNE | <#DNEACCRP, it is determined that the acceleration retard execution condition is not satisfied. On the other hand, when correction DDNE ≧ 0 (step 81B: NO), in step 89C, it is determined whether or not the absolute value | DNE | of the rotational fluctuation amount is equal to or greater than a threshold value #DNEACCRM (for example, 5 rpm) on the rotation decrease side. To do. If the answer is NO and | DNE | <#DNEACCRM, it is determined that the acceleration retard stop condition is not satisfied. When engine speed NE <predetermined speed #NETRG and rotational fluctuation amount DNE> 0 (step 81B: YES), or when DNE ≦ 0, the same determination is made at step 89C or step 89CC.

  FIG. 28 and FIG. 29 show operation examples of the acceleration retard control according to the present embodiment, respectively, in the case where the engine 2 is in a high rotation range (NE ≧ # NETRG) and a low rotation range (NE <#NETRG). . When the engine 2 is in the high speed range, the engine speed NE increases with the rapid opening of the throttle valve 5, and then the correction DDNE <0 and the absolute value of the rotational fluctuation | DNE | ≧ # DNEACCRP When established (step 82C: YES), acceleration retard is executed (time t2). Further, after that, when correction DDNE ≧ 0 and | DNE | ≧ # DNEACCRM is established (step 89C: YES), the acceleration retard is stopped (time t3). On the other hand, as shown in FIG. 29, when the engine 2 is in the low speed range, after the engine speed NE increases with the rapid opening of the throttle valve 5, the rotational fluctuation amount DNE> 0 and | DNE When | ≧ # DNEACCRP is satisfied (step 82CC: YES), acceleration retard is executed (time t2). Thereafter, when DNE ≦ 0 and | DNE | ≧ # DNEACCRM is established (step 89CC: YES), the acceleration retard is stopped (time t3).

  As described above, the present embodiment is obtained by adding the determination processing of the absolute value | DNE | of the rotation fluctuation amount as described above to the third embodiment. As well as the influence of the noise component on the rotational fluctuation amount DNE can be eliminated, and malfunction of acceleration retard and hunting can be appropriately avoided.

  Next, acceleration retard control according to the fifth embodiment of the present invention will be described with reference to FIGS. FIG. 30 shows the first half of the calculation process of the acceleration retard correction amount IGACCR corresponding to FIG. 3 of the first embodiment, and the latter half of the same processing content as FIG. 4 is omitted. As is clear from the comparison with FIG. 3, the calculation processing of this embodiment differs from the first embodiment only in the execution contents of steps 31D, 42D and 44D corresponding to the steps 31, 42 and 44. As a parameter representing the rotational fluctuation, the corrected rotational fluctuation amount CEA is used instead of the compensation engine signal value AES of the first embodiment. The corrected rotational fluctuation amount CEA is obtained by correcting the rotational fluctuation amount DNE so as to have a phase lag according to the engine speed NE and the gear ratio (transmission ratio) of the transmission.

  In step 31D, the corrected rotational fluctuation amount CEA is calculated. FIG. 31 shows the calculation subroutine. First, the rotational fluctuation amount DNE is calculated based on the engine speed NE (step 111). Next, the table value #DNETDCN is retrieved from the table shown in FIG. 32 according to the engine speed NE, and is set as the TDC correction term DNETDC (step 112). This TDC correction term DNETDC is for delaying the phase of the rotational fluctuation amount DNE by the advance time of -DNE with respect to the optimum timing. Therefore, this table value #DNETDCN is basically the same as the -DNE curve of FIG. 23, and is set to a larger value as the engine speed NE is higher.

  Next, the table value #DNEGEARN is retrieved from the table shown in FIG. 33 in accordance with the gear position of the transmission, and set as a gear position correction term DNEGEAR (step 113). This gear position correction term DNETDC is for delaying the phase of the rotational fluctuation amount DNE by this change amount, because the optimum timing changes as the natural frequency of the drive system changes according to the gear ratio. . In this example, the table value #DNEGEARN is set to a larger value as the transmission gear ratio is higher. Next, a corrected rotational fluctuation amount CEA is calculated by subtracting the calculated TDC correction term DNETDC and gear position correction term DNEGEAR from the rotational fluctuation amount DNE (step 114), and this subroutine is terminated.

  Further, in step 42D of FIG. 30, it is determined whether or not the calculated corrected rotational fluctuation amount CEA is larger than the value 0. If the answer is YES, the acceleration request is high and the engine speed NE is increasing. It is determined that the acceleration retard control start condition is satisfied. If the answer to step 42D is NO, it is determined in step 44D whether or not the absolute value | CEA | of the corrected rotation fluctuation amount is greater than a determination value # CEACCR0 (for example, 10 rpm). In some cases, it is determined that the acceleration retard control start condition is not satisfied, assuming that the engine speed NE has decreased by a large decrease amount.

  FIG. 34 shows the first half of the subroutine for calculating the acceleration retard correction amount IGACCR corresponding to FIG. 13 of the first embodiment, and the latter half of the same processing contents as in FIG. 14 is omitted. As is clear from the comparison with FIG. 13, the calculation processing of this embodiment is executed in the steps 82D, 83D, 89D, and 90D corresponding to the steps 82, 83, 89, and 90 in comparison with the first embodiment. Only is different. Specifically, when the rotational variation amount DNE> 0 (step 81: YES) and the engine rotational speed NE is increasing, the absolute value | CEA | of the corrected rotational variation amount is the threshold value # on the rotational increase side. It is determined whether or not it is greater than or equal to CEAACCRP (for example, 10 rpm) (step 82D), and it is determined whether or not the corrected rotational fluctuation amount CEA is larger than a value 0 (third predetermined value) (step 83D). If both of these answers are YES, | CEA | ≧ # CEAACCRP, and CEA> 0, it is determined that the acceleration retard execution condition is satisfied, while if any of these answers is NO, the acceleration is performed. It is determined that the retard execution condition is not satisfied.

  Further, when the rotational fluctuation amount DNE ≦ 0 (step 81: NO) and the engine rotational speed NE is not increasing, the absolute value | CEA | of the corrected rotational fluctuation amount is a threshold value #CEAACCRM (for example, 5 rpm) on the rotation reduction side It is determined whether or not (step 89D) and whether the corrected rotational fluctuation amount CEA is smaller than 0 (step 90D). If both of these answers are YES, | CEA | ≧ # CEAACCRM, and CEA <0, it is determined that the acceleration retard stop condition is satisfied, while if any of these answers is NO, the acceleration is It is determined that the retard stop condition is not satisfied.

  FIG. 35 shows an operation example of the acceleration retard control according to the present embodiment. That is, when the throttle valve 5 is opened rapidly, the engine speed NE increases, and when the corrected rotational fluctuation amount CEA> 0 is established (step 42D: YES), the acceleration retard control is started (time t1). Thereafter, when the rotational fluctuation amount DNE> 0, | CEA | ≧ # CEAACCRP and CEA> 0 is satisfied (step 83D: YES), that is, the engine rotational speed NE has increased, and the rotational fluctuation amount DNE has decreased. When started, acceleration retard is executed (time t2). Thereafter, when DNE ≦ 0, | CEA | ≧ # CEAACCRM and CEA <0 is satisfied (step 90D: YES), that is, the engine speed NE has not increased and the rotational fluctuation amount DNE has increased. When starting to start, the acceleration retard is stopped (time t3).

  As described above, according to the present embodiment, the corrected rotational fluctuation amount CEA is calculated by correcting the rotational fluctuation amount DNE so as to have a predetermined phase lag according to the engine speed NE and the gear ratio of the transmission. When the corrected rotational fluctuation amount CEA becomes larger than 0 (when −DNE with a predetermined phase delay becomes smaller than 0), acceleration retard is executed. Therefore, the acceleration retard can be executed at a timing close to the optimal timing at which the vehicle driving force actually starts to increase, thereby effectively suppressing the vehicle longitudinal vibration. Also, in this embodiment, unlike the other embodiments, the calculation of the rotational fluctuation amount differential value DDNE becomes unnecessary, and accordingly, the processing load can be reduced, and the ignition timing control can be simplified. . Further, since the acceleration retard is executed or stopped on condition that the absolute value | CEA | of the corrected rotational fluctuation amount is equal to or greater than the threshold value #CEAACCRP or #CEAACCRM, the influence of the noise component on the rotational fluctuation amount DNE It is possible to eliminate the acceleration retard malfunction and hunting appropriately.

  FIG. 36 shows another example of the #IGACCRN table for stopping the air conditioner for setting the acceleration retard amount basic value IGACCRX used in step 54 of FIG. In the above-described #IGACCRN table in FIG. 10, the engine speed NE is used as the parameter, whereas in this table, the compensation engine signal value AES or the corrected DDNE is used. As described above, the rotational fluctuation amount differential value DDNE represents the degree (inclination) of the increase or decrease in the rotational fluctuation amount DNE, and the rotational fluctuation amount DNE has an opposite phase relationship with the vehicle driving force. The rotational fluctuation amount differential value represents the degree of increase or decrease of the vehicle driving force. Further, the compensation engine signal value AES and the correction DDNE are obtained by compensating the rotational fluctuation amount differential value DDNE for the amplitude center deviation due to the compression stroke fluctuation, and thus accurately reflect the degree of increase or decrease in the vehicle driving force.

  Therefore, by setting the acceleration retard amount basic value IGACCRX according to the compensation engine signal value AES or the correction DDNE as described above, the acceleration retard amount basic value IGACRRX is set according to the actual increase degree of the vehicle driving force. It can be set to an optimum value for canceling the increase in force, and thereby the vehicle longitudinal vibration can be more effectively suppressed. FIG. 36 shows an example of the #IGACCRN table for when the air conditioner is stopped, but it is needless to say that the #IGACCRAN table for operating the air conditioner may be configured similarly.

  In addition, this invention can be implemented in various aspects, without being limited to the described embodiment. For example, in the embodiment, the third predetermined value to be compared with the corrected rotational fluctuation amount CEA is set to a value 0 in order to determine whether to execute and stop the acceleration retard, but may be set to another appropriate value. Also good.

1 is a schematic configuration diagram of an ignition timing control device according to an embodiment of the present invention and an internal combustion engine to which the ignition timing control device is applied. It is a flowchart which shows the main flow of the calculation process of the ignition timing performed by the control apparatus of FIG. It is a flowchart which shows the calculation process of the acceleration retard correction amount by 1st Embodiment. It is a flowchart which shows the latter half part of the calculation process of FIG. It is a flowchart which shows the calculation subroutine of compensation engine signal value AES. It is an example of a # DDNEK / dtN table for setting an amplitude center shift compensation term DDNEK / dt. It is an example of a #DDNETDCN table for setting a calculated delay compensation term DDNETDC. It is a flowchart which shows the subroutine of the execution area | region determination process of the acceleration retard control performed by step 32 of FIG. It is an example of a #THACCRN table for setting a throttle opening determination value THACCR. FIG. 5 is an example of (a) a #IGACCRN table for stopping an air conditioner and (b) a #IGACCRAN table for operating an air conditioner for setting an acceleration retard amount basic value IGACCRX. It is an example of a #KTHACRN table for setting a throttle opening correction coefficient KTHACR. It is an example of a #KGRN table for setting the gear position correction coefficient KGR. FIG. 5 is a flowchart showing a subroutine for calculating an acceleration retard correction amount IGACCR executed in step 60 of FIG. 4. FIG. It is a flowchart which shows the second half part of the calculation process of FIG. It is a timing chart which shows the operation example obtained by the acceleration retard control of 1st Embodiment. It is a figure which shows the result of the test implemented by applying the acceleration retard control of 1st Embodiment. FIG. 6 is a flowchart corresponding to FIG. 3 and showing the first half of the processing for calculating the acceleration retard correction amount IGACR according to the second embodiment. FIG. 14 is a flowchart corresponding to FIG. 13 and showing the first half of a subroutine for calculating an acceleration retard correction amount IGACR according to a second embodiment. It is a timing chart which shows the operation example obtained by the acceleration retard control of 2nd Embodiment. FIG. 10 is a flowchart corresponding to FIG. 3 and showing the first half of the processing for calculating the acceleration retard correction amount IGACR according to the third embodiment. It is a flowchart which shows the calculation subroutine of correction | amendment DDNE. FIG. 14 is a flowchart corresponding to FIG. 13 and showing a first half of a subroutine for calculating an acceleration retard correction amount IGACR according to a third embodiment. It is a figure which shows the relationship of the phase of the optimal timing of acceleration retard, rotation fluctuation amount, and rotation fluctuation amount differential value. It is a figure which shows the shift | offset | difference time of the rotation fluctuation amount and rotation fluctuation amount differential value with respect to the optimal timing of acceleration retard. It is a timing chart which shows the example of operation obtained when an engine exists in a high-speed area by acceleration retard control of a 3rd embodiment. It is a timing chart which shows the example of operation obtained when an engine exists in a low-speed area by acceleration retard control of a 3rd embodiment. FIG. 14 is a flowchart corresponding to FIG. 13 and showing the first half of a subroutine for calculating an acceleration retard correction amount IGACR according to a fourth embodiment. It is a timing chart which shows the operation example obtained when an engine exists in a high-speed area by acceleration retard control of a 4th embodiment. It is a timing chart which shows the example of operation obtained when an engine exists in a low-speed area by acceleration retard control of a 3rd embodiment. FIG. 10 is a flowchart corresponding to FIG. 3 and showing the first half of the processing for calculating the acceleration retard correction amount IGACR according to the fourth embodiment. It is a flowchart which shows the calculation subroutine of correction | amendment rotation fluctuation amount CEA. It is an example of a #DNETDCN table for setting a TDC correction term DNETDC. It is an example of a #DNEGEARN table for setting a gear position correction term DNEGEAR. FIG. 14 is a flowchart corresponding to FIG. 13 and showing the first half of an acceleration retard correction amount IGACCR calculation subroutine according to the fifth embodiment. It is a timing chart which shows the operation example obtained by the acceleration retard control of 5th Embodiment. It is another example of the #IGACCRN table for the time of the air-conditioner stop for setting the acceleration retard amount basic value IGACCRX.

Explanation of symbols

1 Ignition timing control device
2 Internal combustion engine
3 ECU (acceleration request detection means, rotation speed detection means, rotation fluctuation amount calculation means, correction
(Rotational fluctuation amount calculating means, retard angle correction amount calculating means, retard angle correcting execution means)
6 Throttle opening sensor (acceleration request detection means)
15 Crank angle sensor (rotational speed detection means)
20 Gear position sensor (speed ratio detecting means)
NE engine speed DNE rotation fluctuation amount CEA correction rotation fluctuation amount IGLOG ignition timing IGACCR acceleration retard correction amount (retard angle correction amount)

Claims (1)

An ignition timing control device for an internal combustion engine that controls an ignition timing to a retard side during acceleration,
Acceleration request detecting means for detecting an acceleration request for the internal combustion engine;
A rotational speed detection means for detecting the rotational speed of the internal combustion engine;
A rotational fluctuation amount calculating means for calculating the rotational fluctuation amount of the internal combustion engine based on the detected rotational speed;
Gear ratio detecting means for detecting a gear ratio of a transmission connected to the internal combustion engine;
A corrected rotational fluctuation amount calculation for calculating a corrected rotational fluctuation amount by correcting the calculated rotational fluctuation amount so as to have a predetermined phase delay according to the rotational speed of the internal combustion engine and the detected gear ratio. Means,
A retard correction amount calculating means for calculating a retard correction amount for correcting the ignition timing to the retard side;
When the acceleration request is detected, when the correction rotation fluctuation amount is larger than a third predetermined value, retard correction execution means for executing correction by the retard correction amount;
An ignition timing control device for an internal combustion engine, comprising:

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