JP5212318B2 - Vehicle engine control device - Google Patents

Description

  The present invention relates to an engine control device for a vehicle that suppresses a forced rotation fluctuation force of an engine when a resonance caused by an engine fluctuation occurs, and more particularly to a technique for determining the occurrence of the resonance.

  Engine control apparatus for a vehicle that suppresses engine rotation fluctuation forcing when a predetermined condition for determining the occurrence of resonance due to engine rotation fluctuation (torque fluctuation) in the power transmission path from the engine to the drive wheels is satisfied Is well known. For example, this is the engine start-time control device described in Patent Document 1. Specifically, for example, as shown in the vibration model at the time of clutch engagement in FIG. 12A, in order to prevent the rotational fluctuation of the engine 1 from being transmitted to the tire 2 side, for example, the engine 1 and the transmission T A vehicle including a dual mass flywheel (hereinafter referred to as DMF) 3 in a power transmission path between / M and the drive shaft D / S is well known.

  The DMF 3 is formed by connecting two flywheels, for example, a primary flywheel J1 and a secondary flywheel J2 by an elastic member (spring, damper). Therefore, the DMF 3 has a resonance point (resonance frequency). On the other hand, in such DMF 3, the resonance point can be set relatively freely by adjusting the rotational inertia mass of each flywheel J1, J2 and the elastic force of the elastic member. For example, the resonance point of DMF 3 can be lowered by increasing the rotational inertia mass on the secondary flywheel J2 side. For example, as shown in FIG. 12 (b), the resonance point of DMF 3 can be set to a rotational speed range lower than the idle rotational speed of engine 1. As a result, a damping effect can be obtained in the engine normal use range that is equal to or higher than the idle rotation speed of the engine 1, so that the rotational fluctuation and torque fluctuation amount from the engine 1 can be attenuated.

  However, depending on the vehicle running state, the engine rotation speed may be lower than the idle rotation speed. If the resonance point of the DMF 3 is set to a rotation speed region lower than the idle rotation speed at this time, the engine is driven by the resonance of the DMF 3. There is a possibility that large torque fluctuations and shocks may occur due to amplification of rotational fluctuations. On the other hand, as shown in Patent Document 1, when the engine rotation speed stays in a predetermined resonance rotation speed region for a predetermined time, the resonance is achieved by stopping or suppressing the fuel supply to the engine 1. It is conceivable to leave the rotational speed region.

JP 2005-54601 A

  By the way, the above-described resonance determination based on whether or not the engine rotation speed remains in a predetermined resonance rotation speed region, that is, the resonance determination using only the engine rotation speed determines whether or not the DMF 3 is actually resonating. Not what you want. For this reason, there is a possibility that the DMF 3 is not actually resonating and a resonance determination is made, and for example, the fuel supply to the engine 1 is stopped. Then, when the engine rotation speed is lower than the idle rotation speed, the frequency of engine stall (hereinafter referred to as engine stall) may increase. That is, the engine stall resistance that makes it difficult to engine stall deteriorates. On the contrary, although the DMF 3 is actually resonating, the resonance determination is not made, and for example, there is a possibility that the state where the fuel supply to the engine 1 is not stopped is continued. Then, the engine rotation fluctuation is amplified by the resonance of the DMF 3 and a large torque fluctuation or shock is generated, and the durability of the engine 1 or the DMF 3 may be lowered. On the other hand, it is conceivable to improve the determination conditions for resonance determination and determine the occurrence of resonance with high accuracy. However, even if the occurrence of resonance is determined with high accuracy and the fuel supply to the engine 1 is stopped, variations in the effect of reducing vibration and noise generated in the vehicle such as torque fluctuation, sound, and shock may occur. There is sex. Therefore, when setting the conditions for determining resonance, it is necessary to consider a larger safety margin, and from the viewpoint of suppressing the occurrence frequency of engine stall, the accuracy of engine control at the time of resonance determination can be improved. desired. Such a problem is not known, and in order to accurately suppress the occurrence of torque fluctuation, sound, shock, etc. due to resonance (that is, to accurately suppress vibration and noise), the accuracy of engine control at the time of resonance determination is reduced. It has not yet been proposed for improvement.

  The present invention has been made against the background of the above circumstances, and the object of the present invention is to improve the accuracy of engine control at the time of resonance determination and accurately suppress vibration and noise generated in the vehicle. An object of the present invention is to provide a vehicle engine control device.

  In order to achieve the above object, the gist of the present invention is that (a) a predetermined condition for judging the occurrence of resonance due to the rotational fluctuation of the engine in the power transmission path from the engine to the drive wheels is established. An engine control device for a vehicle that suppresses the rotational fluctuation forcing force of the engine in such a case, and (b) when the predetermined condition is satisfied, the change speed of the engine rotational speed accompanying the rotational fluctuation is smaller than a predetermined value. Sometimes, it is to suppress the rotational fluctuation forcing force of the engine.

  In this case, when the change speed of the engine rotational speed accompanied by the rotational fluctuation becomes smaller than the predetermined value when the predetermined condition is satisfied, the rotational fluctuation forcing force of the engine is suppressed, so that the rotational fluctuation is accompanied. Compared to when the change speed of the engine rotation speed exceeds a predetermined value, the engine control at the time of resonance judgment that suppresses the engine rotational fluctuation forcing is at a substantially constant time when the energy for generating vibration and noise is small. Implemented with high accuracy. Therefore, in addition to further improving the effect of reducing vibration and noise generated in the vehicle, variation in the effect of reduction is also suppressed. That is, it is possible to improve the accuracy of engine control at the time of resonance determination and to suppress vibration and noise generated in the vehicle with high accuracy.

  For example, when resonance occurs when the engine is stopped, vibration and noise generated in the vehicle are further reduced. In addition, for example, at the time of engine stall at the time of resonance determination, it is possible to suppress the vibration and noise of the vehicle as much as possible. On the contrary, the vibration of the vehicle so that the driver can easily recognize the engine stall.・ Noise can be left moderately.

  Here, preferably, when the change speed of the engine rotational speed accompanying the rotational fluctuation is smaller than a predetermined value, the differential value of the actual value of the engine rotational speed or the average value of the engine rotational speed is zero. Or when it becomes smaller than the control timing judgment threshold value near zero. In this way, it is possible to accurately determine when the change speed of the engine rotation speed accompanying the rotation fluctuation is smaller than the predetermined value.

  Preferably, when the change speed of the engine rotation speed accompanying the rotation fluctuation becomes smaller than a predetermined value, the crank angle synchronized with the time when the crank angle becomes smaller is obtained in advance from the rotation fluctuation cycle of the engine. When the predetermined crank angle is reached. In this way, it is possible to accurately determine when the change speed of the engine rotation speed accompanying the rotation fluctuation is smaller than the predetermined value.

  Further, preferably, the rotational fluctuation forcing force of the engine is suppressed by stopping or suppressing the fuel supply to the engine. If it does in this way, engine rotation fluctuation forcing will be controlled appropriately.

  Preferably, the rotational fluctuation forcing force of the engine is suppressed by suppressing the amount of intake air to the engine. If it does in this way, engine rotation fluctuation forcing will be controlled appropriately.

  Preferably, the rotational fluctuation forcing force of the engine is suppressed by changing the combustion timing of the engine. If it does in this way, engine rotation fluctuation forcing will be controlled appropriately.

  Preferably, the power transmission path is provided with a damper, and an output from the engine is transmitted to the drive wheel side via the damper. In this way, resonance caused by fluctuations in engine rotation may be generated by the damper, whereas the engine control at the time of determining the resonance of the damper has a relatively small energy that generates vibration and noise. It is carried out with good accuracy at the time of.

  Preferably, the damper is a dual mass flywheel in which two flywheels are connected by an elastic member, and a resonance point of the dual mass flywheel has a rotational speed range lower than an idle rotational speed of the engine. Is set in advance. If it does in this way, the vibration and noise which generate | occur | produce in a vehicle can be suppressed with sufficient precision with respect to passing the resonance point of a dual mass flywheel, for example at the time of an engine stop. In addition, for example, when passing through the resonance point of the dual mass flywheel when the engine speed decreases due to a decrease in vehicle speed, the vibration and noise generated in the vehicle are accurately suppressed, and the engine control at the time of resonance determination is reduced. Can be made. At the time of the engine stall, the vibration and noise of the vehicle can be suppressed as much as possible. On the contrary, the vibration and noise of the vehicle can be appropriately left so that the driver can easily recognize the engine stall.

  Preferably, the predetermined condition is that the average value of the engine rotational speed is lower than a first predetermined threshold value obtained by adding a predetermined safety width to the resonance point, and the average value of the engine rotational speed and the engine rotational speed are The difference in rotational speed from the actual value is higher than a second predetermined threshold for determining resonance, and in addition to the predetermined condition, the change speed of the engine rotational speed accompanying the rotational fluctuation is smaller than a predetermined value. When determining the time, the predetermined safety width is set smaller and the second predetermined threshold is set larger than when only the predetermined condition is determined. In this way, for example, when setting the predetermined condition, compared with the case where the resonance determination is performed only under the predetermined condition, the safety width that must be taken into consideration is suppressed, and the timing of the resonance determination is further increased. Since it is delayed, it is possible to improve the engine stall resistance so that the engine stall is not desired. Therefore, the accuracy of engine control at the time of resonance determination can be improved to suppress variations in the reduction effect of vibration and noise generated in the vehicle, and both improvement in engine stall resistance and suppression of vibration and noise due to resonance can be achieved. .

  Preferably, the vehicle includes a vehicle power transmission device in the power transmission path from the engine to the drive wheel. The vehicle power transmission device includes a transmission mechanism unit alone, a torque converter, a transmission mechanism unit having a plurality of transmission ratios, or a speed reduction mechanism unit and a differential mechanism unit in addition to the transmission mechanism unit. In the speed change mechanism portion, a plurality of gear stages (shift speeds) are selectively achieved by selectively connecting rotating elements of a plurality of sets of planetary gear devices by an engagement device, for example, forward four speeds, forward speeds Various planetary gear type automatic transmissions having 5 speeds, 6 forward speeds, and more, etc., and a plurality of pairs of transmission gears that always mesh with each other between two shafts, and any of these multiple pairs of transmission gears Is a synchronous mesh type parallel twin-shaft transmission that is alternatively in a power transmission state by a synchronizer, and the gear stage is automatically controlled by a synchronizer driven by a hydraulic actuator, although it is a synchronous mesh type parallel twin-shaft transmission. A synchronous mesh type parallel twin-shaft automatic transmission that can be switched to a transmission belt, a transmission belt that functions as a power transmission member is wound around a pair of variable pulleys having a variable effective diameter, and the gear ratio is continuously steplessly Can be changed An automatic transmission that is a so-called belt-type continuously variable transmission, a pair of cones that are rotated around a common axis and a plurality of rollers that can rotate around the axis are sandwiched between the pair of cones. The automatic transmission, which is a so-called traction type continuously variable transmission in which the transmission gear ratio is variable by changing the crossing angle between the rotation center of the roller and the shaft center, the power from the engine, the first electric motor and the output A main part of the power from the engine is provided by a differential action of the differential mechanism including a differential mechanism constituted by, for example, a planetary gear device that distributes the shaft and a second electric motor provided on the output shaft of the differential mechanism Is electrically transmitted to the drive wheel side, and the remainder of the power from the engine is electrically transmitted using an electrical path from the first motor to the second motor. As a step transmission Automatic transmission ability, or composed of an automatic transmission capable of transmitting power to the electric motor is mounted on a so-called parallel hybrid vehicle provided in such an engine shaft and the output shaft.

  Preferably, an engine that is an internal combustion engine such as a gasoline engine or a diesel engine is widely used as the engine.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the schematic structure of the power transmission path | route including the manual transmission etc. which comprise the vehicle to which this invention is applied, and the principal part of the control system provided in the vehicle in order to control an engine etc. is demonstrated. It is a block diagram. It is a figure which shows an example of the waveform of the engine speed which falls with a vehicle speed by accelerator-off and brake-on with a clutch being engaged, when a manual transmission is maintained at a certain gear stage. It is a figure which shows an example of the order analysis result of the engine rotation waveform shown in FIG. It is a figure for demonstrating the predetermined conditions at the time of performing engine control. It is a time chart which shows an example of the rotation fluctuation | variation of the engine (or secondary flywheel) at the time of a brake stall, the twist angle of DMF, and the acceleration of an engine (or secondary flywheel). It is a functional block diagram explaining the principal part of the control function by the electronic controller of FIG. 7 is a flowchart for explaining a control operation for improving the accuracy of engine control at the time of resonance determination, that is, controlling the vibration and noise generated in the vehicle with high accuracy. It is a time chart which shows an example at the time of performing the control action shown to the flowchart of FIG. When engine control according to the present embodiment is executed, the maximum input at the time of resonance is generated in each case where resonance is determined only under a predetermined condition and engine control is executed, and when such engine control is not executed. It is a figure which shows an example of the dispersion | variation in a torque. 10 is a chart showing an example of the effect of the guaranteed number of times in each case of FIG. 9. 7 is a flowchart for explaining a control operation for improving the accuracy of engine control at the time of resonance determination, that is, a control operation for accurately suppressing vibration and noise generated in the vehicle. It is another Example corresponding to. (A) is a figure which shows the prior art example of the vibration model in the vehicle provided with a dual mass flywheel in the power transmission path | route from an engine to a tire. (B) is a figure which shows the prior art example which set the resonance point of the dual mass flywheel to the rotational speed range lower than the idle rotational speed of an engine.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating a schematic configuration of a power transmission path from an engine 14 including a manual transmission 12 constituting a vehicle 10 to which the present invention is applied to a drive wheel 16, and controls the engine 14 and the like. FIG. 2 is a block diagram for explaining a main part of a control system provided in the vehicle 10 in order to do this. In FIG. 1, the power of an engine 14 that is an internal combustion engine as a driving power source for traveling is a rear stage side of a dual mass flywheel (DMF) 20 and a DMF 20 as dampers operatively connected to a crankshaft 18 of the engine 14. Is transmitted to the manual transmission 12 through a clutch 22 provided in the vehicle. Then, it is transmitted to the pair of drive wheels 16 through the propeller shaft 24, the differential gear device (differential gear) 26, the pair of drive shafts 28, and the like through a shift by the manual transmission 12.

The engine 14 is, for example, an in-line four-cylinder diesel engine, and an injector (fuel injection valve) 30 for directly injecting fuel into the combustion chamber is provided in each cylinder (not shown). High-pressure fuel supplied from a supply pump (not shown) is stored in the common rail 32 and is injected into the cylinder by the injector 30. At this time, the fuel injection amount and the injection timing are controlled by sending a predetermined injection signal to the electromagnetic control valve of the injector 30. The intake pipe 34 of the engine 14 is provided with an electronic throttle valve 36 for restricting the intake air amount (intake amount) Q _AIR , and a predetermined drive signal is sent to the throttle actuator 38 so that the electronic throttle valve 36 The throttle valve opening θ _TH is operated.

  The DMF 20 includes a primary flywheel 40 coupled to the crankshaft 18, a secondary flywheel 42 coupled to the clutch 22, and a spring 44 as an elastic member connecting the two flywheels 40 and 42. That is, the DMF 20 is a flywheel damper having a structure in which the flywheel is divided into two parts and a torsion mechanism (spring) is provided therebetween. Further, the primary flywheel 40 and the secondary flywheel 42 are connected to each other so that the respective rotation shafts 40 a and 42 a can be relatively rotated via a bearing 46. By arranging the DMF 20 configured in this way in the power transmission path, the transmission of rotational fluctuations (torque fluctuations, output fluctuations) of the engine 14 to the drive wheel 16 side is reduced.

  Since the DMF 20 has two flywheels 40 and 42 connected by a spring 44, the DMF 20 has a resonance point (resonance frequency). This resonance point can be set relatively freely by adjusting the rotational inertia mass of each flywheel 40, 42 and the elastic force of the spring 44. Therefore, in this embodiment, for example, the resonance point of the DMF 20 is set to a rotational speed range lower than the idle rotational speed of the engine 14 by taking a large rotational inertia mass on the secondary flywheel 42 side. For example, in a rotational speed range lower than the idle rotational speed of the engine 14, the engine 14, the primary flywheel 40, etc. can swing as a rotational inertia mass in the vehicle vibration model when the clutch 22 is engaged (see FIG. 12A). There is a power train primary (torsion) resonance region (3 to 5 Hz) and a power train secondary (torsion) resonance region (10 to 20 Hz) in which the secondary flywheel 42, the manual transmission 12, and the like swing as a rotary inertia mass. (See FIG. 12B). Further, in a rotational speed range that is equal to or higher than the idle rotational speed of the engine 14, there is a power train tertiary resonance region in which the drive wheels 16 can be swung as a rotary inertia mass. As a result, a damping effect is obtained in the engine normal use range equal to or higher than the idle rotation speed of the engine 14, and the rotational fluctuation and torque fluctuation amount from the engine 14 are attenuated.

  Further, the vehicle 10 is provided with an electronic control device 70 including an engine control device for controlling the operating state of the engine 14. The electronic control unit 70 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and follows a program stored in the ROM in advance. By performing signal processing, output control of the engine 30 is basically executed.

The electronic control unit 70, a crank position sensor 48 for detecting a crank position from a sensor or switch provided in the vehicle 10, which corresponds to, for example, a crank angle (position) A _{CR [°]} and the rotational speed N _E of the engine 14 The presence or absence of operation of the throttle position sensor 50 for detecting the opening angle of the electronic throttle valve 36 provided in the intake pipe 34, that is, the throttle valve opening _θTH , and the foot brake pedal 52 that is a service brake is detected. The brake switch 54 that outputs a brake operation signal B _ON indicating that the brake pedal is operated, and the clutch pedal 56 is detected by detecting whether or not the clutch pedal 56 for switching the engagement / release of the clutch 22 is operated. A clutch indicating clutch-on (that is, release of the clutch 22). Pitch operation signal clutch switch 58 for outputting a C _ON, the starter relay 60 for outputting a starter signal S _ON representing the starter on a detected whether or not the engine start during the engine starting by the starter (not shown) From the intake air amount sensor 62 that detects the intake air amount Q _AIR of the engine 14, the crank angle (position) A _CR [°], the engine speed N _E , the throttle valve opening θ _TH , the brake operation signal B _ON , the clutch Signals representing the operation signal C _ON , starter signal S _ON , intake air amount Q _{AIR and the} like are supplied to the electronic control unit 70. Furthermore, the vehicle 10 includes a vehicle speed sensor that detects the vehicle speed V, an accelerator opening sensor that detects an accelerator opening Acc that is an operation amount of an accelerator pedal that is depressed according to an acceleration request amount requested by the driver, and the like. Various signals are supplied from a sensor or a switch (not shown).

The electronic control unit 70 also controls an engine control command signal S _E for controlling the output of the engine 14, for example, a fuel injection amount for controlling the fuel injection amount from the injector 30 according to the various signals and various calculation results. A signal, a fuel injection timing signal for controlling the fuel injection timing from the injector 30, a drive signal for the throttle actuator 38 for controlling the opening and closing of the electronic throttle valve 36, and the like are output.

By the way, in the vehicle 10 equipped with the DMF 20 of the present embodiment, as described above, in the rotational speed range lower than the idle rotational speed of the engine 14, the power train centering on the lowest resonance point that can swing with the engine 14 as a mass. There is a primary resonance region and a power train secondary resonance region centered on the next lower resonance point determined by the DMF 20. Therefore, the rotation fluctuation when the engine rotational speed N _E is lower than the idling rotational speed resonance caused by the rotational fluctuation of the engine 14 is generated is amplified, a large torque fluctuation, sound, possibly shock or the like occurs is there.

FIG. 2 shows that when the manual transmission 12 is maintained at a certain gear stage, the vehicle speed is increased by turning off the accelerator 22 while the clutch 22 is engaged (ie, the accelerator opening degree Acc is set to a zero determination value) and braking on. a diagram showing a waveform (engine rotational waveform) of the engine speed N _E at which with a decrease in V decreases is constrained to the vehicle speed V, (b) the time 9.5 [sec] after the (a) FIG. That result in stalling the engine rotational speed N _E is lowered occurs with a decrease in the vehicle speed V by a brake-on as shown in FIG. 2 is referred to as a brake stall. FIG. 3 is a diagram showing the order analysis result of the engine rotation waveform shown in FIG. In the order of FIG. 3, for example, in a four-cylinder four-cycle engine, 0.5th rotation means combustion once in 2 rotations, and 2nd rotation means combustion twice in one rotation. In FIG. 3, the magnitude of the amplitude, that is, the strength of the vibration intensity is represented by black and white shading, and the vibration intensity increases as the density increases. In Figure 2, large torque variation due to the resonance sound, shock, etc., the rotational fluctuation (Lord rotated quadratic component) of the engine 14 is high in the first power train secondary resonance region due to the reduction of the engine rotational speed N _E It is generated by being amplified on the rotation side (for example, around 600 rpm). Then, the engine rotational speed N _E remains with the energy shifts decreased to the power train primary resonance range. At this time, since the influence of the piston inertia of the engine 14 becomes dominant, a larger torque fluctuation, sound, shock, etc. are generated due to the resonance in the rotation 0.5 order component and the power train primary resonance region. Thereby, durability, such as the engine 14 and DMF20, may fall. The fuel by the time the engine rotational speed N _E with decreasing vehicle speed V becomes lower than the idling speed by the brake on, to maintain the engine rotational speed N _E (so as not to stall) engine control as shown in FIG. 2 When so-called ISC control (idle speed control) for increasing the injection amount is executed, the rotational fluctuation forcing force of the engine 14 is increased, and the rotational fluctuation is further amplified by resonance and the engine 14 is stopped. May cause large torque fluctuations, noise, shocks, and the like.

Therefore, the electronic control unit 70 according to the present embodiment is configured so that the predetermined condition for determining the occurrence of resonance due to the rotational fluctuation of the engine 14 in the power transmission path from the engine 14 to the drive wheel 16 is satisfied. Suppresses rotational fluctuation forcing. For example, the electronic control unit 70 determines a predetermined condition for determining that the rotational fluctuation of the engine 14 is amplified in the secondary resonance region of the power train at the time of clutch-off when the manual transmission 12 is maintained at a certain gear stage. Is established, the engine control for suppressing the rotational fluctuation forcing force of the engine 14 is executed before the shift to the power train primary resonance region, thereby suppressing the occurrence of large torque fluctuation, sound, shock, and the like due to resonance. With reference to FIG. 4, the predetermined condition is, for example the actual engine rotational speed _{N E} (actual value of the engine rotational speed _{N E,} hereinafter, the instant that _{N E)} the mean value (hereinafter, referred to as the average _{N E)} is DMF20 by adding a predetermined safety margin to the resonance point determined by the first drops below a predetermined threshold value Th1 (threshold 1), and an average N _E and the moment N _E and the rotational speed difference of the absolute value of the variation speed .DELTA.N E of ₍₌ Whether or not | instantaneous N _E -average N _E |) is greater than a second predetermined threshold Th2 (threshold 2) for determining resonance. The threshold 1 is, for example, a judgment value set previously obtained for determining whether entered the power train secondary resonance area when the engine rotational speed N _E is lowered, for example, determined by the DMF20 It is set near the rotational speed (for example, 600 rpm) on the high-rotation side of the power train secondary resonance region with the resonance point (for example, 450 rpm) as the center. Therefore, in this case, the predetermined safe width corresponds to the rotational speed (150 rpm) from the resonance point determined by the DMF 20 up to the high rotational speed of the power train secondary resonance region. The threshold value 2 is a determination value obtained and set in advance, for example, for determining that the rotational fluctuation of the engine 14 has been amplified, and is set to, for example, about 100 to 200 rpm.

The engine control that suppresses the rotational fluctuation forcing force of the engine 14 when the predetermined condition is satisfied suppresses the occurrence of large torque fluctuation, sound, shock, etc. due to resonance at the time of the brake stall, for example, This suppresses a decrease in durability. However, since such engine control results in engine stall, it may be difficult to achieve both improved engine stall resistance and suppression of large torque fluctuations, noise, shock, etc. due to resonance. . That is, for example, to higher the threshold 1, by or smaller the threshold 2, establishment i.e. resonance determination of the predetermined condition in the engine rotational speed N _E during reduction is made more high engine rotation side By doing so, it is advantageous for suppressing large torque fluctuations, noise, shocks, and the like due to resonance, but it is easy to generate engine stall, which is disadvantageous for engine stall resistance. On the other hand, in order to improve the engine stall resistance, for example, by lowering the threshold value 1 or increasing the threshold value 2, the predetermined condition is satisfied on the resonance point side determined by the DMF 20. By doing so, large torque fluctuations, sounds, shocks, etc. are likely to occur due to resonance. Further, improving the engine stall resistance is also related to improving the fuel consumption by maintaining the vehicle running as much as possible even when the engine speed _NE is lower than the idle speed. Furthermore, the more it is advantageous to suppress large torque fluctuations, noise, shocks, etc. due to resonance, the engine stalls more quietly, which may be disadvantageous in making the driver recognize the engine stall. . Thus, there exists a subject of improving each contradictory performance.

  In addition to the above-described problems, even if engine control is performed that suppresses the rotational fluctuation forcing force of the engine 14 by performing resonance determination under the same predetermined conditions, large torque fluctuation due to resonance, sound, shock, etc. occur in the vehicle. Variations may occur in the effect of reducing vibration and noise. Therefore, when setting the threshold value 1 and the threshold value 2, it is necessary to consider a larger safety margin. From the viewpoint of suppressing the occurrence frequency of engine stall (from the viewpoint of engine stall resistance), the accuracy of the engine control is improved. There is a need to improve. That is, there is a possibility that it is difficult to improve each performance by executing the engine control only by satisfying the predetermined condition.

A mechanism for causing variation in the above-described reduction effect of vibration and noise will be described below. FIG. 5 shows the rotational fluctuation speed (same as the rotational speed) of the engine 14 (or the secondary flywheel 42), the twist angle of the DMF 20 and the acceleration (that is, the rotational speed) of the engine 14 (or the secondary flywheel 42) at the time of brake stall. It is a time chart which shows a differential value. 5, as shown in time t1 and time t3, when the change rate of the engine rotation speed N _E with the rotational fluctuation is large (i.e. acceleration of the engine 14 (when the differential value of the engine rotational speed N _E) is large) Has generated a large torque due to resonance (that is, the torsion angle of the DMF 20 is increased by resonance). Conversely, as shown in time point t2 and time t4, when the change rate of the engine rotation speed N _E with the rotational fluctuation is small (for example the engine rotational speed N _E of the differential value is zero or zero near i.e. engine speed N _E In the vicinity of the peak value or the peak value), the twist angle of the DMF 20 is extremely reduced.

For this reason, when engine control that suppresses the rotational fluctuation forcing force of the engine 14 at the time t1 or t3 is performed, the energy that amplifies the rotational fluctuation of the engine 14 (energy that generates vibration and noise) is large, so it is very quiet. The engine 14 can not be stopped. On the other hand, when engine control is performed to suppress the rotational fluctuation forcing force of the engine 14 at time t2 or t4, the engine 14 can be stopped relatively quietly because the energy for amplifying the rotational fluctuation of the engine 14 is small. Therefore, if engine control that suppresses the rotational fluctuation forcing force of the engine 14 by simply performing resonance determination under the same predetermined condition is performed, there is a possibility that variations in the reduction effect of vibration, noise, etc. may occur. In other viewpoint, in addition to resonate determined under a predetermined condition, executing the engine control when the rate of change of the engine rotational speed N _E with the rotational fluctuation is small, the effect of reducing such above a certain vibration and noise In addition to being obtained, variation in the reduction effect is also suppressed.

Therefore, the electronic control device 70 of this embodiment, in a state where the predetermined condition is satisfied, the rate of change of the engine rotational speed N _E with the rotational fluctuation (hereinafter, referred to as the engine rotation speed variation rate) is smaller than a predetermined value At times (instant, timing), the rotational fluctuation forcing force of the engine 14 is suppressed. As a result, the engine control for suppressing the rotational fluctuation forcing force of the engine 14 is accurately performed at a substantially constant time when the energy for generating vibration and noise is small.

  Further, in addition to the predetermined condition, when determining when the engine rotational speed change rate is smaller than a predetermined value, since the effect of reducing vibrations and noises above a certain level can be obtained with high accuracy, Compared to the case where only the condition is judged, the predetermined safety width may be made smaller and the threshold value 1 may be set lower and the threshold value 2 may be set larger. This is because the engine 14 can be stopped stably and quietly as compared with the case where only the predetermined condition is determined. Thereby, since the timing of the resonance determination is delayed further, the engine stall resistance is improved. In addition, the fact that the engine 14 can be stopped with higher accuracy than when only the predetermined condition is determined, of course, can suppress the vibration and noise of the vehicle as much as possible. This also means that the engine control can be executed so that the driver can easily recognize the engine stall so that the vibration and noise of the vehicle remain moderate.

More specifically, FIG. 6 is a functional block diagram for explaining a main part of the control function by the electronic control unit 70. 6, the running state determining portion, that traveling state determining section 72 determines whether the clutch 22 is a seamed clutch off based on the clutch operation signal C _ON representing the clutch-on. The running state determining means 72 determines whether there is a starter off not being engine starting based on the starter signal S _ON representing the starter ON. Further, the traveling state determination unit 72 determines whether or not the brake pedal is turned on when the foot brake pedal 52 is operated based on the brake operation signal B _ON indicating that the brake pedal is on.

Predetermined condition establishment determining portion, that a predetermined condition establishment determining unit 74 determines whether or not lower than the threshold value 1 is the average N _E (first predetermined threshold Th1). Further, the predetermined condition establishment determination means 74 determines whether or not the fluctuation rotational speed ΔN _E (= | instantaneous N _E −average N _E |) is greater than the threshold 2 (second predetermined threshold Th2).

Control timing determining unit or control timing determining unit 76, whether the engine rotational speed change rate is smaller than a predetermined value, for example, the absolute value of a differential value of the instantaneous N _E (| d instant N _{E /} dt |) or an average absolute value of a differential value of N _E (| d average N _{E /} dt |) is determined based on whether it is smaller than the threshold value 3 as a control timing determination threshold zero or near zero. For example, when the energy for amplifying the rotational fluctuation of the engine 14 is small, the threshold 3 is set to a certain level or more with respect to the occurrence of vibration, noise, etc. due to resonance when engine control for suppressing the rotational fluctuation forcing of the engine 14 is executed. This is a determination threshold value obtained in advance for obtaining a reduction effect and suppressing variations in the reduction effect.

The engine control unit, that is, the engine control means 78, the clutch-off by the traveling state determining section 72, the starter off, and is determined to be a brake pedal ON, lower than the threshold value 1 is the average N _E by a predetermined condition establishment determining unit 74 In addition, it is determined that the fluctuation rotational speed ΔN _E has increased beyond the threshold value 2, and the engine speed determination means 76 (| d instantaneous N _E / dt | or | d average N _E / dt |) by the control timing determination means 76. Is determined to be smaller than the threshold 3, the rotational fluctuation forcing force of the engine 14 is suppressed. For example, the engine control unit 78 as an engine control command signals S _E, stop or suppress the fuel injection amount signal of the fuel injection amount from the injector 30, the fuel injection timing from the injector 30 for changing the combustion timing of the engine 14 At least one of a fuel injection timing signal for delaying the valve timing and a drive signal for fully closing the electronic throttle valve 36 for reducing the amount of intake air to the engine 14 or reducing the opening of the electronic throttle valve 36. It outputs and suppresses or eliminates the rotational fluctuation forcing force of the engine 14.

  FIG. 7 is a flowchart for explaining the control operation for accurately suppressing the vibration and noise generated in the vehicle by improving the accuracy of engine control at the time of resonance determination, that is, the main part of the control operation of the electronic control unit 70, For example, it is repeatedly executed with an extremely short cycle time of about several milliseconds to several tens of milliseconds.

7, first, steps corresponding to the running state determining means 72 (hereinafter, omitted step) In S10, whether the clutch 22 on the basis of the clutch operation signal C _ON is the spliced clutch off Determined. In addition, whether or not there is a starter off not being the engine start is determined on the basis of the starter signal S _ON. Step S20 similarly corresponding to the running state determining section 72 if the determination in S10 is affirmative, it is determined whether there is a brake pedal on the foot brake pedal 52 is operated on the basis of a brake operation signal B _ON is The In S30 corresponding to the predetermined condition establishment determining unit 74 when the determination in S20 is affirmative, whether or not the average N _E is lower than the threshold value 1 is determined. If the determination in S30 is affirmative, whether or not the fluctuation rotational speed ΔN _E (= | instantaneous N _E −average N _E |) has increased beyond the threshold 2 in S40 corresponding to the predetermined condition establishment determination means 74. Is determined. If the determination in S40 is affirmative, the engine speed change speed (| d instantaneous N _E / dt | or | d average N _E / dt |) is greater than the threshold 3 in S50 corresponding to the control timing determination means 76. It is determined whether or not the value has also decreased. If any one of the determinations of S10, S20, S30, S40, and S50 is negative, this routine is terminated. If the determination of S50 is positive, the routine corresponds to the engine control means 78. in S60 to, for example, as an engine control command signals S _E, stop or suppress the fuel injection amount of the fuel injection amount from the injector 30 signals, fuel injection timing signal for retarding the fuel injection timing from the injector 30, and an electronic throttle valve A drive signal for fully closing 36 is output, and engine stop control for eliminating the rotational fluctuation forcing force of the engine 14 is executed.

FIG. 8 is a time chart when the control operation shown in the flowchart of FIG. 7 is executed. FIG. 8 shows a time chart in a case where engine control for suppressing the rotational fluctuation forcing force of the engine 14 is not executed, and the two are compared. In the case of executing the control operation of this embodiment, as compared with the case of not executed, for example, variation speed .DELTA.N _E in the power train primary resonance region is decreased. In the power train primary resonance region, for example, the maximum sound pressure is reduced from 115 dB to 89 dB, and the impact sound is suppressed. For example, vehicle acceleration is reduced from 1.2 G to 0.5 G, and vehicle vibration is suppressed. Further, for example, the generated torque in the engine 14 is reduced from 2900 Nm to 1300 Nm, and the impact torque (impact torque) is suppressed.

FIG. 9 shows the case where the engine control of the present embodiment is executed (marked with ●), the case where the resonance control is performed only under a predetermined condition and the engine control is executed (marked with ◇), and the case where such engine control is not executed. It is a figure which shows the dispersion | variation in the maximum input torque (impact torque) at the time of resonance generation | occurrence | production in each case of ((circle)). FIG. 10 is a chart showing the effect of the guaranteed number of times in each case. 9 and 10, in the case of executing the engine control of this embodiment, as compared with the case of executing only the resonance determined by the engine control under a predetermined condition, the engine stall until a lower rotation side of the average N _E is It becomes difficult to occur, and the impact torque is kept low and the variation is also suppressed. For this reason, the number of guarantees (the number of times resonance occurs until it is determined that the durability of the engine 14, the DMF 20, etc. has been impaired) has increased by several stages. Also, compared with the case where such engine control is not executed, although the engine resistance is slightly inferior, the impact torque is further reduced while the variation is suppressed, so the number of guarantees is significantly increased. Yes. As described above, the engine control according to the present embodiment significantly reduces torque fluctuations, sounds, shocks, and the like without increasing costs due to the addition of devices (parts). Thereby, strength reliability of parts, such as engine 14, engine auxiliary machine parts, DMF20, etc. improves, for example. In other words, parts can be downsized, cost can be reduced, and weight can be reduced by reducing input torque. Further, drivability is improved as a whole of the vehicle 10 by reducing vibration and noise and improving the engine stall resistance.

As described above, according to this embodiment, the engine rotation speed variation rate when becomes smaller than a predetermined value, for example, an average N _E is lower than the threshold 1 and the variation speed in a state in which the predetermined condition is satisfied differential value of the instantaneous N _E at establishment state of the determined predetermined conditions .DELTA.N _E is increased than the threshold value 2 (| d instant N _{E /} dt |) or the differential value of the average N _E (| d average N _{E /} dt When || becomes smaller than the control timing determination threshold value (threshold value 3) between zero and near zero, the rotational fluctuation forcing force of the engine 14 is suppressed, and therefore when the engine rotational speed change speed becomes larger than a predetermined value. In comparison, the engine control at the time of resonance determination for suppressing the rotational fluctuation forcing force of the engine 14 is accurately performed at a substantially constant time when the energy for generating vibration and noise is small. Therefore, the effect of reducing vibrations and noise generated in the vehicle 10 is further improved, and variation in the reduction effect is also suppressed. That is, the accuracy of engine control at the time of resonance determination can be improved and the vibration and noise generated in the vehicle 10 can be suppressed with high accuracy. For example, when resonance occurs when the engine is stopped, vibration and noise generated in the vehicle are further reduced. Further, for example, at the time of engine stall at the time of resonance determination, the vibration and noise of the vehicle 10 can be suppressed as much as possible. Conversely, the vehicle 10 can be easily recognized by the driver. The vibration and noise can be kept moderate.

Further, according to this embodiment, the engine rotation speed variation rate with time becomes smaller than the predetermined value, the instantaneous differential value of N _E (| d instant N _{E /} dt |) or the differential value of the average N _E ( When | d average N _E / dt |) is smaller than threshold value 3 as a control time determination threshold value between zero and near zero. In this way, it is accurately determined when the engine rotation speed change rate is smaller than the predetermined value.

  Further, according to the present embodiment, the fuel supply to the engine 14 is stopped or suppressed (that is, the fuel injection amount from the injector 30 is stopped or suppressed), and the combustion timing of the engine 14 is changed ( That is, the timing of fuel injection from the injector 30 is retarded) and the amount of intake air to the engine 14 is suppressed (that is, the electronic throttle valve 36 is fully closed or the opening of the electronic throttle valve 36 is reduced). The rotational fluctuation forcing force of the engine 14 is appropriately suppressed or eliminated by at least one engine control of the plurality of engine controls.

  Further, according to the present embodiment, in the vehicle 10 in which the output from the engine 14 is transmitted to the drive wheel 16 side via the DMF 20, there is a possibility that resonance due to the rotational fluctuation of the engine 14 is generated by the DMF 20. On the other hand, the engine control at the time of determining the resonance of the DMF 20 is accurately performed at a substantially constant time when the energy for generating vibration and noise is relatively small.

Further, according to the present embodiment, the resonance point of the DMF 20 is set in advance in a rotation speed range lower than the idle rotation speed of the engine 14, and for example, the vehicle passes the resonance point of the DMF 20 when the engine is stopped. 10 can be suppressed with high accuracy. Further, for example during the lowering the engine speed N _E with the vehicle speed V decreases relative to that passing through the resonance point of the DMF20, engine stall due to engine control at the time of resonance determined vibration and noise generated on the vehicle 10 to accurately suppress Can be made. At the time of the engine stall, the vibration and noise of the vehicle 10 can be suppressed as much as possible. Conversely, the driver can easily leave the vibration and noise of the vehicle 10 so that the driver can easily recognize the engine stall. it can.

Further, according to this embodiment, the predetermined condition, the average N _E is lower than the first predetermined threshold value Th1 by adding a predetermined safety margin to the resonance point determined in DMF20 (threshold 1) and vary the rotational speed .DELTA.N _E (= | Instantaneous N _E −average N _E |) is greater than a second predetermined threshold value Th2 (threshold value 2) for determining resonance. In addition to the predetermined condition, the engine rotational speed change rate is predetermined. When determining when the value is smaller than the value, the threshold value 1 is set lower and the threshold value 2 is set higher than when determining only the predetermined condition. In this way, for example, when setting the predetermined condition, compared with the case where the resonance determination is performed only under the predetermined condition, the safety width that must be taken into consideration is suppressed, and the timing of the resonance determination is further increased. Since it is delayed, the engine stall resistance is improved. Therefore, it is possible to improve the accuracy of engine control at the time of resonance determination, suppress variation in the reduction effect of vibration and noise generated in the vehicle 10, and achieve both improvement in engine stall resistance and suppression of vibration and noise due to resonance. it can.

  Next, another embodiment of the present invention will be described. In the following description, parts common to the embodiments are denoted by the same reference numerals and description thereof is omitted.

In the illustrated embodiment, as when the engine rotational speed change rate is smaller than the predetermined value, the instantaneous differential value of N _E (| d instant N _{E /} dt |) or the differential value of the average N _E (| d Mean N _{The case where E} / dt |) is smaller than the control timing determination threshold value (threshold value 3) from zero to near zero is illustrated. Here, the cycle of engine rotation fluctuation is synchronized with the explosion cylinder timing in the case of a 0.5th-order rotation, that is, a 4-cylinder 4-cycle engine (see FIG. 5). Moreover, the explosion cylinder timing correlated with the crank angle A _CR. Therefore, the instantaneous differential value of N _E from the zero or near zero in the control timing determination threshold (threshold 3) (| d instant N _{E /} dt |) or the average differential value of the N _E (| | d Average N _{E /} dt) The crank angle _ACR synchronized with the time when the angle becomes smaller is obtained in advance and set as a predetermined crank angle. For example, the predetermined crank angle is set based on the crank angle corresponding to the explosion cylinder timing. That is, in this embodiment, predetermined for the engine rotation speed variation rate as a time to be smaller than a predetermined value, the crank angle A _CR is obtained in advance from the rotational fluctuation cycle of the engine 14 as a crank angle which is synchronized with the time of the small When the crank angle is reached.

Specifically, returning to FIG. 6, the control timing determination unit 76 replaces the above-described embodiment with respect to whether or not the engine rotation speed change speed has become smaller than a predetermined value, for example, the crank angle _ACR is The determination is made based on whether or not the crank angle synchronized with the time when the engine speed decreases becomes a predetermined crank angle obtained in advance from the rotation fluctuation cycle of the engine 14.

  FIG. 11 is a flowchart for explaining a control operation for accurately controlling vibrations and noises generated in the vehicle by improving the accuracy of engine control at the time of resonance determination, that is, the main part of the control operation of the electronic control unit 70. For example, it is repeatedly executed with an extremely short cycle time of about several milliseconds to several tens of milliseconds. The flowchart of FIG. 11 is another embodiment corresponding to the flowchart of FIG. 7, and only the difference is that step S50 in FIG. 7 is step S50 '. Therefore, description of steps other than step S50 'will be omitted.

In FIG. 11, if the determination in S40 is affirmative, in S50 ′ corresponding to the control timing determination means 76, whether or not the engine rotational speed change speed has become smaller than a predetermined value, for example, the crank angle _ACR is It is determined whether or not a predetermined crank angle obtained in advance from the rotational fluctuation cycle of the engine 14 is obtained as a crank angle synchronized with a time when the engine rotational speed change speed becomes smaller than a predetermined value. If any one of the determinations of S10, S20, S30, S40, and S50 ′ is negative, this routine is terminated. If the determination of S50 ′ is affirmative, the engine control means 78 is completed. S60 corresponding to is executed.

As described above, according to this embodiment, the a when the engine rotational speed change rate is smaller than the predetermined value, the rotational fluctuation cycle of the engine 14 as a crank angle of the crank angle A _CR is synchronized with the time of the small Is the time when the predetermined crank angle is obtained in advance. In this way, it is accurately determined when the engine rotation speed change rate is smaller than the predetermined value.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

For example, in the illustrated embodiment has been implemented to suppress the engine control rotational fluctuation forcing the engine 14 when the clutch-off clutch 22 is spliced as one of the conditions is not limited to, the engine rotational speed N _E The present invention can also be applied to pull-in resonance of the DMF 20 that occurs when the clutch is turned on (when the clutch is disengaged) so as to enter the resonance region due to the release of the clutch when the pressure decreases. Even in such a case, the same effect as described above can be obtained.

  In the above-described embodiment, the engine control is performed to suppress the rotational fluctuation forcing force of the engine 14 on the condition that the brake pedal is turned on when the foot brake pedal 52 is operated. Considering that there is a vehicle state in which the vehicle speed V decreases even when the pedal is not on, it is not always necessary to set one of the conditions when the brake pedal is on. Therefore, the determination in step S20 in the flowcharts of FIGS. 7 and 11 is not necessarily required.

In the illustrated embodiment, the instantaneous differential value of N _E (| d instant N _{E /} dt |) or the differential value of the average N _E (| d Average N _{E /} dt |) when the is smaller than the threshold value 3 The engine control for suppressing the rotational fluctuation forcing force of the engine 14 was performed. This is to perform the engine control at a peak value or in the vicinity of the peak value in the engine rotation fluctuation without distinguishing between when the engine speed _NE is increasing and when the engine speed NE is decreasing. On the other hand, if there is a difference in the reduction effect of vibration, noise, etc. between when the engine rotational speed _NE is increased and when the engine speed NE is decreased, the above-mentioned peak value or near the peak value is obtained. You may make it implement engine control. For example, those who implement the engine control in the vicinity of the peak value to the peak value of the engine rotation fluctuation during lowering of the engine speed N _E, if I is confirmed in advance experimentally that can more gently stops the engine 14 Then, the engine control is carried out at the peak value of the engine rotation fluctuation or the vicinity of the peak value at the time of the descent.

In the illustrated embodiment, the predetermined condition, the average N _E is whether lower than the threshold 1, and the change speed .DELTA.N _E was whether increased than the threshold value 2. On the other hand, in order to improve the accuracy of the resonance determination, for example, the predetermined condition is satisfied in consideration of the control responsiveness due to the resonance point difference due to each gear stage of the manual transmission 12 and the engine lowering speed depending on the brake braking force. You may judge. Then, when the engine speed change rate becomes smaller than a predetermined value, engine control for suppressing the rotational fluctuation forcing force of the engine 14 may be performed. In this way, the effect of the present invention can be further obtained.

  In the above-described embodiment, the DMF 20 is provided in the power transmission path of the vehicle 10. However, the present invention is not limited thereto, and the present invention can be applied to any damper that generates resonance due to the rotational fluctuation of the engine 14. In addition, the damper is not necessarily provided, and the present invention can be applied to any vehicle 10 that generates resonance due to rotational fluctuation of the engine 14 in the power transmission path.

  Further, in the above-described embodiment, the engine control that suppresses the rotational fluctuation forcing force of the engine 14 is performed as a resonance countermeasure at the time of brake stall. However, the present invention is not limited to this, for example, an ignition stop or an idle stop when the vehicle is stopped. The present invention can also be applied as a countermeasure against resonance when the engine 14 is stopped by, for example. Accordingly, the vehicle 10 to which the present invention is applied is not limited to the vehicle including the illustrated manual transmission 12 as a power transmission device. For example, the power transmission device is a planetary gear type automatic transmission or a continuously variable type represented by a belt type. The present invention can also be applied to a vehicle including a transmission, a hybrid vehicle including an engine and an electric motor as driving force sources, and the like. In particular, in a hybrid vehicle, it is considered that the frequency of stopping the engine is increased. Therefore, joy by applying the present invention is easily obtained.

  Moreover, the numerical values indicated by the threshold value 1 and the threshold value 2 in the above-described embodiment are examples until the tiredness, and are not limited to this. For example, numerical values adapted to each vehicle are used.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

10: Vehicle 14: Engine 16: Drive wheel 20: Dual mass flywheel (damper)
40: Primary flywheel 42: Secondary flywheel 44: Spring (elastic member)
70: Electronic control device (engine control device)

Claims (9)

An engine control device for a vehicle that suppresses the rotational fluctuation forcing force of an engine when a predetermined condition for determining the occurrence of resonance due to the fluctuation of the rotation of the engine in a power transmission path from the engine to a drive wheel is satisfied. And
An engine control device for a vehicle, wherein when the predetermined condition is satisfied, an engine rotational fluctuation forcing force is suppressed when a change speed of an engine rotational speed accompanied by a rotational fluctuation becomes smaller than a predetermined value.   When the change speed of the engine rotational speed accompanying the rotational fluctuation is smaller than a predetermined value, the control timing determination when the differential value of the actual value of the engine rotational speed or the average value of the engine rotational speed is zero or near zero The vehicle engine control device according to claim 1, wherein the time is smaller than a threshold value.   When the change speed of the engine rotation speed accompanying the rotation fluctuation is smaller than a predetermined value, the crank angle synchronized with the crank angle is a predetermined crank angle obtained in advance from the rotation fluctuation cycle of the engine. The engine control device for a vehicle according to claim 1, wherein   4. The vehicle engine control apparatus according to claim 1, wherein the engine rotation fluctuation forcing force is suppressed by stopping or suppressing fuel supply to the engine. 5.   The vehicle engine control device according to any one of claims 1 to 4, wherein a rotational fluctuation forcing force of the engine is suppressed by suppressing an intake air amount to the engine.   6. The vehicle engine control device according to claim 1, wherein the engine rotational fluctuation forcing force is suppressed by changing a combustion timing of the engine. 7. The power transmission path is provided with a damper,
The vehicle engine control device according to any one of claims 1 to 6, wherein an output from the engine is transmitted to the drive wheel side through the damper. The damper is a dual mass flywheel in which two flywheels are connected by an elastic member,
8. The vehicle engine control apparatus according to claim 7, wherein a resonance point of the dual mass flywheel is set in advance in a rotational speed range lower than an idle rotational speed of the engine. The predetermined condition is that an average value of the engine rotational speed is lower than a first predetermined threshold value obtained by adding a predetermined safety width to the resonance point, and a differential rotation between the average value of the engine rotational speed and an actual value of the engine rotational speed is performed. The speed has increased above a second predetermined threshold for determining resonance;
In addition to the predetermined condition, the predetermined safety width is determined when it is determined when the change speed of the engine rotation speed accompanying the rotation fluctuation is smaller than a predetermined value, compared to when only the predetermined condition is determined. 9. The vehicle engine control apparatus according to claim 8, wherein the second predetermined threshold value is set to be large while the value is set small.

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