JP5370173B2 - Engine automatic stop / start control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for automatically stopping/starting an engine, smoothly executing restart of the engine, in the restart after a failed restart attempt. <P>SOLUTION: The control device for automatically stopping/starting an engine includes: a motor rotary driving a pinion; and a starter which can individually operate the motor and an actuator making the pinion mesh with a ring gear connected to a crankshaft of the engine. The control device automatically stops the engine when an engine automatic stop request is issued, and restarts the engine when an engine restart request is issued. The control device further includes a detection means S201 detecting failure in restart. When the detection means S201 detects the failure in restart, the execution of the restart is prohibited during a period from when the failure is detected to when an engine revolution speed is reduced to zero (S203). <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an engine automatic stop start control device that automatically stops an engine when an engine automatic stop request is generated and restarts the engine when an engine restart request is generated.

  In recent years, some vehicles equipped with an engine (internal combustion engine) employ an engine automatic stop / start control system (so-called idle stop control system) for the purpose of reducing fuel consumption and exhaust emission. This engine automatic stop / start control system automatically stops the engine when the driver stops the vehicle, for example, and then automatically when the driver performs an operation to start the vehicle. The engine is cranked with a starter and restarted.

  Generally, a starter rotates a pinion with a motor, pushes out the pinion with an actuator, meshes the pinion with a ring gear connected to the crankshaft of the engine, and drives the ring gear to rotate so that the engine is cranked. It has become. However, if the pinion tries to mesh with the ring gear in a state where the difference in rotational speed between the pinion and the ring gear is large, the pinion may not mesh smoothly with the ring gear and noise may be generated.

  Therefore, as described in Patent Document 1, when an engine restart request is generated during an engine rotation descent period in which the engine rotation speed decreases due to the automatic engine stop immediately after the engine automatic stop request is generated, After that, when the engine rotation (rotation of the ring gear) becomes low just before stopping, the starter pinion is pushed out and meshed with the ring gear, and then the pinion is rotated and cranking is started to restart the engine. There is something to let you do. Hereinafter, restart by this method is referred to as “first-out control”.

  However, in this first-out control, after the engine restart request is generated, the engine rotation is almost stopped and the cranking is started. Therefore, the delay from the engine restart request to the engine restart increases. This may cause the driver to feel that the engine restart is slow.

  As a countermeasure against this, as described in Patent Documents 2 and 3, when an engine restart request is generated during the engine rotation drop period due to the automatic engine stop, the rotation speed of the pinion is synchronized with the rotation speed of the ring gear. Then, after reducing the difference in rotational speed between the two, the pinion is pushed out and meshed with a ring gear to start cranking, whereby the engine is restarted. Hereinafter, restart by this method is referred to as “advance control”.

  However, if the engine speed at the time when the engine restart request is generated is high to some extent, the engine can be restarted by injecting fuel without performing cranking by the starter. Hereinafter, restart by this method is referred to as “autonomous return control”.

  Therefore, in Patent Document 3, if the engine rotation speed at the time when the engine restart request is generated is a first rotation speed region that is higher than the first rotation speed, autonomous return control is performed, and the first rotation speed or less is performed. In the second rotation speed region higher than the second rotation speed, the advance control is performed, and in the third rotation speed region equal to or lower than the second rotation speed, the advance control is performed.

JP 2002-122059 A Japanese Patent Laying-Open No. 2005-330813 JP 2002-70699 A

  However, even if the autonomous return control is performed, restart may fail due to engine malfunction such as failure to obtain desired combustion. In addition, even if the forward control is performed, the pinion is pushed out in a state where it is not accurately synchronized, so that the engagement with the ring gear fails, or the teeth of the pinion or ring gear have deteriorated over time (worn). In some cases, the meshing may fail and restart may fail. Even if the advance control is performed, the meshing may fail due to the above-mentioned deterioration over time and the restart may fail.

  In the control method described in Patent Document 3, for example, when restart by autonomous return control fails, advance control is performed as the engine rotational speed falls to the second rotational speed region. . However, it is difficult to predict the behavior of the engine rotation speed immediately after the failure of restart, and it is also difficult to grasp the motor rotation speed because the starter motor rotates in inertia. Therefore, when the control is performed in advance during the engine rotation descent period after the restart failure, it is extremely difficult to engage the pinion at the synchronized timing. Therefore, the pinion cannot be smoothly meshed with the ring gear, and there is a concern about significant wear damage of the ring gear or the pinion.

  Even when the advance control is performed as the engine speed drops to the third rotation speed range after the restart failure due to the advance control, the behavior of the engine speed immediately after the restart failure is predicted. Since it is difficult, there is a concern that the pinion is pushed out in the second rotation speed region. Therefore, the pinion cannot be smoothly meshed with the ring gear, and there is a concern about significant wear damage of the ring gear or the pinion.

  In addition, even when the autonomous return control is performed again due to the engine speed being in the first rotational speed region after the restart failure due to the autonomous return control, the behavior of the engine speed immediately after the restart failure is predicted. Since it is difficult, there is a concern that the autonomous return control may be performed in the second rotation speed region, and in this case, the restart fails again.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and its purpose is to automatically stop the engine so that it can be smoothly restarted when attempting to restart again after the engine restart fails. It is to provide a start control device.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  According to the first aspect of the present invention, there is provided a starter capable of individually operating a motor that rotationally drives the pinion and an actuator that meshes the pinion with a ring gear that is connected to the crankshaft of the engine, and an automatic engine stop request is generated. It is presupposed that the engine is automatically stopped and started and the engine is restarted when the engine restart request is generated. And it comprises a detecting means for detecting that the restart has failed, and when the restarting failure is detected by the detecting means, a period from when the failure is detected until the engine rotation speed becomes zero, Implementation of the restart is prohibited.

  According to this, since restart is prohibited during the engine rotation descent period in which it is difficult to accurately grasp the engine rotation speed and the starter motor rotation speed immediately after the restart has failed, When trying to restart again after a failure of restart, it is possible to avoid a problem that the pinion cannot be smoothly meshed with the ring gear, and in turn, avoid significant wear damage of the ring gear or pinion.

  In the above invention, both the case where the restart request is generated during the engine rotation descent period (case 1) and the case where the restart request is generated while the engine rotation is stopped (case 2) are assumed. In the case of 2, the engine speed is slightly increased due to the failed restart, and then the restart is prohibited during a period until it drops to zero. Moreover, the said case 1 is assumed about Claims 2-5 demonstrated below.

  In the second aspect of the present invention, cranking is not performed when a restart request is generated in the first rotation speed region in which the engine rotation speed is higher than the first rotation speed during the engine rotation descent period due to automatic stop. And a second rotational speed region in which the engine rotational speed is equal to or lower than the first rotational speed and lower than the first rotational speed during the engine rotational descent period. When a restart request is generated in the engine, a pre-rotation control unit that synchronizes the rotation speed of the pinion with the rotation speed of the ring gear and then restarts by engaging the pinion with the ring gear; and during the engine rotation descent period When the restart request is generated in the third rotation speed region where the engine rotation speed is less than or equal to the second rotation speed, the pinion is engaged with the ring gear. Or rotating the pinion in the middle of engagement thereof after and a first-out control means for restart.

  And further comprising detection means for detecting that the restart by any one of the autonomous return control, the advance control and the advance control has failed, and when the restart failure is detected by the detection means. Is characterized by prohibiting the execution of the autonomous return control, the advance control and the advance control during a period from when the failure is detected until the engine rotation speed becomes zero.

  According to this, it is immediately after failure to restart by any one of the autonomous return control, the advance control and the advance control, and it is difficult to accurately grasp the engine speed and the motor speed of the starter. During the period, the execution of autonomous return control, advance control and advance control is prohibited, so when trying to restart again after a restart failure, it is possible to avoid problems such as being unable to smoothly mesh the pinion with the ring gear, As a result, significant wear damage of the ring gear or pinion can be avoided. Further, it is possible to avoid a problem that the autonomous return control fails again immediately after the autonomous return control fails.

  The invention according to claim 3 includes the autonomous return control means and the advance control means described above, and further includes a detection means for detecting that the restart by either the autonomous return control or the advance control has failed, When the failure of the restart is detected by the detection means, the autonomous return control and the advance control are prohibited from being performed during the period from the failure detection time until the engine rotation speed becomes zero. To do.

  According to this, immediately after the restart due to either the autonomous return control or the advance control fails, and during the engine rotation descent period in which it is difficult to accurately grasp the engine rotation speed and the starter motor rotation speed, Since the implementation of autonomous return control and advance control is prohibited, it is possible to avoid problems such as the inability to smoothly mesh the pinion with the ring gear when attempting to restart again after a restart failure, and consequently significant wear damage to the ring gear or pinion. Can be avoided. Further, it is possible to avoid a problem that the autonomous return control fails again immediately after the autonomous return control fails.

  The invention according to claim 4 includes the above-mentioned advance control means and advance control means, and further includes detection means for detecting that the restart by either of the advance control or the advance control has failed, When the failure of the restart is detected by the detection means, the advance control and the advance control are prohibited during the period from the failure detection time until the engine rotation speed becomes zero. To do.

  According to this, immediately after the failure of the restart by either the advance control or the advance control, it is difficult to accurately grasp the engine rotation speed and the motor rotation speed of the starter. Since the advance control and advance control are prohibited, it is possible to avoid the trouble that the pinion cannot be smoothly meshed with the ring gear when trying to restart again after the restart failure, and in turn, the ring gear or pinion is significantly worn and damaged. Can be avoided.

  The invention according to claim 5 includes the above-mentioned advance control means, and further includes a detection means for detecting that the restart by the advance control has failed, and when the restart failure is detected by the detection means. Is characterized in that the advance control is prohibited during a period from when the failure is detected until the engine speed becomes zero.

  According to this, in the engine rotation descent period in which it is difficult to accurately grasp the engine rotation speed and the starter motor rotation speed immediately after the restart by the first-out control has failed, the first-out control is prohibited. Therefore, when restarting again after a failure of restart, it is possible to avoid a problem that the pinion cannot be smoothly meshed with the ring gear, and thus it is possible to avoid significant wear damage of the ring gear or the pinion.

  The invention according to claim 6 is characterized in that, when the failure of the restart is detected by the detecting means, the advance control is performed after the engine speed becomes zero. On the other hand, in the invention according to claim 7, when the failure of the restart is detected by the detecting means, the restart is performed on the condition that the start operation is performed by the driver after the failure detection. It is characterized by doing.

  In short, as a countermeasure after a failure in restart, the invention according to claim 5 automatically restarts after the engine speed becomes zero. The engine restart request can be satisfied by performing the start. However, in this case, since the time lag from when the restart request is generated until the second restart is performed becomes longer, there is a concern that the driver may feel uncomfortable. In response to this concern, in the invention according to claim 7 described above, since the driver does not automatically restart unless the driver performs the starting operation, the uncomfortable feeling can be avoided.

  By the way, the above-mentioned autonomous return control, advance control and advance control are controls when a restart request is generated during the engine rotation descent period, but when a restart request is generated when the engine rotation is stopped. In the same manner as in the advance control, the pinion is pushed out and meshed with the ring gear, and then the pinion is rotated and restarted. Hereinafter, restart by this method is referred to as “normal control”.

  Also, “preset control” that pushes out the pinion and engages with the ring gear prior to the occurrence of the restart request when the engine speed decreases to zero just before the engine speed drops to zero during the engine rotation descent period Are known. If this preset control is performed, it is only necessary to rotationally drive the pinion when a restart request occurs thereafter, so that the pinion pushing time required for normal control can be shortened and restarted.

  However, even if the normal control is performed, the meshing may fail due to the above-mentioned deterioration over time and the restart may fail. Even if preset control is performed, the meshing may fail due to the above-mentioned deterioration over time. Immediately after these meshing failures, it becomes difficult to grasp the engine speed or the motor speed of the starter. Therefore, if normal control or preset control is performed immediately after the failure, the pinion is smoothly meshed with the ring gear. There is concern about significant wear damage of the ring gear or pinion.

  In response to this concern, the invention according to claim 8 includes preset control means for performing the preset control described above, and further includes detection means for detecting that the meshing by the preset control has failed, and the detection means When the restart failure is detected, execution of the preset control is prohibited during a period from when the failure is detected until the engine rotation speed becomes zero.

  According to this, execution of the preset control is prohibited during an engine rotation descent period in which it is difficult to accurately grasp the engine rotation speed and the starter motor rotation speed immediately after the meshing by the preset control has failed. Therefore, it is possible to avoid problems such as “the ring gear or the pinion is worn and damaged because the pinion cannot be smoothly meshed with the ring gear by trying the preset control again after the meshing failure by the preset control”.

  By the way, in the invention according to any one of claims 2 to 7, when the engine restart request is generated during the engine rotation lowering period in which the engine rotation speed decreases due to the automatic engine stop, Although the present invention is a coping method, the invention described in claim 1 is not limited to such a coping method, and includes, for example, a coping method when the restart by the normal control described above fails. That is, for example, immediately after the failure of the normal control restart, and during the engine rotation descent period in which it is difficult to accurately grasp the engine rotation speed and the motor rotation speed of the starter, the restart by the normal control or the like is performed. Accordingly, when the restart is attempted again after the restart failure, it is possible to avoid a problem that the pinion cannot be smoothly meshed with the ring gear, and thus it is possible to avoid a significant wear damage of the ring gear or the pinion.

1 is a schematic configuration diagram of an engine start control system to which an engine automatic stop start control device according to a first embodiment of the present invention is applied. The time chart explaining the engine restart control concerning 1st Embodiment. The time chart explaining advance control concerning 1st Embodiment. A time chart explaining advance control concerning a 1st embodiment. The flowchart explaining the process of the engine restart control routine concerning 1st Embodiment. The time chart which shows a mode that an engine speed falls, pulsating, after autonomous return control fails. The flowchart explaining the process of the restart control routine at the time of failure concerning 1st Embodiment. The flowchart explaining the process of the control routine at the time of the preset failure concerning 1st Embodiment. The flowchart explaining the process of the restart control routine at the time of failure concerning 2nd Embodiment of this invention.

  Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. The hardware configuration of the second embodiment is the same as that of the first embodiment shown in FIG.

(First embodiment)
First, a schematic configuration of the engine start control system will be described with reference to FIG.

  The starter 11 is a so-called pinion push-out starter, and includes a motor 12, a pinion 13 that is rotationally driven by the motor 12, an electromagnetic actuator 14 that pushes the pinion 13, and the like. The pinion 13 is provided so as to be movable in the axial direction. The electromagnetic actuator 14 is provided with a plunger 15 and a solenoid 16 for driving the plunger 15, and the driving force of the plunger 15 is transmitted to the pinion 13 through the lever 17 and the like.

  Further, a relay 19 is provided between the battery 18 and the electromagnetic actuator 14, and the ECU 15 (engine control circuit) turns on the relay 19 to turn on the electromagnetic actuator 14, thereby pushing the plunger 15 in the pinion pushing direction. Then, the pinion 13 is pushed out and meshed with a ring gear 23 connected to the crankshaft 22 of the engine 21.

  Further, a mechanical relay 25 and a switching element 24 for turning on / off the relay 25 are provided between the battery 18 and the motor 12. The switching element 24 is turned on by the ECU 20 to turn on the relay 25. By doing so, the energization of the motor 12 is turned on to drive the pinion 13 to rotate.

  The ECU 20 is mainly composed of a microcomputer, and executes various engine control programs stored in a built-in ROM (storage medium), thereby determining the fuel injection amount and ignition timing of the engine 21 according to the engine operating state. Control.

  Further, the ECU 20 executes engine automatic stop / start control (so-called idle stop control) by executing an engine automatic stop / start control routine (not shown). In this engine automatic stop start control, when the driver performs a deceleration operation (accelerator fully closed, brake operation, etc.) while the vehicle is running and a deceleration request is generated, or when the vehicle is stopped, an engine automatic stop request is issued. It is determined that it has occurred, and combustion (fuel injection and / or ignition) of the engine 21 is stopped, and the engine 21 is automatically stopped. After that, when the deceleration request is canceled while the vehicle is running, or while the vehicle is stopped, the driver performs a preparation operation for starting the vehicle (brake release, shift lever operation, etc.) or a start operation (accelerator depression, etc.). When it is determined that an engine restart request has occurred, the engine 21 is restarted.

  At this time, in this embodiment, the engine 20 is restarted as follows by executing an engine restart control routine of FIG.

  As shown in the time chart of FIG. 2, when an engine automatic stop request is generated during engine operation, combustion of the engine 21 is stopped and the engine 21 is automatically stopped.

<Autonomous return control>
An engine restart request is made in a first rotational speed region in which the engine rotational speed Ne is higher than the first rotational speed N1 (for example, 500 rpm) during the engine rotational speed decrease period in which the engine rotational speed Ne decreases due to the automatic stop of the engine 21. When this occurs, it is determined that the engine 21 can be restarted without performing cranking by the starter 11, and autonomous return control is executed. In this autonomous return control, the engine 21 is restarted by restarting fuel injection and ignition without performing cranking by the starter 11.

  Thereby, when the engine restart request | requirement generate | occur | produces, the combustion of the engine 21 can be restarted immediately and the engine 21 can be restarted rapidly. In addition, since the cranking by the starter 11 is not performed, the power consumption of the starter 11 can be reduced to zero, and the pinion 13 is meshed with the ring gear 23 in a state where the difference in rotational speed between the pinion 13 and the ring gear 23 is large. Can be avoided and generation of noise can be prevented.

<Previous control>
During the engine rotation descent period due to the automatic stop of the engine 21, an engine restart request is made in a second rotation speed region where the engine rotation speed Ne is equal to or lower than the first rotation speed N1 and higher than the second rotation speed N2 (for example, 250 rpm). Since the rotational speed of the ring gear 23 is relatively high, the pinion 13 cannot be smoothly meshed with the ring gear 23 unless the rotational speed of the pinion 13 is synchronized with the rotational speed of the ring gear 23. Execute the forward control. In this advance control, the rotational speed of the pinion 13 is synchronized with the rotational speed of the ring gear 23 by the motor 12 to reduce the difference between the rotational speeds of the two, and then the pinion 13 is engaged with the ring gear 23 by the electromagnetic actuator 14. Cranking is started and the engine 21 is restarted.

  Specifically, as shown in FIG. 3, at time t <b> 1 when an engine restart request is generated when the engine rotation speed Ne is in the second rotation speed region, the motor 12 is turned on and the motor 12 rotates the pinion 13. It is determined that the rotational speed of the pinion 13 is synchronized with the rotational speed of the ring gear 23 at a time t2 when the rotational speed difference between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 is within a range of ± 200 rpm. The energization of the electromagnetic actuator 14 is turned on, the pinion 13 is engaged with the ring gear 23, cranking by the starter 11 is started, and the engine 21 is restarted. Here, the “rotational speed difference” in the rotational speed difference between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 means a “rotational speed difference converted to the crankshaft 22” (hereinafter the same).

  In this way, the delay from the engine restart request to the restart of the engine 21 can be reduced while the pinion 13 is smoothly meshed with the ring gear 23 to prevent the generation of noise. Moreover, since it is not necessary to increase the detection accuracy of the rotation speed when determining the synchronization between the rotation speed of the ring gear 23 and the rotation speed of the pinion 13, for example, an expensive crank that can detect the rotation speed of the ring gear 23 with high accuracy. There is no need to provide an expensive rotation speed sensor that can accurately detect the rotation speed of the angle sensor or the pinion 13, and the demand for cost reduction, which is an important technical problem in recent years, can be satisfied.

  In the present embodiment, the diameter of the ring gear 23 (the outer diameter of the tooth tip) is 300 mm, and the diameter of the pinion 13 (the outer diameter of the tooth tip) is 30 mm. In this case, for example, when the rotational speed of the ring gear 23 is 300 rpm and the rotational speed of the pinion 13 is 1000 rpm, the rotational speed difference between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 (the rotational speed converted to the crankshaft 22). Difference) is 200 rpm. At this time, since the diameter of the ring gear 23 is 300 mm and the rotation speed is 300 rpm, the peripheral speed on the pitch circle of the ring gear 23 (on the imaginary circle where the pinion 13 is in contact with the gear) is about 4.7 m / sec. . Further, since the pinion 13 has a diameter of 30 mm and a rotational speed of 1000 rpm, the peripheral speed on the pitch circle of the pinion 13 (on the imaginary circle in contact with the ring gear 23) is about 1.6 m / sec. Thereby, the circumferential speed difference between the circumferential speed on the pitch circle of the ring gear 23 and the circumferential speed on the pitch circle of the pinion 13 is about 3.1 m / sec. Therefore, the difference in rotational speed between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 is within a range of ± 200 rpm. The peripheral speed between the peripheral speed on the pitch circle of the ring gear 23 and the peripheral speed on the pitch circle of the pinion 13. The speed difference is within a range of ± 3.1 m / sec.

  The present inventors conducted a test to measure the sound pressure when the pinion 13 and the ring gear 23 mesh. From this test result, when the rotational speed difference between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 is within a range of ± 250 rpm, the rotational speed difference between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 is preferably ± In the case of 200 rpm (that is, the peripheral speed difference between the peripheral speed on the pitch circle of the ring gear 23 and the peripheral speed on the pitch circle of the pinion 13 is within a range of ± 3.1 m / sec), the pinion 13 and the ring gear 23 It was confirmed that the sound pressure at the time of meshing can be sufficiently reduced.

  In the case of a system provided with a one-way clutch that transmits power to the starter 11 from the motor 12 to the pinion 13 in the engine rotation direction but does not transmit power from the pinion 13 to the motor 12, When the rotational speed of the ring gear 23 is higher than the rotational speed of the pinion 13 and the rotational speed difference between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 becomes a predetermined value (for example, 200 rpm) or less, the rotational speed of the pinion 13 May be determined to be synchronized with the rotational speed of the ring gear 23. Here, when the rotational speed difference between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 is 200 rpm or less, the peripheral speed difference between the peripheral speed on the pitch circle of the ring gear 23 and the peripheral speed on the pitch circle of the pinion 13. Is 3.1 m / sec or less.

  In this way, when it is determined that the rotation speed of the pinion 13 is synchronized with the rotation speed of the ring gear 23 and the pinion 13 is engaged with the ring gear 23, the rotation speed of the ring gear 23 is higher than the rotation speed of the pinion 13. The pinion 13 is meshed with the ring gear 23, but the one-way clutch is idled and the impact applied to the starter 11 can be mitigated. Thereafter, the engine rotational speed (rotational speed of the ring gear 23) decreases due to friction and the motor 12 rotates. When the rotational speed difference between the rotational speed of the ring gear 23 and the rotational speed of the pinion 13 becomes 0 as the speed (the rotational speed of the pinion 13) increases, the one-way clutch is locked and the motor 12 shifts to the pinion 13. Power begins to be transmitted. With such a behavior, the pinion 13 can be meshed with the ring gear 23 relatively smoothly, the impact on the components of the starter 11 is small, and a sufficient margin can be provided.

<First-out control>
When the engine restart request is generated in the third rotation speed region where the engine rotation speed Ne is equal to or lower than the second rotation speed N2 during the engine rotation drop period due to the automatic stop of the engine 21, the rotation speed of the ring gear 23 is relatively low. Since it is low, it is determined that the pinion 13 can be smoothly meshed with the ring gear 23 without synchronizing the rotation speed of the pinion 13 with the rotation speed of the ring gear 23, and the advance control is executed. In this advance control, after the pinion 13 is engaged with the ring gear 23 by the electromagnetic actuator 14 or during the engagement, the pinion 13 is rotated by the motor 12 to start cranking by the starter 11 and restart the engine 21. .

  Specifically, as shown in FIG. 4, at the time t3 when an engine restart request is generated when the engine rotational speed Ne is in the third rotational speed region, the energization of the electromagnetic actuator 14 is turned on and the pinion 13 is moved to the ring gear 23. At the time t4 when the meshing between the pinion 13 and the ring gear 23 is completed, or at the middle of the meshing, the motor 12 is energized and the motor 12 rotates the pinion 13 to start cranking by the starter 11 Then, the engine 21 is restarted.

  In this way, the process of synchronizing the rotation speed of the pinion 13 with the rotation speed of the ring gear 23 can be omitted while smoothly engaging the pinion 13 with the ring gear 23 to prevent the generation of noise. The start of cranking by the starter 11 can be accelerated to restart the engine 21 quickly, and the power consumption of the starter 11 can be reduced.

  In the restart control of the engine 21, the engine rotational speed Ne (the rotational speed of the ring gear 23) is, for example, an engine whose parameter is the elapsed time from the generation of the engine automatic stop request (or the combustion stop of the engine 21). With reference to the map of the rotational speed Ne, the engine rotational speed Ne corresponding to the elapsed time from the generation of the engine automatic stop request (or the combustion stop of the engine 21) is estimated (calculated). The map of the engine rotation speed Ne is created in advance based on test data, design data, and the like, and is stored in the ROM of the ECU 20. Generally, since the engine rotation speed Ne decreases with the lapse of time after the engine automatic stop request is generated and the combustion of the engine 21 is stopped, the engine automatic stop request is generated (or the engine 21 combustion is stopped). The engine speed Ne can be estimated from the elapsed time.

  The rotation speed of the pinion 13 is determined by referring to a map of the rotation speed of the pinion 13 with the energization time (elapsed time after the start of energization) and the energization current (for example, duty ratio) of the motor 12 as parameters. The rotational speed of the pinion 13 is estimated (calculated) according to the energization time and the energization current. A map of the rotational speed of the pinion 13 is created in advance based on test data, design data, and the like, and is stored in the ROM of the ECU 20. In general, with the passage of time after the start of energization of the motor 12, the rotation speed of the motor 12 increases and the rotation speed of the pinion 13 increases. At this time, the greater the energization current of the motor 12, the faster the rotation speed of the motor 12 becomes. Thus, the rotation speed of the pinion 13 is increased, and therefore the rotation speed of the pinion 13 can be estimated from the energization time and the energization current of the motor 12.

<Preset control>
Even when the engine restart request is not generated during the engine rotation drop period due to the automatic stop of the engine 21, when the engine rotation speed Ne decreases to the third rotation speed N3 (N3 ≦ N2), the preset is performed. Execute control. In this preset control, when the engine rotational speed Ne decreases to the third rotational speed N3, the pinion 13 is engaged with the ring gear 23 by the electromagnetic actuator 14, and then when the engine restart request is generated, the motor 12 Thus, the pinion 13 is rotated, cranking by the starter 11 is started, and the engine 21 is restarted.

  In this way, when the restart request is subsequently generated, it is only necessary to rotationally drive the pinion 13. Therefore, the pinion 13 is pushed out compared to the case where the pinion 13 is extruded after the restart request is generated and then rotated. Can be shortened. Therefore, the engine 21 can be restarted promptly.

  Further, by executing the preset control, the pinion 13 is moved to the ring gear before the engine swing period (a period in which reverse rotation and forward rotation of the engine 21 are alternately repeated (see FIG. 2)) just before the engine rotation is stopped. 23 can be engaged. Therefore, it is possible to prevent the pinion 13 from meshing with the ring gear 23 during the engine swinging period, and to prevent the starter 11 from being damaged or generating noise. Then, when an engine restart request is generated after the engine rotational speed Ne has dropped below the third rotational speed N3, cranking by the starter 11 is started and the engine 21 is restarted promptly at that time. Can do.

  The restart control of the engine 21 of the present embodiment described above is executed by the ECU 20 according to the engine restart control routine of FIG. Hereinafter, the processing content of the engine restart control routine of FIG. 5 will be described.

  The engine restart control routine shown in FIG. 5 is repeatedly executed at a predetermined cycle while the ECU 20 is powered on. When this routine is started, first, in step S101, it is determined whether or not automatic engine stop control is being performed (for example, a period from when combustion of the engine 21 is stopped until restart control is started). If it is determined that the stop control is not being performed, this routine is terminated without performing the process related to the restart control after step S103.

  On the other hand, if it is determined in step S101 that the engine automatic stop control is being performed, the process proceeds to step S102, where it is determined whether or not the engine rotational speed Ne is higher than a third rotational speed N3 (for example, 100 rpm). To do. If it is determined in step S102 that the engine rotational speed Ne is higher than the third rotational speed N3, the process proceeds to step S103, where it is determined whether an engine restart request has occurred, and an engine restart request is made. When it is determined that the engine rotation speed Ne has occurred, the process proceeds to step S104, and whether or not the engine rotation speed Ne is in the first rotation speed region depends on whether or not the engine rotation speed Ne is higher than the first rotation speed N1. Determine.

  Here, the first rotation speed N1 is set, for example, within a range of 300 to 700 rpm (500 rpm in the present embodiment). If the engine rotation speed Ne is higher than the first rotation speed N1 (300 to 700 rpm) during the engine rotation descent period, combustion (fuel injection / ignition) is simply resumed without cranking by the starter 11. Since the engine 21 can be restarted, if the first rotational speed N1 is set within the range of 300 to 700 rpm, the first rotational speed region higher than the first rotational speed N1 (300 to 700 rpm) is This is a region in which the fuel injection and ignition can be restarted and the engine 21 can be restarted without cranking.

  If it is determined in step S104 that the engine rotational speed Ne is higher than the first rotational speed N1 (that is, if the engine rotational speed Ne is in the first rotational speed region and an engine restart request is generated), It is determined that the engine 21 can be restarted without performing cranking by the starter 11, and the process proceeds to step S105 (autonomous return control means) to execute autonomous return control. In this autonomous return control, the engine 21 is restarted by restarting fuel injection and ignition without performing cranking by the starter 11.

  Thereafter, the process proceeds to step S106, where it is determined whether or not the engine 21 has been started, for example, depending on whether or not the engine speed Ne has exceeded a start completion determination value Nth (see FIG. 6). If it is determined that it has not been completed, the process returns to step S104, and if the engine rotational speed Ne is in the first rotational speed region, the autonomous return control is continued (steps S104 and 104). Thereafter, if it is determined in step S106 that the engine 21 has been started, this routine is terminated.

  On the other hand, if it is determined in step S104 that the engine rotational speed Ne is equal to or lower than the first rotational speed N1, the process proceeds to step S107, and whether or not the engine rotational speed Ne is higher than the second rotational speed N2. Thus, it is determined whether the engine rotational speed Ne is in the second rotational speed region or the third rotational speed region.

  Here, the second rotation speed N2 is set, for example, within a range of 50 to 450 rpm (250 rpm in the present embodiment). If the engine rotation speed Ne decreases to the second rotation speed N2 (50 to 450 rpm) or less during the engine rotation drop period, the pinion 13 can be moved without synchronizing the rotation speed of the pinion 13 with the rotation speed of the ring gear 23. Since the second gear can be smoothly meshed with the ring gear 23, if the second rotational speed is set within the range of 50 to 450 rpm, the third rotational speed region below the second rotational speed N2 (50 to 450 rpm) Even if the rotational speed of the pinion 13 is not synchronized with the rotational speed of the ring gear 23, this is an area where the pinion 13 can be smoothly meshed with the ring gear 23.

  If it is determined in step S107 that the engine rotational speed Ne is higher than the second rotational speed N2 (that is, if an engine restart request is generated in the second rotational speed region), Since the rotational speed of the ring gear 23 is relatively high, it is determined that the pinion 13 cannot be meshed smoothly with the ring gear 23 unless the rotational speed of the pinion 13 is synchronized with the rotational speed of the ring gear 23, and step S108 (advanced) Proceed to the control means) and execute the forward control.

  In this advance control, the elapsed time from the generation of the engine automatic stop request to the synchronization is calculated based on the map of the engine rotation speed Ne and the rotation speed map of the pinion 13 described above. Then, the pinion 13 is rotated by the motor 12 at the time when the engine automatic stop request is generated, and the pinion 13 is driven to be engaged with the ring gear 23 by the electromagnetic actuator 14 when the elapsed time is reached. As a result, the rotational speed of the pinion 13 is synchronized with the rotational speed of the ring gear 23 by the motor 12 to reduce the difference between the rotational speeds of the two and then the pinion 13 is meshed with the ring gear 23 by the electromagnetic actuator 14 and cranked by the starter 11. And the engine 21 is restarted.

  Thereafter, the process proceeds to step S109, where it is determined whether or not the engine 21 has been started. If it is determined that the engine 21 has been started, this routine is terminated, but the engine 21 has been started. If it is determined that there is not, the process proceeds to step S110 (first-out control means).

  On the other hand, when it is determined in step S107 that the engine rotational speed Ne is equal to or lower than the second rotational speed N2 (that is, when an engine restart request is generated in the third rotational speed range). Since the rotational speed of the ring gear 23 is relatively low, it is determined that the pinion 13 can be smoothly meshed with the ring gear 23 without synchronizing the rotational speed of the pinion 13 with the rotational speed of the ring gear 23. Proceeding to S110, first-out control is executed. In this advance control, the electromagnetic actuator 14 drives the pinion 13 to engage with the ring gear 23 at the time when the engine automatic stop request is generated. Then, after the meshing or during the meshing, the motor 12 rotates the pinion 13 to start cranking by the starter 11 and restart the engine 21.

  Thereafter, the process proceeds to step S111, where it is determined whether or not the engine 21 has been started. If it is determined that the engine 21 has not been started, the process returns to step S110 and the advance control is continued. . Thereafter, if it is determined in step S111 that the engine 21 has been started, this routine is terminated.

  If it is determined in step S102 that the engine rotational speed Ne is equal to or lower than the third rotational speed N3 (that is, the engine rotational speed Ne is equal to or lower than the third rotational speed N3 without generating an engine restart request). If it has decreased, the process proceeds to step S112 (preset control means) to execute preset control. In this preset control, when the engine rotational speed Ne decreases to the third rotational speed N3, the pinion 13 is engaged with the ring gear 23 by the electromagnetic actuator 14, and then when the engine restart request is generated, the motor 12 Thus, the pinion 13 is rotated, cranking by the starter 11 is started, and the engine 21 is restarted.

  In the process of FIG. 5 described above, in short, when an engine restart request is generated during the engine rotation descent period due to the automatic stop of the engine 21, the engine rotation speed Ne at the time of generation may be within the first rotation speed region. If it is the second rotation speed region, the advance control is executed, and if it is the third rotation speed region, the advance control is executed. If there is no engine restart request during the engine rotation descent period, preset control is executed.

  Therefore, when an engine restart request is generated during the engine rotation descent period, it is possible to perform appropriate engine restart control in accordance with the engine rotation speed Ne at that time. Generation | occurrence | production can be prevented and the power consumption of the starter 11 can be reduced.

  Further, in the process of FIG. 5, the engine rotation speed is estimated based on the elapsed time from the generation of the engine automatic stop request (or the combustion stop of the engine 21) during the engine restart control. Since it is not necessary to provide an expensive crank angle sensor that can accurately detect the engine speed during the engine speed drop period, the rotation speed of the pinion 13 is estimated based on the energization time and the energization current of the motor 12. The sensor for detecting the rotational speed of the motor 12 (the rotational speed of the pinion 13) can be omitted, and the demand for cost reduction, which is an important technical problem in recent years, can be satisfied.

  However, the problem described below is concerned only by performing the processing of FIG. That is, even if the above-described autonomous return control is performed, the engine restart may fail without performing desired combustion. In particular, if the autonomous return control is performed when the descending speed of the engine rotation speed Ne is high, the risk of failure increases. When such a failure of the autonomous return control occurs, according to the process of FIG. 5, the advance control is performed as the engine rotational speed Ne drops to the second rotational speed region.

  However, as shown in FIG. 6, the engine speed Ne after the automatic stop strictly decreases while repeatedly pulsating and rising. Therefore, when the autonomous return control is performed when the engine rotational speed Ne is in the first rotational speed range but the engine restart fails, the engine rotational speed Ne is set to the second rotational speed range after the failed time t10. When the advance control is performed at the time t20 when the engine is lowered to the point, the engine rotation speed Ne may be higher than the second rotation speed region at the time t30 when the pinion 13 is pushed out by the advance control. In this case, since the pinion 13 is pushed out in a state where the rotational speed of the ring gear 23 is much higher than the rotational speed of the pinion 13 (a state in which both rotational speeds are not synchronized), the pinion 13 smoothly contacts the ring gear 23. I can't bite. Therefore, there is a concern about significant wear damage of the ring gear 23 and the pinion 13.

  In addition, in the forward control, the advance control, and the preset control, it may fail to engage the pinion 13 with the ring gear 23 in some cases. The behavior of the engine rotation speed Ne immediately after the meshing failure is difficult to predict, and it is also difficult to grasp the motor rotation speed because the motor 12 of the starter 11 is also rotated by inertia. If the motor 12 is in a stationary state, the rotational speed of the motor 12 can be easily grasped based on the elapsed time since the energization of the motor 12 is started.

  Therefore, when the advance control is performed in the engine rotation drop period after the meshing failure due to the advance control or the inertial rotation period of the motor 12 after the mesh failure, both rotational speeds are required for performing the advance control. Are extremely difficult to synchronize.

  Further, in the case where the advance control is performed during the engine rotation lowering period after the meshing failure due to the advance control or the advance control or the inertial rotation period of the motor 12 after the meshing failure, the pinion 13 is used in the second rotation region. There is a concern that it may be driven out.

  Further, when the preset control is performed during the engine rotation drop period after the meshing failure by the preset control or the inertial rotation period of the motor 12 after the meshing failure, the rotation speed of the ring gear 23 and the rotation speed of the pinion 13 are There is a concern that the pinion 13 may be pushed and driven in a state where the difference is large.

  For these problems, in this embodiment, when engine restart by autonomous return control fails, or when meshing by advance control or advance control fails, from the time when the failure is detected, Thereafter, during the period until the engine speed Ne becomes zero, the autonomous return control, the advance control, and the advance control are prohibited, and the advance control is performed when the engine speed becomes zero.

  Further, when the meshing by the preset control fails, the execution of the preset control is prohibited from the time when the failure is detected until the engine rotation speed Ne becomes zero thereafter.

  The failure restart control described above is executed by the ECU 20 according to the failure restart control routine of FIG. The processing contents of the failure restart control routine of FIG. 7 will be described below. The process of FIG. 7 is a process for when the autonomous return control, the advance control, and the advance control fail, and the process for the preset control failure is executed according to another control routine described later.

  The failure restart control routine shown in FIG. 7 is repeatedly executed at a predetermined cycle while the ECU 20 is powered on.

  When this routine is started, first, in step S201 (detection means), it is determined whether or not restart by any one of the autonomous return control, the advance control, and the advance control has failed. For example, when the predetermined time elapses after the start of the autonomous return control, the predetermined time elapses after the start of the advance control, or the predetermined time elapses after the advance control starts, the engine rotation speed Ne is determined to be complete. When the value Nth (see FIG. 6) is not exceeded, it is determined that the restart has failed. When it is determined as failure, the time when the predetermined time has elapsed corresponds to “failure detection time”.

  If it is not determined to be unsuccessful, this routine is terminated without performing the process related to the restart control after step S202. On the other hand, if it is determined in step S201 that the restart has failed, the process proceeds to step S202, and it is determined whether or not the engine speed Ne has decreased to zero after detection of the failure. In this determination, it may be determined whether Ne = 0 using the detection signal of the crank angle sensor that detects the crank angle, or a sufficient predetermined time (for example, 3 seconds) has elapsed from the point of failure detection. It may be determined that Ne = 0 at the time.

  If it is determined that Ne is not 0, the process proceeds to step S203, and the execution of the autonomous return control in step S105, the forward control in step S108, and the advance control in step S110 is prohibited. If it is determined that Ne = 0, the process proceeds to step S204, and the first-out control similar to S110 in FIG. 5 is executed. Specifically, when it is determined that Ne = 0, the electromagnetic actuator 14 is energized and pushed out to engage the pinion 13 with the ring gear 23.

  Thereafter, the process proceeds to step S205, where it is determined whether or not the engine 21 has been started. If it is determined that the engine 21 has not been started, the process returns to step S204 to continue the advance control. . Thereafter, if it is determined in step S205 that the engine 21 has been started, this routine is terminated. It should be determined that the start of the engine 21 has been completed when the engine speed Ne has increased beyond the start completion determination value Nth between the execution of the advance control and the elapse of a predetermined time.

  Next, a process for failure of preset control performed separately from the process of FIG. 7 will be described with reference to FIG.

  The preset failure control routine shown in FIG. 8 is repeatedly executed at a predetermined cycle while the ECU 20 is powered on.

  When this routine is started, first, in step S201a (detection means), it is determined whether or not meshing (preset) by the preset control has failed. For example, a sensor for detecting the push-out position of the pinion 13 is provided, and whether or not the pinion 13 is pushed to a predetermined position and meshed with the ring gear 23 based on the detection value of the sensor (preset state). Can be determined.

  If it is not determined to be unsuccessful, this routine is terminated without performing the processing from step S202a. On the other hand, if it is determined in step S201a that the preset has failed, the process proceeds to step S202a, and it is determined whether or not the engine speed Ne has decreased to zero after detection of the failure. In this determination, it is only necessary to determine whether Ne = 0 using a detection signal of a crank angle sensor that detects a crank angle.

  If it is determined that Ne = 0 is not satisfied, the process proceeds to step S203a, and execution of the preset control in step S112 of FIG. 5 is prohibited. If it is determined that Ne = 0, the process proceeds to step S204a, and the same preset control as in step S112 in FIG. 5 is attempted again. Specifically, when it is determined that Ne = 0, the electromagnetic actuator 14 is energized and pushed out to engage the pinion 13 with the ring gear 23.

  As described above, according to the present embodiment, it is prohibited to perform these controls immediately after the restart by the autonomous return control, the advance control, and the advance control fails. Therefore, when restarting again after a restart failure, it is possible to avoid the problem that the pinion 13 cannot be meshed smoothly with the ring gear 23, and consequently, significant wear damage of the ring gear 23 and the pinion 13 can be avoided. Further, it is possible to avoid a problem that the autonomous return control fails again immediately after the autonomous return control fails.

  Furthermore, according to this embodiment, after the engine rotational speed Ne becomes zero, the restart by the advance control is automatically performed. Therefore, even if the restart fails once, the restart is automatically performed again. The engine restart request can be satisfied.

  Immediately after the meshing by the preset control fails, the retry of the preset control is prohibited. Therefore, the pinion 13 cannot be smoothly meshed with the ring gear 23 when the preset control is retried. The trouble that the pinion 13 is worn and damaged can be avoided.

(Second Embodiment)
In the first embodiment, as a countermeasure after the failure of restart, restart by the advance control is automatically performed when the engine rotation speed Ne becomes zero. On the other hand, in this embodiment, when the restart fails, the automatic restart is prohibited even after the engine rotational speed Ne becomes zero. Then, after the engine rotational speed Ne becomes zero, the restart is performed on the condition that the start operation is performed by the driver of the vehicle on which the engine 21 is mounted.

  The restart control upon failure according to the present embodiment is executed by the ECU 20 according to the engine restart control routine of FIG. The processing contents of the failure restart control routine of FIG. 9 will be described below.

  The failure restart control routine shown in FIG. 9 is repeatedly executed at predetermined intervals while the ECU 20 is powered on. In addition, in FIG. 9, about the process to which the same code | symbol as FIG. 7 was attached | subjected, since it is the same as the process of FIG. 7, description is used.

  When this routine is started, first, in step S201 (detection means), it is determined whether or not restart by any one of the autonomous return control, the advance control, and the advance control has failed. If it is not determined to be unsuccessful, this routine is terminated without performing the process related to the restart control after step S202. On the other hand, if it is determined in step S201 that the restart has failed, the process proceeds to step S202, and it is determined whether or not the engine speed Ne has decreased to zero after detection of the failure.

  If it is determined that Ne = 0 is not satisfied, the process proceeds to step S203, and execution of the autonomous return control, the forward control, and the advance control is prohibited. If it is determined that Ne = 0, the process proceeds to step S206 and waits without performing restart until the vehicle driver performs a starting operation. Note that, when it is detected that the ignition switch has been switched from OFF to ON, it may be determined that the starting operation has been performed by the driver.

  In step S207, if it is determined that the starting operation has been performed by the driver, the process proceeds to step S208, and advance control similar to S110 in FIG. 5 is executed. Specifically, when it is determined that Ne = 0, the electromagnetic actuator 14 is energized and pushed out to engage the pinion 13 with the ring gear 23.

  Thereafter, the process proceeds to step S209, where it is determined whether or not the engine 21 has been started. If it is determined that the engine 21 has not been started, the process returns to step S208 to continue the advance control. . Thereafter, if it is determined in step S209 that the engine 21 has been started, this routine is terminated.

  As described above, according to the present embodiment, it is prohibited to perform these controls immediately after the restart by the autonomous return control, the advance control, and the advance control fails. Further, it is possible to avoid a problem that the pinion 13 cannot be smoothly meshed with the ring gear 23, and it is possible to avoid a problem that the autonomous return control fails again immediately after the autonomous return control fails.

  Here, in the case of the first embodiment in which the restart is automatically performed when Ne = 0 after the restart failure, the time lag from when the restart request is generated until the second restart is performed. Because of this, there is a concern that the driver may feel uncomfortable. In response to this concern, according to the present embodiment, even after the engine rotational speed Ne has become zero, until the driver performs a start operation, the execution of the restart by the advance control is prohibited and waits. A sense of incongruity can be avoided.

(Other embodiments)
The present invention is not limited to the description of the above embodiment, and may be modified as follows. Moreover, you may make it combine the characteristic structure of each embodiment arbitrarily, respectively.

  In the first embodiment, when an engine restart request is generated during the engine rotation descent period, if the engine rotation speed Ne at the time of generation is the first rotation speed region, autonomous return control is executed, The present invention is applied to a system in which advance control is executed in the second rotational speed region and advance control is executed in the third rotational speed region. On the other hand, the advancing control is abolished, and if the engine speed Ne at the time when the restart request is generated is in the second rotational speed region, it waits for the engine speed to fall to the third rotational speed region, and the first-out control The present invention may be applied to a system that executes control.

  -Alternatively, the autonomous return control is abolished, and if the engine speed Ne at the time when the restart request is generated is the first rotational speed region, the process waits until the engine speed Ne drops to the second rotational speed region. The present invention may be applied to a system that executes control.

  -Alternatively, if the autonomous return control and the advance control are abolished and the engine speed Ne at the time when the restart request is generated is the first rotational speed region or the second rotational speed region, the first rotational speed The present invention may be applied to a system in which advance control is executed after waiting for a drop to a region.

  As described above, in the determination in step S202 of FIG. 7, it may be determined that Ne = 0 when a sufficient predetermined time (for example, 3 seconds) has elapsed since the failure detection time. However, since the viscosity of the engine oil increases as the engine temperature decreases, the driving friction of the engine 21 increases. Therefore, after the restart fails, the decrease speed of the engine rotation speed Ne increases. In view of this point, it is desirable to set the predetermined time shorter as the engine temperature (for example, engine coolant temperature) is lower. According to this, after restart failure, the restart timing can be made as early as possible by the advance control in step S204.

  ・ The above-mentioned autonomous return control, advance control and advance control are controls when a restart request occurs during the engine rotation descent period, but when a restart request occurs when the engine rotation is stopped In the same manner as in the advance control, after the pinion 13 is pushed out and meshed with the ring gear 23, the normal control is performed such that the pinion 13 is rotated and restarted. When restarting by such normal control is performed, the restart may fail due to failure in normal combustion, for example, due to reasons such as failure of normal ignition or failure of normal fuel injection. Whether or not such a failure has occurred is detected based on whether or not the engine rotational speed Ne has reached a predetermined value after a predetermined time has elapsed since the restart was performed. If a restart failure is detected, the failure is detected. You may make it prohibit implementation of the said normal control from the time until the engine speed Ne becomes zero.

  According to this, immediately after the restart due to the normal control fails, during the engine rotation descent period in which it is difficult to accurately grasp the engine rotation speed Ne and the motor rotation speed of the starter 11, the normal control or the like restarts. Since starting is prohibited, it is possible to avoid a problem that the pinion 13 cannot be smoothly meshed with the ring gear 23 when attempting to restart again after a failure of restarting. As a result, significant wear damage of the ring gear 23 or the pinion 13 is caused. Can be avoided.

  DESCRIPTION OF SYMBOLS 11 ... Starter, 12 ... Motor, 13 ... Pinion, 14 ... Electromagnetic actuator (actuator), S105 ... Autonomous return control means, S108 ... Advance control means, S110 ... Advance control means, S112 ... Preset control means, S201, S201a ... Detection means.

Claims (8)

A starter that can individually operate a motor that rotationally drives the pinion and an actuator that meshes the pinion with a ring gear that is connected to the crankshaft of the engine, and automatically stops the engine when an engine automatic stop request occurs, In the engine automatic stop / start control device for restarting the engine when an engine restart request is generated,
Detecting means for detecting that the restart has failed;
When the failure of the restart is detected by the detection means, the engine automatic stop start is prohibited from being performed during the period from the failure detection time until the engine speed becomes zero. Control device. When the engine restart request is generated in a first rotation speed region in which the engine rotation speed is higher than the first rotation speed during an engine rotation drop period in which the engine rotation speed decreases due to the automatic stop of the engine, Autonomous return control means for performing autonomous return control to restart fuel injection by restarting fuel injection without performing cranking by the starter;
When the engine restart request is generated in a second rotation speed region in which the engine rotation speed is equal to or lower than the first rotation speed and higher than the second rotation speed during the engine rotation drop period, After synchronizing the rotation speed of the pinion with the rotation speed of the ring gear, the actuator engages the pinion with the ring gear and starts cranking by the starter to restart the engine. Control means;
The pinion is engaged with the ring gear by the actuator when the engine restart request is generated in the third rotation speed region where the engine rotation speed is equal to or lower than the second rotation speed during the engine rotation drop period. A first-out control means for performing first-out control for rotating the pinion by the motor after the start or during the meshing thereof to start cranking by the starter and restarting the engine;
With
The detection means detects that the restart by any of the autonomous return control, the advance control and the advance control has failed,
When the restart failure is detected by the detection means, the autonomous return control, the advance control and the advance control are performed during the period from the failure detection time until the engine rotation speed becomes zero. The engine automatic stop / start control device according to claim 1, wherein the engine automatic stop / start control device is prohibited. When the engine restart request is generated in a first rotation speed region in which the engine rotation speed is higher than the first rotation speed during an engine rotation drop period in which the engine rotation speed decreases due to the automatic stop of the engine, Autonomous return control means for performing autonomous return control to restart fuel injection by restarting fuel injection without performing cranking by the starter;
When the engine restart request is generated in the third rotation speed region where the engine rotation speed is equal to or lower than the first rotation speed during the engine rotation drop period, the pinion is engaged with the ring gear by the actuator. A first-out control means for performing first-out control for rotating the pinion by the motor after the start or during the meshing thereof to start cranking by the starter and restarting the engine;
With
The detecting means detects that the restart by either the autonomous return control or the advance control has failed,
When the restart failure is detected by the detecting means, the autonomous return control and the advance control are prohibited during the period from the failure detection time until the engine rotation speed becomes zero. The engine automatic stop / start control device according to claim 1. When the engine restart request is generated in a second rotation speed region in which the engine rotation speed is higher than the second rotation speed during an engine rotation decrease period in which the engine rotation speed decreases due to the automatic stop of the engine, After the rotation speed of the pinion is synchronized with the rotation speed of the ring gear by the motor, forward control is performed in which the actuator engages the pinion with the ring gear, starts cranking by the starter, and restarts the engine. Advance control means to implement;
The pinion is engaged with the ring gear by the actuator when the engine restart request is generated in the third rotation speed region where the engine rotation speed is equal to or lower than the second rotation speed during the engine rotation drop period. A first-out control means for performing first-out control for rotating the pinion by the motor after the start or during the meshing thereof to start cranking by the starter and restarting the engine;
With
The detection means is for detecting that the restart by either the advance control or the advance control has failed,
When the restart failure is detected by the detecting means, the advance control and the advance control are prohibited during the period from the failure detection time until the engine rotation speed becomes zero. The engine automatic stop / start control device according to claim 1. When the engine restart request is generated in the third engine speed range during the engine speed decrease period during which the engine speed decreases due to the automatic stop of the engine, the pinion is moved by the actuator to the ring gear. A first-out control means for performing first-out control for rotating the pinion by the motor to start cranking by the starter and restarting the engine after or during the engagement.
The detection means detects that the restart by the advance control has failed,
2. If the restart failure is detected by the detecting means, the advance control is prohibited during a period from when the failure is detected until the engine rotation speed becomes zero. The engine automatic stop / start control device according to 1.   The restart is performed again after the engine rotation speed becomes zero when the detection means detects the restart failure. 6. The engine automatic stop / start control device according to 1.   2. When the restart failure is detected by the detecting means, the restart is performed again on the condition that a start operation is performed by the driver after the failure detection. The engine automatic stop / start control device according to any one of? 5. A starter that can individually operate a motor that rotationally drives the pinion and an actuator that meshes the pinion with a ring gear that is connected to the crankshaft of the engine, and automatically stops the engine when an engine automatic stop request occurs, In the engine automatic stop / start control device for restarting the engine when an engine restart request is generated,
When the engine rotation speed decreases to a predetermined rotation speed immediately before the engine rotation speed becomes zero during the engine rotation speed decrease period during which the engine rotation speed decreases due to the automatic engine stop, the actuator restarts the engine prior to the generation of the engine restart request. Preset control means for performing preset control for engaging a pinion with the ring gear;
Detecting means for detecting that the meshing by the preset control has failed;
With
When the failure of the restart is detected by the detection means, the automatic engine stop is prohibited from performing the preset control for a period from when the failure is detected until the engine rotation speed becomes zero. Start control device.

Images