JP2011226400A - Starter driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve engine start in an abnormal off-state of a driving relay by adding the lowest number of parts.SOLUTION: The starter driving device includes a pinion driving relay RLp provided to a first path for supplying power to a pinion driving part 12 and a motor driving relay RLm provided to a second path for supplying power to a motor 13. A relay RLf for failure is also provided to a third path that links an intermediate point between the pinion driving relay RLp and the pinion driving part 12 with an intermediate point between the motor driving relay RLm and the motor 13. When an occurrence of an abnormal off-state in which either one of the pinion driving relay RLp or the motor driving relay RLm cannot be turned on and remains in an off-state is detected, cranking is performed using the relay RLf for failure.

Description

  The present invention relates to a starter driving device.

  2. Description of the Related Art Conventionally, there is known an engine control system having a so-called idle stop function that detects an operation for stopping or starting such as an accelerator operation or a brake operation to automatically stop and restart an engine. By this idle stop control, effects such as engine fuel consumption reduction are achieved.

  When the engine is restarted, an initial rotation is first applied to the output shaft (crankshaft) of the engine by a starter, basically as in the case of engine start by key operation. Specifically, first, the starter pinion is pushed out in the axial direction of the rotating shaft by energization control, and the pinion is engaged with the ring gear connected to the crankshaft. After the meshing, the pinion is rotated by energizing the starter motor. Thereby, cranking is started and the engine is restarted. In addition, as a starter used for engine restart, the drive circuit for pinion extrusion and the drive circuit for motor rotation (pinion rotation) can be configured separately, and pinion extrusion and rotation can be controlled individually. Is known (for example, see Patent Document 1).

Japanese Patent No. 4214401

  In a configuration in which a drive circuit for pinion extrusion and a drive circuit for pinion rotation are separately provided, when only one of the respective drive circuits malfunctions (off failure), the other operates normally. Even in this case, it is conceivable that the engine cannot be restarted. On the other hand, in order to cope with such a partial failure, a redundant circuit is provided for each drive circuit, and a normal circuit operation is maintained by switching the defective circuit portion to the redundant circuit. Can be considered. However, in this case, since redundant circuits are provided for the respective drive circuits, the number of circuits to be added increases, and as a result, there are concerns that problems such as system complexity and cost increase may occur.

  The present invention has been made to solve the above-described problems, and can start an engine even when a drive relay OFF abnormality occurs, and minimizes engine start at the time of the abnormality. The main object is to provide a starter driving device that can be realized by adding the number of parts.

  The present invention employs the following means in order to solve the above problems.

  The present invention is applied to a starter including a pinion that meshes with a ring gear of an engine, a pinion drive unit that drives the pinion from a non-engagement state with the ring gear to a meshing state, and a motor that rotates the pinion, and the pinion drive A first drive relay provided on a first path for supplying power to the motor and a second drive relay provided on a second path for supplying power to the motor, and cranking the engine by power supply through each of the drive relays. It is related with the starter drive device which performs. The invention according to claim 1 is provided in a third path connecting an intermediate point between the first drive relay and the pinion drive unit and an intermediate point between the second drive relay and the motor. An abnormality detecting means for detecting an occurrence of an off abnormality that cannot be turned on and remains in an off state in any of the first drive relay and the second drive relay; And an abnormality start control means for performing the cranking using the third drive relay when it is detected by the abnormality detection means that the off abnormality has occurred.

  In the above configuration, by switching the third drive relay disposed on the third path to the ON state, at the intermediate point between the first drive relay and the pinion drive unit and the intermediate point between the second drive relay and the motor. The first path and the second path are conducted. Therefore, even when the first drive relay is in the OFF state, power can be supplied to the pinion drive unit via the second drive relay and the third drive relay. Similarly, power can be supplied to the motor via the first drive relay and the third drive relay even when the second drive relay is in the OFF state. Therefore, according to the above configuration, no off abnormality has occurred even in the case where an off abnormality has occurred that remains in the off state without being turned on in either the first drive relay or the second drive relay. By using the third drive relay while also serving as the other relay, power can be supplied to the pinion drive unit and the motor, so that the pinion and the ring gear can be engaged and the motor can be rotated. That is, it is not necessary to provide a redundant circuit for each of the first path and the second path. Therefore, it is possible to cope with the off abnormality of the first drive relay and the second drive relay while suppressing the occurrence of inconveniences such as the complexity of the system and the increase in cost due to the increase in the number of parts.

  In the state where the first drive relay or the second drive relay is off, the engine start using the third drive relay is different from the normal starter drive, and is the normal drive relay of the first drive relay and the second drive relay. It is conceivable that the current flowing through (the drive relay that is not off-normal) becomes larger than normal. Therefore, it is desirable to minimize its implementation.

  In that respect, the invention described in claim 2 further includes an allowable number of times setting means for setting an allowable number of times of starting using the third drive relay by the abnormal time start control means. Thereby, implementation of the starter drive using the third drive relay can be restricted. The allowable number of times setting means may be set to a predetermined number of times (for example, once) or may be set to be variable.

  The invention according to claim 3 has an automatic stop start function for automatically stopping the engine when a predetermined automatic stop condition is satisfied and then restarting the engine when a predetermined restart condition is satisfied. The abnormality start control means performs the cranking using the third drive relay when the occurrence of the off abnormality is detected during the restart. When the engine is restarted by so-called idle stop control, for example, when a vehicle waiting for a signal is started, it is conceivable that there is a high need for reliably starting the engine. Therefore, it is preferable to start the engine using the third drive relay when an off abnormality of the drive relay is detected when the engine is restarted by the idle stop control.

  As a configuration for restricting the starter drive using the third drive relay, the cranking using the third drive relay is performed by the abnormality start control means as in the invention according to claim 4. In such a case, automatic stop restriction means for restricting execution of the automatic stop thereafter may be provided. According to this configuration, when the starter drive using the third drive relay is performed, the number of times of the starter drive using the third drive relay can be reduced by limiting the subsequent automatic engine stop.

  When cranking the engine with a starter, from the viewpoint of suppressing pinion and ring gear wear and meshing noise, the pinion is engaged with the ring gear and then the motor is rotated (initial rotation is applied to the engine output shaft). Is desirable. In view of this point, in the invention according to claim 5, when it is detected by the abnormality detection means that an off abnormality of the second drive relay has occurred, an on-switching timing of the first drive relay is determined. At a later timing, the third drive relay is switched to the on state to perform the cranking. By doing so, it is possible to supply power to the pinion drive unit before the motor, and as a result, the motor can be driven after the pinion and the ring gear are engaged. Therefore, when the engine is cranked by the starter, it is possible to suitably suppress the wear of the pinion and the ring gear and the meshing sound.

  The invention according to claim 6 further comprises operation detecting means for detecting that the engine start switch has been operated by a driver, wherein the abnormality start control means is configured to detect that the off abnormality has occurred by the abnormality detecting means. The cranking using the third drive relay is permitted on the condition that the operation detection means detects that the start switch has been operated after it is detected that the operation is detected. In view of the fact that engine start using a third drive relay is different from normal starter drive, it is desirable to minimize its implementation. In that respect, according to the above configuration, the starter drive using the third drive relay can be performed when it is certain that the driver has an intention to restart the engine. As a result, in the situation where the driver wants to restart the engine, the starter reliably starts the engine, but in the situation where the intention to restart the engine is not confirmed (when the start switch is not operated), the start by the third drive relay is not performed. Can be. Thereby, suppression of engine starting by the third drive relay can be suitably performed while reflecting the driver's intention.

  In a seventh aspect of the invention, a delay circuit that delays the drive timing of the motor is provided between the second drive relay, the third drive relay, and the motor.

  In normal times (when the relay is normal), for example, the motor drive timing can be delayed from the meshing timing between the pinion and the ring gear by controlling the relay ON switching timing, but no abnormality has occurred when the relay is abnormal Since the other relay is also used, it is considered that the above delay control cannot be performed. In that respect, as in the above configuration, a delay circuit is arranged between the second drive relay and the motor and between the third drive relay and the motor, so that the drive timing of the motor is delayed by the delay circuit. Can be made. Therefore, the motor can be rotated at a timing later than the timing at which the pinion and the ring gear are engaged with each other, so that the wear of the pinion and the like and the engagement noise can be suppressed.

The electrical block diagram which shows the whole engine control system outline. The figure explaining starter drive control at the time of normal. The figure explaining starter drive control at the time of OFF failure occurrence. The flowchart which shows the process sequence of OFF failure handling. The time chart which shows the specific aspect of the starter drive control at the time of normal. The time chart which shows the specific aspect of starter drive control at the time of OFF failure generation | occurrence | production. The electrical block diagram which shows the whole schematic of the engine control system of other embodiment. The electrical block diagram which shows the whole schematic of the engine control system of other embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. This embodiment is embodied in an engine stop / start control device of an engine control system. In the control system, fuel injection amount control, ignition timing control, idle stop control, and the like are performed with an electronic control unit (hereinafter referred to as ECU) as a center. FIG. 1 shows an electrical configuration diagram showing an overall outline of the control system.

  In FIG. 1, a starter 10 is a pinion extrusion type starter, and includes a pinion 11, a pinion drive unit 12 that is an actuator that pushes or releases the pinion 11, and a motor 13 that rotates the pinion 11.

  The pinion drive unit 12 and the motor 13 are each connected to the battery BAT by wiring. A pinion drive relay RLp that switches between energization / non-energization of the pinion drive unit 12 is provided in the first path between the battery BAT and the pinion drive unit 12. A motor drive relay RLm that switches between energization / non-energization of the motor 13 is provided in the second path between the battery BAT and the motor 13.

  The pinion drive relay RLp and the motor drive relay RLm each have a relay switch and a relay coil. In the pinion drive relay RLp, the relay switch is provided in the first path. When the relay coil is excited, the relay switch is turned on (that is, the pinion drive relay RLp is turned on), and power is supplied to the pinion drive unit 12. Done. Further, in the motor drive relay RLm, the relay switch is provided in the second path. When the relay coil is excited, the relay switch is turned on (that is, the motor drive relay RLm is turned on), and power is supplied to the motor 13. Done.

  When the pinion drive unit 12 is energized from the battery BAT, the pinion 11 is pushed in the axial direction by the energization, and meshed with a ring gear (not shown) provided on the engine side. Further, in the meshed state of the pinion 11 and the ring gear, the motor 13 is rotated by energizing the motor 13 from the battery BAT, and the pinion 11 rotates as the motor 13 rotates. Thereby, cranking is performed and initial rotation is given to the engine.

  Further, in this system, the first route and the second route are connected by the wiring 14, and a third relay (hereinafter referred to as a failure response relay RLf) is arranged on the third route connected by the wiring 14. ing. The third path is provided as a path connecting an intermediate point between the pinion drive relay RLp and the pinion drive unit and an intermediate point between the motor drive relay RLm and the motor 13. The failure handling relay RLf includes a relay switch and a relay coil. In the failure handling relay RLf, the relay switch is provided on the third path. When the relay coil is excited, the relay switch is turned on (that is, the failure handling relay RLf is turned on), and the first path and the second path are connected. Conducted. That is, it is possible to switch between conduction / cutoff between the first path and the second path by switching on / off the failure handling relay RLf.

  In addition, this system includes a starter switch (ST switch) 15 that can be switched on / off based on a driver's key operation, and an ignition switch (IG switch) 23 as an engine start switch operated by the driver. A switch, a voltage sensor 16 provided at an intermediate point between the pinion drive relay RLp and the pinion drive unit 12 and detecting an output voltage Vp of the pinion drive relay RLp, and provided at an intermediate point between the motor drive relay RLm and the motor 13. A voltage sensor 17 that detects an output voltage Vm of the motor drive relay RLm, a crank angle sensor 18 that outputs a rectangular crank angle signal for each predetermined crank angle of the engine, an accelerator sensor 19 that detects the amount of depression of an accelerator pedal, and a brake A brake that detects the amount of pedal depression Various sensors such as a sensor 21 is provided.

  The ECU 30 is an electronic control device including a known microcomputer 31 or the like, and inputs detection results of various sensors provided in the system, and based on the input, intake air amount control and fuel injection amount Various engine controls such as control and idle stop control, and drive control of the starter 10 are performed.

  The idle stop control performed in the above system configuration will be described. In the idle stop control, the engine is automatically stopped when a predetermined stop condition is satisfied during the idling operation of the engine, and thereafter, the engine is restarted when a predetermined restart condition is satisfied. The engine stop condition includes, for example, at least one of the fact that the accelerator operation amount has become zero (becomes in an idle state), and that the brake pedal has been depressed. Further, the engine restart condition includes, for example, that the accelerator is depressed, the brake operation amount is zero, and the like.

  Next, drive control of the starter 10 will be described in detail. In this system, the ECU 30 includes a first switching element TR1, a second switching element TR2, and a third switching element TR3. The first switching element TR1 is connected to the relay coil of the pinion drive relay RLp via the output port P1, and the second switching element TR2 is connected to the relay coil of the motor drive relay RLm via the output port P2. The third switching element TR3 is connected to the relay coil of the failure handling relay RLf via the output port P3. Thereby, in this system, it is possible to individually switch on / off of the first switching element TR1, the second switching element TR2, and the third switching element TR3. Accordingly, by outputting an ON signal to each of the first switching element TR1 and the second switching element TR2 at a desired timing, the push-out of the pinion 11 (meshing the pinion 11 and the ring gear) and the motor 13 are performed. Rotation can be controlled individually. Further, by outputting an ON signal to the third switching element TR3 at a desired timing, the conduction / cutoff between the first path and the second path can be switched at the desired timing.

  Specifically, for example, when the starter switch 15 is switched from OFF to ON or when the engine is started when the restart condition is satisfied after the engine is automatically stopped, the microcomputer 31 first switches the first switching element TR1 to ON. The pinion drive relay RLp is switched on. In this case, as shown in FIG. 2, electric power is supplied to the pinion drive unit 12 through the first path Rp1, and the pinion 11 is pushed out toward the ring gear.

  Subsequently, the microcomputer 31 switches on the second switching element TR2 and switches on the motor drive relay RLm. In this case, as shown in FIG. 2, electric power is supplied to the motor 13 through the second path Rm1, the motor 13 is rotated, the pinion 11 is rotated, and the engine is cranked. In FIG. 2, the third switching element TR3 is not turned on, and the failure handling relay RLf remains off.

  However, when an abnormality (off failure) occurs in which the contact of the pinion drive relay RLp or the motor drive relay RLm does not switch to the on state while the contact is off, the energization of the pinion drive unit 12 by the route Rm1 or the motor 13 by the route Rp1 occurs. It becomes impossible to carry out energization. On the other hand, if either of the pinion drive unit 12 and the motor 13 is not energized, the starter 10 cannot start the engine even if the other drive relay can operate normally. In particular, the restart after the engine has been automatically stopped is often in a situation where, for example, a vehicle waiting for a signal is started. In such a case, when the engine cannot be restarted, there is a concern of causing a road fault.

  In view of this point, in the present system, when an off-failure occurs in either the pinion drive relay RLp or the motor drive relay RLm, the engine is cranked using the failure response relay RLf. That is, power is supplied to the actuator on the side where the failure has occurred via the failure handling relay RLf, thereby supplying power to the pinion drive unit 12 and the motor 13.

  Specifically, if an off-failure has occurred in either the pinion drive relay RLp or the motor drive relay RLm when a restart request is made after the engine has been automatically stopped, a drive signal is sent to the third switching element TR3. The third switching element TR3 is switched from off to on. As a result, when an off failure occurs in the motor drive relay RLm, as shown in FIG. 3A, power is supplied to the pinion drive unit 12 via the route Rp1 via the pinion drive relay RLp, and the pinion drive relay RLp and the failure are detected. Electric power is supplied to the motor 13 through the route Rm2 via the corresponding relay RLf. Further, when an off-failure of the pinion drive relay RLp occurs, as shown in FIG. 3B, electric power is supplied to the pinion drive unit 12 via the route Rp2 via the motor drive relay RLm and the failure handling relay RLf to drive the motor. Electric power is supplied to the motor 13 through a route Rm1 via the relay RLm. As described above, in this system, even when an off failure occurs in either the pinion drive relay RLp or the motor drive relay RLm, the pinion 11 can be pushed out and the motor 13 can be reliably rotated. Yes.

  In the starter drive, the second switching element TR2 is switched on at a timing later than the first switching element TR1 for the following reason. That is, when the cranking of the engine by the starter 10 is performed, from the viewpoint of suppressing wear of the pinion 11 and the ring gear and suppressing the meshing sound at the time of meshing, the rotation of the motor 13 is performed after the pinion 11 is meshed with the ring gear. It is desirable to rotate the pinion 11 by. On the other hand, the time (motor operation delay time) from when the first switching element TR1 is switched on until the motor 13 is actually started is relatively short, for example, about 10 msec, whereas the second switching element The time from when TR2 is switched to the ON state until the pinion 11 is actually engaged with the ring gear (engagement required time) is, for example, about 30 msec, which is longer than the motor operation delay time. Therefore, in the present embodiment, in consideration of the difference between the motor operation delay time and the meshing required time, the ON switching timing of the second switching element TR2 is delayed from the first switching element TR1, thereby driving the motor 13 to be driven. Is performed after the meshing timing of the pinion 11 and the ring gear.

  Next, a processing procedure for handling a failure when an off-failure of the drive relays RLp and RLm occurs will be described with reference to the flowchart of FIG. This process is executed at predetermined intervals by the microcomputer 31 of the ECU 30.

  In FIG. 4, first, in step S100, it is determined whether or not a value 0 is set in the pinion drive relay circuit abnormality flag Fp and the motor drive relay circuit abnormality flag Fm. Here, the pinion drive relay circuit abnormality flag Fp is a flag indicating whether or not an off-fault has occurred in the pinion drive relay RLp. The value is 0 if it is normal, and is set to 1 in the off-fault occurrence state. Is done. The motor drive relay circuit abnormality flag Fm is a flag indicating whether or not an off failure has occurred in the motor drive relay RLm. The flag is 0 if it is normal, and is set to 1 if an off failure has occurred. The In step S100, the process proceeds to step S101 on condition that Fp = 0 and F = 0.

  In step S101, it is determined whether or not an engine restart condition has been satisfied (whether a restart request has been made) after the engine has been automatically stopped. If there is a restart request after the engine is automatically stopped, the process proceeds to step S102, and the first switching element TR1 is switched to the ON state in order to drive the pinion 11.

  In a succeeding step S103, it is determined whether or not the pinion drive relay RLp is operating normally. In the present embodiment, is the output voltage Vp detected by the voltage sensor 16 greater than the determination value after the time required for meshing between the pinion 11 and the ring gear has elapsed from the on timing of the first switching element TR1? Determine whether or not. When the output voltage Vp is larger than the determination value, the process proceeds to step S104, and the second switching element TR2 is switched to the ON state in order to drive the motor 13.

  In step S105, it is determined whether or not the motor drive relay RLm is operating normally. In the present embodiment, it is determined whether or not the output voltage Vm detected by the voltage sensor 17 is greater than the determination value after the operation delay time of the motor 13 has elapsed from the ON timing of the second switching element TR2. If the output voltage Vm is greater than the determination value, the process proceeds to step S106, and it is determined whether the engine start is completed. Here, for example, it is determined whether or not the engine rotational speed has reached the starting rotational speed NEf (for example, 400 to 500 rpm).

  When an affirmative determination is made in step S106, the process proceeds to step S107, and the first switching element TR1 and the second switching element TR2 are switched to the off state. As a result, the meshing between the pinion 11 and the ring gear is released, the rotation drive of the motor 13 is stopped, and the cranking of the engine by the starter 10 is ended.

  Now, when an off failure of the pinion drive relay RLp occurs, the output voltage Vp does not exceed the determination value even after the time required for meshing has elapsed from the on switching timing of the first switching element TR1. Therefore, a negative determination is made in step S103, and the process proceeds to step S108. In step S108, the second switching element TR2 is switched to the on state, and the third switching element TR3 is switched to the on state. As a result, the motor drive relay RLm and the failure handling relay RLf are switched on. As a result, electric power is supplied to the motor 13 via the motor drive relay RLm, and electric power is supplied to the pinion drive unit 12 via the motor drive relay RLm and the failure handling relay RLf. Further, in step S108, a value 1 is set to the pinion drive relay circuit abnormality flag Fp, assuming that an off failure has occurred in the pinion drive relay RLp. Then, it progresses to step S110.

  On the other hand, when an off failure of the motor drive relay RLm occurs, the output voltage Vm does not exceed the determination value even after the motor operation delay time has elapsed from the on switching timing of the second switching element TR2. Therefore, a negative determination is made in step S105, and the process proceeds to step S109. In step S109, the third switching element TR3 is turned on. As a result, the failure handling relay RLf is switched on. As a result, electric power is supplied to the pinion drive unit 12 via the pinion drive relay RLp, and electric power is supplied to the motor 13 via the motor drive relay RLm and the failure handling relay RLf. In step S109, a value 1 is set to the motor drive relay circuit abnormality flag Fm on the assumption that an OFF failure has occurred in the motor drive relay RLm. Then, it progresses to step S110.

  In step S110, for example, it is determined whether or not the engine start has been completed based on the engine rotation speed. If it is determined that the engine start has been completed, the process proceeds to step S111. In step S111, the third switching element TR3 is switched to the off state, and the switching element on the side that is in the on state among the first switching element TR1 and the second switching element TR2 is switched to the off state. In addition, the user is notified of the content that prompts the vehicle inspection by means of a warning lamp, a warning display, a buzzer, a sound, or the like.

  Further, in step S111, a value 1 is set to the engine automatic stop prohibition flag Fs. The engine automatic stop prohibition flag Fs is a flag for prohibiting the automatic engine stop when the engine automatic stop condition is satisfied next after the engine is restarted by the current starter drive. In this embodiment, when the value 1 is set in the flag Fs, the subsequent automatic engine stop is prohibited.

  That is, as the engine automatic stop process, the microcomputer 31 determines whether or not the engine automatic stop condition is satisfied. When the engine automatic stop condition is satisfied, the microcomputer 31 determines whether or not a value 1 is set in the flag Fs. . When the value 1 is set in the flag Fs, automatic engine stop is prohibited. When the value 0 is set in the flag Fs, automatic engine stop is permitted.

  5 and 6 are time charts showing specific modes of the starter drive control. Among these, FIG. 5 shows a case where the pinion drive relay RLp and the motor drive relay RLm operate normally. In FIG. 6, (a) shows a case where an off failure of the pinion drive relay RLp occurs, and (b) shows a case where an off failure of the motor drive relay RLm occurs.

  As shown in FIG. 5, when the drive relays RLp and RLm are normal, if there is a restart request after the engine is automatically stopped, the first switching element TR1 is switched to the ON state at the timing t11. As a result, the output voltage Vp of the pinion drive relay RLp rises at the timing t12 and becomes larger than the determination value Vpth, and as a result of driving the pinion drive unit 12, the pinion 11 and the ring gear are engaged. Further, the second switching element TR2 is switched to the ON state at a timing t13 after the engagement required time TA has elapsed from the timing t11. As a result, the output voltage Vm of the motor drive relay RLm increases at the timing t14 and becomes larger than the determination value Vmth, and as a result of the motor 13 rotating, the ring gear is rotated by the pinion 11. Then, it is determined that the engine start has been completed at timing t15, and the first switching element TR1 and the second switching element TR2 are switched to the off state.

  On the other hand, when an off failure of the pinion drive relay RLp occurs, as shown in FIG. 6A, even after the first switching element TR1 is switched on at timing t21, the output of the pinion drive relay RLp. The voltage Vp does not increase and the state below the determination value Vpth is continued. Then, the second switching element TR2 is switched to the ON state at timing t22 after the meshing required time TA has elapsed from timing t21. In the present embodiment, this timing t22 is used as a determination timing for an off-fault of the pinion drive relay RLp. At this timing, it is determined that an off-fault of the pinion drive relay RLp has occurred, and a value 1 is set in the pinion drive relay circuit abnormality flag Fp. In addition, the third switching element TR3 is turned on. As a result, at the subsequent timing t23, the output voltage Vp of the pinion drive relay RLp and the output voltage Vm of the motor drive relay RLm become larger than the determination values, respectively, and the engagement of the pinion 11 and the ring gear and the rotation of the pinion 11 are performed. Is done. Then, it is determined that the engine start has been completed at timing t24, the second switching element TR2 and the third switching element TR3 are switched to the OFF state, and a value 1 is set to the engine automatic stop prohibition flag Fs.

  Next, consider a case where an OFF failure of the motor drive relay RLm occurs. In this case, as shown in FIG. 6B, since the pinion drive relay RLp is normal, the output voltage of the pinion drive relay RLp at timing t32 is obtained by switching the first switching element TR1 to the on state at timing t31. Vp rises. Then, the second switching element TR2 is switched to the ON state at a timing t33 after the meshing required time TA has elapsed from the timing t31. At this time, if an off failure of the motor drive relay RLm has occurred, the output voltage Vm of the motor drive relay RLm does not increase even if the second switching element TR2 is switched to the on state, and the state is equal to or less than the determination value Vmth Will continue. In the present embodiment, the timing t34 after the motor operation delay time TB has elapsed from the timing t33 is used as the determination timing for the OFF failure of the motor drive relay RLm, and it is determined that the OFF failure of the motor drive relay RLm has occurred at the same timing. The value 1 is set in the motor drive relay circuit abnormality flag Fm, and the third switching element TR3 is switched to the ON state. As a result, at the subsequent timing t35, the output voltage Vp of the pinion drive relay RLp and the output voltage Vm of the motor drive relay RLm become larger than the determination values, respectively, and the engagement of the pinion 11 and the ring gear and the rotation of the pinion 11 are performed. Is done.

  In the present embodiment, when the motor drive relay RLm is in an off-fault occurrence state, the meshing required time TA from the timing t31 is specifically the timing after the on-switching timing (t31) of the first switching element TR1. At the timing t34 after the lapse, the third switching element TR3 is switched to the on state. Thereby, the motor 13 is driven after the engagement between the pinion 11 and the ring gear is completed.

  Then, it is determined that the engine start is completed at timing t36, the first switching element TR1 and the third switching element TR3 are switched to the OFF state, and a value 1 is set to the engine automatic stop prohibition flag Fs.

  According to the embodiment described in detail above, the following excellent effects can be obtained.

  A failure handling relay RLf is provided on the third path connecting the intermediate point between the pinion drive relay RLp and the pinion drive unit 12 and the intermediate point between the motor drive relay RL and the motor 13 by the wiring 14, and the pinion drive relay RLp and When an off-failure has occurred in one of the motor-driven relays RLm, the engine is cranked using the failure-response relay RLf. Therefore, the other relay in which no off-failure has occurred is also used. Power can be supplied to the pinion drive unit 12 and the motor 13. As a result, even when the relay OFF failure occurs, the pinion 11 and the ring gear can be engaged and the motor 13 can be rotated. In this case, it is not necessary to provide a redundant circuit for each of the first path and the second path. Therefore, it is possible to cope with an off failure of the pinion drive relay RLp and the motor drive relay RLm while suppressing the occurrence of inconveniences such as a complicated system and an increase in cost due to an increase in the number of parts.

  When the engine is restarted, when the occurrence of an off-fault of the relays RLp, RLm is detected, the engine is started using the failure-response relay RLf. For example, when starting a vehicle waiting for a signal, etc. The engine restart can be reliably performed in a situation where it is highly necessary to reliably start the engine. Thereby, a road fault can be avoided.

  When the engine is started using the failure handling relay RLf, the construction of the automatic engine stop thereafter is limited, so that a road fault occurs while suppressing the start of the engine using the failure handling relay RLf. Can be suppressed.

  When it is detected that an off-fault of the motor drive relay RLm has occurred, the failure-corresponding relay RLf is turned on at a timing later than the on-switching timing of the pinion drive relay RLp. Since the failure response relay RLf is switched to the on state after the required engagement time TA has elapsed from the on switching timing of the pinion drive relay RLp, the motor 13 can be driven after the pinion 11 and the ring gear are engaged. Therefore, when the cranking of the engine is performed by the starter 10, it is possible to suitably suppress the wear of the pinion 11 and the ring gear and the meshing sound.

  Since the starter drive using the failure corresponding relay RLf is performed based on the off failure of the drive relays RLp and RLf detected at the time of the engine restart this time, the off failure of the drive relays RLp and RLf has surely occurred. In this situation, the starter driving can be performed. That is, when the engine restart is performed by the failure handling relay RLf based on the detection result before the current engine restart (for example, during engine operation before the engine automatic stop), the off-failure is temporarily When the engine is restarted (failure that can be recovered), the engine is operated by the failure handling relay RLf even though the failure has been resolved at the time of the current engine restart (the drive relays RLp and RLf operate normally). Start-up will be performed. In that respect, with the above-described configuration, it is possible to start the engine using the failure-response relay RLf when the drive relays RLp and RLf are in an off-failure state.

(Other embodiments)
The present invention is not limited to the description of the above embodiment, and may be implemented as follows, for example.

  -If any of the pinion drive relay RLp or motor drive relay RLm is detected to be off abnormally, the failure response relay RLf is turned on on the condition that it is detected that the driver has operated the IG switch 23 after the detection. Switch to state. The engine start using the failure handling relay RLf is different from the starter driving at the normal time, and considering that the current flowing through the pinion driving relay RLp and the motor driving relay RLm is larger than the normal time, the starter driving by the failure handling relay RLf is performed. It is desirable to minimize implementation. In that respect, if the IG switch 23 is operated, it is certain that the driver intends to restart the engine, and in such a case, the driver restarts the engine by performing the starter drive described above. In a situation where the start is truly desired, the starter driving using the failure handling relay RLf can be suppressed as much as possible while the engine is restarted by the starter.

  If the engine can be started by the pinion drive relay RLp and the motor drive relay RLm without using the failure corresponding relay RLf, if the pinion drive relay circuit abnormality flag Fp or the motor drive relay circuit abnormality flag Fm is 1, the flag Fp, The configuration is such that Fm is reset to 0 (the diagnosis is turned off). At this time, if the engine automatic stop prohibition flag Fs is also a value 1, it is desirable to reset it to a value 0. As an off-failure of the pinion drive relay RLp and the motor drive relay RLm, not only the one that cannot be restored but also one that can be restored (temporary) can be considered. In view of that point, the above configuration allows the pinion drive relay RLp and the motor drive relay RLm to return to normal operation even if it is determined that an off-failure has occurred once. The cranking of the engine by the starter 10 can be performed. Further, the prohibition of the engine automatic stop is canceled, and the idle stop function can be effectively utilized.

  In the above configuration, for example, the first switching element TR1 and the second switching element TR2 are each connected to the starter switch 15 by wiring, and the third switching element TR3 is not directly connected to the starter switch 15 via wiring. It can be preferably applied. In this case, when the starter switch 15 is turned on, the first switching element TR1 and the second switching element TR2 are turned on, and the pinion drive relay RLp and the motor drive relay RLm are turned on. Therefore, when the start of the engine can be completed by driving the starter 10 in accordance with the ON operation of the IG switch 23 by the driver, it can be determined that the pinion drive relay RLp and the motor drive relay RLm operate normally.

  A configuration including an allowable number setting means for setting an allowable number of starter drives using the failure handling relay RLf is adopted. In this case, it is possible to limit the starter driving using the failure handling relay RLf. Therefore, by appropriately determining the allowable number of times, it is possible to suppress the starter drive by the failure handling relay RLf as much as possible. Specifically, the allowable number of times is set to a predetermined number of times. For example, by setting the allowable number of times to one, the starter drive by the failure handling relay RLf is performed only for the first engine restart after the off-failure occurs. Alternatively, the allowable number of times may be variably set according to the engine operating state and the like each time.

  The delay circuit 22 is arranged between the microcomputer 31 and the second switching element TR2 (FIG. 7). In this case, the drive timing of the motor 13 can be delayed with respect to the meshing timing of the pinion 11 and the ring gear regardless of the control of the ON switching timing of the switching elements TR1 and TR2 (ON switching timing of the relays RLp and RLm). it can.

  The delay circuit 22 is arranged between the pinion drive relay RLp and failure response relay RLf and the motor 13 (FIG. 8). In normal times when the relays RLp and RLm normally operate, for example, the drive timing of the motor 13 can be delayed from the meshing timing of the pinion 11 and the ring gear by controlling the ON switching timing of the relays RLp and RLm. However, when an off-failure has occurred in either of the relays RLp and RLm, power is supplied to the pinion drive unit 12 and the motor 13 by using the relay that does not have the off-failure, so that the delay control described above is performed. It may be impossible to implement In that respect, the relays RLp and RLm are arranged by arranging the delay circuit 22 between the motor drive relay RLm and the motor 13 and between the failure response relay RLf and the motor 13 as in the configuration of FIG. Even in the off failure occurrence state, the drive timing of the motor 13 can be delayed by the delay circuit 22. Therefore, the motor can be rotated at a timing later than the timing at which the pinion 11 and the ring gear are engaged, and as a result, the wear of the pinion 11 and the like and the engagement noise can be suppressed.

  In the above embodiment, when the motor drive relay RLm is off, the failure response relay RLf is turned on at a timing later than the on-switching timing of the pinion drive relay RLp so that the meshing timing and the motor drive timing are different. Although it is set as the structure switched, it changes this and sets it as the structure which makes the coil inductance of failure response relay RLf and the coil inductance of motor drive relay RLm different.

  In the above embodiment, when an off failure of the pinion drive relay RLp or the motor drive relay RLm is detected, the engine automatic stop is prohibited by prohibiting the subsequent engine automatic stop, but this is changed. For example, when the starter drive is performed using the failure response relay RLf, the engine automatic stop is executed only after n times (for example, only once when the engine automatic stop condition is satisfied m times). To do.

  In the above embodiment, the configuration is such that the off failure of the drive relays RLp and RLm is detected by comparing the output voltages Vp and Vm with the determination value, but the detection method is not limited to the above as long as the off failure can be detected. . For example, the OFF failure of the motor drive relay RLm is detected by comparing the engine rotation speed with a determination value (for example, the starting rotation speed) or comparing the battery current with the determination value. This is because when the off-failure occurs, the engine speed increases due to cranking and the battery discharge due to motor energization becomes smaller than normal. At this time, an off-failure may be detected using two or more parameters.

  -Although applied to the engine which has an idle stop function, you may apply to the normal engine which does not have the same function. In this configuration, when the IG switch 23 and the ST switch 15 are turned on based on the operation of the driver, if any of the pinion drive relay RLp and the motor drive relay RLm has an off failure, the failure handling relay RLf is Use it to crank the engine.

  DESCRIPTION OF SYMBOLS 10 ... Starter, 11 ... Pinion, 12 ... Pinion drive part, 13 ... Motor, 22 ... Delay circuit, 30 ... ECU (Abnormality detection means, cranking means, permissible number setting means, automatic stop restriction means, operation detection means), 31 ... Microcomputer, BAT ... Battery, RLp ... Pinion drive relay (first drive relay), RLm ... Motor drive relay (second drive relay), RLf ... Fault response relay (third drive relay), TR1 ... First switching element , TR2 ... second switching element, TR3 ... third switching element.

Claims (7)

Applied to a starter comprising a pinion that meshes with a ring gear of an engine, a pinion drive unit that drives the pinion from a non-engagement state with the ring gear to a meshing state, and a motor that rotates the pinion,
A first drive relay provided on a first path for supplying power to the pinion drive unit; and a second drive relay provided on a second path for supplying power to the motor. In the starter drive device that performs cranking of
A third drive relay provided in a third path connecting an intermediate point between the first drive relay and the pinion drive unit and an intermediate point between the second drive relay and the motor;
An abnormality detection means for detecting that an off abnormality that cannot be turned on and remains in an off state occurs in any of the first drive relay and the second drive relay;
An abnormality start control means for performing the cranking using the third drive relay when it is detected by the abnormality detection means that the off abnormality has occurred;
A starter driving device comprising:   2. The starter driving device according to claim 1, further comprising an allowable number of times setting unit that sets an allowable number of times of starting using the third drive relay by the abnormality start control unit. Applied to an engine having an automatic stop start function for automatically stopping the engine when a predetermined automatic stop condition is satisfied, and then restarting the engine when a predetermined restart condition is satisfied;
3. The starter drive according to claim 1, wherein the abnormality start control unit performs the cranking using the third drive relay when the occurrence of the off abnormality is detected at the time of the restart. apparatus.   The starter drive device according to claim 3, further comprising an automatic stop restriction unit that restricts execution of the automatic stop thereafter when the cranking using the third drive relay is performed by the abnormality start control unit.   When the abnormality detection unit detects that the second drive relay is turned off, the abnormality start control unit detects the first drive relay at a timing later than the on-switch timing of the first drive relay. The starter driving device according to any one of claims 1 to 4, wherein the cranking is performed by switching a three-drive relay to an on state. An operation detecting means for detecting that the engine start switch is operated by a driver;
The abnormality start control means is provided on the condition that the operation detection means detects that the start switch is operated after the abnormality detection means detects that the off abnormality has occurred. The starter drive device according to any one of claims 1 to 5, wherein the cranking using a third drive relay is permitted.   The starter drive device according to any one of claims 1 to 6, further comprising a delay circuit that delays a drive timing of the motor between the second drive relay and the third drive relay and the motor.

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