JP5464163B2 - Starter control device - Google Patents

Description

  The present invention relates to a starter control device for cranking a vehicle engine (internal combustion engine) for starting.

  As a starter for starting the engine, when battery voltage (battery positive terminal voltage) is supplied to the other end of the solenoid coil, one end of which is connected to the ground line (battery negative terminal side), the coil is supplied to the coil. The pinion gear meshes with the ring gear of the engine due to the electromagnetic force generated by the energization of the motor, and the electromagnetic switch provided in the energization path to the motor that rotationally drives the pinion gear is turned on (that is, the contact is short-circuited). It is known that energization is performed (see, for example, Patent Document 1).

  In other words, in this type of starter, the energization of the solenoid coil causes the starter to function by engaging the pinion gear with the ring gear and energizing the motor to rotate the pinion gear (rotating the ring gear). Both of which are applied). In addition, making a starter function means making a starter crank an engine. In the electrical field, a solenoid coil may be referred to as a solenoid, but in this specification, it is called a mechatronics field, and a movable coil such as a coil or a plunger that operates by the electromagnetic force of the coil is used. The actuator including the part is called a solenoid.

  Therefore, in general, in an apparatus for controlling this type of starter, a starter relay as a switch provided between a coil of the solenoid provided in the starter and a battery voltage is turned on, and the above-described starter relay is connected to the starter relay. The starter is caused to function by passing a current through the coil of the solenoid (for example, see Patent Document 1).

  As another type of starter, a pinion gear that can be switched between a state in which it engages with the ring gear of the engine and a state in which it does not engage with the ring gear independently of energization / non-energization of the motor is also known. (For example, refer to Patent Document 2).

  More specifically, this type of starter is independently provided with a solenoid for moving the pinion gear to mesh with the ring gear, and an electromagnetic switch, which is a large relay provided in the energization path to the motor. In other words, a solenoid coil for moving the pinion gear and an electromagnetic switch coil for energizing the motor are provided separately. In addition, since this kind of starter can control a pinion gear and a motor independently separately, it is hereinafter referred to as an independent control type starter or simply as an independent control type.

  Therefore, in general, in an apparatus that controls an independent control type starter, a pinion drive relay as a switch provided in a current path from a battery voltage to the solenoid coil and a current path from the battery voltage to the coil of the electromagnetic switch. The starter functions by turning on each of the motor drive relays as the provided switches.

  On the other hand, Patent Document 2 discloses an engine automatic stop / start system (generally, an idle stop) that automatically stops an engine when a predetermined stop condition is satisfied, and then automatically starts the engine when a predetermined start condition is satisfied. (Or called an idling stop system) is also described. According to the above-described independent control type starter, for example, before the starter motor (starter motor) is operated, the pinion gear can be engaged with the ring gear of the engine, and wear of mechanical parts such as the pinion gear can be controlled. Therefore, it can be said that it is suitable for an idle stop vehicle in which the starter is used frequently.

JP 2001-207942 A Japanese Patent Laid-Open No. 11-30139

  In a control device that functions a starter by turning on the above-described starter relay (ie, a device that controls a starter that is not an independent control type), when an on-failure (failure that remains on) occurs in the starter relay The current continues to flow through the solenoid coil for causing the starter to function, and as a result, the pinion gear of the starter meshes with the ring gear and the motor remains in operation.

  Similarly, when an on-failure occurs in a pinion drive relay in a control device that functions a starter by turning on the pinion drive relay and the motor drive relay described above (that is, a device that controls an independent control starter). The current continues to flow through the solenoid coil for moving the pinion gear, and as a result, the pinion gear remains engaged with the ring gear. Further, when an on-failure occurs in the motor drive relay, the current remains flowing through the coil of the electromagnetic switch for operating the motor, and as a result, the motor remains in operation.

  In any case, both or one of the starter pinion gear and the motor is operated unnecessarily (that is, not at the time of engine start), and as a result, the deterioration thereof is accelerated. Absent.

  The present invention has been made in view of these problems, and a function of a starter corresponding to an electrical load caused by an on-failure occurring in a switch means provided in a current path for energizing an electrical load for causing the starter to function. An object of the present invention is to improve the reliability of the starter control device by preventing abnormalities in which parts are operated unnecessarily and making it possible to detect the possibility that such abnormalities are increasing.

In the vehicle in which the starter control device of the first invention is used, one end of the electric load for causing the starter to crank the engine for starting is one of the high potential side and the low potential side of the power source. Connected to the first potential.

  The starter control device includes a second potential that is different from the first potential on the high potential side and the low potential side of the power source, and the other end of the electric load (the side opposite to the first potential side). By turning on the energizing switch means provided in the current path between the current load and the current path, the current is passed through the electric load to cause the starter to function.

In particular, the starter control device according to the first aspect of the invention is turned on as non-load side switch means in which one terminal of the pair of terminals that are short-circuited by being turned on is connected to the second potential as the energizing switch means. One terminal of the pair of terminals that are short-circuited is connected to a terminal opposite to the second potential side of the non-load side switch means, and the other terminal is connected to the other end of the electric load. Load side switch means.

  That is, it is a current path between the second potential and the electrical load (specifically, the end of the electrical load opposite to the first potential side). Non-load side switch means and load side switch means in series are provided.

  Further, the starter control device includes an abnormality detection unit, and the abnormality detection unit is configured such that the non-load side switch unit and the load side switch unit are driven to turn off, Off-drive that monitors the voltage of the inter-switch path, which is the current path to the load-side switch means, and detects an on-failure of either the non-load-side switch means or the load-side switch means based on the voltage Anomaly detection processing is performed.

  Here, when the voltage of the inter-switch path when driving to turn off the non-load side switch means and the load side switch means is described as “Voff”, if the Voff is normal, However, when an on failure occurs in the load-side switch means, the path between the switches is connected to the first potential via the load-side switch means and the electric load, so Voff is the first potential. Fixed to potential. Conversely, when an on-failure occurs in the non-load side switch, the inter-switch path is connected to the second potential via the non-load side switch means, so that Voff is fixed to the second potential.

  For this reason, it is possible to detect an on-failure between the non-load side switch unit and the load side switch unit based on Voff. For example, in the off-drive abnormality detection process, it is determined whether Voff is either the first potential or the second potential, and if it is determined that Voff is the first potential, the load side If it is determined that the switch means is on-failed, and it is determined that Voff is at the second potential, it can be determined that the non-load side switch means is on-failed.

Incidentally, the first resistance component is provided between the first potential and the switch between paths, if providing the second resistance component between the second potential and the inter-switch route, Voff during normal, A power supply voltage (power supply voltage), which is the difference between the first potential and the second potential, is divided by the first resistance component and the second resistance component. Therefore, since the normal Voff can be surely set to a value different from the first potential and the second potential, whether or not Voff is either the first potential or the second potential. Judgment can be made easily and correctly. However, even if the first and second resistance components are not provided, for example, if Voff is continuously at the first potential for a predetermined time or more, Voff is really at the first potential. Similarly, if Voff is continuously at the second potential for a predetermined time or more, it can be determined that Voff is really at the second potential.

  According to such a starter control device, unless both the non-load side switch means and the load side switch means are on-failed, the electric load is unnecessarily energized via the energization switch means (hereinafter referred to as the electric load). To an unnecessary energization state or simply an unnecessary energization state). In other words, even if one of the non-load side switch means and the load side switch means is turned on, it can be prevented from becoming an unnecessary energized state unless the other is turned on. It is possible to prevent an abnormality (hereinafter referred to as an unnecessary operation abnormality of the starter or simply an abnormal operation abnormality) in which the functional part of the starter corresponding to the electric load operates unnecessarily. Note that the functional part of the starter corresponding to the electric load is a functional part of the starter that is operated by energizing the electric load.

  Furthermore, since the on-failure of either the non-load side switch means or the load side switch means can be detected by the abnormality detection means, an unnecessary energization state to the electric load (and hence an unnecessary operation abnormality of the starter) ) Is likely to occur, and some kind of treatment can be performed in advance.

  In other words, if one of the non-load side switch means and the load side switch means fails to turn on, it will not immediately reach the unnecessary energized state, but if the other also fails to turn on, the unnecessary energized state will result. It can be said that the possibility of occurrence of the unnecessary energized state (unnecessary operation abnormality) increases. Therefore, the reliability of the apparatus can be improved by performing some measures when an on-failure of one of the non-load side switch means and the load side switch means is detected.

Based on this, in the starter control device of the second invention, in the starter control device of the first invention , the vehicle stops the engine when a predetermined automatic stop condition is satisfied, and then the predetermined automatic start condition is satisfied. An idle stop control means for restarting the engine is provided, and the starter control device is configured to switch the energization switch means (that is, the non-load side switch means and the load) when the idle stop control means restarts the engine. The starter functions by turning on the side switch means. Further, the starter control device is configured to prevent the idle stop control means from stopping the engine when the abnormality detection means detects an on-failure of either the non-load side switch means or the load side switch means. It is forbidden.

According to this configuration, it is possible to prevent an unnecessary start abnormality of the starter.
In other words, even if one of the non-load side switch means and the load side switch means is on-failed, the normal switch means is turned on / off to control energization / non-energization of the electrical load (and thus the starter). However, when the normal switch means is turned on, there is a possibility that the switch means will be on-failed. As a result, unnecessary starter operation abnormalities will occur. Therefore, when an on-failure of either the non-load side switch means or the load side switch means is detected, the starter is caused to function by prohibiting idle stop (automatic engine stop by the idle stop control means). Opportunities that must be made (that is, opportunities to turn on the non-load side switch means and the load side switch means) are reduced, and even the normal switch means are prevented from being turned on.

Next, in the starter control device of the third invention, in the starter control devices of the first and second inventions , the abnormality detecting means is any one of the non-load side switch means and the load side switch means. The device is driven to turn on, and among the non-load side switch means and the load side switch means, except for the specific switch means, the voltage in the inter-switch path is monitored while being driven to turn off. Based on the voltage, an on-drive abnormality detection process for detecting an off-fault of the specific switch means (a fault that remains off without being turned on) is performed.

  Here, an inter-switch path when driving so that only the load-side switch means is turned on among the non-load-side switch means and the load-side switch means (that is, when the load-side switch means is the specific switch means). Is described as “Von1”, and the voltage of the inter-switch path when driven so that only the non-load side switch means is turned on (that is, when the non-load side switch means is the specific switch means) is , “Von2”, if normal, Von1 is fixed at the first potential and Von2 is fixed at the second potential. However, when an off failure occurs in the load side switch means, Von1 is not fixed at the first potential, and when an off failure occurs in the non-load side switch means, Von2 is not fixed at the second potential.

For this reason, an off-fault of the load side switch means can be detected based on Von1, and an off-fault of the non-load side switch means can be detected based on Von2.
For example, in the on-drive abnormality detection process using the load-side switch means as a specific switch, if it is determined that Von1 is a voltage that is neither the first potential nor the second potential based on Von1, It can be determined that the load-side switch means has an off failure. Similarly, in the on-drive abnormality detection process using the non-load side switch means as a specific switch, if it is determined that Von2 is a voltage that is neither the first potential nor the second potential based on Von2. In this case, it can be determined that the non-load side switch means has an off failure.

Incidentally, the first resistance component is provided between the first potential and the switch between paths, if providing the second resistance component between the second potential and the inter-switch route, load side switching means off Von1 in the case of failure and Von2 in the case where the non-load side switch means is in failure is a value obtained by dividing the power supply voltage by the first resistance component and the second resistance component. Therefore, it is possible to easily and correctly determine whether Von1 or Von2 is a voltage that is neither the first potential nor the second potential. However, even if such first and second resistance components are not provided, for example, if Von1 and Von2 continue for a predetermined time or longer and are not at either the first potential or the second potential, Von1 , Von2 can be determined to be a voltage that is neither the first potential nor the second potential.

According to such a starter control device of the third aspect of the invention , it is possible to detect an off failure of the specific switch means that is one of the non-load side switch means and the load side switch means.

  And when the off failure of the specific switch is detected, it means that the specific switch means cannot be turned on, and the starter cannot function, so that it is not necessary to function the starter. It is preferable to take some measures to do this. For example, as the treatment, a process for prompting the driver of the vehicle not to stop the engine can be considered. This is because it is not necessary to make the starter function unless the engine is stopped. As a process for prompting the driver not to stop the engine, for example, a process of outputting a message indicating that the engine should not be stopped with a sound or displaying it on a display device can be considered. Also, for example, if the vehicle stops the engine when a predetermined push-type switch is continuously pressed, a process for changing the validity determination time from when the switch starts to being pressed until the engine is stopped to a time longer than the normal value. But it ’s okay.

In the starter control device according to the fourth aspect of the present invention, the abnormality detection means detects each of the non-load side switch means and the load side switch means in order to detect each of the non-load side switch means and the load side switch means. Examples particular switch means, intends row the oN drive abnormality detection processing. For this reason, each of the non-load side switch means and the load side switch means can detect an off failure, and the reliability of the starter control device can be further improved.

Next, in the starter control device of the fifth invention, in the starter control device of the third and fourth inventions , the abnormality detection means is any of the non-load side switch means and the load side switch means by the off-drive abnormality detection process. When such an on-failure is detected, the on-drive abnormality detection process is not performed. In other words, the abnormality detection means performs the on-drive abnormality detection process after confirming that no on-failure has occurred in the non-load side switch means and the load side switch means by the off-drive abnormality detection process. It has become.

  This is because when an on-drive abnormality detection process is performed in which one of the non-load side switch means and the load side switch means has an on-failure and the other switch means is a specific switch means, This is because the electric load to be functioned is unnecessarily energized, but such a problem can be reliably avoided. In addition, when an on-failure has occurred in one of the non-load-side switch means and the load-side switch means, an on-drive abnormality detection process is performed using the switch means with the on-failure as the specific switch means. However, since the on-failure originally does not occur and the off-failure does not occur, it is meaningless to perform the on-drive abnormality detection process itself.

Next, in the starter control device of the sixth invention, in the starter control device of the third to fifth inventions , the vehicle is stopped when a predetermined automatic stop condition is satisfied, and then the predetermined automatic start condition is satisfied. Then, an idle stop control means for restarting the engine is provided, and when the idle stop control means restarts the engine, the starter control device includes the energization switch means (that is, the non-load side switch means and The starter is made to function by turning on the load side switch means). In addition, the starter control device allows the idle stop control means to stop the engine when an abnormality detection means detects an off failure of either the non-load side switch means or the load side switch means. It is forbidden.

And according to this composition, it can prevent beforehand that an engine becomes inoperable.
In other words, if any of the non-load side switch means and the load side switch means has an off-failure, the starter cannot function, so an idle stop vehicle (a vehicle equipped with an idle stop control means). In this case, if the idle stop control means stops the engine, the subsequent automatic engine restart cannot be performed, and the vehicle may not be able to travel on the road. Therefore, when an off-failure of either the non-load side switch means or the load side switch means is detected, the vehicle cannot run by prohibiting idle stop (automatic engine stop by the idle stop control means). It can be prevented in advance.

In particular, according to the starter control device of the third to fifth inventions cited by the starter control device of the sixth invention , any off-failure of the non-load side switch means and the load side switch means is caused to the electric load. This can be done without turning on the power, which means that it is possible to detect anomalies without actually functioning the starter. As a result, before the idling stop (automatic stop of the engine by the idling stop control means) Before that, an abnormality that makes it impossible to restart the engine can be detected. By detecting an abnormality that prevents the engine from being restarted before the idle stop and prohibiting the idle stop, it is possible to prevent the vehicle from being restarted on the road. It is very effective in enhancing.

  In addition to prohibiting the idling stop, as described above, if the vehicle driver is urged not to stop the engine, it is possible to prevent the driver from stopping the engine on his / her own will. As a result, the effect of preventing the vehicle from running can be further enhanced.

  By the way, when the starter is an independent control type, there are two electric loads, that is, a first electric load and a second electric load, each of which is energized independently, as an electric load for causing the starter to function. The starter functions when energized by the two electric loads. That is, one of the two electric loads is an electric load for meshing the starter pinion gear with the ring gear of the engine, and the other is for applying a rotational driving force for cranking to the pinion gear. Electric load.

  In this case, the starter control device, as the load-side switch means, includes a first load-side switch means for switching energization / non-energization to the first electric load, and energization / non-energization to the second electric load. Two switch means including a second load side switch means for switching energization are provided.

  As a specific connection form, one terminal of the pair of terminals of the first load side switch means is connected to a terminal on the opposite side to the second potential side of the non-load side switch means, and the other terminal. Is connected to the end of the first electric load opposite to the first potential side. Similarly, one terminal of the pair of terminals of the second load side switch means is connected to a terminal opposite to the second potential side of the non-load side switch means, and the other terminal is connected to the second terminal. It is connected to the end of the electrical load opposite to the first potential side. That is, the series circuit of the first load side switch means and the first electric load and the series circuit of the second load side switch means and the second electric load are not connected to the non-load side switch means. Each is provided in series and in parallel with each other.

  In this configuration, for example, the first electric load is an electric load for meshing the starter pinion gear with the ring gear of the engine, and the second electric load applies a rotational driving force for cranking to the pinion gear. If the starter control device turns on the non-load side switch means and turns on the first load side switch means, the starter control device energizes the first electric load. The pinion gear can be meshed with the ring gear, and further, if the second load side switch means is turned on, the second electric load can be energized to give a rotational driving force to the pinion gear. The starter can crank the engine.

In the case of this configuration, if it is a starter control device of the third to sixth inventions , it is preferable to adopt the configuration of the following seventh invention. In the starter control device according to the seventh aspect of the invention, the abnormality detection means drives the first load side switch means to turn on as an on-drive abnormality detection process using the load side switch means as the specific switch means, In a state where the non-load side switch means and the second load side switch means are driven to be turned off, the voltage of the inter-switch path is monitored, and based on the voltage, the first load side switch means is turned off. First load-side switch means for detecting failure and abnormality detection processing at the time of driving, and the second load-side switch means are driven to turn on, and the non-load-side switch means and the first load-side switch means The second load that monitors the voltage of the inter-switch path in a state of being driven to turn off, and detects an off-fault of the second load side switch means based on the voltage. Switch means on the drive-time abnormality detection processing, it intends to carry. That is, since the first and second load side switch means are provided in parallel, it is only necessary to turn on the two load side switch means one by one and detect an off failure of each load side switch means.

In this way, it is possible to detect off-failures of the first load side switch means and the second load side switch means.
Of the two electric loads for causing the starter to function, as an electric load for meshing the pinion gear with the ring gear, a solenoid coil for moving the pinion gear to a position for meshing with the ring gear can be considered. In addition, as an electric load for applying a rotational driving force for cranking to the pinion gear, a coil of an electromagnetic switch that operates the motor by communicating an energization path to the motor that rotationally drives the pinion gear, or The motor itself can be considered.

It is a block diagram showing ECU (electronic control apparatus) of 1st Embodiment, and its peripheral device. It is explanatory drawing showing the relationship between the threshold voltage of a comparator, and a power supply voltage. It is explanatory drawing which represented the state of the engine in time series. It is explanatory drawing showing the combination of the content of the abnormality detected in 1st Embodiment, the drive state of a relay, and the output of a comparator. It is explanatory drawing explaining the treatment content for fail safe. It is a flowchart showing the abnormality detection process of 1st Embodiment. It is a flowchart showing the fail safe process performed in the abnormality detection process of 1st Embodiment. It is a block diagram showing ECU (electronic control apparatus) and its peripheral device of 2nd Embodiment. It is explanatory drawing showing the combination of the content of the abnormality detected in 2nd Embodiment, the drive state of a relay, and the output of a comparator. It is a flowchart showing the abnormality detection process of 2nd Embodiment. It is a flowchart showing the fail safe process performed in the abnormality detection process of 2nd Embodiment.

Hereinafter, a starter control device according to an embodiment to which the present invention is applied will be described.
[First Embodiment]
First, FIG. 1 is a configuration diagram showing two electronic control units (hereinafter referred to as ECUs) 11 and 12 and their peripheral devices according to the first embodiment. The ECUs 11 and 12 cooperatively control a starter 13 that cranks a vehicle engine (not shown) for starting. The ECU 11 also performs idle stop control for automatically stopping and automatically starting the engine. The ECU 12 also has a role of monitoring whether the ECU 11 is operating normally. Here, the description will be made assuming that the transmission of the vehicle is a manual transmission.

  The ECU 11 has a starter signal and a brake pedal that are activated when the vehicle driver performs a starting operation (for example, an operation of twisting a key inserted in a key cylinder to a start position or an operation of pressing a start button). The brake signal from the sensor that detects the depression, the accelerator signal from the sensor that detects that the accelerator pedal has been depressed, the clutch signal from the sensor that detects that the clutch pedal has been depressed, and the shift lever operating position (shift position) ) For detecting a shift position, a vehicle speed signal from a sensor for detecting a vehicle traveling speed (vehicle speed), a brake negative pressure signal from a sensor for detecting brake negative pressure (negative pressure of a brake booster), In addition, rotation signals from a crankshaft sensor and a camshaft sensor are input. The battery voltage monitor terminal 14 of the ECU 11 is inputted with a battery voltage VB (about 12 V in the present embodiment) that is a voltage of a plus terminal of the in-vehicle battery 15 as a power source. For example, when the battery voltage VB is supplied to the ignition system power supply line in the vehicle (when ignition is on), the ECUs 11 and 12 operate with the power from the ignition system power supply line.

  On the other hand, the starter 13 includes a motor (starter motor) 17 that serves as a power source for cranking the engine, an electromagnetic switch 19 that energizes the motor 17 to operate the motor 17, a pinion gear 21 that is rotationally driven by the motor, and a pinion gear. And a pinion control solenoid 23 for moving 21.

  One end of the motor 17 is connected to a ground (GND) line that is a line on the negative terminal side of the battery 15, and the electromagnetic switch 19 is a line 16 of the battery voltage VB in the vehicle (a line on the positive terminal side of the battery 15). This is a large relay provided in the energization path from the motor to the other end of the motor 17. The electromagnetic switch 19 is alternatively driven into an on state that communicates the energization path and an off state that blocks the energization path.

  Specifically, the electromagnetic switch 19 includes a coil 19 a having one end connected to the ground line, and a pair of contacts 19 b and 19 c provided on the energization path to the motor 17. When the battery voltage VB is applied to the other end of the coil 19a and the coil 19a is energized, the contacts 19b and 19c are short-circuited to connect the energization path (this state is on), and the coil 19a is not energized. Then, the contacts 19b and 19c are opened to cut off the energization path (this state is an off state).

  The pinion control solenoid 23 is a solenoid as an actuator for switching the pinion gear 21 between a state in which the pinion gear 21 is engaged with the ring gear 25 of the engine and a state in which the pinion gear 21 is not engaged with the ring gear 25.

  Specifically, the pinion control solenoid 23 has a coil 23a whose one end is connected to the ground line and a biasing member (not shown) such as a spring. If the coil 23a is not energized, the pinion gear 21 is arranged at an initial position (position shown in FIG. 1) where it does not mesh with the ring gear 25 by the force of the urging member. When the battery voltage VB is applied to the other end of the coil 23a and the coil 23a is energized, the pinion gear 21 is moved outwardly of the starter 13 as indicated by the dotted arrow in FIG. And is engaged with the ring gear 25.

  If the motor 17 is energized by turning on the electromagnetic switch 19 with the pinion gear 21 engaged with the ring gear 25, the rotational force of the motor 17 is transmitted to the ring gear 25 via the pinion gear 21, and the engine is cranked. It will be.

  Further, in the vehicle, the battery voltage VB is applied to the other end (upstream side: opposite to the ground line side) of the coil 23a of the pinion control solenoid 23 by turning on outside the ECUs 11 and 12 and A relay (hereinafter also referred to as a pinion drive relay) 27 is provided to pass a current through the coil 23a and mesh the pinion gear 21 with the ring gear 25.

  Similarly, the battery voltage VB is applied to the other end (upstream side: opposite to the ground line side) of the coil 19a of the electromagnetic switch 19 by turning on the outside of the ECUs 11 and 12, and current is supplied to the coil 19a. And a relay (hereinafter also referred to as a motor drive relay) 28 for operating the motor 17 by turning on the electromagnetic switch 19 is provided.

  Further, a common current path that is upstream of both the pinion drive relay 27 and the motor drive relay 28 and extends from the battery voltage VB line 16 to the relays 27 and 28 is connected to and disconnected from the current path. A relay (hereinafter also referred to as an upstream cut relay) 29 is provided.

  More specifically, first, the upstream cut relay 29 includes a coil 29a that is energized when the battery voltage VB is supplied to one end and the other end is grounded by the ECU 12 (that is, connected to the ground line), A pair of terminals 29b and 29c that are short-circuited by energization of the coil 29a are provided. One terminal 29b is connected to the line 16 of the battery voltage VB. Therefore, in the upstream cut relay 29, when the terminal 29b and the terminal 29c are short-circuited by energization of the coil 29a (this state is ON of the relay 29), the terminal 29c leads to the pinion drive relay 27 and the motor drive relay 28 side. The battery voltage VB is output.

  The pinion drive relay 27 includes a coil 27a that is energized when the battery voltage VB is supplied to one end and the other end is grounded by the ECU 11, and a pair of terminals 27b and 27c that are short-circuited by energization of the coil 27a. It has. One terminal 27b is connected to the terminal 29c of the upstream cut relay 29, and the other terminal 27c is connected to the other end (upstream side) of the coil 23a of the pinion control solenoid 23. Therefore, the pinion drive relay 27 is configured such that the terminal 27b and the terminal 27c are short-circuited by energization of the coil 27a (this state is the relay 27 being turned on), whereby the terminal 29c of the upstream cut relay 29 and the coil of the pinion control solenoid 23 23a is connected.

  Similarly, in the motor drive relay 28, a battery voltage VB is supplied to one end and the other end is grounded by the ECU 11, and a pair of terminals 28b and 28c are short-circuited by energization of the coil 28a. And. One terminal 28 b is connected to the terminal 29 c of the upstream cut relay 29, and the other terminal 28 c is connected to the other end (upstream side) of the coil 19 a of the electromagnetic switch 19. Therefore, in the motor drive relay 28, the terminal 28b and the terminal 28c are short-circuited by energization of the coil 28a (this state is the relay 28 being turned on), so that the terminal 29c of the upstream cut relay 29 and the coil 19a of the electromagnetic switch 19 Will be connected.

  For this reason, in the current path from the battery voltage VB to the coil 23a of the pinion control solenoid 23, the upstream cut relay 29 and the pinion drive relay 27 are connected in series as a switch for connecting and disconnecting the current path. In addition, an upstream cut relay 29 and a motor drive relay 28 are connected in series as switches for connecting and disconnecting the current path in the current path from the battery voltage VB to the coil 19a of the electromagnetic switch 19. In addition, the upstream cut relay 29 is disposed in the common current path of the two coils 19a and 23a. In other words, a series circuit of the pinion drive relay 27 and the coil 23a and a series circuit of the motor drive relay 28 and the coil 19a are provided in series with the upstream cut relay 29 and in parallel with each other. It has been.

  Therefore, if the upstream cut relay 29 is turned on and the pinion drive relay 27 is turned on, the coil 23a can be energized to engage the pinion gear 21 with the ring gear 25, and the motor drive relay 28 can be turned on. For example, the coil 19a can be energized to apply a rotational driving force from the motor 17 to the pinion gear 21, and as a result, the starter 13 can crank the engine.

  Next, the ECU 11 includes a microcomputer 31 that executes various processes for idle stop control and control of the starter 13, an input circuit 33 that inputs various signals such as the above-described starter signal to the microcomputer 31, and a battery voltage monitor terminal 14. Is provided between the two resistors 35 and 37 that divide the battery voltage VB input from the voltage into a voltage value within a range that can be input to the microcomputer 31, and the voltage line at the connection point between the resistors 35 and 37 and the ground line. The noise removing capacitor 39 is provided. The microcomputer 31 detects the battery voltage VB by A / D converting the voltage at the connection point between the resistors 35 and 37 with an internal A / D converter (not shown). Further, the microcomputer 31 detects the voltage value of the analog signal of the signal input from the input circuit 33 by A / D conversion with an internal A / D converter.

  In addition, the ECU 11 has two output terminals connected between the terminal J1 connected to the downstream side of the coil 27a of the pinion drive relay 27 (the side opposite to the battery voltage VB side) and the terminal J1 and the ground line. Two output terminals are connected between the terminal J2 to which the transistor T1 and the downstream side of the coil 28a of the motor drive relay 28 (the side opposite to the battery voltage VB side) are connected, and the terminal J2 and the ground line. And a transistor T2.

  The transistors T1 and T2 are controlled by the microcomputer 31. When the transistor T1 is turned on, a current flows through the coil 27a, the pinion drive relay 27 is turned on, and when the transistor T2 is turned on, the coil is turned on. A current flows through 28a and the motor drive relay 28 is turned on. In the present embodiment, the transistors T1 and T2 are N-channel MOSFETs.

  Furthermore, one end of the abnormality detection wiring Lm is connected to a predetermined position of the current path (corresponding to the path between the switches) between the upstream cut relay 29, the pinion drive relay 27, and the motor drive relay 28 outside the ECU 11. ing. In this embodiment, one end of the abnormality detection wiring Lm is connected to the branch point P of each current path from the upstream cut relay 29 to each of the pinion drive relay 27 and the motor drive relay 28. The connection destination is not necessarily the branch point P.

  The other end of the abnormality detection wiring Lm is connected to the terminal J3 of the ECU 11. Therefore, the voltage of the current path between the upstream cut relay 29, the pinion drive relay 27, and the motor drive relay 28 (hereinafter referred to as an inter-relay voltage) is input to the ECU 11 via the terminal J3.

  Then, the ECU 11 detects the failure of the three relays 27 to 29, between the pull-up resistor R1 connected between the terminal J3 and the battery voltage VB line, and between the terminal J3 and the ground line. And a voltage monitor circuit 50 for monitoring a voltage Vm of the terminal J3 (also a voltage between relays, hereinafter referred to as a terminal voltage) Vm.

  The voltage monitor circuit 50 includes two comparators 51 and 52 each having a non-inverting input terminal (+ terminal) connected to the terminal J3, and a constant voltage VD generated in the ECU 11 (in this embodiment). 5V) and the pull-up resistor 53 connected between the output terminal of the comparator 51 and the pull-up resistor 53 connected between the constant voltage VD line and the output terminal of the comparator 52. The resistor 54, the battery voltage VB is divided, the divided voltage is input to the inverting input terminal (− terminal) of the comparator 51 as the first threshold voltage Vth1, and the battery voltage VB is divided. And two resistors 57 and 58 for inputting the divided voltage to the inverting input terminal (− terminal) of the comparator 52 as the second threshold voltage Vth2.

  Then, the output CM 1 of the comparator 51 and the output CM 2 of the comparator 52 are input to the microcomputer 31. Since the output circuit inside the comparators 51 and 52 is a current drawing type (open collector or open drain), in order to enable the comparators 51 and 52 to output a high (= 5 V) signal, Pull-up resistors 53 and 54 are provided.

  The resistance value r1 of the resistor R1 is such that even if the relay 27 is turned on when the relay 29 is turned off, a current (for example, 10 A or more) that allows the pinion control solenoid 23 to operate flows through the coil 23a of the pinion control solenoid 23. In order to prevent a current (for example, 10 A or more) that can operate (turn on) the electromagnetic switch 19 from flowing through the coil 19a of the electromagnetic switch 19 even if the relay 28 is turned on when the relay 29 is turned off. The value is set to a sufficiently large value. For example, the value is set to a value about several thousand times to several tens of thousands times the resistance value of the coils 19a and 23a.

  Furthermore, the resistance value r1 of the resistor R1 and the resistance value r2 of the resistor R2 are set so as to satisfy the relationship “r1 = r2”. In the present embodiment, for example, “r1 = r2 = 10 KΩ”. Therefore, the terminal voltage Vm when the three relays 27 to 29 are off is a voltage obtained by dividing the battery voltage VB by r1 and r2, as shown in FIG. 2 (VB / 2).

  On the other hand, in the voltage monitor circuit 50, the resistance values of the resistors 55 and 56 are such that the first threshold voltage Vth1 input to the comparator 51 is 3/4 of the battery voltage VB (VB · The ratio of “1: 3” is set so as to be 3/4). The resistance values of the resistors 57 and 58 are such that the second threshold voltage Vth2 input to the comparator 52 becomes a voltage (VB / 4) that is 1/4 of the battery voltage VB, as shown in FIG. , A ratio of “3: 1” is set.

  Then, the microcomputer 31 of the ECU 11 detects an abnormality or the like of the relays 27 to 29 based on the correspondence between the driving state of the relays 27 to 29 and the outputs CM1 and CM2 of the comparators 51 and 52. The processing content for detecting an abnormality will be described later.

  Next, the ECU 12 has two terminals between the microcomputer 41, a terminal J4 connected to the downstream side of the coil 29a of the upstream cut relay 29 (opposite the battery voltage VB side), and the terminal J4 and the ground line. And a transistor T3 to which an output terminal is connected. Therefore, when the transistor T3 is turned on, a current flows through the coil 29a and the upstream cut relay 29 is turned on. In the present embodiment, the transistor T3 is also an N-channel MOSFET.

  Furthermore, the microcomputer 41 of the ECU 12 is communicably connected to the microcomputer 31 of the ECU 11 via the communication line 43. Then, the microcomputer 41 communicates with the microcomputer 31 of the ECU 11 and turns on or off the transistor T3 in accordance with a command from the microcomputer 31.

  In addition, the microcomputer 41 of the ECU 12 determines whether or not the microcomputer 31 is operating normally by communication with the microcomputer 31. If the microcomputer 31 determines that the microcomputer 31 is not operating normally, the microcomputer 41 is involved in a command from the microcomputer 31. First, the transistor T3 is kept off so that the upstream cut relay 29 is not turned on, and even if one or both of the relays 27 and 28 are turned on by the ECU 11 (microcomputer 31), the pinion gear 21 is turned on. The motor 17 is not operated. This is to prevent the starter 13 (pinion gear 21 and motor 17) from malfunctioning due to an abnormality of the microcomputer 31.

Next, the content of the control process performed by the microcomputer 31 of the ECU 11 will be described with reference to FIG. FIG. 3 shows the state of the engine in time series.
First, the microcomputer 31 performs a starter control process in which the starter 13 cranks the engine in order to start the engine when the driver of the vehicle performs a start operation and the starter signal becomes an active level (for example, high). This is the initial start state (1) in FIG.

  As a specific process, the microcomputer 31 initially turns off all of the transistors T1 and T2 of the ECU 11 and the transistor T3 of the ECU 12. As described above, the microcomputer 31 controls the on / off of the transistor T3 by instructing the microcomputer T3 to communicate with the microcomputer 41 of the ECU 12 with respect to the transistor T3.

  When the starter 13 cranks the engine, the microcomputer 31 turns on the transistor T3 of the ECU 12 and also turns on the transistor T1, thereby turning on the upstream cut relay 29 and the pinion drive relay 27, and for pinion control. An electric current is passed through the coil 23 a of the solenoid 23 to mesh the pinion gear 21 with the ring gear 25. Further, the microcomputer 31 turns on the transistor T2, thereby turning on the motor drive relay 28, and passing a current through the coil 19a of the electromagnetic switch 19 to turn on the electromagnetic switch 19.

  Then, an electric current flows from the battery 15 to the motor 17 so that the motor 17 operates (rotates), and the pinion gear 21 rotates the ring gear 25 by the rotational force of the motor 17 (that is, the engine is cranked). When the engine is cranked, fuel injection and ignition for the engine are performed by another ECU that controls the engine. If the engine is a diesel engine, ignition is not performed and only fuel injection is performed. Further, a system configuration in which such control of the engine is also performed by the ECU 11 may be employed.

  When the microcomputer 31 determines that the engine is in a complete explosion state (starting is complete, so-called engine started state), the three transistors T1 to T3 are turned off and the three relays 27 to 29 are turned off. Is turned off to stop energization of the motor 17 and return the pinion gear 21 to the initial position where it does not mesh with the ring gear 25. The microcomputer 31 calculates the engine speed from the aforementioned rotation signal, and determines whether or not the engine has reached a complete explosion based on the engine speed.

The above is the content of the starter control process. When the engine is in an operating state, the engine is operating (2) in FIG.
Next, during engine operation, if the microcomputer 31 determines that a predetermined automatic stop condition is satisfied, the microcomputer 31 performs processing to stop fuel injection to the engine or to shut off the intake air supply path to the engine. The engine is automatically stopped. The state in which the engine is automatically stopped in this way is during idle stop (3) in FIG.

Note that, as the automatic stop condition, for example, the following all conditions are satisfied.
Battery voltage VB is greater than or equal to a predetermined value. The vehicle speed is below a predetermined value. The absolute value of the brake negative pressure is greater than or equal to a predetermined value. The brake pedal is depressed. The shift position is neutral or the clutch pedal is depressed with the shift position other than neutral. The accelerator pedal is not depressed. More than a certain time has passed since the last time the engine was automatically stopped and restarted.

  Thereafter, if the microcomputer 31 determines that a predetermined automatic start condition is satisfied during the idle stop, the microcomputer 31 performs the above-described starter control process in order to restart the engine. This is the restart state (4) in FIG.

As the automatic start condition, for example, any of the following conditions can be considered.
When the engine was idle stopped when the shift position was other than neutral and the clutch pedal was depressed, the brake pedal was released in that state. The brake pedal was kept depressed, but the clutch pedal was released (ie, the operation of trying to connect the clutch by releasing the clutch pedal) when the shift position was not neutral. The brake pedal was still depressed, but the shift position was operated from neutral to something other than neutral (the clutch pedal was depressed at that time).

  Further, “stop” at the right end in FIG. 3 indicates that the engine has been stopped by the driver performing an operation to stop the engine, and in this case, the ignition system power supply in the vehicle is also turned off. .

  Here, the microcomputer 31 of the ECU 11 performs an abnormality detection process mainly for detecting a failure of the relays 27 to 29 during the operation of the engine described above ((2) in FIG. 3). The abnormality detection process may be performed, for example, immediately after the above-described initial engine start is completed or periodically during engine operation. Further, the abnormality detection process may be performed even during idling stop of the engine ((3) in FIG. 3).

  Next, the abnormality detection process will be described. In the following, the outputs CM1 and CM2 of the comparators 51 and 52 may be simply referred to as CM1 and CM2. Further, the abnormality detection wiring Lm connected to the terminal J3 is referred to as a monitor path Lm. Further, the resistance values (about 1Ω) of the coils 19a and 23a of the electromagnetic switch 19 and the pinion control solenoid 23 in the starter 13 are compared with the resistance values r1 and r2 (= 10KΩ) of the resistors R1 and R2 in the ECU 11, respectively. Since it is sufficiently small, in the following description, the resistance values of the coils 19a and 23a are ignored (0Ω).

First, the abnormality detection principle will be described with reference to FIG.
If normal, when the three relays 27 to 29 are turned off, as described above, the terminal voltage Vm is neither the ground voltage (ground line voltage = 0 V) nor the battery voltage VB “VB / 2”. Therefore, CM1 becomes low (Lo) and CM2 becomes high (Hi) as shown in the column of “normal” in the row of “inspection drive mode (1)” in FIG. This is because “VB / 2” is lower than the first threshold voltage Vth1 of the comparator 51 and higher than the second threshold voltage Vth2 of the comparator 52 (see FIG. 2).

  On the other hand, if an ON failure occurs in the upstream cut relay 29, the terminal voltage Vm remains at the battery voltage VB, so the terminal voltage Vm when the three relays 27 to 29 are turned off is also naturally. Battery voltage VB (> Vth1). Note that turning off means driving to turn off, and not necessarily turning off.

  Therefore, if the upstream cut relay 29 is turned on, if the three relays 27 to 29 are turned off, as shown in the column (a) in the row of “inspection drive mode (1)” in FIG. , CM1 and CM2 are both high.

  Further, even if a power supply short circuit (short circuit to the battery voltage VB) occurs in the monitor path Lm, the upstream cut relay 29 is the same as the on-failure in that the terminal voltage Vm remains the battery voltage VB. . For this reason, even if a power supply short circuit occurs in the monitor path Lm, when the three relays 27 to 29 are turned off, it is shown in the column (b) in the “inspection drive mode (1)” row of FIG. Thus, both CM1 and CM2 are high.

  In other words, a power supply short circuit in the monitor path Lm can be detected as an ON failure of the upstream cut relay 29. Therefore, in the following, as shown in the bottom row of FIG. 4, the ON failure of the upstream cut relay 29 and the power supply short circuit of the monitor path Lm are classified as “abnormal [1]”.

  On the other hand, if an on-failure occurs in the pinion drive relay 27 or an on-failure occurs in the motor drive relay 28, the terminal voltage Vm when the three relays 27 to 29 are turned off is the second threshold value. It becomes 0 V lower than the voltage Vth2. Actually, the voltage of the battery voltage VB is divided by the resistor R1 and one of the coils 19a and 23a, but the resistance value of the coils 19a and 23a is ignored with respect to the resistance value r1 of the resistor R1. Since it is as small as possible, the terminal voltage Vm is a small voltage that can be regarded as 0V.

  For this reason, if the pinion drive relay 27 or the motor drive relay 28 is on-failed, if the three relays 27 to 29 are turned off, the lines (c) and “c” in the row of “test drive mode (1)” in FIG. As shown in each column of (d), both CM1 and CM2 are low.

  Further, even if a ground short (a short to the ground line) of the monitor path Lm occurs, it is the same as any of the relays 27 and 28 being on-failed in that the terminal voltage Vm becomes 0V (<Vth2). It is. For this reason, even if a ground short occurs in the monitor path Lm, when the three relays 27 to 29 are turned off, it is shown in the column (e) in the “inspection drive mode (1)” row of FIG. Thus, both CM1 and CM2 are low.

  In other words, a ground short in the monitor path Lm can also be detected as an ON failure of one of the relays 27 and 28. Therefore, in the following, as shown in the bottom row of FIG. 4, the ON failure of the pinion drive relay 27, the ON failure of the motor drive relay 28, and the ground short of the monitor path Lm are classified as “abnormal [2]”. To do.

  From the above, the microcomputer 31 identifies and detects the abnormality [1] and the abnormality [2] by the combination of CM1 and CM2 when the three relays 27 to 29 are turned off. That is, if both CM1 and CM2 are high, it is determined that abnormality [1] has occurred, and if both CM1 and CM2 are low, it is determined that abnormality [2] has occurred.

  On the other hand, even if an off failure occurs in any of the relays 27 to 29, the terminal voltage Vm when the three relays 27 to 29 are turned off is “VB / 2”, which is the same as in a normal state. That is, since the relays 27 to 29 are turned off, the influence of the off failure does not appear. Therefore, when the three relays 27 to 29 are turned off, even if an off failure has occurred in any of the relays 27 to 29, CM1 and CM2 have the same output values as in the normal state. As shown in the columns (g), (h), and (i) in the row of the “inspection drive mode (1)”, CM1 is low and CM2 is high.

  This also applies to the case where the monitor path Lm is disconnected. That is, when the monitor path Lm is disconnected, the terminal voltage Vm is always “VB / 2” regardless of the on / off state of the relays 27 to 29. Therefore, when the three relays 27 to 29 are turned off, Even if the disconnection of the monitor path Lm occurs, CM1 and CM2 have the same output values as in the normal state, and as shown in the column (f) in the “inspection drive mode (1)” row of FIG. Is low and CM2 is high.

  Here, when only the pinion drive relay 27 is turned on among the three relays 27 to 29, if it is normal, the terminal voltage Vm is 0 V lower than the second threshold voltage Vth2. As shown in the “normal” column in the “drive mode (2)” row, both CM1 and CM2 are low.

  On the other hand, if the pinion drive relay 27 has an off failure, when only the pinion drive relay 27 of the three relays 27 to 29 is turned on, the relay 27 is not actually turned on. Similarly to the case where the three relays 27 to 29 are turned off, the terminal voltage Vm becomes “VB / 2”. For this reason, the column (h) in the row of “inspection drive mode (2)” in FIG. As shown, CM1 is low and CM2 is high. Note that turning on means driving to turn on and does not necessarily turn on.

  Therefore, the microcomputer 31 can detect an off failure of the pinion drive relay 27 by CM1 and CM2 when only the pinion drive relay 27 is turned on among the three relays 27 to 29.

  Similarly, even when only the motor drive relay 28 is turned on among the three relays 27 to 29, if it is normal, the terminal voltage Vm becomes 0V, so “inspection drive mode (3)” of FIG. As shown in the “normal” column in the row, both CM1 and CM2 are low.

  On the other hand, if the motor drive relay 28 has an off failure, when only the motor drive relay 28 of the three relays 27 to 29 is turned on, the relay 28 is not actually turned on. The terminal voltage Vm becomes “VB / 2”. Therefore, as shown in the column (i) in the row of “test driving mode (3)” in FIG. 4, CM1 is low and CM2 is high. .

  Therefore, the microcomputer 31 can detect an OFF failure of the motor drive relay 28 based on CM1 and CM2 when only the motor drive relay 28 is turned on among the three relays 27 to 29.

  Further, when only the upstream cut relay 29 is turned on among the three relays 27 to 29, if it is normal, the terminal voltage Vm becomes the battery voltage VB higher than the first threshold voltage Vth1, and therefore, “ As shown in the “normal” column in the row of “inspection drive mode (4)”, both CM1 and CM2 become high.

  On the other hand, if the upstream cut relay 29 has an off failure, when only the upstream cut relay 29 of the three relays 27 to 29 is turned on, the relay 29 is not actually turned on. The terminal voltage Vm becomes “VB / 2”. Therefore, as shown in the column (g) in the row of “test drive mode (4)” in FIG. 4, CM1 is low and CM2 is high. .

  Therefore, the microcomputer 31 can detect an off failure of the upstream cut relay 29 by CM1 and CM2 when only the upstream cut relay 29 is turned on among the three relays 27 to 29.

  However, if the monitor path Lm is disconnected, the terminal voltage Vm is always “VB / 2” as described above. Therefore, in each row of “inspection drive modes (2) to (4)” in FIG. As shown in the column (f), in each case where any one of the three relays 27 to 29 is turned on, CM1 is low and CM2 is high. And this means the following.

  That is, when only the pinion drive relay 27 among the three relays 27 to 29 is turned on, if “CM1 = low, CM2 = high”, it is assumed that an off failure of the relay 27 has occurred as an abnormality. It is conceivable that the monitor path Lm may be disconnected. Similarly, when only the motor drive relay 28 is turned on, if “CM1 = low, CM2 = high”, an abnormality is assumed. It can be considered that an off failure of the relay 28 has occurred, but there is a possibility that the monitor path Lm is disconnected. Similarly, when only the upstream cut relay 29 is turned on, If “CM1 = low, CM2 = high”, it is considered that there is an off failure of the relay 29 as an abnormality, but there is a possibility that the monitor path Lm may be disconnected. That.

  The disconnection of the monitor path Lm may be detected as an off failure of the relays 27 to 29 without being distinguished from an off failure of the relays 27 to 29. Any of the OFF faults and disconnection of the monitor path Lm can be identified as follows.

  For example, assuming that the pinion drive relay 27 is not in failure, but that the monitor path Lm is not disconnected, each of the three relays 27 to 29 in which the relays 28 and 29 other than the pinion drive relay 27 are turned on. As shown in column (h) in each row of “inspection drive modes (3), (4)” in FIG. 4, CM1 and CM2 do not become “CM1 = low, CM2 = high” The logic level is the same as normal.

  Similarly, if the motor drive relay 28 is not in failure, but is disconnected from the monitor path Lm, each of the relays 27 and 29 other than the motor drive relay 28 among the three relays 27 to 29 is turned on. In this case, CM1 and CM2 do not become “CM1 = low, CM2 = high” as shown in the column (i) in each row of “inspection drive mode (2), (4)” in FIG. The logic level is the same as normal.

  Similarly, assuming that the upstream cut relay 29 is not broken, and that the monitor path Lm is not disconnected, the relays 27 and 28 other than the upstream cut relay 29 among the three relays 27 to 29 are turned on. In each case, as shown in the column (g) in each row of the “inspection drive modes (2) and (3)” in FIG. 4, CM1 and CM2 are “CM1 = low, CM2 = high”. However, the logic level is the same as normal.

  Therefore, the microcomputer 31 verifies CM1 and CM2 in each case where the three relays 27 to 29 are turned on one by one, and if only one of them becomes “CM1 = low, CM2 = high” When “CM1 = low, CM2 = high”, it can be determined that the relay that has been turned on has an off failure. In any case, if “CM1 = low, CM2 = high”, and if CM1 and CM2 have the same logic level as in normal cases, “CM1 = low, CM2 = high”. In this case, it can be determined that the relay that is turned on has a failure. On the other hand, if “CM1 = low, CM2 = high” in at least two cases, it can be determined that the monitor path Lm is not broken, not a relay OFF failure.

  Note that if either the pinion drive relay 27 or the motor drive relay 28 and the upstream cut relay 29 are not turned on at the same time, current will not flow through the coils 23a, 19a. 13 does not function unnecessarily.

  On the other hand, as shown in each column of (a) and (b) in each row of “inspection drive modes (2) to (4)” in FIG. 4, the ON failure of the upstream cut relay 29 and the power supply short of the monitor path Lm. When either of the three relays 27 to 29 is turned on, both CM1 and CM2 become high. This is because the terminal voltage Vm remains the battery voltage VB. Further, as shown in the column (e) in each row of the “inspection drive modes (2) to (4)” in FIG. 4, if a ground short of the monitor path Lm occurs, the three relays 27 to 29 are connected. Regardless of which is turned on, both CM1 and CM2 are low. This is because the terminal voltage Vm remains 0V. Further, as shown in each column of (c) and (d) in each row of “inspection drive modes (2) to (4)” in FIG. 4, either the pinion drive relay 27 or the motor drive relay 28 is used. If an ON failure occurs, when the upstream cut relay 29 is turned on, the terminal voltage Vm becomes the battery voltage VB, so that both CM1 and CM2 become high and either one of the relays 27 and 28 is turned on. In this case, since the terminal voltage Vm remains 0V, both CM1 and CM2 are low.

The above is the abnormality detection principle.
Next, the contents of the fail-safe treatment performed when the microcomputer 31 detects an abnormality will be described with reference to FIG. In the following, as shown in the bottom row of FIG. 4 and FIG. 5, in addition to the above-described classification of abnormality [1] and abnormality [2], the disconnection of the monitor path Lm is classified as “abnormality [3]”. The off failure of the upstream cut relay 29 is classified as “abnormal [4]”, the off failure of the pinion drive relay 27 is classified as “abnormal [5]”, and the off failure of the motor drive relay 28 is classified as “abnormal [6]”. ".

  As shown in FIG. 5, when the microcomputer 31 detects an abnormality [1], the microcomputer 31 issues a warning indicating that “the start circuit is short-circuited” as a user caution (warning to the vehicle user) process. The abnormality information indicating that the abnormality [1] has occurred is stored in a nonvolatile memory or the like (not shown in FIG. 5), and further, idle stop (automatic engine stop) is performed. Perform processing to prohibit.

  As a process for giving a warning to the vehicle user, a message indicating the content of the warning is displayed on a display device or output from a speaker with sound, and a warning lamp indicating the content of the warning is turned on. Processing to be performed can be considered.

  Further, as a process for prohibiting idle stop, a process of setting (setting 1) an idle stop prohibition flag is conceivable. That is, when the idle stop prohibition flag is 1, the microcomputer 31 does not determine whether the automatic stop condition is satisfied during engine operation, or determines that the automatic stop condition is satisfied. The process of stopping is stopped.

On the other hand, the reason why the idle stop is prohibited when the abnormality [1] is detected is as follows.
Even if the abnormality [1] occurs, it is possible to control energization / non-energization of the coils 23a and 19a (and control of the starter 13) by turning the relays 27 and 28 on / off. When the relays 27 and 28 are turned on, there is a possibility that the normal relays 27 and 28 are turned on, and if this happens, an effective current (that is, a pinion control solenoid) is applied to the coil 23a or the coil 19a. 23 or a current that allows the electromagnetic switch 19 to operate unnecessarily), and the pinion gear 21 or the motor 17 unnecessarily operates. . The operation of the pinion gear 21 means that the pinion gear 21 moves to a position where the pinion gear 21 meshes with the ring gear 25 (and hits the ring gear 25).

  For this reason, when the abnormality [1] is detected, the idling stop is prohibited, thereby reducing the opportunity for the starter 13 to function, and even the normal downstream relays 27 and 28 are on-failed. Is prevented.

  Further, the microcomputer 31 detects the abnormality [1] in a state where the three relays 27 to 29 are driven to be turned off. If the microcomputer 31 detects the abnormality [1], one of the relays 27 to 29 is detected. The process of detecting any abnormality by turning on any one (that is, the process for detecting the OFF failure of the relays 27 to 29 and the disconnection of the monitor path Lm, the process of S180 to S340 in FIG. 6 described later). Not implemented.

  This is because if the relay 27 or the relay 28 is turned on in a state where the abnormality [1] has occurred, an effective current flows unnecessarily through the coil 23a or the coil 19a, and such unnecessary energization is avoided. It is to do.

  Further, the fact that the abnormality [1] is detected means that both CM1 and CM2 when the three relays 27 to 29 are turned off as shown in the row of “inspection drive mode (1)” in FIG. Since both were high, it can be said that the monitor path Lm is not disconnected, and even if the relays 27 to 29 are turned on one by one, it is correct in terms of detecting an off failure of the relays 27 to 29. This is because the detection result cannot be obtained (that is, CM1 and CM2 remain high, and the combination of “CM1 = low, CM2 = high” indicating an off-failure of the relays 27 to 29 does not occur).

  Next, when the microcomputer 31 detects the abnormality [2], as a user caution process, the microcomputer 31 performs a process of giving a warning indicating that “the start circuit is short-circuited to the ground” to the vehicle user. 2] is stored in a non-volatile memory or the like (not shown in FIG. 5), and processing for prohibiting idle stop is performed.

The reason why the idle stop is prohibited when the abnormality [2] is detected is as follows.
Of the abnormality [2], if the pinion drive relay 27 or the motor drive relay 28 is on, the on / off of the upstream cut relay 29 controls the energization / non-energization of the coils 23a and 19a (and thus the starter). 13), but when the relay 29 is turned on, there is a possibility that the normal relay 29 may be turned on, and the coil 23a or the coil 19a is effective. As a result, the starter 13 is in an unnecessary operation abnormality.

  For this reason, even when abnormality [2] is detected, by prohibiting idle stop, the opportunity for the starter 13 to function is reduced, and even the normal upstream cut relay 29 will be on-failed. It is preventing.

  Strictly speaking, at the time of starting the engine, it is necessary to perform sequence control in which the motor 17 is operated after the pinion gear 21 is moved first. However, it cannot be distinguished which of the pinion drive relay 27 and the motor drive relay 28 is on, and if the motor drive relay 28 is on, the above sequence control cannot be performed. On the other hand, if abnormality [2] is caused by a ground short in the monitor path Lm, when the upstream cut relay 29 is turned on to make the starter 13 function, the line 16 of the battery voltage VB is There is also a problem that the ground line is short-circuited and, for example, a fuse provided in the line 16 is blown. Also, from the viewpoint of avoiding each inconvenience, when the abnormality [2] is detected, the idle stop is prohibited and the opportunity for the starter 13 to function is reduced.

  In addition, the microcomputer 31 detects the abnormality [2] in a state where the three relays 27 to 29 are driven to be turned off. Even when the abnormality [2] is detected, the microcomputer 31 also detects the abnormality [2]. Processing for detecting any abnormality by turning on any one of the above (that is, processing for detecting an OFF failure of the relays 27 to 29 and disconnection of the monitor path Lm, and processing of S180 to S340 in FIG. 6 described later) ) Is not implemented.

  This is because, in the abnormality [2], if the pinion drive relay 27 or the motor drive relay 28 is on, the above-described unnecessary energization state is caused when the upstream cut relay 29 is turned on. To avoid it.

  Further, the fact that the abnormality [2] is detected means that both CM1 and CM2 when the three relays 27 to 29 are turned off as shown in the row of “inspection drive mode (1)” in FIG. Since both were low, it can be said that the monitor path Lm is not disconnected, and even if the relays 27 to 29 are turned on one by one, it is correct in terms of detecting an off failure of the relays 27 to 29. This is because a detection result cannot be obtained (that is, a combination of “CM1 = low, CM2 = high” indicating an off failure of the relays 27 to 29 is not possible). Further, if the ground short of the monitor path Lm is occurring, turning on the upstream cut relay 29 causes a ground short of the battery voltage VB (short circuit between the battery voltage VB line 16 and the ground line). Therefore, it may not be preferable.

  Next, when the microcomputer 31 detects abnormality [3] (disconnection of the monitor route Lm), a warning indicating that the “monitor route (Lm) is disconnected” is issued as a user caution process. In addition, the abnormality information indicating that abnormality [3] has occurred is stored in a nonvolatile memory or the like (not shown in FIG. 5), and further, processing for prohibiting idle stop is performed.

The reason why the idle stop is prohibited when the abnormality [3] is detected is as follows.
That is, when the abnormality [3] is detected, it is not impossible to know any abnormality other than the monitor path Lm and there is no possibility that any of the relays 27 to 29 has an off failure. If any of the relays 27 to 29 has an off-failure, the starter 13 cannot function normally. Therefore, if the engine is automatically stopped by the idle stop control, the engine is automatically restarted thereafter. The vehicle cannot run on the road. Therefore, prohibiting idle stop prevents the vehicle from running on the road.

  Next, when the microcomputer 31 detects abnormality [4] (off failure of the upstream cut relay 29), a warning indicating that “the upstream cut relay (29) has failed off” is processed as a user caution process. While performing the process given to the user of the vehicle, the abnormality information indicating that the abnormality [4] has occurred is stored in a nonvolatile memory or the like (not shown in FIG. 5), and further, the idle stop is prohibited. Process.

  Further, when the microcomputer 31 detects an abnormality [5] (off failure of the pinion drive relay 27), a warning indicating that “the pinion drive relay (27) is off failure” is issued as a user caution process. And processing for giving an abnormality [5] to the non-volatile memory or the like (not shown in FIG. 5), and further for prohibiting the idle stop. I do.

  Similarly, when the microcomputer 31 detects an abnormality [6] (off failure of the motor drive relay 28), a warning indicating that “the motor drive relay (28) has failed off” is processed as a user caution process. In addition to performing processing given to the user of the vehicle, abnormality information indicating that abnormality [6] has occurred is stored in a non-volatile memory or the like (not shown in FIG. 5), and further, an idle stop is prohibited. Process.

  The reason why the idle stop is prohibited when any one of abnormality [4] to abnormality [6] is detected is that the starter 13 cannot function because any of the relays 27 to 29 is not turned on. In order to prevent the vehicle from running on the road.

Based on the above, next, a specific procedure of the abnormality detection process performed by the microcomputer 31 will be described with reference to the flowcharts of FIGS.
FIG. 6 is a flowchart showing the abnormality detection process. Note that, as described above, this abnormality detection processing is periodically executed, for example, immediately after the initial start of the engine is completed or during the operation of the engine. In addition, each flag that is set to “1” on the ON side by this abnormality detection process is reset to “0” on the OFF side, for example, by an initialization process (not shown) executed when the microcomputer 31 is activated. .

  As shown in FIG. 6, when the microcomputer 31 starts the abnormality detection process, first, in S110, the three relays 27 to 29 are turned off to create the state of the inspection drive mode (1) shown in FIG. (Driving to turn off).

  That is, for the relays 27 and 28, by outputting a drive signal to the transistors T1 and T2 at an inactive level that turns off the transistors, the transistors T1 and T2 are turned off, whereby the relays 27 and 28 are output. Turn off. Further, the relay 29 is turned off by giving a command to the microcomputer 41 of the ECU 12 to turn off the transistor T3. As a control process of the starter 13, the relays 27 to 29 are originally turned off while the engine is operating.

Next, in S120, the outputs CM1 and CM2 of the comparators 51 and 52 are read, and it is determined whether or not “CM1 = low, CM2 = high”.
If “CM1 = low, CM2 = high” is not satisfied (S120: NO), it is considered that one of the above-described abnormalities [1] and [2] has occurred (“inspection drive in FIG. 4). In order to specify the abnormality that has occurred (see the line of mode (1)), the process proceeds to S130.

  In S130, it is determined whether or not “CM1, CM2 = high”. If “CM1, CM2 = high”, it is determined that an abnormality [1] has occurred (specified), and S140. Proceed to In S140, the flag F1 indicating that the abnormality [1] is detected is set to “1” on the ON side, and then the process proceeds to S350.

  If it is determined in S130 that “CM1, CM2 = high” is not established, the process proceeds to S150 to determine whether “CM1, CM2 = low”, and “CM1, CM2 = If “low”, it is determined (identified) that the abnormality [2] has occurred, and the process proceeds to S160. In S160, the flag F2 indicating that the abnormality [2] is detected is set to “1” on the ON side, and then the process proceeds to S350.

  If it is determined in S150 that “CM1, CM2 = low” is not satisfied, a diagnosis circuit (specifically, resistor R1) is a circuit for detecting abnormality [1] to abnormality [6]. , R2 and the voltage monitor circuit 50), the process proceeds to S170. In S170, the flag Fer indicating that the abnormality of the diagnosis circuit is detected is set to “1” on the ON side, and then the process proceeds to S350.

  That is, if “NO” is determined in S150, the combination of CM1 and CM2 when the three relays 27 to 29 are turned off is shown in the row of “inspection drive mode (1)” in FIG. Therefore, it is determined that the diagnosis circuit is abnormal.

  On the other hand, if it is determined in S120 that “CM1 = low, CM2 = high”, there is a possibility that either normal or abnormal [3] to [6] has occurred. (Refer to the row of “inspection drive mode (1)” in FIG. 4), the processing after S180 is performed in order to identify it.

  First, in S180, in order to make the state of the inspection drive mode (2) shown in FIG. 4, among the relays 27 to 29, only the pinion drive relay 27 is turned on while the relays 28 and 29 are kept off ( Drive to turn on). That is, the pinion drive relay 27 is turned on by turning on the transistor T1 by outputting a drive signal to the transistor T1 at an active level that turns on the transistor.

Next, in S190, the outputs CM1 and CM2 of the comparators 51 and 52 are read, and it is determined whether or not “CM1, CM2 = low”.
If “CM1, CM2 = low” is not satisfied (S190: NO), it is determined that the state is not normal and the process proceeds to S200.

  In S200, it is determined whether or not “CM1 = low, CM2 = high”. If “CM1 = low, CM2 = high”, as described above, one of abnormalities [3] and [5] is detected. (See the row of “Driving drive mode for inspection (2)” in FIG. 4), the process proceeds to S210, and the flag F3 indicating that the abnormality [3] is detected and the abnormality [5] ] Is set to "1" on the ON side, and then the process proceeds to S230, which of the abnormal [3] and [5] has occurred in the later processing. Identified.

  If it is determined in S200 that “CM1 = low, CM2 = high”, it is determined that an abnormality has occurred in the diagnosis circuit, and the process proceeds to S220. In S220, as in S170, the flag Fer is set to “1”, and then the process proceeds to S350.

  In other words, at this time, it is determined as “YES” in S120 and it is confirmed that the abnormality [1] has not occurred, and therefore CM1 and CM2 have a combination of “CM1, CM2 = high”. Instead, it should be a combination of “CM1, CM2 = low” and “CM1 = low, CM2 = high” (see the row of “inspection drive mode (2)” in FIG. 4). However, if “NO” is determined in S200, it means that neither “CM1, CM2 = low” nor “CM1 = low, CM2 = high”, and an abnormality occurs in the diagnosis circuit. Judging.

  On the other hand, if it is determined in S190 that “CM1, CM2 = low”, the process directly proceeds to S230. In this case (in the case of directly proceeding from S190 to S230), there is a possibility that either normal or abnormal [4], [6] has occurred.

  In S230, the pinion drive relay 27 is turned off and then the motor drive relay 28 is turned on in order to create the state of the inspection drive mode (3) shown in FIG. That is, the pinion drive relay 27 is turned off by switching the drive signal to the transistor T1 to the inactive level and turning the transistor T1 off, and then the drive signal to the transistor T2 is switched to the active level and the transistor T2 is turned on. By turning it on, the motor drive relay 28 is turned on. For this reason, only the motor drive relay 28 among the relays 27 to 29 is turned on.

Next, in S240, the outputs CM1 and CM2 of the comparators 51 and 52 are read, and it is determined whether or not “CM1, CM2 = low”.
If “CM1, CM2 = Low” is not satisfied (S240: NO), it is determined that the state is not normal at least, and the process proceeds to S250.

  In S250, it is determined whether or not “CM1 = low, CM2 = high”. If “CM1 = low, CM2 = high”, as described above, one of abnormalities [3] and [6] is determined. (See the row of “Driving drive mode for inspection (3)” in FIG. 4), the process proceeds to S260, and the flag F3 indicating that the abnormality [3] is detected and the abnormality [6] ] Is set to "1" on the ON side, and then the process proceeds to S270, which of the abnormal [3] and [6] has occurred in later processing. Identified.

  If it is determined in S250 that “CM1 = low, CM2 = high”, it is determined that an abnormality has occurred in the diagnosis circuit, and the process proceeds to S220 described above, and the flag Fer is set to “1”. Then, the process proceeds to S350.

  That is, as in the case where “NO” is determined in S200, since it has been confirmed that no abnormality [1] has occurred at this time, CM1 and CM2 have a combination of “CM1, CM2 = high”. And cannot be a combination of “CM1, CM2 = low” and “CM1 = low, CM2 = high” (see the row of “inspection drive mode (3)” in FIG. 4). ). However, if “NO” is determined in S250, it means that neither “CM1, CM2 = low” nor “CM1 = low, CM2 = high”, and an abnormality occurs in the diagnosis circuit. Judging.

  On the other hand, if it is determined in S240 that “CM1, CM2 = low”, the process proceeds to S270 as it is. In this case (in the case of directly proceeding from S240 to S270), there is a possibility that either normal or abnormal [4], [5] has occurred.

  In S270, the motor drive relay 28 is turned off and then the upstream cut relay 29 is turned on in order to create the state of the inspection drive mode (4) shown in FIG. That is, by switching the drive signal to the transistor T2 to the inactive level and turning off the transistor T2, the motor drive relay 28 is turned off, and then a command is given to the microcomputer 41 of the ECU 12 to turn on the transistor T3. The upstream cut relay 29 is turned on. For this reason, only the upstream cut relay 29 among the relays 27 to 29 is turned on.

Next, in S280, the outputs CM1 and CM2 of the comparators 51 and 52 are read, and it is determined whether or not “CM1, CM2 = high”.
If it is not “CM1, CM2 = high” (S240: NO), it is determined that it is not normal, and the process proceeds to S290.

  In S290, it is determined whether or not “CM1 = low, CM2 = high”. If “CM1 = low, CM2 = high”, either abnormality [3] or [4] has occurred. Therefore (see the row of “Driving mode for inspection (4)” in FIG. 4), the process proceeds to S300 in order to identify the abnormality that has occurred.

  In S300, it is determined whether or not the flag F3 is “1”. If the flag F3 is “1”, the abnormality [3] of the abnormality [3] and [4] is determined. Is determined (specified), the process proceeds to S310, and the flags F5 and F6 are set to "0". Then, the process proceeds to S350.

  That is, in this case, the flag F3 is set to “1” in at least one of S210 and S260 (actually both), and only the relay 29 among the three relays 27 to 29 is set. “CM1 = low” not only when the relay 27 is turned on but also when at least one of the relay 27 and the relay 28 are turned on (actually considered to be both). , CM2 = high ”. Therefore, as described above, since at least two of the three relays 27 to 29 are turned on one by one, “CM1 = low, CM2 = high” is obtained. Instead of [4] (off failure of upstream cut relay 29), it is determined that abnormality [3] (disconnection of monitor path Lm) has occurred (see column (f) in FIG. 4).

  Furthermore, since the abnormality [3] means that the abnormality is not [5] or [6], the flag F5 and the flag F6 that were set to “1” in S210 and S260 are changed to S310. To “0”. That is, the abnormality [3] and the abnormality [5] cannot be discriminated at the execution stage of S210, and similarly, the abnormality [3] and the abnormality [6] cannot be discriminated at the execution stage of S260. It is possible to specify that the abnormality [3] is occurring at the execution stage of.

  On the other hand, if it is determined in 300 above that the flag F3 is not “1”, it is determined (specifically) that the abnormality [4] is occurring instead of the abnormality [3]. Proceeding to S320, the flag F4 indicating that the abnormality [4] has been detected is set to "1" on the on side. Then, the process proceeds to S350.

  That is, in this case, even if each of the relays 27 and 28 among the three relays 27 to 29 is turned on, “CM1 = low, CM2 = high” is not satisfied, but only when the relay 29 is turned on. Since “CM1 = low, CM2 = high”, it is determined that an abnormality [4] has occurred instead of an abnormality [3] (see the column (g) in FIG. 4). reference).

  Eventually, as described above, the microcomputer 31 verifies CM1 and CM2 in each case where the three relays 27 to 29 are turned on one by one, and “CM1 = low, CM2 = high” only in any one case. ”, It is determined that the relay that was turned on when“ CM1 = low, CM2 = high ”(upstream cut relay 29 in this example) has an off failure.

  If it is determined in S290 that “CM1 = low, CM2 = high”, it is determined that an abnormality has occurred in the diagnosis circuit, the process proceeds to S220 described above, and the flag Fer is set to “1”. Then, the process proceeds to S350.

  In other words, at this time, it is determined as “YES” in S120 and it is confirmed that the abnormality [2] has not occurred, so CM1 and CM2 have a combination of “CM1, CM2 = low”. Instead, it should be a combination of “CM1, CM2 = high” and “CM1 = low, CM2 = high” (refer to the row of “inspection drive mode (4)” in FIG. 4). However, if “NO” is determined in S290, it means that neither “CM1, CM2 = high” nor “CM1 = low, CM2 = high”, and an abnormality occurs in the diagnosis circuit. Judging.

  On the other hand, if it is determined in S280 that “CM1, CM2 = high”, the process proceeds to S330. In this case (in the case of proceeding from S280 to S330), there is a possibility that either normal or abnormal [5], [6] has occurred.

  In S330, it is determined whether or not the flag F5 or the flag F6 is “1”. If the flag F5 or the flag F6 is “1”, the flag corresponding to the flag that is “1” is determined. It is determined that an abnormality has occurred (that is, if flag F5 is “1”, abnormality [5] has occurred, and if flag F6 is “1”, abnormality [6] has occurred) ( Specify) and proceed to S340 and set the flag F3 to "0". Then, the process proceeds to S350.

  That is, the flag F5 is set to “1” in S210 and the flag F6 is set to “1” in S260. As described above, in the execution stage of S210, the abnormality [3] and abnormality [5] Similarly, in the execution stage of S260, the flag [F3] is also set to “1” because it is not possible to determine whether the error [3] is abnormal [6].

  However, in the execution stage of S340, “YES” is determined in S280, and when only the relay 29 of the three relays 27 to 29 is turned on, CM1 and CM2 are the same as when “CM1, CM2 = normal”. Since “high” is confirmed, it is determined that the occurrence is not abnormality [3] but abnormality [5] or abnormality [6]. For this reason, in S340, the flag F3 is returned to “0”, and the flag F5 and the flag F6 that are “1” remain “1” and are enabled.

  Therefore, when only the pinion drive relay 27 is turned on among the three relays 27 to 29, even if the flag F3 and the flag F5 are set to “1”, “CM1 = low, CM2 = high”. (S200: YES → S210) When only the upstream cut relay 29 is turned on, if CM1 and CM2 become “CM1, CM2 = high” that is normal (S280: YES), the flag F3 is “0”. (S340), only the flag F5 remains “1”. Similarly, when only the motor drive relay 28 is turned on among the three relays 27 to 29, “CM1 = low, CM2 = high”, and the flags F3 and F6 are set to “1”. (S250: YES → S260), when only the upstream cut relay 29 is turned on, if CM1 and CM2 become “CM1, CM2 = high” that is normal (S280: YES), the flag F3 is “0”. (S340), only the flag F6 remains "1".

  Eventually, as described above, the microcomputer 31 verifies CM1 and CM2 in each case where the three relays 27 to 29 are turned on one by one. In either case, “CM1 = low, CM2 = high”. In any other case, if CM1 and CM2 are at the same logic level as normal, the relay turned on when “CM1 = low, CM2 = high” (in this example, a pinion drive relay) 27 or the motor drive relay 28) is determined to be off-failed.

  On the other hand, if it is determined in S330 that both the flag F5 and the flag F6 are not “1” (S330: NO), it is determined that there is no abnormality (that is, normal), and the process directly proceeds to S350.

In S350, the same processing as S110 is performed to turn off the three relays 27 to 29.
Then, in the next S360, the fail safe process shown in FIG. 7 is executed.

  As shown in FIG. 7, when the fail safe process is started, the microcomputer 31 first determines whether or not the flag F1 is “1” in S410. If the flag F1 is “1”, the microcomputer 31 proceeds to S420. move on. In S420, as a process of user caution when abnormality [1] is detected, as described above, a process of giving a warning to the user of the vehicle that the “starting circuit is short-circuited” is performed. , The process proceeds to S550.

  If it is determined in S410 that the flag F1 is not “1”, the process proceeds to S430, where it is determined whether the flag F2 is “1”, and the flag F2 is “1”. If there is, the process proceeds to S440. In S440, as a process of user caution when the abnormality [2] is detected, as described above, a process of giving a warning to the vehicle user that “the start circuit is short-circuited” is performed. , The process proceeds to S550.

  If it is determined in S430 that the flag F2 is not “1”, the process proceeds to S450 to determine whether or not the flag F3 is “1”, and the flag F3 is “1”. If there is, the process proceeds to S460. In S460, as a process of user caution when the abnormality [3] is detected, as described above, a process of giving a warning to the vehicle user indicating that “the monitor route (Lm) is disconnected” is performed. Thereafter, the process proceeds to S550.

  If it is determined in S450 that the flag F3 is not “1”, the process proceeds to S470 to determine whether or not the flag F4 is “1”, and the flag F4 is “1”. If there is, the process proceeds to S480. In S480, as a user caution process when abnormality [4] is detected, as described above, a process of giving a warning to the user of the vehicle that “the upstream cut relay (29) has failed” Then, the process proceeds to S550.

  If it is determined in S470 that the flag F4 is not “1”, the process proceeds to S490 to determine whether or not the flag F5 is “1”, and the flag F5 is “1”. If there is, the process proceeds to S500. In S500, as a process of user caution when the abnormality [5] is detected, as described above, a process of giving a warning to the vehicle user indicating that “the pinion drive relay (27) is off-failed” Then, the process proceeds to S550.

  If it is determined in S490 that the flag F5 is not “1”, the process proceeds to S510 to determine whether or not the flag F6 is “1”, and the flag F6 is “1”. If there is, the process proceeds to S520. In S520, as a user caution process when abnormality [6] is detected, as described above, a process of giving a warning to the vehicle user indicating that “the motor drive relay (28) is off-failed” Then, the process proceeds to S550.

  If it is determined in S510 that the flag F6 is not “1”, the process proceeds to S530 to determine whether or not the flag Fer is “1”, and the flag Fer is “1”. If there is, the process proceeds to S540. In S540, as a user caution process when an abnormality of the diagnosis circuit is detected, a process of giving a warning indicating that the diagnosis circuit is abnormal to the vehicle user is performed, and then the process proceeds to S550.

Therefore, if any of the flags F1 to F6 and Fer is “1” and an abnormality corresponding to the flag “1” is detected, the process proceeds to S550.
In S550, a process for prohibiting idle stop is performed. Specifically, as described above, the idle stop prohibition flag is set. Then, the fail safe process is terminated. Then, the abnormality detection process in FIG. 6 is also ended.

  That is, in the fail-safe process of FIG. 7, when any one of abnormality [1] to abnormality [6] or abnormality of the diagnosis circuit is detected, user caution is performed according to the detected abnormality and idle stop is performed. Is prohibited.

  The reason why the idle stop is prohibited when any one of abnormality [1] to abnormality [6] is detected is as described with reference to FIG. Also, when an abnormality of the diagnosis circuit is detected, the idle stop is prohibited if the diagnosis circuit is not normal and the circuit for causing the starter 13 to function (the energization circuit for the coils 19a and 23a) is normal. This is because there is a possibility that the starter 13 cannot be functioned.

  On the other hand, if it is determined in S530 that the flag Fer is not “1”, the flags F1 to F6 and Fer are all “0”, it is determined that there is no abnormality, and the fail-safe process is terminated as it is. To do. Then, the abnormality detection process in FIG.

  The microcomputer 31 refers to the flags F <b> 1 to F <b> 6 and Fer by another abnormality information storage process, and if there is a flag “1”, the abnormality information indicating that the abnormality indicated by the flag has occurred ( A so-called diagnostic code) is stored in a nonvolatile memory or the like. The abnormality information stored in the nonvolatile memory or the like can be read out by a failure diagnosis device (so-called scan tool) connected to the ECU 11 so as to be communicable.

  According to the starter control device of the present embodiment including the two ECUs 11 and 12 and the three relays 27 to 29 as described above, the upstream cut relay 29 and the pinion in series with respect to the coil 23a of the pinion control solenoid 23 are provided. As long as both the drive relay 27 and the drive relay 27 are not on-failed, they will not fall into an unnecessary energized state. Similarly, the coil 19a of the electromagnetic switch 19 does not fall into an unnecessary energized state unless both the upstream cut relay 29 and the motor drive relay 28 in series with each other are turned on.

  That is, even if one of the two relays in series fails to turn on, if the other is not turned on, it is possible to prevent an effective current from flowing through each of the coils 23a and 19a. It is possible to prevent an unnecessary operation abnormality in which the 13 pinion gears 21 or the motor 17 operate unnecessarily.

  Furthermore, since it is possible to detect an on-failure of each of the relays 27 to 29, there is an increased possibility that an unnecessary energization state to the coil 23a or the coil 19a (and hence an abnormal operation abnormality of the starter 13) will occur. By detecting this, fail-safe treatment can be performed in advance. Specifically, if any of the relays 27 to 29 is turned on (abnormality [1] or abnormality [2]), the starter 13 must be functioned because idle stop is prohibited. It is possible to reduce the chances that have to be avoided and prevent even normal relays from failing on. Therefore, the reliability of the apparatus can be improved.

  Moreover, since the OFF failure of each relay 27-29 can also be detected, the reliability of the apparatus can be further improved. Specifically, when an off-fault of any one of the relays 27 to 29 (any one of abnormalities [4] to [6]) is detected, idle stop is prohibited. It can be prevented in advance that the engine cannot be restarted and the vehicle cannot travel on the road.

  In addition, when detecting an OFF failure of the relays 27 to 29, as a measure for preventing the necessity of causing the starter 13 to function, in addition to prohibiting idle stop, for example, for the driver of the vehicle Thus, a process for prompting the engine not to be stopped may be performed. As the process, as described above, a process for outputting a message indicating that the engine should not be stopped by sound or displaying it on a display device can be considered. Also, for example, if the vehicle stops the engine when the push-type start button is kept pressed, the effective determination time from when the button starts to be pressed until the engine is stopped is changed to a time longer than the normal value. But it ’s okay. And if such a process is performed, it can also prevent that a driver | operator stops an engine by one's own intention, and can further improve the prevention effect that a vehicle becomes impossible to drive | working by extension. .

  Further, in the abnormality detection process of FIG. 6, when abnormality [1] or abnormality [2] is detected by the processes of S110 to S160, and any on failure of the relays 27 to 29 is detected. Does not perform the processing of S180 to S340 for detecting the on failure of the relays 27 to 29. For example, in the state where the relay 29 is on, the relay 27 or 28 is turned on to detect an abnormality. Conversely, the relay 29 is not turned on for abnormality detection in a state where either of the relays 27 and 28 is on. For this reason, it is possible to reliably prevent an effective current from flowing unnecessarily through the coil 23a or the coil 19a by performing the abnormality detection process of FIG.

  On the other hand, in this embodiment, each of the coil 23a of the pinion control solenoid 23 and the coil 19a of the electromagnetic switch 19 corresponds to an electric load for causing the starter to function, and the ground voltage corresponds to the first potential. The battery voltage VB corresponds to the second potential.

  Regarding the coil 23a, the upstream cut relay 29 and the pinion drive relay 27 correspond to energizing switch means provided in the current path to the coil 23a, and the upstream cut relay 29 is a non-load side switch. The pinion drive relay 27 corresponds to the load side switch means. With respect to the coil 19a, the upstream cut relay 29 and the motor drive relay 28 correspond to energizing switch means provided in the current path to the coil 19a, of which the upstream cut relay 29 is the non-load side switch. The motor drive relay 28 corresponds to the load side switch means.

  Further, the voltage monitor circuit 50 and the microcomputer 31 correspond to abnormality detection means, and the microcomputer 31 also corresponds to idle stop control means. Further, the resistor R2 corresponds to a first resistance component, and the resistor R1 corresponds to a second resistance component.

  Further, the processing of S110 to S160 in FIG. 6 corresponds to the off-drive abnormality detection process, and the processing of S180 to S210 in FIG. 6 corresponds to the on-drive abnormality detection process using the pinion drive relay 27 as the specific switch means. 6 corresponds to the on-drive abnormality detection process using the motor drive relay 28 as the specific switch means, and the processes from S270 to S340 in FIG. 6 specify the upstream cut relay 29 as the specific switch means. This corresponds to the on-drive abnormality detection process.

  Further, assuming that the coil 23a is a first electric load and the coil 19a is a second electric load, the pinion drive relay 27 corresponds to the first load side switch means, and the motor drive relay 28 is the second load. 6 corresponds to the first load side switch means on-time abnormality detection process, and the processes of S230 to S260 in FIG. This corresponds to the abnormality detection process when the load side switch means is turned on.

  In the abnormality detection process of FIG. 6, the disconnection of the monitor path Lm is detected separately from the OFF fault of the relays 27 to 29. However, the disconnection of the monitor path Lm is detected as the OFF fault of the relays 27 to 29. It may be detected. In this case, in the abnormality detection process of FIG. 6, when flag F3 is not set to “1” in each of S210 and S260, S300, S310, S330, and S340 are further deleted, and “YES” is determined in S280. The process proceeds to S350, and if “YES” is determined in S290, the process may be modified to proceed to S320.

[Second Embodiment]
As shown in FIG. 8, in the second embodiment, compared to the first embodiment, a starter 63 is employed in place of the starter 13, and the starter 63 engages the operation of meshing the pinion gear 21 with the ring gear 25, and the motor. The operation of 17 is a type that is performed in conjunction with each other. That is, the starter 63 cannot operate the pinion gear 21 and the motor 17 independently. However, the number of times that the pinion gear 21 and the motor 17 and the like can be used is increased by increasing the number of times that the pinion gear 21 and the motor 17 can be used rather than those mounted on a vehicle in which idle stop is not performed.

  More specifically, in the starter 63, when the coil 23a of the pinion control solenoid 23 is energized, not only the pinion gear 21 protrudes and meshes with the ring gear 25, but also the electromagnetic switch by the electromagnetic force generated by energizing the coil 23a The 19 contacts 19b and 19c are short-circuited, and the energization path from the battery 15 to the motor 17 is communicated.

  For this reason, the electromagnetic switch 19 of the starter 63 does not have the coil 19a of the first embodiment, and the relay 28 for energizing the coil 19a is not provided outside the ECU 11. Accordingly, the transistor T2 for turning on the relay 28 is not provided in the ECU 11.

  That is, in the second embodiment, the coil 23a of the pinion control solenoid 23 is an electric load that operates both the pinion gear 21 and the motor 17 (an electric load for causing the starter 63 to function). The pinion drive relay 27 can actually be said to be a pinion and motor drive relay, and can also be said to be a starter relay for causing the starter 63 to function.

  The other hardware configuration is the same as that of the first embodiment. In FIG. 8, the same components as those shown in FIG. 1 are denoted by the same symbols as those used in FIG. Therefore, the description is omitted.

  From the above, in the second embodiment, the combination of the content of the abnormality detected by the microcomputer 31 of the ECU 11, the driving state of the relays 27 and 29, and the outputs CM1 and CM2 of the comparators 51 and 52 is shown in FIG. As shown.

  That is, in FIG. 9, compared to FIG. 4 showing the combination in the case of the first embodiment, the contents relating to the motor drive relay 28 are deleted. Specifically, the row of the test drive mode (3) is There is no column of (d) and (i). In the second embodiment, the abnormality [2] means an ON failure of the pinion drive relay 27 or a ground short of the monitor path Lm, and of course, abnormality [6] (motor drive relay 28 There is no off failure.

Then, the microcomputer 31 of the ECU 11 executes the abnormality detection process of FIG. 10 instead of the abnormality detection process of FIG.
Compared with the abnormality detection process of FIG. 6, the abnormality detection process of FIG. 10 is a process in which the process related to the motor drive relay 28 is deleted, and specifically, the following points are different.

First, in S115 instead of S110, the two relays 27 and 29 are turned off.
Secondly, S230 to S260 are deleted.
Third, in S275 instead of S270, the pinion drive relay 27 that was turned on in S180 is turned off, and then the upstream cut relay 29 is turned on.

Fourth, the flag F6 is not provided and only the flag F5 is set to “0” in S315 instead of S310.
Fifth, in S335 instead of S330, it is determined whether or not the flag F5 is “1”.

Sixth, in S355 instead of S350, the two relays 27 and 29 are turned off as in S115.
Seventhly, in S365 instead of S360, the fail-safe process of FIG. 11 is executed.

  The fail-safe process of FIG. 11 is modified so that the process proceeds to S530 when S510 and S520 are deleted and “NO” is determined in S490, compared to the fail-safe process of FIG. .

  However, as described above, in the second embodiment, since it can be said that the pinion drive relay 27 is a starter relay, in the fail-safe process of FIG. 11, in S500 that proceeds when the flag F5 is “1”, As a user caution process, a process of giving a warning to the user of the vehicle indicating that “the starter relay is off-failed” may be performed.

The second embodiment as described above can achieve the same effects as those of the first embodiment except that the coil 19a and the motor drive relay 28 are not provided.
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to such Embodiment at all, Of course, in the range which does not deviate from the summary of this invention, it can implement in a various aspect. .

  For example, the motor 17 can be regarded as an electric load for causing the starter to function. In this case, the electromagnetic switch 19 is used as a load-side switch means, and the upstream side of the electromagnetic switch 19 in the energization path to the motor 17. In addition, a relay having an energization capability equivalent to that of the electromagnetic switch 19 may be provided as the non-load side switch means.

  In the above-described embodiment, the low potential side of the high potential side (battery voltage VB) and the low potential side (ground voltage) of the power source is set to the first potential, that is, the electrical load to be energized. Although a high-side drive configuration is provided in which a relay as an energization switch means is provided on the upstream side, the higher potential side of the power source may be set as the first potential. That is, a low-side drive configuration in which the energizing switch means is provided downstream of the electric load to be energized may be employed.

  For example, in FIG. 1, one end of the coil 23a and the coil 19a is connected to the line 16 of the battery voltage VB, and the terminal 29b of the relay 29 is connected to the ground line, so that “battery voltage VB → coil 23a → relay 27 → A current may flow through each of the coils 23a and 19a through a path of “relay 29 → ground line” and a path of “battery voltage VB → coil 19a → relay 28 → relay 29 → ground line”.

Further, at least one of the relays 27 to 29 may be mounted on any of the ECUs 11 and 12.
1, the terminal 28b of the relay 28 is disconnected from the terminal 29c of the relay 29, and the terminal 28b of the relay 28 is connected to the line 16 of the battery voltage VB via another relay provided separately from the relay 29. It may be configured as described above. That is, one set of two relays in series may be provided for each of the coils 23a and 19a.

The energization switch means is not limited to a mechanical relay, and a switch made of a semiconductor such as a transistor may be used.
Moreover, you may comprise ECU11 and ECU12 as one unit.

DESCRIPTION OF SYMBOLS 11, 12 ... ECU (electronic control unit), 13, 63 ... Starter 14 ... Battery voltage monitor terminal, 15 ... Battery, 16 ... Battery voltage line 17 ... Motor, 19 ... Electromagnetic switch, 19a ... Coil, 19b, 19c ... Contact 21 ... Pinion gear, 25 ... Engine ring gear 23 ... Pinion control solenoid, 23a ... Coil 27 ... Pinion drive relay, 27a ... Coil, 27b, 27c ... Terminal,
28 ... motor drive relay, 28a ... coil, 28b, 28c ... terminal,
29 ... Upstream cut relay, 29a ... Coil, 29b, 29c ... Terminal,
31, 41 ... microcomputer, 33 ... input circuit, 39 ... capacitor, 43 ... communication line 35, 37, 53-58, R1, R2, ... resistance, 50 ... voltage monitor circuit 51, 52 ... comparator, Lm ... abnormality detection Wiring (monitor path), J1 to J4 ... terminals T1 to T3 ... transistors

Claims (6)

One end of an electric load for functioning a starter for cranking the engine for starting is used in a vehicle connected to a first potential which is one of a high potential side and a low potential side of a power source,
Energization switch means provided in a current path between a second potential that is different from the first potential on the high potential side and the low potential side of the power source and the other end of the electrical load; A starter control device that causes the starter to function by causing a current to flow through the electrical load by turning on and communicating the current path;
As the energizing switch means,
Non-load-side switch means in which one of the pair of terminals that are short-circuited by turning on is connected to the second potential;
One terminal of the pair of terminals that are short-circuited by being turned on is connected to a terminal opposite to the second potential side of the non-load side switch means, and the other terminal is connected to the other of the electric load. Load side switch means connected to the end,
Further, the voltage of the inter-switch path, which is a current path between the non-load side switch means and the load side switch means, in a state where the non-load side switch means and the load side switch means are driven to be turned off. And an abnormality detection means for performing an off-drive abnormality detection process for detecting an on-failure of any of the non-load side switch means and the load side switch means based on the voltage ,
The abnormality detection means includes
The specific switch means which is one of the non-load side switch means and the load side switch means is driven to turn on, and the non-load side switch means and the load side switch means are Other than the specific switch means, the voltage of the path between the switches is monitored while being driven to turn off, and on-drive abnormality detection processing for detecting an off failure of the specific switch means is performed based on the voltage,
The vehicle is provided with two electric loads, a first electric load and a second electric load, each of which is energized independently as the electric load, and the starter includes two electric loads. It functions by energizing an electrical load,
The starter control device
The load side switch means includes two switch means, a first load side switch means and a second load side switch means,
Of the pair of terminals of the first load side switch means, one terminal is connected to a terminal opposite to the second potential side of the non-load side switch means, and the other terminal is connected to the first terminal. Is connected to an end of the electrical load opposite to the first potential side,
Of the pair of terminals of the second load side switch means, one terminal is connected to a terminal opposite to the second potential side of the non-load side switch means, and the other terminal is the second terminal. Is connected to an end of the electrical load opposite to the first potential side,
Further, the abnormality detection means includes
As the on-drive abnormality detection process using the load side switch means as the specific switch means,
The first load side switch means is driven to be turned on, and the non-load side switch means and the second load side switch means are driven to be turned off. A first load-side switch means on-drive abnormality detection process for monitoring a voltage and detecting an off failure of the first load-side switch means based on the voltage;
The second load side switch means is driven to be turned on, and the non-load side switch means and the first load side switch means are driven to be turned off. A second load side switch means on-drive abnormality detection process for monitoring a voltage and detecting an off failure of the second load side switch means based on the voltage;
Performing the starter control apparatus according to claim. The starter control device according to claim 1,
The vehicle is provided with idle stop control means for stopping the engine when a predetermined automatic stop condition is satisfied, and then restarting the engine when a predetermined automatic start condition is satisfied,
The starter control device is configured to cause the starter to function by turning on the energizing switch means when the idle stop control means restarts the engine.
Further, the starter control device is configured such that when the on-failure of any of the non-load side switch means and the load side switch means is detected by the abnormality detection means, the idle stop control means performs the engine stop operation. Prohibiting it from being stopped,
A starter control device. In the starter control device according to claim 1 or 2 ,
The abnormality detection means includes
In order to detect an off-fault of each of the non-load side switch means and the load side switch means, each of the non-load side switch means and the load side switch means is used as the specific switch means, and the abnormality detection during the ON drive is performed. Processing,
A starter control device. The starter control device according to any one of claims 1 to 3 ,
The abnormality detection means includes
If any of the non-load-side switch means and the load-side switch means is detected by the off-drive abnormality detection process, the on-drive abnormality detection process is not performed.
A starter control device. The starter control device according to any one of claims 1 to 4,
The vehicle is provided with idle stop control means for stopping the engine when a predetermined automatic stop condition is satisfied, and then restarting the engine when a predetermined automatic start condition is satisfied,
The starter control device is configured to cause the starter to function by turning on the energizing switch means when the idle stop control means restarts the engine.
Further, the starter control device is configured such that when the off-failure of either the non-load side switch unit or the load side switch unit is detected by the abnormality detection unit, the idle stop control unit performs the engine stop operation. Prohibiting it from being stopped,
A starter control device. The starter control device according to any one of claims 1 to 5 ,
A first resistance component connected between the first potential and the inter-switch path; and a second resistance component connected between the second potential and the inter-switch path. about,
A starter control device.

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