JP5533916B2 - 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.

  In recent years, in a vehicle (automobile), the engine is automatically stopped when a predetermined automatic stop condition is satisfied, and then the engine is automatically started (so-called restart) when a predetermined automatic start condition is satisfied. A system having a starting system (generally called an idle stop (or idling stop) system) has been put into practical use (see, for example, Patent Document 1).

  In addition, in a vehicle equipped with an idle stop system (hereinafter referred to as a vehicle equipped with an idle stop system), two energization circuits for energizing an electric load provided in the starter to operate the starter are provided in parallel. (For example, refer to Patent Document 1).

  One energization circuit is not for the idling stop system, but energizes the electric load when the user starts to start the engine in response to a start operation performed by the vehicle driver to start the engine. It is a user starting circuit to be operated. The other energization circuit is for the idle stop system, and is an automatic start circuit for energizing the electric load and operating the starter when the automatically stopped engine is automatically started. The reason why the user starting circuit is provided separately from the automatic starting circuit is to ensure that the user starting can be surely performed by the user starting circuit even when the power supply voltage is low.

JP 2010-90874 A

  By the way, in the vehicle equipped with the idle stop system, before the engine is automatically stopped, it is determined whether or not the automatic start circuit is normal. If it is determined that the circuit is not normal (abnormal), the engine is automatically stopped. It is conceivable not to do so. This is because the engine cannot be started automatically.

  However, an abnormality may occur in the automatic starting circuit after the engine is automatically stopped. For this reason, there may be a case where the starter cannot be operated by the automatic start circuit after the engine is automatically stopped (that is, the engine cannot be automatically started). In that case, the driver of the vehicle can only start the engine by performing a starting operation.

  Therefore, an object of the present invention is to prevent the automatic start of the engine from being disabled.

A vehicle in which the starter control device of the present invention is used includes a starter, a first energizing unit, an automatic stopping unit, and a second energizing unit different from the first energizing unit.
The starter operates by energizing an electric load provided in the starter, and cranks the engine to start the engine of the vehicle. The first energization means operates the starter by energizing the electric load of the starter when the driver of the vehicle performs a start operation for starting the engine. The automatic stop means stops the engine when a predetermined automatic stop condition is satisfied during operation of the engine. The second energization means operates the starter by energizing the electric load when a drive signal is given.

  The start operation is a manual operation performed by the driver to start the engine. For example, an operation for twisting the vehicle key inserted into the ignition key cylinder to the start position, or a push for starting the engine. For example, an operation of turning on a switch (a switch that is turned on when the button is pressed) is performed.

The starter control device of the present invention includes condition determining means, normal control means, abnormality determining means, and abnormality control means.
The condition determination means determines whether or not an automatic start condition for automatically starting the engine is satisfied after the engine is stopped by the automatic stop means.

  Then, the normal control means gives a drive signal to the second energizing means to energize the electric load when the condition judging means determines that the automatic start condition is satisfied. Thus, the starter is operated to start the engine.

The abnormality determination unit determines whether or not the second energization unit functions normally when the condition determination unit determines that the automatic start condition is satisfied.
When the abnormality determining means determines that the second energizing means does not function normally, the abnormality control means causes the first energizing means to energize the electric load, thereby operating the starter. Start the engine.

  That is, in this starter control device, when the automatic start condition is satisfied and the engine is automatically started, if the second energization means does not function normally, the first energization that is originally used at the time of user start is used. The engine is automatically started by causing the means to energize the electric load and operating the starter.

  For this reason, for example, even if an abnormality occurs in the second energizing unit after the engine is automatically stopped, and the automatic energizing condition is satisfied, the first energizing unit is abnormal. By operating the starter using the means, the engine can be started automatically. That is, it is possible to prevent the engine from being automatically started.

  In particular, the engine can be started without causing the vehicle driver to perform a starting operation. For this reason, among the automatic start conditions, conditions established other than the driver's action (for example, conditions that the battery voltage has become a predetermined value or less, conditions that the absolute value of the brake negative pressure has become a predetermined value or less, etc.) ), The engine can be automatically started without making the driver aware of it.

It is a block diagram showing ECU of 1st Embodiment and its peripheral device. It is a flowchart showing an automatic stop control process. It is a flowchart showing the automatic start control process of 1st Embodiment. It is the 1st explanatory view explaining operation of the 1st embodiment. It is the 2nd explanatory view explaining an operation of a 1st embodiment. It is the 3rd explanatory view explaining operation of the 1st embodiment. It is a block diagram showing ECU of 2nd Embodiment and its peripheral device. It is a flowchart showing the automatic start control process of 2nd Embodiment. It is a block diagram showing ECU of 3rd Embodiment and its peripheral device. It is a flowchart showing the automatic start control process of 3rd Embodiment.

Hereinafter, an electronic control device (hereinafter referred to as ECU) as a starter control device according to an embodiment to which the present invention is applied will be described.
[First Embodiment]
The ECU 11 of the first embodiment shown in FIG. 1 controls the starter 15 that cranks the engine 13 of the vehicle for starting. The ECU 11 automatically stops the engine 13 and the engine stopped by the control. Control to automatically start 13 is also performed. Here, the description will be made assuming that the transmission of the vehicle is an automatic transmission.

  The starter 15 includes a motor (starter motor) 17 serving as a power source for cranking the engine 13, a pinion gear 19 that is rotationally driven by the motor 17, and a switch provided in a current-carrying path from the battery 20 as a power source to the motor 17. 21 and a solenoid 23 for turning on the switch 21 while projecting the pinion gear 19 to a meshing position where the pinion gear 19 meshes with the ring gear 14 of the engine 13. The coil of the solenoid is called a solenoid.

  One end of the solenoid 23 is connected to the ground line. In the starter 15, when the other end (upstream side) of the solenoid 23 is applied with the battery voltage VB (about 12 V in the present embodiment) that is the voltage of the plus terminal of the battery 20, the solenoid 23 is energized. The electromagnetic force of the solenoid 23 causes the pinion gear 19 to protrude outward from the starter 15 and reach the meshing position with the ring gear 14, and the switch 21 is turned on (specifically, a pair of contacts 21a, 21b is short-circuited), and the energization path from the battery 20 to the motor 17 communicates. Then, the motor 17 is energized with the pinion gear 19 engaged with the ring gear 14, and the rotational force of the motor 17 is transmitted to the ring gear 14 via the pinion gear 19, and the engine 13 is cranked.

  Thus, the starter 15 operates by energizing the solenoid 23 as an electric load (that is, cranks the engine 13). On the other hand, if the solenoid 23 is not energized, the pinion gear 19 returns to the initial position where it does not mesh with the ring gear 14 (position shown in FIG. 1) by the force of a biasing member (not shown) such as a spring provided in the starter 15. The switch 21 is also turned off.

  Further, in the vehicle, two relays 27 and 28 are provided outside the ECU 11 to turn on and apply the battery voltage VB to the upstream side of the solenoid 23 to flow current to the solenoid 23.

Further, in the vehicle, an ignition key switch (hereinafter referred to as a key switch) 31 and an inhibitor switch 33 are provided outside the ECU 11.
The key switch 31 is provided in the ignition key cylinder of the driver's seat, and includes an accessory power supply terminal 35 (ACC), an ignition power supply terminal 36 (IG), and a start signal terminal 37 (STA).

  When the vehicle key inserted in the ignition key cylinder is twisted to the accessory position, the key switch 31 connects the positive terminal of the battery 20 to the accessory power terminal 35, and the key twists to the ignition position. When operated, the plus terminal of the battery 20 is connected to the accessory power terminal 35 and the ignition power terminal 36, and when the key is twisted to the start position, the plus terminal of the battery 20 is started with the ignition power terminal 36. Connect to the signal terminal 37.

The inhibitor switch 33 is turned on when the shift position of the automatic transmission is the parking lock or the neutral.
The start signal terminal 37 of the key switch 31 is connected to one end (upstream side) of the coil 27 a of the relay 27, and the other end (downstream side) of the coil 27 a is connected to the ground line via the inhibitor switch 33. To be connected to.

  For this reason, when the driver of the vehicle performs a start operation of twisting the key inserted in the ignition key cylinder to the start position in a state where the shift position of the automatic transmission is set to the parking lock or neutral, the key switch 31 Then, a current flows through the coil 27a of the relay 27 through the inhibitor switch 33, the relay 27 is turned on (specifically, the contact of the relay 27 is short-circuited), and the energization path from the battery 20 to the solenoid 23 is communicated. The starter 15 operates.

  When the engine 13 is cranked by the starter 15, another electronic control unit (hereinafter referred to as an engine ECU) that controls the engine 13 detects the rotation of the crankshaft of the engine 13 and injects fuel into the engine 13. As a result, the engine 13 is in a complete explosion state (an operation state in which the start is completed, a state in which the so-called engine 13 is applied). Thus, the case where the engine 13 is started according to a driver | operator's starting operation is a user starting time. If the engine 13 is a diesel engine, ignition is not performed and only fuel injection is performed. Further, the ECU 11 may also control the engine 13.

  On the other hand, the battery voltage VB is supplied to one end of the coil 28a of the relay 28, and the downstream side which is the other end of the coil 28a is grounded by the ECU 11 (that is, connected to the ground line). Yes.

  Therefore, when the downstream side of the coil 28a is grounded by the ECU 11 and a current flows through the coil 28a, the relay 28 is turned on (specifically, the contact of the relay 28 is short-circuited), and the energization path from the battery 20 to the solenoid 23 is established. The starter 15 operates in communication.

  The battery voltage VB is supplied to the terminal 40 of the ECU 11 from the ignition power supply terminal 36 of the key switch 31. In the following description, when the battery voltage VB supplied from the ignition power supply terminal 36 to the terminal 40 of the ECU 11 is distinguished from the voltage of the plus terminal of the battery 20, “Vb” is used as a sign of the battery voltage. .

  The battery voltage Vb from the ignition power supply terminal 36 is a battery voltage as an ignition power supply in the vehicle (in other words, an ignition system battery voltage), and the ECU 11 supplies the battery voltage Vb to the terminal 40 as an external power supply voltage. By doing so, it is designed to operate.

  Although not shown, the ECU 11 provides the ECU 11 with an information signal for automatically stopping and starting the engine 13, for example, a brake signal from a sensor that detects that the brake pedal has been depressed, an accelerator pedal, Accelerator signal from the sensor that detects that the vehicle has been stepped on, vehicle speed signal from the sensor that detects the vehicle traveling speed (vehicle speed), rotation signal from the crankshaft sensor and camshaft sensor, signal from the brake negative pressure sensor, etc. Is entered.

Next, the configuration of the ECU 11 will be described.
The ECU 11 includes a microcomputer 41 that executes various processes, an input circuit 43 that inputs the information signal to the microcomputer 41, a terminal 45 that is connected to the downstream side of the coil 28a of the relay 28, and an upstream side of the coil 27a of the relay 27. A terminal 47 connected to the relay 27, a terminal 49 connected downstream of the coil 27a of the relay 27, a transistor T1 having two output terminals connected between the terminal 45 and the ground line, and a battery in the ECU 11. The transistor T2 has two output terminals connected between the voltage Vb line and the terminal 47, and the transistor T3 has two output terminals connected between the terminal 49 and the ground line.

  In the present embodiment, the transistors T1 and T3 are, for example, N-channel MOSFETs, and the transistor T2 is, for example, a P-channel MOSFET. The transistor T1 has its drain and source connected between the terminal 45 and the ground line. Similarly, the transistor T3 has its drain and source between the terminal 49 and the ground line. It is connected. In addition, the source and drain of the transistor T2 are connected between the line of the battery voltage Vb and the terminal 47.

  A control signal SD1 from the microcomputer 41 is input to the gate of the transistor T1, and similarly, a control signal SD3 from the microcomputer 41 is input to the gate of the transistor T3. In addition, the ECU 11 is provided with a drive circuit 51 that turns on and off the transistor T2 by switching the gate voltage of the transistor T2 between 0 V and the battery voltage Vb in accordance with a control signal SD2 from the microcomputer 41.

Furthermore, the ECU 11 includes a monitor circuit 53 for detecting an abnormality.
The monitor circuit 53 includes a pull-down resistor 54 connected between the drain and terminal 45 of the transistor T1 and the ground line, and a comparison in which an inverting input terminal (− terminal) is connected to the drain and terminal 45 of the transistor T1. The battery voltage Vb from the comparator 55 and the terminal 40 is divided, and the divided voltage (in this embodiment, for example, a voltage obtained by halving the battery voltage Vb) is supplied to the non-inverting input terminal (+ terminal) of the comparator 55. ) Are input as threshold voltages, and a pull-up resistor connected between a line of a constant internal power supply voltage VD (for example, 5 V in this embodiment) and the output terminal of the comparator 55. 58.

  Then, the output of the comparator 55 is input to the microcomputer 41 as the monitor signal SM. Further, the resistance value of the resistor 54 is set to a value sufficiently larger than the resistance value of the coil 28a (for example, 1000 times or more).

  The internal power supply voltage VD is generated in the ECU 11 by stepping down the battery voltage Vb from the terminal 40 by the power supply circuit 60. The internal power supply voltage VD is a power supply voltage for operating the microcomputer 41.

  Although not shown in FIG. 1, in the ECU 11, the battery voltage Vb is divided by the two resistors to be equal to or lower than the internal power supply voltage VD, and the divided voltage is input to the microcomputer 41. It has become. The microcomputer 41 detects the value of the battery voltage Vb (and hence the value of the battery VB) by AD converting the divided voltage with an internal AD converter.

  In the ECU 11 having the above hardware, when the microcomputer 41 sets the control signal SD1 to the active level (high in the present embodiment) to turn on the transistor T1, a current (drive current) flows through the coil 28a of the relay 28. As a result, the relay 28 is turned on. As a result, the solenoid 23 is energized and the starter 15 operates. Regardless of the state of the key switch 31 and the inhibitor switch 33, if the microcomputer 41 sets both the control signal SD2 and the control signal SD3 to the active level (high in this embodiment) and turns on the transistor T2 and the transistor T3. A current flows through the coil 27a of the relay 27 and the relay 27 is turned on. As a result, the solenoid 23 is energized and the starter 15 operates.

  That is, the ECU 11 can operate the starter 15 by turning on the relay 28 different from the relay 27 that is turned on at the time of user start, and can further operate the starter 15 by forcibly turning on the relay 27. You can also.

  On the other hand, in the ECU 11, when the transistor T1 is off, the voltage at the inverting input terminal of the comparator 55 becomes the battery voltage VB higher than the threshold voltage (Vb / 2). The monitor signal SM to 41 becomes low (0 V).

  On the other hand, when the transistor T1 is turned on or even when the transistor T1 is turned off, the terminal 45 (specifically, the drain of the transistor T1 is connected from the battery voltage VB line via the coil 28a of the relay 28). In the case where the drive current path (including the coil 28a itself) for turning on the relay 28 is disconnected, the inverting input of the comparator 55 is reached. Since the terminal voltage is smaller than the threshold voltage, the monitor signal SM becomes high (internal power supply voltage VD).

  In the present embodiment, the energization wiring connected to the upstream side of the solenoid 23 branches at the branch point 61 to the relay 27 side and the relay 28 side. The wiring 62 extending from the battery voltage VB line to the contact of the relay 27, the wiring 63 extending from the contact of the relay 27 to the branch point 61, and the relay 27 itself are used to energize the solenoid 23 at the time of user start. An energization circuit (hereinafter referred to as a user start circuit) 64 is provided. When the wiring 65 extending from the battery voltage VB line to the contact of the relay 28, the wiring 66 extending from the contact of the relay 28 to the branch point 61, and the relay 28 itself automatically start the engine 13 (hereinafter referred to as the following). , Which is also referred to as “automatic start”), is an energization circuit for energizing the solenoid 23 (that is, an energization circuit in parallel with the user start circuit 64, hereinafter referred to as an “automatic start circuit”) 67.

Next, the contents of the process performed by the microcomputer 41 will be described.
The microcomputer 41 executes the automatic stop control process shown in FIG. 2 at regular intervals, for example, during operation of the engine 13 (when it is in an operating state).

  As shown in FIG. 2, when starting the automatic stop control process, the microcomputer 41 determines whether or not a predetermined automatic stop condition is satisfied in S102, and determines that the automatic stop condition is not satisfied. However, if the automatic stop condition is determined to be satisfied, the process proceeds to S104.

  An example of the automatic stop condition is that, for example, all the following conditions are satisfied. The vehicle speed is below a predetermined value. The brake pedal is depressed. The accelerator pedal is not depressed. Battery voltage VB is greater than or equal to a predetermined value. The absolute value of the brake negative pressure is greater than or equal to a predetermined value.

  In S104, the microcomputer 41 gives an engine stop command to the engine ECU to stop the fuel injection to the engine 13 or to shut off the intake air supply path to the engine 13 to automatically start the engine 13. Then, the automatic stop control process is terminated. The state in which the engine 13 is automatically stopped in this way is during idle stop.

Further, the microcomputer 41 executes the automatic start control process shown in FIG. 3 at regular intervals, for example, during idle stop.
As shown in FIG. 3, when starting the automatic start control process, the microcomputer 41 first determines in S110 whether or not an automatic start condition for automatically starting the engine 13 is satisfied, and the automatic start condition is determined. If it is determined that the automatic start condition is not satisfied, the automatic start control process is terminated, but if it is determined that the automatic start condition is satisfied, the process proceeds to S120.

  An example of the automatic start condition is one of the following conditions. The brake pedal was released. The accelerator pedal was depressed. The battery voltage VB has become below a predetermined value. The absolute value of the brake negative pressure has fallen below the predetermined value.

  In S120, the microcomputer 41 determines whether or not the monitor signal SM from the comparator 55 is low. At this point, since the microcomputer 41 has the control signal SD1 low, if normal, the transistor T1 is off and the monitor signal SM is low.

  If it is determined in S120 that the monitor signal SM is low, no disconnection has occurred in the drive current path of the relay 28 described above, and the relay 28 can be turned on (ie, automatic). It is determined that the starting circuit 67 functions normally), and the process proceeds to S130.

  In S130, the microcomputer 41 sets the control signal SD1 to high to turn on the transistor T1 in order to operate the starter 15. That is, the automatic start circuit 67 is energized to the solenoid 23 of the starter 15.

  Then, in the next S140, it is determined whether or not the engine 13 has been started. Specifically, it is determined whether or not the engine 13 is in a complete explosion state based on the engine speed calculated from the aforementioned rotation signal.

  If it is determined in S140 that the engine 13 has not been started, the process proceeds to S150, where it is determined whether or not the elapsed time since the control signal SD1 is set high in S130 exceeds a predetermined time. If the elapsed time does not exceed the predetermined time, the process returns to S140.

  If it is determined in S140 that the engine 13 has been started, the process proceeds to S160 where the control signal SD1 is set to low to turn off the transistor T1. Then, the automatic start control process ends.

  On the other hand, if it is determined in S120 that the monitor signal SM is not low (high), the process proceeds to S180 without performing the process of S130. That is, if the monitor signal SM is high, it is determined that a disconnection has occurred in the drive current path of the relay 28 and the relay 28 cannot be turned on (that is, the automatic start circuit 67 does not function normally). Thus, the process proceeds to S180 without setting the control signal SD1 to high.

  If it is determined in S150 that the elapsed time has exceeded the predetermined time, the engine 13 cannot be started within the predetermined time after the automatic start circuit 67 is energized to the solenoid 23. Therefore, it is determined that the automatic start circuit 67 does not function normally, and the process proceeds to S170. In S170, the control signal SD1 is set to low to turn off the transistor T1, and then the process proceeds to S180. In other words, in this case, although the automatic start circuit 67 is determined to be normal in S120, the automatic start circuit 67 actually does not function normally. For example, among the abnormalities of the automatic starting circuit 67, when the relay 28 is turned off (failed not to be turned on even when the coil 28a is energized) or the wiring 65 or the wiring 66 is disconnected, the above S150 is started. The process proceeds to S170 and proceeds to S180.

  In S180, a warning process is performed to warn the driver that an abnormality has occurred in the automatic start circuit 67. As the warning process, a process of turning on a warning lamp that is visible from the driver's seat or displaying a message on the display device can be considered.

  In step S190, the control signal SD2 is set high to turn on the transistor T2, and in step S200, the control signal SD3 is set high to turn on the transistor T3. That is, not the automatic start circuit 67 but the user start circuit 64 is energized to the solenoid 23 to operate the starter 15.

Next, in S210, it is determined whether the start of the engine 13 has been completed as in S140.
If it is determined in S210 that the start of the engine 13 has not been completed, the process proceeds to S220, and the elapsed time since the control signal SD3 was made high in S200 (that is, the user start circuit 64 is connected to the solenoid 23). It is determined whether or not (elapsed time since the energization is performed) exceeds a predetermined time. If the elapsed time does not exceed the predetermined time, the process returns to S210.

  If it is determined in S210 that the start of the engine 13 has been completed, the process proceeds to S230 where the control signal SD2 is set to low to turn off the transistor T2, and in S240, the control signal SD3 is set to low to set the transistor. Turn off T3. Then, the automatic start control process ends.

  On the other hand, if it is determined in S220 that the elapsed time has exceeded the predetermined time, the engine 13 cannot be started within the predetermined time after the user starting circuit 64 is energized to the solenoid 23. Therefore, it is determined that the user starting circuit 64 does not function normally, and the process proceeds to S250. In such a case, it is considered extremely rare.

In S250, the control signal SD2 is set to low to turn off the transistor T2. In S260, the control signal SD3 is set to low to turn off the transistor T3.
Further, in the next S270, a warning process for warning the driver that an abnormality has occurred in the user start circuit 64 is performed, and then the automatic start control process is terminated. Note that the warning process in S270 may be a process of turning on a warning lamp or displaying a message on a display device.

Next, the operation of the ECU 11 as described above will be described.
First, if the automatic start circuit 67 is normal when the automatic start condition is established during idle stop, the monitor signal SM becomes low as shown in FIG. "YES" is determined. For this reason, the transistor T1 is turned on by the process of S130 of FIG. 3, and as a result, the solenoid 23 is energized by the automatic start circuit 67 and the starter 15 operates. When the start of the engine 13 is completed (S140 in FIG. 3: YES), the transistor T1 is turned off (S160 in FIG. 3).

Thus, if the automatic start circuit 67 is normal, the starter 15 is driven by the automatic start circuit 67 and the engine 13 is started.
Next, if the drive current path for turning on the relay 28 is disconnected when the automatic start condition is established during the idle stop, the monitor signal SM becomes high as shown in FIG. Therefore, it is determined as “NO” in S120 of FIG. For this reason, the transistors T2 and T3 are turned on by the processing of S190 and S200 in FIG. 3, and as a result, the solenoid 23 is energized by the user starting circuit 64 and the starter 15 operates. When the start of the engine 13 is completed (S210 in FIG. 3: YES), the transistors T2 and T3 are turned off (S230 and S240 in FIG. 3).

Thus, if the automatic start circuit 67 is not normal, the starter 15 is driven by the user start circuit 64 and the engine 13 is started.
On the other hand, when the automatic start condition is established during the idle stop, the drive current path of the relay 28 is not disconnected, but the relay 28 is off or the wiring 65 or the wiring 66 is disconnected. As shown in FIG. 6, the monitor signal SM becomes low as in the normal state shown in FIG. 4, and therefore “YES” is determined in S <b> 120 of FIG. 3.

  Therefore, the transistor T1 is turned on by the process of S130 in FIG. 3, but the automatic start circuit 67 does not function (that is, the solenoid 23 cannot be energized), so the starter 15 does not operate and the engine 13 Does not start.

  Therefore, when a predetermined time has elapsed after the processing of S130 of FIG. 3 is performed, “YES” is determined in S150 of FIG. 3, and thereafter, S190 and S200 of FIG. 3 are performed as in the case shown in FIG. As a result, the transistors T2 and T3 are turned on. As a result, the user start circuit 64 energizes the solenoid 23 and the starter 15 operates. When the start of the engine 13 is completed (S210 in FIG. 3: YES), the transistors T2 and T3 are turned off (S230 and S240 in FIG. 3).

  As described above, when the ECU 11 determines that the automatic start circuit 67 does not function normally when the automatic start condition is satisfied and the engine 13 is automatically started, the ECU 11 is connected to the user start circuit 64. The engine 13 is automatically started by operating the starter 15 by energizing.

  For this reason, for example, even when an abnormality occurs in the automatic start circuit 67 after the engine 13 is automatically stopped, and when the automatic start condition is satisfied, the automatic start circuit 67 is abnormal, The engine 13 can be automatically started by operating the starter 15 using the user starting circuit 64. Therefore, it is possible to prevent the automatic start of the engine 13 from being disabled.

  In particular, among automatic start conditions, for example, a condition that the battery voltage VB has become a predetermined value or less, a condition that the absolute value of the brake negative pressure has become a predetermined value or less, and other conditions other than the driver's action are established. Even in this case, the engine 13 can be automatically started without making the driver aware of it.

  Further, when the automatic start condition is satisfied, the ECU 11 causes the automatic start circuit 67 to energize the solenoid 23 (S130), and whether or not the engine 13 can be started within a predetermined time from that point. If the engine 13 cannot be started within a predetermined time (S150: YES), it is determined that the automatic start circuit 67 does not function normally, and the user start circuit 64 is configured to energize the solenoid 23 (S190, S200).

  Therefore, even if an abnormality that cannot be detected by the determination of S120 in FIG. 3 among the abnormality of the automatic start circuit 67 occurs, the engine 13 can be automatically started. Since it is difficult to reliably detect all types of abnormalities (failure modes) in the automatic start circuit 67, it is very effective to have such a configuration.

  Furthermore, the ECU 11 determines whether or not the automatic start circuit 67 functions normally based on the determination in S120 of FIG. 3 before energizing the solenoid 23 in the automatic start circuit 67. If it is determined in S120 that the automatic start circuit 67 functions normally (S120: YES), the automatic start circuit 67 is energized to the solenoid 23 (S130). If it is determined that the circuit 67 does not function properly (S120: NO), the user start circuit 64 is energized to the solenoid 23 without causing the automatic start circuit 67 to energize the solenoid 23. (S190, S200).

  Therefore, when the automatic start condition is satisfied, if an abnormality that can be detected by the determination of S120 in FIG. 3 among the abnormalities of the automatic start circuit 67 occurs, the user start circuit 64 immediately The starter 15 can be operated. Specifically, the starter 15 can be operated without waiting for a predetermined time to elapse, and as a result, the time from when the automatic start condition is satisfied until the start of the engine 13 is completed can be shortened. it can.

  In the first embodiment, the current that flows through the coil 28a of the relay 28 by turning on the transistor T1 (the drive current of the relay 28) corresponds to an example of a drive signal applied to the second energization means.

[Second Embodiment]
Next, the second embodiment will be described. Since the same or similar components as those in the first embodiment are denoted by the same reference numerals as those used in the first embodiment, detailed description thereof will be omitted. This also applies to other embodiments described later.

As shown in FIG. 7, the ECU 69 of the second embodiment is different from the ECU 11 of the first embodiment in the following (1-1) to (1-5) in terms of hardware.
(1-1) Outside the ECU 69, the upstream side of the coil 27a of the relay 27 is connected to the line of the battery voltage VB. The downstream side of the coil 27 a is connected to the terminal 49 of the ECU 69 without being connected to the inhibitor switch 33.

(1-2) Outside the ECU 69, the start signal terminal 37 of the key switch 31 is connected to the terminal 70 of the ECU 69 via the inhibitor switch 33.
For this reason, when the driver of the vehicle performs the aforementioned start operation in the state where the shift position of the automatic transmission is set to the parking lock or neutral, the battery voltage VB is transferred from the start signal terminal 37 of the key switch 31 to the inhibitor switch. Then, the data is input to the terminal 70 of the ECU 69 through 33. The battery voltage VB input to the terminal 70 is the user start signal SUS.

  (1-3) The ECU 69 has a pull-down resistor 71 connected between the terminal 70 and the ground line, a resistor 72 having one end connected to the terminal 70, and an anode connected to the other end of the resistor 72. And a diode 73. The cathode of the diode 73 is connected to the gate of the transistor T3. Therefore, the user start signal SUS input to the terminal 70 is input to the gate of the transistor T3 via the resistor 72 and the diode 73.

  (1-4) Further, the ECU 69 is provided with a diode 74, and the cathode of the diode is connected to the cathode of the diode 73 and the gate of the transistor T3. Then, the control signal SD3 from the microcomputer 41 is input to the anode of the diode 74.

(1-5) The ECU 69 does not have the transistor T2, the drive circuit 51, and the terminal 47.
Due to the above differences, in the ECU 69 of the second embodiment, when the driver of the vehicle performs the above-described start operation in a state where the shift position of the automatic transmission is set to the parking lock or neutral, the user from the terminal 70 The start signal SUS is supplied to the gate of the transistor T3, and the transistor T3 is turned on. Then, a current flows through the coil 27a of the relay 27, the relay 27 is turned on, and the starter 15 is operated.

  Regardless of the state of the key switch 31 and the inhibitor switch 33, if the microcomputer 41 sets the control signal SD3 to high, the transistor T3 is turned on, the relay 27 is turned on, and the starter 15 is operated.

  That is, the microcomputer 41 of the ECU 69 can forcibly turn on the relay 27 by turning on one transistor T3 (that is, the user starting circuit 64 can energize the solenoid 23).

Therefore, the microcomputer 41 of the ECU 69 executes the automatic start control process of FIG. 8 instead of the automatic start control process of FIG.
The automatic start control process of FIG. 8 is the same as the automatic start control process of FIG. 3 except that S190, S230, and S250 for turning on and off the transistor T2 are deleted.

  Even with the ECU 69 as described above, the same effect as that of the ECU 11 of the first embodiment can be obtained, and the transistor T2 can be eliminated. Also, the transistor T3 is originally a transistor for turning on the relay 27 at the time of user start, and therefore it is not necessary to add the transistor T3.

[Third Embodiment]
As shown in FIG. 9, the ECU 75 of the third embodiment differs from the ECU 69 of the second embodiment in the following (2-1) to (2-3) in terms of hardware.

(2-1) A starter 76 instead of the starter 15 is mounted on a vehicle provided with the ECU 75 of the third embodiment.
The starter 76 is an independently controlled starter that can independently move the pinion gear 19 to the meshing position with the ring gear 14 and operate the motor 17 (energization of the motor 17).

More specifically, the starter 76 includes a solenoid 25 in addition to the motor 17, the pinion gear 19, the switch 21, and the solenoid 23 similar to the starter 15.
One end of the solenoid 25 is connected to the ground line. When the battery voltage VB is applied to the upstream side which is the other end of the solenoid 25 and the solenoid 25 is energized, the switch 21 is turned on by the electromagnetic force of the solenoid 25 and the energization from the battery 20 to the motor 17 is performed. The path communicates and the motor 17 operates.

  Also in the starter 76, as with the starter 15, when the battery voltage VB is applied to the upstream side of the solenoid 23 and the solenoid 23 is energized, the pinion gear 19 protrudes to the meshing position by the electromagnetic force of the solenoid 23. To do.

  Thus, the solenoid 23 is a pinion control solenoid for meshing the pinion gear 19 with the ring gear 14, and the solenoid 25 is a motor control solenoid for operating the motor 17 by turning on the switch 21. The starter 76 operates by energizing both the solenoid 23 and the solenoid 25 (that is, cranks the engine 13).

  (2-2) In the vehicle, two relays 29 and 30 are provided outside the ECU 75 so as to apply the battery voltage VB to the upstream side of the solenoid 25 and flow current to the solenoid 25 by being turned on.

  The battery voltage VB is supplied to one end of the coil 29a of the relay 29, and the downstream side which is the other end of the coil 29a is grounded by the ECU 75. Therefore, when the downstream side of the coil 29a is grounded by the ECU 75 and a current flows through the coil 29a, the relay 29 is turned on (the contact of the relay 29 is short-circuited), and the energization path from the battery 20 to the solenoid 25 is communicated. The motor 17 operates.

  Similarly, the battery voltage VB is also supplied to one end of the coil 30a of the relay 30, and the downstream side which is the other end of the coil 30a is grounded by the ECU 75. For this reason, when the downstream side of the coil 30a is grounded by the ECU 75 and current flows through the coil 30a, the relay 30 is turned on (the contact of the relay 30 is short-circuited), and the energization path from the battery 20 to the solenoid 25 is communicated. The motor 17 operates.

  Here, in the third embodiment, the energization wiring connected to the upstream side of the solenoid 25 branches at the branch point 77 to the relay 29 side and the relay 30 side. The wiring 78 from the battery voltage VB line to the contact point of the relay 29, the wiring 79 from the contact point of the relay 29 to the branch point 77, and the relay 29 itself are used to energize the solenoid 25 when the user starts. This is a user start circuit 80 which is an energization circuit. Further, the wiring 81 from the battery voltage VB line to the contact of the relay 30, the wiring 82 from the contact of the relay 30 to the branch point 77, and the relay 30 itself are used to energize the solenoid 25 at the time of automatic start. It is an automatic start circuit 83 which is an energization circuit.

Also in the third embodiment, the battery voltage VB is applied to the upstream side of the solenoid 23 by one of the two relays 27 and 28.
That is, in the third embodiment, when starting the user, the user starting circuit 64 including the relay 27 is energized to the solenoid 23 and the user starting circuit 80 including the relay 29 is energized to the solenoid 25. As a result, the starter 76 is operated. Further, at the time of automatic start, the starter 76 is energized by causing the automatic start circuit 67 including the relay 28 to energize the solenoid 23 and causing the automatic start circuit 83 including the relay 30 to energize the solenoid 25. It will be operated.

  (2-3) In addition to the components provided in the ECU 69 of the second embodiment, the ECU 75 includes a terminal 84 connected to the downstream side of the coil 30a of the relay 30 and a downstream side of the coil 29a of the relay 29. A connected terminal 85, a transistor T1m having two output terminals connected between the terminal 84 and the ground line, a transistor T3m having two output terminals connected between the terminal 85 and the ground line, and a diode 86, a delay circuit 87, and an abnormality detection monitor circuit 88.

  In the present embodiment, the transistors T1m and T3m are MOSFETs. The drain and source of the transistor T1m are connected between the terminal 84 and the ground line. Similarly, the drain and source of the transistor T3m are connected between the terminal 85 and the ground line.

  Therefore, when the transistor T1m is turned on, a current flows through the coil 30a of the relay 30 to turn on the relay 30, and the solenoid 25 is energized to operate the motor 17. When the transistor T3m is turned on, a current flows through the coil 29a of the relay 29, the relay 29 is turned on, the solenoid 25 is energized, and the motor 17 operates.

  Further, a control signal SD1m from the microcomputer 41 is input to the gate of the transistor T1m. Further, the control signal SD3m from the microcomputer 41 is inputted to the gate of the transistor T3m via the diode 86.

  In the third embodiment, among the same components as in the ECU 69 of the second embodiment, “T1p” is used as a symbol corresponding to the transistor T1, and “T3p” is used as a transistor corresponding to the transistor T3. Used. Furthermore, “SD1p” is used as the sign of the control signal output from the microcomputer 41 to turn on the transistor T1p, and “SD3p” is used as the sign of the control signal output from the microcomputer 41 to turn on the transistor T3p. “SMp” is used as the sign of the monitor signal output from the comparator 55 of the monitor circuit 53 to the microcomputer 41.

  On the other hand, the user start signal SUS input to the terminal 70 of the ECU 75 is input to the delay circuit 87 via the resistor 72. Then, the delay circuit 87 delays the input user start signal SUS by a predetermined delay time td and outputs it to the signal wiring between the cathode of the diode 86 and the gate of the transistor T3m. For example, the delay circuit 87 is mainly composed of an integrating circuit composed of a resistor and a capacitor. However, when the input signal (user start signal SUS) falls to 0V, the output signal immediately becomes 0V. It is comprised so that it may become.

  Therefore, in the ECU 75, when the user start signal SUS is input to the terminal 70 at the time of user start, first, the transistor T3p is turned on and the relay 27 is turned on, whereby the pinion gear 19 of the starter 76 and the ring gear 14 are turned on. Move to the meshing position. When the delay time td by the delay circuit 87 elapses after the user start signal SUS is input to the terminal 70, the transistor T3m is turned on and the relay 29 is turned on, so that the motor 17 of the starter 76 operates. Then, the starter 76 operates from that time, and the engine 13 is cranked by the starter 76. The reason why the motor 17 is operated after the pinion gear 19 is engaged with the ring gear 14 is to suppress wear of the pinion gear 19 and the ring gear 14.

  The monitor circuit 88 is the same circuit as the monitor circuit 53. That is, the monitor circuit 88 includes a pull-down resistor 89 connected between the drain and terminal 84 of the transistor T1m and the ground line, and a comparator 90 having an inverting input terminal connected to the drain and terminal 84 of the transistor T1m. The battery voltage Vb from the terminal 40 is divided, and the divided voltage (in this embodiment, for example, a voltage obtained by halving the battery voltage Vb) is input to the non-inverting input terminal of the comparator 90 as a threshold voltage. Two resistors 91 and 92 and a pull-up resistor 93 connected between the line of the internal power supply voltage VD and the output terminal of the comparator 90 are provided.

  The output of the comparator 90 is input to the microcomputer 41 as the monitor signal SMm. In addition, the resistance value of the resistor 89 is set to a value sufficiently larger than the resistance value of the coil 30a (for example, 1000 times or more), like the resistor 54.

  In such a monitor circuit 88, when the transistor T1m is off, the voltage of the inverting input terminal of the comparator 90 is the battery voltage VB that is larger than the threshold voltage (Vb / 2) to the non-inverting input terminal. Therefore, the monitor signal SMm from the comparator 90 to the microcomputer 41 becomes low (0 V). Further, when the transistor T1m is turned on, or even when the transistor T1m is turned off, the terminal 84 (specifically, the drain of the transistor T1m and the resistor 89 are connected from the battery voltage VB line via the coil 30a of the relay 30). And the driving current path (including the coil 30a itself) for turning on the relay 30 is disconnected, the voltage at the inverting input terminal of the comparator 90 is Becomes smaller than the threshold voltage, the monitor signal SMm becomes high (internal power supply voltage VD).

  In the ECU 75 having the above hardware, when the microcomputer 41 sets the control signal SD1p and the control signal SD1m to high, the transistor T1p and the transistor T1m are turned on, the relay 28 and the relay 30 are turned on, and the solenoid 23 and the solenoid 25 are turned on. And the starter 76 operates. Regardless of the state of the key switch 31 and the inhibitor switch 33, when the microcomputer 41 sets the control signal SD3p and the control signal SD3m to high, the transistor T3p and the transistor T3m are turned on, the relay 27 and the relay 29 are turned on, and the solenoid 23 and solenoid 25 are energized and starter 76 operates.

  That is, the ECU 75 can operate the starter 76 by turning on the relays 28 and 30 that are different from the relays 27 and 29 that are turned on at the time of starting the user, and forcibly turn on the relays 27 and 29. The starter 76 can also be operated.

Therefore, as compared with the second embodiment, the microcomputer 41 of the ECU 75 executes the automatic start control process of FIG. 10 instead of the automatic start control process of FIG.
10 is different from the automatic start control process of FIG. 8 in the following points (3-1) to (3-8).

(3-1) S125 is provided instead of S120, and S133, S135, and S137 are provided instead of S130.
In S125, it is determined whether or not both the monitor signal SMp from the comparator 55 and the monitor signal SMm from the comparator 90 are low. At this time, since the microcomputer 41 sets the control signals SD1p and SD1m to low, the monitor signals SMp and SMm are set to low when normal.

  If it is determined in S125 that the monitor signals SMp and SMm are both low, there is no disconnection between the drive current path of the relay 28 and the drive current path of the relay 30, and the relay 28 It is determined that the relay 30 can be turned on (that is, the automatic start circuit 67 and the automatic start circuit 83 function normally), and the process proceeds to S133.

  In S133, the control signal SD1p is set high to turn on the transistor T1p, thereby causing the automatic start circuit 67 to energize the solenoid 23. In the next S135, the circuit waits for the same delay time td as the delay time td by the delay circuit 87. In the next S137, the control signal SD1m is set high to turn on the transistor T1m, thereby causing the automatic start circuit 83 to Energization of the solenoid 25 is performed. Then, if it is normal, cranking of the engine 13 by the starter 76 is started, the process proceeds to S140, and it is determined whether or not the start of the engine 13 is completed. That is, in S133 to S137, the motor 17 is operated after the pinion gear 19 is engaged with the ring gear 14 in the same manner as when the user is started.

  On the other hand, if it is determined in S125 that at least one of the monitor signals SMp and SMm is not low (high), either of the relays 28 and 30 cannot be turned on (that is, an automatic start circuit). 67 or 83 does not function normally), and the control signals SD1p and SD1m do not go high, and the flow proceeds to S180.

(3-2) S163 and S165 are provided instead of S160.
That is, if it is determined in S140 that the engine 13 has been started, the process proceeds to S163, the control signal SD1m is turned low to turn off the transistor T1m, and in the next S165, the control signal SD1p is turned low. The transistor T1p is turned off. Then, the automatic start control process ends.

(3-3) In S150, it is determined whether or not the elapsed time since the control signal SD1m was set high in S137 has exceeded a predetermined time.
(3-4) S173 and S175 are provided instead of S170.

  That is, when it is determined in S150 that the elapsed time has exceeded the predetermined time, the engine 13 can be started within a predetermined time after the energization of the solenoids 23 and 25 is performed in the automatic start circuits 67 and 83. Since this is not possible, it is determined that any of the automatic start circuits 67 and 83 does not function normally, and the process proceeds to S173.

  In step S173, the control signal SD1m is set to low. In step S165, the control signal SD1p is set to low. Then, the process proceeds to step S180. In this case, although it is determined in S125 that the automatic start circuits 67 and 83 are normal, in actuality, any of the automatic start circuits 67 and 83 does not function normally.

(3-5) S203, S205, and S207 are provided instead of S200.
In S203, the control signal SD3p is set to high to turn on the transistor T3p. In next S205, the control circuit waits for the same delay time td as the delay time td by the delay circuit 87. In next S207, the control signal SD3m is set to high. The transistor T3m is turned on.

  That is, in S203 to S207, not the automatic start circuits 67 and 83 but the user start circuits 64 and 80 are energized to the solenoids 23 and 25 to operate the starter 76. Also in this case, the motor 17 is operated after the pinion gear 19 is engaged with the ring gear 14.

(3-6) S243 and S245 are provided instead of S240.
In other words, if it is determined in S210 that the start of the engine 13 is completed, the process proceeds to S243, the control signal SD3m is turned low, the transistor T3m is turned off, and the control signal SD3p is turned low in the next S245. The transistor T3p is turned off. Then, the automatic start control process ends.

(3-7) In S220, it is determined whether or not the elapsed time since the control signal SD3m was set high in S207 has exceeded a predetermined time.
(3-8) S263 and S265 are provided instead of S260.

  That is, if it is determined in S220 that the elapsed time has exceeded the predetermined time, the engine 13 can be started within the predetermined time after the user starting circuits 64 and 80 are energized to the solenoids 23 and 25. Since this is not possible, it is determined that none of the user starting circuits 64 and 80 function normally, and the process proceeds to S263.

In step S263, the control signal SD3m is set to low. In step S265, the control signal SD3p is set to low. Then, the process proceeds to step S270.
In the third embodiment as described above, since the starter 76 to be controlled is an independent control type starter, there are the solenoid 23 and the solenoid 25 as electric loads for operating the starter 76. A user starting circuit 64 and an automatic starting circuit 67 are provided for the solenoid 23, and a user starting circuit 80 and an automatic starting circuit 83 are provided for the solenoid 25. For this reason, the microcomputer 41 of the ECU 75 operates the starter 76 by energizing the solenoids 23 and 25 in the automatic start circuits 67 and 83 in S133 and S137 of FIG. In S207, the starter 76 is operated by energizing the solenoids 23 and 25 in the user starting circuits 64 and 80, respectively.

  And according to ECU75 of 3rd Embodiment as mentioned above, even if the starter 76 of a control object is an independent control type starter, the effect similar to ECU69 of 2nd Embodiment is acquired. In the ECU 75, the transistors T3p and T3m are originally transistors for turning on the relays 27 and 29 when the user starts up, and therefore need not be added.

  In the third embodiment, the current that flows through the coil 28a of the relay 28 by turning on the transistor T1p (the drive current of the relay 28) and the current that flows through the coil 30a of the relay 30 by turning on the transistor T1m (the current of the relay 30). Drive current) corresponds to an example of a drive signal applied to the second energization means.

  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 automatic stop control process of FIG. 2 may be performed by a device different from the ECUs 11, 69, 75 of the above embodiments.
In the first embodiment or the second embodiment, part or all of the user start circuit 64 and the automatic start circuit 67 may be configured in the ECUs 11 and 69. Similarly, in the third embodiment, part or all of the user starting circuits 64 and 80 and the automatic starting circuits 67 and 83 may be configured in the ECU 75. Further, instead of the relays 27, 28, 29, 30, a switching element made of a semiconductor may be used.

  11, 69, 75 ... ECU, 13 ... engine, 15, 76 ... starter, 23, 25 ... solenoid, 41 ... microcomputer, 64, 80 ... user start circuit, 67, 83 ... automatic start circuit

Claims (4)

A starter (15, 76) having an electric load (23, 25) for driving and operating by energizing the electric load to crank the engine to start the engine (13) of the vehicle When,
A first energization means (64, 80) for operating the starter by energizing the electric load when a driver of the vehicle performs a start operation for starting the engine;
Automatic stop means (41, S102, S104) for stopping the engine when a predetermined automatic stop condition is satisfied during operation of the engine;
A second energizing means (67, 83) which is provided separately from the first energizing means and operates the starter by energizing the electric load when a drive signal is given;
A starter control device (11, 69, 75) for controlling the starter used in the vehicle comprising
Condition determining means (41, S110) for determining whether or not an automatic start condition for automatically starting the engine is satisfied after the engine is stopped by the automatic stop means;
When it is determined by the condition determination means that the automatic start condition is satisfied, the drive signal is given to the second energization means to cause the second energization means to energize the electric load, Normal control means (41, S130, S133, S137) for operating the starter to start the engine;
An abnormality determining means (41, S120, S125, S140, S150) for determining whether or not the second energizing means functions normally when the condition determining means determines that the automatic start condition is satisfied; ,
If the abnormality determining means determines that the second energizing means does not function normally, the starter is operated to start the engine by causing the first energizing means to energize the electrical load. An abnormality control means (41, S190, S200, S203, S207);
A starter control device comprising: The starter control device according to claim 1,
The abnormality determination means (41, S140, S150)
The normal control means determines whether or not the engine can be started within a predetermined time after the second energization means has energized the electric load, and the engine is started within the predetermined time. Determining that the second energizing means does not function normally when the second energizing means is not functioning normally,
A starter control device. In the starter control device according to claim 1 or 2,
The abnormality determination means (41, S120)
Before the normal control means starts operation, it is determined whether the second energization means functions normally. If it is determined that the second energization means function normally, the normal control means is Operating, if it is determined that the second energization means does not function normally, operating the abnormal time control means without operating the normal control means;
A starter control device. The starter control device according to any one of claims 1 to 3,
There are a plurality of electric loads (23, 25), and the first energizing means (64, 80) and the second energizing means (67, 83) for each of the plurality of electric loads (23, 25). And
The normal control means (41, S133, S137) causes each of the second energization means (67, 83) corresponding to the plurality of electric loads to energize the electric load, thereby causing the starter to operate. Make it work,
The abnormal time control means (41, S203, S207) also causes the first energization means (64, 80) corresponding to each of the plurality of electric loads to energize the electric load, thereby enabling the starter. Make the work,
A starter control device.

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