JP7721426B2 - Vehicle control device - Google Patents

Description

This invention relates to a vehicle control device equipped with control means that stops a running engine when predetermined automatic engine stop conditions are met, and automatically restarts a stopped engine when predetermined engine restart conditions are met.

Conventionally, vehicle control devices with a so-called idling stop function stop a running engine when predetermined automatic engine stop conditions are met, and automatically restart a stopped engine when predetermined engine restart conditions are met. In such a case, if it is determined that an occupant has left the seat while the engine is automatically stopped, technology has been proposed that transitions the engine to a running state even before the engine restart conditions are met, thereby making the occupant aware that automatic engine stop control is being implemented (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2000-97067

The technology in Patent Document 1 cites examples of means for notifying occupants that automatic engine stop control is being implemented, such as switching the engine to an operating state as described above, as well as audio output and flashing of lighting devices. However, it is also possible to combine switching the engine to an operating state with an audio or other warning.

Furthermore, in the technology of Patent Document 1, actions such as unfastening a seatbelt or opening the driver's door are considered to be actions by an occupant leaving their seat. In such cases, there is a risk that an intrusive alarm will be output. For example, if a vehicle is stopped with the shift position in park and the engine is in an idle-stop state, and the driver forgets that the engine is in the idle-stop state and unfastens their seatbelt before turning off the ignition switch, an alarm will be output. When the shift position is parked, the vehicle will not move even if the engine is restarted, so simply restarting the engine is sufficient to notify the driver, and outputting an alarm could be considered intrusive.

One possible solution is to not output an alarm when the shift position is in parking, but to determine whether the shift position is in parking range based on the on/off state of a relay switch installed in the parking range. However, because chattering can occur with switches such as relay switches, it takes a certain amount of time to accurately determine the shift position, which could delay the issuance of an alarm when it is needed.

The present invention was made in consideration of the above-mentioned problems, and aims to provide technology that can output an alarm early when necessary, while preventing the issuance of an intrusive alarm when an occupant attempts to exit the vehicle while the engine is automatically stopped.

In order to achieve the above-mentioned object, the vehicle control device of the present invention is a vehicle control device equipped with a control means that stops a running engine when a predetermined engine automatic stop condition is met and automatically restarts a stopped engine when a predetermined engine restart condition is met, and is equipped with an alarm output means that can output an alarm to an occupant, and switches are provided individually for multiple shift ranges including a parking range, and the shift position can be detected based on the on/off state of each of the switches for the multiple shift ranges, and the control means is capable of determining whether a predetermined dismounting condition indicating that the occupant intends to dismount has been met, and The state of the switches for each range can be detected, and when the control means determines that the specified dismount condition has been met between the time when the specified engine automatic stop condition is met and the time when the specified engine restart condition is met, if the state of the switches for each of the multiple shift ranges detected by the control means is a first state in which the switch for the parking range is on and all of the switches for the other shift ranges are off, output from the alarm output means is prohibited, and if the state of the switches for each of the multiple shift ranges is other than the first state, an alarm is output from the alarm output means.

According to the present invention, if a predetermined disembarkation condition is met while the engine is automatically stopped, the output of an alarm is prohibited if the shift position is in the parking range. This prevents an intrusive alarm from being output when the vehicle is not moving even if the engine is restarted. Furthermore, whether the shift position is in the parking range is determined by detecting the state of all switches in each shift range. In this case, compared to a method that takes a predetermined amount of time to determine whether the shift position is in the parking range, in order to prevent erroneous determinations due to chattering of the switches in each range, a determination can be made earlier, and an alarm can be output earlier when necessary.

1 is a block diagram of an embodiment of a vehicle control device of the present invention; FIG. 2 is a diagram showing an example of a circuit diagram of the shift range switch of FIG. 1 . 2 is a flowchart illustrating the operation of FIG. 1 .

Next, to explain the present invention in more detail, an embodiment in which the present invention is applied to an idle-stop vehicle will be described with reference to Figures 1 to 3.

Figure 1 shows the block diagram of a vehicle control device provided in an idle-stop vehicle 1. In order to reduce weight and size, idle-stop vehicle 1 is equipped with a single, relatively small-capacity 12V lead battery 2 (hereinafter referred to as battery 2) as a power source. The negative terminal of battery 2 is connected to the body of idle-stop vehicle 1 and is grounded. Meanwhile, the positive terminal of battery 2 is connected to one end of relay switch 7b.

In Figure 1, 3 is the engine of the idle-stop vehicle 1, 4 is the CVT on the transmission side of the engine 3, and a torque converter (including a lock-up clutch mechanism) 5 is interposed between the engine 3 and the CVT.

Reference numeral 6 denotes a starter that starts the engine 3, and is supplied with power from the battery 2 via a relay 7. Reference numeral 9 denotes a generator with motor function (hereinafter referred to as an ISG (Integrated Starter Generator)) to which the rotational force of the engine 3 is transmitted via a belt 10. While driving, the generator output charges the battery 2, and under specified conditions it operates as a motor, generating driving force for the idle-stop vehicle 1.

The relay 7 has a relay coil 7a and a relay switch 7b. When current flows through the relay coil 7a, the relay switch 7b turns ON, power is supplied to the starter 6 from the battery 2, and the engine 3 starts. Furthermore, when current is no longer flowing through the relay coil 7a, the relay switch 7b turns OFF, and power supply to the starter 6 is stopped.

Reference numeral 11 denotes an EFI/CVT/IDS integrated ECU (Electronic Control Unit) that integrates an EFI control unit that calculates the required torque based on the accelerator opening detected by an accelerator sensor (not shown) and controls the fuel injection amount, intake air amount, ignition timing, etc. of the engine 3 to output this required torque, a CVT control unit that controls the CVT (continuously variable transmission), and an idling stop control unit that manages idling stop control.

The EFI/CVT/IDS integrated ECU 11 (corresponding to the "control means" of the present invention) is equipped with a first driver IC 11a connected to one end of the relay coil 7a and functioning as a switch to determine whether or not to connect that end to the battery 2, a second driver IC 11b connected to the other end of the relay coil 7a and functioning as a switch to determine whether or not to ground that other end, and a microcomputer (not shown) that controls these ICs 11a and 11b, and performs controls such as restarting the engine 3 after an idling stop, which will be described later.

In this embodiment, the EFI/CVT/IDS integrated ECU 11 is connected to a speaker 16 (corresponding to the "alarm output means" of the present invention) and controls the output of an alarm issued from the speaker 16 when a predetermined condition is met. Here, the predetermined condition is a condition for determining that an occupant has performed an action indicating an intention to exit the vehicle during idling stop control, and will be described in more detail below.

Reference numeral 12 denotes a body ECU that determines whether the doors of the idle stop vehicle 1 are open, whether the doors of the idle stop vehicle 1 are locked, and whether the seat belt is fastened. Connected to the body ECU 12 are a door open/close sensor 13 that detects the open/close state of each of the doors (front doors and rear doors) of the idle stop vehicle 1, and a seat belt fastening/unfastening sensor 14 that detects whether the seat belt is fastened or not.

Other ECUs not shown include an engine ECU that controls the engine, an ABS ECU that controls the ABS (antilocked braking system) that prevents skidding and spinning, and an ISG ECU that controls the ISG. Each ECU is formed by a microcomputer or similar device, and exchanges information via a communication bus (not shown) such as CAN15.

The shift range switch 8 is composed of multiple switches 8a-8f, each individually positioned to correspond to the position of the shift lever. Specifically, as shown in Figure 2, the shift range switch 8 is composed of a P-range switch 8a corresponding to the parking range, an R-range switch 8b corresponding to the reverse range, an N-range switch 8c corresponding to the neutral range, a D-range switch 8d corresponding to the drive range, an S-range switch 8e corresponding to the S-range, and a B-range switch 8f corresponding to the B-range.

Now, the connection configuration of the shift range switch circuit will be explained with reference to Figure 2. One end of the P-range SW8a is connected to port P1 (P) of the second driver IC 11b, and the other end is connected to ground GND1 via the common ground line 20. One end of the R-range SW8b is connected to port P2 (R) of the second driver IC 11b, and the other end is connected to a power supply. One end of the R-range SW8b is also connected to one end of the backup lamp 21. The other end of the backup lamp 21 is connected to ground GND2. Therefore, when the R-range SW8b is turned on, power is supplied, causing current to flow through the backup lamp 21, and the backup lamp 21 is illuminated. One end of the N-range SW8c is connected to port P3 (N) of the second driver IC 11b, and the other end is connected to ground GND1 via the common ground line 20. The D-range SW8d has one end connected to port P4 (D) of the second driver IC 11b and the other end connected to ground GND1 via a common ground line. The S-range SW8e has one end connected to port P5 (S) of the second driver IC 11b and the other end connected to ground GND1 via a common ground line 20. The B-range SW8f has one end connected to port P6 (B) of the second driver IC 11b and the other end connected to ground GND1 via a common ground line.

In this embodiment, each of range switches 8a through 8f is a relay switch that is configured to turn on when the shift lever is shifted to the corresponding position and to turn off when the shift lever is shifted to any other corresponding position.

Here, we will explain the general control and operation of the idle-stop vehicle 1. When the driver turns on the ignition (IG) key switch 18 to command engine start while the shift lever (not shown) is in P or N range, a signal from the IG key switch 18 is input, for example, via a communication bus, to the EFI/CVT/IDS integrated ECU 11. Based on this input, the EFI/IDS integrated ECU 11 momentarily energizes and turns on the relay 7, supplies power from the battery 2 to the starter 6, starts the starter 6, and starts the stopped engine 3 (initial start).

When the shift position is in P or N, the P range SW 8a or N range SW 8c shown in Figure 2 is in the ON state. In this case, the other end of the relay coil 7a is electrically connected to ground GND1. Therefore, the current to the relay coil 7a associated with initial startup flows from one end of the relay coil 7a to the other end, and then falls from the other end to ground GND1 via the P range SW 8a or N range SW 8c. This energization of the relay coil 7a closes the relay switch 7b, causing the engine 3 to start.

Once the engine 3 starts and the battery 2 is fully charged using power generated by the ISG (not shown), the EFI/CVT/IDS integrated ECU 11 then executes idle stop control until the IG key switch 18 is turned off and the engine 3 is stopped.

The EFI/CVT/IDS integrated ECU 11 receives, via the CAN 15, engine 3 information such as engine 3 RPM and coolant temperature, battery 2 current and temperature information, detected vehicle speed, master cylinder pressure information, lock-up clutch information, and information from various switches in the vehicle such as the stop lamp switch and courtesy switch.

Then, based on this information, when the EFI/CVT/IDS integrated ECU 11, which is performing idle stop control, detects that the driver has depressed the brake pedal in response to a red traffic light or the like and that the master cylinder pressure has reached a predetermined depression pressure or higher, it checks whether the predetermined stop conditions for idle stop control (for example, the stop lamps are on and the vehicle is traveling at or below a predetermined vehicle speed (e.g., 9 km/h) - equivalent to the "predetermined automatic engine stop conditions" of the present invention) are met. As a result, if the vehicle speed drops below the predetermined speed even if it does not come to a complete stop, it commands the engine ECU to stop the engine, and the engine ECU automatically stops the engine 3 by reducing the fuel throttle or the like.

Next, when the traffic light turns green, for example, and the driver releases the brake pedal, detecting that the master cylinder pressure has dropped to a predetermined release pressure, the idle-stop vehicle 1 checks whether the predetermined restart conditions for idle-stop control are met (e.g., the stop lamps are off and the doors are closed; these correspond to the "predetermined engine restart conditions" of the present invention). If it is determined that the predetermined restart conditions are met, the EFI/CVT/IDS integrated ECU 11 momentarily energizes and turns on relay 7, supplies power from battery 2 to starter 6, and automatically restarts the stopped engine 3.

Specifically, when restarting the engine 3, the EFI/CVT/IDS integrated ECU 11 controls the first driver IC 11a to supply power from the first driver IC 11a to the relay coil 7a. It also controls the second driver IC 11b to allow current from the relay coil 7a to flow to the ground provided in the second driver IC 11b. As a result, when restarting the engine 3, current flows from one end of the relay coil 7a to the other end, passes through a path connecting the other end to the second driver IC 11b, and falls to the ground provided in the second driver IC 11b. This energization of the relay coil 7a closes the relay switch 7b, and the engine 3 automatically starts (restarts).

After this, the engine 3 will alternate between automatically stopping when predetermined stop conditions are met during deceleration and automatically restarting when predetermined restart conditions are met.

Even if the above-mentioned predetermined restart conditions are not met in the idle-stop state, if information from the door opening/closing sensor 13 indicates that the door of the idle-stop vehicle 1 has changed from a closed state to an open state (corresponding to the "predetermined exit condition being met" in the present invention), or if information from the belt fastening/unfastening sensor 14 indicates that the seat belt has changed from a fastened state to an unfastened state (corresponding to the "predetermined exit condition being met" in the present invention), the EFI/CVT/IDS integrated ECU 11 will perform restart control of the engine 3. The EFI/CVT/IDS integrated ECU 11 periodically acquires information from the door opening/closing sensor 13 and the belt fastening/unfastening sensor 14 via the CAN 15.

At this time, the EFI/CVT/IDS integrated ECU 11 also determines the on/off state of each of the range SWs 8a through 8f (corresponding to the "switches" in this invention) that make up the shift range switch 8 (corresponding to the "shift range" in this invention). If the determination result is a specific determination result that P range SW 8a is on and the remaining range SWs 8b through 8f are all off, the EFI/CVT/IDS integrated ECU 11 determines that the shift position is definitely in P range and that the idle-stop vehicle 1 is in a safe state where restarting the engine 3 will not cause it to move, and performs restart control while prohibiting the output of an audible warning for the engine 3.

On the other hand, if the result of determining the on/off state of each range SW8a to range SW8f is something other than the specific determination result described above, it is unclear whether the shift position is in P range, and it is determined that restarting the engine 3 could cause the idling stop vehicle 1 to move. Therefore, in addition to controlling the restart of the engine 3, warning output control is performed to sound a warning sound from the speaker 16.

The on/off state of each range SW8a to range SW8f can be determined by detecting the potential of each port of the second driver IC 11b (port P1 (P), port P2 (R), port P3 (N), port P4 (D), port P5 (S), port P6 (B)). For example, when the P range SW8a is in the off state, the potential of port P1 (P) is at a high level, whereas when the P range SW8a is in the on state, the potential changes to a low level due to conduction between port P1 (P) and ground GND1. Therefore, if the EFI/CVT/IDS integrated ECU 11 detects that the potential of port P1 (P) is at a high level, it can determine that the P range SW8a is in the off state, and if it detects that the potential is at a low level, it can determine that the P range SW8a is in the on state. The on/off state of the other range switches 8b to 8f can be determined in a similar manner by detecting the potential levels of the corresponding ports (port P2 (R), port P3 (N), port P4 (D), port P5 (S), port P6 (B)).

In this embodiment, the EFI/CVT/IDS integrated ECU 11 periodically detects the potential level of each of the range switches 8a to 8f.

Next, with reference to the flowchart in Figure 3, the control process that occurs when a door is opened or a seatbelt is unfastened during idling stop will be described. This process is executed by the EFI/CVT/IDS integrated ECU 11.

During the period from when the predetermined stop conditions are met and the idle-stop vehicle 1 enters an idle-stop state until the predetermined restart conditions are met (the period during which the engine 3 remains automatically stopped), the EFI/CVT/IDS integrated ECU 11 determines whether the door of the idle-stop vehicle 1 has changed from a closed state to an open state, or whether the seat belt has changed from a fastened state to an unfastened state (step S1). If the determination result in step S1 is neither that the door of the idle-stop vehicle 1 has changed to an open state nor that the seat belt has changed to an unfastened state (NO in step S1), the EFI/CVT/IDS integrated ECU 11 waits until one of these determination results is reached. Based on information periodically acquired via the CAN 15 from the door opening/closing sensor 13 and the seat belt fastening/unfastening sensor 14, the EFI/CVT/IDS integrated ECU 11 determines whether the door of the idle-stop vehicle 1 has changed from a closed state to an open state, or whether the seat belt has changed from a fastened state to an unfastened state.

On the other hand, if the determination result in step S1 is that either the door of the idle-stop vehicle 1 has changed to an open state or the seat belt has changed to an unfastened state, the EFI/CVT/IDS integrated ECU 11 determines whether the state of the shift range switch 8 is abnormal (step S2).

If the determination result indicates that the state of the shift range switch 8 is abnormal (YES in step S3), the EFI/CVT/IDS integrated ECU 11 determines that it is unclear whether the shift position is in P range and that restarting the engine 3 could cause the idle-stop vehicle 1 to move, and executes engine 3 restart control and alarm output control to sound an alarm from the speaker 16 to alert the occupants (step S6).

In step S3, if the EFI/CVT/IDS integrated ECU 11 detects that only one of the range SWs 8a to 8f is on and all the others are off, it determines that the shift range switch 8 is in a normal state. On the other hand, if it detects that multiple of the range SWs 8a to 8f are on at the same time, or if it detects that all of the range SWs 8a to 8f are off, it determines that the shift range switch 8 is in an abnormal state.

However, to prevent erroneous determinations due to chattering of the range switches 8a through 8f, the EFI/CVT/IDS integrated ECU 11 does not determine that an abnormality exists (does not pass step S3 with a YES) simply because it detects that multiple range switches 8a through 8f are in the ON state or that all range switches 8a through 8f are in the OFF state at a certain interval. Instead, it determines that the shift range switch 8 is in an abnormal state if it detects that this state continues for a predetermined period of time (e.g., one second). Therefore, it passes step S3 with a NO until the predetermined period of time has elapsed.

If it is determined in step S3 that the shift range switch 8 is in a normal state (NO in step S3), the EFI/CVT/IDS integrated ECU 11 determines whether the P range SW 8a is in the ON state and whether all of the other range SWs 8b to 8f are in the OFF state (step S4).

If step S4 determines that the P range switch 8a is in the ON state and all of the other range switches 8b through 8f are in the OFF state, i.e., the first state (corresponding to the "first state" of the present invention), the EFI/CVT/IDS integrated ECU 11 determines that the shift position is definitely in the P range and that the idling-stop vehicle 1 is in a safe state where restarting the engine 3 will not move. The EFI/CVT/IDS integrated ECU 11 then executes engine 3 restart control while prohibiting alarm output from the speaker 16 (step S5), and terminates the process. Note that the determination in step S4 does not wait for the abnormal state of the shift range switch 8 to continue for a predetermined period of time, as is the case when determining that an abnormality exists in step S3, but rather executes engine 3 restart control upon determining that the first state is in the first state at a single determination timing.

On the other hand, if the result in step S4 is other than the first state (NO in step S4), it is unclear whether the shift position is in the P range, and it is determined that restarting the engine 3 could cause the idle-stop vehicle 1 to move. The system then immediately restarts the engine 3 and issues an alarm output control to sound an alarm through the speaker 16 to alert the occupants (step S6), after which the process ends. "Immediately" here means that the system executes engine 3 restart control and alarm output control when it determines at a single determination timing that the vehicle is in a state other than the first state, rather than waiting for the abnormal state of the shift range switch 8 to continue for a predetermined period of time, as is the case when determining that an abnormality exists in step S3.

Therefore, according to this embodiment, if it is determined that the occupant intends to exit the vehicle during an idle stop state, such as if the occupant opens the door of the idle stop vehicle 1 or unfastens their seatbelt, and the shift position is in the P range, the output of an alarm sound is prohibited, thereby preventing an intrusive alarm sound from being sounded in a safe state where the idle stop vehicle 1 will not start moving even if the engine 3 is restarted.

In addition, whether the shift position is in P range is determined by detecting the on/off state of all range switches 8a through 8f, which are provided for each range. This prevents erroneous determination due to chattering of each range switch 8a through 8f, and allows for earlier determination of the shift position compared to a method of determining whether the shift position is in P range by monitoring the state of each range switch 8a through 8f over a predetermined period of time. This allows for earlier output of an audible alarm when necessary.

The present invention is not limited to the above-described embodiments, and various modifications other than those described above are possible as long as they do not deviate from the spirit of the invention.

For example, in the above embodiment, when a situation arises in which it is determined that an occupant intends to exit the vehicle during an idle stop state and the shift position is not in P range, an alarm is sounded by the speaker 16 as a means of notifying the occupant. However, this information may also be displayed on the screen of the display device, or an alarm may be sounded in addition to the screen display, and various other means for notifying the occupant may be employed.

In addition, in the above embodiment, the EFI/CVT/IDS integrated ECU 11 directly controls the output of the warning sound from the speaker 16, but a request signal from the EFI/CVT/IDS integrated ECU 11 may be received by another ECU via the CAN 15, and the other ECU may control the speaker 16.

The present invention can be applied to various vehicles equipped with control means that stops a running engine when predetermined automatic engine stop conditions are met, and automatically restarts a stopped engine when predetermined engine restart conditions are met.

1. Idling stop vehicle (vehicle)
8 Shift range switch (shift range)
8a to 8f Range switch (switch)
11 EFI/CVT/IDS integrated ECU (control means)
16 Speaker (alarm output means)

Claims (1)

A vehicle control device including a control means for stopping a running engine when a predetermined engine automatic stop condition is met, and automatically restarting a stopped engine when a predetermined engine restart condition is met,
alarm output means for outputting an alarm to an occupant;
A plurality of shift ranges including a parking range are provided with individual switches, and the shift position can be detected based on the on/off state of each of the switches for the plurality of shift ranges,
the control means is capable of determining whether a predetermined condition indicating that an occupant intends to get off the vehicle is satisfied, and is capable of detecting the state of the switch for each of the plurality of shift ranges,
When the control means determines that the predetermined dismounting condition is satisfied during the period from when the predetermined engine automatic stop condition is satisfied to when the predetermined engine restart condition is satisfied,
When the states of the switches for the respective shift ranges detected by the control means are in a first state in which the switch for the parking range is in an on state and all of the switches for the other shift ranges are in an off state, output from the alarm output means is prohibited,
The vehicle control device is characterized in that, when the state of the switch for each of the plurality of shift ranges is other than the first state, an alarm is output from the alarm output means.