JP4100285B2 - Vehicle engine control device - Google Patents

Description

  The present invention belongs to the technical field of a vehicle engine control device, and more particularly, to a vehicle engine control device in an environment-friendly vehicle such as an idle stop vehicle in which the engine is automatically stopped and restarted.

  In general, in an idle stop vehicle that improves fuel consumption, reduces emissions, suppresses noise and vibration, etc., a predetermined engine stop condition is established when the vehicle stops, for example, the vehicle speed is zero and the brake pedal is depressed. When the engine is automatically stopped, the engine is automatically restarted when a predetermined engine restart condition is satisfied in the automatic stop state of the engine.

  In that case, conventionally, as a restart condition of the engine, as disclosed in Patent Document 1, when the brake pedal is operated to be released (return operation) exceeding a predetermined amount, the driver is required to start. It was customary for the engine to be automatically restarted as having the will.

JP 2001-227373 A

  However, in the conventional engine restart condition described above, the engine is restarted as a result of the brake pedal release operation, so when the engine is restarted, the braking force of the vehicle is weakened. Even if the vehicle is not depressed, the vehicle may move forward due to the engine output. As a result, in order to prevent the vehicle from moving forward, the driver depresses the brake pedal immediately after releasing the brake pedal, and the driver depresses the brake pedal within a short time. The reverse operation of the opening operation and the stepping operation is continuously performed, so that the brake operability is lowered. Such re-depression of the brake pedal and the accompanying decrease in operability are caused when the vehicle is stopped in an environment where it is desired to suppress the forward movement of the vehicle accompanying the restart of the engine. If the vehicle moves forward, it occurs even more frequently when the vehicle stops in an unfavorable environment in terms of safety.

  An object of the present invention is to prevent the vehicle from moving forward when the engine is restarted and to prevent the driver from damaging the brake operability. Hereinafter, the present invention will be described in detail including other problems.

That is, the invention according to claim 1 of the present application includes a driving state detecting means for detecting a plurality of vehicle driving states including at least a vehicle speed and a brake operation state, and when the vehicle is stopped from the vehicle driving state detected by the detecting means. The engine is automatically stopped when it is determined that the predetermined engine stop condition is satisfied, and the engine is automatically restarted when it is determined that the predetermined engine restart condition is satisfied in the engine automatic stop state. A vehicle engine control device comprising a restarting means, wherein the engine automatic stop / restarting means has a brake stepping speed equal to or higher than a predetermined speed and a brake stepping amount of a predetermined amount as the engine restarting condition; together they are configured to restart the engine when it exceeds, stop environmental test for detecting the stop environment when the vehicle is stopped And a predetermined amount correcting means for increasing and correcting the predetermined amount of brake depression when compared to when the vehicle is stopped at the intersection or immediately before the pedestrian crossing by the detecting means. It is characterized by providing .

Next, the invention according to claim 2 is a driving state detecting means for detecting a plurality of vehicle driving states including at least a vehicle speed and a brake operation state, and the detecting means, as in the case of the invention according to claim 1. When it is determined that the predetermined engine stop condition is satisfied when the vehicle is stopped from the vehicle operating state detected in step 1, the engine is automatically stopped, and it is determined that the predetermined engine restart condition is satisfied in the engine automatic stop state. A vehicle engine control device comprising an engine automatic stop / restart means for automatically restarting the engine, wherein the engine automatic stop / restart means has a predetermined brake depression speed as the engine restart condition. with depression amount of the brake at a rate above it is configured to restart the engine when it exceeds a predetermined amount, the stop when the vehicle is stopped Stopping environment detecting means for detecting a boundary, and when the vehicle is stopped due to traffic jam by the detecting means and the distance from the preceding vehicle is more than a predetermined distance, the brake is compared with the case where it is not detected. characterized in that it comprises a predetermined quantity correcting means for decreasing correcting the predetermined amount of depression amount.

  First, according to the first aspect of the present invention, in an environment-friendly vehicle such as an idle stop vehicle in which the engine is automatically stopped and restarted, the brake depressing speed is a predetermined speed as the engine restart condition. Since the engine is restarted when the brake depression amount exceeds the predetermined amount as described above, the vehicle braking force is sufficiently secured when the engine is restarted, and the accelerator pedal depression is also performed. Therefore, the vehicle is reliably prevented from moving forward by the engine output. Therefore, it is avoided that the driver continuously performs the reverse operation of the brake pedal opening operation and the stepping operation within a short time, and the driver's brake operability is not deteriorated.

  Here, as a condition for restarting the engine, the condition that the brake depression speed is equal to or higher than the predetermined speed is not simply restarted when the brake depression amount exceeds a predetermined amount. This is to limit the brake depressing operation with a clear intention of the driver, and to eliminate the slow brake depressing operation of the driver unconsciously. When the engine is restarted in the latter case, it is not preferable because excessive discomfort occurs.

In particular , according to the first aspect of the present invention, when the vehicle is stopped in an intersection, for example, waiting for a right turn, or stopped just before a pedestrian crossing, in other words, the vehicle is When the vehicle is stopped in an environment where the forward movement of the vehicle accompanying the start is strongly suppressed, the predetermined amount of the brake depression amount as the engine restart condition is relatively increased, so that when the engine is restarted The braking force of the vehicle is further increased, and the vehicle is further reliably prevented from moving forward by the engine output.

  On the other hand, when the vehicle is not stopped in the above environment, the predetermined amount of the brake depression amount as the engine restart condition is not relatively increased, so that the braking force of the vehicle when the engine is restarted Becomes relatively small, and start response of the vehicle is ensured.

Next, according to the invention described in claim 2 , as in the invention described in claim 1, in an environment-friendly vehicle such as an idle stop vehicle in which the engine is automatically stopped and restarted, As a restart condition, since the engine is restarted when the brake stepping speed is equal to or higher than the predetermined speed and the brake stepping amount exceeds the predetermined amount, the braking force of the vehicle is reduced when the engine is restarted. Sufficiently secured and no depression of the accelerator pedal prevents the vehicle from moving forward due to engine output. In that case, according to the second aspect of the present invention, when the vehicle is stopped due to traffic jams and the distance from the preceding vehicle is equal to or greater than the predetermined distance, in other words, the vehicle restarts the engine. When the vehicle is stopped in an environment where it is not necessary to strongly suppress the forward movement of the vehicle, the predetermined amount of brake depression as the engine restart condition is relatively reduced. The braking force of the vehicle becomes relatively small, and the start response of the vehicle is ensured.

Hereinafter, the present invention will be described in more detail through the best mode for carrying out the invention.

  In the present embodiment, the present invention is applied to the vehicle 1 shown in FIG. The vehicle 1 is an idle stop vehicle. When the predetermined engine stop condition J1 is satisfied when the vehicle 1 stops, the engine 10 is automatically stopped (start / execution of idle stop). When the predetermined engine restart condition J2 is satisfied in the automatic stop state (idle stop state) of the engine 10, the engine 10 is automatically restarted (release of the idle stop). In the present embodiment, the engine stop condition (idle stop condition) J1 is that the vehicle speed is zero and the brake pedal 30 is depressed. The engine restart condition (idle stop release condition) J2 is that the depression speed of the brake pedal 30 is equal to or higher than a predetermined speed and the depression amount of the brake pedal 30 exceeds a predetermined amount (idle stop cancellation threshold). .

  The engine control control unit 20 of the vehicle 1 detects a brake operation amount detection means (for example, the pedal 30 of the pedal 30) that detects a depression amount, a release amount (return amount), a depression speed, a release speed (return speed), or the like of the brake pedal 30. 31 composed of a stroke sensor, a brake pressure sensor, etc.), a vehicle speed detecting means for detecting the vehicle speed of the vehicle 1 (for example, composed of a vehicle speed sensor) 32, a current position detecting means for detecting the current position of the vehicle 1 GPS: configured with a global positioning system, etc.) 33, infrastructure information receiving means for receiving infrastructure information around the vehicle 1 (for example, configured with a dedicated antenna, etc.) 34, and an inter-vehicle distance from a preceding vehicle ahead Various signals are input from an inter-vehicle distance detecting means (for example, constituted by a millimeter wave radar) 35 or the like for detecting the. The engine control control unit 20 can access map information storage means (for example, a CD-ROM or DVD-ROM storing map software) 40 for storing domestic map information. The map information is read from the means 40.

  Based on these various signals and information, the engine control control unit 20 determines whether or not the engine stop condition J1 is satisfied by the idle stop execution determination unit 21, and the idle stop cancellation determination unit 22 It is determined whether the engine restart condition J2 is satisfied, the vehicle stop environment detection unit 23 detects the environment where the vehicle 1 is stopped, and the restart condition setting unit 24 sets the engine restart condition J2 Change according to the situation. Based on these control results, the engine control control unit 20 outputs a control signal to the fuel injection valve 11 and the spark plug 12 of the engine 10 and displays the display signal on the display device 50 disposed in front of the driver's seat. Is output.

  Next, an example of specific operations of automatic stop and automatic restart of the engine 10 in the environment-friendly vehicle 1 will be described with reference to the flowchart of FIG. First, in step S1, after inputting various signals, it is determined in step S2 whether or not an idle stop is being performed. If NO (if not in an idle stop), an idle stop condition J1 is established in step S3. It is determined whether or not. Here, the idle stop condition J1 is that the vehicle speed is zero and the brake pedal 30 is depressed as described above. As a result, in the case of NO (when the idle stop condition J1 is not satisfied), the process returns as it is, and in the case of YES (when the idle stop condition J1 is satisfied), the idle stop is executed in step S4. (Automatic stop of the engine 10: fuel injection stop and ignition stop) and return.

  On the other hand, in the case of YES in step S2 (when idling stop is being performed), in step S5, it is determined whether or not the stop environment of the vehicle 1 is in the intersection or immediately before the pedestrian crossing. That is, it is determined whether the vehicle 1 is stopped at the intersection, for example, waiting for a right turn or just before the crosswalk.

  In addition, as described above, the vehicle stop environment detection unit 23 of the engine control control unit 20 determines such a vehicle 1 stop environment. In this case, the vehicle stop environment detection unit 23 Signals and information obtained from the current position detection means 33, the infrastructure information reception means 34, the inter-vehicle distance detection means 35, the map information storage means 40, etc. are fully utilized.

  As a result, when the determination in step S5 is YES, the vehicle 1 stops in an environment in which the forward movement accompanying the restart of the engine 10 is strongly suppressed, that is, in an environment that is not preferable in terms of safety when the vehicle 1 moves forward. In step S6, the idle stop cancellation threshold value is increased and corrected. That is, a value obtained by adding the increase correction amount α to a predetermined reference value is set as an idle stop cancellation threshold value.

  On the other hand, if NO in step S5, it is determined in step S7 whether the stopping environment of the vehicle 1 is congested and the distance from the preceding vehicle is equal to or greater than a predetermined distance. That is, it is determined whether the vehicle 1 is stopped due to a traffic jam and the distance between the vehicle and the preceding vehicle is more than a predetermined distance. As a result, in the case of YES, it is determined that the vehicle 1 is stopped in an environment where it is not necessary to strongly suppress the forward movement associated with the restart of the engine 10, and in step S8, the idle stop cancellation threshold value is corrected to decrease. . That is, a value obtained by subtracting the decrease correction amount β from a predetermined reference value is set as an idle stop cancellation threshold value.

  On the other hand, if the answer is NO in step S7, it is determined that the vehicle 1 is stopped in a normal environment. Then, the predetermined reference value is directly adopted as the idle stop cancellation threshold without correcting the idle stop cancellation threshold.

  In any case, in step S9, it is determined whether or not the depression speed of the brake pedal 30 is equal to or higher than a predetermined speed and the depression amount of the brake pedal 30 exceeds the idle stop cancellation threshold. That is, it is determined whether or not the idle stop cancellation condition J2 is satisfied. As a result, in the case of NO (when the idle stop condition J2 is not satisfied), the process returns as it is (continuation of idle stop), and in the case of YES (when the idle stop condition J2 is satisfied), in step S10. Then, the idle stop is canceled (automatic restart of the engine 10: fuel injection restart and ignition restart), and the process returns.

  Here, the predetermined speed of the depression speed of the brake pedal 30 as the idle stop cancellation condition J2 is experimentally determined in advance when the driver depresses the brake pedal 30 with intention, for example. It can be obtained or can be obtained by simulation or the like.

  Thus, in this embodiment, as is clear from steps S9 to S10, as the engine restart condition J2, the depression speed of the brake pedal 30 is equal to or higher than a predetermined speed and the depression amount of the brake pedal 30 is a predetermined idle stop. When the release threshold is exceeded, the engine 10 is automatically restarted (time t1 in FIG. 3). Therefore, the braking force of the vehicle 1 is sufficiently ensured when the engine 10 is restarted. Moreover, since the brake pedal 30 is depressed, there is no possibility that an accelerator pedal (not shown) is depressed simultaneously. Therefore, the vehicle 1 is reliably prevented from moving forward by the output of the engine 10. As a result, it is avoided that the driver continuously performs the reverse operation of the release operation and the depression operation of the brake pedal 30 within a short time, and the operability of the driver's brake pedal 30 is not deteriorated.

  Further, as is clear from steps S5 to S6, when the vehicle 1 is stopped in an environment where it is desired to suppress the forward movement accompanying the restart of the engine 10, the idle stop cancellation threshold value as the engine restart condition J2 is corrected to increase. Is done. Therefore, the braking force of the vehicle 1 when the engine 10 is restarted is further increased, and the vehicle 1 is further reliably prevented from moving forward by the output of the engine 10.

  On the other hand, as is clear from steps S7 to S8, when the vehicle 1 is stopped in an environment where it is not necessary to strongly suppress the forward movement accompanying the restart of the engine 10, it is safe even if the vehicle 1 moves forward. Therefore, the idle stop cancellation threshold value as the engine restart condition J2 is reduced and corrected. Therefore, the braking force of the vehicle 1 when the engine 10 is restarted becomes relatively small, and the start response of the vehicle 1 is ensured.

  When the stop environment of the vehicle 1 is a normal stop environment, the idle stop cancellation threshold value as the engine restart condition J2 is neither increased nor decreased (steps S6 and S8 are skipped). Therefore, a problem that the idle stop cancellation threshold value is increased excessively and the start response of the vehicle 1 is unnecessarily impaired is avoided.

Next, an operation example of automatic stop and automatic restart of the engine 10 in the environment-friendly vehicle 1 related to the embodiment of the present invention will be described according to the flowchart of FIG. First, in step S21, various signals are input, and in step S22, it is determined whether or not an idle stop is being performed. If NO (not in an idle stop), the idle stop condition J1 is satisfied in step S23. It is determined whether or not. Here, as described above, the idle stop condition J1 is that the vehicle speed is zero and the brake pedal 30 is depressed. As a result, in the case of NO (when the idle stop condition J1 is not satisfied), the process returns as it is, and in the case of YES (when the idle stop condition J1 is satisfied), the idle stop is executed in step S24. (Automatic stop of the engine 10: fuel injection stop and ignition stop) and return.

  On the other hand, if YES in step S22 (when idling is stopped), it is determined in step S25 whether the stop environment of the vehicle 1 is an environment in which it is desired to suppress the forward movement of the vehicle 1 due to the restart of the engine 10 (vehicle 1 is stopped at the intersection or waiting just before the pedestrian crossing, for example by waiting for a right turn. As a result, in the case of YES, it is determined that it is not preferable in terms of safety if the vehicle 1 moves forward, and in step S26, the engine 10 is operated when the brake pedal 30 is depressed as an idle stop release condition. The restart is adopted (release condition J2a), and the display device 50 is used to notify the driver through visual and auditory sense that the release condition J2a having such contents is adopted.

  Here, as the idle stop cancellation condition, the engine 10 is restarted when the brake pedal 30 is depressed and the depression speed of the brake pedal 30 is equal to or higher than a predetermined speed, according to the first control example. (Cancellation condition J2a ′).

  In step S27, it is determined whether or not the amount of depression of the brake pedal 30 exceeds the predetermined idle stop cancellation threshold A. That is, it is determined whether or not the idle stop cancellation condition J2a is satisfied. As a result, in the case of NO (when the idle stop condition J2a is not satisfied), the process returns as it is (continuation of the idle stop), and in the case of YES (when the idle stop condition J2a is satisfied), in step S28. Then, the idle stop is canceled (automatic restart of the engine 10: fuel injection restart and ignition restart), and the process returns.

  On the other hand, in the case of NO in the above step S25, it is determined that even if the vehicle 1 moves forward, the safety result is not so serious, and in step S29, the brake pedal 30 is set as an idle stop cancellation condition. When the vehicle is opened, the engine 10 is restarted (release condition J2b), and the display device 50 is used to notify the driver through the visual and auditory sense that such a release condition J2b is adopted. To do.

  In step S30, it is determined whether or not the release amount (return amount) of the brake pedal 30 is greater than a predetermined idle stop cancellation threshold value B. That is, it is determined whether or not the idle stop cancellation condition J2b is satisfied. As a result, in the case of NO (when the idle stop condition J2b is not satisfied), the process returns as it is (continuation of the idle stop), and in the case of YES (when the idle stop condition J2b is satisfied), in step S28. Then, the idle stop is canceled (automatic restart of the engine 10: fuel injection restart and ignition restart), and the process returns.

Thus, in this operation example, as is clear from steps S25 to S28, when the vehicle 1 is stopped in an environment where it is desired to suppress the forward movement of the vehicle 1 accompanying the restart of the engine 10, the engine restart condition When the brake pedal 30 is depressed, the engine 10 is restarted (time t11 in FIG. 5). Therefore, as in the operation example of the embodiment of FIGS. 2 and 3, the braking force of the vehicle 1 is sufficiently ensured when the engine 10 is restarted. Moreover, since the brake pedal 30 is depressed, an accelerator pedal (not shown) is not depressed simultaneously. Therefore, the vehicle 1 is reliably prevented from moving forward by the output of the engine 10. As a result, it is avoided that the driver continuously performs the reverse operation of the release operation and the depression operation of the brake pedal 30 within a short time, and the operability of the driver's brake pedal 30 is not deteriorated.

  On the other hand, as is clear from steps S25, S29 to S30, S28, on the contrary, when the vehicle 1 is stopped in an environment where it is not necessary to suppress the forward movement of the vehicle 1 accompanying the restart of the engine 10, the engine As a restart condition, the engine 10 is restarted when the brake pedal 30 is released (time t12 in FIG. 5). Therefore, in this case, the driver's intention to start is appropriately reflected, and the start response of the vehicle 1 is ensured.

  As is clear from steps S26 and S29, in any case, the driver is notified of the engine restart conditions J2a and J2b that change in accordance with the stop environment of the vehicle 1. The engine restart condition changes in accordance with the stopping environment of 1 and it is less likely to feel uncomfortable that the restart timing of the engine 10 actually changes.

  The embodiment described above is the best mode for carrying out the present invention, but it goes without saying that it can still be changed according to the situation such as the vehicle type and the purpose of use. For example, as an example of an environment where it is desired to suppress the forward movement of the vehicle, a waiting for the head of a railroad crossing may be added.

In the above embodiment, the release threshold value when the brake pedal 30 is depressed is the value of the depression amount of the brake pedal 30 itself ( idle stop release threshold value in FIG. 3 ). It is also possible to set the amount of depression from the amount of depression of the brake pedal 30 at the time.

  As described above, according to the present invention, since the forward movement of the vehicle at the time of engine restart is reliably prevented, the brake operability is not reduced, for example, the driver depresses the brake pedal again. INDUSTRIAL APPLICABILITY The present invention has wide industrial applicability in the general technical field of vehicle engine control devices including environment-friendly vehicles such as idle stop vehicles.

It is a control system figure of the engine for vehicles concerning the best form for carrying out the present invention. It is a flowchart which shows the operation example of the automatic stop and automatic restart of the engine of the said vehicle. It is a time chart in the same operation example . It is a flowchart which shows the operation example of the automatic stop and automatic restart of the engine of the vehicle relevant to this invention . It is a time chart in the same operation example .

Explanation of symbols

1 Idle stop vehicle (environmentally friendly vehicle)
10 engine 20 engine control unit (engine automatic stop / restart means)
21 idle stop execution determination unit 22 idle stop release determination unit 23 vehicle stop environment detection unit (stop environment detection means)
24 restart condition setting unit (predetermined amount correction means)
30 Brake pedal 31 Brake operation amount detection means (driving state detection means)
32 Vehicle speed detection means (driving condition detection means)
33 Current position detection means 34 Infrastructure information reception means 35 Inter-vehicle distance detection means 40 Map information storage means 50 Display device (notification means)

Claims (2)

A driving state detection means for detecting a plurality of vehicle driving states including at least a vehicle speed and a brake operation state; and when it is determined from the vehicle driving state detected by the detection means that a predetermined engine stop condition is satisfied when the vehicle is stopped Is an engine control device for a vehicle having an engine automatic stop / restart means that automatically stops the engine and automatically restarts the engine when it is determined that a predetermined engine restart condition is satisfied in the engine automatic stop state. The engine automatic stop / restart means is configured to restart the engine when the brake depression speed exceeds a predetermined speed and the brake depression amount exceeds a predetermined amount as the engine restart condition. and with that, the stop environment detection means for detecting the stop environment during stop of the vehicle, the vehicle is also the intersection detecting means When detected to be stopped just before the crosswalk, than when not detected, a vehicle engine control, characterized in that it comprises a predetermined quantity correcting means for increasing correcting the predetermined amount of the brake depression amount apparatus. A driving state detection means for detecting a plurality of vehicle driving states including at least a vehicle speed and a brake operation state; and when it is determined from the vehicle driving state detected by the detection means that a predetermined engine stop condition is satisfied when the vehicle is stopped Is an engine control device for a vehicle having an engine automatic stop / restart means that automatically stops the engine and automatically restarts the engine when it is determined that a predetermined engine restart condition is satisfied in the engine automatic stop state. The engine automatic stop / restart means is configured to restart the engine when the brake depression speed exceeds a predetermined speed and the brake depression amount exceeds a predetermined amount as the engine restart condition. and with that, the stop environment detection means for detecting the stop environment when the vehicle is stopped, stop the vehicle is in traffic jam detecting means And a predetermined amount correcting means for reducing and correcting the predetermined amount of brake depression when compared with a case where the distance to the preceding vehicle is greater than or equal to a predetermined distance. A vehicle engine control device.

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