JP6451564B2 - Engine control device - Google Patents

Description

  The present invention relates to an engine control device applied to an engine mounted on a vehicle having an idling stop function.

  For the purpose of improving fuel efficiency and reducing exhaust gas, idling stop control is known in which an engine is stopped when a predetermined stop condition is satisfied, and then the engine is restarted when a predetermined start condition is satisfied.

  However, when the vehicle is traveling in a traffic jam, the automatic stop and restart of the engine are frequently repeated, which makes the driver feel uncomfortable. Accordingly, idling stop control is prohibited when the host vehicle is traveling in a traffic jam. For example, in Patent Document 1, when the state where the vehicle speed of the host vehicle is less than a predetermined value continues for a predetermined time or more, it is determined that the vehicle is traveling in a traffic jam and idling stop control is prohibited.

See JP 2001-55939 A

  However, if idling stop control is prohibited only on the condition that the vehicle speed of the host vehicle is lower than the predetermined value for a predetermined time or more, there is a risk that the opportunity for idling stop control may be lost in situations other than traffic jams. is there.

  The present invention has been made in view of the above, and a main object of the present invention is to provide a vehicle control device capable of appropriately performing idling stop control.

  The present invention is an engine control device having an idling stop control function for automatically stopping and restarting an engine mounted on a host vehicle, and includes an information acquisition unit that acquires detection information of an object in front of the host vehicle, A vehicle speed determination unit that determines that the vehicle speed of the vehicle is less than a predetermined value, and a detection information of a preceding vehicle within a predetermined distance in front of the own vehicle is acquired as the detection information when the vehicle speed of the own vehicle is determined to be less than the predetermined value. If it is determined that the host vehicle is traveling on a congested road, and if it is determined that the host vehicle is traveling on a congested road, it is determined that the automatic stop of the engine is prohibited. And a permission / rejection determination unit.

  According to the present invention, it is possible to improve the accuracy of determining whether there is a traffic jam as compared with the prior art that determines whether the vehicle is in a traffic jam based on the stop time of the host vehicle. Thereby, the unnecessary automatic stop of the engine during traveling in a traffic jam can be suppressed.

The schematic block diagram of an engine control system. Explanatory drawing regarding the propriety of the prediction of the stop time of the own vehicle. The flowchart regarding the rejection determination of idling stop control. The flowchart regarding the rejection determination of idling stop control. The flowchart regarding the determination process of idling stop control.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. The present embodiment embodies a vehicle equipped with an engine, and performs idling stop control using an electronic control unit (hereinafter referred to as ECU). FIG. 1 is a diagram showing a schematic configuration of an engine control system in the present embodiment.

  As shown in FIG. 1, the engine 11 is a spark ignition type gasoline engine, and includes an injector 12 and an ignition device 13 as a fuel injection unit for each cylinder. In addition, a starter device 14 is connected to the engine 11 as a starting device that applies initial rotation (cranking rotation) to the engine 11 when the engine is started. The engine 11 is not limited to a gasoline engine, and may be a diesel engine. Further, the starter device 14 may be an ISG (Integrated Starter Generator).

  The ECU 20 is an electronic control device including a known microcomputer and the like. Based on detection results of various sensors provided in the system, the ECU 20 performs various control such as fuel injection amount control by the injector 12 and ignition control by the ignition device 13. Engine control and drive control of the starter device 14 are performed.

  For details on the sensors, the ECU 20 detects an accelerator sensor 22 that detects an operation amount of an accelerator pedal as an accelerator operation member, a brake sensor 23 that detects an operation amount of a brake pedal as a brake operation member, and a vehicle speed. A speed sensor 24 and the like are connected, and signals from these sensors are sequentially input to the ECU 20.

  Further, the ECU 20 detects an object in front of the host vehicle (another vehicle (including a two-wheeled vehicle), a pedestrian, a signal device (a road signal, a crossing signal, a crossing barrier, etc.) and other road obstacles). A sensor 21 is connected. The image sensor 21 is installed in the vicinity of the upper end of the windshield of the host vehicle, etc., and captures a captured image by capturing an area that spreads in a predetermined range toward the front of the host vehicle every predetermined time. For example, a CCD camera, a monocular camera, a stereo camera, or the like is used for the image sensor 21.

  ECU20 acquires the detection information of the object ahead of the own vehicle by carrying out image processing of the picked-up image which the image sensor 21 acquired. The detection information includes information such as the distance to the object and the relative speed of the object. In addition, the ECU 20 specifies the type of object detected by performing known image processing such as template matching on the captured image.

  The ECU 20 performs idling stop control of the engine 11 based on information such as the vehicle speed, the accelerator pedal depression amount, the brake pedal depression amount, and the like. The idling stop control automatically stops the engine 11 when a predetermined engine automatic stop condition is satisfied, and restarts the engine 11 when a predetermined engine restart condition is satisfied.

  For example, the automatic stop condition of the engine 11 is satisfied when the accelerator pedal depression operation is released and the vehicle speed is reduced to a predetermined speed (for example, 10 km / h). The restart condition of the engine 11 is satisfied when the accelerator pedal depressing operation is started or the brake pedal depressing operation is released after the engine 11 is automatically stopped. It is also possible to adopt a configuration in which the engine control function and the idling stop control function are implemented by separate ECUs.

  By the way, when the host vehicle is traveling in a traffic jam, the automatic stop and restart of the engine 11 are frequently repeated, which makes the driver feel uncomfortable. Therefore, when the state where the vehicle speed of the host vehicle is less than the predetermined value continues for a predetermined time or more, it is determined that the vehicle is traveling with traffic and the automatic stop of the engine 11 can be prohibited.

  However, when the automatic stop of the engine 11 is prohibited only on the condition that the state where the vehicle speed of the host vehicle is less than the predetermined time continues for a predetermined time or longer, the automatic stop of the engine 11 is not performed even in a situation where the vehicle is not congested. May be banned. If the opportunity for the automatic stop of the engine 11 is lost in a situation other than a congested run, there is a concern that it may be a disadvantage in improving fuel consumption and reducing exhaust gas.

  On the other hand, when the host vehicle is traveling in a traffic jam, the preceding vehicle tends to be repeatedly approached every time the vehicle speed of the host vehicle becomes less than a predetermined value. Note that the situation in which the vehicle speed of the host vehicle is less than a predetermined value includes immediately before stopping the vehicle (during traveling) and immediately before traveling the vehicle (after stopping).

  Therefore, in the present embodiment, the distance (separation distance) between the preceding vehicle and the preceding vehicle is acquired every time the vehicle speed of the host vehicle becomes less than a predetermined value for travel and stop. And when it is repeated that the distance between vehicles becomes less than predetermined, it determines with it being a traffic jam. In this way, by adding the detection information in front of the host vehicle, it is possible to improve the determination accuracy of the traffic traveling.

  By the way, there are a situation where it is difficult to predict the stop time of the host vehicle and a situation where the stop time of the host vehicle can be predicted in the traffic jam. For example, a situation in which it is difficult to predict the stop time of the host vehicle includes traveling on a road without a signal device (for example, a highway). In this case, when the congestion line moves depends on the driving state of the preceding vehicle. That is, depending on the traveling state of the preceding vehicle, the traveling and stopping of the host vehicle are irregularly repeated such that the host vehicle re-transmits immediately after stopping or the stop time becomes longer. For this reason, as shown in FIG. 2A, the stop time of the host vehicle varies.

  In such a situation, the frequent repetition of the automatic stop and restart of the engine 11 leads to inconvenience to the driver. Further, when the state in which the stop time of the host vehicle is short is repeated, there is a concern that the influence of the battery loss or the like required for restart becomes greater than the effect of improving the fuel consumption by the automatic stop of the engine 11.

  Therefore, in the present embodiment, the automatic stop of the engine 11 is prohibited when the stop time of the host vehicle is not predictable.

  On the other hand, the situation in which the stop time of the host vehicle can be predicted includes traveling on a road with a signal device. In this case, since the running and stopping of the traffic jam train are repeated according to the instruction of the signal device, as shown in FIG. 2B, the stop time of the own vehicle is at least the stop time of the signal device according to the instruction of the signal device. The vehicle will stop in a longer time. Therefore, in this case, it is better to permit automatic stop of the engine 11 (permit idling stop control) even if the vehicle is traveling in a traffic jam.

  However, even in a situation where the stop time can be predicted, if the stop time of the host vehicle is short, there is a higher possibility that the loss due to battery driving or the like will increase than the effect of improving the fuel consumption.

  Therefore, in the present embodiment, during a traffic jam in which the stop time of the host vehicle can be predicted, if the stop time of the host vehicle (predicted stop time) is longer than a predetermined time, automatic stop of the engine 11 is permitted. On the other hand, if the stop time (predicted stop time) of the host vehicle is shorter than the predetermined time, the automatic stop of the engine 11 is prohibited.

  Next, an execution example of the above process will be described with reference to the flowcharts of FIGS. Note that the following processing is repeatedly performed by the ECU 20 at a predetermined cycle while an ignition switch (not shown) of the host vehicle is on.

  3 and 4 show the procedure for determining whether or not the idling stop control is permitted. First, in FIG. 3, it is determined whether or not it is a time when the vehicle speed V becomes smaller than a predetermined threshold Th1 (S11). If S11 is denied, the process is terminated. If S11 is affirmed, it is determined whether or not the inter-vehicle distance D1 between the host vehicle and the preceding vehicle has become smaller than a predetermined threshold Th2 (S12). If S12 is affirmed, the counter is incremented by 1 (S13). When S12 is denied, the counter is decremented by 1 (S14).

  Next, in FIG. 4, it is determined whether the vehicle is traveling in a traffic jam (S21). This process is affirmed when the counter is larger than the predetermined threshold Th3. If S21 is affirmed, it is determined in S22 and S23 whether or not the stop time of the host vehicle can be predicted.

  First, it is determined whether or not there is a signal device in front of the host vehicle (S22). This process is affirmed when a road signal or a crossing signal is detected in the image processing of the captured image. When S22 is affirmed, it is determined whether or not the distance D2 between the host vehicle and the signal device is less than the threshold Th4 (S23). This process can be specified from the information of the image target GT.

  When both S22 and S23 are affirmed, that is, when the stop time of the host vehicle can be predicted, it is determined whether or not the stop time T0 of the host vehicle is larger than a predetermined threshold Th5 (S24). ). When S24 is affirmed, the idling stop control permission flag is turned on (S25). On the other hand, when any of S22, S23, and S24 is denied, that is, when it is determined that the stop time of the host vehicle is not predictable, or when the stop time of the host vehicle can be predicted, the stop time T0 is predetermined. If it is shorter than the threshold Th5, the idling stop control permission flag is turned off (S26).

  On the other hand, when a negative determination is made in S21, that is, when the vehicle is not traveling in a traffic jam, the idling stop control permission flag is turned on (S25).

  FIG. 5 shows a processing procedure for idling stop control. First, it is determined whether or not an idling stop control permission flag is ON (S31). If S31 is affirmed, it is determined whether or not automatic stop by idling stop control is in progress (S32). When S32 is affirmed, it is determined whether the restart condition of the engine 11 is satisfied (S33). When S33 is affirmed, the engine 11 is restarted (S34).

  On the other hand, when S32 is denied, it is determined whether the automatic stop condition of the engine 11 is satisfied (S35). When S35 is affirmed, the engine 11 is automatically stopped (S36).

  In addition, a process is complete | finished when it denies by S31, S33, S35. In these cases, idling stop control is not performed.

  According to the above, the following excellent effects can be achieved.

  -In recent years, vehicles equipped with a function to acquire detection information of objects in front of the host vehicle have been put into practical use for the purpose of driving support of the host vehicle. In this technology, the detection information in front of the host vehicle is taken into account. And judging that it is in a traffic jam. Thereby, for example, it is possible to improve the accuracy of the determination that the vehicle is congested, as compared with the conventional technology that determines whether the vehicle is congested based on the stop time of the host vehicle. Thereby, the unnecessary automatic stop of the engine 11 during traveling in a traffic jam can be suppressed.

  -When the host vehicle is traveling on a congested road, the detection information of the preceding vehicle is repeatedly acquired each time the host vehicle travels and stops. Using this fact, it can be accurately determined that the host vehicle is traveling on a congested road.

  -Based on the detection information acquired by an information acquisition part, the stop time in the state which the own vehicle has stopped is estimated. At this time, if the stop time can be predicted, an effect such as improvement in fuel consumption can be obtained by permitting automatic stop of the engine 11. On the other hand, if the stop time is not predictable, it becomes as soon as the traffic queue moves, and the vehicle may retransmit immediately after the own vehicle stops. Therefore, in this case, by prohibiting the automatic stop of the engine 11, it is possible to suppress the occurrence of inconvenience that the automatic stop and restart of the engine 11 are frequently repeated.

  Since the stop time of the host vehicle is predictable and the stop time of the host vehicle is secured to some extent, the automatic stop of the engine 11 is permitted. Can be increased. On the other hand, if the stop time of the host vehicle can be predicted and the stop time is short, the unnecessary automatic stop of the engine 11 can be suppressed.

  ・ When the vehicle is stopped due to the signal device during traffic jams, the host vehicle is repeatedly driven and stopped according to the switching of the signal device. Time can be predicted.

  The present invention is not limited to the above, and may be implemented as follows. In the following description, the same components as those described above are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the above, as the detection information, the inter-vehicle distance from the preceding vehicle in the period from when the host vehicle travels from the stopped state to the next stopped state may be acquired. That is, when the host vehicle is traveling on a congested road, it is considered that the inter-vehicle distance with respect to the preceding vehicle does not increase so much even if the host vehicle shifts from the stopped state to the traveling state. Therefore, when the host vehicle travels from the stop state and acquires the inter-vehicle distance with the preceding vehicle in the period until the next stop state, and the inter-vehicle distance is less than the predetermined distance, the host vehicle travels on the congested road. Can be determined.

  -In the above, on the condition that the host vehicle is in a stopped state (vehicle speed is zero), whether the host vehicle is traveling in a traffic jam according to whether or not the situation in which the preceding vehicle is approaching is repeated. You may judge.

  -In the above, if the preceding vehicle is in the approaching state when the vehicle speed of the own vehicle becomes less than the predetermined value (or the own vehicle is in the stopped state), even if the situation in which the preceding vehicle is in the approaching state is not repeated, It may be determined that the vehicle is traveling in a traffic jam.

  In the flowchart of FIG. 4 described above, each process of S22 to S24 may be omitted. That is, when it is determined that the vehicle is traveling in traffic jam in S21, the idling stop control may be prohibited regardless of whether or not the stop time of the host vehicle can be predicted. Alternatively, when it is determined that the stop time of the host vehicle can be predicted regardless of the stop time of the host vehicle by omitting the process of S24, the idling stop control may be permitted.

  -In the above, when the host vehicle is traveling on a road with a signal device, if there is a distance between the host vehicle and the signal device, traveling and stopping of the host vehicle are constant according to the instructions of the signal device. It repeats with a period. Therefore, it may be determined whether or not the stop time of the host vehicle can be predicted based on whether or not the traveling and stopping of the host vehicle are repeated at a constant cycle. For example, the cycle of the automatic stop and restart of the engine 11 is stored in the storage unit. Then, it is possible to determine whether the stop time of the host vehicle can be predicted using the cycle of the automatic stop and restart of the engine 11 stored in the storage unit.

  In the above, information such as that the traffic signal is a stop signal (red signal or the like) or that the level crossing barrier is down may be acquired as detection information of the signaling device.

  In the above, the brake lamp of the preceding vehicle is detected by image processing of the captured image by the ECU 20. Then, when the flashing of the brake lamp of the preceding vehicle has a constant cycle, it can be determined that the stop time of the host vehicle can be predicted. On the other hand, if the blinking of the brake lamp of the preceding vehicle is irregular, it can be determined that the stop time of the host vehicle cannot be predicted.

  In the above, the detection information of the preceding vehicle is acquired using the image sensor 21. In addition to this, the detection information of the preceding vehicle can be acquired using various sensors that can detect an object ahead of the host vehicle. For example, the detection information of the preceding vehicle is acquired using a radar sensor. The radar sensor detects an object in front of the host vehicle using a directional electromagnetic wave such as a millimeter wave or a laser, and is attached so that the optical axis thereof faces the front of the host vehicle. The radar sensor scans an area extending in a predetermined range toward the front of the vehicle every predetermined time with a radar signal, and receives an electromagnetic wave reflected from the surface of an object outside the vehicle, thereby receiving a distance from the object and relative to the object. The speed and the like are acquired as detection information.

  In the above, it is assumed that the type of object cannot be specified using detection information depending on the type of sensor that detects the object (for example, a radar sensor). Therefore, in this case, a white line on the traveling path of the host vehicle is detected by image processing of the captured image. The white line detection method is well known and will not be described in detail. And among the detected objects, you may detect the object which exists in the traveling path of the own vehicle as a preceding vehicle.

  In the above configuration, in the configuration in which the radar sensor is mounted on the vehicle, the distance D2 between the host vehicle and the stop member in S23 of FIG. 4 may be detected using the radar sensor.

  DESCRIPTION OF SYMBOLS 11 ... Engine, 20 ... ECU, 21 ... Image sensor.

Claims (6)

An engine control device having an idling stop control function for automatically stopping and restarting an engine mounted on a host vehicle,
An information acquisition unit for acquiring detection information of an object in front of the host vehicle;
A vehicle speed determination unit that determines that the vehicle speed of the host vehicle is less than a predetermined value;
When it is determined that the vehicle speed of the host vehicle is less than a predetermined value and detection information of a preceding vehicle within a predetermined distance in front of the host vehicle is acquired as the detection information, the host vehicle is traveling on a congested road A traffic jam judgment unit for judging,
A permission / rejection determination unit that determines that the automatic stop of the engine is prohibited when it is determined that the host vehicle is traveling on a congested road;
Equipped with a,
The engine control device determines that the own vehicle is traveling on a congested road when the detection information of the preceding vehicle is repeatedly acquired every time the own vehicle travels and stops . An engine control device having an idling stop control function for automatically stopping and restarting an engine mounted on a host vehicle,
An information acquisition unit for acquiring detection information of an object in front of the host vehicle;
A vehicle speed determination unit that determines that the vehicle speed of the host vehicle is less than a predetermined value;
When it is determined that the vehicle speed of the host vehicle is less than a predetermined value and detection information of a preceding vehicle within a predetermined distance in front of the host vehicle is acquired as the detection information, the host vehicle is traveling on a congested road A traffic jam judgment unit for judging,
A permission / rejection determination unit that determines that the automatic stop of the engine is prohibited when it is determined that the host vehicle is traveling on a congested road ;
A stop time determination unit that determines whether the stop time can be predicted in a state where the host vehicle is stopped based on the detection information acquired by the information acquisition unit;
When it is determined that the host vehicle is traveling on a congested road, the permission / refusal determination unit prohibits the automatic stop of the engine if the stop time cannot be predicted, and the stop time can be predicted. An engine control device that permits automatic stop of the engine if any . When the stop time of the host vehicle is predictable, the permission / refusal determination unit permits the automatic stop of the engine if the stop time of the host vehicle is longer than a predetermined time, and if the stop time is shorter than the predetermined time, The engine control device according to claim 2 , wherein automatic stop of the engine is prohibited. The information acquisition unit acquires detection information of a signal device that regulates vehicle travel on a road as the detection information,
The engine control device according to claim 2 or 3 , wherein the stop time determination unit determines that the stop time can be predicted if detection information of the signal device is acquired by the information acquisition unit. 5. The traffic congestion determination unit determines that the host vehicle is traveling on a congested road when the detection information of the preceding vehicle is repeatedly acquired each time the host vehicle travels and stops. The engine control apparatus according to claim 1. The information acquisition unit acquires detection information of the object using a captured image acquired by an imaging unit that continuously images the front area of the host vehicle or a signal acquired by transmission / reception of a carrier wave in the front area of the host vehicle. The engine control device according to any one of claims 1 to 5 .

Images