JP2008296798A - Control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the fuel economy of an engine by reducing the stop operations (start operations) of a vehicle at a red light. <P>SOLUTION: An ECU 17 calculates a traveling distance from a current position of a vehicle to the next traffic light (the nearest traffic light) installed on a scheduled traveling route, and acquires a traffic light change timing information (when a green light of the next traffic light starts or ends). Furthermore, the ECU 17 calculates a recommended speed (so that the vehicle is able to reach the traffic light during the green light) at which the vehicle is able to pass through the traffic light during the green light of the next traffic signal based on the traveling distance to the next traffic light and a traffic light change timing information, and a recommended speed display part 16 displays the recommended speed. Thus, it is possible to urge a driver to run the vehicle at the recommended speed, and the vehicle is able to pass through the traffic light during the green light more frequently without stopping at the traffic light when the driver performs an accelerating operation to run the vehicle at the recommended speed. Therefore, it is possible to reduce the stop operations of the vehicle at a red light. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle control device that uses information of traffic lights installed in a planned travel route of a vehicle.

  2. Description of the Related Art Recently, in an internal combustion engine mounted on a vehicle, as described in Patent Document 1 (Japanese Patent No. 3709746), an automatic stop / start device (so-called idling stop) is used for the purpose of reducing fuel consumption and exhaust emission. Equipment). This automatic stop / start device automatically stops the internal combustion engine when the driver stops the vehicle and a predetermined automatic stop condition is satisfied, and then the driver performs an operation to start the vehicle. Thus, the internal combustion engine is automatically restarted when a predetermined automatic start condition is satisfied.

  However, when the vehicle is frequently stopped and started repeatedly in a traffic jam or the like, if the automatic stop / automatic start of the internal combustion engine is frequently repeated, there is a possibility that noise or vehicle start delay may occur.

As a countermeasure, in Patent Document 1, the degree of congestion on the traveling path of the host vehicle is determined based on the image data of the scenery around the host vehicle, and when the degree of congestion is equal to or higher than a predetermined level, the internal combustion engine is automatically stopped. By preventing the condition from being satisfied, the internal combustion engine is not automatically stopped when the vehicle is frequently stopped and started in a traffic jam or the like.
Japanese Patent No. 3709746 (first page to third page, etc.)

  In general, if the number of stops of the vehicle in the travel route of the vehicle is large, the number of vehicle starts (that is, the number of accelerations) that causes a deterioration in fuel consumption increases, and the average fuel consumption of the entire travel route of the vehicle also deteriorates. However, the technique of the above-mentioned patent document 1 is designed to prevent the vehicle from being stopped or started frequently in a traffic jam or the like by preventing the automatic stop condition of the internal combustion engine from being satisfied when the degree of congestion is equal to or higher than a predetermined level. This is a technique for preventing the internal combustion engine from being automatically stopped. Since the number of vehicle stops (starts) due to a red signal from the traffic light cannot be decreased, the internal combustion engine is not increased due to an increase in the number of stops (starts) of the vehicle. The problem of fuel consumption deterioration is still not solved and the demand for fuel efficiency improvement cannot be satisfied.

  The present invention has been made in view of such circumstances, and therefore, an object of the present invention is to control a vehicle capable of improving fuel efficiency by reducing the number of times of stopping of the vehicle due to a red signal of a traffic light as compared with the conventional one. To provide an apparatus.

  In order to achieve the above object, the invention according to claim 1 calculates the travel distance from the current location of the vehicle to the next traffic light installed in the planned travel route by the traffic light distance information calculating means, and The start time of the green light and / or the end time of the green light (hereinafter collectively referred to as “traffic light change time information”) are acquired by the traffic light change time information acquisition means, and the travel distance to the next traffic light and the traffic light change time information The recommended vehicle speed at which the vehicle can pass the traffic signal during the period of the green signal of the next traffic light is calculated by the recommended vehicle speed calculation means, and the recommended vehicle speed is displayed by the recommended vehicle speed display means.

  With this configuration, the recommended vehicle speed display means displays the recommended vehicle speed at which the vehicle can pass the traffic signal during the period when the next traffic light is green (that is, the recommended vehicle speed at which the vehicle can reach the traffic signal when the next traffic signal is green) Therefore, the driver can be encouraged to travel at the recommended vehicle speed, and the driver can operate the accelerator so that the vehicle can travel at the recommended vehicle speed. Can pass through. As a result, it is possible to increase the number of opportunities for the vehicle to pass the next traffic light with a green signal without stopping at the next traffic light. And the number of vehicle starts (acceleration) can be reduced, and the fuel consumption of the internal combustion engine can be improved.

  Further, as in claim 2, the vehicle speed control means controls the vehicle speed based on the travel distance to the next traffic light and the traffic light change timing information so that the vehicle can pass through the traffic light during the period when the next traffic light is green. You may do it. In this way, even if the driver does not operate the accelerator, the vehicle speed is automatically controlled by the vehicle speed control means so that the vehicle can reliably pass the next traffic light with a green light without stopping at the next traffic light. Thus, the fuel efficiency improvement effect can be obtained with certainty.

  In this case, as in claim 3, based on the travel distance to the next traffic light and the traffic light change timing information, the recommended vehicle speed at which the vehicle can pass the traffic signal during the period when the next traffic light is green is calculated, It is better to control to the recommended vehicle speed. In this way, it is possible to automatically control the vehicle speed to the recommended vehicle speed so that the vehicle can pass the next traffic light with a green light without stopping at the next traffic light.

  In a system having a cruise control function for controlling the vehicle speed to the target vehicle speed set by the driver, the target vehicle speed for cruise control may be set to the recommended vehicle speed.

  By the way, when the vehicle speed is controlled so that the vehicle can pass the traffic signal during the period when the next traffic light is green, the distance between the vehicle and the preceding vehicle is not shortened too much by the brake operation. However, as in claim 4, there is provided an inter-vehicle distance detecting means for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle, and the vehicle speed is determined based on the inter-vehicle distance between the host vehicle and the preceding vehicle. You may make it correct | amend. In this way, it is possible to control the vehicle speed so as to automatically secure a safe inter-vehicle distance between the host vehicle and the preceding vehicle without the driver performing a brake operation or the like. Can be improved.

  The invention according to claims 1 to 4 described above is not limited to a vehicle using only the internal combustion engine as a power source, but is an electric vehicle using only a hybrid electric vehicle or motor using both the internal combustion engine and the motor as power sources. It can also be applied to automobiles.

  Further, in a vehicle equipped with an internal combustion engine as a power source for the vehicle and equipped with an automatic engine stop control means for stopping fuel injection of the internal combustion engine while the vehicle is stopped, the vehicle travels to the next traffic light. Based on the distance and traffic light change timing information, it is judged by the passage judging means whether or not the vehicle can pass through the traffic signal during the green signal period, and the vehicle passes through the traffic signal during the green signal period. If it is determined that the vehicle is not capable of performing the engine stop control before stopping the vehicle, the fuel injection of the internal combustion engine is stopped before the vehicle stops when the driver's intention to decelerate is detected.

  In other words, if it is determined that the vehicle cannot pass the traffic signal during the period when the next traffic light is green, it is determined that the vehicle needs to be stopped at the next traffic light, and the driver's intention to decelerate (for example, brake operation) When the engine is detected, the engine stop control before stopping the vehicle is executed. Thereby, immediately before the next traffic light, the internal combustion engine can be automatically stopped while the vehicle is decelerating to extend the automatic stop period (idling stop period) of the internal combustion engine, and the fuel efficiency improvement effect can be increased.

  The engine stop control before stopping the vehicle always permits the engine stop control before stopping the vehicle when it is determined that the vehicle cannot pass through the traffic signal during the period when the next traffic light is green. However, as described in claim 6, there is provided an operation mode selection means for switching between an operation mode in which the engine stop control before the vehicle is stopped and an operation mode in which the vehicle stop is not performed at the intention of the driver. It may be possible to arbitrarily select whether or not to execute the pre-stop engine stop control. In this way, the engine stop control before the vehicle stop can be executed only when the driver selects the operation mode for performing the engine stop control before the vehicle stop. Therefore, the engine stop before the vehicle stop without giving the driver a sense of incongruity. Control can be performed.

  Several embodiments embodying the best mode for carrying out the present invention will be described below.

A first embodiment of the present invention will be described with reference to FIGS.
First, a schematic configuration of the entire vehicle control system will be described with reference to FIG.
An engine 11 that is an internal combustion engine is mounted as a power source of the vehicle, and the output of the engine 11 is transmitted to the drive wheels of the vehicle via an automatic transmission or the like.

  In addition, the vehicle is provided with an accelerator sensor 12 that detects an accelerator opening (amount of operation of an accelerator pedal), a brake switch 13 that detects a brake operation, and a vehicle speed sensor 14 that detects a vehicle speed. A navigation system 15 for setting a guide route is provided. The navigation system 15 sets a guide route from the current location to the destination based on the road map information stored in the memory when the driver sets the destination.

  Furthermore, a recommended vehicle speed display unit 16 (recommended vehicle speed display means) for displaying a recommended vehicle speed, which will be described later, is provided on the instrument panel of the driver's seat of the vehicle. The display of the navigation system 15 may be used as recommended vehicle speed display means.

  Outputs from the various sensors and switches described above are input to a control circuit (hereinafter referred to as “ECU”) 17. The ECU 17 is mainly composed of a microcomputer, and executes various engine control programs stored in a built-in ROM (storage medium), so that the fuel injection of the fuel injection valve of the engine 11 according to the engine operating state. Control the amount and ignition timing of the spark plug.

  In addition, the ECU 17 executes a recommended vehicle speed setting routine shown in FIGS. 3 and 4 to be described later, and is installed in the planned travel route from the current location of the vehicle based on the road map information and the vehicle position information acquired from the navigation system 15. It functions as a traffic light distance information calculation means for calculating the travel distance to the next traffic light, and receives traffic light management information from an external system such as a traffic light management system. Based on this traffic light management information, the green signal of the next traffic light It functions as a traffic light change time information acquisition means for obtaining a start time and an end time of a green light (hereinafter collectively referred to as “traffic light change time information”).

  Note that the method for obtaining the traffic light change time information (the start time of the green light and the end time of the green light) may be changed as appropriate. For example, when the traffic light management information can be fetched from the navigation system 15, the navigation system 15 The traffic signal change time information may be obtained based on the traffic signal management information fetched from.

  Alternatively, every time the vehicle travels in the vicinity of a traffic light, the traffic light is imaged by a camera mounted on the vehicle, and the display color, imaging date and time, traffic light position, etc. of the traffic light at that time are stored in a memory, and the traffic light for each traffic light. An information database may be created, and signal change timing information may be obtained based on the signal information database.

  Further, the ECU 17 recommends the recommended vehicle speed (the vehicle can pass through the traffic signal during the period when the next traffic light is green based on the travel distance to the next traffic light and the traffic light change timing information (green signal start timing and green signal end timing). That is, it functions as a recommended vehicle speed calculating means for calculating a recommended vehicle speed at which the vehicle can reach the traffic signal during a period when the traffic light is green, and this recommended vehicle speed is displayed on the recommended vehicle speed display unit 16.

Here, a method for calculating the recommended vehicle speed will be described with reference to FIG.
As shown in FIG. 2 (a), when the current display of the next traffic light is a green signal, the current time t0 and the time t1 when the display of the next traffic light changes from a green light to a yellow signal (end time of the green light). Based on this, the time .DELTA.T1 from the present until the next traffic light display changes to a yellow signal is calculated.

After this, it is recommended that the vehicle can pass through the traffic light during the period when the next traffic light display is green, using the time ΔT1 from the present until the next traffic light changes to a yellow light and the travel distance ΔL1 to the next traffic light. The lower limit vehicle speed V1 is calculated from the following equation.
V1 = ΔL1 / ΔT1

If this recommended lower limit vehicle speed V1 is less than or equal to the legal maximum speed Vmax of the current traveling road, the recommended lower limit vehicle speed V1 is set as the final recommended vehicle speed Vt as it is.
Vt = V1

  When the recommended lower limit vehicle speed V1 is equal to or lower than the legal maximum speed Vmax, the vehicle speed within the range from the recommended lower limit vehicle speed V1 to the legal maximum speed Vmax may be set as the final recommended vehicle speed Vt.

On the other hand, when the recommended lower limit vehicle speed V1 is higher than the legal maximum speed Vmax, the legal maximum speed Vmax is set as the final recommended vehicle speed Vt.
Vt = Vmax

  On the other hand, as shown in FIG. 2 (b), when the current display of the next traffic light is not a blue signal (a yellow signal or a red signal), the current time t0 and the display of the next traffic light are changed from a red signal to a blue signal. On the basis of the time t2 (the start time of the green signal) at which the time is changed, a time ΔT2 from the present until the display of the next traffic light changes to the green signal is calculated. Further, based on the current time t0 and the time t3 when the next traffic signal display changes from the green signal to the yellow signal), the time ΔT3 from the present time until the next traffic signal display changes to the yellow signal is calculated.

After this, using the time ΔT2 from the present until the next traffic light changes to a green light and the travel distance ΔL1 to the next traffic light, the recommended upper limit that the vehicle can pass through the traffic light during the period when the next traffic light is green. The vehicle speed V2 is calculated from the following equation.
V2 = ΔL1 / ΔT2

Further, the recommended lower limit at which the vehicle can pass through the traffic light during the period when the next traffic light display is green with the time ΔT3 until the next traffic light display changes to a yellow signal and the travel distance ΔL1 to the next traffic light. The vehicle speed V3 is calculated from the following formula.
V3 = ΔL1 / ΔT3

Thereafter, an intermediate value V (for example, an average value) between the recommended upper limit vehicle speed V2 and the recommended lower limit vehicle speed V3 is calculated from the following equation, and is set as the recommended intermediate vehicle speed V.
V = (V2 + V3) / 2

When the recommended intermediate vehicle speed V is equal to or lower than the legal maximum speed Vmax, the recommended intermediate vehicle speed V is set as the final recommended vehicle speed Vt as it is.
Vt = V

  When the recommended intermediate vehicle speed V is less than the legal maximum speed Vmax, the vehicle speed within the range from the recommended intermediate vehicle speed V to the legal maximum speed Vmax is set as the final recommended vehicle speed Vt within the range not exceeding the recommended upper limit vehicle speed V2. You may make it do.

On the other hand, when the recommended intermediate vehicle speed V is higher than the legal maximum speed Vmax, the legal maximum speed Vmax is set as the final recommended vehicle speed Vt.
Vt = Vmax
The setting of the recommended vehicle speed Vt described above may be executed when the travel distance from the current location of the vehicle to the next traffic light becomes a predetermined distance or less.

Hereinafter, the processing content of the recommended vehicle speed setting routine of FIGS. 3 and 4 executed by the ECU 17 will be described.
The recommended vehicle speed setting routine shown in FIGS. 3 and 4 is executed at a predetermined cycle while the ECU 17 is powered on. When this routine is started, first, in step 101, the current display of the next traffic light installed on the planned travel route of the vehicle based on traffic light management information taken from an external system such as a traffic light management system is a green signal. It is determined whether or not there is.

  If it is determined in step 101 that the current display of the next traffic light is a green signal, the process proceeds to step 102, and the time t1 when the display of the next traffic light changes from a green signal to a yellow signal based on the traffic light management information and the like. After calculating (the end time of the green light), the process proceeds to step 103, and the display of the next traffic light changes from the present to the yellow light based on the current time t0 and the time t1 when the display of the next traffic light changes from the green light to the yellow signal. Time ΔT1 is calculated.

Thereafter, the process proceeds to step 104, and the travel distance ΔL1 from the current location to the next traffic light is calculated based on the road map information and the vehicle position information acquired from the navigation system 15. Then, the process proceeds to step 105, where Using the time ΔT1 until the display changes to a yellow signal and the travel distance ΔL1 to the next traffic light, the recommended lower limit vehicle speed V1 at which the vehicle can pass the traffic signal during the period when the next traffic light is green is calculated by the following equation. .
V1 = ΔL1 / ΔT1

  Thereafter, the routine proceeds to step 106, where it is determined whether or not the recommended lower limit vehicle speed V1 is less than or equal to the legal maximum speed Vmax of the current traveling road. Information on the statutory maximum speed Vmax may be acquired from a database of the navigation system 15 or an external traffic management system.

If it is determined in step 106 that the recommended lower limit vehicle speed V1 is less than or equal to the legal maximum speed Vmax, the routine proceeds to step 107, where the recommended lower limit vehicle speed V1 is set as the final recommended vehicle speed Vt as it is.
Vt = V1

On the other hand, if it is determined in step 106 that the recommended lower limit vehicle speed V1 is higher than the legal maximum speed Vmax, the routine proceeds to step 108, where the legal maximum speed Vmax is set as the final recommended vehicle speed Vt.
Vt = Vmax

  On the other hand, if it is determined in step 101 that the current display of the next traffic light is not a green signal (yellow signal or red signal), the process proceeds to step 109 in FIG. After calculating the time t2 when the display of the next traffic light changes from the red signal to the blue signal (the start time of the green signal), the process proceeds to step 110, at the current time t0 and the time t2 when the display of the next traffic light changes from the red signal to the green signal. Based on this, the time .DELTA.T2 from the present until the next traffic light display changes to a green signal is calculated.

  Thereafter, the process proceeds to step 111, and after calculating the time t3 (the end time of the green signal) when the display of the next traffic signal changes from the green signal to the yellow signal based on the traffic signal management information, the process proceeds to step 112, and the current time t0 and the next Based on the time t3 when the display of the next traffic light changes from the green signal to the yellow signal, the time ΔT3 from the present until the display of the next traffic light changes to the yellow signal is calculated.

Thereafter, the process proceeds to step 113, and the travel distance ΔL1 from the current position to the next traffic light is calculated based on the road map information and the vehicle position information. Then, the process proceeds to step 114, and the display of the next traffic light changes from the present to the green light. The recommended upper limit vehicle speed V2 at which the vehicle can pass the traffic signal during the period when the display of the next traffic signal is green is calculated using the following equation using the time ΔT2 and the travel distance ΔL1 to the next traffic light.
V2 = ΔL1 / ΔT2

After this, the routine proceeds to step 115, where the vehicle uses the time ΔT3 until the next traffic light display changes to a yellow signal and the travel distance ΔL1 to the next traffic light during the period when the next traffic light display is green. The recommended lower limit vehicle speed V3 that can pass through the traffic light is calculated from
V3 = ΔL1 / ΔT3

Thereafter, the routine proceeds to step 116, where an intermediate value V (for example, an average value) between the recommended upper limit vehicle speed V2 and the recommended lower limit vehicle speed V3 is calculated by the following equation, and is set as the recommended intermediate vehicle speed V.
V = (V2 + V3) / 2
Thereafter, the routine proceeds to step 117, where it is determined whether or not the recommended intermediate vehicle speed V is equal to or lower than the legal maximum speed Vmax.

If it is determined in step 117 that the recommended intermediate vehicle speed V is less than or equal to the legal maximum speed Vmax, the process proceeds to step 118, where the recommended intermediate vehicle speed V is set as the final recommended vehicle speed Vt as it is.
Vt = V

On the other hand, if it is determined in step 117 that the recommended intermediate vehicle speed V is higher than the legal maximum speed Vmax, the routine proceeds to step 119, where the legal maximum speed Vmax is set as the final recommended vehicle speed Vt.
Vt = Vmax
After the recommended vehicle speed Vt is set as described above, the process proceeds to step 120 in FIG. 3 and the recommended vehicle speed Vt is displayed on the recommended vehicle speed display unit 16.

  In the first embodiment described above, the recommended vehicle speed Vt at which the vehicle can pass the next traffic light with a green signal within a range not exceeding the legal maximum speed Vmax is calculated, and this recommended vehicle speed Vt is displayed at 15 when the recommended vehicle speed is displayed. Therefore, the driver can be urged to travel at the recommended vehicle speed Vt, and the driver can operate the accelerator so that the vehicle can travel at the recommended vehicle speed Vt. Can pass through. As a result, it is possible to increase the number of opportunities for the vehicle to pass through the traffic light with a green light without stopping at the traffic light, thereby reducing the number of stops of the vehicle due to the red light of the traffic light and reducing braking that causes fuel consumption deterioration. In addition, the number of vehicle starts (the number of accelerations) can be reduced, and the fuel consumption of the engine 11 can be improved.

Next, Embodiment 2 of the present invention will be described with reference to FIG.
In the second embodiment, a laser radar sensor (not shown) is attached to the vehicle as inter-vehicle distance detection means for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle. Instead of the laser radar sensor, an inter-vehicle distance detection means for detecting the inter-vehicle distance using radio waves or sound waves may be attached. Other system configurations are substantially the same as those of the first embodiment.

  In the second embodiment, the ECU 17 executes the vehicle speed control routine of FIG. 5 to calculate a recommended vehicle speed at which the vehicle can pass the traffic signal during the period when the next traffic light is green, and the vehicle speed detected by the vehicle speed sensor 14 is calculated. It functions as vehicle speed control means for controlling the engine output, the gear ratio of the automatic transmission, and the like so as to match the recommended vehicle speed. Accordingly, the ECU 17 automatically controls the vehicle speed to the recommended vehicle speed so that the vehicle can pass through the traffic light with a green light without stopping at the next traffic light.

At that time, the ECU 17 corrects the vehicle speed when the inter-vehicle distance detected by the laser radar sensor and the preceding vehicle is equal to or less than a predetermined value, and automatically provides a safe inter-vehicle distance between the own vehicle and the preceding vehicle. The vehicle speed is controlled to ensure the distance.
Note that the vehicle speed control of the second embodiment may be permitted when the travel distance from the current location of the vehicle to the next traffic light becomes a predetermined value or less.

  The vehicle speed control routine shown in FIG. 5 is executed at a predetermined cycle while the ECU 17 is powered on. When this routine is started, first, in step 201, the recommended vehicle speed setting routine of FIG. 3 and FIG. 4 described above is executed, and the vehicle passes the next traffic light with a blue signal within a range not exceeding the legal maximum speed Vmax. The recommended recommended vehicle speed Vt is calculated. In the second embodiment, the recommended vehicle speed Vt may be displayed on the recommended vehicle speed display unit 16, but the recommended vehicle speed display unit 16 may be omitted and the recommended vehicle speed Vt may not be displayed.

  Thereafter, the process proceeds to step 202, and after reading the inter-vehicle distance D between the own vehicle detected by the laser radar sensor and the preceding vehicle, the process proceeds to step 203, where the inter-vehicle distance D between the own vehicle and the preceding vehicle is a predetermined value or more. It is determined whether or not.

If it is determined in step 203 that the inter-vehicle distance D between the host vehicle and the preceding vehicle is greater than or equal to a predetermined value, the process proceeds to step 204, where the recommended vehicle speed Vt is set as the target vehicle speed.
Target vehicle speed = Recommended vehicle speed Vt

  Thereafter, the process proceeds to step 206, and the next traffic light is indicated by a blue signal by controlling the engine output, the gear ratio of the automatic transmission, etc. so that the vehicle speed detected by the vehicle speed sensor 14 matches the target vehicle speed (= recommended vehicle speed Vt). During this period, the vehicle speed is controlled so that the vehicle can pass through the traffic light.

On the other hand, if it is determined in step 203 that the inter-vehicle distance D between the host vehicle and the preceding vehicle is shorter than a predetermined value, the process proceeds to step 205 and the recommended vehicle speed Vt is reduced by a predetermined value α. Set the value as the target vehicle speed.
Target vehicle speed = Recommended vehicle speed Vt -α
Here, the predetermined value α may be a preset fixed value, but may be set according to the inter-vehicle distance D, the decreasing speed of the inter-vehicle distance D, or the like.

  Thereafter, the process proceeds to step 206, where the vehicle speed is reduced by controlling the engine output, the gear ratio of the automatic transmission, and the like so that the vehicle speed detected by the vehicle speed sensor 14 matches the target vehicle speed (= recommended vehicle speed Vt−α). It correct | amends so that the distance D between vehicles may become more than predetermined value.

  In the second embodiment described above, the vehicle speed is controlled so that the next traffic signal can pass the traffic signal during the period of the green signal by controlling the vehicle speed to the target vehicle speed (= recommended vehicle speed Vt) by the ECU 17. Therefore, even if the driver does not operate the accelerator, the ECU 17 can automatically control the vehicle speed so that the vehicle can pass through the traffic light with a green light without stopping at the traffic light. As a result, it is possible to increase the number of opportunities for the vehicle to pass through the traffic light with a green light without stopping at the traffic light, thereby reducing the number of stops of the vehicle due to the red light of the traffic light and reducing braking that causes fuel consumption deterioration. In addition, the number of vehicle starts (the number of accelerations) can be reduced, and the fuel consumption of the engine 11 can be improved.

  In addition, in the second embodiment, since the vehicle speed is corrected for deceleration when the inter-vehicle distance between the host vehicle and the preceding vehicle is equal to or less than a predetermined value, the driver automatically performs the operation without the brake operation or the like. The vehicle speed can be controlled so as to ensure a safe inter-vehicle distance between the vehicle and the preceding vehicle, and safety can be improved.

  In the second embodiment, there is a method for controlling the vehicle speed so that the vehicle can pass the traffic signal during the period when the next traffic light is green, and a method for correcting the vehicle speed based on the distance between the host vehicle and the preceding vehicle. You may change suitably. For example, in a system having a cruise control function for controlling the vehicle speed to the target vehicle speed set by the driver, the target vehicle speed for cruise control may be set to the recommended vehicle speed Vt.

  In addition, the function of correcting the vehicle speed based on the inter-vehicle distance between the host vehicle and the preceding vehicle is omitted, and the driver increases the inter-vehicle distance by a brake operation or the like so that the inter-vehicle distance between the host vehicle and the preceding vehicle does not become too short. You may make it adjust.

Next, Embodiment 3 of the present invention will be described with reference to FIG.
In the third embodiment, the ECU 17 executes an engine automatic stop / start control routine (not shown) to stop fuel injection of the engine 11 when the driver stops the vehicle and a predetermined automatic stop condition is satisfied. Functioning as an automatic engine stop control means for automatically stopping the engine 11, and then the engine 11 is automatically operated when a predetermined automatic start condition is satisfied by performing an operation of the driver to start the vehicle. I'm trying to restart it.

Further, the ECU 17 executes the engine stop control routine before stopping the vehicle shown in FIG. 6 to calculate a recommended lower limit vehicle speed at which the vehicle can pass the traffic signal during the period when the next traffic light is green. If the next traffic light determines whether the vehicle can pass the traffic light during the green light period compared to the speed, and if the next traffic light determines that the vehicle cannot pass the traffic light during the green light period, It is determined that it is necessary to stop the vehicle with this signal, and when the driver's intention to decelerate (for example, brake operation) is detected, engine stop control before stopping the vehicle is executed to stop fuel injection of the engine 11 before stopping the vehicle. Like to do.
The engine stop control before stopping the vehicle according to the third embodiment may be permitted when the travel distance from the current location of the vehicle to the next traffic light becomes a predetermined value or less.

  The engine stop control routine before the vehicle stop shown in FIG. 6 is executed at a predetermined cycle while the ECU 17 is powered on. When this routine is started, first, at step 301, the recommended vehicle speed setting routine of FIG. 3 and FIG. 4 described above is executed, and the recommended lower limit vehicle speed V1 at which the vehicle can pass the traffic signal during the period when the next traffic light is green. Alternatively, V3 is calculated and the recommended vehicle speed Vt is set within a range not exceeding the legal maximum speed Vmax. In the third embodiment, the recommended vehicle speed Vt may be displayed on the recommended vehicle speed display unit 16, but the recommended vehicle speed display unit 16 may be omitted and the recommended vehicle speed Vt may not be displayed.

  Thereafter, the process proceeds to step 302, where it is determined whether or not the fuel-saving driving mode is selected by operating the driving mode selection switch (driving mode selection means) of the driver, and it is determined that the fuel-saving driving mode is not selected. If it is, the routine is terminated without executing the processing related to the engine stop control before stopping the vehicle after step 303, and the engine stop control before stopping the vehicle is prohibited.

  On the other hand, if it is determined in step 302 that the fuel-saving driving mode is selected, the engine stop control before vehicle stop is permitted, and the processing related to the engine stop control before vehicle stop after step 303 is performed as follows. To do so. First, at step 303, it is determined whether or not the vehicle can pass through the traffic light during the period when the next traffic light is green, depending on whether the recommended lower limit vehicle speed V1 or V3 is higher than the legal maximum speed Vmax.

  If it is determined in step 303 that the recommended lower limit vehicle speed V1 or V3 is higher than the legal maximum speed Vmax, and it is determined that the vehicle cannot pass the traffic signal during the period when the next traffic light is green, the next traffic light In step 304, it is determined that it is necessary to stop the vehicle. Based on the output signal from the brake switch 13, it is determined whether or not a brake operation has been performed. Note that it may be determined whether or not the driver intends to decelerate by determining whether or not the accelerator operation amount = 0 state has continued for a predetermined period or longer based on the output signal of the accelerator sensor 12.

  In this step 304, when it is determined that the brake is operated and the driver's intention to decelerate is detected, the process proceeds to step 305, where the fuel injection of the engine 11 is stopped and the engine 11 is stopped before stopping the vehicle. Execute stop control.

  In the third embodiment described above, when it is determined that the vehicle cannot pass the traffic signal during the period when the next traffic light is green, it is determined that the vehicle needs to be stopped at the next traffic light, and the driver's Since engine stop control before stopping the vehicle that stops fuel injection of the engine 11 before stopping the vehicle when the intention to decelerate (for example, brake operation) is detected, the engine 11 is automatically stopped while the vehicle is decelerating. The automatic stop period (idling stop period) of the engine 11 can be extended, and the fuel consumption of the engine 11 can be improved.

  Moreover, in the third embodiment, the engine stop control before stopping the vehicle is permitted only when the fuel-saving driving mode is selected by the driver, so the engine stop control before stopping the vehicle without giving the driver a sense of incongruity. Can be executed.

  In the third embodiment, the engine stop control before stopping the vehicle is always permitted when it is determined that the vehicle cannot pass the traffic signal during the period when the traffic light is green, and the driver's intention to decelerate is detected. good. Moreover, you may change suitably the method of determining whether a vehicle can pass this traffic signal in the period when the next traffic signal is a green light.

  In the first to third embodiments, the recommended vehicle speed is calculated based on the travel distance to the next traffic light and the traffic light change timing information (the green signal start time and the green signal end time). When the traffic lights are installed at relatively short intervals, the recommended vehicle speed may be calculated based on the travel distance to each traffic light and the traffic light change timing information of each traffic light.

  Further, the technique of the first embodiment (recommended vehicle speed display control for displaying the recommended vehicle speed), the technique of the second embodiment (vehicle speed control for controlling the vehicle speed to the recommended vehicle speed), and the technique of the third embodiment (before the vehicle stops). The engine stop control) is not limited to a vehicle that uses only the engine 11 as a power source, but can also be applied to a hybrid electric vehicle that uses both an engine and a motor as power sources.

Furthermore, the technique of the first embodiment and the technique of the second embodiment can be applied to an electric vehicle using only a motor as a power source.
Moreover, you may make it implement combining the technique of the said Example 1, the technique of the said Example 2, and the technique of the said Example 3 in combination.

It is a block diagram which shows schematic structure of the vehicle control system in Example 1 of this invention. It is a figure for demonstrating the calculation method of a recommended vehicle speed. 6 is a flowchart (part 1) illustrating a flow of processing of a recommended vehicle speed setting routine according to the first embodiment. 7 is a flowchart (No. 2) for explaining the flow of processing of a recommended vehicle speed setting routine according to the first embodiment. 6 is a flowchart for explaining a flow of processing of a vehicle speed control routine according to a second embodiment. 12 is a flowchart for explaining a processing flow of an engine stop control routine before a vehicle stop according to a third embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Engine (internal combustion engine), 12 ... Accelerator sensor, 13 ... Brake switch, 14 ... Vehicle speed sensor, 15 ... Navigation system, 16 ... Recommended vehicle speed display part (recommended vehicle speed display means), 17 ... ECU (signal machine distance information calculation means) , Signal change timing information acquisition means, recommended vehicle speed calculation means, vehicle speed control means, engine automatic stop control means)

Claims (6)

Traffic light distance information calculating means for calculating a travel distance from the current location of the vehicle to the next traffic light installed in the planned travel route;
A traffic light change timing information acquisition means for acquiring a start timing and / or an end timing of a green traffic light (hereinafter collectively referred to as “signal change timing information”);
A recommended vehicle speed calculating means for calculating a recommended vehicle speed at which the vehicle can pass the traffic signal during a period when the next traffic signal is green based on a travel distance to the next traffic signal and the traffic signal change timing information; and displaying the recommended vehicle speed And a recommended vehicle speed display means. Traffic light distance information calculating means for calculating a travel distance from the current location of the vehicle to the next traffic light installed in the planned travel route;
A traffic light change timing information acquisition means for acquiring a start timing and / or an end timing of the green traffic light (hereinafter collectively referred to as “signal change timing information”);
Vehicle speed control means for controlling the vehicle speed based on the travel distance to the next traffic light and the traffic light change timing information so that the vehicle can pass through the traffic light during a period when the next traffic light is green. A vehicle control device characterized by the above.   The vehicle speed control means calculates a recommended vehicle speed at which the vehicle can pass through the traffic light during a period when the next traffic light is green based on the travel distance to the next traffic light and the traffic light change timing information, and the vehicle speed is recommended. The vehicle control device according to claim 2, wherein the vehicle control device controls the vehicle speed. An inter-vehicle distance detecting means for detecting the inter-vehicle distance between the host vehicle and the preceding vehicle;
The vehicle control device according to claim 2 or 3, wherein the vehicle speed control means corrects the vehicle speed based on an inter-vehicle distance between the host vehicle and a preceding vehicle detected by the inter-vehicle distance detection means. In a vehicle control apparatus equipped with an internal combustion engine as a power source of a vehicle and provided with an automatic engine stop control means for stopping fuel injection of the internal combustion engine while the vehicle is stopped,
Traffic light distance information calculating means for calculating a travel distance from the current location of the vehicle to the next traffic light installed in the planned travel route;
A traffic light change timing information acquisition means for acquiring a start timing and / or an end timing of a green traffic light (hereinafter collectively referred to as “signal change timing information”);
Passage determining means for determining whether or not the vehicle can pass through the traffic signal during a period of a green light on the basis of the travel distance to the next traffic signal and the traffic light change timing information; When the passage determining means determines that the vehicle cannot pass through the traffic light during the green signal period of the next traffic light, the stop control means detects the driver's intention to decelerate the internal combustion engine from before the vehicle stops. A vehicle control device that performs engine stop control before stopping the vehicle to stop fuel injection.   6. The vehicle control device according to claim 5, further comprising operation mode selection means for switching between an operation mode in which the engine stop control before the vehicle is stopped and an operation mode in which the engine stop control is not performed at the driver's intention. .

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