JP2018178885A - Control device of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a vehicle which can perform vehicle-traveling S&S control capable of suppressing a restart of an engine during a stop of the vehicle in vehicle-stop S&S control.SOLUTION: In the case that a vehicle-traveling automatic stop time rate is lower than a prescribed first threshold, and a total automatic stop time rate is lower than a prescribed second threshold when a vehicle-traveling automatic stop condition is established (YES determination in ST4), coasting traveling is performed (ST5). That is, when a battery discharge amount in traveling is small, and also a total battery discharge amount is small, it is determined that an engine stop continuation time by vehicle-stop S&S control can be secured long when a vehicle is stopped thereafter, and coasting traveling for automatically stopping the engine is performed. By this constitution, a possibility that the engine is restarted in a stop state of the vehicle becomes low, a fuel consumption rate can be also improved, and it can be avoided that an occupant feels an incongruity resulting from a sound and vibration.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a control device of a vehicle. In particular, the present invention relates to a control device applied to a vehicle capable of automatically stopping an internal combustion engine when a predetermined automatic stop condition is satisfied during traveling and stopping of the vehicle.

  Conventionally, in order to improve the fuel consumption rate of an internal combustion engine (engine), the engine is automatically stopped when a predetermined automatic stop condition is satisfied, and the predetermined automatic stop cancellation condition is satisfied during the automatic engine stop. So-called stop-and-start control (hereinafter referred to as S & S control) is performed to automatically restart the engine.

  As this S & S control, the engine and the driving wheel when the accelerator off operation or the like is performed while the vehicle is traveling, in addition to the S & S control during stop (automatic stop control during stop) which automatically stops the engine while the vehicle is stopped. S & S control (automatic stop control during travel) is known during travel, in which inertial transmission (also called coasting travel) is performed by interrupting power transmission between them and automatically stopping the engine.

  Further, according to Patent Document 1, when the voltage of the battery (storage battery) is equal to or higher than the first voltage threshold, S & S control is permitted while the vehicle is stopped (the engine is automatically stopped when the automatic stop condition is satisfied). Permitting the S & S control during traveling when the voltage of the battery is equal to or higher than a second voltage threshold larger than the first voltage threshold (automatically stopping the engine when the automatic stop condition is satisfied during traveling) Is disclosed.

Patent No. 5382224 gazette

  However, in the vehicles that can perform S & S control while stopping and traveling as described above, the time during which the engine is automatically stopped in traveling S & S control takes into consideration the influence on S & S control while stopping, No specific method has been proposed for determining whether or not S & S control is being performed while traveling (whether or not to stop the engine automatically while traveling).

  For this reason, when the vehicle stops from the traveling state, if the time during which the engine is automatically stopped by the S & S control during traveling is relatively long during the traveling, the battery by the operation of the accessories during that time The amount of discharge of the battery is increased, and the amount of stored power in the battery decreases during a subsequent stop, and power for accessory operation is secured before the vehicle starts moving (before the driver makes a request to start moving) In order to do so, the engine may have been restarted. In such a situation, the engine is operated while the vehicle is at a standstill, leading to deterioration of the fuel consumption rate, and noise or vibration associated with the operation of the engine may cause discomfort to the occupants. There is.

  The present invention has been made in view of such a point, and an object of the present invention is to provide a vehicle capable of S & S control during traveling which can suppress restart of the engine while the vehicle is stopped in stop S & S control. It is in providing a control device.

  The solution means of the present invention for achieving the above object is an automatic stop control during traveling which automatically stops the internal combustion engine when a predetermined automatic stop condition is established while the vehicle is traveling, A control device applied to a vehicle capable of performing automatic stop control during stop while automatically stopping the internal combustion engine when the automatic stop condition is satisfied during stop is assumed. Then, the control device of the vehicle calculates an automatic stop time ratio during traveling, which is a ratio of the automatic stop time of the internal combustion engine during traveling of the vehicle to the ignition ON continuous time in one trip. A total automatic stop time rate calculating unit for calculating a total automatic stop time rate which is a ratio of the total stop time of the internal combustion engine to the total ignition ON time after the storage battery is mounted, and the automatic stop during running of the vehicle When the automatic stop time rate during traveling is less than a predetermined first threshold and the total automatic stop time rate is less than a predetermined second threshold when the condition is satisfied, the vehicle during travel is underway And an automatic stop control unit for automatically stopping the internal combustion engine.

  According to this specific matter, during tripping, the automatic stop time rate calculation unit during traveling sets the ratio of automatic stop time during traveling as the ratio of the automatic stop time of the internal combustion engine during vehicle travel to the ignition ON continuation time in the trip. It is calculated. In addition, after installation of the storage battery (including both the case where the storage battery is installed first and the case where the storage battery is replaced for a new car), the total automatic stop time rate calculation unit calculates the total internal combustion for the total ignition ON time thereafter The total automatic stop time rate is calculated as the ratio of the automatic stop time of the engine.

  And, when the automatic stop condition during traveling is satisfied during traveling of the vehicle, the automatic stop time ratio during traveling is less than the first predetermined threshold and the total automatic stop time ratio is less than the second predetermined threshold Automatically stop the internal combustion engine while the vehicle is traveling. That is, when the automatic stop time rate during traveling is less than the first predetermined threshold, the amount of discharge of the storage battery during traveling is small, and even if the vehicle is stopped thereafter, the stop duration time of the internal combustion engine by the automatic stop control during stoppage is long It can be determined that it can be secured. Similarly, even when the total automatic stop time rate is less than the predetermined second threshold, the discharge amount of the storage battery is small, and even if the vehicle is stopped thereafter, the stop duration time of the internal combustion engine by the automatic stop control during stop can be secured long. It can be judged that it is a state. Therefore, when both of these conditions are met, the internal combustion engine is automatically stopped to allow discharge of the storage battery during traveling. In other words, while the above condition (condition of each automatic stop time rate) is satisfied, the internal combustion engine is automatically stopped in response to the automatic stop condition being satisfied during traveling. As a result, there is a high possibility that the storage capacity of the storage battery is still sufficiently secured at the time of the subsequent stop, and a long duration of stop of the internal combustion engine by the automatic stop control during the stop can be secured. As a result, the possibility that the internal combustion engine will be restarted while the vehicle is stopped is reduced, and the fuel consumption rate can be improved. In addition, it is possible to suppress the discomfort of the occupant due to the sound or vibration accompanying the restart of the internal combustion engine.

  In the present invention, the automatic stop time ratio during traveling (the ratio of the automatic stop time of the internal combustion engine during vehicle travel to the ignition ON continuation time in one trip) is predetermined when the automatic stop condition during travel is satisfied during vehicle travel. If the ratio is less than the first threshold and the total automatic stop time ratio (the ratio of the total stop time of the internal combustion engine to the total ignition ON time after the storage of the storage battery) is less than a predetermined second threshold, The internal combustion engine is automatically stopped while the vehicle is traveling. That is, when there is a high possibility that the storage capacity of the storage battery is sufficiently secured at the time of stopping thereafter, the internal combustion engine is automatically stopped while the vehicle is traveling. As a result, it is possible to secure a long stop duration time of the internal combustion engine by the automatic stop control during the stop (the possibility that the internal combustion engine is restarted in the stop state of the vehicle becomes low), and the fuel consumption rate can be improved. In addition, it is possible to suppress the discomfort of the occupant due to the sound or vibration accompanying the restart of the internal combustion engine.

It is a figure showing a schematic structure of a drive system of a vehicle concerning an embodiment. It is a block diagram showing composition of a control system of vehicles. It is a figure which shows the flow of a process of the information in embodiment. It is a flowchart figure for demonstrating the procedure of S & S control. It is a figure which shows an example of the map for judging the prohibition and permission of automatic stop of an engine according to the automatic stop time rate during driving | running | working. It is a figure which shows an example of the map for judging the prohibition and permission of automatic stop of an engine according to a total automatic stop time rate.

  Hereinafter, embodiments of the present invention will be described based on the drawings.

-Vehicle-
First, a vehicle 100 according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 1, the vehicle 100 includes an engine (internal combustion engine) 1, a transmission (for example, a multistage automatic transmission) 2, a differential device 3, drive wheels (front wheels) 4, 4 and an ECU ( Electronic Control Unit 5). The vehicle 100 is, for example, an FF (front engine and front drive) type, and the output of the engine 1 is transmitted to the differential device 3 through the transmission 2 and distributed to the left and right drive wheels 4 and 4. ing.

  The engine 1 is a driving power source for traveling, and is, for example, a multi-cylinder gasoline engine. The engine 1 is configured to be able to control the operating state by the throttle opening degree (the amount of intake air) of the throttle valve, the fuel injection amount, the ignition timing and the like.

  The transmission 2 is provided in the power transmission path between the engine 1 and the drive wheels 4 and 4 and is configured to shift the rotation of the input shaft and output it to the output shaft. In the transmission 2, an input shaft is connected to the engine 1 (for example, connected via a torque converter), and an output shaft is connected to the drive wheels 4, 4 via a differential device 3 or the like. The transmission 2 also includes a plurality of clutches and brakes, which are friction engagement elements for selectively switching the shift speeds. FIG. 1 shows only the clutch (input clutch) 21 provided on the input shaft receiving the power from the engine 1 among these frictional engagement elements. The engine 1 and the drive wheels 4, 4 are selectively connected via the transmission 2 by the clutch 21. Specifically, when the clutch 21 is engaged, power transmission between the engine 1 and the drive wheels 4 and 4 is enabled (by selectively engaging the other clutches and the brakes). Power transmission is enabled when a predetermined gear is established), and power transmission between the engine 1 and the drive wheels 4 and 4 is interrupted when the clutch 21 is released. .

-ECU-
The ECU 5 is configured to perform operation control of the engine 1, shift control of the transmission 2, and the like. Specifically, as shown in FIG. 2, the ECU 5 includes a CPU 51, a ROM 52, a RAM 53, a backup RAM 54, an input interface 55, and an output interface 56. The ECU 5 is an example of the “control device” in the present invention.

  The CPU 51 executes arithmetic processing based on various control programs and maps stored in the ROM 52. The ROM 52 stores various control programs, maps referred to when the various control programs are executed, and the like. The RAM 53 is a memory for temporarily storing the calculation result by the CPU 51, the detection result of each sensor, and the like. The backup RAM 54 is a non-volatile memory for storing data to be stored when the ignition is turned off.

  Connected to the input interface 55 are a crank position sensor 61, an accelerator opening sensor 62, a throttle opening sensor 63, a vehicle speed sensor 64, a brake pedal sensor 65, a start switch 66, a battery temperature sensor 67 and the like.

  The crank position sensor 61 detects a rotational angle position of a crankshaft (not shown). The accelerator opening sensor 62 detects the amount of depression of the accelerator pedal 62a. The throttle opening degree sensor 63 detects the opening degree of a throttle valve (not shown). The vehicle speed sensor 64 is for calculating the vehicle speed, and detects, for example, the rotational speed of the output shaft of the transmission 2. The brake pedal sensor 65 detects the amount of depression of the brake pedal 65a. The start switch 66 is operated by the driver, and is pushed in at engine start request and engine stop request. Along with this operation, an engine start request signal or an engine stop request signal is output from the start switch 66 to the ECU 5. The battery temperature sensor 67 is provided to detect the battery temperature and estimate the liquid temperature of the battery.

  An injector 71, an igniter 72, a throttle motor 73, an oil pressure control device 74 and the like are connected to the output interface 56. The injector 71 is a fuel injection valve and can adjust the fuel injection amount. The igniter 72 is provided to adjust the ignition timing by the spark plug. The throttle motor 73 is provided to adjust the throttle opening of the throttle valve.

  Then, the ECU 5 is configured to be able to control the operating state of the engine 1 by controlling the throttle opening degree, the fuel injection amount, the ignition timing and the like based on the detection results of the respective sensors and the like. Further, the ECU 5 is configured to be able to execute the shift control of the transmission 2 by controlling the hydraulic control device 74. In addition, the ECU 5 is configured to be able to execute S & S (stop and start) control described later.

-S & S control-
Next, the S & S control will be described. In the vehicle 100 according to the present embodiment, S & S control (automatic stop control during stop) for stopping the engine 1 automatically while the vehicle 100 is stopped, and accelerator off operation etc. while the vehicle 100 is traveling, as S & S control. If it is performed, S & S control (automatic stop control during travel) is possible during travel where coasting travel is performed by interrupting the power transmission between the engine 1 and the drive wheels 4, 4 and automatically stopping the engine 1 It has become. Each of these will be described below.

(Stop S & S control)
When the vehicle 100 is stopped, the engine 1 is automatically stopped when the automatic stop condition (idling stop condition) is satisfied while the vehicle 100 is stopped, and the automatic stop cancellation condition (idle stop cancellation condition) is When it is established, the engine 1 is automatically restarted.

  As the automatic stop condition during stop, for example, the start switch 66 is ON (ignition ON), accelerator OFF (operation amount of the accelerator pedal 62a is zero), and the brake operation amount is equal to or more than a predetermined determination threshold. It is set to include that the vehicle speed is substantially zero. Whether or not the start switch 66 is turned on is determined based on whether or not the engine start request signal is output from the start switch 66, and then the engine stop request signal is output. Whether or not the accelerator is off is determined according to an output signal from the accelerator opening sensor 62. It is determined in accordance with an output signal from the brake pedal sensor 65 whether the brake operation amount is equal to or more than a predetermined determination threshold. Whether or not the vehicle speed is substantially zero is determined according to an output signal from the vehicle speed sensor 64.

  Then, when the automatic stop condition is established while the vehicle is stopped, the ECU 5 outputs a fuel injection stop command to the injector 71 to stop the fuel injection (fuel cut) to automatically stop the engine 1. In addition to fuel cut, ignition cut may be performed.

  On the other hand, as the automatic stop cancellation condition during stopping, the depression of the brake pedal 65a is relaxed in a state where the engine 1 is automatically stopped with the establishment of the automatic stop condition during stopping, and the brake operation amount is a predetermined threshold It is set to include being smaller than. Then, when the automatic stop cancellation condition is satisfied while the engine 1 is automatically stopped, the ECU 5 outputs an engine restart command to the igniter 72, the injector 71 and a starter motor (not shown), and the ignition operation of the ignition plug is performed. The fuel injection from the injectors 71 is started, and the starter motor is operated to crank the engine 1 to automatically restart the engine 1.

(S and S control while driving)
While the vehicle 100 is traveling, the S & S control during traveling releases the clutch 21 by the hydraulic control device 74 and automatically stops the engine 1 when the automatic stop condition (course running execution condition) is satisfied during traveling. When the automatic stop cancellation condition (coasting travel cancellation condition) is satisfied during traveling, the hydraulic control device 74 engages the clutch 21 and automatically restarts the engine 1.

  As the automatic stop condition during traveling, for example, the start switch 66 is on (ignition ON), the accelerator is off, the brake is off (the operation amount of the brake pedal 65a is zero), the vehicle speed is a predetermined value It is set to include the above. As in the case of the automatic stop condition during a stop, whether or not the start switch 66 is turned on indicates whether the engine start request signal is output from the start switch 66 and then the engine stop request signal is output. It is judged according to the person. Whether or not the accelerator is off is determined according to an output signal from the accelerator opening sensor 62. Whether the brake is off or not is determined according to the output signal from the brake pedal sensor 65. Whether or not the vehicle speed is equal to or more than a predetermined value is determined according to an output signal from the vehicle speed sensor 64.

  Then, when the automatic stop condition during traveling is satisfied, the ECU 5 outputs a clutch release command to the hydraulic control device 74 to release the clutch 21. Further, the ECU 5 outputs a fuel injection stop command to the injector 71 to stop the fuel injection (fuel cut), thereby automatically stopping the engine 1. In addition to fuel cut, ignition cut may be performed.

  On the other hand, as the automatic stop cancellation condition during traveling, for example, an accelerator on operation is performed, and a brake on operation is performed in a state where the coasting traveling is performed along with the establishment of the automatic stop condition during traveling. It is set to include the fact that the vehicle speed has dropped below a predetermined value. That is, if any one of these conditions is satisfied, the coasting travel is canceled as the automatic stop cancellation condition is satisfied during traveling. Specifically, when the traveling stop automatic stop cancellation condition is satisfied in the state where the coasting travel is being executed, the ECU 5 outputs a clutch engagement command to the hydraulic control device 74 to engage the clutch 21. In addition, the ECU 5 outputs an engine restart command to the igniter 72, the injector 71 and a starter motor (not shown) to start the ignition operation of the spark plug and fuel injection from the injector 71, and operates the starter motor. The engine 1 is automatically restarted by performing cranking.

(Execution judgment of S & S control while traveling)
In a vehicle that is capable of such S & S control while stopping and S & S control while traveling, S & S while traveling considering the influence that the time when the engine is automatically stopped in S & S control while traveling is on the S & S control while stopping It has not been proposed about a specific method for determining the presence or absence of execution of control (whether or not the engine is automatically stopped while traveling). For this reason, when the vehicle stops from the traveling state, if the time during which the engine is automatically stopped by the S & S control during traveling is relatively long during the traveling, the battery by the operation of the accessories during that time The amount of discharge of the battery is increased, and the amount of stored power in the battery decreases during a subsequent stop, and power for accessory operation is secured before the vehicle starts moving (before the driver makes a request to start moving) In order to do so, the engine may have been restarted. In such a situation, the engine is operated while the vehicle is at a standstill, leading to deterioration of the fuel consumption rate, and noise or vibration associated with the operation of the engine may cause discomfort to the occupants. There is.

  In this embodiment, in view of this point, it is determined whether the execution of the S & S control during traveling can be permitted, taking into consideration the influence that the time when the engine is automatically stopped during the S & S control during traveling gives to the S & S control during parking. Thus, while the vehicle is stopped, the vehicle is prevented from restarting the engine while the vehicle is stopped, thereby performing the vehicle-mounted S & S control.

  Specifically, the ignition ON continuation time in one trip (the present trip) (after the engine start request signal is output from the start switch 66, until the current time elapsed without the engine stop request signal being output from the start switch 66 The automatic stop time ratio during travel, which is the ratio of the automatic stop time of the engine 1 to the vehicle travel time with respect to the time period) is calculated. In addition, the total automatic stop time is the ratio of the total stop time of the engine 1 to the total ignition ON time from after the battery installation (including both when the battery is first installed and when the battery is replaced in a new car) Calculate the time rate. Then, when the automatic stop condition during traveling is satisfied while the vehicle is traveling, the automatic stop time ratio during traveling is less than a predetermined first threshold, and the total automatic stop time ratio is a predetermined second threshold. If it is less than this, the engine 1 is automatically stopped while the vehicle is traveling.

  These operations are executed by the ECU 5. For this reason, in the ECU 5, the functional part for calculating the automatic stop time rate during traveling is the automatic stop time rate during calculation according to the present invention (the automatic stop time of the internal combustion engine during vehicle travel for the ignition ON continuation time in one trip). It is comprised as a driving | running | working automatic stop time rate calculation part which calculates a driving | running | working automatic stop time rate which is a ratio. Further, in the ECU 5, the functional part for calculating the total automatic stop time rate is the ratio of the total automatic stop time rate calculation part according to the present invention (the ratio of the total internal stop time of the internal combustion engine to the total ignition ON time after the storage battery is mounted) A total automatic stop time rate calculating unit is configured to calculate the total automatic stop time rate. Furthermore, in the ECU 5, a function part for automatically stopping the engine 1 while the vehicle is traveling is an automatic stop control unit according to the present invention (the automatic stop time ratio during traveling is predetermined when the automatic stop condition is established while the vehicle is traveling). The automatic stop control unit is configured to automatically stop the internal combustion engine while the vehicle is traveling when the total automatic stop time rate is less than a predetermined second threshold value.

  FIG. 3 is a diagram showing the flow of information processing in the present embodiment.

  First of all, the calculation of the automatic stop time rate during traveling performed by the automatic stop time rate calculation unit during travel is an operation of acquiring 1 trip IG-ON (ignition on) time (process A in FIG. 3), 1 trip during travel Acquisition operation of automatic stop time (battery discharge time during running) (Process B in FIG. 3), and automatic stop during running by dividing the automatic stop time during running of 1 trip by the IG-ON time of 1 trip It is performed by the calculation process (process C in FIG. 3) of the time rate.

  In addition, the calculation of the total automatic stop time rate performed by the total automatic stop time rate calculation unit is an operation of acquiring IG-ON time of all trips (all trips from the time when the battery is new) (Process D in FIG. 3) , Acquisition operation of total automatic stop time (total battery discharge time; sum of automatic stop time of engine 1 in running S & S control and automatic stop time of engine 1 in stopping S & S control) of this total trip (Figure The process E) in 3 and the process of calculating the total automatic stop time rate by dividing the total automatic stop time of all trips by the IG-ON time of all trips (process F in FIG. 3).

  In the present embodiment, the liquid temperature of the battery is used as a parameter for determining the threshold. In other words, the amount of power that can be discharged from the battery differs depending on the liquid temperature of the battery, and the time for which the automatic stop of the engine 1 can continue is also different. A time rate (hereinafter referred to as an automatic stop allowing time rate) for permitting automatic stop of the engine 1 in the S & S control during traveling is determined. As processing for that, acquisition operation of the battery temperature (corresponding to the liquid temperature of the battery) based on the output signal from the battery temperature sensor 67 (processing G in FIG. 3), automatic stop permission time rate according to this battery temperature (battery A calculation process (process H in FIG. 3) of the discharge permission time rate is performed. The relationship between the battery temperature (liquid temperature of the battery) and the automatic stop permission time rate is determined in advance based on experiments and simulations. Note that the SOC (State of Charge) of the battery may be used as a parameter for determining the threshold value, or the SOC and the liquid temperature of the battery may be used in combination.

  And the comparison processing (processing I in FIG. 3) of the automatic stop time rate during traveling obtained in the process C and the automatic stop permission time rate obtained in the process H, and obtained in the process F A comparison process (process J in FIG. 3) of the total automatic stop time rate and the automatic stop permission time rate obtained in the process H is performed, and the automatic stop execution determination operation according to these comparison results (FIG. 3) Process K) is performed. In this automatic stop execution determination operation, when the automatic stop time rate during traveling is less than the automatic stop permission time rate in the comparison process I, the automatic stop time rate during traveling allows the automatic stop of the engine 1. It is determined that the time rate can be Further, in the comparison process J, when the total automatic stop time rate is less than the automatic stop permission time rate, it is determined that the total automatic stop time rate is a time rate at which the automatic stop of the engine 1 can be permitted. . And, when the automatic stop time rate during traveling is less than the automatic stop permission time rate and the total automatic stop time rate is less than the automatic stop permission time rate, the automatic stop time rate during traveling and the total automatic stop time rate In any of the above, it is possible that automatic stop of the engine 1 can be permitted, that is, there is a high possibility that the storage capacity of the battery is sufficiently secured at the time of stopping thereafter. Assuming that it can be secured, the automatic stop of the engine 1 is performed while the vehicle is traveling.

  Next, the procedure of S & S control in this embodiment will be described along the flowchart of FIG. This flowchart is repeatedly executed at predetermined time intervals after the start switch 66 is turned on.

  First, in step ST1, it is determined whether the vehicle 100 is currently traveling. This determination is made based on the output signal from the vehicle speed sensor 64.

  If the vehicle 100 is at a standstill and the determination in step ST1 is NO, it is not necessary to determine whether to permit the automatic stop of the engine 1 in the traveling S & S control, the process returns as it is.

  On the other hand, when the vehicle 100 is traveling and YES is determined in step ST1, the process proceeds to step ST2 and the automatic stop condition (accelerator off, brake off, and vehicle speed equal to or more than predetermined value) is satisfied during traveling. Determine if there is.

  If the automatic stop condition is not established during traveling, and if the result of the determination in step ST2 is NO, the process proceeds to step ST3 to prohibit coasting travel. That is, the engagement of the clutch 21 and the operation of the engine 1 are continued and returned.

  If the automatic stop condition during traveling is satisfied, and the determination is YES in step ST2, the process proceeds to step ST4, and the automatic stop time rate during traveling is less than a predetermined first threshold, and the total It is determined whether the automatic stop time rate is less than a predetermined second threshold. As described above, the on-traveling automatic stop time rate is calculated by dividing the on-traveling automatic stop time for one trip by the IG-ON time for one trip. Also, the total automatic stop time rate is calculated by dividing the total automatic stop time of all trips by the IG-ON time of all trips. Each threshold is determined based on the automatic stop permission time rate calculated by the process H described above (details will be described later).

  Hereinafter, the comparison operation in step ST4 will be specifically described.

  Whether or not the automatic stop time rate during traveling is less than a predetermined first threshold is determined by the map shown in FIG. 5 (in order to determine the prohibition and permission of the automatic stop of the engine 1 according to the automatic stop time rate during traveling) Is determined on the basis of That is, the liquid temperature of the battery is estimated based on the battery temperature detected by the battery temperature sensor 67, and the liquid temperature of the battery is applied to the map of FIG. Decide. The automatic stop permission threshold (automatic stop time ratio during traveling) determined in this manner is the first threshold. Then, if the current automatic stop time rate during traveling is less than the automatic stop permission threshold (first threshold), then the automatic stop time rate during traveling can permit automatic stop of the engine 1. On the other hand, if the current automatic stop time rate during traveling is equal to or higher than the automatic stop permission threshold (first threshold), the automatic stop time rate during traveling can not permit the automatic stop of the engine 1 (prohibition It should be determined that

  For example, when the liquid temperature of the current battery is Tb in the figure, the automatic stop time rate during traveling, which is the automatic stop permission threshold (first threshold), is Rt1. Then, if the current automatic stop time rate during traveling is Rta, it is determined that the automatic stop time rate during traveling can permit the automatic stop of the engine 1, while the current automatic stop time during traveling is determined. If the rate is Rtb, it is determined that the automatic stop time rate during traveling can not allow (prohibit) the automatic stop of the engine 1.

  Whether or not the total automatic stop time rate is less than a predetermined second threshold is a map shown in FIG. 6 (a map for determining the prohibition and permission of the automatic stop of the engine 1 according to the total automatic stop time rate It is judged based on). In the map shown in FIG. 6, although the automatic stop time rate during traveling, which becomes the automatic stop permission threshold regardless of the liquid temperature of the battery, is set to a constant value, as in the map of FIG. The stop permission threshold may be changed according to the liquid temperature of the battery. Then, when the current total automatic stop time rate is less than the automatic stop permission threshold (second threshold), it is determined that the total automatic stop time rate can permit the automatic stop of the engine 1. On the other hand, if the current total automatic stop time rate is equal to or higher than the automatic stop permission threshold (second threshold), the total automatic stop time rate can not permit automatic stop of the engine 1 (should be prohibited) It is determined that

  For example, when the current total automatic stop time rate is Rtc, it is determined that the total automatic stop time rate can permit the automatic stop of the engine 1, while the current total automatic stop time rate is Rtd. If so, it is determined that the total automatic stop time rate can not be permitted (prohibited) the automatic stop of the engine 1.

  When the automatic stop time rate during traveling is less than a predetermined first threshold, and the total automatic stop time rate is less than a predetermined second threshold, and YES is determined in step ST4, the step Move to ST5 and execute coasting run. That is, since the automatic stop time rate during traveling is less than the predetermined first threshold, it is determined that the automatic stop time rate during traveling is the time rate at which the automatic stop of the engine 1 can be permitted. Since the automatic stop time rate is less than the predetermined second threshold, the engine 1 is automatically determined as the time rate at which the automatic stop of the engine 1 can be permitted even in this total automatic stop time rate. Run a coasting run to stop.

  In this way, in the state where the coasting travel is performed, if the automatic stop cancellation condition during traveling is satisfied in the next routine, the determination in step ST2 is NO, and the process proceeds to step ST3, and the course Release the running. That is, the clutch 21 is engaged and the engine 1 is restarted.

  In the determination of step ST4, at least one of the automatic stop time rate during traveling being equal to or higher than a predetermined first threshold and the total automatic stop time rate being equal to or higher than a predetermined second threshold If one is established, the determination is NO in step ST4, and the process proceeds to step ST6.

  In step ST6, it is determined whether the vehicle 100 has stopped. This determination is made based on the output signal from the vehicle speed sensor 64.

  When the vehicle 100 is not stopped, that is, the traveling state of the vehicle 100 is continuing, and the determination is NO in step ST6, the process proceeds to step ST7, and the automatic stop of the engine 1 is prohibited. That is, the operation of the engine 1 is continued. This is because there is a possibility that the remaining amount of charge of the battery is reduced by the NO determination in the step ST4, and when the vehicle 100 is stopped and the engine 1 is automatically stopped in this state, It is considered that there is a high possibility that the engine 1 will be restarted before the driver's request for starting is generated. That is, it is for avoiding giving discomfort to a passenger | crew by restarting an engine in the stop condition of a vehicle.

  On the other hand, when the vehicle 100 is stopped and YES is determined in step ST6, the process proceeds to step ST8, and it is determined whether or not this stopping time is in the stopping engine stop permission area. In this stopping engine stop permission area, a state in which the automatic stop of the engine 1 can be maintained for a predetermined time or more when the vehicle 100 stops is determined (a state determined based on the liquid temperature of the battery, the operating state of accessories, etc. Say). That is, when the liquid temperature of the battery is relatively high or the power consumption by the operation of the auxiliary devices is relatively small, the automatic stop of the engine 1 can be maintained for a predetermined time or more, so that the engine stop permission region during stop It is judged. On the other hand, when the liquid temperature of the battery is relatively low, or when the power consumption by the operation of the accessories is relatively high, there is a possibility that the automatic stop of the engine 1 can not be maintained for a predetermined time or more. It is judged not to be an area. Parameters (a liquid temperature of a battery, power consumption due to the operation of auxiliary devices, etc.) for determining whether or not the vehicle is in an engine stop permitting area during such a stop are set based on experiments or simulations.

  If it is in the engine stop permission area while the vehicle is at rest, and YES is determined in step ST8, the process proceeds to step ST9, and the engine 1 is automatically stopped. That is, while the vehicle is stopped, the automatic stop of the engine 1 is performed by the S & S control.

  On the other hand, when it is not in the engine stop permission area while the vehicle is stopped and the determination is NO in step ST8, the process proceeds to step ST7 to prohibit the automatic stop of the engine 1. That is, the operation of the engine 1 is continued. This is for securing the power for auxiliary machinery operation.

  The above operation is repeated. Therefore, the operation of the steps ST1, ST2, ST4 and ST5 is the automatic stop control unit according to the present invention (when the automatic stop condition during traveling is satisfied while the vehicle is traveling, the automatic stop time ratio during traveling is predetermined). This is equivalent to the operation of the automatic stop control section for automatically stopping the internal combustion engine while the vehicle is traveling when the total automatic stop time rate is less than the threshold of 1 and the total automatic stop time rate is less than the predetermined second threshold.

  As described above, in the present embodiment, when the automatic stop condition during traveling is satisfied while the vehicle 100 is traveling, the automatic stop time ratio during traveling is less than the predetermined first threshold, and the total automatic stop time ratio is If it is less than the predetermined second threshold, the engine 1 is automatically stopped while the vehicle 100 is traveling. That is, when the automatic stop time rate during traveling is less than the predetermined first threshold, the amount of discharge of the battery during traveling is small, and even if the vehicle is stopped thereafter, the engine 1 stop continuation time by the S & S control during stoppage is secured long It is judged that it can be done. Similarly, even if the total automatic stop time rate is less than the predetermined second threshold, the amount of battery discharge is small, and even if the vehicle is stopped thereafter, a long stop duration of the engine 1 by the S & S control can be secured. It is determined that Based on this determination, when both of these conditions are satisfied, the engine 1 is automatically stopped to allow discharge of the battery while traveling. In other words, while the condition (condition of each automatic stop time rate) is satisfied, the engine 1 is automatically stopped in response to the automatic stop condition being satisfied during traveling. As a result, there is a high possibility that the storage capacity of the battery is still sufficiently secured at the time of the subsequent stop, and a long duration of stop of the engine 1 by the S & S control during the stop can be secured. As a result, the possibility that the engine 1 is restarted while the vehicle 100 is in a stopped state is reduced, and the fuel consumption rate can be improved. In addition, it is possible to suppress the discomfort of the occupant due to the sound or vibration accompanying the restart of the engine 1.

-Other embodiment-
The embodiment disclosed this time is an exemplification in all respects and is not a basis for a limited interpretation. Therefore, the technical scope of the present invention is not interpreted only by the above-mentioned embodiment, but is defined based on the statement of a claim. Further, the technical scope of the present invention includes all modifications within the meaning and scope equivalent to the claims.

  For example, although the said embodiment demonstrated the case where this invention was applied to the vehicle carrying a gasoline engine, this invention is applicable also to the vehicle carrying a diesel engine.

  Further, in the above embodiment, in calculating the automatic stop time rate during traveling, the automatic stop time during traveling in the current trip is divided by the IG-ON time of the current trip. The present invention is not limited to this, and the automatic stop time ratio during traveling may be calculated by dividing the automatic stop during traveling in the previous one trip by the IG-ON time of the previous one trip. According to this, even if the automatic stop condition during traveling is satisfied at the initial stage of the start of the trip, whether or not the engine is automatically stopped during traveling is appropriately determined according to the remaining charge amount of the battery. It becomes possible to judge.

  The present invention is applicable to control for improving the fuel consumption rate in a vehicle capable of automatically stopping the engine while the vehicle is traveling and stopping.

1 Engine (internal combustion engine)
21 clutch 5 ECU
62 accelerator opening sensor 62a accelerator pedal 64 vehicle speed sensor 65 brake pedal sensor 65a brake pedal 66 start switch 67 battery temperature sensor 71 injector 74 hydraulic control unit 100 vehicle

Claims (1)

Automatic stop control during running that automatically stops the internal combustion engine when a predetermined running automatic stop condition is met while the vehicle is running, and the internal combustion engine is automatically operated when the predetermined stop automatic stop condition is met during the vehicle stop. In a control device applied to a vehicle capable of automatic stop control during a stop while stopping
An automatic stop time ratio calculating unit for calculating an automatic stop time ratio during traveling which is a ratio of an automatic stop time of the internal combustion engine to a period during which the vehicle is running with respect to ignition ON continuation time in one trip
A total automatic stop time ratio calculating unit that calculates a total automatic stop time ratio which is a ratio of the total automatic ON time of the internal combustion engine to the total ignition ON time after the storage battery is mounted;
The automatic stop time rate during traveling is less than a predetermined first threshold and the total automatic stop time rate is less than a predetermined second threshold when the automatic stop condition is satisfied while the vehicle is moving. A control device for a vehicle, comprising: an automatic stop control unit for automatically stopping the internal combustion engine while the vehicle is traveling, if any.

Images