JP2004019448A - Automatic stop control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic stop control device for securing the opportunities of automatically stopping an internal combustion engine. <P>SOLUTION: An ECU 38 detects the presence or not of a travel history of a vehicle after starting the engine 2 and erases information about the presence of the travel history when preset stopping conditions are not established. Herein, the ECU 38 holds the presence of a previous travel history when the information about the presence of the travel history is erased. The ECU 38 allows the automatic stop of the engine 2 if there is the information about the presence of the travel history or if there is the information about the presence of the previous travel history when the stopping conditions are established. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an automatic stop control device for an internal combustion engine, and more particularly to an automatic stop control device for an internal combustion engine that automatically stops the internal combustion engine when the operation state of the internal combustion engine is a predetermined operation state when the vehicle stops.
[0002]
[Prior art]
In order to improve fuel efficiency and reduce emissions, the internal combustion engine mounted on the vehicle automatically stops when the vehicle stops running at an intersection, etc., and automatically starts the internal combustion engine by rotating the electric motor when starting. There is known an automatic stop control device that enables the vehicle to start.
[0003]
BACKGROUND ART Conventionally, as an automatic stop control device for an internal combustion engine of this type, for example, a device disclosed in Japanese Patent Application Laid-Open No. 2000-337188 is known. According to this conventional technique, when a predetermined stop condition is satisfied based on the operating states of the vehicle and the internal combustion engine during operation of the internal combustion engine, the internal combustion engine is automatically stopped, and while the internal combustion engine is stopped, the predetermined start condition is satisfied. In such a case, the internal combustion engine is automatically started by driving the electric motor. Then, after the internal combustion engine is started using the ignition key, if there is no predetermined traveling history, the automatic stop of the internal combustion engine is prohibited even if the stop condition is satisfied.
[0004]
By employing such a configuration, it is possible to prevent the internal combustion engine from being unable to start due to insufficient charging of the battery at the time of automatic start after automatic stop of the internal combustion engine. .
[0005]
However, in the automatic stop control device described in the above-mentioned publication, once the information indicating the running history based on the running of the vehicle after the internal combustion engine is started by turning on the ignition key is stored, the information indicating the running history is stored. Is not erased until the ignition key is turned off. Therefore, if a predetermined stop condition is satisfied when the vehicle is stopped, the internal combustion engine is automatically stopped. If the predetermined start condition is satisfied while the internal combustion engine is stopped, the internal combustion engine is automatically started. Therefore, the automatic stop and the automatic start of the internal combustion engine may be frequently performed, and the life of the battery and the life of the electric motor may be shortened.
[0006]
In order to solve this problem, an automatic stop control device that inhibits the automatic stop control of the internal combustion engine by deleting the running history up to that time when the predetermined stop condition is not satisfied may be considered. According to this automatic stop control device, the frequency of executing the automatic stop and the automatic start of the internal combustion engine can be suppressed, and the shortening of the life of the battery and the life of the electric motor can be suppressed.
[0007]
[Problems to be solved by the invention]
However, in such an automatic stop control device, when the predetermined stop condition is not satisfied when the vehicle stops, and when the predetermined stop condition is satisfied while the vehicle stops, the driving history until the vehicle stops is erased. Although the condition is satisfied, the internal combustion engine cannot be automatically stopped. For this reason, the opportunity for automatically stopping the internal combustion engine is reduced, and it is not possible to improve fuel efficiency and reduce emissions.
[0008]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide, even when a predetermined stop condition of an internal combustion engine is not satisfied during a stop of a vehicle, a predetermined travel history before a stop of the vehicle. An object of the present invention is to provide an automatic stop control device for an internal combustion engine that can perform an automatic stop to secure an opportunity for the automatic stop of the internal combustion engine.
[0009]
[Means for Solving the Problems]
Hereinafter, the means for achieving the above object and the effects thereof will be described.
The invention as set forth in claim 1 is characterized in that history detecting means for detecting the presence or absence of a running history of the vehicle after the start of the internal combustion engine mounted on the vehicle, and the running when the predetermined stop condition for stopping the internal combustion engine is not satisfied. History management means for erasing information with history, and automatic stop control means for automatically stopping the internal combustion engine when there is information with travel history when the stop condition is satisfied during operation of the internal combustion engine. In the internal combustion engine automatic stop control device provided, the history management means holds at least the previous travel history when erasing the information with at least the travel history, and the automatic stop control means, when the stop condition is satisfied The automatic stop of the internal combustion engine is performed when there is information with the travel history or when there is information with the previous travel history.
[0010]
According to the above configuration, when the predetermined stop condition is not satisfied when the vehicle stops, and when the predetermined stop condition is satisfied while the vehicle stops, the information indicating that the vehicle has a travel history is deleted. At the time of deletion, information indicating that there is a previous travel history is retained. Therefore, when the predetermined stop condition of the internal combustion engine is not satisfied during the stop of the vehicle, the automatic stop of the internal combustion engine is performed based on the information on the previous travel history, and the opportunity for the automatic stop of the internal combustion engine is secured. It is possible to improve fuel efficiency and reduce emissions.
[0011]
According to a second aspect of the present invention, in the automatic stop control device for an internal combustion engine according to the first aspect, the automatic stop control means is configured to execute the automatic stop control based on the satisfaction of the stop condition after a predetermined time has elapsed after the start of the internal combustion engine. And automatically stopping the internal combustion engine.
[0012]
According to the above configuration, when the predetermined stop condition is not satisfied, the information indicating that the vehicle has a traveling history is deleted, but the information indicating that the vehicle has a previous traveling history is retained. When the predetermined stop condition of the internal combustion engine is satisfied from not being satisfied while the vehicle is stopped, the automatic stop of the internal combustion engine is performed based on the information on the previous travel history, but the stop condition is determined after a lapse of a predetermined time after the start of the internal combustion engine. The internal combustion engine is stopped based on the establishment of. Therefore, frequent automatic stop of the internal combustion engine can be suppressed, and shortening of the battery life and the life of the electric motor can be suppressed.
[0013]
According to a third aspect of the present invention, in the automatic stop control system for an internal combustion engine according to the first or second aspect, the history detecting means determines that a traveling vehicle speed of the vehicle after the start of the internal combustion engine is equal to or higher than a predetermined value. Based on this, it is detected that there is a travel history.
[0014]
As in the above configuration, it is possible to easily detect the presence of the traveling history based on the fact that the traveling vehicle speed of the vehicle after the start of the internal combustion engine has become equal to or higher than a predetermined value.
The invention according to claim 4 is the automatic stop control device for an internal combustion engine according to any one of claims 1 to 3, further comprising: an electric motor for starting the internal combustion engine; Automatic start control means for automatically starting the internal combustion engine by driving the electric motor under predetermined start conditions.
[0015]
According to the above configuration, the internal combustion engine is automatically started by driving the electric motor under predetermined starting conditions while the internal combustion engine is stopped.
According to a fifth aspect of the present invention, in the automatic stop control device for an internal combustion engine according to the fourth aspect, the information indicating that the previous travel history is present is deleted when a vehicle speed after the automatic start of the internal combustion engine is detected. Features.
[0016]
As in the above configuration, the information indicating that there is a previous travel history is deleted when the vehicle speed is detected after the automatic start of the internal combustion engine. Therefore, while the vehicle is stopped, the internal combustion engine must be reliably stopped while the stop condition is satisfied. Can be stopped.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a system configuration diagram of an internal combustion engine to which the above-described invention is applied and a control device thereof. Here, a gasoline engine (hereinafter, referred to as "engine") 2 is used as an internal combustion engine. The engine 2 is mounted on a vehicle for driving an automobile, and is controlled so that the engine 2 automatically stops and automatically starts when the vehicle enters a predetermined driving state described later.
[0018]
The power generated by the engine 2 is output from the crankshaft 2a of the engine 2 to the output shaft 6b via the torque converter 4 and the automatic transmission (hereinafter referred to as "A / T") 6, and finally to the wheels. Is transmitted.
[0019]
The power generated by the engine 2 is transmitted to the transmission belt 14 via the electromagnetic clutch 10 and the pulley 12 connected to the crankshaft 2a. The other pulleys 16, 18, and 20 are rotated by the power transmitted by the transmission belt. The electromagnetic clutch 10 can switch between transmission and non-transmission of power between the pulley 12 and the crankshaft 2a as needed.
[0020]
A power steering pump 22 as an accessory is driven by the rotation of the pulley 16 to generate a hydraulic pressure for power steering. An air conditioner (air conditioner) compressor 24 as an auxiliary machine is driven by the rotation of the pulley 18. Further, a motor generator (hereinafter, referred to as “M / G”) 26 is driven by rotation of the pulley 20, and in this case, the M / G 26 functions as a generator. M / G 26 is electrically connected to inverter 28. The inverter 28 switches to charge the electric energy from the M / G 26 to the battery 30 by switching.
[0021]
Further, when the engine 2 is automatically stopped and the engine 2 is stopped, when a drive request for the power steering pump 22 or the air conditioner compressor 24 occurs, the electromagnetic clutch 10 is released and the M / G 26 is electrically driven. Functions as a motor. In this case, inverter 28 adjusts the supply of electric energy from battery 30 as a power source to M / G 26 based on a current command input from an electronic control unit (hereinafter referred to as “ECU”) 38. The function of varying the rotation speed of the M / G 26 is achieved.
[0022]
Further, in the automatic start process after the automatic stop of the engine 2, the electromagnetic clutch 10 is connected, and in this state, the M / G 26 rotates the crankshaft 2 a of the engine 2 to perform cranking and start the engine 2. Let it.
[0023]
The ECU 38 includes an output shaft speed sensor for detecting the rotation speed of the output shaft 6b of the A / T 6, an idle switch for detecting whether or not the accelerator pedal is depressed, and an accelerator opening for detecting the amount of depression of the accelerator pedal (accelerator opening ACCP). The detection value of the degree sensor is input. The ECU 38 also has a throttle opening sensor for detecting the opening (throttle opening TA) of a throttle valve 2c provided in the intake path 2b to the engine 2 for adjusting the intake air amount, and a shift position SHFT of the A / T6. Is detected by the shift position sensor that detects the shift. Further, the ECU 38 is provided with input values of an engine speed sensor for detecting the engine speed NE, an eco-run switch for instructing the driver to execute the eco-run system, and air-conditioner switches for driving the air conditioner. Further, ECU 38 receives a brake switch for detecting whether the brake pedal is depressed, a water temperature sensor for detecting the engine cooling water temperature THW, or other sensors.
[0024]
The ECU 38 is mainly configured by a microcomputer, and executes necessary arithmetic processing according to a program written in an internal ROM. The ECU 38 controls the throttle valve motor 2d for adjusting the opening of the throttle valve 2c, the fuel injection valve 42 for supplying fuel to the intake port or the combustion chamber of the engine 2 or an igniter, and other actuators based on the calculation result. To suitably control the engine 2 and the A / T 6.
[0025]
When the driver turns on the eco-run switch and the vehicle enters a predetermined driving state, the ECU 38 executes an automatic stop process and an automatic start process of the engine 2.
[0026]
In the automatic stop processing of the engine 2, the ECU 38 determines whether or not the automatic stop condition is satisfied based on an operation state for determining whether to execute the automatic stop. The operating state includes, for example, the engine coolant temperature THW detected by the water temperature sensor, the accelerator pedal depression detected by the idle switch, the voltage of the battery 30, the brake pedal detected by the brake switch. , And a vehicle speed SPD obtained by conversion from the detection value of the output shaft speed sensor.
[0027]
In the present embodiment, the automatic stop condition of the engine 2 includes a plurality of items described below. For example, (1) the engine 2 has been warmed up and has not been overheated (the engine cooling water temperature THW is lower than the water temperature upper limit THWmax and higher than the water temperature lower limit THWmin). (2) The accelerator pedal is not depressed (idle switch on). (3) The state where the charge amount of the battery 30 is not less than a certain level (the battery voltage is not less than the reference voltage). (4) The brake pedal is depressed (brake switch on). (5) The vehicle is in a stopped state (vehicle speed SPD is 0 km / h). When all of these conditions (1) to (5) are satisfied, the ECU 38 determines that the automatic stop condition has been satisfied.
[0028]
Also, the ECU 38 permits the automatic stop of the engine 2 when there is a predetermined traveling history of the vehicle after starting the engine 2 as one of the conditions for automatically stopping the engine 2. The automatic stop of the engine 2 is prohibited. In the present embodiment, the ECU 38 detects that there is a travel history based on the fact that the travel speed of the vehicle after the start of the engine 2 has reached a predetermined value or more as the travel history. By adopting such a configuration, it is possible to prevent the engine 2 from being unable to start due to insufficient charging of the battery 30 at the time of automatic start after the automatic stop of the engine 2.
[0029]
By the way, if the information indicating that there is a running history of the vehicle is detected after the engine 2 is started, and if the information indicating that there is a running history is not deleted until the engine 2 is stopped based on the operation of turning off the ignition key, when the vehicle is stopped, If the automatic stop condition is satisfied, the ECU 38 automatically stops the engine 2. When the automatic start condition is satisfied during the automatic stop of the engine 2 by the ECU 38, the automatic start of the engine 2 is performed by the ECU 38. Therefore, the automatic stop and the automatic start of the engine 2 may be frequently performed. If the automatic stop / automatic start of the engine 2 is frequently repeated, the life of the battery 30 may be shortened, or the life of the M / G 26 may be shortened.
[0030]
Therefore, in the present embodiment, when the automatic stop condition is not satisfied during the operation after the start of the engine 2, the ECU 38 deletes information indicating that there is a running history of the vehicle after the start of the engine 2. By adopting such a configuration, the engine 2 is automatically stopped when the latest traveling history exists when the automatic stop condition is satisfied. As a result, the execution frequency of the automatic stop and the automatic start of the engine 2 is suppressed, and the shortening of the battery life and the life of the electric motor can be suppressed.
[0031]
Further, when erasing the information indicating that the travel history is present, the ECU 38 retains the information indicating that the travel history is present at least once during the operation of the engine 2 at that time. The information on the presence of the previous travel history is also one of the automatic stop conditions of the engine 2. The ECU 38 determines that the automatic stop condition is satisfied during the operation of the engine 2 when the previous travel history exists without the travel history. Is designed to automatically stop the engine 2.
[0032]
This is because despite the fact that the automatic stop condition that was not satisfied when the vehicle was stopped is satisfied while the vehicle is stopped, the information indicating that there is a running history until the vehicle stopped is erased. As a result, the engine 2 cannot be automatically stopped, and the opportunity for automatically stopping the engine 2 is reduced. Therefore, by retaining the information on the last running history when deleting the information on the running history, there is information on the last running history even if there is no information on the running history when the automatic stop condition of the engine 2 is satisfied. In such a case, the engine 2 is automatically stopped, so that an opportunity to automatically stop the engine 2 can be secured.
[0033]
Further, when the automatic stop condition is satisfied, the ECU 38 permits the automatic stop of the engine 2 if the elapsed time tas after the start of the engine 2 is not equal to or longer than the predetermined time t0, even if there is information indicating that there is a previous running history. Not to be.
[0034]
If the driver stops the vehicle at an intersection or the like and the automatic stop condition is satisfied, and the stop of the engine 2 is permitted, the ECU 38 executes an engine stop process. In the engine stop processing, for example, the fuel injection from the fuel injection valve 42 is stopped, and the ignition control of the air-fuel mixture in the combustion chamber of the engine 2 by the spark plug is also stopped. As a result, fuel injection and ignition are stopped, and the operation of the engine 2 is immediately stopped.
[0035]
Further, in the automatic start process of the engine 2, the ECU 38 determines whether or not the automatic start condition is satisfied based on an operation state for determining whether to execute the automatic start. Here, the operation state includes, for example, the same engine-cooling water temperature THW, accelerator opening ACCP, battery 30 voltage, brake switch state, vehicle speed SPD, and the like as the data read in the automatic stop condition determination processing. .
[0036]
In the present embodiment, the automatic start condition of the engine 2 includes the following items. For example, under the condition that the engine is in the stopped state by the automatic stop processing, (1) the state in which the engine 2 has been warmed up and is not overheated (the engine cooling water temperature THW is lower than the water temperature upper limit value THWmax and the water temperature Higher than the lower limit value THWmin). (2) The accelerator pedal is not depressed (idle switch on). (3) The state where the charge amount of the battery 30 is not less than a certain level (the battery voltage is not less than the reference voltage). (4) The brake pedal is depressed (brake switch on). (5) The vehicle is in a stopped state (vehicle speed SPD is 0 km / h). If any one of these conditions (1) to (5) is not satisfied, the ECU 38 determines that the automatic start condition has been satisfied. The above-mentioned automatic start conditions (1) to (5) have the same contents as the respective conditions used in the automatic stop condition. However, the present invention is not limited thereto, and conditions other than the conditions (1) to (5) may be used. May be set. Further, the conditions may be narrowed down to some of the conditions (1) to (5).
[0037]
If any one of the above conditions (1) to (5) is not satisfied in the engine stop state by the automatic stop process, the ECU 38 executes the automatic start process of the engine 2. The ECU 38 rotates the crankshaft 2a of the engine 2 by driving the M / G 26 with the electromagnetic clutch 10 in the connected state, and executes a fuel injection process at the time of starting and an ignition timing control process to start the engine 2. Start automatically. When the start of the engine 2 is completed, the ECU 38 starts normal fuel injection amount control processing, ignition timing control processing, and other processing necessary for engine operation.
[0038]
Next, an automatic stop process and an automatic start process of the engine 2 executed by the ECU 38 will be described. These automatic stop processing and automatic start processing are executed when the driver turns on the eco-run switch.
[0039]
FIG. 2 shows a flowchart of the automatic stop processing. This process is a process that is periodically and repeatedly executed every preset short time. When the automatic stop processing is started, first, an operation state for determining execution of automatic stop is read (step 110). For example, it is obtained from the engine coolant temperature THW, the presence / absence of depression of an accelerator pedal detected by an idle switch, the charge amount of the battery 30, the presence / absence of depression of a brake pedal detected by a brake switch, and a detection value of an output shaft speed sensor. The read vehicle speed SPD and the like are read into a work area of a RAM in the ECU 38.
[0040]
Next, it is determined whether or not the automatic stop condition is satisfied based on these operating states (step 120). For example, (1) the engine 2 has been warmed up and has not been overheated (the engine cooling water temperature THW is lower than the water temperature upper limit THWmax and higher than the water temperature lower limit THWmin). (2) The accelerator pedal is not depressed (idle switch on). (3) The state where the charge amount of the battery 30 is not less than a certain level (the battery voltage is not less than the reference voltage). (4) The brake pedal is depressed (brake switch on). And (5) the vehicle is stopped (vehicle speed SPD is 0 km / h). When all of these conditions (1) to (5) are satisfied, the ECU 38 determines that the automatic stop condition is satisfied, and when any one of the above conditions (1) to (5) is not satisfied, the ECU 38 determines whether the automatic stop condition is satisfied. It is determined that the stop condition is not satisfied.
[0041]
If it is determined that the automatic stop condition is not satisfied ("NO" in step 120), it is next determined whether or not a travel history flag indicating travel history presence information is ON (step 170). When there is a travel history, the travel history flag is set to ON, and when there is no travel history, the travel history flag is set to OFF.
[0042]
When it is determined that the traveling history flag is ON ("YES" in step 170), the traveling history flag is cleared and turned off (step 180), and then the previous traveling history flag is set to ON (step 170). 190). The previous travel history flag is for storing the presence / absence information of the previous travel history indicating whether or not the travel history is present at least once during the operation of the engine 2. The traveling history flag is set to ON.
[0043]
Since the automatic stop condition has not been satisfied at the time when the traveling history flag was set to ON in the previous time in step 190, the execution of the automatic stop control is prohibited (step 200), and the present process is ended once.
[0044]
On the other hand, if it is determined in step 170 that the traveling history flag is OFF, execution of the automatic stop control is prohibited (step 200), and the present process is ended once. If the automatic stop condition is satisfied ("YES" in step 120), it is then determined whether to permit the automatic stop of the engine 2 based on whether or not the travel history flag is ON (step 130).
[0045]
If it is determined that the travel history flag is OFF ("NO" in step 130), it is determined whether the previous travel history flag is ON (step 150). If it is determined that the previous travel history flag is ON ("YES" in step 150), the execution of the automatic stop control is prohibited (step 200), and the process is terminated once.
[0046]
On the other hand, if it is determined that the previous travel history flag is ON ("NO" in step 150), it is determined whether the elapsed time tas after the current start of the engine 2 is equal to or longer than a predetermined time t0 (step 160). . Here, if the elapsed time tas is less than the predetermined time t0 ("NO" in step 160), the execution of the automatic stop control is prohibited (step 200), and the present process is ended once.
[0047]
On the other hand, if the elapsed time tas is equal to or longer than the predetermined time t0 (“YES” in step 160), the engine stop process is executed because the automatic stop condition of the engine 2 is satisfied (step 140). For example, the fuel injection from the fuel injection valve 42 is stopped, and the ignition control of the air-fuel mixture in the combustion chamber by the spark plug is also stopped. As a result, fuel injection and ignition are stopped, and the operation of the engine 2 is immediately stopped. Thus, the present process is once ended. Thus, the automatic stop processing can be executed.
[0048]
When it is determined that the traveling history flag is ON (“YES” in step 130), the engine stop process is executed (step 140) because the automatic stop condition of engine 2 is satisfied.
[0049]
FIG. 3 shows a flowchart of the automatic start process. This process is a process that is periodically and repeatedly executed every preset short time. When the automatic start process is started, first, an operation state for judging execution of automatic start is read (step 210). Here, for example, the same data as the data read in step 110 of the automatic stop processing (FIG. 2), the engine coolant temperature THW, the accelerator opening ACCP, the charge amount of the battery 30, the state of the brake switch, the vehicle speed SPD, and the like are stored in the RAM. Read into work area.
[0050]
Next, it is determined whether or not the engine 2 is automatically stopped by the above-described automatic stop processing (FIG. 2) (step 220). If the automatic stop is not being performed ("NO" in step 220), the present process is temporarily terminated.
[0051]
On the other hand, if the automatic stop is being performed (“YES” in step 220), it is determined whether the automatic start condition is satisfied based on the operating state read in step 210 (step 230). For example, (1) the engine 2 has been warmed up and has not been overheated (the engine cooling water temperature THW is lower than the water temperature upper limit THWmax and higher than the water temperature lower limit THWmin). (2) The accelerator pedal is not depressed (idle switch on). (3) The state where the charge amount of the battery 30 is not less than a certain level (the battery voltage is not less than the reference voltage). (4) The brake pedal is depressed (brake switch on). And (5) the vehicle is stopped (vehicle speed SPD is 0 km / h). If any one of these conditions (1) to (5) is not satisfied under the condition that the engine is stopped by the automatic stop process, it is determined that the automatic start condition is satisfied.
[0052]
If the engine is not stopped due to the automatic stop processing, or if all of the above conditions (1) to (5) are satisfied even if the engine is stopped due to the automatic stop processing, the automatic start condition is determined to be unsatisfied (step (“NO” in 230), the present process is ended once.
[0053]
If any one of the above conditions (1) to (5) is not satisfied in the engine stop state by the automatic stop process, the automatic start condition is satisfied ("YES" in step 230), and the automatic start process is set to start. (Step 240), and the process ends once.
[0054]
According to the start setting of the automatic start process in step 240, the ECU 38 first drives the starter 40 to rotate the crankshaft of the engine 2, and executes the fuel injection process and the ignition timing control process at the start. Then, the engine 2 is automatically started. When the start is completed, normal fuel injection amount control processing, ignition timing control processing, and other processing necessary for engine operation are started.
[0055]
Next, an example of the automatic stop / start control in the present embodiment will be described with reference to FIG.
Now, it is assumed that the vehicle is running after the engine 2 is started. Assuming that the vehicle speed is equal to or higher than a predetermined value, the travel history flag is set to ON. At this time, since the condition for automatically stopping the engine 2 is not satisfied, the traveling history flag is cleared and set to OFF. When the first traveling history flag is cleared, the previous traveling history flag is set to ON, and the previous traveling history flag is kept ON. During the running of the vehicle, the automatic stop condition is not satisfied, so that the automatic stop control is not executed.
[0056]
Thereafter, when the vehicle stops at time T1 and the vehicle speed becomes 0, among the automatic stop conditions, for example, if the charging voltage of the battery 30 is lower than the reference voltage, the automatic stop condition is not satisfied. Therefore, the automatic stop control is not yet executed at time T1 when the vehicle stops.
[0057]
At time T2 when the vehicle is stopped, for example, when the charging voltage of the battery 30 is equal to or higher than the reference voltage and the automatic stop condition is satisfied, the elapsed time after the start of the engine 2 this time is equal to or longer than the predetermined time t0. . At this time, the traveling history flag is OFF, but since the previous traveling history flag is kept ON, the automatic stop control is executed at time T2 with the satisfaction of the automatic stop condition, and the engine 2 is automatically stopped.
[0058]
Thereafter, when the state of charge of the battery 30, for example, decreases at time T3 in the stopped state of the vehicle, the automatic stop condition is not satisfied, and the automatic start condition is satisfied. Therefore, at time T3, the automatic start control is executed, and the engine 2 is started.
[0059]
When the vehicle continues to be stopped after the engine 2 is automatically started, it is assumed that, for example, at time T4, the charging voltage of the battery 30 becomes equal to or higher than the reference voltage and the automatic stop condition is satisfied. At this time, if the last running history flag is ON, but the elapsed time after the start of the engine 2 this time is less than the predetermined time t0, the automatic stop control is not executed, and the engine 2 is maintained in the operating state. You.
[0060]
When the stopped state of the vehicle is maintained and the automatic stop condition is also maintained, the elapsed time from time T3 at time T5 reaches a predetermined time t0, at which time the previous run history flag is held ON. Therefore, at time T5, the automatic stop control is executed, and the engine 2 is automatically stopped.
[0061]
Thereafter, for example, when the brake pedal is released at time T6 while the vehicle is stopped, the automatic stop condition is not satisfied, and the automatic start condition is satisfied. Therefore, at time T6, the automatic start control is executed, and the engine 2 is started.
[0062]
Then, when it is detected at time T7 that the vehicle has started running, the previous run flag is cleared. Thereafter, when the vehicle speed reaches a predetermined value or more, the traveling history flag is turned on. However, since the automatic stop condition is not satisfied, the previous traveling history flag is set to ON when the traveling history flag is cleared, and the previous traveling history flag is set. The history flag is kept ON.
[0063]
According to the embodiment described above, the following effects can be obtained.
In the present embodiment, when the automatic stop condition is not satisfied when the vehicle stops, if the automatic stop condition is satisfied while the vehicle is stopped, the information with the travel history is deleted, but the information with the previous travel history is retained. Therefore, when the automatic stop condition of the engine 2 is not satisfied while the vehicle is stopped, the engine 2 is automatically stopped based on the information on the previous travel history, so that an opportunity for the automatic stop can be secured, thereby improving the fuel efficiency. And emission reduction.
[0064]
When the condition for automatically stopping the engine 2 is not satisfied while the vehicle is stopped, the engine 2 is automatically stopped based on the information indicating that there is a previous running history. Unless the time is t0 or more, the engine 2 is not automatically stopped. Therefore, frequent automatic stop of the engine 2 can be suppressed, and shortening of the life of the battery and the life of the electric motor can be suppressed.
[0065]
Further, since the information indicating the previous running history is deleted when the vehicle is shifted to running and the vehicle speed is detected after the engine 2 is automatically started, the automatic stop condition is satisfied while the vehicle is stopped. During this period, the engine 2 can be stopped reliably.
[0066]
Since the M / G 26 is connected to the crankshaft 2a of the engine 2 so as to be able to be connected and disconnected, the M / G 26 can perform an automatic start process of the engine 2 and when the output of the engine 2 is low. The output can be assisted by the M / G 26.
[0067]
-The electric motor can be used as a generator by using the so-called M / G26.
The embodiment can be changed as follows.
[0068]
The previous run history is stored when deleting the run history information. However, the previous run history may be stored when the run history is detected.
[0069]
Although the running history is detected when the vehicle speed is equal to or higher than the predetermined value, the driving history may be detected when the running time of the vehicle after starting the engine is equal to or longer than the predetermined time. .
[0070]
Next, other technical ideas that can be grasped from the above embodiments will be described below.
In the automatic stop control device for an internal combustion engine according to claim 1 or 2, the history detection means is configured to determine a travel history based on that an average vehicle speed during a vehicle travel after the start of the internal combustion engine becomes equal to or higher than a predetermined value. An automatic stop control device for an internal combustion engine, which detects the presence.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram of an internal combustion engine and a control device thereof according to an embodiment.
FIG. 2 is a flowchart illustrating an automatic stop process executed by an ECU according to one embodiment.
FIG. 3 is a flowchart illustrating an automatic start process executed by the ECU according to the embodiment;
FIG. 4 is a time chart showing an example of an automatic stop / automatic start process.
[Explanation of symbols]
2 engine, 2a crankshaft, 2b intake path, 2c throttle valve, 2d throttle valve motor, 4 torque converter, 6 A / T, 6b output shaft, 10 electromagnetic clutch, 12 pulley, 14 ... transmission belt, 16, 18, 20 ... pulley, 22 ... power steering pump, 24 ... air conditioner compressor, 26 ... motor generator (M / G), 28 ... inverter, 30 ... battery, 38 ... history detection means, ECU as history management means, automatic stop control means and automatic start control means, 40: starter, 42: fuel injection valve, SPD: vehicle speed.

Claims (5)

History detection means for detecting the presence or absence of a running history of the vehicle after the start of the internal combustion engine mounted on the vehicle,
History management means for erasing the information with the travel history when a predetermined stop condition for stopping the internal combustion engine is not satisfied,
When the stop condition is satisfied during the operation of the internal combustion engine, if there is information indicating that there is the travel history, the automatic stop control device for the internal combustion engine includes an automatic stop control unit that automatically stops the internal combustion engine.
The history management unit holds at least the previous travel history when erasing at least the information with the travel history,
The automatic stop control means, when the stop condition is satisfied, when there is the information with the travel history or when there is the information with the previous travel history, the automatic stop of the internal combustion engine is performed. Automatic stop control device for an internal combustion engine. The automatic stop control device for an internal combustion engine according to claim 1,
The automatic stop control device for an internal combustion engine, wherein the automatic stop control means permits automatic stop of the internal combustion engine based on satisfaction of the stop condition after a predetermined time has elapsed after the start of the internal combustion engine. The automatic stop control device for an internal combustion engine according to claim 1 or 2,
The automatic stop control device for an internal combustion engine according to claim 1, wherein the history detection means detects that a travel history exists based on a traveling vehicle speed of the vehicle after the start of the internal combustion engine being equal to or higher than a predetermined value. The automatic stop control device for an internal combustion engine according to any one of claims 1 to 3,
Further, an electric motor for starting the internal combustion engine, and automatic start control means for automatically starting the internal combustion engine by driving the electric motor under a predetermined start condition while the internal combustion engine is stopped are provided. An automatic stop control device for an internal combustion engine, comprising: The automatic stop control device for an internal combustion engine according to claim 4,
The automatic stop control device for an internal combustion engine, wherein the information indicating that there is the previous travel history is deleted when a vehicle speed is detected after the automatic start of the internal combustion engine.

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