JP4028361B2 - Engine automatic stop / start control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine automatic stop start control device that controls automatic stop or start of an engine.
[0002]
[Prior art]
Vehicles equipped with an engine as a drive source are equipped with so-called idle stop control that automatically stops the engine by stopping fuel supply under certain conditions, such as when the vehicle is stopped, for the purpose of improving fuel economy and reducing exhaust emissions. There is something to do. This idle stop control is performed not only in a general vehicle using only an engine as a drive source but also in a so-called hybrid vehicle using an engine and a motor as drive sources.
[0003]
By the way, when the engine is started due to depression of the accelerator pedal, demand for indoor air conditioning, or a decrease in the remaining battery capacity of the engine starting battery during idling stop, the engine is started after confirming that the brake is operated. . Here, operation confirmation of the brake generally are carried at a brake switch for detecting whether the brake pedal is depressed, the brake is determined to be activated when the brake switch is is ON.
[0004]
Patent Document 1 discloses engine stop control for stopping an engine based on a depression amount and a depression time of a brake pedal. In Patent Document 1, regarding engine starting, engine starting is prohibited when the amount of depression of the brake pedal is greater than or equal to a predetermined value, and the engine is turned off when the amount of depression of the brake pedal is less than the predetermined value. It is disclosed to start.
[0005]
[Patent Document 1]
JP-A-9-154205
[Problems to be solved by the invention]
However, when the engine is started when it is determined that the brake pedal is depressed because the brake switch is ON when the start request is made during idle stop, the brake pedal depression amount is extremely shallow. There is a possibility that shock will be transmitted to the driver due to the generation of driving force after starting, and it may make the driver feel uncomfortable.
Therefore, the present invention can start the engine after confirming that the brake is surely operating when a start request is made during the automatic engine stop, and can make the driver feel uncomfortable. An automatic stop / start control device for an engine is provided.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the invention of claim 1, engine (e.g., engine 1 in the embodiment described below) automatic stop for determining whether there is an engine start request during the automatic stop of the In an engine automatic stop / start control device provided with a start determination means, an operation detection means (for example, a brake switch 23 in an embodiment described later) and an oil pressure detection means (for example, a brake hydraulic pressure detection means) for detecting the brake hydraulic pressure. The automatic stop / start determination means (for example, steps S101 to S105 in the later-described embodiment) has requested to start the engine during the automatic engine stop . detected hydraulic pressure Tokoro when the said actuation detection means detects the brake actuation and the hydraulic detecting means Allow engine start if the value above, when the oil pressure of the brake actuation is detected by be detected the hydraulic detecting means is less than the predetermined value by the operation detecting means prohibits the engine start characterized in that it.
If the hydraulic pressure of the brake is greater than or equal to a predetermined value, a predetermined braking force is generated. Therefore, by configuring as described above, a brake that reliably generates a predetermined braking force when a start request is made during automatic engine stop. The engine can be started in the operating state. Further, even if a driving force is generated by starting the engine, it is possible to prevent a shock or the like from being transmitted to the driver.
[0008]
Further , when there is a start request during the automatic engine stop, if there is a possibility that a predetermined braking force cannot be obtained even if the brake is operated, the engine start can be surely prohibited.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of an automatic stop / start control apparatus for an engine according to the present invention will be described with reference to the drawings of FIGS.
FIG. 1 is a schematic configuration diagram of a parallel hybrid vehicle 100 provided with an engine automatic stop / start control device. In this hybrid vehicle 100, an engine 1 as a power source, a motor / generator 2, and an automatic transmission 3 are directly connected in series. The motor / generator 2 is an electric motor capable of generating power, and the driving forces of both the engine 1 and the motor / generator 2 are transmitted to the drive wheels W via the automatic transmission 3. Further, when the driving force is transmitted from the driving wheel W side to the motor / generator 2 side during deceleration of the hybrid vehicle 100, the motor / generator 2 functions as a generator to generate a so-called regenerative braking force, and the kinetic energy of the vehicle body. Is recovered as electrical energy.
[0010]
The output shaft 1 a of the engine 1 is connectable to an engine-driven air conditioner compressor 6 via a pulley / belt mechanism 4 and an electromagnetic clutch 5. The operation control of the air conditioner compressor 6 is performed by engaging / disengaging the electromagnetic clutch 5 controlled by the ECU 7, and by engaging the electromagnetic clutch 5, the engine 1 and the air conditioner compressor 6 are connected, and the air conditioner compressor 6 is in an operating state. By opening the electromagnetic clutch 5, the engine 1 and the air conditioner compressor 6 are disconnected, and the air conditioner compressor 6 is deactivated.
The motor / generator 2 is driven and regenerated by a power drive unit (PDU) 8 in response to a control command from the ECU 7. The power drive unit 8 is connected to a motor / generator 2 and a high-voltage battery 9 for transferring electric energy. The battery 9 is configured, for example, by connecting a plurality of modules in series with a module in which a plurality of cells are connected in series as one unit.
[0011]
The battery 9 is connected to the downverter 10 and the inverter 11. The downverter 10 controlled by the ECU 7 steps down the voltage of the battery 9 to supply power to each auxiliary device 12 driven by 12 volts, and is controlled by the ECU 7. The inverter 11 converts the DC power of the battery 9 into AC power and supplies power to the air conditioner compressor 13 driven by the motor.
As described above, the hybrid vehicle 100 includes the engine-driven air conditioner compressor 6 and the motor-driven air conditioner compressor 13 as vehicle interior air conditioner compressors. 13 operations are controlled. The engine-driven air conditioner compressor 6 is operated when, for example, the motor-driven air conditioner compressor 13 alone is insufficient in cooling capacity.
[0012]
In addition, the ECU 7 performs operation control of the fuel supply amount control device 14 that controls the fuel supply amount to the engine 1 and performs automatic stop / start control of the engine under predetermined conditions. For this purpose, the ECU 7 depresses the output signal of the vehicle speed sensor 21 that detects the vehicle speed based on the rotational speed of the drive shaft of the transmission 3, the output signal of the shift position sensor 22 that detects the shift position of the transmission 3, and the brake pedal 15. An output signal of a brake switch (operation detection means) 23 for detecting whether or not the brake pedal is detected, an output signal of a brake hydraulic pressure sensor (hydraulic pressure detection means) 24 for detecting brake hydraulic pressure, and an accelerator pedal sensor 25 for detecting the depression amount of the accelerator pedal 16 Output signal, an output signal of the remaining capacity sensor 26 for detecting the remaining capacity of the battery 9, and the like. It should be noted that the brake switch 23 is set to ON in the range where the brake is effective.
[0013]
Next, start control performed when there is an engine start request during automatic stop of the engine 1 (that is, idling stop of the engine 1) when the hybrid vehicle 100 is stopped will be described with reference to the flowchart of FIG.
The flowchart shown in FIG. 2 shows an idle stop start control routine, and this idle stop start control routine is executed by the ECU 7 at regular intervals.
The idle stop is executed by stopping the fuel supply by the fuel supply amount control device 14 and stopping the engine 1 (including idling) when the driving state of the vehicle satisfies a predetermined condition.
[0014]
First, in step S101, the vehicle is judged whether or not the idle stop. If the determination result in step S101 is “NO” (not during idling stop), the execution of this routine is temporarily terminated.
Step S101 the determination result in the case of "YES" (idle stopped), the process proceeds to step S102, to determine whether the brake switch 23 is ON.
When the result of the determination in step S102 is "YES" (ON) is determined to be during braking, the process proceeds to step S103, determines whether the detected brake hydraulic pressure in the brake hydraulic pressure sensor 24 is equal to or greater than a predetermined value To do.
[0015]
If the result of the determination in step S103 is "YES" (or the predetermined value) is determined to a predetermined braking force is generated, the process proceeds to step S104, to determine whether there is an engine start request. Here, as a condition for starting the engine, for example, when depression of the accelerator pedal 16 is detected by the accelerator pedal sensor 25 or when there is a drive request for the engine-driven air conditioner compressor 6 due to a vehicle interior air conditioning request. For example, when the remaining capacity of the battery 9 detected by the remaining capacity sensor 26 is equal to or less than a predetermined value, the engine start request is determined when any of these conditions is satisfied. .
If the determination result in step S104 is “YES” (start request is present), the process proceeds to step S105, the engine start is permitted , the engine 1 is started, and the execution of this routine is once ended.
[0016]
When the result of the determination in step S102 is "NO" (the brake switch is OFF), the brake is determined not to be operated, the execution of this routine is once stopped, and continues the idle stop.
Further, when the determination result in step S103 is “NO” (the brake hydraulic pressure is smaller than a predetermined value), it is determined that there is a possibility that the predetermined braking force is not generated. Continue idling stop.
If the determination result in step S104 is “NO” (no start request), the execution of this routine is temporarily terminated and the idling stop is continued.
Therefore, even if there is an engine start request during idling stop, the start of the engine 1 is prohibited if the brake switch 23 is OFF or the brake hydraulic pressure does not exceed a predetermined value.
[0017]
As described above, according to the automatic stop / start control device for the engine 1, when there is a start request during idling stop (during automatic engine stop), the brake is reliably operated and a predetermined braking force is generated. The engine 1 can be started only occasionally. As a result, when the engine is started during idling stop, inadvertent movement of the hybrid vehicle 100 can be reliably prevented, and the stop state of the hybrid vehicle 100 can be reliably maintained. Further, even if a driving force is generated by starting the engine, a shock or the like is not transmitted to the driver.
In this embodiment, the automatic stop / start determination means is realized by executing the processing of steps S101 to S105.
[0018]
[Other Embodiments]
The present invention is not limited to the embodiment described above.
For example, although the above-described embodiment has been described with an example in which the present invention is applied to a hybrid vehicle having an engine and a motor as drive sources, the present invention is also applicable to a vehicle having only an engine as a drive source.
[0019]
【The invention's effect】
As described above, according to the first aspect of the present invention, when there is a start request during the automatic engine stop, the engine can be reliably started in a brake operating state in which a predetermined braking force is generated. As a result, the engine can be started while maintaining the stop state of the vehicle with certainty. In addition, there is an effect that a shock or the like is not transmitted to the driver even when a driving force is generated by starting the engine.
Further , when there is a request for starting during automatic engine stop, if there is a possibility that a predetermined braking force cannot be obtained even if the brake is operating, it is possible to reliably prohibit engine starting. The effect is played.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an embodiment of a hybrid vehicle provided with an engine automatic stop / start control device according to the present invention;
FIG. 2 is a flowchart showing idle stop start control in the embodiment.
[Explanation of symbols]
1 Engine 23 Brake switch (operation detection means)
24 Brake hydraulic pressure sensor (hydraulic pressure detecting means)
S101-105 Automatic stop start determination means

Claims (1)

The automatic stop and start control system for an engine having an automatic stop-start determination means during the automatic stop of the engine to determine whether there is an engine start request,
An operation detecting means for detecting the operation of the brake;
Hydraulic pressure detecting means for detecting the hydraulic pressure of the brake,
The automatic stop / start determination means detects a brake operation by the operation detection means when an engine start request is made during automatic engine stop, and the hydraulic pressure detected by the hydraulic pressure detection means is a predetermined value or more. allow engine starting in the case, characterized in that when the hydraulic pressure of the brake actuation is detected by be detected the hydraulic detecting means is less than the predetermined value for inhibiting the engine start by the operation detecting means An automatic stop / start control device for the engine.

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