JP2004003514A - Economic running control method for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inhibit economic running control until the end of learning of an engine operation condition and a condition when starting an engine in an economic running control method for the internal combustion engine. <P>SOLUTION: History of battery off after input signal processing (step S200) is checked (steps S202, S204). If there is the history of battery off, it is discriminated whether basic learning ends or not (step S206). If basic learning does not end, economic running control is inhibited (step S208). If basic learning ends already, it is discriminated whether automatic stop condition in economic running control is satisfied or not (step S210). When the economic running condition is satisfied, the engine is automatically stopped (step S212). When the automatic stop condition is not satisfied, economic running is not performed, and engine driving is continued (step S214). <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to an eco-run control method for an internal combustion engine, and more particularly, to an eco-run control method for an internal combustion engine that stops the operation of the internal combustion engine when a predetermined condition is satisfied, and a control method for the internal combustion engine that learns the operating state of the internal combustion engine. .

Conventionally, as an eco-run control method for an internal combustion engine of this type, there is a method of automatically stopping an engine when a predetermined stop condition is satisfied and automatically starting the engine when another predetermined start condition is satisfied. Has been proposed (for example, Patent Document 1). A vehicle traveling in an urban area frequently stops for a predetermined time, such as waiting for a traffic light at an intersection or waiting for a train to pass at a railroad crossing. If the engine is operated while the vehicle is stopped, energy is wasted, and it cannot contribute to efficient use of fuel. The method described above seeks to make efficient use of energy by stopping the operation of the engine when the vehicle is stopped for such a predetermined time. In this method, in addition to the automatic stop and start of the operation of the engine, the contribution of the stop of the engine to the fuel consumption is displayed to the driver.

In addition, such an eco-run control method for automatically stopping and starting the operation of the engine usually learns the operating state of the engine, for example, the effect of the air-fuel ratio and the ignition timing on the emission, and uses the learning result to perform the engine operation. The operation is controlled. In such a method, the fuel efficiency and emission are improved by this learning.

JP-A-9-2235

However, in the case of learning the operating state of the engine by automatically stopping and starting the operation of the engine and controlling the operation of the engine using the learning result, the startability is deteriorated based on the atmospheric state. May be learned as one of the engine states, or the deterioration of the startability may be erroneously determined to be due to the deterioration of the equipment.

An object of the present invention is to provide an eco-run control method for an internal combustion engine that can prohibit eco-run control until learning of an operating state of the engine or a state at the time of starting is completed.

In order to achieve the above object, an eco-run control method for an internal combustion engine according to the present invention is an eco-run control method for an internal combustion engine that stops operation of the internal combustion engine when a predetermined condition is satisfied. When the degree of learning is less than a predetermined degree, the stop of the operation of the internal combustion engine is prohibited.

Further, an eco-run control method for an internal combustion engine according to the present invention is an eco-run control method for an internal combustion engine that stops the operation of the internal combustion engine when a predetermined condition is satisfied, and checks whether there is a history of battery off. Prohibiting the stop of the operation of the internal combustion engine when it is determined that there is a history of turning off the battery and it is determined that the learning of the operating state of the internal combustion engine has not been completed. It is characterized by.

It is preferable that the learning of the operating state is learning of an air-fuel ratio. Preferably, the learning of the operating state is learning of idle speed control.

Preferably, the degree of learning of the operating state is represented by the operating time of the internal combustion engine. Preferably, the degree of learning of the operating state is represented by the number of starts of the internal combustion engine.

エ コ Eco-run control can be prohibited until learning of the operating state and starting state of the engine is completed.

Next, embodiments of the present invention will be described using examples.

FIG. 1 is a configuration diagram schematically showing the configuration of a control device 20 for an internal combustion engine to which the eco-run control method according to the present invention is applied. As shown in the figure, a control device 20 for an internal combustion engine includes an engine 22 that is an internal combustion engine, an automatic transmission 30 that changes the power from the engine 22 and transmits the power to a drive shaft 32, and a generator that can start the engine 22. , A battery 62 capable of supplying power to the motor 40 via the inverter 60 and charging with the power generated by the motor 40, and an electronic control unit 70 for controlling the entire apparatus.

The engine 22 is a gasoline-fueled internal combustion engine. One end of a crankshaft 24 as an output shaft thereof is connected to an input shaft of an automatic transmission 30, and a pulley 28 is attached to the other end via a clutch 26. ing. The operation of the engine 22 is controlled by controlling an opening degree of a throttle valve (not shown) and a valve opening time of a fuel injection valve (not shown) by an engine electronic control unit (hereinafter referred to as EG ECU) 23.

The automatic transmission 30 includes a well-known fluid torque converter that amplifies torque by the action of circulating oil and transmits the amplified torque to the rear, and a combination of a plurality of clutches and brakes to operate a plurality of forward gears and reverse gears. And a transmission composed of a stepped planetary gear mechanism in which one is selectively engaged. Although not shown, the automatic transmission 30 is provided with a hydraulic control circuit for controlling the gear position of the transmission described above. The hydraulic control circuit includes a rapid boosting circuit for quickly boosting the hydraulic pressure to a clutch for selecting a forward gear during automatic start in eco-run control for automatically stopping or automatically starting the engine 22 described later. Is provided. The engagement control of a plurality of clutches and brakes provided in the hydraulic control circuit is performed by an automatic transmission electronic control unit (hereinafter referred to as ATECU) 31 by controlling the opening and closing of a solenoid valve attached to the hydraulic control circuit. The power from the engine 22 is shifted by the automatic transmission 30 and output to the drive shaft 32, and finally output to the drive wheels 36 and 38 via a differential gear 34 attached to the drive shaft 32. .

The motor 40 is configured as a synchronous motor generator capable of generating power as described above. A reduction gear 44 is attached to the rotation shaft 42 which is an output shaft of the motor 40, and a pulley 58 is attached to the reduction gear 44. As shown, the speed reducer 44 includes a sun gear 46 attached to the rotating shaft 42, a ring gear 48, a plurality of pinion gears 50 revolving around the sun gear 46 while rotating, and a carrier 52 connecting the plurality of pinion gears 50. And a planetary gear mechanism comprising: The ring gear 48 is fixed to the case by a brake 54 and is connected to the rotating shaft 42 by a one-way clutch 56. Accordingly, when the brake 54 is engaged, the rotation of the rotary shaft 42 is transmitted to the pulley 58 at a reduced speed with the gear ratio of the planetary gear mechanism, and when the brake 54 is disengaged, the one-way clutch 56 The engagement is transmitted without being decelerated. The pulley 58 is connected to the pulley 28 by a belt 59, so that the engine 22 can be started by the motor 40 and, conversely, the motor 40 can be operated as a generator by the power of the engine 22.

The operation of the motor 40 is controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 41 via an inverter 60. The operation control of the motor 40 by the motor ECU 41 is performed by sequentially controlling the ratio of the ON time of the six transistors as the switching elements included in the inverter 60 connected to the battery 62, and controlling the current flowing through each of the three-phase coils of the motor 40. Is performed by controlling. In the embodiment, since the motor 40 is a synchronous motor generator, the battery 62 can be charged by operating the motor 40 as a generator. Control for operating the motor 40 as a generator is also performed by the motor ECU 41.

The battery 62 is configured as a chargeable / dischargeable secondary battery, and its charge state and charge / discharge are controlled by a battery electronic control unit (hereinafter referred to as a battery ECU) 63.

The electronic control unit 70 is configured as a one-chip microprocessor mainly composed of a CPU 72, and includes a ROM 74 storing a processing program, a RAM 76 temporarily storing data, an EG ECU 23, an ATECU 31, a motor ECU 41, and a battery ECU 63. A communication port (not shown) for communicating with the communication device and an input / output port (not shown) are provided. The electronic control unit 70 includes an accelerator pedal, which is a wheel speed VR, VL from wheel speed sensors 37, 39 attached to the drive wheels 36, 38, and an amount of depression of an accelerator pedal 80 detected by an accelerator pedal position sensor 81. The position AP, the brake pedal position BP, which is the amount of depression of the brake pedal 82 detected by the brake pedal position sensor 83, the shift position SP, which is the position of the shift lever 84 detected by the shift position sensor 85, is detected by the brake switch 87. A brake switch BS for turning on / off the side brake lever 86, an eco-run cut signal ECSW from an eco-run cut switch 88 which is operated when eco-run control is not performed, and an atmospheric pressure sensor 90 detect the eco-run cut signal ECSW. That the atmospheric pressure P, and the like current position signal PP from the GPS receiver 92 for detecting the current position of the vehicle by radio waves from a plurality of satellites via the input port. Also, from the electronic control unit 70, a drive signal to the clutch 26, a drive signal to the speed reducer 44, a drive signal to an eco-run indicator 89 mounted on a panel in front of the driver's seat and lit when performing eco-run control, and the like. Output via the output port. The electronic control unit 70 is also connected by a not-shown interface to a CD-ROM player 94 having a built-in CD-ROM that records map information including altitude as one of the information.

In the control device 20 for the internal combustion engine configured as described above, the electronic control unit 70 performs eco-run control for automatically stopping or automatically starting the engine 22 according to the state of the vehicle. The condition for automatically stopping the engine 22 is that when the shift lever 84 is in the N position or the P position, the vehicle is in a stopped state and the accelerator pedal 80 is not depressed, and when the shift lever 84 is in the D position, the vehicle is stopped. The state is a stopped state, the state where the accelerator pedal 80 is not depressed, and the state where the brake pedal 82 is depressed. The stopped state of the vehicle is determined by the vehicle speed V calculated from the wheel speeds VR and VL detected by the wheel speed sensors 37 and 39, and the depression state of the accelerator pedal 80 and the brake pedal 82 is detected by the accelerator pedal position sensor 81. The determination is made based on the accelerator pedal position AP and the brake pedal position BP detected by the brake pedal position sensor 83. On the other hand, the condition for automatically starting the engine 22 is a state in which such a condition for automatic stop is not satisfied. Such eco-run control is activated, for example, in a signal waiting state at an intersection when traveling in an urban area or in a train waiting state at a railroad crossing to improve the fuel efficiency of the vehicle. The electronic control unit 70 performs such eco-run control, learns the operation state of the engine 22 and the state at the time of automatic start, and determines the deterioration and life of the equipment related to the operation and start of the engine 22 based on the learning result. ing.

Next, the relationship between such eco-run control processing and learning will be described. FIG. 2 is a flowchart illustrating an example of an eco-run regulation processing routine executed by the electronic control unit 70. This routine is repeatedly executed at predetermined time intervals (for example, every 8 msec) from when an ignition key (not shown) is turned on.

When this eco-run regulation processing routine is executed, the CPU 72 of the electronic control unit 70 first executes input processing of various signals (step S200). Input signals include an accelerator pedal position AP from an accelerator pedal position sensor 81, a brake pedal position BP from a brake pedal 82, a shift position SP from a shift position sensor 85, a brake switch BS from a brake switch 87, and an eco-run cut switch 88. , An atmospheric pressure P detected by an atmospheric pressure sensor 90, a current position signal PP from a GPS receiver 92, and the like. In addition to these signals, a signal related to the degree of learning from the EG ECU 23 and a signal related to the history of turning off the battery 62 from the battery ECU 63 are also included.

The learning performed by the EG ECU 23 includes learning of the relationship between the air density and the operating state of the engine 22 and the relationship at the time of starting, and a signal from an oxygen sensor (not shown) provided in an exhaust pipe of the engine 22. This includes learning of an air-fuel ratio that is feedback-controlled based on the above, learning of idle speed control performed by opening and closing an idle speed control valve (not shown), and the like. The degree of learning can be represented by, for example, the amount of data stored in a predetermined area of the RAM 76 of the electronic control unit 70 that stores the learning content, the operation time of the engine 22, the number of starts, and the like. The history of turning off the battery 62 is performed by the battery ECU 63 by detecting whether or not the inter-terminal voltage of the battery 62 has fallen below a predetermined level in the past.

After performing the input signal processing, a process of checking whether or not there is a history of turning off the battery 62 is performed (steps S202 and S204). If there is no history of the battery 62 being turned off, this routine is terminated without any operation. If there is a history of the battery 62 being turned off, the EG ECU 23 determines whether the basic learning has been completed (step S206). Whether or not the basic learning has been completed is determined by determining whether or not the amount of data accumulated in a predetermined area of the RAM 76, which is expressed as the degree of learning, is equal to or greater than a predetermined amount, and whether the operating time of the engine 22 is equal to or greater than a predetermined time. , And whether the number of starts is equal to or more than a predetermined number of times. If it is determined that the basic learning has not been completed, the eco-run control is prohibited (step S208), and the routine ends.

On the other hand, if it is determined that the basic learning has already been completed, it is determined whether the condition for automatic stop in the eco-run control described above is satisfied (step S210). Then, a process for automatically stopping the engine 22 is executed (step S212), the routine is terminated, and when the automatic stop condition is not satisfied, a process for continuing the engine drive without executing the eco-run is executed (step S214). ), End this routine.

According to the eco-run regulation processing routine of the embodiment described above, after the battery 62 is turned off, the eco-run control can be prohibited until basic learning of the operating state and the starting state of the engine 22 is completed. The learning of the operating state of the engine 22 and the state at the time of starting includes learning of the relationship between the air density and the operating state of the engine 22 and the relation between the state at the time of starting. Is not automatically stopped and automatically started, and as a result, inconvenience due to poor startability of the engine 22, for example, acceleration of equipment such as the motor 40 for starting the engine 22 and erroneous determination of deterioration. Etc. can be avoided.

In the internal combustion engine control device 20 of the above embodiment, the motor 40 is connected to the engine 22 via the speed reducer 44, but the motor 40 may be connected to the engine 22 without the speed reducer 44.

Further, in the control device 20 for the internal combustion engine in the embodiment, the motor 40 is configured as a synchronous motor generator, but may be configured as another motor generator such as an induction motor generator or configured as a motor that does not function as a generator. No problem.

Further, in the control device 20 for the internal combustion engine in the embodiment, the automatic transmission 30 is configured as a torque converter and a stepped planetary gear mechanism. However, it is sufficient that the rotation speed of the crankshaft 24 can be changed and transmitted to the drive shaft 32. Alternatively, it may be configured as a continuously variable transmission (CVT) having a continuously variable gear ratio and a hydraulically controlled clutch.

As described above, the embodiments of the present invention have been described using the examples. However, the present invention is not limited to these examples, and may be implemented in various forms without departing from the gist of the present invention. Obviously you can get it.

1 is a configuration diagram schematically illustrating a configuration of a control device for an internal combustion engine to which an eco-run control method according to the present invention is applied. 5 is a flowchart illustrating an example of an eco-run regulation processing routine executed in the eco-run control method according to the present invention.

Explanation of reference numerals

20 control unit for internal combustion engine, 22 control engine, 23 control engine electronic control unit, 24 crankshaft, 26 clutch, 28 pulley, 30 automatic transmission, 31 control electronic control unit for automatic transmission, 32 drive shaft, 34 differential gear, 36, 38 Drive wheels, 37, 39 ， wheel speed sensor, 40 motor, 41 motor electronic control unit, 42 rotary shaft, 44 reduction gear, 46 sun gear, 48 ring gear, 50 pinion gear, 52 carrier, 54 brake, 56 one-way clutch, 58 pulley, 60 inverter, 62 battery, 63 electronic control unit for battery, 70 electronic control unit, 72 CPU, 74 ROM, 76 RAM, 80 access Pedal, 81 accelerator pedal position sensor, 82 brake pedal, 83 brake pedal position sensor, 84 shift lever, 85 shift position sensor, 86 side brake lever, 87 brake switch, 88 eco-run cut switch, 89 eco-run indicator, 90 atmospheric pressure sensor, 92 $ GPS receiver, 94 $ CD-ROM player.

Claims (6)

An eco-run control method for an internal combustion engine that stops the operation of the internal combustion engine when a predetermined condition is satisfied, wherein the stop of the operation of the internal combustion engine is prohibited when the degree of learning of the operation state of the internal combustion engine is less than a predetermined degree. An eco-run control method for an internal combustion engine. An eco-run control method for an internal combustion engine that stops operation of the internal combustion engine when a predetermined condition is satisfied, and executes a process of checking whether or not there is a history of battery off. An eco-run control method for an internal combustion engine, comprising: prohibiting the stop of the operation of the internal combustion engine when it is determined that the learning of the operating state of the internal combustion engine is not completed. に お い て The internal combustion engine eco-run control method according to claim 1 or 2, wherein the learning of the operating state is an air-fuel ratio learning. に お い て The internal combustion engine eco-run control method according to claim 1 or 2, wherein the learning of the operating state is a learning of idle speed control. に お い て The internal combustion engine eco-run control method according to claim 1 or 2, wherein the degree of learning of the operation state is represented by an operation time of the internal combustion engine. (3) The method for controlling the eco-run of an internal combustion engine according to claim 1 or 2, wherein the degree of learning of the operating state is represented by the number of starts of the internal combustion engine.

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