JP2000120460A - Hybrid automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To try to enhance fuel consumption by letting a motor efficiently function, and concurrently, try to enhance response at the time of starting. SOLUTION: It is judged by an ECU whether or not a vehicle running ahead is started to decelerate its vehicle speed, based on the change in intervehicle distance with the vehicle running ahead to be detected by an intervehicle distance sensor 1 while a vehicle is running by means of a gasoline engine. And when the vehicle running ahead is found to have been decelerated, change-over is made from running by means of a gasoline engine to running by means of a motor so as to allow regenerative braking of motor to be utilized. In addition, the stamping action of an accelerator pedal by a driver at the time of starting has been learnt by the ECU 6 in advance, while his own car is stopped behind the vehicle running ahead, and when it is found based on the change in intervehicle distance with the vehicle running ahead that the degree of acceleration of the vehicle running ahead is greater than a specified value, and when it is also judged by the ECU 6 based on the result of aforesaid learning that the degree of acceleration required by the driver is greater than the aforesaid degree of acceleration of the vehicle running ahead, the gasoline engine is driven so as to be added to the operation of the motor, so that the vehicle is thereby started.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid vehicle which combines a gasoline engine and a motor as power sources and is driven by the motor at a low speed and the gasoline engine at a high speed.

[0002]

2. Description of the Related Art In recent years, awareness of protecting the global environment has been increasing on a global scale. In particular, various measures have been taken to realize the prevention of global warming by suppressing the emission of greenhouse gases such as carbon dioxide. Attempts have been made. For example, taking a car as an example, how to reduce the amount of carbon dioxide in exhaust gas is a major problem.

As one of the measures for reducing the amount of carbon dioxide in the exhaust gas of a vehicle, a hybrid vehicle which is a practical low-emission vehicle combining a gasoline engine and a motor has been proposed.

In this hybrid vehicle, a motor and a gasoline engine are used as a power source by switching between the motor and the gasoline engine. At this time, the switching between the motor and the gasoline engine is conventionally performed by, for example, the own vehicle speed by a vehicle speed sensor, the depression amount of an accelerator pedal by a driver, and the like. This is performed based on the on / off state of the brake pedal.

That is, the gasoline engine and the motor are switched depending on whether or not the vehicle speed detected by the vehicle speed sensor is equal to or higher than a certain speed, and whether or not the depression amount of the accelerator pedal is larger than a predetermined amount, that is, the driver requests a larger acceleration torque. Switching between a gasoline engine and a motor is performed depending on whether or not it is running.

[0006]

However, in the above-described conventional switching, the switching of the power source is not performed unless, for example, the driver depresses the accelerator pedal or the depression of the accelerator pedal is reflected on the own vehicle speed. Since it is not performed, the function of the motor acting as a regenerative brake cannot be used sufficiently and effectively, and it is difficult to achieve the high response that the driver expects when starting, for example. There was a problem.

An object of the present invention is to improve the fuel efficiency by making full use of the function of the motor and to improve the response at the time of starting.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a hybrid vehicle which combines a gasoline engine and a motor as power sources and is driven by the motor at a low speed and the gasoline engine at a high speed. An inter-vehicle distance sensor that detects an inter-vehicle distance with a preceding vehicle in front of the vehicle, and the preceding vehicle starts decelerating from a change in the inter-vehicle distance with the preceding vehicle detected by the inter-vehicle distance sensor during traveling by the gasoline engine. And a switching unit for switching from running by the gasoline engine to running by the motor when the determining unit determines that the preceding vehicle has started decelerating. I have.

According to such a configuration, when the determining unit determines that the preceding vehicle is starting to decelerate from the change in the following distance from the preceding vehicle by the following distance sensor, the switching unit drives the vehicle using the gasoline engine. Is switched to running by motor. Therefore, it is possible to perform braking using the regenerative braking by the motor, and by effectively regenerating the generated energy by the regenerative braking to the power supply side of the motor,
Gasoline consumption can be further reduced to improve fuel efficiency.

Further, the present invention combines a gasoline engine and a motor as power sources, and the motor,
In a hybrid vehicle driven by a gasoline engine at a high speed, an inter-vehicle distance sensor that detects an inter-vehicle distance from a preceding vehicle ahead of the host vehicle, a learning unit that learns the accelerator pedal depressing operation by the driver when starting, and a stop unit. A change in the inter-vehicle distance from the preceding vehicle detected by the inter-vehicle distance sensor when the own vehicle is stopped behind the preceding vehicle is determined whether the acceleration of the preceding vehicle is larger than a predetermined amount, and learning by the learning unit. A determination unit that determines whether the degree of acceleration requested by the driver is large based on the result; and the determination unit determines that the degree of acceleration of the preceding vehicle is larger than a predetermined amount, and determines that the degree of acceleration requested by the driver is large. And a start control unit that starts by driving the gasoline engine in addition to the motor.

With this arrangement, the determination unit determines that the degree of acceleration of the preceding vehicle is larger than a predetermined amount based on a change in the following distance from the preceding vehicle by the following distance sensor, and that the degree of acceleration requested by the driver is large based on the result of learning by the learning unit. Is determined, the start control unit drives and starts the gasoline engine in addition to the motor. Therefore, the vehicle can be started at the acceleration required by the driver at the time of starting, and the response at the time of starting can be improved.

Further, the present invention provides an inter-vehicle distance sensor for detecting an inter-vehicle distance between the host vehicle and a preceding vehicle traveling in front of the own vehicle, and the preceding vehicle detected by the inter-vehicle distance sensor during traveling by the gasoline engine. A determination unit for determining whether or not the preceding vehicle has started decelerating from a change in the inter-vehicle distance between the vehicle and the motor from running by the gasoline engine when the determination unit determines that the preceding vehicle has started deceleration. In addition to the switching unit that switches to running, a learning unit that learns the accelerator pedal depressing operation by the driver at the time of start, and the inter-vehicle distance sensor that is detected by the inter-vehicle distance sensor when the own vehicle is stopped behind a stopped preceding vehicle. The driver requests from the change of the inter-vehicle distance with the preceding vehicle whether or not the degree of acceleration of the preceding vehicle is larger than a predetermined amount, and from the learning result by the learning section. A determination unit that determines whether the acceleration degree of the preceding vehicle is greater than a predetermined amount, and the determination unit determines that the acceleration degree required by the driver is greater. The vehicle further includes a start control unit that starts the vehicle by driving the gasoline engine in addition to the motor.

[0013] By doing so, braking is performed by using regenerative braking by the motor, thereby further reducing gasoline consumption and improving fuel efficiency, and starting at the acceleration required by the driver when starting. Can be
The response at the time of starting can be improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. However, FIG. 1 is a block diagram, and FIGS. 2 and 3 are flowcharts for explaining the operation.

In FIG. 1, reference numeral 1 denotes an inter-vehicle distance sensor which irradiates a laser beam forward while scanning at a predetermined angle and detects reflected light from a preceding vehicle ahead of the own vehicle to detect a distance from the preceding vehicle. And a laser radar for deriving the inter-vehicle distance. In addition, an inter-vehicle distance sensor 1 is provided by an image processing device or the like that processes an image captured by an imaging unit and derives an inter-vehicle distance from a temporal change of the image.
May be configured.

Further, in FIG. 1, reference numeral 2 denotes an accelerator pedal opening sensor for outputting a signal corresponding to the amount of depression of an accelerator pedal, and reference numeral 3 denotes a signal corresponding to ON / OFF of a brake lamp depending on whether or not a foot brake is depressed. A brake lamp switch 4 is an engine control unit for controlling an electronically controlled gasoline engine (not shown), and a motor control unit 5 is for controlling a DC motor (not shown) as a power source.

In FIG. 1, reference numeral 6 denotes an ECU, to which signals from the sensors 1, 2 and the switch 3 are input, and controls each section according to these signals. That is, the ECU 6
Exchanges signals with the engine control unit 4,
Outputs a fuel injection amount control command to perform engine output control including engine stop, exchanges signals with the motor control unit 5, and outputs a command to control motor drive and stop. .

Further, the ECU 6 determines whether or not the preceding vehicle has started decelerating from a change in the inter-vehicle distance from the preceding vehicle detected by the inter-vehicle distance sensor 1 while the vehicle is running on the gasoline engine. When it is determined that the vehicle has run, a function of switching from running by a gasoline engine to running by a motor is provided. This determination process corresponds to a determination unit, and the process of switching from traveling by a gasoline engine to traveling by a motor corresponds to a switching unit.

The ECU 6 learns from the output of the accelerator pedal opening sensor 2 the depressing operation of the accelerator pedal by the driver particularly at the time of starting, and from the output of the following distance sensor 1 and the brake lamp switch 3, A change in the inter-vehicle distance detected when the vehicle is stopped behind the vehicle is derived, and based on the derived result, it is determined whether the acceleration of the preceding vehicle is greater than a predetermined amount, and the learning result of the accelerator pedal depressing operation is determined. It is determined whether the degree of acceleration requested by the driver is large or not. When it is determined that the degree of acceleration of the preceding vehicle is larger than a predetermined amount and the degree of acceleration requested by the driver is large, the gasoline engine is driven in addition to the motor. And has a function of outputting a command to the engine control unit 4 and the motor control unit 5 to start the vehicle.

The learning process by the ECU 6 corresponds to a learning unit, the determination process corresponds to a determination unit, and the process of outputting a command to the engine control unit 4 and the motor control unit 5 corresponds to a start control unit.

Next, the operation will be described. First, the operation during running by the gasoline engine will be described with reference to the flowchart of FIG. 2. As shown in FIG. 2, the inter-vehicle distance to the preceding vehicle is detected by the inter-vehicle distance sensor 1 (step S1), and the determination unit is performed. The ECU 6 determines whether or not the preceding vehicle has started to decelerate from the change in the following distance (step S2). If the determination result is NO, the running state is maintained (step S3). Then, the process returns to step S1.

On the other hand, if the result of the determination in step S2 is YES, it can be determined that the preceding vehicle has clearly started decelerating. Therefore, a command to stop the engine is issued to the engine control unit 4 by the ECU 6 as a switching unit. At the same time
Commands are issued to the motor control unit 5 to drive the motor (step S4).
Further, under the control of the motor control unit 5, switching from traveling by the gasoline engine to traveling by the motor is performed, and regenerative braking is performed by the motor (step S5), and thereafter, the process returns to step S1.

Next, the operation in the case where the own vehicle is stopped behind the preceding vehicle at the time of waiting for a traffic light or the like will be described with reference to the flowchart of FIG.

First, an inter-vehicle distance from a preceding vehicle is detected by the inter-vehicle distance sensor 1 (step S11), and a determination is made by the ECU 6 as a determination unit based on a change in the inter-vehicle distance as to whether or not the preceding vehicle has started. Step S12) If the determination is NO, the process returns to Step S11. If the determination is YES, it is determined from the output of the brake lamp switch 3 whether or not the vehicle is stopped (Step S1).
3) If the determination result is NO, the determination in step S13 is repeated until the determination result becomes YES.

The result of the determination in step S13 is YE
In S, it is determined whether or not the degree of acceleration of the preceding vehicle is greater than a predetermined amount from the change in the inter-vehicle distance with the preceding vehicle (step S14). If the determination result is YES, the accelerator pedal opening sensor Based on the result of learning from the output of 2 that the driver depresses the accelerator pedal at the time of starting, it is determined whether or not the degree of acceleration required by the driver is large (step S15).

If the result of the determination in step S15 is YES, it can be determined that the degree of acceleration of the preceding vehicle is greater than the predetermined amount and the degree of acceleration required by the driver is greater.
The engine control unit 4 is controlled by the ECU 6 as a start control unit.
Then, a command is issued to the motor control unit 5 to drive both the gasoline engine and the motor (step S16), and the engine control unit 4 and the motor control unit 5 based on these commands are driven.
With the control of (1), the gasoline engine is driven in addition to the motor, and the starting acceleration is performed by both the gasoline engine and the motor (step S17), and the operation is thereafter terminated. The accelerator depression amount by the driver with respect to the acceleration of the preceding vehicle at the start is also learned.

Incidentally, step S14 and step S14
If the determination result in No. 15 is NO, since a particularly large acceleration is not required to drive the gasoline engine in addition to the motor, a command is issued to the motor control unit 5 to drive only the motor (step S18). Under the control of the motor control unit 5 based on the command, the starting acceleration is performed by the motor having the large generated torque (step S19), and the operation is thereafter terminated.

Therefore, according to the above-described embodiment, when it is determined that the preceding vehicle has started decelerating from the change in the following distance from the preceding vehicle by the following distance sensor while the vehicle is running on the gasoline engine, the gasoline engine may be used. Since it is switched from running by the engine to running by the motor, braking can be performed using regenerative braking by the motor,
By effectively regenerating the energy generated by the regenerative braking to the power supply side of the motor, it is possible to further reduce gasoline consumption and improve fuel efficiency.

Further, when the vehicle is stopped behind the preceding vehicle, it is determined from the change in the inter-vehicle distance to the preceding vehicle that the acceleration of the preceding vehicle is greater than a predetermined amount and that the acceleration required by the driver is greater. In this case, the gasoline engine is driven in addition to the motor to start the vehicle, so that the vehicle can be started with the acceleration required by the driver at the time of starting, and the response at the time of starting can be improved.

In the above-described embodiment, the regenerative braking by the motor during the running by the gasoline engine,
A case has been described where both the motor and the gasoline engine can be started and accelerated at the time of starting while the own vehicle is stopped behind the preceding vehicle, but it is also possible to configure so that only one of the former and the latter can be performed. Of course it is good.

The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the gist of the present invention.

[0032]

As described above, according to the first aspect of the present invention, during running by the gasoline engine, the running can be switched from running by the gasoline engine to running by the motor. Hybrid vehicle as a low-emission vehicle by reducing gasoline consumption and improving fuel efficiency by effectively regenerating the energy generated by regenerative braking to the power supply side of the motor. It is possible to further improve the function.

According to the second aspect of the present invention, when the vehicle is stopped behind the preceding vehicle, the gasoline engine is driven in addition to the motor if necessary. Can be started with the required acceleration, and it is possible to improve the response of the hybrid vehicle when starting.

According to the third aspect of the present invention, the fuel consumption can be improved by reducing the gasoline consumption by regenerative braking of the motor, and the vehicle can be started according to the acceleration required by the driver. Thus, the response at the time of starting can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a flowchart illustrating an operation of the embodiment.

FIG. 3 is a flowchart illustrating an operation of the embodiment.

[Explanation of symbols]

Reference Signs List 1 inter-vehicle distance sensor 2 accelerator pedal opening sensor 6 ECU (judgment unit, switching unit, learning unit, judgment unit, start control unit)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 45/00 340 F02D 45/00 340C G08G 1/16 G08G 1/16 E (72) Inventor Kenichi Yamada Osaka 2-1, 1-1 Taoyuan, Ikeda-shi, Fukushima Daihatsu Industry Co., Ltd. (72) Inventor Yasuhisa Hiroshima 2-1-1, Taoyuan, Ikeda-shi, Osaka F-term in Daihatsu Kogyo Co., Ltd. 3G084 BA13 CA06 CA07 DA02 DA05 EA11 EB17 FA04 FA05 FA10 3G093 AA07 BA15 BA19 CB01 CB07 DA06 DB05 DB15 DB16 DB21 EA05 EB08 FA09 FA11 5H115 PA12 PG04 PI11 PU02 PU23 PU27 QE10 QI04 RE01 RE03 RE05 SE04 SE05 TO06 TO21 TO23 5H180 AA01 CC

Claims (3)

[Claims] 1. A hybrid vehicle that combines a gasoline engine and a motor as power sources and is driven by the motor at low speed and the gasoline engine at high speed. A determination unit that determines whether or not the preceding vehicle has started decelerating based on a change in the following distance from the preceding vehicle detected by the following distance sensor while the vehicle is running with the gasoline engine; and A switching unit that switches from running by the gasoline engine to running by the motor when it is determined that the vehicle has started decelerating. 2. A hybrid vehicle that combines a gasoline engine and a motor as power sources and is driven by the motor at low speed and the gasoline engine at high speed. A learning unit that learns the accelerator pedal depressing operation by the driver at the time of starting, and a change in the following distance between the preceding vehicle detected by the following distance sensor when the own vehicle is stopped behind the stopped preceding vehicle. Whether the acceleration of the preceding vehicle is greater than a predetermined amount,
And a determining unit that determines whether the degree of acceleration requested by the driver is large based on the learning result of the learning unit. The determining unit determines that the degree of acceleration of the preceding vehicle is larger than a predetermined amount, and the driver requests. A hybrid vehicle comprising: a start control unit that starts by driving the gasoline engine in addition to the motor when it is determined that the degree of acceleration is large. 3. A learning unit for learning a stepping operation of an accelerator pedal by a driver at the time of starting, and a distance between the preceding vehicle detected by the inter-vehicle distance sensor behind the stopped preceding vehicle while the own vehicle is stopped. A determination unit that determines whether the acceleration level of the preceding vehicle is greater than a predetermined amount based on a change in the distance, and whether the acceleration level requested by the driver is large based on the learning result of the learning unit; A start control unit that starts the vehicle by driving the gasoline engine in addition to the motor when the degree of acceleration of the vehicle is determined to be larger than the predetermined amount and the degree of acceleration requested by the driver is determined to be large. The hybrid vehicle according to claim 1, wherein: