JP2678909B2 - Rotational speed control device for four-wheel drive vehicle - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotational speed control device for a four-wheel drive vehicle, and particularly to a first internal combustion engine and a first internal combustion engine except during execution of torque control during cornering of the four-wheel drive vehicle. When the engine speed of each of the two internal combustion engines is equal to or higher than a predetermined speed and the engine speed of the first internal combustion engine and the engine speed of the second internal combustion engine are different from each other, these engine speeds are made substantially the same. The present invention relates to a rotation speed control device for a four-wheel drive vehicle that performs fuel cut control to suppress unnecessary wheel spin and restore grip early to improve control efficiency of a four-wheel drive vehicle.

[Conventional technology]

BACKGROUND OF THE INVENTION In a vehicle, particularly a vehicle used for racing, four wheels equipped with a first internal combustion engine for driving front wheels for driving front wheels and a second internal combustion engine for driving rear wheels for driving rear wheels, so-called twin engine There is a driving car. In a four-wheel drive vehicle equipped with these first and second internal combustion engines, if one internal combustion engine fails, the other internal combustion engine can reach a predetermined location and both internal combustion engines can accelerate the vehicle. And there are advantages such as increasing the output of the engine.

Further, as such a four-wheel drive vehicle, for example,
Some are disclosed in Japanese Patent Laid-Open No. 61-174338. In the one disclosed in this publication, the driving state of a four-wheel drive vehicle is detected by a driving state detecting means composed of respective sensors, and the driving control means operates the first or second output controlling means in accordance with the driving state detecting means. It is operated to control the output of the first or second internal combustion engine, respectively.

[Problems to be solved by the invention]

By the way, in the conventional four-wheel drive vehicle, the engine speeds of the first internal combustion engine for driving the front wheels for driving the front wheels and the second internal combustion engine for driving the rear wheels for driving the rear wheels are substantially the same. Although it is set, a large difference occurs between the engine speed of the first internal combustion engine and the engine speed of the second internal combustion engine in operating conditions such as start acceleration and jumping.

For this reason, wheel spin occurs on the front wheels due to the difference in engine speed, which requires a large amount of time for grip recovery, which adversely affects electronic control of a four-wheel drive vehicle and lowers control efficiency. .

[Object of the invention]

Therefore, an object of the present invention is to provide steering means for steering a four-wheel drive vehicle and a steering sensor for detecting the operating state of the steering means in order to eliminate the above-mentioned inconvenience, and to detect from this steering sensor. A first internal combustion engine and a second internal combustion engine except when a torque control is being performed during cornering of the four-wheel drive vehicle by inputting a signal and the respective engine speeds of the first internal combustion engine and the second internal combustion engine. When the respective engine speeds of the above are equal to or higher than the predetermined engine speed and the engine speed of the first internal combustion engine and the engine speed of the second internal combustion engine are different, these engine speeds should be made substantially the same by the control means. Fuel cut control suppresses unnecessary wheel spin, restores grip early, and can prevent the influence on electronic control of a four-wheel drive vehicle. The in realizing the speed control system for four-wheel drive vehicle capable of improving.

[Means for solving the problem]

In order to achieve this object, the present invention provides a four-wheel drive vehicle equipped with a first internal combustion engine for driving front wheels and a second internal combustion engine for driving rear wheels, and a steering system for steering the four-wheel drive vehicle. Means and a steering sensor for detecting an operating state of the steering means, and by inputting a detection signal from the steering sensor and inputting the engine speeds of the first internal combustion engine and the second internal combustion engine, respectively. The respective engine speeds of the first internal combustion engine and the second internal combustion engine are equal to or higher than a predetermined rotational speed except during execution of torque control during cornering of the four-wheel drive vehicle, and the engine speed of the first internal combustion engine and the second internal combustion engine. When the engine speed of the engine is different from that of the engine, a control means is provided for performing fuel cut control so that these engine speeds are substantially the same.

[Action]

With the above-described configuration, the engine speeds of the first internal combustion engine and the second internal combustion engine except when torque control is being performed during cornering of the four-wheel drive vehicle are equal to or higher than a predetermined rotational speed and the first internal combustion engine is operated. Engine speed and second
When the engine speed of the internal combustion engine differs from that of the internal combustion engine, fuel cut control is performed by the control means so that the engine speeds of the first internal combustion engine and the second internal combustion engine are substantially the same, and unnecessary wheel spin is suppressed. At the same time, the grip is restored early, the influence on the electronic control of the four-wheel drive vehicle is prevented, and the control efficiency is improved.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 to 5 show an embodiment of the present invention. In FIG. 2, 2 is a four-wheel drive vehicle (hereinafter simply referred to as “vehicle”), 4 and 4 are front wheels, 6 and 6 are rear wheels, 8 is steering means, and 10 is an accelerator pedal. The vehicle 2 is equipped with a first internal combustion engine 12 for driving front wheels, which drives front wheels 4, 4, and a second internal combustion engine 14 for driving rear wheels, which drives rear wheels 6, 6.

The first internal combustion engine 12 is provided with a first transmission 16 and
A front wheel shaft 18 connected to the front wheels 4 and 4 is connected to the transmission 16. Further, the first internal combustion engine 12 is provided with a first throttle section 20 and a first ignition mechanism 22.

On the other hand, the second internal combustion engine 14 is provided with a second transmission 24, and the second transmission 24 has rear wheel shafts 26 connected to the rear wheels 6, 6.
Are linked. Further, the second internal combustion engine 14 is provided with a second throttle portion 28 and a second ignition mechanism 30.

The steering means 8 includes a steering wheel 32 and a steering shaft 34 connected to the steering wheel 32.
And a steering gear mechanism and a link mechanism (not shown).

The first internal combustion engine 12 and the second internal combustion engine 14 are drive-controlled by a control means 36 which detects the engine operating states of the first and second internal combustion engines 12 and 14 and outputs a control signal.

The control means 36 includes a first control unit 38 that drives the first internal combustion engine 12 and a second control unit 40 that drives the second internal combustion engine 14, and the first internal combustion engine 12 and the second internal combustion engine 12 of the vehicle 2 are described. The respective engine speeds N _F and N _R of the engine 14 are input to the first internal combustion engine.
When the engine speed N _{F of} 12 and the engine speed N _R of the second internal combustion engine 14 are different, it has a function of controlling these engine speeds N _F and N _R to be substantially the same.

That is, the first control unit 38 is made to input the engine speed N _F of the first internal combustion engine 12 and the engine speed N _R of the second internal combustion engine 14, respectively, and the execution signal for torque control of the first internal combustion engine 12 is inputted. And the engine speed N _F of the first internal combustion engine 12 and the engine speed N _{R of} the second internal combustion engine 14, respectively, and the torque control of the second internal combustion engine 14 Input the execution signal. Then, it controls so as to engine speed N _F, atmospheric become one of engine speed the engine rotational speed decreases the N _F of N _R, an N _R substantially the same.

In this embodiment, the fuel cut control of the first internal combustion engine 12 or the fuel cut control of the second internal combustion engine 14 is performed in order to make the engine speeds N _F and N _R substantially the same.

Further, when the difference between the engine speeds N _F and N _R is determined, the control means 36 presets two kinds of engine speed control widths n _F1 , n _F2 and n _R1 , n _R2 in front and rear, respectively. _However , by satisfying the inequalities N _F > N _R + n _F1 or N _R > N _F + n _R1 by these engine speed control widths n _F1 , n _F2 and n _R1 , n _R2 , the engine speed N _F , N _The control is performed so that _Rs are substantially the same. This engine speed N _F ,
In the control in which N _R is substantially the same, the control operation is canceled and the normal control is restored by satisfying the inequalities N _F ≦ N _R + n _F2 or N _R ≦ N _F + n _R2 . At this time, the engine speed control widths n _F1 , n _F2 and n _R1 , n _R2 are set to n _F1 , n _R1 = 1000
Set to rpm and n _F2 , n _R2 = 600 rpm.

Further, the control by the control means 36 to make the engine speeds N _F and N _R substantially the same is set so as not to operate during torque control during cornering of the vehicle, and is set to a certain engine speed or more. It is set to operate when it becomes.

The steering shaft 34 of the steering means 8 is provided with a steering sensor (also referred to as a "steering angle amount sensor") 42 including a variable resistor or the like for detecting the rotating state of the steering shaft 34 as an operating state of the steering means 8. The steering sensor 42 is provided and communicated to the control means 36.

A first accelerator wire 46 connected to the first throttle section 20 and a second accelerator wire 48 connected to the second throttle section 28 are connected to the accelerator pedal 10 via a main accelerator wire 44.

Further, the first ignition mechanism 22 and the first control unit 38 are connected by the first wiring harness 50, and the second ignition mechanism 30 and the second control unit 40 are connected to the second wiring harness.
I am contacted by 52.

As shown in FIG. 3, the first control unit 38 includes an intake air amount sensor 54 for detecting the intake air amount into the first internal combustion engine 12 in order to detect the operating state of the first internal combustion engine 12. A throttle sensor 56 that detects the opening of a throttle valve (not shown) of the first throttle unit 20, a cooling water temperature sensor 58 that detects the cooling water temperature of the first internal combustion engine 12, and an O ₂ sensor that detects the exhaust gas concentration. 60, a first crank angle sensor 62 for detecting the engine speed of the first internal combustion engine 12, a second crank angle sensor 64 for detecting the engine speed of the second internal combustion engine 14, and the steering sensor 42. I am in touch.

On the other hand, although not shown, the second control unit 40 includes a first control unit.
Similarly to 38, to detect the operating state of the second internal combustion engine 14,
An intake air amount sensor 54 for detecting the amount of intake air to the second internal combustion engine 14, a throttle sensor 56 for detecting the opening of a throttle valve (not shown) of the second throttle portion 28, and the second internal combustion engine 14 A cooling water temperature sensor 58 for detecting the cooling water temperature of the engine, an O ₂ sensor 60 for detecting the exhaust gas concentration, a first crank angle sensor 62 for detecting the engine speed of the first internal combustion engine 12, and a second
A second crank angle sensor 64 for detecting the engine speed of the internal combustion engine 14 and the steering sensor 42 are in communication with each other.

Further, the first control unit 38 communicates with the intake air amount sensor 54, the throttle sensor 56, the cooling water temperature sensor 58, the O ₂ sensor 60, the first crank angle sensor 62, the second crank angle sensor 64, and the steering sensor 42. The first input / output section 66, the fuel injection valve 68, the EGR solenoid valve 70, the ignition coil 72 of the first ignition mechanism 22, and the boost pressure control solenoid valve 74.
And throttle valve control motor (eg stepping motor) 76
A second input / output unit 78 that communicates with, a CPU (central processing unit) 80 that communicates with the first and second input / output units 66 and 78, and this CPU
It comprises a ROM (fixed storage unit) 82 for contacting 80, and a RAM (constant speed call storage unit) 84 for contacting this ROM 82. Further, the battery 88 communicates with the first control unit 38 via the key switch 86.

On the other hand, although not shown, the second control unit 40 does not include the first control unit 38.
Similarly, the intake air amount sensor 54, the throttle sensor 56, the cooling water temperature sensor 58, the O ₂ sensor 60, and the first crank angle sensor
62, the second crank angle sensor 64, the first input / output unit 66 communicating with the steering sensor 42, the fuel injection valve 68, the EGR solenoid valve 70, and the ignition coil 72 of the second ignition mechanism 30.
And a second input / output unit 78 that communicates with the boost pressure control solenoid valve 74 and the throttle valve control motor (for example, stepping motor) 76, and communicates with the first and second input / output units 66 and 78.
CPU (Central Processing Unit) 80, ROM that contacts this CPU 80
It comprises a (fixed storage unit) 82 and a RAM (constant speed calling storage unit) 84 which communicates with the ROM 82.

Further, this embodiment will be described in detail. As shown in FIG. 4, the CPU 80 of the first controller 38 includes at least first and second crank angle sensors 62 and 64 and an air flow meter 90 as an intake air amount sensor. And the cooling water temperature sensor 58 are connected.

The operation will be described with reference to the flowchart for controlling the rotation speed of the vehicle 2 in FIG.

The engine speed N _F of the first internal combustion engine 12 is set to the first and second
The control units 38, 40 are caused to input the engine speed N _R of the second internal combustion engine 14 to the first and second control units 38, 40. Torque control execution signals are also input to the first and second control units 38 and 40, respectively.

The rotation speed control of the vehicle 2 is performed simultaneously by the first and second control units 38 and 40. First, the first control unit 38
The control by will be described.

The first control unit 38 determines that the engine speed N _F of the first internal combustion engine 12 is equal to the engine speed N _R of the second internal combustion engine 14 and the engine speed control range n as in the inequality N _F > N _R + n _F1.
A judgment (100) is made as to whether or not the sum with _F1 is exceeded, and if this judgment (100) is NO, the control shifts to normal control (102) in which engine speed control is not carried out, and the judgment (100) is repeated. At the same time, if the determination (100) is YES, it is determined (104) whether or not torque control is being performed during cornering.

If this judgment (104) is YES, normal control (10
In step 2), the determination (100) is repeated, and in the case of NO, it is determined (106) whether the engine speed is equal to or higher than a predetermined speed, that is, the torque band set speed.

If this judgment (106) is NO, normal control (102)
And the determination (100) is repeated, and if YES, the front speed control (108), that is, the engine speed N _F of the first internal combustion engine 12 is the engine speed N _R of the second internal combustion engine 14. Higher than the first internal combustion engine 12
Engine speed N _F of the second internal combustion engine 14
Fuel cut control is performed so that it is approximately the same as N _R.

Further, after the front speed control (108), it is determined whether or not torque control during cornering is being executed (11
0) is performed, and if YES, the front speed control is released, the normal control (112) is restored, and the above normal control (102) is entered. If NO, the engine speed is the predetermined speed. That is, it is judged (114) whether or not the torque band is equal to or higher than the set rotational speed.

When this judgment (114) is NO, the front speed control is released, the normal control (112) is restored, the above normal control (102) is entered, and the judgment (100) is repeated. In the inequality N _F ≦ N _R + n _F2 , the engine speed N _F of the first internal combustion engine 12 is the engine speed N _R of the second internal combustion engine 14 and the engine speed control range n
_It is judged whether it is less than or equal to the sum of _F2 (116).

If the determination (116) is NO, the process returns to the front speed control (108), and if the result is YES, the front speed control is released and the normal control (112) is resumed. Move to (102) and judge (100)
repeat.

 Next, the control by the second controller 40 will be described.

Like the above-described first control unit 38, the second control unit 40 determines that the engine speed N _R of the second internal combustion engine 14 is equal to the engine speed of the first internal combustion engine 12 as in the inequality N _R > N _F + n _R1. Number N _F and engine speed control range n
A judgment (120) is made as to whether or not the sum of _R1 and _R1 is exceeded, and if this judgment (120) is NO, the routine shifts to normal control (102) in which engine speed control is not executed, and judgment (120) is repeated. At the same time, if the determination (120) is YES, it is determined (124) whether or not torque control is being performed during cornering.

If this judgment (124) is YES, normal control (10
The process proceeds to 2) and the determination (120) is repeated, and if NO, it is determined (126) whether the engine speed is equal to or higher than a predetermined speed, that is, the torque band set speed.

If this judgment (126) is NO, normal control (102)
And the determination (120) is repeated, and if YES, the rear speed control (128), that is, the engine speed N _R of the second internal combustion engine 14 is the engine speed of the first internal combustion engine 12.
Is determined to be higher than N _F, performs fuel cut control in order to the engine rotational speed N _R of the second internal combustion engine 14 and the engine rotational speed N _F and substantially the same first internal combustion engine 12.

Also, after the rear speed control (128), it is judged whether the torque control during cornering is being executed (130). If YES, the rear speed control is released and the normal control (112) is restored. Let the above normal control (102)
If NO, the engine speed is a predetermined speed,
In other words, it is judged whether the torque band is equal to or higher than the set speed
Do 4).

If this judgment (134) is NO, the rear rotation speed control is released, the normal control (112) is restored, the above normal control (102) is entered, and the judgment (120) is repeated. In the inequality N _R ≦ N _F + n _R2 , the engine speed N _R of the second internal combustion engine 14 is the engine speed N _F of the first internal combustion engine 12 and the engine speed control range n
_It is judged whether the sum is less than or equal to _R2 (136).

Then, when the determination (136) is NO, the control returns to the rear rotation speed control (128), and when the determination (YES) is YES, the rear rotation speed control is released and the normal control (112) is resumed. The process shifts to (102) and the determination (120) is repeated.

In the rotational speed control of the vehicle 2 described above, as shown in FIG. 5, the probability of causing wheel spin on the front wheel side of the vehicle 2 is generally high, and a machine for controlling the engine rotational speed of the first internal combustion engine 12 is generally used. There are many.

As a result, the engine speeds N _F and N _{R of} the first internal combustion engine 12 and the second internal combustion engine 14 except when the torque control is being performed during cornering of the vehicle 2 are equal to or higher than a predetermined speed, that is, the torque band set speed. And the engine speed N _F of the first internal combustion engine 12 and the engine speed N _R of the second internal combustion engine 14
, The engine speed of one of the internal combustion engines is reduced by the fuel cut control, and the engine speeds of the first internal combustion engine 12 and the second internal combustion engine 14 are reduced.
By controlling N _F and N _R to be approximately the same, unnecessary wheel spin can be suppressed, the grip can be recovered early, the influence on the electronic control of the vehicle 2 can be prevented, and control efficiency is improved. Can be made.

Further, the engine speeds N _F and N _R of the first and second internal combustion engines 12 and 14 are input to the first and second control units 38 and 40, respectively, to electrically control the speed of the vehicle 2. By doing so, the number of mechanical parts does not increase, the configuration does not become complicated, and the cost can be kept low.

Further, by using the first and second control units 38, 40, the engine speed control range and the first,
It is possible to set the operating speed range of the second control units 38 and 40 or any other numerical value, and it is possible to perform the speed control as desired, which is practically advantageous.

〔The invention's effect〕

As described in detail above, according to the present invention, the steering means for steering the four-wheel drive vehicle is provided, the steering sensor for detecting the operation state of the steering means is provided, and the detection signal from the steering sensor is input. In addition, the engine speeds of the first internal combustion engine and the second internal combustion engine are input, and the respective engine speeds of the first internal combustion engine and the second internal combustion engine are excluded except when torque control is being performed during cornering of the four-wheel drive vehicle. When the engine speed is equal to or higher than a predetermined engine speed and the engine speed of the first internal combustion engine and the engine speed of the second internal combustion engine are different from each other, a control means for performing fuel cut control to make these engine speeds substantially the same is provided. Since it is provided, the engine speeds of the first internal combustion engine and the second internal combustion engine are equal to or higher than the predetermined speed, except during execution of torque control during cornering of the four-wheel drive vehicle. And when the engine rotational speed of the first internal combustion engine and the engine rotational speed of the second internal combustion engine are different,
The fuel cut control is performed by the control means so that these engine speeds are substantially equal to each other, unnecessary wheel spin can be suppressed, and the grip can be recovered at an early stage, which affects the electronic control of the four-wheel drive vehicle. And the control efficiency can be improved. Further, the engine speeds of the first and second internal combustion engines are respectively input to the control means to electrically control the rotational speed of the four-wheel drive vehicle, so that there is no increase in mechanical parts, and the structure is improved. However, the cost can be kept low without complication. Further, by using the control means when controlling the rotation speed of the four-wheel drive vehicle,
The program allows arbitrary setting of numerical values, and the rotation speed can be controlled as desired, which is practically advantageous.

[Brief description of the drawings]

1 to 5 show an embodiment of the present invention, FIG. 1 is a flowchart for controlling the rotational speed of a vehicle, FIG. 2 is a schematic diagram of the vehicle,
FIG. 3 is a circuit diagram of the control means, FIG. 4 is a specific circuit diagram of the control means, and FIG. 5 is a diagram showing a difference in engine speed between the first internal combustion engine and the second internal combustion engine. . In the figure, 2 is a vehicle, 4 and 4 are front wheels, 6 and 6 are rear wheels, 12 is a first internal combustion engine, 14 is a second internal combustion engine, 36 is control means, 38 is a first control unit, and 40 is a first control unit. 2 control unit, 62 first crank angle sensor, 64 second crank angle sensor, 66 first input / output unit, 78 second input / output unit, 80 CPU (central processing unit), 82 ROM ( (Fixed storage unit), 84 is RAM (constant speed calling storage unit), N _F , N _R are engine speeds, n _F1 , n _F2 and
n _R1 and n _R2 are engine speed control widths.

Claims (1)

(57) [Claims] 1. A four-wheel drive vehicle equipped with a first internal combustion engine for driving front wheels and a second internal combustion engine for driving rear wheels.
Steering means for steering a wheel drive vehicle is provided, a steering sensor for detecting an operating state of the steering means is provided, and a detection signal from the steering sensor is input and the first internal combustion engine and the second internal combustion engine are provided. The respective engine speeds of the first internal combustion engine and the second internal combustion engine are equal to or higher than a predetermined rotational speed except during execution of torque control during cornering of the four-wheel drive vehicle. When the engine speed of the internal combustion engine and the engine speed of the second internal combustion engine are different, a four-wheel drive is provided with control means for performing fuel cut control so that these engine speeds become substantially the same. Vehicle speed control device.