JPH054534A - Vehicle control device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a vehicle control device capable of sufficiently exhibiting the functions of both the differential limiting device and the anti-skid brake device. [Structure] A differential limiting device that performs differential limiting with an inter-axle differential in a locked state, and an anti-skid brake device that detects a skid state of each wheel and controls the braking force of each wheel according to the skid state. In the control device of the vehicle, the differential limiting device reduces the differential limiting force of the differential limiting device by setting the inter-axle differential to the intermediate lock state when the brake is activated, and the differential limiting that unlocks the inter-axle differential when the anti-skid brake device is activated It is characterized by having a control means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a vehicle, and more particularly to a control device for a four-wheel drive vehicle equipped with a differential limiting device and an antiskid brake device.

[0002]

2. Description of the Related Art In recent years, a center differential for transmitting a driving force of an engine to a front wheel side and a rear wheel side, and a front and rear drive device having a differential lock device for locking and unlocking the differential are provided, 2. Description of the Related Art A vehicle equipped with a braking device having an anti-skid braking device that controls a rotational braking force according to a wheel slip condition has been developed. In such a vehicle, the differential lock device unlocks the differential to absorb the difference in rotation between the front wheels and the rear wheels to enable normal running of the vehicle, and to lock the front wheels or the rear wheels. It makes it easier for vehicles that have entered the muddy area to escape and to run on snowy roads. On the other hand, the anti-skid brake device detects the skid state of each wheel and controls the braking force of each wheel according to the skid state to maximize the braking force of the vehicle on muddy, snowy roads, etc. In addition, the directional stability of the vehicle is ensured.

In such a vehicle, in order to fully exhibit the function of the anti-skid brake device, the differential is controlled to the unlocked condition on condition that the brake pedal is depressed, and there is a device disclosed in Japanese Patent Laid-Open Publication No. Sho. It is disclosed in JP 61-287824.

[0004]

However, in the above-described conventional vehicle, since the differential is unlocked immediately after the brake pedal is depressed, even if the anti-skid brake device is activated, each wheel is It is easy to be locked, and the vehicle is likely to fall into an unstable state. Therefore, considering the stability of the vehicle, it is desirable that the differential be in a locked state until the anti-skid brake device is activated even when the brake pedal is depressed.

Therefore, the present invention has been made in order to solve the above-mentioned drawbacks of the prior art, and is a vehicle control device capable of sufficiently exhibiting the functions of both the differential limiting device and the anti-skid brake device. Is intended to provide.

[0006]

In order to achieve the above object, the present invention provides a differential limiting device for performing differential limiting with an inter-axle differential in a locked state and a skid state of each wheel by detecting the skid state. In a vehicle control device having an anti-skid brake device for controlling the braking force of each wheel according to the state, a differential limiting force of the differential limiting device is lowered while an inter-axle differential is in an intermediate locked state when the brake is actuated. It is characterized by having differential limiting control means for unlocking the inter-axle differential when the anti-skid brake device is activated.

In the present invention constructed as described above,
When the brakes are applied, the inter-axle differential is placed in the intermediate lock state to reduce the differential limiting force of the differential limiting device, and when the anti-skid brake device is activated, the inter-axle differential is unlocked. Both functions of the device can be fully exhibited, and the responsiveness of the anti-skid brake device can be improved.

Further, the present invention is directed to a differential limiting device for performing differential limiting with the inter-axle differential and the inter-wheel differential being in a locked state, and the skid state of each wheel to be detected and the braking force of each wheel depending on the skid state. In a control device for a vehicle having an anti-skid brake device for controlling a vehicle, a first differential limiting means provided on an inter-axle differential and a second differential limiting means provided on an inter-wheel differential.
Differential limiting means, a first mode in which the first differential limiting means and the second differential limiting means are automatically controlled in accordance with operating states, respectively, and the first differential limiting means is in a completely locked state. At the same time, a mode setting means for setting a second mode for automatically controlling the second differential limiting means according to an operating state, a switching means for switching between the first mode and the second mode, and a brake in the first mode. When the brake is activated, both the first differential limiting means and the second differential limiting means are unlocked, and when the brake is activated in the second mode, the first differential limiting means is set to the intermediate locked state. The second differential limiting means is in an unlocked state, and when the antiskid brake device is activated, the first differential limiting means is in an unlocked state.

In the present invention constructed as described above,
When the brake operates in the first mode, both the first differential limiting means and the second differential limiting means are unlocked,
When the brake operates in the second mode, the first differential limiting device is set to the intermediate locked state, the second differential limiting device is unlocked, and when the anti-skid brake device is activated, the first differential is set. Since the limiting means is in the unlocked state, it is possible to fully exert the functions of both the differential limiting device and the anti-skid brake device,
Further, the responsiveness of the anti-skid brake device can be particularly improved in the first mode in which the driver is not aware of the complete lock state.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram showing an overall configuration of a vehicle control device of the present invention. First, the power transmission system of the vehicle shown in FIG. 1 will be described. 10 is an engine, and a transmission 11 is connected to the engine 10.
A transfer 12 is connected to the transmission 11. This transfer 12 has an engine 1
A front propeller shaft 13 for transmitting the output from 0 to the front wheel side and a rear propeller shaft 14 for transmitting the output to the rear wheel side are respectively connected. A front wheel 16 is connected to the front propeller shaft 13 via a front axle 15. A rear wheel 18 is connected to the rear propeller shaft 14 via a rear axle 17. In addition, the transfer 12
Differential 20 (hereinafter referred to as center differential),
The front axle 15 is provided with a front differential 21 (hereinafter referred to as front differential), and the rear axle 17 is provided with a rear differential 22 (hereinafter referred to as rear differential).

A wheel speed sensor 30 for detecting the wheel speed of each wheel is attached to each front wheel 16 and each rear wheel 18. Reference numeral 31 is a brake switch, and the brake switch 31 detects ON / OFF of the brake. Reference numeral 32 denotes a throttle sensor, which detects the throttle opening of the engine 10.

Reference numeral 40 denotes an engine control unit, and the throttle opening is input from the throttle sensor 32 to the engine control unit 40. Reference numeral 41 is a control unit for an anti-skid brake device (hereinafter referred to as an ABS control unit), and each wheel speed is input from the wheel speed sensor 30 to the ABS control unit 41. Reference numeral 43 denotes a differential control unit. The differential control unit 43 is connected with a manual switch 44 and a battery 45 for selecting a diff lock mode to be described later. The differential control unit 43 includes a throttle opening from the throttle sensor 32, a brake signal from the brake switch 31, an ABS signal from the ABS control unit 41 indicating whether the anti-skid brake device is in operation, and each wheel. The wheel speed and the mode signal are input from the manual switch 44, respectively. Based on each of these input values, the differential control unit 43
To the center differential 20, the front differential 21 to the front differential current, and the rear differential 22 to the rear differential current. Based on these current values, the center differential 20, the front differential 21, and the rear differential 22 are in the unlocked state, the intermediate differential state, and the intermediate differential state. Locked and completely locked. Control unit 4 for differential
3 to ABS control unit 41, ABS
A prohibition signal is output.

FIG. 2 is a sectional view showing an electromagnetic multi-plate clutch provided on the center differential. The center differential 20 is provided with an electromagnetic multi-plate clutch 50, and the electromagnetic multi-plate clutch 50 brings the center differential 20 into an unlocked state, an intermediate locked state, and a completely locked state. The electromagnetic multi-plate clutch 50 may be of any type as long as it can limit the differential between the front propeller shaft 13 and the rear propeller shaft 14. An example thereof is shown in FIG. In FIG. 2, the electromagnetic multi-plate clutch 50 is composed of a clutch plate 51 composed of a plurality of inner discs and an outer disc, and an actuator 52 for generating a pressing force on the clutch plate 51. 53 is a bearing,
Reference numeral 54 is a transmission member that is transmission-connected to one propeller shaft, and 55 is a transmission member that is transmission-connected to the other propeller shaft. The actuator 52 uses the magnetic force generated when a current flows through the solenoid 56 to cause the armature 5 to move.
7 is configured to press the clutch plate 51.
In this electromagnetic multi-plate clutch 50, the solenoid 56
Is proportional to the pressing force for frictionally engaging the clutch plate 51, that is, the torque generated by the electromagnetic multi-plate clutch 50, the operating speed of the center differential 20 can be continuously changed by increasing or decreasing the current. it can.

The front differential 21 and the rear differential 22 are also provided with an electromagnetic multi-plate clutch, but the description thereof is omitted because it has the same structure as that shown in FIG. Next, the control contents in each mode selected by the manual switch 44 will be described with reference to Table 1.

[0015]

[Table 1]

As shown in Table 1, in the "AUTO (A mode)" of the manual switch 44, the front differential 21 is in the unlocked state, and the center differential 20 and the rear differential 22 are in the automatic mode control. "C (C mode)"
In the above, the front differential 21 is unlocked, the center differential 20 is completely locked, and the rear differential 22 is in automatic mode control. In "R (R mode)", the front differential 21 is unlocked, and the center differential 20 and the rear differential 22 are completely locked. In "F (F mode)", the front differential 21 and the center differential 20
Also, all of the rear differential 22 are completely locked. Here, If is the front differential current, Ic is the center differential current, Ir is the rear differential current, and the numerical values are the current values thereof. The electromagnetic multiple disc clutches provided in each differential are provided with the differential current of these values. By being supplied, each differential is brought into a completely locked state.

Each of these modes is arbitrarily selected by the driver. In A mode, front differential 2
Since No. 1 is in the unlocked state, it has little influence on the drivability and is excellent in operability, and is suitable for on-road traveling on a normal road such as an urban area. On the other hand, "F mode"
In, since the front differential 21, the center differential 20, and the rear differential 22 are all completely locked,
Operability is reduced, but driveability is excellent, making it suitable for off-road traveling on rough roads. The “C mode” and the “R mode” have characteristics between them and are selected according to the driver's preference.

Next, the control content of the differential control unit 43 will be described with reference to FIGS. In these figures, the symbol P indicates each step in the flowchart. FIG. 3 is a flowchart showing a vehicle body speed calculation routine in the "A mode" automatic mode control. As shown in FIG. 3, at P10, the wheel speeds Nfr, Nfl, Nrr, Nrl are input. here,
Nfr represents the wheel speed of the right front wheel, Nfl represents the wheel speed of the left front wheel, Nrr represents the wheel speed of the right rear wheel, and Nrl represents the wheel speed of the left rear wheel. Next, at P11, these wheel speeds Nfr,
The minimum value of Nfl, Nrr, and Nrl is defined as the vehicle body speed Vsp.

FIG. 4 is a flow chart showing a center differential differential rotation speed calculation routine in the automatic mode control of the "A mode". As shown in FIG. 4, the wheel speeds Nfr, Nfl, Nrr, and Nrl are input at P20. Then P21
At, the center differential differential rotation speed ΔNc, which is the rotation difference, is obtained. FIG. 5 is a flowchart showing a rear differential differential rotation speed calculation routine in the automatic mode control of the “A mode”. As shown in FIG. 5, at P30, the wheel speeds Nrr and Nrl of the rear wheels are input. Next, at P31, the rear differential differential rotation speed ΔNr is obtained.

FIG. 6 is a flow chart showing a center diff current setting routine in the automatic mode control of the "A mode". As shown in FIG. 6, at P40, the center differential current Ic is set. This center differential current Ic
Is calculated from the center differential differential rotation speed ΔNc and the throttle opening TVO. FIG. 7 is a diagram showing the relationship between the current value I ₁ and the center differential differential rotation speed ΔNc, and FIG. 8 is a diagram showing the relationship between the current value I ₂ and the throttle opening TVO. That is, when either the center differential differential rotation speed ΔNc or the throttle opening TVO reaches the maximum current value Imax, the center differential current Ic is set to “Ic = Imax”. When both the center differential differential rotation speed ΔNc and the throttle opening TVO are equal to or less than the maximum current value Imax,
Based on the current value I ₁ and the current value I ₂ at that time, the center differential current Ic is calculated using a predetermined arithmetic expression. Then P41
At, it is determined whether the center differential current Ic has the maximum current value Imax, and the center differential current Ic has the maximum current value Im.
When it is different from ax, that is, when it is smaller than the maximum current value Imax, "Ic = Ic" is set in P42. At this time, the center differential 20 is in an intermediate locked state, and in the case of "Ic = 0", it is in an unlocked state.
When the center differential current Ic is the maximum current value Imax, P4
The timer is set at 3 and the center differential current Ic is set at "Ic = Imax" at P44. At this time, the center differential 20 is completely locked. Then P4
In 5, the timer is counted up, and in P46, it is judged whether or not a predetermined time has elapsed. That is, when the center differential differential rotation speed ΔNc suddenly increases due to slip or the like, the center differential 20 is kept in a completely locked state for a predetermined time.

FIG. 9 is a flow chart showing a rear differential control current value setting routine in the automatic control in the "AUTO mode". The rear differential control current value setting routine is basically the same as the above center differential control current value setting routine. That is, as shown in FIG. 9, the rear differential current Ir is similarly set at P50. Next, in P51, it is determined whether or not the rear differential current Ir has the maximum current value Imax. If the rear differential current Ir is smaller than the maximum current value Imax, "Ir = Ir" is set in P52. At this time, the rear differential 22 is in the intermediate lock state,
Further, in the case of "Ic = 0", the unlocked state is set. When the rear differential current Ir has the maximum current value Imax, the timer is set at P53 and the rear differential current I is set at P54.
Set r as “Ir = Imax”. At this time, the rear differential 22 is completely locked. Next, in P54, the timer is counted up, and in P56, it is determined whether or not a predetermined time has elapsed. That is, when the rear differential differential rotation speed ΔNr rapidly increases due to slippage or the like, the rear differential 22 is held in the completely locked state for a predetermined time.

Next, the control contents when the brake switch and the ABS device are operated will be described with reference to Table 2.

[0023]

[Table 2]

The ABS device detects the skid state of each wheel based on the vehicle speed and each wheel speed, and controls the braking force of each wheel according to the skid state so as to cancel the locking tendency of the wheel during braking. is doing. However, in a vehicle having the front differential 21, the center differential 20, and the rear differential 22, it is impossible to estimate the vehicle speed when any of these is completely locked, so that it is difficult to perform appropriate ABS control. Becomes Therefore, in the embodiment of the present invention, when the brake switch 31 and the ABS device are activated, the control shown in Table 2 is performed.

First, in the "A mode", when the brake is actuated, that is, when the brake signal is ON, "I"
f = 0, Ic = 0, Ir = 0 ", and all the front differential 21, the center differential 20, and the rear differential 22 are unlocked. In the "C mode", if the brake signal is ON, "If = 0, Ic = 0.8 (within 0.2 seconds), Ir = 0" is set, and the front differential 21 and the rear differential 22 are unlocked. , The intermediate limiting state is set within 0.2 seconds after the center differential 20 is turned on to reduce the differential limiting force. Further, when the ABS device operates, that is, when the ABS signal is ON, “If =
0, Ic = 0 (within 0.2 seconds), Ir = 0 ”,
All of the front differential 21, the center differential 20, and the rear differential 22 are unlocked.

In the "R mode", the brake signal O
In the case of N, “If = 0, Ic = 0.8, Ir = 1.2”
Then, the front differential 21 is unlocked, the center differential 20 and the rear differential 22 are in an intermediate locked state, and the differential limiting force is reduced. If the ABS signal is ON,
"If = 0, Ic = 0, Ir = 0" is set, and all of the front differential 21, the center differential 20, and the rear differential 22 are unlocked.

In the "F mode", ABS control is not performed. Here, FIG. 10 shows the ABS in the “F mode”.
It is a flow chart which shows a control prohibition routine. Figure 10
Enter the mode at P60 as shown in
It is determined whether or not the mode input in is the "F mode". If the mode is other than the "F mode", ABS control is enabled in P62, and in the "F mode", the A mode is selected in P63.
BS control is prohibited.

In the control shown in Table 2 described above,
In the "A mode", "C mode", and "R mode", when the brake signal is ON, the control contents are unlocked or each diff that is in auto mode control is unlocked, and the control contents are The differential, which is in a completely locked state, is in an intermediate locked state. afterwards,
When the ABS signal is turned on, all of the front differential 21, the center differential 20, and the rear differential 22 are unlocked. Therefore, even if all the differentials are in the unlocked state when the ABS device is operating, the operation limiting force of each differential is lowered in advance when the brake is activated, so that the responsiveness of the ABS control can be improved. In the "F mode", the differential control is prioritized over the ABS control.
The driver can obtain the desired driving force.

Next, referring to Table 3, power saving control during high speed traveling will be described.

[0030]

[Table 3]

Table 3 is a flow chart showing power saving control during high speed running. First, "C mode", "R mode"
Further, in the "F mode", as shown in Table 2, the center differential 20 is forcibly set to the completely locked state. In each of these modes, the center differential 20 is set to the vehicle speed Vsp.
When the speed is 100 km / h or less, it is held in a completely locked state, and when it is 100 km / h or more, "auto mode control"
Switch to. Similarly, in the "R mode" and the "F mode", the rear differential 22 is forcibly put into a completely locked state. In the rear differential 22, the vehicle speed Vsp is 50k.
When it is less than m / h, it is kept in a completely locked state and 50 km
If / h or more, switch to "auto mode control".
In the "F mode", the front differential 21 is forcibly set to the completely locked state, and the vehicle speed Vsp is 30 km /
In case of h or less, it is held in a completely locked state and 30 km /
If h or more, the state is switched to the unlocked state.

The operation of the power saving control during high speed traveling will be described. In "C mode", "R mode" and "F mode", the vehicle speed Vsp is 100 km / h
In the above case, there is almost no possibility that each wheel will slip even during acceleration, and the vehicle will not travel off-road. Therefore, there is no problem even if the center differential 20 is switched from the completely locked state to the "auto mode control". Further, by switching to the "auto mode control", the unlocked state, the intermediate locked state, or the completely locked state is set under the predetermined condition as described above. Therefore, the electromagnetic multi-plate provided on the center differential 20 except when necessary. The clutch does not operate, which saves power and improves fuel efficiency. Further, in the case other than the completely locked state, when the vehicle turns, the center differential 20 operates and slip does not occur, so that the running resistance is reduced and fuel consumption is improved. Again 100
Since the center differential 20 is set to the "auto mode control" when traveling at a high speed of km / h or more, stability at a high speed can be obtained.

In the "R mode" and the "F mode", when the vehicle speed Vsp is 50 km / h or more, the rear differential 22 is similarly switched to the "auto mode control". Also in this case, similarly to the above, the fuel consumption can be improved by the power saving and the reduction of the running resistance, and the stability at high speed can be obtained. In "F mode", the front differential 21 is 30
The operability is improved by switching to the unlocked state in the case of km / h or more. Further, similarly, fuel efficiency can be improved by saving power.

In this power saving control during high speed running,
The vehicle speeds that are the standard for switching each diff from the forced complete lock state to the "auto mode control" or the unlock state are different. The reason for this is as follows. When the vehicle is traveling, it is necessary to reliably transmit the driving force from the engine to each wheel. Therefore, the center differential 20 close to the engine side is completely locked up to a relatively high speed of 100 km / h. In the rear differential 22 and the front differential 21, which affect only each wheel, the rear differential 22 is unlocked at a relatively low speed of 50 km / h or 30 km / h or more to save power. Improves fuel efficiency. Since the front diff 21 has a great influence on the operability, the front diff 21 is unlocked at a lower speed to improve the operability. Further, it is determined that the vehicle will not be driven off-road at a speed of 30 km / h or more, which requires the front differential 21 to be completely locked.

Next, the overall control contents of the vehicle control system according to the embodiment of the present invention will be described with reference to FIG. FIG. 11 is a flowchart showing the overall control contents of the vehicle control device according to the embodiment of the present invention. First, in P100, the center differential current value Ica and the rear differential current values Ira, A in the "auto mode control" are set.
BS signal, brake signal, mode signal, and vehicle speed Vsp
Enter. Next, in P102, it is determined whether or not it is the "A mode". In the case of the "A mode", it is determined in P104 whether or not the brake is on, based on the brake signal. If not, the process proceeds to P106. In P106, “If = 0, Ic = Ica, Ir = Ira” is set, the front differential is in the unlocked state, and the center differential and the rear differential are in “auto mode control”. When the brake is turned on in P104, "If =
0, Ic = 0, Ir = 0 ”, and all the differentials are unlocked.

If it is determined in P102 that the mode is not the "A mode", it is determined in P110 whether the mode is the "C mode". In the case of "C mode", it is determined in P112 whether or not the brake is on, and if not, the process proceeds to P114. Vehicle speed Vsp is 1 at P114
It is determined whether or not it is 100 km / h or more. If it is not 100 km / h or more, in P116, “If = 0, Ic = 2.
2, Ir = Ira ", the front differential is unlocked, the center differential is completely locked, and the rear differential is" auto mode control ". Vehicle speed Vsp is 100km /
If h or more, in P118, “If = 0, Ic
= Ica, Ir = Ira ", the front differential is in the unlocked state, and the center differential and the rear differential are in the" auto mode control ". When it is determined that the brake is on in P112, the ABS is detected in P120 based on the ABS signal.
Determine if the device is differential. When the ABS device is not differential, in P122, “If = 0, I
c = 0.8, Ir = 0 ”, the front differential and the rear differential are unlocked, and the center differential is intermediately locked. When it is determined in P120 that the ABS device is differential, in P124, “If = 0, Ic =
0, Ir = 0 ”, and all the differentials are unlocked.

When it is determined in P110 that the mode is not the "C mode", it is determined in P126 whether the mode is the "R mode". In the case of the "R mode", it is determined in P128 whether or not the brake is on, and if not, the process proceeds to P130. Vehicle speed Vsp is 1 at P130
It is determined whether or not it is 00 km / h or more, and if it is not 100 km / h or more, it is determined in P132 whether or not it is 50 km / h or more. If it is not 50 km / h or more, in P134, “If = 0, Ic = 2.2, Ir = 4.1” is set, and the front differential is in the unlocked state, and the center differential and the rear differential are in the completely locked state. If it is 50 km / h or more, in P136, “If = 0, Ic = 2.
2, Ir = Ira ", the front differential is unlocked, the center differential is completely locked, and the rear differential is" auto mode control ". If it is 100 km / h or more, in P138, “If = 0, Ic = Ica, I
"r = Ira" is set, the front differential is in the unlocked state, and the center differential and the rear differential are in the "auto mode control".

If it is determined at P128 that the brake is on, then at P140, A is determined based on the ABS signal.
It is determined whether the BS device is differential. If the ABS device is not differential, in P142, “If =
0, Ic = 0.8, Ir = 1.2 ", and the front differential is in the unlocked state, and the center differential and the rear differential are in the intermediate locked state. If it is determined in P140 that the ABS device is differential, in P144, “If =
0, Ic = 0, Ir = 0 ”, and all the differentials are unlocked.

When it is determined in P126 that the mode is not the "R mode", this case corresponds to the remaining "F mode", and the process proceeds to P146. Not more than 100 km / h at P146, not more than 50 km / h at P148, P150
When it is determined that each is not 30 km / h or more,
In P152, “If = 2.1, Ic = 2.2, I
r = 4.1 "is set, and all the differentials are completely locked. When it is determined at P150 that the speed is 30 km / h or more, at P154, “If = 0, Ic =
2.2, Ir = 4.1 "is set, and the front differential is unlocked and the center differential and the rear differential are completely locked. When it is determined in P148 that the speed is 50 km / h or more, in P156, “If = 0, Ic =
2.2, Ir = Ira "is set, the front differential is unlocked, the center differential is completely locked, and the rear differential is in" auto mode control ". 100 on P146
If it is determined to be equal to or higher than km / h, in P158, “If = 0, Ic = Ica, Ir = Ira” is set, the front differential is unlocked, and the center differential and the rear differential are set to “auto mode control”. .

[0040]

As described above, according to the present invention, the inter-axle differential is placed in an intermediate locked state when the brake is operated to reduce the differential limiting force of the differential limiting device, and further, when the anti-skid brake device is activated. Since the differential is unlocked, the functions of both the differential limiting device and the anti-skid braking device can be fully exerted, and the responsiveness of the anti-skid braking device can be further improved.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing an overall configuration of a vehicle control device of the present invention.

FIG. 2 is a cross-sectional view showing an electromagnetic multi-disc clutch provided on a center differential.

FIG. 3 is a flowchart showing a vehicle body speed calculation routine in "A mode" automatic mode control.

FIG. 4 is a flowchart showing a center differential differential rotation speed calculation routine in “A mode” auto mode control.

FIG. 5 is a flowchart showing a rear differential differential rotation speed calculation routine in the automatic mode control of “A mode”.

FIG. 6 is a flowchart showing a center differential current setting routine in the automatic mode control of “A mode”.

FIG. 7 is a diagram showing a relationship between a current value I ₁ and a center differential differential rotation speed ΔNc.

FIG. 8 is a diagram showing a relationship between a current value I ₂ and a throttle opening TVO.

FIG. 9 is a flowchart showing a rear differential control current value setting routine in the automatic mode control of “A mode”.

FIG. 10 is a flowchart showing an ABS control prohibition routine in “F mode”.

FIG. 11 is a flowchart showing the overall control contents of the vehicle control device according to the embodiment of the present invention.

[Explanation of symbols]

16 front wheel 18 rear wheel 20 center differential (center differential) 21 front differential (front differential) 22 rear differential (rear differential) 30 wheel speed sensor 31 brake switch 32 throttle sensor 41 anti-skid braking device control unit 43 differential control・ Unit 44 Manual switch 50 Electromagnetic multi-plate clutch

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Fumio Kageyama             3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda             Within the corporation (72) Inventor Yasuaki Wada             3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda             Within the corporation

Claims (3)

[Claims] 1. A differential limiting device for performing differential limiting with an inter-axle differential in a locked state, and an anti-skid braking device for detecting a skid state of each wheel and controlling a braking force of each wheel according to the skid state. In a control device for a vehicle having the following, the differential between the axle differentials is set to an intermediate lock state when the brake is activated to reduce the differential limiting force of the differential limiting device and the differential between the axles is unlocked when the anti-skid brake device is activated. A control device for a vehicle, comprising a motion limiting control means. 2. A differential limiting device for performing differential limiting with an inter-axle differential and an inter-wheel differential in a locked state, a skid state of each wheel is detected, and a braking force of each wheel is controlled according to the skid state. In a control device for a vehicle having an anti-skid brake device, first differential limiting means provided on an inter-axle differential,
A second differential limiting means provided on the wheel-to-wheel differential, and a first mode for automatically controlling the first differential limiting means and the second differential limiting means in accordance with operating states, respectively.
A mode setting means for setting the first differential limiting means in a completely locked state and a second mode for automatically controlling the second differential limiting means according to an operating state;
Switching means for switching between the mode and the second mode;
When the brake is activated in the mode, both the first differential limiting means and the second differential limiting means are unlocked, and the second differential limiting means is unlocked.
When the brake is operated in the mode, the first differential limiting means is set to the intermediate locked state, the second differential limiting means is unlocked, and when the antiskid brake device is activated, the first differential limiting means is operated. And a differential limiting control unit that brings the vehicle into an unlocked state. 3. The first differential limiting means and the second differential limiting means have electromagnetic clutches.
The control device for a vehicle according to item 1.