JP3428134B2 - Vehicle traveling state determination device and traveling state control device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheel of a moving vehicle .
The present invention relates to a vehicle traveling state determination device that determines a slip state or a vehicle abnormality, and a traveling state control device that controls a vehicle traveling state using the determination result.

[0002]

2. Description of the Related Art Conventionally, in order to safely and comfortably drive a vehicle, wheel slips and other abnormalities are detected,
Many devices are known for controlling the running state of a vehicle.
Usually, in such a device, in order to detect a slip or the like, the difference between the actually detected vehicle speed (or equivalent) and the target speed calculated from the vehicle control state or the like is obtained. The slip and other abnormalities are determined by. Then, based on this determination result, if slip is detected, control is performed so that the running state of the vehicle becomes stable by controlling the driving force and braking force of the vehicle to suppress slip. There is.

For example, in Japanese Patent Laid-Open No. 63-215430, the vehicle speed, the steering angle, and the rotational speed difference between the front and rear wheels are detected, and the amount of slip generation is calculated from these detected values. A device that suppresses slip by controlling the fastening force of the front and rear wheels according to the amount of generation is disclosed. In this device, the turning radius of the vehicle is calculated from the detected vehicle speed and the steering angle, and from the calculated turning radius and the vehicle speed, the difference in rotational speed between the front and rear wheels, which is estimated to occur due to turning traveling, is calculated. Is calculated, and the estimated rotation speed difference calculated is subtracted from the measured rotation speed difference between the front and rear wheels to obtain the slip generation amount.

[0004]

However, in this device, it is necessary to detect a lot of information such as the vehicle speed, the steering angle, and the rotational speed difference between the front and rear wheels in order to only control the fastening force of the front and rear wheels. Moreover, it is necessary to perform a complicated calculation such as calculating the rotational speed difference between the front and rear wheels estimated using these pieces of information.

As described above, in the method of calculating the target values such as the rotational speed difference between the front and rear wheels and comparing the measured values with the measured values to determine slips and other abnormalities, various control methods are used for calculating the target values. Since it is necessary to detect a large number of states and to perform complicated calculations based on the detected control states, there are problems that the device configuration becomes complicated and that processing takes time.

In order to solve the above problems, the present invention provides
An object of the present invention is to provide a vehicle running state determination device that has a simple configuration and can quickly determine a wheel slip state , and a vehicle running state control device that can control the vehicle running state using the determination result.

[0007]

The vehicle running condition determining device according to claim 1, which is an invention made to achieve the above object, has four wheels, as illustrated in FIG. 1 (a). Wheel speed detecting means for detecting each wheel speed of the vehicle, and two sets of addition values obtained by adding two diagonal wheels from each wheel speed detected by the wheel speed detecting means. The diagonal wheel speed difference calculating means for calculating the diagonal wheel speed difference, which is the difference between the diagonal wheel speed difference, and the value calculated by the diagonal wheel speed difference detecting means is outside the predetermined range, it is determined that the wheels are slipping. And a slip determining means.

According to a second aspect of the present invention, there is provided a vehicle running state determining device, wherein the vehicle running state determining device includes an alarm means for displaying a result of the slip determining means. Characterize. The wheel speed sensor abnormality determination device according to claim 3 includes a vehicle traveling state determination device according to claim 1 or 2 and the slip determination means .
More at wheels are determined to be slipping, the wheel speed ratio calculation means for calculating a wheel speed ratio between the slowest wheel and the other wheels, the calculated value of the wheel speed ratio calculation means outside the predetermined range In some cases, a wheel speed sensor abnormality determining means for determining that the wheel speed sensor detecting the lowest speed is abnormal is provided.

A vehicle running condition determining apparatus according to a fourth aspect of the present invention, as illustrated in FIG. 1B, wheel speed detecting means for detecting each wheel speed of a vehicle having four wheels, and the wheel speed. Diagonal wheel speed difference calculation for calculating the diagonal wheel speed difference, which is the difference between the two added values obtained by adding the two wheels that are diagonal wheels, from each wheel speed detected by the detection means Means, a change rate calculating means for calculating a change rate of the diagonal wheel speed difference calculated by the diagonal wheel speed difference calculating means, and a wheel when the calculated value of the change rate calculating means is outside a predetermined range. The vehicle running state determining apparatus according to claim 5, further comprising: a slip determining unit that determines that the vehicle is slipping. An acceleration state detecting means for detecting an acceleration state of the vehicle,
The first acceleration slip that determines that the wheels are in acceleration slip when the braking state detection means detects that the vehicle is accelerating and the slip determination means determines that the wheels are slipping. And a determining means.

A vehicle running state determining apparatus according to a sixth aspect of the present invention is a vehicle running state determining apparatus which has four wheels and is capable of driving front wheels and rear wheels simultaneously, as illustrated in FIG. 1 (c). Therefore, the acceleration state detecting means for detecting the acceleration state of the vehicle, the wheel speed detecting means for detecting each wheel speed, and the two wheels that are diagonal wheels from each wheel speed detected by the wheel speed detecting means. Diagonal wheel speed difference calculating means for calculating a diagonal wheel speed difference, which is a difference between two added values obtained by adding each other, and a diagonal wheel calculated by the diagonal wheel speed difference calculating means. The judgment value calculating means for calculating the change rate of the change rate of the speed difference and the acceleration state detecting means detect that the vehicle is accelerating, and the calculated value of the judgment value calculating means is outside the predetermined range. If the wheel is accelerating, a second acceleration And-up determining means, characterized by comprising a.

According to a seventh aspect of the present invention, there is provided a vehicle running state control device according to the fifth or sixth aspect of the present invention, and the vehicle running state determining device determines that the wheels are acceleratingly slipping. At the same time, an internal combustion engine output suppressing means for suppressing the output of the internal combustion engine is provided.

According to another aspect of the present invention, there is provided a driving state control device for a vehicle, wherein the driving force transmitting means transmits the driving force of the internal combustion engine to the front wheel drive shaft and the rear wheel drive shaft while allowing differential rotation, and the driving force. 5. A vehicle traveling state control device provided in a vehicle, comprising: a differential limiting unit that limits a rotational differential in a transmission unit; and a vehicle running state control device that controls a limiting force of the rotational differential according to a vehicle running state. 7. The traveling state determination device according to any one of 1 to 6 above, and when the traveling state determination device determines that the wheels are slipping or acceleratingly slipping, the limiting force of the rotational differential of the driving force transmission means increases. Thus, differential limiting force control means for controlling the differential limiting means is provided. The running condition judgment of the vehicle according to claim 9.
The stationary device detects each wheel speed of a vehicle having four wheels.
Wheel speed detecting means and the wheel speed detecting means
From each wheel speed, the two wheels that are diagonal wheels are added respectively.
The diagonal wheel speed difference, which is the difference between the two added values obtained by
Diagonal wheel speed difference calculating means for calculating and diagonal wheel speed difference detection
If the calculated value of the means is within the predetermined range, the wheel will
Grip determination means for determining that the
And are characterized.

[0013]

In the vehicle running condition determining apparatus according to claim 1 configured as described above, the diagonal wheel speed difference detecting means determines from the wheel speeds of the vehicle detected by the wheel speed detecting means,
The diagonal wheel speed difference, which is the difference between the two added values obtained by adding the two diagonal wheels, is calculated. If the calculated diagonal wheel speed difference is outside the predetermined range, the slip
The up determination means determines that the wheel is slipping .

That is, when all the wheels are traveling in grip, the speed of each wheel (right front wheel VFR, left front wheel VFL, right rear wheel V).
RR and left rear wheel VRF) are calculated by the following equations (1) to (4).

[0015]

[Equation 1] In addition, as shown in FIG. 2, K is the angular velocity of turning, RFL, R
FR, RRL, RRR is the distance from the turning center Po to each wheel,
W is the wheelbase of the vehicle, T is the tread of the vehicle, Bx
Represents the distance from the rear wheel to the turning axis, and By represents the distance from the axis connecting the front and rear wheels on the turning center P0 side to the turning center Po.

Therefore, when the diagonal wheel speed difference is calculated by substituting it into the following equation (5), the result becomes 0. Vx = (VFR ² + VRL ² ) − (VFL ² + VRR ² ) (5) However, when any of the wheels is slipping or drifting, the formulas (1) to (4) do not hold and the formula ( 5)
Has a certain value, the traveling state of the vehicle can be determined from the calculation result of the equation (5).

As described above, it is desirable to square each wheel speed and add the squared wheel speeds as the added value of the diagonal wheels in order to improve the determination accuracy of the running state. However, the wheel speeds may be added as they are without being squared. In this case, the determination accuracy is slightly lowered, but the arithmetic processing can be further simplified.

In the vehicle running condition determining device according to the second aspect, the alarm means displays the determination result of the slip determining means to notify the user whether or not the wheels are slipping . In the vehicle traveling state determination device according to claim 3, when the slip determination means determines that the wheels are slipping , the wheel speed ratio calculation means causes the wheel speed ratio between the lowest speed wheel and the other wheels. When the calculated value is out of the predetermined range, the wheel speed sensor abnormality determining means determines that the wheel speed sensor detecting the lowest speed is abnormal.

That is, when an abnormality occurs in the wheel speed sensor, such as a failure of the wheel speed sensor or a disconnection of a signal line for transmitting a signal detected by the wheel speed sensor, the wheel speed detected by the wheel speed sensor in which the abnormality has occurred is , 0 or extremely small. Therefore, if there is an abnormality in the wheel speed sensor, it is considered to be the wheel speed sensor that detects the lowest speed, and therefore the wheel speed ratio between this lowest speed wheel and other wheels must be determined. Thus, the abnormality of the wheel speed sensor can be determined.

According to another aspect of the present invention, there is provided a vehicle running condition determining device, wherein the diagonal wheel speed difference detecting means detects the respective wheel speeds of the vehicle from the wheel speeds detected by the wheel speed detecting means. The diagonal wheel speed difference, which is the difference between the two added values obtained by the addition, is calculated. Then, the change rate calculating means calculates the change rate of the diagonal wheel speed difference, and when the calculated value is outside the predetermined range, the slip determining means determines that the wheels are slipping.

That is, by calculating the change rate of the diagonal wheel speed difference, it is possible to know from the sign of the calculated value whether the diagonal wheel speed difference is increasing or decreasing. The increase in speed difference indicates that the wheels are not only slipping, but that the situation is getting worse. Therefore, the slip state of the wheel can be determined by the change rate of the diagonal wheel speed difference.

According to another aspect of the present invention, there is provided the vehicle running condition determining device, wherein the slip determining means determines that the wheels are slipping, and the acceleration detecting means detects that the vehicle is accelerating. The first acceleration slip determination means determines that the wheel is in acceleration slip.

That is, according to the apparatus of the fourth aspect, it is possible to determine the slip of the wheel regardless of the acceleration and the braking, but whether the slip is a slip during braking,
Since it cannot be determined whether the slip occurs on the drive wheels during acceleration, the present invention further determines the slip of the wheels by detecting the acceleration state of the vehicle.

According to another aspect of the present invention, there is provided a vehicle running condition determining device, wherein the diagonal wheel speed difference detecting means detects the respective wheel speeds of the vehicle from the two wheel speeds detected by the wheel speed detecting means. The diagonal wheel speed difference, which is the difference between the two added values obtained by the addition, is calculated. Then, the determination value calculation means calculates the rate of change of the rate of change of the diagonal wheel speed difference calculated by the diagonal wheel speed difference calculation means, and the calculated value is outside the predetermined range. When it is detected that the vehicle is accelerating, the second acceleration slip determination means determines that the wheels are in acceleration slip.

That is, in a vehicle in which the front wheels and the rear wheels can be driven at the same time, when any of the wheels runs idle due to wheel slippage or slip, a differential device provided to absorb the rotational differential of each wheel At the beginning of slip, a phenomenon in which the rotation of the slipping wheel suddenly changes appears, but this rapid change cannot be detected only by the rate of change of the diagonal wheel speed difference. By calculating the ratio and judging the calculated value, the state of the acceleration slip peculiar to the four-wheel drive vehicle is instantaneously judged.

As a method of detecting the acceleration state in the acceleration state detecting means according to the fifth and sixth aspects, besides the method of directly detecting the acceleration state of the vehicle from the vehicle speed or the like, braking of the vehicle is performed. An indirect method may be used in which the state is detected and an acceleration state is set if the braking is not being performed.

According to a seventh aspect of the present invention, there is provided a vehicle running state control device according to the fifth aspect of the present invention.
When it is determined that the wheel is accelerating and slipping, the internal combustion engine output suppressing means suppresses the output of the internal combustion engine and performs so-called traction control, thereby limiting the driving force transmitted to the wheel and causing an excess of the wheel. It prevents the transmission of various driving forces and suppresses wheel slip.

As a method of suppressing the output of the internal combustion engine, a control for reducing the amount of intake air flowing into the internal combustion engine by a throttle controllable regardless of the depression amount of the accelerator pedal,
There are retard control of the ignition timing of the spark plug, reduction control of the fuel injection amount, and the like, and any of them may be used.

Further, in the vehicle running state control device according to the eighth aspect, the vehicle running state determination device according to any one of the fourth to sixth aspects determines that the wheels are slipping or accelerating. Sometimes the differential limiting force control means
The differential limiting means is controlled so that the limiting force of the rotational differential of the driving force transmitting means is increased.

As a result, the driving force is transmitted to the wheels that are not slipping, and the rotation of the slipping wheels is suppressed.

[0031]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 is a schematic configuration diagram showing the configuration of a front engine / rear drive (FR) type vehicle equipped with the vehicle traveling state determination device of the first embodiment.

As shown in FIG. 3, the FR vehicle of this embodiment has an internal combustion engine 2 that generates power for driving the vehicle.
And left and right rear wheels R, which are drive wheels to which power from the internal combustion engine 2 is transmitted via the transmission 4 and the differential gear 6.
L, RR, left and right front wheels FL, FR that are driven wheels, and electromagnetic pickup-type wheel speed sensors 8FR, 8FL, 8RR, 8 that detect the rotational speeds of the wheels FL, FR, RL, RR, respectively.
RL, a warning lamp 10 provided on the front panel for displaying the running state of the vehicle, CPU, ROM, RA
It is configured as a well-known microcomputer including M and the like, calculates the diagonal wheel speed difference based on the detection signals from the above-mentioned sensors, determines the running state of the vehicle, and turns on the warning lamp 10 based on the determination result. An electronic control unit (ECU) 12 that executes alarm processing and the like is provided.

Next, the alarm process executed by the ECU 12 will be described with reference to the flowchart shown in FIG. In this process, the diagonal wheel speed difference is calculated, and it is determined whether or not the traveling state of the vehicle is stable based on the calculated value, and the determination result is displayed on the warning lamp 10 on the front panel to display the result. And is executed at a predetermined cycle (for example, 20 msec cycle).

As shown in FIG. 4, first, at step 110, the wheel speeds VFR, VFL, VRR, VRL are calculated based on the detection signals from the wheel speed sensors 8FR, 8FL, 8RR, 8RL, and then at step 120. Then, the diagonal wheel speed difference Vx is calculated using the following equation (6).

Vx = | (VFR ² + VRL ² ) − (VFL ² + VRR ² ) | (6) Further, if P0 in FIG. 2 is assumed to be on the perpendicular from the center of W, and approximated, Vx = | (VFR + VRL ) − (VFL + VRR) | (6) ′, which may be used as the diagonal wheel speed difference Vx. In this case, the calculation for obtaining the diagonal wheel speed difference Vx is simpler. Becomes

In the following step 130, step 120
The diagonal wheel speed difference Vx calculated in step 3 is filtered using the following equation (7). Vxf = {Vx (n) + Vx (n-1)} / 2 (7) Note that Vx (n) is the diagonal wheel speed difference calculated in this process, and Vx (n-1) is the previous difference. It is the diagonal wheel speed difference calculated in the processing. In other words, this filter processing is a kind of low-pass filter processing, and by using the average value with the previous measured value in the actual processing, it follows noise and instantaneous changes, and the processing is performed wastefully. It's something that doesn't happen. Hereinafter, the diagonal wheel speed difference is the value V filtered by the equation (7).
Refers to xf.

In the following step 140, the diagonal wheel speed difference V
It is determined whether xf is smaller than a predetermined value KV1 (eg, {5 km / h} ² ), and if it is smaller than the predetermined value KV1, the process proceeds to step 180, and the vehicle is in a stable running state and the front panel warning is given. The lamp 10 is turned off, and this processing ends.

On the other hand, if the diagonal wheel speed difference Vxf is larger than the predetermined value KV1, the routine proceeds to step 150, and the diagonal wheel speed difference Vxf is further set to the predetermined value KV2 (eg {10 km / h} ² ).
Determine if less than. And the diagonal wheel speed difference V
If xf is smaller than the predetermined value KV2, the routine proceeds to step 170, where it is determined that the vehicle is in an unstable running state, and the warning lamp 10 on the front panel is made to blink,
This process ends.

When it is determined in step 150 that the diagonal wheel speed difference Vxf is equal to or greater than the predetermined value KV2, the process proceeds to step 160, and the vehicle is considered to be in an extremely unstable running state. Warning lamp 10
Then, this process is terminated.

As described above, in the traveling state determination device of the first embodiment, the diagonal wheel speed difference Vxf is the predetermined value KV.
When it is 1 or less, it is determined that the vehicle is in a stable traveling state because all the wheels are gripped, and when it is greater than the predetermined value KV1 and less than or equal to the predetermined value KV2, the vehicle slightly slips on the wheels. It is determined that the vehicle is in an unstable traveling state, and when it is larger than the predetermined value KV2, it is determined that the vehicle is in an extremely unstable traveling state because a large slip has occurred in the wheels.

As described above, according to the running state determination device of this embodiment, the running state of the vehicle is determined from the diagonal wheel speed difference, and the diagonal wheel speed difference is obtained only from the wheel speed of each wheel. Since the calculation is performed, the sensors need only be a wheel speed sensor for each wheel, and the device configuration can be simplified. Further, since the calculation for calculating the diagonal wheel speed difference from each wheel speed is simple, the processing can be performed quickly.

Further, since the warning lamp 10 is turned off / blinking / lit according to the determination result, the driver can be made aware of the traveling state. Next, a second embodiment will be described. FIG. 5 is a schematic configuration diagram showing a configuration of a front engine / rear drive (FR) type vehicle equipped with the wheel speed sensor abnormality determination device of the second embodiment.

As shown in FIG. 5, the FR vehicle of this embodiment is different from the FR vehicle of the first embodiment in that the side brake switch (PKB) is turned on when the side brake is further operated and the braking force is working. 14 is provided, CPU, R
An electronic control unit (ECU) 16 configured as a well-known microcomputer including an OM, a RAM, etc. calculates a diagonal wheel speed difference and the like based on the detection signals from the above-mentioned sensors and switches to detect the wheel speed sensor. It is configured to execute a wheel speed sensor abnormality determination process for determining an abnormality.

Next, the wheel speed sensor abnormality determination processing executed by the ECU 16 will be described with reference to the flowchart shown in FIG. Note that this processing calculates the diagonal wheel speed difference, and when the ratio of the calculated value and the vehicle speed is out of the predetermined range, the abnormality of the wheel speed sensor detecting the vehicle speed of the currently lowest wheel is detected. It is determined whether or not there is, and is executed at a predetermined cycle (for example, 20 msec cycle).

As shown in FIG. 6, steps 210-23.
0 indicates steps 110 to 130 of the alarm processing shown in FIG.
And the filtered diagonal wheel speed difference V
Calculate xf. In the following step 240, the wheel speeds VFR, VFL, VRR, VRL calculated in the previous step 210 are calculated.
Among them, the one having the largest value is set as the vehicle body speed Vs, the one having the smallest value is set as the minimum wheel speed VL, and the one having the second smallest value is set as the medium and low wheel speed VM.

In step 250, the ratio Vxf / Vs of the diagonal wheel speed difference and the vehicle body speed is set to a predetermined value K1 (for example, 0.
7) It is determined whether or not it is larger than the predetermined value K1, and if the value is equal to or less than the predetermined value K1, the wheel speed sensors 8FR, 8FL, 8RR, 8RL are assumed to be operating normally, and the process proceeds to step 320.

On the other hand, the ratio of the diagonal wheel speed difference to the vehicle body speed Vxf /
If Vs is larger than the predetermined value K1, the routine proceeds to step 260, where it is judged whether the side brake switch (PKB) 14 is in the off state. Then, if the PKB 14 is not in the OFF state and the braking force by the side brake is working, it is determined that the abnormality in the diagonal wheel speed difference is due to the side brake, and the process proceeds to step 320.

When it is determined in step 260 that the PKB 14 is in the off state, the process proceeds to step 270, and it is determined whether the medium / low speed wheel VM is equal to or more than a predetermined value KV3 (for example, 10 km / h). This is the ratio of the diagonal wheel speed difference to the vehicle speed Vxf / V when the vehicle is turning at a low speed.
Since s may become larger than the predetermined value K1, this is a process for preventing erroneous determination. Further, the reason why the determination is made by using the medium / low wheel speed VM is that the wheel speed sensor of the wheel having the lowest wheel speed VL may have an abnormality such as a wire break, and thus the correct determination cannot be made. Because there is a nature.

If the medium / low wheel speed VM is smaller than the predetermined value KV3, it is determined that the vehicle is turning at a low speed and the step 3
If the medium / low wheel speed VM is greater than the predetermined value KV3, the process proceeds to step 280. Step 280
Then, the ratio VM / VL of the medium and low wheel speed and the minimum wheel speed is the predetermined value K2.
If it is larger than the predetermined value K2, that is, if the lowest wheel speed VL is extremely lower than the medium and low wheel speed VM, the wheel speed sensor that has detected the lowest wheel speed VL is disconnected. If it is highly possible that step 29
Move to 0. If the value is equal to or less than the predetermined value K2, the ratio VM / VL between the medium and low wheel speed and the minimum wheel speed is within the allowable range, and the process proceeds to step 320.

In step 290, the counter value CT is set to a predetermined value K3 (for example, 500: processing cycle 20 msec × 50).
0 = 10 seconds elapsed is measured), and if it is larger than a predetermined value K3, that is, step 250
If it is determined that there is a possibility of disconnection in 280 to 280 and the state continues for 10 seconds or more, step 30
If the counter value CT is equal to or less than the predetermined value K3, the wheel speed sensor that detects the speed of the wheel with the lowest wheel speed VL is disconnected, and the disconnection abnormality processing is executed. The process proceeds to 310, the counter value CT is incremented, and this processing ends.

Further, in steps 250 to 280, it is determined that the wheel speed sensor is not broken, and the process proceeds to step 320, where the counter value CT is cleared to 0 and this processing is terminated. The counter value CT is previously cleared to 0 in the initialization process performed immediately after the power is turned on.

In the disconnection abnormality process executed in step 300, various processes executed by the ECU 16 are switched to processes that do not use the wheel speed sensor determined to be disconnected. Alternatively, the display may be displayed on the display panel to notify the driver.

As described above, in the wheel speed sensor abnormality judging device of the second embodiment, the ratio Vxf / Vs of the diagonal wheel speed difference to the vehicle speed is larger than the predetermined value K1, and the braking force by the side brake 14 works. The middle / low wheel speed VM is equal to or higher than the predetermined value KV3, and the ratio VL / V of the lowest wheel speed to the middle / low wheel speed
It is determined that the wheel speed sensor is abnormal only when the state in which M is larger than the predetermined value K3 continues for the predetermined time or more.

Therefore, according to the wheel speed sensor abnormality judging device of the second embodiment, since the running state of the vehicle is judged by the ratio Vxf / Vs of the diagonal wheel speed difference and the vehicle speed, the diagonal wheel speed difference is simply calculated. It is possible to make a more accurate determination than when the traveling state of the vehicle is determined based on the size. That is, since the allowable range of variation of the diagonal wheel speed difference Vxf becomes large during high speed traveling, if the traveling state of the vehicle is judged by whether the diagonal wheel speed difference Vxf is larger than a predetermined value, high speed traveling is performed. At times, it is easy to determine that the traveling state is unstable. However, by making a determination based on the ratio Vxf / Vs of the diagonal wheel speed difference and the vehicle speed, it is possible to make an optimal determination according to the vehicle speed Vs. .

By determining the braking state by the side brake and the medium / low wheel speed VM, the same state as the abnormality of the wheel speed sensor occurs during the side brake braking or when the vehicle is turning at a low speed. There is no erroneous judgment. Further, since the abnormality of the wheel speed sensor is judged by the ratio VL / VM of the minimum wheel speed and the medium / low wheel speed, not only the abnormality of the state where the wheel speed sensor is completely disconnected, but also some signal due to poor contact or the like. It is also possible to detect an abnormality in the state where is detected.

Further, according to the present apparatus, when the abnormality of the wheel speed sensor is detected, various processes and controls using the measured value of the wheel speed sensor are performed without using the wheel speed sensor in which the abnormality is detected. Since they are switched, the influence of the abnormality of the wheel speed sensor can be minimized.

Next, the third embodiment will be described. Figure 7
FIG. 9 is a schematic configuration diagram showing a configuration of a front engine / rear drive (FR) type vehicle equipped with the traveling state control device of the third embodiment. As shown in FIG. 7, the FR vehicle of the present embodiment is different from the FR vehicle of the first embodiment in that the brake switch 18 that is turned on when the brake pedal is further operated and the braking force is working, and the internal combustion engine 2 is provided. A main throttle position sensor 24 that detects the opening of a main throttle valve 22 that opens and closes in the intake system in conjunction with the accelerator pedal 20, and a sub-throttle position sensor that detects the opening of a sub-throttle valve 26 provided for traction control. 28, a sub-throttle actuator 30 including a step motor and the like for opening and closing the sub-throttle valve 26.
An electronic control unit (ECU) 32, which is configured as a well-known microcomputer including M and the like, calculates the diagonal wheel speed difference based on the detection signals from the above-mentioned sensors and switches to determine the traveling state of the vehicle, The sub-throttle valve 26 is controlled based on the determination result to execute a sub-throttle control process for controlling the output of the internal combustion engine.

Next, the sub-throttle control process executed by the ECU 32 will be described with reference to the flowchart shown in FIG. It should be noted that this process is executed in a predetermined cycle (for example, 20 msec cycle). As shown in FIG. 8, steps 410 to 430 are exactly the same as steps 110 to 130 of the alarm processing shown in FIG. 4, and the filtered diagonal wheel speed difference Vxf is calculated.

In the following step 440, the change rate αxf of the diagonal wheel speed difference is calculated using the following equation (8). αxf = {Vxf (n) -Vxf (n-1)} / t (8) Note that t represents the cycle in which this process is executed.

Then, in step 450, it is determined whether or not the brake switch (STP) 18 is in the off state. If it is not in the off state, that is, the brake pedal is operated and the braking force is applied to the vehicle. If it is in the state, the process proceeds to step 530, and if it is in the off state, the process proceeds to step 460.

In step 460, it is determined whether the diagonal wheel speed difference Vxf is larger than a predetermined value KV4 (eg {10 km / h} ² ), and if it is larger than the predetermined value KV4, the vehicle is in an unstable running state. If there is, the process proceeds to step 470, and it is further determined whether or not the change rate αxf of the diagonal wheel speed difference is larger than zero.

When it is judged that the rate of change αxf of the diagonal wheel speed difference is larger than 0 and the diagonal wheel speed difference Vxf tends to increase, the routine proceeds to step 480, and the sub throttle actuator 30 is driven. Sub throttle valve 2
6 is moved in the closing direction by a predetermined amount. On the other hand, if it is determined that the change rate αxf of the diagonal wheel speed difference is 0 or less and the diagonal wheel speed difference Vxf tends to decrease, the process proceeds to step 490, and the sub-throttle valve 26 is moved to the current position. The sub-throttle actuator 30 is held so as to be held, and this processing is ended.

In the previous step 460, the diagonal wheel speed difference V
When xf is equal to or less than the predetermined value KV4 and it is determined that the vehicle is in a stable running state, the routine proceeds to step 500, where the main throttle opening degree is detected from the detection signals of the main throttle position sensor 24 and the sub throttle position sensor 28. Sm and sub throttle opening Ss are calculated,
In the following step 510, it is determined whether or not the sub throttle opening Ss is greater than or equal to the main throttle opening Sm.

When it is determined that the sub throttle opening Ss is smaller than the main throttle opening Sm, the process proceeds to step 520, and the sub throttle opening Ss approaches the main throttle opening Sm by a predetermined amount. The actuator 30 is driven in the opening direction, while it is determined that the sub throttle opening Ss is larger than the main throttle opening Sm, or in the previous step 450,
When it is determined that the brake switch 18 is not in the off state but the brake pedal is operated and the braking force is applied to the vehicle, the process proceeds to step 530, and the sub-throttle opening Ss becomes the main throttle opening Sm. The sub-throttle actuator 30 is driven in the closing direction so as to be the same, and this processing ends.

That is, when the diagonal wheel speed difference Vxf is large, the running state of the vehicle is unstable, and the unstable state is about to be promoted, the sub-throttle valve 26 is controlled and the throttle opening is changed. Since the driving torque transmitted from the internal combustion engine 2 to the wheels is suppressed by reducing the size, an excessive driving force is not applied to the wheels, and slips of the wheels are suppressed, so that the running stability of the vehicle and the running stability of the vehicle are reduced. The driving force of the vehicle is secured. When the diagonal wheel speed difference is small and the traveling state of the vehicle is stable, the sub throttle opening Ss is set to the main throttle so that the driving force according to the depression amount of the accelerator pedal 20 is applied to the wheels. It is controlled to be the same as the opening degree Sm.

As described above, according to the vehicle running state control device of the third embodiment, the vehicle is not being braked, the diagonal wheel speed difference Vxf is larger than the predetermined value KV4, and the diagonal wheel speed difference is larger. When Vxf tends to increase, it is determined that the wheels are accelerating and slipping, and the sub throttle opening Ss
By controlling the sub-throttle valve 26 so as to be smaller, the intake air intake amount is limited and the driving force of the internal combustion engine 2 is suppressed.

Therefore, the acceleration slip due to the excessive driving force applied to the wheels is suppressed, so that the vehicle can be driven stably and the driving force of the vehicle can be secured. Moreover, the determination as to whether or not to perform this control requires only the diagonal wheel speed difference calculated based on the output of the wheel speed sensor and the brake switch 18, so that the device configuration is simple and the determination is made. Since the processing is also simple, control can be performed with good responsiveness.

Next, a fourth embodiment will be described. Figure 9
FIG. 9 is a schematic configuration diagram showing a configuration of a four-wheel drive (4WD) type vehicle equipped with a vehicle traveling state control device of a fourth embodiment. As shown in FIG. 9, the four-wheel drive vehicle of this embodiment is
The internal combustion engine 2 that generates power for driving the vehicle and the power from the internal combustion engine 2 via the transmission 4 are transferred to the front wheel drive shaft 34.
And a center differential gear (hereinafter, simply referred to as a center differential) 38 that evenly distributes to the rear wheel drive shaft 36 and absorbs a rotation difference between the front wheel drive shaft 34 and the rear wheel drive shaft 36 that occurs when the vehicle turns. The differential limiting clutch 40 that limits the rotational differential of the steering wheel 38 and adjusts the torque distribution between the front and rear wheels, and the differential limiting clutch actuator 42 that drives the differential limiting clutch 40 that includes a hydraulic piston.
And power from the front wheel drive shaft 34 to the left and right front wheels FL, FR.
To the front differentials (hereinafter simply referred to as front differentials) 44 that absorb the rotational difference between the front wheels FL and FR and the power from the rear wheel drive shaft 36 evenly to the left and right rear wheels RL and RR. Distribute and each rear wheel R
A rear differential gear (hereinafter simply referred to as a rear differential) 46 that absorbs a rotation difference between L and RR, and wheels FR and F
It is configured as a well-known microcomputer equipped with wheel speed sensors 8FR, 8FL, 8RR, 8RL for detecting the wheel speeds of L, RR, RL, respectively, and CPU, ROM, RAM, and diagonally based on the detection signals from each sensor. An electronic control unit that executes a differential limiting force control process of calculating a wheel speed difference, determining a running state of the vehicle, and operating the differential limiting clutch 40 based on the determination result to control the differential limiting force ( ECU) 4
8 and.

Next, the differential limiting force control processing executed in the ECU 48 will be described with reference to the flowchart shown in FIG. It should be noted that this process is executed in a predetermined cycle (for example, 20 msec cycle). In this process, if the front wheels or the rear wheels slip and slip, the torque will not be transmitted to the non-idle wheels due to the differential of each differential gear, and the vehicle cannot be driven.
By limiting the rotational differential of the center differential 38 when the diagonal wheel speed difference is equal to or greater than a predetermined value, an appropriate driving force is transmitted to all the wheels. It should be noted that as the differential limiting force is reduced, the front wheels and the rear wheels rotate freely with each other, and as the differential limiting force is increased, mutual torques are transmitted, and the front wheels and the rear wheels rotate at rotational speeds close to each other. Come to do.

As shown in FIG. 10, steps 610-6
Reference numeral 30 denotes steps 110 to 13 of the alarm processing shown in FIG.
It is exactly the same as 0, and the filtered diagonal wheel speed difference Vxf is calculated. Further, step 640 is exactly the same as step 440 of the throttle control process shown in FIG. 8, and calculates the rate of change αxf of the diagonal wheel speed difference.

Then, in step 650, it is judged whether or not the diagonal wheel speed difference Vxf is larger than a predetermined value KV5 (for example, 5 km / h), and if it is the predetermined value KV5 or less, the vehicle is in a stable running state. If there is, the process proceeds to step 690, the differential limiting clutch actuator 42 is driven, and the differential limiting clutch 40 is operated by a predetermined amount in the direction in which the differential limiting force is reduced, and this processing is ended. On the other hand, if the diagonal wheel speed difference Vxf is larger than the predetermined value KV5, step 6
Then, the routine proceeds to 60, where it is determined whether or not the change rate αxf of the diagonal wheel speed difference is larger than zero. If the rate of change αxf is greater than 0, it is assumed that the diagonal wheel speed difference Vxf tends to increase, and the routine proceeds to step 670, where the differential limiting clutch actuator 42 is driven to increase the differential limiting force. If the rate of change αxf is 0 or less, the diagonal wheel speed difference Vxf tends to be maintained or decreased, and the step 68 is executed.
The processing shifts to 0, the current differential limiting force is retained, and this processing ends.

As described above, according to the vehicle running condition control apparatus of the fourth embodiment, when the diagonal wheel speed difference Vxf is larger than the predetermined value KV5 and tends to increase, that is, the wheels slip. When the state is deteriorating, the differential limiting force of the differential limiting clutch 40 is increased to strengthen the fastening force between the front and rear wheels.

Therefore, even if the wheels slip, the drive force of the internal combustion engine 2 is transmitted to the non-slip wheels by increasing the differential limiting force of the center differential 38.
The driving force of the vehicle can be secured. Moreover, the slipping wheels are the center differential 3 with the increased differential limiting force.
Since the rotation is suppressed by 8, the wheel can be quickly returned to a gripped state, that is, a stable traveling state.

Moreover, the determination as to whether or not to perform this control does not require the diagonal wheel speed difference calculated based on the output of the wheel speed sensor, so that the device configuration is simple and the determination process is also performed. Since it is simple, control can be performed with good responsiveness. Next, a fifth embodiment will be described.

FIG. 11 is a schematic configuration diagram showing the configuration of a four-wheel drive (4WD) type vehicle equipped with the acceleration slip determination device of the fifth embodiment. As shown in FIG. 11, the four-wheel drive vehicle of this embodiment uses the internal combustion engine 2 that generates power for driving the vehicle and the power from the internal combustion engine 2 via the transmission 4 to the left and right front wheels FL, FR and propeller shaft 50
Front differential gear 52 that absorbs the rotational difference between the front wheels FL and FR, and the power from the propeller shaft 50 is evenly distributed to the left and right rear wheels RL and RR, and between the rear wheels RL and RR. Of the rear differential gear 54 that absorbs the rotational difference between the internal combustion engine 2 and the rear wheels RL, R.
Driving force transmission clutch 5 for adjusting the driving force transmitted to R
6, wheel speed sensors 8FR, 8FL, 8RR, 8RL for detecting the wheel speeds of the wheels FR, FL, RR, RL, and CP, respectively.
It is configured as a well-known microcomputer equipped with U, ROM, and RAM, and calculates a diagonal wheel speed difference or the like based on the detection signal from each sensor to determine whether or not the wheel is in acceleration slip determination. An electronic control unit (ECU) 58 that executes processing is provided.

Next, the acceleration slip determination process executed by the ECU 58 will be described with reference to the flowchart shown in FIG. In this process, when an acceleration slip occurs in a four-wheel drive vehicle, the driving force is not transmitted to the gripping wheel due to the differential of each differential gear, while the rotational speed of the slipping wheel increases. By doing so, the acceleration slip is determined by detecting that the diagonal wheel speed difference changes abruptly at the initial stage of the slip, and is executed at a predetermined cycle (for example, 20 msec cycle).

As shown in FIG. 10, steps 710-7
Reference numeral 30 denotes steps 110 to 13 of the alarm processing shown in FIG.
It is exactly the same as 0, and the filtered diagonal wheel speed difference Vxf is calculated. In the following step 740, step 7
The maximum wheel speed is selected from the wheel speeds VFR, VFL, VRR, and VRL calculated in step 10, and this is set as the current vehicle body speed Vs.

Then, in step 750, the current vehicle body speed Vs (n) is calculated from the vehicle body speed Vs calculated in the previous processing.
It is determined whether or not it is larger than (n-1), that is, whether or not the vehicle is currently accelerating. If the vehicle is accelerating, the process proceeds to step 760. .

In step 760, the change amount Vα of the diagonal velocity difference Vxf is calculated using the following equation (9), and then step 7
At 70, the increase / decrease amount V of the change amount Vα is calculated using the following equation (10).
Calculate β. Vα (n) = Vxf (n) -Vxf (n-1) (9) Vβ = Vα (n) -Vα (n-1) (10) Note that Vxf (n) and Vα (n) are the current processing. Vxf (n-1) and Vα (n-1) are calculated values in the previous process. Then, here, the change amount is obtained, but since this processing is executed at every predetermined cycle, it is substantially equivalent to obtaining the change rate.

In the following step 780, it is determined whether or not the increase / decrease amount Vβ is larger than a predetermined value KV6 (eg, {5 km / h} ² ). If it is larger than the predetermined value KV6, it is determined that acceleration slip has occurred. If the increase / decrease amount Vβ is smaller than the predetermined value KV6, the process proceeds to step 790, and if the increase / decrease amount Vβ is smaller than the predetermined value KV6, this process is terminated as it is without acceleration slip.

In the acceleration slip processing executed in step 790, for example, the second or third fastest wheel speed is set as the vehicle body speed Vs,
It is conceivable to execute various processes by using the newly set vehicle body speed Vs. That is, it is considered that the wheel for which the fastest wheel speed is detected is slipping.

Further, as the acceleration slip processing, so-called traction control may be performed to display on the front panel that acceleration slip has occurred or to suppress the output of the internal combustion engine 2. Further, if the vehicle has an increasing engagement force of the driving force transmission clutch 56 or has the center differential gear and the differential limiting mechanism for limiting the rotational differential as shown in the fourth embodiment, the vehicle is provided with the differential limiting force. May be increased to control slip.

As described above, according to the vehicle acceleration slip determination apparatus of the fifth embodiment, when the vehicle is in an accelerating state, the increase / decrease value Vβ of the variation amount of the diagonal wheel speed difference is calculated, and this calculation is performed. Since it is determined whether or not the vehicle is accelerating slip based on the value, it is possible to correctly detect the state of accelerating slip, which is peculiar to a four-wheel drive vehicle, in which the diagonal wheel speed difference suddenly changes at the initial stage of the slip. it can.

Further, since such a state occurring at the initial stage of the slip is determined for determination, it is possible to control the acceleration slip with good responsiveness by using the determination result. Although some embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and can be implemented in various modes without departing from the scope of the present invention.

For example, in the above embodiment, the acceleration slip is determined and the control is performed so that the acceleration slip is suppressed. However, the slip in the braking state is determined so that the wheels are not locked. Alternatively, so-called anti-skid control for suppressing the braking force may be executed. In this case, the four wheels cannot be controlled individually, but it is sufficient to control the brake boost pressure for reducing the operating force at the time of braking to control all the wheels at the same time.

Further, in the first, third and fourth embodiments, by comparing the diagonal wheel speed difference Vxf with a predetermined value,
Although it is determined whether the control or the like is performed, the ratio Vxf / Vs of the diagonal wheel speed difference and the vehicle body speed may be compared with a predetermined value as in the second embodiment.

In addition, in the fourth embodiment, when it is judged that the slip occurs, the differential limiting force of the center differential 38 is controlled, but a clutch for adjusting the driving force is provided and the center differential is opened. In the case of the vehicle of the fifth embodiment which does not have the same, the effect similar to that of the fourth embodiment can be obtained by controlling the engagement force of the clutch instead of controlling the differential limiting force.

Further, the processing and control in each of the above embodiments may be used in combination.

[0089]

As described above, in the vehicle running condition determining apparatus according to the first aspect of the present invention, the diagonal wheel speed difference is calculated from each wheel speed, and when the calculated value is out of the predetermined range, , It is determined that the wheels are slipping . In this way, wheel slip is determined by the diagonal wheel speed difference,
Moreover, the diagonal wheel speed difference is calculated only from the wheel speed of each wheel.

Therefore, according to the vehicle running condition determining apparatus of the first aspect, if the speed of each wheel can be detected ,
Since the slip can be determined, the structure of the device can be simplified. Further, since the amount of calculation for calculating the diagonal wheel speed difference is small, the determination process can be performed quickly.

According to the vehicle running condition determination device of the second aspect, the user can recognize the slip of the wheel by the alarm means. In the vehicle running state determination device according to claim 3, when it is determined that the wheels are slipping, whether or not the wheel speed ratio between the lowest speed wheel and the other wheels is outside the predetermined range. By determining whether
The abnormality of the wheel speed sensor is judged.

Therefore, according to the vehicle running condition determining apparatus of the third aspect, it is possible to know whether or not the cause of the determination that the wheels are slipping is the abnormality of the wheel speed sensor. It is possible to take appropriate measures according to. For example, by switching the various controls that are executed when the vehicle is determined to be slipping to the controls that do not use the abnormal wheel speed sensor, the effect of the abnormal wheel speed sensor is minimized. be able to.

In the vehicle running condition determining apparatus according to the fourth aspect, the wheel slip is determined by determining whether or not the rate of change of the diagonal wheel speed difference is outside the predetermined range. Therefore, according to the vehicle running state determination device of the fourth aspect, it is possible to determine the slip of the wheels, which is the cause of the unstable running state of the vehicle, and to take appropriate measures according to the cause. You can

In the vehicle running condition determination device according to the fifth aspect, when the wheel is determined to be slipping, the acceleration condition of the vehicle is detected to determine whether the slip is an acceleration slip during acceleration. , It is determined whether or not there is a braking slip during braking.

Therefore, according to the vehicle running condition determination device of the fifth aspect, even the type of slip can be determined. Therefore, it is necessary to take more appropriate measures to restore the running condition of the vehicle to a stable condition. You can In the vehicle running state determination device according to claim 6, when the change rate of the change rate of the diagonal wheel speed difference is outside a predetermined range and the vehicle is accelerating, the wheels are accelerating and slipping. It has been determined.

Therefore, according to the traveling state determination device of the sixth aspect, the determination is made based on the change rate of the change rate of the diagonal wheel speed difference. It is possible to capture the phenomenon of the acceleration slip that is unique to the changing four-wheel drive vehicle, and it is possible to take an appropriate response to the acceleration slip. Moreover, since the phenomenon that occurs at the initial stage of such slip is captured and determined, it is possible to make a determination with good responsiveness.

In the vehicle running state control device according to the seventh aspect, when it is determined that the wheels are in acceleration slip, the output of the internal combustion engine is suppressed and the driving force transmitted to the wheels is appropriately limited. Traction control. Therefore, according to the vehicle running state control device of the seventh aspect, it is possible to return the vehicle to a stable running state by suppressing the acceleration slip that is the cause of the diagonal wheel speed difference. The driving force of the wheels can be secured.

Moreover, since the running condition of the vehicle is judged by using the running condition judging device according to the fifth or sixth aspect of the invention, the structure of the device can be simplified and the judging of the running condition can be performed quickly. Since this is performed, the output control of the internal combustion engine is also quickly performed, and the vehicle can quickly return to a stable running state.

According to another aspect of the vehicle running condition control device of the present invention, when it is determined that the wheels are slipping or accelerating, the differential rotation between the front wheel drive shaft and the rear wheel drive shaft is limited. There is. Therefore, according to the vehicle running state control device of the eighth aspect, the driving force is transmitted to the wheels that are not slipping, so that the driving force of the vehicle can be secured. Further, since the rotation of the slipping wheels is also suppressed, it is possible to return the vehicle to a stable traveling state in which the wheels do not slip.

In addition, since the running condition of the vehicle is judged by using the running condition judging device according to any one of claims 4 to 6, the structure of the device can be simplified and the judging of the running condition can be performed. Therefore, the differential limiting means is quickly controlled, and a stable traveling state can be quickly restored.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a configuration of the present invention.

FIG. 2 is an explanatory diagram illustrating calculation of a diagonal wheel speed difference.

FIG. 3 is a schematic configuration diagram of an FR vehicle according to the first embodiment.

FIG. 4 is a flowchart showing an alarm process.

FIG. 5 is a schematic configuration diagram of an FR vehicle according to a second embodiment.

FIG. 6 is a flowchart showing a wheel speed sensor abnormality determination process.

FIG. 7 is a schematic configuration diagram of an FR vehicle according to a third embodiment.

FIG. 8 is a flowchart showing a sub throttle control process.

FIG. 9 is a schematic configuration diagram of a 4WD vehicle of a fourth embodiment.

FIG. 10 is a flowchart showing a differential limiting force control process.

FIG. 11 is a schematic configuration diagram of a 4WD vehicle of a fifth embodiment.

FIG. 12 is a flowchart showing an acceleration slip determination process.

[Explanation of symbols]

2 ... Internal combustion engine 4 ... Transmission 6 ... Differential gear 8FR, 8FL, 8RR, 8RL ... Wheel speed sensor 10 ... Warning lamp 12, 16, 32, 48, 58 ... ECU 14 ...
Side brake switch 18 ... Brake switch 20 ... Accelerator pedal 22 ... Main throttle valve 24 ... Main throttle position sensor 26 ... Sub throttle valve 28 ... Sub throttle position sensor 30 ... Sub throttle actuator 34 ...
Front wheel drive shaft 36 ... Rear wheel drive shaft 38 ... Center differential gear 40 ... Differential limiting clutch 42 ... Differential limiting clutch actuators 44, 52 ... Front differential gears 46, 54 ... Rear differential gear 50 ...
Propeller shaft 56 ... Driving force transmission clutch

Continuation of the front page (56) References JP-A-6-286632 (JP, A) JP-A-5-294252 (JP, A) JP-A-3-54043 (JP, A) JP-A-5-1590 (JP , A) JP-A-3-182862 (JP, A) JP-A-63-305011 (JP, A) Fukuihei 4-79260 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB) Name) G01P 3/00-3/56 B60K 17/348 B60K 28/16 B60T 8/00

Claims (9)

(57) [Claims] 1. Wheel speed detecting means for detecting each wheel speed of a vehicle having four wheels, and wheel speeds detected by the wheel speed detecting means,
Diagonal wheel speed difference calculating means for calculating a diagonal wheel speed difference, which is a difference between two sets of added values obtained by adding two wheels that are diagonal wheels, and the diagonal wheel speed difference detecting means. A vehicle running state determination device comprising: slip determination means for determining that the wheel is slipping when the calculated value of is outside a predetermined range. 2. The vehicle traveling state determination device according to claim 1, further comprising an alarm unit that displays a determination result of the slip determination unit. 3. A running state determination device according to claim 1 or claim 2, wherein at the wheels by the slip determination means are determined to be slipping, the slowest wheel and the other wheel A wheel speed ratio calculating means for calculating a wheel speed ratio, and a wheel for determining that the wheel speed sensor detecting the lowest speed is abnormal when the calculated value of the wheel speed ratio calculating means is out of a predetermined range. A traveling state determination device for a vehicle, comprising: a speed sensor abnormality determination means. 4. A wheel speed detecting means for detecting each wheel speed of a vehicle having four wheels, and each wheel speed detected by the wheel speed detecting means,
Diagonal wheel speed difference calculating means for calculating a diagonal wheel speed difference, which is a difference between two added values obtained by adding two wheels that are diagonal wheels, and the diagonal wheel speed difference calculating means Change rate calculating means for calculating the change rate of the diagonal wheel speed difference calculated by, and when the calculated value of the change rate calculating means is outside the predetermined range,
A vehicle traveling state determination device comprising: a slip determination unit that determines that a wheel is slipping. 5. The vehicle traveling state determination device according to claim 4, wherein acceleration state detecting means for detecting an acceleration state of the vehicle, and that the acceleration state detecting means detects that the vehicle is accelerating, A traveling state of the vehicle, comprising: a first acceleration slip determination unit that determines that the wheel is in acceleration slip when the slip determination unit determines that the wheel is slipping. Judgment device. 6. A vehicle traveling state determination device having four wheels, capable of simultaneously driving the front wheels and the rear wheels, wherein an acceleration state detecting means for detecting an acceleration state of the vehicle and each wheel speed are detected. From the wheel speed detection means and each wheel speed detected by the wheel speed detection means,
Diagonal wheel speed difference calculating means for calculating a diagonal wheel speed difference, which is a difference between two added values obtained by adding two wheels that are diagonal wheels, and the diagonal wheel speed difference calculating means Determination value calculating means for calculating the change rate of the change rate of the diagonal wheel speed difference calculated by: and the acceleration state detecting means detects that the vehicle is accelerating, and the calculation of the determination value calculating means A vehicle running state determination device comprising: a second acceleration slip determination means for determining that the wheel is in acceleration slip when the value is out of a predetermined range. 7. The running state determination device according to claim 5 or 6, and an internal combustion engine output that suppresses the output of the internal combustion engine when the running state determination device determines that the wheels are acceleratingly slipping. A traveling state control device for a vehicle, comprising: a suppressing unit. 8. A drive force transmission means for transmitting a drive force of an internal combustion engine to a front wheel drive shaft and a rear wheel drive shaft while allowing rotational differential, and a differential limit for limiting rotational differential in the drive force transmission means. A driving state control device for a vehicle, which is provided in a vehicle including: and controls the rotation differential in accordance with a driving state of the vehicle, the traveling state according to any one of claims 4 to 6. A determination device and, when the traveling state determination device determines that the wheels are slipping or acceleratingly slipping, controlling the differential limiting means so that the limiting force of the rotational differential of the driving force transmitting means increases. A running condition control device for a vehicle, comprising: a differential limiting force control means; 9. Each wheel speed of a vehicle having four wheels is individually detected.
Wheel speed detection means to be output, From each wheel speed detected by the wheel speed detecting means,
Two pairs of additions obtained by adding two diagonal wheels
Diagonal wheel speed difference calculation that calculates the diagonal wheel speed difference, which is the difference between the calculated values
Means of delivery When the calculated value of the diagonal wheel speed difference detecting means is within a predetermined range,
If the wheels are gripping, the grip determination
Means and A traveling state determination device for a vehicle, comprising: