JPS6291326A - Unit for controlling driving force for vehicle - Google Patents

Abstract

PURPOSE:To secure traveling stability at the time of starting on a road surface of a low friction coefficient by operating a slip ratio between a tire and said road surface and its changing quantity per defined time and reducing driving force when said slip ratio or said changing quantity is larger than their respective set values. CONSTITUTION:A slip ratio between a tire and a road surface is operated (c) from the revolving speeds (a), (b) of driving and driven wheels and, further, the changing quantity of the slip ratio per defined time is operated (e). When the slip ratio is judged (d) larger than a first set value or the changing quantity is judged (f) larger than a second set value, a driving force is reduced (g). As a result, the traveling stability of a vehicle can be secured when conducting a quick acceleration at the time of starting on a road surface of a very low friction coefficient such as a frozen slope, etc., or when gently accelerating while traveling at a high speed, and the like.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a vehicle driving force control device.

[Conventional technology]

As a conventional vehicle driving force control device, for example, Japanese Patent Application Laid-open No. 6
There is one described in Japanese Patent No. 0-43133.

In an automobile engine output control device that controls engine output by changing the amount of fuel supplied to the engine according to the position of the accelerator pedal, it is used to detect drive wheel rotation speed, non-drive wheel rotation speed detection means, and rain detection means. A calculation means for calculating the slip ratio between the tires and the road surface from the output; a comparison means for comparing the calculated slip ratio with a set slip ratio; and a comparison means for comparing the calculated slip ratio with a set slip ratio; The system is characterized by being equipped with a slip rate control means that outputs a signal that forcibly reduces the fuel supply to the engine. By controlling the engine so that the slip ratio is below a certain value, starting performance and running stability on road surfaces with a low coefficient of friction are improved.

[Problem that the invention seeks to solve]

However, such conventional vehicle driving force control devices detect the rotational speed of the driving wheels and non-driving wheels, calculate the slip rate between the tires and the road surface from both rotational speeds, and calculate the slip rate. The vehicle's slip condition was determined by comparing it with a preset setting value and determining whether it was large or small, and the driving force was reduced only when the slip rate was greater than the set value. If you suddenly accelerate when starting on a road surface with an extremely low coefficient of friction,
If the amount of change in the rotational speed difference between the driving wheels and non-driving wheels is extremely large, even if the driving force is reduced after the slip ratio reaches the set value, the degree of reduction in the driving force will be small, making it difficult to control the slip, and the vehicle There was a problem that running stability was impaired.

[Means for solving problems]

The present invention has been made by focusing on these conventional problems, and as shown in the basic configuration diagram of FIG. A driving wheel rotation speed detection means, a non-drive wheel rotation speed detection means that detects the rotation speed of the non-driving wheels and outputs a detection signal, and a drive wheel rotation speed detection means and a non-drive wheel rotation speed detection means. a slip ratio calculation means for calculating the slip ratio between the tire and the road surface based on the detection signal; and a slip ratio calculation means for determining whether the slip ratio is larger than a first set value based on the calculation result of the slip ratio calculation means. a ratio determining means, a change amount calculation means for calculating the amount of change in the slip ratio per predetermined time, and a change amount calculation means for determining whether the change amount is larger than a second set value based on the calculation result of the change rate calculation means. A change amount determining means for determining whether the slip ratio is the first based on the determination result of the change amount determining means or the determination result of the slip rate determining means.
The above-mentioned problem can be solved by configuring a vehicle driving force control device including a driving force control means that reduces the driving force when the amount of change is larger than a set value or when the amount of change is larger than a second set value. It is characterized by solving points.

[Effect]

In this invention, the driving wheel rotational speed detection means detects the rotational speed of the driving wheels, and the non-driving wheel rotational speed detection means detects the rotational speed of the non-driving wheels. The slip ratio calculation means calculates the slip ratio between the tire and the road surface based on the rotational speed of the tire, the change amount calculation means calculates the amount of change in the slip ratio per predetermined time, and the slip ratio determination means calculates the amount of change in the slip ratio per predetermined time using the change amount calculation means. Determining whether the slip rate is greater than the first setting value, and determining whether the amount of change is greater than the second setting value by the change amount determining means, and determining whether the slip rate is greater than the first setting value. When the amount of change is greater than the value or the amount of change is the second
When the driving force is greater than the set value, the driving force control means reduces the driving force by controlling, for example, the closing speed of the throttle valve, thereby reducing the driving force in accordance with the slip ratio or the amount of change in the slip ratio. To ensure running stability of a vehicle even in a running pattern.

〔Example〕

The present invention will be explained below based on illustrated embodiments.

2 to 6 show an embodiment of the present invention, which is applied to a rear wheel drive vehicle.

First, to explain the configuration, reference numeral 1 shown in FIG. 2 is an accelerator potentiometer, which is configured to be linked to the depression of the accelerator pedal 2, and the accelerator which has a voltage corresponding to the amount of depression of the accelerator pedal 2. The signal DA is output to the control device 3.

The control device 3 includes a microcomputer 4, an A/D converter 5, an F/V converter 6, and a motor drive circuit 7, and includes an A/D converter connected to the F/V converter 6. converter 5
and a motor drive circuit 7 are connected to the microcomputer 4. The microcomputer 4 has an interface circuit 4a.

It has an arithmetic processing unit (CPU) 4b and a storage device 4c such as RAM or ROM, and the voltage output from the accelerator potentiometer 1 and the F/V converter 6 is transmitted through the A/D converter 5 and the interface circuit 4a. The data is supplied to the arithmetic processing unit 4b, and the arithmetic processing unit 4b is operated according to the program 1,a stored in advance in the storage device 4C.

The graphs shown in FIGS. 5 and 6 are stored in the storage device 4C.
Each is stored in its corresponding storage area in the form of a storage table. Note 1 corresponding to the graph shown in Figure 5
Table a is the stroke amount-target opening conversion table 4.
d, which converts the stroke amount I of the accelerator pedal 2 shown on the horizontal axis into the target opening degree θ0 of the throttle valve shown on the vertical axis, and the rate of increase in the target opening degree θ0 is higher than the rate of increase in the stroke amount. is set to be large (so that it curves upward). Moreover, the memory table corresponding to the graph shown in FIG. 6 is the deviation to morph speed conversion table 4e.
, which converts the deviation Dir of the throttle valve opening (not shown on the horizontal axis) into motor speed (not shown on the vertical axis), and the motor speed is set to increase in proportion to the increase in deviation Dir. .

Furthermore, the storage device 4C includes a reference slip rate recording area 4f in which a preset reference slip rate So is stored;
Similarly, a reference change amount record area 1a 4g stores a preset reference change amount ΔSo, a target opening storage area 4h stores a target opening degree θ0 of the throttle valve 17, and normal rotation of the step motor 16.

A motor state specification storage area 41 in which a specified value specifying reverse rotation or holding is stored, a starting cycle storage area 4j in which the starting cycle of the OCT interrupt is stored, and a flag specifying the rotation direction of the step motor 16 is stored. It has a morph rotation direction storage area 4 and an up/down counter 4m in which a value corresponding to the actual opening of the throttle valve 17 is stored.
The 001 interrupt is executed based on the cycle time stored in the activation cycle storage area 4.

The up/down counter 4m is capable of counting and amplifying the number of steps required for the step motor 16 to drive the throttle valve 17 from the fully closed state to the fully open state. It is set to 0 in the fully closed state.

The F/V converter 6 also includes a rear wheel rotation speed detector 10 which is a driving wheel rotation speed detection means for detecting the rotation speed of the rear right wheel 8 and the rear left wheel 9 which are driving wheels. Rotation speed signal D
Vr and a right front wheel rotation speed detector 13 and a front left wheel rotation speed detector 14 which are non-driving wheel rotation speed detection means that individually detect the rotation speeds of the front right wheel 11 and the left front wheel 12, which are non-driving wheels.
Right front wheel and left front wheel rotation speed signals from D Vfr, D
Vfl are respectively supplied. Rear wheel rotation speed detector 10
The rotation speed of the driving wheels is detected by detecting the rotation speed of the differential gear 15 that transmits the driving force to the rear left and right wheels 8.9, and the rear wheel rotation is generated by a pulse signal with a frequency corresponding to the rotation speed. Outputs a number signal DVr. Further, the right front wheel rotation speed detector 13 and the left front wheel rotation speed detector 14 directly detect the rotation speed of the front left and right wheels 11 and 12, and generate pulse signals of the right front wheel and the left front wheel with a frequency corresponding to the rotation speed. Outputs rotation speed signals DVfr and DVfl, respectively.

These front wheel and rear wheel rotation speed signals DVr, DVfr
and DVfl are supplied to the F/V converter 6, which converts these input signals into voltages corresponding to their respective frequencies, and sends out the rotational speed signals DV to the A/D converter 5. The A/D converter 5 to which the rotational speed signal DV and the accelerator signal DA are supplied converts them into digital signals and outputs them to the microcomputer 4.

As a result, the microcomputer 4 receives the input rotation speed signals DV from the three rotation speed detectors 10, 13, and 14.
and accelerator signal D from accelerator potentiometer 1
A control process, which will be described later, is executed based on A, and the step rate S
Alternatively, the control signal CS is outputted to the motor drive rgJ path 7 in accordance with the amount of change ΔS. Accordingly, the motor drive circuit 7 outputs a drive current to the step motor 16 based on the control signal supplied from the microcomputer 4, and causes the step motor 16 to rotate forward or reverse, or maintains a non-rotating state.

The rotation shaft 16a of the step motor 16 is constructed integrally with the rotation shaft of the throttle valve 17. For example, when the step motor 16 rotates in the normal direction, the throttle valve 17 is opened, and when the step motor 16 rotates in the reverse direction, the throttle valve 17 is closed.

The arithmetic processing unit 4b of the microcomputer 4 is R
For example, 1 shown in FIG.
Arithmetic processing is performed according to a timer interrupt processing program that is executed every 00m5ec, and based on the processing results, an overflow counter interwoven interrupt processing (001 interrupt) shown in FIG. 4, for example, is executed every startup cycle.

That is, in step (2), the rear wheel rotation speed signal DVr of the rear wheel rotation speed detector 10 is read, the rotation speed of the rear wheel 8.9 which is the drive wheel is calculated based on it, and this is stored as the drive wheel rotation speed Vr. It is temporarily stored in a predetermined storage area of the device 4C.

Next, proceed to step ■, and detect the right front wheel rotation speed detector 13.
The right front wheel rotational speed signal DVfr is read, the rotational speed of the right front wheel 11, which is a non-driving wheel, is calculated based on the rotational speed signal DVfr, and this is temporarily stored in a predetermined storage area of the storage device 4C as the right non-driving wheel rotational speed Vfr.

Next, move to step ■ and check left front wheel rotation speed detector 1.
4 reads the left front wheel rotation speed signal DVf+, calculates the rotation speed of the left front wheel 12 which is a non-driving wheel based on it, and temporarily stores this as the left non-driving wheel rotation speed Vfl in a predetermined storage area of the storage device 4C. .

Next, the process moves to step (2), and the right non-driving wheel rotational speed Vfr in step (2) and the left non-driving wheel rotational speed Vf in step (2) are determined.
Read out the left and right non-driving wheel rotation speed Vfr,
The rotational speed of the entire non-driving wheels is calculated based on Vfl, and this is written as the non-driving wheel rotational speed Vf.1. It is temporarily stored in a predetermined storage area of the α device 4c. This non-driving wheel rotation speed Vf is
In this embodiment, the average value of the rotation speeds of the front left and right wheels 11.12 is used.

Next, the process moves to step (2), where the drive wheel rotation speed Vr in step (2) and the non-drive wheel rotation speed (Vf) in step (2) are read out. , 9 is calculated as the slip rate S between the tires and the road surface for the entire vehicle.

Next, the process moves to step ■, reads out the slip rate S new calculated this time and the slip rate 5 old calculated at the previous timer interrupt, and calculates the current slip rate S n
The amount of change ΔS in the slip rate S is calculated by subtracting the previous slip rate 5old from eiy.

Next, the process proceeds to step (3), where the first setting value S stored in advance in the reference slip ratio storage area 4g of the storage device 4C is
o (for example, 0.2) and the slip rate S calculated in step ■, and the slip rate S is the first setting value S.
It is determined whether the value is greater than o. As a result of the determination, if the slip ratio S is larger than the first set value So, control is performed to reduce the driving force in step (2), while if the slip ratio S is smaller than the first set value So, the process moves to step (2).

In this step (2), the second set value ΔSo stored in advance in the reference change amount storage area 4g of the storage device 4c and the slip ratio change amount ΔS calculated in step (2) are read out, and the slip ratio change amount ΔS is It is determined whether or not the set value ΔSo is greater than the set value ΔSo.

As a result of the determination, if the amount of change in slip ratio ΔS is larger than the second set value ΔSo, control is performed to reduce the driving force in step (2), while if the amount of change in slip ratio ΔS is smaller than the second set value ΔSo, step (2) is performed. and normal driving force control of the step [phase].

The above-mentioned driving force reduction control is performed in step
This is done by entering a command value 0, which specifies the target opening θ0 of the throttle valve 17 to be fully open, in the target opening ta area 4h of 4c.

Next, the process moves to step [phase], and the current opening degree θ, which is the content of the up/down counter 4m (0 when fully opened) in the storage device 4c, and step ■ are specified, or step [phase], which will be described later, is specified.
read out the target opening θ0 searched for in [phase], subtract the current opening θ from the target opening θ0 to calculate the deviation Dir of the current opening θ with respect to the target opening θ0, and store this in a predetermined value in the storage device. Temporarily stored in the storage area.

In the next step (2), the deviation Dir calculated in step [phase] is read out, and the motor speed is searched from the deviation Dir with reference to the deviation-motor speed conversion table 4e stored in the memory bag W4c.

Next, the process moves to step @, reads the step [phase] deviation Dir, and based on this, it is determined whether to rotate the step motor 16 forward or reverse, or whether to maintain the current state, and a predetermined value representing the determination result is determined. 1. Save the value to the motor status specification in the storage device 4C. It is temporarily stored in the a area 4j. The decision in this case is made by looking at the content of the deviation Dif, and when the deviation Dir is positive, the rotation is forward, when the deviation Dir is negative, the rotation is reversed, and when the deviation Dir is 0, the current rotation is maintained. It is determined that

Next, the process moves to step [phase], and based on the motor speed calculated in step 0, the activation cycle of the ○C1 interrupt, which will be described later, is determined, and the determined time is stored in the activation cycle storage area 4j of the storage device 4C.

This starting cycle is determined based on the motor speed determined based on the deviation Dif, regardless of the magnitude of the slip ratio S with respect to the first set value SO and the magnitude of the slip ratio variation ΔS with respect to the second set value ΔSo. The time is set.

In the next step ■, the deviation Di of step [phase] is
Based on r, a flag designating the rotation direction of the step motor 16 is set in the motor rotation direction storage area 4k of the device 1a 4C.

This ends the timer interrupt processing and returns to the main program, and then shifts to the OCI interrupt processing shown in FIG.

In addition, in the driving force normal control, first, in step ■,
The accelerator signal DA from the accelerator potentiometer 1 is read, the amount of depression of the accelerator pedal 2 is calculated based on it, and this is temporarily stored in a predetermined register jQ GW area of the storage device as a pedal stroke measure.

Next, the process moves to step [phase], reads out the stroke measurements of step and /p, refers to the stroke amount-target opening conversion table 4d stored in the storage device/IC, and calculates the stroke amount of step [phase]. This is performed by searching the target opening degree θ0 of the throttle valve 17 from ilL. Then, proceeding to the step [phase], the step [phase] described above is performed.
- Execute the processing in step (2).

Next, the OCR interrupt processing shown in FIG. 4 will be explained. As described above, this OCI interrupt processing is executed according to the activation cycle of the time set in step 0.

That is, first, in step [phase], the step motor 16
It is determined whether or not to maintain the current rotational position and set it to non-rotation. The determination in this case is executed by looking at the contents of the motor state designation storage area 41 for step [phase]. As a result of the determination, if it is determined that the current rotational position of the step motor 16 is to be maintained, the current ○CI interrupt processing is finished, and this OCI is restarted according to the startup cycle of the OC■ interrupt processing. Either execute the interrupt process, or return to the main program and execute the timer interrupt process shown in FIG. 3 after a predetermined time.

On the other hand, if it is determined in step [phase] that the current rotational position of the step motor 16 is not to be maintained, the process moves to step (2) and it is determined whether or not to rotate the step motor 16 in the normal direction. In this case, the determination is also made in step [
phase], the motor state specification storage area 4 of step 0
This is done by looking at the contents of 1. As a result of the determination, the step motor 16 is rotated in the normal direction (direction to open the throttle valve 17).
To do so, move to step @, add 1 to the current value θ of the up/down counter 4m, and then proceed to step ■
On the other hand, when the step motor 16 is reversed (in the direction of closing the throttle valve I7), the step goes to step [phase], 1 is subtracted from the current value θ of the up-down counter 4m, and then the step goes to step ■. .

In this step @, the drive signal C81 is used to rotate the step motor 16 forward by one step, or the drive signal C81 is to rotate the step motor 16 in the reverse direction by one step.
8 is output, and this ends the current OCI interrupt processing.

The processing of steps ① to ③ constitutes a slip ratio calculation means, the processing of step ③ constitutes a change amount calculation means, the processing of step ③ constitutes a slip ratio determination means,
The process of step ■ constitutes a change amount determination means, and further,
The processing of steps ① to ② and steps [phase] to step ③ and the step motor 16 constitute a driving force control means.

Next, the effect will be explained.

Now, assuming that the vehicle is in a stopped state, when the timer interrupt process shown in FIG. 3 is executed at predetermined intervals in this state, first, in step Calculate the wheel rotation speed Vr, read the right front wheel rotation speed signal DVfr in step 2, calculate the right non-driving wheel rotation speed Vfr based on this, and read the left front wheel rotation speed signal DVfl in step Based on this, the left non-driving wheel rotation speed Vfl is calculated.

Next, the process moves to step (2), and the right non-driving wheel rotational speed Vfr in step (2) and the left non-driving wheel rotational speed Vf in step (2) are determined.
1 is read out, and based on these, the non-driving wheel rotation speed Vf is calculated, and in the next step (■), the driving wheel rotation speed Vr of step (■) and the non-driving wheel rotation speed Vf of step (2) are read out.
Based on these, the slip rate S between the tire and the road surface at the drive wheel 8.9 is calculated. Then, proceed to step ■, and calculate the current slip rate S n calculated in step ■.
ew and the previous slip rate 5 old are read, and the previous slip rate S old is subtracted from the current slip rate 5ne- to calculate the amount of change ΔS in the slip rate S.

Then, in step ■, the first setting value So stored in the reference step rate storage area 4f of the memory word W4C and the slip rate S calculated in step ■ are read out, and they are compared to determine the magnitude, and , in step ■, the memory word M
The second set value ΔSo stored in the reference variation storage area 4f of 4C and the slip ratio variation Δ calculated in step ■
S is read out and compared to determine the size.

At this time, assuming that the vehicle is stopped on a road surface with an extremely low coefficient of friction, such as on an icy road, by performing a sudden start operation from this state, the front and rear wheels 8, 9, 1
1. If a sudden difference in rotational speed occurs between the two, the drive wheels 8 and 9
Even before the slip ratio S calculated based on the actual rotational speed of the non-driving wheels 11 and 12 reaches the first set value So, it is determined in step (2) that ΔS>ΔSO.

Therefore, the process moves to step (2), where driving force reduction control is performed to specify the target opening θ0 as fully closed, and in the next step [phase], the target opening θ0 of step (2) and the current opening of the up/down counter 4m are determined. The degree θ is read out and the deviation Dir is calculated.

In this case, assuming that the current opening θ of the throttle valve 17 is wide open due to the starting operation and the engine is generating a large driving force, the target opening θ0 is O, so the step [phase] deviation Dir is a large negative value.

Therefore, in the next step 0, a relatively high motor speed corresponding to the deviation Dir of step [phase] is searched,
In the next step @, it is determined that the motor should be reversed, and in the next step 0, a short activation period corresponding to the motor speed is set, and furthermore, in step 2, a flag regarding reversal is set.

As a result, following this timer interrupt processing, the OCI of FIG.
When the interrupt process is executed, first, it is determined at step [phase] that the motor is not held, and then, at step 0, it is determined that the motor is to be reversed, so the current value of the up/down counter 4m is set at step [phase]. 1 is subtracted from θ, and the process moves to step (2), where a control signal C8 for rotating the step motor 16 in the reverse direction by one step is output to the motor drive circuit 7, and this motor drive circuit 7 receives the motor drive signal. Output to step motor 16. As a result, the step motor 16 rotates one step, and the throttle valve 17 is closed by the rotation angle.

Subsequently, when the next OCI interrupt is started due to the short startup cycle set in step @, 1 is subtracted from the current value θ of the up/down counter 4m in step [phase] through step [phase] and step ■. However, in the next step [phase], a motor drive signal for further rotating the step motor 16 by one step in the reverse direction is output to the step motor 16 via the motor drive circuit 7. As a result, the step motor 16 rotates one step,
The throttle valve 17 is further closed by the rotation angle.

This 001 interrupt continues until the predetermined time required for one cycle of the timer interrupt process shown in FIG. 3 has elapsed.

Therefore, when starting on a road surface with a low coefficient of friction as described above, if a large driving force is suddenly applied by briefly connecting a clutch device (not shown), the rotational speed between the driving wheels and the non-driving wheels will decrease. The slip rate S calculated based on the difference is the first
If there is a sudden difference in rotation speed between the front and rear wheels even before the set value So is reached, the amount of change ΔS in the slip ratio S calculated from the change in the rotation speed difference Based on this, control is executed to quickly close the throttle valve 17 and quickly reduce the driving force. Therefore, slip of the vehicle can be suppressed at an early stage, thereby ensuring running stability at the time of starting on a road surface with a low friction coefficient.

Thereafter, the vehicle shifts to a running state, and the drive wheels 8.9 are assumed to be in a slip state of a predetermined level or higher (S=0.2 or higher) during slow acceleration, for example, during high-speed running, and then the slip rate in step (3) is Needless to say, it is determined that S>So in step (2), even though it is not necessary to determine whether to reduce the driving force by looking at the amount of change ΔS in S, and as a result, the process moves to the driving force reduction control in step (2). Therefore, in the same way as described above, the step motor 1
A control signal for rotating the motor 6 by one step in the reverse direction is output to the motor drive circuit 7, which outputs a motor drive signal to the step motor 16, and the step motor 16 rotates one step in the reverse direction. . As a result, the throttle valve 17 is closed by the rotation angle corresponding to one step of the step motor 16, and the above process is repeated until the determination of the slip ratio S becomes S≦So, and in this way, the driving force is reduced. Ru.

Therefore, for slips that occur during slow acceleration such as when driving at high speeds, vehicle slip is determined by looking at the magnitude of the slip ratio S itself, without looking at the amount of change ΔS in the slip ratio S, and the slip Since driving force reduction control is executed depending on the state, running stability can be ensured during high-speed running.

If the slip rate S is less than the set value SO, the process goes through steps ■ and step ■ to the driving force normal control in step ■.First, in step ■, the stroke measurement of the accelerator pedal 2 is read, and the next control is performed. In step [phase], the target opening degree θ0 corresponding to the stroke amount is searched by referring to the stroke amount-target opening degree conversion table 4d. Therefore, in this Kl iJJ force normal control, the step motor 16 is rotationally driven in the forward or reverse direction or rotated at the current position by the motor speed according to the deviation Dir based on the target opening degree θ0 corresponding to the stroke measurement of the accelerator pedal 2. is maintained.

Therefore, in the first embodiment, when the slip rate S of the vehicle (drive wheel) is equal to or greater than the reference slip rate So, or the amount of change ΔS in the slip rate S is the reference amount ΔS.

In any of the above cases, it is determined that the vehicle is in a slip state exceeding the standard, and the throttle valve 17 is closed to reduce the driving force. It is possible to effectively suppress vehicle slippage and vehicle slippage during slow acceleration such as during high-speed driving, and it is possible to ensure running stability of the vehicle in any running pattern.

In the above embodiment, the driving force is reduced by closing the throttle valve 17, but the present invention is not limited to this. For example, the fuel supply may be cut or reduced, or the driving force may be braked. Of course, it is also possible to use a combination of these, or a combination of these and the throttle valve control described above.

Further, the control device 3 is not limited to the above-mentioned configuration, and can be configured with electronic circuits such as a subtraction circuit, a comparison circuit, and a logic circuit.

Further, in the above embodiment, the step motor 16 is used as the driving force control means, but the driving force control means is not limited to this. be able to. Furthermore, in the above embodiments, an example of a rear wheel drive vehicle has been described, but it goes without saying that the present invention can be applied to a front wheel drive vehicle.

〔Effect of the invention〕

As described above, according to the present invention, the drive wheel rotation speed detection means, the non-drive wheel rotation speed detection means, and the slip ratio between the tire and the road surface are calculated based on the rotation speeds of the drive wheels and the non-drive wheels. a slip ratio calculation means for calculating the amount of change in the slip ratio per predetermined time; a slip ratio determination means for determining whether the slip ratio is larger than a first set value; a change amount determination means for determining whether or not the amount of change in the slip ratio is greater than a second set value; Since the vehicle driving force control device is equipped with a driving force control means that reduces the driving force when the driving force is greater than a set value of The slip rate can be determined using two methods: the slip rate calculated from the number and the amount of change thereof. Therefore, even if the vehicle suddenly accelerates when starting on a road surface with an extremely low coefficient of friction, such as on an icy road, or when the vehicle slips during slow acceleration during high-speed driving, the slip rate or its change will be reduced. The driving force can be reduced earlier depending on the magnitude of the . Therefore, it is possible to effectively suppress vehicle slippage when starting on a low friction coefficient road surface and vehicle slippage during slow acceleration during high-speed driving, and it is possible to ensure vehicle running stability in any driving pattern. Effects can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic configuration of the present invention, FIG. 2 is a schematic explanatory diagram showing an embodiment of the invention, and FIGS. 3 and 4 show the processing procedure of the throttle valve control device according to the invention. A flowchart showing an example, FIG. 5 is a graph showing the relationship between the target opening θ0 of the throttle valve and the stroke of the accelerator pedal, and FIG. 6 is a graph showing the relationship between the motor speed and the opening deviation Dir. Ru.

Claims (1)

[Claims] Drive wheel rotation speed detection means for detecting the rotation speed of the drive wheels of the vehicle and outputting the detection signal; non-driving wheel rotation speed detection means for detecting the rotation speed of the non-driving wheels and outputting the detection signal;
A slip ratio calculation means for calculating the slip ratio between the tire and the road surface based on the detection signals from the driving wheel rotation speed detection means and the non-driving wheel rotation speed detection means, and a slip ratio calculation means based on the calculation result of the slip ratio calculation means. slip ratio determining means for determining whether or not is larger than a first set value; change amount calculating means for calculating the amount of change in the slip ratio per predetermined time; a change amount determination means for determining whether the change amount is greater than a second set value based on the determination result of the change amount determination means or the determination result of the slip ratio determination means; A driving force control device for a vehicle, comprising: driving force control means that reduces the driving force when the amount of change is greater than a set value or when the amount of change is greater than a second set value.