JPH0726581B2 - Vehicle drive force control device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vehicle driving force control in which a throttle valve mechanically uncoupled from an accelerator operator is controlled to open and close according to an operation of the accelerator operator. Regarding the device.

(Prior Art) A conventional vehicle driving force control device is disclosed in
The device described in JP-A-60-43133 is known.

This conventional device is a vehicle engine output control device that controls the engine output by changing the fuel supply amount to the engine according to the accelerator pedal position, in a drive wheel rotation speed detection means, a non-drive wheel rotation speed detection means, Calculating means for calculating the slip ratio between the tire and the road surface from the outputs of both detecting means, comparing means for comparing the calculated slip ratio and the set slip ratio, and a control output based on the accelerator pedal position when the calculated slip ratio is large. And a slip ratio control means for outputting a signal for forcibly reducing the fuel supply to the engine.

(Problems to be Solved by the Invention) However, in such a conventional vehicle driving force control device, even if the vehicle running characteristic changes depending on the engine speed or the like, the gear position of the transmission is corrected for the change. However, since the engine driving force is controlled by a unique control characteristic without performing the above, there are the following problems.

For example, even if the optimum driving force is secured when the vehicle is traveling in the high-speed gear position, the gear ratio is changed if the low-speed gear position is selected by the driver (or automatic gear shifting in an automatic vehicle). As a result, the driving force becomes large, which may cause a slip of the driving wheels.

In addition, even if the optimum driving force is secured when traveling in the low speed side gear position, if the high speed side gear position is selected by the driver, etc., the driving force will decrease due to the change of the gear ratio, so the feeling of acceleration is insufficient. May lead to

In addition, when the gear position is constant, in order to maintain the optimum driving force that does not cause the drive wheel slip after the slip prevention control, it is necessary to keep the engine shaft trick constant, and for that purpose, the engine speed fluctuation On the other hand, the throttle opening must be corrected by adjusting the accelerator pedal. For example, in a vehicle having an engine characteristic as shown in FIG. 9, in order to secure an axial torque of 8 kg · m, the throttle opening θ is set to increase or decrease of the engine rotation, It has to be corrected sequentially.

(Means for Solving Problems) The present invention has been made in order to solve the problems described above, that is, to obtain optimum driving,
In order to achieve this object, the present invention has the following solution means.

The solution means of the first invention will be described with reference to the claim correspondence diagram shown in FIG. 1A. An accelerator operation amount detection means a for detecting an accelerator operation amount for an accelerator operator and an actual throttle opening value of a throttle valve are detected. The actual throttle opening value detecting means b, the gear position detecting means c for detecting the gear position of the transmission, and the higher the gear position of the transmission is the higher gear position, the greater the increase ratio of the throttle opening to the accelerator operation amount becomes. Map setting means e for setting an enhanced control characteristic map, target throttle opening value setting means f for obtaining a target throttle opening value based on the control characteristic map set by the map setting means e and the accelerator operation amount, A control signal that causes the actual throttle opening value to match the target throttle opening value is transmitted to the throttle actuator. A throttle valve opening control means h to be output to g, and a means, characterized in that it comprises a.

The solution means of the second invention will be described with reference to the claim correspondence diagram shown in FIG. 1B. An accelerator operation amount detection means a for detecting an accelerator operation amount with respect to an accelerator operator, and an actual throttle opening value of a throttle valve are detected. The actual throttle opening value detecting means b, the engine speed detecting means d for detecting the engine speed, and the higher the engine speed is, the higher the increasing ratio of the throttle opening to the accelerator operation amount is. Map setting means e for setting the control characteristic map, and target throttle opening value setting means f for obtaining the target throttle opening value by the control characteristic map set by the map setting means e and the accelerator operation amount.
And a control signal that causes the actual throttle opening value to match the target throttle opening value.
And a throttle valve opening / closing control means h for outputting to.

(Operation) Therefore, in the vehicle driving force control device of the present invention, when the vehicle is running, the accelerator operation amount is increased as the transmission gear position is set to the higher gear position and the engine rotation speed is set to the higher engine rotation speed. A control characteristic map in which the increase rate (control gain) of the throttle opening is increased is set, and the opening / closing control of the throttle valve corresponding to the accelerator operation is performed based on this control characteristic map.

In this way, the control characteristic map is set by using at least one of the gear position and the engine speed as input information, so that the occurrence of drive wheel slip and the lack of acceleration feeling due to the change of the gear position and the engine speed are prevented. Thus, the optimum engine driving force is secured.

(Examples) Examples of the present invention will be described in detail below with reference to the drawings.

In describing this embodiment, the map setting means inputs signals of both the engine speed and the gear position to determine the increasing ratio of the throttle opening to the accelerator operation amount. As a driving force type, a driving force control device applied to a rear-wheel drive vehicle is taken as an example.

First, the configuration of the embodiment will be described.

As shown in FIG. 2, the power train P of the rear-wheel drive vehicle to which the driving force control apparatus A according to the embodiment is applied includes an engine 10,
It has an automatic transmission 11, a propeller shaft 12, a rear differential 13, rear drive shafts 14 and 15, and rear wheels 16 and 17.

The front wheels 18 and 19 are non-driving wheels.

The driving force control apparatus A of the embodiment mechanically disconnects an accelerator pedal 20 which is an accelerator operator and a throttle valve 22 which is provided in a throttle chamber 21 which is an intake system of the engine 10 from an accelerator control wire or the like. Accelerator pedal 20 and throttle valve instead of the mechanical connection of
22 is a control device provided between the input device and
A rear wheel speed sensor 30, a right front wheel speed sensor 31, a left front wheel speed sensor 32, an accelerator potentiometer 33, a gear position sensor 36, an engine speed sensor 37, and a throttle valve control circuit 34 as an arithmetic processing means. A step motor 35 is provided as a throttle actuator.

The rear wheel rotation speed sensor 30 is a drive wheel speed detecting means, is provided on the input shaft portion of the rear differential 13, and outputs a rear wheel rotation signal (vr) corresponding to the rear wheel rotation speed V _R.

An optical sensor, a magnetic sensor, or the like is used as the rear wheel rotation speed sensor 30, and when a pulse signal is output as the rear wheel rotation signal (vr), the throttle valve control circuit 34
In the input interface circuit 341 inside, the F / V converter converts to a voltage according to the frequency of the pulse signal, and the A / D converter converts the voltage value to a digital value.
342 and memory 343.

The right front wheel rotation speed sensor 31 and the left front wheel rotation speed sensor 32
Is a vehicle speed detecting means, which is provided at each axle portion of the front wheels 18 and 19, and rotates the right front wheel rotation signal (vfr) and the left front wheel rotation according to the right front wheel rotation speed V _FR and the left front wheel rotation speed V _FL. Output signal (vfl).

The signal conversion for the CPU 342 of the throttle valve control circuit 34 to read the output signals from both the front wheel rotation speed sensors 31 and 32 is performed in the same manner as the rear wheel rotation speed sensor 30.

The accelerator potentiometer 33 is a means for detecting the absolute accelerator operation amount 1, is provided at the position of the accelerator pedal 20, and outputs an absolute accelerator operation amount signal (l) corresponding to the absolute accelerator operation amount 1.

Since the output signal from the accelerator potentiometer 33 is an analog signal based on the voltage value, it is converted into a digital value by the A / D converter of the input interface circuit 341 and read into the CPU 342 or the memory 343.

The gear position sensor 36 has a drive range (D range).
When selecting to the automatic transmission
The gear position sensor 36
Outputs a gear position signal (gp) corresponding to each gear position Gp.

Incidentally, in the embodiment, the automatic transmission 11 of the fourth forward speed is applied, and from the gear position sensor 36,
A gear position signal (gp) is output that can identify each of first speed (1st), second speed (2nd), third speed (3rd), and fourth speed (4th).

The engine speed sensor 37 is a means for detecting the speed of the engine 10, and outputs an engine speed signal (ne) corresponding to the engine speed N _E.

The throttle valve control circuit 34 processes the input information from the input sensor and the information temporarily or preliminarily stored in the memory 343 in accordance with a predetermined arithmetic processing procedure and outputs a pulse to the step motor 35 which is a throttle actuator. An electronic circuit centered on a microcomputer that outputs a control signal (c). As internal circuits, an input interface circuit 341, a CPU (central processing unit) 342, a memory (RAM, ROM) 343, and an output interface circuit 344 are provided. I have it.

In setting the region control characteristic map by the throttle valve control circuit 34, the map up-link selection process and the map drop-down selection process are performed first by MAPFLG, and the map corresponding to the number of the MAPFLG selected after both selection processes have passed. select a number, to determine the final map throttle opening maximum M.theta _MAX in this selection was map number (# 0 through # 7) and the gear position Gp to the engine rotational speed N _E, the M.theta _MAX
A region control characteristic map is set based on

The map throttle opening maximum value characteristics of FIGS. 7 (A) to 7 (G) are characteristics experimentally obtained in the gear position D range.

Further, the map numbers # 0 to # 7 correspond to the throttle opening θ that generates the maximum driving force when the road surface friction coefficient μ is set in Table 1 below.

The memory 343 of the throttle valve control circuit 34 stores the third
As shown in the figure, the relationship characteristic between the relative accelerator operation amount Δl and the throttle opening change amount Δθ is set as a cubic curve characteristic.

The throttle valve control circuit 34 includes the slip ratio calculating means, accelerator operation amount detecting means, actual throttle opening value detecting means, map selecting means, map setting means, target throttle opening value setting means described in the claims. A throttle valve opening / closing control means is included.

The actual throttle opening value detecting means receives the STEP command signal from the CPU 342 of the throttle valve control circuit 34 to the output interface circuit 344 in the memory 343 at the same time, and the memory 3
It is a means of an internal circuit configuration for writing and counting the number of STEPs in 43, and the actual throttle opening value θ ₀ is read out to the CPU 342 at any time according to a read command from the CPU 342.

Further, the map selecting means includes a map ascending selecting means and a map dropping selecting means.

The step motor 35 is an actuator that opens and closes the throttle valve 22 and includes a rotor and a plurality of stators having an excitation winding, and a forward rotation direction and a reverse rotation direction depend on how a pulse is applied to the excitation winding. Rotate one step at a time.

Next, the operation of the embodiment will be described.

First, the flow of throttle valve opening / closing control operation in the CPU 342 will be described with reference to the flowchart of the main routine shown in FIG. 4 and the flowchart of the subroutine shown in FIG.

The process in the main routine of FIG. 4 is performed by a not-shown operating system in a predetermined cycle (for example,
2.0 msec) is a constant time interrupt process, and the process in the subroutine of FIG. 5 is appropriately started in the main routine according to the signal output cycle to the step motor 35 determined by this constant time interrupt. Oci (output compare interrupt) interrupt processing.

(A) Initialization The main routine shown in Fig. 4 starts when the engine key is inserted into the key cylinder and the ignition switch is switched from OFF to ON. A determination is made (step 100) and the process proceeds to the next initialization step 101.

In this initialization step 101, MAPFLG
= 0, and clears all other information such as FLG and reference values l ₀₀ and θ ₀₀ .

(B) Slip rate calculation processing The calculation processing of the slip rate S between the tire and the road surface is performed in steps.
Steps 102 to 107 are performed.

First, based on the input signals from the respective rotation speed sensors 30, 31, 32, the rear wheel rotation speed V _R , the right front wheel rotation speed V _FR , the left front wheel rotation speed V
_FL is read (step 102), then front wheel rotation speed V _F
Is calculated (step 103).

The formula for calculating the front wheel rotation speed V _F is V _F = 1/2 (V _FR + V _FL )
And is calculated by the average value.

Next, it is determined whether or not the rear wheel rotation speed V _R, which is the driving wheel, is 40 km / h or more (step 104). If V _R ≧ 40 (km / h), the process proceeds to step 105, and in this step 105 The slip ratio S is calculated.

The calculation formula of the slip ratio S is Is.

When it is determined in step 104 that V _R <40 (km / h), the front-rear wheel rotation speed difference ΔV (= V _R −V _F ) is calculated (step 106) and calculated. The slip ratio S is set according to the front-rear wheel rotation speed difference ΔV (step 107).

Accordingly, the slip ratio S obtained in step 105 or step 107, when expressed in the graph becomes as shown in FIG. 6, the slip ratio S is less the set slip rate control operation of the S _0, S ₁ , the threshold when compared to S _2.

(C) Reading of running state information In step 108, the gear position Gp by the gear position sensor 36 and the engine speed N _E by the engine speed sensor 37 are read as running state information.

(D) Control Information Setting Processing The control information setting processing used in map selection processing and accelerator work determination processing, which will be described later, is performed in steps 150 to 154.

First, sampled at two periods before treatment, the accelerator pedal depression amount that is treated as the last absolute accelerator operation amount l ₁ in the process of one cycle before is set as a second preceding absolute accelerator operation amount l ₂ (step 150).

Further, the accelerator pedal depression amount sampled in the processing one cycle before and treated as the absolute accelerator operation amount l ₀ this time is set as the previous absolute accelerator operation amount l ₁ (step 151).

Next, the current accelerator pedal depression amount is sampled and read as the current absolute accelerator operation amount l ₀ and the current throttle valve opening as the actual throttle opening value θ ₀ (step 152).

Next, by subtracting the previous absolute accelerator operation amount l ₁ from the set current absolute accelerator operation amount l ₀ , 1
Period before the current relative accelerator operation amount [Delta] L ₀ is the change amount of the accelerator pedal depression amount from the time of processing is calculated (step 153), also the second last absolute accelerator operation amount l ₂ is subtracted from the last absolute accelerator operation amount l ₁ As a result, the previous relative accelerator operation amount ΔL ₁ that is the amount of change in the accelerator pedal depression amount that has changed from the processing time two cycles ago to the processing time one cycle ago is calculated (step 154).

(E) Map ascending selection process The map ascending selection process for selecting an upper reference region control characteristic map in which the increase ratio of the throttle opening θ with respect to the absolute accelerator operation amount 1 is higher than the currently selected reference region control characteristic map, Steps 110 to 114 are performed, and steps 110 to 113 are conditions for map ascent. First, this time the relative accelerator operation amount ΔL ₀ is ΔL ₀ <
It is determined whether or not 0, that is, whether or not the accelerator pedal 20 is being depressed (step 110),
Next, it is determined whether or not the slip ratio S is S ≦ S ₀ (for example, S ₀ = 0.1), that is, whether or not the drive wheel slip has occurred at the set slip ratio S ₀ or less (step 111). , Then the actual throttle opening value θ ₀ is θ ₀
It is determined whether ≧ θ _MAX , that is, whether the actual throttle opening value θ ₀ is the throttle opening upper limit value θ _MAX according to the set region control characteristic map (step 112), and whether MAPFLG is MAPFLG = 0. That is, it is determined whether or not the maps are maps # 1 to # 7 that allow map ascent (step 113), and the process proceeds to step 114 only when all of these map ascent conditions are satisfied, and the map FLG number (# 1
To # 7) are lowered by 1 (step 114), and the map moves to the one-step higher map as the reference area control characteristic map.

When any one of the map ascending conditions described in steps 110 to 113 is not satisfied, the reference area control characteristic map selected at that time is held until all the map ascending conditions are newly satisfied. .

(F) Map drop selection process The map drop selection process of selecting a lower reference region control characteristic map in which the increase rate of the throttle opening θ with respect to the absolute accelerator operation amount 1 is lower than the currently selected reference region control characteristic map is This is performed in steps 120 to 131.

First, the slip ratio S and the first set value S ₁ (for example, S ₁ = 0.
1) is compared with, and the upper limit for dropping one map is S> S ₁
It is determined whether or not the drive wheel slip has occurred (step 120). If S> S ₁ , the process proceeds to the next step 121, and it is determined whether FLAG · A = 0 or not, and FLAG · A = If it is 0, FLAG · A = 1 is set (step 122), and in the next step 123, MAPFLG = 7.
It is judged whether or not, and when MAPFLG ≠ 7, the condition for dropping one map (S> S ₁ and MAPFLG ≠ 7) is satisfied.
The MAPFLG number (# 0 to # 6) is increased by 1 (step
124), and shifts to a map one step lower as the reference area control characteristic map.

After dropping one map in step 124,
In step 120, it is determined that S ≦ S ₁ , FLAG · A = 0 is set after step 125, and unless S> S ₁ is newly established, the selection process of dropping one map is not performed,
The reference region control characteristic map selected by dropping one map in step 124 is held as it is.

However, when FLAG · A = 1, step 121 to step 1
The process proceeds to step 26, and the case where the condition of S> S _{2 to be} described later that satisfies the map dropping condition is satisfied is different.

In addition, when proceeding from the step 124 to the next step 126,
The slip ratio S and the second set value S ₂ (for example, S ₂ = 0.3) are compared, and whether S> S ₂ which is the condition for dropping one map, that is, whether excessive drive wheel slip has occurred If S> S ₂ , the process proceeds to the next step 127, and it is determined whether FLAG · B = 0. If FLAG · B = 0, FLAG · B = 1 is set (step 12
8) In the next step 129, it is determined whether or not MAPFLG = 7. When MAPFLG ≠ 7, the condition of dropping one map (S> S ₂ and MAPFLG ≠ 7) is satisfied, and thus the number of MAPFLG ( #
0 to # 6) is incremented by 1 (step 130), and the map moves to the map one step lower as the reference area control characteristic map.

After dropping one map in step 130,
In step 126, it is determined that S ≦ S _2, and after step 131, FLAG · B = 0 is set, and unless S> S ₂ is newly established, the selection process of dropping one map is not performed.
The reference area control characteristic map selected by dropping one map in step 130 is held as it is.

(G) Setting of area control characteristic map In step 140, the number of MAPFLG ((A) to (G) in FIG. 7) selected by the progress of the above-described map ascending selection processing and map omission selection processing, Step 108
The map throttle opening maximum value Mθ _MAX is determined by the gear position Gp and the engine speed N _E read in.

Then, the line from the map throttle opening maximum M.theta _MAX, as shown in FIG. 8, the map limit, connecting the absolute map throttle opening maximum value of the accelerator operation amount 3/4 M.theta _MAX and zero reference point And the line of the map throttle opening maximum value Mθ _MAX at the absolute accelerator operation amount 3/4 to 4/4, and the map lower limit is formed by the map throttle opening maximum value Mθ _MAX at the absolute accelerator operation amount 4/4. And a zero reference point are connected to each other to finally set an area control characteristic map as shown by the diagonal lines in FIG.

When MAPFLG = 0, the region control characteristic map # 0 shown in FIG. 8 is set regardless of the gear position and engine speed.

Further, as is clear from the characteristics of FIGS. 7 (A) to (G), the map throttle opening maximum value Mθ _MAX becomes higher as the gear position Gp becomes the higher gear position (third speed, fourth speed, etc.). ,
The higher the engine speed N _E is, the higher the map throttle opening maximum value Mθ _MAX becomes, and each map (# 1 to #
Each of 7) will have multiple or infinite maps.

(H) Accelerator Work Discrimination Processing In the accelerator work discrimination processing, since the reference for obtaining the relative accelerator operation amount ΔL is the constant speed traveling accelerator operation, in order to determine whether or not the constant speed traveling accelerator operation is performed, This is the process performed in steps 155 to 159 based on the information obtained in steps 150 to 154.

First, the determination logic of the accelerator work is that the accelerator pedal 20 is being continuously operated in the stepping direction from the time of processing two cycles before using the previous relative accelerator operation amount ΔL ₁ and the current relative accelerator operation amount ΔL _0. When the acceleration accelerator operation determination is made (positive in step 155, affirmative in step 156), or when the deceleration accelerator operation is determined to be subsequently in the returning operation (negative in step 155). , Negative in step 157), proceed to the next step 160.

If the accelerator pedal 20 is stopped and held at that position (negative in step 155, affirmative in step 157), the operating direction of the accelerator pedal 20 is switched from the stepping direction to the returning direction (step 155). Is positive, negative in step 156) or vice versa (negative in step 155, positive in step 157), the change amount of the accelerator pedal depression amount includes 0 from an increase including 0. It is determined that the accelerator is operating at a constant speed that decreases or increases, and the routine proceeds to step 158, where the absolute accelerator operation amount l ₀ is set as the accelerator operation amount reference value l _{00, and the} operation proceeds to step 159. The throttle opening value θ ₀ is set as the throttle opening reference value l ₀₀ .

(I) Relative accelerator stroke calculation processing After the above-described accelerator work determination processing is performed, the routine proceeds to step 160, where the relative accelerator operation amount ΔL is calculated.

The arithmetic expression of this relative accelerator operation amount ΔL is ΔL = l ₀ −l
_Since it is ₀₀ , at the time of acceleration accelerator operation or deceleration accelerator operation, it is calculated as the accelerator operation change amount from the time when the constant speed traveling accelerator operation is first performed to the absolute accelerator operation amount l ₀ this time. Further, at the first constant speed traveling accelerator operation, ΔL = l ₀ −l _{0 and the} relative accelerator operation amount ΔL becomes zero.

(E) Throttle opening change amount calculation In step 170, the sroll opening change amount Δθ is calculated from the relative accelerator operation amount ΔL obtained in step 160 and the ΔL-Δθ characteristic diagram shown in FIG.

(L) Target throttle opening value setting process Temporary target throttle opening value θθ obtained by the throttle opening reference value θ ₀₀ and the throttle opening change amount Δθ calculated in step 170, and set in step 140 Region control characteristic map and absolute accelerator operation amount this time
l ₀ (or accelerator operation amount reference value l ₀₀ ) is compared with the throttle opening upper limit value θ _MAX and the throttle opening lower limit value θ _MIN to set the target throttle opening value θ ^*. It is performed from 180 to step 185.

First, the provisional target throttle opening Shitashita, the arithmetic expression for adding the throttle opening reference value theta ₀₀ and the throttle opening change amount [Delta] [theta] in step 180 is calculated by θθ = θ ₀₀ + Δθ.

The process of comparing the provisional target throttle opening θθ with the throttle opening upper limit value θ _MAX and the throttle opening lower limit value θ _MIN is
First, it is judged whether the provisional target throttle opening value θθ is equal to or more than the throttle opening upper limit value θ _MAX (step 181), and θθ
When> θ _MAX , the throttle opening upper limit value θ _MAX is set as the target throttle opening value θ ^* (step 18
2). If θθ ≤ θ _MAX , it is determined whether the provisional target throttle opening θθ is less than or equal to the throttle opening lower limit value θ _MIN (step 183). If θθ <θ _MIN , the throttle opening lower limit value θ _{MIN is determined.} Is set as the target throttle opening value θ ^* (step 184). Also, θ _MIN ≤ θ θ ≤ θ
_In the case of _MAX , the provisional target throttle opening degree value θθ is set as it is as the target throttle opening degree value θ ^* (step 185).

That is, the target throttle opening degree value θ ^* is set as a value existing within the set region of the region control characteristic map.

(2) Throttle valve opening / closing control process When the target throttle opening value θ ^* is determined by the above-mentioned target throttle opening value setting process, the actual throttle opening value θ
_The processing for operating the throttle valve 22 in the direction in which ₀ coincides with the target throttle opening value θ ^* is performed in steps 200 to 202 in the main routine of FIG. 4 and steps 300 to 304 in the subroutine of FIG. .

First, the deviation ε is calculated by subtracting the actual throttle opening value θ ₀ from the target throttle opening value θ ^* (step 20
0), on the basis of the deviation ε obtained by this calculation, the motor speed of the step motor 35 is calculated, the forward rotation, the reverse rotation, and the holding are determined, and the activation cycle of the oci interrupt routine is obtained (step 201). The oci interrupt routine (FIG. 5) is started according to the operation control contents of the step motor 35 set in 201 (step 202).

Next, a flowchart of the oci interrupt routine will be described with reference to FIG.

First, it is judged whether or not a holding command is output to hold the state of the stepper motor 35 as it is (step 30
0), when the hold command is output, step motor 3
Hold the stator side excitation state of 5 (step 301).

When the hold command is not output, the step motor 35
It is determined whether or not the reverse rotation command for reversing is output (step 302). When the reverse rotation command is output, S
TEP is set to STEP-1 (step 303), and the pulse signal for obtaining STEP-1 is output to the step motor 35 (step 301). Further, at the time of outputting a normal rotation command for rotating the step motor 35 in the normal direction, STEP is set to STEP + 1 (step 304) and a pulse signal for obtaining SETP + 1 is output to the step motor 35 (step 301).

The oci interrupt routine is repeated within the start cycle of the main routine according to the start cycle set in step 201.

As described above, in the driving force control device of the embodiment, the effects listed below can be obtained.

The 1-θ control characteristic map that is set is the area control characteristic map, and the opening / closing control of the throttle opening θ is performed based on the relative accelerator operation amount ΔL based on the absolute accelerator operation amount 1 during constant speed traveling operation. Therefore, the opening / closing control gain of the throttle valve 22 is obtained in accordance with the accelerator work within the map area, and it is possible to secure good vehicle acceleration performance and prevent large changes in vehicle speed during constant-speed traveling operation.

As shown in FIG. 3, the ΔL-Δθ characteristic is a cubic curve characteristic, so that it is possible to prevent a tingling sensation when the accelerator is slightly depressed, and to secure high acceleration when a large amount is depressed. To be done.

As shown in FIG. 6, the slip ratio S is determined by the front-rear wheel rotation speed difference ΔV when the vehicle body speed is low.
Therefore, when the vehicle body speed is low when the slip ratio S changes, high detection accuracy and high calculation accuracy are not required, and map up control and map drop control are not performed by the calculated value of the slip ratio S due to a calculation error.

In the map ascending control of the area control characteristic map, the slip ratio S is S ≦ S ₀ when the accelerator pedal 20 is depressed.
Therefore, the opening of the throttle valve 22 corresponds to the accelerator operation, the driver does not feel uncomfortable, and a natural feeling of acceleration can be obtained.

The map drop control of the area control characteristic map is performed on condition that the slip ratio S is S> S ₁ and FLAG · A = 0. After being dropped, the slip ratio is once S ≦
Even if S ₁ , the lower region control characteristic map is maintained as it is until the map ascending condition is satisfied or the slip ratio S newly exceeds the set slip ratio S ₁ or S ₂ .
Even after avoiding the drive wheel slip, there is no immediate return to the previous drive force level that caused the drive wheel slip,
Re-slip is prevented.

Further, when the set slip ratio S ₁ or S ₂ is newly exceeded, the map is further dropped, and in order to further reduce the drive wheel slip, the throttle opening θ is reduced and the drive force is controlled only in the direction to be reduced. Therefore, there is no hunting due to the increase or decrease of the driving force, and jerky vibration is prevented.

MapFLG number selected by map up control and map drop control, gear position Gp and engine speed N _E
The map throttle opening maximum M.theta _MAX is determined by, as Kawari driving force cut gear position Gp is the low-speed side gear position tries to increase when the vehicle is running at optimal driving force, the direction in which the control gain is reduced The correction of the region control characteristic map suppresses the increase of the driving force and prevents the drive wheels from slipping.On the contrary, when the vehicle is traveling with the optimal driving force, the gear position Gp changes to the high-speed gear position. Even if the switching driving force is about to decrease, the region control characteristic map is corrected in the direction in which the control gain increases, so that the driving force reduction is suppressed and the lack of acceleration feeling is prevented.

Also, when the vehicle is running with a constant gear position, the running resistance changes due to the road surface friction coefficient, slopes, etc.
Even if N _E rises or falls, this engine speed
The region control characteristic map is corrected according to the change in N _E , and the throttle opening is controlled in the direction to keep the shaft torque constant, so the drive can be performed without performing the accelerator operation corresponding to the change in the engine speed N _E. It is possible to prevent wheel slip and lack of acceleration feeling.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and the present invention can be applied even if there is a design change or the like within a range not departing from the gist of the present invention. included.

For example, when setting the control characteristic map only in accordance with the gear position, the average value of the Mθ _MAX values of the engine speed 800 rpm and 5600 rpm at each gear position shown in FIG. 7 is used,
Determine the Z point of the absolute accelerator operation amount 3/4 in Fig. 8. Further, the Z point may be determined using the value of Mθ _MAX of the specific engine speed.

Further, when the control characteristic map is set only according to the engine speed, the average value of Mθ _MAX of the engine speed at each gear position shown in FIG. 7 (for example, indicated by a dotted line in the # 1 map) is set. Using the absolute accelerator operation amount of Fig. 8
Determine the Z point of 3/4.

Further, the Z point may be determined using the value of Mθ _{MAX at} a specific gear position.

Further, in the embodiment, the example in which the area control characteristic map having the upper limit and the lower limit is set is shown, but a linear control characteristic map formed by a straight line, a broken line, a curve, or the like may be set, or only the upper limit is set. An area control characteristic map may be set.

In addition, a plurality of reference control characteristic maps are set in advance,
The drive wheel slip prevention control may be performed by the selection control of the reference control characteristic map, and may be performed by map setting processing for correcting the selected reference control characteristic map in correspondence with the gear position and the engine speed.

Further, in the map drop control, the number of maps to be dropped may be determined according to the degree of increase in the slip ratio, taking into consideration the time change rate of the slip ratio.

Further, in the embodiment, one characteristic is shown as the ΔL-Δθ characteristic. However, for example, when the map # 0 is selected, Δθ based on the characteristic of the solid line is added, as shown by the dotted line in FIG. Is set, and Δθ is set based on the characteristic of the dotted line when the maps # 1 to # 7 are selected. In this case, the range gain of the throttle opening with respect to the absolute accelerator operation amount is traveled. It can be adapted to the road surface condition, and the drive wheel slip can be prevented in advance.

(Effects of the Invention) As described above, in the vehicle driving force control device of the present invention, the higher the gear position is and the higher the gear position is, the higher the gear position of the transmission or the engine speed. Since the map setting means for setting the control characteristic map in which the increase rate of the throttle opening with respect to the accelerator operation amount is increased as the engine speed increases, drive wheel slip caused by changes in the gear position and engine speed is caused. It is possible to prevent the occurrence of driving and the lack of acceleration feeling, and it is possible to obtain the effect of ensuring traveling with an optimum engine driving force.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a claim correspondence diagram showing a vehicle driving force control device of a first invention, and FIG. 1B is a claim correspondence diagram showing a vehicle driving force control device of a second invention, FIG. 2 is an overall view showing a driving force control device of an embodiment of the present invention, and FIG. 3 is a relative accelerator operation amount set in a throttle valve control circuit of the embodiment device.
FIG. 4 is a flow chart showing a main routine of control operation in the throttle valve control circuit of the embodiment, and FIG. 5 is a subroutine of control operation in the throttle valve control circuit of the embodiment. FIG. 6 is a slip ratio threshold value characteristic diagram in the embodiment apparatus, and FIGS. 7A to 7G are map throttle opening maximum values preset in the embodiment apparatus. FIG. 8 is a value characteristic diagram, FIG. 8 is an explanatory diagram of a map setting method in the embodiment apparatus, and FIG. 9 is a shaft torque characteristic diagram with respect to engine speed and throttle opening. a ... Accelerator operation amount detecting means b ... Actual throttle opening value detecting means c ... Gear position detecting means d ... Engine speed detecting means e ... Map setting means f ... Target throttle opening value setting means g ...... Throttle actuator h …… Throttle valve opening / closing control means

Claims (2)

[Claims] 1. An accelerator operation amount detecting means for detecting an accelerator operation amount for an accelerator operator, an actual throttle opening value detecting means for detecting an actual throttle opening value of a throttle valve, and a gear for detecting a gear position of a transmission. Position detecting means, map setting means for setting a control characteristic map in which the increase ratio of the throttle opening to accelerator operation amount is set higher as the gear position of the transmission is the higher gear position, and the map setting means sets the map. Target throttle opening value setting means for obtaining a target throttle opening value based on the control characteristic map and the accelerator operation amount, and a control signal to the throttle actuator for matching the actual throttle opening value with the target throttle opening value. A throttle valve opening / closing control means for outputting to The vehicle driving force control apparatus according to symptoms. 2. An accelerator operation amount detecting means for detecting an accelerator operation amount with respect to an accelerator operator, an actual throttle opening value detecting means for detecting an actual throttle opening value of a throttle valve, and an engine rotation for detecting an engine speed. Number detection means, map setting means for setting a control characteristic map in which the increasing rate of the throttle opening with respect to the accelerator operation amount is increased as the engine speed becomes higher, and the map setting means sets the map. Target throttle opening value setting means for obtaining a target throttle opening value based on the control characteristic map and the accelerator operation amount, and to the throttle actuator a control signal for matching the actual throttle opening value with the target throttle opening value. And a throttle valve opening / closing control means for outputting The control device.