JP3407662B2 - Vehicle driving force 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 vehicle driving force control device, and more particularly to a device for obtaining a vehicle driving force corresponding to a gradient of a traveling road.

[0002]

2. Description of the Related Art Conventionally, there has been one in which, for example, a shift characteristic is controlled so as to obtain an optimum characteristic according to the gradient of a traveling road (Japanese Patent Publication No. 59-8698, Japanese Patent Laid-Open No. 8-9898). 219242). Is to determine whether the road is a flat road or an uphill road by switching the shift map, or continuously correcting the gear ratio according to the slope of the road surface during uphill traveling so that the acceleration does not become dull due to the slope. Is.

[0003]

However, since there is no relation between the driving force obtained based on the gear ratio corrected according to the gradient and the driving force actually expected by the driver, The driving force obtained based on the gear ratio corrected according to the gradient may cause the driver to feel excessive acceleration or vice versa.

On the other hand, in the case of (1), it is conceivable to match the shift map for the uphill road so that the driving force expected by the driver can be obtained on the uphill road. However, if the shift map for the uphill road is adapted with the gradient that changes variously as a parameter, not only the memory capacity is increased, but also the number of man-hours for the adaptation becomes enormous.

When the driving force is corrected by the throttle opening control instead of the gear ratio control, the throttle opening is moved regardless of the accelerator operation amount of the driver, so that the suction negative pressure changes. , This negative pressure change causes discomfort in the sole of the foot. For example, if you try to increase the driving force by opening the throttle opening even though the accelerator pedal is pressed at a substantially constant amount, the accelerator pedal feels a little far away, and you should close the throttle opening to reduce the driving force. Then, it feels like kickback.

If the driving force is corrected by controlling the throttle opening, the number of opportunities to drive the throttle increases.
Throttle durability is reduced.

Therefore, in the present invention, the driving force characteristic for a flat road is determined in advance so that the driver can obtain a satisfactory acceleration feeling on a flat road, so that the driver can obtain a satisfactory acceleration feeling even on an uphill road. By adjusting the correction driving force with respect to the driving force characteristics for a flat road and performing the driving force correction by the shift control of the continuously variable transmission, the flatness of the flat road can be increased without increasing the memory capacity and the adaptation man-hour. In addition to ensuring a consistent feeling of acceleration regardless of the climbing road, and preventing the feeling of discomfort on the sole of the foot,
The purpose is to prevent deterioration of throttle durability.

[0008]

A first invention is shown in FIG.
As described above, the means 1 for detecting the accelerator operation amount and the vehicle speed
Degree Detecting Means 2 and Accelerator Operation Detected These
Target input of continuously variable transmission on flat road according to quantity and vehicle speed
Rotation speed is normal target input rotation speed tNin means to set as n
3 and means 4 for detecting the weight gradient resistance (force) RFORCE
The detected weight gradient resistance RFORCE of
The driving force correction amount ΔRFORCE less than
Normal target input speed tNin Vehicle driving force at n tTd add to n
Target driving force tTd cNoboru
On the slope road regardless of the slopeThis target driving force corresponding to the gradient tT
d The target input speed that c occurs is the target input speed corresponding to the gradient.
Means 5 for calculating as the number tNin and the calculated gradient pair
A way to achieve the target input speed tNin using a continuously variable transmission
And step 6.

As shown in FIG. 10, a second aspect of the present invention is a means 1 for detecting an accelerator operation amount, a means 2 for detecting a vehicle speed, and a flat road according to the detected accelerator operation amount and the vehicle speed. The target driving force of the vehicle at the normal target driving force tT
d Means 121 to calculate as n and weight gradient resistance (force) RFORCE
Means 4 for detecting, and the detected weight gradient resistance RFOR
With CE as 100%, the means 122 for calculating the driving force correction amount ΔRFORCE of less than this and the ascending grade road
Is the calculated driving force correction amount ΔRFORCE regardless of the gradient
Is the normal target driving force tTd The target driving force tTd corresponding to the gradient is the value added to n When the means 123 for calculating as c and the detected accelerator operation amount and vehicle speed are used, the calculated target driving force tTd corresponding to the gradient is calculated. The means 124 for calculating the target input speed of the continuously variable transmission, which is generated as c, as the gradient-corresponding target input speed tNin, and the calculated slope-corresponding target input speed tNi.
and n for realizing n using a continuously variable transmission.

In a third aspect of the invention, in the second aspect, the calculation by the gradient-corresponding target input revolution number calculating means 124 corresponds to the detected accelerator operation amount from a plurality of maps provided for each accelerator operation amount. By selecting the map to be searched and searching the selected map, the target input speed corresponding to the detected vehicle speed and the calculated slope-corresponding target driving force can be obtained as the slope-corresponding target input speed. is there.

In a fourth invention, in the second or third invention, the driving force correction amount ΔRFORCE is the weight gradient resistance.
30% to 70% of the size of RFORCE.

In a fifth aspect of the present invention, the ratio of the driving force correction amount ΔRFORCE to the weight gradient resistance RFORCE in the second or third aspect is a value that decreases as the weight gradient resistance RFORCE increases.

As shown in FIG. 11, a sixth aspect of the present invention is a means 1 for detecting an accelerator operation amount, a means 2 for detecting a vehicle speed, and a flat road corresponding to the detected accelerator operation amount and the vehicle speed. The target input speed of the continuously variable transmission at the normal target input speed tNin Means 3 to set as n and a predetermined weight gradient resistance RFORCE which is not a flat road If S is 100%, the value of the percentage less than this is the target driving force tTd of the vehicle on a flat road. The target drive force corresponding to the value added to n is the reference drive force tTd corresponding to the gradient. When set to up, this gradient-corresponding reference target driving force tTd The target input speed of the continuously variable transmission that can obtain up is the reference target input speed tNin corresponding to the gradient. means 131 for setting as up, means 4 for detecting the weight gradient resistance (force) RFORCE, the detected weight gradient resistance RFORCE and the predetermined weight gradient resistance RFORCE A means 132 for calculating an interpolation coefficient β0 from S and the gradient-corresponding reference target input speed tNin using this interpolation coefficient β0. up and the normal target input speed tNin
A means 133 for calculating a value obtained by interpolating and calculating n as a gradient-corresponding target input rotational speed tNin and a means 6 for realizing the calculated gradient-corresponding target input rotational speed tNin using a continuously variable transmission are provided.

In a seventh aspect of the present invention, in any one of the first to sixth aspects of the invention, the means 4 for detecting the weight gradient resistance is means for detecting an absolute position of the vehicle, and the vehicle based on the detected value. And a means for estimating the weight gradient resistance from the estimated road gradient and means for estimating the gradient of the road on which the road exists.

In an eighth aspect of the present invention, in any one of the first to sixth aspects of the present invention, the means 4 for detecting the weight gradient resistance is a means for calculating a drive shaft rotational force, and a flattening according to the vehicle speed. A means for calculating a reference running resistance on the road as a reference running resistance; a means for detecting the acceleration of the vehicle; a means for estimating the acceleration resistance (force) of the vehicle based on the detected acceleration; And means for estimating a value obtained by subtracting the reference running resistance and the acceleration resistance from the generated drive shaft rotational force as the weight gradient resistance.

[0016]

According to the first aspect of the invention, the normal target input speed is set so that the control can be performed on a flat road in a speed change pattern in which economy is prioritized. By calculating each driving force correction amount so that the feeling can be obtained, a comfortable feeling of acceleration can be obtained even on an uphill road, and the driving force correction can be performed only by the shift control of the continuously variable transmission. Since the throttle opening control need not be used for the following, the following effects are obtained.

That is, when the driving force is corrected by controlling the throttle opening, the suction negative pressure changes because the throttle opening is moved regardless of the accelerator operation amount of the driver. According to the first aspect of the invention, when the driver's accelerator operation amount is constant, a constant throttle opening can be maintained in response to this, so that a foot pressure change due to a change in negative pressure is caused. There is no such discomfort behind. Further, as compared with the case where the driving force is corrected by controlling the throttle opening, the opportunity to drive the throttle is reduced, which is also advantageous in terms of throttle durability. As a result, a smooth and comfortable feeling of acceleration can be obtained according to a wide range of accelerator operation amount, vehicle speed, and weight gradient resistance.

Also in the second and third inventions, the target driving force on a flat road can be obtained by only having one coefficient for the weight gradient resistance.
Since the (normal target driving force) can be converted into a target driving force corresponding to the gradient, it is not necessary to have a target map different from usual such as a high output mode that corresponds to the gradient unlike the conventional device, and
It is possible to prevent an increase in M capacity and an increase in matching man-hours. In addition, the characteristic tuning can be easily performed by changing the gradient resistance coefficient, and, like the first invention, compared to the case where the driving force correction is performed by controlling the throttle opening, the sole of the foot due to the change of the negative pressure is changed. There is no sense of discomfort.

According to the fourth aspect of the invention, the driving force correction can be assisted most comfortably when traveling uphill, so that not only does the vehicle not feel insufficient acceleration or a sense of tension when traveling uphill,
You can always get a natural feeling of acceleration.

According to the fifth aspect of the present invention, it is possible to produce a natural sense of acceleration while always reducing the driver's discomfort no matter how the gradient changes.

In the sixth aspect of the present invention, since the means for presetting the gradient-corresponding reference target input rotational speed is provided, it is possible to easily carry out preparation for various constraint conditions. For example, it is possible to set the gradient-corresponding reference target input speed so that the input speed does not accelerate the wear of the transmission depending on the load. In addition, for example, by setting a reference target input speed that corresponds to a gradient that is smaller than the target input speed in another driving range (Tatoba Sport mode), you can accelerate regardless of the driver's intention when switching to sports mode. You can avoid doing and slowing down. Alternatively, it is possible to always change to the acceleration side as expected by the driver.

According to the seventh aspect of the invention, since the road gradient at the position where the vehicle exists can be estimated based on the map information and the absolute position information from the satellite, which is held in advance, driving due to changes in the vehicle state such as tire puncture and deterioration over time. The road gradient can always be accurately detected without being affected by changes in force characteristics. In addition, it is possible to estimate not only the roads that currently exist but also the roads that are planned to travel ahead, so it is possible to read the slope ahead of time and correct the driving force. It becomes possible to correct the driving force.

In the eighth invention, it is not necessary to provide a new sensor for detecting the weight gradient resistance, so that the weight gradient resistance can be estimated very inexpensively.

[0024]

1 is a block diagram of the entire control system.

The output of the engine 101 is transmitted to drive wheels (not shown) via an automatic transmission 103 with a built-in torque converter. The automatic transmission here is a continuously variable transmission such as a V-belt type or a toroidal type.

In the intake passage of the engine 101, a so-called electronically controlled throttle device 102 for opening / closing a throttle valve by a motor or the like is interposed, and the amount of air taken into the engine 101 is adjusted by the opening of the throttle valve. , The output torque of the engine is controlled.

In order to drive the electronically controlled throttle device 102, a throttle control module (hereinafter TC
M) 51. The TCM51, which receives the throttle valve opening command from the powertrain control module (PCM) 50, converts the throttle valve opening command to a motor drive voltage and outputs it to the motor, and the actual throttle valve opening is PCM50. The motor drive voltage (throttle valve opening) is feedback-controlled so as to coincide with the opening command from.

An accelerator operation amount signal from the accelerator operation amount (accelerator pedal depression amount) sensor 105, a brake operation signal from the brake operation switch 106, a select range signal from the range selection lever 107 of the automatic transmission, etc. are input. In the PCM50, based on these signals, engine control (for example, mainly control of the fuel supply amount to the engine 101 and ignition timing), automatic transmission control (gear position control to the automatic transmission 103, hydraulic control), braking force Each control of control (brake hydraulic pressure control to the brake actuator 104 for each wheel) is performed.

On the other hand, 111 is a camera for photographing the situation in front of the vehicle as an image. The signal from the camera 111 is used by the image processing device 53 for the road situation in front and the vehicle situation.
It is processed as obstacle information and the like and transmitted to the external environment information processing module 52.

Reference numeral 113 denotes a GPS antenna 113 which receives a signal from a satellite, and the information from the satellite is transmitted to the position information processing device 54 in order to grasp the current position of the vehicle. Map information that incorporates geographical attributes and road information in advance
In the position information processing device 54 stored as a recording medium such as a CD-ROM, the external environment information processing module 52 collects the information of the region currently existing from this information and the signal from the GPS antenna 113. Send to.

In the external environment information processing module 52, the current environment of the vehicle is appropriately collected and transmitted to the PCM 50, and the PCM 50 receives this signal and controls the output of the engine 101 and the shift of the automatic transmission 103. To do. On the contrary, PCM50
The output torque information of the engine 101, the gear position information of the automatic transmission 103, the signal state from the accelerator opening sensor 105, the brake operation switch 106, and the like are transmitted to the external environment information processing module 52. In the external environment information processing module 52,
When receiving this signal, the accuracy of the judgment of the external environment may be improved, or the psychological state of the driver may be estimated.

In the first embodiment of the present invention, the target driving force for a flat road is set in advance as a normal target driving force so that the driver can obtain a satisfactory acceleration feeling on a flat road. In order to obtain a satisfactory acceleration feeling, the correction driving force is adjusted with respect to the normal target driving force, and the driving force correction is performed by the shift control of the continuously variable transmission.

This control performed by the PCM 50 will be described with reference to the block diagram of FIG.

In the normal target driving force setting means 12 to which the accelerator operation amount APO detected by the accelerator operation amount sensor 105 and the vehicle speed VSP detected by the vehicle speed detecting means 11 are input, according to these values. , The target value of the vehicle driving force when traveling on a flat road is the normal target driving force tTd Set as n.

The gradient-corresponding target driving force calculating means 15 comprises a driving force correction amount calculating means (comprising multiplying means) 16 and a driving force correcting means (comprising adding means) 17. The weight gradient resistance RFORCE detected by the weight gradient resistance detection means 14 is input to the driving force correction amount calculation means 16, and this weight gradient resistance RFORCE is input.
The driving force correction amount ΔRFORCE (= α × RFORCE) is obtained by multiplying CE by the gradient resistance coefficient α (where 0 <α <1), and the value of the correction amount ΔRFORCE is calculated by the driving force correction means 17 as described above. Target driving force tTd It is added to n and the target driving force corresponding to the gradient tTd (= tTd n + ΔRFORCE) is calculated.

The normal target driving force tTd is set so that the driver can obtain a satisfactory acceleration feeling on a flat road. By calculating n and the driving force correction amount ΔRFORCE so that the driver can obtain a feeling of acceleration that is satisfactory on the uphill road,
You can always feel a good sense of acceleration regardless of whether you are on a flat road or an uphill road.

In this case, since the target driving force on a flat road can be converted into the target driving force corresponding to the gradient by only having one gradient resistance coefficient α for the weight gradient resistance RFORCE, it is possible to cope with the gradient like the conventional device. It is not necessary to have an unusual target map such as a certain high output mode, and it is possible to prevent the ROM capacity from increasing. Further, it is possible to easily perform characteristic tuning by changing the gradient resistance coefficient.

Gradient corresponding target driving force tT thus obtained
d The gradient-corresponding target input rotation speed calculation means 18 to which c, the accelerator operation amount APO, and the vehicle speed VSP are inputted is provided with a plurality of gradient-corresponding target input rotation speed maps for each accelerator operation amount (represented by 4 sheets in the figure). ) Is provided, and the vehicle speed VSP and the target driving force tTd corresponding to the gradient are included in the target input speed map corresponding to each gradient.
Data of the target input speed of the continuously variable transmission, which has c and c as parameters, is stored as the slope-corresponding target input speed. Thus, the gradient-corresponding target input revolution speed Starring Sante stage 18, the gradient corresponding target input rotation speed map to suit the accelerator operation amount APO at that time is selected by searching the map, the corresponding target driving gradient at that time Force tTd Target input speed tNin corresponding to gradient corresponding to c and vehicle speed VSP c is required.

FIG. 3 is a flow chart constructed corresponding to the block diagram of FIG.

Although there are some parts that overlap with those described with reference to FIG. 2, regardless of the description, FIG.
Execute every 10 msec.

In step 1, the accelerator operation amount APO, the vehicle
Load both speed VSP, weight gradient resistance RFORCE, out of which
Normal target drive according to accelerator operation amount APO and vehicle speed VSP
Force tTd Set n in step 2. Where the normal eye
Target driving force tTd n is the vehicle driving force index when driving on a flat road.
It is a standard price.

In step 3, the weight gradient resistance RFORCE is multiplied by a gradient resistance coefficient α (where 0 <α <1) to obtain a driving force correction amount ΔRFORCE (= α × RFORCE), and this value ΔRFORCE is calculated in step 4 above. Normal target driving force tTd By adding to n, the target driving force tTd corresponding to the gradient c (= tTd n +
Calculate ΔRFORCE).

At step 5, the target driving force tT corresponding to this gradient is obtained.
d Target driving force tTd corresponding to gradient by map search, etc. from c, accelerator operation amount APO, vehicle speed VSP The target input rotation speed tNin corresponding to the gradient of c is obtained.

As described above, in the first embodiment, the driving force characteristics for a flat road are set in advance so that the driver can obtain a satisfactory acceleration feeling on a flat road, and the acceleration feeling that the driver can satisfy on an uphill road as well. Since the correction driving force is adjusted with respect to the driving force characteristics for the flat road so that
In addition to always providing a feeling of acceleration that does not cause discomfort regardless of the climbing grade road, the driving force correction is performed by the shift control of the continuously variable transmission, so that the following effects are obtained.

That is, when the driving force is corrected by controlling the throttle opening, the suction negative pressure changes because the throttle opening is moved regardless of the accelerator operation amount of the driver. Although there is a feeling of strangeness, according to the first embodiment, when the accelerator operation amount of the driver is constant, it is possible to maintain a constant throttle opening corresponding to the accelerator operation amount. There is no such discomfort behind. Further, as compared with the case where the driving force is corrected by controlling the throttle opening, the opportunity to drive the throttle is reduced, which is also advantageous in terms of throttle durability. As a result, a smooth and comfortable feeling of acceleration can be obtained according to a wide range of accelerator operation amount, vehicle speed, and weight gradient resistance.

FIG. 4 shows the gradient resistance coefficient calculating means 31 of the second embodiment.

In the first embodiment, the gradient resistance coefficient α has a constant value, whereas in the second embodiment, the gradient resistance coefficient α is a function of the weight gradient resistance RFORCE, that is, the weight gradient resistance RF.
It is made smaller as the ORCE becomes larger.

Here, the greater the weight gradient resistance, the more α
The value of is made smaller because the driver recognizes the gradient more strongly as the weight gradient resistance increases. That is, when the grade is gentle, the driver does not notice the grade very much, so the amount of accelerator operation does not change much from that on a flat road, so unless the ratio of the driving force correction amount ΔRFORCE to the weight gradient resistance is increased, insufficient acceleration is felt. I tend to. On the other hand, as the gradient becomes larger, the driver recognizes the gradient and deliberately depresses the accelerator pedal deeply.Therefore, even if the ratio of the driving force correction amount ΔRFORCE to the weight gradient resistance is small compared to a gentle gradient, the driver accelerates. Never feel short. Therefore, if α is given so that the ratio of the driving force correction amount ΔRFORCE to the weight gradient resistance becomes smaller as the weight gradient resistance becomes larger, no matter how the gradient changes, the driver will feel less discomfort. , Can always produce a natural sense of acceleration.

Further, the gradient resistance coefficient α is varied between 30% and 70% because the driving force correction can be assisted most comfortably when traveling uphill is 30% of the weight gradient resistance.
This is because the range is up to 70%. As a result, not only does the vehicle not feel insufficient acceleration or a sense of tension when traveling uphill, but it also provides a natural feeling of acceleration.

FIGS. 5 and 6 show a third embodiment, which replaces FIGS. 2 and 3 of the first embodiment, respectively. Figure 5
2 are designated by the same reference numerals, and in FIG. 6, the same portions as those in FIG. 3 are designated by the same step numbers.

In the normal target input speed setting means 41 to which the accelerator operation amount APO detected by the accelerator operation amount sensor 105 and the VSP detected by the vehicle speed detecting means 11 are input, according to these values, The input speed target value of the continuously variable transmission when traveling on a flat road is the normal target input speed tNin Set as n.

The gradient-corresponding target input rotation speed calculating means 42 comprises a gradient-corresponding reference target input rotation speed setting means 43, a dividing means 44, and a target input rotation speed interpolation calculating means 45.

Of these, the gradient-corresponding reference target input rotation speed setting means 43 retrieves a predetermined map from the accelerator operation amount APO and the vehicle speed VSP to obtain the gradient-correspondence reference target input rotation speed tNin. up is required. Here, the slope-corresponding reference target input speed tNin up is the normal target input speed tNin
For n, considering the output torque characteristics of the engine,

[0054]

[Equation 1] Driving force [tNin up, APO, VSP] = driving force [tNin
n, APO, VSP] + α × RFORCE S However, RFORCE S: Predetermined so as to satisfy the relational expression of a predetermined weight gradient resistance.

Here, the driving force of the equation 1 [tNin n, APO, V
SP] is the input speed of the transmission (tNin n), accelerator operation
From the amount (APO) and vehicle speed (VSP), the driving force of the vehicle is
It means that it is decided.

More specifically, the first term on the right side of the equation (1) is
tNin Driving force determined from n, APO, VSP, that is, the normal target driving force tTd of the first embodiment It is n. On the other hand, the driving force on the left side is the reference target driving force tTd corresponding to the gradient. If you say up, this gradient-based reference target driving force tTd up is a predetermined weight gradient resistance RFORCE which is not a flat road When S is 100%, the value of the percentage less than this is the normal target driving force tTd n
The target driving force corresponds to the value added to. Such a gradient-corresponding reference target driving force tTd The target input speed of the continuously variable transmission that is predetermined so that up can be obtained is the reference target input speed tNin corresponding to the gradient. up.

On the other hand, in the dividing means 44, the weight gradient resistance RFOR
CE (detection value) is the prescribed weight gradient resistance RFORCE Divide by S
By that

[0058]

[Equation 2] β0 = RFORCE / RFORCE The interpolation coefficient β0 (dimensionless number) is calculated by the formula of S, and the interpolation coefficient β0 and the above two target input speeds tNin n, tNin
Using up, in the target input speed interpolation calculation means 45,

[0059]

[Formula 3] tNin = β0 × tNin up + (1-β0) × tNin The target input rotational speed tNin corresponding to the gradient is obtained by the interpolation calculation formula of n.

FIG. 6 is a flowchart configured corresponding to FIG. 6 are different from FIG. 3 in steps 11, 12, 13, and 14.

Here again, there is a portion overlapping with that described with reference to FIG.
12, the normal target input speed tNin corresponding to the accelerator operation amount APO and the vehicle speed VSP n and gradient-corresponding reference target input speed tN
in Set up respectively.

In step 13, the weight gradient resistance RFORCE (test
Value) and the prescribed weight gradient resistance RFORCE Formula 2 above from S
Calculate the interpolation coefficient β0 by using the interpolation coefficient β0
In Step 33, the gradient-adaptive target entry is performed according to the above equation (3).
Calculate force rotation tNin.

As described above, in the third embodiment, the gradient-corresponding reference target input rotational speed tNin Since it has a means for setting up in advance, it is possible to easily create it for various constraint conditions. For example, it is possible to set the gradient-corresponding reference target input speed so that the input speed does not accelerate the wear of the transmission depending on the load. In addition, for example, by setting a reference target input speed that corresponds to a gradient that is smaller than the target input speed in another driving range (Tatoba Sport mode), you can accelerate regardless of the driver's intention when switching to sports mode. You can avoid doing and slowing down. Alternatively, it is possible to always change to the acceleration side as expected by the driver.

FIG. 7 shows a fourth embodiment, which shows a method for estimating the gradient of the road surface from the map data including the altitude.

Consider estimating the slope of the road at the position of the vehicle 71 shown in FIG. In this case,
If the map information is divided into grids as shown in the figure and the elevation data of each grid point (indicated by black circles) is stored,
Using the elevation data (a, b, c, d) of the four grids of the section in which 71 exists, the average gradients in the X-axis direction and the Y-axis direction of that section are

[0066]

## EQU00004 ## Average gradient in X-axis direction = (d-b + ca) / 2L Average gradient in Y-axis direction = (a-b + cd) / 2L However, since it is given by the formula of L: lattice spacing, If the vehicle 71 is traveling counterclockwise with respect to the X-axis direction in the direction of the angle ξ,

[0067]

[Formula 5] tan Θ = {(d-b + ca) / 2L} × cos ξ + {(a-b + c-
The road gradient Θ at the position where the vehicle 71 exists can be obtained from the expression d) / 2L} × sin ξ.

From this road gradient Θ to the weight gradient resistance RF
To obtain the ORCE, refer to Japanese Patent Application Laid-Open No. 8-219242

[0069]

[Formula 6] RFORCE = m × g × sin Θ However, m: vehicle weight g: Gravity acceleration The following equation may be used.

Here, the case of the map information in which the elevation data is stored in a grid pattern has been described, but the present invention is not limited to this, and the elevation data may be stored at a point on the road or the inclination of the road. It is also possible to estimate the road gradient by storing the value at a point on the road.

As described above, in the fourth embodiment, the road gradient at the position where the vehicle exists is estimated based on the map information that is held in advance and the absolute position information from the satellite or the like. The road gradient can be accurately detected without being affected by changes in driving force characteristics due to changes in vehicle conditions.

Further, not only the existing roads but also the slopes of the roads to be traveled ahead can be estimated, so that the driving force can be corrected by pre-reading the slopes, and the driver can further respond. It is possible to correct the driving force with good performance. Normally, even if an attempt is made to estimate the road gradient from the output, driving force, vehicle acceleration, etc., it will not completely match the actual gradient (that is, there will be a deviation) due to calculation delays or vehicle driving force transmission delays. This gap can be avoided by reading ahead.

FIG. 8 shows a fifth embodiment, in which the drive shaft rotational force is calculated, and the weight running resistance is estimated by adding the reference running resistance and the acceleration resistance on a flat road. It is a thing.

First, the drive shaft torque calculating means 81 is mainly composed of an engine output shaft torque calculating means 82, a torque converter torque amplification ratio calculating means 83, and a drive system loss torque estimating means 84. Of these, in the engine output shaft torque calculation means 82, the engine fuel injection amount Tp and the engine speed EN
The output shaft torque Te of the engine is obtained by searching a predetermined map from GREV. In the torque amplification ratio calculation means 83 of the torque converter, the ratio between the engine speed ENGREV and the transmission input shaft speed INPREV (output shaft speed of the torque converter) is calculated as the gear ratio SLPRTO, and a predetermined map is calculated from this value. By searching,
The torque amplification ratio TAURTO of the torque converter is required.
The drive system loss torque estimating means 84 obtains the loss torque LOSSTRQ by searching a predetermined map from the operating oil pressure TGTPRS that has the largest influence on the drive system loss torque.

In the multiplication means 85, the output shaft torque of the engine
Te is multiplied by the torque amplification ratio TAURTO of the torque converter to obtain the primary shaft output torque Tin (= Te × TAURTO), and the multiplication means 86 and the addition means 87

[0076]

[Equation 7] Tsec = Tin × RATIO−LOSSTRQ However, the output shaft torque (= driving shaft rotational force) Tsec of the drive shaft is calculated by the formula of RATIO: input / output speed ratio of the transmission.

On the other hand, the reference running resistance calculation means 91 searches for a predetermined map from the vehicle speed VSP to determine the reference running resistance (reference running resistance on a flat road) RLDT.
RQ is required.

The acceleration detecting means 92 obtains the vehicle acceleration GDATA from the difference of the vehicle speed VSP, and the acceleration resistance estimating means 9
In 3, the estimated acceleration resistance AccTRQ on the output shaft is obtained by multiplying the vehicle acceleration GDATA by the equivalent weight Iv of the vehicle viewed from the output shaft.

The output shaft torque Tsec of the drive shaft, the reference running resistance RLDTRQ, and the estimated acceleration resistance thus obtained are obtained.
Using AccTRQ, in the weight gradient resistance estimating means 94,

[0080]

[Formula 8] RFORCE = Tsec-RLDTRQ-AccTRQ The weight gradient resistance RFORCE is calculated by the following equation.

Although the vehicle acceleration is estimated from the vehicle speed in FIG. 9, the vehicle acceleration may be directly detected by the acceleration sensor.

As described above, in the fifth embodiment, it is not necessary to provide a new sensor for detecting the weight gradient resistance, so that the weight gradient resistance can be estimated very inexpensively.

In the embodiment, the case where the continuously variable transmission is controlled with the input speed of the continuously variable transmission as the target value has been described.
The gear ratio of the continuously variable transmission has a value equivalent to the input speed, and the continuously variable transmission may be controlled using this gear ratio as a target value.

[Brief description of drawings]

FIG. 1 is a control system diagram of the entire vehicle of the present invention.

FIG. 2 is a block diagram showing processing performed by PCM50.

FIG. 3 is a flowchart corresponding to the block diagram of FIG.

FIG. 4 is a block diagram of a second embodiment.

FIG. 5 is a block diagram showing processing performed by a PCM 50 according to a third embodiment.

FIG. 6 is a flowchart corresponding to the block diagram of FIG.

FIG. 7 is a road map for explaining a road gradient calculation according to the fourth embodiment.

FIG. 8 is a block diagram of a fifth embodiment.

FIG. 9 is a diagram corresponding to the claims of the first invention.

FIG. 10 is a diagram corresponding to a claim of the second invention.

FIG. 11 is a diagram corresponding to a claim of the sixth invention.

[Explanation of symbols]

12 Normal target driving force calculation means 15 Target driving force calculation means for slope 16 Driving force correction amount calculation means 18 Target input speed calculation means for slope 31 Gradient resistance coefficient calculation means 41 Normal target input speed setting calculation means 43 Grade Corresponding Reference Target Input Rotation Speed Setting Means 44 division means 45 Target Input Revolution Interpolation Calculation Means 50 PCM

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hiroro Nishijima 2 Takara-cho, Kanagawa-ku, Yokohama, Kanagawa Nissan Motor Co., Ltd. (56) Reference JP-A-61-119856 (JP, A) JP-A-8- 68448 (JP, A) JP 9-229173 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (8)

(57) [Claims] 1. A means for detecting an accelerator operation amount, a means for detecting a vehicle speed, and a target input rotation speed of a continuously variable transmission on a flat road according to the detected accelerator operation amount and the vehicle speed A means for setting the target input rotation speed, a means for detecting the weight gradient resistance, and a driving force correction amount of less than 100% based on the detected weight gradient resistance as the vehicle drive at the normal target input rotation speed. When the driving force added to the force is used as the gradient-corresponding target driving force, means for calculating the target input rotational speed at which the gradient-corresponding target driving force is generated as the gradient-corresponding target input rotational speed on the climbing grade road , And a means for realizing the calculated target input rotational speed corresponding to the gradient by using a continuously variable transmission. 2. A means for detecting an accelerator operation amount, a means for detecting a vehicle speed, and a target driving force of a vehicle on a flat road corresponding to the detected accelerator operation amount and the vehicle speed, as a normal target driving force. A means for calculating, a means for detecting the weight gradient resistance, a means for calculating a driving force correction amount of less than this with the detected weight gradient resistance as 100%, and this calculation for climbing grade roads regardless of the gradient. Means for calculating a value obtained by adding the calculated driving force correction amount to the normal target driving force as a gradient-corresponding target driving force, and the calculated gradient-corresponding target driving force at the detected accelerator operation amount and vehicle speed Means for calculating the target input rotation speed of the continuously variable transmission as a gradient-corresponding target input rotation speed, and realizing the calculated gradient-corresponding target input rotation speed by using the continuously variable transmission. And a vehicle driving force control device. 3. The calculation in the gradient-corresponding target input rotational speed calculating means selects a map corresponding to the detected accelerator operation amount from a plurality of maps provided for each accelerator operation amount, and the selected map. The target input rotational speed corresponding to the detected vehicle speed and the calculated gradient-corresponding target driving force is obtained as a gradient-corresponding target input rotational speed by searching for The vehicle driving force control device described. 4. The vehicle drive force control device according to claim 2, wherein the drive force correction amount is 30% to 70% of the magnitude of the weight gradient resistance. 5. The vehicle driving force control device according to claim 2, wherein the ratio of the driving force correction amount to the weight gradient resistance is a value that decreases as the weight gradient resistance increases. . 6. A means for detecting an accelerator operation amount, a means for detecting a vehicle speed, and a target input rotation speed of a continuously variable transmission on a flat road according to the detected accelerator operation amount and the vehicle speed are normally set. A means for setting the target input speed and a target driving force equivalent to a value obtained by adding a percentage value less than this to the target driving force of the vehicle on a flat road with 100% as a predetermined weight gradient resistance on a flat road. Means for setting the target input speed of the continuously variable transmission that can obtain the slope-corresponding reference target driving force as the slope-corresponding reference target driving speed, and means for detecting the weight gradient resistance If, means and, with the normal target input rotational said gradient corresponding reference target input rotational speed by using the interpolation coefficients for calculating the interpolation coefficients from said predetermined weight grade resistance and the detected weight grade resistance And a means for calculating a value corresponding to a gradient-corresponding target input rotation speed by means of interpolation calculation, and a means for realizing the calculated slope-corresponding target input rotation speed by using a continuously variable transmission. Driving force control device. 7. The means for detecting the weight gradient resistance includes means for detecting the absolute position of the vehicle, and means for estimating the gradient of the road on which the vehicle is present based on the detected value from map information which has in advance. The vehicle driving force control device according to any one of claims 1 to 6, further comprising means for calculating a weight gradient resistance from the estimated road gradient. 8. A means for detecting the weight gradient resistance, a means for calculating a driving shaft rotational force, a means for calculating a reference running resistance on a flat road according to the vehicle speed as a reference running resistance, A means for detecting the acceleration of the vehicle, a means for estimating the acceleration resistance of the vehicle based on the detected acceleration, a value obtained by subtracting the reference running resistance and the acceleration resistance from the calculated drive shaft rotational force, 7. The vehicle driving force control device according to claim 1, further comprising means for estimating the weight gradient resistance.