JP2000035117A - Control device for automatic transmission for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the responsiveness of gradient definition and definition accuracy by obtaining the vehicle acceleration with a gradient ascertaining means on the basis of the detected operating condition, and changing a time constant of the data processing to be required for definition on the basis of the obtained vehicle acceleration. SOLUTION: A traveling resistance computing means of an integrated control unit 300 computes the traveling resistance of a vehicle on the basis of the operating condition detected by operating condition detecting means such as a water temperature sensor 106, a throttle opening sensor 108, a brake switch 112, a car speed sensor 122, and a steering sensor 128. A gradient ascertaining means ascertains the gradient of the traveling route on the basis of the traveling resistance and the driving force, and while obtains the vehicle acceleration on the basis of the detected operating condition, and changes a time constant of the data processing to be required for definition on the basis of the obtained vehicle acceleration. With this structure, gradient can be ascertained with high responsiveness and high accuracy, and drivability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an automatic transmission for a vehicle, and more particularly, to estimating a gradient of a traveling road on which a vehicle travels without using a sensor, and based on the estimation result. The present invention relates to an apparatus for controlling a gear ratio.

[0002]

2. Description of the Related Art For example, as disclosed in Japanese Patent Application Laid-Open No. 6-201523, a method of estimating a gradient without using a sensor has been proposed.

In this prior art, the output torque of an engine is calculated using at least one of an engine speed, a throttle opening, an intake air amount, or the like, or the output torque is calculated from an input / output operation formula of a torque converter. The gradient of the traveling road is calculated from the torque value, the differential signal of the vehicle speed, and the flat ground traveling resistance torque.

[0004]

However, in the above technique, it is difficult to achieve both the responsiveness (estimation delay) of the gradient estimation and the estimation accuracy in estimating the gradient. Therefore, the speed ratio is controlled using the estimated gradient. Also, the initial effect could not be sufficiently obtained.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned disadvantages, and to achieve both the responsiveness of the gradient estimation and the estimation accuracy, so that the gear ratio can be optimally controlled and the drivability is improved. It is an object of the present invention to provide a control device for an automatic transmission for a vehicle which is improved.

[0006]

In order to achieve the above object, according to the present invention, there is provided a control system for an automatic transmission for a vehicle, comprising detecting an operating state of a vehicle and an internal combustion engine mounted thereon. Operating state detecting means, running resistance calculating means for calculating running resistance of the vehicle based on the detected operating state, and driving force calculation for calculating driving force output by the vehicle based on the detected operating state Means, a gradient estimating means for estimating a gradient of a traveling road on which the vehicle is traveling based on the calculated traveling resistance and driving force, a speed ratio setting means for setting a speed ratio based on the estimated gradient, And a speed ratio determining means for determining a speed ratio of the vehicle automatic transmission based on the set speed ratio, and wherein the gradient estimating means detects a vehicle speed from the detected driving state. Calculated acceleration, and as it configured to change the time constant of data processing necessary for the estimation based on the vehicle acceleration calculated.

As a result, the responsiveness and the estimation accuracy of the gradient estimation can be made compatible with each other, so that the gear ratio can be controlled optimally and the drivability can be improved. More specifically, two types of gradient estimation information, emphasizing accuracy and real-time performance, can be selectively used according to road surface conditions and driving conditions, as necessary, and an optimal shift that matches the application can be performed. Drivability can be improved.

According to a second aspect of the present invention, when the brake operation is performed, the gradient estimating means estimates a braking force from a gradient estimated value before the brake operation and a gradient estimated value during the brake operation. It is configured to maintain the estimated gradient based on the applied braking force. by this,
In addition to the effects described above, the accuracy can be further improved.

According to a third aspect of the present invention, the gradient estimating means estimates a corner resistance from the turning force of the vehicle, and corrects the estimated gradient based on the estimated value. Thereby, in addition to the above-described effects, the responsiveness can be further improved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic diagram showing an overall control apparatus for an automatic transmission for a vehicle according to the present invention. In the case of the illustrated embodiment, a belt-type continuously variable transmission (CVT) is provided as the automatic transmission.

In FIG. 1, reference numeral 10 denotes an internal combustion engine or its main body (hereinafter referred to as "engine" or "engine main body").
). The engine 10 includes an intake pipe 12 and a throttle valve 14 arranged on the way. The throttle valve 14 is mechanically disconnected from an accelerator pedal 16 disposed on the floor of a vehicle driver's seat (not shown), is connected to a pulse motor 18, and is driven by its output.

An output shaft (crankshaft) 20 of the engine (body) 10 is connected to a belt-type continuously variable transmission 24 (CVT; hereinafter referred to as "transmission").

More specifically, an output shaft 20 of the engine (body) 10 is connected to an input shaft 28 of the transmission 24 via a dual mass flywheel 26.
Engine (body) 10 and transmission 24
Is mounted on a vehicle indicated by reference numeral 29 only.

The transmission 24 includes a metal V-belt mechanism 3 disposed between an input shaft 28 and a counter shaft 30.
2, a planetary gear type forward / reverse switching mechanism 36 disposed between the input shaft 28 and the drive-side movable pulley 34, and a starting clutch 42 disposed between the counter shaft 30 and the differential mechanism 40. Be composed. The power transmitted to the differential mechanism 40 is transmitted to left and right drive wheels (not shown) via a drive shaft (not shown).

The metal V-belt mechanism 32 includes a drive-side movable pulley 34 disposed on the input shaft 28 and a counter shaft 3
The pulley comprises a driven movable pulley 46 disposed above the pulley and a metal V-belt 48 wound between the two pulleys. The drive-side movable pulley 34 includes a fixed pulley half 50 disposed on the input shaft 28, and a movable pulley half 52 movable relative to the fixed pulley half 50 in the axial direction.

On the side of the movable pulley half 52, a drive side cylinder chamber 54 is formed surrounded by a cylinder wall 50a connected to the fixed pulley half, and an oil passage 54a is formed in the drive side cylinder chamber 54. A side pressure for moving the movable pulley half 52 in the axial direction is generated by the hydraulic pressure supplied through the pulley.

The driven-side movable pulley 46 is composed of a fixed pulley half 56 disposed on the counter shaft 30 and a movable pulley half 58 that can move axially relative to the fixed pulley half 56. On the side of the movable pulley half 58, a driven cylinder chamber 60 is formed surrounded by a cylinder wall 56a connected to the fixed pulley half 56, and is supplied into the driven cylinder chamber 60 via an oil passage 60a. The hydraulic pressure generates a side pressure that moves the movable pulley half 58 in the axial direction.

A regulator valve group 64 for determining a pulley control oil pressure supplied to the drive-side cylinder chamber 54 and the driven-side cylinder chamber 60;
Shift control valve group 6 for supplying pulley control oil pressure to 60
6 are set, an appropriate pulley side pressure is set so that the V-belt 48 does not slip, the pulley width of both pulleys 34 and 46 is changed, and the winding radius of the V-belt 48 is changed. Thus, the gear ratio is changed steplessly.

The planetary gear type forward / reverse switching mechanism 36 includes a sun gear 68 connected to the input shaft, a carrier 70 connected to the fixed pulley half 50, a ring gear 74 fixedly held by a reverse brake 72, and a sun gear. And a forward clutch 76 capable of connecting the carrier 68 and the carrier 70.

When the forward clutch 76 is engaged, all gears rotate integrally with the input shaft 28, and the drive pulley 34
Are driven in the same direction as the input shaft 28 (forward direction). When the reverse brake 72 is engaged, the ring gear 74 is fixed and held, so that the carrier 70 is driven in the direction opposite to the sun gear 68, and the drive pulley 34 is driven in the direction opposite to the input shaft 28 (reverse direction). Is done. When both the forward clutch 76 and the reverse brake 72 are released, the power transmission via the forward / reverse switching mechanism 36 is cut off, and the power transmission between the engine 10 and the drive-side drive pulley 34 is performed. I will not be.

The starting clutch 42 is a clutch that controls on (engagement) and off (release) power transmission between the counter shaft 30 and the differential mechanism 40. The output of the engine is divided and transmitted to left and right wheels (not shown) by a differential mechanism 40 via gears 78, 80, 82, and 84. When the starting clutch 42 is off (disengaged), the transmission is in a neutral state.

The operation of the starting clutch 42 is controlled by a clutch control valve 88, and the reverse brake 72 and the forward clutch 76
Is controlled by a manual shift valve 90 in response to operation of a manual shift lever (not shown).

The control of these valve groups is performed based on a control signal from a transmission control unit 100 composed of a microcomputer.

Here, the crank angle sensor 102 is located at an appropriate position near the camshaft (not shown) of the engine body 10.
And outputs a signal proportional to the crank angle (the engine speed Ne is calculated by counting the crank angle). Further, an absolute pressure sensor 104 is provided at an appropriate position downstream of the throttle valve 14 in the intake pipe 12, and outputs a signal P proportional to the absolute pressure (engine load) PBA in the intake pipe.

A water temperature sensor 106 is provided at an appropriate position of a cylinder block (not shown), and outputs a signal proportional to the engine cooling water temperature TW. Further, an intake air temperature sensor 107 is provided at an appropriate position of the intake pipe 12, and outputs a signal proportional to the intake air temperature (corresponding to substantially the outside air temperature).

A throttle opening sensor 108 is provided near the throttle valve 14 and outputs a signal proportional to the throttle opening θTH. An accelerator opening sensor 110 is provided near the accelerator pedal 16. A signal proportional to the accelerator opening ACC depressed by the driver is output.

A brake switch 112 is provided near a brake pedal or a brake mechanism (not shown), and outputs a brake ON signal in response to a driver's brake operation.

In the transmission 24, a rotation speed sensor 114 is provided near the input shaft 28, and outputs a signal proportional to the rotation speed NDR of the input shaft 28.
In the vicinity of the driven-side movable pulley 46, a rotation speed sensor 11 is provided.
6 is provided, and outputs a signal proportional to the rotation speed of the driven-side movable pulley 46, that is, the rotation speed NDN of the input shaft (counter shaft 30) of the starting clutch 42. Also, the gear 78
, A rotation speed sensor 118 is provided, and the rotation speed of the gear 78, that is, the rotation speed NO of the output shaft of the starting clutch 42
Outputs a signal proportional to UT.

Further, a vehicle speed sensor 1 is provided near a drive shaft (not shown) connected to the differential mechanism 40.
22 for outputting a signal proportional to the vehicle speed V. A shift lever position switch 124 is provided near a shift lever (not shown) on the floor of the driver's seat, and a range position (D, N, P,...) Selected by the driver is provided.
Output a signal proportional to

An acceleration sensor 126 is provided near the center of the vehicle 29, and outputs a signal proportional to a lateral acceleration G acting in a direction orthogonal to the traveling direction of the vehicle 29. A steering angle sensor 12 is provided near a steering wheel (not shown) disposed in a vehicle driver's seat (not shown).
8 for outputting a signal according to the steering angle.

As described above, this device includes the transmission control unit 100, and also includes the engine control unit 200 also formed of a microcomputer. The outputs of the crank angle sensor 102, the absolute pressure sensor 104, the water temperature sensor 106, and the throttle opening sensor 108 in the above-described sensor group are input to the control units 100 and 200.

This device also includes an integrated control unit 300 similarly composed of a microcomputer, and includes an accelerator opening sensor 110, a vehicle speed sensor 1
Outputs such as 22 are input to the integrated control unit 300.

The integrated control unit 300 determines the target gear ratio, that is, the target value of the input rotational speed NDR, and sends it to the transmission control unit 100.

The transmission control unit 100 drives the movable pulleys 34 and 46 so as to reach the target NDR,
Control the gear ratio. Here, the target NDR is the target rotation speed of the drive-side movable pulley 34 of the transmission 24. By defining the target NDR with respect to the vehicle speed V, the gear ratio (hereinafter referred to as “ratio” or “ratio”) is univocally determined. Determined and controlled.

As described above, in this embodiment, since the transmission 24 is provided and the ratio can be controlled steplessly, the drivability can be controlled by optimally controlling the ratio in accordance with the operation state as described later. Can be improved.

Further, the integrated controller 300 determines the target throttle opening and sends it to the throttle controller 400. The throttle control unit 400 drives the throttle valve 14 via the pulse motor 18 so as to have the determined value.

Next, the operation of the control device for a vehicle automatic transmission according to the present invention will be described.

FIG. 2 is a flow chart showing the operation. Before starting the description of the figure, the operation of the control device for a vehicle automatic transmission according to the present invention will be outlined with reference to FIG.

As described above, this apparatus focuses on the fact that the superiority of the drivability appears remarkably when going up and down a hill, and based on the analysis of the driving results mainly on mountainous roads, the factors affecting the drivability are determined by physical quantities (driving force). ), And the relationship between drivability and physical quantities found there was obtained as an evaluation index, and the ratio (or driving force) was controlled based on that.

Specifically, a physical quantity state estimation model as shown in FIG. 3 was created, and the correlation with the drivability was analyzed. More specifically, in the manipulated variable input unit, the degree of driver demand is estimated based on the accelerator opening operated by the driver and is indexed. FIG. 4 shows the model.

One of the features of the model shown in FIG. 4 is that the accelerator opening and the amount of depression of the brake are grasped in the same dimension, and the return of the accelerator is regarded as a brake operation and is modeled. That is, as shown in FIG. 5, the driving force (torque) was captured as a negative value based on the estimated brake (described later). Also, as shown in FIG. 6, the gain is adjusted based on the time for stepping on the accelerator pedal and the brake pedal.
These will be described later.

In the own vehicle section of the model shown in FIG. 3, the own vehicle gain is estimated. That is, as shown in FIG. 7, a model showing the difference between the ideal vehicle response and the actual vehicle response is created, and based on the model, the actual output and the driver request output are combined, and more specifically, the difference is calculated. Then, the responsiveness (driving force) of the own vehicle is estimated. This will also be described later.

Next, the indices obtained from the model shown in FIG. 4 and the model shown in FIG. 7 are averaged and compared with a predetermined value to determine whether the driver intends the sport running characteristic or the relaxed running characteristic. Determine if Here, the sports driving characteristics are characteristics of a high response when the driving force change with respect to the accelerator opening is high, and the relaxing driving characteristics are low response characteristics when the driving force change with the accelerator opening is compared with the sports driving characteristic, in other words. It means the characteristic that the degree of driver intervention can be reduced. The sports running characteristics correspond to the first running characteristics described above, and the relaxed running characteristics correspond to the second running characteristics described above.

When it is determined that the driver intends to have the relaxed driving characteristic, the driving condition is determined based on the gradient estimated from the vehicle speed, that is, whether the vehicle is traveling uphill, downhill or on flat ground. Judgment, the ratio is controlled so that the driving force becomes a desired value, and when it is determined that the driver intends the sport running characteristics, the driving force also becomes the desired value, and the relaxed driving is performed. The ratio is controlled so that the driving force response is higher than the characteristic.

Specifically, a ratio control output index is calculated to obtain a ratio ratio (ratio multiplied value), and the ratio is determined by multiplying the base ratio map value.

A description will be given with reference to the flow chart of FIG. The illustrated program is, more specifically, an operation performed in the integrated control unit 300, and is executed at predetermined time intervals, for example, at 0.1 second intervals.

First, in S10, the gradient θ,
That is, the gradient θ of the traveling road on which the own vehicle is traveling is estimated (calculated). FIG. 8 is a subroutine flowchart of the process in S10.

In this control, as described above, the gradient of the traveling road is calculated (estimated) in order to determine the traveling condition. When the gradient is estimated over a long period of time (hereinafter referred to as "long The estimated value obtained is referred to as “span gradient estimation”, and the estimated value obtained is referred to as “long span estimation gradient”. The estimated value obtained is referred to as “short span estimation gradient”).

More specifically, gradient estimation is performed by using two types of predetermined detection conditions, techniques, detection timings, and filtering for gradient value estimation, in other words, changing the time constant of the filter. did. Then, according to the driving state of the vehicle, one of the estimated gradients is selected to determine the traveling environment, and the ratio control is performed.

Referring to FIG. 8, S100 to S110
The processing of (a) shows the above-described short span estimation gradient calculation processing. In S100, the detected vehicle speed V and acceleration d
v (vehicle acceleration; first-order difference value or differential value of detected vehicle speed), throttle opening degree θth, ratio (NDR) rat
io and the steering angle (lateral acceleration G) are read.

FIG. 9 is an explanatory diagram showing the processing of S100, which is performed using a low-pass filter 500 as shown. That is, when reading the detected value, the low-pass filter 50 is used.
Filter processing is performed via 0.

More specifically, when estimating the short-span gradient, the cutoff frequency of the low-pass filter 500 is set high, and the response is increased by setting the attenuation characteristic low. On the other hand, when estimating the long-span gradient, the cutoff frequency is set low and the damping characteristic is set high.In other words, high accuracy is achieved by removing high frequency components that have many disturbance components due to the effects of acceleration and deceleration. I tried to raise it.

In S100, since the short-span gradient is estimated, the filter output value in which the cutoff frequency is set high and the attenuation characteristic is set low is read.

Then, the program proceeds to S102, in which a torque Te output from the engine (main body) 10 is calculated (estimated) using a throttle opening-torque conversion table (not shown) appropriately set from the detected throttle opening θth. I do.

Then, the program proceeds to S104, in which the driving force F outputted by the vehicle 29 is calculated (estimated). Specifically, it is calculated using the following equation. F = (1 / r) × [(Te−Tf) × ratio × k−dNe / dt · C [kgf]. . . Equation 1 Here, r: tire radius, Tf: total value of transmission friction torque, k: final reduction ratio, and C: inertial mass component.

Next, the routine proceeds to S106, where the corner resistance Rc
Is calculated. Here, the corner resistance means a deceleration force generated by deformation of the tire at the time of cornering (that is, turning force). FIG. 10 is a block diagram illustrating the process.

In the following, a lateral G map characteristic (characteristic not shown) is searched from the value obtained by converting the steering steering angle input value into an absolute value and the detected vehicle speed, and a lateral acceleration G (acceleration acting on the vehicle in a lateral direction) is obtained. Ask for. Next, map characteristics (characteristics not shown) that are appropriately set from the calculated lateral G and the detected vehicle speed
To find the corner resistance Rc.

The calculation (estimation) accuracy of the running resistance R can be improved by adding the obtained corner resistance Rc at the time of calculating the running resistance R described later. Note that the corner resistance hold value is obtained and used in mountain / city area determination described later.

Returning to the description of FIG. 8, the program proceeds to S108, where the running resistance R is calculated (estimated). Specifically, using the corner resistance Rc and the detection parameter values (vehicle speed V, acceleration dv) obtained as described above and values (vehicle weight, air resistance coefficient, rolling resistance coefficient) previously obtained and stored, and the like, Is calculated as follows.

R = ρCdAV ² + ma + msinθ + μmcosθ + Rc [kgf]. . . Equation 2 where ρ: air density coefficient, Cd: air resistance coefficient, A:
Projection area of the entire vehicle, θ: slope, μ: rolling resistance coefficient,
m: vehicle weight, a: acceleration, Rc: corner resistance.

Next, the routine proceeds to S110, where the above equations 1, 2
Is calculated from the following equation. sin θ = [F− {ρCdAV ² −ma + μm cos θ + Rc}] / m [°]. . . The value obtained by Expression 3 is defined as the short span estimation gradient θ short. In addition, 0.1 sec for the on-board microcomputer
Since it is difficult to solve during the control cycle of c and there is no need to solve it, sin θ is actually treated as it is as the gradient θ. Incidentally, as far as the inventors have confirmed, the estimated short span gradient value thus obtained has an accuracy of ± 5 ° or less.

Subsequently, the program proceeds to S112, in which it is determined whether or not the ON signal of the brake switch 112 has been output. That is, it is determined whether or not the driver is operating a brake mechanism (not shown).

When the result in S112 is affirmative, the program proceeds to S114, in which it is determined whether the brake operation was performed during the previous control cycle (previous program loop). The previous value of ol
d Hold the θ short as the pre-brake gradient value θbeforebrk.

On the other hand, if the result in S114 is affirmative, S11
8, the product of the estimated short-span gradient value and the vehicle weight m is set as the gradient-equivalent resistance Rb at the time of braking (during the braking operation), and the process proceeds to S120 to calculate (estimate) the braking force Fbrk from the equation in the figure. I do.

That is, assuming that the road surface gradient is constant before and after the brake switch 112 is turned on, the braking force is calculated as the deviation between the driving force corresponding to the gradient immediately before the brake switch 112 is turned on and the driving force corresponding to the gradient during braking. You can ask.

In the process of S120, the pre-brake gradient estimated value θbeforebrk is held since it was previously determined that the brake was also applied, and the pre-brake gradient equivalent resistance msin θbeforebrk is obtained from the value.
Resistance msi equivalent to the gradient at the time of braking determined in S118
The braking force Fbrk is calculated from the difference from the nθ short circuit.

Then, the program proceeds to S122, in which (S
116) The previous value ol of the value θ short and the estimated gradient value
It is determined whether the difference Δθ short from dθ is equal to or less than a predetermined value α. That is, when the vehicle spins or slips, the estimated gradient θ short becomes an abnormally high value on the negative side, so the threshold α is appropriately set, and in S122, the short span estimated gradient value θ short and the previous value of the estimated gradient value are compared. When it is determined that the difference Δθ short from the value old θ is equal to or greater than the threshold value α, it is determined that spin or slip has occurred.

When the result in S122 is affirmative, it can be determined that the vehicle is traveling on a normal road, and the program proceeds to S124, in which the pre-brake gradient estimated value θbeforebrk is set as the gradient estimated value θ.

On the other hand, when the result in S122 is negative, it is considered that the vehicle is traveling on a rough road with a small gripping force and a slip state has occurred, so the flow proceeds to S126 to perform a low μ road control process. This will be described later.

Next, the process proceeds to S124, in which the held pre-brake estimated gradient value θbeforebrk is set to the estimated gradient value θ, and the process proceeds to S128 to set the dv value 20 times before to 20old dv.
Proceeding to S130, the estimated gradient value θ is set to old θ, and the program ends.

On the other hand, when the result in S112 is NO, that is,
When it is determined that the brake is not currently operated, the process proceeds to S132, and it is determined whether a time of 0.5 sec or more has elapsed since the brake switch was turned off.

When the result in S132 is affirmative, the program proceeds to S134, where it is determined whether or not the difference between the current acceleration dv and the acceleration 20old dv 2 seconds before is 1.0 [m / sec ² ] or less, as shown in the figure.

When the result in S134 is affirmative, it can be determined that the vehicle is in steady running with little change in speed.
Calculate the long. That is, the long span estimation gradient is calculated only when the vehicle is traveling stably with a change in acceleration smaller than a predetermined value.

S136 to S146 show the long span estimation gradient calculating process. In S136, the detected vehicle speed V, acceleration dv, throttle opening θth, ratio rat
io and the steering angle (lateral acceleration G) are read.

Here, as described with reference to FIG. 9, the cut-off frequency of the filter 500 is set low and the attenuation characteristic is set high to read the filtered sensor output value. Note that the processing from S138 to S144 is the same as the calculation processing of the estimated short span gradient, and thus the description is omitted. The estimated gradient value obtained in S146 is set to θ long. This value has an accuracy of ± 2 ° or less as far as the inventors have confirmed.

It should be noted that the short span estimation gradient and the long span estimation gradient are selectively used as described later depending on the application.

Subsequently, the flow proceeds to S148, in which the vehicle weight is calculated (estimated) by an appropriate method. The vehicle weight is obtained and stored in advance, but is corrected when it is determined that the vehicle is running stably to increase the accuracy.

Then, the process proceeds to S150, where the long span estimated gradient value θ long obtained in S146 is used as the estimated gradient value θ.
Proceed to S128 and below.

When the result in S132 is negative, that is, when it is determined that the predetermined period 0.5 seconds has not elapsed since the brake switch was turned off, or when the result in S134 is negative, the process proceeds to S152, where the long span estimated gradient is determined. The previous value old θ long of the value is set as the long span estimation gradient value θ long.

Then, the process proceeds to S154, in which it is determined whether or not the difference Δθ short between the estimated short span value θ short calculated in S110 and the previous value old θ of the estimated gradient value is equal to or smaller than a predetermined value β. That is, similarly to the processing of S122, the threshold value β is set, and it is determined that the difference Δθ short between the short span estimated gradient value θ short and the previous value old θ of the estimated gradient value is equal to or larger than the threshold value β. At this time, it is determined that spin or slip has occurred.

When the result in S154 is affirmative, it is determined that the vehicle is traveling normally, and the routine proceeds to S156, where the pre-brake gradient estimated value θ short is set as the gradient estimated value θ. On the other hand, S1
If the result in 54 is negative, it is considered that the vehicle is traveling on a rough road, so the flow proceeds to S126 to perform a low μ road control process.

Returning to the flow chart of FIG.
Proceeding to 11, the mountain and city area judgment is performed. This will be described later.

Then, the program proceeds to S12, in which the braking force fbrk is
Is estimated.

When the driving force F immediately before braking and the driving force F during braking are calculated, they are as follows. Incidentally, various values such as the driving force F immediately before the braking are added with 0, and those during the braking are added with 1.

The driving force immediately before braking is calculated from the following equation. ^{F0 = ρCdAV0 2 + ma0 + msinθ0} + μmcosθ0 + fbrk0 + Rc0 [kgf]

The driving force during braking is calculated from the following equation. F1 = ρCdAV1 ² + ma1 + msinθ1 + μmcosθ1 + fbrk (1) + Rc1 [kgf]

From the assumption, the following is derived. msinθ0 = msinθ1 Rc0 = Rc1 = 0 μmcosθ0 = μmcosθ1

Therefore, the braking force fbrk is obtained as follows. fbrk = fbrk1-fbrk0 = F1- F0-ρCdAV1 2 -ρCdAV0 2 - m (a1-a0) -Rc1-Rc0. . . Equation 3

Next, the process proceeds to S14, where the above-described driver request estimation is performed. The driver's request is indicated by a throttle opening and a throttle opening change amount.

Referring to FIG. 4, the reverse torque map is retrieved from the estimated braking force fbrk, converted into a negative throttle opening, and subtracted from the detected throttle opening. That is, as shown in FIG. 5, the estimated braking force is converted into a driving force around the axle, and a map having a characteristic opposite to that of the map previously used for calculating the torque Te is searched to calculate a throttle opening value. Negative value.

That is, in this control, as shown in the upper part of FIG. 4, the accelerator opening and the amount of depression of the brake are grasped in the same dimension, and the movement in the return direction beyond the full throttle of the accelerator is regarded as a brake operation and modeled. .

Next, the obtained difference is multiplied by a P (proportional) gain, and the obtained value is peak-held and attenuated with time, and the obtained value is defined as a driver request (determined by the throttle opening (θth)). Similarly, the obtained difference (not shown) is multiplied by a D (differential) gain, and a value obtained by peak-holding and attenuating the obtained value with time is obtained as a driver request degree (throttle opening degree change amount dth). More specifically, it indicates the amount of change in the throttle opening).

Since the D gain is used because the accelerator stepping speed or the step change time indicates the magnitude of the driver's demand, the differential value of the accelerator opening is weighted as a method on a model that reflects this. That's why. In addition, as shown in FIG. 6, the D gain is changed by obtaining the time for changing over from the throttle to the brake.

At the same time, the aforementioned vehicle driving force (corresponding to the aforementioned vehicle gain) is estimated.

Referring to FIG. 7, the upper part of the figure is a model describing the ideal response of the own vehicle (first model).
And the lower part shows a model (second model) that describes the actual response of the own vehicle. Then, the driving force is obtained by the same calculation as in FIG. 4 using the model 1, and the product obtained by multiplying the detected vehicle speed is regarded as the driver's required output.

The estimated driving force is calculated based on the engine torque Te using the second model, and the product obtained by multiplying the value obtained by subtracting the estimated braking force by the detected vehicle speed is calculated by the vehicle. Is regarded as the actual output output to Then, the actual output is subtracted from the required output in the addition / subtraction stage to obtain a difference, which is set as a deviation output (or a difference output). This deviation output indicates how much the driver's demand deviates from the actual output.

In the flow chart of FIG.
The process proceeds to step S16, and the obtained value is used as an index from 1 to 5 points. The process proceeds to step S18 to combine, more specifically, average. FIG. 11 is an explanatory diagram showing the processing. Specifically, it is indexed (dimensionless) with a non-dimensional numerical value from 1 to 5 points using an appropriate function (represented by a linear function in the figure), and the calculated value is searched for a corresponding evaluation index.

Thus, the driver's request (whether the vehicle is intended for relaxed driving or sports driving) is added to the index based on the engine performance of the own vehicle.
It is possible to create an evaluation index reflecting the above. Although the average is used as the combining method, a maximum value or a minimum value may be selected. Furthermore, the average is not limited to a simple average, and a load average or the like may be used.

Here, the reason why the index of the driver demand estimated value and the index of the own vehicle driving force estimated value are synthesized is that, for example, when the vehicle is running steadily on a highway, the throttle opening degree and its change amount are small, but the driving force is small. Is big. That is, the vehicle is running with high sports properties. Therefore, in order to determine whether or not the driver wants to run sports, it is understood that the throttle opening and the change amount thereof are insufficient, and that the estimated value of the own vehicle driving force is necessary.

Subsequently, the flow advances to S20, where it is determined whether or not the obtained index exceeds a predetermined value k. That is, it is determined based on the obtained index whether the driver intends to relax or run in sports, and appropriate control is performed according to the determination.

If the result in S20 is affirmative, the control mode is determined to be the relax control mode, and the program proceeds to S22, in which the running condition is determined using the estimated gradient θ of the running road. Specifically, this is performed by comparing the gradient θ with the aforementioned predetermined values α and β.

If it is determined in step S22 that the gradient θ is equal to or greater than the predetermined value α, it is determined that the vehicle is climbing a slope, and the flow advances to step S24 to set a ratio based on the instantaneous marginal driving force.

Referring to FIG. 12, the instant margin driving force is a term coined by the inventors, and the accelerator is fully opened (or a predetermined opening degree) with the current ratio and engine speed. It is the difference between the full-open output that is output at the time and the actual engine torque that the engine is actually outputting at the current ratio and the engine speed, and the state of the driving force change with respect to the vehicle margin or the accelerator opening ( (A so-called good accelerator). Therefore, it is a concept different from the generally defined margin driving force (difference between the full-open output and the running resistance).

FIG. 13 shows the control when it is determined that the driver intends to relax and the vehicle is in an uphill situation. As shown in the figure, the ratio is set using the model shown in the upper part of the figure so that the instantaneous excess driving force becomes the target instantaneous excess driving force in the lower part of the figure.

According to the experiments conducted by the inventors, the target instantaneous margin driving force is such that the maximum acceleration is about 0.1 G and the vehicle weight is 1 t.
In this case, about 50 to 100 kgf was suitable for relaxing uphill driving.

More specifically, the target instantaneous margin driving force is shown in FIG.
As shown in FIG. 15 and a three-dimensional map representing the driving state, the driving state estimation index is set variably, and the driving state estimation index increases, in other words, decreases so that the driver does not want the driving force. And the vehicle speed V is variably set. That is, since a larger acceleration / deceleration performance is required at a low vehicle speed than at a high vehicle speed, the target instantaneous margin driving force is set to increase. By setting in this way, it is possible to reduce noise generated when the engine speed increases at a high vehicle speed, and it is possible to reduce the discomfort.

Then, the program proceeds to S26, in which the set ratio is indexed to a numerical value from 1 to 5 points by an appropriate method.

On the other hand, when it is determined in S20 that the estimated gradient θ is equal to or smaller than the predetermined value α, it is determined that the traveling condition is downhill, and the process proceeds to S28.

FIG. 16 is an explanatory block diagram showing the control. Using the model shown in the upper part of FIG. 16, the ratio is set so that the driving force matches the running resistance or the target driving force becomes zero. . That is, as shown in FIG. 17, when the vehicle is descending a hill, the engine brake driving force fe acts on the vehicle in the deceleration direction and the running resistance R acts on the vehicle in the acceleration direction, but the vehicle travels with the engine braking force (shown by -fe) when the throttle is fully closed. The ratio is determined so that the resistances R match. Next, the process proceeds to S30, where the determined ratio is indexed.

If it is determined in step S22 that the estimated gradient θ is larger than the predetermined value β and equal to or smaller than α, it is determined that the traveling state is on a flat ground, and the flow advances to step S32.

To explain the flatland control, the superiority of drivability on a flat ground is not as remarkable as on an uphill or downhill, and in this embodiment, the DBW ( Pulse motor 1
8 and the throttle control unit 400) to control the driving force by controlling the throttle opening. More specifically, the instantaneous margin driving force is controlled by a ratio, and the driver's required driving force is controlled by a throttle opening.

FIG. 18 is a subroutine flowchart showing the control. The program shown in FIG.
It is executed every one second.

When the control shown in FIG. 18 is summarized, the driver's required driving force is compared with the actual driving force, and the throttle opening is opened and closed by a predetermined amount according to the comparison result. Next, the total efficiency ηtotal of the engine and the transmission is calculated and compared with the previous value. For example, if the efficiency is increased and the previous time was the subtraction control of the target instantaneous margin driving force, the efficiency is further increased by the decreasing direction control. Judge and further subtract. As a result, the ratio follows the high geared direction. On the other hand, when the efficiency is reduced by the subtraction control, the control is switched to the addition control. As described above, the change in the total efficiency and the control direction of the target instantaneous margin driving force are determined, and the control is performed so that high total efficiency is obtained.

The following description is based on the above assumption.
0, it is determined whether or not the flatland fuel efficiency control is currently being executed,
If affirmed, the process proceeds to S182, where it is determined whether the actual driving force is greater than the driver's requested driving force.
Proceeding to 184, the current throttle opening th is
a is added, and the throttle valve 14 is controlled in the opening direction so as to have the added value.

If the result in S182 is NO, S18 is reached.
6 to the predetermined value tha from the current throttle opening th.
Is subtracted, and the throttle valve 14 is controlled in the closing direction so as to have the subtracted value. When the result in S180 is NO, the processing from S182 to S186 is skipped.

Next, proceeding to S188, the target instantaneous margin driving force (referred to as "Fie-obj") is decreased toward a predetermined amount of zero, and then proceeding to S190, first, the efficiency ηeng and ηtm of the engine 10 and the transmission 24 are calculated.

Specifically, the engine efficiency ηeng and the transmission ηtm are calculated by a map search. More specifically, the engine efficiency ηeng is equal to the engine torque Te.
(Calculated in S102) and a map which is appropriately set in advance so that the fuel consumption rate is the best with the engine speed Ne is searched for and determined, and the transmission ηtm is similarly determined to be the best in the NDR and NDN. Thus, a map which is appropriately set in advance is searched for and obtained.

Then, the obtained engine efficiency ηeng is multiplied by the transmission ηtm to obtain a total efficiency ηto
tal, and calculates the calculated value (current value) as the previous value
Replace with the previous value and update the previous value. In the first program loop, an appropriate value (for example, 0) is set as the previous value. The total efficiency ηtotal indicates the efficiency of the engine and the transmission at the fuel consumption rate.

Next, the program proceeds to S192, in which the current instantaneous driving force (referred to as "Fie") is read and similarly updated with the previous value.

Next, the routine proceeds to S194, where the present value (calculated value)
Is greater than or equal to the previous value, and if affirmative, S1
The program proceeds to 95, where it is determined whether the target instantaneous marginal driving force sequential addition control (S196) was performed last time. When affirmative in S195, the process proceeds to S196, in which the predetermined value x is added to the target instantaneous margin driving force, and when negative, S197 is performed.
Then, the predetermined value x is subtracted from the target instantaneous margin driving force.

When the result in S194 is NO, S19 is reached.
8, similarly, it is determined whether or not the target instantaneous margin driving force sequential addition control was performed last time, and if affirmative, S19 is performed.
7 and, if not, the flow proceeds to S196.

As described above, considering the previous processing, S19
6, by performing the processing of S197, it is possible to control to a position where η total becomes large. That is, as shown in FIG. 19, by increasing or decreasing the target instantaneous margin driving force, the target instantaneous margin driving force value Fηmax at which the total efficiency is the best in the fuel consumption rate can be searched and trapped at that point.

Here, subtracting the predetermined value x from the target instantaneous margin driving force value means adding the predetermined value x to the target instantaneous margin driving force value on the high ratio side by an amount corresponding to the transmission ratio corresponding to the predetermined value x. This means that the driving force is controlled by controlling the transmission ratio to the low ratio side by an amount corresponding to the predetermined value x.

That is, driving the target instantaneous margin driving force value in the zero direction means driving the throttle opening in the full opening direction regardless of the accelerator opening. The engine efficiency at which the fuel consumption rate is the best is usually located near the throttle fully open, and if the transmission efficiency of the transmission is almost constant, the best point should be obtained by changing the target instantaneous margin driving force value toward zero. Can be. Therefore, FIG.
By trapping the best point Fηmax as shown in
The fuel consumption rate can be optimized.

Returning to the description of FIG. 2, if the result in S20 is NO, it is determined that the driver wants to run sports, and
Proceeding to 34, a ratio is set using the instantaneous margin driving force or driving force, and proceeding to S36 for indexing. It should be noted that the characteristic of this control is mainly in the relaxed traveling, and a detailed description thereof will be omitted.

Then, the flow advances to S38 to convert the obtained index into a ratio control output index, and the flow advances to S40 to apply the ratio to the vertical axis of the illustrated characteristic to calculate the ratio of the horizontal axis (multiplied ratio). Next, in S42, the ratio is determined by multiplying the obtained ratio by the base ratio map value (searched from the throttle opening and the vehicle speed).

Now, returning to the description of the flowchart of FIG. 8, the processing of S126 will be described.

This processing is based on the above-mentioned traveling condition (uphill / downhill).
Unlike the determination, the slip level of the traveling road is determined, and the ratio control is performed accordingly. Specifically, the state of the traveling road is determined into a plurality of states, and ratio control is performed based on the result.

FIG. 20 is a subroutine flowchart for explaining the processing of S126, and FIG. 21 is a graph showing changes in the driving force corresponding to the gradient with respect to the state of the traveling road.

Referring to the flow chart of FIG.
At 200, peak hold and time subtraction of the obtained estimated gradient equivalent driving force are performed. More specifically, the obtained estimated gradient-equivalent driving force is held and subtracted by a predetermined amount each time the program loop shown in the drawing is performed, and when a larger value is obtained, it is replaced.

The process of S200 will be described with reference to FIG. 21. When the vehicle spins or slips, the value of sin θ obtained by the above-described process, that is, the value of the estimated gradient equivalent driving force (msin θ) is negative. Is calculated with a peak. In this process, the value of the driving force corresponding to the estimated gradient at the peak is held and a value obtained by subtracting time ((msinθ))
hd), and using this, the state of the traveling road is determined.

Then, the program proceeds to S202, in which it is determined whether or not the absolute value of the difference between the time-subtracted value and the driving force corresponding to the gradient exceeds a predetermined value B. That is, the attenuation curve (shown by a in FIG. 21) obtained by subtracting the estimated gradient-equivalent driving force at the peak time is less than the value obtained by subtracting the predetermined value B from the estimated gradient-equivalent driving force (shown by b in FIG. 21). It is determined whether or not. When the result in S202 is affirmative, it is determined that the vehicle is traveling on a low μ road with a small gripping force (coefficient of friction), and the process proceeds to S204, where the driving force corresponding to the estimated gradient corresponding to the peak is attenuated again with the time. The absolute value of the difference from the equivalent driving force (msinθ) is determined, and it is determined whether the difference is equal to or greater than a predetermined value C. That is, an attenuation curve obtained by subtracting the estimated gradient-equivalent driving force at the peak time with respect to time (indicated by a in FIG. 21).
Is smaller than the value obtained by subtracting the predetermined value C from the estimated gradient equivalent driving force (indicated by c in FIG. 21).

Then, the program proceeds to S206, in which the intake air temperature sensor 10
7 is read as being considered to be equivalent to the outside temperature,
Proceeding to 8, it is determined whether the intake air temperature (outside air temperature) is less than a specified value. The specified value is set to an appropriate value that can determine whether or not the road surface is frozen. If affirmative in S208, S2
The program proceeds to S10, where it is determined that the vehicle is on a frozen road, and instantaneous margin driving force control is performed at the time of determination of a frozen road. Is determined to be a rough road, and instantaneous margin driving force control is performed when the rough road is determined.

The process such as S212 will be described. A target instantaneous driving force is searched for and obtained using the current vehicle speed V from the characteristics set in advance. FIG. 23 is a graph showing the characteristics.

As shown in FIG. 23, the target instantaneous margin driving force characteristics were set separately for the determination of the frozen road and the determination of the bad road. That is, at the time of judging an icy road, the instantaneous margin driving force control is performed such that the target value is set lower than the normal time, and at the time of judging a bad road, the instantaneous margin driving force control of the target value set higher than the icy road is performed. I made it.

More specifically, as shown in FIG. 13, the difference is obtained by subtracting the target instantaneous margin driving force from the instant margin driving force.
A value obtained by multiplying the value by a coefficient k is input to a preset conversion table as shown in the figure as an input u, and an output x indicating an index is obtained. Next, the obtained output x is input to a previously set conversion table as shown in FIG.
Ask for.

As described above, the driving force control is performed by using the instantaneous margin driving force representing the degree of goodness with respect to the change in the accelerator opening as the target value, and the target value is set to a value lower than the normal setting of the instantaneous margin driving force. As a result, the generation of abrupt driving force on frozen roads and rough roads is suppressed, and the occurrence of spins and the like is prevented.

On the other hand, if the result in S202 is NO, S21.
Proceeding to 4, it is determined whether or not the absolute value of the gradient equivalent resistance (msinθ) is less than a predetermined value A. When a negative determination is made in S214, similarly, it is determined that the vehicle is traveling on a low μ road with a small gripping force, and the process proceeds to S204 and thereafter to perform the low μ road control, and when affirmative, the process proceeds to S216. And the control is performed based on the driving force at the time of the normal determination.

Specifically, the target driving force is determined in accordance with the characteristic shown in FIG. 22, the actual driving force calculated from the target driving force is subtracted to obtain a difference, and the difference is multiplied by a coefficient k. To set the ratio as follows.

More specifically, an engine torque generated from the engine speed Ne and the accelerator opening θacc is determined, a target driving force is determined from the torque and the vehicle speed V, and a ratio is set so as to be the determined target driving force. Control.

When the result in S204 is NO, S218 is reached.
Then, it is determined that the road is a wet road, and the driving force is controlled at the time of determining the wet road.

Specifically, the target driving force characteristic at the time of judging the wet road shown in the lower part of FIG.
The same ratio setting as in the case of the normal road determination driving force control is performed.
As described above, when the wet road is determined, the ratio is set based on the driving force set to have a target value lower than the driving force control during the normal road control.

Returning to the description of the flow chart of FIG.
The first mountain / city area determination will be described.

FIG. 24 is a subroutine flowchart showing the processing, and FIG. 25 is an explanatory diagram for explaining the processing.

In this control, the concept of a mountain / city area determination function fmount (θn) is used to determine whether the area in which the vehicle is traveling is a mountain or city area. Alternatively, the adjustment gains k1 and k2 of the driving force are appropriately changed. That is, the control responsiveness (the speed at which the control value converges to the target value) is changed according to the driving situation.

FIG. 26 is a graph showing the characteristics of the mountain / city area determination function. The mountain / city determination function is a function indicating the degree of mountain or the degree of city in the area where the vehicle is currently traveling. Specifically, the characteristic shown in FIG. Search by value.

Therefore, the characteristics of the city area determining function are such that when the vehicle is traveling on a mountain road with a steep gradient, the integrated value becomes a large value and the vehicle is traveling on a city with a gentle gradient. At that time, the integrated value was set to a small value.

The target driving force is obtained by retrieving the characteristics shown in FIG. 27 from the mountain / city area determination function. As a result, when the value of the mountain / town area determination function is large, that is, when the mountainous tendency is high, the running resistance and the driving force (engine braking force) match (target driving force = 0), and the change in vehicle speed on a downhill road is small. . Also, when the value of the mountain / city area determination function is small, that is, when the tendency of the city area is high, the target driving force increases.

Therefore, on a downhill in a mountainous area, the target driving force is set to 0, and the running resistance and the engine braking force are made equal to prevent the vehicle speed from rising on the downhill. On the other hand,
On a downhill in an urban area, the same engine braking performance as usual reduces the sense of discomfort with other vehicles traveling forward and backward.

Hereinafter, a description will be given with reference to the flowchart of FIG. 24.
Read long.

Subsequently, the flow proceeds to S302, in which a function for determining a mountain / city area is determined from the long span estimation gradient θ long, and S3 is determined.
It is determined whether or not the mountain / city area determination function obtained by proceeding to 04 is less than the predetermined value A or exceeds the predetermined value B. Here, the predetermined values A and B are an overflow limiter and an underflow limiter, respectively.

When the result in S304 is affirmative, the program proceeds to S306, in which a mountain / city area determination function is held. Also, S3
When the result in S04 is negative, that is, when fmount (θn) is equal to or more than the predetermined value A or equal to or less than B, the process proceeds to S308, and the limit value A or B is set to the mountain / city area determination function fmount (θ
n) and hold.

Subsequently, the flow proceeds to S310, where it is determined whether or not the determined mountain / city area determination function exceeds a predetermined value C. Here, the predetermined value C is a mountain judgment threshold, and the corner resistance R
A value obtained by attenuating the peak hold value of c with time is used. FIG. 28 is a graph showing characteristics of the mountain determination threshold.

As shown in FIG. 28, the mountain judgment threshold C
Is obtained using a value obtained by attenuating the peak hold value of the corner resistance Rc with time. Further, as shown in the figure, the mountain determination threshold value C is set to be inversely proportional to the corner resistance holddown value, whereby even when a relatively gentle slope continues, when there are many sharp corners, When the corner resistance is calculated to be high, the threshold value is set to a small value to make it easier to determine that the mountain is a mountain.

Returning to the flow chart of FIG.
If affirmative at 0, the process proceeds to S312 to determine whether the vehicle is traveling on a mountain road, and proceeds to S314 to determine whether the ratio control during downhill is being performed.

When the result in S314 is affirmative, the program proceeds to S316, in which the target driving force is set to zero. This is because the control is performed such that the vehicle can descend at a constant speed even if the downhill gradient changes so as to suppress the speed change on a mountain road with abrupt changes in undulation.

Subsequently, the flow proceeds to S318, in which the instantaneous margin driving force or the driving force power adjustment gains k1 and k2 are set to predetermined mountain specification values, respectively. If a negative determination is made in S314, the process skips S316 and proceeds to S318.

If the result in S310 is NO, S32 is reached.
The process proceeds to 0 to determine that the vehicle is traveling in an urban area, and proceeds to S322 to determine whether or not the vehicle is performing driving force control (ratio control during descent).

When the result in S322 is affirmative, the program proceeds to S324, in which the target driving force is set to a specified value (for example, a positive value such as 5 kgf). This is because, on a general road downhill in an urban area or the like, a slight acceleration is more convenient due to the flow of other vehicles, and the ratio control is performed in a direction in which a slightly positive driving force is generated.
However, if the brake is operated even once in this state, the specified value is set to 0, and the ratio control is performed so that the speed change is reduced.

In the process of S324, while the ratio at that time is fixed, an appropriate map is used, and even if the target driving force is applied so as to have a linear vehicle speed-engine speed characteristic equivalent to that of the manual transmission. good.

Then, the process proceeds to S326, where the gains k1, k2
Is defined as the city area specified value. If the result in S322 is negative, S324 is skipped and the routine proceeds to S326.

Note that the mountain specified values of the gains k1 and k2 are both set higher than the city specified value, and the ratio control is performed with higher responsiveness when traveling on a mountain road than in city driving.

Since this embodiment is configured as described above, it is possible to realize speed ratio control according to the driver's intention, and to improve drivability. Furthermore, more specifically, by changing the time constant according to the road surface condition and running condition, it is possible to realize a highly responsive and highly accurate gradient estimation, and thus to optimally perform the speed ratio control. As a result, drivability can be improved.

As described above, in this embodiment,
In a control device for an automatic transmission for a vehicle, operating state detecting means (a water temperature sensor 106, a throttle opening sensor 10) for detecting an operating state of the vehicle and an internal combustion engine mounted thereon.
8, a brake switch 112, a vehicle speed sensor 122, a steering sensor 128, etc.), running resistance calculation means (integrated control unit 300, S108 in FIG. 8) for calculating the running resistance of the vehicle based on the detected driving state, Driving force calculating means (integrated control unit 300, S14 in FIG. 2, S104 in FIG. 8) for calculating the driving force output by the vehicle based on the detected driving state, and calculates the driving resistance and the driving force. Gradient estimating means (integral control unit 300, S in FIG.
10, S110 in FIG. 8, speed ratio setting means (integrated control unit 30) for setting a speed ratio based on the estimated gradient
0, S22 to S40 in FIG. 2 and the block diagram in FIG. 13), and a gear ratio determining means (integrated control unit 300, FIG. 2) for determining the gear ratio of the vehicle automatic transmission based on the set gear ratio. S42), and the gradient estimating means obtains a vehicle acceleration from the detected driving state (S134 in FIG. 8), and changes a time constant of data processing required for the estimation based on the obtained vehicle acceleration. The configuration is as follows (S100, S136 in FIG. 8).

When the brake operation is performed, the gradient estimating means estimates a braking force from an estimated value of the gradient before the braking operation and an estimated value of the gradient during the braking operation, and based on the estimated braking force, It was configured to hold the estimated gradient (S114 to S124 in FIG. 8).

The gradient estimating means estimates a corner resistance from the turning force of the vehicle, and corrects the estimated gradient based on the estimated value (S1 in FIG. 8).
06, S142).

In the above description, a gradient may be added as an operation state index as shown in FIG.

[0168]

According to the first aspect of the present invention, it is possible to achieve both the responsiveness of the gradient estimation and the accuracy of the estimation, so that the gear ratio can be optimally controlled and the drivability can be improved. it can. More specifically, by changing the time constant according to the road surface condition and the driving condition, it is possible to realize a highly responsive and highly accurate gradient estimation, and thus it is possible to optimally perform even when controlling the gear ratio, thereby improving drivability. Can be improved.

According to the second aspect, in addition to the above-described effects, the accuracy can be further improved.

According to the third aspect, in addition to the above-described effects, the responsiveness can be further improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram generally showing a control device for a vehicular automatic transmission according to the present invention.

FIG. 2 is a flowchart showing the operation of the apparatus shown in FIG.

3 is an explanatory diagram of a physical quantity state estimation model based on the operation shown in the flowchart of FIG. 2;

FIG. 4 is a block diagram illustrating calculation of a driver request in the block diagram of FIG. 3;

FIG. 5 is a block diagram showing calculation of a negative value of the throttle opening based on the estimated braking force in the block diagram of FIG. 4;

FIG. 6 is a block diagram showing calculation of a stepping time function of a throttle valve (accelerator pedal) and a brake pedal in the block diagram of FIG. 4;

FIG. 7 is a block diagram illustrating calculation of a host vehicle gain in the block diagram of FIG. 3;

FIG. 8 is a block diagram showing a gradient estimating operation of the flow chart of FIG. 2;

FIG. 9 is a block diagram illustrating characteristics of a filter used in a sensor output reading process of the flow chart of FIG. 8;

FIG. 10 is a block diagram showing a corner resistance calculation process in the flow chart of FIG. 8;

FIG. 11 is an explanatory diagram showing indexing and averaging operations of the flow chart of FIG. 2;

12 is a block diagram illustrating calculation of an instantaneous margin driving force used in the uphill control in the flowchart of FIG. 2;

FIG. 13 is a block diagram illustrating climb control in the flowchart of FIG. 2;

FIG. 14 is a graph illustrating characteristics of an instantaneous margin driving force used in the uphill control in the flowchart of FIG. 2;

15 is a graph illustrating characteristics of an instantaneous margin driving force used in the uphill control in the flowchart of FIG. 2;

FIG. 16 is a block diagram illustrating downhill control in the flowchart of FIG. 2;

FIG. 17 is also an explanatory diagram for explaining the descending slope control in the flowchart of FIG. 2;

FIG. 18 is a flowchart illustrating flatland control in the flowchart of FIG. 2;

FIG. 19 is an explanatory diagram illustrating the processing of FIG. 18;

20 is a flowchart showing a subroutine for low-μ road control in FIG. 8;
It is a chart.

FIG. 21 is a time chart for explaining the processing of the flow chart of FIG. 20;

FIG. 22 is a graph showing driving force characteristics used in the processing of the flow chart of FIG. 20;

FIG. 23 is a graph showing target instantaneous margin driving force characteristics used in the processing of the flow chart of FIG. 20;

FIG. 24 is a subroutine flowchart of a mountain / urban area determination operation in the flowchart of FIG. 2;

FIG. 25 is a graph illustrating the processing of the flowchart of FIG. 24;

FIG. 26 is a graph showing characteristics of a mountain / city area determination function fmount θn used in the flow chart of FIG. 24;

FIG. 27 is a graph showing characteristics of a target driving force retrieved from a mountain / city area determination function used in the flow chart of FIG. 24;

FIG. 28 is a predetermined value C used in the flow chart of FIG.
FIG. 6 is a graph showing the characteristics of FIG.

29 is an explanatory diagram showing another example of the indexing and averaging operation of the flow chart of FIG. 2, similar to FIG. 11;

[Explanation of symbols]

Reference Signs List 10 internal combustion engine (main body) (engine (main body)) 14 throttle valve 16 accelerator pedal 18 pulse motor 24 belt-type continuously variable transmission (automatic transmission; CVT. Transmission) 29 vehicle 100 transmission control unit 104 absolute pressure sensor 107 intake temperature Sensor 108 Throttle opening sensor 112 Brake switch 114 Speed sensor 122 Vehicle speed sensor 128 Steering angle sensor 200 Engine control unit 300 Integrated control unit 400 Throttle control unit 500 Low-pass filter

Continuation of the front page (72) Inventor Shuji Nagatani 1-4-1 Chuo, Wako-shi, Saitama F-term in Honda R & D Co., Ltd. (Reference) 3D041 AA32 AA33 AA40 AA66 AB01 AC20 AD00 AD02 AD04 AD05 AD10 AD14 AD23 AD31 AD41 AD47 AD51 AE04 AE36 AE45 AF09 3G093 AA06 BA01 BA15 CB06 CB07 CB09 DA01 DA03 DA04 DA05 DA06 DA07 DB00 DB01 DB05 DB09 DB11 DB15 DB18 DB23 EA09 EB03 EC01 FA07 FA10 FB01 FB02 3J052 AA04 CA21 FA01 GC44 GC13 GC01

Claims (3)

[Claims] 1. A control device for an automatic transmission for a vehicle, comprising: a. Operating state detecting means for detecting an operating state of the vehicle and the internal combustion engine mounted thereon; b. Running resistance calculating means for calculating running resistance of the vehicle based on the detected driving state; c. Driving force calculating means for calculating a driving force output by the vehicle based on the detected driving state; d. Gradient estimating means for estimating the gradient of a traveling road on which the vehicle is traveling, based on the calculated traveling resistance and driving force; e. Speed ratio setting means for setting a speed ratio based on the estimated gradient; and f. Speed ratio determining means for determining a speed ratio of the vehicle automatic transmission based on the set speed ratio, and the gradient estimating means obtains a vehicle acceleration from the detected driving state. A control device for a vehicular automatic transmission, wherein a time constant of data processing required for estimation is changed based on a vehicle acceleration. 2. The brake control device according to claim 1, wherein when a brake operation is performed, the gradient estimating unit estimates a braking force from a gradient estimated value before the brake operation and a gradient estimated value during the brake operation, and based on the estimated brake force. The control device for a vehicle automatic transmission according to claim 1, wherein the estimated gradient is maintained. 3. The vehicle according to claim 1, wherein the gradient estimating unit estimates a corner resistance from a turning force of the vehicle, and corrects the estimated gradient based on the estimated value. Control device for automatic transmission for vehicles.