JP3028982B2 - Control device for automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

It relates FIELD OF THE INVENTION This invention relates a control system for an automatic transmission, and more specifically to estimating the internal of deceleration intention of the driver, as to determine the control value including the estimated value for the parameter Regarding what was done.

[0002]

2. Description of the Related Art In recent years, vehicles have been required to have operability and controllability in response to the driver's sensitivity in addition to the conventional role as a transporter. In the case of controlling an automatic transmission, there is a demand for a device that provides a degree of satisfaction comparable to the operability and controllability of a skilled driver in a manual transmission vehicle even when traveling on a mountain road or the like. For this reason, the present applicant has previously proposed a control device for an automatic transmission to which fuzzy logic is applied in Japanese Patent Application Laid-Open No. 2-3738.

[0003]

To achieve INVENTION Problems to be Solved by the way high quality control of that response well sensibility of the driver described above estimates the internal of deceleration intention of the driver, the estimated value for the parameter It is desirable to determine the control value inclusively. The present applicant has previously therefore, proposes those inferred based on fuzzy logic the deceleration intention of the driver from the engine load and the deceleration amount in Japanese Patent Application No. Hei 2-112816.

[0004] It is an object of the present invention to provide an improvement thereof ,
To provide a control device for an automatic transmission that enables high-quality shift scheduling well matched to the sensibilities of the driver by grasping the deceleration intended more precisely.

[0005]

[0006]

In order to achieve the above object, the present invention relates to a control apparatus for an automatic transmission for controlling the speed ratio of a vehicle internal combustion engine stepwise or steplessly. there are means for determining the operating parameters of the engine, performs a calculation based on fuzzy logic for at least the engine load, vehicle speed and the vehicle speed when the brake operation in the determined was operating parameters inference indicating the deceleration intention of the driver deceleration intent inference value calculating means you calculating the value, the running resistance calculating means for calculating a running resistance of the vehicle from at least the engine load in the determined was operating parameters, the fuzzy
A shift based on fuzzy logic is performed on the inference value calculated based on the logic, the calculated running resistance, and at least the vehicle speed and the engine load among the obtained operating parameters to determine the gear ratio. Ratio determining means; and
The drive mechanism is configured to drive the speed change mechanism based on the determined speed ratio.

[0007]

Use Rutotomoni, the vehicle speed and the vehicle speed at the time of brake operation using the [action] essential engine load to the inference of internal a deceleration intention of the driver
To properly calculate the inference value indicating the intention to decelerate
Since the control value is determined by adding the inference value to the inference parameter, it is possible to realize shift control that is well suited to human sensitivity. Further, even when carried out on the basis of a full Ajii inference fuzzy production rules by performing the double reasoning, realize the shift control that matches well to sensitive human
Is possible, the representation of the antecedent of each rule can be simply described. Further, the running resistance is added to the speed ratio calculation parameter.
Because it also adds resistance, it can be strange when driving in mountainous areas.
Inconvenience such as frequent change of the speed ratio does not occur.
No.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIGS. 1 to 14 show a first embodiment of the present invention, and show an example in which the present invention is embodied in a device for controlling the speed ratio of a stepped transmission.

FIG. 1 is a schematic diagram showing the entire control device. Referring to FIG. 1, reference numeral 10 indicates a main body of the internal combustion engine. An intake passage 12 is connected to the engine body 10, and an air cleaner 14 is attached to a tip end side of the intake passage 12.
The intake air introduced from the air cleaner 14 is adjusted in flow rate through a throttle valve 16 that operates in conjunction with an accelerator pedal (not shown) on the floor of the vehicle driver's seat and reaches the engine body. A fuel injection valve (not shown) is provided at an appropriate position near a combustion chamber (not shown) of the intake passage 12 to supply fuel,
The intake air is mixed with fuel, enters the combustion chamber, is compressed by a piston (not shown), is ignited via a spark plug (not shown), explodes, and drives the piston. The driving force of the piston is converted into a rotational motion and taken out from the engine output shaft 18.

A transmission 20 is connected to a rear stage of the engine body 10, and an engine output shaft 18 is connected to a torque converter 22 thereat and connected to a pump impeller 22a. Turbine runner 22 of torque converter 22
b is connected to a main shaft (transmission input shaft) 24. A counter shaft (transmission output shaft) 26 is juxtaposed on the main shaft 24. First and fourth speed gears G1 to G4 and a reverse gear GR are provided between the two shafts. Hydraulic clutches CL1 to CL4 are provided correspondingly (the reverse gear clutch is not shown). A one-way clutch 28 is mounted on the first speed gear G1. A, A in the middle of the oil passage 30 connecting the hydraulic clutch group and a hydraulic source (not shown).
B2 shift valves 32 and 34 are inserted, and these shift valves change the position by energizing / de-energizing the electromagnetic solenoids 36 and 38 to control the supply and discharge of the pressure oil to and from the clutch group. Reference numeral 40 indicates a lock-up mechanism of the torque converter 22. The counter shaft 26 is connected to a differential device 44 via a propeller shaft 42.
And a differential device 44 is connected to wheels 48 via a drive shaft 46,
The engine output, which has been shifted through these, is transmitted to the wheels 48.

A throttle sensor 50 comprising a potentiometer or the like for detecting the opening of the throttle valve 16 is provided in the vicinity of the throttle valve 16 in the intake passage 12, and is connected to a rotating part such as a distributor (not shown) near the engine body 10. Is a crank angle sensor 52 composed of an electromagnetic pickup or the like.
Is provided to detect a crank angle position of the piston and output a signal at every predetermined crank angle. The engine intake passage 12
The intake pressure sensor 5 is located at an appropriate position downstream of the throttle valve 16.
4 is provided to detect the intake pressure as an absolute value. Furthermore, a brake pedal (not shown) installed on the floor of the driver's seat of the vehicle
, A brake switch 56 for detecting depression of a brake pedal is provided, and a vehicle speed sensor 58 including a reed switch is provided at an appropriate position on the drive shaft 46 to output a signal at each predetermined rotation angle of the drive shaft. I do. These outputs are sent to the transmission control unit 60. Further, the output of the range selector switch 62 for detecting the selected position of the range selector is also sent to this control unit.

FIG. 2 is a block diagram showing details of the transmission control unit 60. As shown in the figure, an analog output of the throttle sensor 50 and the like is supplied to a level conversion circuit 6 in the unit.
After being input to 8 and amplified, it is input to the microcomputer 70. The microcomputer 70 includes an input I / O 70a, an A / D conversion circuit 70b, a CPU 70
c, ROM 70d, RAM 70e, and output I / O 70f
And a group of registers and counters (the last two are not shown) and the like. The output of the circuit 68 is input to an A / D conversion circuit 70b and converted into a digital value,
e. The digital output of the crank angle sensor 52 and the like is also shaped by the waveform shaping circuit 72 before the input I
The data is input into the microcomputer via the / O 70a and stored in the RAM 70e. The CPU 70c determines the shift position (speed ratio) as described later based on the input value and the calculated value calculated from the input value, sends the shift position from the output I / O 70f to the first and second output circuits 74 and 76, and outputs the electromagnetic solenoids 36 and 38. To excite and switch or hold the gear.

Next, the operation of the control device will be described with reference to the flowcharts shown in FIG.

Here, prior to a specific description, the features of the control device of the embodiment will be described briefly with reference to FIG.
In this control device, a first fuzzy inference is performed from the throttle opening and the like to determine a driver's intention to decelerate, and a second fuzzy inference is performed from parameters including the inference value to determine a gear ratio. . 5 to 7 show a group of fuzzy production rules used for the inference. Among them, rules 1 to 6 are rules for general driving conditions (referred to as “base rules”), and rules 7 to 11 are rules for limited driving conditions such as uphill (“extra”). Rules "). Among them, rules 10 to 11 use the deceleration intention as one of the inference parameters. Rules 12 to 15 are rules for inferring the deceleration intention, that is, rules used in the first fuzzy inference. In the fuzzy inference, various operation parameters used in these rule groups are obtained, and an output value is determined by inference using a membership function corresponding to an operation parameter defined in the rule. Since the output (inference) value often includes a decimal part such as "0.8", the shift position (gear position) is specified by converting to an integer, and a limit check is performed so that the maximum position is not exceeded. And outputs it to the electromagnetic solenoid.

Therefore, returning to FIG. 3, first, in S10, input calculation, that is, parameters used in fuzzy inference are detected and calculated. Rules 1 to 11 as fuzzy inference parameters include vehicle speed V [km / h], current shift position (gear position), throttle opening θTH [degrees: 0 to 84 degrees (WO
T)], running resistance [kg], and intention to decelerate. Rules 12 to 15 are based on the vehicle speed VBRK
[Km / h], vehicle acceleration α [m / s ² ], throttle opening θTH, gradient resistance RG [kg], and vehicle speed V. Among these, the vehicle speed V and the like are calculated from the sensor output value, and the current shift position is mainly determined from the excitation pattern of the electromagnetic solenoid, but the running resistance is determined by a special method.

FIG. 8 is a subroutine flowchart showing the calculation of the running resistance. In this embodiment, the running resistance is obtained by calculation without using a torque sensor or the like. That is, the power performance of the vehicle is calculated from the equation of motion as follows: driving force F−running resistance R = (1 + equivalent mass) × (body weight / gravity acceleration G) × acceleration α [k
g]. . . . . . . . . . . . It can be expressed as. The driving force F and the (total) running resistance R
Is the driving force F = (torque T × total reduction ratio G / R × transmission efficiency η) /
Tire effective radius r [kg] Running resistance R = (rolling resistance μ0 + gradient sin θ) × vehicle weight Wr + air resistance (μA × V ² ) [k
g]. . . . . . . . . . . . . . (In the above, the equivalent mass (equivalent mass coefficient) is a constant, and V is the vehicle speed.) In the formula, the vehicle weight W that changes according to the traveling state includes a vehicle weight W that varies according to the number of occupants and the amount of loaded cargo, and a gradient that varies according to the traveling road surface.
sin θ, which is all included in the running resistance. Therefore, by transforming the formula, the running resistance R can be obtained by the following equation: running resistance R = driving force F − ｛(1 + equivalent mass) × body mass M × acceleration α｝ [kg] (where body mass M = body weight W
/ Gravity acceleration G).

The flow chart of FIG. 8 will be described on the premise of the above. First, in S100, the RO shown in FIG.
A map stored in M is searched from the engine speed and the intake pressure to estimate the torque. The characteristics of this map are set separately according to the intake pressure as shown in the figure. Next, in step S102, the torque ratio t is searched by searching the table showing the characteristics in FIG. 10, and the torque is corrected by multiplying the torque T. This search is performed by obtaining the speed ratio e of the torque converter from the engine speed and the output speed (speed) of the torque converter turbine, and searching the table in FIG. 10 from the value. next,
Proceeding to S104, a moving average calculation is performed as shown in FIG. 11 to correct the delay until the intake pressure change becomes the engine output change, and after it is confirmed in S106 that the brake operation is not performed, the process proceeds to S108. The total running resistance R is calculated from the above equation. When it is determined in S106 that the brake is being operated, the braking force is applied and it is difficult to obtain an accurate value.
Proceeding to S110, the previously calculated value is used. Then, S1
Proceeding to 12, the running resistance R / L on a flat road is calculated from the total running resistance R.
Is subtracted to calculate the gradient resistance RG. The running resistance on a flat road is set in advance through an experiment, stored in the ROM, and retrieved from the vehicle speed V. FIG. 12 shows the characteristics.

In S10 of FIG. 3, the above parameters are calculated and detected. As shown in FIG. 13, the vehicle speed VBRK at the time of the brake operation means a decrease in the vehicle speed from the time t0 when the brake is depressed, and is obtained from the vehicle speed while detecting the brake operation and measuring the elapsed time.

Then, the program proceeds to S12, in which the first fuzzy inference is performed to infer the deceleration intention DEC, and to S14, the current inference value is added to the previous cumulative value DECn-m to be updated. The shift position is determined by performing the second fuzzy inference from the above-mentioned operation parameters including the deceleration intention DEC, and the fuzzy inference itself is based on the technology proposed by the present applicant (Japanese Patent Application No. $ 112816
), And the inference method itself is not the gist of the present application, so that it will only be briefly described with reference to FIG. First, for each rule, the detection (calculation) parameter is applied to the corresponding membership function in the antecedent part (IF part) to read the value on the vertical axis (membership value), and the minimum value is used as the conformity of the antecedent part. . Subsequently, the output value (position and weight of the center of gravity) of the consequent part (conclusion, THEN part) of each rule is weighted by the degree of conformity of the antecedent part to obtain an average value.
That is, fuzzy operation output = {(conformity of each rule) × (position of the center of gravity of output) × (weight)} / {(conformity of each rule) × (weight)}. Note that the output value of the conclusion may be truncated based on the degree of conformity of the antecedent part of each rule using a known method, and then the waveform may be synthesized to determine the center of gravity to determine the fuzzy operation output.

Here, the explanation about the inference rule of the deceleration intention shown in FIG. 7 is supplemented a little. The reason why the internal intention of the driver is inferred in the first place is that in the rule of FIG. , Deceleration, etc., are intended for limited driving situations. Of these, climbing is the driving environment in which the vehicle is located, whereas deceleration is a change in the driving situation caused by the driver's own intention. Often. Therefore, rather than grasping such driving conditions only from physical quantity parameters, it is better to guess the driver's inner intention and comprehensively infer from the parameters including the inner intention, so that control that is more suited to human sensitivity This is because it is considered desirable for realizing the above.

Next, the inference itself will be described with reference to FIG. 14. The internal intention of the driver can only be estimated from the operating state and operating state of the equipment operated by the driver.
In addition, as for the estimation result, there are only three states of intention to decelerate, intention to decelerate, intention to decelerate, or no intention to decelerate. This figure is a state transition diagram, in which an accelerator pedal (throttle valve) and a brake are selected as operating devices of the driver, and the deceleration DEC and the cruising CR are selected as operating conditions.
When looking at U and the acceleration ACC, various combinations of these parameters can be considered as shown in the figure. Here, for example, (OFF, ON, DEC) indicates that the accelerator is released, the brake is being decelerated, and the asterisk symbol indicates a wild card representing all the states. The driver's internal intention can be known only by the driver himself, but the intention is to decelerate when the accelerator is released and the brake is depressed and the vehicle is decelerating, and decelerate when the accelerator is depressed. Judgment that there is no intention is minimally possible. At the same time, this is the maximum judgment, and unless the brake is depressed, it cannot be declared that there is intention to decelerate, even if the accelerator is released and deceleration, even if the accelerator is released and the brake is depressed It is difficult to conclude that there is no intention to decelerate while cruising or accelerating. In the above, the rules were created as a premise in the earlier application, but in the present embodiment, the driving conditions are classified in more detail by further adding the gradient resistance and the vehicle speed to the parameters on the premise of the above.

That is, in the case of the rule 12, the gradient resistance is a negative value, that is, a downhill is scheduled. Since the vehicle coasts when descending a slope, it is considered that the driver's intention is to shift down to use the engine brake when the vehicle decelerates a little. Note that the deceleration intention DEC is determined by rules 10 to 11 in FIG.
As shown in FIG. 7, as the value approaches "1.0", a shift is determined in the down direction. Rules 12 and 13 are intended for the case where the gradient resistance is a positive value, that is, traveling on a flat road or an uphill road. Among them, rule 12 sets the membership function of the vehicle speed to be large on the low speed side, that is, at low speed on the flat (uphill) road. The driving state is scheduled, and the rule 13 is set to be large on the high-speed side, and the driving state on the same road surface at high speed is scheduled.
Rule 12 differs from rule 11 in that no coasting on a downhill road is planned, so that the intention of deceleration is not seen unless the vehicle is decelerated to some extent. Furthermore, in Rule 13, it is considered that the driver feels a great deceleration even if the brake is operated a little because the vehicle is traveling at high speed, and it is not necessary to take in the intention of the driver to decelerate unless the vehicle is greatly decelerated.

In the flow chart of FIG.
Proceeding to 18, perform integer conversion and limit check, and
Then, the shift position after the check is output. As described above, the integer conversion / limit check work often includes a decimal part because the fuzzy inference value is a weighted average value, and the shift output value often includes a decimal part such as “0.8”. The gear position to be shifted is specified, and when the shift command value exceeds, for example, the fourth speed, the speed is limited to the fourth speed. The details are described in the earlier application, and the gist of the present invention is as follows. That's not the place, so we'll stop at this level of explanation.

In this embodiment, the driver's intention to decelerate is fuzzy inferred from the throttle opening and the like, and the shift position is fuzzy inferred from the parameter group by adding the inferred value. High-quality shift scheduling that is well suited can be realized. Also, in the deceleration intention inference, a rule is created by classifying the driving situation by adding the gradient resistance and the vehicle speed to the parameters, so that the driver's intention can be more accurately estimated. Furthermore, since the double inference format was used, the antecedent part (IF part) of each rule
Can be described in a simpler expression.

In the above embodiment, an example of inferring the intention of deceleration has been described. However, the present invention is not limited to this.
It is also possible to infer fuel economy intention and the like. In addition, although the driving situation is classified based on the gradient resistance and the vehicle speed, it is also possible to classify the shift for each shift using the shift position as a parameter. Although the inference method based on the fuzzy production rules is used, inference based on fuzzy relations may be used. Although the engine load is determined from the throttle opening, an accelerator opening (accelerator pedal depression amount) or the like may be used. Although the double inference format is used, the present invention is not limited to this, and the speed ratio may be determined using another control method such as PID control. Further, the example in which the speed ratio of the stepped transmission is controlled stepwise has been described, but the speed ratio of the continuously variable transmission may be continuously controlled.

FIG. 15 shows a second embodiment of the present invention, and shows an example in which the present invention is applied to an apparatus for controlling a throttle opening degree using a pulse motor.

In the figure, an accelerator pedal 80 is connected to one end of an arm 82 having a rectangular shape in cross section, and is connected to a floor 84 of a vehicle.
Is rotatably installed by a shaft 86. A return spring 88 is elastically mounted on the other end of the arm 82 to urge the accelerator pedal 80 to the idle position. The shaft 86 is provided with an accelerator opening sensor 90 composed of a potentiometer, and outputs a voltage value according to the amount of depression of the accelerator pedal 80, that is, the rotation angle from the idle position around the shaft 86. A rotary shaft (not shown) of a pulse motor 94 is connected to a shaft 92 of the throttle valve 16, and opens and closes the throttle valve 16 according to the rotation. The opening is the throttle sensor 50
And sent to the throttle control unit 96. An intake pressure sensor 54 and a crank angle sensor 52 are also provided, and transmit detected values to a throttle control unit 96. The throttle control unit 96 controls the throttle opening in accordance with predetermined characteristics based on the detected values. In such a configuration, the deceleration intention is fuzzy inferred according to the example shown in the first embodiment, and the inferred value is obtained. It is also possible to determine the throttle opening from the included parameters.

FIG. 16 shows a third embodiment of the present invention, and shows an example in which deceleration intention inference is applied to fuel injection control.
In the fuel injection control, the basic injection amount (indicated by injection time) is determined from the engine speed and the engine load, and in a predetermined area, fuel cut is performed when the vehicle is decelerating, as shown in FIG. Has been reduced. In the fuel cut, a predetermined delay time expires after satisfying a condition that the throttle opening is fully closed and the load and the engine speed are within a predetermined range. In the same figure, the fuel cut region is indicated by reference numeral A. In such a case, the fact that the intention of deceleration is greater than or equal to a certain value is included in the fuel cut condition. Fuel cut can be performed, and fuel efficiency can be improved.

[0030]

According to a first aspect of the present invention, there is provided a control device for an automatic transmission for controlling a speed ratio of a vehicle internal combustion engine in a stepwise or stepless manner. at least the engine load in the obtained operating parameters, performs a calculation based on fuzzy logic for the vehicle speed and the vehicle speed when the brake operation, deceleration intent inference value calculating means you calculating an inference value indicating deceleration intention of the driver, running resistance calculating means for calculating a running resistance of the vehicle from at least the engine load in said determined operating parameters, the fuzzy
A gear ratio that determines a gear ratio by performing a calculation based on fuzzy logic with respect to an inference value calculated based on logic, the calculated running resistance, and at least the vehicle speed and the engine load among the calculated operating parameters. determining means, and, since as constituting a driving means for driving the speed change mechanism on the basis of the determined gear ratio, can be well reflect the internal of deceleration intention of the person to determine the gear ratio, human Speed change control that matches well the sensitivity of the vehicle. Also <br/>, when carried out on the basis of a full Ajii inference in fuzzy production rules, by performing the double inference, good sensibility of the people
It is possible to realize a shift control that matches well, and to simply describe the antecedent of each rule. In addition,
Since the running resistance is also added to the speed ratio calculation parameter,
Do not change the gear ratio frequently even when traveling on the ground.
No inconveniences occur.

[0031] In the second aspect, wherein, prior Symbol decrease deceleration intent inference value calculating means, and as configured to further calculating an inference value indicating deceleration intention of the driver by adding the computed running resistance since, in addition to the effects described in claim 1 wherein, better,
It is possible to infer the deceleration intention of the person, it is possible to realize a shift control to better match the sensibility of the people.

[0032] In the third aspect, wherein, the running resistance exerted to the operation, since the composed as a grade resistance, to realize a high-quality shift scheduling to have a similar effect as claimed in claim 2, wherein Can be.

[0033]

[0034]

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an overall control device of an automatic transmission according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a shift control unit in FIG.

FIG. 3 is a main flow chart showing the operation of the control device.

FIG. 4 is an explanatory block diagram showing features of the control device.

FIG. 5 is an explanatory diagram showing rules 1 to 6 in a fuzzy production rule group used in the second fuzzy inference of the flow chart of FIG. 3;

FIG. 6 is an explanatory view showing rules 7 to 11 in a fuzzy production rule group used in the second fuzzy inference of the flow chart of FIG. 3;

FIG. 7 is an explanatory diagram showing a fuzzy production rule group for inferring a deceleration intention used in the first fuzzy inference of the flow chart of FIG. 3;

FIG. 8 is a subroutine flowchart showing the operation of calculating the running resistance in the input calculation of the flowchart of FIG. 3;

FIG. 9 is an explanatory diagram showing characteristics of a map used for torque search in the flow chart of FIG. 8;

FIG. 10 is an explanatory diagram showing characteristics of a table used in a torque ratio search in the flow chart of FIG. 8;

FIG. 11 is an explanatory diagram showing a calculation operation of a corrected torque average value in the flow chart of FIG. 8;

FIG. 12 is an explanatory diagram showing characteristics of a map used for searching for running resistance on a flat road in the flow chart of FIG. 8;

FIG. 13 is an explanatory diagram showing a vehicle speed at the time of a brake operation in the input calculation of the flow chart of FIG. 3;

14 is an explanatory diagram showing a state transition diagram of a deceleration intention, which is a premise for creating a rule in FIG. 7;

FIG. 15 is an overall schematic diagram of a throttle control device showing a second embodiment of the present invention.

FIG. 16 is an explanatory diagram showing a fuel cut region according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Internal combustion engine main body 18 Engine output shaft 20 Transmission 22 Torque converter 24 Main shaft (mission input shaft) 26 Counter shaft (mission output shaft) 36, 38 Electromagnetic solenoid 60 Shift control unit 70 Microcomputer 96 Throttle control unit

Continued on the front page (51) Int.Cl. ⁷ Identification code FI F16H 59:54 59:66 (72) Inventor Yukihiko Suzaki 1-4-1, Chuo, Wako-shi, Saitama Pref. References JP-A-63-246546 (JP, A) JP-A-2-3739 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 61/00-61/10

Claims (3)

(57) [Claims] 1. A control device for an automatic transmission for controlling the speed ratio of a vehicle internal combustion engine stepwise or steplessly, comprising: a. Means for determining operating parameters of the engine; b. At least the engine load in said determined operating parameters, performs a calculation based on fuzzy logic for the vehicle speed when the vehicle speed and brake operation, deceleration intent inference value calculation you calculating an inference value indicating deceleration intention of the driver Means, c. Running resistance calculating means for calculating the running resistance of the vehicle from at least the engine load in the obtained operating parameters; d. An inference value calculated based on the fuzzy logic ,
Speed ratio determining means for performing a calculation based on fuzzy logic on the calculated running resistance and at least the vehicle speed and the engine load among the obtained operating parameters to determine a speed ratio, and e. A control unit for driving a transmission mechanism based on the determined transmission ratio. 2. A pre-Symbol decrease deceleration intent inference value calculating means further claim 1, wherein said computing the inference value the addition of the calculated running resistance shows the deceleration intention of the driver Automatic transmission control device. 3. The control device for an automatic transmission according to claim 2, wherein the running resistance added to the calculation is a gradient resistance.