JPH0526339A - Speed change control device for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent bad speed change control attributed to the difference between required and actual quantities of intake air by reducing a correction factor representing the ratio of required quantity of intake air to actual quantity of intake air where required and actual quantities of intake air are small. CONSTITUTION:A transmission control computer 34 switches and controls the speed change stages of an automatic speed change gear 68 according to predetermined speed change conditions depending upon the quantity of intake air, the opening of a throttle valve, the number of revolutions of an engine, and velocity. To control speed changes properly, a correction factor K1 representing the ratio of required quantity of intake air to actual quantity of intake air which is determined using the opening of a throttle valve and the number of revolutions of the engine is determined. However, where the required and actual quantities of intake air are small, a modified correction factor MK is determined so that the amount of correction by the correction factor K1 will be smaller and is used to correct shift up or down velocity. This allows preventing bad speed change control attributed to the difference between required and actual quantities of intake air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for an automatic transmission, and more particularly to a shift control device for performing a correction according to an actual intake air amount when performing shift control according to a predetermined shift condition. It is about improvement.

[0002]

2. Description of the Related Art As a shift control device for an automatic transmission,
(A) Conventionally, the one provided with the shift control means for automatically switching the shift stage of the automatic transmission according to the value of the actual shift parameter according to a predetermined shift condition has been widely used. For example, FIG. 5 and FIG. 6 are examples of the upshift-side shift map and the downshift-side shift map as the shift conditions, which are “1st”, “2nd”, and “3r”.
The present invention relates to an automatic transmission having four forward shift speeds of "d" and "4th", and vehicle speed V and throttle valve opening TA are defined as shift parameters, respectively. Then, according to the current shift speed, the vehicle speed V and the throttle valve opening TA, it is determined whether or not the shift speed is switched according to the shift map.

By the way, the above-mentioned throttle valve opening is used to control the shift of the shift speed as a load condition of the engine. In recent years, however, the fuel consumption of the engine has been reduced and the operating condition of the vehicle has been changed. An engine equipped with various variable mechanisms such as a variable valve timing mechanism that changes the opening / closing timing of intake / exhaust valves and an idle speed control mechanism that changes the engine speed during idle in order to obtain the optimum engine output. Has been proposed, the throttle valve opening does not always faithfully represent the load state of the engine. Further, since the air pressure is different between the flatland and the highland, the actual intake air amount is different even if the throttle valve opening is the same, and the load state of the engine is changed accordingly. Therefore, (b) the required intake air amount, that is, the calculated intake air amount is obtained based on the engine speed and the throttle valve opening, and
Correction coefficient calculating means for calculating a ratio of the actual intake air amount detected by the intake air amount detecting means and the required intake air amount as a correction coefficient; and (c) the shift condition and the actual shift air condition according to the correction coefficient. It has been proposed to provide a correction unit that corrects any of the values of the shift parameter to optimize the shift control. The device described in Japanese Patent Application Laid-Open No. 2-266155 is an example thereof, and the required intake air amount Qc is obtained from a predetermined data map based on the engine speed NE and the throttle valve opening TA, and the air flow is also determined. From the actual intake air amount Qm measured by the meter and the required intake air amount Qc, the correction coefficient K1 =
After calculating Qc / Qm and correcting the throttle valve opening TA by multiplying the actual throttle valve opening TA by the correction coefficient K1, the shift control is performed according to the shift map according to the correction value and the actual vehicle speed V. Alternatively, a shift map is selected according to the correction coefficient K1, and shift control is performed according to the actual throttle valve opening TA and the vehicle speed V according to the selected map.

[0004]

However, in the shift control device which corrects the shift condition and the value of the shift parameter by using the correction coefficient K1 (= Qc / Qm) in this way, the engine speed NE and the throttle valve opening are set. The required intake air amount Qc and the intake air amount Qm are to some extent due to a measurement error of the degree TA and the intake air amount Qm, or a calculation error when obtaining the required intake air amount Qc from the engine speed NE and the throttle valve opening TA. It is unavoidable that an error is introduced, and in particular in a region where the required intake air amount Qc and intake air amount Qm are small, the correction coefficient K1 is small even if the error is small.
There is a risk that the gear shift control may be deteriorated if the correction is performed according to the correction coefficient K1.

The present invention has been made in view of the above circumstances, and its object is to obtain a required intake air amount Qc.
This is to prevent the deterioration of the shift control due to the error of the intake air amount Qm.

[0006]

In order to achieve such an object, the required intake air amount Q such that the error in the required intake air amount Qc and the intake air amount Qm is greatly reflected in the correction coefficient K1.
In the region where c and the intake air amount Qm are small, the correction by the correction coefficient K1 may be small.
As shown in the claim correspondence diagram of FIG. 1, (a) shift control means for automatically switching the shift stage of the automatic transmission according to the value of an actual shift parameter according to a predetermined shift condition; ) The required intake air amount is obtained based on the engine speed and the throttle valve opening, and the ratio between the actual intake air amount detected by the intake air amount detecting means and the required intake air amount is calculated as a correction coefficient. A shift control device for an automatic transmission, comprising: a correction coefficient calculating means; and (c) a correction means for correcting either the shift condition or the value of an actual shift parameter according to the correction coefficient. In a region where the required intake air amount or the actual intake air amount is small, the correction factor is corrected so that the correction amount by the correction factor is substantially smaller than that in the region where the required intake air amount is small. Characterized in that a stage.

[0007]

That is, the shift control device for an automatic transmission according to the present invention is designed so that the error in the required intake air amount or the actual intake air amount is greatly reflected in the correction coefficient. In the region where the air amount is small, the correction factor is corrected by the correction factor correction means so that the correction amount by the correction factor is substantially smaller than that in the region where the air amount is large. As a result, in a region where the required intake air amount and the actual intake air amount are large and the influence of these errors on the correction coefficient is relatively small, substantially the same correction as before is performed, and the variable valve timing mechanism and idle rotation are performed. The appropriate shift control is performed regardless of the operating state of various variable mechanisms such as the number control mechanism or the change in atmospheric pressure, while the required intake air amount and the actual intake air amount are small, and the error correction coefficient for these errors In the region where the influence is large, the correction amount by the correction coefficient is reduced, and deterioration of the shift control due to errors in the required intake air amount and the actual intake air amount is prevented.

The correction coefficient correction means is configured to correct the correction coefficient in accordance with, for example, the required intake air amount or the actual intake air amount, but at least the required intake air amount and the actual intake air amount. If the correction coefficient is corrected so that the correction amount by the correction coefficient becomes small in the area where the amount is small, the correction coefficient is always corrected according to the required intake air amount or the actual intake air amount. Need not be

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, in a combustion chamber 12 of a gasoline engine 10, an air cleaner 14, an air flow meter 16, an intake passage 18, a throttle valve 20, a bypass passage 22, a surge tank 24, an intake manifold 26,
And air is taken in through the intake valve 28,
Fuel gas injected from a fuel injection valve 30 provided in the intake manifold 26 is mixed with the air. The air flow meter 16 corresponds to an intake air amount detecting means for detecting an actual intake air amount, and in the present embodiment, a movable vane type is used, and the intake air amount indicating the actual intake air amount Qm is used. Quantity signal S
Qm is supplied to the engine control computer 32 and the transmission control computer 34. The throttle valve 20 is mechanically connected to an accelerator pedal of an automobile (not shown) and is adapted to continuously change the intake air amount by being opened / closed in accordance with the operation amount of the throttle valve 20. The valve 20 is provided with a throttle position sensor 36, and supplies a throttle valve opening signal STA representing the throttle valve opening TA to the engine control computer 32 and the transmission control computer 34. The bypass passage 22 is disposed in parallel with the throttle valve 20, and the bypass passage 22 is provided with an idle speed control valve 38. The engine control computer 32 controls the opening degree of the idle speed control valve 38. Is controlled to adjust the amount of air that bypasses the throttle valve 20 and control the engine speed during idling. The injection timing and the injection amount of the fuel injection valve 30 are also controlled by the engine control computer 32. An intake air temperature sensor 40 that measures the temperature of intake air is provided upstream of the air flow meter 16 and supplies a signal representing the intake air temperature to the engine control computer 32.

The engine 10 includes an intake valve 28 and an exhaust valve 4
2, a piston 44, and an ignition plug 46. The ignition plug 46 generates an ignition spark by a high voltage supplied from an igniter 48 controlled by the engine control computer 32 through a distributor 50. , The crankshaft is rotated by exploding the mixed gas in the combustion chamber 12 and moving the piston 44 up and down. The intake valve 28 and the exhaust valve 42 are adapted to be opened and closed by a cam shaft that is rotationally driven in synchronization with the rotation of the crankshaft, and a variable valve timing mechanism 52 controlled by the engine control computer 32 The opening / closing timing is adjusted by changing the rotational phase of the cam shaft and the crank shaft. Then, the exhaust gas burned in the combustion chamber 12 is discharged from the exhaust valve 42 to the atmosphere through the exhaust manifold 54, the exhaust passage 56, and the catalyst device 58. The engine 10 has a water temperature sensor 6 for measuring the engine cooling water temperature.
0 is provided, and a signal representing the engine cooling water temperature is supplied to the engine control computer 32, and the exhaust manifold 54 is provided with an oxygen sensor 62 for detecting the oxygen concentration in the exhaust gas. The engine control computer 32 is supplied with a signal representing the oxygen concentration. Further, the distributor 50 is provided with a rotation angle sensor that generates a pulse in synchronization with the rotation of the crankshaft, and supplies the pulse signal to the engine control computer 32. The engine speed signal SNE indicating the engine speed NE of the engine 10 is also supplied to the transmission control computer 34.

The engine control computer 32 and the transmission control computer 34 are both C
PU, RAM, ROM, I / O interface circuit, A
A / D converter and the like are used to perform signal processing according to a program stored in advance in the ROM while utilizing the temporary storage function of the RAM. A signal indicating ON / OFF of the air conditioner is supplied from the switch 64, and the transmission control computer 3
4 is the shift lever operation position of the driver's seat, that is, "P
(Parking), "N (Neutral)", "D (Drive)", "1 (First)", "2 (Second)", "R (Reverse)", etc. are supplied from the shift select sensor 66. To be done. The transmission control computer 34 also includes automatic transmissions 68 that change the rotational speed of the engine 10 in four forward speeds and one reverse speed, ie, "1st", "2nd", "3r".
The gear position signal SG indicating which of "d" and "4th" is supplied from the shift position switch 70, and the vehicle speed signal SV representing the rotation speed of the output shaft of the automatic transmission 68, that is, the vehicle speed V is the vehicle speed. It is supplied from the sensor 72. The automatic transmission 68 is a well-known one that includes a planetary gear device, a hydraulic friction engagement device, and the like. By changing the engagement state of the hydraulic friction engagement device by switching the hydraulic circuit, The four forward gears and the one reverse gear are formed. Necessary information is transmitted and received between the control computers 32 and 34, and at least any of the intake air amount signal SQm, the throttle valve opening signal STA, and the engine speed signal SNE is transmitted. It may be supplied to the control computer 32 or 34. It is also possible to incorporate various other signals representing the operating state of the vehicle, such as ON / OFF of the brake pedal, the steering angle of the steering wheel, the gradient of the road surface, and the exhaust temperature, for use in engine control or transmission gearshift control. Is.

Then, the engine control computer 32 uses the intake air amount Qm, the throttle valve opening TA,
Engine speed NE, engine 10 cooling water temperature, intake air temperature, oxygen concentration in exhaust passage 56, air conditioner ON
In accordance with −OFF or the like, for example, the fuel gas injection by the fuel injection valve 30 is performed based on a predetermined data map or an arithmetic expression so as to reduce the fuel consumption and the harmful exhaust gas while securing the required engine output. Quantity and timing of injection,
The ignition timing by the igniter 48, the idle speed by the idle speed control valve 38, and the opening / closing timing of the intake / exhaust valves 28, 42 by the variable valve timing mechanism 52 are controlled. Further, the transmission control computer 34 uses the intake air amount Qm and the throttle valve opening T
Depending on A, the engine speed NE, the vehicle speed V, the gear position of the automatic transmission 68, the shift lever operation position, and the like, the gear position of the automatic transmission 68 is switched and controlled according to predetermined gear shifting conditions. Hereinafter, the shift control in the case where the shift lever operation position is “D” and the shift is performed in the four forward gears will be specifically described with reference to the flowcharts of FIGS. 2 to 4.

First, in step S1, a gear position signal SG representing the current gear position of the automatic transmission 68 is read, and in step S2, a throttle valve opening signal STA representing the throttle valve opening TA and a vehicle speed representing the vehicle speed V. The signal SV is read. In a succeeding step S3, it is determined whether or not the current shift speed represented by the shift speed signal SG read in the above step S1 is "4th". The following steps regarding the downshift are executed, but in the case of NO, the steps regarding the upshift following step S4 are executed. In step S4, as shown in FIG.
Vehicle speed V and throttle valve opening T
Three types of upshift side shift maps stored in advance with A as a shift parameter, that is, “1st → 2nd”,
From the shift maps for “2nd → 3rd” and “3rd → 4th”, a shift map for upshifting from the current shift stage is selected. For example, when the current gear is “3rd”, “(3rd) → 4th” in (c)
Is selected. Also, step S5
Then, the shift-up vehicle speed Vu is obtained from the selected shift map and the current throttle valve opening TA represented by the throttle valve opening signal STA read in step S2, and in step S6, the shift-up vehicle speed Vu is corrected with a correction correction coefficient. The corrected shift-up vehicle speed MVu is calculated by multiplying MK. Then, in the next step S7, the corrected shift-up vehicle speed MVu is compared with the current vehicle speed V represented by the vehicle speed signal SV read in step S2, and upshift is performed depending on whether MVu ≦ V or not. If it is determined that MVu ≦ V, the shift stage of the automatic transmission 68 is switched to upshift in step S13. If V <MVu, steps S8 and thereafter are executed.

In step S8, it is judged whether or not the current shift speed read in in step S1 is "1st". If NO in step S9, three types of downshift-side shift maps stored in advance as vehicle speed V and throttle valve opening TA as shift parameters, that is, "2nd → 1st", "3r
A shift map for downshifting from the current shift stage is selected from shift maps for "d → 2nd" and "4th → 3rd". For example, if the current gear is "3
In the case of "rd", the shift map for "3rd → 2nd" in (b) is selected. Further, in step S10, the shift-down vehicle speed Vd is obtained from the selected shift map and the current throttle valve opening TA indicated by the throttle valve opening signal STA read in step S2, and in step S11, the shift-down vehicle speed Vd. The corrected shift-down vehicle speed MVd is calculated by multiplying by the corrected correction coefficient MV. Then, in the next step S12,
The corrected shift-down vehicle speed MVd is compared with the current vehicle speed V represented by the vehicle speed signal SV read in step S2, and it is determined whether downshift is performed or not depending on whether V ≦ MVd, and V ≦ If MVd, the shift stage of the automatic transmission 68 is switched to downshift in step S13, but if MVu <V, execution of step S1 and subsequent steps is repeated.

Here, when the correction correction coefficient MK is larger than 1.0, the correction shift-up vehicle speed MVu and the correction shift-down vehicle speed MVd move to the high vehicle speed side and are easily downshifted, while the correction correction is performed. When the coefficient MK is smaller than 1.0, the corrected shift-up vehicle speed MVu and the corrected shift-down vehicle speed MVd move to the low vehicle speed side and are easily upshifted. The correction correction coefficient MK is obtained, for example, according to the flow chart of FIG. 3, and this flow has substantially the same cycle time as that of the flow of FIG.
It is sequentially updated by being repeatedly executed at a time interval of about 2 msec. In FIG. 3, step S
21, S22, and S23 read the throttle valve opening signal STA, the engine speed signal SNE, and the intake air amount signal SQm, respectively, and in step S24, the throttle valve opening signal TA and the engine speed signal represented by the throttle valve opening signal STA. Based on the engine speed NE represented by SNE, the required intake air amount Qc is calculated from, for example, a predetermined data map or arithmetic expression as shown in FIG. Then, in the next step S25, the correction coefficient K1 is calculated by dividing the required intake air amount Qc by the actual intake air amount Qm represented by the intake air amount signal SQm. This corresponds to the idle speed control valve 3
8 or the variable valve timing mechanism 52 or other variable mechanism operating state, atmospheric pressure, etc.
, The actual intake air amount Qm is different, and appropriate shift control cannot be performed only with the shift map defined for the throttle valve opening TA and the vehicle speed V. Therefore, the throttle valve opening TA To correct the shift control by correcting the shift-up vehicle speed Vu and the shift-down vehicle speed Vd according to the ratio between the required intake air amount Qc obtained from the engine speed NE and the actual intake air amount Qm. Is.

On the other hand, due to a measurement error in the engine speed NE, the throttle valve opening TA, and the intake air amount Qm, or a calculation error in obtaining the required intake air amount Qc from the engine speed NE and the throttle valve opening TA. It is unavoidable that a certain amount of error is introduced into the required intake air amount Qc and the intake air amount Qm, and in particular in the region where the required intake air amount Qc and the intake air amount Qm are small, even if the error is small, the correction coefficient is small. K1 is greatly affected, and the shift control may be deteriorated if the correction is performed according to the correction coefficient K1. Therefore, in the present embodiment, in subsequent steps S26 and S27, the weighting of the correction coefficient K1 is changed according to the value of the intake air amount Qm, and the intake air amount Qm is changed.
In a region where there is a small amount of correction, a correction correction coefficient MK that reduces the correction amount by the correction coefficient K1 is obtained, and the correction up coefficient VK and the downshift vehicle speed Vd are calculated using the correction correction coefficient MK.
I am trying to correct. That is, step S26
Then, the correction coefficient KH is calculated according to the actual value of the intake air amount Qm from, for example, a data map or an arithmetic expression as shown in FIG. 8, and in step S27, the correction coefficient KH is used to calculate the following equation. According to (1), the correction correction coefficient MK is calculated. The correction coefficient KH is
1.0 if the intake air amount Qm is greater than or equal to a predetermined value
However, the correction correction coefficient MK is brought closer to the value KG in accordance with the value of the correction coefficient KH.

[0018]

## EQU1 ## MK = (K1-KG) × KH + KG (1)

The above-mentioned value KG is the control center value, that is, the average of the correction coefficient K1 when the variable mechanism such as the idle speed control valve 38 and the variable valve timing mechanism 52 is in a predetermined standard operating state, for example, when the air conditioner is OFF. The required intake air amount Qc basically coincides with the actual intake air amount Qm and becomes 1.0, but the calculation error of the required intake air amount Qc and the intake air amount by the air flow meter 16 Required intake air amount Qc due to Qm measurement error
Does not always match the actual intake air amount Qm,
It also changes due to changes over time in each part. For this reason, for example, the control center value K according to the flowchart of FIG.
G is obtained, and the difference (K1-KG) between the control center value KG and the correction coefficient K1 is multiplied by the correction coefficient KH to obtain the control center value K in the region where the intake air amount Qm is small.
The correction amount, that is, the difference | MK-KG | between the control center value KG and the correction correction coefficient MK is reduced by a rate corresponding to the correction coefficient KH with G as a reference.

The above-mentioned flow chart of FIG. 4 is repeatedly executed with substantially the same cycle time as the flow of FIG. 3, and the control center value KG is sequentially updated. In step S31 of FIG. 4, it is determined whether the driving state of the vehicle satisfies a predetermined learning condition. As the learning condition, the idle speed control valve 38
The variable condition such as the variable valve timing mechanism 52 and the variable valve timing mechanism 52 is in a predetermined standard operating state, and is in a steady state in which the change ΔTA of the throttle valve opening TA is substantially zero. If the condition is satisfied, the correction coefficient K1 calculated in step S25 is read in in step S32. At step S33, the moving average KGn of the latest constant number of correction coefficients K1 read at step S32 is calculated.
At 34, it is determined whether or not the moving average KGn satisfies a predetermined update condition, for example, the current control center value KG.
It is determined whether the difference | KG-KGn | between the moving average KGn and the moving average KGn is larger than a predetermined constant value. If the update condition is satisfied, the control center value KG is updated in step S35. In the update in step S35, the moving average KGn can be used as a new control center value KG as it is, but in order to suppress the frequent fluctuation of the control center value KG, for example, it is expressed by the following equation (2). It is desirable to change gradually. Even when the learning condition of step S31 is satisfied, the control center value KG varies depending on operating conditions such as the size of the throttle valve opening TA. It is desirable that the control center value KG is set and updated, and in the step S27, the control center value KG corresponding to the current operating condition is read to calculate the correction correction coefficient MK.

[0021]

(2) KG = KG + (KGn-KG) / 2 (2)

Then, the correction correction coefficient MV obtained as described above is multiplied by the shift-up vehicle speed Vu and the shift-down vehicle speed Vd to obtain the correction shift-up vehicle speed MVu and the correction shift-down vehicle speed MVd, and the correction shift-up is performed. The shift determination is made based on the vehicle speed MVu and the corrected shift-down vehicle speed MVd, but the correction coefficient KH is 1.0.
In a region where the intake air amount Qm is relatively large, in other words, in a region where the influence of the error of the intake air amount Qm or the required intake air amount Qc on the correction coefficient K1 is small, the correction coefficient K1 is set as the correction correction coefficient MK as it is, and the idle Appropriate shift control is performed regardless of the operating state of various variable mechanisms such as the rotation speed control valve 38 and the variable valve timing mechanism 52, or the atmospheric pressure change.

On the other hand, in the region where the intake air amount Qm is small, in other words, in the region where the error of the intake air amount Qm or the required intake air amount Qc has a large effect on the correction coefficient K1, the correction coefficient KH is made smaller than 1.0 and the correction is performed. Since the correction amount | MK-KG | by the correction coefficient MK is reduced according to the correction coefficient KH, the required intake air amount Qc and the intake air amount Q are obtained.
Deterioration of the shift control due to the error of m is favorably prevented.

Further, in this embodiment, since the correction amount | MK-KG | is set to be small with reference to the control center value KG, the calculation error of the required intake air amount Qc and the intake air amount Qm by the air flow meter 16 are made. The correction correction coefficient MK can always be corrected to an optimum value regardless of the measurement error of A, the change of each part with time, and the intake air amount Q.
In conjunction with changing the weighting of the correction coefficient K1 according to m, the required accuracy for calculating the required intake air amount Qc and measuring the intake air amount Qm by the air flow meter 16 is relaxed. In this case, since the control center value KG is calculated based on the correction coefficient K1, a more accurate control center value KG is calculated as compared with the case where the control center value KG is obtained using the modified correction coefficient MK. It

In the present embodiment, of the series of signal processing by the transmission control computer 34, the part that executes the steps of FIG. 2 corresponds to the shift control means, and the part that executes steps S6 and S11 is the part that executes steps S6 and S11. It corresponds to a correction means. In addition, step S21 in FIG.
The part that executes to S25 corresponds to the correction coefficient calculation means,
The part that executes steps S26 and S27 corresponds to the correction coefficient correction means, and the pre-stored shift maps of FIGS. 5 and 6 represent shift conditions.

Next, another embodiment of the present invention will be described.

In the embodiment shown in FIG. 9, the correction coefficient K2 is changed by modifying step S25 and subsequent steps in the flow chart of FIG.
In addition, the correction coefficient K2 is multiplied by the shift-up vehicle speed Vu or the shift-down vehicle speed Vd instead of the correction correction coefficient MK to obtain the corrected shift-up vehicle speed MVu or the corrected shift-down vehicle speed MVd.
Is to be asked. Step S41 of FIG.
Then, a difference Qa (= Qc-Qm) between the required intake air amount Qc and the actual intake air amount Qm is calculated, and in step S42, the difference Qa is equal to or greater than a predetermined lower limit value α (<0) and It is determined whether or not the upper limit value β (> 0) or less. Then, if α ≦ Qa ≦ β, the correction value X = Qa is set in step S43, if Qa <α, the correction value X = α is set in step S44, and if Qa> β, in step S45. The correction value X is set to β, and the correction coefficient K2 is calculated according to the following equation (3) in the next step S46. As shown in FIG. 10, the correction coefficient K2 is closer to 1.0 than the correction coefficient K1 regardless of the intake air amount Qm.
The correction amount is corrected to a small amount, but the correction amount | K1
-K2 | is larger in the case of FIG. 10 (a) where the intake air amount Qm is smaller than in the case of FIG. 10 (b) where the intake air amount Qm is large. In other words, in the region where the intake air amount Qm is small, the weighting of the correction coefficient K1 is smaller than in the region where the intake air amount Qm is large, and the correction amount by the correction coefficient K1 is substantially reduced. The same effect as can be obtained. The correction amount | K1-K2 | becomes smaller as the lower limit value α and the upper limit value β are closer to 0, and the correction amount | K1-K2 | becomes larger as the lower limit value α and the upper limit value β depart from 0. , Correction amount when intake air amount Qm is small | K1-
The lower limit value α and the upper limit value β thereof are set based on K2 |. In this embodiment, of the series of signal processing by the transmission control computer 34, the part that executes steps S41 to S45 corresponds to the correction coefficient correction means, and the part that executes steps S21 to S24 and step S46 is the correction coefficient. It corresponds to a calculation means.

[0028]

## EQU00003 ## K2 = Qc / (Qm + X) (3)

Although one embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be implemented in other modes.

For example, in the first embodiment, the shift-up vehicle speed Vu and the shift-down vehicle speed Vd are obtained from the shift map, and the vehicle speeds Vu and Vd are corrected by the correction correction coefficient MK. The actual vehicle speed V to be compared with Vu, Vd is divided by the correction correction coefficient MK for correction, or the actual throttle valve opening TA when the vehicle speed Vu, Vd is obtained from the shift map is multiplied by the correction correction coefficient MK. Correction, shifting the shift line of the shift map according to the correction correction coefficient MK, and selecting one corresponding to the correction correction coefficient MK from a plurality of types of shift maps prepared in advance. It is possible to employ means.
The same applies to the second embodiment.

Further, although the shift map of the above-described embodiment defines the vehicle speed V and the throttle valve opening TA as the shift parameters, when the throttle valve opening TA changes corresponding to the accelerator pedal operation amount, Instead of the throttle valve opening TA, the shift map can be set using the accelerator pedal operation amount, and the shift map can be set using other shift parameters. As for the engine speed NE and the throttle valve opening TA when the required intake air amount Qc is calculated, other parameters that substantially represent them can also be used.

In the first embodiment, the correction coefficient KH is set according to the value of the actual intake air amount Qm, but the correction coefficient KH is set according to the value of the required intake air amount Qc. It can also be set.

The data map of FIG. 8 in the first embodiment is an example, and may be appropriately changed, for example, when the intake air amount Qm is equal to or less than a predetermined constant value, the correction coefficient KH = 0. It is possible.

Further, in the first embodiment, the control center value KG
Although the correction correction coefficient MK is calculated with reference to, the calculation error of the required intake air amount Qc, the measurement error of the intake air amount Qm by the air flow meter 16, the change over time of each part, etc. can be ignored. The correction correction coefficient MK can be calculated by substituting 1.0 for the control center value KG.

The control center value KG is 1/2 of the difference (KGn-KG) from the newly obtained moving average KGn.
Although the amount of change is not necessarily 1/2, it may be 1/3, 2/3, or the like, and of course, it may be changed by a predetermined amount. It is also possible to change at a constant rate of change.

Further, in the second embodiment, the correction value X is added to the actual intake air amount Qm to calculate the correction coefficient K2, but a predetermined correction value is subtracted from the required intake air amount Qc. It is also possible to calculate the correction coefficient K2 according to another arithmetic expression such as calculation. As in the first embodiment, the correction coefficient K1 may be calculated in advance, and then the correction coefficient K1 may be corrected according to the value of the difference Qa.

Further, although the movable vane type air flow meter 16 is used as the intake air amount detecting means in the above-described embodiment, other air flow meters such as the Karman vortex type and the heat wire type can be adopted, and the atmospheric pressure change can of course be adopted. It is also possible to detect the intake air amount by measuring the intake pipe pressure at the expense of the correction for.

In the above embodiment, the idle speed control valve 38 and the variable valve timing mechanism 52 are used as the variable mechanism.
However, the present invention can be similarly applied to a shift control device for an automobile having another variable mechanism that affects the actual intake air amount.

Although the engine control computer 32 and the transmission control computer 34 are separately configured in the above embodiment, the engine 10 and the automatic transmission 68 may be controlled by a single computer.

Although not illustrated one by one, the present invention can be carried out in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a configuration of an automatic transmission, an engine, and the like including a shift control device that is an embodiment of the present invention.

FIG. 2 is a flow chart for explaining an operation at the time of switching the shift speed of the automatic transmission in the embodiment of FIG.

3 is a flowchart for obtaining a correction correction coefficient MK used in steps S6 and S11 of FIG.

FIG. 4 is a flowchart for obtaining a control center value KG used in step S27 of FIG.

FIG. 5 is an example of an upshift side shift map used when executing the flowchart of FIG.

FIG. 6 is an example of a downshift side shift map used in executing the flowchart of FIG.

7 is an example of a data map for obtaining a required intake air amount Qc from an engine speed NE and a throttle valve opening TA used in step S24 of FIG.

8 is an example of a data map for obtaining a correction coefficient KH from the intake air amount Qm used in step S26 of FIG.

9 is a diagram showing a main part of another embodiment of the present invention, and is a flowchart for obtaining a correction coefficient K2 used in place of the modified correction coefficient MK in the flowchart of FIG.

FIG. 10 is a diagram illustrating that the correction amount of the correction coefficient K2 differs depending on the intake air amount Qm in the embodiment of FIG.

FIG. 11 is a diagram corresponding to the claims of the present invention.

[Explanation of symbols]

 10: engine 16: air flow meter (intake air amount detecting means) 20: throttle valve 34: transmission control computer 36: throttle position sensor 68: automatic transmission 72: vehicle speed sensor V: vehicle speed (shift parameter) TA: throttle valve open Degree (shift parameter) NE: engine speed Qc: required intake air amount Qm: actual intake air amount K1, K2: correction coefficient MK: correction correction coefficient Steps S6, S11: correction means Steps S21 to S25: correction coefficient calculation means Steps S26, S27: Correction coefficient correction means Steps S41-S45: Correction coefficient correction means Steps S21-S24, S46: Correction coefficient calculation means

Claims (1)

Claim: What is claimed is: 1. A shift control means for automatically switching a shift stage of an automatic transmission according to an actual shift parameter value in accordance with a predetermined shift condition, an engine speed and a throttle valve. Correction coefficient calculating means for calculating the required intake air amount based on the opening degree, and for calculating a ratio between the actual intake air amount detected by the intake air amount detecting means and the required intake air amount as a correction coefficient; A shift control device for an automatic transmission, comprising: a correction unit that corrects either the shift condition or the value of an actual shift parameter according to a coefficient, in a region where the required intake air amount or the actual intake air amount is small. The present invention is characterized in that correction coefficient correction means for correcting the correction coefficient is provided so that the correction amount by the correction coefficient becomes substantially smaller than that in a large area. Shift control device of the transmission.