JP3505874B2 - Control device for automatic transmission - Google Patents

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 that performs shift control based on a preset shift map, and particularly when the vehicle is traveling on a downhill road, the shift map is set to a low shift. The present invention relates to a control device for an automatic transmission that switches to a shift map for downhill traveling with a wide step region and executes shift control based on the downhill traveling map.

[0002]

2. Description of the Related Art Generally, a control device for an automatic transmission mounted on a vehicle determines a shift speed by applying these two measured values to a shift map which is set in advance with vehicle speed and throttle opening as parameters. It is designed to shift gears.

In this case, the shift map for normal traveling, in which the shift change is appropriately performed on a flat road, and the shift line for the shift speed is set to a relatively high vehicle speed side as compared with the map for normal traveling, and the shift line is set low. A shift map for downhill traveling having a wide shift range is provided, and when the road gradient is detected and it is determined from the detection result that the vehicle is traveling on a downhill road, the shift map is set to the above-mentioned normal map. There is a method in which a larger engine brake suitable for traveling on a downhill road is obtained by switching from the traveling map to the downhill traveling map and performing shift control based on the downhill traveling map. It is also known that only one type of map is provided and the map itself is modified so that the low speed range is widened.

In any case, when the vehicle is traveling on a downhill road, the shift map is changed to a downhill travel map, whereby the shift stage becomes a low shift stage in which a larger engine brake is obtained. Although it may be switched, some drivers may feel that deceleration is not necessary and engine braking is not necessary.If the shift control based on the downhill traveling map is performed at such a time, the driver feels uncomfortable. Will be given.

Therefore, in Japanese Patent Laid-Open No. 5-71626, even when the vehicle is traveling on a downhill road, when the throttle opening (engine load) becomes equal to or larger than a predetermined opening, a gear shift is performed. It is disclosed that the map is returned from the downhill traveling map to the normal traveling map. In other words, the fact that the throttle opening exceeds the predetermined opening means that the driver does not need engine braking and wants to accelerate by depressing the accelerator pedal. The shift control based on (1) is switched to the shift control based on the normal travel map, whereby the driver's will is taken into consideration and the driver does not feel uncomfortable in shifting, and the drive feeling can be improved.

[0006]

However, in the above-mentioned prior art, the shift map is switched between the downhill traveling map and the normal traveling map depending on the magnitude relationship between the throttle opening and the predetermined opening. If a person frequently operates the accelerator pedal or if the throttle opening slightly changes in the vicinity of a predetermined opening, a problem of control hunting occurs.

Further, if the throttle opening is equal to or larger than a predetermined opening, it is impossible to judge whether the driver really wants the engine braking and wants to accelerate,
For example, after the shift stage was switched to the low shift stage by the shift control based on the downhill traveling map, the vehicle speed became considerably low due to the effect of the engine brake, so that the driver tried to correct the vehicle speed a little. Even if the accelerator pedal is slightly depressed for the purpose, the shift map is switched to the normal travel map, which again gives the driver a feeling of strangeness in the shift.

Therefore, the present invention changes the shift map from the normal travel map to the downhill travel map when traveling downhill, and when the driver desires acceleration, the normal downhill traveling map is used. In a control device for an automatic transmission that switches to a travel map, it is an object to more accurately reflect the driver's intention and realize a good drive feeling without a feeling of discomfort.

[0009]

That is, the invention according to claim 1 of the present invention (hereinafter referred to as "first invention").
Is equipped with a shift map for normal running and a shift map for downhill running in which the low shift range is wider than the normal running map, and the road surface gradient for detecting the road gradient is provided.
Comprising distribution detection means, when it is determined that the vehicle from the detection result of said detecting means is descending traveling slope switches the shift map from the normal traveling map to downhill travel map,該降slope traveling A control device for an automatic transmission that executes shift control based on a map, in which the accelerator pedal is depressed.
Idle detection means for detecting whether or not the user
Of the accelerator pedal depression detected by the
Storage means for storing the previous vehicle speed, and the road surface gradient detection means
It is determined that the vehicle is traveling downhill from the detection result of
The idle detection means, the accelerator is
The storage means for the vehicle speed after the depression of the pedal is detected
In when the amount of increase in the vehicle speed relative to vehicle speed stored exceeds a predetermined increase amount, and the map switching means for switching from the shift control based on the downhill travel map to shift control based on the normal running map is provided, And the above specified increase
Is the slope of the downhill road detected by the road slope detecting means.
When it is large, it is set larger than when it is small.
Lower when the vehicle speed is high just before the accelerator pedal is depressed
It is characterized by being set larger than when .

According to the first aspect of the invention, the vehicle travels downhill.
If you are determined to be traveling, press the accelerator pedal.
Depressing the accelerator pedal at the vehicle speed after the intrusion is detected
Only when the increase amount of the vehicle speed with respect to the immediately preceding vehicle speed exceeds a predetermined increase amount , the shift map is switched from the downhill traveling map to the normal traveling map, and the shift control based on the normal traveling map is executed. .

That is, the depression of the accelerator pedal is detected.
The vehicle speed immediately after the accelerator pedal is depressed
The increase in the vehicle speed exceeds a predetermined increase amount for the
Since the driver Ru results der of continued depression of the accelerator pedal until increases so much speed, in such a case, the driver is truly required engine braking, it is determined that wants to accelerate, shift The map is switched from the downhill traveling map to the normal traveling map, and the shift control based on the normal traveling map is performed.

As a result, the driver's will is reflected more accurately, and a good drive feeling without discomfort is realized.

[0013]

[0014] In the first aspect of the invention, where the vehicle speed
The constant increase amount is detected by the downhill angle , that is, the road surface slope detecting means.
Since the degree of the issued downhill gradient is set larger than when it is small when the large, running a downhill steep necessary engine braking to a great extent the vehicle speed is high kuna Rana <br /> As long as the shift map can not be switched from the downhill travel map to the normal travel map, traveling with engine braking will be realized as much as possible, and conversely, while traveling on a gentle downhill, change speed map also not become the vehicle speed is high is switched to the normal running map from downhill travel map, as soon as possible engine brake is released, good drive feeling that matches the intention of the driver is maintained It will be.

[0015]

In addition, according to the first aspect of the present invention, the predetermined increase amount is set to be higher when the vehicle speed is higher immediately before the accelerator pedal is depressed than when the vehicle speed is low. It becomes difficult to switch from the operation map to the normal travel map. In other words, when the map for downhill traveling is switched to the map for normal traveling while the vehicle speed is high, the shift map is then switched again from the map for normal traveling to the map for downhill traveling, and the gear position is improved. When switching to a low shift stage where a large engine brake works, the shift shock becomes large and gives an occupant an uncomfortable feeling, so that such a problem can be eliminated.

[0017] The invention of claim 2 (hereinafter "second
2 invention ”. ), In the first invention, the depression amount detecting means for detecting the depression amount of the accelerator pedal by the driver
The map switching means is equipped with an idle detection means.
Means for storing vehicle speed after detection of depression of cell pedal
The increase in vehicle speed with respect to the vehicle speed stored in
Even if the load is not exceeded, the idle detection means will
When the time from when the depression of the pedal is detected for a predetermined
When exceeded during the switching from the speed change control based on the downhill travel map to shift control based on the normal traveling map,
Moreover, the predetermined time is detected by the road surface slope detecting means.
When the slope of the descending slope is large, it is longer than when it is small
Accelerator pedal that has been set to
When the pedal stroke is small, it is set longer than when it is large.
It is characterized by being set.

According to the second aspect of the present invention, the idle detection hand
Of vehicle speed after the accelerator pedal depression is detected
Increase in vehicle speed with respect to vehicle speed stored in the storage means
Even if the amount does not exceed the predetermined increment, the idle detection
When the time from when the accelerator pedal depression is detected at a gear exceeds a predetermined time , the shift map is switched from the downhill traveling map to the normal traveling map, and the normal traveling map is used. The shift control is executed.

[0019] That is, the fact that the OPERATION user continues depressing the accelerator pedal a predetermined time or more, it can be determined that the driver wishes to clearly accelerated, in such a case, the map for downhill traveling shift map Is switched to the normal travel map, and the shift control based on the normal travel map is performed.

[0020] Thus, luck rolling's will is more accurately reflect, there is no discomfort, a good drive feeling can be realized.

[0021]

Further, in this second aspect of the invention, inter <br/> when the predetermined is descending Bankaku, i.e. detected by the road gradient detecting means
When the grade of the downhill road is large, it is set longer than when it is small.Therefore, when traveling on a steep slope that requires engine braking, the shift map runs downhill unless you continue to depress the accelerator pedal for too long. The map can not be switched from the driving map to the normal driving map, and driving with engine braking will be realized as much as possible, and conversely, when driving on a downhill slope with a gentle slope, it is possible to shift map without continuously pressing the accelerator pedal for too long. Is switched from the downhill travel map to the normal travel map, the engine brake is released early, and a good drive feeling that matches the driver's intention is maintained.

[0023]

In addition, according to the second aspect of the present invention, the predetermined time is set longer when the accelerator pedal depression amount is smaller than when the accelerator pedal depression amount is large. If the driver does not step hard, it is difficult to switch from the downhill traveling map to the normal traveling map. Therefore, the problem that the shift map is switched to the normal travel map and the driver feels uncomfortable when the driver slightly depresses the accelerator pedal for the purpose of slightly increasing the vehicle speed is solved. It will be.

[0025]

Further, according to the second invention, when determining whether or not to return to the normal running map for the shift map from the downhill traveling map based <br/> the car speed, the accelerator pedal Since the depression time can be used as a backup for the determination, the shift map is switched at an appropriate timing.

The invention according to claim 3 (hereinafter “
3 invention ”. ), The first invention or Contact <br/> to have a second shot bright, even if the vehicle from the detection result of the road surface gradient is judged to be descending traveling slope, foot brake is depressed When it is not, the shift map is not switched from the normal travel map to the downhill travel map.

In the third aspect of the invention, since the shift map is changed to the downhill travel map only when the footbrake is depressed during downhill travel, the shift mode is switched to a lower shift stage in which a larger engine brake is effective. In addition to maintaining the running stability at this time, the driver's clear deceleration of depressing the foot brake is taken into consideration to realize control without a sense of discomfort.

[0029]

[0030]

[0031]

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, in the vehicle in this embodiment, the left and right front wheels 1 and 2 are driven wheels, and the left and right rear wheels 3 and 3.
4 is a drive wheel, and the output torque of the engine 5 is transmitted from the automatic transmission 6 to the left and right rear wheels 3, 4 via the propeller shaft 7, the differential device 8 and the left and right drive shafts 9, 10. Has become.

Further, the wheels 1 to 4 are provided with discs 11 ... 11 that rotate integrally with the wheels 1 to 4, and calipers 12 ... 12 that brake the rotation of the discs 11 ... 11 by receiving a braking pressure. 12 is provided, braking pressure is supplied to the calipers 12, ... 12 by depressing the brake pedal 13 to brake the rotation of each of the wheels 1 to 4, and a throttle valve 14 is provided in the intake system of the engine 5. When the accelerator pedal 15 is depressed, the opening of the throttle valve 14 is changed, the intake air amount is variably controlled, and the engine output is adjusted.

In this vehicle, a vehicle speed sensor 16 for detecting the vehicle speed, a throttle sensor 17 for detecting the opening of the throttle valve 14, an idle switch 18 which is turned on when the throttle valve 14 is fully closed, And a brake switch 19 that is turned on when the brake pedal 13 is depressed, and a control unit 21 that outputs a shift signal to a shift unit 20 of the automatic transmission 6 based on signals input from these switches. It is equipped.

The control unit 21 always executes shift control according to the flow chart shown in FIG. 2 while traveling. That is, in step S1, the map flag Fmap
Looking at the state (described later), when it is 0, the routine proceeds to step S2, and shift control is executed using the normal travel shift map illustrated in FIG. 3, while when it is 1, step S2 is performed.
3, the shift control is executed using the downhill traveling shift map illustrated in FIG.

As shown in each of these maps, each shift speed is set in advance using the vehicle speed and the throttle opening as parameters, and the vehicle speed detected by the vehicle speed sensor 16 and the throttle sensor 17 are detected. By applying the throttle opening and the corresponding throttle opening, the corresponding shift speed is determined as the shift speed most suitable for the operating condition.

In this case, in the normal traveling map shown in FIG. 3, each shift line is set so that a smooth shift can be realized exclusively on a flat road, whereas in the downhill traveling map shown in FIG. Then, 2-3 shift line, 3-4 shift line,
The 4-3 shift line and the 3-2 shift line are provided on the high vehicle speed side to expand the low shift range, and even when the vehicle speed and the throttle opening are the same, when the above normal travel map is used, In comparison, it is set so that the tendency to run at a lower shift speed with a larger engine brake is increased.

Which of these two types of maps is used to execute the shift control is determined by the state of the map flag Fmap, and the control unit 21 determines the state of this map flag Fmap as shown in FIG. , According to the flowchart shown in FIG.

This map flag determination control is repeatedly executed in a predetermined control cycle (for example, 20 ms) separately from the above-mentioned shift control, and the map flag Fmap is read out at the end of each cycle or at a predetermined timing to perform the shift control. It is being used.

First, the outline of this control will be described.
First, it is determined whether the vehicle is traveling on a flat road or a downhill road, and if the vehicle is traveling on a flat road, the map flag Fmap is set to 0 so that the normal traveling map is used. When the vehicle is traveling on a downhill road, the map flag Fmap is set to 1 and the downhill traveling map is used only when the brake pedal 13 is depressed and the vehicle is decelerated greatly. Even if the map flag Fmap is 1, the accelerator pedal 15
When the vehicle is stepped on and the vehicle speed from the time of stepping on has increased by a considerable amount or the stepped state has continued for a considerable time, the map flag Fmap is reset to 0 and the shift map is changed from the downhill traveling map to the normal traveling map. It is configured to be switched to. Hereinafter, description will be made sequentially.

First, after reading various signals in step S11, a gradient value g is calculated (step S12). This gradient value g is calculated according to the grade of the road surface on which the vehicle is traveling, and is 0 on a flat road, a negative value on a downhill road, and a smaller value when the downhill road angle is large than when it is small. Becomes

The following steps S13 to S16 are a routine for determining whether the vehicle is traveling on a flat road or a downhill road. First, the calculated gradient value g is set to a predetermined value. It is determined whether it is less than the first gradient predetermined value K1 (step S13). The first predetermined value K1 is set to a relatively small negative value. That is, it is determined whether the vehicle is traveling on a steep downhill road.
If YES, the process proceeds to step S14 to set the gradient flag Fg to 1, and if NO, the process proceeds to step S15 to further determine whether or not the gradient value g is equal to or more than a predetermined second gradient predetermined value K2. This second predetermined value K2 is the first predetermined value K
It is set to a negative value larger than 1 and close to 0. That is, it is determined whether the vehicle is traveling on a flat road with almost no slope. The gradient value g is the second predetermined value K
If it is 2 or more, the routine proceeds to step S16, where the gradient flag Fg
Is reset to 0, while if NO, that is, if the gradient value g is between the first predetermined value K1 and the second predetermined value K2, the process directly proceeds to the next step S17.

As a result, a hysteresis is provided between the predetermined values K1 and K2, and when it is determined that the vehicle is traveling on a steep downhill road, the gradient flag Fg is set to 1 (step (S13, S14), or if it is determined that the vehicle is traveling on a flat road, it is reset to 0 (steps S15, S16), but if the grade of the road surface is in the middle of these, the flag Fg is updated. Since it is not done and the previous state is maintained (steps S15, S1
7) The switching hunting of the gradient flag Fg is prevented.

The following steps S17 to S20 are a routine for preparing to return the map flag Fmap from 1 to 0. First, in step S17, it is determined whether or not the idle switch 18 is ON. That is, it is determined whether or not the accelerator pedal 15 is depressed. If YES, then proceed to step S18,
The vehicle speed V read in step S11 is stored as the vehicle speed Vi during idling. This idle vehicle speed Vi is continuously updated while the accelerator pedal 15 is not depressed, and when the accelerator pedal 15 is depressed,
As will be described later, the process proceeds from step S17 to step S20, and the updating of the idle vehicle speed Vi is stopped. Therefore, the idle vehicle speed Vi remains as the vehicle speed immediately before the accelerator pedal 15 is depressed, that is, the vehicle speed when the accelerator pedal 15 is depressed.

On the other hand, if NO in step S17, that is, if the accelerator pedal 15 is depressed, the process proceeds to step S20 to count the timer. This timer continues to be counted while the accelerator pedal 15 is being depressed, and when the accelerator pedal 15 is not depressed, it is cleared in step S19 following step S18. Therefore, this timer counts the time t from the depression of the accelerator pedal 15.

Next, steps S21 to S24, which are carried out after step S19 when the accelerator pedal 15 is not depressed, will be described. This is a routine for determining whether or not the map flag Fmap is set to 1. First, in step S21, it is determined whether or not the brake switch 19 is ON. That is, it is determined whether or not the brake pedal 13 is depressed. And Y
In the case of ES, the process proceeds to step S22 and it is determined whether or not the deceleration is large. That is, it is determined whether or not a large deceleration has occurred due to the depression of the brake pedal 13. If YES, the state of the gradient flag Fg described above is checked in step S23, and if this is 1, that is, if the vehicle is traveling on a downhill road, step S24.
Then, the map flag Fmap is set to 1.

However, these steps S21, S
22 or S23, the brake pedal 13
Is not depressed, the deceleration is not large, or the gradient flag Fg is 0, the next step S2 is performed without passing through step S24 in which the map flag Fmap is set to 1.
Go to 5. That is, the map flag Fmap is set to 1 only when the vehicle is traveling on a downhill road and the brake pedal 13 is stepped on and greatly decelerated. When the accelerator pedal 15 is depressed, the process proceeds from step S20 to step S25 without executing these steps S21 to S24 for determining whether to set the map flag Fmap to 1.

Next steps S25 and S26
Is a routine for setting a predetermined value for determination for returning the map flag Fmap from 1 to 0.

First, the predetermined value F set in step S25
v is a value obtained by subtracting the vehicle speed Vi when the accelerator pedal 15 is depressed from the vehicle speed V in the subsequent step S30, that is, for determining the amount of increase in the vehicle speed since the accelerator pedal 15 is depressed. Is a predetermined value (hereinafter, referred to as "vehicle speed predetermined value") used for.

This predetermined vehicle speed value Fv is, as conceptually shown in FIG. 7, a vehicle speed Vi when the accelerator pedal 15 is depressed.
It is set by applying these actual values to a map of the value f1 that is a function for both the gradient value g and the gradient value g to determine the corresponding value f1, and setting this as the predetermined value Fv. In this case, the function value f1 is larger when the vehicle speed Vi when the accelerator pedal 15 is depressed as shown in FIG. 8 is higher than when it is low, and when the gradient value g is small as shown in FIG. Is set to be larger than when it is larger. Therefore, the accelerator pedal 15
The higher the vehicle speed Vi when the vehicle is stepping on or the steeper the gradient, the more difficult it is to determine YES in step S30 unless the amount of increase in vehicle speed is relatively large.
The function value f1 changes linearly as shown in the figure, but may change stepwise.

On the other hand, the predetermined value F set in step S26
t is a predetermined value (hereinafter, referred to as “time predetermined value”) used to determine the length of the time t from the depression of the accelerator pedal 15 in step S31 described later.

As shown conceptually in FIG. 10, this predetermined time value Ft is obtained by fitting these actual values to a map of the value f2 which is a function of both the throttle opening TVO and the gradient value g. The corresponding value f2 is calculated and set as a predetermined value Ft. In this case, the function value f2 is calculated by the throttle opening T as shown in FIG.
It is set so that when VO is small, it is larger than when it is large, and as shown in FIG. 12, it is larger when the gradient value g is larger than when it is large. Therefore, if the throttle opening TVO is smaller or the gradient is steeper, the time t from the time when the accelerator pedal 15 is depressed is not relatively long, and YE in step S31.
It becomes difficult to be judged as S. Even in this case, the function value f2 may change linearly as shown in the example, or may change stepwise.

The following steps S27 to S31 are routines for determining whether the map flag Fmap is set to 0 and whether it is returned from 1 to 0.

First, in step S27, the state of the gradient flag Fg is checked. If it is 0, that is, if the vehicle is traveling on a flat road, the process proceeds to step S28 and the map flag Fmap.
After making 0, it returns.

When the vehicle is traveling on a downhill road, the process proceeds to step S29, and the idle switch 18 is turned off.
When it is YES, that is, when the accelerator pedal 15 is not depressed, the routine directly returns, while when NO, that is, when the accelerator pedal 15 is depressed, the routine proceeds to step S30. The above-mentioned increase in vehicle speed is determined. And when YES,
That is, when the increase amount of the vehicle speed from the depression of the accelerator pedal 15 is larger than the vehicle speed predetermined value Fv set in step S25, the process proceeds to step S28 to set the map flag Fmap to 0 and then returns.

Furthermore, if NO in step S30, the flow advances to step S31 to determine the length of time t described above. When YES, that is, the accelerator pedal 15
When the time t from the time when is depressed is larger than the time predetermined value Ft set in the above step S26, the step S
The routine proceeds to 28, sets the map flag Fmap to 0, and then returns. That is, even if the increase amount of the vehicle speed does not exceed the vehicle speed predetermined value Fv, if the depression time t of the accelerator pedal 15 exceeds the time predetermined value Ft, the map flag Fm.
ap is set to 0, and the depression time t of the accelerator pedal 15 is used as a backup for control.

According to the map flag determination control described above, the map flag Fmap changes as follows based on the running state of the vehicle.

First, since the gradient flag Fg is set to 0 in step S16 while the vehicle is traveling on a flat road, steps S27 to S28 are executed regardless of the operating condition of the brake pedal 13 or the accelerator pedal 15 by the driver. The map flag Fmap is determined to be 0 via this. As a result, the shift control based on the normal traveling map is performed, and a smooth shift suitable for traveling on a flat road is realized.

Next, a case where the vehicle enters a downhill road from a flat road and the gradient flag Fg is switched to 1 in step S14 will be described. First, when the driver is still operating the accelerator pedal 15 with the intention of accelerating, step S
After reaching from step 17 to step S25 through step S20, the process further proceeds from step S29 to step S30 or S31. However,
Even if YES is determined in these steps S30 and S31 and the process proceeds to step S28, or if NO is determined and the process returns as it is, the map flag Fmap remains unchanged at 0.

When the operation of the accelerator pedal 15 is stopped but the brake pedal 13 is not depressed, the steps S17 to S18 are followed by the step S18.
21, the process proceeds from step S25 to step S27, and then the process returns from step S29. Therefore, the map flag Fmap is not changed and remains 0.

However, when the driver depresses the brake pedal 13, the process goes from step S17 to step S21 to step S22, and only when a large deceleration occurs, the process proceeds to step S24 and the map flag Fmap is set to 1. After being changed, steps S25 to S
Go to 29 and return. As a result, the shift map is switched from the normal traveling map to the downhill traveling map, the shift control based on the downhill traveling map is performed, and a larger engine brake suitable for traveling downhill is obtained.

Thus, even if the gradient flag Fg is switched to 1, the map flag Fmap is changed to 1 after confirming that the brake pedal 13 is being depressed and that the vehicle is decelerating significantly. The running stability at the time of switching to a low shift stage where a larger engine brake is effective is maintained, and the driver's intention to decelerate is taken into consideration.

Then, the vehicle returns from the downhill road to the flat road,
When the gradient flag Fg is switched to 0 in step S16, the map flag Fmap is changed from 1 to 0 in step S28. Therefore, the shift map is again switched from the downhill travel map to the normal travel map, The shift control based on the travel map is performed, and the shift suitable for traveling on a flat road is realized.

Further, according to this control, even when the vehicle is traveling downhill, the map flag Fmap is changed from 1 to 0 in the following cases.
Is changed to. That is, after the accelerator pedal 15 is depressed to go from steps S17 to S20 to steps S25 to S27, the process further proceeds from the next step S29 to step S30 or S31, and YES is determined in these steps S30 and S31. That is the case.

At this time, the determination of YES in step S30 is made when the amount of increase in the vehicle speed after the accelerator pedal 15 is depressed becomes larger than the predetermined vehicle speed value Fv, as described above. That is, the fact that the increase amount exceeds the vehicle speed predetermined value Fv is a result of the driver continuing to depress the accelerator pedal 15 until the vehicle speed increases so much. Therefore, in such a case, the driver obviously applies the engine brake. It is unnecessary to determine that acceleration is desired, and the use of the downhill traveling map is stopped and the shift control is performed on the normal traveling map. As a result, the driver's will is reflected more accurately, and a good drive feeling without discomfort is realized.

Further, as described above, the determination of YES in step S31 is made when the time t from when the accelerator pedal 15 is depressed becomes larger than the predetermined time value Ft. That is, if the time t exceeds the predetermined time value Ft, it means that the driver is too long.
Since it is the result of continuing to step 5, even in such a case, it should be judged that the driver clearly wants to accelerate, and again, the use of the downhill traveling map is stopped and the normal traveling map is used. The shift control is performed. However, it is preferable from the viewpoint of control reliability that the map flag Fmap is changed from 1 to 0 when the vehicle speed actually increases by a considerable amount. Therefore, the determination in step S31 is NO in step S30. Run as backup.

The predetermined vehicle speed Fv is set higher when the vehicle speed Vi when the accelerator pedal 15 is depressed is higher than when the vehicle speed Vi is low, and the map flag Fmap is 0.
It is difficult to change to. Therefore, the problem of a large shift shock that occurs when the map flag Fmap is set to 1 again to switch to the low shift stage in a state where the vehicle speed is high is prevented.

The predetermined vehicle speed Fv is set to be larger when the gradient value g is smaller than when the gradient value g is large, so that the map flag Fmap is also unlikely to be changed to zero. Therefore, the map flag Fmap is not changed to 0 while the vehicle is traveling on a steep downhill slope where engine braking is required, so that the engine braking is performed as much as possible, and vice versa. The map flag Fmap is changed to 0 even if the vehicle speed is not so high while driving on a gentle downhill, the engine brake is released early, and a good drive feeling that matches the driver's intention is maintained. Will be.

On the other hand, the predetermined time value Ft is set to be larger when the throttle opening TVO is smaller than when the throttle opening TVO is large, so that the map flag Fmap is hard to be changed to 0. Therefore, when the driver does not depress the accelerator pedal 15 so strongly, the map flag Fm
When ap is not changed to 0 and the driver slightly depresses the accelerator pedal 15 for the purpose of correcting the vehicle speed slightly, the shift map is returned to the normal traveling map, giving a feeling of strangeness. Will be eliminated.

Further, the predetermined time value Ft is set to be larger when the gradient value g is smaller than when it is large, so that the map flag Fmap is also unlikely to be changed to 0. Therefore, while traveling on a steep downhill slope that requires engine braking, the accelerator pedal 1 is too long.
The map flag Fmap will not be changed to 0 unless the vehicle continues to depress 5, and the engine braking will be realized as much as possible. On the contrary, the accelerator pedal 15 will be depressed so long while traveling on a downhill slope. Even if it is not continued, the map flag Fmap is changed to 0, the engine brake is released early, and a good drive feeling that matches the driver's intention is maintained.

As described above, the throttle sensor 17 is used as a means for detecting the amount of depression of the accelerator pedal 15 by the driver. However, in addition to this, the accelerator opening for directly detecting the stroke (depression amount) of the accelerator pedal 15 is used. Detection means,
It is also possible to use an accelerator pedal force detecting means or the like which indirectly detects the stepping amount from the stress acting on the accelerator pedal 15.

[0073]

As described above, in the control device for an automatic transmission according to the present invention, the driver's intention to accelerate can be determined more appropriately based on the operation state of the accelerator pedal.
Since the shift map is switched and the shift control is executed according to the determination result, it is possible to realize a good drive feeling without causing the driver to feel uncomfortable.

[Brief description of drawings]

FIG. 1 is a control system diagram of a vehicle in an embodiment of the present invention.

FIG. 2 is a flowchart of shift control in the vehicle.

FIG. 3 is a shift map diagram for normal traveling used in the shift control.

FIG. 4 is a shift map diagram for downhill traveling used in the shift control.

FIG. 5 is a flowchart of control for determining the state of a map flag.

FIG. 6 is a flowchart diagram of control for determining the state of the map flag.

FIG. 7 is a conceptual diagram showing a tendency of a predetermined value used in the determination control.

FIG. 8 is a conceptual diagram showing a tendency of a predetermined value used in the determination control.

FIG. 9 is a conceptual diagram showing a tendency of a predetermined value used in the determination control.

FIG. 10 is a conceptual diagram showing a tendency of a predetermined value used in the determination control.

FIG. 11 is a conceptual diagram showing a tendency of a predetermined value used in the determination control.

FIG. 12 is a conceptual diagram showing a tendency of a predetermined value used in the determination control.

[Explanation of symbols]

5 engine 6 automatic transmission 13 Brake pedal 14 Throttle valve 16 vehicle speed sensor 17 Throttle sensor 18 Idle switch 19 Brake switch 21 Control unit

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuro Takaba No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Hidetoshi Nobemoto No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Matsu (56) References JP-A-3-24362 (JP, A) JP-A-3-92667 (JP, A) JP-A-4-327059 (JP, A) JP-A-5-71625 (JP , A) JP 62-122834 (JP, A) JP 6-241304 (JP, A) JP 5-71626 (JP, A) JP 61-79056 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (3)

(57) [Claims] 1. A shift map for normal traveling and a shift map for downhill traveling in which a low speed range is wider than that of the normal traveling map are provided, and a road surface gradient is detected.
Includes a road surface gradient detecting means, when it is determined that the vehicle from the detection result of said detecting means is descending traveling slope is that,
A control device for an automatic transmission, which switches a shift map from a normal travel map to a downhill travel map and executes shift control based on the downhill travel map, comprising an accelerator pedal
Idle detection means for detecting whether or not the pedal is depressed,
Accelerator pedal depression detected by the idle detection means
Storage means for storing the vehicle speed immediately before
If the vehicle is traveling downhill from the detection result of the detection means
If determined, the idle detection means
The vehicle speed above after the accelerator pedal depression is detected
When the increment of the vehicle speed relative to vehicle speed stored in the storage means exceeds a <br/> predetermined increment, map switching from speed control based on the downhill travel map to shift control based on the normal traveling map switching Means and the above-mentioned predetermined
The amount of increase in the
Larger gradients set larger than smaller gradients
When the vehicle speed is high immediately before the accelerator pedal is depressed,
A control device for an automatic transmission, which is set to be larger than when it is low . 2. The amount of depression of the accelerator pedal of the driver is detected.
A stepping amount detecting means for
Idle detection means detects depression of the accelerator pedal
Vehicle for the vehicle speed stored in the vehicle speed storage means after
Even if the speed increase amount does not exceed the predetermined increase amount,
When the accelerator pedal depression is detected by the
When the time from has exceeded the specified time,
Map-based shift control based on normal driving map
Switch to gear change control and keep the road surface
If the slope of the downhill detected by the distribution detecting means is large
Is set longer than when the
Larger when the released amount of the accelerator pedal is small
The control device for an automatic transmission according to claim 1, wherein the control device is set to be longer than a threshold time . 3. The vehicle is detected from the detection result of the road surface slope detecting means.
Even if it is determined that you are driving downhill,
When the brake is not depressed, the shift map
Switch from normal driving map to downhill driving map
Control system for an automatic transmission according to claim 1 or claim 2, characterized in that there is no.