JP3394082B2 - Shift control device for automatic transmission for vehicle - Google Patents

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 for a vehicle.

[0002]

2. Description of the Related Art Generally, an automatic transmission for a vehicle is adapted to automatically shift gears based on a preset shift pattern according to a running state of the vehicle. That is, a shift pattern for setting a shift stage according to the vehicle speed and the engine load (for example, throttle opening) is stored in the storage means of the control unit, and the shift is controlled according to this shift pattern.

It should be noted that this shift pattern is set such that, as long as the vehicle speed is the same, the smaller the engine load, the higher the shift up.

[0004]

However, in such a conventional shift control device, when the vehicle is traveling down a slope, a shift up occurs conversely in response to a deceleration request of a driver whose throttle opening is fully closed. As a result, there is a problem that sufficient engine braking cannot be obtained in response to a deceleration request.

From the above, for example, JP-A-4-
In Japanese Patent No. 60257, there is proposed one in which the magnitude of the negative torque transmitted from the drive wheel side to the engine side is detected by a torque sensor, and shift control is performed based on the detected magnitude. Further, in Japanese Patent Laid-Open No. 4-4351, a torque generated by an engine is calculated from a throttle opening and an engine speed, and a running resistance is calculated from the generated torque, a vehicle acceleration, and a vehicle weight. There has been proposed one that performs shift control based on the above.

Further, the applicant of the present application has proposed a method of performing gear shift control based on the current gear stage, vehicle speed, and gradient resistance when traveling downhill (Japanese Patent Application No. 5-272698).
issue). However, even if the shift control is performed according to the downhill shift pattern that is different from the shift pattern used during normal running when driving downhill as described above, the shift line at that time is fixed. It didn't always match.

That is, the driver may feel that the deceleration is too strong, or that the deceleration is too weak.
This does not always match the driver's preference, and therefore the driver operates from the D range (drive range) to another forward drive range (2 range or 1 range) or depresses the brake pedal. . The present invention is this
In view of such circumstances, it is an object of the present invention not only to optimize the control, but also to reflect the driver's preference when performing the shift control when traveling downhill in the D range .

[0008]

Therefore, according to the present invention, as shown in FIG. 1, when the vehicle is traveling downhill in the D range, the automatic shift speed is changed according to a downhill shift pattern different from the shift pattern used during normal running. Shifting control means A for downhill shifting
The automatic transmission control apparatus for a vehicle comprising, descending
It was operated to a forward traveling range other than D range while traveling on a slope.
That is detected and the driver's intention detecting means B for detecting the driver's intention regarding the downhill traveling based on this is detected , and the downhill shift pattern used during the downhill traveling in the D range is changed based on the detection result. The downhill shift pattern changing means C is provided.

The driver's intention detecting means B is D
Detects that the vehicle has been operated to a forward drive range other than range
Then, based on this, the driver's intent regarding downhill traveling is detected.
However, it is also possible to detect the intention of the driver regarding the downhill traveling from the time or the ratio of time when the operation is performed in this manner.

The shift pattern changing means C changes the downhill shift pattern in a direction of further deceleration when it is determined that the driver makes a deceleration request based on the detection result of the driver intention detecting means B. It is good to do.

When the downhill shift pattern defines a shift stage to be shifted according to the current shift stage, vehicle speed and gradient resistance, the shift pattern changing means C detects the driver intention detecting means B. Based on the result, when it is determined that the driver is requesting deceleration , the shift line on the downhill shift pattern may be moved to a side having a larger gradient resistance.

When the downhill shift pattern defines the shift stage to be shifted according to the current shift stage, vehicle speed and gradient resistance, the shift pattern changing means C detects the detection result of the driver intention detecting means. Based on the above, when it is determined that the driver is making a deceleration alleviation request, it is preferable to move the shift line on the downhill shift pattern to the side having a smaller gradient resistance.

[0013]

In the above structure, the driver's intention regarding the downhill traveling is detected, and based on this, the downhill traveling in the D range is performed.
By changing the downhill shift pattern used during traveling, not only the shift control during downhill traveling in the D range can be optimized, but also the driver's preference can be reflected. Time intent regarding downhill travel of the driver, with the engineered into the forward running range other than the D range during downhill travel, but determines that the deceleration demand, which is further operated in this way, Alternatively, the determination can be made more accurately by detecting the time ratio.

Regarding the change of the downhill speed change pattern, when the driver judges that the driver further requests deceleration, the downhill speed change pattern is changed in the direction of further deceleration.
It can be adapted to the driver's preferences. Further, when the downhill shift pattern defines the shift stage to be shifted according to the current shift stage, the vehicle speed and the gradient resistance, when it is determined that the driver further requests deceleration, , The shift line on the downhill shift pattern is moved to the side with a higher gradient resistance, and conversely, when it is determined that the driver is requesting deceleration relaxation, the shift line on the downhill shift pattern is changed to the gradient resistance. By moving it to the smaller side, it is possible to match the driver's preference.

[0015]

EXAMPLES Examples of the present invention will be described below. FIG. 2 is a system diagram of an embodiment of the present invention. The engine 1 is connected to the automatic transmission 2 so that the generated torque is transmitted to vehicle driving wheels (not shown). The automatic transmission 2 drives a torque converter 3 for inputting the torque generated by the engine 1 via a fluid, a multi-stage speed change gear mechanism 4 for inputting the output of the torque converter 3 and changing and outputting the output. It is composed of a hydraulic mechanism (not shown). Reference numeral 5 is a shift selector for range switching, and 6 is a transmission output shaft.

A plurality of solenoid valves (not shown) are incorporated in the hydraulic mechanism of the speed change gear mechanism 4, and the speed change gear mechanism 4 is internally provided by switching a combination of opening and closing (ON / OFF) of the plurality of solenoid valves. The engagement / disengagement combination of the respective clutches is switched so that the gear is shifted to a desired gear. The ON / OFF control of the plurality of solenoid valves is performed by the CPU,
This is performed based on a control signal from a control unit 10 including a microcomputer including a ROM, a RAM, an A / D converter, an input / output interface and the like.

An overrun clutch (not shown) in the speed change gear mechanism 4 opens an overrun solenoid valve (not shown) incorporated in the hydraulic mechanism (O).
N) is engaged (ON), whereby the engine brake can be activated during deceleration, and the control of this overrun solenoid valve is also based on the control signal from the control unit 10. Done.

Signals are input to the control unit 10 from various sensor switches for gear shift control. The various sensor switches are a vehicle speed sensor 11 that detects the vehicle speed VSP based on the rotation of the output shaft 6 of the automatic transmission 2, and a throttle opening TVO as an engine load.
A throttle sensor 12 for detecting the range, a range switch 13 for detecting the range position by the shift selector 5, an inhibitor switch 14 for detecting the gear position of the transmission gear mechanism 4,
Further, a brake switch 15 is provided which emits an ON signal when the brake pedal is depressed. Also, for the driver
Therefore, an operable mode switch 20 may be provided.
is there.

Here, the control unit 10
Performs shift control according to the shift control routine (first embodiment) shown in the flowchart of FIG. In step 1 (denoted as S1 in the figure; the same applies hereinafter), the input signals from the various sensor switches 11 to 15 are read. In step 2, it is determined whether or not the throttle opening TVO detected based on the signal from the throttle sensor 12 is less than or equal to a predetermined value (a value near the fully closed position). If YES, step 4
If NO, go to step 3.

In step 3, it is determined whether or not the state in which the throttle opening TVO exceeds the predetermined value has continued for a predetermined time or longer. If YES, it is determined that the vehicle is not in the downhill traveling state (deceleration state), the downshift shift control is prohibited, and the normal shift control is performed in step 51 described later.
(Or steps 51 to 53) and then to step 62. N
If O, go to step 4.

In step 4, the vehicle speed VSP detected based on the signal from the vehicle speed sensor 11 is a predetermined value (for example, 16 km).
/ h) Judge whether or not more than. If YES, it is determined that the vehicle is in a downhill traveling state (deceleration state), and step 11
Go to. If NO, it is determined that the vehicle is not in the downhill traveling state, the shift control for downhill is prohibited, and the routine proceeds to step 62 to perform normal shift control.

As described above, when the throttle opening TVO is equal to or less than the predetermined value and the vehicle speed VSP is equal to or more than the predetermined value, it is determined that the vehicle is in a downhill traveling state (deceleration state) and the downhill shift control is permitted. Even if the opening degree TVO exceeds a predetermined value, as long as it does not continue for a predetermined time or longer, the downhill shift control is permitted, and the routine proceeds to step 11. This is to prevent deterioration of drivability due to immediate switching between the downhill shift control and the normal shift control due to an unnecessary accelerator tilt or the like by the driver.

In step 11, based on the signal from the range switch 13, it is determined whether or not the current range is the D range, and further it is combined with the signal from the inhibitor switch 14 to determine whether the second range to the 4th speed of the D range. judge. If YES, the process proceeds to step 61 for the downhill shift control. If NO, the process proceeds to step 62 through step 12 (or steps 12 to 14) which will be described later, and normal shift control is performed. [Shift control for descending slope] In step 61, shift control for descending slope is performed according to the subroutine shown in the flowchart of FIG.

The downhill shift control subroutine of FIG. 4 will be described. This subroutine corresponds to downhill shift control means. In step 101, the vehicle speed (the number of revolutions of the output shaft 6 of the automatic transmission 2) VSP detected based on the signal from the vehicle speed sensor 11 and the current gear position detected based on the signal from the inhibitor switch 14 are set. From the gear ratio (gear ratio) Gr of the above, the turbine rotation speed (in other words, the input shaft rotation speed of the transmission gear mechanism 4) Nt which is the output shaft rotation speed of the torque converter 3 is calculated.

In step 102, from the calculated turbine speed Nt and the throttle opening TVO detected based on the signal from the throttle sensor 12, a turbine torque Tt preset and stored in accordance with these is mapped. See and ask. When the torque converter 3 is in the lockup state, it is desirable to provide another map for searching the turbine torque Tt in the lockup state.

[0026] At step 103, the vehicle speed VSP, determined by referring to a map rolling resistance + air resistance R _L of the vehicle that is set previously stored accordingly. The rolling resistance + air resistance _RL increases quadratically as the vehicle speed VSP increases. In step 104, the vehicle acceleration a = Δ is determined as the difference between the current detected value and the previous detected value of the vehicle speed VSP.
Calculate VSP.

In step 105, the turbine torque Tt
From the gear ratio (gear ratio) Gr, the rolling resistance + air resistance _RL, and the vehicle acceleration a, the gradient resistance equivalent value sin θ
Is calculated based on the following equation. sin θ = [Tt · Gr / r− ( _RL + W · a / g)] / W Where, Tt is turbine torque, Gr is gear ratio, r is tire radius, _RL is rolling resistance + air resistance, W is vehicle weight,
a is the vehicle acceleration, and g is the gravitational acceleration.

At step 106, the current gear position, the vehicle speed VSP, and the slope resistance equivalent value sinθ obtained at step 105 are calculated.
On the basis of the above, referring to the downhill shift patterns (FIGS. 5 to 7) set and stored in advance for each shift stage, the shift stage to be shifted and ON / OFF of the overrun clutch are determined. . The downhill shift pattern used here is shown in FIG.
~ It demonstrates by FIG.

FIG. 5 shows a case where the current gear stage is the second speed, and when the running state of the vehicle is in the area in the figure, the gradient resistance equivalent value sin θ is considered to be large on the minus side (for example, the downward gradient is large), and the gear shift is performed. The gear is maintained at the second speed and the overrun clutch (ovr / c) is actuated to strongly apply the engine brake so that the vehicle acceleration a approaches zero.

When the vehicle is in the area, the gradient resistance equivalent value sin θ is smaller in the minus side than in the area (for example, the downhill is small), so that the current state, that is, the second speed and the overrun clutch is OFF (normal running state) Immediately after the shift from the deceleration state to the deceleration state, etc.), if that state is maintained as described above when the second speed and the overrun clutch are turned ON, that state is maintained and careless ON / OFF of the overrun clutch The vehicle acceleration a is made to approach 0 while preventing deterioration of the vehicle drivability (hunting etc.).

When in the region, the gradient resistance equivalent value s
If inθ is smaller (downhill slope is smaller) and the vehicle is still in the 2nd speed, the vehicle will be decelerated too much, which will give the driver a feeling of braking. To prevent this, upshift to the 3rd speed and overdrive. The run clutch is turned on to weaken the effect of engine braking so that the vehicle acceleration a approaches zero.

When the vehicle is in the region, for example, when the downward gradient is smaller than that in the region, and in such a case, the feeling of braking becomes larger than in the region, and in order to prevent this, upshift to the fourth speed is performed. Then, reduce the effectiveness of engine braking. In the case of the 4th speed, the one-way clutch is not used, so that the engine brake works even if the overrun clutch is not actuated.

In this way, the drivability is prevented from deteriorating by performing the shift control so that the vehicle acceleration a approaches 0 when traveling down a slope. Next, a case where the current gear is the third speed will be described with reference to FIG. The current gear is 3
In the case of a high speed, if the gradient resistance equivalent value sin θ is in a large negative side, for example, it is assumed that the downward gradient is large, and the shift stage is downshifted to the second speed, the overrun clutch is turned on, and the engine brake is turned on. So that it works strongly.

When in the region, the gradient resistance equivalent value s
Since inθ is not so large on the minus side, the overrun clutch is turned on so that the engine brake is effective while maintaining the current gear. When the vehicle is in the region, the gradient resistance equivalent value sin θ is small, so if the current state, that is, the third speed and the state where the overrun clutch is OFF (immediately after shifting from the normal running state to the deceleration state, etc.) When the 3rd speed and the overrun clutch are turned on, the state is maintained to prevent deterioration of the vehicle drivability (hunting etc.) due to careless turning on / off of the overrun clutch, and The acceleration a of is made to approach 0.

When in the area, the gradient resistance equivalent value s
Since inθ is sufficiently small, the feeling of braking becomes larger than in the area. To prevent this, upshift to 4th speed, weaken the effect of engine braking, and make the vehicle acceleration close to 0. . In this way, the vehicle acceleration a is maintained at 0 to prevent deterioration of drivability during downhill traveling.

Next, the case where the current shift speed is the fourth speed will be described with reference to FIG. When the current gear stage is the fourth speed and the gradient resistance equivalent value sin θ is in the large negative side, for example, the downward gradient is large,
Downshift the gear to 2nd speed and turn on the overrun clutch so that the engine brake is applied strongly.

When in the area (10), the gradient resistance equivalent value
Since sin θ is not so large compared to the range, the shift speed is downshifted to the 3rd speed, the overrun clutch is turned on, and the effect of engine braking is weakened compared to the range. When in region (11), the slope resistance equivalent value s
Since inθ is sufficiently small, the current state, that is, the fourth speed is maintained, the effect of engine braking is further weakened, and the vehicle acceleration a approaches 0.

In this way, the vehicle acceleration a is maintained at 0 to prevent deterioration of the drivability of the vehicle when traveling downhill. In step 107 (FIG. 4), step 10
According to the determination in step 6, the shift solenoid valve and the overrun solenoid valve are drive-controlled to perform the downhill shift control. [Shift Control During Normal Travel] In step 62, normal shift control is performed according to the subroutine shown in the flowchart of FIG.

The normal shift control subroutine of FIG. 8 will be described. In step 201, the gear shift stage to be shifted is determined based on the vehicle speed VSP and the throttle opening TVO with reference to a preset and stored normal gear shift pattern (FIG. 9). At the same time, the overrun clutch is ON / O.
Determine FF. In step 202, according to the determination in step 201, the shift solenoid valve and the overrun solenoid valve are drive-controlled to perform normal shift control. [Change of Downhill Shift Pattern] Returning to FIG. 3, the change of the downhill shift pattern will be described.

When it is judged that the vehicle is traveling downhill (decelerated),
When it is determined that the range is not D, the process proceeds to step 11. In step 12, based on the signal from the range switch 13, it is determined whether the current range is 1 range or 2 ranges. This part corresponds to the driver's intention detecting means.

If YES, it means that the vehicle is operated to the forward traveling range (1 range or 2 range) other than the D range while traveling downhill, and it can be judged that the driver is requesting deceleration. Go to step 13. In step 13, the shift line on the downhill shift pattern is moved to the side having a larger slope resistance equivalent value sin θ in order to change the downhill shift pattern in the direction of further deceleration. This portion corresponds to the downhill shift pattern changing means.

Concretely explaining the example of the downhill shift pattern at the second speed shown in FIG. 5, the shift line is shifted as shown by the dotted line in FIG. After the change, the change flag F ₀ is set to 1 in step 14, and then the process proceeds to step 62 to perform normal shift control. Therefore, the changed downhill speed change pattern is not used immediately, but is used when driving in the D range during the subsequent downhill running, so that it matches the driver's preference.

If the determination in step 12 is NO,
Without changing the downhill shift pattern, the routine proceeds to step 62, where normal shift control is performed. On the other hand, when the accelerator is stepped on while traveling downhill and it is determined in step 3 that the throttle opening TVO exceeds the predetermined value for a predetermined time or more, the driver makes a deceleration alleviation request. Since it can be determined that it is doing so, the process proceeds to step 51.

At step 51, the value of the change flag F ₀ is judged. If F ₀ = 1 (during change), the routine proceeds to step 52, at which the downhill shift pattern is returned to the original one. That is, the shift line on the downhill shift pattern is moved to the side where the gradient resistance equivalent value sin θ is smaller. Specifically, the example of the downhill shift pattern for the second speed shown in FIG. 5 will be described. The shift line is shifted from the dotted line to the solid line in FIG.

After returning, the change flag F ₀ is reset to 0 in step 53, and then the routine proceeds to step 62, where normal shift control is performed. In this way, by detecting the driver's intention regarding downhill traveling and changing the downhill shift pattern based on this, not only the shift control during downhill traveling is optimized, but also the driver's preference. (Deceleration request or deceleration alleviation request) can be reflected.

Next, another embodiment will be described focusing on different points. FIG. 11 shows a shift control routine of the second embodiment. It is judged that the vehicle is running downhill (deceleration state),
If it is determined that the vehicle is in the D range in step 11, the timer Tmr is set to 0 in step 11 ', and then the process proceeds to step 61 to perform the downhill shift control.

If it is determined in step 11 that the range is not the D range, the process proceeds to step 12. In step 12, based on the signal from the range switch 13, it is determined whether the current range is 1 range or 2 ranges. If yes,
Since it means that the vehicle is operated to the forward traveling range (1 range or 2 range) other than the D range during traveling downhill, the timer Tmr is counted up in step 12 '.

Then, in step 12 ", it is determined whether or not the timer Tmr is equal to or greater than a predetermined value. If Tmr≥predetermined value, it is determined that the driver is requesting deceleration, and the process proceeds to step 13 to further reduce the speed. In order to change the downhill speed change pattern in the direction to move, the shift line on the downhill speed change pattern is moved to the side where the slope resistance equivalent value sin θ is larger. To do.

As described above, in this embodiment, D
Forward travel range other than range (1 range or 2 ranges)
The time (Tmr) operated to is detected, and when it is equal to or more than a predetermined value, it is determined that a deceleration request is made, and the downhill shift pattern is changed. Therefore, the steps 12 to 12 "correspond to the driver's intention detecting means, and the step 13 corresponds to the downhill shift pattern changing means.

12 to 13 show a shift control routine of the third embodiment. If it is determined in steps 2 to 4 that the vehicle is traveling downhill (decelerated), the process proceeds to step 21. In step 21, it is determined whether or not the vehicle is in the descending slope traveling state for a certain period of time, and if it is not the lapsed time, the process proceeds to step 25 without executing steps 22 to 24 described later.

In step 25, based on the signal from the range switch 13, it is determined whether or not the current range is the D range. If YES, the process proceeds to step 61 for the downhill shift control. If NO, go to step 26. In step 26, based on the signal from the range switch 13,
It is determined whether the current range is 1 range or 2 ranges.

If YES, it means that the vehicle has been operated to the forward traveling range (1 range or 2 range) other than the D range while traveling downhill, so that the timer Tmr is counted up at step 27. In this case, the routine proceeds to step 61, where shift control for downhill is performed. The timer Tmr is reset to 0 in step 55 when the vehicle is not traveling downhill.

Here, when a certain period of time has passed since it was determined that the vehicle is traveling on a downhill, the process proceeds from step 21 to step 22.
In step 22, it is determined whether or not the timer Tmr is equal to or greater than a predetermined value, and if Tmr ≧ predetermined value, it is determined that the driver is requesting deceleration, and the process proceeds to step 23, in which the vehicle further descends downhill. In order to change the vehicle speed change pattern, the speed change line on the downhill speed change pattern is moved to the side where the slope resistance equivalent value sin θ is large. Then, after the change flag F ₀ is set to 1 in step 24, the process proceeds to step 25.

As described above, in this embodiment, D
Forward travel range other than range (1 range or 2 ranges)
Time ratio (Tmr after a certain period of time)
Is detected, it is determined that a deceleration request is made when this value is equal to or greater than a predetermined value, and the downhill shift pattern is changed. Therefore, steps 21, 22, 26, and 27 correspond to driver's intention detecting means, and step 23 corresponds to downhill shift pattern changing means.

[0055]

As described above, according to the present invention, the driver's intention regarding downhill traveling is detected, and D
By changing the downhill shift pattern used during downhill driving in the range, not only can the shift control during downhill driving in the D range be optimized, but the driver's preference can be reflected. The effect is obtained.

The driver's intention regarding the downhill traveling is to detect that the vehicle is operated to the forward traveling range other than the D range during the downhill traveling, and with this, it is judged that the deceleration request is made.
However, the determination can be made more accurately by detecting the time or the time ratio of the operation as described above.

Regarding the change of the downhill speed change pattern, when the driver determines that the driver further requests deceleration, the downhill speed change pattern is changed in the direction of further deceleration.
It can be adapted to the driver's preferences.

If the downhill shift pattern defines the shift stage to be shifted according to the current shift stage, vehicle speed and gradient resistance, it is determined that the driver further requests deceleration. The shift line on the downhill shift pattern is moved to the side with a higher gradient resistance, and when it is determined that the driver is requesting deceleration reduction, the shift line on the downhill shift pattern is changed. It is possible to match the driver's preference by moving the vehicle to the side with smaller gradient resistance.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing the configuration of the present invention.

FIG. 2 is a system diagram showing an embodiment of the present invention.

FIG. 3 is a flowchart of a shift control routine of the first embodiment.

FIG. 4 is a flowchart of a downhill shift control subroutine.

FIG. 5 is a diagram showing a downhill speed change pattern at the second speed.

FIG. 6 is a diagram showing a downhill shift pattern at the third speed.

FIG. 7 is a diagram showing a downhill shift pattern at the 4th speed.

FIG. 8 is a flowchart of a normal shift control subroutine.

FIG. 9 is a diagram showing a normal shift pattern.

FIG. 10 is a diagram showing a change of a downhill shift pattern.

FIG. 11 is a flowchart of a shift control routine of the second embodiment.

FIG. 12 is a shift control routine of the third embodiment (first half).
Flow chart

FIG. 13 is a shift control routine of the third embodiment (second half).
Flow chart

[Explanation of symbols]

1 engine 2 automatic transmission 3 Torque converter 4 speed change gear mechanism 5 shift selector 6 Output shaft 10 Control unit 11 Vehicle speed sensor 12 Throttle sensor 13 Range switch 14 Inhibitor switch

─────────────────────────────────────────────────── --- Continuation of the front page (56) Reference JP-A-64-30959 (JP, A) JP-A-5-231518 (JP, A) JP-A-6-34044 (JP, A) JP-A-6- 109111 (JP, A) JP-A-63-68430 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 59/00-63/48

Claims (6)

(57) [Claims] 1. A range position is detected by a shift selector.
Range switch and whether the vehicle is traveling downhill
And a downhill shift control means for automatically changing the shift speed according to a downhill shift pattern different from the shift pattern used during normal running when traveling downhill in the D range . In the speed change control device, the vehicle is operated to a forward traveling range other than the D range while traveling downhill.
That is detected and the driver's intention detecting means for detecting the driver's intention regarding the downhill traveling based on this is detected , and the downhill shift pattern used during the downhill traveling in the D range is changed based on the detection result. A shift control device for an automatic transmission for a vehicle, comprising: downhill shift pattern changing means. 2. The driver's intention detecting means operates from a time when the vehicle is operated to a forward traveling range other than the D range while traveling downhill.
The shift control device for an automatic transmission for a vehicle according to claim 1, wherein the shift control device detects an intention of a person traveling on a downhill . 3. The driver's intention detecting means, based on a time ratio of operating to a forward traveling range other than the D range during traveling downhill ,
The shift control device for an automatic transmission for a vehicle according to claim 1, wherein the shift control device detects a driver's intention regarding traveling on a downhill . 4. The shift pattern changing means changes the downhill shift pattern in a direction of further deceleration when it is determined that the driver is making a deceleration request based on the detection result of the driver's intention detecting means. The method according to claim 1, wherein
The shift control device for an automatic transmission for a vehicle according to claim 3. 5. The downhill shift pattern defines a shift stage to be shifted according to the current shift stage, vehicle speed and gradient resistance, and the shift pattern changing means detects the driver's intention detecting means. The shift line on the downhill shift pattern is moved to a side having a larger gradient resistance when it is determined that the driver is making a deceleration request based on the result. The shift control device for an automatic transmission for a vehicle according to claim 3. 6. The downhill shift pattern defines a shift stage to be shifted according to the current shift stage, vehicle speed and gradient resistance, and the shift pattern changing means detects the driver's intention detecting means. The shift line on the downhill shift pattern is moved to a side having a smaller gradient resistance when it is determined that the driver makes a deceleration alleviation request based on the result. The shift control device for an automatic transmission for a vehicle according to claim 3 .