JP2669131B2 - Transmission control device for automatic transmission - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission of a vehicle, and in particular, to a gear shift in consideration of a road condition on which the vehicle travels, a vehicle condition, a driver's psychology, and the like. The present invention relates to a shift control device for an automatic transmission capable of controlling operation.

(Prior Art) An automatic transmission of a vehicle automatically shifts up or down its gear according to the running state of the vehicle. It is designed to be performed based on the throttle opening.

That is, in a shift control device that controls a shift operation of an automatic transmission, a plurality of upshift lines and a plurality of upshift lines that separate a low-speed region and a high-speed region from a vehicle speed and a throttle opening degree are provided. Based on these upshift line and downshift line, whether or not the gear position in the automatic transmission should be upshifted, or whether the downshift line should be downshifted based on the actual vehicle speed and the actual throttle opening. Is determined, and a shift-up or shift-down command signal is output.

For example, specifically describing the case where the shift speed is shifted up, the shift point determined by the actual vehicle speed and the actual throttle opening shifts from the low speed range to the high speed range across the upshift line. When this is done, a shift-up command signal is output from the transmission control device to the automatic transmission, whereby the automatic transmission changes its gear stage from the low gear stage to the high gear stage. Become.

(Problems to be Solved by the Invention) Since the upshift line and the downshift line are uniquely determined by the vehicle speed and the throttle opening as described above, depending on the traveling conditions of the vehicle,
The gear stage of the automatic transmission shifts undesirably, and
Upshifting and downshifting may be frequently repeated.

Explaining this point in detail, for example, when the vehicle travels at a relatively low speed on an uphill road with many curves or an urban area, the accelerator pedal may be depressed and released frequently, and the actual throttle The shift point, which is determined by the opening and the actual vehicle speed, is also greatly displaced, and
This shift point crosses the upshift line and the downshift line alternately and continuously. Therefore, when such a situation is reached, the shift speed of the automatic transmission frequently shifts between the low speed stage and the high speed stage, and stable running of the vehicle may be impaired.

The present invention has been made on the basis of the above-described circumstances, and has as its object the purpose of the present invention when a vehicle travels on an uphill road or a city area with a relatively low speed and many curves, or at a relatively high speed and a gentle speed. It is an object of the present invention to provide a shift control device for an automatic transmission that can ensure stable running of a vehicle even when traveling on an uphill road.

(Means for Solving the Problems) The present invention provides a vehicle speed detecting means for detecting a vehicle speed, an engine load detecting means for detecting an engine load, and an upshift line or a preset upshift line based on the vehicle speed and the engine load. When a shift point determined according to a shift pattern having a downshift line and a vehicle speed and an engine load crosses an upshift line or a downshift line, a shift command signal for upshifting from a low gear to a high gear or a low gear to a low gear. A shift control device for an automatic transmission, comprising: a shift command signal output unit that outputs a shift command signal for downshifting to a second gear; a vehicle speed change trend detecting unit that detects a trend of a vehicle speed; and a change trend of an engine load is detected. When the engine load change trend detection means and the gear shift command signal to be output,
Operating state inference means for inferring the operating state of the vehicle based on the changing trend of the vehicle speed and the changing trend of the engine load; When it is determined that the upshift line or the downshift line needs to be changed based on the determination result of the determination unit and the determination result of the determination unit, only the low vehicle speed region of the upshift line is changed to the high vehicle speed region. And a line shifting means for shifting only the high vehicle speed region of the downshift line toward the high load side of the engine load.

The shift command signal output means outputs a shift command signal to the automatic transmission when the upshift line or the downshift line is displaced and the shift point crosses the displaced shift line. It has become.

Preferably, the displacement means of the up or down shift line, according to the magnitude of the inference value by the driving state inference means,
A displacement changing means for changing the displacement of the shift line is included.

Further, it is preferable that the operating state inferring means infers the operating state by fuzzy inference.

(Operation) According to the shift control device for an automatic transmission of the above-mentioned claim 1, even if the shift line determined by the vehicle speed and the engine load crosses the upshift line or the downshift line, it is directed toward the automatic transmission. The shift command signal is not immediately output. That is, when the shift point crosses the upshift line or the downshift line, the operating state of the vehicle inferred based on the changing trend of the vehicle speed and the engine load requires a change of the upshift line or the downshift line. If the shift line is displaced and the shift point still crosses the displaced shift line, a corresponding shift command signal is output.

According to the speed change control device of the second aspect, the displacement amount of the shift line is varied according to the magnitude of the inference value by the operation state inference means. The inference value of is obtained by fuzzy inference.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

Referring to FIG. 1, an automatic transmission 2 combined with a vehicle engine 1 is schematically shown. The automatic transmission 2 is configured to receive a command signal from the shift control device 3 of one embodiment to shift up or down the shift speed. A command signal for upshifting or downshifting is output from the controller 4 to the hydraulic control circuit 2a of the automatic transmission 2.

The command signal is output from the controller 4 based on the throttle opening indicating the load of the engine 1 and the vehicle speed. For this reason, the controller 4 is electrically connected to the vehicle speed sensor 5 and the throttle opening sensor 6, and the controller 6 is supplied with the vehicle speed V and the throttle opening θ detected by these sensors 5, 6, respectively. It has become so. The throttle opening sensor 6 is provided with a valve opening of a throttle valve 7 provided in an intake passage to the engine 1,
That is, the throttle opening θ is detected, and the throttle valve 7 is operated in conjunction with the depression of the accelerator pedal 8 of the vehicle.

Then, in the memory (not shown) of the controller 4,
Upshift lines and downshift lines defined by the vehicle speed V and the throttle opening θ are mapped and stored in advance. Here, when the automatic transmission 2 has four shift speeds, the three upshift lines and three downshift lines are stored in the controller 4.

In FIG. 2, the horizontal axis represents the vehicle speed V and the vertical axis represents the throttle opening θ.
And, for example, when the shift stage of the automatic transmission 2 is in the third shift stage, a 3 → 4 upshift line Su for shifting up from the third shift stage to the fourth shift stage, and The downshift line Sd for downshifting from the 4th speed to the 3rd speed when in the 4th speed is shown. That is, the upshift line Su and the downshift line Sd divide the shift speed into the third speed region on the left side and the fourth speed region on the right side as viewed in FIG.

In the case of this embodiment, the upshift line Su rises vertically until the throttle opening becomes θu1 when the vehicle speed is the predetermined vehicle speed Vu1, and then the vehicle speed and the throttle opening are increased as the vehicle speed and the throttle opening increase, respectively. When it reaches Vu2, θu2, it rises to the right as seen in Fig. 2 and rises at a predetermined slope, and the throttle opening is maintained at θu2 while the vehicle speed is between Vu2 and Vu3. , It has the characteristic of rising vertically at a vehicle speed of Vu3 or higher.

On the other hand, the downshift line Sd has a vehicle speed Vd1 (Vd1 <Vu1).
In the case of 1), the vehicle vertically rises until the throttle opening θ becomes θd1 (θd1> θu1). Then, as the vehicle speed and the throttle opening increase, respectively, the vehicle speed and the throttle opening increase.
As shown in Fig. 2, the vehicle speed and throttle opening are further increased by Vd3, θd3 (Vu2 <Vd3 (Vu2 <Vd3
<Vu3, θd3> θu2) and also rise to the right and at a smaller gradient than before, and
Between the vehicle speeds Vd3 and Vd4 (Vd4 <Vu3), the throttle opening is maintained at θd3 (θu2 <θd3), and the vehicle has a characteristic that it rises vertically at a vehicle speed Vd4 or higher.

Therefore, the above-mentioned upshift line is provided in the controller 4.
If Su and the downshift line Sd are defined in advance, when the actual vehicle speed Va and the actual throttle opening θa are supplied to the controller 4 from the vehicle speed sensor 5 and the throttle opening sensor 6, respectively, in the controller 4, A point determined by the actual vehicle speed Va and the actual throttle opening θa, that is, when the shift point crosses the upshift line Su or the downshift line Sd, a command signal corresponding to the shift speed region where the shift point is located, that is, A shift-up or shift-down command signal can be output.

However, in the present invention, when the above-mentioned shift point crosses the upshift line Su or the downshift line Sd, the shift speed is not shifted unconditionally, but the shift point is shifted to the upshift line Su or the downshift line Su. Whether or not the gear should actually be shifted by fuzzy reasoning about the road condition, the vehicle condition and the driver's psychology that are currently running from the change trend of the throttle opening θ, the acceleration of the vehicle speed V, etc. when crossing the shift line Sd. And it is possible to select an optimal gear position suitable for each situation.

That is, FIG. 3 shows a flowchart which is a routine for outputting a 3 → 4 shift command signal.
The membership functions for performing fuzzy inference in the output routine of FIG. 3 are shown in FIGS.

Below, according to the flowchart of FIG. 3, 3 → 4
The output routine of the shift command signal will be described.

3 → 4 shift command signal output routine In this case, the vehicle is running, and the speed position of the automatic transmission 2 is in the third speed, and the output routine is as follows.
It is repeatedly performed every predetermined control cycle.

First, in step S1, the actual vehicle speed Va and the actual throttle opening θa are detected by the vehicle speed sensor 5 and the throttle opening sensor 6.
Are read respectively. The actual vehicle speed Va and the actual throttle opening θa are stored in the buffers VM and θM in the controller 4 in the next step S2, respectively.
It is used for discrimination in.

The buffers VM and θM sequentially store the actual vehicle speed Va and the actual throttle opening θa that are read one after another, and can store these actual data for, for example, past t1 time (for example, 1 sec).

In step S3, the actual vehicle speed Va and the actual throttle opening θa
It is determined whether or not the shift point obtained from and has crossed the upshift line Su (see FIG. 2). Here, as described above, immediately after this output routine is executed, since the automatic transmission 2 is in the third speed, the shift point is located on the left side divided by the upshift line Su in FIG. Is in the third speed range, and in this case, the determination in step S3 is negative (NO).
Then, the process returns to step S1.

Therefore, unless the determination in step S3 is positive (Yes), steps S1 to S3 are repeated. Here, with respect to the buffers VM and θM described above, after a lapse of t1 from the execution of this output routine, the data held therein for the time t1 is:
The oldest data can be rewritten to the latest data.

When the determination in step S3 becomes positive, that is, for example,
When the actual throttle opening θa becomes smaller as the depression of the accelerator pedal 8 decreases and the shift point crosses the upshift line Su of FIG. 2, in the next step S4, at that time, A throttle change rate Δθ of the throttle opening θ, a throttle opening θb before t1 hours and a deviation between a vehicle speed Vt before t1 hours and an actual vehicle speed at the present time, that is, an acceleration ΔV are obtained.

Here, each of the throttle change rate Δθ and the acceleration ΔV can be calculated from the following equation.

Δθ = θn-θn-1 ΔV = Δn-Vb In the above formula, θn-1 represents the throttle opening read in the previous time, θn represents the throttle opening read in this time, and Vn was read in this time. The vehicle speed, Vb, represents the vehicle speed t1 hours ago. θn−1, Vb is the above-mentioned buffer V
It can be obtained from the held data in M and θM, and similarly, the throttle opening θb can also be read and obtained from the held data in the buffer θM.

When Δθ, θb, ΔV are obtained in step S4,
In the next step S5, using these Δθ, θb, ΔV as variables, a value indicating the certainty that the part of the upshift line Su should be displaced, that is, the value of the membership function f indicating the certainty Is required.

Here, the membership functions f1, f2, and f3 in which Δθ, θb, and ΔV are variables are shown in FIGS. 4 to 6, respectively. The membership function f1 shown in FIG. 4 is such that after the throttle change rate Δθ has reached a predetermined negative value or less, the function value begins to gradually increase from 0, and then the throttle change rate Δθ further increases in the negative direction. It has such a characteristic that it increases sharply as it goes on and then converges to its maximum value of 1.

Also, the membership function f2 in FIG.
If the throttle opening θb before the time t1 is equal to or less than a predetermined value, the throttle opening θb takes a value of, for example, about 0.5, and rapidly increases toward 1, which is the maximum value, as the throttle opening θb increases. It has such characteristics.

Finally, the membership function f3 in FIG.
Is 0, the function value takes a predetermined value, for example, between 1 and 0.5, and as the acceleration ΔV increases in the positive direction, the function value decreases toward 0, whereas
As the acceleration ΔV increases in the negative direction, the acceleration ΔV increases toward the maximum value of 1.

Each of the membership functions f1, f2, and f3 described above is specifically mapped to a memory (not shown) in the controller 4 and stored in advance similarly to the above-described upshift line Su and downshift line Sd. Therefore, in step S5, from Δθ, θb, and ΔV obtained in step S4,
The value of each membership function, ie, f1 (Δθ), f2
(Θb), f3 (ΔV) are obtained.

Function values f1 (Δθ), f2 (θb),
f3 (ΔV) is the sum of these values at step S6,
That is, the determination amount is calculated. In this embodiment, when adding each function value, each function value is multiplied by a predetermined weight coefficient 1, m, n. That is, the determination value F is
It can be calculated based on the following formula.

F = Σfn = lf1 (Δθ) + mf2 (θb) + nf3 (ΔV) Here, the weighting factors l, m, n take positive values up to 1, for example, and these values can be set appropriately.

In the next step S7, the calculated determination amount F is, for example, 1.
It is determined whether it is 5 or more.If the determination is no, the process immediately proceeds to step S8.However, if the determination is positive, the process proceeds to step S8 via steps S9 and S10. Become.

If the determination in step S7 is positive, that is, the determination amount F
When the value is 1.5 or more, the following traveling situations are conceivable, as is apparent from FIGS. 4 to 6.

First, there is a case where the acceleration ΔV takes a small positive value even though the throttle opening θb before t1 time is large, and in this case, the vehicle is climbing a steep slope. You can judge.

The second is a case where the throttle opening degree θb is equal to or more than the intermediate degree and the throttle change rate Δθ takes a large negative value (the accelerator pedal 8 is returned). It can be determined that an obstacle such as a traffic jam, a signal waiting, a pedestrian or another vehicle jumping out was encountered while running.

If the determination in step S7 is positive, the aforementioned step S9
Proceeding to step 1, in this step, the displacement amount ΔX1 for displacing the low vehicle speed region portion of the upshift line Su to the high vehicle speed region side is determined based on the determination amount F. Specifically, the amount of displacement Δ
X1 will be obtained from the map shown in FIG. 7 based on the magnitude of the determination amount F, but here, the value of the displacement amount ΔX1 is limited to the range in which the engine braking of the third speed does not work. Should. As is clear from FIG. 7, the amount of change Δ
X1 takes a predetermined value when the determination amount F is 1.5, and takes a larger value as the determination amount F increases.

In the next step S10, the low vehicle speed region of the upshift line Su is moved to the high vehicle speed region based on the displacement amount ΔX1 obtained in the previous step. There are various ways to move the low vehicle speed region, that is, how to correct the upshift line Su. In the case of this embodiment, as shown by a broken line in FIG. The upshift line Su is corrected by cutting the low vehicle speed region in the shift line Su.
Vu1 can be moved from 30km / h to 50km / h.

In the next step S8, similarly to the case of the determination in step S3, it is determined whether or not the shift point obtained from the actual vehicle speed Va and the actual throttle opening θa read in step S1 crosses the upshift line Su. , Upshift line Su here
Is either corrected in step S10 or is maintained as it is.

If the determination in step S8 is positive, the next step S1
At 1, the controller 4 outputs a shift-up command signal to the automatic transmission 2, whereby the gear stage of the automatic transmission 2 is shifted from the third speed to the fourth speed. On the other hand, if the determination in step S8 is negative, step
It bypasses S11 and returns to step S1.

According to the 3 → 4 shift command signal output routine described above, when the driver returns the accelerator pedal 8 as shown in FIG. 8, the actual throttle opening θa is greatly reduced. Degree θa and actual vehicle speed
When the shift point determined by Va moves from the A position to the B position in FIG. 2, in this case, the determination in step S3 described above becomes positive, and the steps after step S4 are performed. Will be implemented. Then, in the process in which the steps after step S4 are performed, if the determination in step S7 is positive, as described above, it is as if the vehicle is approaching a curve while climbing a steep uphill. Situation or
While traveling in an urban area, it is determined that the vehicle encounters the above-described obstacle, and in this case, based on the displacement ΔX1 calculated in step S9, in step S8, the low vehicle speed region of the upshift line Su is determined. Is corrected as described above. Therefore, in the next step S8, the corrected upshift line Su
From the B position, it is determined whether or not the shift point outputs a shift-up command signal. In this case, if the up-shift line Su is corrected as shown by the broken line in FIG. Since the determination in step S8 is negative, step S11 is not performed, and thus, at this time, no upshift command signal is output. After this, if the vehicle is turning a curve, it reaches the middle or the end, or if the vehicle is driving in the city, the above-mentioned obstacle is eliminated. Will be stepped on again, and the next time step S3 is performed,
If the shift point is moved to the position C in FIG. 2, in this case, the determination in step S3 is negative, so that the gear stage of the automatic transmission 2 is set to the third speed as shown in FIG. It is maintained and it is possible to prevent undesired shift-up.

On the other hand, in the conventional case, the return signal of the accelerator pedal 8 causes the shift point to be shifted from the position A to the position B, and immediately after crossing the upshift line Su, an upshift command signal is output. As shown by the broken line in FIG. 8, the gear stage of the automatic transmission 2 is shifted up from the third speed to the fourth speed. In a situation where the accelerator pedal 8 is depressed thereafter and the shift point returns from the position B to the position A again, in this case, the shift point crosses the above-described downshift line Sd. In this case, the downshift command signal is output, and the shift stage of the automatic transmission 2 is downshifted from the fourth speed to the third speed. Therefore, in the conventional case, for example, when the vehicle is climbing the uphill, at the entrance and exit of the curve, as shown by the dashed circles in FIG. Since each of these operations is performed, upshifting and downshifting of the shift speed are undesirably repeated.

Next, the 4 → 3 shift command signal output routine will be described with reference to the flowchart of FIG. 9 and the map of FIG.

4 → 3 Shift Command Signal Output Routine Since the flowchart of FIG. 9 includes the same steps and corresponding steps as the flowchart of FIG. 3, the same steps are denoted by the same step numbers. The description thereof will be omitted, and with respect to the corresponding step, a dash is added to the step number, and only the difference will be described.

In this routine, the gear position of the automatic transmission 2 is at the 4th speed. Therefore, the determination at step S3 'is that there are 4 shift points obtained from the actual vehicle speed Va and the actual throttle opening θa.
It is determined whether or not the vehicle has moved from the speed range to the third speed range across the downshift line Sd.

If the determination in step S3 'is positive, the process proceeds to step S5' via step S4.In this step S5 ', instead of the membership function f1, a membership function f4 having a throttle change rate Δθ as a variable is applied. Is done. This membership function f4 is, as shown in the map of FIG. 10,
When the throttle change rate Δθ is 0, the maximum value is 1, and the throttle change rate Δθ decreases toward 0 as the throttle change rate θ increases in the positive direction.

In step S5 ', each membership function f4, f2, f3
Is determined, that is, f4 (Δθ), f2 (θb), f3 (ΔV), the determination amount F is calculated from the following equation in the next step S6 ′.

F = Σfn = lf4 (Δθ) + mf2 (θh) + nf3 (ΔV) If the determination in step S7 becomes positive, then step S1
0 'is implemented. In this step, downshift line S
As shown by the dashed line in FIG. 2, the high vehicle speed region of d has a predetermined displacement amount Δ on the large opening side of the throttle opening θ.
It is corrected so that X2 is translated. For example, in the case of this embodiment, the high vehicle speed region of the downshift line Sd is a region between Vd2 and Vd4 in terms of the vehicle speed V. Here, the displacement amount ΔX2 is set to a constant amount. However, as in the case of the displacement amount ΔX1 described above, the determination amount F
You may make it variable according to the magnitude of.

From step S7 or step S10 ', step S8',
S11 'is sequentially performed. In this case, in step S8', the downshift line Sd or the original downshift line Sd in which the shift point determined from the actual vehicle speed Va and the actual throttle opening θa is corrected. Is determined, and if the determination is positive, a shift down command signal is output to the automatic transmission 2 from step S11 ′, whereby the gear position of the automatic transmission 2 is set to 4 It will be downshifted from the third speed to the third speed.

According to the above-described output routine of the 4 → 3 shift command signal, when the shift point moves from the position D to the position E in FIG. 2, the determination in step S3 becomes positive, and the steps after step S4 are performed. Will be. At this time, the case where the determination in step S7 is positive means that the acceleration ΔV is close to 0 and the throttle change rate Δθ is also positive, as is apparent from FIGS. 5, 6, and 10. When the vehicle is traveling at a relatively high speed,
It can be determined that the vehicle is approaching a gentle ascent and that the accelerator pedal 8 is slowly and slightly depressed. In such a driving situation, in step S10 ',
As described above, since the high vehicle speed range portion of the downshift line Sd is displaced by the predetermined amount ΔX2, the determination in this step will not be positive even if the step S8 ′ is executed next time.
Therefore, in this case, even if the shift point moves from the D position to the E position, the downshift command signal is not output, so that the shift speed of the automatic transmission 2 is maintained at the fourth speed. As a result, an undesired downshift can be prevented.

On the other hand, in the conventional case, when the shift point moves from the D position to the E position, the gear position of the automatic transmission 2 is immediately downshifted from the 4th speed to the 3rd speed, and after that, In response to the fact that the actual vehicle speed Va has increased as a result of this downshift, the situation where the depression of the accelerator pedal 8 is returned to its original state, that is, as shown in FIG. When the gear shifts from the E position to the G position, the shift point crosses the upshift line Su, so that the gear position of the automatic transmission 2 is shifted up from the third speed to the fourth speed. Undesired hunting occurs in the shift operation of the automatic transmission 2. However, in the case of the present invention, first, the undesired downshift from the fourth speed to the third speed is prevented, so that the aforementioned undesired hunting can be prevented.

In both the 3 → 4 shift command signal output routine and the 4 → 3 shift command signal output routine of the present invention, the upshift line Su and the downshift line Sd receive the determination result in step S7, Since only a part of the displacement is displaced, the operation of the normal driving situation can use the area of the upshift line Su and downshift line Sd which is not corrected so far, causing a feeling of strangeness in normal driving Nothing to do.

The present invention is not limited to the above-described embodiment, and various modifications are possible. For example, in one embodiment, the upshift line Su and the downshift line Sd are
And the throttle opening θ, but instead of the vehicle speed V, a transfer drive gear rotation speed of the automatic transmission 2 substantially corresponding to the vehicle speed V is used. , The upshift line Su and the downshift line Sd may be defined respectively,
The manner of displacement of the low and high vehicle speed regions on the upshift line Su and the downshift line Sd, that is, the manner of correction thereof, is not limited to the example shown in FIG.

(Effect of the Invention) As described above, according to the shift control device for an automatic transmission of the present invention, an upshift line or a downshift line is defined based on the vehicle speed and the engine load, and the vehicle speed and the engine load are defined. When the shift point determined from the above crosses the upshift line or the downshift line, the shift line is displaced based on the estimated value of the driving state of the vehicle estimated from the change in the vehicle speed and the engine load, and , When the shift point still crosses the displaced shift line,
A shift command signal is output. Therefore, when the vehicle is traveling on an uphill road with many curves or an urban area at a relatively low speed, it is possible to reduce an undesired upshift of the shift speed.
In addition, it is possible to reduce undesired downshifts while traveling on a moderately uphill road at a relatively high speed, and to improve traveling stability of the vehicle.

Further, if the amount of displacement of the upshift line or the downshift line is varied in accordance with the magnitude of the estimated value in the driving state, undesired shift operations can be more effectively reduced, and the estimated value of the driving state can be reduced. Is obtained from fuzzy inference, there is an advantage that the estimated value of the driving state can be accurately obtained.

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a schematic view showing the structure of a shift control device, and FIG. 2 is an upshift line of an automatic transmission defined by a vehicle speed and a throttle opening. A graph showing a downshift line, FIG. 3 is a flowchart showing a 3 → 4 shift command signal output routine, and FIGS. 4 to 6 are members using a throttle variable, a throttle opening before t1 time and an acceleration as variables. FIG. 7 is a graph showing the amount of displacement of the upshift line with respect to the determination amount, FIG. 8 is a graph showing the change in the throttle opening, the vehicle speed and the gear position with respect to time, and FIG. ,
FIG. 10 is a flowchart showing a 4 → 3 shift command signal output routine, and FIG. 10 is a graph showing a membership function with the throttle change rate as a variable. DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Automatic transmission, 3 ... Shift control device, 4 ... Controller, 5 ... Vehicle speed sensor, 6 ... Throttle opening degree sensor, 8 ... Accelerator pedal.

Claims (5)

(57) [Claims] 1. A vehicle speed detection means for detecting a vehicle speed, an engine load detection means for detecting an engine load, a shift pattern having an upshift line preset based on the vehicle speed and the engine load, A shift command signal output means for outputting a shift command signal for upshifting from a low gear to a high gear when a shift point determined according to a vehicle speed and the engine load crosses the upshift line. In the shift control device, a vehicle speed change trend detecting means for detecting the change trend of the vehicle speed; an engine load change trend detecting means for detecting the change trend of the engine load; A driving state inference means for inferring a driving state of the vehicle based on the change trend and the change trend of the engine load; Based on the inferred value by the step, the upshift line change determining means determines whether the upshift line needs to be changed, and the upshift line needs to be changed based on the determination result of the determining means. And an upshift line displacing means for displacing only the low vehicle speed region of the upshift line toward the high speed vehicle region when the upshift line is displaced. Outputs a shift command signal to the automatic transmission when the shift point crosses the displaced upshift line. 2. The apparatus according to claim 1, wherein said upshift line displacement means includes a displacement amount changing means for changing a displacement amount of said upshift line in accordance with a magnitude of an inference value by said operating state inference means. 1. A shift control device for an automatic transmission according to 1. 3. A vehicle speed detecting means for detecting a vehicle speed, an engine load detecting means for detecting an engine load, a shift pattern having a downshift line preset based on the vehicle speed and the engine load, A shift command signal output means for outputting a shift command signal for downshifting from a high speed stage to a low speed stage when a shift point determined according to a vehicle speed and the engine load crosses the downshift line. In the shift control device, the vehicle speed change trend detecting means for detecting the vehicle speed change trend, the engine load trend detecting means for detecting the engine load change trend, and the vehicle speed change trend and the engine load change trend. A driving state inference means for deducing the driving state of the vehicle based on the driving state inference means; Downshift line change determining means for determining whether or not the downshift line needs to be changed, and the downshift line is determined when it is determined that the downshift line needs to be changed based on the determination result of the determining means. Downshift line displacing means for displacing only the high vehicle speed region of the line to the high load side of the engine load, wherein the shift command output means is displaced when the downshift line is displaced. A shift control device for an automatic transmission, which outputs a shift command signal to the automatic transmission when the shift point crosses a downshift line. 4. The downshift line displacement means includes displacement amount changing means for changing a displacement amount of the downshift line in accordance with a magnitude of an inference value by the operating state inference means. 3. A shift control device for an automatic transmission according to item 3. 5. The operating state inference means infers the operating state by fuzzy inference.
Alternatively, the shift control device for the automatic transmission according to item 2.