JP3581234B2 - Transmission control device for automatic transmission - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a shift control device for an automatic transmission mounted on a vehicle.
[0002]
[Prior art]
2. Description of the Related Art As a conventional shift control device for controlling a shift of an automatic transmission mounted on a vehicle such as an automobile, there is a shift control device described in, for example, Japanese Patent Application Laid-Open No. 4-194448.
[0003]
The shift control device disclosed in the above publication includes a throttle opening sensor for detecting a throttle opening, a throttle changing speed calculating means for calculating a changing speed of the throttle opening using these signals, and a throttle opening changing speed. Comparing means for comparing the set value with a predetermined value; kick-down permitting means for controlling a shift in accordance with a shift pattern having a kick-down shift region when the rate of change of the throttle opening is larger than the predetermined value; If the change speed of the speed change is smaller than a predetermined value, the shift speed is controlled in accordance with a speed change pattern having no kick down speed change area.
[0004]
According to the above configuration, when the throttle opening increases relatively rapidly and the throttle opening becomes equal to or more than a predetermined value, the vehicle enters a kick-down region, the speed of the shift vehicle rapidly increases, and the changing speed of the throttle opening decreases. In this case, the shift control is performed according to the shift pattern in which the kick-down shift region does not exist. Therefore, even if the throttle opening exceeds a predetermined value, the shift speed can be maintained without abrupt change in the shift vehicle speed. It has become.
[0005]
This means that if the accelerator pedal is depressed gently on an uphill, it will be possible to drive at the same gear without downshifting, improving ride comfort and improving fuel consumption. Has an effect.
[0006]
[Problems to be solved by the invention]
However, since the conventional shift control device of the automatic transmission employs a shift pattern in which both the upshift line and the downshift line are moved to the high speed side at the time of the auto power, the acceleration when the accelerator pedal is depressed is obtained. However, a function to prevent a downshift when the accelerator is on or a busy shift prevention function to prevent an upshift when the accelerator is off cannot be obtained sufficiently. An upshift is performed, which affects the riding comfort of the vehicle.
[0007]
In addition, when the vehicle is decelerated by depressing the brake pedal, the auto power mode is automatically canceled. Therefore, when the vehicle accelerates again after deceleration, sufficient acceleration cannot be obtained.
[0008]
The present invention has been made to solve such a problem. In the case of sudden acceleration / deceleration, a busy shift prevention mode is adopted in which the upshift line of the shift pattern is extended to the high speed side and the downshift line of the shift pattern is extended to the low speed side. Accordingly, it is an object of the present invention to provide a shift control device for an automatic transmission in which ride comfort is improved and acceleration performance after deceleration is improved.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 includes an engine load change speed detecting means for detecting a change speed of an engine load, an engine load detecting means for detecting an engine load, and a vehicle speed detecting means for detecting a vehicle speed. Acceleration / deceleration detection means for detecting the acceleration / deceleration of the vehicle, brake operation detection means for detecting whether or not the brake is operated, and an engine load, a change speed of the engine load, a vehicle speed, an acceleration / deceleration of the vehicle, and a brake operation. A driving condition detecting means for detecting a driving condition from presence / absence, a mode switching device for selecting a normal driving mode or a busy shift prevention mode according to the driving condition output from the driving condition detecting device, and an output from the engine load detecting device. From the engine load, the vehicle speed outputted from the vehicle speed detecting means and the shift mode outputted from the mode switching means Gear shift command means for determining the gear position and controlling the automatic transmission, and detecting whether the vehicle is rapidly accelerating or decelerating or high-speed driving based on the driving condition output from the driving condition detecting means. In such a case, the mode is switched to the busy shift prevention mode in which the gap between the speed-up line and the speed-down line in the speed change pattern is appropriately widened from the normal travel mode, and in the case of high-speed travel or small acceleration / deceleration, the mode is switched to the normal travel mode. It was done.
[0010]
With the above configuration, when the vehicle is suddenly accelerated or decelerated, the mode is switched to the busy shift prevention mode, and the upshift of the shift pattern in the shift pattern is shifted to the high speed side, and the shift down line is shifted to the low speed side. Since the downshift is performed, the upshift and downshift during sudden acceleration / deceleration can be reliably prevented.
[0011]
In order to achieve the above object, the invention according to claim 2 is characterized in that when the engine load change speed detected by the engine load change speed detecting means exceeds a predetermined value in the negative direction, or when the acceleration / deceleration detecting means detects the vehicle, When a predetermined time has elapsed since the deceleration exceeded the predetermined value, the mode was switched from the normal traveling mode to the busy shift prevention mode, and the engine load change speed detected by the engine load change speed detection unit and the vehicle speed detection unit detected. When the vehicle speed and the acceleration / deceleration of the vehicle detected by the acceleration / deceleration detection means are within a predetermined value for a predetermined time or more, switching from the busy shift prevention mode to the normal traveling mode is performed. It was done.
[0012]
According to the above configuration, switching from the normal traveling mode to the busy shift preventing mode or switching from the busy shift preventing mode to the normal traveling mode can be smoothly and reliably performed according to the traveling state of the vehicle.
[0013]
In order to achieve the above object, the invention according to claim 3 is characterized in that the shift instructing means detects the engine load change detected by the engine load change speed detecting means when the driving force priority mode selected by the mode switching means is released. The mode is switched to the busy shift prevention mode or the normal traveling mode according to the speed, the speed of the vehicle detected by the vehicle speed detecting means or the acceleration / deceleration of the vehicle detected by the acceleration / deceleration detecting means.
[0014]
According to the above configuration, switching from the driving force priority mode to the busy shift prevention mode or the normal traveling mode can be performed smoothly and reliably according to the traveling state of the vehicle.
[0015]
In order to achieve the above object, the invention according to claim 4 provides an engine brake mode in which, when the deceleration of the vehicle by the brake exceeds a predetermined value for a predetermined time, the engine brake mode is downshifted to make the engine brake more effective than in the normal driving mode. After the end of the engine brake mode, the mode is switched to the busy shift prevention mode.
[0016]
With the above configuration, when the vehicle is suddenly decelerated by the brake, the mode is switched to the engine brake mode, the engine brake is effectively operated, and when the accelerator is depressed again for acceleration, the mode is switched from the engine brake mode to the busy shift prevention mode. Therefore, an upshift and a downshift during sudden acceleration can be prevented.
[0017]
In order to achieve the above object, in the invention according to claim 5, in the busy shift prevention mode, the shift up line of the shift pattern is extended to a higher speed side than the normal drive mode, and the shift down line is set to be the same as the normal drive mode. Things.
[0018]
With the above configuration, in the case of sudden acceleration in the normal traveling mode, the normal traveling pattern can be switched to the busy shift prevention pattern to obtain more rapid acceleration, and in the case of sudden deceleration, the normal traveling mode pattern can be maintained. This prevents a drop in ride quality due to sudden deceleration and a vehicle swap.
[0019]
According to a sixth aspect of the present invention, in the busy shift prevention mode, when the speed change command means is rapidly decelerated in the driving force priority mode, the speed change down line of the speed change pattern is expanded toward the speed reduction side. In the case of rapid acceleration, the driving force priority mode is maintained.
[0020]
With the above configuration, in the case of sudden deceleration in the driving force priority mode, switching from the normal traveling pattern to the busy shift prevention pattern is performed to prevent a decrease in ride comfort due to sudden sudden deceleration, and in the case of sudden acceleration, A sharper acceleration can be obtained while maintaining the driving force priority pattern.
[0021]
In order to achieve the above object, the invention according to claim 7 is characterized in that, when the speed change command means is rapidly decelerated during traveling in a low speed range in the engine brake mode, the speed change down line of the speed change pattern is expanded toward the speed reduction side. The mode is switched to the busy shift prevention mode, and the engine brake mode is maintained when the vehicle is suddenly decelerated during traveling in the high speed range in the engine brake mode.
[0022]
With the above configuration, when the vehicle is suddenly decelerated by operating the engine brake during traveling in a lower speed range, the mode is switched to the busy shift prevention mode in which the downshift line of the shift pattern is expanded to the deceleration side, and the sudden rapid deceleration is performed. A decrease in ride quality is prevented, and when the vehicle is suddenly decelerated by performing an engine brake operation during traveling in a higher speed range, a more rapid deceleration can be obtained by using an engine brake mode shift pattern.
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described in detail with reference to the drawings.
[0023]
FIG. 1 is a block diagram showing a shift control device of an automatic transmission. 1 is an engine load change speed detecting means for detecting a change speed of the engine load detected by an engine load detecting means 2; 3 is a vehicle speed detecting means for detecting the speed of the vehicle, 4 is an acceleration / deceleration detecting means for detecting the acceleration or deceleration of the vehicle based on the vehicle speed signal detected by the vehicle speed detecting means. 6 shows a brake operation detecting means for detecting whether or not the brake is operated.
[0024]
The signals detected by these detecting means are input to the transmission control device main body 6.
[0025]
In the transmission control device body 6, the change speed of the engine load detected by the engine load change speed detecting means 1, the engine load detected by the engine load detecting means 2, the vehicle speed signal detected by the vehicle speed detecting means 3, the acceleration / deceleration A driving situation detecting means 7 for detecting the driving situation of the vehicle from the acceleration / deceleration or deceleration of the vehicle detected by the detecting means 4 and a brake operation signal detected by the braking operation detecting means 5, and a driving situation detected by the driving situation detecting means 7 Mode switching means 8 for selecting a shift mode according to the speed change mode, a shift mode output from the traveling mode switching means 8, an engine load output from the engine load detecting means 2, and an output from the engine load and vehicle speed detecting means 3 A gear change command that determines the gear to be switched according to the vehicle speed to be performed and controls the automatic transmission 10 to achieve the determined gear. 9 is provided.
[0026]
On the other hand, in the mode switching means 8 of the shift control device body 6, four shift modes of a normal running mode, a driving force priority mode, a busy shift prevention mode, and an engine brake mode are set in advance, and the running situation detecting means 7 These shift modes can be selected in accordance with the running condition.
[0027]
The shift pattern in the normal running mode is shown in FIG. 2 based on the relationship between the throttle opening (TH opening) and the vehicle speed, and the shift pattern in the driving force priority mode is shown in FIG. The shift pattern in FIG. 4 is preset as shown in FIG. 4, and the shift pattern in the engine brake mode is preset as shown in FIG.
[0028]
That is, in each shift mode, the upshift is performed along the upshift line (solid line) during acceleration, and the downshift is performed along the downshift line (dashed line) during deceleration due to the relationship between the TH opening and the vehicle speed. , When the TH opening is large, or in the middle / low speed range where the TH closing speed is not large or the deceleration is not small, the busy shift prevention mode (in the case of sudden acceleration / deceleration, the normal driving mode, the driving force priority mode, or the engine braking mode The shift up line of the shift pattern is set to the high speed side, and the shift down line is set to the low speed side). The acceleration / deceleration is small, the TH opening is small, and it is continuous for a certain period of time. If so, the busy shift prevention mode is canceled.
[0029]
When the vehicle is suddenly decelerated by sudden braking, the mode is switched to the engine brake mode, and a downshift is performed.
[0030]
That is, in the present embodiment, the busy shift prevention mode pattern shown in FIG. 4 is different from the normal travel mode gear shift pattern shown in FIG. 2 in that the shift up line (solid line) of the gear shift pattern is expanded toward the high speed side. In this mode, a sudden acceleration is obtained, and in the case of a sudden deceleration, it is intended to maintain the rapid deceleration performance by setting the same as the downshift line (broken line) of the normal traveling mode shift pattern. .
[0031]
In contrast to the driving force priority mode shift pattern shown in FIG. 3, the busy shift prevention mode pattern shown in FIG. 4 is set to a busy shift prevention mode in which the shift down line (dashed line) of the shift pattern is extended to a lower speed side. This prevents a drop in ride quality due to sudden sudden deceleration, and in the case of sudden acceleration, it is intended to obtain more rapid acceleration by setting the same as the shift up line (solid line) of the driving force priority mode shift pattern. .
[0032]
In contrast to the engine brake mode shift pattern shown in FIG. 5, the busy shift prevention mode pattern shown in FIG. 4 has a shift down pattern of the shift pattern when the engine brake operation is performed during traveling in a lower speed range and the vehicle is suddenly decelerated. By switching to the busy shift prevention mode in which the line (dashed line) is extended to the deceleration side, the ride comfort is prevented from deteriorating due to sudden sudden deceleration. Is intended to be rapidly decelerated in the same manner as the shift up line (solid line) of the engine brake mode shift pattern.
[0033]
Next, the operation will be described with reference to the flowcharts shown in FIGS.
[0034]
When the vehicle starts running, it is determined according to the flowchart shown in FIG. 6 whether the mode is the busy shift prevention mode.
[0035]
That is, in step S1 of the flowchart shown in FIG. 6, it is determined whether the current vehicle speed is high. If the vehicle speed is high, the process proceeds to step S15. If not, the process proceeds to step S2.
[0036]
In step S2, if the vehicle speed is low, the process proceeds to step 9, and if not, the process proceeds to step 3.
[0037]
In step S3, it is determined whether the TH closing speed is high. If the speed is high, the process proceeds to step S8, the busy shift prevention mode flag is set to 1, and the flow ends.
[0038]
If the TH closing speed is not high, the process proceeds to step S4, where it is determined whether the brake switch (SW) is on and the deceleration is large. If it is, the process proceeds to step S8 to set the busy shift prevention mode flag. Set to 1 to end the flow, and if the deceleration is not large, proceed to step S5.
[0039]
In step S5, it is determined whether the normal traveling condition is satisfied (continuous) for a certain period of time.
[0040]
The normal traveling condition is satisfied when the condition that the absolute value of the TH opening speed is within a certain value, the absolute value of the acceleration / deceleration is within a certain value, and the TH opening is within a certain value is continued for a certain period of time. .
[0041]
If the normal driving condition is satisfied for a certain period of time, the process proceeds to step S7, the busy shift prevention mode flag is set to 0, the engine brake mode flag is set to 0, and the flow is terminated. If not, the flow advances to step S6 to set the busy shift prevention mode flag to 1 and end the flow.
[0042]
On the other hand, in step S9, it is determined whether the TH opening is large. If the TH opening is large, the process proceeds to step S13. If not, the process proceeds to step S10.
[0043]
In step 10, it is determined whether the idle switch (SW) is off. If the idle switch is off, the flow is terminated. If it is on, the process proceeds to S11 to determine whether the brake SW is off.
[0044]
If it is off, the flow ends. If it is on, the process proceeds to step S12, the busy shift prevention mode flag is set to 0, and the flow ends.
[0045]
In step S13, it is determined whether the TH opening is large. If the TH opening is large, the process proceeds to step S14. If not, the process proceeds to step S10, and the flow proceeds through steps S10, S11, and S12 described above. When the process ends and the process proceeds to step S14, the busy shift prevention mode flag is set to 1 and the flow ends.
[0046]
If the process proceeds from step S1 to step S15, the busy shift prevention mode flag is set to 0, and the engine brake mode flag is set to 0, and the flow is terminated.
[0047]
Similarly, the determination as to whether the mode is the driving force priority mode or the engine braking mode is performed according to the flowcharts shown in FIGS.
[0048]
First, it is determined in step S20 of the flowchart for determining the driving force priority mode shown in FIG. 7 whether the TH opening speed is high. If the TH opening speed is high, the process proceeds to step S27. If not, the process proceeds to step S21.
[0049]
In step S21, it is determined whether the driving force priority mode is set. If the driving force priority mode plug 1 is selected, the process proceeds to step S25. If the driving force priority mode plug is not determined, in step S22, it is determined whether the current vehicle speed is high. Is performed.
[0050]
If the vehicle speed is high, the process proceeds to step S24. If the vehicle speed is not high, the process proceeds to step S23, where the busy shift prevention mode flag is set to "1", and the flow ends.
[0051]
In step S24, the busy shift prevention mode flag is set to "0", and the engine brake mode flag is set to "0", and the flow ends.
[0052]
In the above step S25, it is determined whether or not the state where the TH opening is small has continued for a certain period of time. If the state has continued, the process proceeds to step S26, the driving force priority mode flag is set to "0", and then the process proceeds to step S22. If the state with the small TH opening is not continuous for a certain period of time, the process proceeds to step S22.
[0053]
In step S27, the flag of the driving force priority mode is set to "1", and the process proceeds to step S22.
[0054]
On the other hand, in step S30 of the flowchart for determining the engine brake mode shown in FIG. 8, it is determined whether the current vehicle speed is high. If the vehicle speed is high, the process proceeds to step S37, and the engine brake mode flag is set to "0". The brake timer is set and the flow ends.
[0055]
If the current vehicle speed is not the high vehicle speed, the process proceeds to step S31, and it is determined whether the current vehicle speed is the low vehicle speed. If the current vehicle speed is the low vehicle speed, the flow ends through step S37. Then, it is determined whether the brake SW is off.
[0056]
If the brake SW is off, the flow ends through step S37. If the brake SW is on, the flow proceeds to step S33.
[0057]
In step S33, it is determined whether the deceleration is excessive. If it is excessive, the flow ends through step S37. If it is not excessive, the process proceeds to step S34, and it is determined whether the deceleration is not large.
[0058]
If the deceleration is not large, the flow ends through step S37. If the deceleration is large, the flow proceeds to step S35 to determine whether or not the engine brake timer has not been set. The mode flag is set to "1", the engine brake timer is set, and the flow ends. If the engine brake timer is set, the flow ends.
[0059]
After the determination of the busy shift prevention mode, the driving force priority mode, and the engine brake mode is performed as described above, the shift mode is selected based on a shift mode selection table shown in Table 1 stored in advance.
[0060]
[Table 1]
That is, when the TH opening speed is high and the vehicle speed is high, the flag of the driving force priority mode is "1" in step S27 of the flowchart of FIG. 7, the busy shift prevention mode flag is "0" in step S24, and the engine brake mode flag is Since each is set to "0", the mode switching means 8 selects the driving force priority mode from the above-mentioned speed change mode selection table and outputs it to the speed change command means 9, so that the speed change command means 9 has the driving force shown in FIG. The gear position is determined based on the priority mode shift pattern, and the automatic transmission 10 is controlled.
[0061]
As a result, a driving state in which the driving force is prioritized can be obtained.
[0062]
When the acceleration / deceleration is small during high-speed running, both the flag of the busy shift prevention mode and the flag of the engine brake mode are set to "0" in step S15 of the flowchart shown in FIG. If the small opening degree continues for a certain period of time, the driving force priority mode flag is set to "0" in step S26 in FIG. 7, and the mode switching means 8 switches the normal traveling mode from the gear change mode selection table. In order to select and output to the shift command means 9, the shift command means 9 determines the gear position according to the normal running mode shift pattern shown in FIG.
[0063]
As a result, a fuel-efficient and comfortable driving situation can be obtained.
[0064]
On the other hand, if sudden acceleration or deceleration of the vehicle is performed while traveling in the normal traveling mode, if the engine load operation speed exceeds a predetermined value in the negative direction, if the deceleration of the vehicle exceeds a predetermined value for a predetermined time, Since the busy shift prevention mode flag is set to "1" according to the flowchart shown in FIG. 6, the mode switching means 8 selects the busy shift prevention mode from the shift mode selection table.
[0065]
The shift pattern in the busy shift prevention mode is different from the normal traveling mode shift pattern shown in FIG. 2 in that the upshift line (solid line) is expanded toward the high speed side and the downshift line (dashed line) is expanded toward the low speed side. The shift command means 9 determines the gear position and controls the automatic transmission 10 according to this shift pattern, so that the downshift when the accelerator is on and the upshift when the accelerator is off are not performed. The comfort can be prevented from being impaired.
[0066]
In addition, the state where the engine load change speed detected by the engine load change speed detecting means 1, the deceleration of the vehicle detected by the vehicle speed detecting means 3, and the acceleration / deceleration detected by the acceleration / deceleration detecting means 4 are within a predetermined value. When the predetermined time or more has elapsed, the mode is switched from the busy shift prevention mode to the normal traveling mode, so that traveling in the normal traveling mode is enabled again.
[0067]
On the other hand, if the deceleration due to the brake exceeds a predetermined value for a certain period of time while traveling in the normal traveling mode or the driving force priority mode, it is determined whether or not the engine brake timer is set in step S35 of the flowchart shown in FIG. If not set, the engine brake mode flag is set to "1" in step S36, and at the same time, the engine brake timer is set.
[0068]
As a result, the mode switching means 8 selects the engine brake mode from the shift mode selection table and outputs it to the shift command means 9, so that the shift command means 9 determines the gear position according to the engine brake mode shift pattern shown in FIG. By controlling the transmission 10, an engine brake state can be obtained.
[0069]
When the engine brake mode is released, the mode is switched to the busy shift prevention mode, and the busy shift is prevented.
[0070]
【The invention's effect】
As described in detail above, the present invention detects sudden acceleration / deceleration of a running vehicle, and in the case of sudden acceleration / deceleration, shifts the shift up line of the shift pattern to a higher speed side and the shift down line to a lower speed side. The shift mode is switched to the busy shift prevention mode, and the gear position of the automatic transmission is determined based on the shift pattern. It is greatly improved.
Further, switching from the busy shift prevention mode to the normal traveling mode and switching from the driving force priority mode to the busy shift prevention mode or the normal traveling mode can be smoothly performed according to the traveling condition of the vehicle.
[0071]
Furthermore, when the vehicle is suddenly decelerated using the brakes, the mode is switched to the engine brake mode and the engine brake is effectively applied, so that the vehicle can be safely decelerated. Since the mode is switched to the shift prevention mode, upshifts and downshifts at the time of sudden acceleration are prevented, thereby improving riding comfort at the time of sudden acceleration.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a shift control device for an automatic transmission according to an embodiment of the present invention.
FIG. 2 is a diagram showing a normal traveling mode shift pattern used by a shift control device for an automatic transmission according to an embodiment of the present invention to determine a gear position.
FIG. 3 is a diagram showing a driving force priority mode shift pattern used by a shift control device for an automatic transmission according to an embodiment of the present invention to determine a gear position.
FIG. 4 is a diagram showing a busy shift prevention mode shift pattern used when the shift control device of the automatic transmission according to the embodiment of the present invention determines a gear position.
FIG. 5 is a diagram showing an engine brake mode shift pattern used when the shift control device for the automatic transmission according to the embodiment of the present invention determines a gear position.
FIG. 6 is a flowchart showing an operation when the shift control device of the automatic transmission according to the embodiment of the present invention determines the busy shift prevention mode.
FIG. 7 is a flowchart showing an operation when the transmission control device for the automatic transmission according to the embodiment of the present invention determines the driving force priority mode.
FIG. 8 is a flowchart showing an operation when the shift control device of the automatic transmission according to the embodiment of the present invention determines the engine brake mode.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Engine load change speed detecting means 2 Engine load detecting means 3 Vehicle speed detecting means 4 Acceleration / deceleration detecting means 5 Brake operation detecting means 6 Controller body 7 Running condition detecting means 8 Mode switching means 9 Shift command means 10 Automatic transmission ]

Claims (7)

An engine load detecting means for detecting an engine load; an engine load changing speed detecting means for detecting a changing speed of the engine load detected by the engine load detecting means; a vehicle speed detecting means for detecting a vehicle speed; Acceleration / deceleration detection means for detecting, brake operation detection means for detecting whether or not the brake is operated, and running conditions detected from engine load, change speed of engine load, vehicle speed, acceleration / deceleration of the vehicle, and presence or absence of brake operation Traveling state detecting means, a mode switching means for selecting a normal traveling mode or a busy shift prevention mode according to the traveling state outputted from the traveling state detecting means, an engine load outputted from the engine load detecting means, and a vehicle speed detection. The gear speed is determined from the vehicle speed output from the gearshift means and the speed change mode output from the mode switching means. Equipped with shift command means for controlling the automatic transmission, and detects whether the vehicle is rapidly accelerating or decelerating from the driving situation output from the traveling situation detecting means, or at high speed. Automatic switching characterized by switching to a busy shift prevention mode in which a gap between a shift up line and a shift down line of a shift pattern is appropriately widened from a normal traveling mode, and switching to a normal traveling mode for high-speed traveling or small acceleration / deceleration. Transmission control device for transmission. When the engine load change speed detected by the engine load change speed detecting means exceeds a predetermined value in the negative direction, or when a predetermined time has elapsed since the deceleration of the vehicle detected by the acceleration / deceleration detecting means exceeds a predetermined value. Switching from the normal running mode to the busy shift prevention mode, the engine load change speed detected by the engine load change speed detecting means, the speed of the vehicle detected by the vehicle speed detecting means, and the vehicle speed detected by the acceleration / deceleration detecting means. 2. The shift control device for an automatic transmission according to claim 1, wherein the switching from the busy shift prevention mode to the normal running mode is performed when the acceleration / deceleration is within a predetermined value for a predetermined time or more. . When the driving force priority mode selected by the mode switching means is released, the shift command means is configured to output the engine load change speed detected by the engine load change speed detecting means, the vehicle speed detected by the vehicle speed detecting means, or the vehicle speed detecting means. 2. The shift control device for an automatic transmission according to claim 1, wherein the mode is switched to a busy shift prevention mode or a normal running mode in accordance with the acceleration / deceleration of the vehicle detected by the acceleration / deceleration detecting means. When the deceleration of the vehicle due to the brake exceeds a predetermined value for a certain period of time, the engine shifts to the engine brake mode in which the engine brake is applied more than in the normal driving mode, and after the engine brake mode ends, the mode is switched to the busy shift prevention mode. The shift control device for an automatic transmission according to claim 1, wherein: 2. The automatic transmission according to claim 1, wherein in the busy shift prevention mode, the upshift line of the shift pattern is extended to a higher speed side than the normal traveling mode, and the downshift line is made similar to the normal traveling mode. Control device. The shift instructing means switches to a busy shift prevention mode in which the shift down line of the shift pattern is expanded to the deceleration side when the vehicle is suddenly decelerated in the driving force priority mode. The shift control device for an automatic transmission according to claim 1, wherein the shift control device is configured to maintain the shift. The shift instructing means switches to a busy shift prevention mode in which the shift down line of the shift pattern is extended to a deceleration side when the vehicle is suddenly decelerated during traveling in a low speed region in the engine brake mode. The shift control device for an automatic transmission according to claim 1, wherein the engine brake mode is maintained when the vehicle is suddenly decelerated during traveling.

Images