JP2014152842A - Method and system for controlling automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To essentially achieve a quick automatic return from a direct mode to an automatic shift mode without imparting discomfort to a driver and causing deterioration of operability during run in a high speed.SOLUTION: It is determined whether or not a direct mode in which shifting is manually performed temporarily is executed by operation of a shift switch (step S1). In the case in which the direct mode is executed, when a predetermined time Tpasses after a return request condition of requesting automatic return from the direct mode to an automatic shift mode is satisfied, the direct mode is automatically returned to the automatic shift mode (step S10). But when a vehicle runs in a rapid acceleration condition, the automatic return from the direct mode to the automatic shift mode is prohibited, and the direct mode is continued (step S9). As a vehicle speed is higher, threshold values Pa, Pb for determination of rapid acceleration are set lower (step S7).

Description

  The present invention relates to control of an automatic transmission for a vehicle having a manual transmission function, and belongs to the field of vehicle transmission technology.

  2. Description of the Related Art In recent years, as an automatic transmission for a vehicle, an automatic transmission mode that automatically switches a gear position based on a predetermined gear map according to a traveling state, and a manual transmission mode that switches a gear position by a driver's manual operation are provided. Have been put to practical use. In manual shift mode, the gear position can be selected at the driver's will. For example, if you want to apply engine braking while driving on a highway, or if you want to accelerate quickly to pass, manual shift mode By using, more comfortable driving can be realized.

  The continuously variable transmission (CVT) also has an automatic transmission mode in which the transmission ratio is automatically changed according to the running state and a manual transmission mode in which the transmission ratio is switched stepwise by a manual operation by the driver. Things are conventionally known. In a vehicle equipped with this type of continuously variable transmission, a plurality of shift speeds are set in advance for the manual shift mode. Hereinafter, for convenience of explanation, the term “automatic transmission” refers not only to a stepped automatic transmission having a mechanism for switching a gear ratio in stages, but also to a continuously variable gear having a mechanism for continuously changing the gear ratio. It is assumed that the automatic transmission is included.

  As the manual shift mode, a manual mode that is executed by selecting a dedicated shift range called, for example, “M range” by operating the shift lever, and the shift lever is provided on the steering wheel or the like independently. There is a direct mode temporarily executed by operating a shift switch (upshift switch or downshift switch).

  The direct mode is mainly executed to perform rapid acceleration for overtaking or to operate the engine brake. For this reason, the direct mode is usually continued when the direct mode is in a sudden acceleration state or an engine brake operating state. Even during cornering, the direct mode may be continued because there is a high possibility that acceleration will be performed immediately after. When the predetermined traveling state that requires the continuation of the direct mode is completed, the automatic transmission mode is automatically restored when a predetermined time has elapsed from the end point.

  In addition, when the direct mode is started due to an erroneous operation of the shift switch, when the rapid acceleration state or the engine brake operation state is not immediately started even if the direct mode is started, a predetermined time has elapsed after the shift switch is operated. The automatic transmission mode is automatically restored. A configuration for returning to the automatic transmission mode after a predetermined time has elapsed since the start of the direct mode is disclosed in, for example, Patent Document 1.

  Conditions for requesting automatic return from the direct mode to the automatic transmission mode as described above (for example, that the rapid acceleration state ends, the engine brake operation state or the cornering traveling state ends, or other traveling states ( The predetermined time from when the shift switch operation (shift switch operation with a possibility of erroneous operation) in the steady traveling state) is established to when the automatic return is actually performed is as short as about 3 seconds, for example. Set to time. Accordingly, when the direct mode is executed by the downshift operation, the fuel consumption can be improved by promptly returning to the automatic transmission mode and prompting the upshift according to the traveling state. In addition, when the direct mode is started due to an erroneous operation, the driver's uncomfortable feeling can be reduced by quickly returning to the automatic transmission mode.

Japanese Patent Laid-Open No. 11-257485

  However, regarding the automatic return from the direct mode to the automatic shift mode, the inventor of the present application always requires a quick automatic return from the viewpoint of improving fuel efficiency during driving on a general road where a relatively low shift speed is used. Thus, the present inventors have found that during highway driving with high operability and safety requirements, it is likely that a driving situation that requires the direct mode to continue for a relatively long time is likely to occur.

  An example of such a driving situation on a highway is shown in FIG. FIG. 10A shows that the direct mode is executed by the driver operating the downshift switch so that the vehicle A traveling on the overtaking lane of the expressway overtakes the vehicles B and C traveling on the traveling lane. When the vehicle B is about to accelerate rapidly, the vehicle B changes the lane to the overtaking lane in order to overtake the vehicle C in front of it. In such a situation, as shown in FIG. 10B, the vehicle A cannot be accelerated because the front is blocked by the vehicle B, and follows the rear of the vehicle B in a non-accelerated state until the vehicle can be accelerated. While waiting. If the shift mode of the vehicle A is automatically returned to the automatic shift mode against the driver's will during this standby period, it may be automatically upshifted according to the shift diagram. Therefore, as shown in FIG. 10C, even when the vehicle A can suddenly accelerate by returning to the driving lane, the vehicle A may not obtain a desired acceleration force.

  As another example, while driving on a highway, when the direct mode is executed by operating the downshift switch to perform rapid acceleration for overtaking or activate the engine brake, these sudden accelerations After the running state and the engine brake operation state are finished, it is assumed that a sudden acceleration run and engine brake operation are required again within a few seconds. In this case, if the direct mode is automatically returned to the automatic shift mode due to the end of the immediately preceding rapid acceleration running state or the engine brake operating state, an upshift against the driver's will is performed, and the desired mode is achieved. Acceleration force and braking force may not be obtained.

  Therefore, if it is controlled to return from the direct mode to the automatic transmission mode in a uniformly short time as in the past, the early return to the automatic transmission mode may give the driver a sense of discomfort during high-speed driving depending on the driving conditions. The operability may deteriorate due to the need to re-operate the shift switch.

  Therefore, the present invention basically makes a quick automatic return from the direct mode to the automatic transmission mode, and causes the driver to feel uncomfortable or deteriorate the operability during the high speed driving. The problem is to prevent this.

  In order to solve the above-mentioned problems, the control method and control device for an automatic transmission according to the present invention are configured as follows.

First, the invention according to claim 1 of the present application is
When the shift lever is in the drive range position, either the automatic shift mode that automatically shifts according to the running state of the vehicle, or the direct mode that temporarily shifts manually by operating the shift switch A control method for an automatic transmission that is selectable and automatically returns to an automatic transmission mode when a predetermined time has elapsed from when a predetermined return request condition is satisfied when the direct mode is selected,
A mode determination step for determining whether or not the direct mode has been executed;
A vehicle speed detection process for detecting the vehicle speed in the direct mode;
An accelerator opening detection step for detecting the accelerator opening in the direct mode;
A rapid acceleration determination step of determining a rapid acceleration state when the accelerator opening detected in the accelerator opening detection step is greater than or equal to a predetermined threshold, and determining a non-rapid acceleration state when less than the predetermined threshold;
A return prohibiting step for prohibiting automatic return to the automatic shift mode when it is determined in the sudden acceleration determination step that the vehicle is in a sudden acceleration state;
In the rapid acceleration determination step, the predetermined threshold is lowered as the vehicle speed detected in the vehicle speed detection step is higher.

The invention according to claim 2 of the present application is the invention according to claim 1,
In the sudden acceleration determination step, as the predetermined threshold, the first threshold is used when determining from the non-rapid acceleration state to the rapid acceleration state, and when determining from the sudden acceleration state to the non-rapid acceleration state, A second threshold value lower than the first threshold value is used, and at least one of the first threshold value and the second threshold value is lowered as the vehicle speed detected in the vehicle speed detection step is higher.

Furthermore, the invention according to claim 3 of the present application is the invention according to claim 2,
In the rapid acceleration determination step, both the first threshold value and the second threshold value are lowered as the vehicle speed detected in the vehicle speed detection step is higher.

The invention according to claim 4
When the shift lever is in the drive range position, either the automatic shift mode that automatically shifts according to the running state of the vehicle, or the direct mode that temporarily shifts manually by operating the shift switch A control device for an automatic transmission that can be selected,
A vehicle speed sensor for detecting the vehicle speed;
An accelerator opening sensor for detecting the accelerator opening;
When the accelerator opening detected by the accelerator opening sensor is equal to or greater than a predetermined threshold, it is determined that the vehicle is in a rapid acceleration state, and when the accelerator opening is less than the predetermined threshold, the non-rapid acceleration state is determined. A controller that automatically returns to the automatic shift mode when a predetermined time has elapsed from when the return request condition is satisfied, and prohibits automatic return to the automatic shift mode in a sudden acceleration state,
The controller is characterized in that the predetermined threshold is lowered as the vehicle speed detected by the vehicle speed sensor in the direct mode is higher.

Furthermore, the invention described in claim 5
When the shift lever is in the drive range position, either the automatic shift mode that automatically shifts according to the running state of the vehicle, or the direct mode that temporarily shifts manually by operating the shift switch A control device for an automatic transmission that is selectable and automatically returns to an automatic transmission mode when a predetermined time has elapsed from when a predetermined return request condition is satisfied when the direct mode is selected,
Mode determination means for determining whether or not the direct mode has been executed;
Vehicle speed detection means for detecting the vehicle speed in direct mode;
An accelerator opening detecting means for detecting the accelerator opening in the direct mode;
A rapid acceleration determining means for determining that the accelerator opening is detected when the accelerator opening detected by the accelerator opening detecting means is equal to or greater than a predetermined threshold, and that the accelerator opening is less than the predetermined threshold;
A return prohibiting means for prohibiting an automatic return to the automatic shift mode when the sudden acceleration determining means determines that it is in a sudden acceleration state;
Setting means for setting the predetermined threshold value to be lower as the vehicle speed detected by the vehicle speed detection means is higher.

  With the above configuration, according to the invention of each claim of the present application, the following effects can be obtained.

  First, according to the control method for an automatic transmission according to the first aspect of the present invention, in the direct mode, when the vehicle is in the rapid acceleration state, automatic return to the automatic transmission mode is prohibited, and whether or not the vehicle is in the rapid acceleration state. The threshold value of the accelerator opening used for such determination is set lower as the vehicle speed is higher.

  For this reason, during high-speed traveling, it is easy to determine that the vehicle is in a sudden acceleration state, and early automatic return to the automatic transmission mode is suppressed. Therefore, when driving at high speeds, where the direct mode tends to be required for a relatively long period of time, the automatic return to the automatic shift mode is executed at an early stage contrary to the intention, giving the driver a sense of discomfort or shifting. It is possible to prevent the operability from being deteriorated by requiring the switch to be operated again.

  Specifically, for example, when executing direct mode by downshifting a shift switch while driving on a highway, and suddenly accelerating after a waiting time of several seconds, the driver will On the other hand, since the automatic return to the automatic shift mode is prevented, the driver can accelerate at a desired shift stage without feeling uncomfortable without re-operating the shift switch. Also, for example, when the direct mode is being executed while driving on a highway, when the rapid acceleration traveling state or the engine braking operation state ends, the rapid acceleration traveling or the engine braking operation is performed again after an interval of several seconds. In this situation, the driver is prevented from automatically returning to the automatic shift mode against the driver's will during the interval, so that the driver feels uncomfortable at the desired shift stage without operating the shift switch again. Without re-acceleration or engine brake reactivation.

  On the other hand, when the vehicle is traveling at a relatively low speed, it is automatically returned to the automatic transmission mode immediately after the return request condition is satisfied, thereby realizing smooth driving at a gear position corresponding to the vehicle speed and the accelerator opening. be able to. In particular, when the direct mode is executed by downshifting the shift switch while driving on a general road where a relatively low gear stage is used, the vehicle speed and the accelerator opening can be reduced by quick automatic return to the automatic shift mode. Since the corresponding upshift is promptly promoted, fuel consumption can be improved.

  According to the second aspect of the present invention, the threshold value of the accelerator opening is greater than the first threshold value used for determination when changing from the non-rapid acceleration state to the rapid acceleration state. Since the second threshold value used for determination when changing to the non-rapid acceleration state is low, it is determined that the acceleration state is suddenly increased by increasing the accelerator opening, and then sudden acceleration is immediately performed by a slight decrease in accelerator opening. Unstable control in which the end of the state is determined can be prevented. Further, at least one of the first threshold value and the second threshold value is set to be lower as the vehicle speed is higher as described above, whereby the effect of the invention according to claim 1 is suitably achieved.

  Furthermore, if the invention according to claim 3 is applied to the invention according to claim 2, both the first threshold value and the second threshold value are set to be lower as the vehicle speed is higher. The effect of the invention according to claim 1 can be reliably achieved in any of the descending operations.

  According to the control apparatus for an automatic transmission according to the fourth aspect of the present invention, the automatic return to the automatic shift mode is prohibited when the controller is under the rapid acceleration state in the direct mode under the control of the controller. Since the threshold value of the accelerator opening used for determining whether or not the vehicle is in a state is set lower as the vehicle speed is higher, the same effect as that of the first aspect of the invention can be obtained.

  Further, according to the control device for an automatic transmission according to the fifth aspect of the present invention, in the direct mode, when the vehicle is in the rapid acceleration state, automatic return to the automatic transmission mode is prohibited, and whether or not the vehicle is in the rapid acceleration state. Since the threshold value of the accelerator opening used for the determination is set to be lower as the vehicle speed is higher, the same effect as that of the first aspect of the invention can be obtained.

It is the schematic of the motor vehicle carrying the automatic transmission with which embodiment of this invention is applied. It is a perspective view which shows a shift lever, and a top view which shows the operation position. It is the top view and front view which show arrangement | positioning of a steering down switch and a steering up switch. It is a figure which shows the structure of a meter unit. It is a figure which shows the lighting pattern of the principal part of the indicator for automatic transmissions in the meter unit. 1 is a system diagram of a control device for an automatic transmission according to an embodiment of the present invention. It is a figure which shows an example of the map used for sudden acceleration determination. It is a flowchart which shows the flow of the example of control performed for the automatic return from direct mode to automatic transmission mode. FIG. 9 is a time chart showing an example of an operation when the count of the return timer elapses for a predetermined time in the sudden acceleration state and then enters the non-rapid acceleration state in the control example shown in FIG. 8. It is a figure which shows the driving | running | working condition which cannot accelerate immediately after starting the direct mode for the purpose of carrying out rapid acceleration for overtaking while driving on a highway.

  Hereinafter, embodiments of a control method and a control apparatus for an automatic transmission according to the present invention will be described.

  FIG. 1 is a schematic view of an automobile equipped with an automatic transmission to which an embodiment of the present invention is applied. A power unit formed by coupling the engine 1 and the automatic transmission 2 via a torque converter 10 is mounted on the front portion of the automobile. Further, a shift lever 3 for switching the range of the automatic transmission 2 is disposed on the side of the driver's seat in the vehicle.

  The automatic transmission 2 can be switched between an automatic transmission mode that automatically changes gears according to the traveling state of the automobile and a manual transmission mode that changes gears by a driver's shift operation. Further, in the present embodiment, the manual shift mode is canceled when a predetermined condition is satisfied from a manual mode that is continuously executed until a change operation to the automatic shift mode is performed, and a predetermined operation that will be described later. And direct mode that is temporarily executed.

  A steering wheel 4 is disposed in front of the driver's seat inside the vehicle, and a meter unit 5 is disposed on the instrument panel in front of the steering wheel 4. Further, an accelerator pedal 6 is disposed at the foot of the driver's seat.

  As shown in FIG. 2A, the shift lever 3 is operated along a series of operation paths 32 provided in the guide member 31. As shown in FIG. 2B, on the operation path 32, a parking range (P range) position, a reverse range (R range) position, a neutral range (N range) position, and a drive range (D range) position. Is provided. When the shift lever 3 is operated to the D range position, the shift mode of the automatic transmission 2 is set to the automatic shift mode.

  Further, a manual range (M range) position 33 is provided on the side of the D range position, and when the shift lever 3 is operated from the D range position to the M range position 33, the shift of the automatic transmission 2 is performed. The mode can be switched to the manual mode.

  This M-range position 33 has a long operation area in the front and rear, and when the shift lever 3 is operated forward (in the direction of arrow A shown in FIG. 2B) from the central neutral position, a downshift switch (hereinafter, “ If the shift lever down switch 34) is turned on and the gear position of the automatic transmission 2 is shifted down by one step and operated backward (in the direction of arrow B shown in FIG. 2B), the upshift switch ( Hereinafter, it is referred to as “shift lever up switch”.) 35 is turned ON, and the gear position is shifted up by one step.After the operation, it returns to the neutral position to prepare for the next operation. Yes.

  As shown in FIGS. 3 (a) and 3 (b), the steering wheel 4 includes a center paddle portion 41, three spokes 42, 43, 44 extending in a T-shape from the paddle portion 41, It is comprised with the wheel part 45 supported by these spokes. A pair of left and right downshift switches (hereinafter referred to as a “steering down switch”) is positioned in front of the left and right spokes 42 and 43 on the front side, that is, in the vicinity of the position where the thumbs of the left and right hands of the driver holding the wheel portion 45 are located. 46, 46 are also provided, and a finger other than the thumbs of the left and right hands of the driver who holds the predetermined portion of the paddle portion 41 on the back side of the spokes 42, 43, that is, the wheel portion 45 is provided. A pair of left and right upshift switches (hereinafter, also referred to as “steering up switches”) 47 and 47 are provided in the vicinity of the portion where is located.

  The steering down switches 46 and 46 and the steering up switches 47 and 47 have the following two functions. The first function is to downshift the shift stage instead of the shift lever down switch 34 and the shift lever up switch 35 when the shift lever 3 is operated to the M range position and the manual mode is selected. The second function is an upshift function. When the shift lever 3 is operated to the D range position and the automatic transmission mode is selected, either the steering down switch 46, 46 or the steering up switch 47, 47 is used. One of them is a function of switching the shift mode from the automatic shift mode to the direct mode and downshifting or upshifting the gear by turning on one of them.

  In either case, if either one (or both) of the pair of steering down switches 46, 46 is pushed down in the direction of the arrow A ′ shown in FIG. 2 shift stage is shifted down by one stage, and if either one (or both) of the pair of steering up switches 47, 47 is pulled toward the front as shown by arrow B ', the switch 47 is turned ON. The gear position is upshifted by one step.

  As shown in FIG. 4, the meter unit 5 includes a vehicle speedometer 51 in the center, an engine tachometer 52 in the left area, a water temperature gauge 53 in the right area, a fuel gauge 54, and indicators indicating the state of the automatic transmission 2. 55 is arranged.

  The indicator 55 includes a P range indicator 55a, an R range indicator 55b, an N range indicator 55c, and a D range indicator 55d that indicate the range selected by operating the shift lever 3, and further includes a D range indicator. Adjacent to the display device 55d, a direct mode display device 55e indicating the character “D” and a manual mode display device 55f indicating the character “M” are provided. Among these indicators, the D range indicator 55d is composed of a segment type indicator.

  Here, display modes of the D range display 55d, the direct mode display 55e, and the manual mode display 55f will be described.

  First, as shown in FIG. 5A, in the automatic transmission mode in which the shift lever 3 is in the D range position, the direct mode indicator 55e and the manual mode indicator 55f are turned off, and the D range indicator 55d is “D”. The character of is displayed.

  As shown in FIG. 5B, in the manual mode in which the shift lever 3 is at the M range position, the direct mode indicator 55e is turned off, the manual mode indicator 55f is turned on, and the D range indicator 55d is turned on. A number indicating the gear position at that time is displayed.

  Then, as shown in FIG. 5C, one of the steering down switches 46 and 46 or the steering up switches 47 and 47 is turned on while the shift lever 3 is operated to the D range position. In the direct mode set by the above, the direct mode indicator 55e and the manual mode indicator 55f are turned on, and the D range indicator 55d displays a number indicating the gear position at that time.

  Next, the controller 100 that controls the automatic transmission 2 and the indicator 55 will be described.

  As shown in FIG. 6, the controller 100 includes a signal from the vehicle speed sensor 101 that detects the vehicle speed, a signal from the accelerator opening sensor 102 that detects the accelerator opening (the amount of depression of the accelerator pedal 6), and a shift lever. The signal from the shift position sensor 103 that detects the operation position 3 is input.

  Further, the controller 100 receives signals from the shift lever down switch 34 and the shift lever up switch 35 for the control in the manual mode, and the steering down for the control in the manual mode and the direct mode. Signals from the switch 46 and the steering up switch 47 are input.

  Further, the controller 100 is provided with a storage unit 110 that stores various information used for shift control of the automatic transmission 2 and display control of the indicator 55 in the meter unit 5.

  The controller 100 sets a gear position based on the signals from the sensors and switches and various information stored in the storage unit 110, and controls the automatic transmission 2 so as to realize the gear position. A signal is output, and a display control signal for controlling the display state of each of the indicators 55a to 55f is output to the indicator 55.

  By the way, since the direct mode is temporarily executed in the middle of the automatic transmission mode, in the direct mode, the controller 100 requests a predetermined return request for automatically returning from the direct mode to the automatic transmission mode. When the condition is satisfied, the count by the return timer is started. When the count is counted for a predetermined time by the return timer, control is performed so as to automatically return to the automatic transmission mode.

  The return request condition is not particularly limited, but in the present embodiment, the following three conditions are set as the return request condition.

  The first return request condition is that an operation of the steering down switch 46 or the steering up switch 47 is detected when the accelerator pedal 6 is depressed in a non-rapid acceleration state. This condition was set assuming a situation in which the direct mode is started in a driving state that is neither a sudden acceleration state, an engine brake operating state, or a cornering driving state (hereinafter also referred to as “steady driving state”). It is a condition. This assumed situation may be a situation where the direct mode is executed against the driver's will due to an erroneous operation of the steering down switch 46 or the steering up switch 47. Even if this assumed situation is a situation in which the direct mode is executed by the driver's intention, depending on the running situation after the start of the direct mode, sudden acceleration or engine brake operation may not be performed. As described above, when the direct mode is started due to an erroneous operation, or when sudden acceleration or engine braking cannot be performed after the direct mode is started, when a predetermined time elapses after the first return request condition is satisfied. Therefore, after the automatic return, smooth steady running can be realized at a gear position corresponding to the running state.

  The second return request condition is that a change from the sudden acceleration state to the non-rapid acceleration state is detected during execution of the direct mode. This condition is set under the assumption that the direct mode is executed by the operation of the steering down switch 46, the sudden acceleration traveling is performed in a state where the downshift is performed by one or more steps, and the sudden acceleration traveling ends. It is. Such an assumed situation is a situation in which the rapid acceleration traveling, which is the purpose of executing the direct mode, ends, and the continuation of the direct mode may not be necessary any more. Under such circumstances, smooth steady running is possible by quickly returning to the automatic transmission mode after the second return request condition is satisfied.

  The third return request condition is that the start of depression of the accelerator pedal 6 is detected during execution of the direct mode. In this condition, the direct mode is executed by the operation of the steering down switch 46, and the engine brake is operated or the cornering travel is performed in a state where the downshift is performed by one or more stages, and the engine brake operation state or the cornering travel state is finished. This is a condition that is set assuming the situation. Such an assumed situation is that when the accelerator pedal 6 is started to be depressed, the engine brake operation or cornering traveling, which is the purpose of the direct mode execution, is finished, and there is a possibility that further continuation of the direct mode is not necessary. It is. In such a situation, smooth steady running is possible by quickly returning to the automatic transmission mode after the third return request condition is satisfied.

  In the present embodiment, the above three return request conditions are set, but only one or two of these three conditions may be set as the return request conditions. Good. Further, conditions other than those described above may be set as further return request conditions.

  As described above, in order to determine whether the first or second return request condition is satisfied, it is necessary to perform a rapid acceleration determination that determines whether the traveling state is the sudden acceleration state or the non-rapid acceleration state. . For this sudden acceleration determination, for example, a map shown in FIG. 7 stored in the storage unit 110 is used. In the map shown in FIG. 7, regardless of the vehicle speed, the region where the accelerator opening is equal to or greater than the predetermined threshold is the “rapid acceleration region”, and the region less than the predetermined threshold is the “non-rapid acceleration region”. In the acceleration determination, the traveling state when the accelerator opening belongs to the rapid acceleration region is determined as the “rapid acceleration state”, and the traveling state when it belongs to the non-rapid acceleration region is determined as the “non-rapid acceleration state”.

  In addition, as the threshold value of the accelerator opening in the map of FIG. 7, a first threshold value Pa and a second threshold value Pb lower than the first threshold value Pa are set. The first threshold value Pa is used for the determination when the state changes to the state, and the second threshold value Pb is used for the determination when the state changes from the sudden acceleration state to the non-rapid acceleration state. Thus, by setting the second threshold value Pb lower than the first threshold value Pa, for example, the accelerator opening slightly rises from the opening degree of the non-rapid acceleration region and immediately after the threshold value is exceeded, to the original opening degree. When the vehicle descends, it is possible to prevent unstable control from being determined to have returned to the non-rapid acceleration state immediately after it has been determined that the sudden acceleration state has been reached.

  As shown in FIG. 7, both the first threshold value Pa and the second threshold value Pb are set in two stages according to the vehicle speed, and are set to be lower as the vehicle speed is higher. By setting the threshold values Pa and Pb in this way, in the rapid acceleration determination, it is easy to determine the sudden acceleration state in the high vehicle speed region higher than the first speed Va.

  Specifically, when the first threshold value Pa is equal to or higher than the first speed Va, the first opening degree P1 is set. When the first threshold value Pa is less than the second speed Vb that is lower than the first speed Va, the first threshold value Pa is set. The second opening P2 is set higher than the opening P1. On the other hand, when the second threshold value Pb is equal to or higher than the first speed Va, the fourth opening degree P3 is higher than the third opening degree P3. The degree P4 is set.

  Specifically, for example, the first speed Va is set to 100 km / h, the second speed Vb is set to 80 km / h, the first opening P1 is 45%, and the second opening P2 is 60. %, The third opening P3 is set to 35%, and the fourth opening P4 is set to 50%.

  In the map of FIG. 7, when the second speed Vb is equal to or higher than the first speed Va, the first threshold value Pa is equal to or higher than the first opening degree P1 and the second opening degree P2 and is proportional to the vehicle speed. Thus, the second threshold value Pb is set to a value that is not less than the third opening degree P3 and not more than the fourth opening degree P4 and decreases in proportion to the vehicle speed. By setting in this way, in the vehicle speed region of the second speed Vb or more and the first speed Va or less, the sudden acceleration determination thresholds Pa and Pb are avoided from changing suddenly at a specific vehicle speed. A sense of incongruity can be prevented.

  However, the map used for the rapid acceleration determination is not limited to that shown in FIG. For example, in the map shown in FIG. 7, the first threshold value Pa and the second threshold value Pb are both set to be lower as the vehicle speed is higher, but the first threshold value Pa or the second threshold value Pb is set. One or both of these settings are set in three or more stages so as to decrease as the vehicle speed increases, or set so as to decrease proportionally as the vehicle speed increases, or one of the threshold values Pa and Pb is set to a constant value. May be.

  Hereinafter, control executed by the controller 100 for automatic return from the direct mode to the automatic transmission mode (hereinafter referred to as “automatic return control”) will be described.

  An example of the flow of each process in the automatic return control will be described with reference to the flowchart shown in FIG.

  The automatic return control shown in FIG. 8 is executed when the shift lever 3 is operated to the D range position. When the automatic return control is executed, it is first determined in step S1 whether or not the direct mode has been executed. Specifically, when any of the switches 46 and 47 is operated based on whether or not the steering down switch 46 and the steering up switch 47 are operated in a state where the shift lever 3 is operated to the D range position, It is determined that the mode has been executed. Only when the direct mode is being executed as a result of the determination in step S1, the processes in and after step S2 are executed.

In step S2, it is determined whether or not the count by the return timer is started. If the count is not yet started, the process proceeds to step S3. If the count is in progress, the process proceeds to step S5 and the set time T ₀ of the return timer is set. It is determined whether or not it has elapsed.

  In addition, a return timer is prepared for each return request condition described above, and if the return timer count is canceled even after any of the return timer counts is started, In step S2, it is determined that the count is not yet started. In addition, the count cancellation of the return timer is executed when a predetermined stop condition (for example, the release of the direct mode or the travel state requesting the continuation of the direct mode) is established during the count. . Examples of the running state that requires continuation of the direct mode include a sudden acceleration state, an engine brake operating state, and a cornering running state.

  In step S3, it is determined whether or not a count start condition for starting the count of the return timer is satisfied. When the count start condition is satisfied, the count of the return timer is started (step S4).

  The count start condition is equal to the above-described return request condition. In step S3, it is determined that the count start condition is satisfied when any one of the first to third return request conditions is satisfied. In step S4, the count of the return timer corresponding to the return request condition established at the time of the determination in step S3 among the first to third return request conditions is started.

  In step S3, the determination that the first return request condition is satisfied is made when an operation of the steering down switch 46 or the steering up switch 47 is detected when the accelerator pedal 6 is depressed in the non-rapid acceleration state. In this determination, the determination of the non-rapid acceleration state is made by the rapid acceleration determination based on the map of FIG. 7 described above, and the fact that the accelerator pedal 6 is depressed is indicated by an input signal from the accelerator opening sensor 102. Based on this, it is determined that the accelerator opening is larger than zero. Further, whether or not the steering down switch 46 or the steering up switch 47 is operated is determined based on input signals from these switches 46 and 47.

  In step S3, whether or not the second return request condition is satisfied is determined when a change from the sudden acceleration state to the non-rapid acceleration state (end of the sudden acceleration state) is detected during execution of the direct mode. For this determination, the above-described rapid acceleration determination is used.

  Furthermore, in step S3, the determination that the third return request condition is satisfied is made when the start of depression of the accelerator pedal 6 (engine brake operation state or cornering travel state end) is detected during execution of the direct mode. In this determination, the start of depression of the accelerator pedal 6 is detected when the accelerator opening changes from zero to a positive value based on an input signal from the accelerator opening sensor 102.

When the count of the return timer is started in step S4, the count, unless the cancellation condition is not satisfied, set time T ₀ of the return timer is continued until the elapsed.

In the next step S5, the count of the return timer whether passed a set time T ₀ is determined. Incidentally, the set time T ₀ is not particularly limited, is set to, for example, 3 seconds. Further, the set time T ₀ may be set to be different for each recovery timer. Further, the set time T ₀ may be set at different times in accordance with the vehicle speed, for example, in the low vehicle speed range where the low gear position is used (e.g., vehicle speed range of less than 40 km / h), a shorter time set time T ₀ may be set to.

Is determined in step S5, when the set time T ₀ has elapsed, the detected vehicle speed and the accelerator opening in the next step S6, in the subsequent step S7, in accordance with the vehicle speed detected in step S6, a map shown in FIG. 7 The first threshold value Pa and the second threshold value Pb are set.

  In the subsequent step S8, the above-described rapid acceleration determination is performed based on the threshold values Pa and Pb set in step S7. If it is determined by the sudden acceleration determination in step S8 that the non-rapid acceleration state is set, the direct mode is returned to the automatic transmission mode (step S10), and if it is determined that the rapid acceleration state is set, By the return prohibiting step in step S9, automatic return to the automatic transmission mode is prohibited and the direct mode is continued.

  In step S7, the first threshold value Pa and the second threshold value Pb are set lower as the vehicle speed is higher, particularly in a high vehicle speed region that is equal to or higher than the first speed Va. , It is easy to determine that the vehicle is in a sudden acceleration state.

For example, as shown in FIG. 9, at time t0, when accelerating in a non-rapid acceleration state to start the direct mode by operation of the steering-down switch 46, before the time t2 the set time T ₀ of the return timer elapses When the first threshold value Pa decreases from the second opening degree P2 to the first opening degree P1 when the vehicle speed exceeds the first speed Va at time t1, the rapid acceleration determination based on the map shown in FIG. 8 is determined to be in the rapid acceleration state in step S8). Therefore, in this example, even when time t2 has elapsed, the direct mode is maintained until time t3 when the non-rapid acceleration state is reached.

  As described above, in the high vehicle speed region of the first speed Va or higher, it is easy to determine the sudden acceleration state in the sudden acceleration determination. Therefore, the early automatic return to the automatic transmission mode is performed by the return prohibiting step (step S9 in FIG. 8). Is suppressed. Therefore, when driving at high speed, where the direct mode tends to be required for a relatively long period of time, the automatic return to the automatic shift mode is executed unexpectedly at an early stage, causing the driver to feel uncomfortable, It is possible to prevent the operability from being deteriorated by requiring the down switch 46 to be operated again.

  Specifically, for example, when the direct mode is executed by a downshift operation of the steering down switch 46 while driving on a highway, and when the vehicle accelerates rapidly after a waiting time of several seconds, the driver's Since the automatic return to the automatic shift mode is prevented from being performed unexpectedly, the driver can accelerate the vehicle at a desired shift stage without feeling uncomfortable without operating the steering down switch 46 again.

  Also, for example, when the direct mode is being executed while driving on a highway, when the rapid acceleration traveling state or the engine braking operation state ends, the rapid acceleration traveling or the engine braking operation is performed again after an interval of several seconds. In this situation, it is possible to prevent the driver from automatically returning to the automatic shift mode against the driver's will during the interval, so that the driver can change the desired gear stage without operating the steering down switch 46 again. This makes it possible to re-accelerate or restart the engine brake without a sense of incompatibility.

  On the other hand, in a relatively low vehicle speed region lower than the second speed Vb, it is easy to determine that the vehicle is in a non-rapid acceleration state in the rapid acceleration determination (step S8 in FIG. 8), and thus prompt automatic return to the automatic shift mode is promoted. (Step S8 in FIG. 8). Therefore, particularly when the direct mode is executed by the downshift operation of the steering down switch 46 while driving on a general road where a relatively low gear stage is used, the vehicle speed or Since an upshift according to the accelerator opening is promptly promoted, fuel consumption can be improved.

  While the present invention has been described with reference to the above-described embodiments, the present invention is not limited to the above-described embodiments.

For example, in the above-described embodiment, as shown in FIG. 8, when the return timer counts a predetermined time T ₀ , the vehicle speed and the accelerator opening are detected (step S6), and set based on the vehicle speed at this time. Although the case where the rapid acceleration determination (step S8) is performed using the threshold values Pa and Pb (step S7) that have been performed has been described, in the present invention, a series of processing from step S6 to step S8 is performed during the count of the return timer. Alternatively, it may be performed before the count of the return timer is started, and when it is determined that the acceleration state is sudden, the count of the return timer may not be started.

  In the above-described embodiment, the case where the direct mode is started by the operation of the steering down switch or the steering up switch has been described. However, in the present invention, the direct mode may be started by any operation of the shift switch. For example, the direct mode may be executed by operating a shift switch provided on the instrument panel.

  Furthermore, in the above-described embodiment, the stepped automatic transmission provided with a mechanism for switching the gear ratio stepwise has been described. However, the present invention provides an automatic transmission that can be switched between the manual transmission mode and the automatic transmission mode. If it is a machine, it can be similarly applied to a continuously variable transmission (CVT) provided with a mechanism for continuously changing a gear ratio.

  As described above, according to the present invention, the automatic return to the automatic shift mode from the direct mode is basically performed, while the high speed driving makes the driver feel uncomfortable or the operability is improved. Since it is possible to prevent the deterioration, it may be suitably used in the manufacturing industry of a vehicle equipped with an automatic transmission having functions of an automatic transmission mode and a direct mode.

1 Engine 2 Automatic transmission 3 Shift lever 4 Steering wheel 6 Accelerator pedal 46 Steering down switch (shift switch)
47 Steering up switch (shift switch)
55 Indicator 100 Controller 101 Vehicle speed sensor 102 Accelerator opening sensor 110 Storage unit Pa First threshold Pb Second threshold P1 First opening P2 Second opening P3 Third opening P4 Fourth opening T ₀ set Time (predetermined time)
Va first speed Vb second speed

Claims (5)

When the shift lever is in the drive range position, either the automatic shift mode that automatically shifts according to the running state of the vehicle, or the direct mode that temporarily shifts manually by operating the shift switch A control method for an automatic transmission that is selectable and automatically returns to an automatic transmission mode when a predetermined time has elapsed from when a predetermined return request condition is satisfied when the direct mode is selected,
A mode determination step for determining whether or not the direct mode has been executed;
A vehicle speed detection process for detecting the vehicle speed in the direct mode;
An accelerator opening detection step for detecting the accelerator opening in the direct mode;
A rapid acceleration determination step of determining a rapid acceleration state when the accelerator opening detected in the accelerator opening detection step is greater than or equal to a predetermined threshold, and determining a non-rapid acceleration state when less than the predetermined threshold;
A return prohibiting step for prohibiting automatic return to the automatic shift mode when it is determined in the sudden acceleration determination step that the vehicle is in a sudden acceleration state;
In the rapid acceleration determination step, the predetermined threshold is lowered as the vehicle speed detected in the vehicle speed detection step is higher.   In the sudden acceleration determination step, as the predetermined threshold, the first threshold is used when determining from the non-rapid acceleration state to the rapid acceleration state, and when determining from the sudden acceleration state to the non-rapid acceleration state, The second threshold value lower than the first threshold value is used, and at least one of the first threshold value and the second threshold value is set to be lower as the vehicle speed detected in the vehicle speed detection step is higher. Control method for automatic transmission.   3. The method of controlling an automatic transmission according to claim 2, wherein in the rapid acceleration determination step, both the first threshold value and the second threshold value are lowered as the vehicle speed detected in the vehicle speed detection step is higher. When the shift lever is in the drive range position, either the automatic shift mode that automatically shifts according to the running state of the vehicle, or the direct mode that temporarily shifts manually by operating the shift switch A control device for an automatic transmission that can be selected,
A vehicle speed sensor for detecting the vehicle speed;
An accelerator opening sensor for detecting the accelerator opening;
When the accelerator opening detected by the accelerator opening sensor is equal to or greater than a predetermined threshold, it is determined that the vehicle is in a rapid acceleration state, and when the accelerator opening is less than the predetermined threshold, the non-rapid acceleration state is determined. A controller that automatically returns to the automatic shift mode when a predetermined time has elapsed from when the return request condition is satisfied, and prohibits automatic return to the automatic shift mode in a sudden acceleration state,
The controller for an automatic transmission, wherein the controller lowers the predetermined threshold as the vehicle speed detected by the vehicle speed sensor in the direct mode increases. When the shift lever is in the drive range position, either the automatic shift mode that automatically shifts according to the running state of the vehicle, or the direct mode that temporarily shifts manually by operating the shift switch A control device for an automatic transmission that is selectable and automatically returns to an automatic transmission mode when a predetermined time has elapsed from when a predetermined return request condition is satisfied when the direct mode is selected,
Mode determination means for determining whether or not the direct mode has been executed;
Vehicle speed detection means for detecting the vehicle speed in direct mode;
An accelerator opening detecting means for detecting the accelerator opening in the direct mode;
A rapid acceleration determining means for determining that the accelerator opening is detected when the accelerator opening detected by the accelerator opening detecting means is equal to or greater than a predetermined threshold, and that the accelerator opening is less than the predetermined threshold;
A return prohibiting means for prohibiting an automatic return to the automatic shift mode when the sudden acceleration determining means determines that it is in a sudden acceleration state;
A control device for an automatic transmission, comprising: setting means for setting the predetermined threshold value to be lower as the vehicle speed detected by the vehicle speed detection means is higher.

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