JP2006275226A - Shift control device of automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve drivability, when traveling on a mountain road of frequently causing ON/OFF operation of an accelerator pedal, by selecting an optimal shift stage so that a driver does not feel a sense of incompatibility, by reducing a case of shifting up even in a speed reduction state of returning the accelerator pedal at a stretch from the middle after starting to gently return the accelerator pedal. <P>SOLUTION: This invention is a shift control device of an automatic transmission, and is characterized by arranging a shift-up prohibition performance determining means for performing shift-up prohibition by a shift-up prohibiting means, when a shift-up prohibiting condition by an accelerator opening change rate is realized and a shift-up cancel condition is realized, after outputting a command signal for shifting up a shift stage from a present shift stage by a shift stage command means. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a shift control device for an automatic transmission, and in particular, the driver feels uncomfortable because there is less chance of shifting up even in a decelerating state where the accelerator pedal starts to be slowly returned and then the accelerator pedal is immediately returned from the middle. It is possible to select an optimal gear position that you do not feel, and this makes it possible to improve the drivability when driving on mountain roads where accelerator pedal depression and return operations are frequently performed. The present invention relates to a transmission control device.

  In an automatic transmission mounted on a vehicle, a shift means having a plurality of shift speeds is provided. In order to shift the speed change means, for example, as shown in FIG. 9, a shift speed selected from a vehicle speed and a throttle opening is set. A shift control device having a preset shift map is provided. The shift control device of the automatic transmission shifts by engaging or releasing the friction engagement element with a shift solenoid or the like so as to be a shift stage selected based on the shift map from the throttle opening and the vehicle speed at that time. The gears of the means are shifted up and down to change the speed.

  Here, shifting up / down down while driving on a winding road such as a mountain road where the accelerator pedal is frequently depressed and returned will be described. As shown in FIG. When the vehicle speed is point A, the gear position is 3rd. If the accelerator pedal is returned before the curve, the throttle opening and vehicle speed will move to point B, and the shift up to 4th will occur. Occurs and engine braking force is insufficient. After that, when the vehicle goes off the curve and the driver tries to accelerate again, the driving force is insufficient, so the driver steps on the accelerator pedal, and the throttle opening and the vehicle speed move to the point C to reach the third speed. A downshift occurs.

  Such shift-up / shift-down of the automatic transmission is not intended by the driver. The automatic transmission should inherently generate a suitable engine braking force toward the curve, and then shift to a gear position that provides the driving force required by the driver after exiting the curve.

Some shift control devices for such an automatic transmission prohibit upshifting for a certain period (predetermined time) when the rate of change in accelerator opening falls below a negative threshold value (set value). . As a result, when the driver suddenly returns the accelerator pedal before the curve, the shift control device of this automatic transmission is prohibited from shifting up for a predetermined time, so that an appropriate engine braking force is obtained before the curve. Thus, there is an effect that an appropriate driving force can be obtained when the vehicle escapes from the curve.
Patent Registration No. 3037369 Patent registration No. 3122083 JP-A-5-169136

In addition, the shift control device of the automatic transmission includes a shift operation that is continued when the sudden braking operation is started, and the shift operation is continued to end the shift, or the shift operation is interrupted and the shift before the shift is started. Some of them determine whether or not to return to the stage and prevent subsequent engine shifts to prevent engine stall.
Patent registration No. 3493741

  However, as shown in Patent Documents 1 to 3, in the shift control device for an automatic transmission that prohibits upshifting depending on the rate of change of the accelerator opening, the driver moves from point A to point D in FIG. Slowly return the accelerator pedal, then suddenly return the accelerator pedal and move to point B. From point A to point D, the rate of change in accelerator opening is close to 0, so upshifting is not prohibited and shifts to 4th speed. Even if the upshift occurs, and then the accelerator pedal is suddenly returned, the upshift is not prohibited.

  For this reason, the conventional shift control device for an automatic transmission has a problem of making the driver feel uncomfortable because upshifting is prohibited or not prohibited depending on how the accelerator pedal is returned.

  According to the present invention, an automatic transmission having a transmission means is provided, and a command signal for upshifting / downshifting is provided so that the transmission means of the automatic transmission becomes a shift stage selected based on a preset shift map. Accelerator opening degree change that calculates the accelerator opening change rate from the accelerator opening detected by the accelerator opening detecting means provided with the gear position command means for outputting, the accelerator opening detecting means capable of detecting the accelerator opening When a shift-up prohibiting condition in which the accelerator opening change rate calculated by the accelerator opening change rate calculating means is lower than a set value is satisfied, the speed change means is shifted up only for a predetermined time. In a shift control device for an automatic transmission provided with a shift-up prohibiting means for prohibiting, the shift means is shifted up from the current shift speed by the shift speed command means. If the shift-up prohibition condition based on the accelerator opening change rate is satisfied and the shift-up cancel condition is satisfied after the command signal to be output is output, the shift-up prohibition is executed by the shift-up prohibiting means. Prohibiting execution determining means is provided.

  In the shift control device for an automatic transmission according to the present invention, after the command signal for shifting up the speed change means from the current speed is output by the speed change command means by the shift up prohibition execution determination means, When the shift-up prohibition condition is satisfied and the shift-up cancel condition is satisfied, by starting the shift-up prohibition by the shift-up prohibiting means, the accelerator pedal is gradually returned, and the accelerator pedal is returned at a stroke from the middle. Therefore, it is possible to select the optimal gear position so that the driver does not feel uncomfortable, even in a slow deceleration state. It is possible to improve drivability when traveling on the road.

The shift control device for an automatic transmission according to the present invention can reduce the number of cases of shifting up even in a deceleration state in which the accelerator pedal is gradually returned and the accelerator pedal is immediately returned from the middle, and the driver feels uncomfortable. Thus, it is possible to select an optimum gear position, and to improve drivability.
Embodiments of the present invention will be described below with reference to the drawings.

  1 to 9 show an embodiment of the present invention. In FIG. 7, 2 is an engine mounted on a vehicle (not shown), and 4 is an automatic transmission. The automatic transmission 4 includes a torque converter 6 and an auxiliary transmission mechanism 8 that is a transmission means. The auxiliary transmission mechanism 8 has a plurality of shift stages including planetary gears (not shown) and the like, and is shifted up and down by the engagement / release of the friction engagement element 10 including a clutch, a brake, and the like, and is shifted.

  A valve body 12 is provided below the automatic transmission 4. The valve body 12 is provided with first and second solenoids 14 and 16 for shifting of a shift valve (not shown) for supplying hydraulic pressure to the friction engagement element 10 of the auxiliary transmission mechanism 8 to switch the engagement state. Yes.

  The first and second solenoids 14 and 16 for shifting are connected to the control unit 20 of the shift control device 18 of the automatic transmission 4. The control unit 20 includes an engine rotation sensor 22 that detects the rotation speed of the engine 2, a throttle opening sensor (throttle opening detection means) 24 that detects a throttle opening of a throttle valve (not shown) of the engine 2, and A vehicle speed sensor (vehicle speed detection means) 26 for detecting the vehicle speed from the rotational speed of the output shaft of the automatic transmission 4 and a shift position switch 28 for detecting the shift position of a shift lever (not shown) of the automatic transmission 4 are connected. Yes. The throttle opening sensor 24 also functions as an accelerator opening detecting means for detecting the accelerator opening of an accelerator pedal (not shown) that opens and closes the throttle valve.

  The control unit 20 of the shift control device 18 includes a shift map 30 (see FIG. 9) in which shift speeds selected from the vehicle speed and the throttle opening are set in advance, and is provided with shift speed calculation means 32, and the accelerator opening change rate. A calculation unit 34, a shift-up prohibiting unit 36, a shift-up cancel condition determining unit 38, a shift-up prohibition execution determining unit 40, and a shift speed command unit 42 are provided.

  The shift speed calculating means 32 calculates a shift speed based on the shift map shown in FIG. 9 from the throttle opening detected by the throttle opening sensor 24 and the vehicle speed detected by the vehicle speed sensor 26.

  The accelerator opening change rate calculating means 34 calculates the accelerator opening change rate from the throttle opening (accelerator opening) detected by the throttle opening sensor 24. The accelerator opening change rate is obtained by calculating the change amount of the accelerator opening per unit time.

  The shift-up prohibiting unit 36 is an auxiliary unit that is a speed change unit only when a shift-up prohibiting condition in which the accelerator opening change rate calculated by the accelerator opening change rate calculating unit 34 is lower than a set value is satisfied. Shifting up the transmission mechanism 8 is prohibited.

  The shift-up cancel condition determining means 38 determines whether or not a re-shifting is possible to return the auxiliary transmission mechanism 8 that is the shifting means that started the up-shifting to the original shift stage. The upshift cancellation condition is set according to the elapsed time after the upshift command signal is output or the hydraulic state of the friction engagement element 10 to be engaged and released by the upshift command signal.

  The shift-up prohibition execution determination unit 40 establishes a shift-up prohibition condition based on the accelerator opening change rate after a command signal for shifting up the auxiliary transmission mechanism 8 from the current gear stage is output by the gear stage command unit 42. When the upshift cancel condition is satisfied, the upshift prohibition by the upshift prohibiting means 36 is executed.

  The shift speed command means 42 outputs a command signal to the shift first and second solenoids 14 and 16 to operate the shift valve so that the shift speed selected by the shift speed calculation means 32 is achieved, and the friction The hydraulic pressure supplied to the combination element 10 is controlled. The friction engagement element 10 is engaged or released by the operating hydraulic pressure, and shifts up and down the shift speed of the auxiliary transmission mechanism 8 to change the speed.

  In this way, the shift control device 18 of the automatic transmission 4 shifts based on the shift map from the throttle opening detected by the throttle opening sensor 24 and the vehicle speed detected by the vehicle speed sensor 26, as shown in FIG. A shift speed calculating means 32 for calculating the speed is provided, and an accelerator opening change rate calculating means 34 for calculating an accelerator opening change rate from the throttle opening (accelerator opening) detected by the throttle opening sensor 24 is provided. Shift-up prohibiting means 36 for prohibiting the upshifting of the auxiliary transmission mechanism 8 only when a predetermined condition is satisfied when the shift-up prohibiting condition in which the accelerator opening change rate calculated by the opening change rate calculating means 34 is lower than the set value is satisfied. The shift-up can is used to determine whether or not the auxiliary transmission mechanism 8 that has started upshifting can be re-shifted back to the original gear position. And a shift-up prohibiting condition based on the accelerator opening change rate is satisfied after a command signal for shifting up the auxiliary transmission mechanism 8 from the current shift stage is output by the shift stage commanding section 42, and When the shift-up cancel condition is satisfied, a shift-up prohibition execution determination unit 40 for executing the shift-up prohibition by the shift-up prohibition unit 36 is provided, and the shift-up prohibition determination unit 40 is used to shift to the shift stage selected by the shift stage calculation unit 32. A shift speed command means 42 is provided for controlling the hydraulic pressure supplied to the friction engagement element 10 by outputting a command signal to the first and second solenoids 14 and 16.

  Next, the operation of the shift control device 18 of the automatic transmission 4 will be described.

  With reference to the flowchart shown in FIG. When the control is started (100), the shift control device 18 of the automatic transmission 4 calculates the accelerator opening change rate (102).

  The accelerator opening change rate is obtained as a change amount per unit time (for example, for 20 msec) of the accelerator opening AP. Here, it is assumed that the rate of change in the accelerator opening is ΔAP, a negative value is obtained when the accelerator pedal is operated in the return direction, and a positive value is obtained when the accelerator pedal is operated in the depression direction.

  Next, the accelerator opening change rate ΔAP calculated (102) from the accelerator opening AP is compared with a threshold value (set value) of a preset change rate, so that the accelerator opening change rate ΔAP is It is determined whether the shift-up prohibition condition is satisfied when the change rate is less than the threshold value (104).

  In this determination (104), if the accelerator opening change rate ΔAP <the change rate threshold value is YES (the shift-up prohibition condition is satisfied), it is determined that the accelerator pedal is suddenly returned and the shift-up is prohibited ( 106) and processing the end (108). If this determination (104) is NO with the threshold value of the accelerator opening change rate ΔAP ≧ change rate (the shift-up prohibition condition is not satisfied), the process ends (108).

  Next, the shift-up prohibition cancellation determination will be described with reference to the flowchart of FIG. When the control is started (200), the shift control device 18 of the automatic transmission 4 determines whether or not upshifting is prohibited (202).

  If this determination (202) is NO while upshifting is not prohibited, it is the case where it is not determined that the upshifting prohibition condition is satisfied in the flowchart of FIG. The process ends (210).

  If this determination (202) is YES while shifting up is prohibited, it is determined whether the idle elapsed time is equal to or longer than the determination time (predetermined time) (204).

  If this determination (204) is YES with the elapsed idle time ≧ determination time, the shift-up prohibition is canceled (208), and the process ends (210). If this determination (204) is NO in the elapsed time of idle <determination time, it is determined whether the elapsed time of accelerator depression is equal to or longer than the determination time (predetermined time) (206).

  If this determination (206) is YES with the accelerator depression elapsed time ≧ determination time YES, the shift-up prohibition is canceled (208), and the process ends (210). If this determination (206) is NO with the accelerator depression elapsed time <determination time being NO, the processing ends (210) and the shift-up prohibition is continued.

  Next, the determination of the gear position will be described with reference to the flowchart of FIG. When the control is started (300), the shift control device 18 of the automatic transmission 4 stores the current shift speed (GP) in GPOLD (302), and determines the shift speed according to the shift map from the throttle opening and the vehicle speed. (304), input to the gear stage GP. For example, as shown in FIG. 9, the shift map is set in advance based on the throttle opening and the vehicle speed, thereby determining the shift stage.

  Following the determination of the gear position (304), it is determined whether an upshift has occurred (306). The occurrence of the shift up is performed by comparing GP and GPOLD. If GP> GPOLD, it is determined that the shift up has occurred.

  If no shift up has occurred in the determination (306), the process ends (316). If a shift up occurs in the determination (306) and the answer is YES, it is determined whether the shift up is prohibited (308).

  In this determination (308), if the shift-up is not prohibited and the answer is NO, the processing is terminated (316). If YES in this determination (308) while upshifting is prohibited, it is determined whether upshifting has been started and upshifting (310).

  If NO in this determination (310), the gear shift stage GP = GPOLD is returned to the previous gear shift stage (314), the shift up is prohibited and the process is terminated (316). If YES in this determination (310), it is determined whether re-shifting is possible based on the shift-up cancel condition (312).

  Whether or not re-shifting is possible can be determined by the elapsed time after the upshift is opened, the hydraulic pressure applied to the frictional engagement element 10 that is engaged and released by the upshift, and the like.

  In this determination (312), if the shift can be re-performed and the shift-up cancel condition is satisfied, GP = GPOLD is returned to the previous shift stage even after the shift-up is started (314), and the started shift-up is canceled. The process is terminated (316). In this determination (312), when the re-shift is not possible and the shift-up cancel condition is not satisfied, the shift-up is already in progress and the process is terminated to continue the shift-up (316).

  The above processing will be described according to the time charts of FIGS.

  FIG. 4 is a time chart showing a case where the accelerator pedal is suddenly returned before the shift up is started. In the time chart of FIG. 4, when the accelerator pedal is suddenly returned at time t0, the value of the accelerator opening change rate changes in the negative direction. Here, when the rate of change of the accelerator opening is lower than the threshold value, a shift up to the 4th speed usually occurs. However, the shift up is prohibited and the 3rd speed is maintained when the shift up prohibition condition is satisfied. . Thereafter, when the state where the accelerator pedal is depressed is continued from the time t1 for the determination time T, the shift-up prohibition is canceled and the upshift to the fourth speed is performed.

  FIG. 5 is a time chart showing a case where the accelerator pedal is suddenly returned within the re-transmission permission time after the start of upshifting. In the time chart of FIG. 5, unlike the case of FIG. 4, a shift-up occurs at time t0 due to the slow return of the accelerator pedal. Due to the failure of the condition, the upshift is not prohibited and the upshift to the fourth speed occurs. After that, when the accelerator pedal suddenly returns at time t1 and the accelerator opening change rate changes in the negative direction and becomes lower than the threshold value, the shift-up prohibition is determined by the establishment of the shift-up prohibition condition. .

  At this time, based on the elapsed time from the start of the shift, it is determined whether the re-shift is possible based on the re-shift permission time (from t0 to t2) as the upshift cancel condition. In this case, since the elapsed time has not reached the re-shift permission time and the re-shift can be performed when the shift-up cancel condition is satisfied, the shift-up is canceled, the shift is again performed, and the speed is returned to the third speed. Thereafter, as in the case of FIG. 4, when the state where the accelerator pedal is depressed is continued from the time t3 for the determination time T, the shift-up prohibition is canceled and the shift-up to the fourth speed is performed.

  FIG. 6 is a time chart showing a case where the accelerator pedal is suddenly returned after the re-transmission permission time has elapsed after the start of upshifting. In the time chart of FIG. 6, unlike the case of FIG. 5, it is a case where the re-transmission permission time has elapsed after the start of the upshifting. In this case, after the shift up is started at time t0, the accelerator pedal is suddenly returned at time t2 after the time t1 at which re-shift is possible, and the shift-up cancel condition is not satisfied after the re-shift permission time has elapsed. Therefore, the upshifting is continued without executing the upshifting prohibition.

  If the accelerator pedal is slowly returned in this way and the re-shift permission time has elapsed, the driver knows that the gear shift has been performed, and then the accelerator pedal is suddenly returned and the upshift is not cancelled. However, there is no sense of incongruity.

  As described above, the shift control device 18 of the automatic transmission 4 shifts by the accelerator opening change rate after the command signal for shifting up the auxiliary transmission mechanism 8 from the current gear position is output by the gear position command means 42. When the up prohibition condition is satisfied and the upshift cancellation condition is satisfied, the upshift prohibition by the upshift prohibiting means 36 is executed.

  As a result, the shift control device 18 of the automatic transmission 4 starts to slowly return the accelerator pedal, and it is less likely to shift up even in a deceleration state in which the accelerator pedal is returned at a stroke. It is possible to select an optimal gear position that will not be felt, thereby improving drivability when traveling on a mountain road or the like where the accelerator pedal is frequently depressed and returned.

  The shift-up cancel condition by the shift-up cancel condition determination means 38 is provided in the auxiliary transmission mechanism 8 that is engaged and released by the elapsed time after the output of the shift-up command signal or the shift-up command signal. Since it is set according to the hydraulic state of the friction engagement element 10 and the shift up cancel is impossible, the shift up control is performed as it is, so that the hunting phenomenon of the shift up / shift down does not occur. .

  In the above-described embodiment, the set value of the shift-up prohibition condition based on the accelerator opening change rate is set to a constant value. However, if it is determined that the vehicle is driving a continuous curve according to the behavior of the vehicle, the accelerator pedal By changing the setting value so that the shift-up prohibition condition is satisfied even when the pedal is returned slowly, the shift-up can be prohibited early, such as mountain roads where the accelerator pedal is frequently depressed and returned The drivability when traveling can be improved.

  The shift control device for an automatic transmission according to the present invention can reduce the number of cases of shifting up even in a decelerating state in which the accelerator pedal is gradually returned and the accelerator pedal is immediately returned from the middle, and the driver feels uncomfortable. The optimum shift speed can be selected and the drivability can be improved, and not only an automatic variable transmission equipped with a shift means having a plurality of shift speeds but also a stepless such as CVT. The present invention can also be applied to control of an automatic transmission provided with speed change means so that the speed change ratio can be changed.

It is a flowchart of the determination of the gear stage which shows the Example of the transmission control apparatus of an automatic transmission. It is a flowchart of determination of a shift up prohibition. It is a flowchart of cancellation determination of upshift prohibition. It is a time chart which shows the case where an accelerator pedal is suddenly returned before the start of a shift up. It is a time chart which shows the case where an accelerator pedal is rapidly returned within the re-transmission permission time after the start of upshifting. It is a time chart which shows the case where an accelerator pedal is returned suddenly after re-transmission permission time passes after the start of upshifting. It is a schematic block diagram of a transmission control apparatus. It is a control block diagram of a transmission control apparatus. It is a figure which shows the shift map by throttle opening and a vehicle speed.

Explanation of symbols

2 Engine 4 Automatic transmission 6 Torque converter 8 Auxiliary transmission mechanism 10 Friction engagement element 12 Valve body 14 Shift first solenoid 16 Shift second solenoid 18 Shift control device 20 Control unit 22 Engine rotation sensor 24 Throttle opening sensor 26 Vehicle speed sensor 28 Shift position switch 30 Shift map 32 Shift speed calculation means 34 Accelerator opening change rate calculation means 36 Shift up prohibition means 38 Shift up cancel condition determination means 40 Shift up prohibition execution determination means 42 Shift speed command means

Claims (2)

  A shift stage provided with an automatic transmission having a shift means, and outputting a shift-up / shift-down command signal so that the shift means of the automatic transmission becomes a shift stage selected based on a preset shift map There is provided an accelerator opening detection means capable of detecting the accelerator opening, provided with command means, and an accelerator opening change rate calculating means for calculating the accelerator opening change rate from the accelerator opening detected by the accelerator opening detection means. A shift-up that prohibits the shift-up of the speed change means only when a predetermined condition is satisfied when the shift-up prohibition condition in which the accelerator opening change rate calculated by the accelerator opening change rate calculating means is lower than a set value is satisfied. In a shift control device for an automatic transmission provided with a prohibiting means, a command for shifting up the shifting means from the current shifting speed by the shifting speed command means. When the shift-up prohibition condition based on the accelerator opening change rate is satisfied and the shift-up cancel condition is satisfied, the shift-up prohibition execution is executed to execute the shift-up prohibition by the shift-up prohibiting means. A shift control apparatus for an automatic transmission, characterized in that a determination means is provided.   The shift-up cancel condition is set according to the elapsed time since the output of the up-shift command signal or the hydraulic state of the friction engagement element provided in the transmission means that is engaged and released by the up-shift command signal. The shift control apparatus for an automatic transmission according to claim 1, wherein

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