JP2021063568A - Shift control device of automatic transmission - Google Patents

Abstract

To provide a shift control device of an automatic transmission capable of improving an operation feeling of a driver.SOLUTION: A shift control device of an automatic transmission (T) comprises input shafts (11, 12) to which drive force of a drive source is input through clutches (C1, C2), an output shaft (13) which is connected to drive wheels (W), and a plurality of gear trains which selectively couples the input shafts (11, 12) and output shaft (13) to each other, and can allows manual shifting based upon driver's operation. If driver's down-shift operation from a current shift stage to a target shift stage is detected, the automatic transmission (T) is permitted to make a down shift as long as the driver intends to reduce the speed of the vehicle even if rotating speeds of the input shafts (11, 12) exceed a predetermined allowable upper-limit rotating speed (RE).SELECTED DRAWING: Figure 1

Description

The present invention relates to a shift control device for shifting a speed of an automatic transmission provided in a vehicle.

The transmission (automatic transmission) provided in the vehicle is provided with a first input shaft in which odd-speed transmission gears are arranged and a second input shaft in which even-stage transmission gears are arranged, and the driver can operate the paddle. By switching the meshing of the transmission gears, the rotation of a drive source such as an engine is changed and transmitted to the output shaft (for example, Patent Document 1). In the automatic transmission, the upshift or downshift paddle (manual shift lever) provided on the steering wheel is operated, or the select lever is moved to the "M" range (manual shift range) for operation. As a result, there are some automatic transmissions that can be manually operated (for example, Patent Documents 2 and 3).

Japanese Unexamined Patent Publication No. 2019-78270 Japanese Unexamined Patent Publication No. 2013-086595 Japanese Unexamined Patent Publication No. 2019-1310060

By the way, in an automatic transmission capable of manual shifting as described above, when a downshift operation is performed by a downshift paddle, the rotation of the next gear (the gear after gear shifting or the target gear) is rotated. In a region where the number exceeds the upper limit rotation speed RE (rev limit) of the engine (drive source) and the engine becomes over-rotated, the engine may be over-rotated. Therefore, in the conventional control, when there is a possibility that the engine speed after shifting exceeds the upper limit speed RE due to the downshift operation by the downshift paddle, the driver's downshift command is not accepted (as invalid). Shift control is performed to maintain the shift (that is, do not allow downshifting to the next shift).

However, if the downshift is not executed when the driver commands the downshift by operating the downshift paddle, the driver feels that the downshift command has been ignored and feels uncomfortable with the operation feeling. In particular, when driving in an environment where a high deceleration occurs in the vehicle such as circuit driving, the driver's downshift command may be invalidated more often, which may cause a sense of discomfort due to the operation feeling. In addition, the driving time of the vehicle may be affected because the downshift is not performed by the driver's intention. Furthermore, especially on a circuit, the driver may intuitively grasp the current shift stage by the number of times the downshift paddle is operated, but the driver is operating the downshift paddle. If the downshift is not carried out, the driver may not be able to grasp the current shift stage while the vehicle is running.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a speed change control device for an automatic transmission capable of solving the above problems and improving the operation feeling of a driver.

In order to achieve the above object, the present invention connects the driving force of the driving source (E) to the input shafts (11, 12) input via the clutches (C1, C2) and the driving wheels (W). A plurality of gear trains that selectively connect the output shaft (13), the input shafts (11, 12), and the output shaft (13) are provided, and manual shifting based on the driver's operation is possible. A shift control device for an automatic transmission (T), the downshift operation detecting means (U) for detecting a downshift operation from the current gear to the target gear by the driver, and the automatic transmission (T). The downshift permitting means includes a downshift permitting means for permitting the downshift, and when the downshift operation is detected by the downshift operation detecting means, the downshift permitting means rotates the input shafts (11, 12). Allows the downshift of the automatic transmission (T) on condition that the driver intends to decelerate the vehicle even when the speed exceeds a predetermined upper limit rotation speed (RE). It is characterized by.

In this case, the determination that the driver intends to decelerate the vehicle is determined by operating the brake operator (110) for decelerating the vehicle, and the accelerator operator for accelerating the vehicle. It may be a condition that the operation of (100) is not performed and the deceleration of the vehicle is equal to or less than a predetermined set value (VA1).

Further, the upper limit rotation speed (RE) is the allowable rotation speed of the drive source (E) when shifting from the current shift stage to the target shift stage by engaging the other clutches (C1 and C2). It may be a rotation speed that causes an over-rotation state exceeding a number.

According to the present invention, even when the rotation speed of the input shaft of the transmission exceeds a predetermined upper limit value, the downshift operation is permitted provided that the driver intends to decelerate the vehicle (effective). Therefore, there is no possibility that the driver of the vehicle feels uncomfortable. In addition, there is no possibility that the traveling time of the vehicle will be affected. Further, the driver can accurately grasp the current shift stage while the vehicle is running. As a result, the driver's feeling of operation can be effectively improved.

Further, as a specific embodiment of the automatic transmission (T) controlled by this shift control device, the clutches (C1, C2) are composed of a pair of clutches (C1, C2), and the input shafts (11, 12). ) Consists of a pair of input shafts (11, 12), one input shaft (11, 12) is connected to the engine (E) by engagement of one clutch (C1, C2), and the other clutch (C1, 12) is connected. The other input shaft (11, 12) is connected to the drive source (E) by the engagement of C2), and the one clutch (C1, C2) is engaged to engage the one input shaft (11, 12). With the current shift stage established between the output shaft (13) and the output shaft (13), the other clutch (C1, C2) is disengaged and the other input shaft (11, 12) and the output shaft (11, 12) are disengaged. By pre-shifting the target shift stage with 13), disengaging the one clutch (C1, C2) and engaging the other clutch (C1, C2), the current shift stage is released. The shift may be made to the target shift stage.

Further, the shift control device of the automatic transmission includes a downshift executing means (U) for executing the downshift of the automatic transmission (T), and the downshift executing means is automatically operated by the downshift permitting means. When the downshift of the transmission is permitted, after that, the input shaft (11, 12) waits until the rotation speed becomes equal to or less than the upper limit rotation speed (RE), and the rotation speed of the input shaft (11, 12) becomes high. The downshift of the automatic transmission (T) may be executed when the upper limit rotation speed (RE) or less is reached.

In this case, the downshift executing means measures the elapsed time during the standby, and the rotation speed of the input shafts (11, 12) is the upper limit rotation speed by the time when the elapsed time elapses. If the speed does not fall below (RE), the automatic transmission (T) may be returned to the current shift stage without being downshifted.

Alternatively, the downshift executing means may execute the downshift of the automatic transmission (T) when the driver operates the accelerator operator (100) during the standby. Instead, it may be returned to the current shift stage.

Alternatively, the downshift executing means sets an allowable maximum rotation speed (RM) at which the rotation speed of the input shafts (11, 12) is larger than the upper limit rotation speed (RE) during the standby. If it exceeds the limit, the automatic transmission (T) may be returned to the current shift stage without being downshifted.

According to the present invention, even when the rotation speed of the input shaft exceeds a predetermined upper limit rotation speed, the automatic transmission is downshifted on condition that the driver intends to decelerate the vehicle. By allowing the driver to operate the vehicle, the driver's feeling of operation can be effectively improved.

It is a figure which shows typically the basic structure of the transmission (automatic transmission) of the vehicle provided with the shift control device which concerns on this invention. It is a block diagram of a shift control system. It is a flow chart which shows the control procedure of the shift control device. It is a timing chart which shows the control operation which concerns on Embodiment 1. FIG. It is a timing chart which shows the control operation which concerns on Embodiment 2. It is a timing chart which shows the control operation which concerns on Embodiment 3. It is a timing chart which shows the control operation which concerns on Embodiment 4. It is a timing chart which shows the control operation which concerns on Embodiment 5.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[Basic configuration of transmission]
First, a basic configuration of a transmission whose shift control is performed by the shift control device according to the present invention will be described below with reference to FIG.

As shown in FIG. 1, the twin clutch type transmission (automatic transmission) T having 9 forward speeds and 1 reverse speed has a first input shaft 11, a second input shaft 12, and a first input shaft T arranged in parallel with each other. It includes an output shaft 13, a second output shaft 14, and an idle shaft 15. The main input shaft 17 connected to the engine (drive source) E via the flywheel 16 is connected to the first input shaft 11 via the first clutch C1 and the first input via the second clutch C2. It is connected to a drive gear 18 that is rotatably supported on the shaft 1. The drive gear 18 meshes with the idle gear 19 fixed to the idle shaft 15, and the idle gear 19 meshes with the driven gear 20 fixed to the second input shaft 12. Therefore, when the first clutch C1 is engaged, the driving force of the engine E is transmitted to the first input shaft 11 in the path of the flywheel 16 → the main input shaft 17 → the first clutch C1, and when the second clutch C2 is engaged. , The driving force of the engine E is transmitted to the second input shaft 12 by the route of the flywheel 16 → the main input shaft 17 → the second clutch C2 → the drive gear 18 → the idle gear 19 → the driven gear 20.

The 1st speed input gear 21 fixed to the 1st input shaft 11 meshes with the 1st speed output gear 23 supported by the 1st output shaft 13 via the one-way clutch 22. The 3rd speed input gear 24 and the 5th speed input gear 25 are supported on the 1st input shaft 11 so as to be relatively rotatable, and these 3rd speed input gear 24 and the 5th speed input gear 25 use the 3rd speed-5th speed synchro device S1. It can be selectively coupled to the first input shaft 11 via. A 7-speed input gear 26 and a 9-speed input gear 27 are supported on the first input shaft 11 so as to be relatively rotatable, and the 7-speed input gear 26 and the 9-speed input gear 27 are the 7-speed-9-speed synchro device S2. It can be selectively coupled to the first input shaft 11 via.

The 2nd input shaft 12 supports the 2nd speed input gear 28 and the 4th speed input gear 29 so as to be relatively rotatable, and these 2nd speed input gear 28 and the 4th speed input gear 29 use the 2nd speed-4th speed synchro device S3. It can be selectively coupled to the second input shaft 12 via. Further, a 6-speed input gear 30 and an 8-speed input gear 31 are supported on the second input shaft 12 so as to be relatively rotatable, and the 6-speed input gear 30 and the 8-speed input gear 31 are a 6-speed-8-speed synchro device S4. It can be selectively coupled to the second input shaft 12 via.

On the first output shaft 13, a 3-speed-reverse output gear 32 that meshes with the 3-speed input gear 24 is fixedly installed, and a 2-speed output gear 33 that meshes with the 2-speed input gear 28 is fixedly installed. The reverse idle gear 34, which is supported by the idle shaft 15 so as to be relatively rotatable and can be coupled to the idle shaft 15 by the reverse synchro device S5, meshes with the third speed-reverse output gear 32.

The 5-speed input gear 25 and the 4-speed input gear 29 mesh with the common 4-speed-5-speed output gear 35, and the 7-speed input gear 26 and the 6-speed input gear 30 mesh with the common 6-speed-7-speed output gear 36. Then, the 9th speed input gear 27 and the 8th speed input gear 31 mesh with the common 8th speed-9th speed output gear 37.

The 3-speed-reverse output gear 32 meshes with the final gear 38 fixed to the second output shaft 14, and the first bevel gear 39 fixed to the second output shaft 14 meshes with the second bevel gear 40 provided to the differential gear D. Then, the drive shaft 41 extending from the differential gear D
, 41 are connected to the left and right drive wheels W, W.

Therefore, when all the 3rd-5th speed synchro devices S1 to the reverse synchro device S5 are disengaged, the one-way clutch 22 is engaged and the 1st speed shift stage is established. Further, when the 2nd speed input gear 28 is coupled to the 2nd input shaft 12 by the 2nd speed-4th speed synchro device S3, the 2nd speed shift stage is established, and the 3rd speed input gear 24 is input to the 1st speed by the 3rd speed-5th speed synchro device S1. When connected to the shaft 11, the 3rd gear is established, and when the 4th gear 29 is connected to the 2nd input shaft 12 in the 2nd-4th synchro device S3, the 4th gear is established and the 3rd-5th synchro is established. When the 5th speed input gear 25 is connected to the 1st input shaft 11 in the device S1, the 5th speed shift stage is established, and when the 6th speed input gear 30 is connected to the 2nd input shaft 12 in the 6th to 8th speed synchro device S4, the 6th speed is established. When the shift gear is established and the 7-speed input gear 26 is connected to the first input shaft 11 in the 7-speed-9-speed synchro device S2, the 7-speed shift gear is established and the 8-speed input gear is established in the 6-speed-8-speed synchro device S4. When the 31 is connected to the second input shaft 12, the 8-speed gear is established, and when the 9-speed input gear 27 is connected to the first input shaft 11 in the 7-speed-9-speed synchro device S2, the 9-speed gear is established. Then, when the reverse idle gear 34 is coupled to the idle shaft 15 by the reverse synchro device S5, the reverse shift stage is established.

Then, among the 1st to 9th speeds, the 1st clutch C1 is set when the odd number 1st speed, 3rd speed, 5th speed, 7th speed and 9th speed are established. The second clutch C2 is engaged when the second gear, the fourth gear, the sixth gear, and the eighth gear, which are even gears, are established.

For example, as an example of upshifting, the procedure of sequential shifting from the 2nd speed to the 3rd speed will be described. The 2nd-4th speed synchro device S3 connects the 2nd speed input gear 28 to the 2nd input shaft 12. In a state where the 2nd clutch C2 is engaged and the 2nd speed gear is established, the 3rd speed-5th speed synchro device S1 is pre-shifted to connect the 3rd speed input gear 24 to the 1st input shaft 11 in this state. By engaging the first clutch C1 while disengaging the second clutch C2, it is possible to upshift from the second gear to the third gear without interrupting the torque transmission.

Further, for example, when the procedure of sequential shifting from the 5th gear to the 4th gear is described as an example of downshifting, the 5th speed input gear 25 is coupled to the 1st input shaft 11 by the 3rd speed-5th speed synchro device S1. In a state where the first clutch C1 is engaged and the 5th speed shift stage is established, the 2nd to 4th speed synchro device S3 is pre-shifted to connect the 4th speed input gear 29 to the 2nd input shaft 12. By engaging the second clutch C2 while disengaging the first clutch C1 from this state, it is possible to downshift from the 5th gear to the 4th gear without interrupting the torque transmission.

As described above, the so-called twin-clutch type transmission T of the present embodiment enables clutch-to-clutch shifting without torque loss by the pre-shift operation, and enables direct shifting suitable for sporty driving. become. In normal shift control, the above clutch-to-clutch shift is performed, but in the downshift shift by operating the downshift paddle by the driver described below, the clutch-to-clutch shift is mainly for the purpose of improving responsiveness. Instead, the clutches (first clutch C1 and second clutch C2) are released to adjust the number of revolutions of the engine E, and then the clutch is engaged to perform the shifting operation.

As shown in FIG. 2, the electronic control unit U that controls the shift of the transmission T detects the operation of the upshift switch Sa that detects the operation of the upshift paddle operated by the driver and the operation of the downshift paddle. Downshift switch Sb, shift position sensor Sc that detects the current shift stage of the transmission T, vehicle speed sensor Sd that detects the vehicle speed, and an accelerator pedal (accelerator operator) that is operated (depressed) by the driver. The accelerator pedal opening sensor Se that detects the operation amount of 100 (accelerator pedal opening), the brake switch Sf that detects the operation amount (brutch on / off) of the brake pedal (brutch operator) 110, and the throttle valve of the engine E. The throttle actuator Aa that controls the engine rotation speed by operating the above, the speed change actuator Ab that operates the synchronization devices S1 to S5 of the transmission T to change the speed, and the first clutch C1 and the second clutch C2 are engaged and engaged. The clutch actuator Ac to be disengaged is connected.

By the way, the vehicle provided with the transmission T having the above configuration is provided with the shift control device according to the present invention. Next, the shift control by the shift control device will be described.

[Speed control device]
In the shift control device according to the present invention, when the driver operates the downshift paddle while the vehicle is running, the input related to the shift stage after the shift among the first input shaft 11 and the second input shaft 12 When the rotation speed of the shaft (hereinafter referred to as the next stage rotation shaft or the next stage shaft) exceeds the predetermined upper limit rotation speed RE (rev limit), in principle, the driver operates the downshift paddle. It is not accepted as invalid, but on the condition that the driver intends to decelerate the vehicle, as an exception, the operation of the downshift paddle is enabled and the downshift is permitted (the in-gear operation of the downshift is performed). There is.

Here, as shown in FIG. 3, the driver determines that the driver intends to decelerate the vehicle by pressing the brake pedal 110 and turning on the signal (BrksSW signal) output from the brake switch (BrksSW) Sf. The condition is that the accelerator pedal opening degree is 0% (required driving force = 0) and the deceleration of the vehicle is equal to or less than a predetermined set value. When these three conditions are satisfied, it is determined that the driver intends to decelerate the vehicle. Then, at this time, if a downshift operation is performed by the downshift paddle, this downshift operation is accepted as valid.

By the way, various modes can be considered for the shift control of the transmission T after the downshift operation by the downshift paddle is accepted as effective. Five embodiments will be described with reference to FIGS. 4 to 8 as an example of a case where a downshift operation is performed from the gear) to the next gear (the gear after the gear, that is, the target gear).

<Embodiment 1>
FIG. 4 is a timing chart showing a control operation according to the first embodiment by the shift control device. In the timing chart of the figure, the accelerator pedal opening AP, the required driving force MW, the on / off of the brake switch Sf, the on / off of the downshift switch Sb (whether or not the downshift paddle is operated), the target gear stage TG, and the actual gear stage MG. , Vehicle speed V, Vehicle speed calculation acceleration VA, previous stage (current shift stage) shaft rotation speed R1, next stage (target shift stage) shaft rotation speed R2, previous stage clutch torque Tr1, next stage clutch torque Tr2, engine torque TrE, each progress It shows the change over time. The front-stage clutch torque Tr1 and the next-stage clutch torque Tr2 are the clutch torques of the clutch applied to the front stage and the clutch applied to the next stage of the first clutch C1 and the second clutch C2, respectively. The same applies to FIGS. 5 to 8 below.

In this embodiment, the brake switch Sf is on, the accelerator pedal opening AP is 0, the required driving force MW is 0 or a negative value, and the next-stage shaft rotation speed R2 falls below the in-gear permitted rotation speed at time t1. .. As a result, the downshift operation by the driver's downshift paddle can be accepted. The in-gear permitted rotation speed here is set to a rotation speed higher than the upper limit rotation speed (RED NE: rev limit) RE. After that, at time t2, the driver performs a downshift operation with the downshift paddle to turn on the downshift switch Sb, whereby the target gear stage TG is lowered from the N speed stage to the N-1 speed stage. At this point, the next-stage shaft rotation speed R2 is still equal to or higher than the upper limit rotation speed RE. That is, by operating the downshift paddle while the brake pedal 110 is being operated, the downshift operation by the downshift paddle is accepted even if the next-stage shaft rotation speed R2 is equal to or higher than the upper limit rotation speed RE. After that, at time t3, the front-stage clutch torque Tr1 is reduced and the in-gear is performed. After that, the next-stage shaft rotation speed R2 falls below the upper limit rotation speed RE at time t4, and the in-gear is completed at time t5. After that, when the driver takes his foot off the brake pedal 110 (BrksSW signal is OFF) and depresses the accelerator pedal 100, the engine speed NE gradually increases.

<Embodiment 2>
FIG. 5 is a timing chart showing a control operation according to the second embodiment by the shift control device. In this embodiment, the driver performs a downshift operation with the downshift paddle at time t1 when the brake switch Sf is on, the accelerator pedal opening AP is 0, and the required driving force MW is 0 or a negative value. As a result, the downshift switch Sb is turned on, which causes the target gear stage TG to go down from the N speed stage to the N-1 speed stage. After that, at time t2, the next-stage shaft rotation speed R2 falls below the in-gear permitted rotation speed. As a result, the downshift operation by the driver's downshift paddle can be accepted, and the in-gear is performed. At this point, the next-stage shaft rotation speed R2 is still equal to or higher than the upper limit rotation speed RE. After that, until the next-stage shaft rotation speed R2 falls below the upper limit rotation speed RE at time t4, the engine rotation speed NE is kept on standby at the upper limit rotation speed RE. As a result, the in-gear is completed when the next-stage shaft rotation speed R2 falls below the upper limit rotation speed RE at time t4.

Further, the downshift paddle is operated only once until the next-stage shaft rotation speed R2 falls below the upper limit rotation speed RE. Therefore, as shown in FIG. 5, the time t3 from the time when the downshift paddle is operated at time t1 until the next stage shaft rotation speed R2 falls below the upper limit rotation speed RE and the in-gear is completed at time t4. Even if there is an operation of the downshift paddle, the operation of the downshift paddle is not accepted. In this way, instead of accepting the operation of the downshift paddle again when the shift (in-gear operation) is completed, the downshift paddle is provided on the condition that the next-stage shaft rotation speed R2 is lower than the upper limit rotation speed RE. By accepting the operation, it becomes easier to reflect the driver's intention, and by accepting the operation before the clutch is engaged, it becomes possible to realize a faster next-speed shift.

<Embodiment 3>
FIG. 6 is a timing chart showing a control operation according to the third embodiment by the shift control device. In this embodiment, the driver performs a downshift operation with the downshift paddle at time t1 when the brake switch Sf is on, the accelerator pedal opening AP is 0, and the required driving force MW is 0 or a negative value. As a result, the downshift switch Sb is turned on, which causes the target gear stage TG to go down from the N speed stage to the N-1 speed stage. Further, the timer count starts at this time t1. After that, at time t2, the next-stage shaft rotation speed R2 falls below the in-gear permitted rotation speed. As a result, the downshift operation by the driver's downshift paddle can be accepted, and the in-gear is performed. At this point, the next-stage shaft rotation speed R2 is still equal to or higher than the upper limit rotation speed RE. After that, until the timer counts up (times out) at time t3, if the next-stage shaft rotation speed R2 does not fall below the upper limit rotation speed RE, the engine speed NE is kept at the upper limit rotation speed RE and is kept on standby. Then, when the timer counts up at time t3 without the next-stage shaft rotation speed R2 falling below the upper limit rotation speed RE, the target gear stage TG is increased (returned) from the N-1 speed stage to the N speed stage. As a result, after time t3, the engine speed decreases and returns to the previous shaft speed. That is, the timer counts up to shift to the upshift (without executing the downshift), thereby returning to the current shift stage. Further, after the time t3 when the timer counts up, the downshift operation by the driver's downshift paddle can be accepted again. As a result, the responsiveness of shifting can be improved, and the driver's intention can be easily reflected.

As described above, in the present embodiment, when the timer counts up (down by the driver) as a condition for returning to the previous stage (front gear stage) in a state where the next stage shaft rotation speed R2 exceeds the in-gear permitted rotation speed after the start of the in-gear. When a predetermined time has elapsed from the operation of the shift paddle), the engine is returned to the previous stage while off-gearing.

<Embodiment 4>
FIG. 7 is a timing chart showing a control operation according to the fourth embodiment by the shift control device. In this embodiment, the driver performs a downshift operation with the downshift paddle at time t1 when the brake switch Sf is on, the accelerator pedal opening AP is 0, and the required driving force MW is 0 or a negative value. As a result, the downshift switch Sb is turned on, which causes the target gear stage TG to go down from the N speed stage to the N-1 speed stage. After that, at time t2, the next-stage shaft rotation speed R2 falls below the in-gear permitted rotation speed. As a result, the downshift operation by the driver's downshift paddle can be accepted, and the in-gear is performed. At this point, the next-stage shaft rotation speed R2 is still equal to or higher than the upper limit rotation speed RE. After that, when the driver depresses the accelerator pedal 100 at time t3, the accelerator pedal opening AP and the required driving force MW become positive values. As a result, the target gear stage TG is increased (returned) from the N-1 speed stage to the N speed stage. Therefore, after the time t3, the engine speed NE gradually decreases and returns to the previous shaft speed R1. That is, if the driver depresses the accelerator pedal 100 after the start of the in-gear until the next-stage shaft rotation speed R2 falls below the upper limit rotation speed RE, it is determined that the driver has an intention to accelerate the vehicle. Then, in order to give priority to outputting the driving force, the shift is made to the upshift (without executing the downshift). That is, although the driving force cannot be transmitted during the in-gear operation, if the driver intends to accelerate the vehicle, the shift stage is returned to the front stage so that the driving force can be transmitted.

As described above, in the present embodiment, the driver depresses the accelerator pedal 100 as a condition for returning to the previous stage (front gear stage) in a state where the next stage shaft rotation speed R2 exceeds the in-gear permitted rotation speed after the start of the in-gear. In such a case (when the driver intends to accelerate the vehicle), the vehicle is returned to the previous stage while off-gearing.

<Embodiment 5>
FIG. 8 is a timing chart showing a control operation according to the fifth embodiment by the shift control device. In this embodiment, the driver performs a downshift operation with the downshift paddle at time t1 when the brake switch Sf is on, the accelerator pedal opening AP is 0, and the required driving force MW is 0 or a negative value. As a result, the downshift switch Sb is turned on, which causes the target gear stage TG to go down from the N speed stage to the N-1 speed stage. Further, the timer count starts at this time t1. After that, at time t2, the next-stage shaft rotation speed R2 falls below the in-gear permitted rotation speed. As a result, the downshift operation by the driver's downshift paddle can be accepted, and the in-gear is performed. At this point, the next-stage shaft rotation speed R2 is still equal to or higher than the upper limit rotation speed RE. After that, at time t3, the driver depresses the brake pedal 110, and the brake switch Sf is turned off. As a result, for example, in the case of a downhill road, the vehicle speed that had been decelerated until then gradually increases after time t3. In addition, the next-stage shaft rotation speed R2 gradually increases accordingly. Then, at time t4, the next-stage shaft rotation speed R2 exceeds the allowable maximum rotation speed RM. As a result, the target gear stage TG is increased (returned) from the N-1 speed stage to the N speed stage. Therefore, after the time t4, the engine speed NE gradually decreases and returns to the previous shaft speed. The permissible maximum rotation speed RE here is the permissible maximum value on the upper limit side of the upper limit rotation speed RE, and is a value larger than the upper limit rotation speed RE. This allowable maximum rotation speed RM considers the structural resistance of the transmission, such as the allowable rotation speed for avoiding unstable operation such as hunting due to twisting of the rotating shaft (shaft) in the transmission. It may be a value determined by.

As described above, in the present embodiment, the next-stage shaft rotation speed R2 is the maximum allowable rotation speed as a condition for returning to the previous stage (pre-gear stage) in a state where the next-stage shaft rotation speed R2 exceeds the in-gear permitted rotation speed after the start of the in-gear. When it is established that the RM is exceeded, the engine is returned to the previous stage while off-gearing.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and the scope of claims and the technical ideas described in the specification and drawings are Various modifications are possible within the range.

T transmission E engine (drive source)
11 1st input shaft 12 2nd input shaft 13 1st output shaft 14 2nd output shaft 15 Idle shaft 16 Flywheel 17 Main input shaft 18 Drive gear 19 Idle gear 20 Driven gear 22 One-way clutch 21, 24-31 Input gear 23, 32, 33 Output gear D Differential gear W, W Drive wheel C1 1st clutch C2 2nd clutch S1 to S5 Synchro device 100 Accelerator pedal 110 Brake pedal Aa Throttle actuator Ab Shift actuator Ac Clutch actuator Sa Upshift switch Sb Downshift switch Sc Gear shift position sensor Sd Vehicle speed sensor Se Accelerator pedal opening sensor Sf Brake switch U Electronic control unit

Claims (8)

It includes an input shaft in which the driving force of the drive source is input via a clutch, an output shaft connected to the drive wheels, and a plurality of gear trains that selectively connect the input shaft and the output shaft. , A shift control device for automatic transmissions that can shift manually based on the driver's operation.
A downshift operation detecting means for detecting a downshift operation from the current gear to the target gear by the driver, and
A downshift permitting means for permitting a downshift of the automatic transmission is provided.
When the downshift operation is detected by the downshift operation detecting means,
The downshift permitting means is the automatic transmission on condition that the driver intends to decelerate the vehicle even when the rotation speed of the input shaft exceeds a predetermined upper limit rotation speed. A shift control device for an automatic transmission, which is characterized by allowing a downshift of an automatic transmission. To determine that the driver intends to decelerate the vehicle, the brake operator for decelerating the vehicle is operated, and the accelerator operator for accelerating the vehicle is operated. The shift control device for an automatic transmission according to claim 1, wherein the deceleration of the vehicle is not less than or equal to a predetermined set value. The clutch consists of a pair of clutches.
The input shaft consists of a pair of input shafts.
The engagement of one clutch connects one input shaft to the engine and the engagement of the other clutch connects the other input shaft to the drive source.
With the one clutch engaged and the current speed change established between the one input shaft and the output shaft, the other clutch is disengaged and the other input shaft and the output shaft are disengaged. The target shift is pre-shifted between the two, and the other clutch is disengaged and the other clutch is engaged to shift from the current shift to the target shift. The speed change control device for an automatic transmission according to claim 1 or 2. The upper limit rotation speed is a rotation speed at which the rotation speed of the drive source exceeds the permissible rotation speed when shifting from the current shift stage to the target shift stage by engaging the other clutch. The speed change control device for an automatic transmission according to claim 3. A downshift execution means for executing the downshift of the automatic transmission is provided.
When the downshift permitting means permits the downshift of the automatic transmission, the downshift executing means waits until the rotation speed of the input shaft becomes equal to or less than the upper limit rotation speed, and then rotates the input shaft. The speed change control device for an automatic transmission according to any one of claims 1 to 4, wherein the downshift of the automatic transmission is executed when the number becomes equal to or less than the upper limit rotation speed. The downshift execution means measures the elapsed time during the standby and measures the elapsed time.
If the rotation speed of the input shaft does not fall below the upper limit rotation speed by the time when the elapsed time elapses, the automatic transmission is not downshifted and is returned to the current shift stage. The speed change control device for an automatic transmission according to claim 5. When the driver operates the accelerator controller during the standby, the downshift executing means returns the automatic transmission to the current shift stage without executing the downshift of the automatic transmission. The shift control device for an automatic transmission according to claim 5 or 6. The downshift executing means executes the downshift of the automatic transmission when the rotation speed of the input shaft exceeds the allowable maximum rotation speed, which is a set value larger than the upper limit rotation speed, during the standby. The shift control device for an automatic transmission according to claim 5 or 6, wherein the shift control device returns to the current shift stage without any trouble.

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