JP7118526B2 - Upshift control device for automatic transmission - Google Patents

Description

The present invention relates to an upshift control device for an automatic transmission mounted on a vehicle.

Conventionally, the engagement pressure of a frictional engagement element that transitions from a disengaged state to an engaged state during an upshift is gradually increased, and torque-up control of the engine is executed during a torque phase (hereinafter referred to as "torque phase"). The engagement pressure during the torque phase of the frictional engagement element is controlled to a standby pressure at which the inertia phase (hereinafter referred to as "inertia phase") does not start. Disclosed is a control device for a vehicle that executes a first torque-down control to gradually reduce the torque of an engine when the elapsed time from the issuance of a command to set the engagement pressure of a frictional engagement element to standby pressure is greater than or equal to the standby time. (See Patent Document 1).

JP 2008-45567 A

In the above conventional device, in the torque phase before entering the inertia phase, the engagement pressure of the engagement clutch is increased to the engagement clutch capacity that does not shift to an unintended inertia phase during the torque phase, and then waits. Then, the inertia phase is started by engine torque down control that reduces the engine torque step by step. For this reason, when an auto upshift is executed by increasing the vehicle speed while maintaining a predetermined accelerator opening, it is not possible to manage the capacity of the engaged clutch at the start of the inertia phase, and the excess or insufficient capacity of the engaged clutch results in a reduction in gear shifting performance. There was a problem with the decline.

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned problem, and aims to improve shift performance by suppressing excess or deficiency in capacity of a clutch engaged at the start of an inertia phase when an automatic upshift is executed due to an increase in vehicle speed. With the goal.

In order to achieve the above object, the present invention is an upshift control device for an automatic transmission, which includes a drive source for traveling, an automatic transmission, and an AT controller.
When the upshift request is a request for an automatic upshift due to an increase in vehicle speed while maintaining a predetermined accelerator opening, the AT controller performs release pressure control using the release instruction pressure and input pressure control using the engagement instruction pressure. It has a shift progress processing section.
After the auto upshift is started, the upshift gear change progress processing unit executes input pressure control for outputting an engagement instruction pressure for gradually increasing the engagement capacity of the engagement clutch when the preparation phase passes and the torque phase is entered.
When the engagement capacity of the engagement clutch reaches a value lower by a predetermined amount than the torque value Tinp , which is the input torque Tinp before torque reduction, the upper limit of the output torque from the drive source for running is reduced stepwise toward the torque value Tinp. After that, the pre-torque down control for outputting a torque down instruction to gradually decrease is started.
When the torque phase shifts to the inertia phase and the start of the inertia phase is detected, the pre-torque down control ends.

As a result, when an automatic upshift is executed due to an increase in vehicle speed, it is possible to suppress excess or deficiency in the capacity of the engaged clutch at the start of the inertia phase, thereby achieving an improvement in shift performance.

1 is an overall system diagram showing an engine vehicle equipped with an automatic transmission to which the upshift control device of Embodiment 1 is applied; FIG. 1 is a skeleton diagram showing an example of an automatic transmission to which the upshift control device of Embodiment 1 is applied; FIG. FIG. 2 is an engagement chart showing engagement states of friction elements for shifting in each speed stage in an automatic transmission to which the upshift control device of the first embodiment is applied; 1 is a shift map diagram showing an example of a shift map in an automatic transmission to which the upshift control device of Embodiment 1 is applied; FIG. 4 is a flow chart showing the flow of auto upshift control processing executed by the AT controller of the first embodiment; 4 is a time chart showing details of auto upshift control processing executed by the AT controller of the first embodiment; 4 is a time chart showing characteristics of accelerator opening APO, gear stage position GP, gear ratio GearRatio, command release pressure, command engagement pressure, engine torque ENGTRQ, and front and rear G when auto upshift is executed.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the upshift control apparatus of the automatic transmission of this invention is demonstrated based on Example 1 shown in drawing.

First, the structure of Example 1 is demonstrated.
The upshift control device in the first embodiment is applied to an engine vehicle equipped with an automatic transmission having 9 forward speeds and 1 reverse speed. Hereinafter, the configuration of the first embodiment will be described by dividing it into "overall system configuration", "detailed configuration of automatic transmission", and "automatic upshift control processing configuration".

[Overall system configuration]
FIG. 1 shows an engine vehicle equipped with an automatic transmission to which the upshift control device of the first embodiment is applied. The overall system configuration will be described below with reference to FIG.

The drive system of the engine vehicle includes an engine 1, a torque converter 2, an automatic transmission 3, a propeller shaft 4, and driving wheels 5, as shown in FIG. A control valve unit 6 including a spool valve, a hydraulic circuit, a solenoid valve, and the like is attached to the automatic transmission 3 . An actuator provided in this control valve unit 6 operates upon receiving a control command from the AT controller 10 .

The control system of the engine vehicle includes an AT controller 10, an engine controller 11, and a CAN communication line 12, as shown in FIG.

The AT controller 10 receives signals from a turbine shaft speed sensor 13, an output shaft speed sensor 14, an ATF oil temperature sensor 15, an accelerator opening sensor 16, an engine speed sensor 17, an inhibitor switch 18, and the like.

A turbine shaft rotation speed sensor 13 detects the turbine rotation speed of the torque converter 2 (=transmission input shaft rotation speed) and sends a signal of the turbine shaft rotation speed Nt to the AT controller 10 . The output shaft rotation speed sensor 14 detects the transmission output shaft rotation speed (=vehicle speed VSP) of the automatic transmission 3 and sends a signal of the output shaft rotation speed No (VSP) to the AT controller 10 . An ATF oil temperature sensor 15 detects the temperature of ATF (automatic transmission oil) and sends a signal of ATF oil temperature TATF to AT controller 10 . The accelerator opening sensor 16 detects the accelerator opening due to the driver's accelerator operation and sends a signal of the accelerator opening APO to the AT controller 10 . An engine speed sensor 17 detects the speed of the engine 1 and sends a signal of the engine speed Ne to the AT controller 10 . The inhibitor switch 18 detects the range position selected by the driver's selection operation on the select lever 19 and sends a range position signal to the AT controller 10 .

The AT controller 10 performs shift control according to the following basic shift pattern by monitoring changes in the driving point due to the vehicle speed VSP and the accelerator opening APO.
1. Auto upshift (by increasing the vehicle speed while maintaining the accelerator opening).
2. Foot release upshift (by accelerator foot release operation).
3. Foot return upshift (by accelerator return operation).
4. Power-on downshift (due to vehicle speed reduction while maintaining accelerator opening).
5. Small-opening sudden downshift (due to small accelerator operation amount).
6. Large-opening sudden downshift (depending on the amount of accelerator operation: "Kickdown").
7. Soft downshift (due to gentle accelerator operation and vehicle speed increase).
8. Coast downshift (due to vehicle speed drop when accelerator foot is released).

The engine controller 11 performs torque reduction control and the like through coordinated control with transmission control in addition to various controls for the engine alone. connected through Therefore, when the AT controller 10 issues a request for torque information, information on the estimated engine torque Te and turbine torque Tt is sent from the engine controller 11 to the AT controller 10 . Further, when the AT controller 10 issues a torque down request, control is executed to reduce the torque of the engine 1 according to the torque down amount and gradient according to the torque down request. The torque down request includes, for example, a slow torque down request by throttle valve closing control and a fast torque down request by, for example, engine retard control.

[Detailed configuration of automatic transmission]
FIG. 2 is a skeleton diagram showing an example of the automatic transmission 3 to which the upshift control device of the first embodiment is applied, FIG. 1 shows an example of a shift map of . The detailed configuration of the automatic transmission 3 will be described below with reference to FIGS. 2 to 4. FIG.

As shown in FIG. 2, the automatic transmission 3 includes, as planetary gears constituting a gear train, a first planetary gear PG1, a second planetary gear PG2, and a third planetary gear PG2 in order from the input shaft IN toward the output shaft OUT. It has a planetary gear PG3 and a fourth planetary gear PG4.

The first planetary gear PG1 is a single pinion type planetary gear, and has a first sun gear S1, a first carrier C1 that supports a pinion that meshes with the first sun gear S1, and a first ring gear R1 that meshes with the pinion.

The second planetary gear PG2 is a single pinion type planetary gear, and has a second sun gear S2, a second carrier C2 that supports a pinion that meshes with the second sun gear S2, and a second ring gear R2 that meshes with the pinion.

The third planetary gear PG3 is a single pinion type planetary gear, and has a third sun gear S3, a third carrier C3 supporting a pinion that meshes with the third sun gear S3, and a third ring gear R3 that meshes with the pinion.

The fourth planetary gear PG4 is a single pinion type planetary gear, and has a fourth sun gear S4, a fourth carrier C4 supporting a pinion that meshes with the fourth sun gear S4, and a fourth ring gear R4 that meshes with the pinion.

The automatic transmission 3, as shown in FIG. 2, includes an input shaft IN, an output shaft OUT, a first connecting member M1, a second connecting member M2, and a transmission case TC. A first brake B1, a second brake B2, a third brake B3, a first clutch K1, a second clutch K2, and a third clutch K3 are provided as friction elements to be engaged/released by shifting. there is

The input shaft IN is a shaft to which driving force from the engine 1 is input via the torque converter 2, and is always connected to the first sun gear S1 and the fourth carrier C4. The input shaft IN is detachably connected to the first carrier C1 via the second clutch K2.

The output shaft OUT is a shaft that outputs a variable drive torque to the driving wheels 5 via the propeller shaft 4 and a final gear (not shown), and is always connected to the third carrier C3. The output shaft OUT is detachably connected to the fourth ring gear R4 via the first clutch K1.

The first connecting member M1 is a member that always connects the first ring gear R1 of the first planetary gear PG1 and the second carrier C2 of the second planetary gear PG2 without intervening a frictional element. The second connecting member M2 constantly connects the second ring gear R2 of the second planetary gear PG2, the third sun gear S3 of the third planetary gear PG3, and the fourth sun gear S4 of the fourth planetary gear PG4 without intervening friction elements. is a member to

The first brake B1 is a friction element capable of locking the rotation of the first carrier C1 with respect to the transmission case TC. The second brake B2 is a friction element capable of locking the rotation of the third ring gear R3 with respect to the transmission case TC. The third brake B3 is a friction element capable of locking the rotation of the second sun gear S2 with respect to the transmission case TC.

The first clutch K1 is a friction element that selectively connects between the fourth ring gear R4 and the output shaft OUT. The second clutch K2 is a friction element that selectively connects between the input shaft IN and the first carrier C1. The third clutch K3 is a frictional element that selectively connects between the first carrier C1 and the second connecting member M2.

FIG. 3 shows an engagement table for achieving 9 forward speeds and 1 reverse speed in the D range by a combination of simultaneous engagement of three of the six friction elements in the automatic transmission 3 . Hereinafter, based on FIG. 3, a description will be given of a shift configuration that establishes each shift stage.

The first speed (1st) is achieved by simultaneously engaging the second brake B2, the third brake B3 and the third clutch K3. The second speed (2nd) is achieved by simultaneously engaging the second brake B2, the second clutch K2 and the third clutch K3. The 3rd speed (3rd) is achieved by simultaneously engaging the second brake B2, the third brake B3 and the second clutch C2. The fourth speed (4th) is achieved by simultaneously engaging the second brake B2, the third brake B3 and the first clutch K1. The fifth speed (5th) is achieved by simultaneously engaging the third brake B3, the first clutch K1 and the second clutch K2. The first to fifth gears described above are underdrive gears with reduction gear ratios exceeding one.

The sixth speed (6th) is achieved by simultaneously engaging the first clutch K1, the second clutch K2 and the third clutch K3. This sixth gear is a direct gear with a gear ratio of 1.

The seventh speed (7th) is achieved by simultaneously engaging the third brake B3, the first clutch K1 and the third clutch K3. The eighth speed (8th) is achieved by simultaneously engaging the first brake B1, the first clutch K1 and the third clutch K3. The ninth speed (9th) is achieved by simultaneously engaging the first brake B1, the third brake B3 and the first clutch K1. The seventh to ninth speeds described above are overdrive speeds with an increasing gear ratio of less than one.

Furthermore, when performing an upshift to an adjacent gear stage among the gear stages from the first gear to the ninth gear, or when performing a downshift, as shown in FIG. It is configured. In other words, shifting to an adjacent shift speed is achieved by releasing one friction element and engaging one friction element while maintaining engagement of two friction elements out of the three friction elements. .

A reverse speed (Rev) by selecting the R range position is achieved by simultaneously engaging the first brake B1, the second brake B2 and the third brake B3. When the N range position and the P range position are selected, all of the six friction elements B1, B2, B3, K1, K2 and K3 are released.

The AT controller 10 stores and sets a shift map as shown in FIG. This shift map is followed. That is, when the operating point (VSP, APO) at that time crosses the upshift line indicated by the solid line in FIG. 4, an upshift request is issued. Also, when the operating point (VSP, APO) crosses the downshift line indicated by the dashed line in FIG. 4, a downshift request is issued.

In the following description, as a shift pattern, as shown in the characteristic framed by the arrow in FIG. ” is handled. For example, in the case of an auto-upshift by switching from 1st gear to 2nd gear, the second clutch K2 is a "closed clutch" that shifts from the released state to the closed state, and the third brake B3 changes from the closed state to the closed state. It is a "release clutch" that transitions to the released state. For example, in the case of an auto-upshift by switching from the 2nd gear to the 3rd gear, the third brake B3 is the "engagement clutch" that shifts from the released state to the engaged state, and the third clutch K3 shifts from the engaged state to the engaged state. It is a "release clutch" that transitions to the released state.

[Auto upshift control processing configuration]
FIG. 5 is a flow chart showing the flow of auto upshift control processing executed by the AT controller 10 of the first embodiment (upshift gear change progress processing section). Each step in FIG. 5 showing the configuration of the automatic upshift control processing will be described below. The flow chart of FIG. 5 is started by an automatic upshift request, and ends when the upshift process is completed and the gear shifts to the next gear stage.

In step S1, when the torque phase is started, or when it is determined in step S4 that the engagement clutch torque TAPL has not reached the target engagement clutch torque Tapl1, the engagement clutch torque TAPL is increased at the target gradient Tra1. , go to step S2.

Here, as shown in FIG. 6, the "torque phase" is started at time t1 by an UP shift instruction, and after the preparation phase has passed until time t2, generation of the clutch torque TAPL is confirmed. be started. In the preparation phase, the engagement command pressure is increased in steps for a short time from time t1 to ensure the oil passage to the engagement clutch and the filling of the oil chamber. As shown in Fig. 6, "increase in engagement clutch torque TAPL at target gradient Tra1" means that the engagement instruction pressure characteristic from time t2 to time t3, when engagement clutch torque TAPL is generated, is defined as a rising gradient with a high inclination angle. This is achieved by

In step S2, following the rise of the engagement clutch torque TAPL at the target gradient Tra1 in step S1, the input torque TD1 after torque reduction during the inertia phase (limit torque after ignition timing retardation) is calculated, and the process proceeds to step S3. move on.

Here, as shown in FIG. 6, the "input torque TD1" is estimated when the engine torque is limited in a stepwise manner by a torque down instruction by retarding the ignition timing from time t5 to time t6 during the inertia phase. Refers to the input torque to the engagement clutch.

In step S3, following the calculation of the input torque TD1 after torque reduction during the inertia phase in step S2, the target engagement clutch torque Tapl1 is calculated from the input torque Tinp before torque reduction and the input torque TD1 after torque reduction, Go to step S4.

Here, as shown in FIG. 6, the "target engagement clutch torque Tapl1" is set based on the torque difference TGap (=Tinp-TD1) between the input torques Tinp and TD1 such that Tapl1≧TGap. Note that the torque difference TGap between the input torque Tinp before the torque reduction and the input torque TD1 after the torque reduction indicates that the upshift progresses more rapidly as the torque difference TGap increases. determine speed.

In step S4, following the calculation of the target engagement clutch torque Tapl1 in step S3, it is determined whether or not the engagement clutch torque TAPL has reached the target engagement clutch torque Tapl1. If YES (TAPL has reached Tapl1), proceed to step S5, and if NO (TAPL has not reached Tapl1), return to step S1.

Here, the timing at which the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1 is the timing of time t3 during the torque phase, as shown in FIG. The timing of this time t3 is the timing at which the inertia phase actually starts during the period from time t3 to inertia phase start detection time t4.

In step S5, following the determination in step S4 that TAPL has reached Tapl1, pre-torque down control is started, and the process proceeds to step S6.

Here, "pre-torque down control" refers to the engine torque down that is executed in advance before the start of the inertia phase so as to promote the progress of gear shifting from the middle of the torque phase until the start of the inertia phase is detected. Control. In the pre-torque down control, as shown in FIG. 6, at time t3, the torque down instruction is stepped down to the vicinity of the input torque Tinp before torque down, and gradually decreases from time t3 to inertia phase start detection time t5. Control is performed to reduce the torque down instruction on the gradient.

In step S6, following the start of the pre-torque down control in step S5, the engagement clutch torque is increased at a gradient Tra2 corresponding to the torque difference TGap, and the process proceeds to step S7.

Here, "increase in engagement clutch torque TAPL at gradient Tra2" means that, as shown in FIG. This is achieved by having a lower rising gradient than

In step S7, it is determined whether or not the elapsed time from the increase in engagement is equal to or less than a threshold, following the increase in engagement at gradient Tra2 in step S6 or the non-detection of the start of the inertia phase in step S9. If YES (engagement instruction rise start elapsed time≦Tra3 correction start time threshold), proceed to step S9, and if NO (engagement instruction rise start elapsed time>Tra3 correction start time threshold), proceed to step S8.

Here, the "engagement instruction rise start elapsed time" refers to the elapsed time from the engagement instruction rise start time t2, as shown in FIG. As shown in FIG. 6, the "Tra3 correction start time threshold" is set to the limit waiting time from the start of the engagement instruction rise to the start of the inertia phase. Therefore, as shown in FIG. 6, when it is determined that the engagement instruction increase start elapsed time≦Tra3 correction start time threshold until the inertia phase start detection time t5, the engagement clutch torque increases at the gradient Tra2 corresponding to the torque difference TGap. It is said that

In step S8, following the judgment in step S7 that the elapsed time to start increasing the engagement instruction>Tra3 correction start time threshold value, the engagement clutch torque is increased at a gradient obtained by adding the correction value Tra3 to the gradient Tra2, and step S9. proceed to

Here, the "correction value Tra3" is set to a value that increases the rate of increase of the engagement clutch torque, speeds up the speed change, and prompts the start of the inertia phase.

In step S9, it is judged that the engagement instruction increase start elapsed time>Tra3 correction start time threshold in step S7, or following the engagement clutch torque increase at the gradient Tra2+Tra3 in step S8, the inertia phase is started. It is determined whether or not it has been detected. If YES (the start of the inertia phase is detected), the process proceeds to step S10, and if NO (the start of the inertia phase is not detected), the process returns to step S7.

Here, "inertia phase start detection" monitors the actual gear ratio based on the ratio of the input rotation speed and the output rotation speed of the automatic transmission 3, and shifts the gear ratio after the upshift from the gear ratio before the upshift to the gear after the upshift. This is done by detecting the timing at which the gear ratio starts to change. That is, as shown in FIG. 6, when the gear ratio change width exceeds the inertia phase start determination threshold at time t5, it is detected that the inertia phase has started. Therefore, the inertia phase actually starts at time t4 due to the gear ratio change, but there is a detection delay.

In step S10, following the determination that the start of the inertia phase has been detected in step S9, the pre-torque down control started in step S5 is ended, and the process proceeds to step S11.

In step S11, following the end of the pre-torque down control in step S10, torque down control during the normal inertia phase is started, and the engagement clutch torque TAPL is increased at the target gradient Tra4 during the inertia phase, before proceeding to step S12.

Here, "normal inertia phase torque reduction control" means that the torque reduction instruction is stepwise decreased at the inertia phase start detection time t5, and the torque reduction instruction is given with a gradually increasing gradient until the inertia phase end detection time t6. . Then, at the inertia phase end detection time t6, the torque down instruction is increased stepwise, returned to the vicinity of the input torque Tinp before torque down from time t6 to the inertia phase end time t7, and torque down control is performed at time t7. Refers to the control that terminates. "Increase in engagement clutch torque TAPL at target gradient Tra4 during inertia phase", as shown in Fig. 6, means that the instructed engagement pressure characteristic from time t5 to inertia phase end time t7 will be lower than the rising gradient in the torque phase. This is achieved by having a low gradient.

In step S12, following the start of torque reduction control during the normal inertia phase in step S11 and the increase of the engagement clutch torque TAPL at the target gradient Tra4 during the inertia phase, normal processing (shift end processing) is executed thereafter, and the process proceeds to the end. move on.

Here, as shown in FIG. 6, the "normal processing" means that from the inertia phase end time t7 to the gear shift end time t9, the engagement clutch torque TAPL is increased at the target gradient during the end phase, and the engagement clutch is fully engaged. refers to the control that directs In other words, the engagement instruction pressure characteristics from the inertia phase end time t7 to the shift end time t9 are divided into the rising gradient Tra5 (>Tra4) from time t7 to time t8 and the rising gradient Tra6 (>Tra5) from time t8 to time t9. This is achieved by Regarding release clutch torque control and release instruction pressure control of the release clutch that are controlled simultaneously with the engagement clutch, normal processing in upshift control (processing to remove release clutch torque before the start of the inertia phase) is performed.

Next, the actions of the first embodiment will be described separately for "automatic upshift control processing action", "automatic upshift progress processing action", and "characteristic actions in automatic upshift control".

[Auto upshift control processing action]
The operation of the automatic upshift control process will be described below with reference to the flow chart of FIG.
The auto upshift control is started by an UP shift instruction, and after the preparation phase has passed, the torque phase is started by confirming the generation of the engagement clutch torque TAPL. When the torque phase is started, the flow of step S1→step S2→step S3→step S4 is repeated until the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1. In step S1, control is performed to increase the engagement clutch torque TAPL with the target gradient Tra1. In step S2, the input torque TD1 after torque reduction during the inertia phase is calculated, and in step S3, the target engagement clutch torque Tapl1 is calculated from the input torque Tinp before torque reduction and the input torque TD1 after torque reduction.

Then, when the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1 due to the increase in the engagement clutch torque TAPL, the process proceeds from step S4 to step S5→step S6. In step S5, pre-torque down control is started following the determination in step S4 that TAPL has reached Tapl1. In step S6, simultaneously with the start of pre-torque down control in step S5, control for increasing the engagement clutch torque at a gradient Tra2 corresponding to the torque difference TGap is started.

From step S6, the process proceeds to step S7→step S9. While the elapsed time from the start of increasing the engagement clutch torque is equal to or less than the threshold value and it is determined that the start of the inertia phase is not detected, step S7→step S9 is performed. The flow to step S9 is repeated. Therefore, during this period, the engagement clutch torque TAPL is increased at the gradient Tra2. However, if the elapsed time from the start of increasing the engagement clutch torque exceeds the threshold while it is still determined that the inertia phase start has not been detected, the flow of step S7→step S8→step S9 is repeated. Therefore, when the elapsed time exceeds the threshold, the applied clutch torque TAPL is increased by switching from the gradient Tra2 to the gradient (Tra2+Tra3).

When the start of the inertia phase is detected in step S9, the process proceeds from step S9 to step S10→step S11. In step S10, the pre-torque down control started in step S5 is ended, and the torque down control during the next normal inertia phase is started according to the torque down instruction. In step S11, torque reduction control during the normal inertia phase is started, and control for increasing the engagement clutch torque TAPL at the target gradient Tra4 during the inertia phase is also started.

From step S11, the process proceeds to step S12→end, and in step S12, during the end phase from the end of the inertia phase to the end of shifting, the engagement clutch torque TAPL is increased at the target gradient to move the engagement clutch toward the fully engaged state. control is performed.

In this way, when there is an auto-upshift request, during the torque phase, when the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1, torque increase control and pre-torque down control of the engagement clutch are executed simultaneously. be done. By using these two simultaneous controls together, the excessive engagement capacity due to the delay in detecting the start of the inertia phase is reduced in advance by pre-torque down control, so that the engagement capacity of the engagement clutch at the start of the inertia phase (= clutch torque) is set to the target value.

During the inertia phase, the torque increase control of the engagement clutch and the torque reduction control during the normal inertia phase are simultaneously executed. By using these two controls in parallel, the shift progress speed is set to the target speed during the inertia phase.

[Auto upshift progress processing action]
FIG. 7 is a time chart showing each characteristic in the auto upshift progress process. The action of the auto-upshift progress processing will be described below with reference to FIG.

At time t1, as shown in the frame of A in FIG. 4, while driving, the vehicle crosses the upshift line when the vehicle speed VSP increases due to a decrease in running resistance, etc., although the predetermined accelerator opening APO is maintained. Then, an upshift request is issued. When an upshift request is issued, the preparation phase Ph1, the torque phase Ph2, the inertia phase Ph3, and the end phase Ph4 are passed, and the auto upshift ends. The preparation phase Ph1, the torque phase Ph2, the inertia phase Ph3, and the end phase Ph4 will be separately described below.

(Preparation Phase Ph1)
The preparation phase Ph1 is a section to prepare for engagement of the engagement clutch and release of the release clutch from time t1 to time t2.

The release command pressure in the preparation phase Ph1 is stepwise decreased at the upshift request time t1, and the release wait time from the lowered command release pressure position to the preparation phase end time t2 is further decreased. remain as is.

The instructed engagement pressure in the preparation phase Ph1 is stepwise increased at the upshift request time t1, and the increased instructed position is maintained until the time t1'. At the time t1', the pressure is decreased in a stepwise manner, and thereafter, the decreased engagement instruction pressure is maintained until the preparation phase end time t2.

Note that no torque down instruction is issued in the preparation phase Ph1. The G before and after the preparation phase Ph1 is also constant from the preparation phase start time t1 to the preparation phase end time t2.

(Torque phase Ph2)
Torque phase Ph2 is a section in which the capacity of the engaged clutch that is engaged after shifting increases from time t2 to time t3.

The command release pressure in the torque phase Ph2 decreases to zero from the torque phase start time t2 to the torque phase end time t4.

The instructed engagement pressure in the torque phase Ph2 is increased so that the increasing gradient of the engagement clutch torque TAPL is Tra1 from the torque phase start time t2 to the time t3 when the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1. . Subsequently, from time t3 to torque phase end time t4, the instructed engagement pressure is increased so that the gradient of increase in engagement clutch torque TAPL is Tra2.

A torque down instruction in torque phase Ph2 is not issued from torque phase start time t2 to time t3. However, at time t3, the torque down command is decreased to near the input torque Tinp before torque down, and then pre-torque down control is started to decrease the torque down command at a predetermined decrease gradient.

Note that the front and rear G in the torque phase Ph2 decreases with a gentle oblique gradient from the torque phase start time t2 to the torque phase end time t4 due to the replacement of the release capacity and the engagement capacity.

(inertia phase Ph3)
Inertia phase Ph3 is a section in which the gear ratio shifts from the pre-shift gear ratio to the post-shift gear ratio from time t4 to time t7. Note that the command release pressure in the inertia phase Ph3 is kept at zero.

The instructed engagement pressure in the inertia phase Ph3 continues control so that the increasing gradient of the engagement clutch torque TAPL from time t3 is Tra2 from the inertia phase start time t4 to the inertia phase start detection time t5. From the time t5 to the inertia phase end time t7, the rising gradient of the engagement clutch torque TAPL is suppressed so as to be Tra4.

The torque down instruction in the inertia phase Ph3 continues the pre-torque down control from time t3 from the inertia phase start time t4 to the inertia phase start detection time t5. Then, at time t5, the input torque is reduced stepwise to TD1 after torque reduction, and torque reduction control during the normal inertia phase is started. That is, after the torque down instruction is gradually increased from time t5 to inertia phase end detection time t6, the torque is increased stepwise at time t6. Then, from time t6 to inertia phase end time t7, the torque is increased at a predetermined rising gradient, and at time t7, the torque down instruction is returned to zero.

The longitudinal G in the inertia phase Ph3 maintains a flat characteristic after increasing at the inertia phase start time t4.

(end phase Ph4)
The end phase Ph4 is a section in which the capacity of the engagement clutch is increased to the full engagement capacity from time t7 to time t9. Note that the command release pressure in the end phase Ph4 is maintained at zero.

The instructed engagement pressure in the end phase Ph4 increases the gradient of increase of the engagement clutch torque TAPL from time t7 to time t8 so that the gradient of increase of the engagement clutch torque TAPL becomes Tra5. From time t8 to shift end time t9, the increase gradient of the engagement clutch torque TAPL is further increased to Tra6, and at time t9, the clutch torque TAPL is set to the engagement instruction pressure that achieves the fully engaged state.

The torque down instruction in the end phase Ph4 maintains the torque down instruction zero. The front and rear G in the end phase Ph4 shows a characteristic that it decreases slightly at the end phase start time t7 and then gradually increases in the acceleration direction.

In this way, the auto upshift is a shift pattern that prioritizes moderate changes in acceleration/deceleration due to shift over shift response because the driver keeps the accelerator opening APO constant. On the other hand, by pre-torque down control from time t3 to time t5, the excessive capacities of the engaged clutch due to the delay in detection of the start of the inertia phase are reduced by pre-torque down control in advance. Therefore, the engagement clutch torque TAPL at the time when the start of the inertia phase is detected is controlled to an appropriate torque value that substantially matches the input torque Tinp before the torque reduction.

"Characteristic Action in Auto Upshift Control"
First, an upshift is a shift control that lowers the transmission input rpm and converges to the gear ratio of the High gear stage. Control of the engagement clutch is important because it prompts. The inventors of the present invention have found that during an auto-upshift due to an increase in vehicle speed while maintaining a predetermined accelerator opening, there is a rebound in shift performance due to insufficient management of the engagement clutch torque at the start of the inertia phase. I found out.

That is, the inertia phase in auto upshift is
(input torque + release clutch capacity) < engagement clutch capacity (1)
Start/progress at the stage where Ideally, the release clutch capacity should be 0 Nm or less at the timing when the inertia phase (rotation change) starts. Therefore, in order to reliably shift to the inertia phase, it is necessary to create a state in which the engagement clutch capacity exceeds (input torque + release clutch capacity).

Then, when the inertia phase is started without the above relationship (1) being established, there is a concern that the following rebound in shift performance will occur.
(A) If the engagement clutch capacity is excessive in the torque phase before the start of the inertia phase, the engine load will increase and the transmission input speed will drop sharply, resulting in a large change in vehicle behavior due to deceleration in the torque phase. Become. After the inertia phase starts, the speed at which the upshift progresses is faster than intended, and the torque step at the end of the inertia phase becomes large.
(B) If the engagement clutch capacity is insufficient at the start of the inertia phase, the engine load becomes small and racing (raising of the turbine speed) occurs, which delays the transition to the inertia phase. After the inertia phase starts, the progress speed of the upshift becomes slower than intended, and the shift response deteriorates.

In this way, in order to obtain good gear shift performance, it is important to prevent excess or deficiency of the engagement clutch capacity from occurring at the start of the inertia phase. On the other hand, if an attempt is made to establish the above relationship (1) only by raising the engagement clutch, an excess engagement clutch capacity will occur at the start of the inertia phase. On the other hand, if the engagement clutch capacity is maintained before the start of the inertia phase and an attempt is made to achieve the above relationship (1) by engine torque reduction (input torque control), the engagement clutch capacity becomes insufficient at the start of the inertia phase. .

Therefore, the inventors of the present invention have focused on the fact that if the increase in the engagement capacity of the engagement clutch and the engine torque down control that induces the inertia phase are used together, it is possible to suppress the excess or deficiency of the engagement clutch capacity at the start of the inertia phase. did.

In the first embodiment, the upshift gear change progress processing section (FIG. 5) of the AT controller 10 gradually increases the engagement clutch torque TAPL after the start of the auto upshift and after the preparation phase and the torque phase. Execute input pressure control that outputs the indicated pressure. When the engagement clutch torque TAPL reaches a torque value lower than the input torque Tinp by a predetermined amount, the upper limit value of the output torque from the engine 1 is stepwise decreased toward the input torque Tinp, and then a torque down instruction is given to decrease gradually. Starts output pre-torque down control. When the torque phase shifts to the inertia phase and the start of the inertia phase is detected, the pre-torque down control ends.

That is, the engine torque is reduced by the pre-torque down control before the inertia phase is started, thereby suppressing the occurrence of excessive capacities of the engaged clutch due to delay in detection of the start of the inertia phase. Pre-torque down control is started after waiting for the engagement clutch torque TAPL to reach a torque value close to the input torque Tinp. occurrence is suppressed. Therefore, even if there is a delay in detecting the start of the inertia phase, the engagement clutch torque TAPL at the time of detection of the start of the inertia phase is approximately equal to the input torque Tinp before the torque reduction, as shown in the characteristics within the frame of arrow B in FIG. It is managed to match the proper torque value.

Therefore, when an automatic upshift is executed due to an increase in vehicle speed, an improvement in shift performance is achieved by suppressing excess or deficiency in the capacity of the engaged clutch at the start of the inertia phase.

In the first embodiment, the target engagement clutch torque Tapl1 is set to a value equal to or greater than the torque difference TGap between the input torque Tinp before torque reduction and the input torque TD1 after torque reduction during the inertia phase. When the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1, pre-torque down control is started.

That is, since the introduction region to the inertia phase is determined by the timing at which the pre-torque down control is started, it is preferable to match the start timing of the pre-torque down control with the speed change progress speed during the inertia phase. On the other hand, the torque difference TGap between the input torque Tinp and the input torque TD1 serves as estimated information of the shift progress speed during the inertia phase.

Therefore, by making the start timing of the pre-torque down control appropriate, it is possible to prevent the occurrence of changes in the behavior of the vehicle and the occurrence of racing due to deceleration caused by excess or insufficient capacity of the engagement clutch at the start of the inertia phase.

In the first embodiment, the engagement clutch torque TAPL of the engagement clutch is increased at the first rising gradient Tra1 until the engagement clutch torque TAPL of the engagement clutch reaches the target engagement clutch torque Tapl1 after entering the torque phase. When the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1, it is raised by a second elevation gradient Tra2 whose gradient angle is smaller than the first elevation gradient Tra1.

That is, when the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1, it is increased by the second slope of increase Tra2 (<the slope of first slope Tra1), so that in the region where the torque phase shifts to the inertia phase, the shift progress speed is slow. controlled by

Therefore, the range of increase in the engagement clutch torque TAPL from the start of the pre-torque down control until the start of the inertia phase is detected is kept small, and the management accuracy of the engagement clutch torque TAPL at the start of the inertia phase is improved.

In the first embodiment, when the elapsed time from when the engagement clutch torque TAPL of the engagement clutch starts increasing exceeds the threshold, the engagement capacity of the engagement clutch is increased at a gradient obtained by adding the correction value Tra3 to the second gradient of increase Tra2. .

That is, as described above, when the second slope of increase Tra2 is used, the shift speed is controlled to be slow in the region where the torque phase shifts to the inertia phase, which may delay the start of the inertia phase and reduce the shift response. be. On the other hand, when the predetermined time threshold is exceeded, the engagement capacity of the engagement clutch is increased by a gradient obtained by adding the correction value Tra3 to the second gradient of increase Tra2, thereby prompting detection of the start of the inertia phase.

Therefore, when it is predicted that the start of the inertia phase will be delayed before the start of the inertia phase is detected, the shift response is prevented from deteriorating.

In the first embodiment, when the pre-torque down control is terminated by detecting the start of the inertia phase, the torque down control during the inertia phase is started following the pre-torque down control.

That is, if the speed at which the upshift progresses during the inertia phase is faster than the target, the torque step at the end of the inertia phase becomes large. On the other hand, by promptly starting the torque down control during the inertia phase following the pre-torque down control, it is possible to control the advancing speed of the upshift during the inertia phase to a target speed.

Therefore, as shown in the characteristics within the frame of arrow C in FIG. 7, the torque step difference between the front and rear G at the end of the inertia phase is suppressed to be small, and the sense of discomfort given to the driver is suppressed.

Next, the effect of Example 1 is demonstrated. The upshift control device for the automatic transmission 3 has the following effects.

(1) A drive source for running (engine 1), an automatic transmission 3 connected to the drive source for running (engine 1) and having a plurality of shift stages and a plurality of friction elements, and a plurality of and an AT controller 10 that performs upshifting by replacement of the friction elements, releasing the release clutch and engaging the engagement clutch.
In this upshift control device for the automatic transmission 3, the AT controller 10, when the upshift request is a request for an auto upshift due to an increase in vehicle speed while maintaining a predetermined accelerator opening, releases pressure by releasing instruction pressure. It has an upshift shift progress processing unit (Fig. 5) that performs control and input pressure control based on the engagement instruction pressure.
After the auto upshift is started, the upshift shift progress processing section (Fig. 5) enters the torque phase after passing the preparation phase. Execute the input pressure control that outputs
When the engagement capacity of the engagement clutch (engagement clutch torque TAPL) reaches a value lower than the input torque Tinp by a predetermined amount, the upper limit of the output torque from the drive source for running (engine 1) is reduced stepwise toward the input torque Tinp. After that, the pre-torque down control for outputting a torque down instruction to gradually decrease is started.
When the torque phase shifts to the inertia phase and the start of the inertia phase is detected, the pre-torque down control ends.
Therefore, when an automatic upshift is executed due to an increase in vehicle speed, it is possible to suppress excess or insufficient capacity of the engaged clutch at the start of the inertia phase, thereby achieving improvement in shift performance.

(2) The upshift shift progress processing section (Fig. 5) sets the target engagement clutch torque Tapl1 as a value equal to or greater than the torque difference TGap between the input torque Tinp before torque reduction and the input torque TD1 after torque reduction during the inertia phase. do.
When the engagement capacity of the engagement clutch (engagement clutch torque TAPL) reaches the target engagement clutch torque Tapl1, pre-torque down control is started.
For this reason, in addition to the effect of (1), by making the start timing of pre-torque down control appropriate, at the start of the inertia phase, the behavior of the vehicle changes due to deceleration caused by the excess or deficiency of the capacity of the engaged clutch, and the occurrence of racing. occurrence can be prevented.

(3) The upshift shift progress processing section (Fig. 5) controls the engagement capacity of the engagement clutch until the engagement capacity of the engagement clutch (engagement clutch torque TAPL) reaches the target engagement clutch torque Tapl1 after entering the torque phase. Ascend at the first ascending gradient Tra1.
When the engagement capacity of the engagement clutch reaches the target engagement clutch torque Tapl1, the torque is raised by a second elevation gradient Tra2 whose gradient angle is smaller than the first elevation gradient Tra1.
Therefore, in addition to the effect of (2), it is possible to improve the management accuracy of the engagement clutch torque TAPL at the start of the inertia phase.

(4) The upshift shift progress processing section (Fig. 5) sets the second rising gradient Tra2 to the correction value Increase the engagement capacity of the engagement clutch with the gradient with Tra3 added.
Therefore, in addition to the effect of (3), when it is predicted that the start of the inertia phase will be delayed before the start of the inertia phase is detected, it is possible to prevent the shift response from deteriorating.

(5) After the pre-torque down control is terminated by the detection of the start of the inertia phase, the upshift gear change progress processing section (Fig. 5) starts the torque down control during the inertia phase following the pre-torque down control.
Therefore, in addition to the effects of (1) to (4), the difference in torque between the front and rear G at the end of the inertia phase can be kept small, so that the sense of discomfort given to the driver can be suppressed.

The upshift control device for an automatic transmission according to the present invention has been described above based on the first embodiment. However, the specific configuration is not limited to the first embodiment, and design changes and additions are permitted as long as they do not deviate from the gist of the invention according to each claim of the scope of claims.

In the first embodiment, the upshift gear change progress processing section sets the target engagement clutch torque Tapl1 with a value equal to or greater than the torque difference TGap, and starts pre-torque down control when the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1. I gave an example. However, as an upshift shift progress processing unit, the target engagement clutch torque is set based on the input torque before torque reduction, and pre-torque down control is started when the engagement clutch torque reaches the target engagement clutch torque. good.

In the first embodiment, when the engagement clutch torque TAPL reaches the target engagement clutch torque Tapl1, the upshift gear change progress processing section shows a preferable example in which the engagement clutch torque TAPL is increased by a second elevation gradient Tra2 whose gradient angle is smaller than the first elevation gradient Tra1. rice field. However, the upshift progress processing unit may be an example in which the increasing gradient of the applied clutch torque is not changed before and after the applied clutch torque reaches the target applied clutch torque.

In the first embodiment, an example of the automatic transmission 3 with nine forward speeds and one reverse speed is shown as the automatic transmission. However, the automatic transmission may be an automatic transmission having a stepped gear other than nine forward speeds and one reverse speed. Further, in the first embodiment, an example of an upshift control device for an automatic transmission mounted on an engine vehicle has been shown, but the upshift control device is not limited to an engine vehicle, and can be used as an upshift control device for an automatic transmission such as a hybrid vehicle or an electric vehicle. can also be applied.

1 engine (driving source for running)
2 torque converter 3 automatic transmission
B1 1st brake (friction element)
B2 2nd brake (friction element)
B3 3rd brake (friction element)
K1 First clutch (friction element)
K2 Second clutch (friction element)
K3 Third clutch (friction element)
4 Propeller shaft 5 Drive wheel 6 Control valve unit 10 AT controller 11 Engine controller 12 CAN communication line 13 Turbine shaft rotation speed sensor 14 Output shaft rotation speed sensor 15 ATF oil temperature sensor 16 Accelerator opening sensor 17 Engine speed sensor 18 Inhibitor switch 19 Select lever

Claims (5)

a drive source for running;
an automatic transmission connected to the drive source for running and having a plurality of shift stages and a plurality of friction elements;
an AT controller that, when an upshift is requested, executes an upshift by replacing a releasing clutch among the plurality of friction elements and engaging an engaging clutch;
In an upshift control device for an automatic transmission comprising
When the upshift request is a request for an automatic upshift due to an increase in vehicle speed while maintaining a predetermined accelerator opening, the AT controller performs release pressure control using the release instruction pressure and input pressure control using the engagement instruction pressure. having an upshift shift progress processing unit,
After the automatic upshift is started, the upshift gear change progress processing unit performs input pressure control for outputting an engagement instruction pressure for gradually increasing the engagement capacity of the engagement clutch when the preparation phase passes and the torque phase is entered. run,
When the engagement capacity of the engagement clutch reaches a value lower by a predetermined amount than the torque value Tinp , which is the input torque Tinp before torque reduction, the upper limit of the output torque from the drive source for running is increased stepwise toward the torque value Tinp. , and then start pre-torque down control to output a torque down instruction to
An upshift control device for an automatic transmission, wherein the torque phase shifts to the inertia phase, and when the start of the inertia phase is detected, the pre-torque down control is terminated. In the upshift control device for an automatic transmission according to claim 1,
The upshift gear change progress processing unit includes:
performing stepwise torque reduction at the start of the inertia phase,
calculating a torque difference TGap between the torque value Tinp and the torque value TD1 , which is the input torque TD1 after the stepwise torque reduction;
A target engagement clutch torque Tapl1 is set to a value equal to or greater than the torque difference TGap,
An upshift control device for an automatic transmission, wherein the pre-torque down control is started when the engagement capacity of the engagement clutch reaches the target engagement clutch torque Tapl1. In the upshift control device for an automatic transmission according to claim 2,
The upshift shift progress processing unit increases the engagement capacity of the engagement clutch at a first rising gradient until the engagement capacity of the engagement clutch reaches the target engagement clutch torque Tapl1 after entering the torque phase. ,
An upshift control device for an automatic transmission, wherein when the engagement capacity of the engagement clutch reaches the target engagement clutch torque Tapl1, the torque is increased by a second gradient having a smaller gradient angle than the first gradient. In the upshift control device for an automatic transmission according to claim 3,
When the elapsed time from when the engagement capacity of the engagement clutch starts increasing exceeds a threshold value, the upshift shift progress processing unit increases the engagement capacity of the engagement clutch at a gradient obtained by adding a correction value to the second rising gradient. An upshift control device for an automatic transmission, characterized by raising In the upshift control device for an automatic transmission according to any one of claims 1 to 4,
When the pre-torque down control is terminated by detecting the start of the inertia phase, the upshift shift progress processing unit starts the torque-down control during the inertia phase subsequent to the pre-torque down control. machine upshift control device.

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