JP5047738B2 - Control device for automatic transmission for vehicle - Google Patents

Description

  The present invention relates to a control device for an automatic transmission for a vehicle that performs torque down to reduce output torque of a power source in order to reduce a torque pulling shock during a torque phase.

Patent Document 1 discloses an upshift shock reducing device that controls the output torque of a power source in the torque phase in order to reduce the torque pulling shock during the torque phase during upshifting.
Here, the torque pull-in will be described in detail. In the automatic transmission, when the two friction engagement elements are replaced, that is, when the shift is performed by so-called clutch-to-clutch, the release-side friction engagement element is the release-side control means. Even when the operation is suitably performed based on the appropriate hydraulic control of the hydraulic servo by the torque pull-in occurs when the engagement standby hydraulic pressure (the engagement-side hydraulic pressure during the engagement control) is excessive. If this pull-in occurs in the frictional engagement element on the engagement side, tie-up (simultaneous engagement of two frictional engagement elements) occurs even when the release-side hydraulic pressure is appropriate.

In order to achieve a good shift shock, the torque before and after the shift may be changed linearly. However, in the case of a stepped transmission, there are a torque phase and an inertia phase. The phase is a phase in which torque is transferred from the front gear stage to the gear stage after the shift without changing the gear ratio, and the inertia phase is a phase in which rotation is absorbed for switching the gear ratio.
JP 2001-248466 A

In order to reduce the torque pulling shock during the torque phase, it is desirable to determine the timing of torque control (shock mitigation control) in relation to the actual torque pulling.
However, since the torque control timing is determined based on the signal of the hydraulic switch in the above-mentioned Patent Document 1, it is possible to cope with variations from the signal change of the hydraulic switch to the actual capacity change of the friction engagement element. However, the start / end timing of torque control deviates from the optimal timing with respect to the actual torque pull-in, and the torque pull can be increased by performing torque control, or the torque step before and after the torque pull-in can be reduced well. There was a problem that it might not be.

  The present invention has been made in view of the above-described problems, and allows torque reduction for reducing torque pulling shock during the torque phase to be performed at an optimal timing without being affected by variations in hydraulic response. The purpose is to be able to.

Therefore, according to the first aspect of the present invention , in the automatic transmission for a vehicle combined with the power source, in order to reduce the torque pulling shock in the torque phase at the time of shifting, torque reduction is performed to reduce the output torque of the power source. A control device for an automatic transmission for a vehicle, wherein a time when a predetermined time has elapsed from a start time of a torque phase is set as an end time of torque reduction, and the predetermined time is set as a temperature of hydraulic oil of the automatic transmission. It is characterized by including a control timing setting means for increasing the lower the value.

According to a second aspect of the present invention, in a vehicle automatic transmission combined with a power source, a vehicle that performs torque-down to reduce the output torque of the power source in order to reduce a torque pull-in shock in a torque phase during shifting. A control apparatus for an automatic transmission for controlling a time at which a predetermined time has elapsed from a start time of a torque phase as a torque down end time, and making the predetermined time longer as a load of a power source is higher It is characterized by including a time setting means.

According to the above invention, the predetermined time is set in response to the change in the time from the start of the torque phase to the start of the inertia phase due to the difference in the temperature of the hydraulic fluid of the automatic transmission and the load of the power source. change.
Therefore, even if the temperature of the hydraulic oil of the automatic transmission and the load of the power source are different, the torque reduction for reducing the torque pulling shock can be terminated at the optimal timing after the torque phase is started .

According to the third aspect of the present invention, the setting of the torque down end time based on the elapsed time from the start time of the torque phase is canceled when the change in the load of the power source during the shift is greater than or equal to a predetermined value.

According to the above invention, when the change in the load of the power source becomes greater than or equal to a predetermined value, for example, when the accelerator is operated during shifting, the setting of the torque down end time based on the elapsed time from the start time of the torque phase is cancelled .
Therefore, it is possible to suppress the erroneous detection of the start of the torque phase due to the fluctuation of the load of the power source and the occurrence of an error in the setting of the torque down end time based on the measurement of the elapsed time from the torque phase .

According to the fourth aspect of the present invention, the start time of the torque phase is detected based on at least one of a change in the vehicle speed and a change in the input shaft rotation speed of the transmission .
According to the above invention, the start of the torque phase is detected by detecting the change in at least one of the vehicle speed and the input shaft rotational speed (turbine rotational speed) of the transmission accompanying the start of the torque phase, and the end time of the torque reduction is determined. Set.

Since the torque pull-in occurs at the start of the torque phase, the vehicle speed and the input shaft rotation speed show a decreasing change. Therefore, the start of the torque phase can be detected by detecting such a change.
Therefore, the start of the torque phase as a result of the hydraulic control can be detected with high response and high accuracy.

Embodiments of the present invention will be described below.
FIG. 1 shows a drive system of a vehicle in an embodiment. A hydraulic automatic transmission 3 is connected to an output shaft of an engine 1 as a power source via a torque converter 2, and the automatic transmission 3. The drive wheels (not shown) of the vehicle are rotated by the output shaft.
The power source combined with the automatic transmission 3 may be an electric motor in addition to the engine 1, and the power source may be a combination of an engine and an electric motor.

FIG. 2 is a skeleton showing a stepped gear type transmission mechanism portion of the automatic transmission 3.
The transmission mechanism section includes two sets of planetary gears G1, G2, three sets of multi-plate clutches (high clutch H / C, reverse clutch R / C, low clutch L / C), one set of brake bands 2 & 4 / B, One set of multi-plate brakes (low & reverse brake L & R / B) and one set of one-way clutch L / OWC.

The two sets of planetary gears G1 and G2 are simple planetary gears composed of sun gears S1 and S2, ring gears r1 and r2, and carriers c1 and c2, respectively.
The sun gear S1 of the planetary gear set G1 is configured to be connectable to the input shaft IN by a reverse clutch R / C, and is configured to be fixed by a brake band 2 & 4 / B.
The sun gear S2 of the planetary gear set G2 is directly connected to the input shaft IN.

The carrier c1 of the planetary gear set G1 is configured to be connectable to the input shaft IN by a high clutch H / C, while the ring gear r2 of the planetary gear set G2 is a carrier of the planetary gear set G1 by a low clutch L / C. The carrier c1 of the planetary gear set G1 can be fixed by a low & reverse brake L & R / B.
A ring gear r1 of the planetary gear set G1 and a carrier c2 of the planetary gear set G2 are directly and integrally connected to the output shaft OUT.

In FIG. 2, reference numeral 21 denotes an oil pump (hydraulic pump) that is driven by the engine 1 and supplies hydraulic oil to the automatic transmission.
In the speed change mechanism having the above-described configuration, forward 1st to 4th speeds and reverse R are realized by a combination of engagement / release states of the respective clutches and brakes (friction engagement elements) as shown in FIG.

In FIG. 3, the circles indicate the engaged state, and the parts not marked with the symbol indicate that they are in the released state. In particular, the engaged state indicated by the black circle of the low & reverse brake L & R / B at the first speed. Indicates fastening in only one range.
The above engagement / release logic of the friction engagement element is realized by a combination of ON / OFF of the shift solenoid (A) 5 and the shift solenoid (B) 6 inserted in the control valve 4 for shift control shown in FIG. (See FIG. 4).

A line pressure solenoid 7 is inserted into the control valve 4, and the line pressure of the control valve 4 is controlled by the line pressure solenoid 7.
The shift solenoid (A) 5, the shift solenoid (B) 6 and the line pressure solenoid 7 are controlled by an A / T controller 11.
The A / T controller 11 includes a microcomputer, and includes an ATF temperature sensor 12 that detects the temperature of an automatic transmission fluid (hydraulic oil), and an accelerator opening that detects a depression amount APO of an accelerator pedal (not shown). Degree sensor 13, vehicle speed sensor 14 for detecting vehicle running speed VSP, engine speed sensor 15 for detecting rotational speed NE of engine 1, and inhibitor for detecting a range position selected by a driver operating a shift knob (shift lever). A detection signal is input from the switch 16, the turbine sensor 17 that detects the turbine rotational speed NT in the torque converter 2, and the like.

The turbine rotational speed NT corresponds to the input shaft rotational speed of the transmission, and the vehicle speed VSP is proportional to the output shaft rotational speed of the transmission.
The A / T controller 11 sets a target gear stage based on the various detection signals (the driving state of the vehicle), and when the target gear stage and the actual gear stage are different, the shift solenoid (A ) 5, Automatic shift control is performed by controlling the shift solenoid (B) 6 so that the actual gear stage matches the target gear stage.

In addition, the A / T controller 11 and the engine control unit 21 are connected to be able to communicate with each other, and the A / T controller 11 controls the engine down request to reduce the torque pull-in shock in the torque phase at the time of shifting. Output to unit 21.
It is possible to integrate the A / T controller 11 and the engine control unit 21 and control both the engine 1 and the automatic transmission 3 with a single control unit (controller).

  The engine control unit 21 includes a microcomputer, and includes an air flow meter 22 that detects an intake air flow rate QA of the engine 1, a water temperature sensor 23 that detects a cooling water temperature TW of the engine 1, and a throttle in an electronically controlled throttle device 31. In addition to the detection signal of the throttle sensor 25 for detecting the opening degree TVO, the detection signal of the engine rotation sensor 15 is input.

The engine control unit 21 controls the electronic control throttle device 31, the fuel injection valve 32, and the ignition device 33 in accordance with the engine operating state detected based on the various detection signals, and the A / T. When a torque down request signal from the controller 11 is input, torque down control for forcibly reducing the output torque of the engine 1 is executed.
The torque down control executes at least one of ignition timing retard, throttle opening (intake air amount) decrease, cylinder-by-cylinder fuel cut, and air-fuel ratio leaning, thereby reducing the torque of the engine 1. Is forcibly reduced.

When the power source includes an electric motor, the output torque of the power source can be reduced by regenerative brake control of the electric motor.
Here, the output control (function as control timing setting means) of the torque down request signal for reducing the torque pulling shock in the torque phase by the A / T controller 11 will be described in detail according to the flowchart of FIG. .

The routine shown in the flowchart of FIG. 5 is executed every predetermined minute time.
In step S101, it is determined whether a shift determination is being performed (upshift determination is being performed).
When shifting is being determined, a shift request (upshift request) is determined based on a determination that the target gear stage (target gear ratio) is different from the actual gear stage (gear ratio), and then the target gear stage This is the time until the actual gear stage (gear ratio) matches the (target gear ratio).

When the non-shift determination is in progress, the process proceeds to step S117, a detection flag, which will be described in detail later, is reset to 0, and this routine is terminated.
On the other hand, if a shift determination is being made, the process proceeds to step S102, where the throttle opening TVO change amount ΔTVO per unit time, or the throttle opening at the time of switching from non-shifting to shifting (shift start time). The difference ΔTVO between the degree TVO and the current throttle opening TVO is calculated.

The throttle opening TVO is a state quantity that represents the load of the engine 1 as a power source, and the ΔTVO indicates a load change of the power source.
In step S103, a change amount ΔVSP per unit time of the vehicle speed VSP or a change amount ΔNT per unit time of the turbine rotation speed NT is calculated.
Specifically, the values ΔVSP and ΔNT are values obtained by subtracting the value before the unit time (for example, the value at the previous execution of this routine) from the latest value of the vehicle speed VSP or the turbine rotational speed NT.

Since the output shaft rotational speed Nout of the transmission is proportional to the vehicle speed VSP, the change amount ΔNout of the output shaft rotational speed Nout can be calculated instead of the vehicle speed VSP.
In step S104, the change amount ΔVSP or change amount ΔNT calculated before a predetermined time Δt (execution period of this routine × a positive integer n) is subtracted from the change amount ΔVSP or change amount ΔNT calculated in step S103. The result obtained is defined as ΔΔVSP or ΔΔNT.

In step S105, the time from the shift determination (shift control start) is measured.
In step S106, it is determined whether or not the time from shift determination (shift control start) is equal to or greater than a predetermined time TS (≧ 0).
When the time from the shift determination (shift control start) is less than the predetermined time TS, this routine is terminated without performing determination / control for torque reduction.

  The predetermined time TS may be set in consideration of a delay in shifting start of the transmission. Here, the predetermined time TS is set as a fixed value based on the matching result obtained by the actual machine or simulation, and the response of the release control of the friction engagement element is the shift type, engine load (load of the power source), automatic shift Corresponding to changes depending on the temperature of the hydraulic fluid of the machine, it can be variably set according to the gear type, engine load, and the temperature of the hydraulic oil of the automatic transmission, etc. Conceivable. The predetermined time TS is the same in the other embodiments.

The shift type is a distinction such as 1st speed → 2nd speed, 3rd speed → 4th speed, and the engine load can be represented by, for example, a throttle opening.
When the time from the shift determination (shift control start) is equal to or longer than the predetermined time TS, the process proceeds to step S107, and it is determined whether or not the absolute value of ΔTVO calculated in step S102 is smaller than the predetermined value α. .

  Here, when the absolute value of ΔTVO is greater than or equal to a predetermined value α (the load change of the power source is greater than or equal to a predetermined value), ΔΔVSP or ΔΔNT, which will be described later, is affected by a change in the transmission path of the transmission during the shift process. Therefore, the detection accuracy of the torque phase start based on ΔΔVSP or ΔΔNT is lowered, and the torque down request signal may be output at an incorrect timing.

The predetermined value α may be set as a fixed value based on a matching result obtained from an actual machine or a simulation, or may be set variably according to a shift type based on a difference in influence on ΔΔVSP or ΔΔNT. A configuration such as having it is conceivable.
When it is determined that the absolute value of ΔTVO is greater than or equal to the predetermined value α, the output control of the torque down request signal based on the detection timing of the torque phase start based on ΔΔVSP or ΔΔNT, which will be described later, is canceled (cancelling means) Then, the process proceeds to step S108, and the subsequent output control of the torque down request signal is performed based on the engine load.

However, the output control of the torque down request signal in step S108 is not limited to the above, and can be performed based on, for example, the indicated hydraulic pressure or actual hydraulic pressure of the friction engagement element, and the absolute value of ΔTVO is predetermined. When it is determined that the value is greater than or equal to the value α, the torque down control itself can be canceled so that the torque down is not performed.
In the output control of the torque down request signal based on the command hydraulic pressure or the actual hydraulic pressure, for example, when the time from the shift determination (shift control start) becomes equal to or longer than a predetermined time TS, the output of the torque down request signal is started. When the indicated hydraulic pressure or actual hydraulic pressure of the engagement side frictional engagement element reaches the reference level, the output of the torque down request signal is stopped.

On the other hand, if it is determined that the absolute value of ΔTVO is smaller than the predetermined value α, the process proceeds to step S109, and whether or not the torque down request signal output start process has been performed in the current shift (whether or not the output has started). ).
If the torque reduction request signal output start process is not performed in the current shift, the process proceeds to step S110 to start outputting the torque reduction request signal (torque down), and then terminate this routine.

Accordingly, the torque reduction is started when the time from the shift determination (shift control start) becomes equal to or longer than the predetermined time TS on condition that the absolute value of ΔTVO is smaller than the predetermined value α.
However, except that the absolute value of ΔTVO is smaller than the predetermined value α from the torque reduction start condition, it can be started when the time from the shift determination (shift control start) becomes equal to or greater than the predetermined time TS.

Further, since the predetermined time TS can be set to 0, the output of the torque down request signal can be started immediately when the shift is determined.
On the other hand, if it is determined in step S109 that the torque reduction request signal output start process has been performed in the current shift (including after the torque reduction is completed), the process proceeds to step S111 and subsequent steps to stop the output of the torque reduction request signal ( Torque down stop control).

First, in step S111, it is determined whether or not the absolute value of ΔΔVSP or ΔΔNT calculated in step S104 is smaller than a predetermined value β.
The predetermined value β is set according to, for example, a resistance component accompanying a change in the transmission path. In this case, the value of the predetermined value β may be variably set in accordance with the shift type, the acceleration state, etc. in addition to the fixed value based on the matching result obtained by the actual machine or the simulation. Conceivable.

If the absolute value of ΔΔVSP or ΔΔNT is greater than or equal to the predetermined value β, it is determined that the current time is the start time of the torque phase, the process proceeds to step S112, and the detection flag is set to 1. Further, in step S113, The time since the detection flag is set to 1 is measured.
Therefore, a state where 1 is set in the detection flag indicates that the start of the torque phase has been detected (after the start of the torque phase).

  The state where the absolute value of ΔΔVSP or ΔΔNT is equal to or greater than the predetermined value β is that the change amount ΔVSP or the change amount ΔNT calculated before a predetermined time Δt (execution period of the routine × a positive integer n) is in the torque phase. While the vehicle speed VSP before the torque is pulled or the value during the increase change of the turbine rotation speed NT, the latest change amount ΔVSP or the change amount ΔNT is the vehicle speed VSP or the turbine rotation speed after the start of the torque pull-in in the torque phase. This is a case where the value is a decreasing change in NT (see FIG. 6).

Here, if the predetermined time Δt is set to be small, it is easy to erroneously detect the start of the torque phase. On the other hand, if the predetermined time Δt is set to be large, the detection accuracy of the torque phase start is increased, but the detection delay may be increased. Therefore, the predetermined time Δt is adapted based on the detection accuracy and the detection response.
The detection of the start of the torque phase based on the vehicle speed VSP or the turbine rotational speed NT is not limited to the above method. For example, when the change amount ΔVSP or the change amount ΔNT changes from positive to negative (a time point when the maximum value is shown). Can be detected as the start of the torque phase.

Further, the start of the torque phase can be detected based on the change in the vehicle speed VSP and the change in the turbine rotational speed NT.
In step S114, it is determined whether or not 1 is set in the detection flag.
If 1 is set in the detection flag, the process proceeds to step S115, and the time from when 1 is set in the detection flag, that is, the elapsed time since the start of the torque phase is detected is a predetermined time γ. It is determined whether or not (≧ 0) is exceeded.

If the time since the detection flag is set to 1 exceeds the predetermined time γ, the process proceeds to step S116, the output of the torque down request signal to the engine control unit 21 is stopped, and the torque down control is stopped. (See FIG. 6).
The predetermined time γ is set as a fixed value based on a matching result obtained from an actual machine or a simulation, and the time from the start of the torque phase (torque pull-in) to the start of the change of the gear ratio depends on the speed change type, the engine load The predetermined time γ can be varied in accordance with the shift type, the engine load, and the temperature of the hydraulic oil in response to changes in the power source load, the temperature of the hydraulic oil in the automatic transmission, and the like. In this case, a configuration such as having a map is conceivable.

Specifically, as shown in FIG. 7, the predetermined time γ is lengthened as the temperature of the hydraulic oil ATF is lower, and as shown in FIG. 8, the throttle opening TVO is larger and the engine load is higher. The predetermined time γ is lengthened, and the predetermined time γ corresponding to the throttle opening TVO is increased or decreased by the speed change type at that time.
The above-mentioned speed change type indicates a distinction such as 1st speed → 2nd speed, 2nd speed → 3rd speed, etc., and a map is created based on the experimental determination of the difference in the required time γ depending on the speed change type. To do.

As described above, the predetermined time γ is changed according to the gear type, the engine load, and the temperature of the hydraulic oil in the automatic transmission, so that the torque down control is terminated at an optimal timing even if these conditions change. Can be made.
Note that one or two of the shift type, engine load, and temperature of the hydraulic fluid of the automatic transmission can be selected, and the predetermined time γ can be changed based on the selected condition, and the predetermined time TS can also be changed. It can be changed with the same characteristics as the predetermined time γ.

According to the above embodiment, when the time from the shift determination (shift control start) becomes equal to or greater than the predetermined time TS, torque reduction for temporarily reducing the output torque of the engine 1 (power source) is started, and the torque phase Torque-down is stopped when a predetermined time γ elapses after the start of is detected (see FIG. 6).
By the torque down control at the time of the upshift, as shown in FIG. 6, the torque immediately before the torque is pulled in the torque phase and the torque just after the pulling are lowered, thereby reducing the torque step and the torque changing speed in the pulling, The shift shock accompanying the pull-in is reduced.

  Further, since the end time of the torque reduction is determined based on the start time of the torque phase detected based on the vehicle speed VSP or the turbine rotational speed NT, the torque reduction continues excessively after the start of the torque phase. It can be avoided that the pulling is facilitated or that the shift shock due to the pulling of the torque cannot be sufficiently mitigated because the end of the torque reduction is too early with respect to the start of the torque phase.

The flowchart of FIG. 9 shows a first reference example of the output control of the torque down request signal for reducing the torque pulling shock in the torque phase by the A / T controller 11.
The routine shown in the flowchart of FIG. 9 is executed every predetermined minute time.
In step S201, it is determined whether a shift determination is being performed (upshift determination is being performed).

When shifting is being determined, a shift request (upshift request) is determined based on a determination that the target gear stage (target gear ratio) is different from the actual gear stage (gear ratio), and then the target gear stage This is the time until the actual gear stage (gear ratio) matches the (target gear ratio).
If the non-shift determination is being made, this routine is terminated as it is.
On the other hand, if a shift determination is being made, the process proceeds to step S202, where the throttle opening TVO change amount ΔTVO per unit time or the throttle opening at the time of switching from non-shifting to shifting (shift start time). The difference ΔTVO between the degree TVO and the current throttle opening TVO is calculated.

The throttle opening TVO is a state quantity that represents the load of the engine 1 as a power source, and the ΔTVO indicates a load change of the power source.
In step S203, a change amount ΔVSP per unit time of the vehicle speed VSP or a change amount ΔNT per unit time of the turbine rotation speed NT is calculated.
Specifically, the values ΔVSP and ΔNT are values obtained by subtracting the value before the unit time (for example, the value at the previous execution of this routine) from the latest value of the vehicle speed VSP or the turbine rotational speed NT.

Since the output shaft rotational speed Nout of the transmission is proportional to the vehicle speed VSP, the change amount ΔNout of the output shaft rotational speed Nout can be calculated instead of the vehicle speed VSP.
In step S204, the change amount ΔVSP or change amount ΔNT calculated before a predetermined time Δt (execution cycle of this routine × a positive integer n) is subtracted from the change amount ΔVSP or change amount ΔNT calculated in step S203 this time. The result obtained is defined as ΔΔVSP or ΔΔNT.

In step S205, the time from the shift determination (shift control start) is measured.
In step S206, it is determined whether or not the time from the shift determination (shift control start) is equal to or longer than a predetermined time TS (≧ 0).
When the time from the shift determination (shift control start) is less than the predetermined time TS, this routine is terminated without performing determination / control for torque reduction.

The predetermined time TS can be a fixed value, but the response of the frictional engagement element release control depends on the shift type, the engine load (load of the power source), the temperature of the hydraulic oil of the automatic transmission, and the like. Corresponding to the change, the predetermined time TS can be variably set according to the shift type, the engine load, and the temperature of the hydraulic oil of the automatic transmission.
If the time from the shift determination (shift control start) is equal to or greater than the predetermined time TS, the process proceeds to step S207, and whether or not the torque down request signal output start process has been performed in the current shift (after the output start) Or not).

If the torque down request signal output start process is not performed in the current shift, the process proceeds to step S208 to start outputting the torque down request signal (torque down), and then terminate this routine.
The engine control unit 21 that has received the torque down request signal executes torque down control for temporarily reducing the output torque of the engine 1.

Accordingly, the torque reduction is started when the time from the shift determination (shift control start) reaches the predetermined time TS (≧ 0).
On the other hand, if it is determined in step S207 that the torque down request signal output start process has been performed in the current shift (including after the torque reduction ends), the process proceeds to step S209.
In step S209, a time TE (> TS) corresponding to the speed change condition at that time is stored from a map in which the time TE from the shift determination (start of speed change control) to the stop of torque reduction is stored rewritable for each speed change condition. read out.

  The time TE is a time set to end the torque reduction at a time point before the target time TG (> 0) before the start time of the torque phase (see FIG. 10), and the initial value has various variations. The torque pull-down control is set so as not to increase the torque pull-in even if there is, and as described later, the initial value is measured by measuring the time from the shift determination (shift control start) to the torque phase start. The learning is updated from.

Further, the shift conditions include a shift type, an engine load (load of a power source), a temperature of hydraulic oil of the automatic transmission, and the time TE can be updated according to at least one of them. Remember.
In order to learn the time TE described later, the target time TG is also stored in advance according to the same shift conditions as the map for storing the time TE.

In step S210, it is determined whether or not an elapsed time has reached the time TE from the shift determination (shift control start).
If the elapsed time from the shift determination (shift control start) has reached the time TE, the process proceeds to step S211, and the output of the torque down request signal (torque down) is stopped (see FIG. 10).

Therefore, in the control shown in the flowchart of FIG. 9 , torque reduction is started when the elapsed time from the shift determination (shift control start) reaches the predetermined time TS, and the elapsed time from the shift determination (shift control start) is the time. At the time when TE (> TS) is reached and the target time TG is earlier than the start time of the torque phase, the torque reduction ends (see FIG. 10).
In the torque down control at the time of the upshift, as shown in FIG. 10, the torque immediately before the torque is drawn in the torque phase by setting the end time of the torque down by the target time TG before the start time of the torque phase. Thus, the torque step in the pull-in is reduced, and the shift shock accompanying the pull-in is reduced.

In step S212, it is determined whether or not the absolute value of ΔTVO calculated in step S202 is smaller than a predetermined value α.
Here, when the absolute value of ΔTVO is greater than or equal to the predetermined value α (the load change of the power source is greater than or equal to the predetermined value), the detection accuracy of the torque phase start based on ΔΔVSP or ΔΔNT is lowered, and torque down ends as described later The learning accuracy at the time (time TE) is lowered.

Therefore, when it is determined that the absolute value of ΔTVO is equal to or larger than the predetermined value α, learning of the torque down end time (time TE) based on detection of the torque phase start based on ΔΔVSP or ΔΔNT, which will be described later, is canceled ( Canceling means), this routine is terminated as it is.
On the other hand, if the absolute value of ΔTVO is less than the predetermined value α, it is determined that the start of the torque phase can be accurately detected based on ΔΔVSP or ΔΔNT, and the process proceeds to step S213.

In step S213, it is determined whether or not the absolute value of ΔΔVSP or ΔΔNT calculated in step S204 is smaller than a predetermined value β.
If the absolute value of ΔΔVSP or ΔΔNT is greater than or equal to the predetermined value β, it is determined that the current time is the start time of the torque phase.
The state where the absolute value of ΔΔVSP or ΔΔNT is equal to or greater than the predetermined value β is that the change amount ΔVSP or the change amount ΔNT calculated before a predetermined time Δt (execution period of the routine × a positive integer n) is in the torque phase. While the vehicle speed VSP before the torque is pulled or the value during the increase change of the turbine rotation speed NT, the latest change amount ΔVSP or the change amount ΔNT is the vehicle speed VSP or the turbine rotation speed after the start of the torque pull-in in the torque phase. This is a case where the value is a decreasing change in NT (see FIG. 10).

Here, if the predetermined time Δt is set to be small, it is easy to erroneously detect the start of the torque phase. On the other hand, if the predetermined time Δt is set to be large, the detection accuracy of the torque phase start is increased, but the detection delay may be increased. Therefore, the predetermined time Δt is adapted based on the detection accuracy and the detection response.
The detection of the start of the torque phase based on the vehicle speed VSP or the turbine rotational speed NT is not limited to the above method. For example, when the change amount ΔVSP or the change amount ΔNT changes from positive to negative (a time point when the maximum value is shown). Can be detected as the start of the torque phase.

Further, the start of the torque phase can be detected based on the change in the vehicle speed VSP and the change in the turbine rotational speed NT.
In the method of detecting the start of the torque phase based on a predetermined change in the engine load, the start of the torque phase can be accurately detected because it is greatly influenced by the change in the engine load accompanying the accelerator operation by the driver during the shift. Although difficult, in the detection of the torque phase start based on the vehicle speed VSP or the turbine rotational speed NT, more stable and accurate detection is possible.

When the start time of the torque phase is detected, the process proceeds to step S214, and learning update of the time TE is performed.
Specifically, from the measurement time TT from the shift determination (shift control start) to the detection of the torque phase start, the shift conditions (shift type, engine load power source load, automatic transmission hydraulic oil temperature at that time) The result (TE = TT−TG) obtained by subtracting the target time TG stored in advance according to the time is updated and stored as the time TE corresponding to the speed change condition at that time.

When updating the time TE, the weighted average value can be stored by performing a weighted average calculation using the previous stored value and the newly calculated time TE.
Further, when the absolute value of the difference between the stored value so far and the newly calculated time TE is equal to or greater than a predetermined value, the update can be prohibited. Thereby, it is possible to avoid updating the time TE based on the abnormal value.

  As described above, if the time TT from the shift determination (shift control start) to the detection of the torque phase start is measured and the time TE is updated and learned based on the measurement result, the automatic transmission 3 Even if the time TT from the shift determination (shift control start) to the start of the torque phase varies due to variations and deterioration over time, the torque reduction can be reliably ended at a time point before the target time TG from the start of the torque phase. it can.

Further, the control shown in the flowchart of FIG. 9 is performed based on the time measurement from the shift determination based on the learning result, and is not performed by detecting the start of the torque phase. Even if the fluctuation of the torque phase is large and it is difficult to detect the start of the torque phase, the torque down end control can be performed based on the start of the torque phase.

The flowchart of FIG. 11 shows a second reference example of the output control of the torque down request signal for reducing the torque pulling shock in the torque phase by the A / T controller 11.
The routine shown in the flowchart of FIG. 11 is executed every predetermined minute time.
In step S301, it is determined whether a shift determination is being performed (upshift determination is being performed).

When shifting is being determined, a shift request (upshift request) is determined based on a determination that the target gear stage (target gear ratio) is different from the actual gear stage (gear ratio), and then the target gear stage This is the time until the actual gear stage (gear ratio) matches the (target gear ratio).
If the non-shift determination is being made, this routine is terminated as it is.
On the other hand, if a shift determination is being made, the process proceeds to step S302, where the throttle opening TVO change amount ΔTVO per unit time or the throttle opening at the time of switching from a non-shift to a shift (shift start time). The difference ΔTVO between the degree TVO and the current throttle opening TVO is calculated.

The throttle opening TVO is a state quantity that represents the load of the engine 1 as a power source, and the ΔTVO indicates a load change of the power source.
In step S303, a change amount ΔVSP per unit time of the vehicle speed VSP or a change amount ΔNT per unit time of the turbine rotation speed NT is calculated.
Specifically, the values ΔVSP and ΔNT are values obtained by subtracting the value before the unit time (for example, the value at the previous execution of this routine) from the latest value of the vehicle speed VSP or the turbine rotational speed NT.

Since the output shaft rotational speed Nout of the transmission is proportional to the vehicle speed VSP, the change amount ΔNout of the output shaft rotational speed Nout can be calculated instead of the vehicle speed VSP.
In step S304, the change amount ΔVSP or change amount ΔNT calculated before a predetermined time Δt (execution period of this routine × a positive integer n) is subtracted from the change amount ΔVSP or change amount ΔNT calculated in step S303 this time. The result obtained is defined as ΔΔVSP or ΔΔNT.

In step S305, the time from the shift determination (shift control start) is measured.
In step S306, a time TK (> 0) corresponding to the speed change condition at that time is stored from a map in which the time TK from the shift determination (start of speed change control) to the start of torque reduction is stored rewritable for each speed change condition. read out.
The time TK is a time set to start the torque reduction at a time point before the target time TG2 (> 0) before the start time of the torque phase (see FIG. 12), and the initial value has various variations. The torque pull-down control is set so as not to increase the torque pull-in even if there is, and as described later, the initial value is measured by measuring the time from the shift determination (shift control start) to the torque phase start. The learning is updated from.

Further, the shift conditions include a shift type, an engine load (load of a power source), a temperature of hydraulic oil of the automatic transmission, and the time TK can be updated according to at least one of them. Remember.
For the purpose of learning the time TK, which will be described later, the target time TG2 is also stored in advance according to the same shift conditions as the map for storing the time TK.

In step S307, it is determined whether or not an elapsed time has reached the time TK from the shift determination (shift control start).
Then, when the elapsed time from the shift determination (shift control start) reaches the time TK, the process proceeds to step S308 to start outputting a torque down request signal (torque down) (see FIG. 12).

The engine control unit 21 that has received the torque down request signal executes torque down control for temporarily reducing the output torque of the engine 1.
In step S309, it is determined whether an inertia phase has been started.
The start of the inertia phase is determined based on whether or not the gear ratio calculated from the input shaft rotation speed (turbine rotation speed) and the output shaft rotation speed of the automatic transmission 3 has started to change.

If the start of the inertia phase is determined, the process proceeds to step S310, and the output of the torque down request signal (torque down) is stopped (see FIG. 12).
Therefore, in the control shown in the flowchart of FIG. 11 , the torque is measured at the time when the elapsed time from the shift determination (shift control start) reaches the time TK and the target time TG2 before the start time of the torque phase. The down is started, and the torque down is stopped when the inertia phase is started.

As described above, by starting the torque reduction from the time point before the target time TG2 before the start time of the torque phase and ending the torque reduction with the start of the inertia phase, as shown in FIG. The torque pull-in can be moderated, thereby reducing a shift shock accompanying the pull-in.
In step S311, it is determined whether or not the absolute value of ΔTVO calculated in step S302 is smaller than a predetermined value α.

Here, when the absolute value of ΔTVO is equal to or larger than the predetermined value α, the detection accuracy of the torque phase start based on ΔΔVSP or ΔΔNT is lowered, and error factors such as time delay are expanded, and the torque down start timing described later The learning accuracy of (time TK) is lowered.
Therefore, if it is determined that the absolute value of ΔTVO is greater than or equal to the predetermined value α (the load change of the power source is greater than or equal to the predetermined value), torque reduction based on detection of a torque phase start based on ΔΔVSP or ΔΔNT, which will be described later, is performed. The learning of the start time (time TK) is canceled (cancellation means), and this routine is terminated as it is. Thereby, it is possible to avoid updating the torque reduction start time (time TK) based on the abnormal value.

On the other hand, if the absolute value of ΔTVO is less than the predetermined value α, it is determined that the torque phase start can be accurately detected based on ΔΔVSP or ΔΔNT, and the process proceeds to step S312.
In step S312, it is determined whether or not the absolute value of ΔΔVSP or ΔΔNT calculated in step S304 is smaller than a predetermined value β.
If the absolute value of ΔΔVSP or ΔΔNT is greater than or equal to the predetermined value β, it is determined that the current time is the start time of the torque phase.

  The state where the absolute value of ΔΔVSP or ΔΔNT is equal to or greater than the predetermined value β is that the change amount ΔVSP or the change amount ΔNT calculated before a predetermined time Δt (execution period of the routine × a positive integer n) is in the torque phase. While the vehicle speed VSP before the torque is pulled or the value during the increase change of the turbine rotation speed NT, the latest change amount ΔVSP or the change amount ΔNT is the vehicle speed VSP or the turbine rotation speed after the start of the torque pull-in in the torque phase. This is a case where the value is a decreasing change in NT (see FIG. 12).

Here, if the predetermined time Δt is set to be small, it is easy to erroneously detect the start of the torque phase. On the other hand, if the predetermined time Δt is set to be large, the detection accuracy of the torque phase start is increased, but the detection delay may be increased. Therefore, the predetermined time Δt is adapted based on the detection accuracy and the detection response.
The detection of the start of the torque phase based on the vehicle speed VSP or the turbine rotational speed NT is not limited to the above method. For example, when the change amount ΔVSP or the change amount ΔNT changes from positive to negative (a time point when the maximum value is shown). Can be detected as the start of the torque phase.

Further, the start of the torque phase can be detected based on the change in the vehicle speed VSP and the change in the turbine rotational speed NT.
When the start time of the torque phase is detected, the process proceeds to step S313, and learning update of the time TK is performed.
Specifically, from the time TT from the shift determination (shift control start) to the detection of the torque phase start, the shift condition at that time (shift type, engine load power source load, temperature of hydraulic oil for automatic transmission, etc.) ), The result of subtracting the target time TG stored in advance (TK = TT−TG) is updated and stored as the time TK corresponding to the speed change condition at that time.

When the time TK is updated, the weighted average value can be stored by performing a weighted average calculation using the previous stored value and the newly calculated time TK.
In addition, the update can be prohibited when the absolute value of the difference between the stored value so far and the newly calculated time TK is equal to or greater than a predetermined value.
As described above, if the time TT from the shift determination (shift control start) to the detection of the start of the torque phase is measured and the time TK is updated and learned based on the measurement result, the automatic transmission 3 Even if the time TT from the shift determination (shift control start) to the start of the torque phase varies due to variations and deterioration over time, the torque reduction can be surely started at a time point before the target time TG from the start of the torque phase. it can.

Further, the control shown in the flowchart of FIG. 11 is performed based on the time measurement from the shift determination based on the learning result, and is not performed by detecting the start of the torque phase. Even in a situation where the fluctuation of the torque is large and it is difficult to detect the start of the torque phase, the torque down start control can be performed based on the start of the torque phase.

It should be noted that the torque reduction that is started by the target time TG2 before the start time of the torque phase can be stopped when a predetermined time γ elapses after the start of the torque phase is detected.
Further, the torque reduction started before the target time TG2 from the start time of the torque phase can be ended at a time point before the target time TG (<TG2) from the start time of the torque phase.

  Further, based on the speed change conditions such as the shift type, the load of the engine 1 (load of the power source), the temperature of the hydraulic oil, etc., the end time of the torque reduction is set to be after a predetermined time γ has elapsed from the start of the torque phase, or the inertia Select whether to synchronize with the start of the phase or just before the target time TG from the start of the torque phase, and to set the start time of torque reduction according to the selection of the end time, after a predetermined time TS has elapsed from the shift determination Or the time point before the target time TG2 from the start of the torque phase can be selected.

Furthermore, the predetermined time γ and the target times TG and TG2 can be updated and learned based on the result of detecting the magnitude of the speed change shock (the magnitude and speed of the torque pull-in) .

The system diagram which shows the vehicle drive system containing the automatic transmission in embodiment. The skeleton figure which shows the speed change mechanism in embodiment. The figure which shows the combination of each gear stage and the fastening state of a friction engagement element in the transmission mechanism in embodiment. The figure which shows the combination of each gear position in the transmission mechanism in embodiment, and ON / OFF of a shift solenoid. The flowchart which shows embodiment of the output control of a torque down request signal. The time chart which shows the characteristic of the torque down control in the torque phase in embodiment . The diagram which shows the correlation with hydraulic oil temperature and time (gamma) from the start of a torque phase until it complete | finishes torque reduction in embodiment. The diagram which shows the correlation with time (gamma) from the start of a throttle opening (engine load), a gearshift type, and a torque phase to completion | finish of torque reduction in embodiment. The flowchart which shows the 1st reference example of output control of a torque down request signal. The time chart which shows the characteristic of the torque down control in the torque phase in a 1st reference example . The flowchart which shows the 2nd reference example of output control of a torque down request signal. The time chart which shows the characteristic of the torque down control in the torque phase in a 2nd reference example .

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Torque converter, 3 ... Automatic transmission, 5 ... Shift solenoid (A), 6 ... Shift solenoid (B), 7 ... Line pressure solenoid, 11 ... AT controller, 12 ... ATF temperature sensor, 13 ... Accelerator opening sensor, 14 ... Vehicle speed sensor, 15 ... Engine rotation sensor, 16 ... Inhibitor switch, 17 ... Turbine sensor, 21 ... Engine control unit, 31 ... Electronically controlled throttle device, 32 ... Fuel injection valve, 33 ... Ignition device

Claims (4)

In a vehicular automatic transmission combined with a power source, a control device for a vehicular automatic transmission that performs torque down to reduce output torque of the power source in order to reduce a torque pulling shock in a torque phase at the time of shifting. There,
Control time setting means for setting the time when a predetermined time has elapsed from the start time of the torque phase as the end time of torque reduction, and increasing the predetermined time as the temperature of the hydraulic oil of the automatic transmission decreases. A control device for an automatic transmission for a vehicle, characterized in that it is configured. In a vehicular automatic transmission combined with a power source, a control device for a vehicular automatic transmission that performs torque down to reduce output torque of the power source in order to reduce a torque pulling shock in a torque phase at the time of shifting. There,
It is configured to include a control time setting means for setting a time point after a predetermined time from the start time of the torque phase as an end time of the torque reduction, and increasing the predetermined time as the load of the power source is higher. control system for an automatic transmission for a vehicle according to claim. Provided is a canceling means for canceling the setting of the torque down end time based on the elapsed time from the start time of the torque phase by the control time setting means when the change in the load of the power source during the shift is not less than a predetermined value. The control device for an automatic transmission for a vehicle according to claim 1 or 2 . The control timing setting means detects the start timing of the torque phase based on at least one of a change in vehicle speed and a change in input shaft rotation speed of the transmission. The control apparatus of the automatic transmission for vehicles as described in any one of .

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