JP5125878B2 - Shift control device for automatic transmission when vehicle speed limit is released - Google Patents

Description

  The present invention relates to a shift control technique of an automatic transmission when a vehicle with a vehicle speed limit control device is switched from a vehicle speed limit state to a vehicle speed limit release state when the vehicle speed limit is released.

The vehicle speed limit control device controls the driving force so that the actual vehicle speed does not exceed the arbitrarily set limit vehicle speed even when the driver depresses the accelerator pedal greatly.
This is very useful in that the driver can carry out observing the legal vehicle speed while keeping the vehicle speed below the limit vehicle speed without worrying about the accelerator pedal operation.

As such a vehicle speed limit control device, a device described in Patent Document 1, for example, is conventionally known.
This vehicle speed limit control device limits the maximum value of the required engine operation load such as the accelerator opening and the throttle opening according to the vehicle speed deviation between the limited vehicle speed and the actual vehicle speed, and switches the limited vehicle speed during vehicle speed limit control. To alleviate the shock.
JP 11-294215 A

  However, although the conventional vehicle speed limit control devices represented by the above are provided with measures to alleviate the shock during the vehicle speed limit control, the measures against the shock when the vehicle speed limit is released from the vehicle speed limit control state are provided. It was not given.

The shock when the vehicle speed limit is canceled will be described below.
While the vehicle speed is limited, the engine operation demand load (throttle opening etc.) is reduced to limit the wheel driving force (engine output) so that the actual vehicle speed does not exceed the limited vehicle speed even if the accelerator pedal is depressed greatly. Has been.

On the other hand, the automatic transmission that directs the engine output to the drive wheel is controlled to shift using the engine operation request load (throttle opening, etc.) as one of the control factors.
Accordingly, during the vehicle speed limitation, the automatic transmission is controlled to be shifted based on the engine operation request load for limiting the vehicle speed which is reduced to limit the vehicle speed.

When the vehicle speed restriction is released, the engine operation request load is switched from a small value for vehicle speed restriction to a large driver request load that the driver desires depending on the amount of depression of the accelerator pedal.
Therefore, the shift of the automatic transmission is controlled based on a large engine operation request load corresponding to the driver's accelerator pedal depression amount from the time when the vehicle speed restriction is released.

For this reason, if the vehicle speed limit is released while the driver depresses the accelerator pedal greatly, the engine operation request load used for the shift control of the automatic transmission will correspond to the accelerator pedal depression amount from the small vehicle speed limit request load. Switches to a large driver demand load.
The load increase from such a small vehicle speed limiting demand load to a large driver demand load causes a downshift of the automatic transmission, and if the step difference between the vehicle speed limiting demand load and the driver demand load is large, the gear ratio changes. This causes a problem that the shift shock is increased due to the large width.
In particular, when the automatic transmission is a stepped automatic transmission, a jump downshift occurs when the vehicle speed limit is released, and the problem of the shift shock becomes more remarkable.

In view of the above circumstances, the present invention proposes a speed change control device that can reduce a speed change shock so that it does not become a problem in spite of a large speed ratio change width at the time of canceling the vehicle speed limit,
Accordingly, it is an object of the present invention to provide an improvement technique for a vehicle speed limit release shock caused by the shift shock.

For this purpose, the shift control device for an automatic transmission at the time of releasing the vehicle speed restriction according to the present invention is configured as follows .
First of all, the vehicle speed limit control device as a premise will be described.
A vehicle speed detecting means for detecting an actual vehicle speed of a vehicle having a power train composed of a prime mover and an automatic transmission that transmits power from the prime mover to drive wheels;
Limit vehicle speed setting means for setting a limit vehicle speed as a vehicle speed upper limit value;
Driving force limiting means for limiting the wheel driving force so that the actual vehicle speed does not exceed the limited vehicle speed in response to signals from these means;
Vehicle speed restriction releasing means for releasing the vehicle speed restriction by the driving force limiting means when the predetermined condition is satisfied.

The shift control device of the automatic transmission at the time of releasing the vehicle speed limit of the first invention is such a vehicle speed limit control device as a premise ,
The shift of the automatic transmission accompanying the release of the vehicle speed limit is basically performed under a predetermined shift speed limit, but at the beginning of the shift from the speed ratio immediately before the release of the vehicle speed limit to the speed ratio after the release of the vehicle speed limit, Shift speed limiting means for limiting the shift speed with respect to the shift from the predetermined speed ratio to the speed ratio after the vehicle speed limit is released without limiting the speed to a predetermined speed ratio at which sudden gear change is allowed. It is characterized by the provided structure.
Further, the shift control device of the automatic transmission at the time of releasing the vehicle speed limit of the second invention is based on the vehicle speed limit control device as a premise,
The shift of the automatic transmission associated with the release of the vehicle speed limit is performed under a predetermined shift speed limit. When the shift speed is limited, a shift control factor of the automatic transmission that switches according to the release of the vehicle speed limit is set. The shift speed is limited by gradually changing from the value immediately before the switching to the value after the switching to contribute to the shift control, and the shift control factor is changed from the value immediately before the switching to the value after the switching. And a speed change speed limiting means for further reducing the speed to be changed during the shift of the automatic transmission.
Furthermore, the shift control device of the automatic transmission at the time of releasing the vehicle speed limit of the third invention is based on the vehicle speed limit control device as a prerequisite.
The shift of the automatic transmission accompanying the release of the vehicle speed limit is performed under a predetermined shift speed limit. When the shift speed is limited, the higher the vehicle speed at the release of the vehicle speed limit, the higher the vehicle speed limit. The present invention is characterized in that a shift speed limiting means for reducing the shift speed limit degree with respect to the shift associated with the release of is provided.

According to the shift control device of the automatic transmission at the time of canceling the vehicle speed restriction of the first to third inventions,
In order for the shift speed limiting means to perform the shift of the automatic transmission accompanying the change of the prime mover operation request load due to the release of the vehicle speed limit under the predetermined shift speed limit,
Even when the speed ratio change range at the time of releasing the vehicle speed restriction is large, the speed change shock is reduced, and the vehicle speed restriction release shock caused by this speed change shock can be reduced.
In addition, according to the first aspect of the present invention, the shift speed is not limited to a predetermined gear ratio at which an abrupt shift is allowed at the beginning of the shift from the gear ratio immediately before the release of the vehicle speed restriction to the gear ratio after the vehicle speed restriction is released, In order to limit the shift speed with respect to the shift from the predetermined speed ratio to the speed ratio after the vehicle speed restriction is released,
Despite the fact that the sudden speed change is a speed change up to a predetermined speed ratio, the above-mentioned speed limit restriction can be avoided, and the total speed change time to the speed ratio after the vehicle speed restriction is released is shortened. can do.
In the second aspect of the invention, when the shift speed is limited, a shift control factor that is switched when the vehicle speed limit is released is gradually changed from a value immediately before the switching to a value after the switching to limit the shifting speed. To further reduce the speed of change of the shift control factor during shifting of the automatic transmission,
The shift control factor reaches a value that crosses the next shift line before the shift in progress is completed, and the jumping shift is not performed, so that the occurrence of a shock can be prevented.
Further, in the third aspect of the invention, when the shift speed is limited, the higher the vehicle speed at the time of releasing the vehicle speed limit, the smaller the degree of the shift speed limit with respect to the shift associated with the release of the vehicle speed limit. An effect is obtained.
In other words, at high vehicle speeds, the effects of shift shocks are smaller than at low vehicle speeds, and the problems caused by this can be solved relatively easily, and quick acceleration is required when the vehicle speed limit is released.
The higher the vehicle speed as in the third aspect of the invention, the weaker the speed limit at the time of releasing the vehicle speed limit agrees well with the actual situation, and can prevent the speed change from being reduced more than necessary at the time of high vehicle speed. It is possible to satisfy a quick acceleration request when the vehicle speed limit is released.

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
FIG. 1 is a functional block diagram related to a vehicle speed limit control device 1 for a vehicle including a speed change control device according to an embodiment of the present invention.
2 represents an engine as a prime mover, and 3 represents an automatic transmission.
A vehicle having a power train composed of the engine 2 and the automatic transmission 3 can travel while the power from the engine 2 is transmitted to driving wheels (not shown) while being shifted by the automatic transmission 3.

  The vehicle speed limiting control device 1 includes a vehicle speed limiting operation determining unit 11, a vehicle speed limiting target driving force calculating unit 12, a vehicle speed limiting target throttle opening calculating unit 13, a meter display signal generating unit 14, and a driver request driving A force calculation unit 15, a driver-requested throttle opening calculation unit 16, a kickdown determination unit 17, and a throttle opening command selection unit 18 are included.

The vehicle speed limit control device 1 includes a signal from a vehicle speed sensor 21 (vehicle speed detection means) that detects the actual vehicle speed VSP,
A signal from a vehicle speed limit control switch group 22a provided on the steering wheel 22,
A signal from an accelerator opening sensor 23a for detecting the depression amount (accelerator opening) APO of the accelerator pedal 23;
A signal from the engine rotation sensor 24 for detecting the engine speed Ne is input.

The vehicle speed limit control switch group 22a includes a "SET" switch, a "RES" switch, and a "CANCEL" switch.
In response to the “SET” signal, “RES” signal, and “CANCEL” signal from these switches, the vehicle speed limit operation determination unit 11 sets the limit vehicle speed LmtVSP as described below, The vehicle speed limit shall be lifted.

After the engine 2 ignition switch (not shown) is turned on and the vehicle speed limit has not been performed yet, and the driver desires vehicle speed limit control, the “SET” switch or “RES” Press the switch.
At this time, in response to the “SET” signal or the “RES” signal from the “SET” switch or the “RES” switch, the vehicle speed limit operation determining unit 11 sets the actual vehicle speed VSP at the time of the switch operation as the limited vehicle speed LmtVSP. ,
At the same time, a vehicle speed limit operation signal Sop is output to indicate that the vehicle speed limit control should be performed.

Thereafter, every time the driver presses the “SET” switch, the vehicle speed limit operation determination unit 11 responds to the “SET” signal from the switch to increase the limit vehicle speed LmtVSP at the “1 Km / h” pitch,
Each time the driver presses the “RES” switch, the vehicle speed limit operation determination unit 11 decreases the limit vehicle speed LmtVSP at a “1 Km / h” pitch in response to the “RES” signal from the switch.

At this time, if the driver keeps pressing the “SET” switch for more than the set time, the vehicle speed limit operation determination unit 11 responds to the “SET” signal duration from the switch and increases the pitch of the limit vehicle speed LmtVSP. From the original "1Km / h" to "10Km / h", and the vehicle speed limit LmtVSP increases rapidly.
When the driver keeps pressing the “RES” switch for a set time or longer, the vehicle speed limit operation determining unit 11 responds to the “RES” signal duration from the switch and sets the decrease pitch of the limit vehicle speed LmtVSP to the initial value. Switch from "1Km / h" to "10Km / h" and suddenly reduce the vehicle speed limit LmtVSP.
Therefore, the vehicle speed limit operation determination unit 11 corresponds to the limit vehicle speed setting means in the present invention.

The driver presses the “CANCEL” switch when he wants to end the vehicle speed limit control.
At this time, the vehicle speed limit operation determination unit 11 causes the vehicle speed limit operation signal Sop to disappear in response to the “CANCEL” signal from the switch.
Therefore, the limit vehicle speed LmtVSP is kept at the value at the time of disappearance of the vehicle speed limit operation signal Sop until the engine ignition switch is turned OFF for the next vehicle speed limit control.
Next, when the driver desires vehicle speed limit control and presses the “SET” switch or “RES” switch, the stored limit vehicle speed LmtVSP is used as an initial value.

Based on the accelerator opening APO, the kickdown determination unit 17 determines whether or not the accelerator pedal 23 is in a kickdown state in which the pedal is depressed to the maximum vicinity, and outputs a kickdown signal Skd when in the kickdown state. When not in the kick down state, the kick down signal Skd is not output.
As described above, the vehicle speed limit operation determining unit 11 eliminates the vehicle speed limit operation signal Sop in response to the “CANCEL” signal, and also when the vehicle is in the kickdown state in response to the kickdown signal Skd, Let Sop disappear.

In addition, the vehicle speed limit operation determination unit 11 also eliminates the vehicle speed limit operation signal Sop even when the vehicle speed VSP is a low vehicle speed lower than the set vehicle speed that should not be limited.
Accordingly, the vehicle speed limit operation determination unit 11 also constitutes a vehicle speed limit release means in the present invention.
Even when the vehicle speed limit operation signal Sop disappears in response to these kick-down states or low vehicle speeds, the vehicle speed limit operation signal Sop remains until the engine ignition switch is turned OFF for the next vehicle speed limit control. Keep the value at the time of disappearance of
Next, when the driver desires vehicle speed limit control and presses the “SET” switch or “RES” switch, the stored limit vehicle speed LmtVSP is used as an initial value.

The vehicle speed limiting target driving force calculation unit 12 receives the vehicle speed limiting operation signal Sop, the limiting vehicle speed LmtVSP, and the actual vehicle speed VSP, and between the limited vehicle speed LmtVSP and the actual vehicle speed VSP while the vehicle speed limiting operation signal Sop exists. The vehicle speed limit target driving force LmtTd is calculated so that the actual vehicle speed VSP does not exceed the limit vehicle speed LmtVSP as the vehicle speed deviation decreases.
Therefore, the vehicle speed limiting target driving force calculator 12 corresponds to the driving force limiting means in the present invention.
Thus, while the vehicle speed limiting operation signal Sop is not present, the vehicle speed limiting target driving force calculation unit 12 fixes the vehicle speed limiting target driving force LmtTd to a maximum realizable value.

The vehicle speed limiting target throttle opening calculating unit 13 is a vehicle speed for realizing the vehicle speed limiting target driving force LmtTd based on the vehicle speed limiting target driving force LmtTd and the vehicle speed limiting operation signal Sop obtained as described above. Obtain the target throttle opening LmtTVO for restriction.
Needless to say, when the vehicle speed limiting target driving force LmtTd is fixed to a maximum value that can be achieved, the vehicle speed limiting target throttle opening LmtTVO is a throttle opening fully open value.

When the vehicle speed limit operation signal Sop is present based on the limit vehicle speed LmtVSP and the vehicle speed limit operation signal Sop, the meter display signal generation unit 14 is as shown in the limit vehicle speed display unit 31a of the meter panel 31 in front of the driver seat. Generate a meter display signal to display the limit vehicle speed LmtVSP,
When the vehicle speed limit operation signal Sop does not exist, a meter display signal is generated so that the vehicle speed limit non-operation is displayed on the limit vehicle speed display unit 31a of the meter panel 31 instead of the limit vehicle speed LmtVSP.

The driver requested driving force calculation unit 15 is requested by the driver by operating the accelerator pedal based on the current engine speed Ne based on the planned driving force map from the accelerator opening APO and the engine speed Ne. The required driver driving force DrvTd is calculated.
The driver-requested throttle opening calculator 16 obtains the driver-requested throttle opening DrvTVO for realizing the driver-requested driving force DrvTd.
The throttle opening command selection unit 18 is the smaller of the driver required throttle opening DrvTVO and the vehicle speed limiting target throttle opening LmtTVO obtained by the calculation unit 13 as described above, Min (DrvTVO, LmtTVO) Is selected as the throttle opening command tTVO.

The engine 2 includes an electronically controlled throttle valve 32, and the output is adjusted by electronically controlling the opening degree of the throttle valve 32 by a motor 33.
The throttle opening command tTVO = Min (DrvTVO, LmtTVO) selected as described above by the throttle opening command selection unit 18 is commanded to the motor 33, and the throttle valve 32 is opened via the motor 33 so that the opening of the throttle Electronic control is performed so as to coincide with the degree command tTVO = Min (DrvTVO, LmtTVO).

The vehicle speed limit control based on the output control of the engine 2 through the opening control of the electronically controlled throttle valve 32 will be described in detail below.
During the vehicle speed limiting control in which the vehicle speed limiting operation signal Sop is output, the vehicle speed limiting target driving force LmtTd obtained by the vehicle speed limiting target driving force calculation unit 12 becomes VSP (actual vehicle speed)> LmtVSP (restricted vehicle speed). It is a value that prevents it from happening.

Therefore, when the driver depresses the accelerator pedal 23 greatly and the driver required driving force DrvTd is larger than the vehicle speed limiting target driving force LmtTd, the driver required throttle opening DrvTVO is larger than the vehicle speed limiting target throttle opening LmtTVO. Since it is larger, the selector 18 selects the smaller one of them, that is, the vehicle speed limiting target throttle opening LmtTVO as the throttle opening command tTVO, and contributes to the opening control of the electronically controlled throttle valve 32.
Therefore, even if the driver depresses the accelerator pedal 23 greatly, the output of the engine 2 is limited so that the actual vehicle speed VSP does not exceed the limit vehicle speed LmtVSP, and the vehicle speed limit control can be performed.

Even during the vehicle speed limiting control in which the vehicle speed limiting operation signal Sop is output, the amount of depression of the accelerator pedal 23 (accelerator opening APO) by the driver is small, and the driver required driving force DrvTd is the target driving force for limiting the vehicle speed. If less than LmtTd,
Since the driver required throttle opening DrvTVO is smaller than the target throttle opening LmtTVO for vehicle speed limitation, the selection unit 18 selects the smaller one of them, that is, the driver required throttle opening DrvTVO as the throttle opening command tTVO. It contributes to the opening degree control of the electronically controlled throttle valve 32.
Therefore, since the driver does not greatly depress the accelerator pedal 23, during the operation where the actual vehicle speed VSP does not exceed the limit vehicle speed LmtVSP, the output of the engine 2 can be controlled so as to realize the driver required driving force DrvTd, It is possible to avoid troubles in normal driving.

The driver presses the `` CANCEL '' switch in the switch group 22a, the driver enters a kick-down state where the accelerator pedal 23 is depressed to the maximum vicinity, the vehicle speed VSP becomes extremely low, and the vehicle speed limit operation signal Sop is While vehicle speed limit control is not being executed after it no longer exists,
The vehicle speed limiting target driving force calculation unit 12 fixes the vehicle speed limiting target driving force LmtTd to the maximum feasible value.
Therefore, no matter how much the driver depresses the accelerator pedal 23, the driver required driving force DrvTd does not become larger than the vehicle speed limiting target driving force LmtTd, and the driver required throttle opening DrvTVO does not exceed the vehicle speed limiting target throttle. No greater than LmtTVO degree.

Therefore, the selection unit 18 always continues to select the driver-requested throttle opening DrvTVO as the throttle opening command tTVO, which contributes to the opening control of the electronically controlled throttle valve 32.
Therefore, while the vehicle speed limit control is not being executed, the engine 2 can be constantly output-controlled so as to realize the driver-requested driving force DrvTd, and normal driving can be performed as scheduled.

Next, the automatic transmission 3 will be described. The automatic transmission 3 is assumed to be a forward seven-speed multistage automatic transmission, and its transmission control is performed by the transmission controller 34.
Therefore, the actual vehicle speed VSP detected by the sensor 21 and the throttle opening degree command tTVO selected by the selection unit 18 are input to the transmission controller 34.
The transmission controller 34 controls the shift of the automatic transmission 3 from the actual vehicle speed VSP and the throttle opening command tTVO based on the shift pattern illustrated in FIG. 2 as follows.

FIG. 2 shows shift lines (numbers are shift stages) on which upshifts and downshifts should be performed between adjacent shift stages.
The transmission controller 34 determines the optimum gear position for the current operating state from the actual vehicle speed VSP and the throttle opening degree command tTVO based on the shift pattern of FIG.
Then, the transmission controller 34 automatically shifts the automatic transmission 3 from the currently selected shift speed to the optimum shift speed.

By the way, as described above, the throttle opening command tTVO is the smaller Min (DrvTVO, LmtTVO) of the driver requested throttle opening DrvTVO and the vehicle speed limiting target throttle opening LmtTVO (which is switched to the maximum value when the vehicle speed restriction is released). The same value,
When the vehicle speed limit is released, the throttle opening command tTVO is switched from a small target throttle opening LmtTVO for limiting the vehicle speed as shown at point A in FIG. 2 to a large driver required throttle opening DrvTVO as shown at point B in FIG. Sometimes.

In this case, as shown by the broken line in FIG. 4, at the time t1 when the vehicle speed restriction is released, a jump downshift from the seventh speed corresponding to tTVO = LmtTVO to the second speed corresponding to tTVO = DrvTVO occurs.
When the interlaced downshift is performed at a normal speed determined by hardware without speed change control, a large speed change shock occurs due to a large speed ratio change range, which becomes a large vehicle speed limit release shock.

In this embodiment, in order to solve this problem, the transmission controller 34 performs not only the above-described normal shift control but also the shift speed control targeted by the present invention when the vehicle speed limit is released. .
Therefore, the transmission controller 34 corresponds to the shift speed limiting means in the present invention.
For such shift speed control (shift speed limit), the transmission controller 34 further receives a vehicle speed limit operation signal Sop from the determination unit 11 and a kickdown signal Skd from the determination unit 17.
The transmission controller 34 executes the control program shown in FIG. 3 based on the vehicle speed limit operation signal Sop and the kick down signal Skd, and performs the speed control at the time of canceling the vehicle speed limit targeted by the present invention as follows. To do.

In step S11, it is checked whether or not the state where the vehicle speed limit operation signal Sop exists (ON) is switched to the state where the vehicle speed limit operation signal Sop disappears (OFF).
If the vehicle speed limit operation signal Sop does not change from ON to OFF, that is, if the vehicle speed limit control is continuing or not being executed, the speed control for the shock countermeasure is not performed when the vehicle speed limit is released. Therefore, the control is terminated as it is.

When it is determined in step S11 that the vehicle speed limit operation signal Sop has changed from ON to OFF, in step S12, the currently selected shift speed SHIFT causes the shock problem, and therefore the shift speed control according to the present invention is performed. Check if it is a low gear below the required setting gear SHIFTsp.
When it is determined in step S12 that the shift stage SHIFT does not cause the shock problem (the shift speed control according to the present invention is unnecessary) and is a shift stage higher than the set shift stage SHIFTsp,
In step S13, downshifting until SHIFT = SHIFTsp is permitted, and the downshifting is advanced at once without limitation of the shift speed.

When it is determined in step S12 that the shift stage SHIFT causes the shock problem (the shift speed control according to the present invention is required) and is a low-side shift stage that is equal to or lower than the set shift stage SHIFTsp, or the above-described step S13 is executed. After that
In step S14, it is determined whether the kick-down signal Skd is present or not in the kick-down state in which the accelerator pedal 23 is fully depressed (rapid acceleration request).

If not in the kick-down state, in step S15, it is checked whether or not the automatic transmission 3 is shifting.
If the speed is not being changed, it is checked in step S16 whether the actual vehicle speed VSP is a high vehicle speed that is equal to or higher than the set vehicle speed VSPs or a low vehicle speed that is less than that.
Here, the set vehicle speed VSPs is set to a lower limit vehicle speed that does not cause the above-mentioned shock problem even if the shift speed is increased.

When it is determined in step S14 that the vehicle is kicked down (rapid acceleration request), in step S17, the time change rate ΔTVO from LmtTVO to DrvTVO when the throttle opening command tTVO is released from the vehicle speed limit is set to the first ramp gradient ΔTVO (1). Limit to.
Here, the first ramp gradient ΔTVO (1) is made to correspond to the time change rate of the throttle opening command tTVO that achieves the downshift speed enabling the rapid acceleration requested by the driver by kickdown.

When it is determined in step S15 that the automatic transmission 3 is shifting, in step S18, the time change rate ΔTVO from LmtTVO to DrvTVO when the vehicle speed limit of the throttle opening command tTVO is released is calculated as the fourth ramp gradient ΔTVO (4 ).
Here, the fourth ramp gradient ΔTVO (4) is such that the throttle opening command tTVO does not reach the value crossing the next shift line during the shift before the above shift is completed, and the jump downshift is not performed. In correspondence with the time change rate of the throttle opening command tTVO, ΔTVO (4) = 0 is set in this embodiment, and the throttle opening command tTVO is held at a value immediately before the start of shifting during the shift.

When it is determined in step S16 that the actual vehicle speed VSP is higher than the set vehicle speed VSPs, in step S19, the time change rate ΔTVO from LmtTVO to DrvTVO at the time of release of the vehicle speed restriction of the throttle opening command tTVO is set to the second ramp. Limit to gradient ΔTVO (2).
Here, the second ramp gradient ΔTVO (2) is made to correspond to the time change rate of the fastest throttle opening command tTVO that can solve the shock problem in the high vehicle speed range.

When it is determined in step S16 that the actual vehicle speed VSP is a low vehicle speed less than the set vehicle speed VSPs, in step S20, the time change rate ΔTVO from LmtTVO to DrvTVO when the vehicle speed restriction of the throttle opening command tTVO is released is determined by the third ramp. Limit to gradient ΔTVO (3).
Here, the third ramp gradient ΔTVO (3) is made to correspond to the time change rate of the throttle opening command tTVO that can surely eliminate the shock problem even in the low vehicle speed range.
It should be noted that the impact of the shock is smaller in the high vehicle speed range than in the low vehicle speed range, and the problem caused by this can be solved relatively easily, and quick acceleration when the vehicle speed restriction is released is required. A relationship of ΔTVO (2)> ΔTVO (3) is provided between the ramp gradient ΔTVO (2) and the third ramp gradient ΔTVO (3).

In step S21, the time change rate ΔTVO from LmtTVO to DrvTVO when the throttle opening command tTVO is released is limited.
The first ramp gradient ΔTVO (1), the fourth ramp gradient ΔTVO (4), or the second ramp gradient ΔTVO (2) determined as described above in step S17, step S18, or step S19, or step S20, Or perform the process of limiting to the third ramp slope ΔTVO (3),
Based on the throttle opening command tTVO that rises from the target throttle opening LmtTVO for limiting the vehicle speed to the driver-requested throttle opening DrvTVO at the time change rate ΔTVO, shift (downshift) control at the time of releasing the vehicle speed restriction is executed.

According to the shift (downshift) control when the vehicle speed restriction is released according to the above-described embodiment, the following operational effects can be obtained.
When the throttle opening command tTVO is switched from the vehicle speed limiting target throttle opening LmtTVO at point A in FIG. 2 to the driver requested throttle opening DrvTVO at point B in FIG.
Conventionally, since the shift speed control as shown in FIG. 3 was not performed, as shown by the broken line in FIG. 4, at the time t1 when the vehicle speed restriction was released, from the seventh speed corresponding to tTVO = LmtTVO, the first speed corresponding to tTVO = DrvTVO A jump downshift to 2nd gear is performed at once.
When this interlaced downshift is performed at a normal speed determined by hardware without speed change speed control, a large speed change shock occurs due to a large speed ratio change width, and this becomes a large vehicle speed limit release shock.

By the way, in this embodiment, when the throttle opening command tTVO is switched from the target throttle opening LmtTVO for limiting the vehicle speed to the driver requested throttle opening DrvTVO when the vehicle speed restriction is released, the time change rate ΔTVO is illustrated by a solid line in FIG. (Step S17, step S18, step S19, or step S20).
Therefore, the shift (downshift) control at the time of releasing the vehicle speed restriction based on the throttle opening command tTVO that rises from the target throttle opening LmtTVO for vehicle speed limitation to the driver requested throttle opening DrvTVO at the time change rate ΔTVO (step S21). ),
As shown by the solid line in FIG. 4, it is possible to guarantee a sequential downshift from the seventh speed to the second speed, and the speed ratio change width of each shift becomes small, so that the shift shock can be reduced. The resulting vehicle speed limit release shock can be reduced.

The sequential downshift from the seventh speed to the second speed shown by the solid line in FIG. 4 will be described in detail.
While the throttle opening command tTVO rises from the target throttle opening LmtTVO for vehicle speed restriction LmtTVO (point A in FIG. 2) to the driver required throttle opening DrvTVO (point B in FIG. 2) at the above time change rate ΔTVO,
A downshift from the seventh speed to the sixth speed is performed at the instant t2 in FIG. 4 where the throttle opening command tTVO crosses the 6 ← → 7 shift line in FIG.
At the instant t3 in FIG. 4 where the throttle opening command tTVO crosses the 5 ← → 6 shift line in FIG. 2, a downshift from the sixth speed to the fifth speed is performed,
At the instant t4 in FIG. 4 where the throttle opening command tTVO crosses the 4 ← → 5 shift line in FIG. 2, a downshift from the fifth speed to the fourth speed is performed,
At the instant t5 in FIG. 4 where the throttle opening command tTVO crosses the 3 ← → 4 shift line in FIG. 2, a downshift from the fourth speed to the third speed is performed.
A downshift from the third speed to the second speed is performed at the instant t6 in FIG. 4 where the throttle opening command tTVO crosses the 2 ← → 3 shift line in FIG.

In order to achieve the above-described effect of reducing the shock, the speed change ratio is reduced by limiting the time change rate when the throttle opening command tTVO, which is the shift control factor of the automatic transmission 3, is released. I decided to do it,
Alternatively, the same effect can be obtained by performing a shift delay control on the shift schedule of the automatic transmission 3 and causing a sequential downshift in which the change ratio change width is reduced, thereby achieving the intended purpose. be able to.
However, as in the above-described embodiment, it is easier and more controllable to generate a sequential downshift with a small speed ratio change width by limiting the time change rate of the speed change control factor such as the throttle opening command tTVO. It is preferable in that the accuracy is high and the intended purpose can be surely achieved.

Further, in this embodiment, it is determined whether or not the shift stage SHIFT is a low-side shift stage that is equal to or lower than the set shift stage SHIFTsp (for example, the fifth speed) that requires the above-described shift speed control due to the shock problem (Step 5). S12),
If the gear position SHIFT is higher than the set gear position SHIFTsp (5th speed) (7th speed, 6th speed)
In step S13, downshifting up to SHIFT = SHIFTsp is permitted, and the downshifting is advanced at once without control of the shift speed. Therefore, the following effects can be obtained as shown in FIG.

  FIG. 5 is an operation time chart in the case where the downshift at the time when the vehicle speed restriction is released is the change from the seventh speed to the second speed, as in FIG. 4, and the broken line indicates the conventional shift control, that is, at the time t1 when the vehicle speed restriction is released. A shift state in which a downshift from a seventh speed corresponding to tTVO = LmtTVO to a second speed corresponding to tTVO = DrvTVO is performed at once.

On the other hand, in the present embodiment, as indicated by the solid line in FIG. 5, the shift speed SHIFT at the time t1 when the vehicle speed restriction is released is the seventh speed higher than the set shift speed SHIFTsp (5th speed).
The throttle opening command tTVO is increased step by step to the instant t1 so that the current downshift from the seventh speed to the set gear stage SHIFTsp (fifth speed) is performed at once at an instant t1 without speed limit restriction.
As a result, a jump shift from the seventh speed to the fifth speed is performed without going through the sixth speed.
However, the jump shift from the seventh speed to the fifth speed is a shift between the high-side gears having a small speed ratio change width, and thus does not cause the shock problem.
The jumping shift from the seventh speed to the fifth speed can shorten the total shift time from the seventh speed to the second speed when the vehicle speed restriction is released.

Then, since the downshift from the fifth speed thereafter causes the problem of the shock, the throttle opening command tTVO is set to the driver after the instant t1 in order to limit the shift speed as described above with reference to FIG. The time change rate ΔTVO when increasing toward the required throttle opening degree DrvTVO is limited as illustrated by the solid line in FIG. 5 (step S17, step S18, step S19, or step S20).
The shift (downshift) control at the time of releasing the vehicle speed limit based on the throttle opening command tTVO rising toward the driver requested throttle opening DrvTVO at the time change rate ΔTVO from the instant t1 (step S21),
As shown by the solid line in FIG. 5, it is possible to guarantee a sequential downshift from the fifth speed to the second speed, and the speed change range of each shift becomes smaller, so that the shift shock can be reduced. The resulting vehicle speed limit release shock can be reduced.

The sequential downshift from the fifth speed to the second speed shown by the solid line in FIG. 5 will be described in detail.
While the throttle opening command tTVO is increasing from the instant t1 to the driver requested throttle opening DrvTVO at the above time change rate ΔTVO,
At the instant t4 in FIG. 5 where the throttle opening command tTVO crosses the 4 ← → 5 shift line in FIG. 2, a downshift from the fifth speed to the fourth speed is performed,
At the instant t5 in FIG. 5 where the throttle opening command tTVO crosses the 3 ← → 4 shift line in FIG. 2, a downshift from the fourth speed to the third speed is performed.
A downshift from the third speed to the second speed is performed at the instant t6 in FIG. 5 where the throttle opening command tTVO crosses the 2 ← → 3 shift line in FIG.

Further, in this embodiment, since the release of the vehicle speed limit is performed in response to the kickdown, when it is determined in step S14 that the vehicle is in the kickdown state (rapid acceleration request), in step S17, the throttle opening command tTVO is set. The time change rate ΔTVO from LmtTVO to DrvTVO when the vehicle speed limit is released is limited to the first ramp gradient ΔTVO (1) as illustrated by the solid line in Fig. 6, and the throttle is opened at times other than during the kickdown indicated by the two-dot chain line in the same figure. To make it faster than the time change rate of degree command tTVO,
As shown in FIG. 6, the downshift from the seventh speed to the second speed when the vehicle speed restriction is released is a sequential downshift similar to that described above with reference to FIG. 4, but the first ramp gradient ΔTVO of the throttle opening command tTVO ( It is completed at a high speed determined by 1), and can enable rapid acceleration requested by the driver by kickdown.

Further, in this embodiment, when the downshift from the seventh speed to the second speed associated with the release of the vehicle speed restriction is determined in step S15 that the automatic transmission 3 is shifting, that is, the same conditions as in FIG. In FIG. 7 which is an operation time chart in FIG. 7, during the shift from the downshift command instant t2, t3, t4, t5 to the instant t2 ′, t3 ′, t4 ′, t5 ′ at which the corresponding shift ends (transmission ratio actual When the value is changing)
In step S18, the time change rate ΔTVO from LmtTVO to DrvTVO at the time of releasing the vehicle speed restriction of the throttle opening command tTVO is limited to the fourth ramp gradient ΔTVO (4) = 0, so that the following effects are obtained.

  In other words, the time change rate ΔTVO from LmtTVO to DrvTVO at the time of release of the vehicle speed restriction of the throttle opening command tTVO is set to the fourth ramp gradient ΔTVO (4) = 0 during the shift, so that the throttle opening command tTVO during this shift is set. Is maintained at the value immediately before the start of the shift, so that the throttle opening command tTVO does not reach the value crossing the next shift line and the jump downshift is performed before the ongoing shift is completed. The occurrence of shock due to this can be prevented.

  Although the fourth ramp gradient ΔTVO (4) is set to 0 in this embodiment, the fourth ramp gradient ΔTVO (4) reaches a value at which the throttle opening command tTVO crosses the next shift line during a shift. The desired purpose can be achieved if the gradient is as small as possible, and is not necessarily zero.

In this embodiment, it is determined whether the actual vehicle speed VSP when the vehicle speed restriction is released is a high vehicle speed that is equal to or higher than the set vehicle speed VSPs or a low vehicle speed that is less than the set vehicle speed VSPs (step S16).
If the vehicle speed is high, the time change rate ΔTVO from LmtTVO to DrvTVO when the throttle opening command tTVO is released is limited to the second ramp gradient ΔTVO (2) as shown by the solid line in FIG. 8 (step S19).
If the vehicle speed is low, the time change rate ΔTVO from LmtTVO to DrvTVO when the throttle opening command tTVO is released is limited to the third ramp gradient ΔTVO (3) as shown by the two-dot chain line in FIG. 8 (step S20). ,
Since the throttle opening command tTVO that rises from LmtTVO to DrvTVO at such a time change rate ΔTVO is used for the shift control of the automatic transmission 3, the following operational effects can be obtained.

In other words, at high vehicle speeds, the impact of the shock is less than at low vehicle speeds, and this problem can be solved relatively easily, and quick acceleration is required when the vehicle speed limit is released. The second ramp gradient ΔTVO (2) for the vehicle is made larger than the third ramp gradient ΔTVO (3) for the low vehicle speed, and the sequential downshift from the seventh speed to the second speed when the vehicle speed restriction is released is shown in FIG. As shown in FIG. 4, the vehicle can be completed earlier at high vehicle speeds than at low vehicle speeds.
As a result, it is possible to avoid the problem that the acceleration response is deteriorated in spite of the fact that the shift speed is reduced more than necessary at high vehicle speeds and quick acceleration is required when the vehicle speed limit is released, and the shock response is avoided. When the vehicle speed is low, the speed change can proceed at a speed that can surely reduce the shock.

By the way, in this embodiment, as the time change rate ΔTVO from LmtTVO to DrvTVO at the time of releasing the vehicle speed restriction of the throttle opening command tTVO, whether the actual vehicle speed VSP at the time of releasing the vehicle speed restriction is a high vehicle speed range or a low vehicle speed range In response to this, the second ramp gradient ΔTVO (2) for high vehicle speed and the third ramp gradient ΔTVO (3) for low vehicle speed were used properly.
Needless to say, the time change rate ΔTVO when the throttle opening degree command tTVO is released when the vehicle speed restriction is released may be continuously changed according to the actual vehicle speed VSP when the vehicle speed restriction is released.

In the above description, the case where the automatic transmission 3 is a stepped automatic transmission has been described. However, even when the automatic transmission 3 is a continuously variable transmission, the speed ratio change width when the vehicle speed restriction is released is If it is large, the above-mentioned shock problem occurs.
Therefore, the above-described idea of the present invention can be applied in the same manner even when the automatic transmission 3 is a continuously variable transmission, and the same operational effects can be achieved.

1 is a functional block diagram showing a vehicle speed limit control device for a vehicle provided with a vehicle speed limit release time shift control device according to an embodiment of the present invention. FIG. FIG. 2 is a diagram illustrating a shift pattern of the automatic transmission in FIG. FIG. 2 is a flowchart showing a shift speed control program executed when a transmission controller in FIG. FIG. 4 is an operation time chart showing the basic operation of the vehicle speed restriction releasing shift speed control shown in FIG. 3. FIG. FIG. 4 is a time chart showing another operation mode of the vehicle speed restriction releasing shift speed control shown in FIG. 3. FIG. FIG. 4 is a time chart showing still another operation mode of the vehicle speed restriction releasing shift speed control shown in FIG. 3. FIG. FIG. 4 is a time chart showing another operation mode of the vehicle speed restriction releasing shift speed control shown in FIG. 3. FIG. FIG. 5 is a time chart showing still another operation mode of the vehicle speed restriction releasing shift speed control shown in FIG. 3. FIG.

Explanation of symbols

1 Vehicle speed limit control device
2 Engine
3 Automatic transmission
11 Vehicle speed limit operation determination section (Limited vehicle speed setting means: Vehicle speed limit release means)
12 Target driving force calculation unit for limiting vehicle speed (driving force limiting means)
13 Target throttle opening calculator for vehicle speed limitation
14 Meter display signal generator
15 Driver required driving force calculator
16 Driver required throttle opening calculation section
17 Kickdown judgment part
18 Throttle opening command selector
21 Vehicle speed sensor (vehicle speed detection means)
22 Steering wheel
22a Speed limit control switch group
23 Accelerator pedal
23a Accelerator position sensor
24 Engine rotation sensor
31 Meter panel
31a Speed limit display
32 Electronically controlled throttle valve
33 Motor
34 Transmission controller (shift speed limiting means)

Claims (4)

A vehicle speed detecting means for detecting an actual vehicle speed of a vehicle having a power train composed of a prime mover and an automatic transmission that transmits power from the prime mover to drive wheels;
Limit vehicle speed setting means for setting a limit vehicle speed as a vehicle speed upper limit value;
Driving force limiting means for limiting the wheel driving force so that the actual vehicle speed does not exceed the limited vehicle speed in response to signals from these means;
In a vehicle speed restriction control device comprising vehicle speed restriction release means for releasing the vehicle speed restriction by the driving force restriction means when a predetermined condition is satisfied ,
The shift of the automatic transmission accompanying the release of the vehicle speed limit is basically performed under a predetermined shift speed limit, but at the beginning of the shift from the speed ratio immediately before the release of the vehicle speed limit to the speed ratio after the release of the vehicle speed limit, Shift speed limiting means for limiting the shift speed with respect to the shift from the predetermined speed ratio to the speed ratio after the vehicle speed limit is released without limiting the speed to a predetermined speed ratio at which sudden gear change is allowed. A shift control device for an automatic transmission at the time of releasing a vehicle speed limit, characterized in that it is provided. A vehicle speed detecting means for detecting an actual vehicle speed of a vehicle having a power train composed of a prime mover and an automatic transmission that transmits power from the prime mover to drive wheels;
Limit vehicle speed setting means for setting a limit vehicle speed as a vehicle speed upper limit value;
Driving force limiting means for limiting the wheel driving force so that the actual vehicle speed does not exceed the limited vehicle speed in response to signals from these means;
In a vehicle speed restriction control device comprising vehicle speed restriction release means for releasing the vehicle speed restriction by the driving force restriction means when a predetermined condition is satisfied,
The shift of the automatic transmission associated with the release of the vehicle speed limit is performed under a predetermined shift speed limit. When the shift speed is limited, a shift control factor of the automatic transmission that switches according to the release of the vehicle speed limit is set. The shift speed is limited by gradually changing from the value immediately before the switching to the value after the switching to contribute to the shift control, and the shift control factor is changed from the value immediately before the switching to the value after the switching. A shift control device for an automatic transmission at the time of release of the vehicle speed limitation, characterized by further comprising a shift speed limiting means for further reducing the speed to be changed during the shift of the automatic transmission. In the shift control device of the automatic transmission at the time of releasing the vehicle speed restriction according to claim 2 ,
The shift speed limiting means holds the shift control factor at a value immediately before the start of shift during the shift of the automatic transmission, thereby realizing a further decrease in the change speed of the shift control factor during the shift. A shift control device for an automatic transmission at the time of releasing a vehicle speed limit. A vehicle speed detecting means for detecting an actual vehicle speed of a vehicle having a power train composed of a prime mover and an automatic transmission that transmits power from the prime mover to drive wheels;
Limit vehicle speed setting means for setting a limit vehicle speed as a vehicle speed upper limit value;
Driving force limiting means for limiting the wheel driving force so that the actual vehicle speed does not exceed the limited vehicle speed in response to signals from these means;
In a vehicle speed restriction control device comprising vehicle speed restriction release means for releasing the vehicle speed restriction by the driving force restriction means when a predetermined condition is satisfied,
The shift of the automatic transmission accompanying the release of the vehicle speed limit is performed under a predetermined shift speed limit. When the shift speed is limited, the higher the vehicle speed at the release of the vehicle speed limit, the higher the vehicle speed limit. A shift control device for an automatic transmission at the time of releasing a vehicle speed limit, characterized in that shift speed limiting means for reducing the degree of the shift speed limit with respect to the shift associated with the release of the vehicle is provided .

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