JPH08152062A - Shift control device for automatic transmission - Google Patents

Abstract

PURPOSE: To provide a shift control device for an automatic transmission which is constituted in such a manner that by releasing a shift hold control under a given condition, even during cornering, the feeling of physical disorder of a driver is prevented from generation and drivability of a vehicle is improved. CONSTITUTION: A speed change control device for an automatic transmission comprises a curve running detecting means A to detect the curve running state of a vehicle; a means B to hold a speed during cornering to forcibly hold a speed at a constant value while the curve running state of a vehicle is detected by a curve running detecting means A; and a running resistance detecting means C to detect a value related to running resistance of a vehicle. A first speed holding releasing means D is provided to release holding of a speed by the means B to hold a speed during cornering when a value related to running resistance detected by the running resistance detecting means C exceeds a first given value while a speed is held by the means B to hold a speed during cornering. When running resistance exceeds a given value, speed holding control is released and by allowing kick down, vehicle running performance is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for an automatic transmission, and more particularly to an improvement in shift control during curve traveling (hereinafter also referred to as cornering).

[0002]

2. Description of the Related Art Conventionally, in a shift control device for an automatic transmission for a vehicle, there is a technique for detecting during cornering and performing automatic shift control in accordance with cornering characteristics, as disclosed in Japanese Examined Patent Publication No. 3-69023. Fair 6-4734
No. 8 publication and the like. An object of these conventional techniques is to avoid deterioration of vehicle stability due to a sudden change in driving force due to a downshift during cornering.

More specifically, the above Japanese Patent Publication No. 3-69.
The device disclosed in Japanese Patent No. 023 discloses only when the degree of cornering (value corresponding to lateral acceleration) is equal to or more than a predetermined value, that is,
When the front-back frictional force of the tire has no margin (the tire easily slips sideways), downshift is prohibited to maintain the stability of the vehicle.

In Japanese Patent Publication No. 6-47348, the cornering is detected by the steering angle of the steering wheel, and in a region where the driving force is large, such as a kick down region, a larger driving force is generated by downshifting. The downshift is prohibited even in such an area because the vehicle stability will be deteriorated. In any of the conventional examples, it is possible to avoid a sudden change in the behavior of the vehicle during cornering and improve the stability of the vehicle.

[0005]

However, in the above-mentioned conventional technique, the following problems may occur in a traveling state with a large traveling resistance such as traveling uphill. That is, at the corner with a climbing gradient of about 10% shown in FIG.
Assume that you have entered at high speed. The driver then depresses the accelerator pedal in an attempt to accelerate as he / she approaches the exit of the corner. However, since the running resistance is large due to the influence of the climbing slope and the acceleration in the third speed is maintained by the downshift prohibition control during cornering, the vehicle does not accelerate as expected.

Therefore, the driver feels uncomfortable and unsatisfied that the vehicle does not move as intended.
It should be noted that, in most of the automatic transmissions currently used in the market, the shift characteristics can be changed by the driver's operation. For example, in the case of a 4-speed automatic transmission, the D range for normal running [shift control using all the four speed stages], it is desired to cancel only the 4th speed OD [overdrive] cancel range [ie, 3 range] ], 1-
It is possible to change the range such as two ranges where only the second speed is changed by switching the select lever. However, with this device, the driver has to operate the select lever, so that the driver is bothered and the easy drive cannot be achieved.

The present invention has been made in view of such a conventional situation, and even if the vehicle is cornering, the shift hold (downshift prohibition) control is released under a predetermined condition so that the driver feels uncomfortable. It is an object of the present invention to provide a shift control device for an automatic transmission that solves the above problem and improves the drivability of a vehicle. Another object of the present invention is to improve the accuracy and simplification of the shift control device to make it more practical.

[0008]

Therefore, according to the invention described in claim 1, as shown in FIG. 1, a curve traveling detecting means A for detecting a curve traveling state of the vehicle and the curve traveling detecting means A are used. A curve shift speed holding means B for forcibly holding the shift speed constant while the vehicle is running on a curve; a running resistance detecting means C for detecting a value related to the running resistance of the vehicle; When the value related to the running resistance detected by the running resistance detecting means C becomes equal to or more than a first predetermined value while the gear position is held by the curve speed holding means B, the curve time shifting is performed. Step holding means B
And a first speed-gear holding release means D for releasing the holding of the gear position by the above.

According to the second aspect of the present invention, as shown in FIG. 2, a curve traveling detection means A for detecting a curve traveling state of the vehicle and a curve traveling state of the vehicle are detected by the curve traveling detection means A. While the vehicle is on the curve, the gear shift speed holding means B for forcibly holding the gear speed, the running resistance detection means C for detecting a value related to the running resistance of the vehicle, and the value related to the driver's intention to accelerate are displayed. While the gear shift is held by the acceleration intention detecting means E for detecting and the curve shift speed holding means B, the value related to the running resistance detected by the running resistance detecting means C is not less than a first predetermined value. And the value detected by the acceleration intention detecting means E is equal to or more than the second predetermined value, the second speed-gear holding release for releasing the holding of the speed-gear by the curve gear speed-gear holding means B Means F and In was constructed.

According to the third aspect of the present invention, as shown in FIG. 3, a curve traveling detecting means A for detecting a curve traveling state of the vehicle and a curve traveling state of the vehicle are detected by the curve traveling detecting means A. While the vehicle is on the curve, the shift speed holding means B for forcibly holding the shift speed, the acceleration detecting means G for detecting the longitudinal acceleration of the vehicle, and the curve shift speed holding means B for holding the shift speed. While
A third shift speed holding release means H for releasing the holding of the shift speed by the curve shift speed holding means B when the vehicle longitudinal acceleration detected by the acceleration detecting means G becomes a third predetermined value or less. , And are configured to include.

According to the fourth aspect of the present invention, as shown in FIG. 4, a curve traveling detecting means A for detecting a curve traveling state of the vehicle, and the curve traveling state of the vehicle is detected by the curve traveling detecting means A. While the vehicle is on the curve, the gear shift speed holding means B forcibly holding the gear speed constant, the acceleration detection means G for detecting the longitudinal acceleration of the vehicle, and the acceleration intention for detecting a value related to the driver's acceleration intention. When the vehicle front-rear direction acceleration detected by the acceleration detecting means G is equal to or less than a third predetermined value while the shift speed is held by the detecting means E and the curve shift speed holding means B, and A fourth shift speed holding release means I for releasing the holding of the shift speed by the curve shift speed holding means B when the value detected by the acceleration intention detecting means E is not less than a second predetermined value;
It was composed including.

According to the fifth aspect of the invention, the value related to the running resistance of the vehicle is configured as a value related to the slope of the road surface or the slope resistance. According to the invention of claim 6,
The second predetermined value is set depending on the rotation speed of the engine connected to the automatic transmission.

[0013]

In the invention according to claim 1 having such a structure, even when the vehicle is traveling on a curve, when the traveling resistance is equal to or more than a predetermined value (for example, when traveling on an uphill or when the load is large), the vehicle travels on a curve. By releasing the gear speed maintenance control by the gear speed holding means and allowing kickdown etc., the vehicle running performance is improved and the driver feels uncomfortable that the vehicle does not move as intended. Try not to let me. In this case, since the cancellation of the gear speed maintenance control is performed based on the value related to the running resistance, it is not necessary to detect the vehicle acceleration with respect to the invention described in claim 3, so the control response It is possible to increase the sex.

According to the second aspect of the present invention, only when the running resistance exceeds a predetermined value while the vehicle is traveling on a curve and the driver intends to accelerate, the gear speed maintaining control by the on-curve gear speed maintaining means is performed. By canceling, that is, after confirming the driver's willingness to accelerate, permitting kickdown, etc., the driver feels uncomfortable due to canceling the shift speed holding control during curve more than necessary. To prevent deterioration of vehicle stability during occurrence and cornering.

According to the third aspect of the present invention, even when the vehicle is decelerating more than a predetermined amount even during traveling on a curve (for example, when traveling on an uphill or when the load is large, etc.), the shift during curve is performed. Release the gear speed maintenance control by the gear holding means,
By permitting kickdown, etc., the driving performance of the vehicle will be improved and the driver will not feel uncomfortable or unhappy that the vehicle will not move as intended. It should be noted that, compared with the invention described in claim 1, in that the vehicle acceleration is directly detected, it is easier to detect the discomfort caused between the driver's operation and the behavior of the vehicle with higher accuracy.

According to the invention described in claim 4, only when the vehicle decelerates more than a predetermined amount while the vehicle is traveling on a curve and the driver intends to accelerate, the control for maintaining the gear position by the curve gear holding means is canceled. That is, after confirming the driver's willingness to accelerate, permitting kickdown, etc., and causing the driver to feel uncomfortable due to the excessive release of the gear speed holding control. Also, the deterioration of vehicle stability during cornering is suppressed.

According to the fifth aspect of the present invention, since the value related to the running resistance of the vehicle is configured as the value related to the road surface slope or the slope resistance, the uphill running condition of the vehicle can be detected with high accuracy. Thus, the control accuracy of the device can be improved. According to the invention of claim 6,
Since the second predetermined value is set depending on the rotation speed of the engine connected to the automatic transmission, the driver's intention to accelerate can be detected with higher accuracy.

[0018]

Embodiments of the present invention will be described below. Figure 5
FIG. 1 is a system configuration diagram of an embodiment of a shift control device for an automatic transmission according to the present invention. In FIG. 5, an automatic transmission 2 is provided on the output side of an engine 1 mounted on a vehicle (not shown). The automatic transmission 2 includes a fluid type torque converter 3 interposed on the output side of the engine 1, a gear type transmission 4 connected to the engine 1 via the fluid type torque converter 3, and a gear type transmission 4 of the gear type transmission 4. Combination of various speed change elements inside
And a hydraulic actuator 5 for performing an opening operation.

The operating hydraulic pressure for the hydraulic actuator 5 is controlled through various electromagnetic valves (not shown), and the automatic transmission control unit 6 shifts gears to a target shift speed by a combination of ON / OFF of the various electromagnetic valves. . Signals from various sensors are input to the automatic transmission control unit 6. As the various sensors, there is provided a throttle sensor 8 for detecting an opening TVO of a throttle valve 7 which is interposed in an intake system of the engine 1 and opens and closes in conjunction with an accelerator pedal (not shown).

Further, the rotation speed N of the output shaft of the automatic transmission 2
A vehicle speed sensor 9 is provided as vehicle speed detecting means for detecting the vehicle speed VSP by detecting o. Since the vehicle acceleration is detected based on the time rate of change of the vehicle speed VSP, the vehicle speed sensor 9 also corresponds to acceleration detecting means. Further, the brake switch 10 indicating the operation / non-operation of the brake, the lateral acceleration of the vehicle (hereinafter, also referred to as lateral G).
A lateral G sensor 11 is provided as a curve traveling detecting means for detecting the.

Then, the automatic transmission control unit 6 determines a target shift speed based on signals from the various sensors, and outputs a shift signal for turning on / off the electromagnetic valve according to the target shift speed. , Control the shift operation in the automatic transmission 2. Next, a first embodiment of the automatic shift control according to the present invention will be described with reference to the flowcharts of FIGS. Incidentally, in the present embodiment, a curve traveling detecting means, a curve shift speed holding means, a traveling resistance detecting means,
As shown in the flow charts of FIGS. 6 to 11, the control unit 6 is provided with the functions of the acceleration intention detecting means, the acceleration detecting means, and the first to fourth shift speed holding releasing means by software.

First, in step 1 (denoted as S1 in the figure; the same applies hereinafter), input processing such as reading detection signals from various sensors is performed. In steps 2 to 15, throttle operation speed ΔTVO1 (time change rate of throttle opening TVO), vehicle acceleration ΔVSP1 (time change rate of vehicle speed VSP), and vehicle speed VSP1 used to determine a deceleration request and set a gear position are set. I do.

In step 2, the deceleration request flag F is set to 1 when the vehicle is in the deceleration request state, as will be described later.
_{When the} flag F ₁ is φ,
Proceeding to step 7, the throttle operation speed ΔTVO
1, the latest data (ΔTVO, ΔVSP, VSP) is set to the acceleration ΔVSP1 and the vehicle speed VSP1 (= VSP).

On the other hand, when the flag F ₁ is 1, the routine further proceeds to step 3 to discriminate a curve traveling flag F ₂ which is set to 1 while the vehicle is traveling on a curve as described later. When the deceleration request flag F ₁ is 1 and the curve traveling flag F ₂ is φ (non-curve traveling state), the routine proceeds to step 4.

At step 4, the previously set operation speed Δ
The smaller one of TVO1 and the latest calculated operation speed ΔTVO is set as the current operation speed ΔTVO1. The operating speed ΔTVO1, the operation speed ΔT from 1 is set to the deceleration request flag F ₁ to the present time
It is set as the minimum value of VO, and, for example, when the throttle is rapidly closed and then held fully closed, the operation speed ΔTVO at the time of the sudden closing is continuously held thereafter. It will be.

Therefore, even in the state of being fully closed after the sudden closing operation, the sudden closing operation in which a shift request to a lower speed step is strong as a shift step set based on the throttle operation speed ΔTVO1 is performed. The corresponding low speed can be held, and the engine braking effect by the downshift can be reliably obtained even when the throttle operation is instantaneously performed.

Further, the acceleration ΔV of the same step 4, the 1 is set to the deceleration request flag F ₁ to the present time
The minimum value of SP is set as the acceleration ΔVSP1 used for setting the shift speed for deceleration control. As a result, even if the deceleration becomes small immediately after the sudden deceleration, the required shift speed at the time of the sudden deceleration can be continuously maintained, and the engine braking effect due to the downshift can be reliably obtained.

In the next step 5, the deceleration request flag F ₁
The maximum value of the vehicle speed VSP from the time 1 is set to the present time is set as the vehicle speed VSP1 used for setting the shift speed for deceleration control. As a result, in deceleration from a high vehicle speed in the later-described gear setting, the gear set for deceleration control is held at a relatively high speed side, and excessive engine braking is prevented. It will be possible.

On the other hand, in step 3, the curve running flag F ₂
Is determined to be 1, the process proceeds to step 6, and the previous data is set as it is to the throttle operation speed ΔTVO1, the acceleration ΔVSP1, and the vehicle speed VSP1 (= VSP), that is, the current gear is held. Surely prohibit downshifts and upshifts,
By avoiding sudden changes in the behavior of the vehicle during cornering and maintaining vehicle acceleration, the stability and drivability of the vehicle during cornering are improved.

After the input processing is completed, the process proceeds to the flowchart of FIG. 7. In step 11, the shift position by the select lever (not shown) is used for automatic shift control for all shift speeds (1st speed to 4th speed in this embodiment). It is determined whether or not it is in the D range. If the vehicle is in the D range, the process proceeds to step 12, where the vehicle speed VS is based on a flat road.
The throttle opening (R / LTVO) corresponding to the road load (Road Load) set according to P is compared with the latest detected throttle opening TVO. In addition, R / LT
In other words, VO is the throttle opening at which the acceleration becomes 0 at the vehicle speed VSP.

When the throttle opening TVO is less than the road load equivalent, step 13
And the throttle operation speed ΔTVO1 is a predetermined value 1
It is determined whether (negative value) or less. The throttle operation speed ΔTVO (time change rate of the throttle opening TVO) is calculated with the change in the opening direction of the throttle being positive and the change in the closing direction being negative.

The predetermined value 1 to be compared with the throttle operation speed ΔTVO1 corresponds to the characteristic of the second required shift speed set based on the throttle operation speed ΔTVO1 and the vehicle speed VSP1 as described later. It is preferable to change according to VSP1. Specifically, it is preferable to use the third speed ⇔ the fourth speed line in the characteristic of the second required shift speed. If the throttle opening TVO is less than the load equivalent to the road load and the throttle operation speed ΔTVO1 is less than or equal to the predetermined value 1, it is determined that the deceleration request is made due to the closing operation of the throttle, and the process proceeds to step 16. Then, the flag F ₁ indicating whether the vehicle is in the deceleration request state is set to 1 corresponding to the deceleration request state.

On the other hand, when it is not determined that the deceleration is required by the determinations in steps 12 and 13, the process proceeds to step 14 and it is determined whether the brake switch 10 is ON or OFF. If the brake switch 10 is ON, the driver When the brake is being operated by, the procedure proceeds to step 15. In step 15, it is judged whether or not the vehicle acceleration ΔVSP1 (time change rate of the vehicle speed VSP) is less than or equal to a predetermined value 2 (negative value).

The acceleration ΔVSP is calculated by subtracting the detection value of the vehicle speed VSP from the latest detection value a predetermined time before, and is calculated as a positive value when the vehicle is accelerated and a negative value when the vehicle is decelerated. And Therefore,
The determination in step 15 is to determine whether or not the deceleration of the vehicle is equal to or higher than a predetermined value. The predetermined value 2 to be compared with the acceleration ΔVSP1 should be changed according to the vehicle speed VSP1 so as to correspond to the characteristic of the third required shift speed set based on the acceleration ΔVSP1 and the vehicle speed VSP1 as described later. Is preferred. Specifically, it is preferable to use the third speed ⇔ the fourth speed line in the characteristic of the third required shift speed.

When it is determined in step 15 that the acceleration ΔVSP1 is less than or equal to the predetermined value 2, the vehicle is decelerating due to the braking operation. At this time, the process proceeds to step 16 and the deceleration request flag F is set. It is set to 1 indicating a deceleration request state _1. That is, the deceleration request flag F
₁ indicates that the deceleration request is determined based on the throttle operation (the driver's intention to decelerate) and / or the deceleration request is determined based on at least one of the time when the vehicle is decelerated with the brake operation. Will be set.

After performing the deceleration request determination process as described above, the process proceeds to the flowchart of FIG. Step
In step 21, the deceleration request flag F ₁ is discriminated. When the deceleration request flag F ₁ is set to ₁ , the process proceeds to step 22 and the curve traveling flag F ₂ showing whether or not the vehicle is traveling in a curve is discriminated. I do.

When φ indicating the non-curve traveling state is set in the curve traveling flag F ₂ , step 23
Then, the process proceeds to step S4 and it is determined whether or not the lateral G (lateral acceleration) detected by the lateral G sensor 11 is a predetermined value 4 or more. If the lateral G is equal to or greater than the predetermined value 4, it is determined that the vehicle is traveling on a curve, the process proceeds to step 24, the curve traveling flag F ₂ is set to 1, and then the process proceeds to the flowchart of FIG.

In step 22, the curve running flag F ₂
When φ indicating the non-curved running state is set in and the lateral G is determined to be less than the predetermined value 4 in step 23, the vehicle is in the non-curved running state, so the routine proceeds to step 29, and the timer T ₁ is set. It is determined whether or not the predetermined value 3 is exceeded. If the timer T ₁ is equal to or less than the predetermined value 3, the process proceeds to step 30 and the timer T ₁ is incremented by 1.

When the timer T ₁ exceeds the predetermined value 3, that is, when the deceleration request state is detected and the deceleration request flag F 1 is set to ₁ and the elapsed time exceeds the predetermined time, After step 27, the flag F ₁ is reset to zero and the timer T ₁ is reset to zero. The zero reset processing of the flag F ₁ by such timer T _1, is continued unnecessarily shift control corresponding to the deceleration request, to prevent the transition to the normal shift control is delayed. That is, when the flag F ₁ is set to ₁ , the shift control for effecting the engine braking is executed as will be described later, but after the shift control is continued for a predetermined time or longer, The normal shift control based on the engine load and the throttle opening is restored, and it is possible to prevent the driver from feeling uncomfortable without performing upshifts or kickdowns even after deceleration.

On the other hand, when it is judged in the step 22 that the flag F ₂ is set to 1, the step
Proceeding to 25, by determining whether the lateral G is smaller than the predetermined value 5, it is determined whether the curve traveling is completed (escape). In addition, the actual lateral G
The predetermined value 4 compared with and the predetermined value 5 compared with the actual lateral G to determine the end (escape) of the curve are the predetermined value 4>
There is a predetermined value of 5.

If it is determined that the lateral G is smaller than the predetermined value 5 and the curve traveling is completed, after resetting all the flags F ₁ , F ₂ and timer T ₁ ,
Proceed to the flowchart of FIG. On the other hand, when it is determined that the lateral G is equal to or more than the predetermined value 5 and the curve traveling is continued, the routine proceeds to step 31, the flowchart of FIG. 10 is executed, and the curve traveling flag F ₂ is set.

Here, based on the flowchart of FIG.
The setting of the curve running flag F ₂ will be described. In step 51, the gradient (ii) is calculated by executing the flowchart of FIG. 11 described later. Note that FIG. 11 corresponds to the running resistance detecting means of the present invention. In step 52, a predetermined throttle opening QFLTTVO installed corresponding to the engine rotation speed Ne is calculated with reference to the map shown in the flow.

In step 53, the gradient (ii) is compared with a predetermined gradient (IICUV). If the gradient (ii)> the predetermined gradient (IICUV), the process proceeds to step 54. In step 54, the current throttle opening TVO, the QFLTTVO, and
To compare. The step 54 corresponds to the acceleration intention detecting means of the present invention. And if TVO> QFLTTVO,
Currently, the vehicle is traveling uphill over a predetermined grade, and the driver judges that he is stepping on the accelerator to request acceleration.
In step 55, the curve traveling flag F ₂ is set to φ (non-curve traveling determination). Since this routine is executed when the curve is determined in step 23,
The current vehicle running condition is that the vehicle is traveling on a curve, and
Since the driver is requesting acceleration while climbing over a predetermined slope, setting the curve traveling flag F ₂ to φ even during traveling on a curve enables shifting during traveling on a curve. The control (shift hold control) is released, downshifting (kick down), etc. are allowed, and the driver's acceleration request is prioritized so that the driver does not accelerate even if he depresses the accelerator (or the vehicle speed decreases. This is because the occurrence of a feeling of strangeness such as “going away” and the deterioration of traveling performance are suppressed.

On the other hand, if it is determined in step 53 that the gradient (ii) ≦ predetermined gradient (IICUV), TVO ≦ QF in step 54
If it is determined to be LTTVO, the routine proceeds to step 56, where the curve traveling flag F ₂ is set to 1 (curve traveling determination). That is, in such a case, the grade of uphill is not so large, and there is also no strong acceleration request from the driver. Therefore, it is possible to maintain the curve traveling judgment, thereby lowering the vehicle stability due to the occurrence of an inadvertent downshift. I try to suppress it.

In this embodiment, the curve running flag F ₂ is set as described above. This flow is the second aspect of the present invention.
It corresponds to the gear position holding release means. It should be noted that step 54 may be omitted, and in this case, it corresponds to the first gear position holding release means of the present invention. Next, the flowchart of FIG. 9 will be described.

In step 41, the deceleration request flag F ₁
If the flag F ₁ is set to ₁ , the process proceeds to step 42 and the curve running flag F ₂ is determined. The deceleration request flag F ₁ is 1, and
If the curve traveling flag F ₂ is φ, that is, if there is a deceleration request and the vehicle is not traveling in the curve at all (for example, during deceleration before entering the curve), the routine proceeds to step 43, where the throttle operation speed ΔTVO1 and the vehicle speed VSP1 are set. The second required shift speed (second shift speed request) is calculated based on the above.

The calculation of the required shift speed in step 43 is performed in advance by calculating the throttle operation speed ΔTVO1 and the vehicle speed VSP1.
It is performed with reference to a map as shown in the flowchart in which the shift speed is stored according to Here, the characteristic is such that the lower speed stage is selected as the throttle operation speed ΔTVO increases to the negative side (the higher the throttle closing operation speed is), and further, the low vehicle speed side and the high vehicle speed side have a comparatively large characteristic. The gear on the high speed side is selected. On the high vehicle speed side, a relatively high speed is selected to avoid excessive engine braking due to downshifting and overrev, and on the low vehicle speed side, engine braking due to downshifting is effective. A relatively high speed stage is selected in order to avoid overshooting and to allow a smooth stop.

In the next step 44, the vehicle acceleration ΔVS
A third required shift stage (third shift stage request) is calculated based on P1 and the vehicle speed VSP1. The calculation of the required shift speed in step 43 is performed with reference to a map as shown in the flowchart in which the shift speed is stored in advance according to the vehicle acceleration ΔVSP and the vehicle speed VSP.

Here, the characteristic is that the lower the speed is, the higher the acceleration becomes to the negative side (the greater the deceleration of the vehicle), and the lower the vehicle speed side is. With respect to the vehicle speed side, a relatively high speed gear stage is selected. Further steps
At 45, the first required shift speed (first shift speed request) corresponding to the shift speed of the normal shift control is calculated based on the vehicle speed VSP and the throttle opening TVO (engine load).

The calculation of the required shift speed in step 45 is performed with reference to a map as shown in the flowchart in which the shift speed is stored in advance according to the vehicle speed VSP and the throttle opening VSP. The shift map is set such that, as long as the vehicle speed VSP is the same, the smaller the throttle opening (engine load), the more likely it is to upshift.
Note that the map is a normal shift control map, and kick down control (see the portion parallel to the vehicle speed indicated by the broken line in the figure)
Is also possible.

Then, in step 46, the first, second, and third required shift speeds are compared, and the shift speed which is the lowest speed among these is set as the final target shift speed,
While the engine braking is activated by shifting to the target shift speed, kickdown control can also be performed during cornering and when traveling over a predetermined slope. ing.

In step 47, a shift signal is output to the electromagnetic valve so that the actual shift position coincides with the set target shift speed. On the other hand, when it is judged in step 41 that the deceleration request flag F ₁ is φ, the routine proceeds to step 48, where the fourth speed, which is the highest speed stage, is set as the second requested gear stage, and in the next step 49, Similarly, the fourth speed, which is the highest speed, is set as the third required speed. By setting the highest speed, it is possible to prevent the target speed from being set at least to the speed lower than the first required speed when the routine proceeds to step 46, and substantially, the deceleration request flag F is set.
_{When 1} is φ, the shift control (that is, the normal shift control) is performed based on the first required shift speed.

In step 41, the curve running flag F ₂
When it is determined that 1 is set to 1, the steps 42 to 47 are skipped and the process proceeds to step 48 so that the target shift speed is not updated. That is, even if the deceleration request flag F ₁ is set to ₁ , if the curve running flag F ₂ is set to 1, the gear position up to that point is held and the gear shift is performed during the curve running. As a result, it is possible to prevent the driving force from changing, and it is possible to secure traveling stability when traveling on a curve. Therefore, when a vehicle enters a curve while being controlled to a lower speed than usual in response to a deceleration request for entering the curve, the vehicle travels while being held at the lower speed.

As described above, in this embodiment, the shift is held in principle during cornering. However, if there is a running resistance equal to or more than a predetermined value even during cornering (such as when traveling on an uphill road), shift hold control is performed. By releasing it and allowing downshifts, etc., it is possible to respond to the driver's acceleration request, eliminating the discomfort and dissatisfaction that the vehicle does not move as the driver intended. ,
As a result, the vehicle climbing performance during cornering can be improved. As in the present embodiment, if the driver's intention to accelerate is confirmed and then downshifting or the like is permitted, an uncomfortable feeling due to the shift hold control being canceled more than necessary, and cornering. It is possible to suppress deterioration of running performance of the inside vehicle.

By the way, the above-mentioned gradient (ii) is calculated by executing the flowchart of FIG. Where the figure
The flowchart of 11 will be described. In step 61, referring to the map in the flowchart, the target engine torque T is calculated from the throttle opening TVO and the engine speed Ne.
Ask for g-eng. In step 62, the output torque To (= Tg-eng × gear ratio) of the output shaft of the automatic transmission 2 is obtained.

In step 63, the running resistance RL (= rolling resistance + air resistance) is calculated from the relational expression f (vsp) with the predetermined vehicle speed VSP. In step 64, the acceleration resistance MA
(= VSP '× M, VSP' is the time partial differential value of the vehicle speed,
M is the vehicle weight). In step 65, the gradient (ii) is
It is calculated from the following formula.

Ii = [To * K- (MA + RL)] / WK is a conversion coefficient from torque to driving force. W is vehicle weight × gravitational acceleration. Next, regarding the setting of the curve running flag F ₂ , a setting method other than that shown in the flowchart of FIG. 10 will be described according to the flowchart of FIG.

In step 71, the gradient (ii) is calculated from the above-mentioned diagram.
Calculation is carried out by executing the flowchart of 11. In step 72, the pressure Boost in the intake system of the engine 1 is A / D converted and obtained via an intake pressure sensor (not shown). In step 73, the gradient (ii) is compared with a predetermined gradient (IICUV). If the gradient (ii)> the predetermined gradient (IICUV), the process proceeds to step 74.

In step 74, the Boost and a predetermined value BS
Compare with TCV. If Boost> BSTCV, it is determined that the vehicle is currently traveling on an uphill over a predetermined grade and the driver is stepping on the accelerator to request acceleration, and the curve traveling flag F ₂ is set to φ. Yes (non-curve running judgment). Since this routine is executed when the curve is determined in step 23, the current vehicle traveling state is that the vehicle is traveling on a curve and is traveling uphill with a predetermined gradient or more, and the driver Since the vehicle is in the acceleration request state, even during the curve running, the curve running flag F ₂ is set to φ to cancel the shift control (shift hold control) during the curve running and downshift. To prioritize the driver's acceleration request, thereby suppressing the occurrence of discomfort that the driver does not accelerate even if he depresses the accelerator (or the vehicle speed decreases), and the deterioration of driving performance is suppressed. Is.

On the other hand, if it is determined in step 73 that the gradient (ii) ≦ predetermined gradient (IICUV), then in step 74 TVO ≦ BS
If it is determined to be TCV, proceed to step 76,
The curve traveling flag F ₂ is set to 1 (curve traveling determination). In other words, in such a case, the uphill slope is not so large, and there is no strong acceleration request from the driver, so the curve traveling judgment (shift hold control) is maintained, so that an uncomfortable feeling due to an inadvertent downshift occurs. Avoid occurrence and deterioration of vehicle stability.

Further, regarding the setting of the curve running flag F ₂ , a setting method other than those shown in the flow charts of FIGS. 10 and 12 will be described with reference to the flow chart of FIG. In step 81, a predetermined throttle opening QFLTTVO set corresponding to the engine rotation speed Ne is calculated with reference to the map shown in the flow. In step 82, the vehicle front-rear direction acceleration dVSP is obtained based on the signal from the vehicle speed sensor 9 and compared with a predetermined vehicle front-rear direction acceleration DVSP (negative value). If dVSP ≤ DVSP, the process proceeds to step 83.
That is, by determining whether or not the vehicle is decelerating by a predetermined amount or more, it is determined whether or not the vehicle is traveling on an uphill with a predetermined gradient or more.

At step 83, the current throttle opening T
The VO and the QFLTTVO are compared. And TVO
If> QFLTTVO, it is determined that the vehicle is currently traveling on an uphill over a predetermined gradient (vehicle is decelerating), and the driver is depressing the accelerator to request acceleration, and at step 84, the curve traveling flag F is determined. Set ₂ to φ (non-curve running judgment). This routine is executed when the curve is determined in step 23, so the current vehicle traveling state is that the vehicle is traveling on a curve and the vehicle is decelerating.
Moreover, since the driver is requesting acceleration,
By setting the curve travel flag F ₂ to φ even during curve travel, the shift control (shift hold control) during curve travel is canceled, downshifting is permitted, and the driver's acceleration request is prioritized. This is to prevent the driver from feeling uncomfortable that the vehicle will not accelerate (or the vehicle speed will decrease) even when the driver steps on the accelerator, and suppresses the deterioration of vehicle drivability.

On the other hand, in step 82, it is determined that dVSP> DVSP.
If so, it is determined in step 83 that TVO ≦ QFLTTVO.
If yes, go to step 85 and
Gu F ₂Is set to 1 (curve traveling determination). That is,
If it does, the degree of deceleration of the vehicle (such as the grade) will be so large.
Because it is not difficult and there is no driver's strong acceleration demand,
And keeps track of the vehicle's running judgment, so that careless downshifting
To prevent the deterioration of vehicle stability due to the occurrence of
It In addition, in case of detecting the uphill condition by the slope (Fig. 10)
On the other hand, when detecting the vehicle acceleration directly,
The discomfort that occurs between the behavior and the behavior of the vehicle can be detected with higher accuracy.
It can be made easy to know. On the other hand, the slope is used to check the climbing condition.
When you go out, compared to when you detect the vehicle acceleration
Increases control response because it does not need to detect acceleration
be able to.

In this embodiment, the lateral acceleration G of the vehicle is
However, the lateral acceleration G may be detected by utilizing the rotational difference between the left and right driven wheels during cornering, as shown in FIG. . By the way, as in step 54 of FIG. 10 and step 83 of FIG. 13, if the value related to the driver's intention to accelerate is detected based on the value related to the throttle opening or the accelerator opening, Since the acceleration will be directly detected, the device can be made highly accurate and highly responsive. On the other hand, if the value related to the driver's intention to accelerate is detected based on the intake pressure as in step 74 of FIG. 12, the accuracy can be improved with a relatively simple configuration (a table or the like need not be provided). The driver's intention to accelerate can be detected well.

[0065]

As described above, according to the first aspect of the present invention, even when the vehicle is traveling on a curve, if the traveling resistance is equal to or more than a predetermined value, the gear speed maintenance by the curve-time gear speed retaining means is performed. Since the time control is released to allow kickdown etc., the vehicle running performance is improved and
It is possible to prevent the driver from feeling uncomfortable and unhappy that the vehicle does not move as intended.

According to the second aspect of the present invention, only when the running resistance exceeds a predetermined value while the vehicle is traveling on a curve and the driver intends to accelerate the vehicle, it is possible to maintain the gear speed by the curve gear speed holding means. Since the control is canceled, that is, the driver's intention to accelerate is confirmed and then the kickdown is allowed, the driver is not allowed to release the control for maintaining the shift speed during a curve more than necessary. While suppressing the occurrence of discomfort to the vehicle and the deterioration of vehicle stability during cornering, it improves the vehicle running performance when climbing uphill, etc., so that the driver does not feel discomfort that the vehicle does not move as intended. You can make it not feel.

According to the third aspect of the present invention, for example, even when the vehicle is traveling on a curve, when the vehicle is decelerating more than a predetermined amount, the control for maintaining the shift speed by the shift speed holding means for the bend is released. By allowing the kick down or the like, it is possible to improve the running performance of the vehicle and prevent the driver from feeling uncomfortable or unhappy that the vehicle does not move as intended.

According to the invention described in claim 4, only when the vehicle decelerates more than a predetermined amount while the vehicle is traveling on a curve and the driver intends to accelerate, the gear speed maintaining control by the curve gear speed maintaining means is performed. Is canceled, that is, after confirming the driver's willingness to accelerate, the kickdown etc. is permitted. While suppressing the occurrence of discomfort and the deterioration of vehicle stability during cornering, improve the vehicle running performance when climbing uphill, so that the driver does not feel discomfort that the vehicle does not move as intended. You can

According to the fifth aspect of the present invention, since the value related to the running resistance of the vehicle is configured as the value related to the slope of the road surface or the slope resistance, the uphill running state of the vehicle is detected with high accuracy. Therefore, the control accuracy of the device can be improved. According to the invention of claim 6, the second predetermined value is set depending on the rotational speed of the engine coupled to the automatic transmission.
The acceleration intention can be detected with higher accuracy.

[Brief description of drawings]

FIG. 1 is a block diagram of the invention according to claim 1.

FIG. 2 is a block diagram of the invention according to claim 2.

FIG. 3 is a block diagram of the invention according to claim 3.

FIG. 4 is a block diagram of the invention according to claim 4;

FIG. 5 is a system configuration diagram of an automatic transmission according to an embodiment of the present invention.

FIG. 6 is a flowchart showing shift control in the embodiment.

FIG. 7 is a flowchart showing shift control in the embodiment.

FIG. 8 is a flowchart showing shift control in the embodiment.

FIG. 9 is a flowchart showing shift control in the embodiment.

FIG. 10 is a flowchart showing a curve traveling determination flag setting control in the embodiment.

FIG. 11 is a flowchart showing a routine for calculating a gradient in the above embodiment.

FIG. 12 is a flowchart showing another curve running determination flag setting control in the embodiment.

FIG. 13 is a flowchart showing another curve running determination flag setting control in the embodiment.

FIG. 14 is a diagram for explaining an example of detecting lateral acceleration according to the embodiment.

FIG. 15 is a diagram for explaining a problem of shift control on a conventional curved road.

[Explanation of symbols]

 1 Engine 2 Automatic Transmission 3 Fluid Torque Converter 4 Gear Transmission 5 Hydraulic Actuator 6 Automatic Transmission Control Unit 7 Throttle Valve 8 Throttle Sensor 9 Vehicle Speed Sensor 10 Brake Switch 11 Lateral G Sensor

Claims (6)

[Claims] 1. A curve traveling detecting means for detecting a curve traveling state of a vehicle, and a curve-time shift forcibly holding a shift stage while the curve traveling state of the vehicle is detected. A gear holding means, a running resistance detecting means for detecting a value relating to a running resistance of the vehicle, and a running resistance detected by the running resistance detecting means while the gear is held by the curve gear holding means. A first speed-gear holding canceling means for canceling the holding of the speed-gear by the curve speed-gear holding means when the value related to the resistance becomes equal to or higher than a first predetermined value. And a shift control device for an automatic transmission. 2. A curve traveling detection means for detecting a curve traveling state of a vehicle, and a curve-time shift forcibly holding a shift stage while the curve traveling state of the vehicle is detected. A gear holding means, a running resistance detecting means for detecting a value related to the running resistance of the vehicle, an acceleration intention detecting means for detecting a value related to the driver's intention to accelerate, and When the value related to the running resistance detected by the running resistance detecting means becomes equal to or more than the first predetermined value while the value is held, the value detected by the acceleration intention detecting means is the second predetermined value. A gear shift control device for an automatic transmission, comprising: a second gear speed holding release means for releasing the holding of the gear speed by the curve gear speed holding means when the value is equal to or more than a value. 3. A curve traveling detecting means for detecting a curve traveling state of a vehicle, and a curve-time shift forcibly holding a shift speed while the curve traveling state of the vehicle is detected. The gear holding means, the acceleration detecting means for detecting the longitudinal acceleration of the vehicle, the acceleration intention detecting means for detecting a value related to the driver's acceleration intention, and the gear shift speed holding means for holding the shift speed. In the meantime, when the vehicle longitudinal acceleration detected by the acceleration detecting means becomes equal to or less than the third predetermined value, the third speed-gear holding canceling means cancels the holding of the speed-gear by the curve-gear speed-gear holding means. And a shift control device for an automatic transmission, comprising: 4. A curve traveling detecting means for detecting a curve traveling state of a vehicle, and a curve-time shift forcibly holding a shift stage while the curve traveling state of the vehicle is detected by the curve traveling detecting means. The gear holding means, the acceleration detecting means for detecting the longitudinal acceleration of the vehicle, the acceleration intention detecting means for detecting a value related to the driver's acceleration intention, and the gear shift speed holding means for holding the shift speed. While the vehicle is moving forward and backward, the acceleration in the vehicle front-rear direction detected by the acceleration detecting means becomes equal to or lower than a third predetermined value, and the value detected by the acceleration intention detecting means is equal to or higher than the second predetermined value. A shift control device for an automatic transmission, comprising: a fourth shift speed holding release means for releasing the holding of the shift speed by the shift speed holding means during a curve. 5. The shift control device for an automatic transmission according to claim 1, wherein the value related to the running resistance of the vehicle is a value related to a road slope or a slope resistance. . 6. The gear shift of the automatic transmission according to claim 2, wherein the second predetermined value is set depending on a rotation speed of an engine connected to the automatic transmission. Control device.