JPH03149463A - Controller for automatic transmission of car provided with traction controller - Google Patents

Abstract

PURPOSE:To prevent the expansion of the slipping of a drive wheel related to the shift of an automatic change gear by limiting a gear width at a time of the automatic transmission, to one gear stage, during the repression of driving force by a traction controller. CONSTITUTION:When the generation of the slip of a drive wheel is detected at the time of acceleration by an accelerating operational member, driving force is repressed by a traction controller so as to prevent the slip. During the repression of driving force by the traction controller, a gear width at a time of an automatic transmission by an automatic transmission control means is limited to one gear stage by a gear width limiting means. Drastic change in the driving force due to the change in a change gear ratio is not generated at the time of traction control, and the expansion of the slip of the drive wheel related to the shit of the automatic transmission can be prevented thereby.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an automatic transmission control device for automatically changing the gear stage of an automatic transmission in relation to the driving condition of the vehicle in a vehicle equipped with a traction control device. It is.

2. Description of the Related Art A gear stage of an automatic transmission is selectively set to one of a plurality of gear stages based on a pre-stored shift diagram in relation to the actual vehicle running condition, such as the throttle valve opening of the vehicle and the vehicle speed. An automatic transmission control device that switches to Vehicles equipped with such an automatic transmission control device may be provided with a so-called traction control device that prevents the drive wheels from slipping during acceleration operations. For example, the vehicle described in Japanese Unexamined Patent Publication No. 62-231836 is one example.

Problems to be Solved by the Invention However, in the above-mentioned conventional automatic transmission control device, when the driving force is suppressed by the traction control device in order to prevent acceleration slip of the driving wheels, the transmission ratio of the automatic transmission is It is configured to be maintained or increased, and eliminates problems such as a decrease in braking force due to a decrease in engine speed due to a shift up during traction control, and a decrease in driving force responsiveness. It looks like this.

However, as described above, if the automatic transmission is configured to increase the gear ratio during traction control, if the gear ratio is suddenly increased due to a significant downshift, the driving force generated by the throttle valve Regardless of the control, sudden changes in the driving force occur due to insufficient responsiveness of the driving force control. For this reason, there is an inconvenience in that the slip of the drive wheels increases in connection with downshifting of the automatic transmission even though control is being performed to suppress slip.

The present invention has been made against the background of the above circumstances,
An object of the present invention is to provide an automatic transmission control device that prevents drive wheels from slipping due to shifting during traction control.

Means for Solving the Problems The gist of the present invention to achieve the object is, as shown in the claim correspondence diagram of FIG. In such a case, in a vehicle equipped with a traction control device that suppresses the driving force to prevent such slippage, the gear shift control means automatically changes the gear stage of the automatic transmission in relation to the driving state of the vehicle. The automatic transmission control device includes a shift width limiting means for limiting one shift width of the automatic transmission to one gear stage while the traction control device is suppressing the driving force.

Function and Effect of the Invention In this way, in the shift width limiting means, one shift width of the automatic transmission is limited to one gear stage while the traction control device is suppressing the driving force. Therefore, during traction control, sudden changes in driving force due to changes in the gear ratio do not occur, which prevents the expansion of drive wheel slip related to automatic transmission shifts. .

EXAMPLE Hereinafter, an example of the present invention will be described in detail based on the drawings.

In FIG. 2, the output of an engine 1G is transmitted to drive wheels (rear wheels) 1B via a torque converter 12, a planetary gear type stepped transmission 14, and a differential gear device 16. The intake pipe 20 of the engine 10 includes a first throttle valve 24 that is connected to an accelerator pedal 22 and rotated to an opening degree corresponding to the amount of pedal depression, and a throttle actuator 26 that includes a step motor or the like.
A second throttle valve 28, which is rotated by the throttle valve 28, is arranged in series. The opening degree θ of the first throttle valve 24 and the opening degree θ3 of the second throttle valve 28 are detected by the main throttle opening sensor 30 and the sub-throttle opening sensor 32.
, and θ3 are generated by the combustion control electronic control unit (
(hereinafter referred to as BFt ECU) 34 and a traction control electronic control unit (hereinafter referred to as TRCECU) 36
It is designed to be supplied to each.

The rotational speeds of the pair of front wheels 38 of the vehicle are detected by a pair of front wheel speed sensors 40, and signals representing these rotational speeds are supplied to the TRCECU 36. Further, the rotational speed N1 of the engine 10 is determined by the engine rotational speed sensor 44.
The signal representing the engine rotational speed Nt is detected by the TRCECU 36 and the automatic transmission control electronic control unit (hereinafter referred to as ECTECU).
46. Further, the output shaft rotation speed Nout of the stepped transmission 14 (that is, the rotation speed of the rear wheels 18) is detected by the vehicle speed sensor 48, and the output shaft rotation speed N is detected by the vehicle speed sensor 48. The signal representing U7 is TRCECU36
and is supplied to the ECTECU 46. Further, a shift position sensor 42 for detecting an actual shift position is provided in the stepped transmission 14, and a signal representing the actual gear position is supplied to the ECTECU 46.

The above EFIECU34, TRCECU36, and EC
The TECU 46 is each composed of a so-called microcomputer including a CPU, RAM, and ROM.
The CPU processes input signals according to a program stored in advance in the ROM while utilizing the storage function of the RAM, and outputs a predetermined output.

For example, the EF IECU 34 determines the basic injection time based on the actual engine speed N1 and intake air amount or intake pipe negative pressure from a pre-stored relationship,
A correction based on the magnitude and rate of change of the throttle opening θ4 is added to this basic injection time, and a drive signal for opening the fuel injection valve 50 at the corrected injection time is output. In addition, when the throttle opening θH becomes the minimum when the vehicle speed is higher than a predetermined speed, the fuel injection valve 5 is
A drive signal for closing 0 is output. Additionally, in the event that slip occurs in the drive wheels 18 during a start acceleration operation, in order to suppress the rotational torque of the drive wheels 18,
A signal for retarding the ignition timing of the spark plug 52 and a drive signal for closing the fuel injection valve 50 are output. In addition, the EFIECU 34 determines the smaller of the opening θ of the first throttle valve 24 and the opening θ of the second throttle valve 28, and sends a signal representing the smaller opening to the ECTECυ 46. Supplied.

Further, for example, in the TRCECU 36, the slip rate S of the rear wheels 18 is determined from the rotational speed difference between the rear wheels 18 and the front wheels 38, and the slip rate S is calculated based on the driving force and lateral resistance of the rear wheels 18 during acceleration operation of the vehicle. A drive signal for driving the throttle actuator 26 is outputted, and a signal for requesting a retard angle and a fuel cut is outputted to the EFIECU 34 so that both are within the obtained range.

Further, in the ECTECU 46, a shift diagram corresponding to the actual gear is determined from a plurality of types of shift diagrams stored in advance for each gear, and from the shift diagram, the first throttle valve 2
4 and the opening θ8 of the second throttle valve 28, whichever is smaller, and the traveling speed, the shift up or down is determined, and the shift signal for changing the gear is stepped. It is supplied to the solenoid valve of the transmission 14 and also to the TRCECU 36.

Note that when the torque control i11 (TRCi control) is not in progress, the opening degree θ of the second throttle valve 2B.

is kept fully open. Furthermore, while the shift prohibition request signal is being supplied from the TRCECU 36, the output of the shift signal for switching gears is stopped.

Figure 1 shows the above EF IECU34 and TRCECU36.
, is a block diagram illustrating the functions of the ECTECU 46. In the throttle opening degree switching means 60, the throttle opening degree used for automatic shift control is switched to the smaller of the opening degree θ of the first throttle valve 24 and the opening degree θ3 of the second throttle valve 28. . The shift position calculating means 62 determines the shift position W (for example, target gear) based on the throttle valve opening degree and traveling speed (output shaft rotational speed N1) U7) which have been switched from the shift diagram stored in advance. Ru. Then, in the shift position control means 64,
A shift signal is output to the stepped transmission 14 so that the above shift position matches the actual shift position detected by the shift position sensor 42 functioning as a shift position detection means.

On the other hand, the acceleration slip detection means 66 detects the driven wheel speed detected by the front wheel speed sensor 40 and the vehicle speed sensor 4.
The slip ratio S is determined from the rotational speed difference with the driving wheel speed detected by 8, and the throttle actuator 26 is driven so that the slip ratio S is within a predetermined range in which both the driving force and the lateral drag force are compatible. Ru. This throttle actuator 26 functions as a throttle control means. When a signal indicating that an acceleration slip is in progress is supplied from the acceleration slip detection means 66 to the shift prohibition command means 68, a shift prohibition request signal is issued that requests the prohibition of gear change only during the period in which the acceleration slip is in progress. It is supplied from the prohibition command means 68 to the shift position control means 64. On the other hand,
The road surface μ estimation calculation means 70 calculates the friction coefficient μ of the running road surface based on the driven wheel speed, and the shift position calculation means 72 according to the road surface μ calculates the friction coefficient μ of the actual traveling road surface. and the gear shift position l according to its friction coefficient μ based on the actual gear stage! (gear stage) is determined. Then, the shift position change timing determining means 74 determines the gear change timing, and a shift prohibition request signal is supplied to the shift prohibition command means 68 so that the gear change is performed at that time. As a result, the gear shift is performed at a gear shift timing that achieves both suppression of acceleration slip and acceleration performance of the vehicle.

Below, the EFIECU34, TRCECU36, EC
The main parts of the control operation of TECυ46 are shown in Figures 3, 4, and 5.
This will be explained using the diagram and the flowchart of FIG.

FIG. 3 shows a shift prohibition request routine in the TRCECU 36. In the figure, in step 100, the drive wheels 1B
It is determined whether or not TRC control is being performed to control the drive torque of the vehicle. If it is determined in step 100 that TRC control is not in progress, in step 210
The content of the TRC signal output to indicate that the control is in progress is O.
FF, and in step 220, the EC
The content of the SHIFT permission signal outputted to perform a shift to the shift position determined by the TECU 46 is turned ON.

This St(IFT permission signal) is a signal that allows the ECTECU 46 to control the gear change of the stepped transmission 14, that is, it permits the operation to change the gear position of the stepped transmission 14, and its content is OFF. At one time, a shift prohibition request is issued from the TRCECU 36 to the ECTECU 46.

However, if it is determined in step 100 that the TRC control is in progress, then in step 110 the TR
As the content of the C signal is turned ON, step 120
In step SHI FT, it is determined whether the content of the SHI FT permission signal is OFF. In step 120 SHIFT
If it is determined that the content of the permission signal is not OFF,
In step 130, TR is also used in the previous cycle.
It is determined whether or not C control is in progress, and Stain 7
In step 140, it is determined whether or not the shift position of the stepped transmission 1114 has changed.If it is determined in step 130 that TRC control was not in progress in the previous cycle, or the determination in step 13G and step 140 If both are affirmed, step 1
At step 50, the content of the SHIFT permission signal is turned OFF and a shift prohibition request state is entered. However, even if the determination at step 130 is affirmative, it is determined at step 140 that the shift position of the stepped transmission 14 has not changed. If so, this routine is terminated.

If it is determined in step 120 that the content of the SHIFT permission signal is OFF, steps 160 and subsequent steps are executed to issue permission for shifting. First of all,
In step 160, it is determined whether the OFF state of the SHIFT permission signal continues for one second or more, and the stetener 170 determines the average value Δv0 of the slip amount.
It is determined whether or not it is less than a predetermined value, for example, 2 kg*/h. This average value ΔV awe of the amount of slip is repeatedly calculated at a constant short cycle by, for example, an interrupt routine shown in FIG. That is, in FIG. 4, in step 300, the slip amount ΔV is calculated based on the rotation of the driven wheels 38 (by subtracting the control target vehicle speed V, which is the vehicle speed plus the target slip amount, from the drive wheel vehicle speed V, In step 31O, the slip amount ΔV calculated in each cycle is sequentially added, and in step 320, "l" is added to the contents of the counter CN for calculating the average value.Then, in step 330, the contents of the counter CN are added. It is determined whether or not N has reached a predetermined constant value N. If it is determined that N has not been reached, this interrupt routine is terminated, but if it is determined that N has been reached, step At 340, the average value ΔV of the slip amount is calculated by dividing the added value of the average values up to that point by the number of additions N.
, , are calculated, the addition contents are cleared to [0] in step 350, and the contents of the counter CN are cleared to [0] in step 360.

Returning to FIG. 3, it is determined in step 160 that the OFF state of the SRIFT permission signal does not continue for more than 1 second, or it is determined in step 170 that the average slip amount ΔV awe is not less than 21 am/h. In this case, this routine is terminated. However, if both of the judgments in steps 160 and 170 are affirmative, in step 180, the actual shift position and the driven wheel speed are determined from the pre-stored relationship. Based on the estimated road surface frictional resistance value p calculated from the differential value, the speed change judgment vehicle speed K V r at which the speed change should be performed is determined. The above relationship is such that the smaller the estimated road friction resistance value p, the lower the gear shift judgment vehicle speed K.
This was determined in advance to increase driving stability by reducing V and suppressing gear changes on roads with low μ. Then, in step 190, the drive wheel vehicle speed V
It is determined whether or not , has become equal to or higher than the speed change judgment vehicle speed KV. The drive wheel vehicle speed vF is the shift judgment vehicle speed KV.

If the drive shaft vehicle speed vF is still smaller than the shift judgment vehicle speed KV, this routine is terminated.

When it is determined that S has been reached, in step 200 S
) I I The FT permission signal is turned on.

That is, by executing the routine shown in FIG. 3 in the TRCECU 36, when TRCljllll is not in progress, T
The contents of the RC signal are turned OFF and S) IIFT
The permission signal is in the ON state, and normal gear shift control is switched to ECTE.
It is now executed by the CU 46. However, T.R.C.
The shift prohibition request continues until the slip of the driving wheels 18 becomes small and the vehicle speed exceeds a predetermined value KV after the start of @@ or the execution of the shift, and the ECTECU 46 does not execute the shift.

FIG. 5 shows the speed change control routine of the ECTECU 46. In the figure, in step 400, a target shift position (target gear position) g is determined based on the actual vehicle speed V and throttle valve opening θ from a previously stored shift diagram
is determined. The above throttle valve opening θ is EF I
It is determined by the throttle opening degree selection routine shown in FIG. 6 executed by the ECU 34. That is, in the STEM PRO 00 of FIG. 6, it is determined whether the opening degree θ of the first throttle valve 24 is smaller than the opening degree θ3 of the second throttle valve 28, and if it is determined that it is smaller, In step 610, the first throttle valve 24 is set in the register TA.
The opening degree θ7 of the second throttle valve 28 is stored, but if it is determined to be large, the opening degree θ of the second throttle valve 28 is stored in the register TA in step 620. That is, the opening degree θa of the first throttle valve 24 and the second throttle valve 28
The throttle valve opening θ, whichever is smaller, is selected. Then, in step 630, the contents of the register TA are converted into a communication code signal, and
In step 640, the communication code signal is EF I E
It is output from the CU 34 to the ECTECU 46. As a result, the throttle valve opening degree θ used when the target gear stage g is determined in step 400 of the ECTECU 46
Therefore, the smaller of the opening degree θ of the first throttle valve 24 and the opening degree θ3 of the second throttle valve 28 is used.

Returning to FIG. 5, in step 410, TRCECU3
It is determined whether the TRC signal supplied from 6 is in the OFF state, in other words, whether or not the TRCECU 36 is under acceleration slip control.

If it is determined that acceleration slip control is not in progress, normal shift control is executed. That is, first step 430
It is determined whether the target shift position gt matches the actual shift position Wig or not. If it is determined that they match, this routine is terminated, but if it is determined that they do not match, then In step 2440, it is determined whether or not to shift up. If it is determined to be a shift up, shift up control is executed in step 450, and if it is determined to be a downshift, shift down control is executed in step 460, so that the target shift position gt and the actual shift position g match. I am made to do so. In this case, the target shift position g1 and the actual shift position g
Even if there is a difference of two gears or more, the actual shift position Kg is directly brought into agreement with the target shift position gL.

However, if it is determined in step 410 that the TRCECU 36 is under acceleration slip control, it is determined in step 420 whether the content of the SHIFT permission signal from the TRCECU 36 is in the ON state. In step 420, the content of the SHIFT permission signal is ON.
If it is determined that the SHIFT permission signal is not in the ON state, this routine is terminated because the shift prohibition request state is in effect. However, if it is determined that the content of the SHIFT permission signal is in the ON state,
Since the shift is permitted, one gear shift is executed. That is, in step 470, it is determined whether or not the target shift position g1 matches the actual shift position g. If it is determined that they match, this routine is terminated, but if it is determined that they do not match, the routine is terminated. In the event that
In step 480, it is determined whether to shift up.

If it is determined that the shift is up, the content of the target shift position gt is changed to the actual shift position g in step 490.
After the target shift position If g t (=
Shift-up control is performed so that g +1 ) and the actual shift position g match.

However, if it is determined in step 480 that it is not an upshift, the contents of the target shift position gt are updated to a position (g-l) one step lower than the actual shift position g in step 510, and then in step 520 Downshift control is performed so that the target shift position gt (=g-1) and the actual wrinkle shift position g match. In this case, the target shift position gt and the actual shift position tg
Even if there is a difference of two or more gears, only one gear will be changed in one control cycle.

In a state where the above operations are repeatedly performed, ECT
In the ECU 46, ・TRCt control is in progress and S
When the HIFT permission signal is in the ON state, by executing steps 470 to 520 corresponding to the change width limiting means, the gear position of the stepped transmission 4 is limited to one gear at a time, so that the change range is significantly reduced. No significant change in gear ratio occurs.

Therefore, during TRC control, a sudden change in the driving force due to a change in the gear ratio does not occur, so that the slip of the drive wheels 18 associated with the shift of the stepped transmission 14 is prevented from increasing. For example, when traction control is started during start acceleration in 1st gear, the ECTECU4
6, the second throttle valve 28 has a smaller opening degree.
When a shift is determined based on the opening degree θ, a large upshift is determined because the opening degree θ8 is extremely small in order to control the driving force. Since it is limited to one gear at a time, the rapid drop in driving force caused by a large upshift is eliminated. Further, according to this embodiment, while traveling at a predetermined speed, as in the conventional method, downshifting is performed to increase the gear ratio of the automatic transmission 14 during traction control to prevent slippage of the drive wheels. In this system, even if a significant downshift is determined, the downshift is limited to one step at a time, so slippage of the drive wheels accompanying the downshift is suppressed.

FIG. 7 is a time chart of the control operation of the above-described embodiment. In the figure, slip occurs in the driving wheels 18 while driving in the first gear, and TRC control is started to suppress the slip, so that the throttle opening θ of the second throttle valve 28 is closed. However, since one gear change is suppressed to 1st gear by the control of the ECTECU 46, there is no sudden change in the gear ratio of the stepped transmission 14, and the difference between the driving wheel speed vF and the driven wheel speed is The amount of slip appearing in the difference is relatively small and the time width is short. Moreover, since the width of each change in the gear ratio is small, the driving force does not increase as much.

On the other hand, in the conventional device, as shown in FIG. 8, during the T RC1111110 period during which the car is running in the first gear, the gear shifts to the third gear and then to the fourth gear. Since it is shifted up, the stepped transmission 14
The gear ratio suddenly increased, and as shown by the difference between the driving wheel speed vF and the driven wheel speed at that time, a relatively large and long-duration slip occurred. Also, the...
There was an inconvenience that the sudden increase in the gear ratio caused the drive to become strained.

Although one embodiment of the present invention has been described above based on the drawings,
The invention also applies in other aspects.

For example, in the above-mentioned embodiment, each shift is suppressed to one gear during upshifting and downshifting during TRC control, but even if the shift is suppressed only during upshifting or downshifting. A certain effect can be obtained.

Moreover, in the above-mentioned embodiment, BF I ECU34, T
Although the RCECU 36 and the ECTECυ 46 are configured by independent computers, they may be configured integrally by a common microcomputer.

It should be noted that the above-mentioned example is just one embodiment of the present invention, and various modifications may be made to the present invention without departing from the spirit thereof.

[Brief explanation of the drawing]

FIG. 1 is a block diagram illustrating the functions of the control device of the embodiment shown in FIG. FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention. FIG. 3 is a flowchart illustrating the main part of the operation of the TRCECU in the embodiment of FIG. 2. FIG. 4 is a flowchart illustrating the operation of the interrupt routine executed in the TRCECU. FIG. 5 shows the ECTE in the embodiment of FIG.
3 is a flowchart illustrating a main part of the operation of the CU. FIG. 6 is a flowchart illustrating the main part of the operation of the EFIECU in the embodiment shown in FIG. Figure 7 shows the second
3 is a time chart illustrating the operation of the illustrated embodiment. FIG. 8 is a time chart illustrating the operation of the conventional device. FIG. 9 is a diagram corresponding to claims of the present invention. 34: EFIECU 36: TRCECU (Traction control unit) 46
: ECTECU (speed change control means) Step 4 flow to 520: Shift width limiting means 2 a1 j 1 Yesterday Mi 3 pull 1 Figure 4 la-V=Vi-Vr 1 1ΣΔ■-ΣΔ■+Δvl lcN=cN+1 1 13 Father, 1 1 3so-,. 1 11cN-01 Figure 6 lTA=θMl l TA=θsl 沁 1 1Tsunshu I Corsho No. B History 1 11F Figure l Interval Figure 8 1y l j -1゜ru 1 - " l Figure 9

Claims (1)

[Claims] In a vehicle equipped with a traction control device that suppresses the driving force to prevent the slippage of the drive wheels when the drive wheels slip when accelerated by the acceleration operation member,
An automatic transmission control device that automatically switches a gear stage of an automatic transmission in relation to a running state of the vehicle by a transmission control means, wherein during driving force suppression by the traction control device, one of the gears of the automatic transmission 1. An automatic shift control device for a vehicle equipped with a traction control device, characterized in that the device includes a shift width limiting means for limiting the shift width at one time to one gear stage.