JP2946774B2 - Traction control device for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traction control device for a vehicle which optimally controls traction acting on a drive wheel when a drive wheel slip occurs by controlling opening and closing of a throttle valve.

[0002]

2. Description of the Related Art Conventionally, as a traction control device for a vehicle, for example, a device described in JP-A-62-45944 is known.

In this conventional source, a second throttle valve, which can be opened and closed from the outside, is provided in series with an intake passage of an engine in addition to a first throttle valve interlocked with an accelerator operation, and when a throttle control condition is satisfied, that is, When the driving wheel slip exceeds the throttle control threshold value, the second throttle valve is opened, closed, and held in three modes according to the driving wheel slip occurrence state, and the engine output is controlled to be reduced. A technique for suppressing wheel slip is disclosed.

[0004]

However, in such a conventional vehicle throttle control device, the throttle closing speed is kept constant when the throttle valve is closed in the throttle control for suppressing the driving wheel slip. When the throttle valve is opened, the throttle opening speed is set lower as the deviation between the driving wheel speed and the driven wheel speed is larger, and control is performed to compensate for the delay in the rise of the output torque of the engine. Therefore, as shown in FIG. The hunting of the control occurs on the friction coefficient road due to the high throttle valve opening speed, and the convergence and stability of the drive wheel slip deteriorate. On the road with a high friction coefficient, the first throttle valve linked with the accelerator operation is not effective immediately after the closing speed of the throttle valve is high and the throttle control is started, so that the accelerator control region of the driver is narrow and the acceleration is impaired.

That is, since the opening / closing speed of the throttle valve is not set by taking in the road surface friction coefficient information or turning state information, fine control cannot be performed based on the road surface friction coefficient or turning state. Not suitable for sporty running in

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. In a traction control device for a vehicle by controlling opening and closing of a throttle valve, the convergence and stability of a drive wheel slip when traveling on a road with a low coefficient of friction. The objective is to increase the accelerator control area of the driver when traveling on a road with a high coefficient of friction to ensure acceleration.

[0007]

In order to solve the above problems, a traction control device for a vehicle according to the present invention incorporates road surface friction coefficient information and turning state information by detecting lateral acceleration and longitudinal acceleration to form a road with a low friction coefficient. When it is determined that the road is high, the closing speed of the throttle valve is made high and the opening speed is made low, and when it is determined that the road is of a high friction coefficient, the closing speed of the throttle valve is made low and the opening speed is made high.

That is, as shown in the claim correspondence diagram of FIG. 1, a valve actuator b for opening and closing the throttle valve a independently of the accelerator operation, and a drive wheel slip detecting means c for detecting a slip condition of the engine drive wheels.
A lateral acceleration detecting means d for detecting a vehicle lateral acceleration, a longitudinal acceleration detecting means e for detecting a vehicle longitudinal acceleration, and a throttle closing speed setting means for setting a throttle closing speed to be lower as the lateral acceleration and the longitudinal acceleration increase. f, throttle opening speed setting means g for setting the throttle opening speed to be higher as the lateral acceleration and the longitudinal acceleration increase,
When the detected drive wheel slip value is equal to or greater than a predetermined value, a control command for closing the throttle valve a is output to the valve actuator b according to the set throttle closing speed. Throttle control means h for outputting a control command for opening the throttle valve a to the valve actuator b according to the opening speed.

[0009]

When the vehicle is traveling straight or turning on a road with a low friction coefficient, the lateral acceleration detected by the lateral acceleration detecting means d and the longitudinal acceleration detected by the longitudinal acceleration detecting means e are small values. The closing speed setting means f sets a high throttle closing speed, and the throttle opening speed setting means g sets a low throttle opening speed. Accordingly, when the detected value of the drive wheel slip from the drive wheel slip detector c is equal to or greater than the predetermined value, the throttle control means h outputs a control command to close the throttle valve a to the valve actuator b at the set high throttle closing speed. When the detected value of the driving wheel slip from the driving wheel slip detecting means c becomes equal to or less than a predetermined value, the throttle valve a is set at the set low throttle opening speed.
Is output to the valve actuator b.

At the time of turning acceleration on a road with a high friction coefficient, the lateral acceleration detected by the lateral acceleration detecting means d and the longitudinal acceleration detected by the longitudinal acceleration detecting means e are large values. f, the throttle closing speed is set to a low speed, and the throttle opening speed setting means g
Is set to a high throttle opening speed. Accordingly, when the detected value of the drive wheel slip from the drive wheel slip detector c is equal to or greater than the predetermined value, a control command to close the throttle valve a at the set low throttle closing speed is output to the valve actuator b. When the detected value of the driving wheel slip from the driving wheel slip detecting means c becomes equal to or less than a predetermined value, a control command for opening the throttle valve a at the set high throttle opening speed is output to the valve actuator b.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration will be described. FIG. 2 is an overall view of a control system for a rear wheel drive vehicle to which the vehicle traction control device according to the embodiment of the present invention is applied. Throttle control for controlling a motor throttle opening degree so that a rear wheel slip ratio is within an optimum allowable range. The system is installed.

The control system includes an air flow meter AFM, an engine centralized electronic control unit ECCS C / U, and an injector as peripheral systems as shown in the figure.
An engine centralized electronic control system that centrally controls fuel injection control, ignition timing control, idle speed correction, etc., and an automatic transmission control unit A / TC / U and shift solenoid that perform shift control and lock-up control There is provided a transmission control system and a constant-speed cruise control system that has an ASCD actuator and performs automatic vehicle speed control so as to maintain a set vehicle speed.

[0013] As a control related to the traction control performed using the tandem throttle, in the engine centralized electronic control system or the automatic transmission control system, a traction switch signal TCS SW indicating whether or not the traction control is performed and a first traction switch signal TCS SW or the like. A throttle signal TVO1 or a second throttle signal TVO2 is input, and control (select low control) for selecting a smaller valve opening between the first throttle valve and the second throttle valve as throttle opening information during traction control is performed. In the constant speed traveling control system, a traction switch signal TCS SW or the like is input, and during traction control, control related to traction control such as prohibiting constant speed traveling control is performed.

Next, traction control (driving force reduction control) in the embodiment is performed by motor throttle opening control, and the electronic control is performed by a traction control system electronic control unit TCS-ECU (hereinafter, TCS-ECU). ).

The TCS-ECU includes a right front wheel speed V _ANR from the right front wheel speed sensor 1 and a left front wheel speed V _ANR from the left front wheel speed sensor 2.
_ANL , the right rear wheel speed V _NAR from the right rear wheel speed sensor 3, the left rear wheel speed V _NAL from the left rear wheel speed sensor 4, and the lateral acceleration sensor 5
(Corresponds to the lateral acceleration detection means) and the lateral acceleration Y _G and TCS
The switch signal SW _TC from the switch 6, the switch signal SW _ST from the brake lamp switch 7, and the throttle 1 actual opening DKV from the throttle control module TCM.
And longitudinal acceleration sensor 8 (corresponding to longitudinal acceleration detecting means)
The longitudinal acceleration _{XG and the} like from are input. And TCS-ECU
From the throttle control module TC to control the motor throttle opening when driving wheel slip occurs.
M (hereinafter abbreviated as TCM) with throttle 2 target opening DK
R is output.

Note that, in addition to the above output, the TCS-ECU
At the time of S failure, a lighting command is output to the TCS fail lamp 14, and at the time of TCS operation, a lighting command is output to the lamp 15 during TCS operation.

The TCM is a control circuit mainly including a throttle motor drive circuit. The TCM receives a first throttle signal TVO1 from the first throttle sensor 16 and outputs it to the TCS-ECU as a throttle 1 actual opening degree DKV. The second throttle signal TVO2 from the second throttle sensor 17 is applied to the throttle 2
And inputs the feedback information for the target opening DKR, applies the motor driving current I _M to the throttle motor 18 based on the throttle 2 target opening DKR from TCS-ECU (corresponding to the valve actuator).

Here, the first throttle valve 19 provided with the first throttle sensor 16 is connected to the accelerator pedal 2.
A second throttle valve 21 (corresponding to a throttle valve) provided with a second throttle sensor 17 is provided in the engine intake passage 22 in a series arrangement with the first throttle valve 19, The valve is opened and closed by a throttle motor 18.

The operation will be described.

FIG. 3 is a flowchart showing a throttle opening speed calculation routine performed by the TCS-ECU (corresponding to throttle opening speed setting means).

[0021] At step 30, the acceleration X _G and the lateral acceleration Y _G front and rear are input. In step 31, the opening speed set gain K _G1 is required to determine the throttle opening speed V _TO based on the longitudinal acceleration X _G. The opening speed setting gain K _G1, as shown in (b) of FIG. 4, the longitudinal acceleration X _G is a small constant value when: X _GL, the longitudinal acceleration X _G is longitudinal exceeds X _GL acceleration X _G It is set by a value that increases in proportion to the size. In step 32, it is determined whether the value of the lateral acceleration absolute value | Y _G | exceeds the low lateral acceleration set value Y _GL ,
When | Y _G |> Y _GL , the routine proceeds to step 33, where the throttle opening speed V _TO is obtained by the equation V _TO = K _G1 · | Y _G | + b. When | Y _G | ≦ Y _GL , the _routine proceeds to step 34, where the throttle opening speed V _TO is set to V _TO = V _TOMIN . In step 35, the throttle opening speed V _TO calculated in step 33 whether V _TO> V _TOMAX is determined, V _TO
If> V _TOMAX , step 36 sets V _TO = V _TOMAX . In step 37, the value obtained in step 33 or step 34 or 36 is set as the throttle opening speed _VTO . That is, the throttle opening speed V _TO, as shown in FIG. 4 (a) would be set to a high speed value larger the longitudinal acceleration X _G and the lateral acceleration Y _G.

FIG. 5 is a flowchart showing a throttle closing speed calculation routine performed by the TCS-ECU (corresponding to throttle closing speed setting means).

[0023] At step 50, the acceleration X _G and the lateral acceleration Y _G front and rear are input. In step 51, the closing speed setting gain K _G2 determine the throttle closing speed V _TC is determined based on the longitudinal acceleration X _G. The closing speed setting gain K _G2, as shown in FIG. 6 (b), and a large constant value when the longitudinal acceleration X _G is less than X _GL, the longitudinal acceleration X _G exceeds X _GL when longitudinal acceleration X _G is set by the magnitude lower becomes the value in proportion to, yet, is small constant value when the longitudinal acceleration X _G exceeds X _GH. In step 52, it is determined whether or not the value of the lateral acceleration absolute value | Y _G | exceeds the high lateral acceleration set value Y _GH . When | Y _G | ≦ Y _GH , the routine proceeds to step 53, where the throttle closing speed V _TC Is obtained by the equation of V _TC = K _G2 · | Y _G | + c. When | Y _G |> Y _GH , the routine proceeds to step 54, where the throttle closing speed V _TC is set to V _TC = V _TCMIN . In Step 55, Step 53 or Step 5
The value obtained in 4 is set as a throttle closing speed V _TC. That is, the throttle closing speed V _TC, as shown in FIG. 6 (a) would be set to a low speed value larger the longitudinal acceleration X _G and the lateral acceleration Y _G.

FIG. 7 is a flowchart showing the flow of the motor throttle opening control operation performed by the TCS-ECU (corresponding to throttle control means).

In step 70, each wheel speed sensor 1,
From 2, 3, 4 to right front wheel speed V _ANR , left front wheel speed V _ANL , right rear wheel speed
V _NAR and left rear wheel speed V _NAL are read. In step 71, the vehicle speed is calculated based on the average value of the right front wheel speed V _ANR and the left front wheel speed V _ANL.
V _MNA is calculated. In step 72, the average driving wheel speed V _MAN is calculated from the average value of the right rear wheel speed V _NAR and the left rear wheel speed V _NAL . In step 73, the average driving wheel speed V _MAN and the vehicle speed V
Front and rear wheel average speed [Delta] V _A is calculated by the difference between _MNA (corresponding to the drive slip detection means). In step 74, the throttle control slip ratio S _S is calculated from the average driving wheel speed V _MAN and the vehicle speed V _MNA (corresponding to a driving slip detecting means). In step 75, the vehicle speed determined by the calculation
V _MNA , front and rear wheel average speed ΔV _A , throttle control slip ratio
And S _S, compared with the preset throttle control threshold map shown in step 76 is performed. Step 77
Then, it is determined whether the comparison result in step 75 is the throttle opening throttle holding or the throttle closing. When the result of determination that the throttle opening, the process proceeds to step 78, the throttle opening speed V _TO set in the routine of FIG. 3 is read, the second throttle valve 21 at the throttle in step 79 opening speed V _TO An open command is output. If the result is that the throttle is held,
Proceeding to step 80, a command for maintaining the valve opening of the second throttle valve 21 is output. If the result of determination that the throttle closed, the process proceeds to step 81, the throttle shutting speed V _TC that was set in the routine of FIG. 5 is read, the second throttle valve 21 at step 82 in the throttle closing speed V _TC Close command Is output.

Next, the operation will be described separately for traveling on a road with a low friction coefficient and traveling on a road with a high friction coefficient.

(A) When traveling on a road with a low friction coefficient When traveling straight or turning on a road with a low friction coefficient, FIG.
As shown in, for a longitudinal acceleration X _G is small value detected by the lateral acceleration Y _G also longitudinal acceleration sensor 8 are detected by the lateral acceleration sensor 5, a high speed of the throttle closed in the throttle closing speed calculation routine in FIG. 5 is set to a speed V _TC, it is set to the low speed of the throttle opening speed V _tO in the throttle opening speed calculation routine in FIG. Accordingly, the throttle control routine of FIG. 7, when the throttle control slip ratio S _S exceeds 4%, the control command for closing the second throttle valve 21 is output to the throttle motor 18 by a high speed of the throttle closing speed V _TC that was set control command to open the second throttle valve 21 by the set slow throttle opening speed V _tO When throttle control slip ratio S _S is equal to or less than 2% is output to the throttle motor 18. As a result, in the low friction coefficient road, as shown in FIG. 8, a throttle closing speed V _TC of the second throttle valve 21
Is high and the throttle opening speed _VTO is low, whereby a sufficient reduction in engine torque is achieved, and high convergence and stability of the drive wheel slip are achieved.

(B) When traveling on a road with a high coefficient of friction At the time of turning acceleration on a road with a high coefficient of friction, the lateral acceleration sensor 5
Lateral acceleration detected by Y for _G also longitudinal acceleration X _G also large value detected by the acceleration sensor 8 before and after, is set to the low speed of the throttle closing speed V _TC in the throttle closing speed calculation routine in FIG. 5, FIG. 3 It is set to fast throttle opening speed V _tO in the throttle opening speed calculation routine. Accordingly, the throttle control routine of FIG. 7, when the throttle control slip ratio S _S exceeds 4%, the first by slow throttle closing speed V _TC that was set 2
A control command to close the throttle valve 21 is output to the throttle motor 18, and the throttle control slip ratio _SS becomes 2
%, The set high throttle opening speed V
_A control command for opening the second throttle valve 21 is output to the throttle motor 18 by _TO . As a result, during turning acceleration on a road with a high friction coefficient, the second throttle valve 2
By first throttle closing speed V _TC is low, to the effect of the first throttle valve 19 is secured a drive-wheel slip is to work with even while the accelerator operation enters the throttle control is generated, also, the drive wheels When the slip has converged, the throttle opening speed _VTO is high, so that the first throttle valve 1 has good response from the convergence of the drive wheel slip.
As a result, the effect of No. 9 is ensured, the accelerator control area of the driver is expanded, and the acceleration is not impaired.

[0029] As described above, in the embodiment, in the vehicle traction control apparatus according to opening and closing control of the throttle valve, detecting a turning state information road surface friction coefficient information of the lateral acceleration Y _G and longitudinal acceleration X _G By
When it is determined that the road has a low friction coefficient, the throttle closing speed V
Fast to the throttle opening speed V _TO the _TC at low speed, since the time of determination that the high friction coefficient road where the apparatus for high speed throttle opening speed V _{T O} to slow the throttle closing speed V _TC,
When traveling on a road with a low friction coefficient, convergence and stability of the drive wheel slip can be achieved, and when traveling on a road with a high friction coefficient, the accelerator control area of the driver can be expanded to ensure acceleration.

That is, since the opening / closing speed of the throttle valve is set by taking in the road surface friction coefficient information and the turning state information, fine control based on the road surface friction coefficient and the turning state is performed. It is effective for

Although the embodiment has been described with reference to the drawings, the specific configuration is not limited to this embodiment. For example, in the embodiment, the example in which the throttle control is performed by the second throttle valve of the tandem throttle has been described. However, the present invention can be applied to a throttle control system using one throttle valve that can be controlled to be opened and closed by an actuator in conjunction with an accelerator padal. . Further, in the embodiment, the example of the traction control device using only the throttle control is shown. However, the present invention can be applied to a system using both the brake control and the throttle control.

[0032]

As described above, according to the present invention, in a traction control device for a vehicle based on opening / closing control of a throttle valve, road surface friction coefficient information and turning state information are acquired by detecting lateral acceleration and longitudinal acceleration. A means for increasing the closing speed of the throttle valve to a high speed and decreasing the opening speed to a low speed when it is determined that the road is a low friction coefficient road, and a means for decreasing the closing speed of the throttle valve to a low speed and increasing the opening speed when it is determined to be a high friction road. As a result, when driving on a low friction coefficient road, the convergence and stability of the drive wheel slip can be improved, and when driving on a high friction coefficient road, the accelerator control area of the driver can be expanded to ensure acceleration. The effect is obtained.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims showing a traction control device for a vehicle according to the present invention.

FIG. 2 is an overall control system of a rear-wheel drive vehicle to which the vehicle traction control device of the embodiment is applied.

FIG. 3 is a flowchart showing a throttle opening speed calculation routine performed by an electronic control unit of the traction control system of the embodiment.

FIG. 4 (a) is a throttle opening speed characteristic diagram, and FIG. 4 (b) is an opening speed setting gain characteristic diagram.

FIG. 5 is a flowchart showing a throttle closing speed calculation routine performed by an electronic control unit of the traction control system of the embodiment.

6A is a throttle closing speed characteristic diagram, and FIG. 6B is a closing speed setting gain characteristic diagram.

FIG. 7 is a flowchart showing a flow of a motor throttle opening control operation performed by an electronic control unit of the traction control system of the embodiment device.

FIG. 8 is a time chart showing a drive wheel slip convergence effect at the time of turning on a low friction coefficient road in the embodiment device.

FIG. 9 is a time chart showing a drive wheel slip convergence effect when the conventional device turns on a low friction coefficient road.

[Explanation of symbols]

 a throttle valve b valve actuator c driving wheel slip detecting means d lateral acceleration detecting means e longitudinal acceleration detecting means f throttle closing speed setting means g throttle opening speed setting means h throttle controlling means

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-121838 (JP, A) JP-A-2-256835 (JP, A) JP-A-63-151523 (JP, A) JP-A-62-162 10437 (JP, A) JP-A-2-287264 (JP, A) JP-A-64-60413 (JP, A) JP-A 64-12963 (JP, A) Jpn. (58) Field surveyed (Int.Cl. ⁶ , DB name) F02D 9/00-11/10 F02D 41/00-45/00 395 F02D 29/00-29/06

Claims (1)

(57) [Claims] 1. A valve actuator for opening and closing a throttle valve irrespective of accelerator operation, a drive wheel slip detecting means for detecting a slip condition of an engine drive wheel, a lateral acceleration detecting means for detecting a vehicle lateral acceleration, and a vehicle. Longitudinal acceleration detecting means for detecting longitudinal acceleration; throttle closing speed setting means for setting the throttle closing speed to be low as the lateral acceleration and longitudinal acceleration increase; and increasing the throttle opening speed as the lateral acceleration and longitudinal acceleration increase. A throttle opening speed setting means for setting, and when the driving wheel slip detection value is equal to or higher than a predetermined value, a control command for closing the throttle valve is output to the valve actuator according to the set throttle closing speed, and the driving wheel slip detection value is equal to or lower than the predetermined value. The throttle opening speed set at A traction control device for a vehicle, comprising: throttle control means for outputting a control command for opening a throttle valve to the valve actuator.