Motor vehicles – With means for detecting wheel slip during vehicle...
Patent
1993-04-22
1994-11-22
Hill, Mitchell J.
Motor vehicles
With means for detecting wheel slip during vehicle...
36442602, 36442603, 36442605, B60K 2816, B60L 310
Patent
active
053660390
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to an acceleration slip control device for a motor vehicle for improving vehicle acceleration performance by restraining excessive slip (acceleration slip) of driving wheels which occurs during start-up and acceleration of the vehicle.
BACKGROUND ART
A conventional acceleration slip control device for a motor vehicle is designed to begin to control acceleration slip when the speed of a driving wheel has exceeded a reference speed, or when the slip ratio of the driving wheels has exceeded a reference slip ratio. In this acceleration slip control, the opening of the throttle valve is controlled by a feedback control system so that for example the slip ratio of the driving wheels may correspond to a target slip ratio.
The acceleration slip control device in conventional use for motor vehicles, however, has such a problem that if the acceleration slip control is started after the driving wheel speed has exceeded a reference speed, there takes place a delay time between the throttle valve opening and a target opening, resulting in a lowered initial response property of the acceleration slip control.
That is, if throttle valve operation starts upon the detection of an acceleration slip, the driving wheels slip excessively during the period of time delay until the throttle valve opening agrees with the target opening, resulting in an insufficient acceleration performance.
It is, therefore, an object of the present invention to provide an acceleration slip control device for motor vehicles which is capable of realizing a good acceleration performance by presetting the initial throttle valve opening suitable to restrain the acceleration slip in accordance with a predicted occurrence of the acceleration slip.
SUMMARY OF THE INVENTION
In the present invention, the throttle valve opening is preset to a specific initial opening when it is detected that the depth of the depression of an accelerator has exceeded a reference value at which the occurrence of acceleration slip of the driving wheels is predicted prior to the actual acceleration slip. In this case the driving torque produced by an internal combustion engine is delayed in response to the opening of the throttle valve. Accordingly there will sometimes occur acceleration slip of the driving wheels after the setting of the throttle valve opening to a specific initial opening. In the present invention, at this time, the throttle valve is driven quickly, to open from the initial opening to the target opening which is determined in accordance with the acceleration slip of the driving wheels. That is, the opening of the throttle valve is preset to an initial opening adapted to restrain the acceleration slip before the actual occurrence of the acceleration slip, so that the preset initial opening of the throttle valve is positioned close to the target opening during acceleration slip control. It is, therefore, possible for the acceleration slip control device of the present invention to reduce the time required to open the throttle valve from the initial opening to the target opening, as compared with the conventional acceleration slip control device.
The reference value stated above is updated on the basis of the amount of the throttle valve opening (throttle opening) when the acceleration slip is being controlled to an optimum value by the feedback control of the acceleration slip. That is, with an opening of the throttle set to an optimum value by the acceleration slip control of the present invention, it is possible to obtain the optimum acceleration performance on a current road surface on which the motor vehicle is traveling. The reference value of the depth of depression of the accelerator for predicting the occurrence of acceleration slip is updated on the basis of this throttle opening, thereby enabling improving prediction accuracy.
It is preferable that the reference value stated above be renewed on the basis of the condition of vehicle acceleration. That is, for example, the vehicle, entering upon a high
REFERENCES:
patent: 4672934 (1987-06-01), Peter et al.
patent: 4771849 (1988-09-01), Leiber et al.
patent: 4987966 (1991-01-01), Fujita
patent: 5117934 (1992-06-01), Tsuyama et al.
patent: 5163530 (1992-11-01), Nakamura et al.
patent: 5222570 (1993-06-01), Kawamura et al.
Patent Abstract of Japan, vol. 12, No. 105 (M-681)(2952) Apr. 1988 re JP-A- 62-237074.
Hill Mitchell J.
Nippondenso Co. Ltd.
LandOfFree
Acceleration slip control device for a motor vehicle does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Acceleration slip control device for a motor vehicle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Acceleration slip control device for a motor vehicle will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1985466