Method of controlling anti-Lock brake system for vehicles and method of finding control point in ABS
First Claim
1. A method of controlling an anti-lock brake system for vehicles wherein when a vehicle having an anti-lock brake system mounted thereon has emergency brake applied thereto, a change in road surface friction force or road surface friction coefficient due to the increased brake pressure is detected by a road surface friction force detecting device or a road surface friction coefficient detecting device, said method being characterized in that to decide the optimum control start point concomitant with the increase of the signal value of road surface friction force F or road surface friction coefficient μ
- detected by the road surface friction force detecting device or road surface friction coefficient detecting device, use is made of means for eliminating disturbance sources which impede such decision.
1 Assignment
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Accused Products
Abstract
In an anti-lock brake system mounted on a vehicle wherein when the vehicle is braked in an emergency during running, an increase in the road surface friction force or road surface friction coefficient owing to an increase in the brake pressure is detected by a road surface friction force detecting device or road surface friction coefficient detecting device. The optimum control start point associated with an increase in the signal value of the road surface friction force F or road surface friction coefficient μ provided by the road surface friction force detecting device or road surface friction coefficient detecting device is decided by using a decrease in the wheel speed, i.e., by using the wheel speed ω or dω/dt. Thereafter, from the point where the specified value of control based on F or μ, or dF/dt or dμ/dt, the brake pressure is moved from the pressure increasing mode to the pressure retaining or decreasing mode.
38 Citations
26 Claims
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1. A method of controlling an anti-lock brake system for vehicles wherein when a vehicle having an anti-lock brake system mounted thereon has emergency brake applied thereto, a change in road surface friction force or road surface friction coefficient due to the increased brake pressure is detected by a road surface friction force detecting device or a road surface friction coefficient detecting device,
said method being characterized in that to decide the optimum control start point concomitant with the increase of the signal value of road surface friction force F or road surface friction coefficient μ - detected by the road surface friction force detecting device or road surface friction coefficient detecting device, use is made of means for eliminating disturbance sources which impede such decision.
- View Dependent Claims (5, 6)
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2. A method of controlling an anti-lock brake system for vehicles, wherein when a vehicle having an anti-lock brake system mounted thereon has emergency brake applied thereto, a change in road surface friction force or road surface friction coefficient due to the increased brake pressure is detected by a road surface friction force detecting device or a road surface friction coefficient detecting device,
said method being characterized in that the optimum control start point concomitant with the increase of the signal value of road surface friction force F or road surface friction coefficient μ - due to the increased brake pressure detected by the road surface friction force detecting device or road surface friction coefficient detecting device is decided by a drop in the wheel speed, that is, by using the wheel speed ω
or dω
/dt, and then from the point where the specified value of control by F or μ
or by dF/dt or dμ
/dt is reached, the brake pressure is shifted from the pressure increasing mode to the pressure retaining or decreasing mode, so as to eliminate disturbance sources.
- due to the increased brake pressure detected by the road surface friction force detecting device or road surface friction coefficient detecting device is decided by a drop in the wheel speed, that is, by using the wheel speed ω
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3. A method of controlling an anti-lock brake system for vehicles wherein when a vehicle having an anti-lock brake system mounted thereon has emergency brake applied thereto, a change in road surface friction force or road surface friction coefficient due to the increased brake pressure is detected by a road surface friction force detecting device or a road surface friction coefficient detecting device,
said method being characterized in that the optimum control start point concomitant with the increase of the signal value of road surface friction force F or road surface friction coefficient μ - due to the increased brake pressure detected by the road surface friction force detecting device or road surface friction coefficient detecting device is decided by a drop in the vehicle acceleration decided by dV/dt using an acceleration sensor, and then from the point where the specified value of control by F or μ
or by dF/dt or dμ
/dt is reached, the brake pressure is shifted from the pressure increasing mode to the pressure retaining or decreasing mode, so as to eliminate disturbance sources.
- due to the increased brake pressure detected by the road surface friction force detecting device or road surface friction coefficient detecting device is decided by a drop in the vehicle acceleration decided by dV/dt using an acceleration sensor, and then from the point where the specified value of control by F or μ
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4. A method of controlling an anti-lock brake system for vehicles wherein when a vehicle having an anti-lock brake system mounted thereon has emergency brake applied thereto, a change in road surface friction force or road surface friction coefficient due to the increased brake pressure is detected by a road surface friction force detecting device or a road surface friction coefficient detecting device,
said method being characterized in that the optimum control start point concomitant with the increase of the signal value of road surface friction force F or road surface friction coefficient μ - detected by the road surface friction force detecting device or road surface friction coefficient detecting device is decided by both the wheel speed ω
or dω
/dt and dV/dt, and then from the point where the specified value of control by F or μ
or by dF/dt or dμ
/dt is reached, the brake pressure is shifted from the pressure increasing mode to the pressure retaining or decreasing mode, so as to eliminate disturbance sources.
- detected by the road surface friction force detecting device or road surface friction coefficient detecting device is decided by both the wheel speed ω
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7. A method of controlling an anti-lock brake system for vehicles wherein when a vehicle having an anti-lock brake system mounted thereon has emergency brake applied thereto, a change in road surface friction force or road surface friction coefficient due to the increased brake pressure is detected by a road surface friction force detecting device or a road surface friction coefficient detecting device,
said method being characterized in that after the maximum value of the signal value of road surface friction force F or road surface friction coefficient μ - detected by the road surface friction detecting device or road surface friction coefficient detecting device has been ascertained, fixed lower limits are provided for the approximate maximum F value or approximate maximum μ
value and the maximum F value or maximum μ
value and the brake pressure is controlled such that F or μ
is stably retained in the range, thus eliminating disturbance sources. - View Dependent Claims (9, 10, 13)
- detected by the road surface friction detecting device or road surface friction coefficient detecting device has been ascertained, fixed lower limits are provided for the approximate maximum F value or approximate maximum μ
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8. A method of controlling an anti-lock brake system for vehicles wherein when a vehicle having an anti-lock brake system mounted thereon has emergency brake applied thereto, a change in road surface friction force or road surface friction coefficient due to the increased brake pressure is detected by a road surface friction force detecting device or a road surface friction coefficient detecting device,
said method being characterized in that after the maximum value of the signal value of road surface friction force F or road surface friction coefficient μ - detected by the road surface friction detecting device or road surface friction coefficient detecting device has been ascertained, fixed lower limits are provided for the approximate maximum F value or approximate maximum μ
value and the maximum F value or maximum μ
value and the brake pressure is controlled by being increased or decreased in the range in which F or μ
is retained, thus eliminating disturbance sources.
- detected by the road surface friction detecting device or road surface friction coefficient detecting device has been ascertained, fixed lower limits are provided for the approximate maximum F value or approximate maximum μ
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11. A method of controlling an anti-lock brake system for vehicles, characterized in that in the case where the maximum value of the signal value of road surface friction force F or road surface friction coefficient μ
- detected by the road surface friction force detecting device or road surface friction coefficient detecting device can hardly be ascertained, quasi-F or quasi-μ
is found between the maximum F value or maximum μ
value and the minimum F value or minimum μ
value within a given period of time, and the brake pressure control is effected corresponding to such quasi-F or quasi-μ
, thus eliminating disturbance sources. - View Dependent Claims (12)
- detected by the road surface friction force detecting device or road surface friction coefficient detecting device can hardly be ascertained, quasi-F or quasi-μ
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14. A method of detecting the control point in an ABS having a stress sensor which provides an output proportional to the road surface friction F or road surface friction coefficient μ
- having mixed therein a crosstalk component, such as brake torque T, and to the brake torque T, said method being characterized in that it uses adjusting means for making adjustment from the rise of the brake start such that detected signals of F or μ and
T are adjusted in ratio or made equal in value, and decision means for deciding the control point by a change in said ratio or in adjustment coefficient, wherein the timing of the control point is detected by the size of a change in the ration of detected signals of F or μ and
T or in adjustment coefficient. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22)
- having mixed therein a crosstalk component, such as brake torque T, and to the brake torque T, said method being characterized in that it uses adjusting means for making adjustment from the rise of the brake start such that detected signals of F or μ and
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23. A method of detecting the control point in an ABS having a stress sensor which provides an output proportional to the road surface friction F or road surface friction coefficient μ
- having mixed therein a crosstalk component, such as brake torque T, and to the brake torque T, said method being characterized in that it uses adjusting means for adjusting the ratio of detected signals of F or μ and
T, and decision means for deciding the control point by a change in F-T value from its value after adjustment, wherein the timing for the control point is detected by said change in the F-T value. - View Dependent Claims (25, 26)
- having mixed therein a crosstalk component, such as brake torque T, and to the brake torque T, said method being characterized in that it uses adjusting means for adjusting the ratio of detected signals of F or μ and
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24. A method of detecting the control point in an ABS having a stress sensor which provides an output proportional to the road surface friction force F or road surface friction coefficient μ
- and the brake torque T, said method being characterized in that the timing for the control point is detected by a change in the F-T value during brake control.
Specification