Method for controlling the brake system of a vehicle train

• US 7,413,266 B2
• Filed: 10/10/2003
• Issued: 08/19/2008
• Est. Priority Date: 10/12/2002
• Status: Active Grant

• Current Assignee: Wabco GmbH (Wabco Holdings Incorporated)
• Original Assignee: Wabco GmbH (Wabco Holdings Incorporated)
• Inventors: Lenz, Thomas, Ruhnau, Gerhard, Meyer, Benno
• Primary Examiner(s): Nguyen; Xuan Lan
• Application Number:
  US10/683,453
• Publication Number:
  US 20040119334A1
• Time in Patent Office: 1,775 Days
• Field of Search: 303/7, 303/147, 303/150, 701/70, 701/72
• US Class Current: 303/150
• CPC Class Codes: B60T 2230/03 Overturn, rollover
• CPC Class Codes: B60T 8/1708 for lorries or tractor-trailer combinations
• CPC Class Codes: B60T 8/17554 specially adapted for enhancing stability around the vehicles longitudinal axle, i.e. roll-over prevention road vehicle drive control systems for roll-over prevention otherwise than by controlling a particular sub-unit B60W30/04
• CPC Class Codes: B60T 8/248 Trailer sway, e.g. for preventing jackknifing

Abstract

An improved method and associated system for controlling the brake system of a vehicle train including a tractor vehicle and a trailer vehicle, wherein a control device disposed in the tractor vehicle is adapted to initiate automatic braking of the trailer vehicle, and wherein the conditions of the driving roadway, especially the coefficient of friction, are taken into account in braking of the trailer vehicle. The intensity of braking of the trailer vehicle is reduced by the control device when a coefficient of friction smaller than a predetermined minimum value is detected between the vehicle train or parts thereof and the driving roadway. One application of the invention is in load trains equipped with means for preventing rollover or overturning.

Claims

1. A method for controlling the brake system of a vehicle train, the vehicle train including a tractor vehicle and a trailer vehicle, a control device in the tractor vehicle arranged and constructed to initiate automatic braking of the trailer vehicle when a vehicle train rollover danger is presented, the method comprising the steps of detecting a coefficient of friction between the roadway on which the vehicle train travels and the vehicle train, determining whether the coefficient of friction is smaller than a predetermined minimum value when an anti-wheel-lock braking function is at least one of absent in said trailer vehicle and inoperative in said trailer vehicle, and reducing intensity of automatic braking of the trailer vehicle utilizing the control device in the tractor vehicle when the coefficient of friction is smaller than the predetermined minimum value.

2. The method according to claim 1, wherein the step of determining whether the coefficient of friction is smaller than a predetermined minimum value includes determining a response of a wheel-lock protection function in the tractor vehicle.

3. The method according to claim 2, wherein the step of determining a response of a wheel-lock protection function in the tractor vehicle includes determining a response of the wheel-lock protection function on an outer wheel of a rear axle of the tractor vehicle relative to a curve of the roadway.

4. The method according to claim 1, wherein the step of determining whether the coefficient of friction is smaller than a predetermined minimum value includes measuring total deceleration of the vehicle train, comparing the measured total deceleration with a value expected for the total deceleration on the basis of actuation of the brake system, and determining if the measured total deceleration is smaller than the expected value.

5. The method according to claim 1, wherein the intensity of braking of the trailer vehicle is defined as a function of the mass of the vehicle train.

7. The method according to claim 1, wherein the step of reducing the intensity of braking of the trailer vehicle is effected by output of a signal-pulse train to a device arranged and constructed to control braking of the trailer vehicle, the signal-pulse train being selected from a predetermined set of signal-pulse trains.

6. A method for controlling the brake system of a vehicle train, the vehicle train including a tractor vehicle and a trailer vehicle, a control device in the tractor vehicle arranged and constructed to initiate automatic braking of the trailer vehicle, the method comprising the steps of detecting a coefficient of friction between the roadway on which the vehicle train travels and the vehicle train, determining whether the coefficient of friction is smaller than a predetermined minimum value, reducing the intensity of braking of the trailer vehicle utilizing the control device when the coefficient of friction is smaller than the predetermined minimum value, analyzing signals of a data interface between the tractor vehicle and the trailer vehicle, determining if a wheel-lock protection function in the trailer vehicle is operative based on the analysis of the signals, and preventing reduction of the intensity of braking of the trailer vehicle if the wheel-lock protection function in the trailer is operative.

8. A method for controlling the braking system of a vehicle train, the vehicle train including a tractor vehicle and a trailer vehicle, a control device in the tractor vehicle arranged and constructed to automatically brake the trailer vehicle, the method comprising the steps of determining whether a vehicle train rollover condition is present, automatically braking the trailer vehicle if a rollover condition is determined, determining whether a wheel-lock protection function of the trailer vehicle is at least one of present in said trailer vehicle and operative in said trailer vehicle, determining if a coefficient of friction between the roadway on which the vehicle train travels and the vehicle train is smaller than a predetermined minimum value when said wheel-lock protection function is at least one of absent in said trailer vehicle and inoperative in said trailer vehicle, selecting a signal-pulse train for reducing intensity of automatic braking of said trailer vehicle from a predetermined set of signal-pulse trains, and outputting the selected signal-pulse train utilizing said control device to actuate a device arranged and constructed to control braking of the trailer vehicle.

9. A system for controlling the brake system of a vehicle train, the vehicle train including a tractor vehicle and a trailer vehicle, the system comprising means associated with the tractor vehicle arranged and constructed to initiate automatic braking of the trailer vehicle when a vehicle train rollover danger is presented, means for detecting a coefficient of friction between the roadway on which the vehicle train travels and the vehicle train, means for determining whether the coefficient of friction is smaller than a predetermined minimum value when an anti-wheel-lock braking function is at least one of absent in said trailer vehicle and inoperative in said trailer vehicle, and means associated with the tractor vehicle for reducing intensity of automatic braking of the trailer vehicle when the coefficient of friction is smaller than the predetermined minimum value.

10. The system according to claim 9, wherein said means for determining whether the coefficient of friction is smaller than a predetermined minimum value includes means for determining a response of a wheel-lock protection function in the tractor vehicle.

11. The system according to claim 10, wherein said step of determining a response of a wheel-lock protection function in the tractor vehicle includes determining a response of the wheel-lock protection function on an outer wheel of a rear axle of the tractor vehicle relative to a curve of the roadway.

12. The system according to claim 9, wherein said means for determining whether the coefficient of friction is smaller than a predetermined minimum value includes means for measuring total deceleration of the vehicle train, means for comparing the measured total deceleration with a value expected for the total deceleration on the basis of actuation of the brake system, and means for determining if the measured total deceleration is smaller than the expected value.

13. The system according to claim 9, wherein the intensity of braking of the trailer vehicle is defined as a function of the mass of the vehicle train.

15. The system according to claim 9, wherein the means for reducing the intensity of braking of the trailer vehicle is responsive to output of a signal-pulse train, the signal-pulse train being selected from a predetermined set of signal-pulse trains.

14. A system for controlling the brake system of a vehicle train, the vehicle train including a tractor vehicle and a trailer vehicle, the system comprising means associated with the tractor vehicle arranged and constructed to initiate automatic braking of the trailer vehicle, means for detecting a coefficient of friction between the roadway on which the vehicle train travels and the vehicle train, means for determining whether the coefficient of friction is smaller than a predetermined minimum value, means for reducing the intensity of braking of the trailer vehicle when the coefficient of friction is smaller than. the predetermined minimum value, means for analyzing signals of a data interface between the tractor vehicle and the trailer vehicle, means for determining if a wheel-lock protection function in the trailer vehicle is operative based on the analysis of the signals, and means for preventing reduction of the intensity of braking of the trailer vehicle if the wheel-lock protection function in the trailer is operative.

16. A system for controlling the brake system of a vehicle train, the vehicle train including a tractor vehicle and a trailer vehicle, the system comprising means for determining whether a vehicle train rollover condition is presented, means associated with the tractor vehicle arranged and constructed to automatically brake the trailer vehicle when a vehicle train rollover condition is determined, means for determining whether a wheel-lock protection function of the trailer vehicle is at least one of present in said trailer vehicle and operative in said trailer vehicle, means for determining if a coefficient of friction between the roadway on which the vehicle train travels and the vehicle train is smaller than a predetermined minimum value when said wheel-lock protection function is at least one of absent in said trailer vehicle and inoperative in said trailer vehicle, means for selecting a signal-pulse train from a predetermined set of signal-pulse trains for reducing intensity of automatic braking of said trailer vehicle when said coefficient of friction is smaller than said predetermined minimum value, and means responsive to the selected signal-pulse train arranged and constructed to control braking of the trailer vehicle.