METHOD FOR ASSESSING THE COMPATABILITY OF BRAKING SYSTEMS OF A VEHICLE COMBINATION AND COMPATIBILITY ASSESSMENT DEVICE

• US 20100217495A1
• Filed: 05/09/2008
• Published: 08/26/2010
• Est. Priority Date: 05/24/2007
• Status: Active Grant

• Current Assignee: ZF CV Systems Europe BV
• Original Assignee: Wabco GmbH (Wabco Holdings Incorporated)
• Inventors: Holst, Hanst, Heise, Bernd, Stender, Axel, Witte, Norbert, Ronnenberg, Udo
• Granted Patent: US 8,543,305 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60T 17/18 Safety devices; Monitoring

Abstract

The invention relates to a method and a device for assessing the compatibility of braking systems of a vehicle combination comprising a tractor and a trailer. According to the invention, an, applied braking power (W_a) for a braking process of the trailer is determined, and a required braking power for the braking process (W_b) of the trailer is determined.

Claims

1. A method for assessing the compatibility of braking systems of a vehicle combination, wherein the vehicle combination has a towing vehicle (100) and a trailer vehicle (50), characterized in that an applied amount of braking energy (W_a) of a braking process of the trailer vehicle (50) is determined and a required amount of braking energy (W_b) of the braking process of the trailer vehicle (50) is determined.

2. The method as claimed in claim 1, characterized in that a variable (G) for assessing the compatibility is determined as a function of the applied amount of braking energy (W_a) and as a function of the required amount of braking energy (W_b).

3. The method as claimed in claim 2, characterized in that the variable (G) is determined as a function of a quotient formed from the applied amount of braking energy (W_a) and the required amount of braking energy (W_b).

4. The method as claimed in claim 1, 2 or 3, characterized in that the applied amount of braking energy (W_a) is determined as a function of at least one wheel circumferential speed (_vRji) of a wheel of the trailer vehicle (51-54) and at least one brake cylinder pressure (p_Bji) of a brake cylinder (38-41) of the trailer vehicle (50).

5. The method as claimed in claim 4, characterized in that the applied amount of braking energy (W_a) is determined by means of the formula

$W_{\mathrm{aj}}=k·$

T ·

∑

i = 1 n 

( p Bji - p A 



N ) ·

v Rji

where W_aj denotes the applied amount of braking energy by a brake cylinder (38-41) of the trailer vehicle (50) and the applied amount of braking energy by a wheel (51-54) braked by means of the brake cylinder (38-41), k denotes a constant, T denotes a sampling time of a control device (42) in the vehicle combination, p_Bji denotes the pressure prevailing in the brake cylinder (38-41), p_AN denotes an application pressure and v_Rji, denotes a wheel circumferential speed of the wheel (51-54) braked by the brake cylinder (38-41).

6. The method as claimed in one of the preceding claims, characterized in that the required amount of braking energy (W_b) is determined by means of the formula

$W_b=\frac{m_A·}{}$

( v An - v A 



1 ) 2 2

where W_b denotes the required amount of braking energy, m_A denotes the mass of the trailer vehicle (50), v_A1 denotes the speed of the trailer vehicle (50) at the start of the braking process, and v_An denotes the speed of the trailer vehicle (50) after the end of the braking process.

7. The method as claimed in one of the preceding claims 2 to 6, characterized in that the variable (G) is determined on the basis of the applied amounts of braking energy (W_a) which are determined for a plurality of braking processes, and the required amounts of braking energy (W_b) which are determined for the plurality of braking processes.

8. The method as claimed in one of the preceding claims 2 to 7, characterized in that the variable (G) is output.

9. The method as claimed in one of the preceding claims, characterized in that the applied amount of braking energy (W_a) and the required amount of braking energy (W_b) and/or the variable (G) are transmitted to a receiver unit by means of a telematics interface.

10. The method as claimed in one of the preceding claims, characterized in that the applied amount of braking energy (W_a) and the required amount of braking energy (W_b) and/or the variable (G) are determined during the normal driving mode of the vehicle combination.

11. The method as claimed in one of the preceding claims, characterized in that the applied amount of braking energy (W_a) and the required amount of braking energy (W_b) and/or the variable (G) are determined automatically.

12. The method as claimed in one of the preceding claims 2 to 11, characterized in that a braking process which takes place on a roadway whose longitudinal inclination exceeds a specific limiting value is not taken into account for the determination of the variable (G).

13. The method as claimed in claim 12, characterized in that the braking process which takes place on a roadway whose longitudinal inclination exceeds a specific limiting value is detected by a speed gradient which is sensed before the braking process.

14. The method as claimed in one of the preceding claims 2 to 13, characterized in that the braking systems of the vehicle combination can be adjusted as a function of the variable (G).

15. The method as claimed in one of the preceding claims, characterized in that the applied amount of braking energy (W_a) and the required amount of braking energy (W_b) are stored in a control device (42) in the vehicle combination, and the applied amount of braking energy (W_a) and the required amount of braking energy (W_b) can be read out via an interface.

16. A device for assessing the compatibility of braking systems of a vehicle combination, wherein the vehicle combination has a towing vehicle (100) and a trailer vehicle (50), characterized by means which determine an applied amount of braking energy (W_a) of a braking process of the trailer vehicle (50) and determine a required amount of braking energy (W_b) of the braking process of the trailer vehicle (50).