Method for reducing speed of a vehicle combination

Abstract

The invention relates to a method for decelerating a vehicle combination (7) having a towing vehicle (5) and at least one trailer (6) having its own trailer brake facility. A brake control unit (30) of the towing vehicle brake facility (3) monitors the braking behavior of the towing vehicle (5) or of the vehicle combination (7) and sets the brake pressure (P) on the wheel brakes (13) of the relevant wheels (10) of the towing vehicle (5) and the trailer brake pressure (P-A) as required. The brake control unit (30) also detects a deceleration request (41) of the driver to the service brake facility (17) and monitors whether at least one predefined safety criterion (1, 2) is fulfilled during the actuation (54) of the service brake facility (17) depending on at least one continuously ascertained braking state variable. After the service brake facility (17) has been requested by the driver, the stability of the vehicle combination is ensured in every driving situation by the fact that the still to be implemented part (52) of the deceleration request (41) to the service brake facility (17) is implemented via the trailer brake facility (4) if the safety criterion (1, 2) is fulfilled.

Description

Technical Field

[0001] The present invention relates to a method for decelerating a vehicle assembly having a tractor and at least one trailer having its own trailer braking system. Background Technology

[0002] The tractor and at least one trailer in the vehicle assembly each have pneumatically operated wheel brakes on each wheel. The braking effect of the wheel brakes can be adjusted by applying individual braking pressure. Whenever the driver operates the service brake valve via the brake pedal, braking pressure is connected to the wheel brakes of the tractor through the service brake valve of the tractor's braking system.

[0003] DE 10 2016 013 054 A1 discloses a method for decelerating a vehicle combination, wherein the trailer has its own trailer braking system. The wheel brakes of the trailer braking system are operated via trailer braking pressure, which is adjusted by the tractor braking system. The brake control unit of the tractor braking system monitors the braking behavior of the tractor or the vehicle combination and, as needed, adjusts the respective braking pressures applied to the wheel brakes of the relevant wheels of the tractor and the trailer braking pressure. In known arrangements, the tractor's brake control unit and the trailer's brake electronics communicate with each other. The trailer's brake electronics inform the tractor's brake control unit of brake slip rate information, which includes information about the brake slip rate on a specific axle unit of the trailer. The tractor's brake control unit determines the differential slip rate based on the trailer's brake slip rate information. If the assessment of the poor brake slip ratio results in a braking demand on the trailer, the tractor's brake control unit adjusts the corresponding trailer brake pressure, which is then supplied to the trailer braking system via the trailer control valve.

[0004] In particular, continuous braking systems are known for commercial vehicles, which enable more sustained and wear-free braking without reducing braking power. Because ordinary service brakes are not suitable for continuous operation and may tend to overheat or even lead to brake failure (fade-off) over extended periods, continuous braking effectively relieves the load on service brakes. In commercial vehicles, two types of continuous braking systems are generally used: engine braking systems and so-called retarder systems. DE 101 44302A1 discloses a braking system for a vehicle combination that includes both service brakes and continuous braking systems. To optimally utilize the wear-free advantage of continuous braking, known braking systems are configured to primarily or solely use the continuous brakes when braking force from the service brakes, depending on the respective driving conditions, is sufficient. The continuous braking system is only used in conjunction with the service brakes when more intense braking occurs where the continuous brakes' braking force is insufficient. Known braking systems include a monitoring device that determines the maximum possible continuous braking force that can be generated by the continuous brakes depending on the current driving conditions. The service braking system and the continuous braking system are driven and controlled in the tractor of the vehicle combination based on the current driving conditions, or more precisely, driven and controlled centrally by means of the brake pedal, wherein the distribution of braking force is automatically controlled.

[0005] The driver's requirement for continuous braking of the tractor unit may jeopardize the driving stability of a vehicle assembly consisting of multiple parts in critical driving situations. Summary of the Invention

[0006] The objective of this invention is to ensure the stability of the vehicle combination in each driving situation after the driver requests continuous braking in a method for decelerating a vehicle combination.

[0007] This task is solved according to the present invention by means of the following method. In a method for decelerating a vehicle assembly, the vehicle assembly includes a tractor and at least one trailer with its own trailer braking system. A brake control unit of the tractor braking system monitors the braking behavior of the tractor or the vehicle assembly and adjusts the respective braking pressures on the wheel brakes of the relevant wheels of the tractor and the trailer braking pressure as needed. The brake control unit detects a driver's manual deceleration request to the continuous braking system and monitors whether at least one pre-defined safety criterion is met during the driving control of the continuous braking system based on at least one continuously known braking state parameter. If the safety criterion is met, the unfulfilled portion of the deceleration request to the continuous braking system is achieved via the trailer braking system. The brake electronics of the trailer braking system detect the brake slip ratio value of the trailer wheels and inform the brake control unit of the tractor braking system of an information signal containing information about the brake slip ratio value of the trailer. The brake control unit of the tractor braking system adjusts a pre-defined slip ratio difference between the tractor and the trailer by adjusting the braking pressure and the trailer braking pressure.

[0008] According to the present invention, after the driver manually requests deceleration via a lever or switching device using the continuous braking system, the brake control unit detects the driver's deceleration request to the continuous braking system. During the driving control of the continuous braking system based on the driver's deceleration request, at least one pre-given safety criterion is monitored based on at least one continuously known braking state parameter. If the safety criterion is met when the deceleration request to the continuous braking system is implemented, the remaining portion of the deceleration request to the continuous braking system is achieved via the trailer braking system. Instead of outputting a value higher than the current driver's braking request to the control unit of the continuous braking system, the system switches to achieving further deceleration via the trailer braking system based on meeting the safety criterion. To this end, the brake control unit of the tractor braking system prompts the adjustment of the corresponding trailer braking pressure to the trailer braking system.

[0009] In an advantageous embodiment of the invention, a first safety criterion is predetermined, specifying the critical driving conditions of the vehicle combination and a maximum speed set for these conditions. If this first safety criterion is met, the unfulfilled portion of the deceleration requirement to be achieved by the continuous braking system is alternatively achieved via the trailer braking system. The current speed of the vehicle combination is considered as a first braking state parameter for monitoring whether the safety criterion is met and compared with the maximum speed. If the current speed of the vehicle combination reaches the predetermined maximum speed, the continuous braking system is no longer supplied with a higher braking torque to be applied by it, and the unfulfilled portion of the deceleration requested by the driver is achieved not by the continuous braking system but instead via the trailer braking system.

[0010] As critical driving conditions, maximum speeds are pre-defined for these conditions to allow the remaining deceleration requirements of the continuous braking system to be switched via the trailer braking system. In particular, one of the following critical driving conditions is pre-defined:

[0011] - Driving on more pronounced curves, either currently or identified as upcoming, such as at a highway exit or on a serpentine course.

[0012] - Currently or identified as upcoming driving on a downhill road.

[0013] - The outside temperature is below, for example, 3 degrees Celsius.

[0014] - Slippery or snow-covered driveways

[0015] - The axle load on the axle under continuous braking is lower than the permissible axle load (unloaded / partially loaded).

[0016] - The mass of the tractor is relatively small compared to its permissible mass (unloaded / partially loaded), while the mass of the trailer is relatively high.

[0017] The evaluation of the above driving conditions is made in particular with consideration of the braking power capacity of the continuous braking system and the vehicle speed at the start of braking.

[0018] The braking slip ratio value, representing the wheel slip ratio of the wheels of the axle on which the continuous braking system is applied, or the axle-related braking slip ratio value of that axle, is used as a second braking state parameter. The braking slip ratio value representing the wheel slip ratio is compared with a slip ratio boundary value predetermined as a second safety criterion. In the case where the tractor braking system is equipped with an anti-lock braking system (ABS), the slip ratio boundary value satisfying the safety criterion is predetermined to be less than the intervention threshold of the ABS, meaning that the ABS responds to slip at this slip ratio. In an advantageous embodiment of the invention, the slip ratio boundary value is predetermined with a certain gap from the intervention threshold at which the tractor braking system's ABS responds.

[0019] Therefore, in driving situations where stability is critical, the trailer braking system is activated when the brake slip ratio of the tractor's axle, which is under continuous braking, is low; more precisely, activation occurs when the brake slip ratio is below the intervention threshold of the tractor's anti-lock braking system. Thus, severe temporary underbraking of the vehicle combination due to the abandonment of continuous braking by the anti-lock braking system is avoided. Furthermore, in driving situations where stability is critical and continuous braking is subsequently abandoned due to the anti-lock braking system, the trailer braking system is activated, thereby reducing the need for the driver to overcome this situation. Without the method according to the invention, the driver must first operate the brake pedal to activate the service braking system, where typically the tractor first builds up effective braking force and thus the trailer is pushed forward.

[0020] If, upon detecting a pre-defined critical driving condition of the vehicle combination, the deceleration requirement of the continuous braking system is increased to the extent that the trailer braking system needs to achieve, then the risk to the driving stability of the vehicle combination is further suppressed. Advantageously, immediately after braking begins, the tractor's brake control unit outputs a lower braking requirement, matching the situation, to the continuous braking system or its control unit.

[0021] Safety in terms of driving stability is particularly improved in vehicle assemblies where the trailer braking system has its own anti-lock braking system (ABS), wherein the braking electronics of the trailer braking system detect the braking slip ratio of the trailer wheels and inform the tractor's braking control unit of an information signal containing the braking slip ratio of the trailer. In this embodiment according to the invention, the tractor's braking control unit adjusts a predetermined slip ratio difference between the tractor and trailer by adjusting the braking pressure and the trailer braking pressure. This results in deceleration of the vehicle assembly, which occurs when the continuous braking system brakes the vehicle assembly alone. If the driver applies braking to the vehicle assembly via the continuous braking system, the tractor's braking control unit adapts to determine the deceleration effect of the continuous braking system on the vehicle assembly.

[0022] The tractor's brake control unit uses the trailer's brake slip ratio information as a basis for obtaining the actual brake slip ratio difference. This information is communicated to the tractor's brake control unit via a communication link connected to the brake electronics of the trailer's braking system. If an evaluation of the brake slip ratio difference based on a pre-defined difference between the tractor and trailer results in a braking demand on the trailer, the tractor's brake control unit adjusts the corresponding trailer braking pressure. Attached Figure Description

[0023] Embodiments of the present invention are explained in detail below with reference to the accompanying drawings. Wherein:

[0024] Figure 1 A simplified diagram showing the pneumatic and electrical braking system of a vehicle combination with a tractor and a trailer;

[0025] Figure 2 Showing the method for using according to Figure 1 A flowchart illustrating an embodiment of a method for decelerating a combination of vehicles. Detailed Implementation

[0026] Figure 1 The diagram shows the electro-pneumatic braking system of the vehicle assembly, specifically the tractor braking system 3 of the tractor unit in vehicle assembly 7 and the trailer braking system 4 of the trailer unit 6. In the diagram, electrical wiring is shown as solid lines, while pneumatic wiring is shown as dashed lines. In the illustrated embodiment, the tractor unit 5 includes two axles 8 and 9, on which wheels 10 are arranged on both sides. The trailer unit 6 also has two trailer axles 12 and 14, each with wheels 10. For braking the wheels 10, each wheel 10 is equipped with a pneumatically operated wheel brake 13, which is part of the respective service braking system of the vehicles in vehicle assembly 7.

[0027] A brake pedal 15 is installed in the cab of the tractor 5, and the brake pedal is coupled to the service brake valve 16. The driver of the tractor 5 can open the pneumatic brake lines 17 and 18 between the pressure medium reservoirs 19 and 20 and the wheel brakes 13 by operating the brake pedal 15.

[0028] In the illustrated embodiment, the wheel brakes 13 of the front axle 8 of the tractor are associated with a common first braking circuit 21, while the wheel brakes 13 of the rear wheels 9 can be operated via a second braking circuit 22. Here, a first pressure medium reservoir 19 is associated with the first braking circuit 21. The second braking circuit 22 of the rear axle 9 is supplied with pressure medium via a second pressure medium reservoir 20. The second braking circuit 22 is constructed similarly to the first braking circuit 21.

[0029] Within the tractor braking system 3 and the trailer braking system 4, each wheel brake 13 is connected to a pressure control valve 27, which is electrically controllable. To receive control signals 28, the pressure control valve 27 of the tractor braking system 3 is connected to the brake control unit 30. The pressure control valve 27 of the trailer braking system 4 is connected to the brake electronics 31. Each pressure control valve 27 is a combination of at least two magnet valves, namely, an inlet valve 32 and an outlet valve 33. The inlet valve 32 is, in principle, used for pressure increase or pressure maintenance, while the outlet valve 33 is opened to reduce braking pressure and vent the connected brake cylinders. The inlet valve 32 and outlet valve 33 of the pressure control valve 27 are preferably two-position two-way valves.

[0030] The tractor braking system 3 includes a coupling joint 23 to which the trailer braking system 4 of the trailer 6 can be coupled. Through the coupling joint 23, the tractor braking system 3 provides pneumatic trailer braking pressure PA to the trailer braking system 4. Here, a trailer control valve 24 is provided to the coupling joint 23, which controls the connection between the third pressure medium reservoir 25 and the pneumatic coupling joint 23. The trailer braking system 4 has a trailer braking circuit 26, in which trailer braking pressure PA is present, and can connect the trailer braking pressure to all wheel brakes 13 of the trailer braking system 4. The brake control unit 30 of the tractor braking system 3 is responsible for operating the trailer control valve 24. For this purpose, the tractor braking system 3 has a trailer pressure control valve 38, which is constructed similarly to the pressure control valve 27 of the wheel brakes 13, and the inlet valve 32 and outlet valve 33 of the pressure control valve are actuated before the brake control unit 30 of the tractor braking system 3.

[0031] The brake control unit 30 and brake electronics 31 are configured and set to influence the braking pressure within their respective portions of the vehicle assembly 7 as needed. For this purpose, the rotational behavior of each wheel 10 is monitored. Each wheel 10 of the tractor 5 and each wheel 10 of the trailer 6 is equipped with a speed sensor 34, which generates a measurement signal 35 containing information about the rotational behavior of each wheel 10. The speed of each wheel is determined from the measurement signal 35 of the speed sensor 34. Figure 2 The reference numerals v1, v2, v3, v4 in the attached diagrams are used in the anti-lock braking system (ABS). Figure 2 Reference numeral 36 in the attached figure is considered to represent the braking slip ratio value representing the wheel slip ratio at which wheel slip occurs. The brake control unit 30, speed sensor 34, and pressure control valve 27 of the tractor braking system 3 are the main components of the anti-lock braking system 36 of the tractor braking system 3. The brake control unit 30 monitors the locking tendency of each wheel 10 via the speed sensor 34 or by evaluating the measurement signal 35 of the speed sensor. When it is determined that an individual wheel 10 has a locking tendency, the brake control unit drives one or more pressure control valves 27 and along the ABS intervention threshold ( Figure 2 (See attached figure 44) Adjust the braking pressure applied to the wheel brake 13 to resist wheel lock-up.

[0032] Trailer 6 or its trailer braking system 4 has its own anti-lock braking system with braking electronics 31, which, similar to brake control unit 30, monitors the tendency of the wheels 10 of trailer 6 to lock up via speed sensor 34 or evaluation of the measurement signal 35 from the speed sensor. When a lock-up tendency is identified in an individual wheel 10, braking electronics 31 counteracts the lock-up of the wheel 10 by actuating one or more pressure control valves 27 and adjusting the braking pressure applied to the wheel brakes along the slip ratio boundary.

[0033] The brake control unit 30 of the tractor 5 receives a service braking request 39 and infers from this that the driver of the vehicle assembly 7 requests deceleration. For this purpose, a brake signal detector is coupled to the position of the brake pedal 15 in the driver's cab. If the driver of the tractor 5 operates the brake pedal 15, the corresponding service braking request 39 is transmitted to the brake control unit 30. The brake control unit 30 determines the brake pressure to be adjusted based on the service braking request 39 and the corresponding characteristic curve stored in the integrated characteristic curve memory 37.

[0034] In addition to the tractor braking system 3, the tractor vehicle 5 also has a continuous braking system 17. In the illustrated embodiment, the continuous braking system 17 acts on the rear axle 9 of the tractor vehicle 5. A control unit 46 is attached to the continuous braking system 17. The control unit 46 and the actuator of the continuous braking system 17 are interconnected via a signal line 18. The control unit 46 of the continuous braking system 17 controls the actuator via the signal line 18 and achieves braking power according to the deceleration requirement 41. In other words, the continuous braking system is controlled via the signal line 18. Figure 2 Reference numeral 54 in the attached diagram, wherein the status information of the continuous braking device 17 can be detected simultaneously via signal line 18. Figure 2 (Ref. 55 in the attached figures). To input the deceleration request 41 to the continuous braking device 17, a lever 49 or other operating device is provided, through which the driver can put the continuous braking device 17 into operation. The deceleration request 41 to the continuous braking device 17 can be performed in stages or continuously.

[0035] The control unit 46 of the continuous braking system communicates with the brake control unit 30 of the tractor braking system via signal line 45. Through signal line 45, the brake control unit 30 receives status information 55 of the continuous braking system 17, such as permission for manual use of the continuous brake (main switch, internal locking, etc.). Furthermore, the status information 55 may include the rated torque of the continuous braking system 17 or the status of the continuous braking system (stepped or stepless). During braking, the current braking torque of the continuous braking system 17 is communicated. Specifically, the status information 55 communicated by the control unit 46 includes a driver's request for deceleration by the continuous braking system 17, i.e., a pre-defined deceleration request 41 to the continuous braking system 17 via the operating lever 49.

[0036] Therefore, the brake control unit 30 of the tractor braking system 3 detects the driver's manual deceleration request 41 to the continuous braking system 17 via communication with the control unit 46 of the continuous braking system 17.

[0037] During the continuous braking event 17, the brake control unit 30 detects the driver's deceleration request toward the continuous braking event 17, and, in accordance with the following... Figure 2 The method described is used to monitor the deceleration process.

[0038] If the driver of the vehicle assembly wishes to engage the continuous braking system 17 and operates the lever 49, a deceleration requirement 41 is pre-defined corresponding to the manual operation of the control unit 46 of the continuous braking system 17. The control unit 46 and the continuous braking system 17 are connected via control line 18 ( Figure 1They are interconnected by transmitting signals, so that the drive control 54 of the continuous braking device 17 can be performed by the control unit 46. The drive control 54 of the continuous braking device 17 depends on the deceleration requirement 41.

[0039] The braking unit 30 of the tractor braking system is configured to detect a deceleration requirement 41 from 58 to the continuous braking system 17. After detecting the deceleration requirement, 56 is monitored to ensure that at least one pre-defined safety criterion 1 or 2 is met based on continuously known braking state parameters 50 and 51. If the pre-defined safety criteria 1 or 2 are met, the unfulfilled portion 52 of the deceleration requirement 41 to the continuous braking system 17 is achieved via the trailer braking system 4. If the safety criteria 1 or 2 are met, the brake control unit 30 implements a restriction 53 on the deceleration to be achieved via the continuous braking system 17. That is, when the restriction 53 occurs on the continuous braking system 17, the control unit 46 of the continuous braking system 17 does not require further deceleration and the unfulfilled portion 52 of the deceleration requirement 41 to the continuous braking system 17 is achieved via the trailer braking system 4. For this purpose, the brake control unit 30 provides a trailer braking pressure PA via a trailer pressure control valve 38, which corresponds to the unfulfilled portion 52 of the deceleration requirement 41.

[0040] One or more critical driving conditions for vehicle combination 7 are pre-defined as a first safety criterion 1. In the illustrated embodiment, multiple critical driving conditions U1, U2, U3, U4, U5, U6, U7, and U8 of the vehicle combination are considered, wherein a specific maximum speed v-max is pre-defined for each of these driving conditions U1, U2, U3, U4, U5, U6, U7, and U8. The critical first driving condition U1 in the illustrated embodiment is or is identified as driving on a curve that is about to begin, particularly driving on a curve of greater degree, such as, for example, at a highway exit or on a serpentine road. Driving on a downhill road that is currently present or identified as about to begin is set as a critical second driving condition U2. Critical driving conditions may also depend on external temperature, such that a specific external temperature, for example, below +3 degrees Celsius, is pre-defined as a critical additional driving condition U3. A slippery driving lane or a driving lane covered by ice or snow is set as a critical additional driving condition U4. Preferably, the axle load of the rear axle 9 of the tractor 5 under continuous braking 17 is also considered as a critical driving condition U5. Here, considering the loading state of the tractor, that is, safety criterion 1 takes into account the relationship between the axle load of the rear axle 9 of the tractor under continuous braking 17 and the maximum permissible axle load of the rear axle 9. The relationship between the mass of the tractor 5 of the vehicle combination 7 and the permissible mass of the tractor 5 is also considered as a critical additional driving condition U6 when the mass of the trailer 6 is relatively high.

[0041] The critical driving conditions are predetermined, especially taking into account the braking power capability of the continuous brake 17. In addition, the driving speed of the vehicle combination 7 at the start of braking is also taken into account when evaluating the driving conditions as critical, and the higher the driving speed of the vehicle combination 7 is, the more critical it is considered for each driving condition.

[0042] The instantaneous driving speed v-ist of vehicle assembly 7 is considered as a continuously known braking state parameter 50, which is used to monitor 56 and evaluate critical driving conditions U1, U2, U3, U4, U5, U6, U7, and U8 of vehicle assembly 7, which are pre-given as the first safety criterion 1.

[0043] The brake slip ratio value v2, representing the wheel slip ratio, of the axle 11 on which the continuous braking system 17 is applied is used as the second braking state parameter 51. In the illustrated embodiment, the axle on which the continuous braking system 17 is applied is the rear axle 9 of the tractor 5. The brake slip ratio value v2 is acquired via a speed sensor 34 on the wheel of the relevant axle. Preferably, the brake slip ratio value v2, considered as the second braking state parameter 51, is provided by the anti-lock braking system 36 of the tractor braking system 3. The brake slip ratio value v2, considered as the second braking state parameter 51, is compared with a slip ratio boundary value 47, which is pre-defined as the second safety criterion 2. If the braking state parameter 51 reaches or exceeds the slip ratio boundary value 47, the deceleration requirement to the continuous braking device 17 is allocated, that is, the current deceleration requirement to the continuous braking device 17 is limited 53, and a trailer braking pressure PA equivalent to the unfulfilled portion 52 of the deceleration requirement 41 to the continuous braking device 17 is provided, so that the unfulfilled portion 52 of the deceleration requirement 41 is achieved via the trailer braking device 4.

[0044] A slip ratio boundary value 47 is pre-defined with a certain gap 48 between the intervention threshold 44 that reacts to the anti-lock braking system 36 of the tractor braking system 3. In this way, it is ensured that the deceleration requirement 41 of the continuous braking system 17 is limited in time before the anti-lock braking system 36 intervenes.

[0045] The brake electronics of the trailer braking system 4 continuously inform the brake control unit 30 of the tractor braking system 3 of the trailer's brake slip ratio value vTr via the communication connection 42 between the tractor 5 and the trailer 6. The brake electronics continuously obtain the brake slip ratio value of the trailer 6 by evaluating the measurement signals from the speed sensors 34 on the wheels of the trailer 6. The brake slip ratio value vTr of the trailer 6 is advantageously obtained by the anti-lock braking system of the trailer 6, particularly by averaging the brake slip ratio values ​​of the individual wheels or axles of the trailer 6.

[0046] The tractor's brake control unit 30 distributes braking force 57 based on the detected brake slip ratio value vTr of the trailer 6 and the brake slip ratio values ​​V1, V2, V3, and V4 of the tractor 5. Corresponding to the braking force distribution 57 to the axles of each vehicle 5, 6 in the tractor braking system 3 and trailer braking system 4, or vehicle combination 7, the brake pressure P within the tractor braking system 3 and the trailer braking pressure PA for the trailer braking system 4 are obtained and provided. By adjusting the brake pressure P and the trailer braking pressure PA, the brake control unit 30 adjusts the pre-given slip ratio difference between the tractor 5 and the trailer 6. Figure 1 (SD in the attached figures).

[0047] If the vehicle assembly 7 has more than one trailer 6, the drive control of the trailer braking system and the adjustment of the slip ratio difference SD are performed in such a way that each trailer 6 within the vehicle assembly 7 has an averaged braking slip ratio value that is greater than or equal to the braking slip ratio value of the trailer 6 that is closer to the tractor 5 in terms of the relevant trailer. The purpose of adjusting the slip ratio difference and distributing braking force here may be to ensure that all parts of the vehicle assembly 7, especially the trailers 6, have the same braking slip ratio value vTr.

[0048] List of icon numbers

[0049] 1. First safety criterion

[0050] 2. Second security criterion

[0051] 3. Tractor braking system

[0052] 4. Trailer braking system

[0053] 5. Tractor

[0054] 6. Trailer

[0055] 7. Vehicle Combination

[0056] 8. Front axle

[0057] 9. Rear axle

[0058] 10. Wheel

[0059] 11. Axle with continuous braking

[0060] 12. Trailer rear axle

[0061] 13. Wheel brakes

[0062] 14. Trailer front axle

[0063] 15. Brake pedal

[0064] 16. Service brake valve

[0065] 17. Continuous braking system

[0066] 18. Signal lines

[0067] 19. Pressure medium accumulator

[0068] 20. Pressure medium accumulator

[0069] 21. First braking circuit

[0070] 22. Second braking circuit

[0071] 23. Coupler

[0072] 24. Trailer control valve

[0073] 25. Pressure medium accumulator

[0074] 26. Trailer Braking Circuit

[0075] 27. Pressure control valve

[0076] 28. Control signals

[0077] 29. Information signals

[0078] 30. Brake control unit

[0079] 31. Braking electronics

[0080] 32. Inlet valve

[0081] 33. Outlet valve

[0082] 34. Speed ​​sensor

[0083] 35. Measurement signal

[0084] 36. Anti-lock braking system

[0085] 37. Synthetic Characteristic Curve Memory

[0086] 38. Trailer pressure control valve

[0087] 39. Service Braking Requirements

[0088] 40. Assessment

[0089] 41. Deceleration requirements of continuous braking system

[0090] 42. Communication Connector (CAN)

[0091] 43. Trailer brake pressure circuit

[0092] 44. ABS Intervention Threshold

[0093] 45. Signal lines

[0094] 46. ​​Control unit for continuous braking system

[0095] 47. Slip ratio boundary values

[0096] 48. Gap

[0097] 49. Control lever for continuous brake

[0098] 50. First braking state parameters

[0099] 51. Second braking state parameters

[0100] 52. Section on deceleration requirements

[0101] 53. Limit the deceleration requirements.

[0102] 54. Control of continuous braking system

[0103] 55. Status information of continuous braking system

[0104] 56. Monitoring

[0105] 57. Braking force distribution

[0106] 58. Detection

[0107] U1 Driving Status

[0108] U2 Driving Status

[0109] U3 Driving Status

[0110] U4 Driving Status

[0111] U5 Driving Status

[0112] U6 Driving Status

[0113] U7 Driving Status

[0114] U8 Driving Status

[0115] Vmax (maximum speed)

[0116] P Braking pressure

[0117] PA trailer brake pressure

[0118] V1 Braking slip ratio value

[0119] V2 Braking Slip Ratio

[0120] V3 Braking Slip Ratio

[0121] V4 Braking Slip Ratio

[0122] vTr is the braking slip ratio value of the trailer.

[0123] SD slip ratio difference

Claims

1. Method for decelerating a vehicle combination (7) having a towing vehicle (5) and at least one trailer (6) having its own trailer brake facility (4), wherein A brake control unit (30) of a tractor brake system (3) monitors the braking behavior of the tractor (5) or of the vehicle combination (7) and sets the respective brake pressure (P) on the wheel brakes (13) of the associated wheels (10) of the tractor (5) and the trailer brake pressure (P-A) as required, wherein the brake control unit (30) detects a driver's manual deceleration request (41) to a service brake system (17) and monitors whether at least one predefined safety criterion (1, 2) is fulfilled during actuation (54) of the service brake system (17) as a function of at least one continuously detected braking state variable (50, 51) and, in the event of fulfillment of the safety criterion (1, 2), causes a yet to be implemented portion (52) of the deceleration request (41) to the service brake system (17) to be implemented via the trailer brake system (4), wherein brake electronics (31) of the trailer brake system (4) detect a brake slip ratio value (vTr) of the wheels (10) of the trailer (6) and inform the brake control unit (30) of the tractor brake system (3) of an information signal (29) with a message about the brake slip ratio value (vTr) of the trailer (6), wherein the brake control unit (30) of the tractor brake system (3) regulates a predefined slip ratio difference (SD) between the tractor (5) and the trailer (6) via the set brake pressure (P) and the trailer brake pressure (P-A).

2. The method of claim 1, wherein, A critical driving situation (Ul, U2, U3, U4, U5, U6, U7, U8) of the vehicle combination (7) and a maximum speed (v-max) set for this driving situation (Ul, U2, U3, U4, U5, U6, U7, U8) are predefined as a first safety criterion (1), and the speed (v-Ist) of the vehicle combination is considered as a first braking state variable (50) and compared with the maximum speed (v-max).

3. The method according to claim 1 or 2, characterized in that, A brake slip ratio value (v2) representative of the wheel slip ratio of the wheels (10) of the axle (11) on which the service brake system (17) acts or an axle-related brake slip ratio value (v2) of this axle (11) is detected as a second braking state variable (51), and the brake slip ratio value (v2) is compared with a slip ratio limit value (47) predefined as a second safety criterion (2).

4. The method of claim 3, wherein, The intervention threshold (44) responsive to the antilock system (36) of the tractor brake system (3) has the slip ratio limit value (47) predefined with a certain margin (48).

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