Method for slowing down a consist
By first increasing the braking force of the traction vehicle in the trainset and utilizing the rapid response of the electronic control system, the problem of slow deceleration of the trainset was solved, achieving faster deceleration response and maintaining a safe distance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZF CV SYST GLOBAL GMBH
- Filing Date
- 2024-11-14
- Publication Date
- 2026-06-16
AI Technical Summary
In the existing technology, the deceleration process of the train set is usually not fast enough, especially when the pneumatic signal is transmitted between the tractor and the trailer, which results in the unsatisfactory deceleration being achieved.
Upon receiving the desired deceleration, the braking force of the tractor vehicle is first set to a level higher than the braking force distribution. The rapid response of the electronic control system is used to temporarily increase the braking force of the tractor vehicle. Once the trailer braking system responds, the braking force distribution is adjusted to restore balance.
The fast-response traction vehicle braking system significantly shortens the trainset's reaction time to deceleration, ensures a safe distance, and maintains a constant total braking force while the trailer braking system responds.
Smart Images
Figure CN122228200A_ABST
Abstract
Description
Technical Field
[0001] According to claim 1, the present invention relates to a method for decelerating a trainset having a tractor vehicle and at least one trailer vehicle, wherein the braking control unit of the tractor vehicle calculates the total braking force upon receiving a desired deceleration, the total braking force being applied jointly by the trailer braking device and the tractor vehicle braking device. Background Technology
[0002] In commercial vehicles, wheels are typically braked via pneumatically operated wheel brakes, where each sub-vehicle in the vehicle group has its own braking system. Electronic or automated braking systems are increasingly used, where wheel brakes are actuated via electronic control of the brake actuators (rather than a mechanical connection between the brake pedal and the wheel brakes). The brake pedal is the operating device by which the driver communicates their desired deceleration. The identification of the desired deceleration by means of a pedal travel sensor and its transmission via electronic signal lines is also known as "brake-by-wire." In the vehicle group, the tractor's brake control unit receives the desired deceleration and determines the braking force distribution to be applied by the tractor's and trailer's brake systems to optimally achieve the desired deceleration. The tractor's brake control unit then operates the tractor's brake system and, in addition, causes the trailer's brake system to generate a portion of the braking force for the trailer vehicle.
[0003] The advantage of electronically controlled deceleration (“brake-by-wire”) is that the vehicle’s wheel brakes respond relatively quickly.
[0004] Document DE44 38 353 C2 discloses a method for electronically controlling or regulating the braking equipment of a trainset, wherein a tractor vehicle that can be coupled to a trailer has electronically regulated or controlled braking equipment. In known methods, braking signals for the tractor vehicle and for the trailer are generated based on the driver's braking expectations to control their braking equipment. Depending on the design of the braking equipment, known methods use different physical quantities as braking signals. The braking signals are transmitted to the trailer vehicle pneumatically or electrically. The pneumatic braking signal is the trailer braking pressure, which is calculated by the braking control unit of the tractor vehicle and provided at the coupling for the trailer braking equipment. For electric brakes, the braking signal may be a target current supplied to the wheel brakes.
[0005] However, it has been found that the desired deceleration is often not achieved quickly enough for train sets, especially when signals are pneumatically transmitted between the tractor and trailer. Summary of the Invention
[0006] The purpose of this invention is to improve this type of method for decelerating train sets so that the desired deceleration is achieved more quickly.
[0007] According to the present invention, the objective is achieved by a method having the features of claim 1.
[0008] This invention is based on the understanding that, for a trainset, if the trailer braking devices of the corresponding connected trailer vehicles are not electronically controlled and therefore the wheel brakes of the trailer vehicles respond significantly slower to deceleration commands, the advantages of electronic deceleration control (“brake-by-wire”) can be utilized only minimally. This invention specifies that, in the first braking phase after receiving the desired deceleration, the tractor vehicle's braking force is initially set to a higher level than set according to the braking force distribution. The brake control unit electrically operates the valves of the tractor vehicle's braking devices to apply a greater braking force than actually set according to the distribution of the total braking force to the partial braking force of the two braking devices. The fast-responding wheel brakes of the tractor vehicle's braking devices can then generate a large trainset deceleration in the first braking phase (when the trailer braking devices have not yet participated in applying the total braking force (the sum of the partial braking forces of the two braking devices)).
[0009] A temporary increase in the braking force of a tractor vehicle with an electronically controlled braking system can be easily achieved by having the tractor vehicle's braking control unit provide trailer braking pressure to the trailer braking equipment and setting the trailer braking pressure according to the partial braking force set for the trailer vehicle. The partial braking force of the fast-response electronic braking system is set to be greater than the braking force level set by the braking force distribution.
[0010] The reaction time of the trainset to the requested deceleration is significantly reduced by first using the tractor braking system with a higher degree of responsiveness, especially for trainsets combined with conventional trailer braking systems. Furthermore, the braking displacement of the trainset is also shortened to reliably maintain a safe distance from vehicles ahead.
[0011] In a preferred embodiment of the invention, the tractor braking device is manipulated during the first braking phase to provide total braking force corresponding to the desired deceleration. Thus, the requested desired deceleration is established very quickly, temporarily only by means of the fast-response wheel brakes of the electronically controlled tractor braking device, as long as the relatively slow-responding trailer braking device has not yet engaged.
[0012] Once the trailer braking system decelerates, the first braking phase ends. During the further deceleration process, the brake control unit 9 reduces the greater deceleration request to the tractor vehicle's braking system according to the invention, thereby restoring balance to the braking force distribution between the tractor vehicle and the trailer vehicle. In this preferred design, after the trailer braking system decelerates, during the transition phase, taking into account the current trailer braking force, the initially large braking force of the tractor vehicle's braking system in the first braking phase is reduced to the set level of the tractor vehicle's braking force. In this way, it is ensured that the train's braking system applies a substantially constant total braking force during the establishment of trailer braking force.
[0013] The occurrence of deceleration effect of the trailer braking system, i.e., the deceleration effect of the braking force of the trailer braking system on the vehicle assembly, is confirmed or assumed to occur in an advantageous embodiment of the invention. In a preferred embodiment of the invention, the occurrence of deceleration effect of the trailer braking system is estimated by measuring the braking time as a predictor variable and evaluating the braking time with preset parameterization. Here, the braking time corresponds to the duration up to the first braking phase, in which the braking force of the tractor vehicle is controlled to a higher braking force level than set according to the braking force distribution. Here, the start of the braking time measurement may be associated with the time point of controlling the trailer braking pressure, or it may have been associated with the receipt of the desired deceleration. When the preset braking time is reached, the deceleration effect of the trailer braking system is assumed to occur.
[0014] In another embodiment of the invention, a predictive variable for monitoring the deceleration effect of the trailer braking system is introduced via a coupling force sensor. Here, the coupling force sensor detects the force between the towing vehicle and the towed trailer, wherein the change in coupling force leads to a conclusion regarding the deceleration effect of the trailer braking system. When a specific coupling force is detected, it is assumed that deceleration of the trailer braking system has occurred.
[0015] In another embodiment, the predictive variable for monitoring the deceleration effect of the trailer braking system is derived from an assessment of the deceleration of the tractor vehicle, which can be measured using an acceleration sensor. Knowing the current braking force of the tractor vehicle, it can be concluded whether the measured deceleration of the tractor vehicle has been achieved under the combined action of the trailer braking force, and therefore whether the deceleration effect of the trailer braking system can be confirmed.
[0016] In the case of a saddle-type tractor, the deceleration effect of the trailer braking system can be confirmed by assessing the change in axle load at at least one axle. Here, the axle load is measured as a predictive variable for monitoring the occurrence of deceleration effect of the trailer braking system. Attached Figure Description
[0017] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. The drawings show:
[0018] Figure 1 This is a pneumatic and electrical schematic diagram of an embodiment of a train braking system combination.
[0019] Figure 2 It is based on Figure 1 A flowchart of an embodiment of a method for decelerating a train set.
[0020] Figure 3 This is a diagram illustrating the time progression of partial braking force during deceleration. Detailed Implementation
[0021] Figure 1 An electro-pneumatic diagram of the combination of pneumatic braking devices 1 and 2 of the commercial vehicles 3 and 4 (i.e., the tractor vehicle 3 and the trailer vehicle 4 in this embodiment) of vehicle group 5 is shown. Electrical lines are represented by solid lines, and pneumatic lines are represented by dashed lines. To brake the wheels 6, each wheel 6 is associated with a wheel brake 7, which can be pneumatically operated via a brake cylinder 8. The wheel brake 7 applies braking force to the rotating wheels 6 according to the pneumatic braking pressure applied in the brake cylinder 8, thereby decelerating vehicle group 5. Braking pressure P acts on the wheel brake 7 of the tractor vehicle braking device 1, and the braking pressure is electronically controlled by the brake control unit 9. Trailer braking pressure PA acts in the trailer braking device 2, and in the illustrated embodiment, the trailer braking pressure is provided and set by the brake control unit 9 of the tractor vehicle 3.
[0022] A brake pedal 10 is installed in the cab of the tractor vehicle 3. The position of the brake pedal is detected by a brake signal transmitter 11 connected to the brake control unit 9. The driver of the tractor vehicle 3 can preset the desired deceleration z-Soll to the brake control unit 9 by operating the brake pedal 10.
[0023] In the illustrated embodiment, the multiple wheel brakes 7 of the front axle 12 of the traction vehicle are associated with a common first brake circuit 13 of an electronically controlled traction vehicle braking device 1, while the multiple wheel brakes 7 of the rear axle 14 can be operated via a second brake circuit 15. Here, a first pressure medium reservoir 16 is associated with the first brake circuit 13, and the second brake circuit 15 of the rear axle 14 is supplied with pressure medium via a second pressure medium reservoir 17.
[0024] The tractor braking device 1 includes a pneumatic coupling 18 to which the trailer braking device 2 of the trailer vehicle 4 can be coupled. The tractor braking device 1 provides a pneumatic trailer braking pressure PA to the trailer braking device 2 via the coupling 18. Here, a trailer control valve 19 is associated with the coupling 18, which governs the connection between the third pressure medium reservoir 20 and the pneumatic coupling 18. The trailer braking device 1 has a trailer braking circuit 21 in which the trailer braking pressure PA provided by the tractor vehicle 1 is present and can be connected to all wheel brakes 7. The brake control unit 9 of the tractor braking device 1 causes the trailer braking device 2 to generate trailer braking force by setting and providing the trailer braking pressure PA.
[0025] A pressure control valve 22, which can be electrically operated, is connected upstream of each brake cylinder 8. To receive control signals, the pressure control valve 22 of the traction vehicle braking device 1 is connected to a brake control unit 9, which influences the braking pressure P through corresponding control signals. Here, the rotational behavior of the wheels 6 is also monitored. Each wheel 6 is associated with a speed sensor 24, which generates a measurement signal containing a statement about the rotational behavior of the corresponding wheel 6. The brake control unit 9 uses the measurement signals from the speed sensor 24 to determine information about the slippage of the corresponding wheel 6.
[0026] Trailer 4 has an anti-lock braking system with braking electronics 23, which is configured to operate a pressure control valve 22 at the brake cylinder of the trailer braking device 2 and intervene under the action of trailer braking pressure PA when a wheel has a tendency to lock up during braking. Braking electronics 23 monitors the slippage of each wheel via a speed sensor 24, which occurs when the brakes are applied. Here, the braking force to be applied is pneumatically determined by the braking control unit 9 of the tractor vehicle via the already provided trailer braking pressure PA. Upon confirming a tendency to lock up a single wheel, braking electronics 23 counteracts the lockup of the wheel involved by operating one or more pressure control valves 22 and adjusting the braking pressure along the slip limit.
[0027] Figure 2The flowchart illustrates an embodiment of a method for decelerating vehicle group 5 after the driver presets a desired deceleration z-Soll to the brake control unit by manipulating the brake pedal and the brake signal transmitter 11 connected to the brake pedal. After determining the total braking force FBges for achieving the desired deceleration z-Soll, the brake control unit determines the braking force distribution 28 for the total braking force FBges, namely, the braking force level of the tractor braking force FBZ to be applied by the tractor braking device 1 as part of the total braking force FBges, and the braking force level of the trailer braking force FBA to be applied by the trailer vehicle. Based on the partial braking force FBA set for the trailer vehicle, the brake control unit provides trailer braking pressure, and thus causes the trailer braking device 2 to achieve the trailer braking force FBA. Taking into account the trailer braking force FBA, the tractor braking force FBZ is set 29, which should ultimately reach the braking force level FBZ2 according to the braking force distribution 28. The brake control unit accordingly operates the wheel brakes of the tractor braking device 1.
[0028] Electronically controlled tractor braking systems respond faster than trailer braking systems that are pneumatically responsive via trailer brake pressure PA and controlled by the tractor's brake control unit 9. The time progression of partial braking forces FBZ and FBA is... Figure 3 As shown in the diagram, although the electronically controlled tractor braking system 1 begins to establish the tractor braking force FBZ at time t1, the trailer braking system 2's braking response occurs at time t2. It is not until time t3 that the trailer braking force FBA, which is activated by the trailer braking system, reaches the required braking force distribution 28. Figure 2 The braking force level FBA1 is determined.
[0029] To achieve the desired deceleration z-Soll as quickly as possible, the brake control unit, immediately after receiving the desired deceleration z-Soll, sets the traction vehicle braking force to a higher level FBZ1 than that set according to the braking force distribution 28 during the first braking phase 30. Accordingly, the brake control unit manipulates the traction vehicle braking device to apply a greater braking force than a portion of the braking force set according to the braking force distribution 28. In the illustrated embodiment, the traction vehicle braking force FBZ is set to an increased braking force level FBZ1 during the first braking phase 30, which corresponds to the requested total braking force FBges.
[0030] The first braking phase 30 ends once the deceleration effect of the trailer braking system occurs or is assumed to occur. According to... Figure 3 In the graphical process of partial braking force, the first braking phase continues until the active action of trailer braking device 2 occurs or is assumed to occur at time point t2.
[0031] The brake control unit 9 is configured to monitor whether the trailer brake device 2 and its slower braking response have been engaged and actively participate in the deceleration of the trainset 5 at the beginning of the deceleration process. Here, during the first braking phase 30, the deceleration action 31 of the trailer brake device 2 is monitored 26, and the first braking phase 30 ends once the deceleration action 31 occurs or can be assumed to occur.
[0032] After the deceleration action 31 of the trailer braking device is confirmed or assumed to occur at time point t2, the initial larger tractor braking force FBZ of the tractor braking device 1 starts from the higher braking force level FBZ1 corresponding to the total braking force FBges. During the transition phase 32 until time point t3 (when the trailer braking force FBA reaches the set braking force level FBA1), the braking force decreases to the set braking force level FBZ2, taking into account the current trailer braking force FBA. During the transition phase 32, while the partial braking force of the trailer braking device continues to increase to the set braking force level FBA1 due to the applied trailer braking pressure, the electrical braking request to the electronically controlled tractor braking device is conversely canceled, so that the sum of the two partial braking forces, namely the sum of the tractor braking force FBZ and the trailer braking force FBA, always produces the desired total braking force FBges.
[0033] The occurrence of deceleration 31 is confirmed or assumed based on the evaluation of the measured predictor variable 33. Here, deceleration 31 can be confirmed if the variable that changes with the occurrence of deceleration from the trailer braking device is measured and evaluated as predictor variable 33. This could be an evaluation of the coupling force as a predictor variable, detected by a coupling force sensor. Another feasible approach to obtain expected information about the occurrence of deceleration and, consequently, the end of the first braking phase, is to evaluate the measured deceleration of the tractor vehicle as a predictor variable. For saddle-type tractors, the change in axle load at one or more axles can be measured as a predictor variable containing information about the occurrence of deceleration.
[0034] In the illustrated embodiment, the deceleration effect 31 of the trailer brake device 26 is indirectly monitored by evaluating the braking time t, which is a predictor variable 33. It is assumed that deceleration of the trailer brake device occurs when a specific braking time t2 is reached. The braking time t2 (at which the trailer braking force FBA is assumed to be engaged) is a preset 25, wherein the parameters used to determine the preset are empirically determined. In the illustrated embodiment, the brake control unit of the electronic braking system associates the start of the measurement of braking time t2 with the pneumatic actuation of the trailer braking force FBA by providing trailer braking pressure. List of reference numerals in the attached diagram: 1. Braking equipment for traction vehicles 2. Trailer braking equipment 3. Towing vehicles 4. Trailer vehicles 5 train sets 6 wheels 7. Wheel brakes 8 Brake cylinders 9. Brake Control Unit 10. Brake pedal 11 Braking signal transmitter 12 front axles 13 First Braking Circuit 14 Rear Axle 15 Second Braking Circuit 16 First pressure medium storage tank 17 Second pressure medium storage tank 18 Connector 19 Trailer control valve 20 Third pressure medium storage tank 21 Trailer Braking Circuit 22 Pressure control valve 23 Braking Electronic Devices 24 Speed sensor 25 Presets 26 Monitoring 27. Find the total deceleration. 28. Braking force distribution 29. Set braking force 30 First Braking Stage 31. Effective 32 Transition Phase 33 Predictors P Braking pressure PA trailer brake pressure z-Soll expected deceleration t Braking time t1 time point t2 time point t3 time point FBZ traction vehicle braking force FBA Trailer Braking FBZ1 has a high level of braking force. FBZ2 Braking force level based on braking force distribution FBA1 Braking Force Level FBges Total braking force.
Claims
1. A method for decelerating a trainset (5) having a tractor (3) and at least one trailer (4), wherein, The braking control unit (9) of the tractor vehicle (3) calculates the total braking force (FBges) when it receives the desired deceleration (z-Soll). The total braking force is applied jointly by the trailer braking device (2) and the tractor vehicle braking device (1) in a braking force distribution (28). The braking control unit (9) causes the trailer braking device (2) to apply the trailer braking force (FBA) and determines the tractor vehicle braking force (FBZ) in consideration of the currently applied trailer braking force (FBA) and sets the tractor vehicle braking force by manipulating the tractor vehicle braking device (1). The characteristic is that in the first braking phase (30) after receiving the desired deceleration (z-Soll), the tractor vehicle braking force (FBZ) is first set to a higher braking force level (FBZ1) than that set according to the braking force distribution (28).
2. The method according to claim 1, characterized in that, During the first braking phase (30), the traction vehicle braking force (FBZ) is set to a braking force level (FBZ1) corresponding to the total braking force (FBges), and the traction vehicle braking device (1) is operated accordingly.
3. The method according to claim 1 or 2, characterized in that, During the first braking phase (30), the deceleration effect (31) of the trailer braking device (2) is monitored (26), and the first braking phase (30) ends once the deceleration effect (31) occurs or is assumed to occur.
4. The method according to claim 3, characterized in that, The deceleration effect (31) of the trailer braking device (2) is indirectly monitored (26) via the measured predictor variable (33).
5. The method according to any one of the preceding claims, characterized in that, After the deceleration action (31) of the trailer braking device (2) is confirmed or assumed to occur, the initial large tractor braking force (FBZ) of the tractor braking device (1) is reduced during the transition phase (32) to the tractor braking force (FBZ) level (FBZ2) set according to the braking force distribution (28), taking into account the trailer braking force (FBA) currently in effect.
6. A braking control unit (9) for a tractor (3) in a vehicle group (5) having a tractor (3) and at least one trailer (4), wherein, The braking control unit (9) is configured to determine the total braking force (FBges) upon receiving a desired deceleration (z-Soll), the total braking force being jointly applied by the trailer braking device (2) and the tractor braking device (1) in a manner of braking force distribution (28), wherein the braking control unit (9) is configured to cause the trailer braking device (2) to apply trailer braking force (FBA), and to determine the tractor braking force (FBZ) in consideration of the currently applied trailer braking force (FBA) and to set the tractor braking force by manipulating the tractor braking device (1), characterized in that the braking control unit (9) is configured to, in the first braking phase (30) after receiving the desired deceleration (z-Soll), first set the tractor braking force (FBZ) to a higher braking force level (FBZ1) than that set according to the braking force distribution (28).
Citation Information
Patent Citations
Device for winding vertically arranged material strip, e.g. for advertising material, film screen etc.
DE4438353A1