DE102018220164A1 - Method for operating a coupled vehicle convoy - Google Patents

Abstract

The invention relates to a method for operating a vehicle convoy (10) which has two vehicles (2, 4) that can be driven with a respective internal combustion engine (7). The vehicles are coupled to one another via a mechanical coupling device (3). The method specifies an engine operating state for one of the mechanically coupled vehicles (2) of the vehicle convoy (10). In the method, a force is also transmitted from one vehicle (2) of the mechanically coupled vehicles to the other vehicle (4) of the mechanically coupled vehicles (2, 4) via the mechanical coupling device (3) in order to bring about the predetermined engine operating state. The invention also relates to a control system for performing the method.

Description

Technical field

The present invention relates to a method for operating a vehicle convoy which has two vehicles which can be driven by an internal combustion engine. Furthermore, the present invention relates to a control system which is set up to carry out such a method.

State of the art

It is known that vehicles can be mechanically coupled to one another in road traffic. In the US 2011/0270520 A1 For example, a train consisting of mechanically coupled commercial vehicles is described. Furthermore goes from the WO 2016/041979 A1 a train from mechanically coupled passenger vehicles.

Presentation of the invention

The present invention relates to a method for operating a vehicle convoy which has two vehicles which can be driven by a respective internal combustion engine. The vehicle convoy can have a network of at least two vehicles coupled in pairs. The vehicles in the vehicle convoy can be commercial vehicles or passenger vehicles. For example, a tractor-trailer can be provided as a commercial vehicle. However, other vehicles are also conceivable here. The vehicles of the vehicle convoy are coupled to one another via a mechanical coupling device. The coupling device can be designed such that driving forces can be transmitted from a leading vehicle of the vehicle convoy to a following vehicle of the vehicle convoy or vice versa.

The method comprises specifying an engine operating state for one of the mechanically coupled vehicles of the vehicle convoy. The engine operating state may include a range, a curve section or an interval of engine operating points in a consumption map of the internal combustion engine of the mechanically coupled vehicle. For example, the engine operating condition is a partial load range of the engine. It is also conceivable that the engine operating state is a full load range or another operating range. The engine operating condition may also be a single engine operating point from an internal combustion engine. The predetermined engine operating state can be a target operating state of the internal combustion engine in which the internal combustion engine can operate in a specific efficiency range. Such an efficiency range can enable the internal combustion engine to be operated at high to optimal fuel efficiency.

The method also has a transmission of a force from one vehicle of the mechanically coupled vehicles to the other vehicle of the mechanically coupled vehicles via the mechanical coupling device in order to bring about the predetermined engine operating state. An actual operating state of the internal combustion engine can essentially change into the predetermined target operating state by the transmitted force. The bringing about of the engine operating state can have a shifting of a current engine operating point in the consumption map of the internal combustion engine, wherein the shifting can be a raising or lowering of the current engine operating point. The engine operating state can be specified or brought about as a function of a transmission gear of the vehicle. With such a power transmission, a corresponding load point shift and thus a reduction in the specific fuel consumption of an internal combustion engine can be achieved.

Within the scope of the invention, cross-vehicle energy management can thus be carried out by means of a targeted power transmission by means of a mechanical coupling between two convoy vehicles. The energy management can include a power distribution among the internal combustion engines of the vehicles in order to be able to operate the entire vehicle convoy in a more fuel-efficient manner. In other words, the energy management can include a load distribution over the internal combustion engines of the vehicles. The mechanical coupling between the vehicles can therefore not only be used to reduce air resistance by reducing the vehicle distance, but also specifically for consumption-optimized engine operating point control. Since, for example, the air resistance of the vehicle in front in the vehicle convoy cannot be significantly reduced by slipstream driving, an engine operating point control according to the invention enables fuel efficiency to be optimized across all vehicles in the vehicle convoy.

The mechanical coupling can have a coupling mechanism, which can enable automatic coupling of the vehicles while driving. For this purpose, the mechanical coupling can have a sensor with which an automatic coupling process can be controlled. A vehicle distance from mechanically coupled vehicles can be, for example, one to two meters. An advantage of mechanical coupling can be seen in the fact that collisions within the vehicle convoy can already be prevented by the coupling as such. Rear-end collisions caused by the vehicle convoy can also be prevented by optimizing the braking distance of the coupled convoy. Further advantages can be seen in the fact that the driver of a following vehicle can be able to take a break in the vehicle. It is conceivable that this rest period is not added to the driver's driving time. The security felt by a driver of the following vehicle during such a break can be increased by the presence of the mechanical coupling. Longer breaks are also made possible by a vehicle-level route agreement.

Coupled vehicles of the vehicle convoy can swap their positions within the convoy, whereby a following vehicle can become a preceding vehicle and vice versa. The power transmission or an engine operating point control can then be carried out in the reverse manner. In this way, vehicle convoys can cover longer distances in one continuous journey, with drivers in a vehicle that is currently driving in front during a driving time and drivers in a vehicle that is currently following in a rest period. The parking of vehicles can be reduced to a minimum.

An embodiment of the method can have a predefined engine operating state for the two mechanically coupled vehicles of the vehicle convoy. The specification of the engine operating states can be based on a respective efficiency of the internal combustion engines of the two vehicles. Taking into account the respective efficiencies, the mechanically coupled vehicles can thus be operated in such a way that the specific fuel consumption of their internal combustion engines can be reduced when viewed together.

The embodiment further comprises transmitting a force from one vehicle of the mechanically coupled vehicles to the other vehicle of the mechanically coupled vehicles via the mechanical coupling device in order to bring about the predetermined engine operating states. An actual operating state of the two internal combustion engines can thus essentially change into a respective predetermined target operating state through the power transmission. With such a power transmission, a corresponding load distribution and thus a reduction in the specific fuel consumption over the entire vehicle convoy can be achieved.

The mechanical coupling device can be designed to transmit longitudinal forces, that is to say essentially forces in the direction of travel of the vehicle convoy, across vehicles. In a further embodiment of the method, the transmission of a force via the mechanical coupling device comprises a transmission of a tensile force from the preceding vehicle of the mechanically coupled vehicles to the following vehicle of the mechanically coupled vehicles. The pulling force can result from the following vehicle being pulled by the vehicle in front. The vehicle in front or its internal combustion engine can thus do a main work for moving the mechanically coupled vehicles. The following vehicle or its internal combustion engine can also perform additional work for moving the mechanically coupled vehicles. The internal combustion engine of the vehicle in front can be cooled more efficiently than the internal combustion engine of the vehicle behind by free air inflow. Accordingly, it can be advantageous to perform the main work or performance for moving the entire convoy by the vehicle in front.

In a further embodiment of the method, the following vehicle has a hybrid drive with an internal combustion engine and an electric motor. In principle, all vehicles in the vehicle convoy can have such a hybrid drive. If a tractive force is transmitted from the preceding vehicle to the following vehicle via the mechanical coupling device, the internal combustion engine of the following vehicle can be switched off. The shutdown can take place taking into account a power requirement of an air conditioning system, a heater and / or a fan of the vehicle. In the context of the embodiment, the following mechanically coupled vehicle can be driven by the electric motor. In particular, the following vehicle can only be driven by the electric motor. In this way, pollutant emissions from the following vehicle can be minimized.

In a further embodiment of the method, the transmission of a force via the mechanical coupling device has a transmission of a pushing force from the following vehicle to the preceding vehicle. The pushing force can also be understood as a pushing force, the following vehicle transmitting the pushing force to the vehicle in front via the mechanical coupling device. The pushing force can result from a pushing of the vehicle in front by the following vehicle. The following vehicle or its internal combustion engine can do a major job of moving the mechanically coupled vehicles. The vehicle in front or its internal combustion engine can also carry out additional work.

In a further embodiment of the method, the vehicle in front has a generator and an energy store. The embodiment comprises generating energy with the generator and supplying the generated energy to the energy store based on the transmitted pushing force. For this purpose, the electric motor can act as an electromotive brake and thus feed electrical energy into an accumulator of the vehicle. For example, the vehicle convoy can be braked wear-free when driving downhill. Likewise, the recuperation of the electric motor can be set so that the internal combustion engine (s) of the vehicle convoy are operated at an optimized engine operating point. All vehicles in the convoy can have such a generator and / or energy store.

Another embodiment of the method comprises determining a current driving resistance of a vehicle whose engine operating state is specified. The specification of the engine operating state for the vehicle can then be based on the determined driving resistance of the vehicle. The specification of the engine operating state for the vehicle can be based, for example, on an air resistance, a rolling resistance, a gradient resistance and / or an acceleration resistance. The engine operating state can be dynamically adapted to a changing driving resistance while the vehicle convoy is traveling. Thus, for example, a topography of a route to be traveled can be taken into account in the engine operating point control. Depending on a current driving resistance, the load distribution to the drive units of the convoy vehicles can be controlled in such a way that the motors are operated in a working area that is optimized with regard to ambient conditions.

In addition to the transmission of longitudinal forces, the mechanical coupling device can also be designed to transmit lateral forces from a leading vehicle of the vehicle convoy to a following vehicle of the vehicle convoy or vice versa. In a further embodiment of the method, the transmission of a force via the mechanical coupling device has a transmission of a steering force from the preceding vehicle to the following vehicle in order to steer the following vehicle. When steering the vehicle in front, a resulting drag curve of the vehicle convoy can be taken into account for the steering. In addition to the power transmission, the mechanical coupling device can thus be used as a mechanical drawbar for steering the following vehicle. The following vehicle can advantageously be passively steered and follow the vehicle in front as a driverless vehicle if the steering is enabled.

Another embodiment of the method comprises determining a force currently applied to the mechanical coupling device with a force measuring device. For this purpose, the force measuring device can be arranged on the mechanical coupling device. The force measuring device can have any sensor which is suitable for directly or indirectly determining a force in the longitudinal direction of the mechanical coupling device. For example, the sensor can have a load cell or a strain gauge. The sensor can be a safety sensor which is independent of the control of the power transmission and which can be used to determine and transmit longitudinal dynamic information of the preceding vehicle to the following vehicle.

The embodiment has a control of the longitudinal dynamics of the preceding vehicle and / or the following vehicle of the mechanically coupled vehicles based on the determined force. For example, a force acting on the mechanical coupling device by braking or accelerating one of the mechanically coupled vehicles can be detected. A detected braking or acceleration request can be transmitted to the other of the mechanically coupled vehicles. If a radio link between the mechanically coupled vehicles is disrupted, a braking maneuver initiated by the preceding vehicle can be recognized by the force measuring device, for example. Braking of the following vehicle can be initiated based on the measured force. In this way, the safety of the vehicle convoy can be increased and a braking distance of the vehicle convoy, for example in the event of emergency braking, can be advantageously reduced.

The invention further relates to a control system which is set up to carry out the method according to one of the previously described embodiments. The control system has a control device for each vehicle of the vehicle convoy, which is set up to carry out the method steps. Each of the control devices can interface with the respective internal combustion engine, electric motor and / or the respective brake of the vehicle get connected. The respective control devices can also be set up to communicate with one another. With regard to the understanding and the advantages of the individual features, reference is made to the above statements.

Figure list

• 1 schematically shows a coupled vehicle convoy in a plan view to explain the method and the control system for operating a vehicle convoy according to an embodiment of the present invention.
• 2nd shows a flow chart with steps of a method for operating a vehicle convoy according to an embodiment of the present invention.

Detailed description of embodiments

In 1 is a vehicle convoy 10th with two vehicles in a row 2nd , 4th shown. The two vehicles 2nd , 4th are with a mechanical coupling device 3rd coupled together. The vehicle in front 2nd is with the mechanical coupling device 3rd via a swiveling coupling joint 9 in the rear of the vehicle in front 2nd articulated. The following vehicle 4th is with the mechanical coupling device 3rd via another swiveling coupling joint 9 in the front area of the following vehicle 4th articulated.

In addition to an internal combustion engine 7 is on each of the vehicles 2nd , 4th an electric motor 8th intended. The vehicles 2nd , 4th each have a hybrid drive, which the respective internal combustion engine 7 and the respective electric motor 8th includes. The internal combustion engine 7 and the electric motor 8th are on the respective vehicle 2nd , 4th with a control device 6 connected.

On the mechanical coupling device 3rd is also a force measuring device 5 arranged, which on the mechanical coupling device 3rd applied traction Z measures. The measured traction Z is sent to the control facilities 6 with a data connection, not shown, transmitted to the motors 7 , 8th to control based on the current force. In addition, brake systems of the vehicles are not shown 2nd , 4th from the control devices 6 controllable. The control devices 6 of vehicles 2nd , 4th of the convoy 10th are coupled to each other via a wireless connection in the present embodiment.

The vehicle in front 2nd exerts a tensile force in the present embodiment Z via the mechanical coupling device 3rd on the following vehicle 4th out. The internal combustion engine 7 of the vehicle in front 2nd does the main work for moving the vehicle in front 2nd and the following vehicle 4th formed team. The internal combustion engine 7 of the following vehicle 4th works in parallel.

In 2nd are steps S1 , S2 a method for operating the in 1 shown vehicle convoys 10th shown in a time sequence according to an embodiment of the present invention. In a first step S1 an operating state of the internal combustion engine is specified 7 for the vehicle in front 2nd the one with the mechanical coupling device 3rd coupled vehicles 2nd , 4th . The predefined operating state is, for example, a partial load range of the internal combustion engine 7 . The specified operating state is sent to the control devices 6 of both vehicles 2nd , 4th of the convoy communicates.

In a second step S2 become the operating points of the internal combustion engines 7 and electric motors 8th of the two vehicles 2nd , 4th through their control facilities 6 each set so that the specified operating state of the vehicle in front 2nd is achieved. Accordingly, in the present embodiment, the motors are controlled so that the internal combustion engine 7 of the vehicle in front is operated in the partial load range. For this there is, for example, a power transmission from the preceding vehicle 2nd on the following vehicle 4th via the mechanical coupling device 3rd with the traction exerted Z required. By increasing the load on the internal combustion engine 7 of the vehicle in front 2nd becomes the internal combustion engine 7 in the step S1 specified partial load range operated. The following vehicle 4th can in this state, for example, only by means of the electric motor 8th are driven. During operation, the traction Z with the force measuring device 5 be monitored. If this exceeds a threshold value, the control devices can 6 the operations of the individual engines 7 , 8th of vehicles 2nd , 4th adjust accordingly.

Reference symbol list

2nd

vehicle in front

3rd

mechanical coupling device

4th

following vehicle

5

Force measuring device

6

Control device

7

Internal combustion engine

8th

Electric motor

9

Coupling joint

10th

Vehicle convoy

S1

Specification of engine operating status

S2

Power transmission

Z

traction

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 2011/0270520 A1 [0002]
• WO 2016/041979 A1 [0002]

Claims (10)

Method for operating a vehicle convoy (10) which has two vehicles (2, 4) which can be driven with a respective internal combustion engine (7) and which are coupled to one another via a mechanical coupling device (3), with the steps of specifying (S1) an engine operating state for one the mechanically coupled vehicles (2) of the vehicle convoy (10); and transmitting (S2) a force from one vehicle (2) of the mechanically coupled vehicles to the other vehicle (4) of the mechanically coupled vehicles (2, 4) via the mechanical coupling device (3) in order to bring about the predetermined engine operating state. Procedure according to Claim 1 , with the steps of specifying (S1) a respective engine operating state for the two mechanically coupled vehicles (2, 4) of the vehicle convoy (10) based on a respective efficiency of the internal combustion engines (7) of the two vehicles (2, 4); and transmitting (S2) a force from one vehicle (2) of the mechanically coupled vehicles to the other vehicle (4) of the mechanically coupled vehicles via the mechanical coupling device (3) in order to bring about the predetermined engine operating states. Procedure according to Claim 1 or 2nd The step of transmitting (S2) a force comprises transmitting a tensile force (Z) from the preceding vehicle (2) of the mechanically coupled vehicles (2, 4) to the following vehicle (4) of the mechanically coupled vehicles (2, 4) . Procedure according to Claim 3 The following vehicle (4) has a hybrid drive with an electric motor (8) and the method further comprises driving the subsequent mechanically coupled vehicle (4) with the electric motor (8). Method according to one of the preceding claims, wherein the step of transmitting (S2) a force Transmission of a pushing force from the following vehicle (4) of the mechanically coupled vehicles (2, 4) to the preceding vehicle (2) of the mechanically coupled vehicles (2, 4). Procedure according to Claim 5 , wherein the preceding vehicle (2) has a generator and an energy store and the method further comprises generating energy with the generator and supplying the generated energy to the energy store based on the transmitted pushing force. Method according to one of the preceding claims, with the step Determining a current driving resistance of a vehicle (2) of the vehicle convoy (10); and Specifying (S1) the engine operating state based on the determined driving resistance of the vehicle (2). Method according to one of the preceding claims, wherein the step of transmitting (S2) a force Transmission of a steering force from the preceding vehicle (2) of the mechanically coupled vehicles (2, 4) to the following vehicle (4) of the mechanically coupled vehicles (2, 4) in order to steer the following vehicle (4). Method according to one of the preceding claims, comprising the steps of determining a force currently applied to the mechanical coupling device (3) with a force measuring device (5) which is arranged on the mechanical coupling device (3); and controlling the longitudinal dynamics of the preceding vehicle (2) and / or the following vehicle (4) of the mechanically coupled vehicles (2, 4) based on the determined force. Control system which is set up to carry out the method according to one of the preceding claims, comprising a control device (6) for each of the two vehicles (2, 4) of the vehicle convoy (10).

Images