EP3406799B1 - Machine train consisting of a road milling machine and a paver and method for operating a road milling machine and a paver - Google Patents

Description

The invention relates to a machine train comprising a road milling machine in front which has a machine frame carried by chain drives or wheels and a milling drum arranged on the machine frame for milling off material, and a subsequent road paver which has a machine frame carried by chain drives or wheels, on which a storage container is arranged for material to be installed and a screed for the installation of material. In addition, the invention relates to a method for operating a road milling machine and a road paver.

Different types of self-propelled construction machines are used in road construction. These machines include the well-known road milling machines with which existing road layers of the road surface can be removed. The known road milling machines have a rotating milling drum that is equipped with suitable milling or cutting tools for working the soil. The milling drum is arranged on the machine frame, the height of which is adjustable relative to the soil to be worked. The height of the machine frame is adjusted by means of a lifting device which has lifting columns assigned to the individual crawler tracks or wheels. To remove the milled material, the road milling machine has a conveyor with a conveyor belt. In addition, the known road milling machines have a control and computing unit with which the lifting device is controlled. The machine frame is lowered to mill off a defective road surface so that the milling drum penetrates the road surface. The lifting columns allow both the height adjustment of the machine frame or the milling drum as well as the setting of a predetermined inclination of the milling drum transversely to the feed direction of the road milling machine.

For the precise setting of the milling depth and milling inclination, the known road milling machines have milling depth regulating devices or leveling systems which have one or more measuring devices for measuring the distance between a reference point on the milling machine and the road surface to be machined. The known measuring devices have tactile sensors or non-contact sensors, for example ultrasonic sensors, for distance measurement. To measure elongated unevenness, measuring systems called multiplex leveling systems are used, which have several distance sensors arranged at a distance from one another in the longitudinal direction of the substrate to be processed, in order to be able to calculate an average value from the measured values of the individual sensors. The lifting columns are then controlled as a function of the mean value, so that minor unevenness can be largely compensated for. In the known multiplex systems, the distance sensors are attached to an elongated arm which is attached to one side of the machine frame.

Asphalt pavers are used to install the road material, which have a storage container to hold the mix and a screed. The mix is conveyed from the storage container to the screed with a conveyor, the mix being piled up in front of the screed in the production direction. Screeds are known to float on the material to be installed. This can largely compensate for minor unevenness in the surface. The screeds generally have a device for heating and compacting the material to be installed. Like the road milling machines, the road pavers can have a leveling device which can have one or more distance sensors.

In special paving situations it may be necessary to change the floating behavior of the screed. Known asphalt pavers therefore provide a floating mounting of the screed, which allows the screed to be raised and lowered, and the cross slope of the screed can also be changed. The leveling of the screed is changed or adjusted using a leveling device in relation to a reference line or reference surface.

In general, the material milled off by the road milling machine is taken from the construction site by truck to be processed in a processing plant to be able to. Prepared mix is then driven to the construction site by truck in order to be reinstalled with the paver. A road milling machine can also be operated together with a road paver as a machine train. The road milling machine in front is used as a recycler, which mills off the damaged road surface and processes the milled surface, for example, with additives such as bitumen emulsion, while the subsequent road paver re-installs the prepared surface. The conveyor device of the road milling machine conveys the milled material into the pavement container of the road paver.

If a paver is operated together with a road milling machine as a machine train, only a certain amount of material is available. During the advance of the two road construction machines, the paver can only install as much material as the road milling machine has previously milled. It should be taken into account that the volume of the material milled with the road milling machine per unit of time or route section can change continuously depending on the nature of the road surface. The volume of the material to be installed with the paver per unit of time or section is also not constant. For example, the compensation of a depression requires a larger volume of material for the corresponding route section. As a result, the position of the screed must be changed in order to achieve a uniform road surface. The proper operation of the paver also requires a sufficient amount of material in the reservoir.

From the DE 10 2006 020 293 A1 A leveling device for a road milling machine is known which provides a sensor on the left and right side of the road milling machine for detecting the actual value of the milling depth and a sensor for detecting the current inclination of the milling drum with respect to a reference surface. Depending on the deviation of the target values from the measured actual values, the milling depth can be specified on the left and right side of the machine. However, the milling depth can only be on one of the two sides be specified. In this case, in addition to the milling depth, a certain cross slope can be specified on only one side.

The EP 0 542 378 B1 describes a control device for a road milling machine, which has three ultrasonic sensors, which are arranged one behind the other in the feed direction of the milling machine. A side strip of the street is to be scanned with the ultrasonic sensors as a reference surface. Two distance sensors are located on the machine frame at the height of the drives and a sensor is arranged between the drives. The distance values are evaluated statistically, for example an average is formed in order to generate a control signal for the lifting device for height adjustment of the drives.

The EP 0 542 297 B1 proposes an ultrasound control device for a road paver, which has three ultrasound sensors arranged one behind the other in the feed direction of the paver, which are attached to a holder. The measured distance values are evaluated in order to generate a control signal for a leveling device for changing the position of the screed. Distance values outside the specified limits should be discarded. Unevenness in the scanned reference plane should be largely compensated for by averaging. It is disadvantageous that the detection of the distance values can only take place over a range that is determined by the sensors attached to the holder. Therefore, elongated bumps that are longer than the machine frame cannot be detected.

The US 2009/0317186 A1 describes a train from a preceding road milling machine, a road paver and a compressor, the road milling machine and the road paver have a device for generating height profile data. The document deals primarily with the problem of controlling the compressor depending on the local conditions. Therefore, the height profile data from the road milling machine and the paver are transmitted to the compressor for further processing. The US 2009/0317186 A1 suggests using the height profile data of the road milling machine for other aspects as well.

The invention has for its object to achieve an improved detection of the substrate in order to be able to detect elongated bumps. It is also an object of the invention to scan a reference surface or line for the operation of the road paver with a relatively small additional technical outlay.

According to the invention, these objects are achieved with the features of the independent claims. The dependent claims relate to advantageous embodiments of the invention.

The invention makes use of the fact that the road paver, which has a machine frame carried by chain drives or wheels, on which a receiving container for material to be installed and a screed for the installation of material is arranged, is preferably operated in combination with a road milling machine which is one of chain drives or wheels supported machine frame and a milling drum arranged on the machine frame for milling material. In principle, in deviation from the invention, it is also possible not to operate the road milling machine and road paver as a machine train, but to use the road milling machine in a first step and the road paver in a second step, the first and second step not having to follow one another directly. For example, there may be one or more hours or days between the two work steps.

The machine train from the preceding road milling machine and the subsequent road paver is characterized in that the road milling machine has a profile data determination device for the leveling device of the road paver, the profile data determination device being designed such that during the advance of the road milling machine a consequence of the height of the Road surface length profile data describing in the longitudinal direction can be determined. The reference line or reference surface, for example a strip of the road surface to be processed, is therefore not scanned with distance sensors which can be located on the road paver only within an area delimited by the geometric dimensions of the machine frame, but rather by means of the road milling machine in front. As a result, the road milling machine serves as a "scanner".

In this context, height profile data is understood to mean all data with which the profile of any strip or line extending in the longitudinal direction of the road surface to be processed can be described, for example the distance values between an assumed reference point or a reference line, for example the average profile in the center of the road, and another reference point or line on the road surface. Under Corresponding electrical signals are also understood as profile data. The elevation profile data can include absolute or relative distance values.

A data transmission device is provided on the road milling machine for transmitting the height profile data. In this context, a data transmission device is understood to mean all means with which data or signals can be transmitted. The data can be transmitted, for example, with electromagnetic or optical signals.

In the simplest case, the data transmission device can be a display unit on which the height profile data or data derived therefrom are displayed, so that the machine operator of the road paver or another person can recognize the height profile data. On the display unit, data derived from the height profile data can be visualized, for example, as symbols or the like, which can serve as work instructions for controlling the paver. However, the road paver preferably has a data receiving device so that the height profile data can be received by the road paver.

The data transmission device and data receiving device can be a transmitting and receiving device, which can comprise a radio transmitter and receiver, and can be part of a WLAN (Wireless Local Area Network), for example. The data transmission device can also include a device for reading data from a data carrier, for example a drive or a USB stick, and the data receiving device can include a device for reading data from a data carrier. Intermediate storage of the data on a data carrier is required if the road milling machine and the road paver are not operated as a machine train, but rather there is a certain period of time between the work step of recording and reading in the data.

To change the position of the screed, the paver has a leveling device that has at least one actuator and a control unit, which is designed such that the control unit is dependent on a height profile data set, which is obtained from the height profile data determined by the road milling machine, generates a control signal for actuating the at least one actuator.

As a result, the height profile data can be recorded in advance over a wide area of the road surface with the road milling machine before the material is installed in this area with the road paver. The height profile data can be temporarily stored in a memory for the period of time that the paver requires to cover the corresponding section of the route. This memory can be provided on the road milling machine or the road paver.

Obtaining the height profile data set from the height profile data requires an evaluation of the data or signals. Since the invention lies primarily in the provision of the data, it is not critical for the invention how the data is processed or evaluated and how the position of the screed is controlled with this data. For example, the recorded height profile data or data derived therefrom can only be shown on a display, on the basis of which the machine operator of the paver finishes manually controlling the position of the screed.

The height profile data record can be obtained from the height profile data using an evaluation device which can be provided in the road milling machine or the road paver. The evaluation device is preferably part of a control and computing unit of the road milling machine.

A preferred embodiment provides that the evaluation device is designed in such a way that the height profile data are statistically evaluated in order to obtain the height profile data set. The evaluation device is preferably designed in such a way that the statistical evaluation of the height profile data comprises averaging and / or the rejection of height profile data lying outside of predetermined limit ranges.

A further preferred embodiment provides that the road milling machine has a device for determining spatial data, wherein profile data determining device is designed such that spatial profile data is obtained from the altitude profile data. In the simplest case, the device for determining spatial data can be, for example, an odometer. The position in space can also be determined with a global positioning system (Global Navigation Satellite System (GNSS), e.g. GPS). With the additional room-related data, the height profile can be described for any point in the room.

The drives or wheels of the road milling machine are attached to the machine frame via lifting columns in such a way that the height of the machine frame relative to the surface of the ground can be changed in order to adjust the milling depth of the milling drum.

The acquisition of height profile data suitable for controlling the screed is particularly easy and reliable with the road milling machine in front if it can be assumed that changes in the height profile are only seen on one side, i.e. on the left or right side of the machine in the direction of travel are expected. When repairing roads, this situation often arises from the fact that the road surface of a road in need of renovation has no or only slight bumps in the middle of the road, while the road surface in the edge area of the road often has strong bumps, for example due to settling in the banquet area. When machining with a road milling machine with a milling width of, for example, about 2 meters, one track is then removed per work step, with one machine side moving on the hardly worn center of the road and the other machine side moving over the edge of the road with relatively large unevenness .

In this case, height profile data suitable for controlling the screed can be recorded particularly easily and reliably with the road milling machine in front, since the road milling machine according to the invention has a cross-slope sensor which, depending on the cross-slope of the machine frame and / or the milling drum, produces a sequence of cross-slope Data generated, the profile data determining device is designed in such a way that the height profile data are obtained from the bank data determined with the bank sensor. It is assumed that the cross slope of the road milling machine describes the height profile of the road surface on one side of the road in the longitudinal direction. For this purpose, the road milling machine has a milling depth control device for controlling the lifting columns, which has a first measuring device for measuring the distance from a reference point on the road milling machine to the surface of the unworked soil on the left side of the milling drum in the working direction and a second measuring device for measuring the distance a reference point on the road milling machine to the surface of the unworked soil on the right side of the milling drum in the working direction, the milling depth control device being designed in such a way that the lifting columns are controlled in such a way that when the road milling machine is advanced, the milling depth on the left in the working direction and right side of the milling drum is kept substantially constant regardless of the nature of the soil surface. This milling depth control means that, regardless of the nature of the substrate, a predetermined layer thickness is removed across the entire width of the milling drum or roadway. As a result, the cross slope of the machine frame and the milling drum on the machine frame can change when the road milling machine is advanced in accordance with the profile of the road surface. Assuming that the profile on one of the two sides of the carriageway does not change in the longitudinal direction, the inclination of the road milling machine provides information about the nature of the height profile in the longitudinal direction of the carriageway on the other side, on which the height profile changes, for example due to settling in the banquet area changes. A large depression in the road surface can, for example, lead to a greater inclination of the machine frame than a smaller depression. According to the invention, the road milling machine has the cross slope sensor for this purpose, which generates a sequence of cross slope data as a function of the cross slope of the machine frame with such a milling depth control, so that the profile data determination device can obtain the height profile data from the cross slope data, since the cross slope data at describe the height profile of such a milling depth control.

Tactile sensors, for example cable pull sensors or contactless sensors, for example ultrasonic sensors, can be used to record the milling depth. For example, a cable pull sensor can detect the position of the left and / or right edge protector, which is floating on the floor surface, relative to the machine frame. If the milling depth is increased, the edge protector moves up relative to the machine frame by an amount corresponding to the change in the milling depth. If, on the other hand, the milling depth is reduced, the edge protector moves down relative to the machine frame by an amount that corresponds to the change in the milling depth.

If the milling drum moves over a depression in the road surface, the edge protection is shifted downwards, from which a reduction in the milling depth relative to the road surface can be concluded. If, on the other hand, the road surface has ridges, the edge protection is shifted upwards relative to the machine frame, which results in an increase in the milling depth. A milling depth control is preferably designed such that a certain milling depth is specified. If the milling depth sensors detect a deviation of the sensor (ACTUAL) values from the specified (TARGET) values, the milling depth is corrected. Since milling depth sensors can be provided on both sides of the milling drum, a (possibly also the same) milling depth can be specified for each side of the milling drum. If a deviation of the sensor (ACTUAL) value from the specified (TARGET) value is determined on only one side, for example on the left side of the milling drum, the height of the machine frame is adjusted only on the left side, for example by or only extend the lifting columns on the left side of the machine frame. If there is a depression in the road surface on the left side of the machine, this is recognized by the left milling depth sensor as a reduction in the milling depth. In response to this, the lifting columns on the left side of the machine frame are retracted to increase the milling depth again.

An alternative embodiment, which is not the subject of the invention, provides that the road milling machine has a milling depth control device for controlling the lifting columns, which has a measuring device for

Measuring the distance of a reference point on the road milling machine to the surface of the unprocessed soil on one of the two sides of the milling drum, the milling depth control device being designed in such a way that the lifting columns are controlled in such a way that when the road milling machine is advanced, the milling depth on the one the two sides of the milling drum is kept essentially constant regardless of the nature of the soil surface. A cross slope control device is provided, which is designed such that the lifting columns are controlled in such a way that the cross slope of the machine frame when the road milling machine is advanced is kept essentially constant regardless of the nature of the ground surface, so that a specific profile for the road surface is included a certain bank slope can be specified. If a measuring device is provided for measuring the distance of a reference point on the road milling machine to the surface of the unprocessed soil on the other of the two sides of the milling drum, the height profile data can be obtained from the sequence of the measured distance values. In this embodiment, the profile data determination device is designed such that the height profile data are obtained from the distance data.

The milling depth controls described above, which is a prerequisite for determining the height profile data from the bank data or distance data, are known from the prior art. These milling depth regulations are, for example, in the DE 10 2006 020 293 A described in detail.

An exemplary embodiment of the invention is explained in detail below with reference to the drawings.

Fig. 1

eine Seitenansicht einer Straßenfräsmaschine in vereinfachter Darstellung,

Fig. 2

eine vereinfachte perspektivische Darstellung eines Straßenfertigers und

Fig. 3

eine stark vereinfachte schematische Darstellung des Maschinenzuges aus Straßenfräsmaschine und Straßenfertiger mit den für die Erfassung und Übertragung der Höhenprofil-Daten wesentlichen Komponenten.

Show it:

Fig. 1

a side view of a road milling machine in a simplified representation,

Fig. 2

a simplified perspective view of a paver and

Fig. 3

a highly simplified schematic representation of the machine train from road milling machine and road paver with the essential components for the acquisition and transmission of the height profile data.

Fig. 1 shows a side view of a self-propelled road milling machine for milling road surfaces in a simplified representation. The road milling machine 1 has a machine frame 3 carried by a chassis 2. The chassis 2 of the milling machine comprises front and rear chain drives 4 and 5, which are arranged on the right and left side of the machine frame 3 in the working direction A. Instead of chain drives, wheels can also be provided.

In order to adjust the height and / or inclination of the machine frame 3 relative to the surface of the floor 6, the road milling machine has a lifting device 7 which comprises lifting columns 8 and 9 assigned to the individual crawler tracks 4, 5 and by which the machine frame 3 is carried.

The road milling machine 1 also has a milling drum 10 equipped with milling tools, which is arranged on the machine frame 3 between the front and rear chain drives 4, 5 in a milling drum housing 11 which is closed on the longitudinal sides by a left and right edge protector 12. A conveyor device 13 with a conveyor belt 14 is provided for removing the milled off road surface. The conveyor device 13 is arranged at the rear end of the road milling machine, as seen in working direction A, so that the milled material can be loaded from the road milling machine driving ahead onto a subsequent road paver. Above the milling drum housing 11, the operator's platform 15 is located on the machine frame 3.

By retracting and extending the lifting columns 8, 9 of the lifting device 7, the height and inclination of the machine frame 3 and the milling drum 10 arranged on the machine frame with respect to the floor surface 6 can be adjusted. In principle, however, it is also possible to change the height and inclination of the milling drum compared to the fixed machine frame.

Fig. 2 shows a simplified perspective view of a self-propelled paver 16. The paver has a machine frame 18 carried by crawler tracks 17 (crawler paver). Instead of chain drives, wheels can also be provided (wheel pavers). In a front area of the machine frame 18 in the working direction A, a storage container 19 is arranged for receiving the material to be installed. At the rear of the paver 16 there is a screed 20 for paving the material. The operator station 21 is arranged between the storage container 19 and the screed 20.

The screed 20 is designed as a screed floating on the material to be installed. For this purpose, the screed 20 is movably connected to the machine frame 18 via bars 22 which are provided on both sides of the machine frame 18.

The paver 16 has a leveling device 23 ( Fig. 3 ) to compensate for short and elongated bumps in the subsoil, so that a roadway can be produced in the desired flatness and paving thickness. The leveling device 23 has actuators 24 for changing the position of the screed 20 and a control unit 23A ( Fig. 3 ), which generates control signals for actuating the actuators 24.

The desired paving thickness is achieved in particular by adjusting the angle of attack of the screed 20, which is determined by the height of a screed pull point. To adjust the screed point, the actuators 24 of the leveling device 23 can comprise leveling cylinders 26 provided on the sides of the machine frame 18. With the leveling cylinders 26, not only the angle of attack of the screed 20, but also the inclination of the screed can be adjusted transversely to the production direction A.

The control unit 23A of the leveling device 23 is configured such that the position of the screed 20 is set on the basis of a height profile data record which comprises a sequence of height profile data describing the height of the road surface 6 in the longitudinal direction.

The road milling machine 1 from Fig. 1 and the paver 16 from Fig. 2 are operated according to the invention as a machine train, with the road milling machine 1 driving ahead providing the height profile data from which the height profile data record for the leveling device 23 of the subsequent road finisher 16 is obtained.

The following will refer to Fig. 3 described in detail how the height profile data are determined by the road milling machine 1 and how the height profile data set is obtained from the height profile data. Fig. 3 shows the machine train from road milling machine 1 and road paver 16 with the essential components for the acquisition and transmission of the height profile data in a highly simplified schematic representation.

The height profile data are transmitted from the road milling machine 1 to the road paver 16. The road milling machine 1 has a data transmission device 27 for transmitting the height profile data and the road paver 16 has a data reception device 28 for receiving the height profile data. The data transmission device and the data reception device can be a transmitting and receiving device 27, 28. In the present exemplary embodiment, the transmitting device 27 is a radio transmitter and the receiving device 28 is a radio receiver, so that the signals can be transmitted wirelessly. Radio transmitters and radio receivers can be part of a WLAN.

In the present exemplary embodiment, the road surface of a damaged roadway is milled off with the road milling machine 1 and the milled and reprocessed material is reinstalled as a new surface using the road paver 16.

The road milling machine 1 moves at a predetermined feed speed, for example on the right half of the road, the milling drum 10 extending transversely to the working direction A over the width of the right half of the road.

In Fig. 3 the original profile is shown in the middle of the street (middle gradient) and in the area of the right side of the street (outer gradient). The center gradient 29 essentially shows no depressions or elevations. However, 30 depressions 31 or elevations can be clearly recognized on the external gradient. The height of the carriageway along a line in the longitudinal direction of the carriageway, ie the central or external gradient, is plotted on the Y axis, and the distance is plotted on the X axis. Δz _n denotes the vertical distance between the center gradient 29 and the outer gradient 30 at a point a _n on the route, for example Δz ₁ denotes the vertical distance between the center gradient 29 and the outer gradient 30 at the waypoint a ₁ . The road is inclined to the edge by the angle α. The angle α is dependent on the horizontal distance and the vertical distance Δz _n between the center gradient 29 and the outside gradient 30. Since the horizontal distance between the center gradient 29 and the outside gradient 30 is known and remains constant in the course of tillage, the angle α is at the waypoint a _n suitable to determine the vertical distance Δz _n .

The milling machine has a milling depth control device 33 for controlling the lifting columns 8, 9, which has a first measuring device 33A for measuring the distance from a reference point on the road milling machine 1 to the surface of the unprocessed soil on the left side of the milling drum 10 and in the working direction A. / or a second measuring device 33B for measuring the distance of a reference point on the road milling machine to the surface of the unworked soil on the right side of the milling drum 10 in the working direction A.

To record the height profile, the road milling machine 1 according to the invention is preferably operated with the milling depth control device 33 in such a way that the road surface machined with the milling drum 10 represents a copy of the unworked surface, ie the same layer thickness is always largely removed in the longitudinal direction over the entire width of the milling drum . For this purpose, the current measuring depth is detected by the two measuring devices 33A, 33B on the right or left side of the milling drum 10. If one of the milling depth measuring devices 33A, 33B detects a different milling depth, a corresponding correction is made. For example, there is a depression in the edge of the street If present, this is compensated for by increasing the milling depth on this side of the machine frame 3 by retracting the lifting columns 8, 9, for example piston-cylinder arrangements, on this side. However, if there is an increase in the edge area, the milling depth is reduced by extending the lifting columns on this side of the machine frame. If one assumes that the center of the carriageway is largely free of bumps, it follows that hardly any control intervention by the milling depth control is necessary on the side of the machine frame oriented towards the carriageway center. Experience has shown, however, that the edge of a road in need of renovation (due to settling in the banquet area, uneven loads, etc.) often has bumps, so that control interventions are often necessary on the machine side facing the edge area.

Due to the control interventions of the milling depth control device 33, the cross slope of the machine frame 3 changes when the milling machine is advanced. The changing cross slope can thus be understood as a measure of the depth of the depression in relation to an average height of the road surface, in particular the central gradient. H. the cross slope of the machine frame describes the height profile of the road surface at the edge of the road.

To measure the distance Δx between a reference point on the road milling machine and the non-machining road surface, the first or second measuring device 33A, 33B can have a distance sensor, which can be a tactile or non-contact distance sensor. For example, the distance sensor can be an ultrasonic sensor. The distance sensor can also be a sensor that detects the position of the left or right edge protector 12 of the milling machine, for example a cable pull sensor. The two measuring devices 33A, 33B generate a measuring signal which correlates with the distance and which the milling depth control device 33 of the road milling machine 1 receives. The milling depth control device 33 is configured such that the lifting columns 8, 9 are retracted or extended in dependence on the measurement signals in such a way that when the road milling machine is advanced, the milling depth on the left and right sides of the milling drum 10 in the working direction is independent of the Condition of the soil surface is kept essentially constant. Such a milling depth control device is from the DE 10 2006 020 293 A1 known.

The road milling machine 1 also has a profile data determination device 36, which has a bank sensor 37. The cross slope α of the machine frame 3 or the milling drum 10 which changes as a result of bumps is detected by the cross slope sensor 37 during the advancement of the road milling machine. The cross slope can be measured continuously during the feed or at predetermined time intervals in order to generate the height profile data. The height profile data can be, for example, the data of the bank sensor 37 read out at certain time intervals by the profile data determining device. From the data of the Quemeigungssensors 37, the profile data determining means 36 determines during the feed of the milling machine, a sequence of the height of the profile at the coordinate points a _1, a _2, a ₃ ... a _n descriptive height profile data (Az _1, Az ₂ , Δz ₃ , ..., Δz _n ), If a road milling machine already has this milling depth control device, additional components for determining the height profile data are not required.

The profile data determination device 36 can have a global position determination system (GPS) 38, which at the times at which the data of the bank sensor 37 are read out, ie at the waypoints a ₁ , a ₂ , a ₃ ..., a _n positions -Data (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ) ... (x _n , y _n ) are available to extract from the height profile data (Δz ₁ , Δz ₂ , Δz ₃ , ..., Δz _n ) to determine spatial height profile data. The profile data determining device 36 which, during the advancement of the milling machine, a sequence of height profile data (Δz ₁ , Δz ₂ , Δz ₃ ,...) Describing the height of the profile at the waypoints a ₁ , a ₂ , a ₃ ... a _n . .., Δz _n ) determines the height profile data at the individual waypoints, the data determined with the GPS system (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ) .. . (x _n , y _n ) to. To determine the position data (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ) ... (x _n , y _n ), a distance counter can also be provided. The position data can also be calculated from the feed rate and the time required by the road milling machine 1 to reach a specific waypoint a ₁ , a ₂ , a ₃ ... a _n .

From the spatial altitude profile data Δz _n (x _n , y _n ) a spatial altitude profile data set [file: (Δz ₁ (x ₁ , y ₁ ), Δz ₂ (x ₂ , y ₂ ), Δz ₃ (x ₃ , y ₃ ) ... Δz _n (x _n , y _n )], which describes the relative height profile in the longitudinal direction of a certain section of road, in particular along the external gradient.

However, it is also possible to determine an absolute height profile.
In this case, the absolute height of the center gradient 29 is determined. If the absolute height of the center gradient 29 is known, absolute height profile data (z ₁ , z ₂ , z ₃ , ..) can be obtained from the relative height profile data (Δz ₁ , Δz ₂ , Δz ₃ , ..., Δz _n ). ., z _n ) and a space-related absolute elevation profile data record are calculated, which describes the absolute elevation profile in the longitudinal direction of a certain road section, in particular along the external gradient.

To obtain the height profile data set, an evaluation device 39 is provided, which can be provided in the road milling machine 1 or the road paver 16. If the evaluation device 39 is provided in the road milling machine 1, the entire data set or a part of the data set is transmitted to the data receiving device 28 with the data transmission device 27. The evaluation device 39 is preferably provided in the road milling machine 1. The evaluation device 39 can then be part of the milling depth control device 33 of the road milling machine 1.

The evaluation device 39 can be configured such that the height profile data are evaluated according to known statistical evaluation methods. In the present exemplary embodiment, the mean value can be formed from the measured cross slopes. Furthermore, it can be provided in the exemplary embodiment that data lying outside of predetermined limit ranges are discarded before the averaging. These measured values are based on the assumption that there are incorrect measurements, or that the measuring device was not detecting the road surface itself, but rather objects lying on the road, for example larger stones.

In the paver 16, the height profile data set can be used to control the actuators 24 of the leveling device 23 of the paver 16. The control unit 23A of the leveling device 23 can be configured, for example, in such a way that the leveling cylinders 26 are retracted or extended based on the height profile data record. For example, depending on the height profile data, the angle of attack and / or the transverse inclination of the screed 20 can be set. In the present exemplary embodiment, the transverse slope of the screed 20 is changed as a function of the height profile in such a way that depressions on the right-hand side of the carriageway are compensated for. In the case of a depression, for example, the incline of the screed 20 is reduced, so that a larger amount of material is installed on the right side. With a suitable evaluation algorithm, unevenness in the subsurface can be compensated.

Alternatively, the necessary changes in the angle of attack and / or the transverse inclination of the screed 20 can already be determined by the evaluation device 39 on the basis of the height profile data set. If the evaluation device 39 is provided on the road milling machine 1, it is sufficient in this case if the data transmission device 27 does not transmit the entire height profile data record, but only control instructions for the actuators, in particular to a data reception device 28.

It is advantageous that the height profile data record determined with the road milling machine 1 driving in front can include data over a larger section of the road without a large number of sensors being required to determine this data. There is also no need for a boom on the paver 16 for fastening a plurality of sensors, the spatial dimensions of which would otherwise be essentially limited to the length of the paver. Even the gradients of winding roads can be easily recorded and made available to the paver.

The milling depth control device 33 of the road milling machine 1 and the leveling device 23 of the road paver 16 can, for example, be a general one Processor, a digital signal processor (DSP) for the continuous processing of digital signals, a microprocessor, an application-specific integrated circuit (ASIC), an integrated circuit consisting of logic elements (FPGA) or other integrated circuits (IC) or hardware components to control of the actuators. A data processing program (software) can run on the hardware components. A combination of the different components is also possible.

An alternative embodiment, which is not the subject of the invention, requires a milling depth control device, which is known in the prior art, for controlling the lifting columns 8, 9 and which is a measuring device for measuring the distance of a reference point on the road milling machine from the surface of the unprocessed soil on only one of the two sides of the milling drum 10. In the present exemplary embodiment, a measuring device 33A is provided only on the left side of the machine frame 3. The milling depth control device 33 is designed such that the lifting columns 8, 9 are retracted or extended in such a way that when the road milling machine is advanced, the milling depth on one of the two sides of the milling drum is kept essentially constant regardless of the nature of the ground surface . In the present embodiment, the milling depth on the left side is kept constant. In addition, a cross slope control device 40 is provided, which is designed in such a way that the lifting columns 8, 9 are controlled in such a way that the cross slope of the machine frame 3 is kept essentially constant when the road milling machine is advanced, regardless of the nature of the ground surface, so that results in a predetermined cross slope for the milled surface. However, this means that the same layer thickness is not always removed on the right-hand side in the longitudinal direction, for example only a smaller layer thickness in the region of a depression and a greater layer thickness than the average layer thickness in the region of an increase. The bank control device can be part of the milling depth control device, which in turn can be part of a central control and computing unit.

With a second measuring device 33B for measuring the distance of a reference point on the road milling machine to the surface of the unworked ground on the another of the two sides of the milling drum 10, in the present exemplary embodiment on the right side, a sequence of distance data is generated. In this exemplary embodiment, the profile data determination device 36 is designed such that the height profile data are obtained from the distance data of the second measuring device 33B. Such a milling depth control device, which has two measuring devices on the left and right side and a bank inclination control for setting a specific bank inclination, is from the DE 10 2006 020 293 A1 known.

Claims (13)

1. Machine train composed of a road milling machine (1) that travels in front and comprises a machine frame (3) supported by crawler tracks (3, 4) or wheels and a milling drum (10) arranged on the machine frame that is for milling away material, and a road finisher (16) that travels behind and comprises a machine frame (18) which is supported by crawler tracks (17) or wheels and on which a reservoir (19) for material to be laid and a screed (20) for laying material are arranged, wherein the road finisher (16) comprises a levelling device (23) for adjusting the position of the screed (20), and the levelling device (23) is configured so that the position of the screed (20) in relation to a reference line or reference surface can be changed, wherein
   the road milling machine (1) comprises a profile data determining device (36) for the levelling device (23) of the road finisher (16), the profile data determining device (36) being configured so that a sequence of height profile data describing the height of the road surface (6) in the longitudinal direction is determined while the road milling machine advances, and comprises a data transmission device (27) for transmitting the height profile data to the road finisher, and
   the tracks (4, 5) or wheels of the road milling machine (1) are fastened via lifting columns (8, 9) to the machine frame (3) in such a manner that the height of the machine frame (3) relative to the surface of the ground can be changed in order to adjust the milling depth of the milling drum (10),
   characterized in that
   the milling machine comprises a milling depth control device (33) that is for controlling the lifting columns (8, 9) and comprises a first measurement device (33A) for measuring the distance of a reference point on the road milling machine (1) to the surface of the unprocessed ground on the left side of the milling drum (10) as seen in the working direction (A), and a second measurement device for measuring the distance of a reference point on the road milling machine to the surface of the unprocessed ground on the right side of the milling drum (10) as seen in the working direction A, wherein the milling depth control device (33) is configured so that the lifting columns (8, 9) are controlled such that when the road milling machine advances, the milling depth on the left and right side of the milling drum as seen in the working direction is kept substantially constant, regardless of the condition of the ground surface, and wherein
   the road milling machine (1) comprises a transverse incline sensor (37) that generates a sequence of transverse incline data in accordance with the transverse incline of the machine frame (3), wherein the profile data determining device (36) is configured so that the height profile data is obtained from the transverse incline data.
2. Machine train according to claim 1, characterised in that the road finisher comprises a data receiving device (28) for receiving the height profile data.
3. Machine train according to either claim 1 or claim 2, characterised in that the levelling device (23) of the road finisher (16) comprises at least one actuator (24) for changing the position of the screed (20), and a control unit (23A) that is configured so that the control unit (23A) generates a control signal for controlling the at least one actuator (24) in accordance with a height profile data set obtained from the height profile data.
4. Machine train according to claim 3, characterised in that the road milling machine (1) or the road finisher (16) comprises an assessment device (39) that is configured so that the height profile data is assessed statistically in order to obtain the height profile data set.
5. Machine train according to claim 4, characterised in that the assessment device (39) is configured so that the statistical assessment of the height profile data comprises taking an average value and/or discarding height profile data lying outside predetermined boundary ranges.
6. Machine train according to either claim 4 or claim 5, characterised in that the assessment device (39) is provided on the road milling machine (1).
7. Machine train according to any of claims 1 to 6, characterised in that the road milling machine (1) comprises a device (38) for determining spatial data, wherein the profile data determining device (36) is configured so that spatial height profile data is obtained from the height profile data.
8. Method for operating a road milling machine (1) that travels in front and comprises a machine frame (3) supported by crawler tracks (4, 5) or wheels and a milling drum (10) arranged on the machine frame that is for milling away material, and a road finisher (16) that comprises a machine frame (18) which is supported by crawler tracks (17) or wheels and on which a reservoir (19) for material to be laid and a screed (20) for laying material are arranged, wherein the position of the screed in relation to a reference line or reference surface can be changed, wherein in order to adjust the position of the screed (20) of the road finisher (16), a sequence of height profile data describing the height of the road surface in the longitudinal direction being determined while the road milling machine advances, and the height profile data being transmitted with a data transmission device (27) to the road finisher,
   characterised in that,
   that the distance of a reference point on the road milling machine (1) to the surface of the unprocessed ground on the left side of the milling drum (10) as seen in the working direction (A) and the distance of a reference point on the road milling machine to the surface of the unprocessed ground on the right side of the milling drum (10) as seen in the working direction (A) are measured, wherein the milling depth of the milling drum (10) is controlled such that when the road milling machine advances, the milling depth on the left and right side of the milling drum as seen in the working direction is kept substantially constant, regardless of the condition of the ground surface, and wherein the transverse incline of the machine frame (3) of the road milling machine (1) is measured, a sequence of transverse incline data is generated in accordance with the transverse incline, and the height profile data is obtained from the transverse incline data.
9. Method according to claim 8, characterised in that the height profile data is received by a data receiving device (28) of the road finisher (16).
10. Method according to either claim 8 or claim 9, characterised in that at least one actuator (24) is controlled in order to change the position of the screed (20) in accordance with a height profile data set obtained from the height profile data.
11. Method according to claim 10, characterised in that the height profile data is assessed statistically in order to obtain the height profile data set.
12. Method according to claim 11, characterised in that the statistical assessment of the height profile data comprises taking an average value and/or discarding height profile data lying outside predetermined boundary ranges.
13. Method according to any of claims 8 to 12, characterised in that spatial height profile data is obtained from the height profile data.

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