EP3741914B1 - 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 consisting of a road milling machine driving ahead, which has a machine frame carried by crawler tracks or wheels and a milling drum arranged on the machine frame for milling off material, and a following road finisher, which has a machine frame carried by crawler tracks or wheels, on which a storage container is arranged for material to be installed and a screed for installing material. In addition, the invention relates to a method for operating a road milling machine and a road finisher.

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 ground. The milling drum is arranged on the machine frame, the height of which can be adjusted in relation to the soil to be processed. 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. The road milling machine has a conveying device with a conveyor belt for removing the milled material. In addition, the known road milling machines have a control and computing unit with which the lifting device is controlled. To mill off a damaged road surface, the machine frame is lowered 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 and the setting of a predetermined inclination of the milling drum transverse to the direction of advance of the road milling machine.

For precise setting of the milling depth and milling inclination, the known road milling machines have milling depth control devices or leveling systems that have one or more measuring devices for measuring the distance between a reference point on the milling machine and the road surface to be processed. The known measuring devices have tactile sensors or non-contact sensors, for example ultrasonic sensors, for distance measurement. Measuring systems known as multiplex leveling systems are used to measure elongated unevenness. The lifting columns are then controlled depending on the mean value, so that minor unevenness can be largely compensated. In the known multiplex systems, the distance sensors are fastened to an elongate arm which is attached to one side of the machine frame.

Road finishers are used to pave the road material, which have a storage container for receiving the mixed material and a screed. The mixed material is conveyed from the storage container to the screed by a conveying device, with the mixed material being piled up in front of the screed in the production direction. There are known screeds that float on the material to be paved. This means that minor unevenness in the subsurface can be largely leveled out. The screeds generally have a device for heating and compacting the material to be paved. Like the road milling machines, the road finishers can have a leveling device that can have one or more distance sensors.

In special paving situations, it may be necessary to change the floating behavior of the screed. Known road finishers therefore provide for a floating mounting of the screed, which allows the screed to be raised and lowered, and the transverse inclination of the screed can also be changed. The position of the screed is changed or adjusted with a leveling device in relation to a reference line or reference surface.

In general, the material milled by the road milling machine is transported from the construction site by truck to be processed in a processing plant to be able to. Prepared mix is then trucked to the site for repaving with the paver. However, a road milling machine can also be operated together with a road finisher 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 road paver following behind re-paves the processed surface. The conveyor system of the road milling machine conveys the milled material into the road finisher's reservoir.

If a road finisher is operated together with a road milling machine as a machine train, only a certain amount of material is available. While the two road construction machines are advancing, the road finisher can only pave as much material as the road milling machine has previously milled off. It must be taken into account that the volume of material milled off with the road milling machine per unit of time or route section can change constantly depending on the condition of the road surface. The volume of material to be paved with the road finisher per unit of time or distance section is also not constant. For example, leveling a depression requires a larger volume of material for the corresponding section of track. Consequently, the position of the screed has to be changed in order to achieve an even road surface. Proper operation of the paver also requires a sufficient amount of material in the hopper.

From the DE 10 2006 020 293 A1 a leveling device for a road milling machine is known, which provides a sensor for detecting the actual value of the milling depth and a sensor for detecting the current inclination of the milling drum in relation to a reference surface on the left and right side of the road milling machine. 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 also only be on one of the two sides be specified. In this case, in addition to the milling depth, a certain transverse slope can be specified on just one side.

the EP 0 542 378 B1 describes a control device for a road milling machine that has three ultrasonic sensors that are arranged one behind the other in the direction of advance of the milling machine. A hard shoulder of the road is to be scanned with the ultrasonic sensors as a reference area. Two distance sensors are on the machine frame at the level of the drives and one sensor is located between the drives. The distance values are evaluated statistically, for example an average value is formed in order to generate a control signal for the lifting device for adjusting the height of the carriages.

the EP 0 542 297 B1 proposes an ultrasonic control device for a road finisher, which has three ultrasonic sensors arranged one behind the other in the advance direction of the finisher and fastened 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 lying outside specified limits should be discarded. Unevenness of the scanned reference plane should be largely compensated for by averaging. The disadvantage is that the distance values can only be detected over a range that is determined by the sensors attached to the holder. Therefore, elongated bumps that extend longer than the machine frame cannot be detected.

the US2009/0317186 A1 describes a train consisting of a road milling machine driving ahead, a road finisher and a compactor. The road milling machine and the road finisher have a device for generating height profile data. The citation deals primarily with the problem of controlling the compactor as a function of local conditions. Therefore, the height profile data from the road milling machine and paver is transferred to the compactor for further processing. the U.S. 2009/0317186 A1 suggests using the elevation profile data from the road milling machine for other aspects as well.

The object of the invention is to achieve improved detection of the subsoil in order to also be able to detect elongated unevenness. Another object of the invention is to scan a reference surface or reference line for the operation of the road finisher with relatively little additional technical effort.

These tasks are solved according to the invention 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 supported by crawler tracks or wheels, on which a receptacle for material to be paved and a screed for paving material is arranged, is preferably operated in combination with a road milling machine that has one of crawler gears or wheels carried machine frame and arranged on the machine frame milling drum for milling off material. In principle, it is also possible not to operate the road milling machine and road finisher as a machine train, but to use the road milling machine in a first work step and the road finisher in a second work step, with the first and second work steps not having to follow one another directly. For example, one or more hours or days can lie between the two work steps.

The machine train consisting of the road milling machine driving ahead and the road finisher following behind is characterized in that the road milling machine has a profile data determination device for the leveling device of the road finisher, the profile data determination device being designed in such a way that during the advance of the road milling machine a sequence of the height of the Elevation profile data describing the road surface in the longitudinal direction are determined. The reference line or reference area, for example a strip of the road surface to be processed, is not scanned with distance sensors, which can only be located on the road finisher within an area limited by the geometric dimensions of the machine frame, but by means of the road milling machine driving ahead. Thus, the road milling machine serves as a "scanner".

In this context, height profile data means 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 mean profile in the middle of the road, and another reference point or line on the road surface. Under Profile data are also understood as corresponding electrical signals. The elevation profile data can include absolute or relative distance values.

A data transmission device is provided on the road milling machine to transmit the elevation 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, using 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 finisher or another person can see the height profile data. Data derived from the elevation profile data can be visualized on the display unit, for example as symbols or the like, which can serve as work instructions for controlling the finisher. However, the road finisher preferably has a data receiving device, so that the height profile data can be received by the road finisher.

The data transmission device and data reception device can be a transmission and reception device, which can include 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 onto 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. Temporary storage of the data on a data carrier is necessary if the road milling machine and the road finisher are not operated as a machine train, but 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 road finisher has a leveling device that has at least one actuator and a control unit that is designed in such a way that the control unit, depending 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 controlling the at least one actuator.

Consequently, the elevation profile data can be recorded over a wide area of the road surface with the road milling machine in advance, before the road finisher is used to lay the material in this area. The height profile data can be temporarily stored in a memory for the period of time that the road finisher needs to cover the corresponding route section. This memory can be provided on the road milling machine or the road finisher.

Obtaining the height profile data record from the height profile data requires an evaluation of the data or signals. Since the invention lies above all in the provision of the data, it is not decisive 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 height profile data recorded or data derived therefrom can only be shown on a display, which the machine operator of the road finisher uses to manually control the position of the screed.

The height profile data set can be obtained from the height profile data using an evaluation device which can be provided in the road milling machine or the road finisher. 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 is 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 includes an averaging and/or the rejection of height profile data lying outside predetermined limit ranges.

A further preferred embodiment provides that the road milling machine has a device for determining spatial data, the profile data determination device being designed in such a way that spatial elevation profile data are obtained from the elevation profile data. In the simplest case, the device for determining space-related data can be an odometer, for example. However, the position in space can also be determined using a global positioning system (Global Navigation Satellite System (GNSS), eg GPS). With the additional spatial data, the elevation profile can be described for any point in space.

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 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 driving ahead, if it can be assumed that changes in the height profile will only occur on one side, i.e. on the left or right side of the machine when viewed in the direction of travel are expected. This situation often arises when repairing roads because the road surface of a road in need of repair 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 severe bumps, for example due to subsidence in the shoulder area. When working with a road milling machine with a milling width of about 2 meters, for example, one track is then removed per operation, with one side of the machine moving on the hardly worn middle of the road and the other side of the machine moving over the edge area of the road with relatively large bumps .

In this case, height profile data suitable for controlling the screed can be recorded particularly easily and reliably with the road milling machine driving ahead if the road milling machine has a transverse slope sensor that Depending on the transverse gradient of the machine frame and/or the milling drum, a sequence of transverse gradient data is generated, with the profile data determination device being designed in such a way that the height profile data are obtained from the transverse gradient data determined using the transverse gradient sensor. It is assumed that the transverse gradient of the road milling machine describes the height profile of the road surface on one side of the road in the longitudinal direction. This applies when 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 between a reference point on the road milling machine and the surface of the unprocessed soil on the left side of the milling drum in the working direction, and a second measuring device for measuring the distance between a reference point on the road milling machine and the surface of the uncultivated soil on the right-hand 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 advances, the milling depth the left and right side of the milling drum in the working direction is kept essentially constant, regardless of the condition of the soil surface. This regulation of the milling depth results in a predetermined layer thickness being removed across the entire width of the milling drum or roadway, regardless of the nature of the subsoil. As a result, the transverse inclination of the machine frame and the milling drum on the machine frame can change in accordance with the profile of the road surface when the road milling machine is advanced. Assuming that the profile on one of the two sides of the roadway 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 roadway on the other side, where the height profile changes, for example due to settlement in the shoulder area changes. For example, a large depression in the road surface may cause the machine frame to tilt more than a smaller depression.

If the road milling machine has a transverse slope sensor that generates a sequence of transverse slope data as a function of the transverse slope of the machine frame in such a milling depth control, the profile data determination device can Gain elevation profile data from the transverse slope data, since the transverse slope data describe the elevation profile in such a milling depth control.

However, the embodiment described above with such a milling depth control is not the subject of the invention.

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

When the milling drum moves over a depression in the road surface, the edge protection is shifted downwards, which indicates a reduction in the milling depth relative to the road surface. If, on the other hand, the road surface is raised, the edge protection is shifted upwards relative to the machine frame, resulting in an increase in the milling depth. A milling depth control is preferably designed in such a way that a specific 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 milling depth (possibly also the same) milling depth can be specified for each side of the milling drum. If the sensor (ACTUAL) value deviates from the specified (SET) value on only one side, for example on the left side of the milling drum, the height of the machine frame is only adjusted on the left side, for example by or extend only the lifting columns on the left side of the machine frame. If there is an indentation in the road surface on the left side of the machine, it will be detected by the left milling depth sensor as a reduction in milling depth recognized. In response, the lifting columns on the left side of the machine frame are retracted to increase the milling depth again.

The road milling machine according to the invention provides a milling depth control device for controlling the lifting columns, which has a measuring device for

Measuring the distance from a reference point on the road milling machine to the surface of the unworked ground 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 advances, the milling depth is on one of the two sides of the milling drum is kept essentially constant regardless of the condition of the ground surface. A transverse inclination control device is provided, which is designed in such a way that the lifting columns are controlled in such a way that the transverse inclination of the machine frame is kept essentially constant when the road milling machine is advanced, regardless of the condition of the ground surface, so that the road surface has a specific profile a certain transverse inclination can be specified. According to the invention, a measuring device is provided for measuring the distance between a reference point on the road milling machine and the surface of the unprocessed soil on the other of the two sides of the milling drum, so that the height profile data can be obtained from the sequence of measured distance values. In this embodiment according to the invention, the profile data determination device is designed in such a way that the height profile data is obtained from the distance data.

The milling depth regulations described above, which are a prerequisite for determining the height profile data from the transverse slope data or distance data, are known from the prior art. This 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:

1

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

2

a simplified perspective view of a road finisher and

3

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

1 shows a side view of a self-propelled road milling machine for milling off road surfaces in a simplified representation. The road milling machine 1 has a machine frame 3 supported by a chassis 2 . The chassis 2 of the milling machine includes front and rear crawler tracks 4 and 5, which are arranged on the right and left sides of the machine frame 3 in the working direction A. Wheels can also be provided instead of chain drives.

To adjust the height and/or inclination of the machine frame 3 relative to the surface of the ground 6, the road milling machine has a lifting device 7, which includes lifting columns 8 and 9 assigned to the individual crawler tracks 4, 5, 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 crawler tracks 4, 5 in a milling drum housing 11, which is closed on the long sides by a left and right edge protection 12. A conveyor device 13 with a conveyor belt 14 is provided for transporting away the milled road surface. The conveyor device 13 is arranged at the rear end of the road milling machine, viewed in the working direction A, so that the milled material can be loaded from the road milling machine driving ahead onto a subsequent road finisher. The driver's platform 15 for the machine operator is located on the machine frame 3 above the milling drum housing 11 .

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 relative to the ground surface 6 can be adjusted. In principle, however, it is also possible to change the height and inclination of the milling drum relative to the fixed machine frame.

2 shows a simplified perspective view of a self-propelled road finisher 16. The road finisher has a machine frame 18 carried by crawler tracks 17 (crawler finisher). Instead of chain drives, wheels can also be provided (wheel pavers). A storage container 19 for receiving the material to be paved is arranged in a front region of the machine frame 18 in the working direction A. At the rear of the road finisher 16 is a screed 20 for paving the material. The driver's stand 21 is arranged between the storage container 19 and the screed 20 .

The paving screed 20 is designed as a screed floating on the material to be paved. 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 road finisher 16 has a leveling device 23 ( 3 ) to compensate for short and long stretches of unevenness in the subsoil, so that a roadway can be paved with the desired evenness and installation thickness. The leveling device 23 has actuators 24 for changing the position of the screed 20 and a control unit 23A ( 3 ), which generates control signals for driving 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 traction point. To adjust the screed traction point, the actuators 24 of the leveling device 23 can include leveling cylinders 26 provided on the sides of the machine frame 18 . The leveling cylinders 26 can be used to adjust not only the angle of attack of the screed 20, but also the inclination of the screed transversely to the production direction A.

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

The road milling machine 1 of 1 and the paver 16 of 2 are operated according to the invention as a machine train, with the preceding road milling machine 1 supplying the height profile data from which the height profile data set for the leveling device 23 of the following road finisher 16 is obtained.

Below, with reference to 3 described in detail how the height profile data is determined by the road milling machine 1 and the height profile data set is obtained from the height profile data. 3 shows the machine train consisting of road milling machine 1 and road finisher 16 with the components essential 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 finisher 16 . The road milling machine 1 has a data transmission device 27 for transmitting the height profile data and the road finisher 16 has a data receiving device 28 for receiving the height profile data. The data transmission device and the data receiving 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 installed again as a new surface with the road finisher 16 .

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

In 3 the original profile is shown in the middle of the road (central gradient) and in the area of the right roadside (outer gradient). The middle gradient 29 shows essentially no depressions or elevations. However, depressions 31 or elevations can be clearly seen on the outer gradient 30 . The height of the roadway along a line in the longitudinal direction of the roadway, ie the central or outer gradient, is plotted on the Y-axis, and the distance is plotted on the X-axis. Δz _n denotes the vertical distance between the middle 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 middle gradient 29 and the outer gradient 30 at waypoint a ₁ . The road is inclined towards the edge by the angle α. The angle α is dependent on the horizontal distance and the vertical distance Δz _n between the middle gradient 29 and the outer gradient 30. Since the horizontal distance between the middle gradient 29 and the outer gradient 30 is known and remains constant during tillage, the angle α is at waypoint a _n suitable for determining 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 of a reference point on the road milling machine 1 to the surface of the unprocessed soil on the left-hand side of the milling drum 10 in working direction A and /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-hand side of the milling drum 10 in working direction A.

In order 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 processed with the milling drum 10 represents a copy of the unprocessed surface, i.e. 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 milling depth is recorded 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 determines a different milling depth, a corresponding correction is made. For example, there is a deepening at the edge of the road present, this is compensated for by the milling depth being increased on this side of the machine frame 3 by the lifting columns 8, 9, for example piston-cylinder arrangements, being retracted on this side. If, on the other hand, there is an elevation 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 middle of the roadway is largely free of bumps, the result is that on the side of the machine frame facing the middle of the roadway, hardly any control interventions of the milling depth control are necessary. However, experience has shown that the edge area of a road in need of rehabilitation often has bumps (due to settlements in the verge area, uneven loads, etc.), so that control interventions are often necessary on the side of the machine facing the edge area.

Due to the control interventions of the milling depth control device 33, the transverse inclination of the machine frame 3 changes as the milling machine advances. The changing transverse 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 average gradient, i. H. the transverse inclination of the machine frame describes the height profile of the road surface at the edge of the roadway.

To measure the distance Δx between a reference point on the road milling machine and the road surface that is not being machined, 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 protection 12 of the milling machine, for example a cable 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 in such a way that the lifting columns 8, 9 are retracted or extended depending on the measurement signals in such a way that when the road milling machine is advanced, the milling depth on the left and right side of the milling drum 10 in the working direction is independent of the Condition of the ground surface is kept essentially constant. Such a milling depth control device is from DE 10 2006 020 293 A1 famous.

The road milling machine 1 also has a profile data determination device 36 which, in one variant of the disclosure, has a transverse inclination sensor 37 . The transverse inclination α of the machine frame 3 or the milling drum 10, which changes as a result of bumps in the ground, is detected by the transverse inclination sensor 37 during the advance of the road milling machine. Cross slope can be measured continuously during advance or at predetermined time intervals to generate elevation profile data. The height profile data can be, for example, the data from the transverse inclination sensor 37 read out at specific time intervals by the profile data determination device. From the data from the transverse inclination sensor 37, the profile data determination device 36 determines a sequence of height profile data _{(Δz 1 , Δz 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 positioning system (GPS) 38 which, at the times at which the data from the transverse inclination sensor 37 are read out, ie at the waypoints a ₁ , a ₂ , a ₃ .., at position data (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ) ... (xn, y _n ) to calculate from the height profile data (Δz ₁ , Δz ₂ , Δz ₃ ,..., Δz _n ) to determine spatial height profile data. The profile data determination device 36, which, during the feed of the milling machine, generates a sequence of height profile data _{(Δz 1 , Δz 2 , Δz 3 ,} . . . , Δz _n ), assigns the data determined with the GPS system (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ) ... ( x _n , y _n ) to. However, a distance counter can also be provided to determine the position data (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ) . . . (x _n , y _n ). The position data can also be calculated from the feed rate and the time required by the road milling machine 1 to reach a certain waypoint a ₁ , a ₂ , a ₃ . . .

A spatial elevation 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 road section, in particular along the outer 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 central gradient 29 is known, absolute _height profile data _{(z 1 , z 2 , z 3 ,} .. ., z _n ) and a space-related absolute height profile data set are calculated, which describes the absolute height profile in the longitudinal direction of a specific road section, in particular along the outer gradient.

An evaluation device 39 , which can be provided in the road milling machine 1 or the road finisher 16 , is provided to obtain the height profile data record. If the evaluation device 39 is provided in the road milling machine 1 , the data transmission device 27 is used to transmit the entire data set or part of the data set to the data receiving device 28 . 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 in such a way that the height profile data is evaluated using known statistical evaluation methods. In the present exemplary embodiment, the mean value can be formed from the measured transverse slopes. Furthermore, in the exemplary embodiment, it can be provided that before the averaging takes place, data lying outside predetermined limit ranges are discarded. In the case of these measured values, it is assumed that incorrect measurements are present, or that the measuring device does not measure the road surface itself, but rather objects lying on the road, for example larger stones.

The height profile data set can be used in the road finisher 16 to control the actuators 24 of the leveling device 23 of the road finisher 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 on the basis of the height profile data set. For example, the angle of attack and/or the transverse inclination of the screed 20 can be adjusted as a function of the height profile data. In the present exemplary embodiment, the transverse inclination of the screed 20 is changed as a function of the height profile in such a way that indentations on the right-hand side of the roadway are compensated for. In the case of a depression, for example, the inclination of the screed 20 is reduced so that a larger quantity of material is laid on the right-hand side. With a suitable evaluation algorithm, unevenness in the subsoil can be compensated for.

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 set, but only control instructions for the actuators, in particular to a data receiving device 28.

It is advantageous that the height profile data record determined with the road milling machine 1 driving ahead can include data over a larger section of the road without a large number of sensors being required to determine this data. A boom is also not required on the road finisher 16 for attaching a plurality of sensors, which would otherwise be essentially limited in terms of its spatial dimensions to the length of the finisher. 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 finisher 16 can, for example, have a general Processor, a digital signal processor (DSP) for continuous processing of digital signals, a microprocessor, an application-specific integrated circuit (ASIC), an integrated circuit (FPGA) consisting of logic elements or other integrated circuits (IC) or hardware components to have the control of the actors to execute. A data processing program (software) can run on the hardware components. A combination of the various components is also possible.

An embodiment according to the invention requires a milling depth control device known in the prior art for controlling the lifting columns 8, 9, which has a measuring device for measuring the distance between a reference point on the road milling machine and the surface of the unworked ground on only one of the two sides of the milling drum 10 having. In the present embodiment, a measuring device 33A is provided on the left side of the machine frame 3 only. The milling depth control device 33 is designed in such a way that the lifting columns 8, 9 are retracted and 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 is kept constant on the left side. In addition, a transverse inclination 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 transverse inclination of the machine frame 3 is kept essentially constant when the road milling machine is advanced, regardless of the condition of the ground surface, so that results in a specified transverse slope for the milled surface. However, this means that on the right side the same layer thickness is not always removed in the longitudinal direction, for example only a smaller layer thickness in the area of a depression and a layer thickness greater than the average layer thickness in the area of an increase. The transverse inclination 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 On the other 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 in such a way that the height profile data is obtained from the distance data from the second measuring device 33B. Such a milling depth control device, which has two measuring devices on the left and right side and a slope control for setting a specific slope, is from DE 10 2006 020 293 A1 famous.

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,

   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),

   characterised in that

   the milling machine comprises a milling depth control device (33) that is for controlling the lifting columns (8, 9) and comprises a measurement device (33A) for measuring the distance of a reference point on the road milling machine to the surface of the unprocessed ground on one of the two sides of the milling drum (10), wherein the milling depth control device is configured so that the lifting columns (8, 9) are controlled such that when the road milling machine advances, the milling depth on one of the two sides of the milling drum (10) is kept substantially constant, regardless of the condition of the ground surface, wherein a transverse incline control device (40) is provided that is configured so that the lifting columns (8, 9) are controlled such that the transverse incline of the machine frame (3) when the road milling machine advances is kept substantially constant, regardless of the condition of the ground surface, and

   a measurement device (33A, 33B) for measuring the distance of a reference point on the road milling machine to the surface of the unprocessed ground on the other side of the two sides of the milling drum (10) is provided, the measurement device generating a sequence of distance data, wherein the profile data determining device (36) is configured so that the height profile data is obtained from the distance 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 is determined while the road milling machine advances, and the height profile data is transmitted with a data transmission device (27) to the road finisher,

   characterised in that

   the distance of a reference point on the road milling machine to the surface of the unprocessed ground on one of the two sides of the milling drum (10) is measured, wherein the milling depth of the milling drum (10) is controlled such that when the road milling machine advances, the milling depth on one of the two sides of the milling drum is kept substantially constant, regardless of the condition of the ground surface, wherein a transverse incline control is provided that is configured so that the transverse incline of the machine frame (3) when the road milling machine advances is kept substantially constant, regardless of the condition of the ground surface, and wherein the distance of a reference point on the road milling machine to the surface of the unprocessed ground on the other side of the two sides of the milling drum is measured, and a sequence of distance data is generated, and the height profile data is obtained from the distance 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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