Road paving machine with compaction control

Abstract

To provide a road paving machine that automatically controls a target layer thickness.SOLUTION: A road paving machine 1 comprises a paving screed 11. The paving screed 11 comprises a tamper 21, and also comprises a GNSS receiver 13, a material conveyor 7, and an electronic control system 15 including a memory 17 and a data processor 19. The memory 17 stores digital structural data, a longitudinal section of the target height for a paved road surface 28, a target layer thickness dS of a pavement material 5, and, as necessary, a longitudinal section of the height for a road base 27. The electronic control system 15 is configured to automatically control compaction performance of the paving screed 11 as a function of the target layer thickness dS, and to pave the pavement material 5 relative to each local coordinate point that is determined by the GNSS receiver 13.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a road paver and a method of operating a road paver. [Background technology]

[0002] In road construction, workers often find that the road base, i.e. the substrate prepared for application to the road surface, still has irregularities. These irregularities must therefore be levelled when the road surface is paved in order to obtain a flat surface. For this purpose, it has been known up until now to control the levelling cylinder of the road paving machine by conventional levelling to vary the layer thickness of the road surface. In this way, depressions are levelled with a thicker layer of paving material and bumps are levelled with a thinner layer of paving material, so that an overall perfectly flat paved surface is paved. However, this has proven to be disadvantageous, since the compaction carried out by the roller following paving causes the unevenness of the paved surface to reappear. This is because, due to the compaction performance of the roller, a thicker layer will have a greater absolute reduction in the roller levelling dimension, i.e. in the layer thickness, than a thinner layer.

[0003] From the patent EP 0 699 633 it can be seen that the problem of larger roller levelling dimensions for thicker layers of material can be counteracted by making the thickness of the pavement material greater in the areas of depressions in the road base than in the areas of prominences in the road base, i.e. paving the road surface unevenly with the paving machine. For control purposes digital road base data are used. However, the described method has drawbacks such as the fact that it can be difficult to control the changes in the pavement height, especially when the road base height changes in short intervals. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent Application Publication No. 2010 / 0129152 Summary of the Invention [Problem to be solved by the invention]

[0005] It is an object of the present invention to provide a road paver with an improved control system and an improved method of operating a road paver.

[0006] This object is solved by a road paver with the features of claim 1 and by a method for operating a road paver with the features of claim 7. Advantageous further developments of the invention are presented in the dependent claims. [Means for solving the problem]

[0007] The road paver according to the invention comprises a paving screed, the paving screed comprising a tamper. The road paver further comprises a GNSS (Global Navigation Satellite System) receiver, a material handling device and an electronic control system having a memory and a data processing device. The memory comprises a digital construction Data, especially the road paving Face eye elevation difference Profile , the target layer thickness of the pavement material, and the road base, if necessary. Board height Profile The electronic control system stores 、G By NSS receiver measurement Each of the road paving machines local Pave paving material to coordinate points To achieve this, the compaction performance of the paving screed is automatically controlled in relation to the target layer thickness. The device is configured to:

[0008] In the case of an uneven road base, the target layer thickness can be varied so that a flat surface or a flat road surface is obtained. Here, the compaction performance of the paving screed can be controlled in such a way that where the road base is depressed, i.e. where a thicker layer needs to be paved, the material is paved with a higher degree of compaction than in areas where the road base is elevated and therefore has a smaller layer thickness. The degree of compaction is selected so that all areas are compressed with the same absolute value during the subsequent compaction by the roller, i.e. the roller leveling dimension is everywhere the same, i.e. proportionally speaking, areas with a larger layer thickness are compressed and compacted by the roller less than areas with a smaller layer thickness. This means that the material can be paved with a flat surface and the road surface descends to the same extent everywhere, so that uniformity is maintained during the subsequent compaction.

[0009] Preferably, each local Coordinate points Reserve The degree of compaction is stored in the memory of the electronic control system, which means that the value does not have to be calculated first and the corresponding control signals can be sent directly to the components of the road paver that are relevant for setting the degree of compaction.

[0010] In a variant of implementation, the road paver is equipped with a sensor for measuring the actual layer thickness of the paving material, and the control system is configured to calculate the deviation of the actual layer thickness from the target layer thickness. A feedback mechanism makes it possible to pave the paving material precisely to the desired target layer thickness, i.e. until the deviation between the actual layer thickness and the target layer thickness is zero. Ultrasonic sensors, mechanical tactile sensors, laser sensors or other suitable sensors operating with or without an external reference point can be used for this purpose.

[0011] Preferably, the electronic control system is configured to automatically adjust the compaction performance of the paving screed by controlling the tamper frequency and / or the tamper stroke. The tamper tamps the mix below the paving screed, thus securing a sufficient amount of paving material to compact it.

[0012] In an advantageous variant, the paving screed comprises a screed plate and / or a pressure bar, and the electronic control system is configured to automatically regulate the compaction performance of the paving screed by controlling the vibration frequency and / or amplitude of the screed plate and / or the pressure of the pressure bar. These devices make it possible to achieve high compaction levels.

[0013] In another variant, the electronic control system is configured to automatically regulate the compaction performance of the paving screed by controlling the paving speed, which determines the duration of action of the tampers, screed plates and pressure bars of the compaction unit and is particularly suited to adapt the set values ​​to the required paving width.

[0014] A method according to the invention for operating a road paver, in particular a road paver according to one of the above embodiments, comprising the steps of: construction Data, especially road Board height Profile storing the digital signal in a memory of the electronic control system; construction Data, especially shape The road to be completed Face eye elevation difference Profile and Road infrastructure local coordinate points storing a target layer thickness of paving material; and paving the paving material, the current position of the road paver being determined based on the current position of the road paver. but By GNSS receiver Measured , Electronic control system , in order to pave the paving material at each precompaction degree, Compaction performance of paving screeds The eyes Mark thickness Depending on Automatically controlled do , and steps.

[0015] As mentioned above, this allows the paving material to have known properties that vary depending on the layer thickness. spare It is thus possible to pave with a degree of compaction. Thus, the loss of height due to subsequent compaction with the roller can be predicted, and the paving material can be paved with a layer thickness that is larger by the roller leveling dimension. This allows all localThe roller leveling dimensions are ensured to be the same for each coordinate point. local Not only the target layer thickness at the coordinate point or current position, but also the local Coordinate point, i.e., located further forward in the direction of travel local One or more target layer thicknesses of coordinate points can also be taken into account. Similarly, one or more past values ​​can also be used to ensure a continuous track of the ground surface.

[0016] Preferably, paving the paving material includes detecting the actual layer thickness by a sensor and calculating the difference between the actual layer thickness and the target layer thickness, and the road paver is automatically controlled to minimize said difference. Thus, the essential parameters of the paving operation, namely layer thickness and spare The degree of compaction can be automatically monitored and controlled, thus allowing the paver operator to devote more attention to other tasks performed in the paving operation. The current values ​​of the paving parameters, in particular layer thickness and spare It is envisaged that the degree of compaction is shown on a display so that the operator can read them and intervene in the automatic control system to change the parameters. As the progression of the target layer thickness, in particular the further values ​​at the current position and the degree of compaction along the pavement path, is known, the electronic control system automatically changes all the set values, with corrections usually only being made as part of an automatic feedback mechanism to reach the target value and prevent undesired deviations from it.

[0017] In an advantageous variant, the electronic control system automatically adjusts the compaction performance of the paving screed by controlling the tamper frequency and / or the tamper stroke. The tamper can be considered as the first stage of screed compaction. On the one hand, the tamper influences the amount of paving material passing under the screed. On the other hand, the tamper precompacts the paving material.

[0018] In another advantageous variant, the electronic control system automatically adjusts the compaction performance of the paving screed by controlling the vibration frequency and / or amplitude of the screed plate and / or the pressure of the pressure bars, so that a high degree of compaction can be achieved even with thicker layers.

[0019] In another variant, the electronic control system automatically adjusts the compaction performance of the paving screed by controlling the paving speed, which in particular can be adjusted in relation to the target layer thickness.

[0020] In the modified version at the time of implementation, Board height Profile Including digital construction The data is transmitted at the beginning of the procedure from an external data processing system to the memory of the electronic control system by wireless or cable connection. The external data processing system can be, for example, a laptop, a tablet, a mobile phone, a stationary personal computer, or a server, and the wireless transmission can be via RFID, Bluetooth, WLAN, or mobile phone connection, etc. In this way, it is possible to, for example, measure the surface temperature using an independent vehicle. of By scanning measurement The collected road infrastructure data can be supplemented with analysis, processing, and calculation data derived therefrom, which can be performed, for example, at a central location for monitoring the construction site, and then the data can be transmitted to road paving machines at the construction site.

[0021] In a preferred variant, an external data processing system depending on the specified target layer thickness Each compaction performance of calculation death , and / or their respective compaction performance of Target layer thickness Depending on the local Assign to coordinate point Used to The data is then sent to the memory of the electronic control system. 、 And ultimately, spareCompaction may be calculated continuously or obtained from a tabular data record. Calculation by an external system has the advantage that the necessary equipment can be easily provided and the data can be displayed, analyzed and processed by suitable Electronic Data Processing (EDP) equipment.

[0022] In a further variation, the electronic control system comprises: identification Depending on the target layer thickness, Teso Calculate the compaction performance of each layer and / or calculate the compaction performance of each layer according to the target layer thickness. local The data is assigned to coordinate points. In this way, these and other calculations can be performed directly on the road paver. The calculations can also be performed during the operation on the previous position, thus saving time. In addition, transmission capacity is saved as the amount of data received from the external source is smaller. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a schematic side view of a road paver. [Diagram 2] A three-dimensional view of construction data. [Diagram 3] FIG. 1 is a schematic diagram of compaction of a screed of paving material on a flat road base. [Figure 4] FIG. 1 is a schematic diagram of a roller compacting paving material on a flat road base. [Diagram 5] 1 is a graph showing the change in compaction by a paving screed as a function of layer thickness at constant roller leveling dimensions. [Figure 6] FIG. 1 is a schematic diagram of screed compaction of paving material on an uneven road base. [Figure 7] FIG. 1 is a schematic diagram of a roller compacting paving material on an uneven road base. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] In the following, embodiments of the invention will be explained in more detail with the aid of the drawings, in which corresponding components are provided with the same reference numerals.

[0025] Figure 1 shows a schematic side view of a road paver 1, where in the lower area in cross section a hopper 3 with paving material 5 is shown, which is transported by a material handling device 7 through a tunnel 9 to the rear in front of the paving screed 11 and evenly distributed by an auger 12. The road paver 1 also comprises a GNSS receiver 13 connected to an electronic control system 15. The electronic control system 15 comprises a memory 17 and a data processing device 19. The paving screed 11 comprises a tamper 21, a screed plate 23 and a pressure bar 25, where there may be several of these components.

[0026] The paving material 5 is pre-compacted by the paving screed 11 and in an ideal operation has a target layer thickness d S The layer thickness d corresponds to B The road surface 28 is paved on the road base 27, where the target layer thickness d S is the desired final layer thickness d that exists after the next compaction by the roller E The actual layer thickness d of the paving material 5 is higher by a certain roller leveling dimension s. I To measure the actual layer thickness d during the paving operation, a sensor 29 is used which can be mounted on the paving screed 11 or on the chassis of the road paving machine 1. I , which allows the paving screed 11 to be readjusted. An external data processing system 31, which may for example be provided with a laptop computer, is able to transmit and receive construction data by wireless link or via a cable connection 35 via an antenna 33 on the road paver 1 and on the data processing system 31, which antenna 33 may also be suitable for receiving satellite signals for position determination.

[0027] Figure 2 shows the digital construction A three-dimensional view of the data 37. The road infrastructure 27 is localCoordinate point 41 of Including height data Mutaka difference Profile 39. This height Profile 39 can be obtained by a prior scan of the ground surface using an external vehicle. However, a scanning device can be attached to the road paving machine 1 itself, and a scan of the ground surface can be performed on a part of the road base 27 further ahead in the direction of travel, while the already obtained digital construction The paving material 5 can also be laid on the rear based on the data 37. of 7 height Profile 39 data is paving road paving 2 of 8 eye elevation In this way, the road infrastructure 2 of 7 height Profile Depending on the bumps and depressions in 39, different target layer thicknesses d S Each local The coordinate points 41 are stored. local The number of coordinate points 41, at which the road infrastructure and surface data are stored, can vary depending on the technical specifications for data collection and processing, e.g. the accuracy of the GNSS, and is thus expressed in the form of a "resolution". construction It is also envisaged that the processing of the data 37 will include algorithms to distinguish areas of high frequency and / or more irregularities in the road base 27 from areas of less variation and to adjust the number of data points proportionately, thereby maintaining a high information density on the one hand and reducing the amount of data on the other hand. The position of the data points 41 in the grid may be influenced by the sensor position. Digital construction Data 37 is especially Road Infrastructure 2 of 7 height Profile Based on measurement data such as 39 Plan including further data to be calculated, data teeth, local The desired degree of compaction for each coordinate point 41, etc.

[0028] 3 is a schematic diagram of the compaction of a screed of paving material 5 on a flat road base 27. The paving material 5 is compacted to a bulk density ρ S The paving screed 11, which is pulled by the road paving machine 1 in the direction of travel F, deposits the paving material 5 at a bulk density ρ S , and the target layer thickness d for screed paving S The layer thickness d is equal to B 1 and compacting the pavement surface 28, thus paving the road surface 28. In the case of a flat road base 27, the paving screed 11 can be used without significant changes to the paving parameters once set.

[0029] FIG. 4 shows a schematic diagram of roller compaction of a paving material 5 or road surface 28 on a flat road base 27 to be paved by a paving screed 11. The layer thickness d B is reduced by the roller smoothing dimension s to the final layer thickness d E Therefore, the roller 45 must make one or more passes. The density of the paving material 5 is the roller-leveled density ρ W The degree of compaction can therefore be determined for the paving screed 11 and for the roller 45.

number

[0030] In the formula, ρ M is the density of the Marshall specimen, which is obtained under laboratory conditions using a compaction instrument. M corresponds substantially to the maximum density of the pavement material 5. That is, the degree of compaction k B , k W is the maximum density ρ of the paving material 5 provided by the respective machine, i.e. the paving screed 11 or the roller 45 M Represents the percentage of.

[0031] Figure 5 shows the relationship between the At a constant roller smoothing dimension s Paving Screed 11 Layer thickness d B In response to Compaction degree k B The change in , Equation 1 is derived as follows:

[0032] generally,

number

[0033] moreover,

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[0034] As a result, after the final compaction of the road surface by the roller, the degree of compaction of the road surface k B With respect to material density ρ W is the Marshallian density ρ M Assuming that it corresponds roughly to

number

[0035]

number

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[0036] Layer thickness d B is determined in advance and varies due to the unevenness of the road base 27. B is the total thickness of all layers d B 5. In order to obtain the same roller smoothing dimension s for all three axes, i.e. to stay on the corresponding function curve in FIG. 5 (s=10 mm, 20 mm, 30 mm), the rollers must be adjusted according to FIG.

[0037] Figure 6 shows a schematic diagram of the compaction of a screed of paving material 5 on an uneven road base 27. B1 and d B2 are specified at the desired level to obtain a flat road pavement 28. The roller leveling dimension s, which reduces the height of the road surface 28 by roller leveling compaction, is intentionally taken into account. B1 and k B2 is calculated by Equation 1. The electronic control system 15 can control the compaction performance of the paving screed 11 by activating one or more compaction units 21, 23 and 25, thus obtaining from the three-dimensional construction data 37 the respective calculated compaction degrees k at known points. B In order to achieve a constant roller levelling dimension s anywhere during the subsequent compaction by the roller 45, the compaction ratio k B And the layer thickness d B The density ρ depends on B It will be paved with

[0038] FIG. 7 shows a schematic diagram of a roller compacting a pavement material 5 on an uneven road base 27. The roller leveling dimension s is the degree of compaction k B1 , k B2 The road surface 28 already paved by the paving screed 11 is thus compacted by the roller 45 while maintaining its longitudinal flatness. After compaction by the roller, the road surface 28 has a uniform density ρ W , uniform compaction degree k W , and the final layer thickness d which varies according to the road base 27 E It becomes.

Claims

1. A road paving machine (1) comprising a paving screed (11), The paving screed (11) comprises a tamper (21), a GNSS receiver (13), a material handling device (7), and an electronic control system (15) having a memory (17) and a data processing device (19); In said memory (17) digital construction data (37) are stored, comprising a target height profile (43) of the road surface (28) to be formed, a target layer thickness (ds) of the paving material (5), a degree of precompaction (k B ) according to the target layer thickness (ds) for each local coordinate point (41), and, if necessary, a height profile (39) of the road base (27); 13. A road paver, comprising: a road paver for paving a paving material having a surface area of ​​100 m2 and a paving screed for paving the paving material; a road paver for paving a paving material having a surface area of ​​100 m2 and a paving screed for paving the paving material;

2. The actual layer thickness (d Ｉ ), and the electronic control system (15) further comprises a sensor (29) for measuring the target layer thickness (d Ｓ ) from the actual layer thickness (d Ｉ 2. The road paver of claim 1, configured to calculate a deviation of

3. 3. The road paver according to claim 1 or 2, characterized in that the electronic control system (15) is configured to automatically adjust the compaction performance of the paving screed (11) by controlling the tamper frequency and / or the tamper stroke.

4. 4. The road paving machine according to claim 1, wherein the paving screed (11) further comprises a screed plate (23) and / or a pressure bar (25), and the electronic control system (15) is configured to automatically adjust the compaction performance of the paving screed (11) by controlling at least one of the vibration frequency and amplitude of the screed plate (23) and / or the pressure of the pressure bar.

5. A road paver according to any one of claims 1 to 4, characterized in that the electronic control system (15) is configured to automatically regulate the compaction performance of the paving screed (11) by controlling the paving speed.

6. A method for operating a road paver (1) according to any one of claims 1 to 5, comprising: storing digital construction data (37) representing a height profile (39) of the road base (27) in a memory (17) of the electronic control system (15); The target height profile (43) of the road surface (28) to be formed, the target layer thickness (d Ｓ ), and storing digital construction data (37) including the degree of precompaction (k B ) according to the target layer thickness (ds); In a step of paving the paving material (5), the current position of the road paving machine (1) is measured by a GNSS receiver (13), and the electronic control system (15) adjusts the compaction performance of the paving screed (11) to a target layer thickness (ds) in order to pave the paving material (5) with a respective precompaction degree (kB) according to the target layer thickness (ds). Ｓ ) automatically controlling the temperature of the battery according to the temperature of the battery; A method comprising:

7. The paving of the paving material (5) is carried out by a sensor (29) to measure the actual layer thickness (d Ｉ ) and detecting the actual layer thickness (d Ｉ ) and the target layer thickness (d Ｓ 7. The method according to claim 6, characterized in that the difference between the measured value and the measured value is calculated and the road paver (1) is automatically controlled to minimize said difference.

8. 8. The method according to claim 6 or 7, characterized in that the electronic control system (15) automatically adjusts the compaction performance of the paving screed (11) by controlling the tamper frequency and / or the tamper stroke.

9. The method according to any one of claims 6 to 8, characterized in that the electronic control system (15) automatically adjusts the compaction performance of the paving screed (11) by controlling the vibration frequency and / or amplitude of the screed plate (23) and / or the pressure of the pressure bars.

10. The method according to any one of claims 6 to 9, characterized in that the electronic control system (15) automatically regulates the compaction performance of the paving screed (11) by controlling the paving speed.

11. The method according to any one of claims 6 to 10, characterized in that digital construction data (37), including a height profile (39) of the road base (27), are initially transmitted from an external data processing system (31) to a memory (17) of the electronic control system (15) by means of a wireless connection (33) or a cable connection (35).

12. The external data processing system (31) calculates the compaction performance of each layer based on the specified target layer thickness (d Ｓ ) and / or the respective compaction performances are calculated according to the target layer thickness (d Ｓ 12. The method according to claim 6, wherein the digital construction data (37) is assigned to a local coordinate point (41) according to the coordinates of the workpiece (10) and then the digital construction data (37) is transmitted to the memory (17) of the electronic control system (15).

13. The electronic control system (15) determines the respective compaction performance in accordance with the specified target layer thickness (d Ｓ ) and / or the respective compaction performances are calculated according to the target layer thickness (d Ｓ 12. The method according to claim 6, wherein the local coordinate points (41) are assigned according to

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