EP2392731B1 - Street construction machine and method for controlling the distance of a street construction machine moving on a ground surface - Google Patents

Description

The invention relates to a road construction machine according to the preamble of claim 1, and a method for controlling the distance of the machine frame of a road construction machine from a ground surface according to the preamble of claim 13.

Such road construction machines, in particular road milling machines or recyclers, require a level reference for processing a ground surface or a road surface in order not to duplicate the existing unevenness of the ground surface when machining the ground or road surface. Rather, unevenness and ripples should largely be compensated by the machining process. Without a reference value for the height adjustment of the machine frame or the working tool, the worst case result would take over any unevenness and waviness and skew, whereby subsequent machines e.g. Asphalting machines or compaction rollers have increased difficulties to produce a flat, homogeneously compacted road surface.

The road construction machine has a machine frame supported by a chassis in a plane with the landing gear moving on a ground or road surface. The chassis carries the machine frame via at least three lifting columns (in the case of small milling machines, only at least two lifting columns on the rear axle), which constitute a height adjustment device for the machine frame and which also adjust the plane of the machine frame in response to control signals of a leveling device with respect to a bank. The leveling device controls the distance between the machine frame and the currently crossed ground surface. For this purpose, it is already known that the bottom surface is scanned on laterally adjacent to a work roll side plates, or that along the driveway of the road construction machine, a wire is stretched, which can be scanned by the machine.

For machines with work rolls rigidly mounted in the machine frame, the distance can be measured relative to the machine frame.

For machines in which the work roll is adjustable relative to the machine frame, in addition, the distance of the work roll must be taken into account by the machine frame.

An advantageous reference location in the case of a road surface is often found in the middle of the road, since the road there has hardly any damage, displacements or other bumps.

It is already known in this regard to move a car next to the road construction machine along the middle of the road, which is connected via a telescope with the road construction machine. The telescope is used to set a different lateral distance of the car. At the free end of the telescopic rod is a displacement sensor, which detects the distance of the telescopic rod relative to the ground or road surface. In this telescope solution is advantageous that when processing a second working or milling track, the same reference location can be used next to or on the street center line. In this context is also on the DE3827617A1 to refer. A disadvantage of this solution is that a relevant deformation of the telescopic boom can not be excluded by the wide cantilever of the telescopic boom, so that the distance measurement can be falsified thereby. The invention is based on the object, a road construction machine of the type mentioned or a method for controlling the distance of a road-building machine to provide a soil surface in which the distance measurement with increased accuracy and with a higher reproducibility, as well as with less equipment is feasible.

To solve this problem serve the features of claim 1 and 13, respectively.

By directing a measurement beam representing a reference plane to a receiver spaced from the transmitter, the distance from the ground surface to the reference plane can be measured with high accuracy and reproducibility without requiring a mechanism that synchronizes the receiver or transmitter synchronously with the receiver Road construction machine moves, can have an impact on the measurement result. Before starting work, the measuring device can be calibrated.

The detected distance signal can therefore control the distance of the machine frame to the ground surface directly via the leveling device.

It is provided that the transmitter or the receiver is movable at a predeterminable distance laterally from the machine frame on the ground surface along a progressive reference location.

The predeterminable lateral distance from the road construction machine or the machine frame serves to fix the position of the reference location co-moving with the road construction machine, for example, along a road center line. If there are several tracks of work, it is possible to perform the scanning by the receiver at the same reference location that underlies the processing of the first working track.

It is preferably provided that a work roll is mounted in the machine frame and that the transmitter or the receiver is arranged in a plane extending substantially orthogonal to the reference plane, which also extends through the axis of rotation of the work roll.

The arrangement of the transmitter or the receiver in a common substantially vertical plane with the work roll axis of the measured Distance value can be used in the form of a measurement signal without conversion by the leveling device to perform a distance control of the machine frame and thus the work roll.

If the reference location in relation to the axis of rotation of the work roll in the direction of travel in front of or behind the axis of rotation, a conversion is required, which takes into account a skew of the machine frame in the longitudinal direction relative to the direction of travel.

It is preferably provided that the transmitter or the receiver is arranged on a carriage which is movable in synchronism with the machine frame in the direction of travel along the reference location on the ground surface.

The transmitter or the receiver is arranged on a carriage preferably provided with rollers, which passes over the reference location.

In this case, the receiver extends over a sufficient height in relation to the reference plane in order to detect the position of the reference plane can.

The transmitter or the receiver is arranged on a carriage, which is attached via a laterally to the machine frame telescopic coupling element hinged to the machine frame. For example, at least two spaced-apart joints may be provided, whose axes are parallel to the direction of travel or parallel to Fräswalzenachse.

The receiver may have a plurality of orthogonal to the ground surface at the reference location or to the machine frame arranged sensors that can measure the position of the reference plane. The sensors are arranged, for example, on a carriage such that they are orthogonal to the bottom surface on which the carriage rolls. Alternatively, sensors disposed on the machine frame are orthogonal to a plane parallel to the machine frame. The sensors are lined up with each other, wherein the distance of the sensors determines the resolution of the measurement. For example, the sensors are photosensitive sensors that can detect a reference plane formed of light.

The receiver may also include a plurality of orthogonal and parallel to the respective planes extending sensors that measure the position of the reference plane in terms of distance and inclination.

It is thus possible, for example, with the arrangement of a plurality of sensors in a plane parallel to the ground surface, in addition to the distance, to measure the instantaneous inclination of the reference plane to the instantaneous reference location. In this way, it is not only possible to control the distance of the machine frame and thus of the working tool at the level of the work roll, but also to control the height adjustment so that the machine frame is parallel to the current reference location.

It is preferably provided that the transmitter transmits measurement beams in the form of coherent light in a linear, sector-shaped or at an angle up to 360 ° and the reference plane is formed by this light detectable by the receiver.

In a particularly preferred embodiment, it is provided that a transmitter on the machine frame spans a reference plane which runs parallel to the machine frame, that a receiver extending substantially in the orthogonal direction to the bottom surface at the reference location up to the reference plane parallel to and synchronous with the machine frame is movable, which detects the distance of the reference plane to the current reference location.

Preferably, it is provided that the receiver has a transparent, extending up to the reference plane housing containing the sensors orthogonal to the bottom surface at the reference location in a linear array.

It can be provided that a plurality of sensors are arranged in a plane parallel to the bottom surface at the current reference location.

In a preferred embodiment it is provided that the reference location of the ground surface is located along a road centerline.

The transmitter is preferably arranged on the reference location facing side of the machine frame.

It can be provided that the distance of the supporting means of the carriage on the ground surface along the reference location is selected so that unevennesses of the reference location are compensated in the direction of travel. The carriage carrying the receiver preferably has a large center distance of the carriage wheels in the longitudinal direction, i. in the direction of travel. Instead of or in addition to the carriage wheels, other support means may also be provided, e.g. Skids, which are mounted laterally on the carriage and have a significantly greater length than the center distance of the carriage wheels. It is understood that the car can also have two carriage wheels side by side per axle.

Alternatively, the carriage may also be carried by the skids, or the carriage wheels may be disposed at the ends of the skids. In a further alternative, several carriage wheels are arranged, for example, at a small mutual distance in the direction of travel on the carriage or skids.

In a method for controlling the distance of the machine frame of a road construction machine moved on a ground surface to a reference location of the ground surface adjacent to the road construction machine in response to control signals of a leveling device, the distance of the machine frame to the ground surface is measured and the machine frame in an adjustable when passing over the ground surface is held orthogonal distance to the reference location of the ground surface, it is provided that a plane parallel to the machine frame or to the ground surface at a reference location is represented by at least one measuring beam of a transmitter, the reference plane of a substantially orthogonal to the other to the Ground surface is detected at a reference location or to the machine frame parallel plane extending receiver and thus the distance of the Fräswalzenachse measured to the ground surface at the reference location becomes.

In particular, a parallel to the machine frame reference plane can be spanned and extending substantially in the orthogonal direction to the bottom surface at the reference location to over the reference plane receiver at a predetermined distance laterally from the machine frame on the ground surface along the reference location, and parallel to and synchronously be moved with the machine frame, which detects the distance of the current reference location of the ground surface to the reference plane.

Preferably, it is provided that when commissioning the road construction machine, the current position of the reference plane is stored as the output value, from which deviations of the distance of the reference plane are measured to the current reference location.

In the following, embodiments of the invention will be explained in more detail with reference to the drawings.

Fig. 1

eine Straßenbaumaschine, insbesondere eine Straßenfräsmaschine,

Fig. 2

eine schematische Draufsicht auf eine Bearbeitungssituation auf einer Straßenoberfläche,

Fig. 3

der erfindungsgemäße Empfänger auf einem Wagen,

Fig. 4

eine alternative Ausführungsform mit zwei Empfängern,

Fig. 5

einen Schnitt entlang der Linie V-V in Fig. 3, und

Fig. 6

ein weiteres alternatives Ausführungsbeispiel, das die Anordnung von Gleitkufen zeigt.

Show it:

Fig. 1

a road construction machine, in particular a road milling machine,

Fig. 2

a schematic plan view of a processing situation on a road surface,

Fig. 3

the receiver according to the invention on a carriage,

Fig. 4

an alternative embodiment with two receivers,

Fig. 5

a section along the line VV in Fig. 3 , and

Fig. 6

another alternative embodiment showing the arrangement of skids.

Fig. 1 shows a road construction machine 1 using the example of a road milling machine. The road construction machine 1 has a machine frame 2, which of a For example, consisting of crawler chassis 4 is worn, which is connected via at least three height adjustment devices 8 in the form of lifting columns with the machine frame 2. How out Fig. 2 it can be seen, four lifting columns are provided in the embodiment, with which the machine frame 2 can be brought into a predetermined plane, which preferably runs parallel to the bottom surface 6 on which the crawler tracks of the chassis 4 are. In the case of a horizontal bottom surface 6, the machine frame 2 would normally be oriented horizontally.

In the Fig. 1 shown road milling machine has a work roll 22 between the crawler tracks of the chassis 4.

The work roll 22 is a milling drum in the case of a road milling machine. Other types of road construction machine, the milling drum, for example, at the level of the rear crawler tracks or wheels of the chassis 4 have. Likewise, the transport means for removing the milled soil material at the front 7 or rear end of the road construction machine 1 may be arranged.

The road construction machine 1 has a leveling device 10 which receives a distance signal which is representative of the distance between the machine frame 2 and the ground surface 6, and controls the height adjustment devices 8 in dependence on this distance signal such that a predetermined distance of the machine frame 2 and thus also the Work roll 22 is maintained to the soil surface. For this purpose, the leveling device 10 has an input and operating device on the control station, and a transmitter 15 which emits a measuring beam 17 representative of a plane parallel to the plane of the machine frame 2. The measuring beam 17 is directed to a receiver 16, which scans the bottom surface 6 along a reference location 12, such that the distance of the plane parallel to the machine frame 2 reference plane 14 are detected to the reference location 12 by means of sensitive to the measuring beam 17 sensors 32 can.

The transmitter 15 can emit a single measuring beam 17, emit a plurality of juxtaposed, lying in the reference plane 14 measuring beams 17 or emitting sector-shaped measuring beams 17 in one plane up to a radiation of up to 360 °. The transmitter 15 may be attached at any position of the machine frame 2, which allows a clear line of sight to the receiver 16 and is therefore preferably mounted on the reference site 12 side facing the road construction machine 1 on the machine frame 2.

The receiver 16 is preferably moved on a carriage 26 along the reference location 12, the carriage 26 being articulated to the machine frame 2 via a coupling element 28 telescoping laterally from the machine frame 2 to the side.

For this purpose, at least two joints are provided between the carriage 26 and the machine frame 2, the axes of which preferably run parallel to the direction of travel 9 or parallel to the milling drum axis 23. In order to be able to measure inclination differences, for example between telescopic rod and the carriage 26 may also be provided a ball joint, in which case it must be ensured that the carriage follows the reference location 12.

The telescopic coupling element 28 serves to allow a variable lateral distance of the carriage 26 to the machine frame 2. When the road construction machine 1 has to be traversed in a plurality of lanes over the ground surface 6 on wide roads, the telescoping capability allows the same reference location 12 to be selected for each lane.

How out Fig. 2 As can be seen, the reference location 12 can run in the vicinity of the center of a lane width, since this location has the least damage, warping or ripples of the ground surface 6.

Fig. 2 shows an all-round radiation of the transmitter 15. Such radiation of the measuring beams 17 for mounting a reference plane 14 is for example advantageous if multiple receivers 16, for example, at the front and at the rear end of the road construction machine 1 are provided. A sector-by-sector radiation of the measuring beams 17 would already be sufficient, even at different lateral distances of the reference location 12 to the machine frame 2 to make a distance measurement can.

In extreme cases, a single measuring beam 17, for example a laser diode, is sufficient if the measuring beam 17 can be aligned with the receiver 16.

Fig. 3 shows an example of a receiver 16 disposed on a carriage 26 which is moved on carriage rollers 30 along the reference location 12 on the ground surface 6. The arrangement of the sensors 32 is shown schematically and in the simplest case is a linear arrangement of the sensors 32 orthogonal to the reference location 12 of the bottom surface 6. The reference plane 14 is indicated as a dashed line, wherein the measuring signal receiving sensor 32 is shown as a black dot. It is understood that the smaller the distance between the individual sensors 32, the better the resolution.

In the background, schematically illustrated as a circle, the work roll 22 to indicate that a preferred position of the receiver 16 in the orthogonal to the bottom surface 6 extending plane through the Fräswalzenachse 23 runs.

As already stated, two carriages 26 may also be provided at the front and at the rear end of the road construction machine 1. In this case, the measurement of the longitudinal inclination of the reference plane 14 is possible. In order to control the distance of the machine frame 2 at the level of the milling drum axis 23, the leveling device 10 must perform a conversion, which results from the geometric data of the road construction machine 1.

Fig. 4 shows a second embodiment in which two receivers 16 are arranged at a mutual distance on a carriage 26. The reference plane 14 is shown with a longitudinal inclination, which can be measured by means of the sensors 32 of the two receivers 16.

Fig. 5 shows a cross section through the embodiment of the Fig. 3 showing a possible arrangement of the sensors 32 in a ground-parallel arrangement. In the simplest embodiment is in the example made of Plexiglas housing 38 of the receiver 16 only one sensor 32 in a ground-parallel plane. Alternatively, however, a plurality of sensors 32 can be arranged in one plane. Fig. 5 for example, shows eight sensors 32.

If no inclinations are to be measured with the arrangement of the sensors 32, in each case only one sensor 32 can be activated in the plane which receives the strongest signal. However, the circular arrangement of the sensors 32 could also be used, in particular for larger dimensions of the only example circular housing 38 also to measure an inclination of the reference plane 14, both as a longitudinal and as a transverse inclination of the machine frame 2 of the road construction machine. 1

The prerequisite is that the carriage 26 is held parallel to the machine frame 2, but otherwise articulated to the machine frame 2, namely articulated about an axis parallel to the Fräswalzenachse 23 axis and articulated with respect to the Fräswalzenachse 23 orthogonal, in the direction of travel parallel axis.

Fig. 6 Finally, shows a further embodiment, which is provided with two receivers 16, but of course only a receiver 16 may have. In this embodiment, a skid 40 is provided on at least one side of the carriage 26, which has a length such that they can compensate for the longitudinal undulations of the soil surface at the reference location 12 better.

In another embodiment, not shown, the carriage wheels 30 may also be arranged at the ends of the skids 40.

The embodiments shown show the arrangement of the transmitter 15 on the machine frame and the arrangement of the receiver 16 on a movable carriage 26. It is understood that a reverse arrangement, namely the transmitter 15 on the movable carriage 26 and the receiver on the machine frame is possible. In this case, from the carriage 26 at a predetermined height, one or more measuring beams 17 would be directed toward the machine frame are emitted, wherein the sensors 32 of the receiver 16 are arranged at suitable locations orthogonal to the machine frame 2 parallel plane on the side surfaces of the road construction machine 1.

When clamping a radiated all around or radiated at least in the direction of the road construction machine 1 reference plane 14 is also possible to arrange two receiving devices at the front and at the rear end road construction machine 1, with which, for example, the longitudinal inclination of the road construction machine can be detected. If the receiving device has, in addition to the sensors 32 arranged orthogonally to the plane of the machine frame 2, sensors arranged parallel to the machine frame 2, it is also possible to measure a transverse inclination of the machine frame 2 in relation to the reference location 12 of the bottom surface 6.

It should be noted that the road construction machine 1 is operated predominantly with a predetermined bank in order to ensure the drainage of water at a newly created road surface.

Claims (15)

1. A road construction machine (1) with a machine frame (2) and a running gear (4) carrying the machine frame (2) in a single plane, said running gear (4) moving on a ground surface (6) in the direction of travel (9) and comprising height adjustment devices (8) for adjusting the position of the plane of the machine frame (2) in accordance with control signals of a levelling device (10), wherein the levelling device (10) is operative to measure the distance of the ground surface (6), at a current reference location (12) of the ground surface (6), to the machine frame (2), and to control the height adjustment devices (8) in such a manner that the plane of the machine frame (2) is movable at an adjusted orthogonal distance to the reference location (12) of the ground surface (6),
   characterized in that
   a transmitter (15) is arranged at the machine frame (2) in a rigid manner, and a receiver (16) is movable, parallel to and synchronously with the machine frame (2), next to the machine frame (2) along the current reference location (12), or
   a receiver (16) is arranged at the machine frame (2) in a rigid manner, and a transmitter (15) is movable, parallel to and synchronously with the machine frame (2), next to the machine frame (2) along the current reference location (12),
   wherein the transmitter (15) emits at least one measuring beam (17) representative of a reference plane (14), said measuring beam being detectable by the receiver (16) and representing either a plane extending parallel to the machine frame (2) or a plane extending parallel to the ground surface (6) at the reference location (12),
   wherein the current distance of the machine frame (2) to the current reference location (12) is measurable from the detected position of the reference plane (14).
2. The device in accordance with claim 1, characterized in that the transmitter (15) or the receiver (16) is movable, at a specifiable distance at the side of the machine frame (2), on the ground surface (6).
3. The device in accordance with claim 1 or 2, characterized in that a working drum (22) is mounted in the machine frame (2), and that the transmitter (15) or the receiver (16) is arranged in a plane which extends orthogonal to the reference plane (14), and which further essentially extends through the rotating axis (20) of the milling drum (22).
4. The device in accordance with claim 1 or 3, characterized in that the transmitter or receiver (16) is arranged on a carriage (26) which is movable, synchronously with the machine frame (2), in the direction of travel (9) on the ground surface (6).
5. The device in accordance with one of the claims 1 to 4, characterized in that the transmitter (15) or the receiver (16) is arranged on a carriage (26) which is attached, in an articulated fashion, to the machine frame (2) via a coupling element (28) telescoping laterally relative to the longitudinal direction of the machine frame (2).
6. The device in accordance with one of the claims 1 to 5, characterized in that the receiver (16) comprises a plurality of sensors (32) arranged orthogonal to the ground surface (6) at the reference location (12) or to the plane extending parallel to the machine frame (2), said sensors (32) measuring the distance of the reference plane (14) to the ground surface (6) at the reference location (12), and respectively to the plane extending parallel to the rotating axis (23) of the working drum.
7. The device in accordance with one of the claims 1 to 6, characterized in that the receiver (16) comprises a plurality of sensors (32) arranged orthogonal and parallel to the ground surface (6) at the reference location (12) and respectively to the plane extending parallel to the machine frame (2), said sensors (32) allowing a measurement in terms of distance and slope.
8. The device in accordance with one of the claims 1 to 7, characterized in that the transmitter (15) emits coherent light in a linear fashion, in a sector-shaped fashion or under an angle of up to 360 degrees, and that the reference plane (14) is formed by said light that is detectable by the re-eiver (16).
9. The device in accordance with one of the claims 1 to 8, characterized in that the receiver (16) comprises a transparent housing (38) extending to above the reference plane (14)
10. The device in accordance with one of the claims 1 to 9, characterized in that a transmitter (15) at the machine frame (2) defines a reference plane (14) of a plurality of measuring beams (17), said reference plane extending essentially parallel to the machine frame (2), that a receiver (16) extending in an essentially orthogonal direction to the ground surface (6) at the reference location (12) to above the reference plane (14) is movable parallel to and synchronously with the machine frame (2), said receiver (16) detecting the distance of the reference plane (14) to the current reference location (12) on the ground surface (6).
11. The device in accordance with one of the claims 1 to 10, characterized in that the reference location (12) of the ground surface (6) is located along a road centreline (36).
12. The device in accordance with one of the claims 1 to 11, characterized in that the distance of supporting means (30) of the carriage (26) on the ground surface (6) along the reference location (12) is chosen so as to level out any irregularities of the reference location (12) in the direction of movement.
13. A method for controlling the distance of the machine frame (2) of a road construction machine (1) moved on a ground surface (6) to a reference location (12) of the ground surface (6) next to the road construction machine (1) in accordance with control signals of a levelling device (10), wherein the distance of the machine frame (2) to the ground surface (6) is measured at a reference location (12), and the machine frame (2), when travelling over the ground surface (6), is maintained at an adjustable orthogonal distance to a reference location (12) of the ground surface (6),
    characterized in that
    a reference plane (14) extending parallel to the machine frame (2) or to the ground surface (6) at a reference location (12) is represented by at least one measuring beam (17) of a transmitter (15), wherein the reference plane (14) is detected by a receiver (16) extending essentially orthogonal to the respective other plane extending parallel to the ground surface (6) at a reference location (12) or to the machine frame (2), thus measuring the distance of the machine frame (2) to the ground surface (6) at the reference location (12).
14. The method in accordance with claim 13, characterized in that a reference plane (14) extending parallel to the machine frame (2) is defined, and that a receiver (16) extending in an essentially orthogonal direction to the ground surface (6) at the reference location (12) to above the reference plane (14) is moved, at a specifiable distance at the side of the machine frame (2), along the reference location (12) on the ground surface (6), as well as parallel to and synchronously with the machine frame (2), said receiver (16) detecting the distance of the current reference location (12) of the ground surface (12) to the reference plane (14).
15. The method in accordance with claim 13 or 14, characterized in that, when the road construction machine (1) is started up, the current position of the reference plane (14) is saved as default value, starting from which any deviations in the distance of the reference plane (14) to the current reference location (12) are measured.

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