EP3040478B1 - Self-propelled street milling machine for milling street surfaces, and method for machining street surfaces with a street milling machine - Google Patents

Description

The invention relates to a self-propelled road milling machine for machining road surfaces according to the preamble of claim 1 and a method for machining road surfaces according to the preamble of claim 14.

Such road milling machines are already known in principle. In small milling machines, where the milling drum is at the height of the rear axle of the chassis and between the rear wheels, it is known to provide on the null side of the machine, a rear jockey wheel or track drive, which can swing inward for edge-near milling behind the outer contour of the road milling machine.

Large milling machines are, for example, road milling machines in which the milling drum is mounted on the machine frame between the crawler tracks of the front and rear axles, and at a distance therefrom. The EP 11 677 626 A1 describes such a large milling machine.

The milling rollers of such milling machines have a plurality of circumferentially preferably helically arranged tools. Usually, these are milling tools which are fixed in tool holders welded onto a hollow cylindrical roller body or in chisel holder systems. The tools therefore have a constant line spacing, which corresponds to the axial distance between adjacent tools and is usually between 3 mm and 25 mm.

Due to the axial spacing of the tools, a groove structure is produced on the milled surface during the milling process, with the mutual spacing of adjacent grooves corresponding to the line spacing.

The choice of the line spacing depends on the respective milling task. Thus, in the development of complete lanes usually a larger line spacing is selected than in fine milling, which only serves the roughening of the road surface with low milling depth.

In simple terms, this is due to the fact that milling drums with small line spacing are not suitable for large cutting depths due to the high tool density, while milling drums with large line spacing do not achieve the desired structure for roughening the roadway because the groove structure produced in the milled surface is too coarse.

In addition to milling depth and desired surface structure also play a variety of other factors, such as the type of substrate to be processed for the choice of line spacing a role, which means that a variety of different milling drums with different line spacing for different tasks are available.

As a result, it is necessary for milling contractors to provide different milling machines for different tasks and / or different milling drum types for a milling machine.

This results in additional costs for the purchase of additional machinery, or additional labor and time required for the conversion of the machines different milling drums. In particular, this is disadvantageous when various requirements must be met on a construction site and therefore different machines are transported to the place of use, or a machine has to be converted on site.

The invention is therefore an object of the invention to provide a road milling machine for processing road surfaces, as well as a method for editing road surfaces that allow flexible use for various milling tasks, expand the possibilities of milling, and can be used cost and time saving.

To solve this problem serve the features of claim 1 and 14th

The invention advantageously provides that an oscillation drive exerts on the milling drum an oscillation stroke reciprocating in the axial direction relative to the machine frame, the rotational movement of the tools being superimposed on an axial movement running parallel to the axis of the milling drum whose stroke is at the line spacing is adaptable between two axially adjacent tools.

The advantage of the invention is that with a single roughing or standard roll now large cutting depths can be achieved and at the same time fine surface structures are produced.

By virtue of the fact that the milling drum exerts an oscillation stroke reciprocating in the axial direction relative to the machine frame, the line structure on the road surface can be changed or completely eliminated. As a result, a road surface can be achieved with a structure that is not directly dependent on the line spacing of the milling drum. It also eliminates the need to use a milling drum, which produces a finer line structure on the milled surface. Another advantage is that the changed surface structure of the road surface can be achieved even with larger cutting depths. The tools perform a rotational movement about the Fräswalzenachse, which is superimposed by an axial movement parallel to the axis of the milling drum. The stroke of the displacement of the milling drum in the axial direction can be adjusted according to the line spacing of two axially adjacent tools, so that the oscillation is variably variable on milling drums with different tool density. This eliminates changeover times and the provision of a variety of milling drums for different applications can be significantly reduced.

In particular, can be dispensed with by the axial oscillation on fine and Microfeinfräswalzen, which are costly due to the high tool density and high chisel wear per m ³ .

In this way, when using e.g. a standard milling of both the complete construction of roads and the removal of only a top layer of a road surface or an increase in grip by roughening are effectively performed.

The invention makes it possible to save time and costs in an advantageous manner, because both coarse structures and fine structures can be produced with a single milling drum.

In addition, advantages over milling with conventional fine milling rollers are achieved. The fine groove structure produced during fine milling can negatively influence the steering behavior, in particular of two-wheeled vehicles, and lead to self-steering behavior. By the oscillation of the milling drum, this groove formation is reduced parallel to the traffic lane, even if the oscillation stroke is smaller than the line spacing.

It is understood that the Oszillationshub does not have to correspond exactly to the line spacing, but also can be set lower or greater, or alternatively can be switched off completely, so that the road milling machine can be operated in a conventional manner.

It is preferably provided that the amplitude and / or the frequency of the oscillation are variably adjustable, so that the type of structure produced by the milling drum on the surface can be adapted individually to specific milling tasks.

In this case, the oscillation stroke in the range between 0.5 to 1.5 times, preferably between 0.9 to 1.1 times the line spacing can be adjusted. Alternatively, the oscillation stroke can be adjustable in the range between 3 mm and 40 mm.

The frequency of the oscillation can be adjustable, for example, between 0.1 and 20 Hz.

It can preferably be provided that the ratio of the average speed amount of the oscillation stroke to the peripheral speed of the milling drum tools lies in the range between 0.1 and 3, preferably between 0.25 and 2.

In one embodiment, it is provided that the milling drum has an axially movable axial bearing. The movable axial bearing can be achieved in that the milling drum housing is displaced together with the milling drum or that the axial bearing is axially movable relative to the Fräswalzengehäuses.

In a further embodiment, it may additionally be provided that a reciprocating movement in the direction of travel can be superimposed on the axial bearing. This means that the milling drum can oscillate both in the axial direction and in the direction of travel. For this purpose, a further oscillation drive is preferably provided. The displacement of the milling drum in the direction of travel can be done not only linearly but also arcuately about an axis extending above the milling drum parallel to the milling drum axis.

Preferably, a control is provided which automatically controls or regulates the oscillation frequency and / or the amplitude of the oscillation stroke as a function of the milling drum rotational speed and / or the feed rate and / or milling depth of the milling drum.

In a preferred embodiment it is provided that the milling drum oscillates together with the Fräswalzengehäuse in the axial direction, and that the Oscillation drive the Fräswalzengehäuse drives relative to the machine frame.

Alternatively, it may be provided that the oscillation drive drives the milling drum in the milling drum housing in the axial direction.

At the same time, the milling drum housing is longer in the axial direction than the milling drum at least by the maximum oscillation stroke.

Preferably, it is provided that the axial bearing is a fixed-lot storage, in which the fixed bearing is displaceable in the axial direction.

In this case, the oscillation drive can act on the side of the fixed bearing axially on a running in the Fräswalzenachse drive shaft of the milling drum.

The movable bearing allows for a movement stroke that corresponds at least to the oscillation stroke.

The milling drum may have a rotary drive which drives a drive shaft on the side of the fixed bearing. If the entire Fräswalzengehäuse can oscillate in the axial direction, this is done along at least two linear guides, which extend parallel to the Fräswalzenachse in the axial direction.

In all embodiments, it can be provided that the milling drum housing or the milling drum can be oscillated along at least two linear or arcuate guides in the direction of travel.

All guides have a first guide, which leads both vertically and horizontally, and at least one further, parallel to the first guide extending second guide, which leads at least in the horizontal direction.

In this way it is ensured that the guides do not clamp against each other.

The object is also achieved by the method according to claim 14, wherein during operation an oscillating oscillation stroke reciprocating in the axial direction is exerted on the milling drum in the axial direction, the rotational movement of the tools being superimposed on an axial rotational movement running parallel to the axis of the milling drum Hub is variably adjusted to the line spacing of two axially adjacent tools.

Preferably, it is provided that a milling drum rotational frequency in the range between 0.5 Hz and 3 Hz corresponding to a Fräswalzendrehzahl in the range of 30 U / min to 180 U / min, preferably between 1 Hz and 2.5 Hz or 60 U / min to 150 U / min, is combined with an oscillation frequency between 2 Hz and 40 Hz, preferably between 5 Hz and 15 Hz.

Alternatively, the Fräswalzendrehzahl in the range between 180 U / min and 600 U / min corresponding to a Fräswalzendrehfrequenz between 3 Hz and 10 Hz, preferably between 240 U / min and 360 rev / min or the Fräswalzendrehfrequenz between 4 Hz and 6 Hz and with an oscillation frequency of 0.1 Hz to 5 Hz, preferably between 1 Hz and 3 Hz, are combined.

In a further development of the method can be provided that is superimposed on the axial oscillation of the milling drum transversely to the direction of travel an oscillating movement in the direction of travel of the milling drum.

Exemplary embodiments of the invention will be explained in more detail below with reference to the drawings.

Fig. 1

eine perspektivische Ansicht einer Straßenfräsmaschine in Form einer Großfräse,

Fig. 2a

eine Fräswalze mit spiralförmig angeordneten Werkzeugen nach dem Stand der Technik,

Fig. 2b

die Struktur einer gefrästen Straßenoberfläche,

Fig. 2c

den Linienabstand der Werkzeuge,

Fig. 3

eine herkömmliche Lagerung der Fräswalze,

Fig. 4

ein erstes Ausführungsbeispiel der Erfindung,

Fig. 5

eine schematische Darstellung eines axial verschiebbaren Fräswalzengehäuses mit einer darin gelagerten Fräswalze gemäß Fig. 4 in Draufsicht,

Fig. 6

eine schematische Darstellung der Axialverschiebung der Fräswalze innerhalb des Fräswalzengehäuses gemäß einem zweiten Ausführungsbeispiel,

Fig. 7

eine schematische Darstellung der Linearverschiebung des Fräswalzengehäuses in Fahrtrichtung, und

Fig. 8

eine schematische Darstellung einer Linearverschiebung der Fräswalzenachse in Fahrtrichtung,

Fig. 9 und 10

eine schematische Darstellung einer Pendelbewegung des Fräswalzengehäuses bzw. der Fräswalze in Fahrtrichtung, und

Fig. 11

einen Querschnitt durch die Linearführungen.

Show it:

Fig. 1

a perspective view of a road milling machine in the form of a large milling machine,

Fig. 2a

a milling drum with spirally arranged tools according to the prior art,

Fig. 2b

the structure of a milled road surface,

Fig. 2c

the line spacing of the tools,

Fig. 3

a conventional mounting of the milling drum,

Fig. 4

a first embodiment of the invention,

Fig. 5

a schematic representation of an axially displaceable Fräswalzengehäuses with a milling drum mounted therein according to Fig. 4 in plan view,

Fig. 6

a schematic representation of the axial displacement of the milling drum within the Fräswalzengehäuses according to a second embodiment,

Fig. 7

a schematic representation of the linear displacement of the Fräswalzengehäuses in the direction of travel, and

Fig. 8

a schematic representation of a linear displacement of the Fräswalzenachse in the direction of travel,

FIGS. 9 and 10

a schematic representation of a pendulum movement of the milling drum housing or the milling drum in the direction of travel, and

Fig. 11

a cross section through the linear guides.

Fig. 1 shows a large milling machine as they basically from the EP 2 011 921 A is known. The road milling machine 1 has a machine frame 8, which is supported by a chassis with at least three crawler tracks 20 or wheels.

The milling drum housing 10 is arranged in the direction of travel 22 between the crawler tracks 20, in small milling, however, rather at the level of the rear support wheels or crawler tracks 20th

The milling drum 12 is rotatable about a Fräswalzenachse 24 transverse to the direction 22, wherein the milling drum 12 is mounted in side walls 11, 13 of the Fräswalzengehäuses 10 or on the machine frame 8.

The milling drum 12 may extend with its one end face to the outer side of the machine frame 8 designated as the zero side, whereas a drive device for the milling drum 12 may be arranged on the opposite outer wall of the machine frame 8. The drive device for the milling drum 12 may be, for example, a mechanical drive having a belt drive 38 or a hydraulic or electric drive.

Above the milling drum 12 is the driver's cab 14 with a seat for the driver.

Fig. 2a shows by way of example the arrangement of the tools 16 on the milling drum 12, as basically from the DE 102 03 732 is known. In the circumferential direction, the tools 16 have a predetermined predominantly constant mutual distance. At each end face of the milling drum 12, a series of tools 16 may be provided which are not spirally arranged to produce vertical milling edges. Since the tools 16 do not change their axial position during the rotation of the milling drum 12, they produce on the road surface 2 grooves 18 which form in the direction of travel 22 on the road surface 2 in cross-section groove-shaped recesses, as for example in the FIGS. 2b and 2c are recognizable.

The distance 19 between two adjacent grooves 18 is therefore dependent on the line spacing of the milling drum, that is, the axial distance of the circumferentially adjacent tools 16.

Depending on the milling drum structure, line spacings are preferably common between 3 mm and 25 mm.

Fig. 2c schematically shows the distance 19 between the grooves 18, which results from the line spacing of the spirally arranged on the milling drum 12 tools 16.

Preferably, two counter-rotating spirals of tools 16 are formed on the milling drum 12, which have the task to transport the milled material to the roll center or to a specific axial position of the milling drum 12.

Fig. 3 schematically shows a conventional axial bearing of a milling drum 12 in a Fräswalzengehäuse 10, which is immovable axially relative to the machine frame 8. The Fräswalzenachse 24 is mounted in the side walls 11, 13 of the Fräswalzengehäuses 10, with the aid of a fixed bearing 30 and a floating bearing 32. The floating bearing is axially movable to a small extent, so that, for example, thermal expansion of the Fräswalzenachse 24 can be compensated.

Preferably, on the side of the fixed bearing 30, the milling drum drive is usually arranged, which can be done for example by a mechanical belt drive 38 but also hydraulically or electrically.

The inventively mounted in the end walls of the Fräswalzengehäuses 10 milling drum 12 has apart from a radial bearing axially movable axial bearing. In this case, the fixed bearing (axial bearing) of the milling drum is moved relative to the machine frame 8, either with the entire Fräswalzengehäuse 10 or relative to this.

Due to the inventively relatively small oscillation stroke in this case also a mechanical roller drive can be realized, since only a small axial movement of the belt drive 38 must be made.

In Fig. 4 and 5 an embodiment is shown in which the axial movement of the milling drum is achieved in that the entire milling drum housing 10 with the milling drum 12 performs the Oszillationshub. In this case, the oscillation drive 28 acts between the milling drum 12 and the milling drum housing 10.

The milling drum housing 10 is, as in FIGS. 4 and 5 can be seen, along at least two linear mutually parallel guides 42a, 44a and 42b, 44b transversely to the direction of travel 22 movable to allow oscillation of the entire Fräswalzengehäuses 10 with the milling drum 12 in the axial direction parallel to the Fräswalzenachse 24 in a ground-parallel plane.

An oscillating drive 28, in particular a linear drive, e.g. from a piston-cylinder unit or a mechanical eccentric drive, or a spindle drive allows the oscillation of the milling drum housing 10 relative to the machine frame eighth

Fig. 5 is a schematic plan view of the embodiment of Fig. 4 , from which it can be seen that the linear guides 42a, 42b are parallel to the linear guides 44a and 44b and to the milling drum axis 24.

Since the milling drum housing 10 executes only a short stroke, the guides 42a, 42b, 44a, 44b can be made significantly shorter than in the schematic representation in FIG Fig. 5 , It is understood, furthermore, that each linear guide 42a, 42b and 44a, 44b may be made in one piece. This means that the guide elements 42a, 42b and 44a, 44b can be connected to one another or extend over the entire width of the milling drum housing 10.

Fig. 6 schematically shows a second embodiment in which the Fräswalzengehäuse 10 is rigidly fixed to the machine frame 8 and the milling drum 12 is mounted in the side walls 11, 13 via movable bearings 32a, 32b. The oscillation drive 28 acts between the milling drum 12 and the milling drum housing 10. For this purpose, the milling drum housing 10 is longer in the axial direction than the milling drum 12 by at least the maximum oscillation stroke.

Alternatively it can be arranged between the side wall 13 and the milling drum 12, a not shown axially movable partition, in which one end of the milling drum 12 is mounted in a fixed bearing. The oscillating drive 28 in this case acts between the intermediate wall and the side wall 13.

The Fig. 7 schematically shows the oscillating movement of the Fräswalzengehäuses 10 in the direction of travel 22, while Fig. 8 an embodiment in which the milling roller 12 can oscillate within the side walls 11, 13 in the direction of travel.

Through two more in Fig. 7 shown linear guides 46, 48 which are orthogonal to the linear guides 42, 44, a further oscillatory movement parallel to the direction of travel 22 can be generated, so that the rotational movement of the tools 16 can be superimposed not only an axial oscillatory motion, but also an additional oscillatory motion parallel to the direction of travel 22.

The Fräswalzenachse 24 is in the embodiment of Fig. 8 guided in the milling drum housing 10 in a horizontal slot 25.

The linear guides 42, 44, 46, 48 may for example also be provided in the manner of a cross slide.

The amplitude and / or the frequency of the oscillation in the axial direction and parallel to the direction of travel 22 are variably adjustable. For example, the oscillation stroke can be set in a range of 0.5 to 1.5 times the line spacing. Preferably, however, the maximum oscillation stroke is oriented at the line spacing and differs only slightly therefrom.

For example, the oscillation stroke in a range between 3 mm, preferably 5 mm, and 40 mm adjustable.

The frequency of the oscillation can be set between 0.1 Hz and 40 Hz.

Alternatively, the frequency may be adjusted to achieve a certain ratio of the average axial velocity amount to the feed rate of the milling drum 12 or the peripheral speed of the tools of the milling drum 12 or the addition of the peripheral speed of the tools and the feed rate of the milling machine.

According to a further alternative, the combination of a specific Fräswalzendrehzahlbereichs with an adapted range of the oscillation frequency may be advantageous.

For example, a relatively high milling roll speed in the range of 180 rpm to 600 rpm (or milling drum rotational frequency between 3 Hz to 10 Hz), preferably between 240 rpm to 360 rpm (or 4 Hz to 6 Hz) a relatively low oscillation frequency between 0.1 Hz to 5 Hz, more preferably between 1 Hz to 3 Hz, to be combined.

The oscillation frequencies refer to the specified range for the oscillation.

According to another particularly preferred embodiment, a low milling roll speed can be combined with a high oscillation speed.

In this case, the milling drum speed can range from 30 rpm to 180 rpm (corresponding to milling drum rotation frequency 0.5 Hz to 3 Hz), preferably between 60 rpm to 150 rpm (corresponding to 1 Hz to 2.5 Hz ), at an oscillation frequency in the range between 2 Hz to 40 Hz, preferably between 5 Hz to 15 Hz.

Basically, this embodiment is preferable because it allows lower tool wear to be achieved (lower peripheral speed of the bits, i.e. lower forces on the tool being cut).

The oscillation frequency should not correspond to an integer multiple of the rotational frequency of the milling drum (or vice versa), since thus the cut could be made each time in the same, running in the direction of travel line. However, this effect is negligible in the case of fast oscillation, eg five times the rolling rotational frequency.

In the case of an oscillation stroke corresponding to the line spacing, integer multiples of half the rotational frequency are also to be avoided, since otherwise the cut always takes place in the same line or the adjacent line of the line structure extending in the direction of travel.

Finally, a variable oscillation frequency is possible by superposition with a harmonic of the rotational frequency of the milling drum, e.g. with a bandwidth of 30% around the oscillation frequency.

The superimposed oscillating movement of the milling drum 12 parallel to the direction of travel 22 may also be linear instead of as in the FIGS. 7 and 8 illustrated, circular arc-shaped about a pivot axis 50 take place, which extends above and parallel to the Fräswalzenachse 24.

Fig. 9 shows an embodiment in which the milling drum housing 10 with the milling drum 12 about the pivot axis 50 in the direction of travel 22 can oscillate circular arc.

Fig. 10 shows an alternative embodiment in which the milling drum 12 can oscillate within the Fräswalzengehäuses 10 about the pivot axis 50 in the direction of travel 22. The slot 25 is curved in this case about the pivot axis 50 in the side walls 11 of the Fräswalzengehäuses 10 arranged curved.

Fig. 11 shows a cross section through the longitudinal guides 42, 44, 46, 48, from which it can be seen that in each case one of the two mutually parallel guides 42, 48 has only one degree of freedom, namely in the axial direction and the respective other guide 44, 46 a degree of freedom in axial direction and a degree of freedom in the horizontal direction. This design of the guides is suitable both for the linear guides 42, 44 acting in the axial direction and for the linear guides 46, 48 acting in the direction of travel.

The road milling machine may have a controller 14, the oscillation frequency and / or the amplitude of the oscillation depending on the Fräswalzendrehzahl and / or the feed rate of the milling machine and / or Cutting depth of the milling drum automatically controls or regulates. In addition, parameters of the road surface, for example, the consistency of the road surface can be taken into account.

Claims (16)

1. Self-propelled road milling machine (1) for working road surfaces (2),

   - comprising a machine frame (8),

   - comprising a milling drum (12) mounted to rotate and extending in axial direction transverse to the direction of travel (22), and a milling drum housing (10) enclosing the milling drum (12),

   - wherein the milling drum (12) comprises a plurality of tools (16) arranged circumferentially, preferably in the shape of a helix, wherein the tools (16), except for the axial peripheral area, feature a specified mutual line spacing,

   characterized in that
   an oscillation drive (28) exercises an oscillation stroke on the milling drum (12) reciprocating in axial direction relative to the machine frame (8), where the rotating movement of the tools (16) is superimposable with an axial movement parallel to the axis (24) of the milling drum (12), the stroke of which is adjustable to the line spacing between two axially neighbouring tools (16).
2. Road milling machine (1) in accordance with claim 1, characterized in that the amplitude and/or the frequency of oscillation are variably adjustable.
3. Road milling machine (1) in accordance with claim 1 or 2, characterized in that the oscillation stroke is adjustable in the range from 0.5 times to 1.5 times, preferably from 0.9 times to 1.1 times, of the line spacing, or in the range between 3 and 40 mm.
4. Road milling machine (1) in accordance with any one of the claims 1 to 3, characterized in that the frequency of the oscillation is adjustable from 0.1 to 40 Hz.
5. Road milling machine (1) in accordance with any one of the claims 1 to 4, characterized in that the relation of the average axial speed magnitude to the circumferential speed of the milling drum tools is in the range from 0.1 to 3, preferably from 0.25 to 2.
6. Road milling machine (1) in accordance with any one of the claims 1 to 5, characterized in that the milling drum (12) comprises an axial support movable in axial direction.
7. Road milling machine (1) in accordance with any one of the claims 1 to 6, characterized in that a reciprocating movement in the direction of travel (22) is superimposable on the axial support.
8. Road milling machine (1) in accordance with any one of the claims 1 to 3, characterized in that a controller (14) is provided to control or regulate the oscillation frequency and/or the amplitude of the oscillation stroke automatically in accordance with the milling drum rotary speed and/or the advance speed and/or the milling depth of the milling drum (12).
9. Road milling machine (1) in accordance with any one of the claims 1 to 8, characterized in that the milling drum (12) oscillates in axial direction together with the milling drum housing (10), and that the oscillation drive (28) drives the milling drum housing (10) relative to the machine frame (8).
10. Road milling machine (1) in accordance with claim 9, characterized in that the milling drum housing (10) is oscillatable in axial direction along at least two linear guides (42, 44).
11. Road milling machine (1) in accordance with any one of the claims 1 to 8, characterized in that the oscillation drive drives the milling drum (12) in axial direction relative to the milling drum housing (10).
12. Road milling machine (1) in accordance with claim 11, characterized in that the oscillation drive, on the side of the fixed bearing (30), acts axially on a drive shaft of the milling drum (12) extending in the milling drum axis (24).
13. Road milling machine (1) in accordance with any one of the claims 7 to 12, characterized in that the milling drum housing (10) or the milling drum (12) is oscillatable in the direction of travel (22) along at least two linear or arc-shaped guides (46, 48).
14. Method for working road surfaces (2) by means of a road milling machine (1),

    - with a milling drum (12) mounted to rotate at the machine frame (8) and extending axially transverse to the direction of travel (22),

    - with a plurality of tools arranged on the milling drum (12) circumferentially, preferably in the shape of a helix, wherein the tools, except for the axial peripheral area, maintain a specified mutual line spacing,

    characterized in that,
    during operation, an oscillation stroke moving reciprocally in axial direction is exercised on the milling drum (12) in axial direction, wherein the rotating movement of the tools (16) is superimposed with at least one axial movement parallel to the axis (24) of the milling drum (12), the stroke of which is adjusted to the line spacing between two axially neighbouring tools (16).
15. Method in accordance with claim 14, characterized in that an oscillation frequency and/or amplitude of the oscillation is used which is controlled or regulated automatically in accordance with the rotary speed and/or the advance speed and/or the milling depth of the milling drum (12) and/or a parameter of the road surface (2).
16. Method in accordance with claim 14 or 15, characterized in that a high milling drum speed in the range between 180 rpm and 600 rpm is combined with a low oscillation frequency from 0.1 Hz to 5 Hz, or a low milling drum speed in the range from 30 rpm to 180 rpm is combined with a high oscillation frequency from 2 Hz to 40 Hz.

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