EP4036314A1 - Milling head for machining pile heads - Google Patents

Abstract

The milling head (1), which has an axis of rotation (x) and is used to machine a pile head (80) of a pile (8), which comprises a pile core (81), a pile casing (82) and metal reinforcement (83) lying in between , comprises a coupling device (13) which can be connected to a drive shaft (2) of a drive device, a central cutter (11) which has a plurality of central cutters (111) mounted on the underside of an inner ring plate (112), and a ring cutter (12), which has several ring bits (121) mounted on the underside of an outer ring plate (122), which central milling cutter (11) and ring milling cutter (12) are connected to one another, aligned coaxially to the axis of rotation (x), the outer ring plate (122) being connected to one another by a central annular surface (kr2 ) separately encloses the inner ring plate (112). According to the invention, the inner ring plate (112) has at least one transfer opening (1120A, 1120B) leading from the underside to the upper side of the inner ring plate (112), to which on the underside a conveyor blade protruding at least partially into a working area of the central chisel (111). (119A, 119B) and a conveyor spiral (113A, 113B) at the top.

Description

From the WO2008135365A1 a milling head for machining pile heads of piles is known, which comprises a pile core and a pile jacket as well as a metal reinforcement provided between the pile core and the pile jacket.

To be worked concrete piles of this type, which are typically provided in unstable subsoil to support a building object, consist of concrete that can be loaded in compression and rebar that can be loaded in tension. The dimensions of the piles are chosen according to the building object and the building ground and can vary within a wide range. Typically, piles with lengths of 5 m - 50 m and diameters of 0.4 m - 2.5 m are used. For the manufacture of the piles, holes are drilled into the subsoil into which pipes are inserted. The reinforcing iron is inserted into the pipes and the concrete is poured in. Soil material that is located at the lower end of the pipe is usually pushed upwards and is found in the top area after the pile has been completed, which is why it does not have the required strength. Furthermore, the pile or the pile head usually does not have the required dimensions. If necessary, the coupling elements required for the construction project are missing at the pile head. The pile head is therefore usually processed and rebuilt in the required dimensions and quality.

To do this, the prefabricated, usually cylindrical, pile head is machined using a milling head, typically over a length in the range of 0.5 m - 1.5 m, in order to remove the defective concrete. The concrete must be removed in such a way that the rebar, which is typically arranged coaxially to the axis of rotation of the pile, is typically sleeve-shaped, and the intact concrete below the pile head is not damaged. After removing the defective or excess concrete and exposing the rebar, it is usually supplemented with additional rebar and formwork to match the dimensions of the new pile cap to be constructed. The formwork is then filled with concrete and removed after the concrete has hardened.

Traditionally, when processing pile heads, the core of the pile was milled out to the edge of the reinforcement iron. The pile casing was then milled down to the iron reinforcement. This processing usually not only took a lot of time, but also often led to damage to the iron reinforcement. Furthermore, occurred in particular in the Processing of the pile shell caused the previously intact concrete to split, which significantly reduced the available cross-section of the concrete pile, so that the surface pressure transferred from the concrete pile to the built-up object increased accordingly. Corresponding damage to a concrete pile therefore often resulted in considerable consequential damage to an object that was built on defective pile heads. To avoid such consequential damage, defective piles and pile heads therefore had to be repaired at great expense and expense.

When processing pile heads, not only does the time factor play an important role, but also the high-quality finishing of the pile heads, which form a key point in the foundation of a structure, e.g. a building or a bridge.

With the milling head according to the WO2008135365A1 mounted on a construction vehicle such as an excavator, significant advances have been made in terms of processing time of a pile head and processing quality. This milling head comprises a coupling device that can be connected to a drive shaft, a central milling cutter provided with a plurality of central cutters and a ring milling cutter provided with a plurality of ring cutters, which are rigidly coupled to one another and aligned coaxially with the axis of rotation of the drive shaft. This milling head makes it possible to excavate the core of the pile and the mantle at the same time, without damaging the reinforcement of the pile located between the central milling machine and the ring milling machine.

Despite the significant improvement in the processing of pile heads with this milling head, the demand remained to develop a milling head that allows pile heads to be processed even faster and more gently. However, increasing the working speed of a device usually leads to poorer quality work results, which is not permissible in view of the vital importance of the processed objects or the pile heads.

The present invention is therefore based on the object of creating an improved milling head for machining pile heads.

By means of the milling head, pile heads of concrete piles should be able to be processed simultaneously with reduced force, at a higher working speed and with a higher quality of work. The milling head should be able to penetrate more advantageously into the pile head, the pile core and the pile shell, so that concrete material can be removed with less effort and by reducing the effort required, the risk of damage to the processed pile head is reduced at the same time.

When processing the pile heads, the concrete should be treated gently so that accelerated material removal does not result in gaps and cracks in the pile head. At the same time, the load on the milling tools or the chisel should be reduced, so that the maintenance effort for the milling head is reduced accordingly.

The milling head is intended in particular to ensure that the processing of a pile head does not result in any splitting of the pile shell, which, depending on the size, would result in correspondingly high repair costs.

The central drill and milling tools should also be able to be advantageously assembled and disassembled in the desired number, so that there is also less maintenance work in this regard and the milling head can be configured as required with little effort and adapted to the piles to be machined, which can have a diameter of more than 2 m can.

This object is achieved with a milling head which has the features specified in claim 1. Advantageous configurations of the invention are specified in further claims.

The milling head is used to machine a pile head of a pile, typically a concrete pile, which comprises a pile core, a pile casing and a metal reinforcement which lies between the pile core and the pile casing.

The milling head, which is rotated about its longitudinal axis or axis of rotation during operation, comprises a coupling device which can be connected to a drive shaft of a drive device, a central milling machine which has a number of central chisels mounted on the underside of an inner ring plate, and a ring milling machine which has a number of central chisels mounted on the underside of an inner ring plate Underside of an outer ring plate has ring bits mounted, which central milling cutter and ring milling cutter are aligned coaxially to the axis of rotation and are connected to one another, the outer ring plate enclosing the inner ring plate separated from it by a central annular surface.

According to the invention, it is provided that the inner ring plate has at least one transfer opening leading from the underside to the upper side of the inner ring plate, to which an at least partially conveying blade projecting into a working area of the central chisel and adjoining a conveying spiral on the upper side.

With the milling head according to the invention it is possible to remove segments of the pile core and the pile casing simultaneously without damaging the reinforcement of the pile lying in the area of the central annular surface. The processing is carried out with high precision, so that the concrete can be removed even at a short distance of a few centimeters from the reinforcement. The remaining thin concrete sleeve, in which the reinforcement is enclosed, can then be quickly removed using another tool, e.g. pliers.

It is particularly advantageous that the segments of the pile core and the pile casing can be removed by linearly lowering the milling head. Complex movements of a tool, which are difficult to execute and can lead to damage to the pile head, are no longer necessary. The processing of the pile head is therefore possible within a short time without causing any damage.

Due to the linear displacement of the milling head and the correspondingly calculable force effects on the tools, the loads and wear on the milling head are also reduced, which is why maintenance is only necessary at longer intervals.

The at least one conveyor shovel, which protrudes into the working area of the chisel, allows the milled material removed from the concrete core to be grasped and fed through the associated transfer opening to the associated conveyor spiral. By removing the milled material, a major obstacle to work is removed from the working area of the chisel, which is why the milling head can turn with reduced resistance and the central chisel can penetrate the pile core with reduced resistance. On the one hand, the effectiveness of the milling tools increases and, on the other hand, their load is reduced.

By means of the milling head according to the invention, a targeted flow of material is thus implemented, which relieves the milling process and allows efficient removal of the pile core and the pile casing. Due to the targeted flow of material through the at least one transfer opening, the inner ring plate can otherwise be used with a large surface area for the assembly of central chisels. The material flow is therefore not affected by the large mounting surface of the inner ring plate. The desired number of central chisels can therefore be mounted on the underside of the inner ring plate.

The milled material can be removed particularly efficiently if the inner ring plate is provided with two transfer openings, each of which is connected to a conveyor blade at least partially protruding into the working area of the central chisel on the underside and a conveyor spiral on the top. So that the milled material can flow into the conveyor spirals with minimal resistance, it is preferably provided that a connecting surface on the upper side of the inner ring plate connects to each transfer opening, which ensures a laminar or unobstructed transition from the conveyor blade to the associated conveyor spiral.

Preferably, the transfer openings and the conveying blades and the center cutter are diametrically opposed in pairs with respect to the axis of rotation and at equal distances from the axis of rotation. The conveying blades, the central chisel and the ring chisel are preferably also in pairs at the same height. This ensures that the diametrically opposed tools or chisels always act on the pile head in the same way and that disturbing moments or forces caused by asymmetries that could stress the milling head and its guide are avoided. The milling head can therefore be optimally guided and operated with minimal effort. Forces acting laterally on the milling head, which could be unfavorable for the installed tools, such as the chisel and the preferably provided central drill, are avoided.

The inner ring plate is preferably connected to the underside of a shank and the outer ring plate is connected to the underside of a mounting cylinder, the shank and the mounting cylinder being aligned coaxially with the axis of rotation and connected at the top to a coupling plate on which the coupling device is arranged. The mounting cylinder preferably includes at least one exit window through which the conveyed milling material can be discharged, and at least one mounting window which allows manual access to the coupling device, for example.

In a further preferred embodiment it is provided that the at least one conveyor spiral or two conveyor spirals, preferably rotated by 180° relative to one another, is provided with a side wall in a lower section, which is preferably selected according to the height of the pile heads to be processed. The side wall ensures that the milled material in the lower section cannot escape from the spiral conveyors and from the remaining area of the pile head, which contains the Has reinforcement, can be promoted. Only after the milling material has been conveyed out of this area can it emerge laterally in an upper section of the conveying spiral, which is not provided with a side wall, and be guided out of the milling head via the at least one exit window. The side wall of the spiral conveyor thus ensures that the material is transported from the inner ring plate to an area of the spiral conveyor where the milled material is guided away to the side. The side wall can be formed in one piece on the conveyor spiral, which is made of sheet metal, for example, or it can also be welded.

On the underside of the inner ring plate, a central drill is preferably arranged coaxially to the axis of rotation, which protrudes beyond the central chisel and the ring chisel in the milling direction, and is therefore the first to penetrate the pile head or the pile core, thereby performing a guiding function or pilot function and ensuring that the central chisel and ring chisels can follow circular working paths.

In further preferred configurations, it is provided that at least one radial vane is provided on the underside of the inner ring plate, which adjoins the central drill and which is preferably aligned at least approximately radially with respect to the axis of rotation. The at least one radial vane preferably runs from the central drill to the at least one transfer opening. A radial vane is therefore preferably assigned to each transfer opening. The at least one radial blade, which is for example a straight or curved plate, ensures that milled material exposed by the central drill and by radially inner central chisels is guided outwards towards the associated transfer opening. The course of the lower edge or front edge of the radial blade, as well as the course of the lower edge or front edge of the conveying blade, is selected in such a way that contact with the pile core is always avoided. The radial vane is therefore surmounted by the adjacent central chisels in the conveying direction.

According to the invention, the inner ring plate can advantageously fulfill numerous functions. Mounting openings for accommodating the central chisel and/or the radial blades and/or a receiving opening for accommodating an assembly part or drill chuck, which is used to detachably hold the central drill, can be provided on the underside of the inner ring plate. The drill chuck includes, for example, a locking part, by means of which the central drill can be fixed in the drill chuck and, if necessary, released again.

A receiving opening can be provided on the upper side of the inner ring plate for receiving the shaft which connects the inner ring plate to the coupling device.

The assembly part or drill chuck and the shank can be connected to the inner ring plate by known mechanical connection technology, such as by a press fit and/or by a thread. Brackets are preferably provided for the assembly of the central chisel, which are inserted into the assembly openings. The central chisel and the central drill can therefore advantageously be connected to the inner ring plate, which is why maintenance work can be carried out advantageously. In the event of a defect or necessary maintenance, no welding work is necessary. Instead, the center chisel and center drill can be easily detached and replaced.

In further preferred configurations, it is provided that the central chisels are spaced radially from each other at equal or unequal chisel spacings on circular lines or working circles, with the uniform chisel spacing or the different chisel spacings between the working circles preferably being in a range of 20 mm - 40 mm .

During operation or rotation of the milling head about the axis of rotation, the central chisels preferably run in pairs and in pairs diametrically opposite one another in the same working circles that are spaced apart from one another. Due to the radial spacing of the central chisel or the working circles in a range of 20 mm - 40 mm, the material of the pile core is removed particularly efficiently. If the distance is greater than 40 mm, too little material is removed and if the distance is less than 20 mm, the central chisel only penetrates under the action of a significantly increased force, which is preferably avoided in order to prevent damage to the pile head and the milling head. Ideally, the chisel spacing is around 25 mm - 35 mm.

The inner ring plate is preferably offset forwards in the milling direction relative to the outer ring plate, so that the central bits are also offset forwards relative to the ring bits. For example, there is an axial displacement of 10 mm - 25 mm.

Alternatively or additionally, it is preferably provided that the mounting height of the central chisel in the milling direction changes from working group to working group by a height difference that is in a range of 5 mm - 25 mm and increases in the direction of the axis of rotation.

When operating the milling head, the central drill penetrates the core of the pile first. The central chisels then penetrate the pile core sequentially and in stages in pairs, so that the pile core is machined from the inside out. The surface tension of the pile core is broken step by step by arranging the central chisel in a stepped manner. Instead of rupturing the surface of the pile core in one step, the surface tension is broken gradually and thus with reduced force. The milling head according to the invention can therefore be operated efficiently with reduced force or reduced drive torques.

In a further preferred embodiment, the mounting heights of the ring bits are also selected to be different in the milling direction. The assembly height preferably increases in the milling direction from ring chisel to ring chisel or from working group to working group of ring chisels radially outward step by step with a height difference which is preferably in a range of 5 mm - 25 mm.

Since the ring bits on the outermost edge of the outer ring plate have been pushed furthest down in the direction of milling against the pile head, the outermost edge of the pile casing is milled off first. The pile casing is therefore milled from the outside inwards, which avoids spalling. The surface tension of the pile mantle is therefore broken at the outer edge, after which the pile mantle gradually degrades towards the inside.

The central chisel and ring chisel are preferably arranged in at least two spirally running rows and are mounted on the underside of the inner ring plate and the outer ring plate, respectively. The chisel height of the central chisel preferably increases, as described, linearly or non-linearly sequentially from central chisel to central chisel in the direction of the axis of rotation or in the direction of the central drill radially inwards. The chisel height of the ring chisel, on the other hand, preferably increases, as described, linearly or non-linearly sequentially from ring chisel to ring chisel up to the edge of the outer ring plate radially outwards.

The central drill and the central chisels at different installation heights and the ring chisels at different installation heights form in their engagement area or with the corresponding working circles a wave form running concentrically to the axis of rotation, which has a maximum in the area of the axis of rotation in the milling direction, which in the area of the middle annular surface has a minimum and which rises again towards the outer edge of the outer ring plate in the milling direction. The wave shape ensures that the milling head engages optimally in the pile head, which means that it can be processed efficiently but also gently. The surface tensions in the pile core and in the pile shell are advantageously broken, which is why rapid material degradation takes place with reduced energy consumption and at the same time damage such as splitting off of the pile shell is avoided. The invention therefore combines these three essential advantages, which are normally mutually exclusive. With reduced energy consumption, material is broken down faster and more gently. It should be noted that the milling process is promoted on the one hand by the disposal of the milling material according to the invention and on the other hand by the advantageous arrangement of the central chisel and/or ring chisel.

The at least one conveyor blade has a front edge that runs from an inner edge that is closer to the axis of rotation to an outer edge that is further away from the axis of rotation. The conveyor shovel or the conveyor shovels are arranged and aligned in such a way that contact with the pile head is avoided and the loosened milled material is reliably grasped and efficiently transferred to the associated conveyor spiral. The milled material, which is conveyed radially outwards from the inside to the transfer openings by the radial blades, is caught by the conveying blades and conveyed upwards to the conveying spirals. The milled material loosened by the central chisels on the outside, on the other hand, is first picked up from the outside by the conveyor shovels and transferred into a material flow that runs inwards and upwards to the conveyor spirals. This prevents milling material from collecting peripherally on the inner ring plate and impeding the milling process or the rotation of the milling head. So that the material seized by the conveyor shovel is not thrown outwards by centrifugal forces, the conveyor shovels preferably have external shovel walls.

In preferred configurations, at least one clearing tool, e.g. a chisel, is therefore additionally provided, which grasps material on the periphery of the inner ring plate and deflects it inwards. The broaching tool or the broaching chisel preferably protrudes radially outwards beyond the inner ring plate by a broaching width which is preferably in a range of 5 mm to 40 mm.

Preferably, the front edge of the conveying blades is inclined horizontally relative to the diameter of the inner ring plate by a horizontal angle of inclination such that when the milling head rotates in In the working direction, the outer edge of the conveying blade in question is leading and the inner edge is trailing. The horizontal angle of inclination, which is preferably in a range of 5° - 25°, ensures that the milled material is gripped peripherally and guided towards the center of the conveyor bucket.

The front edge of the conveying blades is preferably inclined vertically at a vertical angle of inclination relative to the diameter of the inner ring plate in such a way that the inner edge is preferably higher than the outer edge, corresponding to the course of the mounting height of the central chisel. The vertical angle of inclination is preferably chosen according to the height profile of the central chisel in such a way that between the tips of the central chisel and the front edge of the conveyor blades there is a blade spacing or a distance from the chisel tips and therefore from the surface of the pile core in the range of 5 mm - 40 mm.

The conveyor blades are also inclined by a vertical blade inclination angle relative to the axis of rotation, the front edge of the conveyor blades leading the way during operation of the milling head and the vertical blade inclination angle preferably being in a range between 5° and 85°.

The at least one radial vane and/or the at least one conveying vane are preferably held at least partially in a form-fitting manner in a recess or assembly opening provided in the inner ring plate. In this way, the radial blades and the conveyor blades can be assembled and disassembled easily. The at least one radial vane and/or the at least one conveying vane can, however, also be fully or partially welded to the inner ring plate, it preferably being provided that the radial vane and the conveying vane bear at least partially flat against a support surface of the inner ring plate.

The central chisels provided on the central milling machine and the ring chisels provided on the ring milling machine preferably consist of a holder that can be welded or mounted in a form-fitting manner and a chiseling element that can be inserted therein and that can be routinely replaced. The holders are preferably connected to the associated holders or assembly elements of the ring plates by means of form-fitting connections, for example dovetail connections. The ring chisels are preferably dimensioned somewhat larger than the central chisels. Further one of the ring bits can be connected to the inner ring plate as a clearing bit.

The inside and outside diameters of the inner ring plate and the outer ring plate are preferably precisely adapted to the dimensions of the pile and the position of the reinforcement in the pile, so that maximum removal of concrete is ensured without damaging the reinforcement. The milling head is therefore provided according to the dimensions of the pile head to be processed, which can have an outside diameter of over 2 m.

Central milling and ring milling can preferably be combined with one another in any dimensions or connected to one another by the coupling plate. Furthermore, outer ring plates with different dimensions and/or differently equipped with tools can be releasably connected to the assembly cylinder. Furthermore, preferably differently dimensioned inner ring plates and/or differently equipped with tools can be releasably connected to the shank. In this way, the milling head can be flexibly adapted to the pile heads to be processed.

The milling head is made of durable material, especially iron and steel. The tool parts that come into contact with the concrete pile are preferably made of hard metal. Typically, the milling tools include receiving openings are used in the hard metal elements that are used to machine the concrete. Plastic parts can be used if they have the desired strength and should give the milling head or parts of it a certain elasticity, for example.

Fig. 1a

in Schnittdarstellung einen erfindungsgemässen Fräskopf 1 zur Bearbeitung von Pfahlköpfen 80 mit einer Kopplungsvorrichtung 13, mit einer Ringfräse 12, die mehrere an der Unterseite einer Aussenringplatte 122 montierte Ringmeissel 12 aufweist, und mit einer Zentralfräse 11, die eine Innenringplatte 112 aufweist, an deren Unterseite 112 mehrere Zentralmeissel 111 vorgesehen sowie zwei Förderschaufeln 119A, 119B angrenzend an Transferöffnungen 1120A, 1120B montiert sind, durch die hindurch gelöstes Fräsmaterial aus dem Arbeitsbereich der Zentralmeissel 111 zu Förderspiralen 113A, 113B förderbar ist;

Fig. 1b

den Fräskopf 1 von Fig. 1a während der Bearbeitung eines Pfahlkopfs 80, dessen Pfahlkern 81 und Pfahlmantel 82, zwischen denen die unbeschädigte Eisenarmierung 83 in einer relativ dünnen Betonhülse 88 gehalten ist, bereits in der Höhe h2 abgetragen wurden;

Fig. 2

den Fräskopf 1 von Fig. 1a von unten mit Blick auf die mit den Zentralmeisseln 111 bestückte Innenringplatte 112 und die mit den Ringmeisseln 121 bestückte Aussenringplatte 122, die entsprechend der Geometrie des bearbeiteten Pfahls 8 eine dem Pfahlkern 81 entsprechende zentrale Kreisringfläche kr1 und eine dem Pfahlmantel 82 entsprechende äussere Kreisringfläche kr3 abdecken und eine mittlere Kreisringfläche kr2 begrenzen, in welche eine nach der Bearbeitung des Pfahlkopfs 80 verbliebene Betonhülse 88 mit der Eisenarmierung 83 eintreten kann;

Fig. 3a

die Innenringplatte 112 von Fig. 2, die mit zwei Serien 111A, 111B von spiralförmig angeordneten Zentralmeisseln 111, einem Zentralbohrer 114 bestückt und mit zwei Transferöffnungen 1120A, 1120B versehen ist, an die seitlich je eine Radialschaufel 118A, 118B und in Drehrichtung rückseitig je eine Förderschaufel 119A, 119B angrenzen und an deren Frontseite je ein Räumungsmeissel 1119A, 1119B vorgesehen ist;

Fig. 3b

die Innenringplatte 112 von Fig. 3a mit eingezeichneten Arbeitskreisen ml der beiden Serien 111A, 111B von Zentralmeisseln 111, von denen je zwei, die einander bezüglich der Drehachse x des Fräskopfs 1 bzw. des Zentralbohrers 114 diametral gegenüber liegen, entlang einem gemeinsamen Arbeitskreis ml geführt werden;

Fig. 4

einen Teil der Zentralfräse 11 mit der Innenringplatte 112, dem Zentralbohrer 114, nur drei montierten Zentralmeisseln 1112A, 1115B, 1118A und einer der Transferöffnungen 1120B, an die die zugehörige Radialschaufel 118B und die zugehörige Förderschaufel 119B, die in den Arbeitsbereich der Zentralmeissel 111 hineinragen, angrenzen;

Fig. 5a

die vollständig mit Zentralmeisseln 111, Radialschaufeln 118A, 118B, Förderschaufeln 119A, 119B, Räumungswerkzeugen 1119A, 1119B und dem Zentralbohrer 114 bestückte Innenringplatte 112 von Fig. 3a in räumlicher Darstellung;

Fig. 5b

die Innenringplatte 112 von Fig. 5a nach Entfernung der Zentralmeissel 111 und der Förderschaufel 119B sowie der Entnahme des Zentralbohrers 114 mitsamt Bohrfutter 1143 aus einer Ausnehmung 1129 der Innenringplatte 112;

Fig. 6a

die Innenringplatte 112 von Fig. 5a von oben mit den an die Oberseite der Innenringplatte 112 anschliessenden Förderspiralen 113A, 113B, die um 180° gegeneinander gedreht den Schaft 115 der Zentralfräse 11 umlaufen und die in diesem Abschnitt je mit einer Spiralwand 1130 versehen sind, sowie in Frontansicht die Transferöffnung 1120B, an die an der Unterseite die in den Arbeitsbereich der Zentralmeissel 111 hinein ragende Förderschaufel 119B und an die an der Oberseite die Förderspirale 113B anschliesst;

Fig. 6b

die Innenringplatte 112 von Fig. 6a mit den Transferöffnungen 1120A, 1120B und ohne die Förderspiralen 113A, 113B, den Schaft 115 und die Förderschaufel 119B;

Fig. 7a

einen Zentralmeissel 111, der eine Halterung 111F und ein darin eingesetztes Meisselelement 111M umfasst; und

Fig. 7b

einen Ringmeissel 121, der eine Halterung 121F und ein darin eingesetztes Meisselelement 121M umfasst.

The invention is explained in more detail below with reference to drawings. It shows:

Fig. 1a

a sectional view of a milling head 1 according to the invention for machining pile heads 80 with a coupling device 13, with a ring milling machine 12, which has a plurality of ring bits 12 mounted on the underside of an outer ring plate 122, and with a central milling machine 11, which has an inner ring plate 112, on its underside 112 a plurality of center cutters 111 are provided and two conveying blades 119A, 119B are mounted adjacent transfer openings 1120A, 1120B through which loosened material is passed Milling material can be conveyed from the working area of the central chisel 111 to the spiral conveyors 113A, 113B;

Fig. 1b

the milling head 1 from Fig. 1a during the processing of a pile head 80, the pile core 81 and pile shell 82, between which the undamaged iron reinforcement 83 is held in a relatively thin concrete sleeve 88, have already been removed at the height h2;

2

the milling head 1 from Fig. 1a from below with a view of the inner ring plate 112 fitted with the central chisels 111 and the outer ring plate 122 fitted with the ring chisels 121, which cover a central circular ring surface kr1 corresponding to the pile core 81 and an outer circular ring surface kr3 corresponding to the pile casing 82 in accordance with the geometry of the machined pile 8 and delimit a central annular surface kr2, into which a concrete sleeve 88 with the iron reinforcement 83 remaining after the machining of the pile head 80 can enter;

Figure 3a

the inner ring plate 112 of 2 , which is equipped with two series 111A, 111B of spirally arranged central chisels 111, a central drill 114 and is provided with two transfer openings 1120A, 1120B, on each side of which a radial blade 118A, 118B and, in the direction of rotation, a conveying blade 119A, 119B on the back a clearing chisel 1119A, 1119B is provided on the front side;

Figure 3b

the inner ring plate 112 of Figure 3a with marked working circles m1 of the two series 111A, 111B of central chisels 111, of which two each, which are diametrically opposite one another with respect to the axis of rotation x of the milling head 1 or the central drill 114, are guided along a common working circle m1;

4

a part of the central milling machine 11 with the inner ring plate 112, the central drill 114, only three mounted central chisels 1112A, 1115B, 1118A and one of the transfer openings 1120B, adjoined by the associated radial blade 118B and the associated conveying blade 119B, which protrude into the working area of the central chisel 111;

Figure 5a

the inner ring plate 112 of FIG Figure 3a in spatial representation;

Figure 5b

the inner ring plate 112 of Figure 5a after removing the central chisel 111 and the conveying blade 119B and removing the central drill 114 together with the drill chuck 1143 from a recess 1129 in the inner ring plate 112;

Figure 6a

the inner ring plate 112 of Figure 5a from above with the conveyor spirals 113A, 113B adjoining the upper side of the inner ring plate 112, which encircle the shaft 115 of the central milling cutter 11 rotated by 180° in relation to one another and which are each provided with a spiral wall 1130 in this section, as well as a front view of the transfer opening 1120B the conveyor blade 119B protruding into the working area of the central chisel 111 on the underside and the conveyor spiral 113B on the upper side;

Figure 6b

the inner ring plate 112 of Figure 6a with transfer ports 1120A, 1120B and without conveyor spirals 113A, 113B, shaft 115 and conveyor blade 119B;

Figure 7a

a center chisel 111 comprising a mount 111F and a chisel element 111M inserted therein; and

Figure 7b

a ring bit 121 comprising a holder 121F and a bit element 121M inserted therein.

Fig. 1a shows a sectional view of a milling head 1 according to the invention, which, as Fig. 1b shows, is provided for processing pile heads 80 of concrete piles 8.

The milling head 1 comprises a central milling cutter 11 and a ring milling cutter 12 which are connected to one another and to a coupling device 13 on the upper side by a coupling plate 133 and a counter plate 134 . The coupling device 13 comprises a coupling sleeve 131 into which a drive shaft 2 of a drive device (not shown) can be inserted and locked, for example by means of a bolt 132 . The drive shaft 2 is held, for example, by a construction vehicle that is able to rotate the drive shaft 2 about an axis of rotation x or about the longitudinal axis of the milling head 1 and to move it axially. The milling head 1 can therefore be lowered in rotation coaxially onto a pile head 80 in order to machine it, like this Fig. 1b indicates. In all of the exemplary embodiments, the milling head 1 is rotated clockwise for this purpose, as seen from above.

The ring milling machine 12 comprises an outer ring plate 122, on the underside of which ring bits 121 are mounted in the direction of rotation or inclined thereto. The upper side of the outer ring plate 122 is preferably detachably connected to the underside of a mounting cylinder 123, e.g. by means of flange elements and screws or threaded elements, the upper side of which is preferably detachably connected to the coupling plate 133, e.g. by means of flange elements and screws or threaded elements. The assembly cylinder 123 has a quarter section through which the view of the central milling machine 11 is uncovered. On the underside, the assembly cylinder 123 has exit windows 1231 through which loosened milling material can be carried away to the outside. The assembly cylinder 123 has assembly windows 1232 on the upper side, which allow access to the milling head 1, e.g. in order to release the central milling machine 11.

The central milling machine 11 comprises an inner ring plate 112, on the underside of which central chisels 111 are mounted aligned in the direction of rotation or at an angle thereto. Aligned coaxially to the axis of rotation x, a central drill 114 is provided on the underside of the inner ring plate 112, which protrudes beyond the central chisel 111 and the annular chisel 121 in the milling direction. The inner ring plate 112 also has two transfer openings 1020A, 1020B (see FIG Figure 3a ), which are diametrically opposite each other with respect to the axis of rotation x, and which are each assigned a radial blade 118A, 118B and a conveyor blade 119A, 119B.

A conveyor spiral 113A, 113B connects to the transfer openings 1020A, 1020B at the top. The conveyor spirals 113A, 113B, which after enclosing a shaft 115 at the top are preferably formed from solid sheet metal. The underside of the shaft 115 is connected to the inner ring plate 112 and is preferably releasably held by a connecting device 14 on the upper side. The shaft 115 is connected to the coupling device 13 in a non-positive and/or positive manner by means of the connecting device 14 . The connecting device 14 preferably comprises clamping devices which are distributed along the circumference of the shaft 115 and which allow the shaft 115 to be clamped to the counter plate 134 . The connecting device 14 thus allows the shank 115 and thus the central milling cutter 11 to be detached from the milling head 1 . The central milling machine 11 can therefore be detached, serviced and reused, or replaced by a central milling machine 11 which has different properties.

Fig. 1b shows the milling head 1 from Fig. 1a during the processing of a sectioned pile head 80 of a pile 8, which has a height h1 and a diameter d. The pile core 81 and the pile shell 82, between which the undamaged iron reinforcement 83 is held in a relatively thin concrete sleeve 88, have already been removed over a height difference h2 from top to bottom. The loosened milled material was picked up by the conveyor blades 119A, 119B and fed through the transfer openings 1220A, 1220B to the conveyor spirals 113A, 113B and lifted by them over the pile head 80 or the remaining concrete sleeve 88 and carried away. Within the pile head 80, the milled material is held laterally by a spiral wall 1130 which is peripherally formed or welded to the conveying spirals 113A, 113B. The milled material is therefore lifted over the pile head 80 and only then discharged outwards to the outlet openings 1231 of the assembly cylinder 123 under the action of centrifugal force.

Fig. 1b also shows that the central chisel 111 and the ring chisel 121 are at different heights and thus engage in the pile head 80 at different depths. At least the central chisels 111 close to the central drill 114 are all lower in the milling direction than the ring chisels 121. The central chisels 111 and ring chisels 121 are also mounted at different heights in the milling direction on the inner ring plate 112 and the outer ring plate 122. The mounting height of the central chisel 111 increases radially in the direction of the axis of rotation x, preferably from central chisel 111 to central chisel 111 in steps. The mounting height of the ring chisel 121 increases radially outwards, preferably from ring chisel 121 to ring chisel 121 in steps. A linear or non-linear increase can be provided. The central drill 114 itself, which takes on a guiding function or pilot function, protrudes beyond the central chisel 111 at the bottom.

Fig. 1b shows a cross-section through the pile head 8 with the symmetrical course of the milling line dl, which, according to the arrangement of the central drill 114, the central chisel 111 and the ring chisel 121, reaches a maximum in the area of the axis of rotation and in the area of the concrete sleeve 88 or in the area of the middle annular surface kr2 is interrupted and has a minimum and then rises again outwards in the milling direction. When the pile head 8 is machined, a corresponding wave form running concentrically to the axis of rotation x therefore results on its surface. This waveform ensures that the central milling cutter 11 and the ring milling cutters 12 optimally engage in the pile head 80 and break up the pile core 81 from the inside out and the pile shell 82 from the outside in. This gradual processing of the pile head 80 allows the surface tension in the pile core 81 and the surface tension in the pile mantle 82 to be advantageously resolved without damage to the pile head 80 occurring.

After the processing of the pile head 80 has been completed, the milling head 1 is raised again. The remaining concrete sleeve 88, which still encloses and protects the iron reinforcement 83, is then removed with little effort using other tools, such as milling machines and clamps.

2 shows the milling head 1 from below with a view of the inner ring plate 112 fitted with the central chisels 111 and the outer ring plate 122 fitted with the ring chisels 121, which, depending on the geometry of the machined pile 8, has a central annular surface kr1 corresponding to the pile core 81 and an outer one corresponding to the pile jacket 82 Cover circular ring area kr3 and delimit a central circular ring area kr2, into which a concrete sleeve 88 with iron reinforcement 83 remaining after machining of pile head 80 can enter. A part of the central annular area kr2 is shown hatched.

The outer ring plate 122 has an outside diameter d122o and an inside diameter d122i. The inner ring plate 112 has an outer diameter d112.

On the outer ring plate 122 are three series 121A, 121B, 121C of twelve ring bits 121 or 1211, 1212, . . . Three ring chisels 121 each follow the same working circle m1 (only one working circle m1 shown). The mounting height of the ring chisel 121 increases from the first ring chisel 1211 to the last ring chisel 12112 or from one working circle ml to the next working circle ml radially from the inside to the outside, preferably steadily, which is why the outermost ring chisels 12112 are highest in the milling direction and therefore first the outer edge of the Detect pile mantle 82. In this way, the pile casing 82 is processed from the outside in, which is why damaging spalling is avoided. The increase in the mounting height of the ring bit 121 is preferably in a range of 5 mm - 25 mm. For example, the increase in mounting height of the first ring bits 1211, 1212, ... is close to 5 mm and the increase in mounting height of the last ring bits ..., 12111, 12112 is close to 25 mm.

On the inner ring plate 112, which is in Figure 3a is shown larger, two series 111A, 111B of eight spirally arranged central chisels 111 or 1111, 1112, ..., 1118 are each offset by 180°.

As Figure 3b shows, two diametrically opposite central chisels 111 each follow the same working circle ml. The mounting height of the central chisel 111 preferably increases steadily radially from the outside in from the first central chisel 1111 to the last central chisel 1108, which is why the central chisel 1108 closest to the axis of rotation x are highest in the milling direction and therefore penetrate first into the center of the pile core 81 after the central drill 114. In this way, the pile core 81 is processed from the inside out, whereby the processing of the pile core 81 can be carried out more quickly.

For example, the increase in mounting height of the first ring bits 1111, 1112, ... is close to 5 mm and the increase in mounting height of the last ring bits ..., 1107, 1108 is close to 25 mm.

The central chisels 111 are offset radially in pairs at equal or unequal chisel spacings ma and each define a working circle ml during rotation. The difference in the radii of the working circles ml corresponds to the respective chisel spacing. The uniform Chisel distance ma or the different chisel distances ma are preferably in a range of 20 mm - 40 mm. With this arrangement of the central chisel, the material is optimally removed. The working circles ml are thus offset radially and also in height from one another

The inner ring plate 112 also has two diametrically opposite transfer openings 1120A, 1120B with respect to the axis of rotation x, through which the loosened milling material can be removed. To transport the milling material away, a conveyor blade 119A, 119B is provided adjacent to the trailing edge of each of the transfer openings 1120A, 1120B, which on the one hand partially extends into the area of the respective transfer opening 1120A, 1120B and on the other hand partially into the working area of the central chisel 111. At the front, the conveyor blades 119A, 119B have a front edge 1193, which runs from an inner edge to an outer edge of the conveyor blades 119A, 119B. The conveying blades 119A, 119B therefore engage with the front edge 1193 first in the exposed milled material in order to carry it away upwards via the conveying blades 119A, 119B.

Figure 3a shows that the front edge 1193 is inclined horizontally relative to the diameter d112 of the inner ring plate 112 by a horizontal angle of inclination a1 such that when the milling head 1 rotates in the working direction, the outer edge 1192 of the relevant conveyor blade 119A; 119B leads and the inner edge 1191 lags. The milled material is therefore first caught on the outside of the front edge 1193 and pushed inwards towards the associated transfer opening 1120A, 1120B. The shifting of the milled material results in an advantageous material flow, which relieves the conveyor blades 119A, 119B. The horizontal tilt angle or lead angle a1 is preferably in a range of 0° - 25°.

In addition, each of the transfer openings 1120A, 1120B is assigned a radial blade 118A, 118B, which conveys the milling material exposed by the central drill 114 and the internal central chisels 111 to the outside to the transfer openings 1120A, 1120B. The radial vanes 118A, 118B may be simple plates which are preferably positively retained by the inner ring plate 112 and are preferably radially or inclinedly aligned with the associated transfer port 1120A, 1120B.

Figure 3b 1120A, 1120B also shows that a clearing chisel 1119A, 1119B is mounted on the leading edge of the transfer openings 1120A, 1120B and protrudes outwards from the inner ring plate 112 by a clearing width b, which is preferably in a range of 5 mm-40 mm. The clearing chisels 1119A, 1119B grasp not yet loosened concrete parts, which could damage the conveying shovels 119A, 119B, as well as the milling material lying on the outside and convey it radially inward so that it can be grasped by the conveying shovels 119A, 119B. The clearing chisels 1119A, 1119B are preferably identical to the annular chisels 121, which are preferably dimensioned larger than the central chisels 111.

So that the milled material can be grasped well at the periphery, the conveying blades 119A, 119B can also protrude radially outwards from the inner ring plate 112 by up to 35 mm.

Figure 3b FIG. 1 also shows that the inner ring plate 112 has assembly openings 1128 on the underside, into which the central chisel 111 or holders for the central chisel 111 are inserted.

4 shows part of the central milling machine 11 with the inner ring plate 112, the central drill 114, only three mounted central chisels 1112A, 1115B, 1118A and one of the transfer openings 1120B, to which the associated radial blade 118B and the associated conveying blade 119B, which protrude into the working area of the central chisel 111 , adjoin. The depth of penetration is shown for each of these tools; for the central drill 114 the penetration depth t0, for the central bits 1112A, 1115B, 1118A the penetration depths t1, t2, t3, for the inner edge 1181 and the outer edge 1182 of the radial blade 118B the penetration depths t1181, t1182 and for the inner edge 1191 and the outer edge 1192 of the Conveyor blade 119B the penetration depths t1191, 1192.

The front edge 1183 of the radial vane 118B runs from the inner edge 1181 to the outer edge 1182 or from the penetration depth t1181 to the penetration depth t1182 with a falling inclination outwards. The front edge 1193 of the conveying blade 119B runs from the inner edge 1191 to the outer edge 1192 or from the penetration depth t1191 to the penetration depth t1182 with a falling inclination outwards.

The front edge 1193 of the conveyor blade 119B is vertically inclined relative to the diameter d112 of the inner ring plate 112, preferably by a vertical angle of inclination a2, in such a way that the inner edge 1191 is preferably higher in the conveying direction than the outer edge 1192, corresponding to the course of the mounting heights of the central chisel 111. The conveyor blade 119B can therefore not come into contact with the surface of the pile head 80 or the pile core 81.

A blade distance a3 is preferably provided between the front edge 1193 of the conveyor blade 119 and the working circles m1 of the central chisel 111 or the tips of the central chisel 111, which is in a range of preferably 5 mm-40 mm.

4 shows further that the central drill 114, which comprises a milling tool or drilling tool 1141 and a tool shank 1142, is held in a mounting part or drill chuck 1143 and fixed by means of a locking part 11431, for example by a bolt.

Figure 5a shows the complete with central chisels 111; radial vanes 118A, 118B; conveyor blades 119A, 119B; clearing tools 1119A, 1119B; and the central drill 114 tipped inner ring plate 112 of Figure 3a in spatial representation. A series of central chisels 111 is provided with the associated serial numbers 1111, 1112, ..., 1108. Also shown on the right is a view over impeller blade 119B through transfer opening 1120B.

Figure 5b shows the inner ring plate 112 of FIG Figure 5a after removal of the central chisel 111 and the conveying blade 119B as well as the removal of the central drill 114 together with the drill chuck 1143 from a recess 1129 in the inner ring plate 112. Also visible are recesses 1123 on the underside of the inner ring plate 112, which serve to accommodate the radial blades 118A, 118B. The housing 121F of the reaming chisel 1119B also remained.

In order to achieve the assembly heights or for mutual vertical displacement of the central chisel 111, the underside of the inner ring plate 112 is provided with annular steps S1, S2, S3, S4, S5, which preferably correspond to the working groups m1.

Figure 6a shows the inner ring plate 112 of FIG Figure 5a from above with the conveyor spirals 113A, 113B adjoining the upper side of the inner ring plate 112 and set against one another by 180°, which encircle the shaft 115 of the central milling cutter 11 and which are each provided with a spiral wall 1130 in this section. The transfer opening 1120B, to which the conveyor blade 119B, which projects into the working area of the central chisel 111, is connected on the underside and the conveyor spiral 113B on the top. The inner ring plate 112 has a transfer surface 1125A, 1125B for each of the transfer openings 1020A, 1020B, via which the milled material is conveyed from the conveying blade 119A, 119B to the associated conveying spiral 113A, 113B. It is possible to completely cover this transfer surface 1125A, 1125B by the conveying blade 119A, 119B. The conveyor blade 119A, 119B can therefore be welded to the lower end of the transfer surface 1125A, 1125B at the front, for example, or it can also be attached to the associated transfer surface 1125A, 1125B, if necessary screwed on.

The conveyor blade 119B, which connects to the underside of the transfer opening 1120B or runs further, is inclined by a blade inclination angle a4 with respect to the axis of rotation x and forms an inclined plane. The blade inclination angle α4 at which the conveying blade 119B is inclined with the front edge 1193 forward under the transfer opening 1120B is in a range of preferably 5° - 85°. A vertical orientation of the conveyor blade 119B is preferably avoided, in which case the milled material is pushed forward and is hardly displaced upwards. The blade inclination angle a4, which is approximately 45° in the embodiment shown, is therefore selected in such a way that the milled material can reach the transfer opening 1020B via the conveyor blade 119B and on to the conveyor spiral 113B. The conveying blade 119B has an outer wall 119S so that the conveyed milling material cannot escape to the outside.

The transfer surface 1125B is preferably shaped in such a way that a preferably laminar transition without obstacles results between the conveyor blade 119B at the entrance of the conveyor spiral 113B.

Figure 6b shows the inner ring plate 112 of FIG Figure 6a without the feed spirals 113A, 113B, the shaft 115 and the feed blade 119B. After removal of the conveyor blade 119B, a connection space with a connection surface 1127 is exposed at the lower edge of the transfer surface 1125B or on the underside of the transfer opening 1120B, in which the conveyor blade 119B is fastened. eg screwed and/or welded. Likewise, the connection surfaces 1126A, 1126B of the spiral conveyors 113A, 113B are exposed, which run up to an edge or a stop 11261, which is flush with the upper edge of the associated spiral conveyor 113A, 113B, so that the milled material can enter the spiral conveyor 113A, 113B unhindered.

Figure 7a shows a central chisel 111, which comprises a holder 111F and a chisel element 111M inserted therein.

Figure 7b 12 shows a ring bit 121 comprising a holder 121F and a bit element 121M inserted therein. Ring bit 121 is also used as a reaming bit in the present embodiment, like this Figure 6b indicates.

Reference List

1

milling head

11

central milling machine

111, 1111, ..., 1118

central chisel

111A, 111B

central pick groups

111F

chisel holder

111M

chisel or tool

1119A, 1119B

Clearing tool, clearing chisel

112

inner ring plate

1120A, 1120B

transfer ports

1123

Mounting holes for the radial vanes

1124

Receiving opening for the shaft 115

1125A, 1125B

Transfer surfaces of the transfer openings

1126A, 1126B

Connection surface for the conveyor spirals

1127

Connection surfaces for the conveyor blades

1128

Mounting openings for central chisel 111

1129

Opening for mounting part 1143

113A, 113B

conveyor spirals

1130

spiral wall

114

central drill

1141

Milling tool, carbide cutting edges

1142

tool shank

1143

Mounting part, drill chuck

11431

locking part

115

shaft

118A, 118B

radial vanes

1181

Inner edge of the radial vanes

1182

Outer edge of the radial vanes

1183

Front edge of the radial vanes

119A, 119B

conveyor shovel

1191

Inner edge of the conveyor vanes

1192

outer edge of the conveyor vanes

1193

Front edge of the conveyor blades

1195

outer wall of the conveyor vanes

12

ring cutter

121; 1211, ..., 12112

ring chisel

121A, ..., 121C

ring bit groups

121F

chisel holder

121M

chisel or tool

122

outer ring plate

123

mounting cylinder

1231

exit window

1232

Mounting window for access

13

coupling device

131

coupling sleeve

132

Coupling means, coupling bolts

133

coupling plate

134

counter plate

14

connecting device

2

drive shaft

8th

stake

81

pile core

82

pile coat

83

metal reinforcement

88

concrete sleeve

a1

horizontal slope angle of the front edge

a2

vertical angle of inclination of the front edge

a3

blade clearance

a4

blade inclination angle

b

clearing width

i.e

pile diameter

d112

Outer diameter inner ring plate

d122i

Inner diameter outer ring plate

d122o

Outer diameter outer ring plate

dl

Milling line along the pole diameter

h1

pile height

h2

pile head height

kr1,

central circular area

kr2

mean circular area

kr3

outer circular surface

mom

tool spacing

ml

Chisel lines, working groups

S1, ..., S5

Steps on the inner ring plate 112

t0

Penetration depth of the central drill

t1

Penetration depth of the center chisel 1118A

t2

Penetration depth of the center chisel 1115B

t3

Penetration depth of the center chisel 1112A

t1181

Penetration depth inside edge of radial vane

t1182

Penetration depth outer edge radial vane

t1191

Penetration depth inside edge of conveyor shovel

t1192

Penetration depth of the outer edge of the conveyor blade

Claims (15)

Milling head (1) with an axis of rotation (x) for machining a pile head (80) of a pile (8), which comprises a pile core (81), a pile casing (82) and metal reinforcement (83) lying in between, with a coupling device (13 ), which can be connected to a drive shaft (2) of a drive device, with a central milling cutter (11), which has a plurality of central chisels (111) mounted on the underside of an inner ring plate (112), and with a ring milling cutter (12), which has a plurality of central chisels (111) on one has ring bits (121) mounted on the underside of an outer ring plate (122), which central milling cutter (11) and ring milling cutter (12) are connected to one another, aligned coaxially to the axis of rotation (x), with the outer ring plate (122) being separated from it by a central annular surface (kr2). Enclosing the inner ring plate (112), characterized in that the inner ring plate (112) has at least one transfer opening (1120A, 1120B) leading from the bottom to the top of the inner ring plate (112) to which on the underside a conveyor blade (119A, 119B) which projects at least partially into a working area of the central chisel (111) and which is adjoined on the upper side by a conveyor spiral (113A, 113B). Milling head (1) according to Claim 1, characterized in that the inner ring plate (112) has two transfer openings (1120A, 1120B), to each of which a conveying blade (119A; 119B ) and to which a conveyor spiral (113A; 113B) is connected at the top. Milling head (1) according to Claim 1 or 2, characterized in that the transfer orifices (1120A, 1120B) and the conveying blades (119A, 119B) and the central cutters (111) are diametrically opposed in pairs with respect to the axis of rotation (x) and are equidistant from the axis of rotation (x) opposite. Milling head (1) according to Claim 1, 2 or 3, characterized in that the inner ring plate (112) is connected to the underside of a shank (115) and that the outer ring plate (122) is connected to the underside of a mounting cylinder (123), and that the shaft (115) and the mounting cylinder (123) are aligned coaxially to the axis of rotation (x) and are connected at the upper side to a coupling plate (133) on which the coupling device (13) is arranged. Milling head (1) according to one of Claims 1 - 4, characterized in that the at least one conveyor spiral (113A; 113B) or two conveyor spirals (113A; 113B) preferably rotated by 180° in relation to one another in a lower section which preferably corresponds to the height of the pile heads (80) to be processed is selected, is provided with a side wall (1130). Milling head (1) according to one of Claims 1 - 5, characterized in that on the underside of the inner ring plate (112) there is arranged a central drill (114) which is aligned coaxially to the axis of rotation (x) and which contains the central chisel (111) and the ring chisel (121 ) protrudes in the milling direction, and that at least one radial blade (118A, 118B) adjoining the central drill (114) is provided on the underside of the inner ring plate (112), which is preferably aligned radially with respect to the axis of rotation (x). Milling head (1) according to one of Claims 1 - 6, characterized in that the central drill (114) is detachably held in a mounting part or drill chuck which is inserted into a receiving opening (1129) on the underside of the inner ring plate (112). Milling head (1) according to one of Claims 1 - 7, characterized in that the central chisels (111) are each offset radially from one another at equal or unequal chisel spacings (ma) and define working circles (ml) during rotation, the uniform chisel spacing (ma ) or the different chisel distances (ma) or the radial distances of the working circles (ml) of the central chisel (111) are preferably in a range of 20 mm - 40 mm. Milling head (1) according to one of Claims 1 - 8, characterized in that the central chisels (111) are spaced radially from one another at equal or unequal chisel spacings (ma) on working circles (ml), the mounting height of the central chisels (111) being in the milling direction from one working circle (ml) to the next working circle (ml) by a height difference which preferably lies in a range of 5 mm - 25 mm, and increases in the direction of the axis of rotation (x). Milling head (1) according to one of Claims 1 - 9, characterized in that the ring bits (121) are radially offset from one another at equal or unequal bit spacings and define working circles (ml) during rotation, the mounting height of the ring bits (121) being from one working circle (ml) to the next working circle (ml) in the milling direction radially outwards by one Height difference, which is preferably in a range of 5 mm - 25 mm increases. Milling head (1) according to one of Claims 1 - 10, characterized in that the central drill (114) and the central chisel (111) and ring chisel (121) lying at different mounting heights have a concentric to the axis of rotation in their engagement area or with their working circles (ml). (x) forming a wave shape which has a maximum in the area of the axis of rotation (x) in the milling direction, which has a minimum in the area of the central annular surface (kr2) and which rises again towards the outer edge of the outer ring plate (122) in the milling direction. Milling head (1) according to one of Claims 1 - 11, characterized in that the at least one conveyor blade (119A, 119B) has a front edge (1193) which extends from an inner edge (1191) closer to the axis of rotation (x) to one of the axis of rotation (x) that lies further away from the outer edge (1192), which front edge (1193) is inclined horizontally relative to the diameter (d112) of the inner ring plate (112) by a horizontal angle of inclination (a1) such that when the milling head (1) rotates in working direction, the outer edge (1192) leads and the inner edge (1191) lags behind. Milling head (1) according to one of Claims 1 - 12, characterized in that the at least one conveyor blade (119A, 119B) has a front edge (1193) which extends from an inner edge (1191) closer to the axis of rotation (x) to one of the The axis of rotation (x) runs further away from the outer edge (1192), which front edge (1193) is inclined vertically by a vertical angle of inclination (a2) relative to the diameter (d112) of the inner ring plate (112) in such a way that the inner edge (1191) preferably corresponds to the course the mounting height of the central chisel (111) is higher than the outer edge (1192). Milling head (1) according to one of Claims 1 - 13, characterized in that the at least one conveyor blade (119A, 119B) has a front edge (1193) which extends from an inner edge (1191) closer to the axis of rotation (x) to one of the Axis of rotation (x) that lies further away from the outer edge (1192), which front edge (1193) is set back over the entire length by a blade spacing (a3) in the range of preferably 5 mm - 40 mm in the milling direction in relation to the working circles (m1) of the central chisel (111). lies. Milling head (1) according to one of Claims 1 - 14, characterized in that the at least one conveyor blade (119A, 119B) is inclined by a vertical blade inclination angle (a4) relative to the axis of rotation (x), the front edge (1193) of the conveyor blade ( 119A, 119B) and the blade inclination angle (a4) is in a range of preferably 5° - 85°.

Images