Slot wall milling machine and method for creating a milling slot in the ground

Description

[0001] The invention relates to a diaphragm wall cutter with a box-shaped housing, on the top of which a lifting device can be attached, at least one milling wheel which is arranged on a bottom of the housing and can be driven to remove soil material by rotation, wherein milling teeth are arranged along the outer circumference of the milling wheel in at least one circumferential row, to which at least one axial clearance is adjacent, and at least one clearing plate which is arranged relatively stationary to the housing and into which the at least one circumferential clearance on the milling wheel engages for clearing soil material, according to the preamble of claim 1.

[0002] The invention further relates to a method for creating a milling slot in the ground according to the preamble of claim 14.

[0003] A typical slot wall milling machine with a milling frame which carries milling wheels laterally below its base, the spaces between the teeth of which can be cleaned by means of reaming plates, is known from EP 3 543 408.

[0004] A typical diaphragm wall cutter is described, for example, in EP 1452645 A1 or EP 3 296 468. Rows of milling teeth are arranged along the circumference of the paired milling wheels. Axial spaces remain between the rows of milling teeth, into which so-called reaming plates engage. The reaming plates are located on the underside of the box-shaped housing and serve to scrape off cohesive soil material adhering to the milling teeth, which could impair milling performance, thus keeping the milling teeth free of cohesive soil material.

[0005] With the aforementioned diaphragm wall cutter, the excavated soil material remains in the ground and can be processed in situ with a supplied, setting slurry to form a so-called soil mortar. After hardening, the soil mortar can form a diaphragm wall segment in the created trench. Such diaphragm wall segments can be used to construct a cutoff wall or a perimeter wall, for example, for the enclosure of an excavation.

[0006] To create an in-situ soil mortar with the milled soil material, the box-shaped housing containing the drive unit of the generic diaphragm wall cutter is designed with smaller outer dimensions than the milled slot. This creates a space around the housing through which the milled soil material, mixed with the supplied hardening slurry by the milling wheels to form the soil mortar, can flow past the housing into an upper area of ​​the milled slot.

[0007] During operation of the trench cutter, the milling wheels are driven in opposite directions, so that the two pairs of milling wheels rotate inwards, thus conveying soil material into a central area below the cutter housing. The setting slurry can also be fed into this area to ensure a good mixing effect for the formation of the soil mortar.

[0008] With this type of inward-rotating drive of the milling wheels, the conveyance of the milled material past the housing can be hindered in certain soil types, particularly soil layers containing rock material. This can occur due to the comb-like reaming plates engaging between the milling teeth, for example, when coarser, hard rock material is present. In certain cases, this can lead to an undesirable increase in rotational resistance at the milling wheels and thus to increased power consumption. Damage to the reaming plates and the milling teeth can also result from this.

[0009] The invention is based on the Task The basis is to specify a slot wall milling machine and a method for creating a milled slot, which enables particularly efficient operation when creating a milled slot.

[0010] The problem is solved, firstly, by a slot wall milling machine with the features of claim 1 and, secondly, by a method with the features of claim 14. Preferred embodiments of the invention are specified in the dependent claims.

[0011] The slot wall milling machine according to the invention is characterized in that the at least one reaming plate is mounted on a plate holder at a distance from the housing, wherein a passage is formed between the at least one reaming plate and the housing, through which soil material milled off during operation can be conveyed upwards.

[0012] A fundamental aspect of the invention is to arrange the scraper plates not directly on the underside of the box-shaped housing, but rather at a distance from the housing on plate holders. The plate holders are arranged and designed such that the at least one scraper plate is positioned at a distance from the housing, creating a passage for the milled soil material. This passage allows the milled soil material, possibly accompanied by added suspension, to be guided past the scraper plates, particularly when the milling wheels are driven inwards, and thus flow upwards in a simplified manner. The hard rock material therefore does not need to be forced through the interlocking arrangement between the milling teeth and the scraper plates. Furthermore, the actual scraping action of the scraper plates is maintained even when soil material is adhering to them.The passage can have a size of a few centimeters up to approximately 40% of a milling wheel diameter in the horizontal longitudinal direction and a size up to the wheel width of a milling wheel in the horizontal width direction.

[0013] A preferred embodiment of the invention consists in the fact that at least two circumferential rows of milling teeth are arranged on the at least one milling wheel, which are axially spaced apart from one another by a circumferential clearance into which a broaching plate engages. In particular, more than two circumferential rows, especially four or five circumferential rows, can also be arranged on the milling wheel, each with a corresponding axial distance to the adjacent row of teeth. Corresponding to the existing clearances, which generally have an axial width of 2 to 10 cm, the broaching plates, which are fixed relative to the housing, engage in the circumferential clearances with the milling teeth driven by the milling wheel. The broaching plates can lightly contact the passing milling teeth and tooth holders, i.e., scrape them, or be spaced from them at a small axial distance, approximately a few millimeters.

[0014] According to the invention, the at least one milling wheel is mounted on a plate-shaped bearing plate on the underside of the housing, and the at least one broaching plate is attached to the bearing plate by means of the plate holder. The bearing plate can, in particular, incorporate a drive device for driving the milling wheels. The plate holder can be a simple support arm to which the broaching plates are attached. The support arm can be arranged transversely to the central plane of the bearing plate. Alternatively, an L-shaped or T-shaped plate holder can be attached to a side edge of the bearing plate or to the housing.

[0015] It is particularly preferred that two pairs of milling wheels are arranged on the underside of the housing. Each milling wheel of a milling wheel pair is arranged on one side of a common central bearing plate. The plate holders are arranged on the respective outer sides, so that the reaming plates can engage obliquely from the outside inwards into the circumferential clearances between the milling teeth.

[0016] Furthermore, it is particularly advantageous that one milling wheel from each pair is mounted on one side of the bearing plate and that each milling wheel is assigned at least one broaching plate, which is attached to the bearing plate via a plate holder. Preferably, several broaching plates for each milling wheel can be provided on each plate holder, corresponding to the number of clearances or gaps between the circumferential rows of the milling teeth.

[0017] According to a further embodiment of the invention, it is advantageous that each milling wheel is assigned a passage which is limited by the housing, the bearing plate and the associated at least one reaming plate with the plate holder.

[0018] This arrangement allows particularly harder rock material to avoid being forced through between the milling teeth with the tooth holders and the clearing plates by allowing the corresponding rock material to be diverted upwards through the passage.

[0019] According to a further development of the diaphragm wall cutter according to the invention, a feeding device for supplying a liquid, in particular a curable suspension such as a cement suspension, is provided. The suspension can be pumped from the surface to the diaphragm wall cutter in the milling slot by a suitable pumping device.

[0020] According to a further development of the invention, it is particularly advantageous for the feeding device to be arranged between two pairs of milling wheels and / or in at least one of the plate holders. The feeding device can be arranged in a generally known manner between the two pairs of milling wheels in a central area on the underside of the box-shaped housing. Alternatively or additionally, the feeding device can also be arranged on the at least one plate holder. The plate holder is at least partially hollow and incorporates a feeding channel. The feeding channel terminates in one or more outlet nozzles for the discharge of the liquid in the area of ​​the reaming plates. This improves the mixing effect and simultaneously facilitates the free flow of cohesive material at the milling teeth.

[0021] In principle, the arrangement of the reaming plates according to the invention can be used on various types of trench cutters via plate holders. According to one embodiment of the invention, it is particularly advantageous that the outer circumference of the housing is smaller than the milling cross-section of the milling wheels. This creates one or more areas along the housing, which form a passage or channel between the housing and the surrounding soil wall. This allows milled soil material, and in particular soil mortar produced by adding a setting liquid, to flow from the area of ​​the milling wheels past the housing of the cutter frame upwards into a section of the milled trench above the housing of the trench cutter.

[0022] In principle, the diaphragm wall cutter according to the invention can be driven in any suitable manner. According to a preferred embodiment of the invention, a drive unit, in particular a hydraulic motor or an electric motor, is arranged in the housing to drive the milling wheels. One or more central drive motors can thus be provided in the housing. Torque transmission can be effected in a generally known manner via a downward-extending drive shaft in the bearing plate and a corresponding gearbox in the bearing plate or on the milling wheels.

[0023] According to a further embodiment of the invention, it can be advantageous for the at least one milling wheel to have a hub in which a hub motor is arranged. The hub motor can also be a hydraulic motor or, preferably, an electric motor. In such an arrangement, the box-shaped housing can be used to accommodate other components or can be correspondingly reduced in size. A fundamentally frame-like construction of the housing is also possible.

[0024] Another preferred embodiment of the invention consists in the fact that the at least one broaching plate and / or the plate holder are detachably fastened, and a connecting device is provided on the underside of the housing with which at least one broaching plate can be directly attached to the housing. Depending on the desired milling type with a different drive direction of the milling wheels, a particularly flexible arrangement of the broaching plates can thus be achieved. In particular, the outer broaching plates arranged on the plate holder can be partially or completely removed if required. Alternatively or additionally, broaching plates can be attached directly to the underside of the housing in a generally known manner. Screw connections or other easily detachable connection types are particularly suitable as connecting devices.

[0025] The invention further comprises a diaphragm wall milling device with a carrier unit on which the diaphragm wall milling machine according to the invention is arranged to be vertically movable by means of a lifting device. The carrier unit can, in particular, be mobile, with a chassis, especially a tracked undercarriage, and a superstructure rotatably mounted thereon. A mast or a boom arm can be provided on the superstructure. A cable suspension or a rigid guide rod, which is adjustable along the mast, can be used as the lifting device.

[0026] The inventive method for creating a milling slot in the ground is characterized in that a diaphragm wall cutter or a diaphragm wall milling device according to the invention is used. A previously described diaphragm wall cutter or a previously described diaphragm wall milling device can be used. The advantages described above can be achieved when carrying out the method.

[0027] A preferred method variant according to the invention consists in the at least one milling wheel being driven in a rotary device, whereby milled soil material is guided by the at least one clearing plate through the passage between the housing and the clearing plate. Particularly when milling soil layers with harder rock inclusions, this avoids an increase in rotational resistance and the occurrence of damage that can arise from harder rock material being forced between the clearing plates and the milling teeth.

[0028] The invention is further described below with reference to preferred embodiments, which are shown schematically in the drawings. The drawings show: Fig. 1 a perspective view of a diaphragm wall milling device according to the invention; Fig. 2 a perspective enlarged and schematic representation of a diaphragm wall milling machine according to the invention; Fig. 3 a front view of the diaphragm wall milling machine according to the invention. Fig. 2 Fig. 4 shows a side view of the slot wall cutter according to the Figures 2 and 3 ; and Fig. 5 a schematic representation of the material flow during milling with a slot wall milling machine according to the invention.

[0029] A slot wall milling device 10 according to the invention with a carrier device 12 is in Figure 1The carrier device 12 can have a crawler-type undercarriage 14 on which a superstructure 16 can be rotatably mounted. A substantially vertical mast 18 can be adjustably mounted on the superstructure 18 via a linkage mechanism 17 with actuating cylinders. A guide rod 22 can extend along the mast 18 as part of a lifting device 20. A diaphragm wall cutter 30 according to the invention, which is described in more detail below, is attached to the lower end of the guide rod 22. The guide rod 22 can be moved vertically along the mast 18 via movable slides 24, which can be connected to the guide rod 22 via clamping cylinders, as part of the lifting device 20.

[0030] The in Figure 1The illustrated slot wall cutter 30 has two pairs of milling wheels 40, which are arranged parallel to each other with horizontally arranged axes of rotation. Milling teeth 44, indicated in a generally known manner, are attached to the outer circumference of the milling wheels 40.

[0031] The construction of a possible slot wall milling machine 30 according to the invention is described by way of example in connection with the Figures 2 to 4The slot wall milling machine 30 is shown in a highly schematic form, whereby, for the sake of clarity, individual milling teeth are not shown, but rather annular paths 45 or circumferential rows along which the milling teeth of a circumferential row move on the circumference of a milling wheel 40 when driven by a rotating motor. The milling teeth can be arranged on plate-shaped milling tooth holders (also not shown) and thus connected to a cylindrical hub 42 of the milling wheel 40. A hub motor for rotating the milling wheel 40 can be arranged inside the hub 42.

[0032] The tracks 45 or circumferential rows of milling teeth on each milling wheel 40 are axially spaced apart, with a circumferential clearance 46 between them. In the illustrated embodiment, three tracks 45 or circumferential rows with two intervening circumferential clearances 46 are provided on each milling wheel 40. A broaching plate 50 can engage in each of these circumferential clearances 46, extending almost to the outer circumference of the central hub 42. The broaching plates 50 are mounted radially outside the tracks 45 of the milling teeth on a plate holder 60 and are fixed relative to the rotating milling wheel 40. One plate holder 60 can be provided for each milling wheel 40.

[0033] Each pair of milling wheels 40 can be mounted on a plate-shaped bearing plate 34 located between the milling wheels 40, which is attached to the underside of a box-shaped housing 32. The respective plate holders 60 for the broaching plates 50 can also be attached to the bearing plate 34 for each pair of milling wheels 40. In the illustrated embodiment, the plate holders 60 have a retaining shaft 62 flanged to the bearing plate 34. A retaining bracket 64 can be attached to the retaining shaft 62, to which the broaching plates 50 for each milling wheel 50 can be detachably fastened, preferably by means of screw connections.

[0034] The plate holders 60, which preferably extend substantially parallel to the axes of rotation of the milling wheels 40, are arranged according to the invention at such a distance from the box-shaped housing 32 of the slot wall milling machine 30 that a clearance or passage 70 is formed between the respective plate holder 60 and the housing 32, as shown for example in the following diagram: Figure 3 can be seen from this.

[0035] A first feeding device 56 for feeding a binding suspension into the area between the milling wheels 40 can be provided on the underside of the housing 32, centrally located between the two plate-shaped bearing shields 34. Alternatively or additionally, one or more feeding devices can be provided in tubular retaining shafts 62.

[0036] The milling wheels 40 can be driven by a drive device (not shown in detail), which in the illustrated embodiment can be, in particular, hub motors in the hubs 42 of the milling wheels 40, such that they rotate inwards. This is shown in the illustration in the Figure 5 Indicated by arrows showing the direction of rotation.

[0037] When the milling wheels 40 are driven in this way according to Figure 5 During milling, soil material removed can be mixed into a soil mortar in the central area between the milling wheels 40 by means of a settable slurry. The removed soil material and the produced soil mortar can flow upwards through the respective passages 70 formed by the arrangement of the clearing plates 50 on the plate holders 60 spaced apart from the housing 32, as indicated by the flow arrows in the diagram. Figure 5The box-shaped housing 32 is smaller in its circumferential dimensions than a milling cross-section produced by the milling wheels 40.

[0038] The outer edges of the clearing plates 50 can be inclined inwards accordingly, so that the milled soil material and suspension flow upwards through the passage 70 between the plate holder 60 and the housing 32 is supported. This allows even larger rock fragments to be efficiently conveyed upwards past the housing 32 from the area of ​​the milling wheels 40, particularly when milling rocky or stony soil layers, thus reducing the risk of damage to the clearing plates 50 and milling teeth.

Claims

1. Trench cutter comprising - a box-shaped housing (32), on the upper face of which a lifting apparatus (20) can be mounted, - at least one cutting wheel (40), which is arranged on a lower face of the housing (32) and can be driven in rotation to remove soil material, wherein cutting teeth (44) are arranged along the outer circumference of the cutting wheel (40) in at least one circumferential row, which at least one axial circumferential clearance (46) adjoins, and - at least one clearing plate (50), which is fixedly arranged relative to the housing (32) and engages in the at least one circumferential clearance (46) on the cutting wheel (40) to clear away soil material, wherein the at least one cutting wheel (40) is mounted on a planar bearing plate (34) on the lower face of the housing (32), characterised in that the at least one clearing plate (50) with the plate holder (60) is mounted on the bearing plate (34), and - in that the at least one clearing plate (50) is mounted on the plate holder (60) so as to be spaced apart from the housing (32), which plate holder is arranged so as to be spaced apart from the housing (32), wherein a passage (70) is formed between the at least one clearing plate (50) mounted on the plate holder (60) and the housing (32), through which passage soil material that has been cut out during operation can be guided upwards.

2. Trench cutter according to claim 1, characterised in that at least two circumferential rows of cutting teeth (44) are arranged on the at least one cutting wheel (40), which teeth are axially spaced apart from one another by a circumferential clearance (46), in which a clearing plate (50) engages.

3. Trench cutter according to any of claims 1 or 2, characterised in that two pairs of cutting wheels (40) are arranged on the lower face of the housing (32).

4. Trench cutter according to claim 3, characterised in that from each pair of cutting wheels (40), one cutting wheel (40) is mounted on one side of the bearing plate (34) and in that at least one clearing plate (50), which is mounted on the bearing plate (34) by means of a plate holder (60), is assigned to each cutting wheel (40).

5. Trench cutter according to claim 4, characterised in that a passage (70), which is delimited by the housing (32), the bearing plate (34) and the assigned at least one clearing plate (50) with the plate holder (60), is assigned to each cutting wheel (40).

6. Trench cutter according to any one of claims 1 to 5, characterised in that a supply system (56) for supplying a liquid, in particular a curable suspension, is arranged.

7. Trench cutter according to claim 6, characterised in that the supply system (56) is arranged between two pairs of cutting wheels (40) and / or in at least one of the plate holders (60).

8. Trench cutter according to any one of claims 1 to 7, characterised in that an outer circumference of the housing (32) is smaller than a cutting cross section of the cutting wheels (40).

9. Trench cutter according to any one of claims 1 to 8, characterised in that a drive apparatus, in particular a hydraulic motor or an electric motor, is arranged in the housing (32) for driving the cutting wheels (40).

10. Trench cutter according to any one of claims 1 to 8, characterised in that the at least one cutting wheel (40) comprises a hub (42), in which a hub motor is arranged.

11. Trench cutter according to any one of claims 1 to 10, characterised in that the at least one clearing plate (50) and / or the plate holder (60) are detachably fastened and a connecting system for at least one clearing plate (50) is provided on the lower face of the housing (32).

12. Trench cutter device comprising a carrier equipment (12), on which a trench cutter (30) is arranged to be vertically movable by a lifting apparatus (20), characterised in that a trench cutter (30) according to any one of claims 1 to 11 is provided.

13. Method for making a cut trench in the ground, characterised in that a trench cutter (30) according to any one of claims 1 to 11 or a trench cutter device (10) according to claim 12 is used.

14. Method according to claim 13, characterised in that the at least one cutting wheel (40) is driven in rotation in a rotational direction, wherein cut-out soil material is guided through the passage (70) between the housing (32) and the clearing plate (50) by the at least one clearing plate (50).