TRENCH CUTTER AND METHOD FOR FORMING A CUT TRENCH IN THE GROUND

Abstract

The invention relates to a trench cutter comprising a cutter frame, at least one rotatably drivable cutter wheel, which has cutting teeth on its outer circumference for removing ground material, at least one bearing shield, which is arranged on the underside of the cutter frame and is configured to support the at least one cutter wheel, at least one conveyor box, which has at least one opening for discharging removed ground material and/or for feeding a suspension and is arranged in the region of the at least one bearing shield, wherein the at least one cutter wheel has, on its side facing the bearing shield, at least one flap tooth which can be adjusted between an unfolded position, in which the flap tooth removes ground material below the bearing shield, and a folded position for running past at the bearing shield. According to the invention, it is provided that a conveying side facing the cutter wheel is provided on the conveyor box with at least one opening, past which the cutting teeth and the at least one flap tooth run with no or little distance, wherein a recess is formed on the conveying side with respect to adjacent regions for the at least one flap tooth to run past.

Claims

1. Trench cutter, comprising a cutter frame, at least one rotatably drivable cutter wheel, which has cutting teeth on its outer circumference for removing ground material, at least one bearing shield, which is arranged on the underside of the cutter frame and is configured to support the at least one cutter wheel, at least one conveyor box, which has at least one opening for discharging removed ground material and/or for feeding a suspension and is arranged in the region of the at least one bearing shield, wherein the at least one cutter wheel has at least one flap tooth on its side facing the bearing shield, which flap tooth is adjustable between an unfolded position, in which the flap tooth removes ground material below the bearing shield, and a folded position for running past the bearing shield, wherein a conveying side facing the cutter wheel is provided on the conveyor box with the at least one opening, past which the cutting teeth and the at least one flap tooth run with no or little distance, wherein a recess is formed on the conveying side with respect to adjacent regions for the at least one flap tooth to run past.

2. Trench cutter according to claim 1, wherein the at least one flap tooth protrudes radially with respect to fixed cutting teeth when running past at the conveying side of the conveyor box.

3. Trench cutter according to claim 1, wherein the bearing shield is configured plate-shaped, and in that a cutter wheel is mounted on each side of the bearing shield for forming a pair of cutter wheels.

4. Trench cutter according to claim 3, wherein two bearing shields, each with a pair of cutter wheels, are arranged on the underside of the cutter frame.

5. Trench cutter according to claim 1, wherein the at least one conveyor box is arranged centrally between two bearing shields.

6. Trench cutter according to claim 1, wherein the conveyor box is connected to a suction pump for discharging removed ground material via a suction line.

7. Trench cutter according to claim 1, wherein the conveyor box is connected to a feed device for feeding a suspension via a feed line.

8. Trench cutter according to claim 1, wherein the conveyor box has a wedge-shaped, downward-facing portion with wedge surfaces which form the conveying side on both sides with at least one opening in each case.

9. Trench cutter according to claim 1, wherein multiple openings are provided on the conveying side.

10. Trench cutter according to claim 1, wherein at least one wear plate is arranged on the conveying side, and in that, in order to form the recess, the wear plate has a reduced thickness in the region of the recess or is omitted in this region.

11. Trench cutter according to claim 1, wherein when a pair of cutter wheels is arranged on a bearing shield, a common recess is formed on the conveying side of the conveyor box for the flap teeth of the two cutter wheels.

12. Trench cutter according to claim 1, wherein the at least one flap tooth, in its unfolded position, has an angle smaller than or equal to 45 relative to a center plane of the bearing shield.

13. Method for forming a cut trench in the ground, wherein a trench cutter according to claim 1 is used.

Description

[0028] The invention is explained in greater detail below with reference to preferred exemplary embodiments, which are shown schematically in the drawings. Shown are in:

[0029] FIG. 1 a schematic perspective view of a lower region of a trench cutter according to the invention;

[0030] FIG. 2 a side view of the trench cutter of FIG. 1;

[0031] FIG. 3 a detail view of the arrangement of a bearing shield, a flap tooth and a conveyor box;

[0032] FIG. 4 a cross-sectional view according to section A-A of FIG. 3;

[0033] FIG. 5 a schematic illustration of the trench cutter according to the invention with an unfolded flap tooth and the worked-off ground region; and

[0034] FIG. 6 an illustration corresponding to FIG. 5 for a conventional trench cutter.

[0035] FIGS. 1 and 2 show in a schematic illustration a trench cutter 10 according to the invention with a cutter frame 12 which is only strongly schematically indicated and on the underside of which two bearing shields 14 are arranged next to each other. A cutter wheel 30 can be rotatably mounted on each plate-shaped bearing shield 14 on each side. The cutter wheels 30 are driven in rotation by a drive device, not shown, which may comprise a hub drive inside each of the cutter wheels 30 or a drive motor on the cutter frame 12 with a gear arrangement in the bearing shield 14, for removing ground material. Fixed cutting teeth, not shown, are arranged on the outer circumference of the cutter wheels 30 in a manner known per se.

[0036] A conveyor box 20, preferably directed parallel to the axes of the cutter wheels 30, can be arranged between the two bearing shields 14 on the underside of the cutter frame 12. In the illustrated embodiment, the conveyor box 20 comprises a base body 22 with a wedge-shaped, downward-facing portion 23. A conveying side 24 with openings 28 may be arranged on each of the wedge surfaces of the wedge-shaped portion 23. The conveyor box 20 may be designed as a suction box, which can be line-connected to a suction pump, not shown, on the cutter frame 12. Via the openings 28, removed ground material with surrounding liquid can thus be suctioned into the openings 28 and discharged upwards through the cutter frame 12.

[0037] According to the invention, a recess 26 is formed on the conveying sides 24 of the conveyor box 20 for flap teeth 40 to run past the cutter wheels 30. In the illustrated exemplary embodiments, the recess 26 is formed by applying a wear plate 25 to the remaining regions of the conveying side 24, which is omitted in the region of the recess 26.

[0038] As can be seen particularly well from the side view of FIG. 2, the flap teeth 40 on the cutter wheels 30 are designed in such a way that they protrude into the region of the recess 26 on the conveyor box 20. The flap teeth 40 can be formed with such a length that they run past the conveyor box 20 at the bottom of the recess 26 with a small distance, which is preferably smaller than a thickness of the wear plate 25, or, in particular contact and scratch it slightly. In this way, the openings 28 in the region of the recess 26 can be kept free from clogging, for example by rock material, by the flap teeth 40. The conveying teeth, not illustrated, on the cutter wheels 30 may be designed with a corresponding fixed length so that they run past at the protruding wear plates 25 with a corresponding small clearance or also contact and scratch them easily.

[0039] This arrangement and configuration of the flap teeth 40 is particularly apparent from FIGS. 3 and 4. In particular, in FIG. 4, the flap tooth 40, which may be received in a tooth holder 42 that is pivotally mounted on the cutter wheel 30 about a pivot axis 32, is shown in a folded position in which the flap tooth 40 is aligned and spaced apart from the bearing shield 14. In this folded position, the flap tooth 40 can slightly contact the bottom of the recess 26 on the conveyor box 20 to clear the opening 28 in the region of the recess 26 when the cutter wheels 30 are rotated.

[0040] Due to the recess 26 provided on the conveyor box 20 according to the invention, the flap tooth 40 can be formed with a greater length. According to FIG. 5, a flap tooth designed according to the invention is shown in its unfolded position on the cutter wheel 30, whereby the flap tooth 40 can remove ground material below the bearing shield 14 and assumes an angle a with respect to a center plane 16 of the bearing shield 14. Depending on the length of the flap tooth 40, a material ridge 7 remains below the bearing shield 14 at the cutting base 5 of the ground 3. This also extends across the cutting cross section up into the side wall of the cut trench. In its unfolded position according to FIG. 5, the flap tooth 40 should extend at least as far as the center plane 16 of the bearing shield 14, since the opposite bottom region is removed by the flap tooth 40 of the opposite cutter wheel 30, which is not shown in FIG. 5. The longer the flap tooth 40, the smaller the setting angle a relative to the center plane 16 and the smaller and flatter the remaining material ridge 7 on the cutting base 5 and correspondingly on the side wall.

[0041] This becomes clear in comparison with the schematic illustration of a conventional trench cutter according to FIG. 6. The illustration according to FIG. 6 corresponds in principle to the illustration of FIG. 5, but wherein a conventional flap tooth 40 is designed shorter. The material ridge 7 remaining on the cutting base 5 is correspondingly larger and more solid in the case of a conventional trench cutter.