TRENCH CUTTER

Abstract

The disclosure relates to a trench cutter having at least one bearing shield, at least one cutting wheel rotatably mounted on the bearing shield for breaking up soil material, and a suction box arranged radially adjacent to the cutting wheel for sucking liquid containing soil material. At least one adjustable cutting tool is arranged on the cutting wheel where as the cutting wheel rotates, it moves between a folded-in position, which is an axial distance from the bearing shield and can be moved past it, and a folded-out position, which it projects into an area radially adjacent to the bearing shield. The suction box has a recess where in the folded-out position or in the transition between the folded-in position and the folded-out position, the cutting tool moves through the recess. The disclosure also relates to a carrier machine, in particular a cable excavator, having a trench cutter.

Claims

1. A trench cutter, comprising at least one bearing shield, at least one cutting wheel rotatably mounted on the bearing shield for breaking up soil material, and a suction box arranged radially adjacent to the cutting wheel for sucking up liquid containing soil material, wherein at least one adjustable cutting tool is arranged on the cutting wheel and is designed in such a way that as the cutting wheel rotates, it moves between a folded-in position, in which it is an axial distance from the bearing shield and can be moved past it, and a folded-out position, in which it projects into an area radially adjacent to the bearing shield, wherein the suction box has a recess which is designed in such a way that, in the folded-out position or in the transition between the folded-in position and the folded-out position, the adjustable cutting tool moves through the recess.

2. The trench cutter according to claim 1, wherein, as the cutting wheel rotates, an end of the adjustable cutting tool spaced radially apart from the cutting wheel describes a trajectory which passes through the recess and crosses a notional radial extension of the bearing shield.

3. The trench cutter according to claim 1, wherein when the trench cutter is in cutting mode, the recess is positioned ahead in the direction of rotation of the cutting wheel with respect to a first angular sector in which the adjustable cutting tool is in the folded-in position.

4. The trench cutter according to claim 1, wherein the adjustable cutting tool is pivotably mounted on the cutting wheel.

5. The trench cutter according to claim 1, wherein, in addition to the at least one adjustable cutting tool, the cutting wheel has at least one non-adjustable cutting tool, which is a greater axial distance from the bearing shield than the at least one adjustable cutting tool.

6. The trench cutter according to claim 5, wherein the at least one adjustable cutting tool is longer than the at least one non-adjustable cutting tool.

7. The trench cutter according to claim 6, wherein the suction box has a suction surface which faces the outer circumference of the cutting wheel and has at least one suction opening, a plurality of suction openings arranged side by side in the axial direction, wherein the recess is formed on the suction surface.

8. The trench cutter according to claim 7, wherein the recess is arranged in the circumferential direction in the vicinity of the at least one suction opening.

9. The trench cutter according to claim 1, wherein the recess is at the axial height of the bearing shield, wherein a notional median plane of the bearing shield divides the recess symmetrically.

10. The trench cutter according to claim 1, wherein the recess is substantially rectangular in shape, wherein at least two edges of the recess are bevelled.

11. The trench cutter according to claim 1, comprising an adjusting device with which the at least one adjustable cutting tool can be moved between the folded-in position and the folded-out position as the cutting wheel rotates, wherein the adjusting device includes a control cam, which is arranged on the bearing shield and makes contact with the adjustable cutting tool as it passes, thereby moving it into the folded-in or folded-out position, wherein the control cam is bevelled in a run-in area and/or in a run-out area.

12. The trench cutter according to claim 6, comprising two bearing shields, each having at least one rotatably mounted cutting wheel, wherein the cutting wheels are arranged radially side by side, wherein the suction box is arranged between the cutting wheels and has at least two recesses, each facing one of the cutting wheels.

13. The trench cutter according to claim 12, wherein a cutting wheel is arranged on each opposing side of the bearing shield, wherein the cutting wheels are coaxially mounted and each have at least one adjustable cutting tool.

14. The trench cutter according to claim 12, wherein a common suction box is provided for the cutting wheels arranged on the bearing shield, wherein the suction box has a common recess for the adjustable cutting tools of the coaxial cutting wheels.

15. A a cable excavator having a trench cutter according to claim 1.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0033] Further features, details and advantages of the disclosure can be found in the exemplary embodiments below, illustrated by way of the figures. In the figures:

[0034] FIG. 1 shows an exemplary embodiment of the trench cutter according to the disclosure in a schematic front view;

[0035] FIG. 2 shows the suction box in a perspective view;

[0036] FIG. 3 shows a perspective view of the lower part of the trench cutter with cutting wheels and suction box;

[0037] FIG. 4 shows a detailed side view of the area between the suction box and the cutting wheel; and

[0038] FIG. 5 shows a detailed perspective view of the area between the suction box and the cutting wheel.

DETAILED DESCRIPTION

[0039] FIG. 1 shows a schematic view of an exemplary embodiment of the trench cutter 10 according to the disclosure, looking at the front side thereof. The trench cutter 10 illustrated in this exemplary embodiment comprises a cutter frame 11 with three frame parts, which can be releasably connected to one another. Alternatively, the cutter frame 11 can comprise a larger or smaller number of frame parts or can be formed in one piece. The trench cutter 10 can be suspended by the upper side of the cutter frame 11 from a carrier machine, which is not shown here.

[0040] At the bottom end of the cutter frame 11 there are two pairs of cutting wheels 14 (shown only schematically here) for removing and breaking up soil material. The cutting wheels 14 shown here are arranged side by side in the radial direction. There is an additional pair of cutting wheels on the rear side, which is not visible here because it is concealed. The cutting wheels 14 are rotatably mounted on bearing shields 12, which are attached to the underside of the cutter frame 11.

[0041] In an area between the cutting wheels 14 of a cutting wheel pair and above the horizontal plane formed by the rotary axes of the cutting wheels 14 (when the trench cutter 10 is in the upright position) there is a suction box 20. This has an elongated shape and runs parallel to the rotary axes of the cutting wheels 14 from one side of the trench cutter 10 with one pair of cutting wheels to the opposite side with the other pair of cutting wheels. A common suction box 20 is preferably used for both pairs of cutting wheels. In the exemplary embodiment shown here, there is a bearing shield 12 with two coaxially arranged cutting wheels 14 on either side of the suction box 20.

[0042] The suction box 20, an enlarged version of which is shown in FIG. 2 in a perspective view, serves to suck the waste material/liquid suspension out of the trench by means of a mud pump (not illustrated). The suction box 20 has a box-shaped, symmetrical design and is preferably mounted on the underside of the cutter frame 11 by way of an attachment plate.

[0043] The suction box 20 has two lateral bevelled suction surfaces 24 which face the respective cutting wheels 14 and are located opposite the outer circumferential surfaces thereof. The suction surfaces 24 taper towards each other and can be oriented substantially tangentially to the respective cutting wheels 14. As can be seen in FIG. 2, a plurality of suction openings 25 are arranged side by side on the suction surfaces 24 and are connected via an interior volume of the suction box 20 to a mud pump, which is arranged on or in the cutter frame 11 and pumps the extracted suspension through a suction line (not shown here) running inside the cutter frame 11 to a treatment plant.

[0044] FIG. 3 shows a perspective view of the lower part of the trench cutter 10, with the suction box 20 and the cutting wheels 14 arranged next to it on both sides. As can be seen here, a plurality of cutting tools 30, 32 for removing and breaking up soil material are arranged on the outer circumferential surfaces of the cutting wheels 14. These cutting tools 30, 32 can also be described as crushing tools, and in the exemplary embodiment shown here they are designed as flat cutting teeth 30, 32, which comprise a main body 33 and a blade 34 secured therein (see FIG. 4). Alternatively, the cutting tools 30, 32 can be designed as cutting teeth with conical tips, for example.

[0045] FIG. 3 also shows one of the flat bearing shields 12, on which two cutting wheels 14 are rotatably mounted. In the exemplary embodiment shown here, the bearing shield 12 has bevels 13 on the lateral end remote from the suction box 20, such that in this area the bearing shield 12 narrows towards the median plane running through the centre of the bearing shield 12.

[0046] As the respective cutting wheel 14 rotates, the cutting teeth 30, 32 must be moved past both the suction surface 24 of the suction box 20 and the bearing shield 12 without a collision occurring. The distance from the suction surface 24 to the outer circumferential surface of the cutting wheel 14 thus determines the maximum radial length of the cutting teeth 32. In order for soil material also to be removed from between the cutting wheels 14, in an area adjoining the narrow sides of the bearing shield 12, the outer cutting teeth 30, which run directly past the bearing shield 12, are not fixedly arranged on the cutting wheel 14 but instead are adjustable. These adjustable cutting teeth 30 can pivot about a rotary axis between a folded-in position and a folded-out position and can thus also be described as hinged teeth 30. By contrast, the other cutting teeth 32 are immovably or fixedly attached to the cutting wheel 14.

[0047] In the folded-in position, these adjustable cutting teeth 30 are pivoted away from the bearing shield 12 so they can be moved past it without collision. In the folded-out position, the adjustable cutting teeth 30 are pivoted out or folded out towards the bearing shield 12, so the blades 34 project into the area next to or below the bearing shield 12 and clear away soil material in that area. In FIG. 3, two adjustable cutting teeth 30 are shown in the folded-out position. The folding in and out can be achieved in a manner known per se, by contact with a cam guide (not shown) arranged on the bearing shield 12.

[0048] The length of the adjustable cutting teeth 30 and the thickness of the bearing shield 12 determine the quantity of material that can be removed in the area between the cutting wheels 14 and the size of the remaining ridge of soil material that is not removed. The thickness of the bearing shield 12 is determined in particular here by the intended use and the structural requirements of the system. The system-related excess soil material or ridge in the longitudinal direction of the trench cutter 10 (defined here as a direction parallel to the line connecting the rotary axes of the cutting wheels 14 arranged on either side of the suction box 20) leads to a reduction in the clearance between the trench cutter 10 and the lateral walls of the trench. This can lead to a reduction in the sliding properties of the trench cutter 10, leading to increased wear and poorer controllability of the trench cutter 10.

[0049] To minimise this excess material, the adjustable cutting teeth 30 are longer than the fixed cutting teeth 32, so they project further into the area next to or below the bearing shield 12 and remove more material in that area. Since this would lead to a collision with the suction box 20, the latter has, in accordance with the disclosure, a recess 22 (see FIG. 2) on each of the suction surfaces 24, into which recess the adjustable cutting teeth 30 dip or project as they move past it. In this process, the outermost ends of the blades 34 of the cutting teeth 30 describe trajectories which pass through the recesses 22 of the suction box 20. By reason of the recesses 22 provided in accordance with the disclosure, the adjustable cutting teeth 30 that in the vicinity of the suction box 20 are still in the folded-out position or are in the transition between the folded-out and folded-in position do not collide with the suction surfaces 24 of the suction box 20. If the cutting wheels 14 are rotated in reverse, the adjustable cutting teeth 30 can pivot from the folded-in to the folded-out position in the vicinity of the recess 22.

[0050] The recess 22 in the suction box 20 allows the adjustable cutting teeth 30 to be made significantly longer, so the removal of material from between the cutting wheels 14 or radially adjacent to the bearing shield 12 can be increased and the controllability of the trench cutter 10 can thus be improved. In particular, the recess 22 maximises the removal of material from between the cutting wheels 14, even with a thick bearing shield 12, making the shield universally usable (i.e. a single bearing shield 12 for multiple slurry wall dimensions).

[0051] In the exemplary embodiment shown in FIG. 2, each suction surface 24 features a single central recess 22 located midway between the end faces of the suction box 20, so the adjustable cutting teeth 30 of both cutting wheels 14 of the respective bearing shield 12 dip into the common recess 22. The recess 22 can in general have a rectangular shape, as shown here, and can optionally also have bevelled edges. Other shapes are also possible, however. In addition, there can also be a suction opening 25 in the vicinity of the recess 22 (see FIG. 2).

[0052] In the exemplary embodiment of FIG. 2, the suction box 20 has a wear plate attached to the sheet metal structure of the suction box 20 on the outside of the suction side 24. Here, the recess 22 is formed by hollowing out the wear plate down to the underlying sheet metal casing of the suction box 20. Alternatively, the recess 22 could be formed directly in the sheet metal structure of the suction box 20, for example by way of a corresponding cut-out or indentation in the casing of the suction box 20.

[0053] FIGS. 4 and 5 show detailed views of the area between one of the suction sides 24 of the suction box 20 and one of the adjoining cutting wheels 14, wherein FIG. 4 shows a side view looking at the end faces of the suction box 20 and the cutting wheel 14 and FIG. 5 shows a perspective view. It can be seen in FIG. 4 that the adjustable cutting tooth 30 dips into the suction box 20 while the other, fixed cutting teeth 14 are short enough to be moved past the suction box 20 without collision. The recess 22 can be seen in FIG. 5.

[0054] In addition, in the embodiment shown here, a plurality of attachment elements 26 arranged on the side of the suction box 20 above the suction openings 25 serve for the attachment of additional elements (not shown here), such as dividing plates, to the suction box 20. These attachment elements 26 do not necessarily have to be present, however.

[0055] Instead of a design with a common suction box 20 for both pairs of cutting wheels, a separate suction box 20 can be provided for each pair of cutting wheels, each with its own recess 22 on each suction surface 24.

LIST OF REFERENCE SIGNS

[0056] 10 Trench cutter [0057] 11 Cutter frame [0058] 12 Bearing shield [0059] 13 Bevel [0060] 14 Cutting wheel [0061] 20 Suction box [0062] 22 Recess [0063] 24 Suction surface [0064] 25 Suction opening [0065] 26 Attachment element [0066] 30 Adjustable cutting tool [0067] 32 Non-adjustable cutting tool [0068] 33 Main body [0069] 34 Blade