Ground-working machine and method for producing wall panels

Abstract

The invention relates to a ground-working machine and a method for producing wall panels, with the ground-working machine having at least two elongate drilling and mixing tools arranged parallel to each other, which comprise a rod-form base body, on which a first screw conveyor and at least one second screw conveyor are arranged, the second screw conveyor being axially spaced apart from the first screw conveyor. According to the invention it is provided that at least on one drilling and mixing tool at a lower end the first screw conveyor is formed with an outer diameter that is greater than an outer diameter of the second screw conveyor which is arranged above the first screw conveyor.

Claims

1. A ground-working machine having at least two elongate drilling and mixing tools arranged parallel to each other, which comprise a rod-form base body, on which a lower first screw conveyor and at least one upper second screw conveyor are arranged, the at least one upper second screw conveyor being axially spaced apart from the lower first screw conveyor, wherein on at least one of the at least two elongate drilling and mixing tools, at a lower end of the lower first screw conveyor, the lower first screw conveyor is formed with an outer diameter that is greater than an outer diameter of the at least one upper second screw conveyor, which is arranged above the lower first screw conveyor, a first transverse yoke and a second transverse yoke are arranged between the lower first screw conveyor and the at least one upper second screw conveyor, the first transverse yoke and the second transverse yoke connecting the at least two elongate drilling and mixing tools to each other, between the at least two elongate drilling and mixing tools, a rod-form intermediate element is arranged, which has a third screw conveyor in an upper area of the rod-form intermediate element, the intermediate element has, at least in a lower area of the intermediate element, a smaller outer diameter than an outer diameter of the neighboring at least two elongate drilling and mixing tools, in a space between the first transverse yoke and the second transverse yoke, the at least two elongate drilling and mixing tools comprise a fourth screw conveyor, the intermediate element does not comprise a screw conveyor in the space between the first transverse yoke and the second transverse yoke, and the fourth screw conveyor has a diameter greater than that of the at least one upper second screw conveyor, and the lower area of the intermediate element is connected via the first transverse yoke and forms an exchangeable unit, which is releasably connected by an axial shaft connector.

2. The ground-working machine according to claim 1, wherein the lower first screw conveyor has a half to two spiral rotations.

3. The ground-working machine according to claim 2, wherein the lower first screw conveyor has a single spiral rotation.

4. The ground-working machine according to claim 1, wherein the at least two elongate drilling and mixing tools are rotatably mounted in the first transverse yoke and the second transverse yoke.

5. The ground-working machine according to claim 1, wherein at least in an area of the at least one upper second screw conveyor, mixing elements, agitating elements, or a combination of mixing elements and agitating elements are additionally arranged.

6. The ground-working machine according to claim 1, wherein a removal means for removing ground material is attached to a lower tip of the at least two elongate drilling and mixing tools.

7. The ground-working machine according to claim 1, wherein a mast is provided, along which a carriage is movably guided, and the at least two elongate drilling and mixing tools are rotatably mounted to the mast via the carriage.

8. The ground-working machine according to claim 7, wherein at least one rotary drive is arranged on the carriage for driving in rotation the at least two elongate drilling and mixing tools.

9. The ground-working machine according to claim 1, wherein a drivable carrier unit is provided.

10. A method for producing a wall panel in a ground with the ground-working machine according to claim 1, having the at least two elongate drilling and mixing tools arranged parallel to each other, which have the lower first screw conveyor and the at least one upper second screw conveyor, wherein the method comprises: driving the at least two elongate drilling and mixing tools in rotation and sinking the at least two elongate drilling and mixing tools into the ground, removing ground material mixing the removed ground material with an added binder suspension and forming a ground mortar, and setting the ground mortar to form the wall panel after the at least two elongate drilling and mixing tools have been pulled out of the ground, wherein via the use of the lower first screw conveyor on at least one of the elongate drilling and mixing tools, a bore diameter is produced that is greater than an outer diameter of the at least one upper second screw conveyor, wherein the at least one upper second screw conveyor is spaced apart from a bore wall.

11. The ground-working machine according to claim 1, wherein the axial shaft connector comprises spline groove teething.

Description

DESCRIPTION OF THE FIGURE

(1) The FIGURE shows a front view of a lower part of a ground-working machine.

DETAILED DESCRIPTION

(2) The invention is described in more detail below with the aid of a preferred exemplary embodiment, which is shown schematically in the drawing. The single drawing shows a front view of a lower part of a ground-working machine 10 according to the invention.

(3) The ground-working machine 10 according to the invention is constructed, with respect to the carrier unit that is not shown, with a mast, as known from EP 2 395 153 B1. Along the mast (not shown), in the ground-working machine 10 according to the invention, a tool unit 11 with two elongate drilling and mixing tools 20 is mounted so that it can be moved vertically. A central, rod-form intermediate element 30 is arranged between the two parallel orientated drilling and mixing tools 20.

(4) In the lower area shown, the two drilling and mixing tools 20 with the intermediate element 30 are coupled to each other via a lower first transverse yoke 12 and an upper second transverse yoke 14. In the first transverse yoke 12 and the second transverse yoke 14, the drilling and mixing tools 20 as well as the rod-form intermediate element 30 are each mounted rotatably via rotary bearings.

(5) In their lower area below the first transverse yoke 12, the two drilling and mixing tools 20 each have a lower first screw conveyor 24 on their rod-form base body 22. The first screw conveyor 24 thereby extends from a removal means 28 with ground removing teeth via a winding as far as the lower end of the first transverse yoke 12. In an upper area above the second transverse yoke 14, the two drilling and mixing tools 20 each have an upper second screw conveyor 26, which each have a plurality of windings. According to the invention an outer diameter of the lower first screw conveyor 24 is greater than an outer diameter of the upper second screw conveyor 26.

(6) Through the removal means 28 at the lower tips of the drilling and mixing tools 20, together with the lower first screw conveyor 24, a respective bore with a first bore diameter is created in the ground. Due to the larger outer diameter of the lower first screw conveyor 24, the upper second screw conveyors 26 with a smaller diameter do not contact the bore wall during drilling. Friction while drilling the bore is thus avoided, which has a positive effect on the drive power and the friction wear on the drilling and mixing tools 20.

(7) In order to interconnect the two bores formed by the drilling and working tools 20 spaced apart from each other to form an approximately oval drilling cross-section, the rod-form intermediate element 30 is also provided at its lower end with a removal means 28 with removal teeth. In its lower area the intermediate element 30 is held free from a screw conveyor. In an intermediate area between the first transverse yoke 12 and the second transverse yoke 14, further removal teeth 32 are arranged, which extend approximately radially relative to the axis of rotation of the intermediate element 30 outwards and downwards.

(8) In an upper area above the second transverse yoke 14 a tubular base body of the rod-form intermediate element 30 is provided with a screw conveyor 36. The screw conveyor 36 can have the same rotating direction and design as the second screw conveyor 26 of the drilling and mixing tool 20 on the right, whereas the second screw conveyor 26 of the drilling and mixing tool 20 on the left has an opposing spiral rotation. By means of at least one outlet opening 34 at the lower end of the tubular intermediate element 30, a binder suspension can be introduced, from outside the borehole, into the bore preferably under pressure. Through the rotating movement of the drilling and mixing tools 20 and the intermediate element 30, the ground material removed is mixed with the binder suspension, wherein a ground mortar is formed that sets. After withdrawal of the tool unit 11 from the borehole, the ground mortar can set to form a wall panel for a support or sealing wall.

(9) The area of the lower first screw conveyor 24 with the removal means 28 of the two drilling and mixing tools 20 is attached via a first connecting means 16 releasably to the rod-form base bodies 22. The first connecting means 16 is an axial shaft connection with spline groove teething. This lower area is connected via the first transverse yoke 12 with each other and constitutes an exchangeable unit.

(10) By means of a corresponding second connecting means 18 above the second transverse yoke 14, a further segment of the drilling and mixing tools 20 as well as the intermediate element 30 can be attached to the respective rod-form base bodies 22 in an easily releasable manner.