Improved soil cutting device and drum with forwardly inclined cutting element

Abstract

A device for making a vertical retaining wall and/or foundation includes a frame with a substantially vertically movable outer end, and a cutting frame mounted close to the outer end. The cutting frame has at least one pair of drums rotatable about respective rotation axes that lies parallel to each other so the drums can rotate adjacently of each other. An outer surface of each drum has at least one row with at least five cutter holders extending radially from the outer surface. Each cutter holder has at least one cutting element extending away from the outer surface and having a stop surface which has an angle with a centre line which intersects the rotation axis of the corresponding drum and a centre of the corresponding cutter holder at the outer surface. The drums are driveable to dislodge soil while the outer end is driven into the soil.

1 . A device for making a vertical retaining wall and/or foundation, comprising:
 a frame with a substantially vertically movable outer end;   a cutting frame mounted close to the outer end, wherein the cutting frame is provided with at least one pair of drums which are each rotatable about a respective rotation axis, wherein the rotation axes of the at least one pair of drums lie parallel to and at a distance from each other so that the drums can rotate adjacently of each other as seen in a plane perpendicularly of the rotation axes, wherein an outer surface of each of the drums is provided along the periphery thereof with at least one row with at least five cutter holders extending from the outer surface in a substantially radial direction, wherein each cutter holder comprises at least one cutting element extending away from the outer surface and having a stop surface which has an angle with a centre line which intersects the rotation axis of the corresponding drum and a centre of the corresponding cutter holder at the position of the outer surface; wherein the at least one pair of drums are rotatingly driveable for the purpose of dislodging soil while the outer end is driven into the soil.   
     
     
         2 . The device according to  claim 1 , wherein the angle is greater than 5°. 
     
     
         3 . The device according to  claim 1 , wherein the at least five cutter holders are distributed uniformly over the same peripheral line of the outer surface. 
     
     
         4 . The device according to  claim 1 , wherein the outer surface is further provided with at least three rows with five cutter holders each, wherein the rows lie at a mutual distance as seen in a longitudinal direction of the drum, and wherein the cutter holders of adjacent rows have a mutual angle at the centre, measured between a corresponding front edge of the cutter holders. 
     
     
         5 . The device according to  claim 4 , wherein the angle at the centre is greater than 10°. 
     
     
         6 . The device according to  claim 4 , wherein a proximal base of each cutter holder whereby the cutter holder is connected to the outer surface extends along the outer surface over a minimum arc length so that a front edge of each cutter holder at least partially overlaps a rear edge of a cutter holder of an adjacent row, as seen in a plane perpendicularly of the rotation axis. 
     
     
         7 . The device according to  claim 4 , wherein the cutting frame further comprises at least one clearing plate between each row, wherein the clearing plate is arranged at a distance from each of the cutting elements and extends up to a maximum radial distance from the outer surface. 
     
     
         8 . The device according to  claim 7 , wherein the at least one clearing plate is provided at the position of a stop edge thereof with one or more protrusions. 
     
     
         9 . The device according to  claim 4 , wherein provided on the outer surface between one or more rows are one or more teeth which extend in a substantially radial direction from the outer surface over a distance which is smaller than a maximum dimension, as measured from the outer surface, of the cutter holders. 
     
     
         10 . The device according to  claim 1 , wherein provided at the position of the distal outer end of the cutter holder ( 120 ) is a slot in which a cutting element is arrangeable, wherein a wall of the slot is provided with at least one locking groove and wherein the cutting element comprises a passage opening which, when the cutting element is arranged in the slot, is provided to be aligned with the at least one locking groove, wherein the cutter holder further comprises a fastening means which is provided to extend through the passage opening and the at least one locking groove in order to fix the cutting element in the cutter holder. 
     
     
         11 . The device according to  claim 1 , wherein a width of a cutter holder is smaller than a width of the stop surface of the cutting element. 
     
     
         12 . The device according to  claim 1 , wherein the cutter holders of the row lying adjacently of a base of the drum comprise cutting elements, the stop surface of which protrudes beyond the base. 
     
     
         13 . The device according to  claim 1 , wherein the vertically movable outer end is a substantially vertical tube on which the cutting frame is mounted. 
     
     
         14 . The device according to  claim 1 , further comprising a mortar injecting device which is provided in the cutting frame and is configured to inject a mortar between the drums during dislodging of the soil. 
     
     
         15 . The device according to  claim 1 , wherein the at least one pair of drums are rotatingly driveable in opposite direction. 
     
     
         16 . The device according to  claim 1 , wherein each cutter holder is provided at least partially with a thickened portion at the position of a stop edge thereof, wherein the thickened portion has a width, as measured in a transverse direction, which is greater than a width of the cutter holder. 
     
     
         17 . The device according to  claim 16 , wherein the thickened portion is provided over the whole stop edge. 
     
     
         18 . The device according to  claim 1 , wherein one or more side walls of each cutter holder are provided with one or more protrusions extending away from the side wall over a predetermined distance. 
     
     
         19 . The device according to  claim 17 , wherein the one or more protrusions are positioned close to the stop edge of the cutter holder. 
     
     
         20 - 35 . (canceled)