Patent Publication Number: US-2023147209-A1

Title: Drill head and method for producing a vertical borehole in the ground

Description:
The invention relates to a drill head and to a method for producing a substantially vertical borehole in the ground, in particular for producing a shaft, having a body which is able to be connected to a rotary drive of a drilling device, having drilling tools which for loosening the ground at a face of the borehole are disposed on the body, having a discharge device which for discharging the loosened ground on the face is able to be connected to a suction unit for suctioning a conveying medium by way of a conveying line, wherein the discharge device has an opening region which is disposed on the body and has at least one opening in the region of the drilling tools at the face. 
     Such a drill head is known from, for example, U.S. Pat. No. 4,646,853 A, EP 2597249 B1, U.S. Pat. Nos. 3,384,191 A, 4,195,700 A and 4,200,160 A. 
     U.S. Pat. No. 4,646,853 A discloses a device and a method for sinking a shaft. A cutting wheel which is rotatable about a vertical axis is provided for loosening the ground. Mechanical conveying by buckets is provided for discharging the loosened ground. 
     EP 2597249 B1 shows a drilling device for establishing vertical boreholes in the soil, having a drill head which rotates on a face. A suction system is provided which has an opening which is disposed externally on the end of the drill head that faces the face and rotates conjointly with the drill head. Loosened ground is discharged from the borehole here. 
     U.S. Pat. No. 3,384,191 A shows a drill head which has roller chisels and likewise has a suction system for discharging the loosened ground. Provided to this end is a guide plate which is disposed in the region of the opening of the suction system and collects the loosened ground during the rotation of the drill head and feeds said loosened ground to the opening. An oblique duct which opens into a centrically disposed discharge line is disposed behind the opening. 
     U.S. Pat. No. 4,195,700 A likewise discloses a drill head which has roller chisels and which has a radial opening, a discharge line being provided at the inner end of said drill head. The opening is embodied as a slot behind which a conically shaped tube that widens toward the discharge line is provided. 
     U.S. Pat. No. 4,200,160 A discloses a drill head which has a suction system for discharging the loosened ground. The suction system provides a slot-shaped radial opening which opens into a cylindrical space. A duct which leads into the waste water line emanates from said cylindrical space. 
     It is an object of the invention to simplify the suction system in the abovementioned drill heads and to simultaneously improve said suction systems in terms of their performance. 
     In terms of the drill head, the object is achieved in that the at least one opening of the opening region is connected to a suction box which as a component part of the discharge device has, at an end opposite the opening, a connector opening for connecting to the conveying line, in that at least one element which exerts an acceleration on the loosened ground in the region of the suction box is provided, by way of which acceleration the ground loosened by the drilling tools is able to be moved into the opening region and/or through the opening into the suction box, wherein the loosened ground is acquired by the conveying medium in the opening region, preferably in the opening and/or in the suction box, and is able to be discharged by way of the conveying line by the suction unit. 
     As a result thereof, it becomes possible in a surprisingly simple manner to discharge the loosened ground, in particular in the case of comparatively heavy, inertial component parts which are not readily suctionable, and at the same time to significantly increase the suction output. 
     A further teaching of the invention provides that the at least one element is at least one nozzle which is provided so as to be directed into the opening region and dispenses at least one jet of a transport medium so as to effect the acceleration. 
     A further teaching of the invention provides that at least one deflection region, in which the flow direction of the loosened ground is able to be deflected, is provided behind the opening, preferably prior to entering the suction box. As a result thereof, the material to be discharged can be fed to the discharge and subsequently be discharged in a particularly simple manner. 
     A further teaching of the invention provides that at least one tool, preferably in the form of a toothed bar, for loosening the ground and/or for picking up loosened ground, is provided in the opening region. As a result thereof, loosening/picking-up of rock/ground at the face can be performed directly in the opening region. The material thus loosened/picked up can be fed to the suction unit in a particularly positive manner. 
     It is furthermore advantageous that the at least one tool is able to be moved for changing the spacing of the tool from the face, preferably by way of at least one hydraulic cylinder, and/or that the at least one tool is pivotable in relation to the opening region, preferably by way of at least one hydraulic cylinder. 
     A further teaching of the invention provides that the spacing of the opening region from the face is adjustable. It is advantageous here that the adjustment of the spacing takes place by vertically moving the suction box and/or by pivoting the suction box about a pivot point, wherein a drive, preferably a hydraulic cylinder or a spring mechanism, is provided for moving or pivoting. As a result thereof, the quantity of the suctioned material is thus able to be influenced directly in a simple manner. 
     A further teaching of the invention provides that the opening region is provided with a cleaning tool, preferably at least one movable element and/or at least one nozzle for dispensing a medium, for example a gas (air) or a liquid (water, bentonite purge). As a result thereof, obstructions in the opening region can either be eliminated or prevented. 
     A further teaching of the invention provides that at least one purging nozzle is provided by way of which ground loosened by at least one drilling tool is able to be transported into a region on the face that is traveled across by the suction box when drilling with the drill head. As a result thereof, the transportation of material toward the suction box is improved in a simple manner. 
     A further teaching of the invention provides that the suction box is provided so as to be replaceable in the drill head. As a result thereof, the drill head can be readily adapted to different geological conditions. Furthermore, a reversal of the rotating direction is also possible. 
     A further teaching of the invention provides that a classifying element is provided in the opening region. This can be, for example, a mesh, separators which divide the opening region into a plurality of openings, or else a plurality of openings. As a result thereof, it becomes possible to achieve in a simple manner a limitation in terms of the grain size of the suctioned material. 
     A further teaching of the invention provides that the suction box is disposed so as to be substantially horizontal. As a result thereof, the transportation of material in the suction box and the pick-up of material are positively influenced. 
     A further teaching of the invention provides that the opening region, when viewed from the center, extends in a substantially radially outward manner. It is advantageous here for the opening to be embodied in an elongate manner, or in the manner of a slot, respectively. A further teaching of the invention provides that the available cross section of the opening, when viewed in a radially outward manner, varies along the opening region, preferably increases along the latter. As a result thereof, the pick-up of material, the location of the material pick-up, as well as the picked up quantity can be influenced in a simple manner. 
     It is furthermore advantageous that the connector opening of the suction box, in terms of the opening region, is disposed so as to be offset, preferably in an outward manner, in relation to a perpendicular bisector of the opening region. As a result thereof, the suction box is of an asymmetrical construction. The suction intensity, or the flow profile, respectively, in the suction box or in the opening region can be influenced in a simple manner so that the suctioned quantity of material is able to be influenced. For example, the flow in that region of the suction box that, when viewed radially, is on the outside can be increased by way of an outward displacement so as to be better able to suction the larger quantity of material arising there. 
     A further teaching of the invention provides that the connector opening of the suction box, in terms of the opening region, is disposed so as to be pivoted in relation to a perpendicular bisector of the opening region. The suction intensity, or the flow profile, respectively, in the suction box or in the opening region can be influenced in a simple manner so that the suctioned quantity of material is able to be influenced. For example, the flow in that region of the suction box that, when viewed radially, is on the outside can be increased by way of an inward tilting of the connector opening, so as to be better able to suction the larger quantity of material arising there. 
     A further teaching of the invention provides that the suction box has at least one nozzle in the interior space. As a result thereof, the movement of the loosened ground/rock for acquisition by the conveying medium can be improved in a simple manner. 
     A further teaching of the invention provides that the conveying medium and/or the transport medium is a liquid or gaseous medium, preferably water, a bentonite suspension, or air. A particularly preferred combination here is that the conveying medium is air and the transport medium is air or a liquid, preferably water. This is applied when the drill head is not flooded, is not to be flooded, or cannot be flooded, and liquid-based conveying is thus precluded. It has been surprisingly demonstrated that the loosened ground/the loosened rock is readily able to be transported/activated by the dispensed jet and is able to be advantageously fed to and discharged by the conveying flow of air. 
     A further teaching of the invention provides that the at least one element is at least one driven rotary element having at least one impact element disposed thereon, wherein the at least one impact element, by way of a rotating movement, effects the acceleration of the loosened ground by contacting the latter. 
     It is advantageous here that the impact element is movable on an impact circle which is provided so as to be concentric about the rotary element. 
     A further teaching of the invention provides that the at least one impact element, preferably by way of a joint, is movably disposed on the at least one rotary element. 
     A further teaching of the invention provides that the at least one impact element is a hammer, a blade, a cable, a chain, a brush element, or a chisel. 
     A further teaching of the invention provides that the rotation of the at least one rotary element is able to be controlled in terms of the rotating speed. 
     A further teaching of the invention provides that the at least one impact element causes a comminution of the loosened ground. 
     A further teaching of the invention provides that the suction box is provided so as to be horizontal, inclined and/or vertical. 
     The object according to the invention is furthermore achieved by a method for producing a substantially vertical borehole in the ground, in particular for producing a shaft, by way of a drill head, in particular by way of a previously described drill head, wherein the drill head is connected to a rotary drive of a drill device, wherein the drill head has a body on which drilling tools are disposed by way of which during drilling the ground at a face of the borehole is loosened and comminuted to a dischargeable size, wherein the loosened and comminuted ground is transported from the face by a discharge device which is connected to a suction unit for suctioning a conveying medium by way of a conveying line, wherein the discharge device has a suction box having an opening region having at least one opening in the region of the drilling tools at the face, said method comprising the following steps:
         introducing an acceleration into loosened ground situated in the region of the opening region, and   acquiring the loosened ground by a conveying medium and discharging said loosened ground by way of the conveying line by the suction unit.       

     A further teaching of the invention provides that the loosened ground is moved through the opening into the suction box as a result of the introduced acceleration. 
     A further teaching of the invention provides that the acquiring takes place in the suction box and/or in the opening region, preferably in front of the opening. 
     A further teaching of the invention provides that the accelerating takes place by dispensing a jet of a transport medium from a nozzle which is directed into the opening region of the suction box as a component part of the discharge device. 
     A further teaching of the invention provides that the moving of the loosened ground takes place by the transport medium. 
     Alternatively or additionally, it is furthermore provided that the accelerating takes place by at least one driven rotary element having at least one impact element disposed thereon, wherein the at least one impact element, by way of a rotating movement, effects the acceleration of the loosened ground by contacting the latter. 
     A further teaching of the invention provides that the moving of the loosened ground takes place by the impact element. 
     As described above, it is advantageous here that the conveying medium and/or the transport medium is a liquid or gaseous medium, preferably water, a bentonite suspension, or air. 
     The terms ground and rock are used synonymously in this application. The same applies in an analogous manner to loosened ground and debris. 
    
    
     
       The invention will be explained in more detail hereunder by means of exemplary embodiments in conjunction with a drawing. In the drawing: 
       In the drawing: 
         FIG.  1    shows a three-dimensional view of the lower side of the drill head of the first embodiment according to the invention; 
         FIG.  2    shows a schematic illustration of a first embodiment of the invention as a fragment of  FIG.  1   ; 
         FIG.  3    shows a schematic, partially sectional plan view of  FIG.  2   ; 
         FIG.  4    shows a schematic illustration of alternative shapes of drill heads according to the invention; 
         FIG.  5    shows a schematic three-dimensional partial view of  FIG.  1   ; 
         FIG.  6    shows a further schematic three-dimensional, partially sectional view of  FIG.  1   ; 
         FIG.  7    shows a further schematic three-dimensional, partially sectional view of  FIG.  1   ; 
         FIG.  8    shows a first diagram pertaining to the discharge according to the invention in conjunction with a drill head as per  FIG.  1   ; 
         FIG.  9    shows a second diagram pertaining to the discharge according to the invention in conjunction with a drill head as per  FIG.  1   ; 
         FIG.  10    shows a schematic lateral view of a first assembly of a suction box in a drill head according to the invention; 
         FIG.  11    shows a schematic lateral view of a second assembly of a suction box in a drill head according to the invention; 
         FIG.  12    shows a partially sectional view of  FIG.  11   ; 
         FIG.  13    shows a schematic lateral view of a treatment in a drill device having a drill head according to the invention; 
         FIG.  14    shows a sectional view pertaining to a second embodiment of the invention; 
         FIG.  15    shows a sectional view of  FIG.  14    rotated by 90°; and 
         FIG.  16    shows drill head profiles as an alternative to  FIG.  14   . 
     
    
    
       FIG.  1    in a three-dimensional illustration shows a drill head  10  according to the invention in a first embodiment. The drill head  10  has a body  11 , drilling tools  12  being disposed on the lower side  13  thereof. The drill head  10 , on the upper side  14  thereof, has a connector (not illustrated) for a drive (not illustrated) of a drill device (not illustrated). The drive not illustrated here is provided directly in the drill device, for example in a shaft drilling machine, for example. Further variants of drives, drill devices and assemblies in a borehole/pole/casing are likewise possible. 
     The lower side  13  here has a planar annular portion  15  (other shapes are possible), drilling tools  12  being provided on the lower side  16  thereof. 
     Proceeding from the annular portion, arms, here eight arms  17  for example, which each have a flank  18  which here in an exemplary manner is planar, extend outward. Clearing tools  19  and consumable elements  40  can be provided on the flanks. Alternatively, the flanks  18  can also be embodied so as to encircle the entire area. 
     A depression  41  which, for example, has a planar area  42  and flanks  43  on which drilling tools  12  are likewise provided is provided in the center of the lower side  30 , for example. 
     The shape of the drill head described here is also referred to as a W drill head. The associated drill profile is illustrated in  FIGS.  8  and  9   . The width of the planar annular portion  15  as well as the angles of the inner and outer flanks  43 ,  18 , as well as the size of the inner area  42 , here are variable and depend on the extraction conditions, as is also illustrated in  FIG.  16   . 
     The drilling tools  12  can be, for example, chisel disks  12   a , peeling chisels  12   b , or roller chisels  12   c , or other alternatives. The selection of the drilling tools  12  takes place as a function of the ground/rock to be loosened in order for the borehole to be established. 
     The connector  45  of the conveying line  31  is illustrated on the upper side  14  of said drill head  10  in  FIG.  1   . 
     Furthermore, the body  11  on the lower side  13  of the W drill head  10  thereof has a suction box  20  on the annular portion  15 . 
     Alternative assemblies of the suction box  20  are shown in  FIG.  4   . In the case of a conical or V-shaped drill head, for example, the suction box  20  according to the invention sits in the maximum penetration of the borehole (on the left in  FIG.  4   ) or extends and is radially provided in a drill head of flat embodiment (on the fight in  FIG.  4   ). A W drill head is illustrated in the center of  FIG.  4   . Apart from horizontal suction boxes as shown in  FIG.  4   , for example, embodiments are also possible in which the suction box  20  is inclined or vertical and the opening  23  thereof is directed downward toward the face  100 , for example. 
     The suction box  20  in a first embodiment, as is shown in  FIG.  2    for example, on the front side  21  thereof has an opening region  22  which has at least one opening  23 . The opening  23  of the first embodiment of the suction box  20  has a classifying element  24  which subdivides the opening  23  into opening portions  23   a . The grain size of the loosened ground/rock that can enter the interior space  25  of the suction box  20  is determined by the classifying element  24 . 
     The interior space  25  is formed by a lid  26  as the upper side and a base  27  as the lower side, said lid  26  and said base  27  as one embodiment here being embodied in a planar manner. Other shapes of lids and bases are likewise possible. The suction box  20  furthermore has lateral walls  28 , the latter here extending from the front side  21  along the shape of the lid and of the base. 
     The shape of the interior space  25  of the suction box  20  is formed as a result of the shape of the lid  26 , of the base  27  and of the lateral walls  28 . A box-type construction can be present here. Alternatively, when the width of the interior space  25  decreases, for example as a result of the curved shape of the lateral walls  28 , a funnel can be present, as a result of which the flow velocity of the suctioned mixture of loosened ground/rock and carrier medium increases as the width decreases. 
     On the rear side of the interior space  25 , an opening  29  is provided on which a connector  30  for a conveying line  31  is provided which during the drilling operation is connected to a suction unit/pump (not illustrated) so as to perform the discharge of the loosened ground/rock, or of the mixture composed of the conveying medium and the loosened ground/rock. 
     Additionally, and not illustrated here, the height of the interior space  25  of the suction box  20 , proceeding from the front side  21  toward the opening  29  on the rear side of the suction box  20 , can also be varied, in particular enlarged, so as to counteract blockages of the interior space  25  by loosened ground/rock. 
     Furthermore, it is likewise possible for the suction box  20 , here illustrated as symmetrical, to be embodied asymmetrically in that the opening  29  is disposed so as to be laterally offset, for example (not illustrated). It can be particularly expedient here, for example in a drill head of a flat embodiment, for the extent of the opening region  22  to be embodied so as to be longer for the opening  29  to be disposed so as to be offset toward the outer circumference of the body  11  so as to increase in a targeted manner the flow velocity in those regions in which more ground/rock is loosened in the rotation of the drill head and enters the interior space  25  of the suction box  20  through the opening  23 . 
     The same is also possible in that the connector  30  of the conveying line  31  (not illustrated) opens into the interior space  25  so as to be inclined into the latter. 
     The opening region  22 , in the region of the opening  23  extending along the front side  21 , can have ground loosening tools and/or ground pick-up tools  33 , for example peeling blades or clearing blades. By providing such tools, it is possible for ground/rock in the region of the front side  21  of the suction box  20  to be loosened and/or picked up in a targeted manner and to be supplied to the opening  23  of the suction box  20 . 
     Additionally or alternatively, baffles (not illustrated) which feed loosened material to the opening region  22  can also be provided on the lower side  13  of the drill head  10 . The feeding can be supported by nozzles such as, for example, purging nozzles  32 . 
       FIG.  2    and  FIG.  3    show a fragment of the drill head  10  according to the invention, having a suction box  20  having an opening  23  and nozzles  34  directed on the latter for dispensing a transport medium  80 , preferably air or a liquid such as, for example, water or a bentonite purge. The conveying medium  90  is suctioned through the conveying line  31  which by way of the opening  29  and the connector  13  is connected to the suction box  20 . Loosened ground  110  is accelerated by the transport medium jet  81  and transported through the opening  23 . In the latter, the loosened ground  110  is acquired by the conveying medium  90 . Loosened ground  110 , the conveying medium  90  and the transport medium  80  here are mixed so as to form a conveying flow  120  which is then discharged by way of the conveying line. Additionally or alternatively, the transport medium jet  81 , as a result of the introduction of acceleration, causes swirling or loosening of the loosened ground  110  from the face  100  in the opening region  22 , respectively, such that the swirling loosened ground is already acquired there by the conveying medium  90  and conjointly with the conveying medium is discharged as a conveying flow  120 . 
       FIG.  5    shows an arm  17  of the W-shaped drill head  10  according to  FIG.  1    having drilling tools  12  as disks  12   a  disposed thereon, and having chisels on the lateral flanks  18  and on the flanks  43  on the lower side  13 . 
     The drilling tools  12  disposed on the arms  17  are able to be replaced from the interior space of the arms  17 . 
       FIG.  6    shows an arm  17  of the W-shaped drill head  10  according to  FIG.  1    having the suction box  20  and the conveying line  31  connected thereto, said suction box  20  and said conveying line  31  being provided within the arm  17 . For the sake of simplicity, no drilling tools  12 ,  12   a  are illustrated in  FIG.  6   . Purging nozzles  32  which are aligned in the direction of the opening  23  of the suction box  20  are provided in the region of the clearing tool  19 . Said purging nozzles  32  dispense a purging jet  130 . The same medium as the transport medium can preferably be used here as the purging medium. The loosened debris  11  is transported by the purging jet  130  into the opening region  22 , or toward the maximum penetration of the borehole  140 , respectively. In this region, the loosened ground  110  is then fed to the opening  23  of the purging box  20  by the nozzles  34 , as is shown in  FIG.  7   . 
     The sequence of loosening the ground and discharging the loosened ground, for example in conjunction with a drill head  10  as per  FIG.  1   , is shown in  FIGS.  8  and  9   . The ground here is loosened by drilling tools  12  and is situated in the region of the respective drilling tools. Purging nozzles  32  are preferably provided in the region of the respective drilling tools  12 . Said purging nozzles  32  dispense a purging jet  130  which purges the loosened ground  110  into the region of the maximum penetration of the borehole  140 . The suction box  20  by way of the opening  23  thereof is moved in this region. The transport medium jet  81 , by way of which the loosened ground is accelerated into the opening  22  and for discharging thus moved into the purging box  20 , and/or in the opening region  22  is suctioned directly by the suction box  20 , is then dispensed by way of the nozzles  34  for dispensing the transport medium jet  81 . 
     The movement/acceleration of the debris into the suction box  20  can be additionally supported by mechanical tools. 
       FIG.  10    shows the introduction of loosened ground into the suction box, the opening  29  thereof, or the connector  30  thereof to the conveying line  31 , respectively, being provided behind the opening region  22 . Shown is a mechanical support when picking up by means of a pick-up tool  33 . The suction box  20  by way of a cylinder  35  can be pivoted about a pivot point  36 . The nozzles  34  are not illustrated here. 
       FIGS.  11  and  12    show the introduction of loosened ground into the suction box  20 , the opening  29  thereof, or the connector  30  thereof to the conveying line  31 , respectively, being provided in front of the opening region  22 . Shown is a mechanical support when picking up by means of a pick-up tool  33 . The suction box  20  by way of a cylinder  35  can be pivoted about a pivot point  36 . The suction box can thus be pivoted in the direction of the arrow A such that the spacing  36  from the face  100  is varied. The assembly of the nozzles  34  is shown in  FIG.  12   . Provided here is a first nozzle  34  which is directed in the direction of the deflection or pick-up tool  33 . Furthermore provided is a second nozzle  34 ′ which is directed in the direction of the opening  29  and the connector  30 . The loosened ground  110  is fed to the conveying medium  120  and discharged conjointly with the latter by the two nozzles  34 ,  34 ′. 
     The conveying flow discharged by way of the conveying line  31  is composed of a combination of solid component parts (loosened ground  110 ) as well as liquid and/or gaseous component parts. The latter are fed to a treatment  200  by way of the conveying line  31  (see  FIG.  13   ). The component parts are separated from one another here, for example by means of at least one cyclone, liquid and/or dust separators. The gaseous component parts (air) are fed again to the drilling region (for example to the shaft already drilled). The liquid component parts are optionally fed to the nozzles  32 ,  34 ,  34 ′ again, or discharged from the drilling region to surface. The solid component parts are by suitable means likewise discharged from the drilling region to the surface. 
     Alternatively or additionally to introducing the acceleration into the loosened ground by means of nozzles and a transport medium, a second embodiment of the invention according to  FIGS.  14    to  16  shows a mechanical introduction of acceleration. Provided to this end is an impact installation  50  which, while provided in the region of the suction box  20  so as to be toward the inside of the drill head  10 , is able to perform an acceleration of the loosened ground  110  in the region of the face  100 . 
     A rotary element  51  on which a plurality of impact elements  52  are provided in an encircling manner is disposed in a housing  57 , said impact elements  52  here preferably being provided so as to be movable by way of a joint  53 . The impact elements  52  move on an impact circle  54  which is provided so as to be concentric about the rotary element  51 . The rotary element  51  is driven by way of a drive (not illustrated). Impact elements  52  impact loosened ground in an impact region  55 , said loosened ground then being introduced in the impact direction  56  into the suction box  20 , or into the opening  23  of the latter, respectively. In the interior space  25  there, and/or in the opening region  22 , the accelerated loosened ground is then acquired by the conveying medium  90  and by way of the conveying flow  120  discharged through the conveying line  31 . 
       FIG.  15    and  FIG.  16    show different assembly widths of the impact installation  50  in conjunction with the flanks  18 ,  43  of the drill head  10 . 
     It is advantageous here for the impact installation  50  to be embodied so as to be as wide as possible (at the bottom of  FIG.  16   ) so as to achieve a better discharge output. 
     It is furthermore advantageous here for the flanks  18 ,  43 , as shown at the top in  FIG.  16   , to be able to be embodied so as to be relatively steep and short in comparison to the installations in  FIG.  15    and at the bottom in  FIG.  16   , such that flank purging, here in the form of an airflow or in the form of clearing elements (not illustrated), can even be dispensed with under certain circumstances. 
     LIST OF REFERENCE SIGNS 
       
     
       
         
           
               
               
             
               
                   
               
             
            
               
                 10 
                 Drill head 
               
               
                 11 
                 Body 
               
               
                 12 
                 Drilling tool 
               
               
                  12a 
                 Chisel disk 
               
               
                  12b 
                 Peeling chisel 
               
               
                  12c 
                 Roller chisel 
               
               
                 13 
                 Lower side 
               
               
                 14 
                 Upper side 
               
               
                 15 
                 Annular portion 
               
               
                 16 
                 Lower side 
               
               
                 17 
                 Arm 
               
               
                 18 
                 Flank 
               
               
                 19 
                 Clearing tool 
               
               
                 20 
                 Suction box 
               
               
                 21 
                 Front side 
               
               
                 22 
                 Opening region 
               
               
                 23 
                 Opening 
               
               
                  23a 
                 Opening portion 
               
               
                 24 
                 Classifying element 
               
               
                 25 
                 Interior space 
               
               
                 26 
                 Lid 
               
               
                 27 
                 Ground 
               
               
                 28 
                 Side wall 
               
               
                 29 
                 Opening 
               
               
                 30 
                 Connector 
               
               
                 31 
                 Conveying line 
               
               
                 32 
                 Purging nozzle 
               
               
                 33 
                 Ground loosening tool/ground pick-up tool 
               
               
                 34/34′ 
                 Nozzle 
               
               
                 35 
                 Cylinder 
               
               
                 36 
                 Pivot point 
               
               
                 37 
                 Spacing 
               
               
                 40 
                 Consumable element 
               
               
                 41 
                 Depression 
               
               
                 42 
                 Area 
               
               
                 43 
                 Flank 
               
               
                 45 
                 Connector 
               
               
                 50 
                 Impact installation 
               
               
                 51 
                 Rotary element 
               
               
                 52 
                 Impact element 
               
               
                 53 
                 Joint 
               
               
                 54 
                 Impact circle 
               
               
                 55 
                 Impact region 
               
               
                 56 
                 Impact direction 
               
               
                 57 
                 Housing 
               
               
                 58 
                 Direction of rotation 
               
               
                 80 
                 Transport medium 
               
               
                 81 
                 Transport medium jet 
               
               
                 90 
                 Conveying medium 
               
               
                 100  
                 Face 
               
               
                 110  
                 Loosened ground 
               
               
                 120  
                 Conveying flow 
               
               
                 130  
                 Purging jet 
               
               
                 140  
                 Maximum penetration of the borehole 
               
               
                 200  
                 Treatment