FR2731024A1 - APPARATUS FOR CREATING TRENCHES IN THE SOIL - Google Patents

Abstract

The invention relates to an apparatus intended for digging trenches in the ground, of the type comprising a frame provided at its lower part with milling drums carrying cutting tools. It has nozzles (6) oriented towards the milling drums (2) to project a pressurized fluid on the cutting tools as they travel over the upper half of the milling drums (2).

Description

The present invention relates to an apparatus for digging

sliced in the ground.

  Known devices known under the brand HYDROFRAISE are already known which consist of a chassis provided at its lower part with two sets each carrying a pair of half-drums located on each side.

  other than a vertical support soul.

  These devices are made to work under mud in soils of different types and in particular in sticky soils, by

clay example.

  However, in these sticky grounds, the efficiency of the apparatus is considerably reduced because the cutting tools have quickly

tendency to clog.

  The present invention aims to provide an apparatus for digging trenches in the ground, which is able to operate both in

  rocky terrain only in sticky terrain with equal efficiency.

  The present invention relates to an apparatus for digging trenches in the ground, of the type comprising a frame provided at its lower part with milling drums carrying cutting tools, characterized in that it further comprises oriented nozzles to the milling drums to project a fluid under pressure on the cutting tools when

  their path on the upper half of the milling drums.

  The present invention also relates to a method for digging trenches in the ground, according to which an apparatus comprising a frame provided at its lower part with milling drums carrying cutting tools is characterized in that, while rotating the milling drums to dig the soil, a fluid under pressure is sprayed onto the cutting tools during

  their path on the upper half of the milling drums.

  According to the invention, fluid under pressure means a liquid or a mixture of liquid and gas, for example consisting of water or water.

water and air.

  This pressurized fluid may advantageously consist of sludge which, in the known manner, is used to fill the trench with

training courses.

  The pressurized fluid is conveyed to the nozzles by a pipe connected to a pump, which can be placed either on the surface of the ground,

  either in the chassis of the device.

  In a preferred embodiment of the invention, the pressure at which the fluid is injected into the nozzles is between 10 and

  500 bar, and preferably between 50 and 150 bar.

  It is understood that the apparatus according to the invention can operate without difficulty in a sticky ground because the cutting tools are permanently cleaned by the jet of fluid under pressure and retain

  thus a good cutting efficiency.

  In a preferred embodiment of the invention, the nozzles are

  located in the vicinity of the suction ports of the winding pump.

  These suction ports, known in the state of the art, are used to evacuate the mud and pieces of ground torn from

cutting tools.

  The fact of placing the nozzles for the projection of the fluid under pressure in the vicinity of these suction orifices has the advantage that the materials detached from the cutting tools by the jet of pressurized fluid

  are directly evacuated through the suction ports of the pump.

  In a preferred variant, these suction orifices are formed in a part housed in the lower part of the frame, between the milling drums and the nozzles for projecting the fluid under pressure according to the invention and are placed at the bottom of this piece, just at

neighborhood cutting tools.

  In order to better understand the invention, will now be described an embodiment given by way of non-limiting example and shown in the accompanying drawing in which: - Figure 1 is an elevational view and partly in section; according to IV-IV of the lower part of an apparatus according to one embodiment of the invention, - Figure 2 is a right view of Figure 1, the milling drums on the right are not shown, - Figure 3 is a sectional view IV-- IV and on a larger scale of the part 4, and

  FIG. 4 is a right view of FIG.

  The apparatus described, the lower part of which is shown in FIG. 1, comprises a frame 1 to which two pairs of

  milling drums 2 supported by a core 3.

  The milling drums 2 are trained conventionally

  for example by a hydraulic motor, not shown, mounted in the frame.

  Cutting tools, not shown, are attached to the periphery of each milling drum 2 to dig the soil during the

descent of the device.

  The drums are trained in the direction of the arrows so that they go back between them, in the center of the chassis, the debris or cuttings

  from the soil they break up.

  A suction part 4, of triangular lower section, is placed between the two pairs of drums, at the bottom of the drum.

chassis 1.

  As seen in Figure 2, this suction part 4 extends over the entire width of the device and has four orifices 5 through which the drilling mud and soil debris are sucked, when

  operation of the apparatus, by a winding pump not shown.

  These orifices 5 thus make it possible to evacuate the ripped materials

  ground by cutting tools during drilling.

  In accordance with the invention, nozzles 6 are directed to the milling drums 2 for throwing pressurized fluid onto the cutting tools as they travel over the upper half of the drums.

milling 2.

  These nozzles 6 are screwed into the lower edge 7 of the suction part 4, this edge 7 constituting the top of the lower section.

  triangular of said suction part.

  As can be seen in FIGS. 2 and 4, this edge 7 comprises, on each of its faces, a row of orifices 8 directed towards the pair of

  milling drums 2 corresponding.

  These orifices 8 are each intended to receive a nozzle 6.

  Each nozzle 6 is fed by a central channel 9 itself connected to a vertical duct 10 connected to a pressure pipe (not shown). During the operation of the device, sludge is sent under

  pressure, for example of the order of 100 bar, in the central channel 9.

  Jets of pressurized sludge are thus projected on the cutting tools which run past the nozzles 6 during the rotation of the milling drums and which are thus cleared of the parts of sticky ground which

could clog them.

  The mud and pieces of ground torn off by the cutting tools are then removed by the winding pump through the holes

  5, as shown by the arrows in FIG.

  - 4 - It is understood that the embodiment just described is not limiting in nature and that it will receive all

  desirable modifications without departing from the scope of the invention.

  In particular, it is clear that another fluid that mud can be thrown under pressure on tools, such as water

  or a mixture of liquid and gas such as water and air.

  In addition, it goes without saying that the nozzles for projecting the pressurized fluid can be arranged differently from what has been previously described, these nozzles, however, sending the fluid to the tools located

  0 on the upper half of the drums.

Claims (7)

  1. Apparatus for digging trenches in the ground, of the type comprising a frame provided at its lower part with milling drums carrying cutting tools, characterized in that it comprises nozzles (6) oriented towards the drums of milling (2) for throwing a fluid under pressure on the cutting tools as they travel on the   upper half of the milling drums (2).   2. Apparatus according to claim 1, characterized in that the nozzles (6) are located in the vicinity of the suction ports (5) of the winding pump.   3. Apparatus according to claim 2, wherein the suction ports (5) are formed in a part (4) housed in the lower part of the frame (1), between the milling drums (2), characterized in that that the nozzles (6) for projecting the fluid under pressure are   placed at the bottom of this piece (4).   4. A method for digging trenches in the ground using an apparatus comprising a frame provided at its lower part with milling drums carrying cutting tools, characterized in that, while driving in rotation the milling drums (2), a pressurized fluid is sprayed onto the cutting tools as they travel on the   upper half of the milling drums (2).   5. Method according to claim 4, characterized in that the fluid used under pressure is the sludge which is used for   fill the trench during training.   6. Process according to claim 4, characterized in that a mixture of liquid and gas is used as pressurized fluid.   as for example a mixture of water and air.   7. Process according to Claim 4, characterized in that the fluid under pressure is subjected to a pressure of between 10 ° C.   and 500 bar, and preferably between 50 and 150 bar.