JP4991480B2 - Excavation and stirring tool for ground improvement equipment - Google Patents

Description

  The present invention relates to a drilling / stirring tool for a ground improvement device.

  Conventionally, as one form of the ground improvement device, there is one in which ground improvement is performed by discharging the improvement material while excavating and stirring the ground and kneading the improvement material and the excavated soil (for example, patents) Reference 1).

That is, in this ground improvement device, an inner / outer stirring blade formed in an arc shape is attached to the lower end portion of the excavation / stirring shaft of the inner / outer double structure extending in the vertical direction, and the inner stirring blade is attached to the inner shaft. At the same time, the outer agitator blades are attached to the outer shaft, and the inner and outer shafts are rotated in the opposite directions, so that the excavated soil and the improved material are mixed by relative agitation in which the inner and outer agitator blades are rotated in the opposite directions. To be able to.
JP-A-3-63312

  However, in the ground improvement device described above, the excavation / stirring shaft has an inner / outer double shaft structure in order to reversely rotate the inner / outer stirring blades mutually, and the inner / outer shaft is connected to the drive motor via a counter rotating gear mechanism. The upper end of the outer double shaft is interlocked to make it larger. Therefore, the manufacturing cost of such a ground improvement device is expensive and the ground improvement construction cost is increasing.

  Moreover, in a confined area, a large-sized ground improvement device cannot be carried in, and therefore development of a small and inexpensive ground improvement device has been desired.

In the present invention, excavation and agitation that extends in the vertical direction is performed in the ground improvement device that discharges the improved material while excavating and agitating the ground and kneads the improved material and the excavated soil. A stirrer blade and a kneading blade are provided on the outer peripheral surface of the shaft, and the stirrer blade is formed in an arc shape with its middle part bulging outward, and its base end is fixed to the outer peripheral surface of the excavation / stir shaft. On the other hand, the tip is loosely fitted on the outer peripheral surface of the boss portion that is rotatably fitted around the peripheral surface of the excavation / stirring shaft, and the kneading action blade is arranged in the radial direction of the boss portion and the boss portion. A plurality of kneading action bodies formed by stretching are provided, and the tip of the kneading action body arranged outside the stirring blade is formed to extend to an outer position than the bulging end of the stirring blade. On the other hand, the tip of the kneading action body arranged inward of the stirring blade is swollen by the stirring blade. Formed by distracted to the end near the position, the attachment of the diffuser vanes body radially extending portion forming the bottom of the stirring blade, diffuser vanes body facing state a pair of diffuser vanes piece which extends in the direction of rotation of the stirring blade The ground is characterized in that the facing distance between the two diffusion blades is gradually widened from the downstream side to the upstream side in the rotation direction so that the excavated soil passing between the two diffusion blade pieces is diffused. An improved apparatus for drilling and stirring is provided.

  Here, the “arc shape” which is the shape of the stirring blade body is not limited to a substantially arc shape having no corner portion (a shape according to the present embodiment), but is a substantially triangular arc shape having one corner portion and two corner portions. In addition, a substantially quadrangular arc shape having two corners, a substantially polygonal arc shape having three or more corners, and the like are also included.

  Further, the following configuration is also characterized.

  (1) The kneading action body arranged inward of the stirring blade is formed in an arc shape with the middle part bulging outward.

  (2) An inner stirring blade is disposed inside the kneading action body formed in an arc shape by expanding the middle part outward, and the inner stirring blade has a proximal end on the outer peripheral surface of the excavation / stirring shaft. It was fixed.

  (3) A guide rotating body that rolls along the unexcavated ground is attached to the tip of the kneading action body arranged outside the stirring blade.

  (4) The guide rotator should be able to advance and retract in the extending direction of the kneading operation body and be elastically biased in the advancing direction.

  (5) The side surface of the kneading action body arranged outside the stirring blade is an inclined surface inclined with respect to the vertical direction, and the kneading action body rolls along the unexcavated ground of the guide rotating body. -Rotating around the excavation / stirring shaft in conjunction with the movement.

  (6) At the lower end of the excavating / stirring shaft extending in the vertical direction, a stirring blade formed in an arc shape with the middle portion bulging outward is attached, and at the radially extending portion forming the lower portion of the stirring blade A plurality of excavating blades were detachably mounted via a plurality of mounting bodies, respectively.

(1) The excavation / stirring tool according to the first aspect of the present invention is to improve the ground by discharging the improvement material while excavating / stirring the ground and kneading the improvement material and the excavation soil. In the improved ground improvement device, a stirring blade and a kneading action blade are provided on the outer peripheral surface of the excavating and stirring shaft extending in the vertical direction, and the stirring blade is formed in an arc shape by bulging the middle part outward. The base end is fixed to the outer peripheral surface of the excavation / stirring shaft, while the tip is loosely fitted on the outer peripheral surface of the boss portion rotatably fitted around the peripheral surface of the excavation / stirring shaft, and the kneading action blade Comprises the boss part and a plurality of kneading action bodies formed by extending the boss part in the radial direction, and the tip of the kneading action body arranged outside the stirring blades While extending to the outer position than the bulging end of The tip of the interrupt working body is formed by distracted to bulge end vicinity of the stirring blade is attached to diffuser vanes body radially extending portion forming the bottom of the stirring blade, diffuser vanes body, stirring blade A pair of diffusion blades extending in the direction of rotation of the diffusion blades are arranged in an opposing state, and the facing distance between the two diffusion blades is upstream from the downstream side in the rotation direction so that the excavated soil passing between the two diffusion blade pieces is diffused. It is gradually formed wider on the side .

  Thus, the kneading action body arranged outside the stirring blade among the plurality of kneading action bodies is positioned on the unexcavated ground where the tip is not excavated, and the tip and the unexcavated ground are Friction resistance is generated between them, and it moves only in the excavation direction, so that it does not rotate. At this time, it is preferable to use a single kneading working blade in order to make the frictional resistance in the digging direction as small as possible and to secure a detent function.

  The above-mentioned kneading action body and the other kneading action bodies integrated with each other through the boss portion are disposed inside the stirring blade formed in an arc shape, and the tip is the bulging end of the stirring blade body. By forming it by extending it to a nearby position, it is in the agitating blade body that is rotationally driven and does not rotate.

  As a result, excavated soil and improved soil are agitated inside the agitating blade and agitated inside the agitating blade by the agitating blade that is driven to rotate in one direction around the excavating and agitating shaft. The soil and the improved soil are kneaded and stirred by the kneading agent, and good kneading properties similar to conventional relative stirring are ensured.

Thus, the excavation / stirring tool according to the first aspect of the present invention ensures good kneadability between the excavated soil and the improved soil simply by rotating the stirring blade attached to the single-shaft excavation / stirring shaft. Therefore, it is possible to reduce the size of the ground improvement device equipped with the excavation / stirring tool, to easily perform the ground improvement work in a narrow area, and to reduce the manufacturing cost of the ground improvement device. The ground improvement construction cost can be reduced.
In addition, by moving the diffusion blades so as to form a circular orbit around the excavation / stirring shaft on substantially the same horizontal plane, the mutual distance gradually increases from the downstream side to the upstream side in the rotation direction. When excavated soil passes between a pair of diffusing blade pieces, the bond between the soils is dispersed, and an improvement material such as cement slurry is mixed in the gap to promote fluidization as improved soil and kneadability. Can be further improved.

  (2) In the present invention as set forth in claim 2, the kneading action body disposed inside the stirring blade is formed in an arc shape with its midway portion bulging outward.

  Thus, the kneading action body formed in an arc shape along the inner side of the stirring blade formed in an arc shape can be arranged. As a result, the arc-shaped stirring blades located on the outer side and the arc-shaped kneading action members located on the inner side cooperate to perform a kneading operation that approximates relative stirring, so that the excavated soil and the improved material are kneaded firmly. Can do.

  (3) In the present invention according to claim 3, the inner stirring blade is disposed inside the kneading action body formed in an arc shape by expanding the middle portion outward, and the inner stirring blade is excavated and The base end is fixed to the outer peripheral surface of the stirring shaft.

  Thus, the kneading action body formed in the arc shape can be disposed between the outer stirring blade body formed in the arc shape and the inner stirring blade body. As a result, the agitation efficiency can be improved by the agitating blades that are rotationally driven located on the inner and outer sides, and kneading and agitation by the kneading action body formed in an arc shape between the two can be steadily achieved. Can do.

  At this time, the shape of the inner stirring blade can be formed by extending in the radial direction of the excavation / stirring shaft, but can also be formed in an arc shape along the outer stirring blade body or the kneading action body.

  (4) In this invention of Claim 4, the guide rotary body which rolls along an unexcavated ground is attached to the front-end | tip of the kneading action body arrange | positioned outside the stirring blade.

  In this way, since the guide rotator rolls along the unexcavated ground, the frictional resistance received from the unexcavated ground can be greatly reduced, and there is a mixture of gravel, boulders, glass, etc. The excavation efficiency can be improved even on ground that has a high N value.

  (5) In the present invention described in claim 5, the guide rotator is movable forward and backward in the extending direction of the kneading action body and elastically biased in the advancing direction.

  In this way, in particular, even in the ground where gravels, boulders, galley, etc. are mixed, it is possible to roll the rotator while moving over the gravels, boulders, galley, etc. by appropriately moving the guide rotating body forward and backward. This can be further improved.

  (6) In the present invention described in claim 6, the side surface of the kneading action body disposed outside the stirring blade is an inclined surface inclined with respect to the vertical direction, and the kneading action body is a guide rotor. It is designed to rotate around the excavation and agitation shaft in conjunction with rolling and moving along the unexcavated ground.

  In this way, the ground can be improved efficiently by kneading the excavated soil and the improving material by the agitating blade that rotates and the kneading blade that rotates.

  At this time, good kneadability is ensured by setting the stirring blades to be rotationally driven and the kneading action blades to be rotationally operated to be different. For example, by setting the rotational speed of the agitating blade to be rotationally driven appropriately larger or smaller than the kneading working blade whose rotational speed is determined by the excavation speed of the excavating / stirring shaft and the soil quality of the excavated ground, Good kneadability can be secured.

  In particular, when the side surface of the kneading action body arranged outside the stirring blade is an inclined surface inclined with respect to the vertical direction so that the stirring blade and the kneading action blade rotate in opposite directions to each other In this case, since the outer stirring blade and the kneading action blade cooperate to perform a kneading operation similar to relative stirring, the excavated soil and the improved material can be firmly mixed.

  (7) In the present invention according to claim 7, the lower end of the excavation / stirring shaft extending in the vertical direction is attached with a stirring blade formed in an arc shape by expanding the middle portion outward, A plurality of excavating blades are detachably attached to the radially extending portions forming the lower portion via a plurality of attachment bodies, respectively.

  In this way, the radially extending portion that forms the lower part of the stirring blade can be used as a drilling blade body for excavating the ground. At this time, since the plurality of excavating blades are detachably mounted through the plurality of mounting bodies, it is possible to replace each damaged excavating blade via the mounting body, and the labor and cost of the replacement work are reduced. Can be reduced.

  Hereinafter, an embodiment of an excavation / stirring tool of a ground improvement device according to the present invention will be described with reference to the drawings.

[First Embodiment]
1A is a side view of the digging / stirring tool A as the first embodiment, and FIG. 1B is a cross-sectional plan view of the digging / stirring tool A. FIG.

  Here, the ground improvement device (not shown) includes an excavation / stirring tool A and a lifting / lowering drive support unit (such as a base machine) that supports the excavation / stirring tool A so that it can be moved up and down and forward / reversely driven. And an improvement material supply section (not shown) for supplying the improvement material to the excavation / stirring tool A, and discharging the improvement material while excavating / stirring the ground. The ground is improved by kneading the excavated soil. The improvement material is not limited to solidified material such as cement milk, but is a chemical agent or agent that neutralizes, extinguishes, or purifies the ground or groundwater contaminated with harmful substances to make it pollution-free, for example, first chloride Iron or ferric chloride can be used.

  As shown in FIG. 1, the excavation / stirring tool A is provided with a stirring blade 2 and a kneading action blade 3 at the lower end of the excavation / stirring shaft 1. The excavation / stirring shaft 1 is formed in a hollow tubular shape extending in the vertical direction, and a stirring blade 2 and a kneading working blade 3 are attached to the lower portion of the outer peripheral surface, while the space inside the tubular portion is used as an improvement material supply path. An improvement material discharge section (not shown) is provided at the lower end, and the improvement material is supplied and discharged from the above-described improvement material supply section → improvement material supply path → improvement material discharge section.

  The agitating blade 2 is formed in an arc shape by bulging the midway part 2c outward, and its base end 2a is fixed to the lower end portion of the outer peripheral surface of the excavating / stirring shaft 1, while the excavating / stirring shaft 1 The tip 2b is loosely fitted to the outer peripheral surface of the boss portion 4 that is rotatably fitted around the peripheral surface. A plurality (two in the present embodiment) of the stirring blades 2 are provided on the excavation / stirring shaft 1 so as to be arranged at symmetrical positions on the axis. In addition, a discharge part (not shown) for discharging the improved material or air toward the middle part 2c of the stirring blade 2 is provided in the excavation / stirring shaft 1 located immediately above the base end 2a of the stirring blade 2. Can do. In this way, by discharging the improving material or air from the discharge section, the soil can be dispersed and diffused with these discharge pressures. As a result, it is possible to improve the stirring and kneading properties between the improving material and the soil.

  A plurality of excavating blades 5 are detachably attached to the radially extending portion 2 d forming the lower part of the stirring blade 2 through a plurality of attachment bodies 6 to form excavation blades 7. As shown in FIGS. 2 and 3, the excavating blade 7 is formed by integrally forming two excavating blades 5 on a single mounting body 6 with an interval in the extending direction of the radially extending portion 2d. A fitting recess 6a formed in each mounting body 6 is fitted to the front surface side (downstream in the excavation rotation direction) of the direction extending portion 2d, and a connecting bolt 8 is interposed in the middle of the radially extending portion 2d. Thus, the connecting portions 6b formed on each mounting body 6 are connected. Reference numeral 9 denotes an integral connecting piece that integrally connects a plurality (three in the present embodiment) of the mounting bodies 6.

  In this way, when the excavation blade 5 is worn or damaged, it can be replaced for each mounting body 6 formed integrally with the excavated blade 5 that is worn or damaged.

  FIG. 4 shows a modified example of the mounting body 6, in which the adjacent end surface 6 c is an inclined surface inclined with respect to the extending direction of the radially extending portion 2 d and is attached to the ground excavation holder via the excavating blade 5. The shearing force received by the body 6 is dispersed so that the load acting on the mounting body 6 can be reduced.

  As shown in FIG. 1, the kneading action blade 3 includes the boss part 4 and a plurality of kneading action bodies 10 formed by extending the boss part 4 in the radial direction (two sets in this embodiment). , 11.

  And the boss | hub part 4 is formed in a cylinder shape, it fits rotatably around the outer peripheral surface of the digging and stirring shaft 1, and the front-end | tip 2b of the stirring blade 2 is loosely fitted in the middle part of the outer peripheral surface. Reference numerals 12 and 13 denote stopper bodies that restrict the boss portion 4 from sliding in the axial direction of the excavation / stirring shaft 1.

  Further, the kneading operation body 10 has a base end attached to the upper peripheral surface of the boss portion 4 positioned just above the tip 2b, which is outside the stirring blade 2, and linearly extends in the radial direction of the boss portion 4. The guide rotating body 15 formed in a disk shape is rolled along the unexcavated ground G (see FIGS. 6 and 7) via the rotating support shaft 14 at the distal end of the kneading working body 10. The kneading action body 10 is attached freely and freely movable in the extending direction. A pressure spring 16 serving as an elastic biasing member is interposed between the rotation support shaft 14 and the kneading operation body 10 to elastically move the guide rotation body 15 in the advance direction (direction in which the unexcavated ground G is pressed). Energized.

  In addition, the outer peripheral end of the guide rotator 15, which is the tip of the kneading action body 10, is disposed at an outer position than the bulging end of the stirring blade 2, so that the guide rotator 15 is always unexcavated. It rolls along the ground G (see FIGS. 6 and 7). Furthermore, as shown in the end view of FIG. 5, both side surfaces 10 a and 10 a of the kneading operation body 10 are inclined so as to incline forward, backward and rearward with respect to the vertical direction (with the downstream side in the excavation rotation direction as the front). There is a surface. A plurality of kneading action bodies 10 (two in this embodiment) are provided on the excavation / stirring shaft 1 at positions symmetrical with respect to the axis thereof.

  The kneading action body 11 has a base end attached to the lower part of the peripheral surface of the boss portion 4 that is the inner side of the stirring blade 2, and the tip is straight in the radial direction of the boss portion 4 to a position near the bulging end of the stirring blade 2. It is formed by extending it. A plurality (two in this embodiment) of the kneading action bodies 11 are provided on the excavation / stirring shaft 1 at positions symmetrical with respect to the axis thereof.

  As shown in FIG. 6, when the excavation / stirring tool A is moved downward while rotating the excavation / stirring shaft 1 clockwise a in plan view, the guide rotator 15 moves along the unexcavated ground G. The kneading action body 10 rotates in a counterclockwise direction b in plan view around the excavating / stirring shaft 1 in conjunction with the rolling / moving movement. P1 is an excavation direction, and K1 is a rolling / moving locus of the guide rotator 15.

  Therefore, the agitating blade 2 connected to the excavation / stirring shaft 1 and driven to rotate, and the kneading action blade 3 rotated as described above rotate in the opposite directions, and the excavated soil and Relative stir the improver. At this time, the drilling soil agitated by the stirring blade 2 and the kneaded soil of the improved material are kneaded, and the kneading action bodies 10 and 11 of the working blade 3 are kneaded densely, so that the kneadability can be improved. .

  Further, as shown in FIG. 7, when the excavation / stirring tool A is pulled upward while rotating the excavation / stirring shaft 1 counterclockwise b in plan view, the guide rotator 15 rolls along the unexcavated ground G. The kneading operation body 10 is moved in conjunction with the excavating / stirring shaft 1 and rotated clockwise a in plan view. P2 is a drawing direction, and K2 is a rolling / moving locus of the guide rotator 15.

  Therefore, the stirring blade 2 that is rotationally driven in conjunction with the excavation / stirring shaft 1 and the kneading action blade 3 that is rotationally operated as described above rotate in opposite directions to improve the excavated soil and the improvement. Relatively stir the material. At this time, the kneading action bodies 10 and 11 of the working blade 3 knead the excavated soil stirred by the stirring blade 2 and the kneaded soil of the improved material, and the excavating / stirring tool A is pulled upward. The kneadability can also be improved.

  In addition, by providing the above-mentioned improvement material discharge part (not shown) in the part of the excavation / stirring shaft 1 located directly below the kneading operation body 11, the improvement material is discharged from the improvement material discharge part. The improved material and the excavated soil can be kneaded densely by the stirring blade 2 and the kneading action body 11 that are relatively stirred.

  Further, in the present embodiment, the setting of the both side surfaces 10a, 10a of the kneading action body 10 (formation of inclined surfaces) is performed so that the kneading action blade 3 is opposite to the stirring blade 2 in the rotation direction. Although stirring is performed, the kneading action blade 3 can be prevented from rotating, or can be rotated at a different rotational speed in the same direction as the stirring blade 2.

[Second Embodiment]
FIG. 8A is a side view of the excavation / stirring tool A as the second embodiment, and FIG. 8B is a sectional plan view of the excavation / stirring tool A.

  The excavation / stirring tool A as the second embodiment has the same basic structure as that of the excavation / stirring tool A as the first embodiment described above, but the excavation / stirring shaft starts from the middle part 2c of the stirring blade 2 The difference is that the stirring blade pieces 2e and 2f extending in parallel with each other toward 1 are disposed directly above and below the kneading action body 11.

  In this way, the horizontal shearing of the kneaded soil by the stirring blade pieces 2e and 2f and the kneading action body 11 that are rotated in opposite directions and relatively stirred is increased, thereby improving the kneadability.

[Third Embodiment]
9A is a side view of the excavation / stirring tool A as the third embodiment, and FIG. 9B is a cross-sectional plan view of the excavation / stirring tool A. FIG.

  The excavation / stirring tool A as the third embodiment has the same basic structure as that of the excavation / stirring tool A as the first embodiment described above. The difference is that the wing 2 and the kneading agent 11 are added.

  Thus, the kneadability is improved by the additional stirring blade 2 and the kneading action body 11.

[Fourth Embodiment]
FIG. 10A is a side view of the excavation / stirring tool A as the fourth embodiment, and FIG. 10B is a sectional plan view of the excavation / stirring tool A.

  The excavation / stirring tool A as the fourth embodiment has the same basic structure as that of the excavation / stirring tool A as the first embodiment described above. 11 in that an inner stirring blade 17 extending in the radial direction from the outer peripheral surface of the excavation / stirring shaft 1 is provided.

  Thus, the kneadability is improved by increasing the number of inner stirring blades 17 that are rotationally driven.

[Fifth Embodiment]
FIG. 11A is a side view of the digging / stirring tool A as the fifth embodiment, and FIG. 11B is a cross-sectional plan view of the digging / stirring tool A.

  The excavation / stirring tool A as the fifth embodiment has the same basic structure as the excavation / stirring tool A as the first embodiment described above, but the kneading action disposed inside the stirring blade 2. The body 11 is formed in an arc shape with its middle part bulging outward, and its tip is loosely fitted to the outer peripheral surface of the excavation / stirring shaft 1. And the inner stirring blade 17 is different in that the base end is fixed to the outer peripheral surface of the excavation / stirring shaft 1.

  In this way, the stirring blades 2 and the inner stirring blades 17 are disposed at the inner and outer positions of the kneading action body 11 that is formed in an arc shape by bulging the midway portion outward, so that they are relatively stirred. Therefore, kneadability can be further improved.

  Here, in the fifth embodiment, the inner stirring blade 17 is formed in a straight shape by extending in the radial direction of the excavation / stirring shaft 1, but the inner stirring blade 17 is also a stirring blade 2 or a kneading agent. As in the case of 11, the kneadability can be further improved by forming the middle part in an arc shape that bulges outward.

[Sixth Embodiment]
12A is a side view of the excavation / stirring tool A as the sixth embodiment, and FIG. 12B is a cross-sectional plan view of the excavation / stirring tool A. FIG.

  The excavation / stirring tool A as the sixth embodiment has the same basic structure as the excavation / stirring tool A as the fifth embodiment described above, but the agitating / stirring tool A is agitated immediately above the kneading action body 10. The difference is that the blade 2, the kneading agent 11, and the inner stirring blade 17 are added.

  Thus, the kneadability is improved by the additional stirring blade 2, the kneading action body 11, and the inner stirring blade 17.

[Seventh Embodiment]
FIG. 13A is a side view of the excavation / stirring tool A as the seventh embodiment, and FIG. 13B is a sectional plan view of the excavation / stirring tool A.

  The excavation / stirring tool A as the seventh embodiment is provided with a drilling blade 7 at the lower end of the excavation / stirring shaft 1, and the excavation blade 7 extends in the radial direction of the excavation / stirring shaft 1. The blade bodies 18 and 18 are arranged at an axially symmetric position of the excavation / stirring shaft 1 and integrally formed, and a plurality of excavating blades 19 are formed in contact with both the stirring blade bodies 18 and 18. Then, the kneading action blade 3 is disposed immediately above the excavation blade 7, and the stirring blade 2 is disposed immediately above the kneading action blade 3. An improved material discharge section (not shown) can be provided at the center of the lower end of the excavation blade 7 or the excavation / stirring shaft 1 located inside the stirring blade 2.

  In this way, by arranging the kneading action body 10 that rotates in the same direction at different rotational speeds or rotation speeds between the excavating blade 7 and the stirring blade 2 that rotate in the same direction, The kneading of the excavated soil can be made steady.

[Eighth Embodiment]
14A is a side view of the excavation / stirring tool A as the eighth embodiment, and FIG. 14B is a cross-sectional plan view of the excavation / stirring tool A.

  The excavation / stirring tool A as the eighth embodiment has the same basic structure as the excavation / stirring tool A as the seventh embodiment described above, but the agitating blade 2 is positioned just above the excavation blade 7. The kneading action blade 3 is disposed immediately above the stirring blade 2 and the stirring blade 2 is provided with stirring blade pieces 2g and 2h extending in the vertical direction or the left and right direction. 11 is provided with a kneading action piece 11a extending in the vertical direction, and the kneading action piece 11a is disposed between the stirring blade pieces 2g and 2g extending in the vertical direction.

  In this way, the stirring blade pieces 2g and 2h and the kneading action piece 11a relatively agitate the excavated soil and the improving material, thereby improving the kneading properties.

[Ninth Embodiment]
FIG. 15A is a side view of the excavation / stirring tool A as the ninth embodiment, and FIG. 15B is a cross-sectional plan view of the excavation / stirring tool A.

  The excavation / stirring tool A as the ninth embodiment has the same basic structure as the excavation / stirring tool A as the seventh embodiment described above, but the stirring blade 2 and the kneading working blade 3 are vertically aligned. The difference is that it is symmetrically expanded.

  In this way, kneadability is improved.

[Tenth embodiment]
16A is a side view of the excavation / stirring tool A as the tenth embodiment, and FIG. 16B is a cross-sectional plan view of the excavation / stirring tool A.

  The excavation / stirring tool A as the tenth embodiment has the same basic structure as the excavation / stirring tool A as the seventh embodiment described above, but the kneading action body 10 is located directly above the stirring blade 2. It is different in that the radially extending portion 2 d that forms the lower part of the stirring blade 2 is disposed at a position immediately above the excavation blade 7. Furthermore, the difference is that a diffusion blade 20 is provided in the radially extending portion 2d.

  That is, as shown in FIGS. 16 and 17, three stirring blades 2 are arranged on the outer peripheral surface of the excavation / stirring shaft 1 at equal intervals in the circumferential direction, and the radially extending portions of the respective stirring blades 2 are arranged. The diffusion blade bodies 20 are suspended from the lower surface of 2d, and each diffusion blade body 20 is disposed at a position directly above the excavation blade 7.

  Then, as shown in FIG. 17 which is a bottom explanatory view, the diffusion blade body 20 has a pair of plate-like diffusion blade pieces 21 and 21 extending in the rotational direction on the lower surface of the radially extending portion 2d, and the mutual distance between them. They are formed in a “C” shape as viewed from the bottom so that the width gradually increases from the downstream side in the rotational direction to the upstream side. In this embodiment, the diffusion blade pieces 21 and 21 are formed in a flat plate shape. However, the side surface shape of the diffusion blade pieces 21 and 21 is a shape that can smoothly diffuse and guide the excavated soil. If it is, it will not be restricted to this, It can also form in the curved arc shape.

  In addition, with the diffusion blade body 20 disposed on the outermost side of the radially extending portion 2d as a reference, the diffusion blade body 20 is placed on the excavation / stirring shaft 1 side in the radial extension portion 2d adjacent to the downstream side in the rotational direction. Diffusion blade body 20 is further biased toward the excavation / stirring shaft 1 side in the radially extending portion 2d adjacent to the downstream side in the rotation direction, and is used as a reference diffusion blade body. The diffusion blade piece 21 outside the diffusion blade body 20 adjacent to the downstream side in the rotation direction is located in a rotation locus formed on substantially the same horizontal plane by the diffusion blade pieces 21 and 21 on the inner and outer sides, and the diffusion is the same. The diffusion blade piece 21 outside the diffusion blade body 20 adjacent to the downstream side in the rotation direction is positioned in the rotation locus formed on substantially the same horizontal plane by the diffusion blade pieces 21 and 21 inside and outside the blade body 20. I have to.

  In this way, by moving the three sets of diffusion blades 20, 20, 20 in a position directly above the excavation blade 7 so as to draw a circular orbit around the excavation / stirring shaft 1 on substantially the same horizontal plane. As shown in FIG. 18, excavation is made between a pair of diffusion blade pieces 21, 21 arranged in a letter “C” in the bottom view so that the mutual space gradually increases from the downstream side to the upstream side in the rotation direction. When the soil passes, the bonds between the soils g are dispersed, and an improving material such as cement slurry is mixed in the gaps to promote fluidization as the improved soil, thereby further improving the kneadability. d1 is an internal diffusion direction between the diffusion blade pieces 21 and 21. Further, the outer side surfaces of the diffusion wing pieces 21, 21 arranged in a letter “C” shape in a bottom view function like the side of the ship, and along the rotation trajectory of the diffusion wing body 20, the soil is Like the wake, it is diffused in the external diffusion direction d2, and mixing with the cement slurry is promoted.

  Here, the improvement material is discharged from the improvement material discharge section (not shown) in the vicinity of the dispersed and fluidized excavation soil, so that the improvement blade and the excavation soil are relatively agitated and kneaded. It becomes easy to knead densely with the body 11.

  In addition, the diffusion blade body 20 is disposed so as to be displaced in the radial direction on each of the three stirring blades 2 arranged at equal intervals in the circumferential direction of the excavation / stirring shaft 1. A substantially equal load can be applied to each stirring blade 2 via 20. As a result, it is possible to avoid an overload from acting on some of the stirring blades 2 and to prevent a problem that some of the stirring blades 2 are damaged in a shorter time than usual due to the overload. it can. Therefore, kneadability can be improved, the life of each stirring blade 2 can be made uniform, and as a result, the life of each stirring blade 2 can be extended.

  FIG. 19 shows a first modification of the above-described tenth embodiment, in which a vertical shunting blade piece 22 is interposed between the diffusion blade pieces 21 and 21, and as described above, the diffusion blade pieces 21, In addition to the diversion / spreading of the soil in the left-right direction by 21, the diversion / spreading of the soil in the vertical direction is performed by the vertical diversion formation blade piece 22. d3 is an upper diffusion direction, and d4 is a lower diffusion direction.

  FIG. 20 shows a second modification of the above-described tenth embodiment. Each of the diffusion blade pieces 21 and 21 is provided with vertical diversion-forming blade pieces 22 and 22 projecting in the left and right sides, respectively. In addition to the shunting / diffusion of soil in the left-right direction by the wing pieces 21, 21, the vertical shunting / spreading is performed by the up / down direction shunt forming wing pieces 22, 22.

  In the tenth embodiment and the first and second modification examples described above, the case where the diffusion blade body 20 is provided in the radially extending portion 2d has been described, but the diffusion blade body 20 is provided on the excavation blade 7. And the diffusion blade body 20 can be disposed between the radially extending portion 2d and the excavation blade 7, and in this case, the same effect can be obtained.

(A) is a side view of the excavation / stirring tool as the first embodiment, and (b) is a sectional plan view of the excavation / stirring tool. The bottom view of a drilling wing. The side view of the excavation blade. The bottom view of the excavation blade which shows the example of a change of a mounting body. The end view of a kneading agent. Explanatory drawing. Drawing explanatory drawing. (A) is a side view of a digging / stirring tool as a second embodiment, and (b) is a sectional plan view of the digging / stirring tool. (A) is a side view of a digging / stirring tool as a third embodiment, and (b) is a sectional plan view of the digging / stirring tool. (A) is a side view of a digging / stirring tool as a fourth embodiment, and (b) is a sectional plan view of the digging / stirring tool. (A) is a side view of a digging / stirring tool as a fifth embodiment, and (b) is a sectional plan view of the digging / stirring tool. (A) is a side view of a digging / stirring tool as a sixth embodiment, and (b) is a sectional plan view of the digging / stirring tool. (A) is a side view of a digging / stirring tool as a seventh embodiment, and (b) is a sectional plan view of the digging / stirring tool. (A) is a side view of a digging / stirring tool as an eighth embodiment, and (b) is a sectional plan view of the digging / stirring tool. (A) is a side view of a digging / stirring tool as a ninth embodiment, and (b) is a sectional plan view of the digging / stirring tool. (A) is a side view of a digging / stirring tool as a tenth embodiment, and (b) is a sectional plan view of the digging / stirring tool. Explanatory drawing of a bottom face of a diffusion wing body. The soil dispersion | distribution explanatory drawing by a diffusion wing body. (A) is front expansion explanatory drawing of the diffusion wing | blade body as a 1st modification of 10th Embodiment, (b) is II sectional drawing of (a), (c) is soil dispersion | distribution by an up-down direction shunting blade piece Illustration. (A) is front expansion explanatory drawing of the diffusion wing | blade body as a 2nd modification of 10th Embodiment, (b) is the II-II sectional view taken on the line of (a).

Explanation of symbols

A Excavation / stirring tool G Unexcavated ground 1 Excavation / stirring shaft 2 Stirring blade 3 Kneading action blade 10 Kneading action body 11 Kneading action body 20 Diffusion blade body 21 Diffusion blade piece

Claims (7)

In the ground improvement device that improves the ground by discharging the improved material while excavating and stirring the ground, and kneading the improved material and the excavated soil,
In addition to providing a stirring blade and a kneading action blade on the outer peripheral surface of the excavation and stirring shaft extending in the vertical direction,
The stirrer blade is formed in an arc shape with its middle part bulging outward, and its base end is fixed to the outer peripheral surface of the excavation / stirring shaft, while being rotatably fitted around the peripheral surface of the excavation / stirring shaft The tip is loosely fitted to the outer peripheral surface of the combined boss part,
The kneading action blade includes the boss portion and a plurality of kneading action bodies formed by extending in the radial direction of the boss portion, and the tip of the kneading action body arranged outside the stirring blade is The tip of the kneading agent disposed inside the stirring blade is extended to a position near the bulging end of the stirring blade. Formed ,
Attach the diffusion blade to the radially extending part that forms the lower part of the stirring blade,
In the diffusion blade body, a pair of diffusion blade pieces extending in the rotation direction of the stirring blade are arranged in an opposing state, and the facing distance between the two diffusion blade pieces is set so that the excavated soil passing between the two diffusion blade pieces is diffused. An excavation / stirring tool for a ground improvement device, characterized in that the width is gradually increased from the downstream side to the upstream side in the rotation direction .   2. The excavation / stirring tool for a ground improvement device according to claim 1, wherein the kneading action body disposed inside the stirring blade is formed in an arc shape by expanding a midway portion outward.   An inner agitating blade was placed inside the kneading action body formed in an arc shape by expanding the middle part outward, and the inner agitating blade was fixed to the outer peripheral surface of the excavation / stirring shaft. The excavation / stirring tool for the ground improvement device according to claim 2.   The ground improvement according to any one of claims 1 to 3, wherein a guide rotating body that rolls along the unexcavated ground is attached to the tip of the kneading operation body disposed outside the stirring blade. Equipment excavation and stirring tool.   5. The excavation / stirring tool for a ground improvement device according to claim 4, wherein the guide rotator is movable forward and backward in the extending direction of the kneading operation body and elastically biased in the advancing direction.   The side surface of the kneading action body arranged outside the stirring blade is an inclined surface inclined with respect to the vertical direction, so that the kneading action body can roll and move along the unexcavated ground of the guide rotating body. 6. The excavation / stirring tool for a ground improvement device according to claim 4 or 5, wherein the excavation / stirring shaft rotates in conjunction with the excavation / stirring shaft.   At the lower end of the drilling / stirring shaft extending in the vertical direction, an agitating blade formed in an arc shape with the middle part bulging outward is attached, and a plurality of excavations are made in the radially extending portion that forms the lower part of the stirring blade The excavation / stirring tool for a ground improvement device according to any one of claims 1 to 6, wherein the blades are detachably mounted via a plurality of mounting bodies, respectively.

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