JP2022188475A - Ground improvement device - Google Patents

Abstract

To provide a small ground improvement device in low cost allowing co-rotation of sediment to be easily and securely prevented without using a co-rotation preventive board.SOLUTION: A ground improvement device 1 is to improve the ground by stirring and mixing the ground at a place through which a rod 5 is penetrated and solidification material ejected from a rotating stirring blade through rotating each of stirring blades 6 attached on at least upper and lower steps of a tip of the rod 5 with an auger motor connected at a base end of the rod 5, wherein the rod 5 is a double pipe, having an inner pipe 11 and an outer pipe 10 to freely rotate as connecting the inner pipe 11 with a rotating shaft of the auger motor as well as fixing the outer pipe 10 without connecting it with the rotating shaft of the auger motor to make the stirring blades at the lower step be normal rotation blades rotating in a same direction as the rotation of the auger motor as well as to make the upper stirring blades 6 at the upper step be reverse rotation blades rotating in a reverse direction to the rotation direction of the auger motor through a reverse mechanism 15 arranged between the inner pipe 11 and the outer pipe 10.SELECTED DRAWING: Figure 2

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soil improvement device for stirring and improving soil by discharging a solidifying material from rotating stirring blades.

As this type of soil improvement device, there is a soil improvement agitator with co-rotation prevention wings disclosed in Patent Document 1. This soil improvement stirrer includes an excavation stirring blade provided on a first rotating shaft, and a first bevel gear and a second bevel gear on a second rotating shaft rotatably fitted on the first rotating shaft. and a second bevel gear and a third bevel gear on a third rotating shaft rotatably mounted on the first rotating shaft above the second rotating shaft. and a co-rotation prevention wing rotatably provided via the By rotating the co-rotation prevention blades in a direction opposite to the rotation direction of the excavation stirring blades provided on the first rotating shaft, even if the earth and sand begin to rotate together with the excavation stirring blades, the co-rotation prevention blades Since the rotation is restrained and the earth and sand are forcibly sheared, the earth and sand are prevented from co-rotating, and the earth and sand and the solidification material can be mixed and agitated.

Japanese Patent Application Laid-Open No. 2001-317036

However, in the conventional soil improvement agitator, since the first to third rotating shafts and the first to third bevel gears are indispensable, the structure is complicated and the cost is high, and the size of the entire device is increased. was inviting

Therefore, the present invention has been made to solve the above-described problems, and provides an inexpensive and small-sized ground improvement device that can easily and reliably prevent the co-rotation of earth and sand without using a co-rotation prevention plate. intended to provide

In the present invention, each stirring blade attached to at least the upper and lower stages of the tip of the rod is rotated by an auger motor coupled to the base end of the rod, and the ground where the rod is penetrated and the rotating stirring blade are discharged. In the soil improvement device for improving the ground by stirring and mixing the solidification material, the rod is a double pipe and has an inner pipe and an outer pipe, and either one of the inner pipe and the outer pipe is connected to the rotating shaft of the auger motor to be rotatable, and the other tube is fixed without being connected to the rotating shaft of the auger motor, and one of the upper stirring blade and the lower stirring blade is a forward rotating blade that rotates in the same direction as the rotation of the auger motor, and the other stirring blade is rotated in the opposite direction to the rotation direction of the auger motor via a reversing mechanism provided between the inner tube and the outer tube. It is characterized in that it is a reversing wing that rotates to.

ADVANTAGE OF THE INVENTION According to this invention, without using a co-rotation prevention plate, co-rotation of earth and sand can be simply and reliably prevented, and cost reduction and size reduction can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic side view which shows the ground improvement apparatus of one Embodiment of this invention. It is a schematic sectional view of the principal part of the said ground improvement apparatus. 3 is a cross-sectional view taken along line III-III in FIG. 2; FIG.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic side view showing a soil improvement device of one embodiment of the present invention, FIG. 2 is a schematic cross-sectional view of the main part of the ground improvement device, and FIG. 3 is a cross-sectional view along the III-III line in FIG.

As shown in FIGS. 1 and 2, the soil improvement device 1 rotates the stirring blades 6 and 7 attached to the upper and lower stages of the tip of the rod 5 by the auger motor 4 coupled to the base end of the rod 5. The ground is improved by stirring and mixing the ground at the location where the solidification material is penetrated and the slurry-like solidification material S discharged from the discharge port 8 of the rotating lower stirring blade 7 .

As shown in FIGS. 1 and 2, the rod 5 is a double tube, consisting of a metallic cylindrical outer tube (the other tube) 10 and a metallic cylindrical inner tube (one tube) 11. and The outer tube 10 moves up and down along a leader 2 erected on the front portion of the construction machine body via an elevation drive device 3 . The outer tube 10 is fixed so as not to rotate to the installation table 3A on which the elevation driving device 3 is placed. In addition, the outer tube 10 hangs down to the upper part of the upper stirring blade 6, which will be described later.

As shown in FIG. 1, the inner tube 11 rotates with its proximal end 11b connected to the rotating shaft 4a of the auger motor (driving device) 4. As shown in FIG. A drilling bit 12 is attached to the tip 11 a of the inner tube 11 . Furthermore, above the tip 11a of the inner tube 11, a pair of upper stirring blades (the other stirring blade) 6, 6 are attached via a gear box 20, and below that, a pair of lower Stirring blades (one stirring blade) 7, 7 are attached. The lower pair of stirring blades 7, 7 are normal rotating blades that rotate in the same direction as the rotation of the auger motor 4, and the upper pair of stirring blades 6, 6 are connected to the bottom portion 10a of the outer tube 10. It is a reversing wing that rotates in a direction opposite to the rotation direction of the auger motor 4 via a reversing mechanism 15 provided between the tip 11 a of the inner pipe 11 . In addition, the length of the upper pair of stirring blades 6, 6 which are reversing blades is formed to the same length as the length of the lower pair of stirring blades 7, 7 which are normal rotating blades (all stirring blades is a length that does not protrude radially from the normal rotation blade). Further, a discharge port 8 for discharging the slurry-like solidifying material S is provided on the lower side of each stirring blade 7 in the lower stage.

As shown in FIGS. 2 and 3, the reversing mechanism 15 includes a sun gear 16 fixed through the inner tube 11 and three support shafts 17 projecting from the bottom surface 10a of the outer tube 10, respectively. A planetary gear 18 that is rotatably supported and meshed with the sun gear 16, and an annular outer ring that meshes with the planetary gear 18 while a pair of upper stirring blades 6, 6 are attached to the outer peripheral surface 19a. It is composed of a gear 19 and a gear box 20 that covers the sun gear 16 , the planetary gear 18 , and the tooth portion 19 b of the outer ring gear 19 . The three support shafts 17 are fixed to the bottom surface portion 10 a of the outer tube 10 so as to be parallel to the axial direction of the outer tube 10 . The sun gear 16 is fixed through the inner tube 11 and rotates at the same speed as the inner tube 11 . In addition, the planetary gear 18 may be spherical in order to prevent positional deviation.

As shown in FIGS. 1 and 2, the gearbox 20 includes an upper cover 21 attached to the bottom surface 10a of the outer tube 10, a lower cover 22 attached to the lower end 17a of the support shaft 17, and an outer ring gear 19. and a case 19a consisting of an outer peripheral surface. With this configuration, the gearbox 20 is suspended below the outer tube 10 .

As shown in FIGS. 1 and 2, the upper cover 21 includes a disk-shaped cover body 21a, a circular insertion hole 21b through which the inner tube 11 penetrates, and a cylindrical shape extending downward from the outer peripheral edge of the cover body 21a. and a peripheral wall portion 21c. The lower cover 22 has a disk-shaped cover main body 22a, a circular insertion hole 22b through which the inner tube 11 penetrates, and a cylindrical peripheral wall portion 22c extending upward from the outer peripheral edge of the cover main body 22a. Between the peripheral wall portion 21c of the upper cover 21 and the peripheral wall portion 22c of the lower cover 22, the upper pair of stirring blades 6, 6 are attached to the outer peripheral surface 19a of the outer ring gear 19 so as to protrude in the radial direction thereof. and rotates in a direction opposite to the rotating direction of the pair of stirring blades 7, 7 in the lower stage.

According to the soil improvement device 1 of the embodiment described above, when the outer pipe 10 is penetrated into the ground 9, the slurry-like solidification material S is discharged from the discharge ports 8 of the pair of stirring blades 7, 7 in the lower stage. Then, the earth and sand of the ground 9 where the outer tube 10 penetrates and the slurry-like solidification material S are stirred and mixed via the upper pair of stirring blades 6, 6 and the lower pair of stirring blades 7, 7. , The ground is improved by creating an improved body (not shown) with a circular cross section.

Further, in this soil improvement device 1, a uniaxial rod 5 in which an inner pipe 11 is rotatably accommodated inside an outer pipe 10 is used. For this reason, it is possible to configure the counter-rotating stirring impeller with one widely used single-shaft auger without using a twin-shaft coaxial auger (construction machine). As a result, co-rotation of earth and sand is eliminated, and the lengths of the stirring blades 6 and 7 in the upper and lower stages can be made uniform, thereby solving the problem of intrusion failure due to the projection of the co-rotation prevention plate seen in a single-screw machine. be able to. In other words, it is possible to provide an inexpensive and small-sized ground improvement device 1 that can easily and reliably prevent co-rotation of earth and sand without using a co-rotation prevention plate unlike a single-shaft machine.

Incidentally, according to the above-described embodiment, the discharge port for discharging the solidifying material is provided in the lower stirring blade so that the solidifying material is discharged when the rod penetrates the ground. may be provided to discharge the solidifying material even when the rod is pulled out into the ground.

Further, according to the above embodiment, the stirring blades are provided on the upper and lower stages of the tip of the inner tube, respectively, but the stirring blades may be provided on the upper, middle and lower stages of the tip of the inner tube, respectively.

Furthermore, according to the above embodiment, the outer tube is fixed and the inner tube attached with the stirring blades is rotated by the auger motor. It may be rotated by an auger motor.

1 ground improvement device 4 auger motor (driving device)
4a rotating shaft 5 rod 6 upper stirring blade (the other stirring blade: reversing blade)
7 Lower stage stirring blade (one stirring blade: normal rotation blade)
8 discharge port 9 ground 10 outer pipe (other pipe)
10a bottom portion 11 inner tube (first tube)
11a distal end 11b base end 15 reversing mechanism 16 sun gear 17 support shaft 17a lower end 18 planetary gear 19 annular outer ring gear 19a outer peripheral surface (case)
19b tooth portion 20 gear box 21 upper cover 22 lower cover S solidifying material

Claims (5)

Each stirring blade attached to at least the upper and lower stages of the tip of the rod is rotated by an auger motor coupled to the base end of the rod, and the solidified material discharged from the ground where the rod penetrates and the rotating stirring blade. In a ground improvement device that improves the ground by stirring and mixing,
The rod is a double tube having an inner tube and an outer tube,
Either one of the inner tube and the outer tube is connected to the rotating shaft of the auger motor so as to be rotatable, and the other tube is fixed without being connected to the rotating shaft of the auger motor,
One of the upper stirring blade and the lower stirring blade is a forward rotating blade that rotates in the same direction as the rotation of the auger motor, and the other stirring blade is between the inner tube and the outer tube. A ground improvement device characterized by using a reversing wing that rotates in a direction opposite to the rotation direction of the auger motor via a reversing mechanism provided therebetween. The ground improvement device according to claim 1,
The reversing mechanism is
a sun gear fixed through said one tube;
a planetary gear rotatably supported by a support shaft projecting from the bottom surface of the other tube and meshed with the sun gear;
an annular outer ring gear having the other stirring blade attached to its outer peripheral surface and meshed with the planetary gear;
a gearbox that covers the sun gear, the planetary gear, and the teeth of the outer ring gear;
A ground improvement device characterized by comprising: The ground improvement device according to claim 2,
The gearbox is
a top cover attached to the bottom surface of the other tube;
a lower cover attached to the lower end of the support shaft;
a case consisting of the outer peripheral surface of the outer ring gear;
A ground improvement device characterized by comprising: The ground improvement device according to any one of claims 1 to 3,
The one tube is the inner tube,
The other tube is the outer tube,
The one stirring blade is the lower stirring blade,
The ground improvement apparatus, wherein the other stirring blade is the upper stirring blade. The ground improvement device according to claim 1 or 4,
A soil improvement apparatus, wherein at least the lower stirring blade is provided with a discharge port for discharging the solidification material.

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