JPH08120663A - Agitating apparatus for ground improvement - Google Patents

Abstract

PURPOSE: To construct a box-like solid body with smoothing applied sufficiently to corners of a rectangle that are areas to which agitating blades can hardly reach. CONSTITUTION: This apparatus is composed of agitating blades 3 and 3, provided in projection with an interval provided in the axial direction to the circumferential face of an excavation rod 2, and forming blades 4 positioned vetically at the middle between both of the agitating blades 3 and 3 and isolated from rotation of the excavation rod 2. The forming blades 4 are placed on corners of a rectangle in a size externally contacting with circular-arcs drawn in a planate view by the tips of the agitating blades 3 and fixed to the front end of arms 6 provided in projection in the direction of radius of the circular-arcs to a sleeve 5 surrounding the excavation rod 2 and being isolated from rotation of the excavation rod 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground improvement agitator for agitating and mixing excavated soil and a solidifying material to construct a solid body having a rectangular cross section.

[0002]

BACKGROUND OF THE INVENTION After completion of excavation of the ground by an excavation rod or after excavation at a certain depth, the solidified material discharged from the tip of the excavation rod and excavated soil are agitated and mixed by a stirring blade. In the method of constructing a solid body by this, the shape of the solid body is determined by the region through which the rotating stirring blade passes, so it is constructed in a cylindrical shape, but the planar shape of the upper structure supported by the solid body is Since the is usually rectangular, it is necessary to construct a solid body having a plane area larger than the bottom area to completely support the upper structure, and the efficiency of solid body construction is poor.

To address this problem, Japanese Patent Laid-Open No. 6-146267 proposes a device in which a box-shaped casing is fixed around a drill rod and the mixture is leveled by the casing. This is to form the mixture into a box by allowing the casing to pass after the stirring blades located below or above the casing stir the mixture, but the leveling at the corners on the plane of the casing is not uniform. Tends to be enough.

The present invention has been made in view of the above background, and proposes a stirrer capable of sufficiently smoothing the corners of a rectangle, which is a region that the stirrer does not reach.

[0005]

According to the present invention, a molding blade is arranged at a corner portion of a rectangle having a size that circumscribes an arc drawn by the tip of the stirring blade, and the molding blade is moved up and down together with a drill rod. , Level the rectangular corners of the area that the stirring blade does not reach.

[0006] The stirring blade is provided on the peripheral surface of the excavating rod so as to project at a distance in the axial direction thereof, and the molding blade is located on the vertical surface in the middle of both stirring blades and insulated from the rotation of the excavating rod. . A sleeve surrounding the excavation rod is arranged around the excavation rod while being insulated from the rotation of the excavation rod, and the molding blade is fixed to the tip of an arm protruding from the sleeve in the radial direction of the arc drawn by the stirring blade.

Since the forming blade is insulated from the rotation of the excavating rod, it rises and descends as the excavating rod moves up and down while maintaining the position on the plane due to the resistance of the soil even when the stirring blade rotates, and the rectangular corner portion during the ascending and descending. The mixture present in 1) is leveled according to the shape of the molding blade, and the mixture is molded into a rectangular shape together with a stirring blade that molds the mixture into a circular shape.

Particularly, the molding blade has a shape approximated to a triangle from two sides of a rectangle having a size that circumscribes the arc drawn by the tip of the stirring blade on a plane and a part of the arc that inscribes it.
The wedge-like shape in which the cross-sectional area is reduced from the center to the upper and lower ends on the vertical surface reduces the resistance to penetration into the excavated soil, and at the same time, once the mixture is taken into the excavating rod side, the excavating rod is re-introduced It is possible to guide the mixture to the outer peripheral side and level the mixture according to the planar shape of the molding blade, and the leveling effect in the rectangular corners is improved.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIGS. 1 and 2, an agitator 1 of the present invention includes agitating blades 3 and 3 projecting from the peripheral surface of a drilling rod 2 at a distance in the axial direction thereof, and an elevation surface. , A solidified material which is located in the middle of the two stirring blades 3 and 3 and which is insulated from the rotation of the excavating rod 2 and is discharged through the excavating rod 2 during excavation of the ground by the excavating rod 2 or during extraction. It is a device that stirs and mixes excavated soil and mixes the mixture into a rectangular cross-sectional shape.

As shown in FIG. 1, the molding blade 4 is arranged in a rectangular corner portion of a size that circumscribes the arc drawn by the tip of the stirring blade 3 as shown in FIG. 1, that is, in a region outside the stirring blade 3. . A sleeve 5 that surrounds the drilling rod 2 is arranged around the drilling rod 2 while being insulated from the rotation of the drilling rod 2. At the tip of an arm 6 projecting in the radial direction of the arc drawn by the stirring blade 3 on the sleeve 5. The molding wing 4 is fixed. The sleeve 5 is locked to stoppers 7 and 7 fixed to the excavating rod 2 at the upper and lower positions thereof, and the relative movement in the vertical direction with respect to the excavating rod 2 is restricted, and the molding blade 4 follows up and down movement of the excavating rod 2. Since the forming blade 4 is insulated from the rotation of the excavating rod 2, it moves up and down together with the excavating rod 2 while maintaining the position on the plane due to the resistance of the soil even when the stirring blade 3 rotates.

On the plane, the molding blade 4 has a shape similar to a triangle from two sides of the above-mentioned rectangle and a part of a circular arc inscribed therein, and the cross-sectional area is reduced from the center to the upper and lower ends on the elevation. It has a wedge shape, and generally has a shape in which two triangular pyramids are joined at the bottom surface as shown in FIGS. In FIG. 2, the inside of the molding blade 4 is shown to be solid, but the inside may be hollow because it does not relate to the function.

The forming blade 4 has a wedge shape symmetrically up and down from the center, and the upper and lower ends are vertices. Therefore, the blade 4 is not only in the excavated soil or in the mixture at the corners of the rectangle during both descent and ascent. It penetrates without resistance, and the inclined surface facing the excavation rod 2 side guides the excavated soil and the mixture to the center side of the rectangle, and the stirring blade 3
To aid in stirring. This inclined surface 41 guides the excavated soil and the mixture to the center side of the rectangle at the portion on the advancing side of the excavating rod 2 as shown by the arrow in FIG. In order to guide from the side to the peripheral side, that is, to the corner side of the rectangle, after the molding blade 4 passes, the mixture is molded into a rectangular shape with the mixing by the stirring blade 3.

[0013]

The present invention is as described above, and the forming blades are arranged at the corners of a rectangle having a size that circumscribes the arc drawn by the tips of the stirring blades, and the forming blades are moved up and down together with the excavating rod. Therefore, it is possible to sufficiently flatten the corners of the rectangle in the area that the stirring blade does not reach.

In particular, if the forming blade is shaped like a triangle on a plane and has a wedge shape on the elevation, the resistance at the time of penetrating into the excavated soil is reduced, and at the same time, the mixture of the mixture is changed depending on the shape of the forming blade. Can be leveled, and the leveling effect at the rectangular corners can be improved.

[Brief description of drawings]

FIG. 1 is a plan view showing a stirring device.

FIG. 2 is a sectional view taken along line xx of FIG. 1;

FIG. 3 is a view taken along the line yy of FIG.

[Explanation of symbols]

1 ... Stirrer, 2 ... Drilling rod, 3 ... Stirrer, 4
...... Molding wing, 41 …… Sloping surface, 5 …… Sleeve, 6 …… Arm, 7 …… Stopper.

Claims (2)

[Claims] 1. A device for agitating and mixing solidified material and excavated soil discharged through the excavating rod when excavating the ground with the excavating rod or extracting the mixture, and molding the mixture into a rectangular cross-sectional shape. On the surface, a stirring blade projecting at a distance in the axial direction, and a molding blade located in the middle of both stirring blades on the vertical surface and insulated from the rotation of the excavating rod. An arm that is located at a corner portion of a rectangle that is sized to circumscribe the arc drawn by the tip of the stirring blade and surrounds the excavation rod and is insulated from its rotation to project in the radial direction of the arc. A ground improvement agitator characterized by being fixed to the tip of the ground. 2. The molding blade has a two-sided rectangular shape having a size that circumscribes the arc drawn by the tip of the stirring blade and a part of the arc that is inscribed in the arc, and is shaped like a triangle. The ground improvement agitator according to claim 1, wherein the surface has a wedge shape whose cross-sectional area decreases from the center to the upper and lower ends.