JPH1096231A - Excavating and stirring device for soil improvement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excavating and stirring device capable of increasing mixing efficiency of a clod with improvement material by finely crashing the clod resulting from cutting operation of an excavating wing. SOLUTION: An excavating and stirring device is equipped with an excavating wing 1 providing a supplying passage of improvement material linked with an outlet 32 to the lower part of a non-rotatable driving shaft 4 to rotate, a crushing and cutting wing 2 provided to the driving shaft 4 so as to approach the excavating wing 1 to be positioned upward thereof and rotating to the excavating wing 1 relatively in the opposite direction and a stirring wing 3 provided to the driving shaft 4 so as to approach the crushing and cutting wing 2 to be positioned upward thereof and rotating to the crushing and cutting wing 2 relatively in the opposite direction. Then, it is also equipped with driving mechanisms 8, 12, 13, 14... provided to the inside of the driving shaft 4, rotating and driving the excavating wing 1 and for rotating and driving both of the crushing and cutting wing 2 and stirring wing 3 or one of them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavating and stirring apparatus for improving a ground, and more particularly, to excavating and stirring an improving material such as a cement slurry while excavating and stirring a soft ground to construct an improved pillar. It relates to a drilling and stirring device.

[0002]

2. Description of the Related Art A mechanical mixing method is known as one of deep mixing treatment methods for improving the ground by mixing and stirring a soft soil and an improving material at the current position. This method uses a device equipped with a drilling wing and a stirring blade on the drilling shaft, pours the improving material into the excavated earth and sand cut by the drilling wing, and mixes and mixes the excavated soil and the improving material with the stirring blade. .

In such a construction method, since the excavated earth and the agitating blade rotate together with the agitating blade alone and the mixing and agitation with the improved material are insufficient, an apparatus in which an excavating shaft is further provided with an anti-rotating blade is proposed. (For example, Japanese Patent Publication No. 58-2937).
No. 4). However, although the improvement of the mixing efficiency of the excavated earth and sand and the improvement material can be expected to some extent by the installation of the anti-corotating wings, the mixing and stirring are still insufficient. In other words, what is produced by the cutting action of the excavating wing is the earth mass, and unless the earth mass is finely crushed, the mixing with the improving material is not sufficiently performed. Such a phenomenon is particularly remarkable when the soil of the ground to be improved is, for example, a cohesive soil having a large adhesive strength.

[0004]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above technical background, and has the following objects.

[0005] An object of the present invention is to provide a ground improvement excavating and stirring device capable of increasing the efficiency of mixing and kneading with an improving material by finely crushing, cutting or grinding the earth mass generated by the cutting action of the excavating wing. To provide.

[0006]

The present invention employs the following means to achieve the above object.

That is, the present invention provides a rotating excavation wing provided below a non-rotating propulsion shaft in which a supply path for an improving material communicating with a spout is provided. A crushing cutting wing that is provided on the propulsion shaft so as to be located in a direction opposite to the excavating wing, and is disposed close to and above the crushing cutting wing on the propulsion shaft. A stirring blade that is provided and rotates in the opposite direction relative to the crushing cutting blade; and a stirring blade that is provided inside the propulsion shaft to rotationally drive the excavating wing and that one or both of the crushing cutting blade and the stirring blade are provided. And a drive mechanism for rotationally driving the excavation / stirring apparatus for ground improvement.

Further, in the present invention, the front surface in the rotation direction of the excavating blade is inclined upward, the front surface in the rotational direction of the crushing cutting blade relative to the excavating blade is inclined upward, and the relative position of the stirring blade to the crushing cutting blade is increased. The excavation and stirring device for ground improvement is characterized in that the front surface in the rotation direction is inclined downward.

Further, in the present invention, at least two digging wings are provided at the same height position, and a plurality of digging blades are provided at a lower edge of each of the digging wings at intervals in a radial direction. The digging and stirring apparatus for ground improvement is characterized in that the digging blades of the wing are arranged so that their rotation trajectory is different from the rotation trajectories of the respective digging blades of the other digging wings.

[0010] The drilling and stirring device according to the present invention includes a drilling wing,
The blade includes three types of blades, a crushing blade and a stirring blade. The crushing blade rotates relative to the excavating blade, and the stirring blade rotates in the opposite direction relative to the crushing blade. Here, the relative reverse rotation of the wing includes not only the case where the wing rotates in the opposite direction with respect to the other wings, but also the case where the wing does not rotate with respect to the ground. The following combinations are mentioned as those aspects.

[0011] The forward rotation means the direction of rotation of the excavation wing. You can use either clockwise or counterclockwise. When the stirring blade rotates in the same direction as the excavator blade, it is preferable that the rotation speed of the stirring blade be higher than the rotation speed of the excavator blade.

[0012] Due to the rotation relationship of the respective wings, the following effects occur during excavation and agitation of the improved ground. That is, as shown in FIG. 1, the ground is cut by the rotating excavation wing 1 as the earth mass B1, and the earth mass B1 exerts a large shearing action by the crushing cutting wing 2 rotating in the opposite direction relative to the excavation wing 1. It is crushed or cut into small lumps B2. The small lumps B2 are again subjected to a large shearing action by the stirring blades 3 rotating in the opposite direction to the crushing and cutting blades 2, and are further finely crushed or cut, and simultaneously stirred and mixed. The amendment material is discharged from a spout above the excavation wing in the process of crushing or cutting the earth mass. Therefore, the excavated earth and sand and the improving material are sufficiently mixed, stirred and kneaded, and a high quality improved pillar is constructed. Since the earth and sand and the improving material have high viscosity, the intervals between the blades are set close to each other so that the effects of crushing, cutting, shearing, mixing, stirring, and refining substantially occur.

By setting the front surface in the rotation direction of the excavating wing 1 to an upwardly inclined surface, the earth mass B1 is scooped up along the inclined surface. Similarly, by making the front surface of the crushing and cutting blade 2 relative to the excavation blade 1 in the rotational direction an upwardly inclined surface, the small mass B2 is scooped up along the inclined surface.
Furthermore, by making the front surface of the stirring blade 3 relative to the crushing and cutting blade 2 a downward inclined surface in the direction of rotation, the small lumps B2 are subjected to the crushing action by the inclined surface in addition to the shearing action, and are finely crushed. Efficiency is improved. Although the blade shape of each of the blades is a preferred embodiment, the present invention is not limited to the blade shape. For example, the front surface of the crushing cutting blade 2 may have a vertical or slightly downward inclined surface or / and stirring. The one in which the front surface of the wing 3 is a vertical surface is also included.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a sectional view showing an embodiment of the excavating and stirring apparatus according to the present invention, FIG. 3 is a sectional view taken along line AA of FIG. 2, FIG. 4 is a sectional view taken along line BB of FIG. C
FIG. 4 is a sectional view taken along line C of FIG. The propulsion shaft 4 is a hollow, non-rotating shaft, and three mounting hubs 5, 6,
7 are rotatably fitted via sealing members (not shown), and the excavating wing 1, the crushing cutting wing 2, and the stirring wing 3 are attached to these mounting hubs 5, 6, and 7, respectively.
That is, the crushing blade 2 is placed above the excavating blade 1 and the stirring blade 3
Are disposed above and adjacent to the crushing blade 2. More specifically, the mounting hubs 5, 6, and 7 have a structure in which a lower portion of the mounting hub 6 is fitted to an upper outer periphery of the mounting hub 5, and a lower portion of the mounting hub 7 is fitted to an upper outer periphery of the mounting hub 6. It has become.

A hollow drive transmission shaft 8 extending inside the propulsion shaft 4 has an axis coinciding with the axis thereof. Drive transmission shaft 8
, The rotational force of the drive shaft 11 is transmitted via gears 9 and 10 meshing with each other in the propulsion shaft 4. The drive transmission shaft 8 has drive gears 12, 1, 1 located inside the mounting hubs 5, 6, 7.
3 and 14 are fixed respectively.

A plurality of driven gears 15 mesh with the driving gear 12 inside the mounting hub 5. These driven gears 1
5 is housed in an opening 16 formed in the peripheral wall of the propulsion shaft 4,
The gear meshes with an internal gear 17 provided on the inner periphery of the mounting hub 5 (see FIG. 3). Thereby, the rotational force in the same direction as that of the drive transmission shaft 8, that is, in the positive direction is transmitted from the drive transmission shaft 8 to the mounting hub 5.

A plurality of driven gears 19 mesh with the driving gear 13 inside the mounting hub 6 via a plurality of idler gears 18. The idler gear 18 and the driven gear 19 are accommodated in an opening 20 formed in the peripheral wall of the propulsion shaft 4, and the driven gear 19 meshes with an internal gear 21 formed on the inner periphery of the mounting hub 6 (FIG. 4). reference). Thus, a rotational force in the opposite direction is transmitted from the drive transmission shaft 8 to the mounting hub 6.

The drive transmission mechanism provided inside the mounting hub 7 is the same as that in the mounting hub 5 except for the gear ratio. That is, a plurality of driven gears 2
2 are engaged. These driven gears 22 are connected to the propulsion shaft 4
And is engaged with an internal gear 24 provided on the inner periphery of the mounting hub 7 (see FIG. 5). Thereby, the mounting hub 7 is connected to the drive transmission shaft 8 from the drive transmission shaft 8.
A rotational force in the same direction, that is, a positive direction is transmitted.

With the above configuration, the excavating blade 1, the crushing and cutting blade 2, and the stirring blade 3 rotate in the forward, reverse, and forward directions, respectively, via the mounting hubs 5, 6, and 7. Crushed cutting wing 2
Is fixed to a boss 27 fitted to a spline 26 formed on the outer periphery of the mounting hub 6. Accordingly, the crushing blade 2 is rotated by the rotation of the mounting hub 6 and
It is movable within a predetermined range in the axial direction.

As shown in FIG. 6, the excavation wing 1 has its front surface in the rotational direction inclined upward. The crushing cutting blade 2 has its front surface in the rotation direction inclined upward. Further, the stirring blade 3 has its front surface in the rotation direction inclined downward. Such a wing shape is the same in another embodiment described later. The excavating wing 1, the crushing and cutting wing 2 and the stirring wing 3
Although two sheets are provided at the same height position, three or more sheets may be provided.

Referring to FIG. 2 again, a plurality of digging blades 30 are provided on the lower edge of the digging wing 1 at intervals in the radial direction. Each of the excavating blades 30 provided on the two excavating blades 1 has a rotation locus of the excavating blade 30 of one of the excavating blades 1 and the other of the excavating blades 1.
Are arranged so that the rotation locus of the excavating blade 30 is different. With such an arrangement, it is possible to excavate finely over the entire excavation surface. Such a digging blade 3
The arrangement of 0 is the same for another embodiment described later. The excavation blade 30 is also provided at the lower end of the propulsion shaft 4.

In the propulsion shaft 4 inside the mounting hub 5, a chamber 31 of an improving material such as cement slurry is formed. The drive transmission shaft 8 is formed of a hollow shaft, and the lower end is supported by the upper wall of the chamber 31. Improved material is drive transmission shaft 8
Is supplied to the chamber 31 through a supply path inside the chamber 31. In the upper part of the excavation wing 1, a plurality of outlets 32 for improving material are provided. These outlets 32 communicate with the chamber 31 via the flow path 33, and the improving material supplied to the chamber 31 is discharged from the outlet 32.

FIG. 7 is a sectional view showing a construction state using the apparatus of the above embodiment. A propulsion force into the ground is given to the propulsion shaft 4 by a press-fit device (not shown). At the same time, the drive shaft 11 is rotated by the drive of an electric motor or the like (not shown), and the rotational force is transmitted to the mounting hubs 5, 6, and 7 via the drive transmission shaft 8 and the gear train, and the digging blade 1, the crushing blade 2
And the stirring blade 3 rotates. Further, the improved material is poured out from a spout 32 provided in the excavation wing 1. As described above, the rotation of the digging blade 1 and the stirring blade 3 is normal rotation, and the rotation of the crushing cutting blade 2 is reverse rotation. The rotation speed of the stirring blade 3 is the highest, and the rotation speed is lower in the order of the crushing blade 2 and the excavating blade 1.

The ground is excavated by the rotation of the excavation wing 1, and the state at this time is schematically shown in FIGS. 1 (a) and 1 (b). That is, the ground is cut by the excavation wing 1 as the earth mass B <b> 1 and is scooped up along the inclined surface of the excavation wing 1. The earth mass B1 is subjected to a large shearing action by the crushing blade 2 rotating in the direction opposite to the excavation wing 1, and is crushed or cut into small masses B2. The small lumps B2 are further scooped up along the inclined surface of the crushing and cutting blade 2, and are again subjected to a large shearing action and a crushing action by the stirring blade 3 rotating in the opposite direction to the crushing and cutting blade 2, and further crushed or Cut and mashed.

The improving material is discharged from the spout 32 in the process of crushing or cutting the earth mass. The improving material is mixed with the finely crushed or cut and ground excavated earth and sand, and is stirred and mixed by the stirring blade 3 rotating at high speed. Therefore, the excavated earth and sand and the improving material are sufficiently mixed, stirred, and kneaded, and a high-quality improved pillar is constructed.

Relatively large gravel, boulders, etc. are mixed in the ground to be improved, and even if these are caught between the excavating wing 1 and the crushing blade 2, the crushing blade 2 rises in the axial direction. As a result, no malfunction occurs.

The above embodiment is particularly effective when the ground to be improved is a viscous soil or the like having a large adhesive strength, since both the crushing and cutting blades 2 and the stirring blades 3 are absolutely rotated by the driving mechanism. Depending on the soil quality of the present invention, the present invention may employ the following embodiments.

FIG. 8 is an axial sectional view showing another embodiment of the present invention. In this embodiment, the mounting hub 6 of the crushing blade 2 is fixed to the propulsion shaft 4 and the crushing blade 2
Does not rotate. The rotation of the stirring blade 3 in the same direction (positive direction) as the excavating blade 1 by the drive mechanism is the same as in the embodiment shown in FIG.

Although the crushing and cutting blade 2 is not rotating, a relative reverse rotation occurs between the crushing and cutting blade 2 and the digging wing 1, so that a shearing action on the digging sediment occurs, and the digging and sediment is crushed or cut. . In this embodiment, the crushing blade 2 may be directly fixed to the propulsion shaft 4 without using the mounting hub 6.

FIG. 9 is an axial sectional view showing still another embodiment of the present invention. In this embodiment, as in the embodiment shown in FIG. 8, the mounting hub 6 of the crushing blade 2 is fixed to the propulsion shaft 4, and the crushing blade 2 does not rotate. The drive gear 14 of the stirring blade 3 has an idle gear 35.
The driven gear 36 is meshed with the driven gear 36 via the. Therefore,
The stirring blade 3 rotates in the direction opposite to the direction of the excavating blade 1. In addition, in the case of this embodiment, the mounting mode of the stirring blade 3 is opposite to that shown in FIG.

Also in this embodiment, the crushing blade 2
, A relative reverse rotation occurs with the excavation wing 1, so that a shearing action is exerted on the excavated earth and sand, and the excavated earth and sand is crushed or cut. Further, since the stirring blade 3 rotates in the direction opposite to the direction of the excavating blade 1, the stirring, mixing, and mixing efficiency does not decrease.

FIG. 10 is an axial sectional view showing still another embodiment of the present invention. In this embodiment,
The mounting hub 7 of the stirring blade 3 is fixed to the propulsion shaft 4, and the stirring blade 3
Does not rotate. The crushing and cutting wing 2 is driven by the driving mechanism so that
The rotation in the opposite direction is the same as in the embodiment shown in FIG.

Although the stirring blade 3 is non-rotating, a relative reverse rotation occurs between the stirring blade 3 and the crush cutting blade 2. In addition to being subjected to shearing action and crushing action, it is further crushed or cut / ground. Also in the case of this embodiment, the stirring blade 3 may be directly fixed to the propulsion shaft 4 without using the mounting hub 7.

In any of the above-mentioned embodiments, the crushing blade 2 and the stirring blade 3 are arranged close to the excavating blade 1 and the crushing shear blade 1, respectively. This can give the excavated soil a greater shearing action, and can also be crushed, cut / ground, agitated,
Can be reworked.

In each of the above embodiments, the length of each of the crushing blade and the stirring blade (the dimension from the axis of the propulsion shaft to the tip of the blade) is equal to the length of the excavating blade. As described above, since the length of each of the crushing cutting blade and the stirring blade is set to be equal to or less than the length of the drilling wing, the crushing cutting blade and the stirring blade are pressed into the digging range by the drilling wing, and the press-in resistance becomes small. .

[0036]

As described above, according to the present invention, the excavated soil mass is finely crushed or cut / ground by the shearing action generated between the excavating wing, the crushing / cutting wing and the stirring blade. Are sufficiently mixed, stirred and kneaded, and a high quality improved pillar can be built.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining an operation.

FIG. 2 is an axial sectional view showing an embodiment of the present invention.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

FIG. 5 is a sectional view taken along line CC of FIG. 2;

FIG. 6 is a side view of the embodiment.

FIG. 7 is a sectional view showing a construction state according to the embodiment.

FIG. 8 is an axial sectional view showing another embodiment.

FIG. 9 is an axial sectional view showing still another embodiment.

FIG. 10 is an axial sectional view showing still another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Excavating blade 2 ... Crushing cutting blade 3 ... Stirring blade 4 ... Propulsion shaft 5, 6, 7 ... Mounting hub 8 ... Drive transmission shaft 11 ... Drive shaft 12, 13, 14 ... Drive gear 15, 19, 20 ... Follower gear 18 play gear 26 spline 27 boss 31 chamber 32 spout

Claims (3)

[Claims] 1. A rotating excavation wing provided at a lower portion of a non-rotating propulsion shaft formed therein with a supply path of an improving material communicating with a spout, and located near and above the excavation wing. A crush cutting blade that is provided on the propulsion shaft and rotates in the opposite direction relative to the excavation wing, and is provided on the propulsion shaft so as to be located close to and above the crush cutting blade, A stirring blade that rotates in the opposite direction relative to the crushing blade, and a rotating blade that is provided inside the propulsion shaft and drives the excavating blade, and rotationally drives one or both of the crushing blade and the stirring blade. And an excavating and stirring apparatus for improving the ground. 2. A front face in a rotational direction of said cutting blade is inclined upward, a front face in a rotational direction of said crushing cutting blade relative to said cutting blade is inclined upward, and a front surface of said stirring blade in a rotating direction relative to said crush cutting blade. The excavation and stirring device for ground improvement according to claim 1, wherein the is inclined downward. 3. The apparatus according to claim 1, wherein said excavation wing is at least two
A plurality of digging blades are provided at a lower edge of each of the digging wings at intervals in a radial direction, and the digging blades of the digging wings have their rotational trajectories of other digging wings. The excavation and stirring device for ground improvement according to claim 1, wherein the excavation and stirring device is arranged so as to be different from the rotation locus of each excavation blade.