JPS58120915A - Improving device for soft ground - Google Patents

Abstract

PURPOSE:To enable automatic switching of discharge of slurry at a lowering time and a rising time of a hollow agitating shaft, by a method wherein a shaft cylinder is engaged slidably in an axial direction with the lower end of the agitating shaft, and holes are bored in the upper part and the lower part of the shaft cylinder. CONSTITUTION:If a hollow agitating shaft 16 is lowered into a soft ground as it turns, agitating blades 22-24 meet with resistance of soil, and a shaft cylinder 20 united in one body with the agitating blades 22-24 is raised to an uppermost position against an agitating shaft 16. Under this condition, slurry is discharged to the outside through a center hole 16b of the agitating shaft 16, a lower hole 16e, a lower hole 20a of the cylinder 20, a passageway 22a of the lowermost agitating blade 22, and a discharge port 22b. Conversely, if the agitating shaft 16 is raised, the axial cylinder 20 is lowered to a lowermost position against the agitating shaft 16, and under this condition, slurry is discharged to the outside through the center hole 16b of the agitating shaft 16, an upper hole 16d, an upper hole 20b of the shaft cylinder 20, a passageway 23a of the uppermost agitating blade 23, and a discharge port 23b.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a soft ground improvement device that injects slurry into soft ground and agitates the slurry with a stirring blade to harden the ground.

Figures 1 to 4 show an example of a conventional soft ground improvement device. 41 [X, g is a reel tower, j is a fixed reel pivoted at the upper end of the reel tower L,
6 is a lifting reel that can be raised and lowered along the reel tower Buddha, 7
1 is a flexible hose for feeding slurry connected to the upper part of the stirring shaft via a reel tower, and 1 is a wired pipe connected to the flexible hose 7.

However, this type of device discharges slurry from the lowest stirring blade 3 when rotating the stirring shaft λ while pushing it down into the soft ground, and discharges slurry from the highest stirring blade 3 when lifting the stirring shaft λ while rotating. In order to effectively discharge the slurry, each stirring shaft is equipped with one system of slurry feed channels, as shown in FIGS. 3 and 4. , just in case you need 10. One slurry feeding path 9 communicates with a passage provided in the lowest stirring blade 3 so that the slurry is discharged from the slurry discharge port 12, and the other slurry feeding path 1O communicates with a passage provided in the lowest stirring blade 3. Nine passages 13 are installed in wing 3.
Make sure that the slurry is in communication with the slurry outlet/liter so that it is discharged from the slurry outlet. Note that 15 (see diagram) is a check valve made of a rubber plate, and %ja#λb is a 7-lunge for the joint of the stirring shaft λ.

As mentioned above, in the conventional device, 2
Since this slurry feed path is required, one pipe t is required from ■ to ■ as shown in the IE/figure, and the wash water return pipe t' is also connected to each of the r pipes. , just in case the piping is very complicated.

@1 In the figure, each pipe is equipped with a magnetic flow meter, P
is a pressure gauge, ■ is a three-way switching valve.

As shown in Figure 2, it is necessary to provide slurry feed passages 9 and 10 of the nl system in the stirring shaft 2, and for this reason, in manufacturing, the stirring shaft is located at the lower part in addition to the upper flange part a. 7
Since it is necessary to divide the position of the swing rod b, the structure of the conventional device becomes complicated and the manufacturing cost increases, and the stirring shaft 2
Since the lower part of the flange must be connected through the flange part b, there was a problem that this flange part increased the resistance of the soil.

This invention was made with the aim of solving the above-mentioned problems, and by making it possible to have only one slurry feeding path in the stirring shaft, and by forming the lower part of the stirring shaft integrally without dividing it, Is it possible to solve the above problems? This is the purpose.

An embodiment of the present invention will be described below with reference to FIGS. In the figure, 76 is a stirring shaft that can be moved up and down and rotated.
a is a flange for a joint.

In the present invention, the stirring shaft 6 is hollow, its center hole 4b is used as a slurry feeding path, and the lower part 4c of the stirring shaft 1b is formed into a rectangular tube shape (hexagonal shape in this example). However, a plurality (three in this example) of horizontal holes/6d are provided in the upper part of this corner S part/4 Ci, and a plurality (three in this example) of horizontal holes/6d are provided in the lower part of the square tube part/40. A horizontal hole /4e is provided, and a stopper plug 1 of the center hole /4b is provided below the horizontal hole /48.
7, and approximately elliptical grooves /6f as shown in FIG. Insert 1.

An upper stopper /9 is formed at the top of the rounded square cylinder part /AC, a shaft cylinder 2772 is fitted into the square cylinder part /40 below it, and a substantially conical lower stopper 2 is formed at the bottom of the square cylinder part /40. / screw in and secure. The axis wJ〃 is made to rotate together with the rectangular tube part /≦C, and in the axial direction is a certain range 5 (
When the barrel is at the top as shown in Fig. 5, a hole ga communicating with the horizontal hole /46 is provided in the barrel, and this hole jff &. When the lowest stirring blade n having a communicating passage 22a and a slurry discharge port 22b communicating with the passage 22a projects from the shaft @Xt, and the shaft cylinder is at the lowest position as shown in FIG. A hole Jb communicating with the horizontal hole /6d is provided in the shaft cylinder, and this hole
The uppermost stirring blade n, which has a passage 2Ja communicating with b and a slurry discharge port gb communicating with this passage 27a, is connected to the shaft tube X.
Further, a stirring blade 2 is protruded from the connecting portion of the shaft cylinder X.

Next, the operation of the apparatus of the present invention constructed as described above will be explained. When the stirring shaft/6 configured as described above is rotated and pushed into soft ground, the stirring blades n, n, s will encounter resistance from the soil, so the shaft integrated with each stirring blade n, n, 2# The tube X moves to the uppermost position as shown in FIG. In this state, in order to ensure that the horizontal hole l≦e provided in the lower part of the square tube part 16C with the stirring shaft l≦ communicates with the hole 2117a of the shaft tube X, the center hole /4b is opened from the top of the stirring shaft l The slurry fed through is discharged to the outside from the slurry discharge port nb via the hole/68S2Da and the passage 22a.

At this time, since the horizontal hole /4d provided in the upper part of the square cylinder part /6c is closed by the shaft cylinder J, no slurry is discharged from the uppermost stirring blade n.

In addition, when pulling up the stirring shaft 16, the shaft tube integrated with the stirring blades n, 2J, and 2F descends with respect to the stirring shaft 1B as shown in FIG. 6 due to the resistance of the soil. The horizontal hole /4 e is closed at the bottom of the hole, and the corner m part /4
The horizontal hole /6d provided in the upper part of the shaft communicates with the hole b of the shaft cylinder. For this reason, it is fed from the top of the stirring shaft/B through the center hole/1! #The slurry is discharged to the outside from the slurry discharge port 2Jb via the hole/6dSXlb and the passage na.

As described above, the apparatus of the present invention is very convenient because the slurry discharge is automatically switched between when the stirring shaft 1 is lowered and when it is raised. And the slurry feeding system is the same as before.
Since no system is required and only one system is sufficient, the structure of the stirring shaft/4 is simple, and the conventional 14 piping system is sufficient, making manufacturing easier and significantly reducing manufacturing costs. Furthermore, according to the present invention, there is no need to connect the stirring blades using a axial 7-lunge joint as in the past.
The effect of reducing the resistance of the soil is also obtained.

[Brief explanation of the drawing]

Figure 1 is a partial explanatory diagram showing an example of a conventional soft ground improvement device, Figure 2 is an elevational view of its main parts, Figure 3 is a cross-sectional plan view taken along line I-1, and Figure 4 is a stirring shaft. Detailed cross-sectional view of the lower part,
Figure IEj is a longitudinal sectional elevational view showing the essential parts of the device of the present invention, Figure 7 is an explanatory diagram of its operation, Figure 7 is a cross-sectional plan view taken along the line -■ in Figure 6, and Figure 7 is a cross-sectional view of the rectangular tube section. It is a partial view showing a side. /l... Stirring shaft, #; a... 7 langes for joint, 16
b...Center hole, 160...Square tube part, /4 (i I
/46...Horizontal hole, t6 f...Substantially oval groove,
...stop &, tt...OUng, /9...upper stopper, ... shaft cylinder, xa, x'o...hole, 1...
・Lower stopper, 〃... Stirring blade, 22a... Passage,
22b...Slurry discharge port, n...Stirring 12J5L
...Passage, 2Jb...Slurry discharge port, λri...
stirring blade. Patent applicant: Kishin Construction Co., Ltd.

Claims (1)

[Claims] L A shaft cylinder is fitted to the lower end of the hollow stirring shaft, and this shaft cylinder is made to rotate together with the stirring shaft, and also to be able to slide within a certain range in the axial direction. A blade is provided, and when this shaft cylinder is at the upper limit position, the slurry that has passed through the inside of the stirring shaft passes through the lowest stirring blade and is discharged from the slurry discharge port, and when the shaft cylinder is at the lower limit position, the slurry A soft ground improvement device characterized in that the slurry is discharged from the slurry discharge port through the top stirring blade.