JPH09108561A - Modifier outlet switching device in deep-mixing agitator - Google Patents

Abstract

(57) [Abstract] (Corrected) [PROBLEMS] Automatically switching the discharge of the slurry-like modifier to the lower or upper discharge port with a simple structure depending on the rotation direction of the stirring rotary shaft at the time of penetration and extraction. An improvement agent discharge port switching device is proposed. SOLUTION: A cylindrical valve body 4 is supported horizontally and rotatably in a circumferential direction in a stirring rotary shaft 1 at an upper discharge port 20 position, and the valve body 4 is provided with an upper side of an improving agent by its rotation angle. A communication pipe 5 that directly connects the supply pipe and the lower supply pipe and a communication hole 6 that connects the upper supply pipe and the upper discharge port 20 of the rotary shaft 1 are provided, and are substantially the same as the valve body 4 of the rotary shaft 1. On the outside of the height position, a slewing plate 8 which projects laterally and can swivel in the horizontal direction by the earth pressure due to the rotation of the rotating shaft 1 in the soft soil is pivotally supported.
An improving agent in a deep-layer mixing agitator, characterized in that the valve body 4 is configured to be rotationally driven by a predetermined angle by rotating a pulley 7 on the outer side of a rotary shaft that is coaxially fixed to the valve body 4 via Outlet switching device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching device for a slurry-like improving agent discharge port in a deep-layer mixing agitator, and more particularly, to a hollow tubular agitating rotary shaft of a deep-layer agitating device used in a method for improving soft ground. It is equipped with a valve body for switching the improver's discharge port up and down, and automatically switches the discharge agent from the lower discharge port at the lower end when the rotary shaft penetrates and from the upper discharge port when the rotary shaft is pulled out. The present invention relates to an automatic switching device for upper and lower discharge ports.

[0002]

2. Description of the Related Art A slurry-like improving agent such as cement-based solidifying agent, water glass, mortar, quicklime, etc. is poured into soft ground and mixed and stirred by a stirring blade to soft ground. The ground improvement method for improving the ground by curing the is well known in the art, and various stirring and mixing devices used in this method have been proposed.

As a method for discharging the slurry-like improving agent of these stirring and mixing apparatuses, a method is provided in which a discharge port is provided at the lower end of the stirring rotary shaft, and the improving agent is discharged and stirred and mixed only during penetration excavation, or a stirring rotary shaft. A modifier discharge port is provided above the lower end and above the stirring blade, and there is a method of mixing and stirring by discharging the improver from the lower discharge port when the rotary shaft penetrates and from the upper discharge port when withdrawing, but recently the latter The method is the mainstream.

Various types of devices for selecting the upper and lower discharge ports for discharging the slurry-like improving agent have been proposed. For example, in Japanese Patent Laid-Open No. 61-113923, a stirring rotary shaft is used. A method has been proposed in which a switching valve is provided in the hollow pipe and switching is performed by operating a manual hydraulic jack inside the hollow pipe and an automatic hydraulic jack provided at the top of the hollow pipe, but a complicated switching device and human operation are required. However, it is extremely troublesome, and there are many problems especially in the case of a deep mixing mixer having a depth of 10 to 30 m or more.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the above problems and discharges the slurry-like modifier with a simple structure depending on the rotating direction of the stirring rotary shaft at the time of penetration and withdrawal. The present invention proposes a modifier outlet switching device that can automatically switch to the upper outlet.

[0006]

That is, according to the present invention, improving agent discharge ports are provided at the lower end of an agitating rotary shaft having a slurry-like ground improving material supply pipe inserted in the axial center and above the uppermost stirring blade. In the deep-layer mixing agitator, a cylindrical valve body is supported horizontally and rotatably in the circumferential direction in the stirring rotary shaft at the above-mentioned upper discharge port position, and the valve body has an upper side of the improving agent depending on its rotation angle. A communication pipe that directly connects the supply pipe and the lower supply pipe, and a communication hole that communicates the upper supply pipe and the upper discharge port of the rotary shaft are provided, and the communication pipe has a height position substantially the same as that of the valve body of the rotary shaft. A swivel plate, which projects laterally and can swivel horizontally by earth pressure due to the rotation of the rotary shaft in soft soil, is pivotally supported, and the swivel plate swivels to coaxially fix the valve body through a wire. The pulley on the outside of the It relates the discharge port switching device modifiers in deep mixing agitator, characterized by comprising configured to drive a predetermined angular rotation of the valve member by Rukoto. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0007]

1 is an explanatory perspective view showing an embodiment in which a switching device according to the present invention is mounted on a stirring rotary shaft, and FIGS. 2 to 3 are cross-sectional views showing the action of a switching valve body. FIGS. 4 and 5 are bottom views showing the states of the swivel plate that rotationally drives the switching valve body when the stirring rotary shaft is inserted and withdrawn.

In the drawing, reference numeral 1 denotes a hollow tubular stirring rotary shaft in a deep-layer mixing and stirring apparatus, and the rotary shaft 1 has a plurality of radially multiple radial stages on the lower outer periphery thereof (for example, three vertical stages and two stages for each stage). Agitating blades 3 are attached, drilling blades (not shown) are provided on the outer periphery of the lower end, and a lower discharge port (not shown) of a slurry-like ground improvement agent such as cement slurry is further provided at the lower end of the shaft 1. Is provided, and an upper discharge port 20 for the improving agent is provided on the side surface of the rotating shaft 1 above the uppermost stirring blade 3.

Reference numeral 2 denotes an improving agent supply pipe which is inserted into the inner shaft of the stirring rotary shaft 1 and communicates with the lower discharge port or the upper discharge port 20 through a switching valve body 4 which will be described later. Is discharged into the surrounding soft ground.

Reference numeral 4 denotes the upper discharge port 20 in the stirring rotary shaft 1.
Is a cylindrical discharge port switching valve body that is inserted horizontally in a direction orthogonal to the improving agent supply pipe 2, and the valve body 4 is rotatably supported in its circumferential direction.

Reference numeral 5 is a straight pipe-shaped communication pipe having a vertical opening in the central portion of the valve body 4, and the communication pipe 5 is the supply pipe 3
The diameter of the upper supply pipe 2 is the same as that of the upper supply pipe 2 when the valve body 4 is rotated to match the upper supply pipe 2a.
The improving agent press-fitted into the inside of a is fed to the lower discharge port of the lower end of the rotary shaft 1 through the lower supply pipe 2b.

Reference numeral 6 denotes a communication hole formed in one side of the columnar valve body 4 at a position orthogonal to the communication pipe 5 and having a light hole. The communication hole 6 has the same diameter as the improving agent supply pipe 2, and the communication hole 6 is formed in the valve body. 4 communicates with an outlet 6b opened on the side of the upper discharge port 20 of the rotary shaft 1 through a space 6a formed around the communication pipe 5, and the communication is performed by rotating the valve body 4 in the circumferential direction. When the hole 6 coincides with the lower end of the upper supply pipe 2a, the improving agent press-fitted into the supply pipe 2a is discharged from the upper discharge port 20 through the outlet 6b, and the supply to the lower supply pipe 2b is blocked. It has a structure.

Reference numeral 7 denotes a pulley which is coaxially fixed to the valve rest 4 and is provided on the outer surface of the rotary shaft 1 on the side opposite to the upper discharge port 20 and is rotated by the horizontal rotation of the swivel plate 8.

Reference numeral 8 is a swivel plate mounted near the pulley 7 at a position substantially the same height as the valve body 4.
Is configured to project to the outside of the stirring rotary shaft 1 so as to be rotatable in the horizontal direction, and the base of the rotary plate 8 is a spindle supported by bearings 9, 9 having both upper and lower ends protruding from the outer surface of the rotary shaft 1. It is fixed to 10 and rotates horizontally with the support shaft 10 by a predetermined angle.

Reference numeral 11 denotes a pulley type wire fixing member which is coaxially fixed to the support shaft 10 and rotates together with the swivel plate 8. The pulling wire 12 having one end fixed to the member 11 has the other end on the outer peripheral surface of the pulley 7. The pulley 7 is rotated by the rotation of the member 11. Since the pulley 7 may rotate the valve body 4 by 90 ° in the circumferential direction, for example, the diameter ratio between the pulley 7 and the wire fixing member 11 is 2: 1.
In order to set the rotation angle of the fixing member 11 to 180 °, the stopper 1 is attached to the outer wall surface of the rotary shaft 1 on both left and right sides of the support shaft 10 of the swivel plate 8.
3, 13 are projected, and the horizontal turning range of the turning plate 8 is restricted to 180 ° by the stopper 13.

Therefore, when the stirring rotary shaft 1 is excavated and penetrated into the soft ground, the shaft 1 is rotated (counterclockwise in FIG. 1, clockwise in FIG. 4), and at this time, the pulley 7 is connected to the wire 12. Is wound around and the swivel plate 8 is brought into contact with the stopper 13a on the pulley 7 side, whereby the communication pipe 5 in the valve body 4 is aligned with the upper and lower improver supply pipes 2a, 2b to form a slurry state. The improving agent is a communicating pipe 5 and a lower connecting pipe 2
The improving agent is agitated and mixed with the surrounding soft soil by the agitating blade 3 so that the agent is discharged from the lower outlet of the lower end of the rotary shaft 1 via b (see FIGS. 2 and 4).

When the rotary shaft 1 reaches a predetermined depth, the rotary shaft 1 is pulled out while the shaft 1 is rotated in the reverse direction (clockwise in FIG. 1, and left in FIG. 5 when viewed from below). At this time, the swivel plate 8 is horizontally swung by the earth pressure toward the stopper 13b on the side opposite to the pulley 7, whereby the pulley type member 11 rotating integrally with the support shaft 10 of the swivel plate 8 is swung, The pulley 7 of the valve body 4 is rotated 90 ° via the wire 12. As a result, the valve body 4 rotates 90 ° in the circumferential direction together with the pulley 7, and the communication hole 6 of the valve body 4 that communicates with the upper discharge port 20 of the rotary shaft 1.
Is communicated with the lower end of the upper supply pipe 2a of the improver, and the improver is discharged from the upper discharge port 20 without flowing to the lower supply pipe 2b, and the stirring blade 3 again performs stirring and mixing. .

[0018]

The improving agent discharge port switching device according to the present invention is configured as described above, and is capable of driving a swiveling plate that horizontally swivels due to earth pressure depending on the rotational directions when the stirring rotary shaft is inserted and withdrawn. By rotating the valve body in its circumferential direction, it is possible to automatically switch the discharge of the slurry-like improving agent to the lower discharge port or the upper discharge port.
It has advantages such as reliable operation, simple structure, and easy manufacture.

[Brief description of the drawings]

FIG. 1 is an explanatory perspective view showing an example of a state in which an improving agent discharge port switching device according to the present invention is attached to a stirring rotary shaft.

FIG. 2 is a cross-sectional view showing a state of the valve body according to the present invention when the stirring rotary shaft penetrates.

FIG. 3 is a cross-sectional view showing a state when the stirring rotary shaft of the valve body is pulled out in the present invention.

FIG. 4 is a bottom view showing a state of the swivel plate when the stirring rotary shaft penetrates.

FIG. 5 is a bottom view showing a state of the swivel plate when the stirring rotary shaft is pulled out.

[Explanation of symbols]

 1-stirring rotary shaft 2-slurry conditioner supply pipe 3-uppermost stirring blade 4-switching valve body 5-communication pipe 6-communication hole 7-pulley 8-slewing plate 9-bearing 10-spindle 11-wire Fixing member 12-Wire 13-Stopper 20-Upper discharge port

Claims (1)

[Claims] 1. A deep-layer mixing agitator in which a improving agent discharge port is provided above the lower end of a stirring rotary shaft and the uppermost stirring blade in which a slurry-like ground improvement material supply pipe is inserted in the axial center, and the above-mentioned upper side is provided. A cylindrical valve body is supported horizontally and rotatably in the circumferential direction in the stirring rotary shaft at the discharge port position, and the valve body is provided with an upper supply pipe and a lower supply pipe of the improving agent depending on the rotation angle. A communication pipe for direct communication and a communication hole for communicating the upper supply pipe with the upper discharge port of the rotary shaft are provided, and the rotary shaft protrudes laterally outside the valve body at substantially the same height as the valve body. A swivel plate that can swivel horizontally is pivotally supported by the earth pressure due to the rotation of the shaft in soft soil, and the swivel plate swivels the pulley outside the rotary shaft that is coaxially fixed to the valve body via a wire. Move the valve body to the desired position by moving it A modifier outlet switching device in a deep-layer mixing agitator, which is configured to be driven to rotate at an angle.