JPS64426Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a plate for preventing paper drain material from rising.

Conventionally, a paper drain material made of highly permeable non-woven fabric formed into a belt is cast vertically into soft ground, and a large amount of water contained in the ground is collected by this drain material and drawn up to the ground surface due to its water permeability. The so-called OV drain method is generally known, which promotes ground subsidence early and increases the strength of the ground. The drain installation machine used in this OV drain construction method has a structure in which the drain material is inserted vertically through the interior of the mandrel that is placed underground, and its lower end is held at the tip of the mandrel. After the mandrel is placed, when it is pulled up, the lower end of the drain material remains underground, and as a result, the drain material remains underground.

As shown in FIG. 1, the conventional drain material leaving means for realizing the above-mentioned effect includes a corrugated plate 4 that winds up the excess end of the drain 3 protruding from the lower end of the central groove 1a of the mandrel 1; The corrugated plate 4 is combined with a support plate 5 that presses the lower end of the corrugated plate 4, and the plates 4 and 5 are superimposed on the tip of the mandrel 1.

However, in the case of a combination of these plates 4 and 5, it is necessary to hold the plates 4 and 5 by hand so that they overlap in the flat shape shown in the figure until the mandrel 1 touches the ground surface, and each Settings are troublesome.

In addition, when the mandrel 1 is lowered into the ground, if the earth pressure at the tip is not applied uniformly to the plate 5 and is omnipresent, there is a risk that the plates 4 and 5 may shift and come off from the tip of the mandrel 1. .

Furthermore, when the mandrel 1 is pulled up after being placed, there is some play before the anchoring effect is activated due to the earth pressure applied to the plates 4 and 5, and this causes the drain material 3 to move up as the mandrel 1 rises by the amount of play. Various problems were pointed out, such as the fact that the drain material sometimes rises and remains underground for a length shorter than the set depth, and that a large amount of drain material 3 is required.

This invention was made to solve the above-mentioned problems, and its purpose is to be able to attach it to the tip of the mandrel with one touch, to prevent it from shifting during pouring, and to be able to attach it to the tip of the mandrel with a single touch. To provide a plate for preventing paper drain material from being dragged up, which has an immediate anchoring effect and allows the drain material to remain in the soil.

Hereinafter, one embodiment of this invention will be described in detail using the drawings from FIG. 2 onwards.

FIG. 2 shows the tailing prevention plate 10 according to this invention. This prevention plate 10 is made of an elastic plastic injection molded body, and includes a flat plate part 12 attached to the lower end of the mandrel 1, and a slit 14 formed in the center of the flat plate part 12 along its longitudinal direction. , a pair of guide plates 16, 16 integrally provided vertically along both sides of the slit 14 on the bottom surface of the flat plate portion 12;
and hinge parts 18 on both sides of the flat plate part 12,
18, and a pair of anchor vanes 20, 20 extending in the same plane.

A slit 14 is provided in the upper part of the flat plate part 12.
A pair of tapered guide blocks 22, 22 whose diameter increases upward is formed on both sides of the mandrel, and the paper drain material 3 protruding from the lower end of the mandrel 1 is guided by the guide blocks 22 as shown in arrow A.
direction into the slit 14. However,
If a pair of guide plates 16, 16 are sandwiched together using metal stitchers, etc., both guide plates 16, 16 will be elastically deformed and the drain material 3
is fixed between the two via the metal stitcher, and at the same time the slit 14 is closed.

Further, the hinge portion 18 is a groove-shaped member called a plastic hinge, and the anchor vane 20 rotates in the direction of arrow B only when an upward force is applied from a horizontal state.

Furthermore, two serrated locking pawls 26, 26, which are rotatable only in the direction of arrow B, are integrated along the longitudinal direction at the tip of each anchor vane 20 via second hinges 24, 24. It is formed.

FIG. 3 shows a state in which the drag prevention plate 10 constructed as described above is attached to the tip of the mandrel 1, and the drain material 3 is fixed with a metal stitcher 28.

In this embodiment, tapered notches 1b are formed on both sides of the outer peripheral portion of the lower end of the mandrel 1. Correspondingly, the flat plate portion 12 of the prevention plate 10 is set to have an area equal to the lower end surface of the mandrel 1, and the anchor vane 20 is set to have an area equal to the area of the notch portion 1b.

Therefore _, when the mandrel 1 is driven in the direction of the arrow C as shown in FIG.
rotates about the hinge portion 18 as a reference point, as shown by the imaginary line in the figure, and approaches the notch portion 1b of the mandrel 1. In addition, as a result of the locking claw portion 26 at the tip further rotating about the second hinge portion 24, the mandrel 1
Extends horizontally and abuts linearly on the outer periphery of. The higher the earth pressure when the mandrel 1 is pushed, the greater the tangential stress becomes. Therefore, mud flow such as sludge does not enter the mandrel 1, and the vanes 20 and the locking claws 26 are attached to the outer periphery of the mandrel 1. By adhering it, it will not fall off during pouring.

Next, when the mandrel 1 is pulled up from the ground in the opposite direction to the arrow C, an earth pressure P ₂ in the opposite direction is applied to the prevention plate 10, and the earth and sand are moved between the locking claw part 26 and the outer periphery of the mandrel. As a result, the vane 20 and the locking pawl 26 return to their flat state. Therefore, when the drain material 3 is flattened in this way, the resistance against the drain material 3 becomes extremely large, and as a result, the tip of the drain material 3 is reliably left underground.

As explained above, the drag-up prevention plate according to this invention can be attached to the tip of the paper drain material with one touch, and when a mandrel is placed, it remains securely located at the tip of the mandrel. Not only does it not create resistance during installation, it also prevents mudflow from entering the mandrel. Also, when the mandrel is pulled up, its anchor vanes immediately flatten, creating a large amount of resistance.
The drain material does not rise along with the mandrel, and can be reliably left at a predetermined depth underground.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a main part showing a conventional drain material leaving means, Fig. 2 is an exploded perspective view of a back-up prevention plate according to this invention, and Figs. 3 1 and 2 are the tip of a mandrel provided with the same prevention plate. FIG. DESCRIPTION OF SYMBOLS 1... Mandrel, 3... Paper drain material, 10... Entrainment prevention plate, 12... Flat plate part, 14... Slit, 16... Guide plate, 20
...Anchor vane, 24...Latching claw portion, 28...
...Metal stitching.

Claims (1)

[Scope of utility model registration request] A flat plate attached to the lower end of the mandrel, a pair of guide plates on both sides of a slit formed in the center of the flat plate and hanging from the bottom of the flat plate, and a pair of guide plates on both sides of the flat plate. A pair of anchor vanes that are integrated and elastically deform toward the outer periphery of the mandrel when the mandrel is cast; and a plurality of horizontally extending strips at the ends of each anchor vane that abut the outer periphery of the mandrel during the elastic deformation. A paper drain material consisting of a serrated locking claw part and protruding from the lower end of the mandrel is inserted into the slit, and the lower end of the paper drain material is fixed by sandwiching both the guide plates, and at the same time, the slit is closed. A plate for preventing paper drain material from accumulating.