JP2008008073A - Kneaded earth and sand accompanying rotation preventive apparatus for drilling/stirring rod - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent accompanying rotation of kneaded earth and sand by keeping an accompanying rotation preventive blade in a static state during a stirring operation without adopting a configuration in which the front end of the accompanying rotation preventive blade is caused to cut into the peripheral ground in a shaft. <P>SOLUTION: According to a kneaded earth and sand accompanying rotation preventive apparatus for a drilling/stirring rod, the drilling/stirring rod includes a drilling head on the lower end of the rod, and a plurality of stages of projecting stirring blades on the rod outer peripheral surface above the drilling head. Between stirring blades vertically adjacent to each other or between the drilling head and a stirring blade, the base of the accompanying rotation preventive blade is supported rotatably on the rod while the front end portion of the blade is extended radially, where a contact pressure plate, whose surface is to be kept in pressure contact by spring with the interior surface of a circular shaft to be drilled by the drilling head, is attached to the front extremity of the accompanying rotation preventive blade. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  In the excavation stirring rod used for ground improvement, in particular, its deep stirring mixing method and various other applications, the present invention prevents the stirring and kneading soil of the drilling earth and hardening liquid from rotating (corotating) together with the stirring blades, etc. Thus, the present invention relates to a kneading earth and sand co-rotation prevention device for performing sufficient mixing.

  Conventionally, for example, in an excavation stirring rod for ground improvement in which a drilling head is provided at the lower end of the rod and a plurality of stirrer blades are provided on the outer circumferential surface of the upper rod, The anti-rotation blade having a diameter larger than the excavation diameter of the excavation head is rotatably supported with respect to the rod, and in use, the rod is rotated and the excavation head excavates a circular vertical hole in the ground, and the lower end of the rod The cement milk and the excavated earth and sand are agitated and mixed by the agitating blade, and the co-rotation preventing wing penetrates the tip of the surrounding ground and is in a stationary state. Even if the kneaded soil with milk tries to rotate together with the stirring blade, it is prevented from co-rotation by the co-rotation preventing blade and forcibly crushed, thereby further effectively stirring and mixing. What has been proposed.

However, in the above-mentioned conventional device, the tip portion of the co-rotation preventing wing must be penetrated into the ground around the vertical hole, and the tip portion of the co-rotation preventing wing is inserted into the surrounding ground from the start of excavation to the advance to a predetermined depth. Therefore, there is a drawback that the above penetration or descent becomes difficult when hitting an obstacle in the ground. In particular, when the surrounding ground is a hardened ground whose ground improvement has been completed, the above-mentioned drawbacks are fatal, and there is a risk of causing damage to the apparatus when forcibly excavating.
Japanese Patent No. 1197295

  The present invention does not take a configuration in which the tip portion of the co-rotation preventing wing penetrates into the surrounding ground of the vertical hole, and keeps the co-rotation preventing wing stationary when stirring, thereby preventing co-rotation of the kneaded earth and sand. It is an object of the present invention to provide a kneading earth and sand co-rotation prevention device that can be used.

As a means for achieving the above object, the present invention provides:
In the excavation agitation rod in which the excavation head is provided at the lower end of the rod and the agitation blades are provided in a plurality of stages on the outer peripheral surface of the upper rod,
Between the stirring blades adjacent to each other in the vertical direction or between the excavation head and the stirring blades, the base of the co-rotation prevention blade is rotatably supported by the rod, and the blade tip extends radially,
At the tip of the co-rotation prevention wing, a pressure contact plate to be always pressed with a plate surface by a spring on the inner surface of the circular vertical hole to be drilled by the excavation head,
Proposal is made of a kneading and sediment co-rotation prevention device for excavation stirring rods.

  According to the kneading earth and sand co-rotation prevention device of the excavation agitation rod of the present invention, the pressure-contacting plate is brought into pressure contact with the inner surface of the circular vertical hole excavated by the excavation head by the plate surface. Can be held in a stationary state, thereby preventing co-rotation of the kneaded earth and sand, and crushing the kneaded earth and sand between the rotating stirring blade and the stationary anti-rotation blade in a stationary state, and sufficient stirring and mixing. It can be carried out.

  In addition, while continuing the excavation from the start of excavation, the pressure contact plate at the tip of the co-rotation prevention blade is lowered while being pressed against the inner surface of the vertical hole by a spring, so that it will not hit an obstacle in the ground. In addition, even if there is an obstacle projection on the inner surface of the vertical hole, the pressure contact plate can be elastically displaced and smoothly lowered, thereby eliminating the risk of causing damage to the apparatus.

Embodiments of the present invention will be described in detail below with reference to the drawings.
The excavation agitation rod (1) of FIG. 1 has an excavation head (3) composed of two excavation blades at the lower end of a hollow rod main body (2), and a radial direction on the outer peripheral surface of the upper rod main body (2). Two sets of two stirring blades (4), (4), (4), and (4) that extend are respectively provided in two upper and lower stages with an appropriate vertical spacing, and these two stirring blades ( 4) Between (4), (4) and (4), the co-rotation preventing wings (5) and (5) are rotatably supported by the rod body (2).

  The structure of the co-rotation preventing wings (5) and (5) is as follows. A pair of flanges (6) and (6) are fixed to the outer peripheral surface of the rod body (2) between the two-stage stirring blades (4), (4) and (4), (4) with an appropriate vertical spacing. Then, a concave annular boss receiving part (7) is formed between the flanges (6) and (6), and the annular boss (9) is rotated to the boss receiving part (7) via the bush (8). The boss (9) is fitted freely, and two co-rotation prevention blades (5) and (5) are radially projected from the outer peripheral surface of the boss (9) at equal angular intervals.

  The co-rotation preventing wings (5) and (5) have an elastically expandable structure. When one of them (5) is viewed, the outer peripheral surface of the annular boss (9) as shown in FIG. In addition, an approximately square cylindrical cylinder (10) is projected, and an approximately square columnar arm (11) having a pressure contact plate (12) at the tip thereof is axially slidable and non-rotatable on the cylinder (10). While being inserted, the arm (11) is constantly ejected in the radial direction by a spring (13) built in the cylinder (10).

  Further, the pin (14) is penetrated through the arm (11) in the transverse direction, and both end portions of the pin (14) are elongated in the longitudinal direction (15) provided in the peripheral wall of the cylinder (10). ) And (15) are slidably engaged so that the arm (11) can advance and retreat within the length range of the long holes (15) and (15).

  In this case, when the arm (11) is retracted to the last position against the spring (13), the pressure contact plate (12) is a circular vertical hole (H) excavated by the excavation head (3) (FIG. 1 (b)) is in contact with or away from the inner surface, and when the arm (11) is ejected by the spring (13) and advanced to the foremost position, the pressure contact plate (12) is It is designed to reach a position protruding slightly outward from the inner surface of the vertical hole (H).

  In order to make the press contact plate (12) ascend and descend in a state where it is pressed against the inner surface of the vertical hole (H), as shown in FIGS. 1 (a) and 2, the upper and lower ends of the press contact plate (12). In addition, inclined guide plates (16) and (16) which are slightly inclined inward are provided in series.

  (17) is an agitation auxiliary plate fixed to the outer surface of the cylinder (10), with the plate surface facing the rotation direction of the excavation agitation rod (1).

  The other co-rotation preventing wing (5) has the same structure as described above. A curable liquid supply pipe is vertically passed through the hollow rod body (2), and a curable liquid discharge port is provided at the lower end of the rod body (2).

  The operation of the above example will be described next. The excavation agitation rod (1) is rotated, and the excavation head (3) excavates a circular vertical hole (H) in the ground while pressing the rod into the vertical hole (H). As it is discharged into the hole, the excavated sediment and cement milk are stirred and kneaded by the rotating stirring blade (4), and further, the upper and lower stirring blades (4), (4), (4), (4) The co-rotation preventing wings (5) and (5) in between are pressed against the inner surface of the vertical hole (H) by the resilient force of the springs (13) and (13) with the pressure contact plates (12) and (12) at the tip thereof. The co-rotating blades (5), (5), which are kept stationary and thereby stationary, and the rotating stirring blades (4), (4), (4), (4) together In addition, the kneaded earth and sand are crushed, and they combine to thoroughly mix the earth and cement milk. To form a cement.

  After forming the soil cement, the excavation stirring rod (1) is pulled out.

  In the excavation and extraction of the excavation stirring rod (1), the pressure contact plates (12) and (12) of the co-rotation prevention blades (5) and (5) are in pressure contact with the inner surface of the vertical hole (H). The vehicle can travel without receiving excessive friction load. In addition, the inclined guide plates (16)... Smoothly guide the travel of the pressure contact plates (12) and (12) to facilitate raising and lowering.

  In the travel of the pressure contact plates (12), (12), when there are obstacle projections on the inner surface of the vertical hole (H), the pressure contact plates (12), ( Due to the elastic displacement by the springs (13) and (13) of 12), the protrusion can be easily pasted.

(A) It is a partially omitted front view of the excavation stirring rod provided with the co-rotation preventing device according to the present invention. (B) (A) It is an AA line sectional view of a figure. It is an enlarged vertical front view of a co-rotation preventing wing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Excavation stirring rod 2 Rod body 3 Excavation head 4 Stirring blade 5 Co-rotation prevention blade 12 Pressure welding plate 13 Spring H Vertical hole

Claims (1)

In the excavation agitation rod in which the excavation head is provided at the lower end of the rod and the agitation blades are provided in a plurality of stages on the outer peripheral surface of the upper rod,
Between the stirring blades adjacent to each other in the vertical direction or between the excavation head and the stirring blades, the base of the co-rotation prevention blade is rotatably supported by the rod, and the blade tip extends radially,
At the tip of the co-rotation prevention wing, a pressure contact plate to be always pressed with a plate surface by a spring on the inner surface of the circular vertical hole to be drilled by the excavation head,
A device to prevent co-rotation of the excavation and stirring rod.

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