JP2000328864A - Expandable-diameter bit for drilling, for constructing concrete pile for use in reinforcing concrete bedrock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expandable-diameter bit for drilling, which facilitates formation of a hole in which a concrete pile for strengthening bearing capacity of a concrete bedrock is driven, in the ground. SOLUTION: The expandable-diameter bit 1 for drilling, for constructing a concrete bedrock reinforcing concrete pile, has a high-pressure water guiding hole 21 formed therein, and is made up of a bit base body 2 having an excavating portion at one end, and an expandable- diameter blade 4 which is pivotally mounted on the bit base body 2 and capable of laterally expanding. The bit base body 2 is forwards or backward rotated by a rotary rod 6 having the high-pressure guiding hole 21 formed therein, and therefore the excavating portion or the expandable-diameter blade 4 expanded together with the excavating portion is activated, to thereby bore an excavated hole with one of a variety of cross sections. Further, the bit base body 2 has a notch portion 25 formed in a side portion thereof, for pivotally mounting the expandable-diameter blade 4 in the notch portion 25, whereby the expandable-diameter blade 4 can be rotated between a position in which the blade 4 is housed in the notch portion 25 and a position in which the blade 4 protrudes from the notch portion 25. Still further, the external diameter of the bit base body 2 is made smaller than the external diameter of the excavating portion formed at the one end thereof, whereby the expandable-diameter blade 4 can easily protrude from the notch portion 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling bit for constructing a concrete pile for reinforcing a concrete base placed in a tunnel or a building for running a train.

[0002]

2. Description of the Related Art In general, concrete bases are cast in train running tunnels in order to obtain stable running regardless of speed on a track on which a heavy load train is laid. The cast concrete base is deformed by natural ground phenomena such as earthquakes and springs, and the soil is crushed due to vibrations during train operation. Becomes unstable, and the deformation of the concrete base is enhanced by the repeated running of the train, so that the running of the train becomes more and more unstable. In addition, concrete foundations are also cast in the construction of buildings, but again, concrete bases may be deformed due to burial of the ground, causing the buildings to tilt and fall down.

[0003] In recent years, emergency treatment means have been developed in which a concrete pile integrated with a concrete base is driven into the ground to prevent the deformation of the existing concrete base from increasing.

In such a conventional emergency treatment means, after drilling a required portion of an existing concrete base, the ground is cylindrically drilled through a bit of a drilling machine through the drilled portion, and the drilled portion and the ground are drilled. Concrete is poured into the perforated portion to construct a concrete pile. The constructed concrete pile has an upper end near the perforated portion of the concrete base integrally joined to support the concrete base, and has a supporting force exceeding a diameter range which is at least one element of the concrete pile. When it is not possible to obtain, and for example, to change the size of the diameter of the concrete pile according to the magnitude of the earth bearing capacity, select a bit with a different diameter of rotation and attach it, drilling the ground Become.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a concrete pile driving hole capable of increasing the supporting force of a concrete base. Another object of the present invention is to provide a drill bit for drilling which can be easily formed.

[0006]

In order to achieve the above object,
According to the first aspect of the present invention, there is provided an enlarged diameter drilling bit for constructing a concrete pile for reinforcing a concrete base, wherein a high-pressure water guide hole is formed, and one end of the drill bit is a digging portion. The bit base is rotated forward or backward by a rotating rod having a guide hole for high-pressure water, and is operated by the excavating unit or the excavation. The construction of a concrete pile with a drilling bit with various cross-sections formed by the operation of the expanding blade that expands with the part to achieve multiple functions with one drilling bit. The drilling bit for constructing a concrete pile for reinforcing a concrete base according to claim 2 of the present invention is characterized in that the cost is reduced. On the side of A notch is formed, and a large-diameter blade is pivotally supported in the notch so that the large-diameter blade is rotatable between a position stored in the notch and a position protruding from the notch. When drilling by operating the excavation part provided in
It is characterized in that the enlarged diameter blade is housed in the notch so as not to unnecessarily drill. The drilling bit for constructing a concrete pile for reinforcing a concrete base according to claim 3 of the present invention is the drilling bit for drilling according to claim 1 or 2, wherein the outer diameter of the bit base is one end. The diameter is made smaller than the outer diameter of the digging part provided in the horn, and the enlarged blade can easily protrude from the inside of the notch.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a concrete pile for reinforcing a concrete base according to the present invention.

FIG. 1 is a cross-sectional view of a drilling bit 1 according to an embodiment of the present invention.
Is a bit base 2, a tip blade 3, 3 having an outer diameter larger than the outer diameter of the bit base 2, and a pair of enlarged blades 4 pivotally supported so as to be housed and protrudable on the side of the bit base 2. 4 and a nozzle 5 and are connected to a pivot rod 6 (see a dashed line) by a bolt 7. In these constituent members, the bit base 2 includes a guide hole 21 for high-pressure water penetrating the center, a recessed portion 23 in which a center end portion 22 is hollowed out, and a thick portion 24 having a diameter larger than that of the end portion 22.
Two notched portions 25, 25 formed by hollowing out side portions of the notched portions, and two pin installation holes 26, 26 having a length exceeding the thickness of the notched portions 25, 25 in the two notched portions 25, 25; Bolt installation holes 28, 28 are formed in the rear end 27,
The tip blades 3, 3 are welded to the tip 22 of the bit base 2, and a number of carbide tips 31,
31 is fixed, and the bit base is made smaller in diameter than the outer diameter of the excavated portion composed of the tip blade pieces 3, 3 so that the enlarged blade can easily protrude from the notch. On the other hand, the diameter-enlarged blades 4, 4 on which the carbide tips are fixed, are positioned in the notches 25, 25 formed on the side of the bit base 2 and the cutting edges of the diameter-enlarged blades 4, 4. Are pivotally supported by pins 8 so as to be rotatable between positions protruding from the notches 25, 25 and abutting against inner walls of the notches 25, 25. The second high pressure water guide hole 21 is fixedly provided in the concave portion 23 of the second end portion 22.

The drilling bit 1 having the above-described structure is configured to inject high-pressure water from the nozzle 5 through a rotating rod (see a dashed line) 6 and to use a positive drive by a driving device. Both the rotation and the depression are transmitted and actuated, and a hole for a concrete pile is excavated and formed in the ground while excavating the excavated soil by the tip blades 3 and 3 with high-pressure water. Then, in order to form a large-diameter concrete pile or a flanged concrete pile in order to enhance the supporting force of the existing concrete base, the drilling bit 1 is reversely rotated. Due to the centrifugal force generated by the reverse rotation, the diameter-enlarging blades 4 drill holes while expanding in the direction perpendicular to the bit base 2 with the pin 8 as a fulcrum (see a two-dot chain line portion). Since high-pressure water for excavation and soil removal acts near the radial blades 4 and 4, excavated soil entering the vicinity of the pivot pin 8 is constantly discharged into the borehole, and the diameter of the enlarged blades 4 and 4 is reduced. There is no hindrance to the free spreading action. In addition, the said diameter expansion blades 4 and 4
Although the structure may be simply supported on the peripheral surface of the bit base 2 having a small diameter, in the present embodiment, as described above, particularly, the enlarged diameter blades 4, 4 are hollowed out from the side of the thick portion 24. The structure supported by the formed notch portion 25 is adopted, and the thick portion 2
In the retracted state where the enlarged diameter blades 4 do not bulge from 4, the smooth operation of the excavation by the tip blade pieces 3, 3 can be achieved, and the supporting force of the enlarged diameter blades 4, 4 is enhanced. You will get.

FIG. 2 is a sectional view taken along the line AA of the diameter-enlarged bit 1 for drilling shown in FIG. 1, and the bit base 2 has a diameter-enlarged blade 4 on which carbide tips 41, 41 are fixed. , Storing 4
Notches 25, 25 are formed,
4 is a pin 8, 8 implanted in two pin installation holes 26, 26
The cutting edges of the enlarged blades 4, 4 are pivotally supported by the notches 25, 25 from the storage positions in the notches 25, 25 (see the solid lines).
5 and can be expanded to an enlarged diameter position (see a two-dot chain line portion) that abuts against the inner wall 251 of the notches 25, 25. When drilling by operating a digging part provided at one end of the bit base, an enlarged blade is stored in the notch portion 25, 25 so that the enlarged blade does not perform a drilling operation unnecessarily. I do. A high-pressure water guide hole 21 is provided at the center of the bit base 2 for excavation and earth removal, and supplies high-pressure water.

FIG. 3 illustrates a construction method for constructing, for example, a concrete pile having a flange at an upper end portion on the ground under the existing concrete base B by the drilling bit 1 shown in FIG. It is a figure, the 1st process which opens the existing concrete base B, the 2nd process which excavates the diameter expansion hole 10 in the ground part near the lower surface of the existing concrete base B, and the diameter smaller than the diameter expansion hole 10 A third step C for excavating the hole 11 for the pile base and a fourth step D for charging the concrete 12 into the hole excavated and formed into a required shape.

Here, the construction of a flanged concrete pile will be described with reference to the above-mentioned process diagrams (a) to (d).

First, in the first step (a), a core drill C is installed at a predetermined position on an existing concrete base B via a supporting rod D, and the core drill C is driven to remove a cylindrical casing tube C1. Rotate. And handle C2
Is turned on to act on the existing concrete base B while pushing down the casing tube C1, the hole is drilled by the bit C3 provided at the tip of the casing tube C1, and the penetration hole B1 for inserting the drilling bit is inserted. Is formed.

Next, the process proceeds to the second step (b), and an enlarged hole 10 corresponding to the flange of the flanged concrete pile is excavated. At the time of this excavation, for example, a drilling machine G is installed in advance so as to be vertically movable on a support rod F supported by an arm tip E such as a backhoe, and a hole is formed in a penetration hole B1 of an existing concrete base B in advance. After penetrating the cover B2, the muddy water discharge hose B3 is inserted and placed. The bearing rod F is provided with a guide F1 for the rotating rod 6 and a guide F2 for moving the drilling machine G up and down. The drilling machine G is provided with a drilling drill shown in FIG. A diameter bit 1 is connected to one end, and the other end is provided with a water swivel H with a water supply hose H2 via a swivel coupling H1. And a rod driving device I for driving the motor. After such preparation, the drill driving bit I is started by inserting the drill bit 1 into the penetrating hole B1, and the high pressure water from the water swivel H with the water supply hose H2 is discharged. The drilling bit 1 is rotated forward and down until the expanding blades 4 and 4 of the drilling bit 1 reach the lower surface B1 of the existing concrete base B while being sprayed from the tip of the drill bit 1. Drill the ground J. Here, when the drilling bit 1 is rotated in reverse while the injection of high-pressure water is maintained, the expanding blades 4 and 4 provided in the drilling bit 1 are expanded by centrifugal force, and the drilling hole is enlarged. When the hole 10 is to be excavated and the thickness of the diameter-enlarged hole 10 is to be increased, the diameter-enlarged bit 1 for drilling may be pushed down to a required depth while rotating in the reverse direction. The mud generated at the time of drilling is discharged by a mud discharge hose B3.

Subsequently, the process proceeds to a third step c, where the hole 11 for the pile base of the concrete pile with flange is excavated. In this excavation, high pressure water from water swivel H is injected from the tip of the drilling bit 1, and the drill J is rotated forward and down by driving the rod driving device I, and the ground J is required. Drill to the depth and finish.

After forming the desired flanged concrete pile hole 9 through each of these excavation steps A, B and C, the bearing rod F, the drilling machine G, the backhoe and the like are removed, and the process proceeds to the fourth step D. Then, the concrete 12 is put into the hole 9 for the flanged concrete pile. When the concrete 12 is loaded, for example, a loading tool K composed of a hopper K1 and a hose K2 is suspended by a crane M via a holding tool L at a predetermined position on the existing concrete base B. Then, the holder L is moved by the operation of the crane M, and the hose K2 connected to the hopper K1 is inserted until the hose K2 reaches the vicinity of the bottom of the hole 9 for the flanged concrete pile.
Crane M while supplying concrete to hopper K1
To raise the loading tool K until the end of the hose K2 reaches the lower surface of the existing concrete base B.

In each of these steps, a flanged concrete pile N capable of strongly supporting and reinforcing the existing concrete base B is cast and formed, and the drilling bit 1 for drilling according to the present invention is used. Various shapes of concrete piles can be cast and formed. For example, in the case of constructing a multi-stage flanged concrete pile capable of obtaining a larger ground strength, each of the enlarged holes 10 and 10 corresponding to the flange of the flanged concrete pile as shown in FIG. The drilling bit 4 is rotated in the reverse direction to excavate while expanding the diameter-enlarging blades 4, 4, while the hole 11, 11 for the pile base having a smaller diameter than the diameter-expanding holes 10, 10 is excavated. In the case of drilling and forming a flanged concrete pile hole 13 by rotating the drilling bit 1 in the forward direction and operating only the tip blade 3 for each part, and constructing a concrete pile having a different thickness. For example, as shown in FIG. 5, as shown in FIG. 5, a hole 14 for a small-diameter concrete pile is excavated and formed by rotating the drilling bit 1 in the normal direction and only the tip blade 3 is operated. The enlarged diameter blades 4 and 4 are expanded by rotating the enlarged diameter bit 1 in the reverse direction. It is to boring forming a large diameter concrete pile hole 15 Te.

In each of the above-mentioned steps, in particular, in the step of excavating and forming a hole for a concrete pile, only the diameter-enlargement bit for a drill according to the present invention is applied, so that a drill bit for which preparation is required is prepared. The number of types is reduced, and the work of selecting and replacing various drilling bits for a drilling machine is also eased, so that cost reduction and workability are improved.

As described above, each embodiment of the present invention has been described in detail. However, the present invention is not limited to the above-described embodiment, and may be designed without departing from the spirit of the present invention described in the appended claims. Various changes can be made. For example, although the description has been given of the case where the diameter-enlarging bit is two in the drilling-diameter expanding bit of the present invention, the number of diameter-expanding blades can be changed in design.

[0020]

As can be understood from the above description, the drilling bit for constructing a concrete pile for reinforcing a concrete base according to the present invention is constructed such that the diameter-enlarging blade is pivotally supported so as to be able to expand in addition to the tip blade. Both are equipped with a guide hole for high-pressure water, and only vertical movement and forward / reverse rotation are performed via a rotating rod by the rod driving device of the drilling machine, and at the same time, high-pressure water is ejected to facilitate excavation. The drilling of various cross-sectional shapes is achieved, and high pressure water prevents earth and sand clogging in the vicinity of the expanding blade, thereby maintaining the expandability of the expanding blade. The performance has been improved.

[Brief description of the drawings]

FIG. 1 is a side view of an enlarged bit for drilling which is an example of the present embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of the diameter-enlarged bit for drilling shown in FIG. 1;

FIG. 3 is an explanatory view of a construction method for constructing a flanged concrete pile with the drilling bit shown in FIG. 1;

FIG. 4 is an explanatory diagram relating to a flanged concrete pile hole different from the configuration shown in FIG. 3;

FIG. 5 is an explanatory view of forming a concrete pile hole having a small diameter or a large diameter different from the shapes shown in FIGS. 3 and 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Diameter expansion bit 2 Bit base 3 Tip blade 4 Diameter expansion blade 5 Nozzle 6 Rotating rod 7 Bolt 8 Pin 9, 13, 14, 15 Concrete pile hole 10 Diameter hole 11 Pile base hole 12 Concrete _

Continued on the front page (72) Inventor Shuji Tomita 2-2-2 Yoyogi, Shibuya-ku, Tokyo East Japan Railway Company (72) Inventor Yoshinori Matsuda 2-2-2 Yoyogi, Shibuya-ku, Tokyo Tohnichi Inside the Japan Railway Company (72) Inventor Tomoaki Moriyama 2-2-2 Yoyogi, Shibuya-ku, Tokyo East Japan Inside the Japan Railway Company (72) Inventor Kazuhiko Koyama 2-chome, Ichigaya-Sadohara-cho, Shinjuku-ku, Tokyo (72) Inventor Takashi Kitamura 2-7-7 Ichigaya-Sadohara-cho, Shinjuku-ku, Tokyo

Claims (3)

[Claims] A high pressure water guide hole is formed, and one end includes a bit base as an excavation part, and a diameter expanding blade pivotally supported by the bit base and capable of expanding laterally. By rotating the bit base forward or backward by a rotating rod provided with a guide hole for the operation, the excavating part or the expanding blade that expands with the excavating part is operated, and the drilling holes of various cross-sectional shapes are formed. A drill bit for drilling a hole for constructing a concrete pile for reinforcing a concrete base, characterized by forming a hole. 2. A notch is formed on a side of a bit base,
2. The enlarged diameter blade is pivotally supported in the notch portion so as to be rotatable between a position where the enlarged diameter blade is stored in the notch portion and a position where the enlarged diameter blade protrudes from the notch portion. A drill bit for drilling a hole to build a concrete pile for reinforcing a concrete base. 3. The bit body according to claim 1, wherein the outer diameter of the bit base is smaller than the outer diameter of the excavated portion provided at one end.
A diameter drilling bit for drilling a concrete pile for reinforcing a concrete base according to claim 2.