JP3193985B2 - Boring rod - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boring rod for efficiently drilling a hole such as an underground hole, an anchor hole, a buried pipe drilling in the ground, the ground, a slope, etc. in civil engineering construction work. .

[0002]

2. Description of the Related Art Conventionally, a boring rod provided with a slime discharge path in a state in which water or air is contained in excavated rocks or excavated pieces of excavated rock or ground has an inner cylinder inserted into an outer cylinder, and Double pipe structure with space for slime discharge between outer cylinder and inner cylinder, bit is connected to lower end of inner cylinder, and outer peripheral surface of bit is elongated in the vertical direction and recessed to almost uniform width This is a structure in which a discharge path is formed. Conventionally, high-pressure drilling water or air is injected into the drilling hole during drilling with a boring rod, so slime is under pressure. It is discharged into the space between the inner cylinder and discharged directly to the ground. However, the width of the discharge path is almost uniform, and the slime extruded into the discharge path is subject to greater resistance as it progresses to the rear of the discharge path. And there is a problem that the excavation is hindered. In addition, the size of excavated stones and excavated pieces contained in the slime also varies, and when excavated stones or excavated pieces of a size that are difficult to pass through the discharge path enter the discharge path, the speed of slime discharge is reduced, and the excavation efficiency is reduced. There is a problem that it decreases.

[0003]

The problem to be solved by the present invention is to solve these problems of the prior art, to reliably and smoothly discharge slime, and to greatly improve drilling speed and drilling efficiency. It is to provide a rod.

[0004]

Means for solving the above problems are as follows: 1) An inner cylinder is inserted into an outer cylinder and a space for discharging slime is provided between the outer cylinder and the inner cylinder. With the formed double pipe structure, a bit is connected to the lower end of the inner pipe, and the outer peripheral surface of the bit is elongated and recessed in the vertical direction from the lower end to the upper end to form a space between the outer cylinder and the inner cylinder. In a boring rod having a communicating slime discharge path, a ring-shaped recess is formed in the middle of the discharge path, and the slime is discharged smoothly by providing the pool in the middle of the discharge path. 2) The boring rod described above, wherein a plurality of discharge paths are provided, and the outer peripheral surface of the bit is recessed in a ring shape so that the reservoir communicates with each discharge path to form a reservoir. On the bowling rod.

[0005]

The boring rod according to the present invention is installed in a drilling rig, is given a rotation and a hitting force by a rotary hitting device of the drilling rig, and is propelled toward the ground to excavate. The bit of the boring rod is rotated by the rotation of the excavator, and the excavated slime is discharged to the space between the outer cylinder and the inner cylinder via the discharge path, and is discharged directly to the ground. The slime is discharged to the pool provided in the middle of the discharge path, and is discharged again to the space between the outer cylinder and the inner cylinder through the remaining discharge path. Even when slime containing excavated stones and debris enters the discharge channel and the speed at which the slime is discharged is reduced, the excavated stones and debris that cause the speed of the slime to be reduced are stored in the reservoir, and are collected on the discharge channel. The discharge path can be secured and the discharge speed can be prevented from lowering. For this reason, slime does not accumulate on the bit blade tip surface, and excavation can be performed smoothly and efficiently. In the boring rod according to the second aspect of the present invention, since a plurality of discharge paths are provided and the reservoir is provided so as to be connected to all the discharge paths, even if any one of the discharge paths is clogged, the slime is reduced. Excavation efficiency is good because it can be discharged into the space between the outer cylinder and the inner cylinder through another discharge path.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The number of discharge paths formed by recessing the outer peripheral surface of a bit from the lower end to the upper end of the bit is desirably plural, but may be one. The discharge path is desirably provided spirally on the outer peripheral surface of the bit. When there are a plurality of discharge paths, it is desirable that the outer peripheral surface of the bit be recessed in a ring shape to provide a pool so as to communicate with all the discharge paths. The outer cylinder may or may not rotate. The outer cylinder has a configuration in which a plurality of cylinders are connected in the longitudinal direction, and a case in which a single cylinder is used.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 is an explanatory view showing a use state of the present embodiment, FIG. 2 is an explanatory view showing a state in which the boring rod of the present embodiment is mounted on an excavator, and FIG. 3 is a longitudinal sectional view of the boring rod of the present embodiment. 4 is a bottom view showing the bit tip surface of this embodiment, FIG. 5 is a partially cutaway front view showing a terminal joint of this embodiment, FIG. 6 is a sectional view taken along line AA in FIG. 1, and FIG. B at 1
It is B sectional drawing.

In this embodiment (see FIGS. 1 to 7), reference numeral 1 denotes a boring rod, 2 denotes an inner tube formed by screwing a plurality of predetermined lengths, and 3 denotes a predetermined length. A plurality of outer tubes 4 are screwed into a long length, 4 is an inner bit attached to the lower end of the inner tube 2, 5 is a female screw provided on the lower inner surface of the outer tube 3, and 6 is screwed to a lower end of the outer tube 3. A ring bit, 7 is a male screw portion provided on the upper portion of the ring bit 6, 8 is a step provided on the lower inner side of the ring bit 6, 9 is a hitting surface provided on a lower portion of the inner bit 4 for hitting the step, Reference numeral 10 denotes a step provided on the inner wall of the pipe below the outer pipe 3, reference numeral 11 denotes a middle press-fitting part which contacts the same step and acts to pull the outer pipe 3 downward.
2 is an insertion hole 1 whose upper part is provided at the center inside the adapter 12a.
3 and the lower part is screwed to the head of the inner tube 2 to make the adapter 1
An extension rod for transmitting the rotation and impact force of 2a to the inner tube 2, 12a is an adapter, 13 is an insertion hole, 14 is a terminal joint screwed to a lower end of the adapter 12a, and 15 is a screw connection of an upper end of the outer tube 3. Outer pipe fitting screwed at part 16, 16
Is a threaded portion provided at the upper end of the outer tube 3, and 17 is a terminal joint 14.
, A threaded portion between the inner tube 2 and the extension rod 12, a threaded portion 19 between the inner tube 2 and the middle push-in joint portion 11, and a middle push-in joint 20 At the lower end of the widened portion of the portion 11, the outer tube pulling surface which comes into contact with the step portion 10 of the outer tube 3, 21 is the threaded portion between the inner bit 4 and the middle push joint portion 11, and 22 is the complete connection between the female screw 5 and the male screw 7. A screw gap at the time of screwing in, 23 is a connection portion by screwing the outer tubes 3 together, 24 is a rotary hitting device, 25 is a guide provided with a rotary hitting device and a boring rod 1 which are tiltably mounted on a crawler wheel or the like. A cell, 26 is a lower guide of the boring rod 1, 27 is a slide base of the guide cell 25, 27 a is a connecting member, 28 is a plurality of discharge paths formed by recessing the outer peripheral surface from the lower end to the upper end of the inner bit 4. , 29 A pool formed by recessing the outer peripheral surface at the center of the inner bit 4 into a ring shape and communicating with the respective discharge passages 28, 30 is a slime, 30a is a digging piece included in the slime 30, and 31 is a bit tip surface. , 32 is the outer tube 3
And the inner tube 2.

The boring rod 1 according to the present embodiment comprises an outer tube 3
And the inner pipe 2 are held between the lower guide 26 on the guide cell 25 of the excavator and the rotary hitting device 24.
linked by a. The rotary hitting device 24 is provided on a slide table 27 and can move along the guide cell 25. When the boring rod 1 is driven into the ground, the next outer pipe 3 and the inner pipe 2 are screwed together and connected in multiple stages, and are driven deep into the ground. The bit hitting surface 31 of the boring rod 1 is rotated and excavated by the operation of the rotary impact device 24. In addition, since high-pressure water or air is injected into the excavation hole, pressure is applied to the slime 30 excavated by the rotation of the bit tip surface 31, and the slime 30 is formed on the outer peripheral surface of the inner bit 4. A space 32 between the outer pipe 3 and the inner pipe 2 through the discharge path 28
It is discharged to. In the middle of the discharge path 28, each discharge path 2
8 is formed, the reservoir 29 communicating with the discharge passage 2 is formed.
Even if slime 30 concentrates in 8 and enters, slime 30
Slime 3 by temporarily discharging
Thus, the flow in the discharge path 28 can be smoothly performed. The slime 30 discharged into the reservoir 29 is smoothly discharged to the space 32 between the outer pipe 3 and the inner pipe 2 via any one of the discharge paths 28. Further, by providing the pool portion 29 in the middle of the discharge path 28, the discharge path 28
Even when the slime 30 including the excavated pieces 30a of a size that is difficult to pass through the inside enters the discharge path 28 and the flow in the discharge path 28 is deteriorated, the slime causing the flow of the discharge path 28 to be deteriorated. By accommodating the large excavated pieces 30a included in the 30 in the accumulation portion 29, the slime 30 can be smoothly discharged, the slime 30 is prevented from accumulating on the bit tip surface 31, and excavation can be performed efficiently. I can do it.

When the rotary hitting device 24 operates and a hitting force is applied to the adapter 12a, the insertion hole 1 of the adapter 12a is inserted.
The ceiling wall 3 hits the head of the extension rod 12, and the hitting force is transmitted to the inner pipe 2 and the inner bit 4 attached to the lower end thereof. The striking force transmitted to the inner tube 2 is applied to the step 8 of the ring bit 6 via the striking surface 9 at the lower portion thereof, and the ring bit 6 is also struck at the same time as the inner bit 4. Even if the impact force of the adapter 12a is transmitted through the terminal joint 14, there are gaps between the outer pipe joint 15 and the terminal joint 14, and between the lower end of the outer pipe 3 and the ring bit 6, and the outer pipe 3 Since the outer tube 3 is vertically movable, no impact force is applied to the outer tube 3.

Next, the rotational force of the adapter 12a is transmitted to the extension rod 12 by fitting the insertion hole 13 and the head of the extension rod 12, and furthermore, the inner force is transmitted through the inner pipe 2 and the middle push joint portion 11. The bit 4 is transmitted, and the inner bit 4 rotates. The inner bit 4 is rotated by the inner bit 4 and the ring bit 6 because the inner bit 4 is inserted so as to engage with the ring bit 6 when the inner bit 4 rotates. Excavate. Also, pushing the outer tube 3
When the rotary hitting device 24 is moved downward, the adapter 12
a pushing force acts on the extension rod 1
2. The inner bit 4 is pressed through the inner pipe 2 and the middle pressing joint portion 11. Also, the terminal fitting 1 is connected to the adapter 12a.
4. The outer tube 3 is pushed through the outer tube pushing surface 17 and the outer tube joint 15. Also, a part of the outer tube pulling surface 20 of the middle push joint portion 11 connected to the lower end of the inner tube 2 presses the lower step portion 10 of the outer tube 3 and presses the outer tube 3 in the ground direction so as to be pulled at the lower portion. .

Here, the male thread portion 7 of the ring bit 6
Since the female screw 5 of the outer tube 3 is completely screwed beyond the length of the screw, the outer tube 3 is not rotated even if the ring bit 6 rotates. The ring bit 6 can rotate freely regardless of the outer tube 3. Further, since the screw of the female screw 5 and the male screw 7 is threaded in a direction opposite to the drilling rotation, the ring bit 6 does not come off the outer tube 3 during drilling.

[0013]

According to the present invention, the slime can be discharged reliably and smoothly, so that the speed of discharging the slime is improved, the slime is less likely to accumulate on the bit tip surface, and the excavation efficiency is greatly improved. In the invention according to claim 2, there are a plurality of discharge paths, and the reservoir is formed so as to be in communication with each of the discharge paths, and any one of the discharge paths is clogged or the flow becomes poor. In this case, since the slime can be discharged through another discharge path, the slime can be discharged quickly and reliably, and the excavation efficiency can be greatly improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a use state of the present embodiment.

FIG. 2 is an explanatory view showing a state in which the boring rod of the present embodiment is mounted on an excavator.

FIG. 3 is a longitudinal sectional view of the boring rod of the present embodiment.

FIG. 4 is a bottom view showing the bit tip surface of the embodiment.

FIG. 5 is a partially cutaway front view showing a terminal joint in the embodiment.

FIG. 6 is a sectional view taken along the line AA in FIG.

FIG. 7 is a sectional view taken along the line BB in FIG. 1;

[Description of Signs] 1 Boring rod 2 Inner tube 3 Outer tube 4 Inner bit 5 Female screw 6 Ring bit 7 Male screw 8 Step 9 Hitting surface 10 Step 11 Medium push joint 12 Extension rod 12a Adapter 13 Insertion hole 14 Terminal joint 15 Outer pipe joint 16 Threaded part 17 Outer pipe pushing surface 18 Threaded part 19 Threaded part 20 Outer pipe pulling surface 21 Threaded part 22 Thread gap 23 Connection part 24 Rotary hitting device 25 Guide cell 26 Lower guide 27 Slide base 27a Connection Member 28 Discharge path 29 Reservoir 30 Slime 30a Drilled piece 31 Bit edge 32 Space

Continuation of the front page (56) References JP-A-4-353189 (JP, A) JP-A-8-42276 (JP, A) JP-A 7-34089 (JP, U) JP-A 7-42859 (JP, A) , U) Japanese Utility Model Application Hei 4-92092 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21B 17/00 E21B 4/06 E21C 1/12 E21D 9/04

Claims (2)

(57) [Claims] 1. A double pipe structure in which an inner cylinder is inserted into an outer cylinder and a space for discharging slime is formed between the outer cylinder and the inner cylinder, and a bit is connected to a lower end of the inner pipe. A boring rod having a longitudinally recessed outer peripheral surface of the bit extending from a lower end to an upper end to form a slime discharge passage communicating with a space between the outer cylinder and the inner cylinder; Form a ring-shaped recessed part in the middle,
A boring rod, characterized in that the slime can be smoothly discharged by providing the pool portion in the middle of the discharge path. 2. The boring rod according to claim 1, wherein a plurality of discharge paths are provided, and the pool is formed by recessing the outer peripheral surface of the bit into a ring shape so that the pool communicates with each discharge path.