JP3422940B2 - Sheath tube structure of material for ground drilling - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheath pipe of a material for ground drilling, which is used when drilling a ground for draining water, injecting a chemical, or the like. Regarding the structure. 2. Description of the Related Art Conventionally, a rod having a hollow hole has been inserted into a sheath tube as disclosed in Japanese Utility Model Publication No. Hei 7-43264, for example, as a material for ground drilling. A plurality of pipes are connected to each other and used in a long length, a drill bit is attached to the tip of the most advanced rod and the sheath pipe, and a striking force is applied while rotating both bits,
Further, there is known an apparatus in which drilling is performed by jetting water through a hollow hole of a rod. The water used for drilling is drained together with the slime through the space between the sheath tube and the rod. In addition, there is also known a method in which a drill bit is attached to only the tip of a most advanced rod to perform drilling. [0003] However, when drilling using the above materials, a large frictional force acts between the outer peripheral surface of the sheath tube and the wall surface of the drilling hole. It takes a long time, a large power source is required, and the entire device becomes large. This is particularly noticeable when the length of the hole is increased. On the other hand, in order to solve such a problem,
When a drill bit is attached only to the tip of the most advanced rod, the drill bit is a mechanism that can project radially outward from the outer peripheral surface of the sheath tube, and drilling is performed in the projected state Make the diameter of the drill hole larger than the outer diameter of the sheath tube,
Various proposals have been made and practically used in which a gap is formed between the outer peripheral surface of the sheath tube and the wall surface of the hole so that no frictional force acts. However, in this type, the mechanism for projecting the bit outward in the radial direction is structurally complicated including many parts, and the strength of each part is sufficiently secured because it is necessary to minimize each part. Cannot be performed, and there is a defect such as lack of durability. [0005] The present invention has been made in view of the above-mentioned points, and an object thereof is to reduce the frictional force acting between the hole and the wall surface of the hole during drilling as much as possible.
An object of the present invention is to provide a sheath pipe structure of a material for ground drilling capable of sufficiently securing the strength of a state-of-the-art rod and members and components attached thereto. [0006] In order to solve the above-mentioned problems, according to the first aspect of the present invention, a rod having a hollow hole is inserted into a sheath tube, and a plurality of the rods and the sheath tube are provided. Attach a drilling bit at least to the tip of the most advanced rod, apply a striking force while rotating this bit, and further eject water through the hollow hole of the rod As the sheath pipe structure of the drilling material for drilling the ground, the leading end pipe, which is the most advanced sheath pipe, is formed in an enlarged diameter shape at the tip end, the outer diameter of which is larger than that of the rear end. The outer diameter of the other sheath tube is set to be smaller than the outer diameter of the front end of the front conduit and substantially equal to the outer diameter of the rear end. In this configuration, during drilling, only the distal end of the large-diameter end pipe of the plurality of sheath tubes comes into contact with the wall surface of the bore hole, and the outer peripheral surface of the sheath tube and the wall surface of the bore hole are formed. The frictional force acting between them becomes very small. In addition, since the leading pipe is formed in a tip-diameter enlarged shape, the most advanced rod inserted into the leading end side of the leading pipe and a member attached thereto, for example, a drilling bit or the bit is radially outward. The parts of the mechanism to be protruded can be made larger by the larger outer diameter of the leading conduit, and the strength can be increased. Further , the invention according to claim 1 has the above-mentioned configuration.
In addition, a drill bit for the sheath tube side different from the drill bit for the rod side is rotatably attached to the leading conduit,
The drill bit is configured so that a turning force and a striking force are applied from a stem, which is the most advanced rod. In this configuration, drilling is performed by both the drilling bit on the rod side and the drilling bit on the sheath tube side, and the friction acting between the outer peripheral surface of the sheath tube and the drilling wall surface described above. The drilling efficiency is further enhanced in combination with the reduced force. Further, the invention according to claim 1 is as described above.
In addition to the above configuration, one end of a cylindrical mounting piece is fitted into the distal end opening of the front conduit, and the outer peripheral end of the mounting piece is drilled through the lock ring through a lock ring. Is rotatably mounted. In this configuration, since the drilling bit on the sheath tube side and the distal end side, which is the enlarged diameter side of the leading pipe, smoothly continue through the mounting piece, the drilling function by rotation of the drilling bit and the leading pipe are provided. The function of expanding the hole diameter by the tip side of the hole is smoothly exhibited, and the drilling efficiency is further enhanced. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an exploded state of a soil drilling material according to an embodiment of the present invention. The soil drilling material is obtained by draining the sheath tube 1 shown in FIG. )
1C and an inner rod 3 shown in FIG. 1C. When drilling a ground, the inner rod 3 is inserted into the sheath tube 1 or 2 and used. . The drainage sheath tube 1 is a state-of-the-art front conduit 1.
, And a plurality of relay pipes 12, 12,..., And a rear end terminal pipe 13 are sequentially connected in accordance with the progress of drilling. The front conduit 11 is made of a metal such as steel, and a cylindrical mounting piece 16 is fitted and fixed by press-fitting into a distal end portion thereof. A lock ring is provided on an outer periphery of a portion of the mounting piece 16 protruding outside the front conduit 11. A diameter-enlarging bit 18 as a drilling bit on the sheath tube side is rotatably mounted via 17. Each of the relay pipe 12 and the terminal pipe 13 is made of a synthetic resin such as polyethylene resin. A steel pipe joint 19a or 19b having a threaded portion (male screw or female screw) at both ends of the relay pipe 12 and one end of the terminal pipe 13, respectively. Are connected, and the relay pipes 12 and 19 are connected through the pipe joints 19a and 19b.
12 or relay pipe 12 and leading pipe 11 or terminal pipe 1
3 is connected. The length of the relay tube 12 and the terminal tube 13 is about 3 m.
Are connected and used within a maximum length of about 30 m. Further, the front conduit 11 is a distal end side 1 which is a fitting side of the mounting piece 16 (and thus a mounting side of the enlarged diameter bit 18).
The outer diameter of the end pipe 1a is larger than that of the rear end 11b, and the outer diameter of the relay pipe 12 and the end pipe 13 is smaller than the outer diameter of the front end 11a of the front pipe 11. It is set substantially equal to the outer diameter of the end side 11b. Although not shown, the rear end side 11b of the front pipe 11 and the relay pipe 1 are not shown.
A plurality of small holes for drainage are provided at predetermined intervals in the length direction of each of the terminal tube 2 and the terminal tube 13. The sheath tube 2 for injecting the chemical is also the same as the sheath tube 1 for draining water, and the leading end pipe 21 and a plurality of relay pipes 22,
, And the rearmost terminal tube 23 are sequentially connected in accordance with the progress of drilling. The front conduit 21 is made of metal such as steel, and has a cylindrical mounting piece 2 inside its distal end.
6 is fitted and fixed, and an enlarged diameter bit 28 as a drill bit for the sheath tube is rotatably mounted on the outer periphery of a portion of the mounting piece 26 protruding outside the front conduit 21 via a lock ring 27. Have been. The relay pipe 22 is made of a metal such as steel, while the terminal pipe 23 is made of a synthetic resin such as polyethylene resin. The relay pipes 22 and 22 or the relay pipe 22 and the front pipe 21 are connected by a screwing structure, respectively. 23 and the relay pipe 22 are connected via a pipe joint 29. The front conduit 21 is formed to have a tip-end enlarged shape in which the outer diameter of the distal end 21a, which is the fitting side of the mounting piece 26, is larger than that of the rear end 21b, like the front conduit 11 of the drainage sheath tube 1. , The outer diameter of the relay pipe 22 and the outer diameter of the terminal pipe 23 are smaller than the outer diameter of the front end 21 a of the front pipe 21 and the rear end 2.
It is set to be substantially the same as the outer diameter of 1b. In addition, the first conduit 2
The length 1 is set to be longer than that of the leading conduit 11 of the drainage sheath tube 1, and the rear end side 21 b of the leading conduit 21 and the relay tube 22, although not shown, each have a plurality of lengths. Small diameter chemical injection holes are provided at predetermined intervals in the length direction. On the other hand, the inner rod 3 comprises a stem 31 which is the most advanced rod, an adjusting rod 32 connected to the rear end of the stem 31, and a plurality of connecting rods 33,3.
Each of these rods 31 to 33 is made of metal such as steel and has a hollow hole 35 on the center line. In addition, two rods 31 to 33 are connected to each other.
Type and the sleeve 36 and 37 are used, one of the sleeve 36 simply while only connecting rod to each other, the other of the sleeve 37, in addition to connecting between the rod sheath pipe 1 or the rod 2 (the relay pipe 12 or 22) has a guide function of concentrically holding it. As shown in FIG. 2, the stem 31 is attached to the mounting piece 16 from within the front conduit 11 or 21 of the sheath tube 1 or 2.
Or 26 and a diameter-enlarging bit 18 or 28, and extends to the outside. A pilot bit 38 as a rod-side drilling bit is rotatably mounted on a tip portion which is an extended portion thereof. I have. The structure of this part is enlarged and shown in FIGS. That is, the stem 31 is formed symmetrically with respect to the plane including the axial center line L (the plane perpendicular to the drawing in FIG. 2), and can be used upside down. In addition, the outer diameter gradually decreases in three steps from the vicinity of the center line L to both ends (in FIG. 1, the outer diameter changes only in two steps for simplicity). Large diameter portion 31a, first middle diameter portion 3
1b, a second middle diameter portion 31c and a small diameter portion 31d. The large-diameter portion 31a near the center line L of the stem 31 and the first middle-diameter portion 31b connected to the large-diameter portion 31a are attached to the mounting piece 16 or 26.
It is fitted inside so as to be relatively rotatable. A striking surface 31e, which is a step between the large diameter portion 31a and the first middle diameter portion 31b, is formed in a tapered shape, and is formed on the inner peripheral surface of the mounting piece 16 or 26 corresponding to the striking surface 31e. A striking force is applied to the enlarged bit 18 or 28 via the mounting piece 16 or 26 in contact with the tapered surface 16a or 26a. An annular groove 41 is formed on the outer peripheral surface of the mounting piece 16 or 26 at a position protruding from the inside of the front conduit 11 or 21. A pair of lock rings 17 or 27 inserted into the annular groove 41 are provided. A diameter-enlarging bit 18 or 28 is rotatably mounted via the pin. This expanding bit 18 or 2
8 has a through hole 42 through which the second middle diameter portion 31c of the stem 31 penetrates on the tip side from the fitting portion to the mounting piece 16 or 26, and three through holes around the through hole 42. The notches 43, 43, 43 are formed at substantially equal intervals in the circumferential direction. On the other hand, the second middle diameter portion 31c of the stem 31 has three protruding portions 44, 44, 4 made of a high-speed material protruding in the radial direction corresponding to the respective notches 43.
4 are provided, each of these protrusions 44 penetrates the corresponding notch 43 and engages in the rotational direction to transmit the rotational force from the stem 31 to the enlarged diameter bit 18 or 28, The enlarged bit 18 or 28 rotates about the mounting piece 16 or 26. Each of the notches 43 has a width in the circumferential direction set to be at least twice as large as the thickness of the projection 44.
When the stem 31 is inserted into the through hole 42 of the diameter-enlarged bit 18 or 28, each projection 44 is easily fitted into the notch 43. The notch 43 and the protrusion 44
In the circumferential direction constitutes a part of the drainage channel, and this gap is formed on the outer peripheral surface of the stem 31 so as to straddle the two axially front and rear second middle diameter portions 31c, 31c. The water used for drilling is communicated with the drainage grooves 45 and the sheath tube 1 is passed through these.
Alternatively, the water is guided into the space between the inner rod 2 and the inner rod 3 and drained. Further, the outer peripheral surface of the small diameter portion 31d of the stem 31 protruding forward from the through hole 42 of the diameter-enlarging bit 18 or 28 has the same counterclockwise rotation and large pitch as the rotation direction of the stem 31 during drilling. A male screw 47 is formed, and a female screw 4 formed on the pilot bit 38 is formed on the male screw 47.
By screwing 8, the pilot bit 38 is mounted on the small diameter portion 31 d which is the end of the stem 31. The pilot bit 38 is formed in such a size that it can be pulled out through the through hole 42 and the notch 43 of the enlarged diameter bit 18 or 28. When the male screw 47 is used with the stem 31 turned upside down, as shown in FIG.
Or, it is adapted to be screwed into the female screw 37a of the sleeve 37 connected to the adjustment rod 32 in the inside 21. Next, the operation and effect of the above embodiment will be described by taking as an example a case where drilling for draining water is performed in front of the excavating face 50 of the tunnel shown in FIG. FIG.
Reference numeral 51 denotes a guide cell of a drilling machine (for example, a hydraulic drill jumbo or the like), 52 denotes a tip guide attached to the tip of the guide cell 51, and 53 denotes a guide cell 51 on the guide cell 51 via a slide table. Is a rotary hitting device provided so as to be movable along. When drilling water, first, a pilot bit 38 is attached to one end of the stem 31 of the inner rod 3.
After connecting the adjustment rod 32 to the other end, the stem 31 is inserted together with the adjustment rod 32 into the front conduit 11 of the drainage sheath tube 1, and the distal end of the stem 31 and the pilot bit 38 are connected to the front conduit. 11 is made to penetrate through the through hole 42 of the enlarged diameter bit 18 previously attached to the distal end side of the bit 11 and protrude outside. Subsequently, a relay pipe 12 is connected to the above-mentioned front pipe 11,
The connecting rods 33 are connected to the adjusting rods 32, respectively, to form a ground drilling material having a predetermined length, and the material is mounted between the tip guide 52 of the guide cell 51 and the rotary hitting device 53. Thereafter, the rotary hitting device 53 is operated, and both the rotating force and the hitting force are transmitted from the rotary hitting device 53 to the pilot bit 38 and the diameter expansion bit 18 on the material front end via the inner rod 3. 18,
In addition to the rotation of the shaft 38 and the application of the striking force from the bits 18, 38, water is blown out through the hollow hole 35 of the inner rod 3 so that a hole 56 is formed in front of the excavation face 50.
I do. Then, the drilling hole 56 is formed to a desired length while sequentially connecting the relay pipe 12 or the terminal pipe 13 to the connecting rod 33 according to the progress of the drilling hole 56. still,
The water used for the drilling 56, together with the slime, enters into the space between the sheath tube 1 and the inner rod 3 through the gap between each projection 44 of the stem 31 and the notch 43 of the enlarged diameter bit 18. It flows in and is drained to the tunnel side through it. At the time of this drilling, the leading end pipe 11, which is the most advanced sheath pipe, is connected to the distal end 1 on the side where the diameter-enlarging bit is attached.
The outer diameter of 1a is formed to be larger at the tip end than that of the rear end side 11b, and the outer diameters of the relay tube 12 and the terminal tube 13 are smaller than the outer diameters of the front end side 11a of the leading conduit 11. Since the outer diameter of the rear end side 11b is set to be substantially the same as that of the rear end side 11b, of the sheath tube 1 whose overall length corresponds to the length of the drilled hole 56, the leading conduit 1
Only the tip side 11a of the hole 1 contacts the wall surface of the hole 56, and the frictional force acting between the outer peripheral surface of the sheath tube 1 and the wall surface of the hole 56 becomes very small. For this reason, the drilling efficiency can be increased and the drilling time can be shortened, and the output of the rotary impact device 53 required for drilling can be reduced, which can contribute to downsizing and the like. Further, since the front conduit 11 is formed to have an enlarged diameter at the front end, the diameter of the stem 31 inserted into the front end side 11a of the front conduit 11 can be increased accordingly, and the durability thereof is improved. be able to. In addition, drilling is performed by both the rod bit 38, which is a drilling bit on the rod side, and the diameter-enlarging bit 18, which is a drilling bit on the sheath tube side. The force is transmitted through the inner rod 3 and the energy loss is reduced as compared with the case where the rotational force is transmitted through the sheath tube 1, so that the drilling efficiency is improved and the rotary hitting device 53 and the like are downsized. Can be further improved. Further, in the above-described embodiment, when the enlarged diameter bit 18 is rotatably mounted on the distal end 11a of the front conduit 11, one end of the cylindrical mounting piece 16 is fitted into the opening on the distal end 11a of the front conduit 11. The enlarged diameter bit 18 is rotatably attached to the outer periphery of the other end of the mounting piece 16 via the lock ring 17 so that the enlarged diameter bit 18 and the distal end side 11a of the front conduit 11 are attached. Peace 1
6, the drilling function by the rotation of the diameter expanding bit 18 and the hole expanding function by the distal end 11a of the front conduit 11 can be smoothly exhibited, and the drilling efficiency is improved. Can be further improved. In the above embodiment, the pilot bit 38 is attached to the distal end of the stem 31 which is the most advanced rod, and the enlarged diameter bit 18 or 28 is attached to the distal end of the leading conduit 11 or 21 which is the most advanced sheath tube. In the description above, a drilling force is applied by applying a striking force while rotating both of the bits and by jetting water through the hollow hole 35 of the rod. The present invention can be similarly applied to a drill that applies a striking force while rotating this bit and further drills water by ejecting water through the hollow hole of the rod. As described above, according to the sheath pipe structure of the drilling material of the present invention, the frictional force acting between the outer peripheral surface of the sheath pipe and the wall face of the drill hole is maximized. Therefore, drilling efficiency can be increased and drilling time can be shortened. In addition, since the front pipe is formed to have an enlarged diameter at the front end, the state-of-the-art rod inserted into the front end side of the front pipe and members and components attached thereto can be enlarged accordingly, and their strength can be increased. It can be increased to contribute to improvement of durability and the like. In addition, the drilling efficiency can be further increased in combination with drilling by both the drilling bit on the rod side and the drilling bit on the sheath tube side, and the drilling time can be shortened. Can be further improved. Further, the drilling bit on the sheath tube side and the distal end side, which is the enlarged side of the front pipe, are smoothly continuous via the mounting piece, and the drilling function by rotation of the drilling bit and the like are performed. The function of expanding the hole diameter by the distal end side of the conduit can be smoothly exhibited, and the drilling efficiency can be improved, and the drilling time can be further reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view of a material for ground drilling according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing a structure of a tip portion of the material. FIG. 3 is a longitudinal sectional view showing a fitting structure of a stem, which is a constituent member of the material, to a mounting piece and an enlarged bit; FIG. 4 is a front view of the fitting structure as viewed from a distal end side of a stem. FIG. 5 is a work state diagram for explaining the operation and effect of the embodiment. [Description of Signs] 1 sheath tube for draining water 2 sheath tube for chemical injection 3 inner rod 11, 21 forward conduit 12, 22 relay tube 13, 23 terminal tube 16, 26 mounting piece 17, 27 lock ring 18, 28 diameter expansion Bit (Drill bit for sheath tube side) 31 Stem 38 Pilot bit (Drill bit for rod side)

Continued on the front page (72) Koji Sasaki 25-32 Tamatecho, Kashiwara-shi, Osaka Sasaki Giken Co., Ltd. (72) Takao Maeda 2 Dejima Nishimachi Sakai-shi, Osaka 56) References JP-A-4-315605 (JP, A) JP-A-7-42858 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E21B 17/00-17/08

Claims (1)

(57) [Claim 1] A rod having a hollow hole is inserted into a sheath tube, and a plurality of the rods and the sheath tubes are connected to each other to form a long tube. A drilling bit is attached to the tip of the rod, a striking force is applied while rotating the bit, and water is jetted through the hollow hole of the rod to drill the ground. The front end of the front end sheath tube has an outer diameter at the front end side that is larger than that at the rear end side, and is formed in an enlarged end shape. Is set to be substantially the same as the outer diameter of the rear end side smaller than the outer diameter of the front end side, and the front pipe has a different hole from the rod drilling bit on the rod side.
The drill bit on the sheath tube side is attached rotatably,
Rotational force from cutting-edge rod stem to drill bit
And a striking force. One end of a cylindrical mounting piece is provided in the opening at the distal end of the front conduit.
The ends are fitted, and the outer periphery of the other end of the mounting piece is
The drill bit on the sheath tube side can be freely rotated via the cling.
A sheath tube structure of a material for ground drilling, characterized in that it is mounted on a ground.