JPH08144675A - Excavating device - Google Patents

Abstract

PURPOSE: To provide an excavating device having improved durability by enhancing strength of an expansion bit and executing excavation efficiently by effecting rotation of low torque. CONSTITUTION: A slidable cylindrical body 20 is provided between a device 7 with a discharge groove 14 and a stopper collar 2. A stopper ring 21 is provided at the proximal end of the body 20. A hole 13 for filling slime is provided in the body 20 so as to communicate with the groove 14. A part of slime S passing through the device 7, collar 2, and the groove 14 is filled into the hole 13 so that the device 7 and the coller 2 can be connected in the form of a pin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digging apparatus used for digging a buried pipe in the ground for water well, anchor work, landslide prevention, etc., and more particularly to a digging apparatus provided with a hole expanding bit.

[0002]

2. Description of the Related Art Conventionally, in excavation in which a casing pipe made of a steel pipe or the like of this kind is buried in the soil, a device is connected to a tip of a drill hammer, a bit head is provided at the tip of the device, and the bit protrudes from the tip of the casing pipe. Drilling is performed by applying an impact force and a rotational force to the bit head, and the drill hammer transmits the rotational force to the device via, for example, a spline groove. In order to easily insert the casing pipe into the ground, a bit device that can be expanded to a diameter larger than that of the casing pipe is used. As the bit device, a bit device having substantially the same diameter as that of the device is provided on the bottom surface of the device. A bit device for forming a semicircular two-divided block and projecting these blocks from the outer peripheral surface of the device by a predetermined amount of excavation to increase the drilling diameter is proposed in Japanese Examined Patent Publication No. 3-21717 and divided into three. It is known that the block is projected from the outer peripheral surface of the device by a predetermined amount of excavation to increase the drilling diameter, and that the bit head is eccentric by an eccentric shaft to increase the drilling diameter.

[0003]

In each of the above-mentioned conventional bit devices, since the blocks divided into a plurality of pieces are projected and moved, or the bit head is eccentric by the eccentric shaft to expand the drilling diameter, the structure is complicated. Then, there is a problem that it becomes fragile and that the recovery work performed by reducing the bit device after the excavation becomes complicated. In addition, even if the drilling diameter increases due to the above movement and eccentricity, the bit head itself does not increase, the tip area of the bit head becomes smaller than the excavation area, and the side of the bit head bites into the excavation surface during rotation. The rotation resistance becomes large, and the bit head is likely to be partially worn, and a large rotating torque is required, so that the bit head is not only easily worn partially, but also a spline groove for transmitting rotation to the bit head. And the like become worn out in a short time and become unusable.

Accordingly, an object of the present invention is to provide a drilling device which improves the strength of a drill bit, enables efficient drilling with low torque rotation, and has excellent durability.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a bit head is provided at the tip of a device which receives an impact force and a rotational force and is provided with a discharge groove on the outer periphery thereof, and an outer step portion is formed on the outer periphery of the device, and a casing. The striking collar provided at the tip of the pipe is provided with an inner step portion, the impact force is transmitted to the striking collar through these step portions, and the impact force of the bit head protruding from the tip end of the striking collar and In an excavating device for excavating by a rotational force, a tubular body is provided between the device and a hitting collar, and a hitting ring arranged between the both step portions is provided at a base end of the tubular member, and the tubular body is provided. Of the hitting collar is provided with an enlarged hole bit having a diameter larger than that of the hitting collar, and a slime-filling concave portion that is capable of communicating with the discharge groove is provided in the cylindrical body. Excavation equipment It is.

[0006]

With the above structure, the outer step portion of the device strikes the hitting ring to transmit the impact force to the hole-expanding bit, and the hole-expanding bit and the bit head strike the entire excavation surface to perform excavation. Be seen. Further, by filling a part of the slime passing through the discharge groove into the concave portion, it is possible to integrally connect the cylindrical body and the device and transmit the rotational force of the device to the hole expanding bit.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. 1 to 6, a striking collar 2 made of steel or the like is welded to the tip of a casing pipe 1 made of a steel pipe or the like, and the striking collar 2 is attached to a thin portion 3 on the base end side of the casing pipe 1. The tip is inserted and welded. Although the small hole 1A is provided in the casing pipe 1, it may not be provided. Reference numeral 4 denotes a thick portion on the tip side of the hitting collar 2. A drill hammer 5 is inserted into the casing pipe 1, a drill rod 6 for rotating the drill hammer 5 is connected to an upper portion of the drill hammer 5 in the drawing, and a device 7 made of steel or the like is connected to a lower portion thereof. The drill hammer 5 includes an air hammer (not shown) that transmits an impact force to the device 7 by the compressed air sent from the drill rod 5. A spline groove 9 is integrally formed on the outer periphery of the connecting cylinder portion 8 located at the base end of the device 7, and the spline groove 9 is fitted into the vertical groove 10 of the drill hammer 5 to allow the drill hammer 5 to move. The rotational force is transmitted to the device 7, and the air hammer strikes the connecting tube portion 8 to transmit the impact force to the device 7. The device 7
A bit head 11 is provided at the tip of the bit head 11. A plurality of bits 12 made of cemented carbide are provided on the bit head 11, and a plurality of vertical grooves 13 are provided on the outer periphery of the bit head 11.
And the discharge grooves 14 are formed at three equal intervals on the outer periphery of the device 7. Further, an exhaust passage 15 is formed inside the device 7, and the exhaust passage 15 communicates with an exhaust port 16 at the tip of the bit head 11,
The compressed air supplied from the drill rod 6 blows out from the exhaust port 16 through the exhaust passage 15, and the blown compressed air causes the vertical groove 13 and the discharge groove 14 together with the crushed stones, small gravel (slime), etc. It passes through and is discharged above the casing pipe 1. Further, an outer peripheral step portion 17 which is an outer step portion is formed on the outer periphery of the device 7 on the base end side. Reference numeral 18 denotes an inner peripheral step portion which is an inner step portion formed at the base end of the hitting collar 2.

Reference numeral 20 is a cylindrical body provided slidably in the circumferential direction of 360 degrees. Further, a hitting ring 21 which is a receiving portion is integrally provided at the base end of the cylindrical body 20, and the hitting ring 21 has an upper surface shown in the figure engageable with the outer peripheral step portion 17 and a lower surface shown in the figure. It is provided so as to be engageable with the inner peripheral step portion 18. Further, the tip of the tubular body 20 projects from the tip of the striking collar 2, and the expanding hole bit 22 having a substantially cylindrical shape and having a diameter larger than that of the striking collar 2 is integrally provided on the projecting tip. A plurality of bits 12A are provided on the tip surface of the expanded hole bit 22.
Is provided. The device 7 is removably fitted in the tubular body 20, and the outer surface 7A of the device 7 is slidably fitted in the inner surface 20A of the tubular body 20 so that the device 7 can be rotated. It is configured so that it can be transmitted to. That is,
In the tubular portion 20B of the tubular body 20 between the hitting ring 21 and the expanded hole bit 22, there is formed one hole 23, which is a recess for slime filling, which communicates with the discharge groove 14 and communicates with the inside and outside. A thin plate 24 made of steel or a spring material is provided outside the cylindrical portion 20B.
Is externally fitted, and further, on the outside of the hitting ring 21, a thin plate 25 made of steel and a spring material is externally fitted by being locked to the inner peripheral stepped portion 18,
Friction and wear between the cylindrical body 20 and the collar 2, so-called galling, can be eliminated. The thin plates 24 and 25 are formed by rolling a strip plate, and the circumferential lengths thereof are the circumferential lengths of the tubular portion 20B and the hitting ring 21, respectively. Incidentally, the hole 23
Shows that it is formed at one place, but it may be provided at two or three places corresponding to the discharge groove 14. Further, in FIG. 3, the sliding plate 24 is shown by a solid line, and the attached state is shown by a chain line. The tubular body 20, the hitting ring 21, and the hole-expanding bit 22 constitute a hole-expanding bit device 26 made of steel or the like.

The hole expanding bit device 26 and the hitting collar 2
The assembling method will be described. As shown in FIG. 3, the striking collar 2 is divided into two in the length direction.
The split collars 2A and 2B are formed by fitting the thin plates 24 and 25 onto the hitting ring 21 and the tubular portion 20B in advance, and the abutment points 27 of the split collars 2A and 2B are welded. The casing pipe 1 is provided on the base end side of the pad collar 2.
And the casing pipe 1 is welded to the base end side of the striking collar 2 by the welded portion 28.

Next, the method of using the excavating device having the above-mentioned structure will be described. As shown in FIG.
The bit head 11 is inserted into the casing pipe 1 to which 26 and the hitting collar 2 are attached, and the bit head 11 projects from the tip of the expanded hole bit 22. Then, when the impact force and the rotational force are transmitted to the device 7 by the drill hammer 5, the bit head 11 moves to the excavation surface K.
It rotates while striking, and at the same time, the outer peripheral step portion 17 of the device 7
Hits the striking ring 21 and the impact force is transmitted to the hole expanding bit 22, and the hole expanding bit 22 hits the excavation surface K as shown in FIG. Further, the outer peripheral step portion 17, the hitting ring 21, and the inner peripheral step portion 18
The impact force is also transmitted to the striking collar 2 via the, and the casing pipe 1 is driven in. This operation is repeated to excavate by hitting and rotating. Further, at the beginning of excavation, the cylindrical body 20 rotates a little due to the friction with the device 7, but the compressed air exhausted from the exhaust port 16 during this rotation causes the vertical groove to move.
13, crushed stones and small gravel along the discharge groove 14 are discharged upward. At this time, a part of the slime S such as crushed stone or small gravel is filled in the hole 23 so that the slime S acts as a connecting pin and the device 7 and the hole expanding bit 22 are integrated with each other. The hole bit 22 is surely driven to rotate.
The bit head 11 and the hole-expanding bit 22 strike the entire excavation surface K, and the hole-expanding bit 22 rotates together with the bit head 11 to perform excavation.

As described above, since the whole excavation surface K is hit by the hole-expanding bit 22 and the bit head 11 and excavates while rotating, the rotational resistance is reduced and the torque can be rotated with a low torque. The wear of the spline groove 9 is small, and the bit head 11 and the hole-expanding bit 22 are not partially worn, so that the durability is improved.

A hole is formed from the bit head 11 to the expanded bit 22.
Rotational force is transmitted by the slime S filled in 23, but when the filled slime S is crushed during the excavation, these crushed crushed stones and small gravel are converted into a flow of compressed air passing through the discharge groove 14. The slime S, which has been pulled upward along this direction and then risen from below, is filled into the hole 23 again, and the slime S causes the bit head 11 to expand the hole.
The rotational force is transmitted to 22.

Then, a predetermined depth, for example, a relatively deep depth, for example, 1
When the excavation of about 00 meters is completed, the bit head 11 is pulled up and collected as shown in FIG.

As described above, in this embodiment, the bit head 11 is provided at the tip of the device 7 which receives the impact force and the rotational force,
An outer peripheral step portion 17 that is an outer step portion is formed on the outer periphery of the device 7, and a striking ring 21 is provided on the cylindrical body 20.
7. Impact force is transmitted to the striking collar 2 through the striking ring 21, and excavation is performed by the impact force and the rotating force of the bit head 11 protruding from the tip of the striking collar 2, and further the device 7 and the striking collar. Cylindrical body 20 that can slide between 2
Since the expansion hole bit 22 having a diameter larger than that of the striking collar 2 is provided at the tip of the cylindrical body 20, the outer peripheral step portion 17 of the device 7 strikes the striking ring 21 to increase the impact force. The hole is transmitted to the hole bit 22, and the hole expanding bit 22 and the bit head 11 strike the entire surface of the excavation surface K for efficient excavation. In addition, the hole expanding bit device that is separate from the device 7
Since the hole diameter is expanded by using 23, the bit device can be simplified and less likely to break, and the member strength can be increased by forming the hole expanding bit 22 into a substantially cylindrical shape. At the same time, the occurrence of partial wear is reduced.

Further, since the device 7 is fitted in the tubular body 20 and the rotational force of the device 7 is transmitted to the hole-expanding bit 22, the entire excavation surface K is excavated by the hole-expanding bit 22 and the bit head 11. The bit head 11 and the hole-expanding bit 22 have a low rotational resistance and can rotate with a low torque. For example, the wear of the rotation transmission part such as the spline groove 9 is reduced, and the bit head 11 and the hole-expanding bit 22 part. Wear is reduced and durability is improved. Further, by disposing the hole-expansion bit 22 behind the bit head 11, the bit head 11 excavates the center of the excavation surface K, and the central excavation portion serves as a guide for expanding the outer peripheral side thereof. Bit 22 can excavate efficiently.

Further, the cylindrical body 20 is provided with a slime filling hole 23 communicating with the discharge groove 14, and the hole 23 is filled with a part of crushed stone and small gravel discharged through the discharge groove 14 into the hole 23. As a result, the device 7 and the cylindrical body 20 having the hole expanding bit 22 can be integrated, and the rotational force can be reliably applied from the device 7 to the hole expanding bit.
Can be transmitted to 22. Moreover, the means for transmitting the rotational force from the device 7 to the hole-expanding bit 22 is performed by the slime S such as crushed stone or small gravel. When the pin is broken, not only the underground device 7 must be pulled up and repaired if the pin is broken, but there is a possibility that the device 7 itself cannot be pulled up depending on the damage condition of the pin. Slime S such as crushed stone and small gravel as described above
By replacing the pin with a pin, it will be automatically regenerated even if the crushed stone, small gravel, or other slime S that has been filled in the hole 23 is damaged. It is possible to eliminate the risk of a failure such as pulling up the device 7 for repair or being unable to pull up the device 7 itself. Moreover, the recess for filling the slime has a through hole 23.
It can be easily manufactured by forming.

A thin plate is provided between the cylindrical body 20 and the collar 2.
Hitting collar 2 and device 7 because 24 and 25 are fitted
Since it can slide, resistance is reduced and torque loss can be reduced.

Further, when the collar 2 and the hole expanding bit device 23 are mounted on the casing pipe 1, the collar 2 is replaced by 2
By forming the divided collars 2A and 2B, and welding the abutment points 27 of the divided collars 2A and 2B,
Easy to make.

The present invention is not limited to the above embodiment, but various modifications can be made within the scope of the gist of the present invention. For example, means for applying an impact force and a rotational force to the device can be appropriately selected. Further, as shown in FIG. 6, the slime filling concave portion may be formed by a concave portion 31. In this case, since the slime S is in contact with the inner side of the concave portion 31, the device 7 and the cylindrical body can be more surely contacted. You can lock 20.

[0020]

According to the invention, a bit head is provided at the tip of a device which receives an impact force and a rotational force and has a discharge groove on the outer periphery,
An outer step portion is formed on the outer periphery of the device, and an inner step portion is provided on the hitting collar provided at the tip of the casing pipe, and an impact force is transmitted to the hitting collar through the step portion, and at the same time, the hitting collar is applied. In an excavating device for excavating by an impact force and a rotational force of the bit head protruding from the tip of a hitting collar, a tubular body is provided between the device and the hitting collar, and the both step portions are provided at the base end of the tubular body. A striking ring arranged between them is provided, and a hole with a diameter larger than the striking collar is provided at the tip of the striking collar of the cylindrical body, and the cylindrical body can communicate with the discharge groove. The excavation device is characterized by having a concave portion for filling slime, which improves the strength of the hole-expanding bit, enables efficient excavation with low torque rotation, and has excellent durability and device. of The rolling force can provide a small rigs trouble is possible reliably transmitted to the cylinder-side.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a bottom view showing an embodiment of the present invention.

FIG. 3 is an exploded perspective view of essential parts showing an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a state in which the bit device according to the embodiment of the present invention is pulled up.

FIG. 5 is a cross-sectional view of a main part showing an embodiment of the present invention.

FIG. 6 is a sectional view showing another embodiment of the present invention.

[Explanation of symbols]

 1 Casing pipe 2 Hitting collar 7 Device 11 Bit head 14 Discharge groove 17 Outer circumferential step (outer step) 18 Inner circumferential step (inner step) 20 Cylindrical body 21 Hitting ring 22 Expanding bit 23 Hole (slime filling) Recess)

Claims (1)

[Claims] 1. A bit head is provided at the tip of a device which receives an impact force and a rotational force and which is provided with a discharge groove on the outer periphery thereof, an outer step portion is formed on the outer periphery of the device, and a striking member provided at the tip of a casing pipe. An excavation device that is provided with an inner step portion on the collar, transmits an impact force to the striking collar through these step portions, and excavates by the impact force and the rotational force of the bit head protruding from the tip of the striking collar. In the above, a tubular body is provided between the device and the hitting collar, and a hitting ring disposed between the both step portions is provided at the base end of the tubular body and protrudes from the hitting collar of the tubular body. An excavating device, characterized in that a hole-expanding bit having a diameter larger than that of the hitting collar is provided at a tip, and a slime-filling recessed portion that is capable of communicating with the discharge groove is provided in the cylindrical body.