JPH11222846A - Pit expanding type soil improving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pit expanding type soil improving device, by which excavation at an original place with high accuracy is carried out and which has a large expansion-contraction range in the soil improving device. SOLUTION: Cylinders 11a, 11b and a piston 12 are incorporated to the front end section of a triple rod 1, a shoe 5 is installed at the front end of the triple rod 1, an end bit 6 is mounted movably to the shoe 5 and the end pit 6 is connected to the piston 12. A pin 8 fixed onto the shoe 5 is penetrated into the stroke hole 7 of the end bit 6, pit-expanding bits 9 are set up to the pin 8 and the pit-expanding bits 9 are fitted to the nose bit 6 through expansion- contraction links 10. The nose bit is moved while being interlocked with the piston by high-pressure water, and the expansion-contraction links are operated and the pit-expanding bits 9 are expanded and contacted centering around the pin 8. A solidifying agent is discharged from the front ends of the pit- expanding bits and agitated, and a solidifying layer is formed in a ground. Load to the pit-expanding bits can be equalized, and excavation is carried out at an accurate place. The pit-expanding type soil improving device is compacted because the piston is incorporated, and a malfunction is not also generated because of simple structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soil improvement device, and more particularly, to a hole improvement type soil improvement device capable of performing a wide range of improvement using a widening device.

[0002]

2. Description of the Related Art Improvement of the ground is carried out by injecting and stirring a solidifying agent such as a chemical solution or cement milk into a soft layer in the ground and solidifying the soft layer to form a consolidated layer in the ground.
In this case, an elongated flat wide bit is provided at the tip of the excavator so that the improvement range of the soft layer can be partially expanded. A conventional bit is provided with a rotary drive shaft having a gear at the lower end of a drilling column, and the center of an elongated bit is mounted on the horizontal axis. By this horizontal axis rotation, both ends of the bit protrude into the ground from above and below the drilling rod. It has become. (For example, see Japanese Utility Model Publication No. 1-8589)

[0003]

However, in the above conventional example, when the bit is widened in the ground, when both ends of the widened bit protrude into the ground, the upper end extends, for example, to the right from above the horizontal axis. Then, the lower end comes out to the left below the horizontal axis, and the load applied to the excavator is biased due to the rotation, so that there is a problem that the position in the ground shifts. In addition, the widening structure is complicated and there is a risk of malfunction.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a compact open hole type soil improvement device for a base machine which can improve the ground by high-precision in-situ excavation without bias, has a simple structure and does not malfunction. .

[0005]

The above object is achieved as follows. The expanded soil improvement device according to claim 1 is
A piston built in an expansion and contraction device provided at the tip of the ground excavation rod, a tip bit connected to the piston and having a stroke hole, a shoe provided at the tip of the expansion and contraction device, And an expansion bit attached to the shoe via a pin to be mounted and attached to the tip bit via an expansion / contraction link, and the expansion / contraction link operates by movement of the tip bit in conjunction with the piston. Thereby, the expansion and contraction of the hole expanding bit is performed. According to this device, the load applied to the hole expansion bit is not biased,
High-precision ex-situ excavation becomes possible. The apparatus according to claim 2, wherein the ground excavation rod has at least three lines of a passage for a solidifying agent used for improving the ground, a fluid passage for pushing up the piston, and a fluid passage for pushing down the piston. , The piston at the rod tip can be easily operated by, for example, water pressure. Further, in the apparatus according to the third aspect, since a discharge port of a solidifying agent used for ground improvement is formed at a tip portion or the like of the hole expanding bit, the mixing and mixing of the solidifying agent and the earth and sand can be easily performed.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show an embodiment of the expanded soil improvement apparatus of the present invention. FIG. 1 is a longitudinal sectional view of the lower part of the rod when the diameter of the expanded bit is enlarged, and FIG. 2 is a longitudinal sectional view of the upper part of the rod. is there. FIG. 3 is a view of the hole-expanding bit in FIG. 1 as viewed from an arrow A, FIG. 4 is a longitudinal sectional view of the lower part of the rod when the hole-expanding bit is reduced in diameter, FIG. 5 is a side view of FIG. It is an arrow view.

FIG. 1 shows a main part of this embodiment.
The triple pipe rod 1 is composed of an outer pipe 2, an inner pipe 3, and a hollow center rod 4, and an expansion / contraction device 19 is provided at the tip of the triple pipe rod 1. Hereinafter, the expansion and contraction device 19 will be described in detail. A tip shoe 5 is attached to the tip of the triple tube rod 1, and a tip bit 6 connected to the hollow center rod 4 is attached to the tip shoe 5. This tip bit 6 is provided with a long stroke hole 7,
A fixing pin 8 fixed to the tip shoe 5 is inserted through the stroke hole 7. The fixed pin 8 supports two wing-shaped expanding bits 9, and the expanding bit 9 is attached to the tip bit 6 via an expanding / reducing link 10. As a result, when the leading end bit 6 is raised, the expanding / reducing link 10 is operated to expand the diameter of the hole expanding bit 9 around the fixing pin 8, and when the leading end bit 6 is lowered, the diameter of the hole expanding bit 9 is reduced. The operating range is regulated by the length of the stroke hole 7, and by abutting the end of the stroke hole 7, positioning at the time of diameter expansion and contraction can be easily performed.

A cylinder 11 is provided inside the inner tube 3 inside the triple pipe rod 1 above the tip shoe 5, and a piston 12 provided on the hollow center rod 4 is arranged inside the cylinder 11. , Piston 12 is connected to tip bit 6 via cylinder rod 13. The tip bit 6 is moved up and down by the vertical movement of the piston 12, and the expansion bit 9 is expanded and contracted. In addition, the hole expansion bit 9 has
The metal 18 having excellent wear resistance is integrated.

The up-and-down movement of the piston 12 includes hydraulic pressure, hydraulic pressure,
This is based on fluid pressure such as air pressure, and in this embodiment, high-pressure water is used. The diameter expanding operation of the hole expanding bit 9, that is, the operation of moving the piston 12 upward, drains water in the upper cylinder chamber 11 a above the piston from the flow passage 14 between the inner pipe 3 and the center rod 4, and at the same time, hollows out the water. High-pressure water is circulated in the hollow 15 of the center rod 4 to inject water into the lower cylinder chamber 11b below the piston, and the piston 12 is moved upward using the water pressure. Conversely, the operation of expanding and contracting the hole expanding bit 9, that is, the operation of moving the piston downward, drains the water of the lower cylinder chamber 11b from the hollow 15 of the center rod 4 and removes the water of the upper cylinder chamber 11b.
a, high-pressure water is injected from the flow passage 14 to push down the piston 12 downward. As described above, the expansion and contraction of the hole expanding bit can be performed very easily. The gap 16 between the outer tube 2 and the inner tube 3 serves as an injection path for a chemical such as a solidifying agent, cement milk, mortar, or the like. From the ground.

As shown in FIG. 2, a water swivel 20 is mounted on the upper part of the triple pipe rod 1, and a hydraulic chuck 21 for gripping the hollow center rod 4 is further mounted thereon. Water swivel 20
A high-pressure water supply port 14a for reducing the diameter of a perforated bit is provided to be connected to the flow path 14, and an injection port 16a for a chemical solution or the like is provided to be connected to the flow path 16. The end of the hollow path 15 of the center rod 4 is a high-pressure water supply port 15a for expanding the diameter of the hole-extending bit. As shown in FIG. 7, the triple tube rod 1 is gripped by the rotation driving device 33 provided on the leader 31 at the intermediate portion of the triple tube rod 1, and the tip bit 6 provides the rotation force and the propulsion force. Is given.

FIG. 3 is a view of the hole expanding bit shown in FIG. The two expansion bits 9 are attached to both outer sides of the tip bit 6 via expansion links 10. The diameter of the hole-expanding bit 9 is increased while rotating and pulling up the triple tube rod 1. The expanding bit 9 rotates substantially horizontally with the triple pipe rod 1 in a state where the diameter is expanded, and agitates the ground while discharging a solidifying agent or the like from a discharge port 17 at a distal end portion.

FIG. 4 is a longitudinal sectional view of the lower part of the rod when the diameter of the hole is reduced, FIG. 5 is a side view of FIG. 4, and FIG. 6 is a view taken in the direction of arrow B in FIG. As shown in these figures, the upper cylinder chamber 11a in the triple pipe rod 1 is filled with high-pressure water, and the piston 12 is pushed downward. Tip bit 6 connected to piston 12 via cylinder rod 13
In the state where the inside of the tip shoe 5 is pushed down and the fixing pin 8 is in contact with the upper end of the stroke hole 7 by the operation of the link 10 for expansion and contraction, the diameter of the expanded bit 9 is reduced within the width of the expansion and contraction device 19. It is stored in. In this example, the expansion / contraction device 19 and the triple tube rod 1 are shown integrally,
Actually, they are connected by screws or the like. Further, as shown in FIG. 1, a part of the expansion / contraction device is constituted by a triple tube, and is driven by a triple tube rod.

According to this embodiment, as compared with the conventional example,
Since there is no bias in how the load is applied, the position of the tip bit and the excavation position can be maintained with high accuracy, and there is no malfunction due to the simple structure. Further, by detecting the amount of movement of the center rod, the degree of wing expansion of the hole expansion bit can be known, and the wing expansion bit can be fixed at an arbitrary position. In addition, since the piston cylinder is built in the triple tube rod, the water swivel can be made more compact, and the center rod can be made smaller.

FIG. 7 and FIG. 8 are configuration diagrams showing a state of a hole type ground improvement work to which an embodiment of the present invention is applied. As shown in these figures, the reader 31 is fixed at a predetermined position on the ground 32 by the base machine 30. The intermediate portion of the triple tube rod 1 is gripped by a chuck (not shown) of a rotation driving device 33 capable of moving the reader 31 up and down, and is provided with a rotational force and a propulsive force. The distal end of the triple tube rod 1 is the expansion / contraction device 19 shown in FIG. The triple tube rod 1 is dug into the ground by the rotation drive device 33, and as described above, the diameter of the drill bit 9 is increased while rotating, and the ground is agitated while the cement milk or the like is being injected while a certain range 34 is set. Implement ground improvement. By repeating the excavation and agitation while wrapping the area 34, a wide range of ground improvement is performed. Although the device of the present invention is suitable for ground improvement, it is needless to say that the device of the present invention can be applied to, for example, an anchor excavation hole.

[0015]

As described above, according to the present invention, an excavation bit using an expansion / contraction link enables high-precision in-situ excavation without bias, and, for example, a piston cylinder using water pressure is built in a rod. Accordingly, the drilling device can be made compact with a simple structure and without malfunction, and a drilling type soil improvement device with a large range of expansion and contraction of the expansion and contraction bit can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a lower part of a rod when a hole diameter of a hole is enlarged, according to an embodiment of the hole-expanding type soil improvement device of the present invention.

FIG. 2 is a longitudinal sectional view of the upper part of the rod of FIG.

FIG. 3 is a view as viewed from an arrow A of the hole expanding bit of FIG. 1;

FIG. 4 is a longitudinal sectional view of a lower portion of the rod when the diameter of the enlarged bit is reduced in FIG. 1;

FIG. 5 is a side view of FIG. 4;

FIG. 6 is a view as viewed in the direction of arrow B in FIG. 4;

FIG. 7 is an overall configuration diagram of a hole type ground improvement work to which an embodiment of the present invention is applied.

FIG. 8 is an explanatory view showing a state of excavation and agitation at the time of diameter expansion by the hole expansion bit of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Triple pipe rod 2 Outer pipe 3 Inner pipe 4 Hollow center rod 5 Tip shoe 6 Tip bit 7 Stroke hole 8 Fixing pin 9 Expanding bit 10 Expansion link 11 Cylinder 11a Upper cylinder chamber 11b Lower cylinder chamber 12 Piston 13 Cylinder rod 14 High-pressure water flow path 14a High-pressure water supply port 15 High-pressure water flow path 15a High-pressure water supply port 16 Chemical liquid flow path 16a Chemical liquid inlet 17 Chemical liquid discharge port 18 Metal 19 Expansion / contraction device 20 Water swivel 21 Hydraulic chuck 30 Base machine 31 Leader 32 Ground 33 Rotation drive Equipment 34 Underground stirring range

Continued on the front page (72) Inventor Nobuhiro Kamei 1-6-17 Meguro, Meguro-ku, Tokyo Toneuchi Co., Ltd. (72) Inventor Tetsuo Kawato 4-35, Kudankita 4-chome, Chiyoda-ku, Tokyo Lighting Industrial Co., Ltd. Within the company (72) Inventor Nobuyuki Fujisawa 4-35, Kudankita, Chiyoda-ku, Tokyo Light Industry Co., Ltd. (72) Inventor Takashi Endo 4-2-35, Kudankita, Chiyoda-ku, Tokyo Light Industrial Co., Ltd. In company

Claims (3)

[Claims] 1. A piston built in an expansion / contraction device provided at the tip of a ground excavation rod, and connected to the piston,
A tip bit having a stroke hole, a shoe provided at the tip of the expansion and contraction device, and attached to the shoe via a pin penetrating the stroke hole, and attached to the tip bit via a scaling link. A hole-expanding ground improvement apparatus, comprising: a hole-expanding bit, wherein the expansion / contraction link is operated by movement of a tip bit interlocked with the piston, thereby expanding and contracting the hole-expanding bit. 2. The ground excavation rod includes a passage for a solidifying agent used for improving the ground, a fluid passage for pushing up the piston, and a fluid passage for pushing down the piston.
2. The soil improvement device according to claim 1, wherein the soil improvement device has at least three lines. 3. The expansion type soil improvement device according to claim 1, wherein a discharge port of a solidifying agent used for ground improvement is formed in the expansion bit.