JPS59118998A - Drill head in horizontal long distance drilling - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to an excavation head for a long-distance excavation method.

Relatively small diameter pipes such as gas pipes and water pipes on roads with heavy traffic or in urban areas? Trenchless burying methods have been known for burying. This construction method consists of (1) Generally, a pilot pipe is laid from a starting shaft to a destination shaft, and then the main pipe is successively buried along the pilot pipe while enlarging the hole with a drilling head.

Various types of this drilling head have been known, and the present inventor also previously filed a patent application in 1983-
A new drilling head has been proposed as No. 106290. This drilling head is connected to the tip of a pilot pipe that has penetrated to the arrival shaft, and is designed to perform hole expansion while being drawn toward the starting shaft via the pilot pipe.

An excavation bit 'l&: is provided on the pilot pipe connection side, and a discharged soil intake port is formed near the bit, which is rotatably connected to the subsequent buried pipe.

Then, the excavated soil with the bit is poured into the head through the inlet and sent out to the outside.

However, such drilling heads also have one drawback.

That is, when excavating particularly soft ground, too much surrounding earth and sand is taken into the head, which causes the ground wall around the head to collapse, resulting in a ground ratio below (2). For this reason, the inventors of the present invention, in Utility Application No. 56-160327, provided a waste soil intake amount adjustment valve inside the waste soil intake port, supported it with this pulp bispring, and discharged soil according to the soil. We are proposing an excavation head that controls the opening area Y of the soil intake. However, the above-mentioned adjustment of the amount of soil taken in is required to be different depending on the soil type, and for this reason, with the above-mentioned excavation head, which adjusts the intake amount by the pressing force of the spring, it is necessary to adjust the amount of soil taken in according to the soil type. There is a problem in that it must be replaced before use.

The present invention was devised in view of these problems, and it is an object of the present invention to provide an excavation head that can arbitrarily adjust the intake of excavated soil into the head depending on the soil quality and the like.

For this reason, the present invention provides a cylindrical body t1 having a connecting portion with a pilot pipe at its tip and a closed rear end in the head body so as to be pressurized so as to be internally installed on the rear end side or in a hollow part within the head body, A soil intake port is formed in the cylindrical body (3) in the middle part, and a screw rod for transferring the soil in the direction of the pilot pipe is rotatably provided in the longitudinal direction of the cylindrical body. The tip is formed with a connection part for the power transmission rod that is introduced through the pilot pipe 1, and the amount of soil taken into the head body is controlled by adjusting the amount of soil discharged by controlling the rotation speed of the screw rod. This allows for arbitrary adjustment.

Embodiments of the present invention will be described below based on the drawings.

Figures 1 to 3 show one embodiment of the present invention, and in the figures, (a) is an excavation head, and (b) is a planned buried pipe (hereinafter referred to as buried pipe) that will be connected to this excavation head. )
It is.

The drilling head of the present invention includes a head body 1 and a head body 1.
The tube body 2 is rotatably connected to the rear part of the tube body 2.

The head body 1 has an earth removal inlet and a digging bit on its front.
This will be discussed later.

A cylindrical body (4) 4 is provided at the center of the front surface of the head body 1 so that its rear end side is accommodated in the hollow portion 3 within the head body 1. This cylindrical body 4 has its rear end closed 6 with a cap 5 etc., and its tip opened.
A connecting portion 7 (female threaded portion) with the pilot tube is formed at this tip. A cylindrical body 4 within the hollow portion 3 is formed with a soil intake port 8 for taking in the soil discharged from the hollow portion 3 into the cylindrical body 4 .

Further, drilling water (or slurry forming liquid) 9 is formed in the cylindrical body 4 from the rear end side to the front end side, and further from the flow path 9 to the vicinity of the front surface of the bit holding member 27 described below and the front surface of the head main body 1. Injection holes 10 and 11 each extending nearby
is provided.

along the longitudinal direction inside the cylindrical body 4 in the pilot pipe direction (first
Screw rod 12 for unloading soil and transferring it to the left side in the figure
is rotatably provided. One end of the screw rod 12 is supported by a bearing 13 located at the rear end inside the cylindrical body 4. In this embodiment, the screw rod 12 has a double tube structure consisting of an inner tube 121 and an outer tube 122,
A screw 14 is provided in the longitudinal direction of the outer surface of the outer tube 122.

The inner tube 121 is inserted into the outer tube 122 with a suitable gap 5), and both are integrally connected by a holding member 15 with holes. The gap and the inside of the inner pipe 121 are configured with channels 16 and 17yIl for water, etc., respectively, and water for slurry transportation flows in the channel 16, and drilling water (or slurry forming liquid) flows in the channel 17. do. The rear end of the outer tube 122 is closed 19 via the cap 18, and the inner tube 121 protrudes from the closed rear end, and this protrusion is supported by the bearing 13. This bearing 13 and the closed part 6 at the rear end of the cylindrical body
A space 20 is formed therebetween, and the end of the inner tube 121 protrudes from the bearing 13 into this space 20, so that a fluid such as water can be discharged into this space 20 through the inner tube 121. In this embodiment, a cap 21 in which a discharge port 211 is formed is attached to the end of the inner tube 121 protruding from the bearing, and this cap 21 prevents the inner tube from coming off. Further, near the terminal end of the screw 14 on the distal end side of the outer tube 122, an injection nozzle 22 configured to inject water in the direction of the high-speed tube is provided, and the water supplied through the flow path 16 is The liquid is sprayed from the nozzle 22 toward the piset (6) inside the cylindrical body 4. Fluids such as water are separately supplied to the flow paths 16 and 17 of the screw rod 12 from the starting shaft side of the pilot pipe (c), and the screw rod 12 is introduced from the starting shaft side through the pilot pipe. It is rotated by the rotational driving force of the power transmission rod, and for this reason, connecting portions 23 and 24 (female screw portions) are formed at the tips of the inner tube 121 and the outer tube 122, respectively. The power transmission rod (which is introduced from the starting shaft side through the pilot pipe 7) is connected to the inner pipe (knee 1) and the outer pipe (knee 2).
), each of which is comprised of the screw rod 1
It is connected to the inner tube 121 and outer tube 122 of No. 2.

In addition, to explain the other configuration of this embodiment, in this embodiment, if gravel gets caught in the waste soil intake port for taking the waste soil into the head body, there is a mechanism for removing it. For this purpose, a mounting hole 25 is provided in the center of the front surface of the head body 1 while forming a guide cylinder part 26, and the cylindrical body 4 can move forward and backward in the axial direction of the head body. (7) It is inserted. In this embodiment, the cylindrical body 4 has a spline shaft shape, and is prevented from rotating in the circumferential direction by being fitted into the mounting hole 25.

A hood-shaped bit holding member 27 is attached to the cylindrical body 4 and has a shape substantially corresponding to the front end of the head body. The bit holding member 27 has a tapered front surface and a short tubular skirt portion 28 at the rear, and the inner circumferential surface of the skirt portion 28 slides on the circumferential surface of the head body 1 in the longitudinal direction of the head body. possible contact. The circumferential surface on the tip side of the head body 1 that the skirt portion 28 comes into contact with is configured to have a smaller diameter than the main body portion in order to absorb the thickness of the skirt portion 2B.

Several excavation bits 29 are provided in the radial direction on the front surface of the bit holding member 27, and a slit-shaped soil intake port 30a for taking in the discharged soil Y into the inside of the bit holding member 27 is provided near each of the digging bits 29. (It is provided facing in the radial direction. Also, a slit-shaped soil discharge intake port 30b facing in the radial direction is provided on the front surface of the head main body 1. The soil intake port 30a and the soil discharge port 30b of the head main body 1 are provided with their positions shifted in the circumferential direction.

Projecting members 31b and 31a are provided on the front surface of the head main body 1 and the back surface of the bit holding member 27 so as to face the discharging soil intake port of the bit holding member 27 and the discharging soil intake port of the head main body 1, respectively. , by retracting the bit holding member 27 toward the head body, each protruding member 31a, 31b and the opposing soil intake inlet 30 are removed.
b, K so that it can be pushed into 30a. In this embodiment, the protruding members 31a and 31b are made of plate-like bodies.

The tube body 2 is rotatably connected to the rear end of the head body 1 via a rotary joint 33. That is, a shaft body 32 is provided at the rear of the head body 1, and this shaft body 32Y is pivotally supported within the tube body 2 by a bearing constituting a rotary joint 33, so that the head body 1 and the tube body 2 are mutually connected. Rotatably connected. In addition, there is a buried pipe (b) at the rear end of this pipe body 2.
are connected by welding etc.

(9) FIG. 4 shows another embodiment of the present invention. In the embodiment described above, slurry transport water and drilling water (or slurry making liquid) are each sent from the starting shaft side through the pilot pipe 7. In contrast, in the embodiment,
Water for transporting slurry was supplied through a high-lot pipe, and water for drilling (water for slurry conversion) was supplied from the reaching shaft side through an underground pipe.
The screw rod 12' has a single tube structure and is supported by a bearing 13' provided at the rearmost end of the cylindrical body 4. The inside of the screw rod 12' is hollow, and water for slurry transportation can be supplied thereto, and this water for slurry transportation is directed from the injection nozzle 22 near the end of the screw on the tip side of the rod to the pilot pipe inside the cylindrical body 4. It is designed to be injected into the air. At the tip of the screw rod 12', there is provided a connecting portion 24' (female threaded portion) for making a Y connection (to a tubular power transmission rod introduced through the pilot pipe (c)). The cylindrical body 4 has a flow path 9' (for drilling water (or slurry) from the rear end side to the front end side K, as in the previous embodiment.
10) is formed, and water injection holes 10 and 11 are provided extending from the flow path 9' near the front surface of the bit holding member 27 and near the front surface of the head body 1, respectively. A supply pipe 34 introduced from the reaching shaft side is connected. This supply pipe 34 is led into the head body 1 through the hollow part 321 of the shaft body 32, and its tip is connected to the rear end of the cylindrical body 4 so as to communicate with the flow path 9'. The head body 1 is connected to the tube body 2V via the swivel joint 33Y.
In order to rotate with respect to c, a rotary joint 35 is interposed in the middle of the supply pipe 34, and a pipe portion 341 on the side of the head main body from the rotary joint 35 is supported by a support member 36 in the shaft body 32, and a pipe portion 341 on the side of the pipe body The tube portion 342 is supported by the support portion 37 within the tube body 2, and only the tube portion 341 is extended to rotate together with the head body 1. A portion of the tube portion 341 is a flexible tube. The other configurations are substantially the same as those shown in FIGS. 1 to 3.

In each of the above embodiments, a Tonosho detector 38 is provided in the hollow part 3 in the head body, and the earth pressure inside the hollow part 3 is detected 1-1 based on the detection result.
The rotation speed is controlled 7 to adjust the amount Y of discharged earth in the direction of the pilot pipe.

In the above embodiment, the soil is slurried with transportation water and transferred into the pilot pipe, but there is also a method in which the soil is slurried with transport water and transferred into the pilot pipe. It is also possible to transport it.

In the Mata example, separate supply systems are provided for the slurry transportation water and the slurry-forming liquid such as bentonite, as it is necessary to supply them separately. In the case of equipment, water supply system '7
It is also possible to have a structure in which the supply system is integrated into one and distributed to the necessary locations from this supply system. For example, in the case shown in Fig. 1, the water supply system is unified as a single pipe structure with 12 screw rods as shown in Fig. 4,
It is also possible to apply pressure so as to form an injection hole that communicates with the inside of the cylindrical body 4 from the tip of the flow path 9 .

Next, the operation of the present invention will be explained.

The drilling head (A) of the present invention is attached to the tip of a pipe (C) that penetrates from the starting shaft (A) to the reaching shaft (B) as shown in FIG. The tip of the main body of the pilot tube (C) is screwed into the connection part of the screw rod 12 protruding from the cylindrical body 4.
The tip of the power transmission rod introduced through the pilot pipe 7 is screwed into the connecting portion of the power transmission rod. The drilling bit 29 installed in this way is pulled into the starting shaft (ltllK) by the pilot pipe ←→, and in this process, hole expansion drilling and management installation are performed. That is, the drilling head (a)
Only the head body 1 is rotated and pulled by the pilot pipe (c) which is rotated and retreated toward the starting shaft by the driving force of 0, and the ground is expanded and excavated by the drilling bit 29 on the front side. The pipe body 2 carries the buried pipe (b) at its rear part, and follows the head body 1 in a non-rotating state due to the action of the rotary joint 33. The buried pipe (B) led to the excavation head (A) is added on the reaching shaft (B) side as the head advances, and the excavation head (A) reaches the starting chamber (13) on the shaft (A) side. This completes the burial. In addition, in such a management installation process, the rear end χ of the buried pipe (B) may be suppressed by a suppression device on the reaching shaft (Bl side) to supplement the propulsive force of the buried pipe (B). By using the above suppression device, excavation is performed so that a gap is created between the buried pipe and the soil wall of the excavation hole, and an anti-friction agent is injected into this gap to reduce the peripheral surface resistance with the soil wall. You can be pressured to do a side-drill excavation.

The soil produced by excavation is first taken into the inner space 39 from the soil intake port 30a of the bit holding member 27, and
Further, the soil is guided into the hollow part 3 in the main body from the unloaded soil intake port 30b on the front surface of the head main body 1. The discharged soil in the hollow part 3 is further guided into the cylindrical body 4 through the discharged soil intake port 81, and the screw rod 12 rotates in the opposite direction to the rotational direction of the head body by the rotational driving force generated by the power transmission rod. It is transferred by the screw 14 in the direction of the pilot tube. The soil is sent out from near the end of the screw 14 to the pilot pipe (C) (14) by water for transporting the soil discharged from the injection nozzle 23. Note that the power transmission rod) rotates in the opposite direction to the rotation direction of the pilot tube (c), and is not held in the pilot tube (c) (because it is simply inserted). , the pilot pipe (c) generates a swirling motion along the inner circumferential direction, and the stirring effect of this swirling motion on the discharged soil prevents heavy soil from settling inside the pilot pipe, making it easier to feed the discharged soil with transportation water. In the process of excavation and soil discharge, which are carried out extremely smoothly and reliably, the excavation head of the present invention can adjust the amount of soil taken in according to the soil quality of the ground to be excavated. The discharged soil enters the cylindrical body 4 from the hollow part 3 of the head body through the discharged soil intake port 8v, and is transferred from there toward the pilot pipe by the screw rod 12, but the rotation speed of the screw rod 12 is controlled. This is to form a compacted state in the excavated earth in the hollow part 3, and to regulate the amount of excavated earth taken into the hollow part 3.Generally, in the case of soft ground such as sand, the excavated earth in the hollow part 3 is There is a tendency for too much soil to be taken in, causing soil wall collapse and ground subsidence; in such cases, the number of revolutions of the screw rod 12 should be lowered to reduce the amount of soil taken into the cylindrical body 4. As a result, the excavated earth in the hollow part 3 is in a consolidated state,
The amount of soil taken in from the soil intake port 30b of the head body is reduced. On the other hand, when the ground is relatively hard, the number of revolutions of the screw rod 12 can be increased to take in the removed earth in a way that matches the excavation efficiency. In addition, it is preferable that such rotation speed control is performed based on the detection result by the earth pressure detector 38 in the hollow part 3.

Also, as mentioned above, during excavation, if the ground is relatively hard,
Through the channel 9 or 9'Z, drilling water is supplied from the injection holes 10 and 11 into the face of the drilling bit 29 and into the space 39, whereby the discharge is slurried and taken into the head body. On the other hand, if the excavated ground is soft and contains a large amount of moisture, such as an aquifer sand layer,
A slurry-forming liquid such as bentonite liquid is supplied from the injection hole 10.11 to add viscosity to the discharged soil and take in the discharged soil, thereby controlling the rotation speed by the screw shaft. In this way, the inside of the hollow part 3 is brought into a compacted state, and collapse of the earth wall, etc. can be prevented.

In addition, in the case shown in FIG. 1, the drilling water or slurry-forming liquid such as bentonite is supplied to the inner pipe (knee 1) of the power transmission rod and the inner pipe 121 of the screw rod connected thereto.
It is fed from the starting shaft side to the flow path 9 through the
In the case shown in the figure, it is communicated with the supply pipe 34 and is fed from the reaching shaft side to the flow path 9'. In both cases of Fig. 1 and Fig. 4, the screw rod is Water for slurry transport is supplied into the slurry 12 and is jetted from the jet nozzle 22.

In addition, to explain other effects, in the process of excavation mentioned above, if gravel etc. gets stuck in the soil intake ports 30a and 30b and becomes clogged, the excavation is temporarily stopped and the Push the pilot tube (c) back in the direction of the drilling head (a). As a result, the cylindrical body 4 is attached to the mounting hole 25.
slides inward into the head main body, and along with this, each of the protruding members 31b and 31a opens the discharging soil intake port 30a facing each other.
, 30b and the bits that are bitten (17) are pushed out to the outside of the bit holding member or into the head body. After that, by pulling the pilot tube (c), the cylindrical body 4 will slide to its original position.

Excavation can be resumed in this state.

According to the present invention described above, the head main body 1 having the excavation bit and the soil removal tube on the front side, the cylindrical body 4 having the connecting part Z with the pilot pipe at the tip and having the rear end closed 6, is then attached. The hollow part 3 in the head body 1 is provided at the end side, and eight soil intake ports are formed in the cylindrical body 4 in the hollow part 3. A screw rod 12 for discharging in the direction of the pipe is rotatably provided, and a connecting part Z for a power transmission rod introduced through the pilot pipe 7 is formed at the tip of the screw rod 12. By adjusting the amount of soil taken in and transferred in the direction of the pilot pipe by controlling the rotation speed, it is possible to form a consolidated state within the head body, and even when the excavated ground is particularly soft, the head body This has the effect of regulating the amount of soil taken into the soil, thereby allowing for underground excavation7 to be carried out without causing collapse of soil walls or poor soil quality.

[Brief explanation of drawings]

1 to 3 show an embodiment of the present invention,
FIG. 1 is a longitudinal sectional view, FIG. 2 is a sectional view taken along line 1--2 in FIG. 1, and FIG. 3 is a front view of the head body in a cross-sectional state of the cylindrical body. FIG. 4 is a longitudinal sectional view showing another embodiment of the present invention. FIG. 5 is an explanatory diagram showing the excavation situation by the excavation head of the present invention. In the figure, 1 is the head body, 2 is the tube body, 3 is the hollow part,
4 is a cylindrical body, 6 is a closing part, 7 is a connecting part, 8 is a discharged soil intake port, 12, 12' are screw rods, 23° 24, 24
' is a connection part, 29 is a drilling bit, and 30a. 30b announces the soil intake location. Patent applicant: Tokyo Gas Co., Ltd., Nippon Steel Tube Co., Ltd., Koken Test Drilling Co., Ltd. (19) 1-29-15 Chuo, Nakano-ku, Tokyo

Claims (1)

[Claims] The head body has a drilling bit and discharge intake tube on the front, a cylindrical body χ with a pilot pipe connection at the tip and a closed rear end, which is installed on the rear end side or inside the inner wall of the head body. In addition, a discharged soil intake port is formed in the cylindrical body inside the inner part, and a screw rod for discharging the soil in the direction of the pilot pipe is rotatably provided in the longitudinal direction of the cylindrical body. An excavation head used in the horizontal long-distance excavation method, in which the tip of the screw rod is connected to a power transmission rod that is introduced through the pilot pipe.