JPH1136784A - Pneumatic impact-type driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To excavate the hard ground and pebbles ground efficiently, and drive a small diameter buried pipe, and also discharge excavated soil and sand effectively by discharging exhausted air given for the operation of an air hammer drill on the ground. SOLUTION: A screw pipe is housed as a driving shaft in the interior part of a casing piercing through the buried pipe and leading pipe 14 to thus be connected a bit 26 of the air hammer drill 22 provided at the tip end of the leading pipe 14. Then, by rotating the screw pipe, the bit 26 is rotated for supplying mud water in the excavation part through the interior part of the screw pipe. Excavated soil and sand is transported by a blade 68 of the screw pipe 68B and exhausted through the interior part of the casing. a supplied air for operating a piston of the air hammer drill 22 is supplied from the ground via an air supply passage 24a and then exhausted above the ground via an exhaust passage 24d.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatic impact propulsion device, and more particularly to a pneumatic impact propulsion device for propelling a small-diameter buried pipe.

[0002]

2. Description of the Related Art Conventionally, as a propulsion device for a buried pipe used for a stratum including clay, boulders, rock and the like or a clay soil layer, there is a shield propulsion device disclosed by the present applicant in Japanese Patent Publication No. 4-13519. . In this shield propulsion device, an air hammer drill is provided at the tip of a shield tube, and the face is crushed and excavated by hitting and rotating with a bit of the air hammer drill.

[0003]

However, in the shield machine described in Japanese Patent Publication No. 4-13519, the diameter of the shield tube is relatively large because the motor for rotating the bit is housed in the shield tube. However, there is a problem that it cannot be used as a propulsion device for a small-diameter buried pipe.

[0004] Further, since the discharge passage for the excavated earth and sand crushed by the bit is provided between the air hammer drill and the shield pipe, the diameter of the discharge passage becomes relatively small, and the excavated earth and sand cannot be discharged efficiently. there were. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a pneumatic impact type propulsion device capable of propelling a small-diameter buried pipe and efficiently discharging excavated earth and sand. And

[0005]

In order to achieve the above object, the present invention comprises a casing fixed to a leading pipe leading a buried pipe, and having a casing penetrating the leading pipe and a central portion of the buried pipe. In the propulsion method of embedding the pipe by applying a thrust to the buried pipe, the tip is rotatably supported by the leading pipe, has a rotatable bit at the tip, is formed hollow at the center, and supplies air. An air hammer drill having air and exhaust passages, a drive shaft disposed in the casing and penetrating through a center portion of the air hammer drill, and transmitting a rotational force to the bit; An air supply line for operating a piston of the hammer drill, and an exhaust line for air provided in the casing and used for operating the piston of the air hammer drill. Characterized in that it consists of.

According to the present invention, the ground is excavated by crushing the face face by hitting and rotating with a bit of an air hammer drill. The piston of the air hammer drill is operated by air supplied from an air supply line, and the air used for the operation is exhausted to the ground via an exhaust line without being discharged into a hole. Excavated earth and sand is discharged through the inside of the casing by rotation of a screw pipe as a drive shaft.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a pneumatic impact type propulsion device according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is an overall configuration diagram of an embodiment of a pneumatic impact propulsion device according to the present invention. As shown in FIG. 1, the pneumatic impact type propulsion device 10 includes a leading conduit 14 leading a buried pipe 12.
And a propulsion device 16 for propelling the conduit 14 ahead.

As shown in FIG. 2, the leading conduit 14 is formed in a tubular shape, and an air hammer drill 22 is provided at its tip via seals 18 and 20 so as to be able to swing.
As shown in FIG. 7, the air hammer drill 22 includes a hammer case 24, a bit 26, and a piston 28 as main components. The hammer case 24 is formed in a double cylindrical shape composed of an outer cylinder 24A and an inner cylinder 24B, and is supported at the distal end of the front conduit 14 via a spherical seat 30 so as to be able to swing freely. And this hammer case 24
The hammer drill 2 by tilting the
2 inclines in the desired direction.

The inclination angle of the hammer case 24 is adjusted using a steering jack as follows. At the rear end of the hammer case 24, three steering jacks 32, 32, 32 are arranged at equal intervals (see FIG. 3), and the hammer case 24 includes the three steering jacks 32, 32, 32 via conduit 32
4. The hammer case 24 is tilted in a desired direction by individually expanding and contracting the three steering jacks 32, 32, 32.

The bit 26 is formed in a hollow shape, and is rotatably supported inside a distal end of the outer cylinder 24 of the hammer case 24 via a seal 34. The hollow portion 26A of the bit 26 has the hammer case 24
Of the inner cylinder 24B is fitted through a seal 36. The tip of the bit 26 is formed so as to protrude from the tip of the hammer case 24, and the outer diameter of the tip is formed larger than the outer diameter of the hammer case 24.

A large number of metal chips 38, 38,... Are implanted on the tip end surface of the bit 26. The metal chips 38, 38,.
The ground is excavated. Further, at the tip of the bit 26, discharging ports 40, 40, which communicate with the internal hollow portion 26A,
Are formed, and the excavated earth and sand is taken into the hollow portion 26A through the discharge ports 40, 40,.

The piston 28 is formed in a cylindrical shape, and is slidably housed between the outer cylinder 24A and the inner cylinder 24B of the hammer case 24. By operating the piston 28, the rear end face of the bit 26 is hit, and the bit vibrates. Here, the operation principle of the piston 28 will be described. As shown in FIG. 7, the hammer case 24 is provided with an air supply passage 2 to which compressed air is supplied.
4a are formed. When the compressed air is supplied to the air supply passage 24a, the compressed air is first guided to the air supply port 24b, and then the outer peripheral groove 28a formed on the outer peripheral surface of the piston 28 in an annular shape, and the outer periphery of the hammer case 24. Through a first vertical groove 24c formed on the inner surface of the cylinder 24A, the piston 28
To the first pressure chamber 42 provided at the front end of the first pressure chamber.
When the pressure air is guided to the first pressure chamber 42, the piston 28 moves rearward via the valve 27 fixed to the bit 26.

When the piston 28 moves rearward, the first pressure chamber 42 is opened. The pressure air supplied to the first pressure chamber 42 is guided to an exhaust path 28 b formed in an annular shape on the inner periphery of the piston 28, and the exhaust path 2
8b from the air exhaust passage 24 formed in the hammer case 24
f, exhausted through 24d. When the pressure air is exhausted, at the same time, the pressure air
A second pressure provided at the rear end of the piston 28 through an outer peripheral groove 28a formed in an annular shape on the outer peripheral surface of the piston 28 and a second vertical groove 24e formed on the inner surface of the outer cylinder 24A of the hammer case 24. It is led to the chamber 44. And, this second pressure chamber 4
When the compressed air is guided to 4, the piston 28 moves forward (the state of FIG. 7).

When the piston 28 moves forward, the second pressure chamber 44 is opened. And this second
The pressure air supplied to the pressure chamber 44 is supplied to the hammer case 24.
The air is exhausted through the air exhaust passages 24f and 24d formed in the air passage. By repeating the above operation, the piston 28 vibrates and the bit 26 is hit.

In order to operate the piston 28, it is necessary to alternately supply and exhaust pressure air to the first pressure chamber 42 and the second pressure chamber 44 as described above. The supply and exhaust of the compressed air are performed as follows.
First, the supply of compressed air will be described. As shown in FIG. 5, an air supply passage 2 formed in the hammer case 24 is provided.
An air supply connection pipe 46 is swingably connected to 4a via a seal 48a. The air supply connection pipe 46 is provided with a seal 48 in an air air supply passage 14a formed integrally with the leading conduit 14.
B is swingably connected via b. The air supply passage 14a is connected to an air supply pipe 50 formed integrally with a casing described later.

The air supply pipe 50 is connected to a joint 52 shown in FIG. The joint 52 has a compressor 56 installed on the ground via an air supply hose 54.
Are connected. By driving the compressor 56, the compressed air is supplied to the air supply passage 24 a of the hammer case 24 via the supply hose 54, the supply tube 50, the air supply passage 14 a, and the supply connection tube 46. You.

Note that, as shown in FIG.
Is connected to an oiler 67, and lubricating oil is supplied from the oiler 67 along with pressurized air. next,
Exhaust of the pressure air supplied as described above will be described. As shown in FIG. 5, an exhaust connection pipe 58 is provided with a seal 6 in an air exhaust path 24d formed in the hammer case 24.
Oa is swingably connected via Oa. The exhaust connection pipe 58 is connected to the air exhaust path 1 formed integrally with the front conduit 14.
4b via a seal 60b. An exhaust pipe 62 formed in a casing 70 described later is connected to the air exhaust path 14b.

The casing 70 and the buried pipe 12
Are formed in a fixed length, and are successively added in accordance with the propulsion length. The exhaust pipe 62 is connected to the joint 52 shown in FIG. A muffler 66 installed on the ground is connected to the joint 52 via an exhaust hose 64. The pressure air exhausted from the air exhaust passage 24d of the hammer case 24 is supplied to the exhaust connection pipe 5
8, air exhaust path 14b, exhaust pipe 62 and exhaust hose 64
Is exhausted from the muffler 66 through

In addition, two lines of the exhaust system are provided in order to realize smooth exhaust (see FIGS. 3 and 6). The supply and discharge of the compressed air are performed as described above, whereby the bit 26 is hit by the piston 28 and vibrates. At the same time, the bit 26 that is struck and vibrated by the piston 28 as described above obtains a rotational force from the propulsion device 16 via the screw pipe 68 as a drive shaft and rotates and protrudes as follows.

As shown in FIG. 5, the screw pipe 68 is disposed so as to penetrate through the buried pipe 12 and the center of the front pipe 14, and the inner pipe 14A of the front pipe 14 and
It is housed in a casing 70 connected to the rear end of the inner tube 14A. And the tip is the bit 26
And is rotatably supported by a bearing 26B formed in a hollow portion 26A.

A projection 68A is formed integrally with the outer periphery of the tip of the screw pipe 68. This projection 6
8A is engaged with a projection 26C formed on the inner periphery of the hollow portion 26A of the bit 26. For this reason, when the screw pipe 68 rotates, the rotation is
The bit 26 is transmitted to the bit 26 via 8A and 26C, thereby rotating the bit 26.

The rear end of the screw pipe 68 is connected to a driving device 72 through the joint 52 shown in FIG. 1. By driving a motor 74 of the driving device 72, the screw pipe 68 rotates. I do. The screw pipe 68 is connected to a water supply hose 76 via a swivel (not shown) of the driving device 72. The water supply hose 76 is connected to a discharge pump 78 installed on the ground. By operating the discharge pump 78, muddy water is supplied into the screw pipe 68 from the tank 80 installed on the ground. You.

When the muddy water is supplied into the screw pipe 68, the supplied muddy water flows out of the tip through the screw pipe 68. Here, as shown in FIG.
The tip of the screw pipe 68 is
The muddy water supplied to the screw pipe 68 once flows out into the bearing portion 26B because the muddy water is fitted into the bearing portion 26B.

The bearing portion 26B is formed with a discharge hole 82 communicating with the tip end surface of the bit 26, and the muddy water flowing into the bearing portion 26B finally passes through the discharge hole 82 to the excavation hole 84. (See FIG. 1). The muddy water supplied to the face face 84A is guided to the hollow portion 26A of the bit 26 from the discharge port 40 formed on the tip end surface of the bit 26 together with the excavated earth and sand excavated by the bit 26. The excavated earth and sand guided to the hollow portion 26A of the bit 26 passes through the inner pipe 14A of the leading conduit 14 and is guided into the casing 70 as shown in FIG.
Discharged through 0.

The screw pipe 68 housed in the casing 70 has a spiral wing (screw) 68B integrally formed on the outer periphery thereof. And
During excavation, the screw pipe 68 is driven by a motor 74 to rotate. Therefore, the excavated earth and sand guided to the hollow portion 26 </ b> A of the bit 26 is transported in the casing 70 by the rotating blade 68 </ b> B of the screw pipe 68, and is thereby discharged from the joint 52.

The propulsion device 16, as shown in FIG.
A base 90 is provided in the starting shaft 86 via leveling jacks 88, 88,.... Base 90
A pair of guide rails 92 are laid on the top, and the propulsion device 16 is slidably supported on the guide rails 92. The propulsion device 16 includes a driving device 72.
Further, a propulsion jack 94 is connected, and by expanding and contracting the propulsion jack 94, a guide rail 92 is provided.
Slide on top.

Here, the casing 70 and the buried pipe 12 connected to the leading conduit 14 are connected to the joint 52, and the joint 52 is propelled by the propulsion jack 94 of the propulsion device 16 so that The thrust is applied to the bit 26. The pneumatic impact type propulsion device 10 of the present embodiment is configured as described above. Reference numeral 96 in FIG. 2 denotes a CCD camera, which is used for measuring the amount of inclination of the air hammer drill 22. The measuring method is as follows.

A target 98 having a grid-like scale is provided in the front conduit 14. A pointer 100 indicating a target 98 is provided in the front conduit 14, and the pointer 100 is connected to a hammer case 24 connected to an air hammer drill 22. The center of the target 98 is irradiated with light from a CCD camera 96. By checking the position of the pointer 100 with the CCD camera 96, the inclination amount of the air hammer drill 22 can be detected.

That is, when the air hammer drill 22 is inclined, the pointer 100 also moves in conjunction with the inclination. Therefore, if the amount of movement of the pointer 100 is measured, the amount of inclination of the air hammer drill 22 can be measured. . At the same time, it can be confirmed whether the leading conduit 14 is propelled along the planning line. The number 10 shown in FIG.
Reference numeral 2 denotes a hydraulic unit that drives the propulsion jack 94 and the like, and reference numeral 104 denotes an operation panel that operates the pneumatic impact type propulsion device 10.

Next, the operation of the embodiment of the pneumatic percussion propulsion device according to the present invention configured as described above will be described. First, as shown in FIG. 1, the bit 26 of the air hammer drill 22 provided at the tip of the leading pipe 14 is brought into contact with the face face 84A. Then, the propulsion jack 94 of the propulsion driving means 16 is extended, and the leading conduit 14 and the buried pipe 12 are propelled.

At the same time, the motor 74 is driven. When the motor 74 is driven, the rotation of the motor 74 is transmitted to the screw pipe 68, and further, the rotation is transmitted to the bit 26 via the screw pipe 68. Thus, the bit 26 rotates. Further, the compressor 56 and the discharge pump 78 are driven at the same time when the motor 74 is driven.

When the compressor 56 is driven, pressurized air is supplied to the air supply pipe 50 shown in FIG. The pressurized air supplied to the air supply pipe 50 is supplied to the hammer case 2 through the air supply path 14 a and the air supply connection pipe 46.
4 is supplied to the first pressure chamber 42 and the second pressure chamber 44 alternately, so that the piston 2
The air hammer drill 22 is operated by vibrating 8.

When the piston 28 vibrates, the bit 26 is hit at the tip end of the piston 28, and the bit 26 is given an impact vibration. And, by this, the face face 84
A is repeatedly hit by the bit 26 and crushed. Exhaust air used to operate the piston 28 of the air hammer drill 22 is exhausted from the joint 52 and the muffler 66 to the atmosphere via the air exhaust passages 28b, 24f, and 24d.

On the other hand, when the discharge pump 78 is driven, the muddy water in the tank 80 is supplied to the screw pipe 68 via the water supply hose 76. The muddy water supplied to the screw pipe 68 flows out from the tip of the screw pipe 68 through the inside of the screw pipe 68, and the bit 2
The water is supplied to the face face 84A from the discharge hole 82 formed on the tip end face of No. 6.

The muddy water supplied to the face 84A is introduced into the hollow portion 26A of the bit 26 through the discharge port 40 together with the excavated earth and sand excavated by the bit 26. The excavated earth and sand and the muddy water guided to the hollow portion 26 </ b> A of the bit 26 are conveyed inside the casing 70 by the blade 68 </ b> B of the rotating screw pipe 68 and discharged through the inside of the casing 70.

As described above, according to the pneumatic impact propulsion device 10 of the present embodiment, the screw pipe 68 is housed in the casing 70, and the screw 26 is rotated to rotate the bit 26, Since the muddy water is supplied to the face face 84A through the inside of the screw pipe 68, the diameter of the leading conduit 14 can be reduced. Therefore, the small-diameter buried pipe 1
2 can be buried.

Further, since the bit 26 is rotated by rotating the screw pipe 68, it can be driven with a small driving force. Further, since the excavated soil is discharged by rotation of the screw pipe 68, smooth discharge can be performed, and the cutting face can be stabilized by controlling the rotation speed and adjusting the discharge amount. Also,
The stability of the face makes it easier to control the accuracy.

In the present embodiment, the screw pipe 68 is used as the drive shaft. However, the present invention is not limited to this, and the excavated earth and sand may be transported by a pipe without a screw. In the present embodiment, the pressure air supply / exhaust line that operates the piston 28 is completely disconnected from the muddy water supply line, and the exhaust gas is not exhausted into the drilling hole 84. The power can be controlled freely. This does not adversely affect the face face 84A and does not cause a drop in the impact force.

Further, since the impact excavation method using the air hammer drill 22 is employed, it is possible to effectively propel even hard ground such as a rock layer, a boulder, and a boulder. Further, since the direction is corrected directly by the air hammer drill 22, the direction can be easily corrected. In addition, the air hammer drill 22
Bit 26 has seals 26, 3 on its inner and outer diameters.
4, the air hammer drill 22 is provided.
Muddy water does not enter inside. For this reason, it can be effectively used even in a stratum containing water. Also, by providing the bit 26 with the seals 26 and 34 interposed therebetween, it is possible to effectively prevent air from leaking into the hole.

[0040]

As described above, according to the present invention,
The hard ground can be efficiently drilled by the impact force of the air hammer drill, and the ground can be stabilized because the exhaust air is exhausted to the ground by another circuit without being discharged into the hole. In addition, since the bit of the air hammer drill is rotated by rotating the screw pipe and muddy water is supplied to the drilling part by passing through the inside of the screw pipe, it is possible to reduce the diameter of the leading pipe. it can. In addition, since the excavated earth and sand is discharged by rotation of the screw pipe, smooth discharge can be performed.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an embodiment of a pneumatic impact propulsion device according to the present invention.

FIG. 2 is a side sectional view showing a configuration of a leading conduit.

FIG. 3 is a sectional view taken along line AA of the leading conduit shown in FIG. 2;

FIG. 4 is an enlarged view of a main part of the leading conduit shown in FIG. 2;

FIG. 5 is a side sectional view showing a configuration of a front conduit.

FIG. 6 is a sectional view taken along line AA of the leading conduit shown in FIG. 5;

FIG. 7 is an enlarged view of a main part of the leading pipe shown in FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Pneumatic impact type propulsion device 12 ... Buried pipe 14 ... Lead pipe 22 ... Air hammer drill 26 ... Bit 50 ... Air supply pipe 62 ... Exhaust pipe 68 ... Screw pipe (drive shaft) 70 ... Casing 74 ... Motor 94 ... Propulsion jack

Claims (2)

[Claims] 1. A propulsion method, comprising: a casing fixed to a leading pipe leading a buried pipe, and having a casing penetrating the leading pipe and a central part of the buried pipe, wherein a thrust is applied to the casing and the buried pipe to bury the pipe. An air hammer drill having a rotatable bit at the tip, a center formed hollow, and having an air supply and exhaust passage, and which is disposed in the casing; And a drive shaft that penetrates the center of the air hammer drill and transmits a rotational force to the bit; an air supply line that is disposed on the casing and that operates a piston of the air hammer drill; A pneumatic impact type propulsion device, comprising: an exhaust line for air provided for operating a piston of the air hammer drill. 2. The drive shaft is a screw pipe having a screw disposed therein, and water is supplied from a discharge port of the bit to a digging portion through the inside of the screw pipe, and excavated soil is taken in from a discharge port of the bit. 2. The pneumatic percussion propulsion device according to claim 1, wherein earth is discharged through the inside of said casing by rotation of said screw pipe.