JPH0259273B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method and apparatus for drilling a pile hole or the like into the ground using an air hammer drill.

[Prior Art] An example of an air hammer drill is shown in Fig. 1. The air hammer drill has a compressed air supply pipe 1 communicating with a compressor, and two upper and lower chambers 2 and 3 into which air is fed from the supply pipe 1 through appropriate valves. , a piston 4 that moves between the chambers 2 and 3, and a hammer 5 located below the piston 4. Compressed air is fed into the chambers 2 and 3 to move the piston 4 up and down, and the piston 4 drives the hammer 5 by impact. The scrap excavated by the chip 6 at the tip of the hammer 5 is carried upward from the outside by the air discharged from the lower chamber 3 to the end of the hammer 5.

[Problem to be solved by the invention]

In this way, an air hammer drill uses air to carry the excavated waste upward through the annular gap formed between the hole wall and the outer circumferential surface of the hammer, but if this gap is wide, the air coming out of the hammer will be dispersed. The problem was that the force was weakened and it was not possible to raise the slop properly.

The purpose of the present invention is to eliminate the disadvantages of the conventional example,
To provide an underground drilling method and device capable of reliably transporting excavated waste upwards without using an air hammer drill with a large drill (anvil) diameter when drilling a large diameter hole.

[Means for Solving the Problems] In order to achieve the above object, the present invention drills a hole in the ground using a hammer drill that is placed in the hole and driven by compressed air supplied from above through a pipe. In this method, an air hammer drill is connected to the tip of the screw shaft, and a hole with an outer diameter equal to or larger than the hammer diameter of the air hammer drill and from the lower end to the upper end on the outer circumferential surface is used. A drilling device is used in which a mantle tube formed with a continuous turning upward groove is arranged so that the lower surface of the hammer protrudes outside the air hammer drill, and the air for conveying the excavated waste is supplied to the mantle tube outside the hammer. The gist of this is to rotate and rise above the surface.

[Effect]

According to the present invention, since the mantle tube is provided on the outside of the air hammer drill, the mantle tube is located between the hole wall or the casing, and the only space left is the turning upward groove on the outer peripheral surface of the mantle tube.

Therefore, the air for transporting the excavated waste passes only through the turning upward groove, and can efficiently carry the excavated waste upward without being dispersed.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

Fig. 2 is a partially cutaway front view showing an embodiment of the device of the present invention, and this embodiment is used in combination with an air hammer drill and a drilling casing disposed outside the drill to create a large diameter hole. It is.

In the figure, reference numeral 10 denotes a rotary shaft having a conveyance screw 11 provided on the outside thereof, and an air hammer drill 12 as described in FIG. 1 is connected to the tip thereof.

Incidentally, this shaft 10 is connected to a rotor (not shown) at the upper side, and the hollow portion inside constitutes a pipe that communicates the compressor with the air hammer drill 12.

On the outside of the air hammer drill 12, there is a drill 1
The mantle tube 13 is attached so that the lower surface of the hammer 5 of No. 2 protrudes a little, and the outer peripheral surface of the mantle tube 13 has a groove 14 that rises while turning from the lower end to the upper end.
form.

In the figure, reference numeral 15 denotes an excavation casing disposed further outside this mantle cylinder 13, and a spiral blade 1 is provided on the outer peripheral surface.
6, and a cutting claw 17 having a horizontal cutting edge at the tip was implanted on the lower end surface.

For example, if the diameter of the hammer 5 of the drill 12 is approximately φ300 and the diameter of the casing 15 is approximately φ650, the diameter of the outer mantle 13 is increased by enlarging the diameter of the hammer 5 and the gap with the casing 15. It should be approximately φ450 located at .

Next, the method of the present invention using the above-mentioned apparatus will be explained.

The air hammer drill 12 with the mantle cylinder 13 attached thereto and the casing 15 are inserted into the hole, and each is separately driven to rotate.

Compressed air is fed into the air hammer drill 12 from a compressor (not shown) via a shaft 10, and the hammer 5 is driven to vibrate.

The scraps of the rock etc. cut by the tip 6 at the tip of the hammer 5 are removed from the mantle tube 13 along with the air coming out of the hammer 5.
It turns and rises using the groove 14 as a guide, and eventually reaches the lower end of the screw 11 of the shaft 10, and is thereafter carried upward by this screw 11. In this case, the annular gap in the casing 15 is narrow because of the outer sleeve 13, and since it is along the groove 14, the air discharged from the hammer 5 does not diffuse and rises forcefully at a fast speed. The waste can be surely carried up to the screw 11.

In addition, in the above embodiment, the excavation casing 15 is provided on the outside.
Although a case has been described in which excavation is performed even with this casing 15, the present invention works effectively even when such a casing is not provided.

〔Effect of the invention〕

As described above, the underground drilling method and apparatus of the present invention are for drilling underground using a hammer drill that is placed in a hole and driven by compressed air supplied from above through a pipe. In the drilling method, in which a hole is drilled and the excavated waste is transported upward by the air emitted from the hammer, there is no need to form a wide annular space outside the hammer, and as a result, the air emitted from the hammer is not dispersed, allowing for efficient drilling. It is able to carry waste upwards.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing an example of an air hammer drill, and FIG. 2 is a partially cutaway front view showing an embodiment of the apparatus of the present invention. 1... Compressed air supply pipe, 2, 3... Chamber, 4... Piston, 5... Hammer, 6... Chip, 10... Rotating shaft, 11... Screw, 12
... Air hammer drill, 13 ... Mantle tube, 14
...Groove, 15...Drilling casing, 16...Spiral blade, 17...Cutting claw.

Claims (1)

[Claims] 1. A hammer drill placed in the hole and driven by compressed air supplied from above through a pipe is used to drill a hole in the ground, and the excavated waste is removed by the air emitted from the hammer. In the upward conveyance drilling method, an air hammer drill is connected to the tip of the screw shaft, and a mantle tube with an outer diameter larger than the hammer diameter of the air hammer drill and with a continuous upward turning groove formed on the outer circumferential surface from the lower end to the upper end is used. The air hammer drill is characterized in that a drilling device is disposed on the outside of the hammer so that the lower surface of the hammer protrudes, and the air for conveying the excavated waste is raised by rotating on the outer cylindrical surface of the outside of the hammer. Inner drilling method. 2. An air hammer drill is connected to the tip of the screw shaft, and an outer sleeve having an outer diameter equal to or larger than the hammer diameter of the air hammer drill and having a continuous upward turning groove formed on the outer circumferential surface from the lower end to the upper end is attached to the outside of the air hammer drill. A device for drilling into the ground, characterized in that the lower surface of the hammer is arranged so as to protrude.