JPS6143513B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a drilling device used for digging deep wells for extracting oil, groundwater, etc., or for civil engineering work, etc., and particularly relates to a drilling device that is used for drilling deep wells for extracting oil, groundwater, etc., or for civil engineering work, etc. Pressurized water is used to send the bit holder with the bit attached to the underground end of the drill pipe, the bit holder is locked to the underground end of the drill pipe using a locking device, and the drill pipe is rotated to hold the bit. The present invention relates to a drilling device capable of drilling a hole in the ground with an inner diameter larger than the outer diameter of a drill pipe using a bit and a hole expanding cutter provided in a bit holder by pushing the drill pipe into the ground while rotating the drill pipe.

In this type of drilling equipment, the hole expanding cutter is provided to widen the hole drilled with a bit from the outside diameter of the drill pipe so that the drill pipe can enter the hole as the hole is being excavated. Based on the concept of expanding the hole drilled with a hole-expanding cutter, in conventional drilling equipment, the hole-expanding cutter was installed on the ground side of the bit that drills the center of the hole.

The circumferential speed is higher in the part far from the center of rotation than in the part near the center of rotation. Therefore, the outer periphery of the hole is cut into a cylindrical shape using a hole expanding cutter that cuts the outer periphery of the hole first than the bit that cuts the center of the hole. We focused on the fact that drilling could be done more efficiently than before by cutting the center of the column-shaped hole with a bit, and in order to do this, we placed the hole-expanding cutter deeper underground than the bit and attached it to the bit holding part. It is equipped with a bit and a hole expanding cutter.

The hole expanding cutter attached to the bit holder must be able to be stored inside the inner diameter of the drill pipe so that the bit holder can move freely within the drill pipe. Since the conventional hole-expanding cutter was provided on the ground side of the bit, it is necessary to provide a storage section for the hole-expanding cutter in the bit holding section. For this reason, the part of the bit that touches the shank is used as a storage area for the hole-expanding cutter, so the cross-sectional area of the part of the bit that touches the shank becomes smaller, and in order to maintain the necessary strength, the size of the bit is limited. Ru. For this reason as well, the cutting efficiency of the hole-expanding cutter could not be increased. In contrast, in the present invention, the hole-expanding cutter is placed closer to the ground than the bit, which allows for sufficient storage space for the hole-expanding cutter, and the cutting efficiency is improved by using a larger hole-expanding cutter than before. I can do it,
The cross-section of the shank portion of the bit is also large to the extent that a housing section for the hole-expanding cutter is not required, and it is possible to provide a drilling device that also has the advantage of being sufficiently strong.

An embodiment of the present invention shown in the figures will be described.

The upper half of FIG. 1 shows when the bit holder is locked with respect to the drill pipe, and the lower half shows when it is unlocked.

1 is a drill pipe, 2 is an outer pipe, and 3 is an inner pipe, the outer pipe 2 has an outer diameter that can be inserted into the drill pipe 1, and the inner pipe 3 has an outer pipe that can be moved in the axial direction into the outer pipe 2. 2
inserted inside. Bit 4 is attached to the lower end of inner tube 3.
and a hole expanding cutter 5 are attached, and the inner tube 3 structurally serves as a bit holding section. The bit 4 is attached to the center of the lower end of the inner tube 3. The hole expanding cutter 5 is attached to the inner tube 3 via a handle 6, and is positioned so as to protrude underground from the bit 4. The handle 6 has a hole expanding cutter 5 fixed to one end.
The other end is fitted into grooves 7 formed on the outer periphery of the lower end of the inner tube 3 at intervals of 120 degrees, for example, and is attached to the inner tube 3 with pins 8 perpendicular to the diameter direction of the inner tube 3 within the grooves 7. It is designed to be able to rotate in a plane parallel to the diametrical direction of the inner tube 3 using the inner tube 3 as a fulcrum. A spring 9 is inserted between the bottom of the groove 7 and the handle 6 from the other end of the pin 8 of the handle 6, and this spring 9 causes the hole expanding cutter 5 to protrude from the lower end of the drill pipe 1. This allows a part of the hole expanding cutter 5 to be moved beyond the outer diameter of the drill pipe 1. By moving the outer tube 2 relative to the inner tube 3, the other end of the handle 6 is pressed and released from the outside with the lower end 2a of the outer tube 2, and the hole expanding cutter 5 is moved into the drill pipe 1. It can be maintained inside the inner diameter or projected outside the outer diameter of the drill pipe 1.

A lock piece 10 is provided in a recess formed on the surface slightly above the lower end of the inner tube 3 so as to fit within the outer periphery of the inner tube 3, and a portion of the lock piece 10 along the circumferential direction of the inner tube 3 is provided. is provided so as to be able to protrude to the outside of the inner tube 3 by means of a spring (not shown). A locking piece operation window 11 is opened in a part of the outer tube 2 where the locking piece 10 is located. The locking piece operating window 11 is located at a position where the hole expanding cutter 5 protrudes ahead of the lower end of the drill pipe 1, a portion protrudes outside the outer diameter of the drill pipe 1, and is held by the lower end of the outer pipe 2. A part of the locking piece 10 can be projected outside through a locking piece operating window 11. On the inner surface of drill pipe 1,
The lock piece 10 just protrudes from the lock piece operation window 11.
A recess 12 is formed which engages a part of the drill pipe 1 with the locking piece 10 relatively immovably in the axial and circumferential directions of the drill pipe 1. The tube 3 is fixed to the drill pipe 1 so that it can rotate together with the drill pipe 1 and can also move together in the axial direction. When the outer tube 2 is moved upward (toward the ground side) so that the lower end 2a of the outer tube 2 is separated from one end of the handle 6 and positioned inside the drill pipe 1 by the hole-expanding cutter 5,
A portion of the locking piece 10 is gradually held down inside the outer tube 2 by the edge of the locking piece operating window 11 of the outer tube 2, and is pushed into the outer tube 2 by the inner surface of the outer tube 2 as shown in the lower half of FIG. , is adapted to be maintained within the outer tube 2.

The upper end of the inner pipe 3 on the ground side is slightly shorter inward than the upper end of the outer pipe 2, and as described above, the upper end of the outer pipe 2
When the inner tube 3 and the inner tube 3 are moved relative to each other in the axial direction, a fan-shaped water stopper at an angle of approximately 140° is formed at the upper part 2b of the outer tube 2, which overlaps or does not overlap with the upper end of the inner tube 3. A piece 13 protrudes from and faces the outer circumference of the outer tube 2, and is attached to the outer tube 2 by spline fitting so as not to be movable in the circumferential direction. The outer tube 2 is provided with a water passage hole 14 that communicates between the inside and the outside, and extends downward from between the water stop pieces 13 to a portion where the outer tube 2 and the inner tube 3 always overlap.

A locking piece 15 is attached via a wedge to a portion of the inner tube 3 facing the water passage hole 14 of the outer tube 2 so as not to be movable in the circumferential direction of the outer tube 2. The locking piece 15 is formed to protrude outward from the water passage hole 14 of the outer tube 2 and to form a closed ring with the water stopper piece 13.

The spline connecting the outer tube 2 and the water stopper piece 13 is such that the spline provided on the outer surface of the outer tube 2 connects the water stopper piece 13.
The water stop piece 13 is slightly longer than the axial width of the water stop piece 13.
can be moved slightly in the axial direction with respect to the outer tube 2, and the locking piece 15 can also be moved slightly in the axial direction with respect to the inner tube 3 along the wedge.

The aforementioned locking piece 10 is inserted into the recess 12 of the drill pipe 1.
When the outer tube 2 is moved to a position where the hole expanding cutter 5 can be held in a protruding state beyond the outer diameter of the drill pipe 1, the water stopper piece 13 and the locking piece 15 are on the same circumference. The end surface of this toroidal body on the underground side comes into contact with an annular step 16 formed on the inner surface of the drill pipe 1 and facing toward the ground side. The water piece 13 and the locking piece 15 cooperate with the annular step 16 to close the space between the outer pipe 2 and the drill pipe 1, so that the water sent from the ground side inside the drill pipe 1 is 2 and the drill pipe 1 to prevent it from flowing toward the lower end. The locking piece 15 and the annular step 16 lock when the outer pipe 2 and the inner pipe 3 have been moved from the ground side to the underground side and the locking piece 10 is not yet engaged with the recess 12. The piece 10 serves as a locking device for stopping the inner tube 3 in a position opposite the recess 12.

There is a water intake port 17 provided at the upper end of the outer pipe 2 so as to communicate with the inner pipe 3, and water entering from the water intake port 17 passes through the inner pipe 3 and from the lower end of the inner pipe 3.
It is designed to be supplied near the bit 4 and the hole-expanding cutter 5.

The upper end of the outer tube 2 is also provided with a conical riveted protrusion 18 that protrudes toward the ground side.

The bit holding part consisting of the outer tube 2, inner tube 3, etc. moves the outer tube 2 to the upper end side with respect to the inner tube 3 so that the hole expanding cutter 5 can be inserted into the drill pipe 1, and also locks the bit. The stopper 10 is attached to the outer tube 2 by the outer tube 2.
Insert the drill pipe 1 into the drill pipe 1 from the ground side end of the drill pipe 1, and supply pressurized water into the drill pipe 1 from above, and pressurize the water to the underground side end of the drill pipe 1. sent towards. The inner pipe 3 that has reached the underground side is stopped at the locked position by the locking piece 15 hitting the annular step 16. Next, due to inertia and water pressure, the outer pipe 2 moves underground, expanding the hole expanding cutter 5 that protrudes from the lower end of the drill pipe 1, and the locking piece 10
is engaged with the recess 12 to connect the drill pipe 1 and the inner pipe 3 together. At the same time, the water stopper piece 13 provided on the outer pipe 2 comes into contact with the annular step 16 to form a ring with the locking piece 15, and water passes between the outer pipe 2 and the drill pipe 1 and the water enters the drill pipe 1. Since water is prevented from flowing to the lower end, water is supplied from the water intake port 17 through the inner pipe 3 to the vicinity of the bit 4 and the hole-expanding cutter 5. In this state, if the drill pipe 1 is rotated from the ground and pushed toward the ground at the same time, a hole can be drilled into the ground.

If the penetration speed of the drill pipe 1 into the ground decreases due to wear of the cutting blades of the bit 4 or the hole-expanding cutter 5, and it becomes necessary to replace the bit 4 or the hole-expanding cutter 5, remove the hook at one end. Insert the wire attached to the drill pipe 1 into the drill pipe 1, send the hook underground with water flow, engage the hook with the protrusion 18 at the upper end of the outer pipe 2, and then insert the wire attached to the inner pipe 3, the outer pipe 2, etc. can be pulled out to the ground. At this time, the outer tube 2 is first moved to the ground side relative to the inner tube 3 by the wire as shown in the lower half of FIG. Due to this movement of the outer tube 2, the hole expanding cutter 5 falls within the inner diameter range of the outer tube 2, and the locking piece 10 is pushed into the outer tube 2 by the locking piece operation window 11 and is connected to the inner tube 3. The engagement with the drill pipe 1 is released. At the same time, the water stop piece 13 is
As shown in the lower half of the figure and in FIG. 2, the locking piece 15 moves to the ground side and becomes different in level, allowing water to pass underground through between the outer pipe 2 and the drill pipe 1. In this state, the inner pipe 3, outer pipe 2, etc. can be pulled up toward the ground using wires, so that the water in the drill pipe 1 is drained into the inner pipe 3 and between the outer pipe 2 and the drill pipe 1. Since the load of water on pulling is reduced, the lifting work can be easily carried out.

The water stopper piece 13 and the locking piece 15 can be moved in the axial direction if they are formed so that the locking piece 10 is securely pressed against the annular step 16 of the drill pipe 1 at the position where the locking piece 10 engages with the recess 12 of the drill pipe 1. Outer tube 2 and inner tube 3 so that
may be fixed respectively. However, due to wear due to use, etc., the lock piece 10 of the outer tube 2 is closed to the lock piece operating window 1.
When the locking piece 10 becomes difficult to pull into the outer pipe 2 due to the edge of the drill pipe 1 biting in, in order to make it easier to unlock by shaking the drill pipe 1 up and down, or to allow for dimensional errors, the above-mentioned method can be used. As shown in the embodiment, it is more convenient to use the water stopper piece 13 and the locking piece 15 so that they can be moved slightly in the axial direction.

Further, the water passage hole 14 may be extended above the water cutoff piece 13 to communicate with the inside of the inner pipe 3, and this portion may be used as the water intake port 17.

According to the device of the present invention, by providing the hole-expanding cutter 5 on the underground side of the bit 4, the hole-expanding cutter 5 becomes a shank of the bit 4 as in the case where the hole-expanding cutter 5 is provided on the ground side of the bit 4. There is no need to provide a storage part for the hole-expanding cutter 5 in the inner tube 3, the holding part for the bit 4 can be made thick and strong, and the hole-expanding cutter 5 can be made large because it can be stored in an empty space inside. The hole-expanding cutter 5 is now larger than the conventional one, and the enlarged hole-expanding cutter 5 cuts the cylindrical hole 19 at a peripheral speed higher than the bit 4 as shown in FIG. Since the drill hole is drilled by cutting and crushing the drill bit using Bit 4, it is possible to provide a drilling device with better drilling performance than the conventional drill.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a drilling device according to the present invention, in which the upper half shows the state in which the inner pipe 3 is locked to the drill pipe 1, and the lower half shows the state in which the inner pipe 3 is unlocked from the drill pipe 1. 2 is a perspective view showing the relative positions of the outer tube 2 in FIG. 1, the water stopper piece 13, the locking piece 15, and the water passage hole 14, and FIG. and the sectional view taken along line A-A in FIG. 2, and FIG. 4 show the water stop piece 13
3 is a perspective view showing the relationship between the locking piece 15 and the locking piece 15. FIG. 1...Drill pipe, 2...Outer pipe, 2a...Lower end, 2b...Upper part, 3...Inner pipe, 4...Bit,
5... Hole expansion cutter, 6... Handle, 7... Groove, 8...
...Pin, 9...Spring, 10...Lock valve, 11...
Lock stopper operation window, 12... recess, 13... water stopper,
14... Water hole, 15... Locking piece, 16... Annular step, 17... Water intake port, 18... Projection, 19
... Cylindrical hole, 20 ... Central core.

Claims (1)

[Claims] 1 Comprising a drill pipe, an outer pipe that can be inserted into the drill pipe, and an inner pipe that is movably inserted in the outer pipe in the axial direction, and the inner pipe is attached to the inner pipe at the lower end of the drill pipe. A portion of the locking piece protrudes from the locking piece operating window provided on the outer pipe and engages with a recess provided on the inner surface of the drill pipe, making it immovable relative to the drill pipe and capable of rotating together with the drill pipe, At the same time, in a drilling device in which a bit and a hole-expanding cutter provided at the lower end of the inner tube protrude beyond the lower end of the drill pipe, and one end of the hole-expanding cutter is held in a state of protruding outside the circumferential surface of the drill pipe, A drilling device characterized in that the hole-expanding cutter is located underground from the bit.