JP3233181B2 - Drilling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a drilling device used for installing an earth anchor.

[0002]

2. Description of the Related Art Conventionally, an earth anchor method has been widely used for the purpose of preventing falling of a retaining wall or a pier, prevention of buoyancy of a dock floor plate and prevention of ground slippage.

In this earth anchor method, the ground is drilled with a drill bit at the tip of the casing pipe while pouring water is injected into a casing pipe connected to the drilling machine, and an anchor cable is inserted into the drilled anchor hole. (Steel wire)
Grout material is injected into the anchor hole under pressure while pulling out the casing tube to create an anchor body in the ground to connect the ground and the structure. They are sequentially connected in response.

[0004] Conventionally, when an earth anchor is constructed on soft ground, a so-called disposable bit such as a kronen bit has been used as a drill bit. As shown in FIG. 14, the kronen bit 1 is mounted on the casing tube 3 via a drive shoe 5 screwed to an insertion-side end of the casing tube 3, and the cylindrical portion 1 inserted into the drive shoe 5.
a and a head 1 b disposed at the tip of the drive shoe 5. Then, while inserting the cylindrical portion 1a into the drive shoe 5, the notch 7 provided at the rear end of the head 1b is engaged with the notch 9 at the tip of the drive shoe 5 in the axial direction (hole drilling direction). By being connected to the drive shoe 5, the rotation of the casing tube 3 is transmitted to the kronen bit 1.

When the casing tube 3 is pulled out while pouring the grout material, the kronen bit 1 is separated from the drive shoe 5 and remains in the anchor hole, and is buried by the grout material. I have. In the figure,
Numeral 11 denotes a hole for drilling water.

[0006]

As described above, conventionally, the kronen bit 1 is engaged with the drive shoe 5 in the axial direction when the earth anchor is installed, and the krone bit 1 is pulled out of the casing tube 3. It is structured to be separated from the drive shoe 3.

[0007] By the way, when drilling the ground, for example, in the case where the casing pipe 3 comes into contact with hard rock or in the formation where the casing pipe 3 is tightened with the drilling like a gravel layer, the casing pipe 3 is flushed. It is necessary to apply a striking force to the drill bit and excavate the ground while removing the slime on the outer periphery of the casing pipe by moving the casing pipe up and down.

[0008] However, in the conventional connection structure between the Kronen bit 1 and the drive shoe 5 as described above, the Kronen bit 1 is detached from the drive shoe 5 by flushing the casing tube 3.
In addition, the detached Kronenbit 1 is replaced with a drive shoe 5
It is difficult to connect to the drive shoe, and a connection structure between a kronen bit and a drive shoe capable of performing a flushing operation has been desired.

The present invention has been devised in view of the above circumstances, and enables a flushing operation of a casing tube at the time of drilling an anchor hole, and a detachment of a drill bit and a drive shoe at the time of pulling out a casing tube. An object of the present invention is to provide a drilling device for earth anchor installation that can be easily performed.

[0010]

In order to achieve the above object, a drilling device according to claim 1 is screwed to a tip end of a casing pipe connected to a drilling machine, and has a pin engaging groove on an inner periphery thereof. Is formed, and the driving shoe is meshed with the driving shoe in the axial direction and connected to the tip thereof, and a water ejection hole for drilling is formed in a head arranged at the tip of the driving shoe, and is inserted into the driving shoe. Drilling bit with a plurality of pin insertion holes formed in the peripheral wall of the cylindrical portion, and is disposed in the drilling bit, and inserted into the pin insertion hole of the drilling bit to engage with the pin engagement groove of the drive shoe. A bit connecting jig having a mounting pin mounted thereon, and a bit connecting jig recovering jig which is inserted into the casing tube so as to be able to move up and down and recovers the bit connecting jig. Bit connection by jig In raising the tool, characterized by retreat from the pin insertion hole of the drilling bit.

The invention according to claim 2 is based on claim 1
In the drilling device according to the above, the bit connecting jig arranged in the drilling bit includes a locking portion provided with locking claws and a locking portion slidable upward, and biasing the mounting pin outward to the bit connection jig. A bit connecting jig recovering jig, which includes a spring for engaging and holding the mounting pin in the pin engaging groove of the drive shoe, and a wire connecting the mounting pin and the locking portion, and which is inserted into the casing pipe so as to be able to move up and down. The locking claw is provided with a locking claw that can be elastically locked, and the mounting pin pulls up the wire by pulling up the locking portion by the bit connecting jig recovery jig locked via the locking claw. And retreats from the pin insertion hole of the drill bit through the hole.

[0012]

According to the drilling device of the first aspect, if the mounting pin of the bit connecting jig is engaged with the pin engaging groove of the drive shoe through the pin insertion hole of the drill bit, the drive shoe and the driving shoe can be connected. The drill bit will be connected.

[0013] Therefore, if the drive shoe to which the drill bit is connected is screwed to the tip of the casing tube and the ground is drilled while drilling water is supplied into the casing tube, an anchor hole is formed in the ground. Will be drilled. Even when the casing tube is flushed during drilling, the drilling bit does not come off the drive shoe because the mounting pin is engaged with the pin engaging groove via the pin insertion hole.

After the drilling is completed, the bit connecting jig collecting jig is inserted into the casing tube, and the bit connecting jig is pulled up by the bit connecting jig collecting jig. Then, the connection state between the drive shoe and the drill bit is released.

After that, if the anchor pipe is inserted into the anchor hole and the casing tube is pulled out while the grout material is injected under pressure, the drill bit is separated from the drive shoe and left in the anchor hole. It will be buried in the anchor hole by the grout material.

Further, according to the drill bit of the second aspect,
After engaging the locking claw of the bit connecting jig collection jig inserted into the casing tube with the locking claw of the locking portion of the bit connecting jig, pull up the locking portion with the bit connecting jig collecting jig. If
The wire retracts the mounting pin from the pin insertion hole against the spring force of the spring to release the connection between the drive shoe and the drill bit.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an embodiment of a drilling device according to claim 1 and claim 2. In the drawing, reference numeral 13 denotes a drive shoe screwed to the tip of a casing tube, as in the conventional case, and an inner periphery of the drive shoe. The pin engagement groove 15 is formed. A drill bit 17 is axially meshed and connected to the tip of the drill bit.

The drill bit 17 includes a head 17a disposed at the tip of the drive shoe 13 and a cylindrical portion 17b inserted into the drive shoe 13.
a is provided with a plurality of holes 19 for drilling water.
As shown in FIG. 7, pin insertion holes 21 are provided on the peripheral wall of the cylindrical portion 17b at intervals of 120 ° in correspondence with the pin engagement grooves 15. In the cylindrical portion 17b, a check valve 23 similar to the conventional one is mounted on the back side of the head 17a.

That is, in FIG. 1, reference numeral 25 denotes a valve seat provided at the center with a water supply passage 27 which expands downward in a tapered shape. The valve seat 25 is fixed to the inner periphery of the cylindrical portion 17b. I have. Then, the ball valve 31 urged by the spring 29 stretched between the back surface of the head 17a and the valve seat 25 contacts the valve seat 25 to close the water supply passage 27, and the drilling water W is injected into the casing pipe. Then, as shown by a two-dot chain line, the ball pressure 31 moves downward against the spring force of the spring 29 by the water pressure, and the water supply passage 27 is opened. In the drawing, reference numeral 33 denotes an O-ring that seals a gap between the drive shoe 13 and the drill bit 17.

A bit connecting jig 35 having the same central axis as the drive shoe 13 is provided above the check valve 23.
Is arranged. The bit connecting jig 35 includes a cylindrical jig main body 35 a having a bottom, a locking portion 35 b which is inserted into an upper portion of the jig main body 35 a and is slidable upward, and a jig main body 3.
And a cylindrical leg 35c fixed to the lower portion of the casing 5a. A water passage hole 37 through which drilling water W sent into the casing pipe passes is formed on the peripheral wall of the leg 35c at 90 ° intervals. Open is provided.

A locking claw 39 is provided on the outer periphery of the locking portion 35b at an interval of 180 ° to project diagonally downward.
A bit connecting jig recovery jig 41 described later is attached to the locking claw 39.
The locking claws 43 are elastically locked. As shown in FIG. 1, the locking portion 35b is usually mounted on a step 45 provided in the jig body 35a, and the locking claw 43 is attached to the locking claw 39 as shown in FIG. When the bit connecting jig recovery jig 41 is pulled upward by locking, the locking portion 35b is pulled upward in conjunction with this, and when the locking portion 35b is pulled up by a certain amount, the locking portion 35b is raised. An annular stopper member 47 attached to the outer periphery of the rear end of the jig abuts on the peripheral edge of the opening of the jig main body 35a to restrict the movement of the locking portion 35b. The jig body 35a is adapted to be engaged with the jig main body 35a via 35b.

Reference numeral 49 denotes a jig main body 3 with an interval of 120 °.
A mounting pin 53 is attached to a peripheral wall of the mounting pin 5a. A mounting pin 53 urged outward by a spring 51 is mounted in each mounting pin housing 49. Each of the mounting pins 53 urged by the spring 51 is inserted into the pin insertion hole 21 and engaged with the pin engagement groove 15, and the mounting pin 53 is thus pinned through the pin insertion hole 21. Engagement groove 1
By engaging with 5, the drill bit 17 is connected to the drive shoe 13.

The locking portion 35b and each mounting pin 5
3 are connected by wires 55 arranged in the jig body 35a and the locking portion 35b, respectively, and as the bit connecting jig recovery jig 41 raises the locking portion 35b upward as described above, the spring Wire 5 against the spring force of 51
5 retreats the mounting pin 53 into the mounting pin housing 49 to release the engagement with the pin engaging groove 15. And, as shown in FIG.
7 is in contact with the peripheral edge of the opening of the jig body 35a, the mounting pin 53 is completely disengaged from the pin insertion hole 21 and retreats into the mounting pin housing 49, and in this state, the bit connecting jig is further recovered. When the jig 41 is pulled up, the entire bit connecting jig 35 is pulled up as shown in FIG. The ends of the wires 55 are respectively connected to the locking portions 35 b and the mounting pins 53 by an epoxy adhesive 57.
Are fixed to the mounting recesses 59 and 61.

In FIG. 1, 63 is the mounting pin housing 4
9, a stopper device for the locking portion 35b mounted above the
The stopper device 63 includes a stopper 67 which is constantly urged into the jig main body 35a by a spring 65, and the stopper member 47 against the spring force of the spring 65 causes the stopper 67 to move as the locking portion 35b rises. After pressing and passing through the stopper member 47, the stopper 67 is
Projecting into the jig body 35a again with the restoring force of
5b is prevented from falling down. In addition, in FIG. 1, reference numeral 69 denotes an O-ring for sealing between the jig main body 35a and the locking portion 35b.

FIG. 5 is a partially cutaway side view of a bit connecting jig recovery jig 41 inserted into a casing tube so as to be able to move up and down. In FIG. Four connected guide plates 75 are attached to the outer periphery of the connected cylindrical support portion at 90 ° intervals. These guide plates 75 arrange the bit connecting jig collecting jig 41 at the center of the casing tube when inserting the bit connecting jig collecting jig 41 into the casing tube. The dimension m between the tops 75a is set to a dimension slightly shorter than the inner diameter of the casing tube. A fixed arm member 77 is fixed to a lower portion of the support portion 71.

As shown in FIG. 6, the upper portion of the fixed arm member 77 is formed to have a U-shaped cross section, and a claw member 79 is attached to an arm portion 77a extending below the fixed arm member 77. An inwardly bent locking claw 43 is formed at the tip of.

In the drawing, reference numeral 81 denotes a movable arm member,
The upper part of the movable arm member 81 having a U-shaped cross section is fitted into the fixed arm member 77, and is mounted on the fixed arm member 81 via the mounting shaft 83 as shown in FIG. The claw member 79 is also attached to the arm portion 81a extending opposite to the portion 77a. A spring 85 is stretched between the rear portions 77b and 81b of the two arm members 77 and 81 formed in a U-shaped cross section.
Is urged in the direction of arrow A about the mounting shaft 83, and the two arm portions 77a and 81a are maintained in a parallel state.

When the bit connecting jig 35 is recovered, the locking claw 43 of the bit connecting jig recovering jig 41 inserted into the casing tube comes into contact with the outer periphery of the locking claw 39 of the bit connecting jig 35. As shown by the two-dot chain line, the spring 8
5, the movable arm member 81 moves in the direction of arrow B about the mounting shaft 83 as the center of rotation, and the locking claw 43 is locked by the locking claw 39. With a restoring force of 85, it returns elastically to the state shown by the solid line. FIG. 7 is a bottom view of the locking claw 43.

1, 87 is a notch formed at the rear end of the head 17a of the drill bit 17, and 89 is formed at the tip of the drive shoe 13 as in the conventional example shown in FIG. The rotation of the casing tube is transmitted to the drill bit 17 by engaging the two notches 87 and 89 in the axial direction (the drilling direction).

Since the drilling device according to the present embodiment is configured as described above, to construct an earth anchor using the drilling device, first, as shown in FIG.
7 and cutout 89 of drive shoe 13
Are axially engaged with each other, and the mounting pin 53 of the bit connecting jig 35 is engaged with the pin engaging groove 15 of the drive shoe 13 through the pin insertion hole 21 of the drill bit 17.
Thus, the drive shoe 13 and the drill bit 17 are connected.

Then, as shown in FIG. 8, the drive shoe 13 is screwed to the tip of the casing tube 91 connected to the drilling machine, and while drilling water W is supplied into the casing tube 91,
As in the conventional case, the casing pipes 91 may be sequentially connected in accordance with the drilling depth to drill the anchor holes 95 in the ground 93. At this time, even if the casing 91 pipe is flushed, the mounting pins 53 Is engaged with the pin engaging groove 15 through the pin insertion hole 21, so that the drill bit 17 does not come off the drive shoe 13.

The drilling water W passes through a water passage 37 provided in the leg 35 c of the bit connecting jig 35, passes through the water supply passage 27 of the valve seat 25, and flows from the ejection hole 19 of the drill bit 17 to the ground. When the water supply is stopped, the ball valve 31 moves to the valve seat 25 due to the groundwater pressure and the spring force of the spring 29.
The water supply passage 27 is closed to prevent the backflow of the muddy water into the drill bit 17.

After completion of the drilling, the bit connecting jig recovery jig 4 is connected from the ground via the PC steel wire 73 as shown in FIG.
1 is inserted into the casing tube 91, and the locking claw 43 of the bit connecting jig collecting jig 41 is elastically locked to the locking claw 39 of the bit connecting jig 35 as shown in FIG.

When the bit connecting jig collecting jig 41 is gradually pulled upward in this state, the wire 55 attaches the attaching pin 53 against the spring force of the spring 51 as shown in FIG. It is retracted into the pin housing 49 to release the engagement with the pin engagement groove 15.

Then, the stopper member 47 of the locking portion 35b
Is in contact with the peripheral edge of the opening of the jig body 35a, the mounting pin 53 is completely disengaged from the pin insertion hole 21 and retreats into the mounting pin housing 49, and at this time, the stopper 67 is moved to the locking portion 35b. To prevent the device from falling down.

Therefore, if the bit connecting jig collecting jig 41 is further pulled upward in this state, the entire bit connecting jig 35 is pulled upward and collected on the ground as shown in FIGS. You.

Thereafter, as shown in FIG. 12, an anchor tension member 97 is inserted into the casing pipe 91 to grout the grout material G.
13, the drill bit 17 is separated from the drive shoe 13 and is left in the anchor hole 95, and is buried in the anchor hole 95 by the grout material G. Will be done.

As described above, the drilling apparatus according to this embodiment is
When drilling the ground 93, the mounting pin 5 of the bit connecting jig 35
3 is engaged with the pin engaging groove 15 through the pin insertion hole 21 to connect the drive shoe 13 and the drill bit 17. After the drilling is completed, the bit connecting jig recovery jig 41 collects the bit connecting jig 35. When the hole is collected, the connection state is released.By using such a drilling device for the construction of the earth anchor, the casing tube 91 can be flushed at the time of drilling, and the casing tube 91 can be removed. The drill bit 17 and the drive shoe 13 can be easily separated at the time of pulling out, and as a result, the workability of the earth anchor has been dramatically improved as compared with the related art.

In the above embodiment, the present invention has been described using the drill bit 17 in which the check valve 23 is built in the cylindrical portion 17b. However, the drill device according to the present invention employs such a check. Of course, the present invention can be applied to a disposable bit without the valve 23.

[0040]

As described above, by using the drilling device according to each claim for the construction of the earth anchor, the casing pipe can be flushed at the time of drilling the ground, and the casing pipe can be removed at the time of pulling out the casing pipe. Since the drill bit and the drive shoe can be easily separated,
The workability of the earth anchor has been dramatically improved compared to the past.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a drilling device according to claims 1 and 2;

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a cross-sectional view of the drilling device showing a state in which a locking portion of the bit connecting jig is pulled up by a bit connecting jig collecting jig.

FIG. 4 is a cross-sectional view of the drilling machine showing a state in which the entire bit connecting jig is pulled up by a bit connecting jig collecting jig.

FIG. 5 is a partially cutaway side view of the bit connecting jig collecting jig.

FIG. 6 is a sectional view taken along line VI-VI of FIG. 5;

FIG. 7 is a bottom view of a locking claw of the bit connecting jig collecting jig.

FIG. 8 is a schematic diagram showing a state of drilling of the ground by the drilling device of the present embodiment.

FIG. 9 is a schematic view showing a state where a bit connecting jig collecting jig is inserted into a casing tube.

FIG. 10 is a schematic view showing a state in which a locking claw of a bit connecting jig collecting jig is locked to a locking claw of the bit connecting jig.

FIG. 11 is a schematic view showing a state in which the bit connecting jig is being collected by the bit connecting jig collecting jig.

FIG. 12 is a schematic view showing a state in which a grout material is injected under pressure after insertion of an anchor tension material.

FIG. 13 is a schematic view showing a state where the casing tube is being pulled out.

FIG. 14 is a perspective view of a conventional kronen bit, a drive shoe, and a casing tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 13 Drive shoe 15 Pin engagement groove 17 Drilling bit 17a Head 17b Cylindrical part 19 Jet hole 21 Pin insertion hole 23 Check valve 35 Bit connecting jig 35a Jig body 35b Locking part 35c Leg 39,43 Stop claw 41 Bit connecting jig recovery jig 47 Stopper member 51, 85 Spring 53 Mounting pin 55 Wire 63 Stopper device 71 Support portion 73 PC steel wire 75 Guide plate 77 Fixed arm member 81 Movable arm member 91 Casing tube 93 Ground 95 Anchor Hole

──────────────────────────────────────────────────続 き Continuing on the front page (72) Masakazu Fujita 6-22, Matsugaeda-cho, Kita-ku, Osaka, Osaka Japan Basic Technology Co., Ltd. (72) Masanobu Mai Matsugae-cho, Kita-ku, Osaka, Osaka No. 6-22 Inside Japan Basic Technology Co., Ltd. (56) References JP-A-7-166545 (JP, A) JP-A-7-3787 (JP, A) JP-A-6-306859 (JP, A) 55-96990 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 5/80 E21B 7/20 E21B 7/00 E21B 10/62

Claims (2)

(57) [Claims] 1. A drive shoe screwed to a tip of a casing tube connected to a drilling machine and having a pin engagement groove formed on an inner periphery thereof, meshed with the drive shoe in the axial direction and connected to the tip. A drilling bit having a water ejection hole for drilling formed in a head arranged at the tip of the drive shoe, and a plurality of pin insertion holes formed in a peripheral wall of a cylindrical portion inserted into the drive shoe; A bit connecting jig which is disposed in the hole bit and has a mounting pin inserted through the pin insertion hole of the drill bit and engaged with the pin engagement groove of the drive shoe; A bit connecting jig recovering jig for collecting the bit connecting jig, wherein the mounting pin is retracted from the pin insertion hole of the drill bit by pulling up the bit connecting jig by the bit connecting jig recovering jig. Features That drilling equipment. 2. A bit connecting jig disposed in a drill bit, a locking portion provided with a locking claw and slidable upward, and a mounting pin being urged outward to drive the mounting pin. A bit connecting jig recovering jig, which is provided with a spring for engaging and retaining the pin engaging groove of the shoe and a wire connecting the mounting pin and the engaging portion, is inserted into the casing tube so as to be able to move up and down. The claw is provided with a locking claw which can be elastically locked, and the mounting pin is drilled through a wire by pulling up the locking portion by the bit connecting jig recovery jig locked via the locking claw. 2. The drilling device according to claim 1, wherein the drilling device retreats from the pin insertion hole of the bit.