JPH07238541A - Excavating device - Google Patents

Abstract

PURPOSE:To increase the workability of an earth anchor, by retracting a fixing pun engaging in the groove to fit to the pin of a drive shoe from a pin-insertion hole of an excavating bit, when a bit-connection tool by collecting tool thereof is lifted. CONSTITUTION:In order to install an earth anchor by use of an excavating device, at first, a notch 87 of an excavating bit 17 is forced to axially engage with a notch 89 of a drive shoe 13. Next, a fixing pin 53 of a bit-connection tool 35 is engaged in the groove 15 to fit to the pin of the drive shoe 13 through a pin-insertion hole 21 of the excavating bit 17. Next, the drive shoe 13 is screwed up the front end of a casing pipe connected to the excavating machine and the casing pipes are jointed by turns in accordance with the excavated depth to excavate an anchor hole in the ground while feeding drilling water into the casing pipe. In this time, even in a flashing motion of the casing pipes, since the fixing pin 53 is engaged with the groove 15 through the pin-insertion hole 21, the excavation bit is prevented from slipping out of the drive shoe 13.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Conventionally, the earth anchor construction method has been widely used for the purpose of preventing falls of retaining walls and bridge piers, buoyancy of dock floor boards, and ground slip.

In this earth anchor construction method, water for drilling is injected into a casing pipe connected to a drilling machine, and the ground is drilled with a drilling bit at the tip of the casing pipe, and the anchor cable is drilled in the drilled anchor hole. After inserting (steel wire),
By pulling out the casing pipe and injecting grout material into the anchor hole under pressure to create an anchor body in the ground, the ground and the structure are connected. Are sequentially connected accordingly.

Thus, conventionally, when constructing an earth anchor on soft ground, a so-called discarded bit such as a Kronen bit has been used as a drill bit. As shown in FIG. 14, the Kronen bit 1 is attached to the casing tube 3 via a drive shoe 5 screwed to the insertion side end of the casing tube 3, and is inserted into the drive shoe 5.
a and a head 1b arranged at the tip of the drive shoe 5. Then, the cylindrical portion 1a is inserted into the drive shoe 5, and the notch portion 7 provided at the rear end of the head portion 1b is meshed with the notch portion 9 at the tip of the drive shoe 5 in the axial direction (drilling direction). The rotation of the casing tube 3 is transmitted to the Kronen bit 1 by connecting the drive shoe 5 to the drive shoe 5.

When the casing pipe 3 is pulled out by injecting the grout material, the Kronen bit 1 is separated from the drive shoe 5 and is left in the anchor hole, and is buried by the grout material. There is. In the figure,
Reference numeral 11 is a jetting water ejection hole.

[0006]

As described above, conventionally, the Kronen bit 1 is connected to the drive shoe 5 by axially engaging with it when the earth anchor is installed, and also when the casing pipe 3 is pulled out. It has a structure that separates from the drive shoe 3.

By the way, when drilling the ground, for example, when the casing pipe 3 is tightened by the drilling, such as when hitting a hard rock or when the casing pipe 3 is tightened by the drilling, such as a gravel layer, the casing pipe 3 is flushed. It is necessary to apply a striking force to the drilling bit and to move the casing pipe up and down to eliminate slime on the outer periphery of the casing pipe to dig the ground.

However, in the conventional connection structure of the Kronen bit 1 and the drive shoe 5 as described above, the Kronen bit 1 is separated from the drive shoe 5 by flushing the casing pipe 3.
Also, remove the Kronen bit 1 once, and drive shoe 5
Since it is difficult to connect to the disk, the connection structure of the Kronen bit and the drive shoe capable of flushing operation has been desired.

The present invention has been devised in view of the above circumstances, and enables the flushing operation of the casing pipe when the anchor hole is drilled, and the detachment of the drill bit and the drive shoe when the casing pipe is pulled out. An object of the present invention is to provide a drilling device for earth anchor construction that can be easily performed.

[0010]

In order to achieve such an object, a boring device according to a first aspect of the present invention is provided with a pin engaging groove which is screwed to a tip of a casing pipe connected to a boring machine and which is formed on an inner periphery thereof. And a drive shoe formed with the drive shoe, which is axially meshed with the drive shoe and connected to the tip of the drive shoe. A water ejection hole for drilling is formed in the head located at the tip of the drive shoe, and the drive shoe is inserted into the drive shoe. A drill bit with a plurality of pin insertion holes formed on the peripheral wall of a cylindrical part, and a pin that is placed inside the drill bit and inserted through the pin insertion hole of the drill bit to engage with the pin engagement groove of the drive shoe. A bit connecting jig with a mounting pin attached and a bit connecting jig collecting jig that is vertically inserted into the casing pipe and collects 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 present invention, the bit connecting jig arranged in the drilling bit has a locking portion provided with a locking claw and slidable upward, and the mounting pin is biased outward. A bit connecting jig collecting jig that is equipped with a spring that engages and holds the mounting pin in the pin engaging groove of the drive shoe and a wire that connects the mounting pin and the locking portion and that is vertically inserted into the casing pipe is The above-mentioned locking claw is provided with a locking claw that can be elastically locked, and the mounting pin pulls up the locking part by the bit connecting jig recovery jig locked through the locking claw to pull the wire. It is characterized in that it retreats from the pin insertion hole of the hole drilling bit through.

[0012]

According to the hole drilling device of the present invention, when 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 hole drilling bit, the drive shoe is formed. The drilling bits will be connected.

Therefore, if the drive shoe to which the drill bit is connected is screwed to the tip of the casing pipe and the drilling water is fed into the casing pipe to drill the ground, the anchor hole is formed in the ground. Will be drilled. Even when the casing pipe is flushed during drilling, the drill bit does not come off the drive shoe because the mounting pin engages with the pin engaging groove through the pin insertion hole.

After the drilling is completed, the bit connecting jig collecting jig is inserted into the casing pipe, and the bit connecting jig is pulled up by the bit connecting jig collecting jig. The drive shoe and the drill bit are released from the connected state by retracting.

Then, if an anchor tension material is inserted into the anchor hole and the grout material is injected under pressure and the casing tube is pulled out, 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.

According to the hole drilling bit of the second aspect,
After engaging the locking claws of the bit connection jig recovery jig inserted in the casing pipe with the locking claws of the locking part of the bit connection jig, pull up the locking parts with the bit connection jig recovery jig. If
The wire retracts the mounting pin from the pin insertion hole against the spring force of the spring, and releases the connection between the drive shoe and the drill bit.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows an embodiment of a hole drilling device according to claim 1 and claim 2, in which 13 is a drive shoe screwed to the tip of a casing pipe, and has a single inner periphery as in the conventional case. A book pin engagement groove 15 is formed. The drill bit 17 is axially engaged with and connected to the tip of the drill bit 17.

The drill bit 17 is composed of a head portion 17a arranged at the tip of the drive shoe 13 and a cylindrical portion 17b inserted into the drive shoe 13, and the head portion 17 is formed.
2a is provided with a plurality of holes 19 for drilling water, and FIG.
As shown in FIG. 5, pin insertion holes 21 are provided at 120 ° intervals on the peripheral wall of the cylindrical portion 17b so as to correspond to the pin engaging grooves 15. Then, a check valve 23 similar to the conventional one is mounted in the tubular portion 17b on the back surface side of the head portion 17a.

That is, in FIG. 1, 25 is a valve seat having a water supply passage 27 which tapers downward and is provided in the center, and the valve seat 25 is fixed to the inner periphery of the cylindrical portion 17b. There is. A ball valve 31 biased by a spring 29 stretched between the head 17a and the back surface of the head 17a 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 the chain double-dashed line, the water pressure causes the ball valve 31 to move downward against the spring force of the spring 29, and the water supply passage 27 is opened. In the figure, 33 is an O-ring that seals the gap between the drive shoe 13 and the drill bit 17.

A bit connecting jig 35 having the same center axis as that of the drive shoe 13 is provided above the check valve 23.
Are arranged. The bit connecting jig 35 includes a bottomed cylindrical jig main body 35a, a locking portion 35b that is inserted into an upper portion of the jig main body 35a and can slide upward, and the jig main body 3a.
5a and a cylindrical leg portion 35c fixed to the lower portion of the casing 5a. Water holes 37 through which the drilling water W fed into the casing pipe passes are formed on the peripheral wall of the leg portion 35c at intervals of 90 °. It is provided by opening.

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

49 is a jig body 3 with a 120 ° interval.
A cylindrical mounting pin accommodating body mounted on the peripheral wall of 5a. In each mounting pin accommodating body 49, a mounting pin 53 biased outward by a spring 51 is mounted. Each mounting pin 53 urged by the spring 51 is inserted into the pin insertion hole 21 and is engaged with the pin engagement groove 15, and thus the mounting pin 53 is pinned through the pin insertion hole 21. Engagement groove 1
By engaging 5 the drill bit 17 is connected to the drive shoe 13.

Then, the engaging portion 35b and each mounting pin 5
3 are connected by the wires 55 arranged in the jig body 35a and the locking portion 35b, respectively. As described above, as the locking portion 35b is pulled up by the bit connecting jig collecting jig 41, 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 engagement groove 15. Then, as shown in FIG. 3, the stopper member 4 of the locking portion 35b is provided.
In the state where 7 is in contact with the peripheral edge of the opening of the jig body 35a, the mounting pin 53 is completely removed from the pin insertion hole 21 and retracts into the mounting pin accommodating body 49, and in this state, the bit connecting jig is recovered again. When the jig 41 is pulled up, the entire bit connecting jig 35 is pulled up as shown in FIG. The end portions of the wires 55 are respectively attached to the locking portions 35b and the mounting pins 53 by the epoxy adhesive 57.
Are fixed to the mounting recesses 59 and 61.

Further, in FIG. 1, 63 is the mounting pin housing 4 described above.
9 is a stopper device of the locking portion 35b mounted above the
The stopper device 63 includes a stopper 67 that is constantly urged into the jig body 35a by a spring 65, and the stopper member 47 resists the spring force of the spring 65 to move the stopper 67 as the locking portion 35b rises. After pressing and passing through the stopper member 47, the stopper 67 causes the spring 65 to
Of the locking portion 3 by projecting again into the jig body 35a by the restoring force of
5b is prevented from falling downward. In addition, reference numeral 69 in FIG. 1 denotes an O-ring that seals between the jig body 35a and the locking portion 35b.

FIG. 5 is a partially cutaway side view of the bit connecting jig collecting jig 41 which is vertically inserted into the casing pipe. In FIG. 5, 71 is one end of the PC steel wire 73 by the epoxy adhesive 57. Four guide plates 75 are attached to the outer periphery of the connected cylindrical support portion at intervals of 90 °. These guide plates 75 are for arranging the bit connecting jig collecting jig 41 in the center of the casing pipe when the bit connecting jig collecting jig 41 is inserted into the casing pipe. The dimension m between the tops 75a is set to be slightly shorter than the inner diameter of the casing tube. A fixed arm member 77 is fixed to the lower portion of the support portion 71.

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

In the figure, reference numeral 81 is a movable arm member, which is shown in FIG.
The upper portion of the movable arm member 81 having a U-shaped cross section is fitted into the fixed arm member 77 and is axially attached to the fixed arm member 81 via a mounting shaft 83 as shown in FIG. The claw member 79 is also attached to the arm portion 81a extending to face the portion 77a. Then, a spring 85 is stretched between the rear surface portions 77b and 81b of the arm members 77 and 81 formed in a U-shaped cross section, and the movable arm member 81 is stretched by the spring 85.
Is urged in the direction of arrow A around the mounting shaft 83, and both arm portions 77a and 81a are kept in parallel.

When the bit connecting jig 35 is recovered, when the engaging claws 43 of the bit connecting jig recovering jig 41 inserted into the casing pipe contact the outer circumference of the engaging claws 39 of the bit connecting jig 35, Spring 8 as indicated by the chain double-dashed line
The movable arm member 81 moves in the direction of the arrow B about the mounting shaft 83 as a center of rotation against the spring force of No. 5, and the locking claw 43 is locked to the locking claw 39. The restoring force of 85 elastically restores the state shown by the solid line. 7 is a bottom view of the locking claw 43.

In addition, in FIG. 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 pipe is transmitted to the drill bit 17 by engaging both the cut portions 87 and 89 in the axial direction (drilling direction) at the notched portion.

Since the drilling device according to the present embodiment is constructed in this way, in order to construct an earth anchor using the drilling device, first, as shown in FIG.
7 notch 87 and drive shoe 13 notch 89
Are engaged with each other in the axial direction, 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.
The drive shoe 13 and the drill bit 17 are now connected.

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

Further, the drilling water W passes through the water holes 37 provided in the leg portions 35c of the bit connecting jig 35, the water supply passage 27 of the valve seat 25, and the jet hole 19 of the hole drilling bit 17 to the ground. However, when the water supply is stopped, the ball valve 31 is moved to the valve seat 25 by the groundwater pressure and the spring force of the spring 29.
The water supply passage 27 is closed to prevent the backflow of muddy water into the drill bit 17.

After the completion of drilling, as shown in FIG. 9, the bit connecting jig collecting jig 4 is connected from the ground through the PC steel wire 73.
1 is inserted into the casing pipe 91, and as shown in FIG. 10, the locking claw 43 of the bit connecting jig recovery jig 41 is elastically locked to the locking claw 39 on the bit connecting jig 35 side.

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

Then, the stopper member 47 of the locking portion 35b
In a state of abutting against the peripheral edge of the opening of the jig body 35a, the mounting pin 53 is completely removed from the pin insertion hole 21 and retracts into the mounting pin accommodating body 49, and at this time, the stopper 67 locks the locking portion 35b. To prevent it from falling down.

Therefore, if the bit connecting jig collecting jig 41 is further pulled up in this state, the entire bit connecting jig 35 is pulled up and collected on the ground as shown in FIGS. 4 and 11. It

After that, as shown in FIG. 12, the anchor tension member 97 is inserted into the casing pipe 91 and the grout member G is inserted.
When the casing pipe 91 is pulled out as shown in FIG. 13, the drill bit 17 is separated from the drive shoe 13 and remains 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 device 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, and after the drilling is completed, the bit connecting jig recovery jig 41 is used to connect the bit connecting jig 35. Since the connected state of the casing pipe 91 is released at the time of collecting, the casing pipe 91 can be flushed at the time of drilling by using such a drilling device for construction of the ground anchor, and It is possible to easily separate the drill bit 17 and the drive shoe 13 at the time of pulling out, and as a result, the workability of the ground anchor is dramatically improved as compared with the conventional one.

In the above embodiment, the present invention has been described by using the drilling bit 17 having the check valve 23 built in the cylindrical portion 17b. However, the drilling device according to the present invention is such a check valve. Of course, the present invention can also be applied to a disposable bit in which the valve 23 is not mounted.

[0040]

As described above, by using the boring device according to each claim for construction of the ground anchor, the flushing operation of the casing pipe becomes possible at the time of boring the ground, and at the time of pulling out the casing pipe. Since it is easy to separate the drill bit and the drive shoe,
The workability of the earth anchor has been dramatically improved compared to the past.

[Brief description of drawings]

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

FIG. 2 is a sectional view taken along line II-II in 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 the bit connecting jig collecting jig.

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

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

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

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

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

FIG. 9 is a schematic view showing a state in which a bit connecting jig collecting jig is inserted into a casing pipe.

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

FIG. 11 is a schematic view showing a state where the bit connecting jig collecting jig collects the bit connecting jig.

FIG. 12 is a schematic view showing a state in which the grout material is pressure-injected after the anchor tension material is inserted.

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

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

[Explanation of symbols]

 13 Drive Shoe 15 Pin Engagement Groove 17 Drill Bit 17a Head 17b Cylindrical Portion 19 Jet Hole 21 Pin Insertion Hole 23 Check Valve 35 Bit Connecting Jig 35a Jig Body 35b Locking Part 35c Leg 39, 43 Engagement Stopper 41 Bit connection 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 pipe 93 Ground 95 Anchor Hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masakazu Fujita 6-22 Matsugaeda-cho, Kita-ku, Osaka-shi, Osaka Within Japan Basic Technology Co., Ltd. (72) Masanobu Mayi 6 Matsugae-cho, Kita-ku, Osaka No.22 in Japan Basic Technology Co., Ltd.

Claims (2)

[Claims] 1. A drive shoe, which is screwed to the tip of a casing pipe connected to a hole drilling machine and has a pin engaging groove formed in the inner periphery thereof, and which is axially meshed with the drive shoe and connected to the tip thereof. , A drill bit that has a water ejection hole for drilling formed in the head located at the tip of the drive shoe, and a plurality of pin insertion holes formed in the peripheral wall of the cylindrical part that is inserted into the drive shoe. The bit connecting jig, which is arranged in the hole bit, has a mounting pin that is inserted through the pin insertion hole of the drill bit and engages with the pin engaging groove of the drive shoe, and is inserted into the casing pipe so as to be vertically movable. It is equipped with a bit connecting jig collecting jig for collecting the bit connecting jig, and the mounting pin is retracted from the pin insertion hole of the drilled bit by pulling up the bit connecting jig by the bit connecting jig collecting jig. Featuring That drilling equipment. 2. A bit connecting jig arranged in a drill bit comprises a locking portion provided with a locking claw and slidable upward, and a mounting pin biased outward to drive the mounting pin. The bit connecting jig recovery jig, which is equipped with a spring that engages and holds the pin engaging groove of the shoe and a wire that connects the mounting pin and the locking portion, is vertically inserted into the casing pipe. Equipped with a locking claw that can be elastically locked to the claw, and the mounting pin is drilled through the wire by pulling up the locking part with the bit connecting jig recovery jig locked through the locking claw. The boring device according to claim 1, wherein the boring device retracts from the pin insertion hole of the bit.