JP3222973B2 - Expanded drilling rig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an enlarged excavation apparatus for constructing an enlarged bulb into which a consolidation liquid is injected into a tip of a pile so as to exhibit a pile tip supporting force. Medium digging method
Used in industrial fields such as pre-boring root compaction.

[0002]

2. Description of the Related Art Conventionally, pre-cast piles, which have been driven by hitting, have been switched to a hole excavated in the ground for installation with low noise and low vibration, or to an embedded pile method in which piles are installed while excavating the ground. Is coming. The embedding pile method is classified into the middle digging method, pre-boring method, etc. In this, the tip of the pile is expanded and cement milk is injected to build an expanded bulb, and the pile and the supporting ground are integrated. There is a construction method in which the tip support force is developed by doing so. As an enlarged excavation bit used in such a construction method for enlarging the tip of a pile, a drill bit according to Japanese Patent Publication No. 3-61833 and the like in addition to Japanese Utility Model Laid-Open No. 1-79692 by the present inventor has been known.

[0003]

However, the above-mentioned enlarged excavation bit has a structural problem that the enlarged blade is not sufficiently opened or the enlarged blade is not retracted to the original state after the end of the enlarged excavation. . For example, Japanese Utility Model Application 1-79692
According to the publication, despite the structure in which the expanding blade is retracted by the earth pressure resistance, the earth pressure resistance in the excavated hole that has been enlarged at the end of the expanded excavation has already weakened, Did not return to the state. For this reason, when pulling up the enlarged excavation bit, problems such as collapse of the hole wall were caused. Also, it is difficult to confirm whether or not the enlarged bulb portion is formed by the extended excavation, and this is one of the drawbacks of the method of consolidation.

[0004] The present invention overcomes the above-mentioned problems. In addition to opening the expanding blade so that the excavation can be performed at the tip of the pile and enabling the state to be confirmed from the ground, the present invention also provides an expanded bulb. It is an object of the present invention to provide an enlarged excavator in which an enlarged blade is reliably retracted to an original state after forming a portion.

[0005]

Expanding the drilling apparatus of the present first invention, in order to solve the problem] is provided with a drilling blades around Cylindrical axis and bisected to as across the drill bit forming the digging edge to the drilling blade lower end Upper and lower bits, a connection joint for rotatably joining the upper bit and the lower bit to each other, and loosely inserted into a long hole formed on the cylindrical shaft side surface of the upper bit or the lower bit, and fixed to the connection joint. A guide shaft configured to limit the rotation range of the connection joint by a long hole,
An enlarged blade rotatably attached to a spindle provided on a bracket of the upper bit or the lower bit, and a link mechanism connecting the guide shaft and the enlarged blade so that the enlarged blade swings by rotation of the upper bit. provided, when the upper bits in a forward rotation, by the guide shaft is locked at one end of the slots, the upper and lower bits hold the drilling blade shape before the division, the link mechanism is enlarged blade digging the blade while forced housing, when the upper bit is reversely rotating, projecting outwardly of the enlarged blade drilling blade at the link mechanism, in order to hold the projecting state, as the guide shaft is engaged with the other end of the elongated hole It is characterized by comprising. Here, “forward rotation” refers to the rotation direction of the motor during excavation up to the bottom (hereinafter, “forward rotation”). “Reverse rotation” refers to the rotation direction of the motor when performing enlarged excavation after the lower bit reaches the bottom (hereinafter, “reverse rotation”).

According to a second aspect of the present invention, there is provided the enlarged excavator according to the first aspect, wherein the upper and lower bits, the connection joint, the guide shaft,
At least one of the link mechanisms is provided with a micro switch, and when the guide shaft is locked at one end of the long hole by the forward rotation of the upper bit, this micro switch is activated to indicate that the extension blade has been completely extended. The signal is transmitted to the ground through the shaft and the hollow part of the screw rod.

[0007]

According to the present invention, when the screw rod of the excavator is rotated forward for excavation, the upper bit fixed to the screw rod also rotates forward. And the guide shaft is
When locked at one end , the lower bit also begins to rotate.

The upper and lower bits are aligned by being locked at one end of the elongated hole, and the excavation blade shape before being divided is formed, so that excavation can be performed smoothly . When the upper and lower bits rotate together, the link mechanism pulls the excavating blade to forcibly house the excavating blade in the excavating blade, so that the excavating blade does not hinder the excavation.

On the other hand, when the lower bit reaches the drilling bottom of a predetermined depth and enters into the extended excavation to obtain an enlarged bulb portion, the enlarged excavator is once lifted and dropped on the drilled bottom. This will cause the lower bit to pierce the bottom. When this state is secured and the screw rod is reversed, the upper bit is reversed. But,
The lower bit cannot penetrate because it penetrates the bottom and remains stopped. Therefore, the link mechanism causes the enlarged blade to protrude outside the excavating blade. When the projection of the enlarged blade is completed, the guide shaft comes into contact with the other end of the elongated hole .

[0010] Here, a microswitch is attached to any of the upper and lower bits, the hollow joint, the link mechanism, and the stop, and when the microswitch is actuated at the time of the contact, the state is transmitted to the ground. Therefore, it is possible to confirm that the extension blade is completely protruded from the ground . When the screw rod is rotated forward after the bulb portion is formed by the enlarging blade, the upper bit also rotates forward. When the upper bit rotates forward, the link mechanism forcibly retracts the enlarged blade into the excavating blade.

According to such an enlarged excavator, the number of parts is small and the structure is simple . Furthermore, in the enlarged large excavator provided with the expansion auxiliary blade, the expansion auxiliary blade expands at the time of normal rotation, and expands more than the drill bit diameter. The load on the magnifying blade is small.

[0012]

The present invention will be described below in detail with reference to examples. (1) Embodiment 1 a. 1 to 7 show an embodiment of the present enlarged digging apparatus. The enlarged drilling rig A includes a drill bit 1, a hollow joint 2,
Enlarging blade 3, link mechanism 4, stopper 55, and stopper 5
6, 57.

The drill bit 1 has a cylindrical shaft 11 (outer diameter: 27).
A digging blade 12 (excavation outer diameter D: about 690 mmφ) twisted by about 180 degrees around 3φ, wall thickness: 30 mm) is formed, and a digging blade 13 is provided at a lower end of the digging blade. The excavating blade 12 is connected to the blade 91 at the lower end of the screw rod 9 (FIG. 7). This is to make it easy to discharge the excavated soil upward in the normal rotation (in this embodiment, right rotation). At the bottom of the cylindrical shaft 11, a blind plate is fixed by welding to form a bottomed cylinder.
There is an opening valve 111 having an opening formed near the lower end of the cylindrical shaft 11 and covered with rubber packing. This is to prevent excavated soil from entering during excavation and to discharge the root compaction liquid that has passed through the inside of the screw rod 9 after excavation to the shaved bottom.

Reference numeral 15 denotes a hexagonal joint. Screw rod 9 provided with spiral blades in hollow pipe
Is to be joined. The joint 15 is hollow and electrically connects the cylindrical shaft 11 and the screw rod 9. The excavation bit 1 is cut so as to traverse substantially at the center, and is divided into an upper bit 1a and a lower bit 1b (FIG. 1). But,
The upper bit 1a and the lower bit 1b have a configuration in which the cut portions are joined by the hollow joint 2 (FIG. 6).

The hollow joint 2 is a cylindrical body, and has annular grooves 21 and 21 formed on the side surfaces (FIG. 5). The hollow joint 2 inserts the upper part into the cylindrical shaft 11 of the upper bit 1a and fixes it by welding, while inserting the lower part into the cylinder of the lower bit 1b,
Using the through hole 112 provided in the lower bit 1b, the bolt 11
3 and the lower bit 1b is joined (FIG. 6). 6 bolts 1
13 engages with the annular groove 21. Thus, the upper bit 1a and the lower bit 1b do not come off in the axial direction via the hollow joint 2, and are rotatably attached to each other about the hollow joint 2.

Reference numeral 3 denotes a claw-shaped enlarged blade (FIG. 2).
Brackets 31, 31 are formed above the lower bit 1b, and the enlarged blade 3 is rotatably mounted on a spindle 32 provided on the bracket (FIG. 4). In the present embodiment, two enlarged blades 3 are arranged around the cylindrical axis 11 at an interval of 180 degrees. Support shaft 32
When the enlarged blade 3 is rotated around the center, the minimum rotation outer diameter of the enlarged blade 3 around the cylindrical shaft 11 becomes slightly less than 690 mmφ.
Since the enlarged blade 3 has a curved shape in an arc shape, it can be accommodated within the outer diameter D of the excavation by the excavation blade 12 (FIG. 2). On the other hand, the maximum rotation outer diameter of the enlarged blade 3 about the cylindrical shaft 11 is about 1200 mmφ. At this time, the enlarged blade is pile 8
The outermost diameter (approximately 1000 mmφ) of FIG.

The link mechanism 4 includes a cylindrical shaft 1 of the upper bit 1a.
1 is rotatably mounted on one end of a lever 42 on the protruding piece 41, and the other end of the lever 42 is connected to the support shaft 3 of the enlarged blade 3.
It consists of a mechanism that is axially attached to the overhanging portion 43 that is closer to two. When the upper bit 1a is normally rotated by the link mechanism 4, the enlarged blade 3 rotates counterclockwise about the support shaft 32 (FIG. 2). When the upper bit 1a rotates in the reverse direction (meaning left rotation in this embodiment), the enlarged blade 3 is configured to rotate right around the support shaft 32 (FIG. 3).

The stopper 55 is provided on the cylindrical shaft 1 of the lower bit 1b.
1 is provided near the upper edge. The upper end of the stopper 55 has a shape protruding to the position of the protruding piece 41 formed on the upper bit 1a (FIG. 4). When the upper bit 1a rotates forward, the stopper 55 locks the projecting piece 41 of the upper bit 1a. The mounting position of the stopper 55 is set so that the enlarged blade 3 enters the outer diameter D of the excavating blade 12 (FIG. 2). Also, at this time, the upper bit 1a and the lower bit 1b that are divided into two are set so as to form the excavation blade shape before the division (FIG. 1). In the present embodiment, the stopper 55 is mounted at a position where the bracket 31 is rotated forward by approximately 90 degrees from the position of the bracket 31 (FIG. 4).

The stop pieces 56 and 57 are block pieces provided on the lower bit 1b (the stop piece 56 is omitted in FIG. 2). When the upper bit 1a reversely rotates, the projecting piece 41 and the enlarged blade 3
For locking. Fix the lower bit 1b,
When the upper bit 1a is reversed, the enlarged blade 3 projects outward of the excavating blade by the link mechanism 4. In the most protruding state, the stop piece 56 projecting from the upper bit 1a locks the protruding piece 41 and the stop piece 57 provided near the support shaft 32.
Also has an arrangement for locking the enlarged blade 3 (FIG. 3). If the mechanical strength is sufficient, either of the stopper pieces 56 and 57 may be omitted.

Reference numeral 561 denotes a limit type microswitch (FIG. 3). The microswitch 561 is attached to a stop piece 56 that contacts the protrusion 41. When the protruding piece 41 hits the microswitch 561 and the enlarged blade 3 protrudes outward, a signal is transmitted to display a lamp on the operation panel of the ground operator. Micro switch 561
A substrate with a backup power supply (not shown) is incorporated in the vicinity. The detected radio signal is transmitted wirelessly to the ground by skipping the hollow joint 2, the cylindrical shaft 11, and the hollow portion of the screw rod 9, which serve as a supply path of the consolidation liquid, from the stopper 56. In this embodiment, the stopper 55 is also provided with the projecting piece 4.
A micro switch 551 for notifying that the blade 1 has come into contact is attached, and the display panel on the ground also notifies that the enlarged blade 3 is retracted.

B. Operation of Enlarged Drilling Apparatus The operation of the enlarged excavation apparatus when the construction by the middle digging and consolidation method is performed at the site where the pile is to be embedded by using the enlarged excavation apparatus configured as described above (FIGS. 7 to 9). Open-end pile 8
Has an outer diameter of 1000 mmφ and an inner diameter of 740 mmφ. The pile tip ground is excavated through the hollow portion of the pile 8, and the pile body is laid while discharging excavated soil from the pile upper part.

First, the motor of the excavator is started to form a pile hole, and the screw rod 9 is rotated forward to excavate to a desired depth (FIG. 7). In this excavation process, the upper bit 1a fixed to the screw rod 9 also rotates forward.
Here, since the projecting piece 41 of the upper bit 1a presses the stopper 55 of the lower bit 1b, the lower bit 1b to which the stopper 55 is fixed is also urged in the forward direction (FIG. 2). The external force to be pressed is the upper bit 1a and the lower bit 1
b acts as a force for maintaining the shape of the excavating blade before division.
Therefore, the excavated soil excavated by the excavation blade 13 is smoothly transported upward by the excavation blades 12. Further, since the excavation proceeds while the protruding piece 41 presses the stopper 55, the enlarged blade 3 is kept in a state of being forcibly stored in the excavation blade 12 by the link mechanism 4. Therefore, a hole of about 690φ is dug without difficulty.

When the predetermined depth is reached, the next operation is started. The entire enlarged excavator A is lifted to some extent and dropped. Then, the excavation blade 13 pierces the new tip ground 81 by its own weight (FIG. 8).

Thereafter, the screw rod 9 is reversed. The lower bit 1b cannot follow this rotation due to the bite of the excavating blade 13 into the tip ground 81, and only the upper bit 1a reverses. Accordingly, the enlarged blade 3 projects outward of the excavating blade 12 by the link mechanism 4 (FIG. 4). Only the upper bit 1a is reversed until the stop pieces 56 and 57 of the lower bit 1b lock the protruding piece 41 and the enlarged blade 3, and the link mechanism 4 projects the enlarged blade 3. Stop pieces 56 and 57 are projected pieces 41,
At the place where the enlarged blade 3 is locked, the enlarged blade 3 is approximately 1200 m.
The excavation diameter is mφ (FIG. 3). At this time, the projecting piece 41 comes into contact with the microswitch 561 provided on the stop piece 56 (FIG. 3), and the completely protruding expansion blade 3 means that the hollow joint 2, the cylindrical shaft 11, the screw rod 9 is transmitted using the hollow portion. The fact that the excavation can be performed is displayed on the operation panel on the ground.

Further, when the screw rod 9 reverses,
Eventually, the lower bit 1b could not resist and the upper bit 1a
Follows and begins to reverse. In this state, an enlarged bulb portion 82 larger than the drill bit diameter (about 690 mmφ) is formed while reversing and moving up and down (FIG. 9). While the supporting ground is enlarged and excavated by the protruding enlarging blade 3, cement milk is sent from the ground. Cement milk which becomes a root compaction liquid is discharged from the opening valve 111 via the screw rod 9, the upper bit 1a, the hollow joint 2, and the lower bit 1b.

When the predetermined enlarged bulb portion 82 is formed, the motor is switched to normal rotation. Then, the link mechanism 4 retracts the enlarged blade 3 into the excavating blade 12 (FIG. 2).
Should the upper and lower bits 1a and 1b rotate together, the excavating blade 12
If it is notified by the panel display on the ground that it is not stored in the inside, the enlarged excavator A is lifted slightly, then dropped, and the lower bit 1b is pierced into a new bottom. Next, when the motor is rotated forward, the upper bit 1a rotates forward with the lower bit 1b fixed, so that the enlarged blade 3 can be forced into the excavating blade 12 by the link mechanism 4.
Thus, when the enlarged excavator A is pulled up to the ground, an enlarged bulb that integrates the open-end pile and the supporting ground is constructed without any trouble of collapsing the hole wall or the like.

(2) Embodiment 2 In the present embodiment, the following enlarged auxiliary blade 121 is added to the enlarged excavator A of the first embodiment. That is, as shown in FIG. 10, after the excavating blade 12 of the lower bit 1b is cut out in a claw shape at the outer peripheral edge, a support shaft 122 is provided in this cutout portion, and an expansion assist that fits the support shaft 122 in the notch shape. The blade 121 is attached. In the stationary state, the original state of the excavating blade 12 is maintained. The expansion auxiliary blade 121 has a lower bit 1b.
When it rotates forward and receives earth pressure resistance, it has a structure that spreads. Then, the support shaft 112 is provided so that horizontal excavation can be performed.
Above the stop, a stop 119 formed by a part of the excavating blade 12
(FIG. 10). This is because the expansion auxiliary blade 121 can be excavated in the horizontal direction without being excessively raised.

The excavating operation of the enlarged excavator to which the auxiliary auxiliary blade 121 is attached is as follows. The basic operation is the same as that of the first embodiment. However, in the pile 8, even if it is rotated forward, the expansion auxiliary blade 121 rotates while being in contact with the inner wall of the pile. However, once out of the pile, the expansion auxiliary blades 121 receive the earth pressure resistance and each open horizontally about 100 mm. In addition to the excavation by the excavation blade 13 and the excavation blade 12, the enlarged excavation of the enlarged auxiliary blade 121 is added, and the friction cutter 83 (see FIG. 7).
Without using digging, the drilling hole corresponding to the pile diameter can be dug down only by the enlarged drilling device (FIG. 11). When the lower bit 1a reverses and rises, the expansion auxiliary blade 121 is turned over, and forms the original excavation blade 12 appearance. Therefore, when raising the enlarged excavator, etc.
No problem.

(3) Embodiment 3 a. 12 to 19 show one embodiment according to the present invention . The enlarged drilling rig A includes a drill bit 1, a connection joint 6,
It is composed of a guide shaft 7, an enlarged blade 3, and a link mechanism 4 '.

As in the second embodiment, the drill bit 1 has a drill blade 12 formed around a cylindrical shaft 11, and a drill blade 13 is provided at a lower end of the drill blade 12. Reference numeral 121 denotes an auxiliary auxiliary blade 121, and reference numeral 15 denotes a hollow hexagonal joint. The excavation bit 1 is cut so as to cross at substantially the center, and is divided into an upper bit 1a and a lower bit 1b (FIG. 12). Near the lower end of the cylindrical shaft of the upper bit 1a, 18
Two nozzles 114, 114 are formed at 0 degree intervals (FIG. 1).
3) This is covered with a rubber packing to apply an internal pressure to form an opening valve 118 that opens only outward. This is to prevent excavated soil from entering during excavation, and to discharge the consolidation liquid that has passed through the screw rod 9 to the shaved bottom after excavation. The upper bit 1a and the lower bit b have a configuration in which the cut portions are joined by the connection joint 6 (FIG. 13).

The connection joint 6 is a cylindrical body and is inserted into the cylindrical shaft 11 of the upper and lower bits 1a and 1b. The connection joint 6 is provided with a through hole 61 that is bifurcated from the upper surface to both side surfaces (FIGS. 13 and 14). The connection joint 6 has its upper portion welded and fixed to the cylindrical shaft 11 of the upper bit 1a such that the through-hole 61 and the hole of the nozzle 114 coincide with each other (FIGS. 13 and 14).

The diameter of the lower portion of the connection joint 6 is made smaller in a stepped manner. Female screws 62, 62 are provided above the step.
Are formed at a pitch of 180 degrees (FIG. 14). Reference numeral 63 indicates an O-ring groove. Reference numeral 64 denotes a cap-shaped joint receiver that is placed in the cylindrical shaft 11 of the lower bit 1b with the concave portion facing upward (FIG. 13). It is fixed to the cylindrical shaft 11 by welding . When the connection joint 6 is inserted into the cylindrical shaft 11 of the lower bit 1b, the bottom surface thereof abuts on the joint receiver 64 and is joined so as to create a slight clearance E between the upper and lower bits 1a, 1b. This is because the sliding surface is the lower surface of the connection joint 6 to reduce the rotational resistance between the upper and lower bits. In order to prevent foreign matter from entering the sliding surface, O
An O-ring (not shown) is fitted in the ring groove 63.

Near the upper end of the cylindrical shaft 11 related to the lower bit 1b, elongated holes 115, 11 elongated in the horizontal direction at 180-degree intervals are provided.
5 are formed (FIGS. 14 and 15). The opening angle of the long hole 115 is about 75 degrees, and the opening length is 120 mm.
Reference numeral 7 denotes a guide shaft in an eyebolt state. The guide shaft 7 is configured to be loosely inserted into the elongated hole 115 and screwed to the female screw 62 of the connection joint 6 (FIG. 14). In this way, the upper bit 1a and the lower bit 1b do not come off in the axial direction via the connection joint 6, and the guide shaft 7 is locked by the elongated hole 115, so that the opening range of the elongated hole (75) is restricted.
It can be mounted rotatably only within degree).

Reference numeral 3 denotes a claw-shaped enlarged blade (FIG. 1).
2). The enlarged blade 3 has a shape curved in an arc shape, and
(Fig. 16).
The lower bit 1b is rotatably supported by a support shaft 32 provided on a bracket 31 of the lower bit 1b. Enlarging blade 3 is 2 at 180 degree intervals
Arrange them individually.

The link mechanism 4 ′ rotatably mounts one end of a lever 42 on a guide shaft 7 screwed to the connection joint 6, and projects the other end of the lever 42 toward the support shaft 32 of the enlarged blade 3. It consists of a mechanism to be attached to the part 43 (FIG. 16). When the upper bit 1a rotates forward by the link mechanism 4 ', the enlarged blade 3 rotates counterclockwise about the support shaft 32 (FIG. 1).
6). When the upper bit 1a rotates in the reverse direction, the enlarged blade 3 rotates clockwise about the support shaft 32 (FIG. 1).
7).

Reference numerals 116 and 117 indicate limit type micro switches. It is attached to the cylindrical shaft 11 at both ends of the long hole 115. When the upper bit 1a rotates forward, the guide shaft 7 connected to the upper bit 1a contacts the microswitch 116 to notify the ground operator that the enlarged blade 3 has protruded outward and has been completed. Sends a signal and displays it on the operation panel on the ground. The detected radio signal is transmitted wirelessly to the ground by skipping the hollow portion of the cylindrical shaft 11 and the screw rod 9 (FIG. 19). By the way, expanding blade 3
Projecting outwardly, the expanding blade 3 and the nozzle 114
Are opposed to each other (FIG. 13). When the upper bit 1a is reversed, the micro switch 117
This is to notify that the device has been retracted.

B. Operation of the enlarged excavator The basic operation is substantially the same as that of the second embodiment. First, the screw rod 9 is rotated forward. In the pile 8, as shown in FIG. 12, when the enlarged excavator comes out below the pile, the enlarged auxiliary blade 121 receives the earth pressure resistance and opens. In such a state, excavation is performed to a desired depth. Expansion auxiliary blade 121
, An excavation hole having a size substantially equal to the diameter of the pile is obtained (FIG. 18).

When reaching the predetermined depth, the rotation of the screw rod 9 is stopped. Then, the entire enlarged excavator is lifted and dropped. Then, the excavation blade 13 pierces the new tip ground 81. Thereafter, the screw rod 9 is reversed. As the lower bit 1b bites into the tip ground 81, only the upper bit 1a is reversed. With the reverse rotation of the upper bit 1a, the guide shaft 7 connected to the upper bit 1a
However, the enlarged blade 3 projects outside the excavating blade 12 via the link mechanism 4 ′ (FIG. 19). Only the upper bit 1a is reversed until the guide shaft 7 is locked at one end of the elongated hole 115, and at the point where the upper bit 1a is locked, the enlarged blade 3 takes the maximum excavation diameter (FIG. 17). At this time, the guide shaft 7 contacts the micro switch 116. Then, the micro switch 116 operates to transmit the fact that the enlarged blade 3 has completely protruded outward by using the hollow portion of the cylindrical shaft 11 and the screw rod 9.

Further, when the screw rod 9 is reversed,
The lower bit 1b cannot withstand, and finally follows the upper bit 1a and the lower bit 1b also reverses. When the screw rod 9 is reversed in this state and the enlarged excavator is moved up and down, an enlarged bulb portion 82 is formed (FIG. 19). Since an excavation hole having a diameter approximately equal to the pile diameter has already been obtained by the expansion auxiliary blade 121, the force required for the expansion blade 3 to excavate is reduced as compared with the first embodiment.

While the supporting ground is expanded and excavated by the protruding enlarging blade 3, cement milk is sent from the ground.
Cement milk is screw rod 9, upper bit 1a
The gas is discharged from the opening valve 118 via the cylindrical shaft 11, the through hole 61 of the connection joint 6, and the nozzle 114.

When the predetermined enlarged bulb portion 82 is formed, the screw rod 9 is switched to the normal rotation. Then, the guide shaft 7 retracts the enlarged blade 3 into the excavating blade 12 via the link mechanism 4 ′. Here, since the direction of the opening valve 118 is adjusted to the enlarged blade 3 in the protruding state, the action of cleaning the enlarged blade 3 used for building the enlarged bulb portion 82 when the cement milk is discharged also works. Therefore, even if excavated soil or the like is stuck to the enlarged blade 3, it is washed away,
The enlarged blade 3 can be easily stored in the excavating blade 12. If it is notified on the ground display panel that the upper and lower bits 1a and 1b are rotating together, the same operation as in the first embodiment is performed.

(3) Effects of the Embodiment When the embedding pile construction was performed using the enlarged excavation apparatus according to the first embodiment, the enlarged blade 3 can be reliably projected and retracted by the link mechanism 4, and the desired enlargement can be achieved. Bulb part 8
2 could be formed. Furthermore, since it was seen from the display panel on the ground whether the enlarged blade 3 was in the protruding state or the retracted state, such a confirming method was established, and it was found that the construction was appropriate in the vertical inspection. . In addition, the microswitches 551 and 561 catch the position information of the enlarged blade 3 and transmit it to the ground. However, since the inside of the hollow portion such as the cylindrical shaft 11 and the screw rod 9 into which the consolidation liquid is injected is used, a barrier is formed. It did not exist and could be performed within the range of weak radio waves without being restricted by the Radio Control Law.

In the second and third embodiments, the enlarging auxiliary blade 121 is used.
According to the enlarged excavation device provided with, it is not necessary to excavate while breaking the earth wall with the friction cutter 83, and in the process of proceeding with the conventional excavation method, the excavation auxiliary blade 121 cuts out an excavation area of about a pile diameter. I was able to. Since the load applied to the enlarged blade is reduced without depending on the excavation of all the enlarged bulb portions 82 on the enlarged blade 3, the screw rod 9
The rotation drive source can be made smaller, and the construction can be carried out smoothly.

In the third embodiment, the bolts 113, which are components, are eliminated while securing the effects of the first and second embodiments. Therefore, once assembled, the first and second embodiments are extremely difficult to disassemble.
Assembly and disassembly became easier compared to 2. The components such as the protruding piece 41 and the stop piece 56 are no longer required, so that the structure is simplified. Therefore, a small pile (for example, 500 mm
It is possible to manufacture the enlarged excavator A up to about φ), and the application range of the embedded pile method using the apparatus of the present invention is expanded. Further, after forming the enlarged bulb portion 82, when the lower bit 1b is rotated counterclockwise to close the enlarged blade 3, an aqueous solution of cement milk or the like blows off the attached debris attached to the enlarged blade 3 from the opening valve 118 in advance. It is easy to close.

The present invention is not limited to the specific embodiments described above, but can be variously modified within the scope of the present invention depending on the purpose and application. For example, the enlarged excavator of the present invention may be used for a pre-boring tip enlarged root compaction method. The number of the expanding blades 3 is not limited to the embodiment.

In the first embodiment, the cylindrical shaft 11 of the upper bit 1a is
The stopper 5 provided on the lower bit 1b
5, but instead of this, a projecting piece 41 formed on the cylindrical shaft 11 of the lower bit 1b is attached to the upper bit 1
The stopper 55 provided at the position a may be locked.
In the third embodiment, the connection joint 6 is connected to the upper bit 1a.
, And the guide shaft 7 is loosely inserted into the elongated hole 115 formed on the side surface of the cylindrical shaft 11 of the lower bit 1b, and the guide shaft 7 is screwed into the connection joint 6, so that the elongated hole 115 is formed. Is designed to limit the rotation range of the connection joint 6, but instead of this, the connection joint 6 is fixed to the lower bit 1b, and an elongated hole 115 is formed in the side surface of the cylindrical shaft 11 in the upper bit 1a. The guide shaft 7 is loosely inserted into the elongated hole 115 and the guide shaft 7 is screwed into the connection joint 6.
May be limited.

In this embodiment, the expanding blade 3 is provided with the lower bit 1b.
It is attached to. This is because the enlarged bulb portion 82 can be built up to the vicinity of the shaved bottom. However, if the enlarged bulb portion 82 is higher than the height of the lower bit 1b,
a. This is because the enlarged bulb portion 82 is not formed in the vicinity of the shaved bottom, and the effect of expressing the tip supporting force is reduced, but the effect is reduced.

The micro switches 551 and 561
Can use a magnetic force and the like in addition to the limit method. The mounting position of the micro switches 551 and 561 is
5, not only the stop piece 56 but also any place of the upper and lower bits 1a and 1b, the hollow joint 2 and the ring mechanism 4, and it is sufficient that the protrusion 41 works only when the stop piece 56 is locked. . Similarly, the mounting position of the microswitches 116 and 117 is not limited to the cylindrical shaft 11, but may be any of the upper and lower bits 1a and 1b, the connection joint 6, the guide shaft 7, and the ring mechanism 4 '.

Transmission to the display panel on the ground is not limited to radio waves, but wireless using infrared rays or the like, or wiring may be laid. The display on the operation panel of the ground operator includes not only a visual display but also an auditory display.

[0050]

As described above, when the enlarged excavator of the present invention is used, when the bulb portion is formed at the tip of the pile, the enlarged blade is reliably projected, and after the enlarged bulb portion is formed, the enlarged blade is returned to its original shape. Not only is it a mechanism that can reliably retract to the state,
Since a system that can confirm this from the ground has been established, it has a great effect on improving work efficiency and improving the quality of construction management.

[Brief description of the drawings]

FIG. 1 is a front view of an enlarged excavator according to a first embodiment.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is an explanatory cross-sectional view showing a state where an enlarged blade is projected in FIG. 2;

FIG. 4 is an enlarged view around the link mechanism of FIG. 1;

FIG. 5 is an enlarged perspective view of a hollow joint according to the first embodiment.

FIG. 6 is an enlarged view showing an attached state of upper and lower bits and a stopper in the first embodiment.

FIG. 7 is an explanatory view showing a state in which the excavation device of the first embodiment excavates to a shaved bottom with a drill bit.

FIG. 8 is an explanatory view showing a state in which the excavation blade pierces a new tip ground in the first embodiment.

FIG. 9 is an explanatory view of a state of the enlarged excavator in which the enlarged blade is projected in the first embodiment.

FIG. 10 is a front view of an enlarged excavator according to a second embodiment.

FIG. 11 is an explanatory view showing a state in which an excavation bit is excavated to a shaved bottom with an enlarged excavator according to a second embodiment.

FIG. 12 is a front view of an enlarged excavator according to a third embodiment.

FIG. 13 is an enlarged view around the link mechanism of FIG. 12;

FIG. 14 is an exploded front view around a connection joint according to a third embodiment.

FIG. 15 is an exploded plan view around a connection joint according to a third embodiment.

FIG. 16 is a sectional view taken along line YY of FIG. 12;

FIG. 17 is an explanatory sectional view showing a state in which the enlarged blade is projected in FIG. 16;

FIG. 18 is an explanatory diagram showing a state where a drill bit is used to excavate to a shaved bottom by the enlarged excavator of the third embodiment.

FIG. 19 is an explanatory diagram of the state of the enlarged excavator in which the enlarged blade is projected in the first embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drilling bit 11 Cylindrical shaft 115 Slot 116 Micro switch 117 Micro switch 12 Drilling blade 121 Expansion auxiliary blade 122 Support shaft 13 Drilling blade 1a Upper bit 1b Lower bit 2 Hollow joint 3 Expansion blade 31 Bracket 32 Support shaft 4 Link mechanism 4 ' Link mechanism 41 Projection piece 55 Stopper 551 Micro switch 55 Stopper 56 Stop piece 561 Micro switch 57 Stop piece 6 Connection joint 7 Guide shaft 9 Screw rod A Enlarged excavator

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) E21B 10/44 E21B 7/28

Claims (2)

(57) [Claims] An upper and lower bit (1a), (1b) provided with a drilling blade around a cylindrical axis and divided into two so as to cross a drilling bit (1) having a drilling blade formed at a lower end of the drilling blade.
And a connection joint (6) for rotatably joining the upper bit and the lower bit to each other, and loosely inserted into an elongated hole formed on the side surface of the cylindrical shaft of the upper bit or the lower bit to be fixed to the connection joint, and A guide shaft (7) for restricting a rotation range of the connection joint by a hole, an enlarged blade (3) rotatably mounted on a support shaft provided on a bracket of the upper bit or the lower bit, and an upper bit of the upper bit. A link mechanism (4 ') for connecting the guide shaft and the enlargement blade so that the enlargement blade swings by rotation; when the upper bit rotates forward, the guide shaft is locked at one end of the elongated hole; By this, the upper and lower bits retain the shape of the excavating blade before splitting, while the link mechanism forcibly stores the enlarged blade in the excavating blade, while the upper bit reversely rotates, the enlarged blade Protruding outward, protruding Larger rigs which the guide shaft to retain was state is characterized by being configured as locked at the other end of the elongated hole. 2. A those described in claim 1, the upper and lower bits, connection joints, guide shaft, a micro switch is provided on at least one of the link mechanism, at one end of the guide shaft long hole by the forward rotation of the upper bits An enlarged excavator, characterized in that the microswitch is actuated at the time of locking to transmit the completion of the extension blade extension to the ground via the cylindrical shaft and the hollow portion of the screw rod.