JP2023041363A - Boring and agitating machine - Google Patents

Abstract

To provide a boring and agitating machine allowing vertical vibration and turning force in clockwise/counterclockwise directions around a rod shaft to be transmitted to an excavation head arranged on a tip of a rod, the vertical vibration and turning force being applied on the rod.SOLUTION: A boring and agitating machine is to bore the ground with a boring head by applying turning force and vertical vibration on a rod on which tip the boring head is connected, wherein the rod comprises a rod body and a joint structure connecting the rod body in an axial direction, and the joint structure comprises: a convex joint, on which outer circumferential surface a flange is arranged, and which is provided with a square cylindrical part; a concave joint on which outer circumferential surface a flange is arranged, and which is provided with a square hole part fitted in the square cylindrical part; and a pressing member clamping the flange of the convex joint and the flange of the concave joint by making them abut on each other. An abutment cross section of the flange of the convex joint and the flange of the concave joint has a tapered shape narrowing toward an outer circumferential edge.SELECTED DRAWING: Figure 6

Description

The present invention relates to a drilling agitator for drilling ground.

For example, Patent Literature 1 discloses a drilling and stirring device used when constructing a soil cement column in the ground. The drilling stirrer includes a rod having a drilling bit connected to the tip thereof, and while the rod is rotated around its axis by a rotating means, a vertical vibration is imparted to the rod via a vibrating means to excavate. Drill a hole in the ground with a bit. In addition, a soil cement column is constructed in the drilled hole by discharging cement milk from the tip of the drilling bit while drilling the ground.

In the drilling and agitating device of Patent Document 1 described above, the rod has a shape in which a plurality of steel pipes are connected in series by a screw joint structure. For this reason, the operation of the rotating means for rotating the rod around the axis is controlled so that it rotates only in the same direction as the tightening direction in the threaded joint structure.

JP 2011-252349 A

According to the drilling stirrer of Patent Document 1, since the drilling bit rotates and vibrates vertically through the rod, the drilling bit can be efficiently drilled even if there is a hard layer in the ground, and the soil cement column can be constructed. be able to. However, as described above, the direction of rotation of the rod with the drilling bit is limited to one direction around the axis. For this reason, for example, if there is a gravel layer or a backfill layer that is compacted with slag, etc. in the ground, and the drilling bit spins or bites into these layers during excavation, it becomes impossible to excavate. It is not possible to take countermeasures such as temporarily reversing the direction of rotation.

Therefore, after once raising the drilling bit together with the rod, the position of the drilling bit is moved by rotating it appropriately, and then it descends, and after reaching the bottom of the drilling, drilling is restarted. There was no choice but to deal with it, and the construction operation was complicated.

In addition, when vertical vibration is applied to the rod via the vibrating means, the screw joint structure is likely to loosen and rattle. When such rattling occurs, even if vertical vibration is applied to the rod, it cannot be smoothly transmitted to the drilling bit, and it may not be possible to expect an improvement in drilling efficiency due to the application of the vibration.

The joint structure used to connect the rods is not limited to the screw type joint structure of Patent Document 1. For example, a flange type joint structure as shown in FIG. Adoption of such a hexagonal joint pin type joint structure is also conceivable.

A flange type joint structure 70 shown in FIG. Such a flange type joint structure 70 transmits vertical vibrations applied to the upper steel pipe 31b and rotational force about the steel pipe axis to the lower steel pipe 31b via the bolts 73 . Therefore, if there is a hard layer in the ground, the number of bolts 73 must be increased, which takes a long time for connection work. Also, if the above-mentioned vertical vibration or rotational force around the steel pipe axis is repeatedly applied to the bolt joint, loosening is likely to occur. .

The hexagonal joint pin type joint structure 80 shown in FIG. A pair of connection pins 81 are passed through these. The pair of connection pins 81 are displaced in the height direction on both sides of the axis of the male joint 82 and the female joint 83 and are penetrated in the direction orthogonal to the axis. For this reason, the square hole portion 831 is provided with a through hole 832 through which the connection pin 81 passes, and the square cylinder portion 821 is provided with a notch 822 through which the connection pin 81 passes.

In such a hexagonal joint pin type joint structure 80, the connecting pin 81 cannot be inserted if there is no play between the connecting pin 81 and the square hole portion 831 and square tube portion 821 in the fitted state. Then, even if vertical vibration is applied to the steel pipe 31b on the upper side, there is a possibility that this vibration cannot be transmitted to the steel pipe 31a on the lower side due to play. Instead of providing play, for example, it is conceivable to provide the connection pin 81 with a taper to form a wedge shape.

The present invention has been made in view of such problems, and its main object is to provide a drilling head provided at the tip of the rod with which the vertical vibration applied to the rod and the rotating force in the forward and reverse directions about the rod axis are applied to the drilling head. To provide a drilling stirrer capable of transmitting to

In order to achieve such an object, the drilling agitator of the present invention is a drilling agitator that excavates the ground with the drilling head by applying rotational force and vertical vibration to a rod having a drilling head connected to its tip. wherein the rod has a rod body and a joint structure that connects the rod body in the axial direction, and the joint structure is provided with a flange on an outer peripheral surface and a convex joint having a rectangular tubular portion. , a concave joint provided with a flange on the outer peripheral surface and having a square hole portion that fits with the square tube portion, and a pressing member that abuts and holds the flange of the convex joint and the flange of the concave joint. A cross-section obtained by abutting the flange of the convex joint and the flange of the concave joint is tapered toward the outer peripheral edge.

According to the drilling stirrer of the present invention described above, the rod having the drilling head connected to the tip thereof has a joint structure that connects a plurality of rod bodies, and the convex joint that constitutes the joint structure is a square tube. and the concave joint has a square hole into which the square tubular portion is fitted. As a result, through the square hole portion of the concave joint and the square tube portion of the convex joint, which constitute the joint structure, the forward and reverse rotational forces applied to one of the rod bodies connected by the joint structure can be transmitted to the other. .

In addition, a cross-section obtained by abutting the flange of the convex joint and the flange of the concave joint sandwiched by the pressing members forms a taper that tapers toward the outer peripheral edge. Therefore, if the holding member is provided with a fitting groove that engages with this taper, the flange of the convex joint and the flange of the concave joint enter into the fitting groove in a wedge-like manner. The tightening force in the axial direction) is increased, and the convex joint and the concave joint can be firmly clamped. As a result, vertical vibration applied to one of the rod bodies connected by the joint structure can be transmitted to the other via the pressing member that constitutes the joint structure.

Therefore, the excavation head provided at the tip of the rod is provided with vertical vibration and rotational force in the forward and reverse directions about the rod axis, which are applied to the base end of the rod formed by connecting a plurality of rod bodies with a joint structure. can be given to In this way, when there is a gravel layer with compacted gravel in the ground, for example, even if the drilling head spins or bites into the gravel layer and becomes unable to drill, the drilling head can be reversed via the rod. Countermeasures such as rotating can be taken. As a result, even if there is a gravel layer in the ground, the excavation work can be continued without complicated operations, and the workability of ground excavation can be greatly improved.

According to the present invention, a plurality of rod bodies constituting a rod having a drilling head provided at its tip are sandwiched between a convex joint having a square tubular portion and a concave joint having a square hole into which the square tubular portion is fitted. The vertical vibration imparted to the rod and the rotating force in forward and reverse directions around the rod axis are smoothly transmitted to the drilling head provided at the tip of the rod. becomes possible.

It is a figure which shows the drilling stirrer in embodiment of this invention. It is a figure which shows the rod main body in embodiment of this invention. It is a figure which shows the square tube part of a convex joint in embodiment of this invention, and the square hole part of a concave joint. It is a figure which shows the procedure which forms the joint structure in embodiment of this invention (the 1). It is a figure which shows the procedure which forms the joint structure in embodiment of this invention (2). It is a figure which shows the detail of joint structure in embodiment of this invention. It is a figure which shows the procedure which replenishes the rod main body and extends|stretches a rod in embodiment of this invention (the 1). It is a figure which shows the procedure which replenishes the rod main body and extends|stretches a rod in embodiment of this invention (the 2). It is a figure which shows a mode that a gravel layer is excavated by the excavation stirrer in embodiment of this invention. It is a figure which shows the joint structure (flange type and a hexagon joint pin type) of a prior art.

The drilling stirrer of the present invention will be described in detail with reference to FIGS. 1 to 9. FIG. In the present embodiment, the case of constructing an underground hole is taken as an example, but the drilling agitator can also be used to construct a soil cement column.

≪≪Drilling Mixer≫≫
As shown in FIG. 1, a drilling stirrer 1 used when excavating a target ground is supported by a crawler traveling body 2 and an upper revolving body 3 mounted on the crawler traveling body 2 so that it can be raised and lowered. and a reader 4.

The leader 4 is provided with a guide 41 extending vertically on the front side thereof in a standing posture, and an elevating body 42 that moves up and down along the guide 41 is attached. Two telescoping devices 43 and 44 are provided on the back side, and the leader 4 and the upper rotating body 3 are connected through these. The leader 4 can be freely raised and lowered by the expansion and contraction operations of the expansion and contraction devices 43 and 44 .

The reader 4 also has a chuck mechanism 45 at its lower end. Any device may be adopted as the chuck mechanism 45 as long as it has a configuration capable of gripping the rod 20 and the excavation head 10, which will be described later. Moreover, the chuck mechanism 45 does not necessarily have to be attached to the leader 4, and a separate device from the drilling stirrer 1 may be employed.

The drilling stirrer 1 further includes a vibrating device 9 mounted on an elevating body 42, a rotating device 8 connected to the lower portion of the vibrating device 9, and a base end extending through the rotating device 8. , a rod 20 connected to the tip of the drive shaft 7 , and a drilling head 10 connected to the tip of the rod 20 .

The vibratory device 9 is a device that generates a vertical vibratory force by rotating an eccentric weight. It will be a mode to move to. Any device may be adopted as the vibration generator 9 as long as it can generate a vibration generator capable of transmitting vibration including a component in the vertical direction to the drive shaft 7 .

The rotating device 8 is installed on the lifting body 42 and connected to the vibrating device 9 , and moves along with the vibrating device 9 along the leader 4 in the standing posture. A drive shaft locking portion (not shown) is provided inside the drive shaft 7 to lock the peripheral surface of the drive shaft 7 and apply rotational force in the forward or reverse direction around the shaft.

The drive shaft 7 consists of a single tube having a hollow portion, and a swivel joint 6 is mounted in the middle thereof to which a fluid supply pipe 5 such as a cement milk supply pipe or a stabilizer supply pipe is connected. As a result, it becomes possible to supply the fluid such as cement milk or the stabilizing liquid S supplied from the fluid supply pipe 5 to the rod 20 from the swivel joint 6 via the drive shaft 7 . In FIG. 1, the case where the stabilizing liquid S is supplied is taken as an example.

The rod 20 is composed of a rod body 30 and a joint structure 50 that axially connects the rod body 30 . Its proximal end is connected to the drive shaft 7 via a joint structure 50 and its distal end is connected to the drilling head 10 via a joint structure 50 . Details of the rod body 30 and the joint structure 50 will be described later.

The excavation head 10 is connected to a rod 20 and includes a shaft portion 11 made of a single tube having a hollow portion, an excavation wing body 13 attached near the tip of the shaft portion 11 so as to extend sideways, and an excavation head. and a bit 14 attached to the wing body 13 . A plurality of radially extending stirring blades 12 are installed on the shaft portion 11 at a position spaced apart from the excavation blade main body 13 . is provided.

The bit 14 and the tip bit 15 are shaped so that the ground can be excavated when the excavating head 10 rotates about the rod axis in either the forward direction or the reverse direction. Further, the fluid discharge port 16 discharges the fluid supplied to the shaft portion 11 from the fluid supply pipe 5 via the swivel joint 6, the drive shaft 7 and the rod 20 toward the ground. In this embodiment, since the underground hole H is excavated, the fluid discharged from the fluid supply pipe 5 is the stable liquid S. It is also possible to construct soil cement columns.

Further, the agitating blade 12 provided in the excavating head 10 is used when agitating while excavating the ground while discharging cement milk from the fluid discharge port 16 when constructing the soil cement column as described above, or when agitating the cement milk while excavating the ground, is constructed, a cement-based solidifying material is supplied to the underground hole H and stirred with the stabilizing liquid.

≪≪Rod Details≫≫
In the drilling stirrer 1 having the configuration described above, the rod 20 is vibrated in the vertical direction by the vibrating device 9 via the drive shaft 7 and in the forward and reverse directions around the rod axis by the rotating device 8. It has a configuration capable of transmitting directional rotation to the drilling head 10 . Details of the rod body 30 and the joint structure 50 that constitute the rod 20 will be described below. Since the joint structure 50 is also employed to connect the drive shaft 7 and the drilling head 10 to the rod 20, these will also be described.

≪≪Rod Body≫≫
As shown in FIG. 2, the rod body 30 includes a pipe member 31 and convex joints 32 and concave joints 33 at both ends thereof.

The tube member 31 is made of a single tube similar to the drive shaft 7 and the shaft portion 11 of the drilling head 10 described above, and has a hollow portion 311 through which the fluid supplied from the fluid supply pipe 5 flows down. A convex joint 32 is connected to one end thereof, and a concave joint 33 is connected to the other end thereof. FIG. 2 illustrates a state in which the pipe member 31 is erected with the convex joint 32 facing upward.

The convex joint 32 is composed of a cylindrical body provided with a hollow portion 321 that communicates with the hollow portion 311 of the pipe member 31 , and the base end side is formed into a cylindrical portion 322 having the same size and shape as the pipe member 31 in cross section. It is fixed to the pipe material 31 by fixing means such as welding. On the other hand, the distal end side has a cross section smaller than that of the tubular member 31, and forms a rectangular cylindrical portion 323 formed in a hexagonal doughnut shape as shown in FIG. 3(a).

A convex flange 324 is provided near the boundary between the cylindrical portion 322 on the base end side and the rectangular tube portion 323 on the distal end side. The convex side flange 324 is formed so as to protrude from the outer peripheral surface of the cylindrical portion 322, and is formed in a truncated cone shape having a lower bottom surface on the rectangular tube portion 323 side and a side surface on the cylindrical portion 322 side. As shown in FIG. 6, the rectangular tubular portion 323 side serves as a facing surface 324a with a concave side flange 334 described later, and the cylindrical portion 322 side serves as a contact surface 324b with the pressing member 40 described later.

As shown in FIG. 2, the concave joint 33 is formed in a housing cylinder portion 332 whose cross section has the same size and shape as the pipe member 31 over the entire length, and communicates with the hollow portion 311 of the pipe member 31 on the base end side. A hollow portion 331 is provided. On the other hand, a square hole portion 333 is formed on the distal end side to fit the square tubular portion 323 of the convex joint 32, and the square hole portion 333 and the hollow portion 331 communicate with each other. The inner peripheral section of the square hole portion 333 is formed into a hexagon having the same size as the outer peripheral surface of the square tube portion 323, as shown in FIG. 3(b).

A recessed side flange 334 is provided at the tip of the housing tube portion 332 . The concave side flange 334 is formed so as to protrude from the outer peripheral surface of the storage tube portion 332, and is formed in a truncated cone shape with the tip side as the lower bottom surface and the tube material 31 side as the side surface. As shown in FIG. 6, the distal end side serves as a facing surface 334a with the convex side flange 324 described above, and the tube member 31 side serves as a contact surface 334b with the pressing member 40 described later.

<<<Joint structure 50>>>>
As shown in FIG. 1, a plurality of rod bodies 30 having the above configuration are arranged in parallel in the axial direction, and between adjacent rod bodies 30, a convex joint 32 and a concave joint 33 provided in the rod body 30, A joint structure 50 configured with the pressing member 40 is formed to form the rod 20 .

That is, as shown in FIGS. 4(a) and 4(b), the square tubular portion 323 constituting the convex joint 32 of the rod body 30a located on the lower side constitutes the concave joint 33 of the rod body 30b located on the upper side. It is inserted into the square hole portion 333 and fitted, and the facing surface 324a of the convex side flange 324 and the facing surface 334a of the concave side flange 334 are brought into contact. As a result, forward and reverse rotational forces applied to the upper rod body 30b are transferred to the lower rod body 30a through the square hole portion 333 of the concave joint 33 and the square tubular portion 323 of the convex joint 32. It becomes possible to transmit

At this time, the rod packing 60 is interposed between the tip of the square tubular portion 323 of the convex joint 32 and the square hole portion 333 of the concave joint 33 . The rod packing 60 is formed in a ring shape with a hole in the center so as to maintain communication between the hollow portions 321 and 331 of the convex joint 32 and the concave joint 33 .

In this way, the convex side flange 324 and the concave side flange 334 with the facing surfaces 324a and 334a butted against each other are sandwiched by the pressing member 40 as shown in FIGS. 5(a) and 5(b). As a result, vertical vibration applied to the upper rod body 30b can be transmitted to the lower rod body 30a via the pressing member 40. As shown in FIG.

<<Pressing member 40>>
As shown in FIGS. 5(a) and 5(b), the pressing member 40 that constitutes the joint structure 50 described above includes half members 401 and 402 and a fastener 403. The fastener 403 includes bolts 403a and bolts 403a. A nut 403b is provided.

As shown in FIG. 5A, the half members 401 and 402 are ring-shaped members having a size capable of surrounding the convex side flange 324 of the convex joint 32 and the concave side flange 334 of the concave joint 33. Radially projecting ear portions 401b are provided at both ends of the half member 401 in the circumferential direction. These ear portions 401b are formed with bolt holes through which bolts 403a pass. Similarly, the half-split member 402 is provided with ear portions 402b at both ends in the circumferential direction, and bolt holes through which bolts 403a pass are formed.

A fitting groove 401a continuous in the circumferential direction is formed in the inner peripheral surface of the half-split member 401 . As shown in FIG. 6, the cross-sectional shape is formed so as to fit with the convex side flange 324 and the concave side flange 334 when the opposing surfaces 324a and 334a are abutted against each other. Since the cross section where the convex side flange 324 and the concave side flange 334 are butted against each other forms a taper that tapers toward the outer peripheral edge, the fitting groove 401a is a substantially V-shaped tapered groove that can be fitted with this taper. formed. A fitting groove 402a continuous in the circumferential direction is also formed in the half member 402, and a substantially V-shaped tapered groove similar to the fitting groove 401a is formed.

The mounting procedure of the pressing member 40 having the above configuration is as follows. As shown in FIG. 5(a), the half members 401 and 402 are arranged so as to surround the convex side flange 324 and the concave side flange 334 in the butted state, and these are fitted into the fitting grooves 401a and 402a. insert into and mate. As a result, the ear portions 401b and 402b of the half members 401 and 402 face each other, so that the bolt 403a is inserted through the bolt holes formed in the ear portions 401b and 402b as shown in FIG. , the nut 403b is screwed and tightened.

Then, as shown in FIG. 6, as the half members 401 and 402 gradually approach each other, the convex side flange 324 and the concave side flange 334 enter into the fitting grooves 401a and 402a in a wedge shape. At this time, both the fitting grooves 401a and 402a have a groove depth D such that the outer peripheral end faces of the convex side flange 324 and the concave side flange 334 do not come into contact with the groove bottom. As a result, the convex side flange 324 and the concave side flange 334 are sufficiently penetrated into the fitting grooves 401a and 402a, so that the tightening force in the vertical direction (the axial direction of the convex joint 32 and the concave joint 33) increases. and the concave joint 33 can be held firmly.

Therefore, even when vertical vibration is transmitted from the concave joint 33 side, it is possible to transmit the vertical vibration to the convex joint 32 side via the pressing member 40 without causing rattling. The tightening effect of the pressing member 40 on the convex side flange 324 and the concave side flange 334 can be obtained by setting the taper angle θ of the cross section where the convex side flange 324 and the concave side flange 334 are butted to about 10 to 60°. It is preferably about 26°, more preferably about 26°.

The pressing member 40 may be provided with an eyebolt E as shown in FIG. 6, for example. In this way, when the pressing member 40 is attached and detached, the eyebolt E can be used to suspend the pressing member 40 with a wire, thereby preventing a fall of the pressing member 40 .

The joint structure 50 described above is also employed for connecting the rod 20 and the drive shaft 7 and for connecting the rod 20 and the excavating head 10, as shown in FIG. In FIG. 1, the concave joint 33 is arranged on the lower end side of the rod body 30 in the upright state, and the convex joint 32 is arranged on the upper end side. Therefore, following this, a convex joint 32 is installed at the upper end of the drilling head 10 and a concave joint 33 is installed at the lower end of the drive shaft 7 .

Further, when constructing a long underground hole H, the joint structure 50 can be used to easily extend the rod body 30 and extend the rod 20, and the extended rod 20 can be connected to the drive shaft 7. be able to. A procedure for extending the rod 20 by adding a new rod main body 30c will be described below.

≪Procedure for adding the rod body≫
As shown in FIG. 7( a ), the positive rotational force of the rotating device 8 and the vertical vibration of the vibrating device 9 are transmitted from the drive shaft 7 to the excavating head 10 via the rod 20 to move the ground. Excavate and construct a hole H. Before starting underground drilling, the following preparatory works are being carried out.

The drilling stirrer 1 is installed so that the leader 4 with the guide 41 arranged in an upright posture is arranged at a predetermined position via the extension devices 43 and 44 . Next, the planned excavation position is preliminarily excavated, the excavation head 10 is inserted, and the rod body 30 is connected to the shaft portion 11 and the drive shaft 7 of the excavation head 10 . All of these are connected by providing the joint structure 50 as described above.

Specifically, as shown in FIG. 1, by fitting the convex joint 32 of the shaft portion 11 and the concave joint 33 of the rod body 30 together, and attaching the holding member 40 to them to provide the joint structure 50, The shaft portion 11 and the rod body 30 are connected. Similarly, the rod main body 30 and the drive shaft 7 are connected by fitting the convex joint 32 of the rod body 30 and the concave joint 33 of the drive shaft 7, and attaching the pressing member 40 to them to provide the joint structure 50. .

Further, during construction, as shown in FIG. 7A, the stabilizing liquid S is supplied from the fluid supply pipe to the drive shaft 7 via the swivel joint, and passed through the rod 20 and the shaft portion 11 of the drilling head 10. , to the underground hole H from the fluid outlet 16 . The stable liquid S filling the underground hole H is discharged using a vacuum hose V inserted into the hole. As shown in FIG. 7B, as the excavation progresses, the excavation head 10 descends, and when the joint structure 50 formed on the rod 20 approaches the vicinity of the upper end of the chuck mechanism 45, the rotating device 8 and the vibrating device 9 are moved. to stop.

The pressing member 40 is removed from the joint structure 50 that connects the rod body 30 and the drive shaft 7 while the chuck mechanism 45 grips the rod body 30 that constitutes the rod 20 . When the pressing member 40 is removed, as shown in FIG. 7C, the lifting body 42 on which the rotating device 8 and the vibrating device 9 are installed is raised along the guide 41 . In this way, the convex joint 32 provided at the upper end of the rod body 30 is exposed, and the concave joint 33 provided at the lower end of the drive shaft 7 is exposed. A work space is provided between the concave joint 33 of the drive shaft 7 and the convex joint 32 of the rod body 30 for adding a new rod body 30c.

Using this working space, a new rod body 30c is connected to the drive shaft 7 and the rod body 30 gripped by the chuck mechanism 45, as shown in FIG. 8(a). Specifically, as shown in FIG. 8(b), the convex joint 32 of the rod body 30 gripped by the chuck mechanism 45 and the concave joint 33 of the new rod body 30c are fitted, and the holding member 40 is fitted to these joints. to provide the joint structure 50 . As a result, a new rod body 30c is added, and the member length of the rod 20 is extended.

After that, while appropriately adjusting the height position of the drive shaft 7 using the elevating body 42, the convex joint 32 of the new rod body 30c and the concave joint 33 of the drive shaft 7 are fitted, and the holding member is attached to them. 40 is installed to provide a joint structure 50 . As a result, the rod 20 with the extended member length hangs down from the drive shaft 7, so that the chuck mechanism 45 is opened and the rotating device 8 and the vibrating device 9 are operated as shown in FIG. 9(c). and restart the construction work of the underground hole H.

In such a procedure, the rod 20 to which the rod body 30 has been added via the joint structure 50 is subjected to positive rotational force by the rotating device 8 and vertical direction by the vibration generating device 9, which are imparted via the drive shaft 7. is smoothly transmitted to the drilling head 10 connected to the tip side of the rod 20. Therefore, even if a hard layer exists in the ground during excavation, it can be crushed by impact with the bit 14 and the tip bit 15 of the excavation head 10 to which vertical vibration is transmitted, or large gravel can be moved by vibration. , it is possible to continue drilling.

Also, the joint structure 50 employs the pressing member 40 and does not use a pair of connection pins 81 unlike the hexagonal joint pin type joint structure 80 of FIG. Therefore, it is possible to shorten the fitting range of the convex joint 32 and the concave joint 33 . That is, when a pair of connection pins 81 are employed, as shown in FIG. Notches 822 through which 81 passes need to be provided at different positions in the height direction. However, since the square hole portion 333 and the square tube portion 323 of the joint structure 50 can be omitted, the height can be set low, and the fitting range is also small.

As a result, without changing the overall length of the rod body 30, the member length of the pipe material 31 can be lengthened by the shortened fitting range of the convex joint 32 and the concave joint 33. Even if the area is in a low-head space and there is a limit to securing the working space for adding the rod bodies 30, it is possible to reduce the number of the rod bodies 30 that are added to extend the rods 20. . Along with this, the number of times of work for adding the rod body 30 can be reduced, so that the work efficiency when constructing the underground hole H is greatly improved, and it is possible to contribute to shortening the construction period.

Furthermore, when a gravel layer G in which gravel is compacted as shown in FIG. In some cases, the gravel bites into the gravel layer G, or the separated gravel enters between the gravel layer G and the excavation head 10, causing the excavation head 10 to idle, making excavation impossible. In such a case, as shown in FIG. 9B, countermeasures can be taken such as applying a rotating force in the opposite direction around the axis to the rod 20 by the rotating device 8 .

As a result, even if there is a gravel layer G in the ground, the excavation work can be continued without complicated operations, and the workability of the underground excavation can be significantly improved. At this time, since the excavating head 10 has a structure capable of excavating in both forward and reverse rotation, excavation may proceed while rotating in the reverse direction, or may be switched to forward rotation to restart the excavation work. You may

The drilling agitator of the present invention is not limited to the above embodiment, and various modifications are possible without departing from the scope of the present invention.

For example, in the present embodiment, as shown in FIG. 4, the rectangular tube portion 323 of the convex joint 32 and the rectangular hole portion 333 of the concave joint 33 are formed in a hexagonal shape, but the shape is not necessarily limited to this. Any shape such as a triangular shape or a square shape may be adopted as long as the convex joint 32 and the concave joint 33 do not mutually rotate about the axis.

Further, in the present embodiment, the convex joint 32 is arranged at the upper end and the concave joint 33 is arranged at the lower end of the rod body 30 in the upright posture, but the present invention is not limited to this. Alternatively, the rod body 30 having the convex joints 32 arranged at the top and bottom and the rod body 30 having the concave joints 33 arranged at the top and bottom are prepared, and the combination of both is connected by the joint structure 50 to form the rod 20. You may

Furthermore, in this embodiment, as shown in FIG. 5A, the pressing member 40 is composed of half members 401 and 402 and a fastener 403, and the fastener 403 has a total of four bolts 403a and nuts 403b. was adopted, but any quantity is acceptable. Further, as shown in FIG. 6, if it is possible to apply a tightening force in the vertical direction to the convex side flange 324 and the concave side flange 334, the fastener 403 is limited to a combination of a bolt 403a and a nut 403b. not something to do.

In addition, the half-split members 401 and 402 may not necessarily be separate members. It may be structured to be tightened with

1 drilling stirrer 2 crawler traveling body 3 upper revolving body 4 leader 41 guide 42 lifting body 43 expansion device 44 expansion device 45 chuck mechanism 5 fluid supply pipe 6 swivel joint 7 drive shaft 8 rotating device 9 vibrating device 10 drilling head 11 Shaft 12 Stirring blade 13 Excavation blade body 14 Bit 15 Tip bit 16 Fluid discharge port 20 Rod 30 Rod body 30a Rod body (lower side)
30b Rod body (upper side)
30c New rod body 31 Pipe member 31a Steel pipe (lower side)
31b Steel pipe (upper side)
32 Convex joint 321 Hollow part 322 Cylindrical part 323 Rectangular tube part 324 Convex flange 324a Opposing surface 324b Contact surface 33 Concave joint 331 Hollow part 332 Storage cylinder 333 Square hole 334 Concave flange 334a Opposing surface 334b Contact surface 40 Holding member 401 Half member 401a Fitting groove 401b Ear 402 Half member 402a Fitting groove 402b Ear 403 Fastener 403a Bolt 403b Nut 50 Joint structure 60 Rod packing 70 Joint structure (flange type)
71 Flange 72 Flange 73 Bolt 80 Joint structure (hexagonal joint pin type)
81 Connection pin 82 Male joint 821 Square cylinder 822 Notch 83 Female joint 831 Square hole G Gravel layer H Underground hole V Vacuum hose E Eyebolt S Stabilizing liquid

Claims (1)

A drilling stirrer that drills the ground with the drilling head by applying rotational force and vertical vibration to a rod having a drilling head connected to the tip,
The rod has a rod body and a joint structure that connects the rod body in the axial direction,
The joint structure is
A convex joint provided with a flange on the outer peripheral surface and having a rectangular tubular portion;
a concave joint provided with a flange on the outer peripheral surface and having a square hole portion that fits with the square tube portion;
A pressing member that abuts and sandwiches the flange of the convex joint and the flange of the concave joint,
A drilling agitator characterized in that a cross-section obtained by abutting the flange of the convex joint and the flange of the concave joint forms a taper that tapers toward an outer peripheral edge.

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