Hole-cutting stirrer

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

Technical Field

[0001] The present invention relates to a drilling and stirring machine for excavating the ground.

Background Art

[0002] For example, Patent Document 1 discloses a drilling and stirring device used when constructing soil-cement columns in the ground. The drilling and stirring device includes a rod having a drilling bit connected to its tip, and by rotating the rod around its axis by a rotating means and applying a vertical vibration to the rod via an oscillating means, the ground is drilled with the drilling bit. Further, while drilling the ground, a soil-cement column is constructed in the drilled hole by discharging cement milk from the tip of the drilling bit.

[0003] In the drilling and stirring 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-type joint structure. Therefore, the operation of the rotating means for rotating the rod around its axis is controlled so as to rotate only in the same direction as the tightening direction in the screw-type joint structure.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] According to the hole-drilling and stirring device of Patent Document 1, since the drilling bit vibrates in the vertical direction while rotating via a rod, it can efficiently drill even if there is a hard layer in the ground, and a soil-cement column can be constructed. However, as described above, the rotation direction of the rod provided with the drilling bit is limited to one direction around the axis. For this reason, for example, when there is a compacted backfill layer such as a gravel layer or slag in the ground, and the drilling bit rotates idly or bites into these layers during drilling and becomes unable to advance, measures such as reversing the rotation direction of the rod once cannot be taken.

[0006] Therefore, it was necessary to take measures such as raising the drilling bit together with the rod once, then appropriately rotating it to move the position of the drilling bit, and then lowering it to reach the bottom of the excavation surface and resume underground hole drilling, resulting in complicated construction operations.

[0007] In addition, when vertical vibration is applied to the rod via the vibration means, the screw-type joint structure is likely to loosen and cause rattling. 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 the hole-drilling efficiency due to the application of vibration.

[0008] As the joint structure used for connecting the rods, not only the screw-type joint structure of Patent Document 1 but also, for example, the flange-type joint structure as shown in Fig. 10(a) or the hexagonal joint pin-type joint structure as shown in Fig. 10(b) can be considered for adoption.

[0009] The flange-type joint structure 70 in Fig. 10(a) butts the flanges 71 and 72 provided at the ends of the steel pipes 31a and 31b arranged vertically, and fastens them with bolts 73. Such a flange-type joint structure 70 transmits the vertical vibration applied to the upper steel pipe 31b and the rotational force around the steel pipe axis to the lower steel pipe 31b via the bolts 73. Therefore, when there is a hard layer in the ground, it is necessary to increase the number of bolts 73 to cope with it, which requires a lot of time for the connection work. In addition, when the above-mentioned vertical vibration and rotational force around the steel pipe axis are repeatedly applied to the bolt joint, looseness is likely to occur. In such a case, the work is likely to become complicated, such as interrupting the construction and tightening the bolts again.

[0010] The hexagonal joint pin-type joint structure 80 in Fig. 10(b) fits the square tube portion 821 having a hexagonal cross section provided on the male joint 82 into the square hole portion 831 provided on the female joint 83, and then passes a pair of connection pins 81 through them. The pair of connection pins 81 are positioned at different heights on both sides sandwiching the axes of the male joint 82 and the female joint 83, and penetrate in a direction perpendicular to the axis. For this reason, a through hole 832 through which the connection pin 81 penetrates is provided in the square hole portion 831, and a notch 822 through which the connection pin 81 passes is provided in the square tube portion 821.

[0011] In such a hexagonal joint pin-type joint structure 80, if there is no play between the square hole portion 831 and the square tube portion 821 in the fitted state and the connection pin 81, the connection pin 81 cannot be inserted. Then, even if a vertical vibration is applied to the upper steel pipe 31b, there is a possibility that this vibration cannot be transmitted to the lower steel pipe 31a due to the play. Instead of a structure with play, for example, it is also conceivable to provide a taper on the connection pin 81 to make it wedge-shaped, but the processing is complicated and the manufacturing cost is high.

[0012] The present invention has been made in view of such problems, and its main object is to provide a hole-drilling agitator capable of transmitting the vertical vibration applied to the rod and the forward and reverse rotational forces around the rod axis to the excavation head provided at the tip of the rod.

Means for Solving the Problem

[0013] In order to achieve such an object, the hole-drilling and stirring machine of the present invention is a hole-drilling and stirring machine that excavates the ground with the excavation head by applying a rotational force and a vertical vibration to a rod having an excavation head connected to its tip. The rod has a rod body and a joint structure that connects the rod bodies in the axial direction. The joint structure includes a male joint provided with a flange on the outer peripheral surface and having a square tube portion, a female 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 clamps the flange of the male joint and the flange of the female joint. The cross-section where the flange of the male joint and the flange of the female joint are butted forms a taper that tapers toward the outer peripheral edge.

[0014] According to the hole-drilling and stirring machine of the present invention described above, the rod with the excavation head connected to its tip is composed of a plurality of rod bodies and a joint structure that connects the rod bodies. The male joint that constitutes the joint structure has a square tube portion, and the female joint has a square hole portion into which the square tube portion fits. Thus, the forward and reverse rotational forces applied to one of the rod bodies connected by the joint structure can be transmitted to the other through the square hole portion of the female joint and the square tube portion of the male joint that constitute the joint structure.

[0015] Also, the cross-section where the flange of the male joint and the flange of the female joint clamped by the pressing member are butted forms a taper that tapers toward the outer peripheral edge. Therefore, if a fitting groove that fits with this taper is provided in the pressing member, the flange of the male joint and the flange of the female joint will enter the fitting groove in a wedge shape, so that the clamping force in the vertical direction (the axial direction of the male joint and the female joint) increases, and the male joint and the female joint can be firmly clamped. Thus, the vertical vibration applied to one of the rod bodies connected by the joint structure can be transmitted to the other through the pressing member that constitutes the joint structure.

[0016] Therefore, it becomes possible to apply the vertical vibration and the rotational forces in the forward and reverse directions around the rod axis, which are applied to the proximal end of the rod formed by connecting a plurality of rod bodies with a joint structure, to the excavation head provided at the distal end of the rod. In this way, when there is a gravel layer in which gravel is compacted in the ground, for example, even if the excavation head rotates idly or bites into the gravel layer and excavation becomes impossible, countermeasures such as rotating the excavation head in the reverse direction via the rod can be taken. As a result, even when there is a gravel layer in the ground, the excavation work can be continued without performing complicated operations, and it becomes possible to significantly improve the workability related to ground excavation.

Effect of the Invention

[0017] According to the present invention, by connecting a plurality of rod bodies constituting a rod provided with an excavation head at the distal end with a joint structure using a convex joint having a square tube portion, a concave joint having a square hole portion into which the square tube portion fits, and a pressing member that sandwiches these, the vertical vibration applied to the rod and the rotational forces in the forward and reverse directions around the rod axis can be smoothly transmitted to the excavation head provided at the distal end of the rod.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0019] The hole-drilling agitator of the present invention will be described in detail with reference to FIGS. 1 to 9. In this embodiment, the case of constructing a subsurface hole is taken as an example, but the hole-drilling agitator can also be used to construct soil-cement columns.

[0020] ≪≪Hole-Drilling Agitator≫≫ As shown in FIG. 1, the hole-drilling agitator 1 used when excavating the target ground includes a crawler traveling body 2, an upper slewing body 3 mounted on the crawler traveling body 2, and a leader 4 supported so as to be able to be erected and tilted.

[0021] The leader 4 is provided with a guide 41 extending in the vertical direction on the front side thereof in the erected posture, and a lifting body 42 that moves up and down along the guide 41 is attached. On the back side, two telescopic devices 43 and 44 are provided, and the leader 4 and the upper slewing body 3 are connected via these. The leader 4 can be freely erected and tilted by the telescopic operation of the telescopic devices 43 and 44.

[0022] Further, the leader 4 is provided with a chuck mechanism 45 at its lower end. The chuck mechanism 45 may adopt any device as long as it has a configuration capable of gripping the rod 20 and the excavation head 10 described later. Further, the chuck mechanism 45 does not necessarily have to be mounted on the leader 4, and furthermore, a device separate from the hole-drilling agitator 1 may be adopted.

[0023] The hole-drilling agitator 1 further includes a vibration generating device 9 mounted on the lifting body 42, a rotating device 8 connected to the lower part of the vibration generating device 9, a drive shaft 7 passing through the rotating device 8 and having its proximal end connected to the vibration generating device 9, a rod 20 connected to the distal end of the drive shaft 7, and an excavation head 10 connected to the distal end of the rod 20.

[0024] The vibration generating device 9 is a device that generates an up-and-down vibration force by rotating an eccentric weight. Since it moves along the guide 41 via the lifting body 42, it moves in the lifting direction when the leader 4 is erected. Note that any vibration generating device 9 may be adopted as long as it can generate a vibration force capable of transmitting a vibration including a vertical component to the drive shaft 7.

[0025] The rotating device 8 is installed on the lifting body 42 and connected to the vibration generating device 9, and moves along the leader 4 in the erected posture together with the vibration generating device 9. Inside it, a drive shaft locking portion (not shown) is provided, which locks the peripheral surface of the drive shaft 7 and applies a rotational force in the forward or reverse direction around the axis.

[0026] The drive shaft 7 is composed of a single-layer pipe with a hollow portion, and a swivel joint 6 is attached to the middle thereof, and a fluid supply pipe 5 such as a cement milk supply pipe or a stabilizing fluid supply pipe is connected thereto. Thereby, it becomes possible to supply fluids such as cement milk and stabilizing fluid S supplied from the fluid supply pipe 5 from the swivel joint 6 through the drive shaft 7 to the rod 20. In FIG. 1, the case of supplying the stabilizing fluid S is taken as an example.

[0027] The rod 20 is composed of a rod body 30 and a joint structure 50 that axially connects the rod bodies 30. Its proximal end is connected to the drive shaft 7 via the joint structure 50, and its distal end is connected to the excavation head 10 via the joint structure 50. Details of the rod body 30 and the joint structure 50 will be described later.

[0028] The excavation head 10 includes a shaft portion 11 made of a single pipe having a hollow portion and connected to the rod 20, an excavation blade body 13 attached near the tip of the shaft portion 11 so as to extend laterally, and a bit 14 attached to the excavation blade body 13. Further, a plurality of stirring blades 12 extending in the radial direction are installed at a position on the shaft portion 11 that is spaced upward from the excavation blade body 13, and a tip bit 15 and a fluid discharge port 16 are provided at the tip of the shaft portion 11.

[0029] The bit 14 and the tip bit 15 have a shape that can excavate the ground when the excavation head 10 rotates in either the forward or reverse direction around the rod axis. 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 the present embodiment, since the underground hole H is being excavated, the fluid discharged from the fluid supply pipe 5 is the stabilizing fluid S. However, if cement milk is used as the fluid, it is also possible to construct a soil-cement column instead of the underground hole H.

[0030] Further, the stirring blades 12 provided on the excavation head 10 are used when constructing the soil-cement column as described above, for example, when discharging and stirring the cement milk from the fluid discharge port 16 while excavating the ground, or when supplying a cement-based solidifying material to the underground hole H and stirring it with the stabilizing fluid after constructing the underground hole H.

[0031] ≪≪Details of the Rod≫≫ In the boring and stirring machine 1 having the above-described configuration, the rod 20 has a configuration capable of transmitting the vertical vibration applied from the vibration device 9 via the drive shaft 7 and the forward and reverse rotations around the rod axis applied from the rotation device 8 to the excavation head 10. Hereinafter, the details of the rod body 30 and the joint structure 50 that constitute the rod 20 will be described. Since the joint structure 50 is also adopted for connecting the drive shaft 7, the excavation head 10, and the rod 20, these will also be described together.

[0032] ≪≪Rod Body≫≫ As shown in Fig. 2, the rod body 30 includes a pipe member 31, and a male joint 32 and a female joint 33 provided at both ends thereof.

[0033] The pipe member 31 is composed of a single pipe similar to the shaft portions 11 of the drive shaft 7 and the excavation head 10 described above, and has a hollow portion 311 through which the fluid supplied from the fluid supply pipe 5 flows down. A male joint 32 is connected to one end thereof, and a female joint 33 is connected to the other end thereof. In Fig. 2, a state in which the pipe member 31 is erected with the male joint 32 on the upper side is illustrated.

[0034] The male joint 32 is composed of a cylindrical body provided with a hollow portion 321 communicating with the hollow portion 311 of the pipe member 31. The base end side is formed as a cylindrical portion 322 having the same size and outer shape as the pipe member 31 in cross section, and is fixed to the pipe member 31 by fixing means such as welding. On the other hand, the tip end side is formed to have a smaller cross section than the pipe member 31, and is a square tube portion 323 formed in a hexagonal donut shape as shown in Fig. 3(a).

[0035] A convex flange 324 is provided in the vicinity of the boundary between the cylindrical portion 322 on the base end side and the square tube portion 323 on the tip end side. The convex flange 324 is formed so as to project from the outer peripheral surface of the cylindrical portion 322, and is formed in a frustum shape having the square tube portion 323 side as the bottom surface and the cylindrical portion 322 side as the side surface. As shown in Fig. 6, the square tube portion 323 side becomes the opposing surface 324a with the concave flange 334 described later, and the cylindrical portion 322 side becomes the contact surface 324b with the pressing member 40 described later.

[0036] As shown in Fig. 2, the female joint 33 is formed as a housing cylinder portion 332 having the same size and outer shape as the pipe member 31 in cross section over the entire length, and a hollow portion 331 communicating with the hollow portion 311 of the pipe member 31 is provided on the base end side. On the other hand, a square hole portion 333 that fits with the square tube portion 323 of the male joint 32 is formed on the tip end side, and the square hole portion 333 and the hollow portion 331 communicate with each other. The inner peripheral cross section of the square hole portion 333 is formed in a hexagon having the same size as the outer peripheral surface of the square tube portion 323 as shown in Fig. 3(b).

[0037] And a concave flange 334 is provided at the tip of the storage cylinder portion 332. The concave flange 334 is formed so as to project from the outer peripheral surface of the storage cylinder portion 332, and is formed in a frustum shape with the tip side as the bottom surface and the pipe material 31 side as the side surface. As shown in FIG. 6, the tip side becomes the opposing surface 334a with the above-described convex flange 324, and the pipe material 31 side becomes the contact surface 334b with a pressing member 40 to be described later.

[0038] ≪≪Joint structure 50≫≫ As shown in FIG. 1, a plurality of rod bodies 30 having the above-described configuration are arranged in parallel in the axial direction, and a joint structure 50 composed of a male joint 32 and a female joint 33 provided on the rod body 30 and a pressing member 40 is formed between adjacent rod bodies 30, thereby forming the rod 20.

[0039] That is, as shown in FIGS. 4(a) and 4(b), the square tube portion 323 constituting the male joint 32 of the lower rod body 30a is inserted into and fitted into the square hole portion 333 constituting the female joint 33 of the upper rod body 30b, and the opposing surface 324a of the convex flange 324 is brought into contact with the opposing surface 334a of the concave flange 334. Thereby, the rotational force in the forward and reverse directions applied to the upper rod body 30b can be transmitted to the lower rod body 30a through the square hole portion 333 of the female joint 33 and the square tube portion 323 of the male joint 32.

[0040] At this time, a rod packing 60 is interposed between the tip of the square tube portion 323 of the male joint 32 and the square hole portion 333 of the female joint 33. The rod packing 60 is formed in a ring shape with a hole provided in the center so as to maintain the communication state of the hollow portions 321 and 331 of the male joint 32 and the female joint 33.

[0041] In this way, the convex flange 324 and the concave flange 334 with the opposing surfaces 324a and 334a abutted against each other are clamped by a pressing member 40 as shown in FIGS. 5(a) and 5(b). Thereby, the vertical vibration applied to the upper rod body 30b can be transmitted to the lower rod body 30a through the pressing member 40.

[0042] <<Pressing member 40>> The pressing member 40 that constitutes the joint structure 50 as described above includes split members 401 and 402 and a fastener 403, and the fastener 403 includes a bolt 403a and a nut 403b.

[0043] As shown in Fig. 5(a), the split members 401 and 402 are formed by splitting a ring-shaped member of a size that can surround the convex flange 324 of the male joint 32 and the concave flange 334 of the female joint 33. At both circumferential ends of the split member 401, ear portions 401b protruding in the radial direction are provided. Bolt holes through which the bolt 403a passes are formed in these ear portions 401b. Similarly, ear portions 402b are provided at both circumferential ends of the split member 402, and bolt holes through which the bolt 403a passes are formed.

[0044] Also, a fitting groove 401a continuous in the circumferential direction is formed on the inner peripheral surface of the split member 401. As shown in Fig. 6, its cross-sectional shape is formed to fit with the convex flange 324 and the concave flange 334 when they are inserted with their opposing surfaces 324a and 334a butted together. Since the cross-section of the butted convex flange 324 and concave flange 334 forms a taper that tapers towards the outer peripheral edge, the fitting groove 401a is formed as a substantially V-shaped tapered groove that can fit with this taper. A fitting groove 402a continuous in the circumferential direction is also formed in the split member 402, and a substantially V-shaped tapered groove similar to the fitting groove 401a is formed.

[0045] The installation procedure of the pressing member 40 having the above configuration is as follows. As shown in Fig. 5(a), the split members 401 and 402 are arranged so as to surround the butted convex flange 324 and concave flange 334, and these are inserted and fitted into the fitting grooves 401a and 402a. As a result, the ear portions 401b and 402b of the split members 401 and 402 face each other. Therefore, as shown in Fig. 5(b), the bolt 403a is inserted through the bolt holes formed in the ear portions 401b and 402b, and the nut 403b is screwed and tightened.

[0046] Then, as shown in FIG. 6, as the split members 401 and 402 gradually approach each other, the convex flange 324 and the concave flange 334 enter the fitting grooves 401a and 402a in a wedge shape. At this time, both of the fitting grooves 401a and 402a secure a groove depth D such that the outer peripheral end faces of the convex flange 324 and the concave flange 334 do not contact the groove bottom. As a result, the convex flange 324 and the concave flange 334 can penetrate sufficiently into the fitting grooves 401a and 402a, so that the clamping force in the vertical direction (the axial direction of the male joint 32 and the female joint 33) increases, and the male joint 32 and the female joint 33 can be firmly clamped.

[0047] Therefore, even when vibrations in the vertical direction are transmitted from the female joint 33 side, it is possible to transmit these vibrations in the vertical direction to the male joint 32 side via the pressing member 40 without causing rattling. The tightening effect of the pressing member 40 on the convex flange 324 and the concave flange 334 is preferably set such that the taper angle θ of the cross section where the convex flange 324 and the concave flange 334 are butted against each other is about 10 to 60°, and more preferably about 26°.

[0048] Note that, for example, an eyebolt E as shown in FIG. 6 may be provided on the pressing member 40. In this way, when attaching and detaching the pressing member 40, it becomes possible to take measures to prevent dropping by suspending the pressing member 40 with a wire using the eyebolt E.

[0049] As shown in FIG. 1, the above-described joint structure 50 is also adopted for the connection between the rod 20 and the drive shaft 7 and for the connection between the rod 20 and the excavation head 10. In FIG. 1, the female joint 33 is disposed on the lower end side of the rod body 30 in the standing state, and the male joint 32 is disposed on the upper end side. Therefore, following this, the male joint 32 is installed at the upper end of the excavation head 10, and the female joint 33 is installed at the lower end of the drive shaft 7.

[0050] Also, when constructing a long underground hole H, the rod body 30 can be easily added and the rod 20 can be extended by using the joint structure 50, and the extended rod 20 can be connected to the drive shaft 7. Hereinafter, the procedure for adding a new rod body 30c and extending the rod 20 will be described.

[0051] ≪Procedure for adding the rod body≫ As shown in Fig. 7(a), the ground is excavated to construct the underground hole H by transmitting the forward rotational force by the rotating device 8 and the vertical vibration by the oscillating device 9 from the drive shaft 7 through the rod 20 to the excavation head 10. When starting the underground hole drilling, the following preparatory work is carried out.

[0052] The boring mixer 1 is installed so that the leader 4 with the guide 41 arranged in the erected posture via the telescopic devices 43 and 44 is arranged at a predetermined position. Next, the excavation planned position is pre-excavated in advance, the excavation head 10 is inserted, and the rod body 30 is connected to the shaft portion 11 of the excavation head 10 and the drive shaft 7. As described above, all of these are connected by providing the joint structure 50.

[0053] Specifically, as shown in Fig. 1, the male joint 32 of the shaft portion 11 and the female joint 33 of the rod body 30 are fitted, and the pressing member 40 is attached thereto to provide the joint structure 50, thereby connecting the shaft portion 11 and the rod body 30. Similarly, the male joint 32 of the rod body 30 and the female joint 33 of the drive shaft 7 are fitted, and the pressing member 40 is attached thereto to provide the joint structure 50, thereby connecting the rod body 30 and the drive shaft 7.

[0054] During construction, as shown in Fig. 7(a), the stabilizing fluid S is supplied from the fluid supply pipe to the drive shaft 7 via the swivel joint, and discharged from the fluid discharge port 16 into the ground hole H through the rod 20 and the shaft portion 11 of the excavation head 10. The stabilizing fluid S filling the ground hole H is discharged using the vacuum hose V inserted into the hole. As shown in Fig. 7(b), as 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 vibration device 9 are temporarily stopped.

[0055] With the rod body 30 constituting the rod 20 being gripped by the chuck mechanism 45, the pressing member 40 is removed from the joint structure 50 that connects the rod body 30 and the drive shaft 7. After removing the pressing member 40, as shown in Fig. 7(c), the lifting body 42 on which the rotating device 8 and the vibration device 9 are installed is raised along the guide 41. In this way, the male joint 32 provided at the upper end of the rod body 30 is exposed, and the female joint 33 provided at the lower end of the drive shaft 7 is exposed. Also, a working space is provided between the female joint 33 of the drive shaft 7 and the male joint 32 of the rod body 30 for adding a new rod body 30c.

[0056] Using this working space, as shown in Fig. 8(a), a new rod body 30c is connected to the drive shaft 7 and the rod body 30 gripped by the chuck mechanism 45. Specifically, as shown in Fig. 8(b), the male joint 32 of the rod body 30 gripped by the chuck mechanism 45 and the female joint 33 of the new rod body 30c are fitted together, and the pressing member 40 is attached to them to provide the joint structure 50. Thereby, a new rod body 30c is added, and the member length of the rod 20 is extended.

[0057] After that, while appropriately adjusting the height position of the drive shaft 7 using the elevating body 42, the male joint 32 of the new rod body 30c and the female joint 33 of the drive shaft 7 are fitted together, and the pressing member 40 is attached to them to provide the joint structure 50. As a result, since the rod 20 with the extended member length hangs down from the drive shaft 7, the chuck mechanism 45 is released, and as shown in Fig. 9(c), the rotating device 8 and the oscillating device 9 are operated to resume the construction work of the underground hole H.

[0058] In such a procedure, the rod 20 with the rod body 30 added via the joint structure 50 smoothly transmits the forward rotational force by the rotating device 8 and the vertical vibration by the oscillating device 9 applied via the drive shaft 7 to the excavation head 10 connected to the tip side of the rod 20. Therefore, even when there is a hard layer in the ground during excavation, it is possible to continue excavation by impact crushing with the bits 14 and the tip bit 15 of the excavation head 10 to which the vertical vibration is transmitted, or by moving large gravel by vibration.

[0059] Also, the joint structure 50 employs a pressing member 40 and does not use a pair of connection pins 81 such as the hexagonal joint pin type joint structure 80 shown in Fig. 10(b) described as one of the prior arts. For this reason, it is possible to shorten the fitting range of the male joint 32 and the female joint 33. That is, when a pair of connection pins 81 is employed, as shown in Fig. 10(b), a through hole 832 through which the connection pin 81 passes is provided in the square hole portion 831, and a notch 822 through which the connection pin 81 passes is provided in the square tube portion 821, with their positions shifted in the height direction. However, since the square hole portion 333 and the square tube portion 323 of the joint structure 50 can omit these, the height can be set lower, so the fitting range also becomes smaller.

[0060] Accordingly, without changing the overall length of the rod body 30, the member length of the pipe material 31 can be increased by the amount by which the fitting range of the male joint 32 and the female joint 33 is shortened. Then, even when the construction target area is in a low-ceilinged space and there are limitations in securing a working space for adding the rod body 30, it becomes possible to reduce the number of rod bodies 30 to be added to extend the rod 20. Along with this, the number of times of the operation of adding the rod body 30 can also be reduced, so that the working efficiency when constructing the underground hole H can be significantly improved, contributing to shortening the construction period.

[0061] Furthermore, when performing underground boring with the boring and agitating machine 1, if there is a gravel layer G in which gravel is compacted as shown in Fig. 9(a), the bits 14 and the tip bit 15 of the boring head 10 may bite into the gravel layer G, or the separated gravel may enter between the gravel layer G and the boring head 10 and the boring head 10 may idle, resulting in a situation where boring cannot be performed. In such a case, as shown in Fig. 9(b), measures such as applying a reverse rotational force around the axis to the rod 20 with the rotating device 8 can be taken.

[0062] As a result, even when there is a gravel layer G in the ground, the boring operation can be continued without performing complicated operations, and it becomes possible to significantly improve the workability related to underground boring. At this time, since the boring head 10 has a structure that can bore with either forward or reverse rotation, the boring may proceed while rotating in the reverse direction, or the boring operation may be resumed by switching to forward rotation.

[0063] The boring and agitating machine of the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention.

[0064] For example, in the present embodiment, as shown in Fig. 4, the square tube portion 323 of the male joint 32 and the square hole portion 333 of the female joint 33 are formed in a hexagonal shape, but it is not necessarily limited to this. Any shape such as a triangular shape or a square shape may be adopted as long as the shapes of the male joint 32 and the female joint 33 do not rotate relative to each other around the axis.

[0065] Further, in the present embodiment, on the rod body 30 in the standing posture, the male joint 32 is disposed at the upper end and the female joint 33 is disposed at the lower end, but the present invention is not limited thereto. It may be reversed up and down, or a rod body 30 having male joints 32 disposed vertically and a rod body 30 having female joints 33 disposed vertically may be prepared, and a combination of the two may be connected by the joint structure 50 to form the rod 20.

[0066] Furthermore, in the present embodiment, as shown in FIG. 5(a), the pressing member 40 is composed of split members 401 and 402 and a fastener 403, and a total of four bolts 403a and nuts 403b are employed for the fastener 403, but the quantity may be any number. Also, as shown in FIG. 6, if it is possible to apply a vertical tightening force to the convex flange 324 and the concave flange 334, the fastener 403 is not limited to the combination of the bolt 403a and the nut 403b.

[0067] In addition, the split members 401 and 402 do not necessarily have to be separate bodies. For example, a hinge member may be provided for one combination of the two sets of ear portions 401b and 402b, and the other combination may be tightened with bolts 403a and nuts 403b.

Explanation of Reference Numerals

[0068] 1 Hole-drilling agitator 2 Crawler traveling body 3 Upper slewing body 4 Leader 41 Guide 42 Lifting body 43 Telescopic device 44 Telescopic device 45 Chuck mechanism 5 Fluid supply pipe 6 Swivel joint 7 Drive shaft 8 Rotating device 9 Vibration generating device 10 Excavation head 11 Shaft portion 12 Agitating blade 13 Excavation blade body 14 bits 15 tip bits 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 material 31a steel pipe (lower side) 31b steel pipe (upper side) 32 male joint 321 hollow part 322 cylindrical part 323 square tube part 324 convex flange 324a opposing surface 324b contact surface 33 female joint 331 hollow part 332 storage cylinder part 333 square hole part 334 concave flange 334a opposing surface 334b contact surface 40 pressing member 401 split member 401a fitting groove 401b ear part 402 split member 402a fitting groove 402b ear part 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 connecting pin 82 male joint 821 square tube part 822 notch part 83 female joint 831 Angular hole part G Gravel layer H Subsurface hole V Vacuum hose E Eyebolt S Stabilizing liquid

Claims

【Claim 1】 A hole-drilling and stirring machine for excavating the ground with the excavation head, by applying a rotational force and a vertical vibration to a rod having an excavation head connected to its tip, wherein the rod has a rod body and a joint structure for connecting the rod bodies in the axial direction, the joint structure is, a male joint provided with a flange on the outer peripheral surface and having a square tube portion, a female joint provided with a flange on the outer peripheral surface and having a square hole portion that fits into the square tube portion, and a pressing member that abuts and clamps the flange of the male joint and the flange of the female joint, the hole-drilling and stirring machine being characterized in that a cross-section where the flange of the male joint and the flange of the female joint are abutted forms a taper that tapers toward the outer peripheral edge.

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