JPS6024796Y2 - Extended head for drilling - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an expansion head for excavation, and particularly to an expansion head for an excavator used in combination with an excavator such as an auger screw for erecting ready-made hollow piles.

Conventionally, this kind of expansion head for erecting ready-made hollow piles has an expansion force seat at the tip of the auger screw, one end of the drilling blade is pivotally attached to this seat with a pin, and the hole is drilled when the auger screw rotates. The screw blades are expanded in the outer circumferential direction due to the resistance of the earth and sand, and a hole with approximately the same diameter as the pile diameter is drilled.

However, the excavation blade of the conventional expansion head is pushed out by the rotation of the screw and the soil resistance of the excavated ground, so if the soil of the excavated ground is soft, for example,
In cases where the soil is clayey, the expansion blade often fails to open, making it impossible to expand the excavation to the same diameter as the pile, which often leads to a situation where the pile cannot be erected.

Further, since the conventional expanding blades of this type project horizontally, they do not have a soil lifting action, and therefore have the disadvantage that the soil removal efficiency around the expanding force is poor.

In view of this, the present invention aims to provide an expansion head for excavation that can solve the problems of the prior art. Regardless of the situation, the expansion blade is expanded, thereby ensuring reliable expansion of digging and improving the efficiency of excavation and removal.

The present invention will be explained below with reference to embodiments shown in the drawings.

FIG. 1 shows a side view of an embodiment of an expansion head according to the present invention.
2 shows the upper surface, FIG. 3 shows the lower surface, and FIG. 4 shows an enlarged cross section taken along the line IV--IV in FIG. 3.

As shown in FIG. 1, the expansion head 1 according to the present invention includes a shaft portion 4 connected to the lower end of the shaft portion 3 of the auger screw 2, and a shaft portion 4 fixedly attached to the outer periphery of the shaft portion 4. When connected to the lower end of the part 3, the screw blade 6 is connected to the end of the screw blade 5 of the auger screw 2 in a continuous form.
An expansion blade 7 is attached to the end of the blade.

In this embodiment, the screw blade 6 of the expansion head 1 has double blades 6, 6, and a pair of expansion blades 7, 7 are provided at the lower ends of these blades 6, 6, respectively.

As shown in one enlarged cross section in FIG. 4, this expansion blade 7 has a mounting base 8 that is fitted to sandwich the distal edge 6a of the blade 6 from above and below, and the front end of this mounting base 8. A digging blade 7 is fixedly attached to the blade 6, and is rotatably attached along the surface of the blade 6 by a shaft 9 protruding from the upper and lower surfaces of the blade 6.

As shown in FIG. 2, the planar shape of the mounting base 8 is such that the outer end portion 8a on the end side where the excavating blade 7 is provided can protrude outward beyond the outer peripheral edge 6b of the blade 6. When the pile 10 is extended on substantially the same radius as the outer periphery of the pile 10, the base end comes into contact with a stopper 11 provided on the blade 6, and is restricted from extending any further.

Note that the digging blade 7 can be set to any enlarged diameter by changing the position of this stopper 11.

The shaft 9 is hollow, and a coil spring 12 is fitted inside, one end of which is fixed to a protrusion 14 of an auxiliary member 13 fixed to the blade 6, and the other end fixed to the mounting base 8 at the opposite end of the shaft 9. The outer end portion 8a of the excavating blade 7 has a tendency to protrude outward by being biased by the torsional force of the coil spring 12.

Note that an auger screw 2 is attached to the shaft portion 4 of the drilling head 1.
A passage 17 is provided which is connected to a chemical liquid passage, and a chemical liquid such as mortar can be injected from a valve 18 at the lower end of the head if necessary.

Next, the operation of the above embodiment will be explained.

First, insert the expansion blades 7, 7 into the hollow part of the ready-made hollow pile 10,
The tip thereof is made to protrude from the tip of the hollow pile 10.

In this case, the expansion blades 7, 7 are housed and inserted into the hollow pile 10 in a reduced diameter state, and at the same time as they protrude from the tip of the hollow pile 10, the coil spring 12 biases the expansion blades 7, 7 toward the outside of the pile tip so that the outer diameter of the pile is approximately the same. Expands to the diameter.

In this way, the auger screw 2 is rotationally driven, and the extended blade 7,
7 excavates the tip of the hollow pile 10, and the hollow pile 10 is erected while removing the soil using the screw blades 6, 6.

After the excavation to a predetermined position is completed, the auger screw 2 is pulled up.

In this case, the extended blades 7, 7 have their outer ends 8a. 8a contacts the lower end of the hollow pile 10, is reduced in diameter against the coil spring 12, and is extracted through the inside of the hollow pile 10.

During the above-mentioned excavation, the tip edges 6 of the blades 6, 6 of the expansion head 1
Since excavation blades 7, 7 are placed along the slope of the blades 6, 6a, they act as cutting blades, increasing excavation efficiency, and at the same time, immediately after excavation, the soil is placed on the blades 6, 6 and removed. It is possible to improve soil removal efficiency.

In addition, in the above embodiment, the blades 6 of the expansion head 1,
6 has a double structure and the excavation blades 7, 7 are attached to the tip edges 6a, 6a of each blade 6, 6, respectively, but the blade of the expansion head 1 is also a single layer similar to the auger screw 2, The extended blade 7 may be a single one.

As explained above, in the present invention, the expansion head connected to the lower end of the auger screw is provided with a screw blade that is continuous with the screw blade of the screw, and the excavation blade is driven by a shaft equipped with a coil spring at the tip edge of the screw. Since it is pivoted and biased in the direction of expansion, the excavation blade forms part of the screw blade for excavation, allowing for efficient excavation like a cutting blade, and the excavated soil is immediately transferred to the blade. Since the soil is carried upward by the expansion head, the soil can be quickly and efficiently removed from the tip of the expansion head, significantly improving the excavation and soil removal efficiency.Moreover, the expansion blade can be expanded reliably regardless of the geology of the ground. It has various excellent effects such as making it easier to erect hollow piles.

[Brief explanation of the drawing]

Fig. 1 is a side view showing one embodiment of the expansion head according to the present invention, Fig. 2 is a plan view taken along the line ■-■ in Fig. 1, Fig. 3 is a bottom view of the same, and Fig. 4 is a FIG. 1...Expansion head, 2...August screw, 3.4...Shaft part, 5, 6...
Screw blade, 7...Expansion blade, 8...
・Mounting base, 9... shaft, 10... hollow pile, 11... stopper, 12... coil spring, 13... auxiliary Members, 14, 16...
... Protrusion, 15... Cap.

Claims (1)

[Claims for Utility Model Registration] 1. A screw blade continuous to the screw blade of the auger screw is provided on the outer periphery of the shaft of an expansion head connected to the lower end of the shaft of the auger screw, and a screw blade is provided at the lower end tip of the screw blade. An extended head for excavation, in which the base of an excavation blade is rotatably supported by a shaft, and the outer end of the excavation blade is biased in a direction to protrude from the outer peripheral edge of a screw blade. 2 The shaft for pivotally supporting the excavation blade is a hollow shaft, and one end of the coil spring fitted into the shaft is fixed to the screw blade side fixing member.The lumbosacral end is fixed to the excavation blade side end member and the coil spring is fixed. The extended head for excavation according to claim 1, characterized in that the excavation blade has a protruding habit due to torsional force.