JPS6311515B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drilling bucket for widening the tip used for creating a pile with an enlarged tip in a cast-in-place pile construction method using an earth drilling method.

As the above-mentioned drilling bucket for widening the tip, the present applicant has proposed a structure in which the widening blades provided on the sides are automatically opened and closed by rotating the bucket main body forward and backward (Japanese Patent Publication No. 57-8276). This method has a simple structure and has the effect of requiring little excavation power, but it is difficult to push up the earth and sand that has been excavated to widen the width and stored in the bucket by forward rotation to the upper part of the bucket, and by reverse rotation the widening blades When blocking the bucket, there may be problems such as the soil inside the bucket overflowing in some cases.

Furthermore, the bottom expansion pile using the conventional earth drilling method is
After completing the shaft excavation using the earth drilling method, a bottom expanding excavator is inserted into the hole and the bottom expanding excavation is performed using the reverse circulation method, so separate mechanical equipment is used for each. , which requires a large area and leads to high costs.
Replacement requires time and effort, and the work may be difficult due to limited site area.

The present invention has been made in view of the above problems, and the widening wings are opened and closed regardless of the rotating direction of the bucket main body, and the earth and sand stored in the main body are pushed up to increase the amount of earth and sand stored. The purpose of the present invention is to provide a drilling bucket for widening the tip, which allows drilling to be performed simultaneously.

Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

The tip widening drilling bucket 1 includes a cylindrical bucket main body 2. The main body 2 is constituted by a steel pipe having a diameter and a required length to be inserted into a borehole drilled by a conventional method, and forms the outer rim of the drilling bucket 1.

A beam 3 is fixed to the inner surface of the upper end of the main body 2, and a plurality of stabilizers 4 whose diameters are slightly smaller than the drilling diameter are provided on the outer periphery of the upper end to stabilize the main body 2.

The side surface of the main body 2 has a bottom edge 2a as shown in FIG.
A substantially triangular window hole 5 with an open lower part, which is made up of a side 2b forming a right angle with the side 2b, a sloped part 2c continuous to the upper part of the side, and a vertical part 2d hanging from the upper end of the sloped part, is bored and fits into the window hole 5. A substantially triangular width widening excavation blade 6 (hereinafter simply referred to as a widening blade) is hinged to the vertical portion 2d with a hinge 7 so as to be openable and closable. A large number of pawls 8 are provided on the outer periphery of the widening blade 6, that is, on the slope portion 6a and the vertical portion 6b continuous to the lower end thereof, to facilitate widening excavation. Although the illustrated example shows an example in which two widening blades 6, 6 are provided symmetrically, the number is not necessarily limited to two, and three or more may be provided symmetrically.

A hydraulic cylinder 10 is attached to the lower surface of the center of the beam 3, and a bearing 11 provided at the tip of the piston rod of the hydraulic cylinder 10 and a bearing 12 provided at an appropriate position on the widening blade 6 are connected by a link 13. .

Further, a Kelly bar connecting shaft 14 of an excavator (not shown) is attached to the upper part of the beam 3. This Kelly bar connecting shaft 14 has a Kelly bar insertion hole 15 and a pin hole 1.
6, inserting the Kelly bar into the insertion hole 15,
A pin is inserted into the pin hole 16 and connected integrally, and the main body 2 is rotated together with the Kelly bar.

A swivel joint 17 is attached to the lower outer periphery of this Kelly bar connection shaft 14, and the inlet side of the joint 17 is connected to a ground pressure oil supply means (not shown).
A hydraulic hose 18 is connected to the hydraulic cylinder 10, and the outlet side thereof is connected to the hydraulic cylinder 10. As a result, even if the drilling bucket 1 rotates, the hydraulic hose does not become entangled.

The illustrated example shows an example in which the swivel joint 17 is attached to the beam 3, but the swivel joint 17
may be operated by being attached to the lower end of the front frame of the earth drill machine body (not shown).

A bottom cover 20 is detachably attached to the lower end of the main body 2. A stopper 21 corresponding to the hydraulic cylinder 10 is provided at the center of the bottom cover 20 to restrict the lowering of the bearing 11, that is, the opening degree of the widening blades 6.

The bottom cover 20 is provided with bottom cleaning means 22. This bottom scooping means 22 is provided with a dirt inlet 23 bored in the bottom cover 20 , the outer edge of this dirt inlet 23 has a width approximately equal to the lower edge of the window hole 5 , and the bottom cover 20 is located at the center of the bottom cover 20 . It is formed in a triangular shape connecting the A plurality of pawls 24 are provided on the rear slope of the earth and sand inlet 23 in the direction of bucket rotation, and a shutter 25 is attached to the opposite slope with a hinge 26 so as to be openable and closable. As a result, when the earth and sand enter, the shutter 25 is pushed and floats, allowing the earth and sand to enter the main body 2, and covers the entrance 23 when the main body 2 is pulled up.

An auger screw 30 is provided inside the main body 2 to facilitate the storage of earth and sand excavated by the widening blades 6. The auger screw 3
The shaft core 31 has an inner diameter slightly larger than the outer diameter of the hydraulic cylinder 10 and the stopper 21, and a screw blade 32 is attached to the outer periphery of the shaft core 31. A cut groove 33 is provided in the shaft core 31 and the screw blade 32 so as not to hinder the vertical movement of the link 13 accompanying the operation of the hydraulic cylinder 10, and an engagement groove 34 is formed at the lower end.
4 is fitted into a protrusion 35 provided at the center of the bottom cover 20. 36 is a bottom cover mounting bolt, which is attached to the bottom cover 2.
A protrusion 37 protruding outward from the main body 0 and a bottom plate engaging plate 38 attached to the outer side of the lower part of the main body are connected to form one body.

In the figure, reference numeral 40 denotes a fishtail attached to the lower surface of the center of the bottom cover, which prevents the bottom of the main body 2 from swinging out.

In the above configuration, first, a hole is drilled to a predetermined depth using a conventional earth drilling method, the drilling bucket 1 is inserted into the hole, and the slime at the bottom of the hole is washed out by means of forward rotation. After the oil is removed by the hydraulic hose 18 and the bottom is sanded, the oil is supplied to the hydraulic cylinder 10 via the swivel joint 17 with the hydraulic hose 18 while the rotation is still the same, the hydraulic cylinder 10 is operated, and the width is widened by the link 13. Widening excavation is performed while opening the wings 6, 6. The excavated earth and sand enters the main body 2 through the window hole 5 and is lifted up by the auger screw 30, making it easier for the following earth and sand to enter.

After completing the excavation to a predetermined widening dimension by the stopper 21, while continuing to rotate in the same direction, the operation of the hydraulic cylinder 10 is switched, and the widening blade 6 is gradually closed by the link 13, leaving the excavated soil. It is stored in the drilling bucket main body 2 without any damage, and then the drilling bucket 1 is pulled up. In the salvaged drilling bucket 1, the bolt 36 is removed to separate the main body 2 and the bottom cover 20, and the auger screw 30 is pulled out to completely remove the earth and sand.

As described above, according to the present invention, widening excavation can be performed regardless of the direction of rotation of the bucket main body, and since the auger screw is provided in the main body, the incoming earth and sand are pushed up and the subsequent earth and sand can easily enter. Therefore, it is possible to increase the storage amount of earth and sand. Further, by using the above-mentioned widening drilling bucket, turning can be easily carried out by replacing only the drilling bucket used for excavating the shaft.

Therefore, the inconvenience of conventionally performing axial excavation and widening excavation using separate tools is eliminated, and it is possible to reduce construction costs and shorten the construction period by improving efficiency, and also eliminates the need to replace excavation tools. Because there is no space available, it has the advantage of being able to work efficiently even in places with a small site area.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 is a longitudinal sectional view of the entire drilling bucket, Fig. 2 is a front view of the main body, Fig. 3 is a plan view of the main body, and Fig. 4 is a partially cutaway view. The overall perspective view shown in FIG.
FIG. 6 is a longitudinal sectional view of the bottom cover, and FIG. 7 is a front view of the auger screw. 1...Drilling bucket, 2...Main body, 5...
... Window hole, 6 ... Excavation wing for widening, 10 ... Hydraulic cylinder, 13 ... Link, 17 ... Swivel joint, 18 ... Hydraulic hose, 20 ... Bottom cover, 22
... Means of bottoming out, 30... Auger Screw.

Claims (1)

[Claims] 1. On the side of the cylindrical body with a steel pipe of the required diameter,
A substantially triangular window hole is provided, and on one side of this window hole, a widening excavation blade of a shape that fits the window hole is attached,
The digging blade is connected via a link to a hydraulic cylinder attached to the center of the main body, and the hydraulic cylinder is connected to a hydraulic hose via a swivel joint to open and close the digging blade. For widening the tip of an earth drill method, characterized in that a lid is removably attached to the bottom lid, an auger screw is removably attached to the bottom lid located at the center of the main body, and a means for cleaning the bottom is provided. Drilling Bucket.