JPS6329074B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a bucket-type excavator used for excavating vertical holes in civil engineering and construction underground construction work, particularly for excavating holes for site concrete reinforcement construction.

(Conventional structure and problems) In underground construction work in civil engineering and construction, it is often necessary to excavate a large vertical hole underground.

Particularly when constructing concrete pits in situ, vertical holes of large diameter and great depth must be drilled prior to concrete pouring.

In this case, a method is usually used in which a cutting tool (auger, drill, etc.) with the required diameter is pushed into the ground and rotated to excavate the earth and sand. In order to smooth the discharge, a method is used in which bentonite mud is injected into the borehole.

However, when this method is used, bentonite wastewater discharged together with excavated soil flows into rivers, ponds, etc., causing pollution problems.

Therefore, a method has been used in which a metal cylindrical casing is inserted into the ground without using bentonite mud, and a cutting tool is rotated within the casing while preventing the collapse of the borehole wall earth and sand to perform excavation.

However, in this case, a large amount of force is required to push the casing into the soil, and when the casing is pulled out, a large pulling force is required because the earth and sand that has become muddy due to groundwater etc. sticks to the outer wall of the casing. The actual situation is that the equipment for these is extremely large-scale, and it is extremely difficult to drill holes with large diameters and deep holes.

Furthermore, in any of these conventional construction methods, it is difficult to remove large boulders, rock blocks, etc. that are mixed with the earth and sand and removed, and special means are required for this purpose.

(Technology related to the invention) As an example of a new proposal that can solve the problems of the conventional method as described above, a drilling bucket is inserted into a cylindrical casing inserted into the ground and rotated. An excavation method in which a cutting tool installed along the outer circumference of the lower end of the hole bucket protrudes slightly from the lower edge of the casing to excavate the earth and sand, and at the same time circulates fluid such as water from inside the casing to the inside of the bucket to discharge the earth and sand. There is.

To explain this proposed example with reference to Fig. 1, 1 is a casing made of a short cylindrical thin-walled metal tube inserted into the soil, and a metal drum-shaped drilling bucket 2 is charged into this casing. .

A discharge port 2a is opened on the top surface of the drilling bucket 2, and a rotary rod 3 made of a hollow metal tube is connected to this. are attached by pivoting means.

The drilling tool 4 is constructed so that its cutting edge rotation locus can be expanded or contracted by forward or reverse rotation of the drilling bucket 2, and when drilling, the casing 1 is
The cutting edge is enlarged below the lower end, the rotating rod 3 is rotated by a rotating device (not shown) provided on the ground, and the excavating blade 4 is rotated via the drilling bucket 2 to perform excavation.

A fluid, for example water, is fed into the casing 1 by a circulating water device (not shown), flows as shown by the arrow, and is injected from the gap between the casing 1 and the bucket 2 to the vicinity of the excavating tool 4, and the earth and sand cut down by the cutting edge is removed along with the water flow. Water is sucked into the drilled bucket 2 through the opening (intake) at the bottom of the bucket, is discharged to the ground through the outlet 2a through the rotary rod 3, and has the earth and sand separated by the circulating water system. is fed into the casing 1 again and used for circulation.

Large boulders, rock masses, etc. in the cut down earth and sand are floated up by the water flow and deposited in the drilling bucket 2.

When the drilling bucket 2 is filled with boulders, etc., the rotation is stopped, the opening (intake port) at the bottom of the drilling bucket is closed, the circulating water flow is stopped, and the cutting edge of the drilling tool 4 is reduced, as shown in Fig. 2. As shown, the drilling bucket 2 is pulled up from inside the casing 1, and cobbles and the like are discharged on the ground.

As described above, the earth and sand are cut down by the enlarged excavation blade 4 below the lower end of the casing 1,
Following the lowering of the excavating blade 4, the casing 1 sinks almost by its own weight.

As the drilling depth increases, the casing 1 becomes the joint 1.
The rotating rod 3 is also added to the upper part by the joint 3a in the same way.

The hole is drilled to the required depth as described above, but according to this method, the casing prevents the collapse of the earth and sand, so there is no need to use bentonite slurry, and the frictional resistance between the outer surface of the casing and the hole wall is small. It is extremely easy to insert and pull out the casing.

(Structure of the Invention) The bucket-type excavator according to the present invention can be used to carry out the above-mentioned excavation method, and has a discharge port on the top surface and an opening on the bottom surface, and is equipped with a digging cutter on the outer periphery of the bottom. The shutter consists of a drilling bucket, a flexible shutter for opening and closing the opening of the drilling bucket, and a telescopic opening/closing mechanism using a fluid pressure cylinder for opening and closing the shutter. The shutter is movably supported via a shutter guide extending from the bottom surface to the inner surface thereof, and is characterized in that the opening/closing operation mechanism and the shutter, which are housed inside the drilling bucket, are interconnected.

(Description of Embodiments) Hereinafter, details of the configuration of the present invention will be described based on embodiments shown in the drawings.

3, 4, and 5 show an embodiment of the bucket excavator of the present invention, in which FIG. 3 is a front longitudinal sectional view, FIG. 4 is a side longitudinal sectional view, and FIG. is a sectional view taken along line AA in FIG. 3;

Reference numeral 2 denotes a drilling bucket, which has a discharge port 2a on the upper surface connected to the rotary rod 3, and a cutter mounting plate 2b provided with the drilling cutter 4 on the lower surface.

A rectangular intake opening 5 is provided at the bottom of the hole-drilling bucket 2.

6 is a shutter guide having two rows of grooves parallel to each other.

The shutter guide 6 is composed of a horizontal portion 6a along the opening 5, an arcuate portion 6b rising continuously from the horizontal portion 6a, and a vertical portion 6c continuing from the upper end of the arcuate portion 6b.

7 is a shutter, which is constructed by combining a number of slats formed from band-shaped metal plates.
It is of a known structure similar to that generally used as a building material for warehouses, garages, stores, etc.

Both side edges of the slat of the shutter 7 are slidably supported by the shutter guide 6. 8
is an opening/closing operation mechanism consisting of a hydraulic or pneumatic fluid pressure cylinder, to which a drive source is connected via a piping system (not shown).

As shown in the figure, the opening/closing operation mechanism 8 is connected to a drilling bucket 2.
The axial direction is arranged perpendicularly on one side of the inside.

9 is a rod that is fitted into the cylinder of the opening/closing operation mechanism 8 and moves up and down, the tip of which is attached to the slat at the top end of the shutter 7;
The shutter 7 is pulled up and down by its vertical movement.

As described above, the bucket type excavator of the present invention is equipped with a shutter 7 facing the opening 5 of the excavating bucket 2, and is configured to be opened and closed by the shutter guide 6 and the opening/closing operation mechanism 8. .

In the above-described excavation method, when pulling up the drilling bucket 2, which is filled with large boulders, etc., the opening 5 is opened by activating the opening/closing operation mechanism 8 and pushing down the shutter 7 along the shutter guide 6. will be closed.

FIG. 3 shows a state in the middle of closing, and the shutter 7 moves in the direction of arrow A.

When opening the opening 5 to take in earth and sand at the start of excavation, the rod 9 can be operated upward in the opposite manner to the above, and the shutter 7 can be pulled up.

(Effects of the Invention) As described above, the bucket-type excavator of the present invention allows soil to be taken into the bucket of the excavation hole and transferred to the soil discharge side by keeping the opening open during excavation. Large grains of boulders, etc. can be taken in until the inside of the drilling bucket is filled, and after the bucket is filled, the opening can be closed with a shutter and the work of discharging the boulders, etc. can be carried out rationally. .

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams of the excavation method to which the present invention is applied, FIG. 3 is a front vertical cross-sectional view of one embodiment of the bucket-type excavator of the present invention, and FIG. 4 is a side vertical cross-sectional view thereof. FIG. 5 is a sectional view taken along line AA in FIG. 3. 2...Drilling bucket, 2a...Discharge port, 4...Drilling tool, 5...Opening part, 6...Shutter guide, 7...Shutter, 8...Opening/closing operation mechanism.

Claims (1)

[Claims] 1. A drilling bucket having a discharge port on the top surface, an opening on the bottom surface, and a drilling cutter on the outer periphery of the bottom, a bendable shutter for opening and closing the opening of the drilling bucket, and the shutter. It consists of a telescopic opening/closing operation mechanism using a hydraulic cylinder for opening and closing, and the shutter is movably supported via a shutter guide that extends from the bottom of the drilling bucket to its inner surface, and is installed inside the drilling bucket. A bucket-type excavator, characterized in that the above-mentioned opening/closing operation mechanism and a shutter are interconnected.