JPS5938394B2 - Auger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to an auger that can continuously excavate even if the excavated ground contains hard strata or rock, or even if cobbles or boulders are included.

Conventional augers are known to have spiral blades around the entire length of the auger shaft, or to have an auger head loosely attached to the tip of the auger shaft.
When using either.

After rotary excavation, the soil and sand packed between the helical blades in a consolidated state is discharged by pulling up the auger and buried again in the ground, and then the intermittent excavation method of rotary excavation has to be adopted, which reduces work efficiency. It was bad.

Moreover, since the excavated earth and sand are discharged to the ground, the work site becomes dirty and soil removal is required.

In addition, there may be hard strata or boulders in the excavated ground.

If boulders were included, the auger head would not be able to cut them, so the excavation had to be stopped when it hit the boulders.

If further excavation work is to be carried out, it is necessary to remove the auger from the hole, insert and reset the auger with a cutter head attached to the tip of the shaft, and then cut and drill the hole.

In the end, there was a drawback in that drilling required an extremely large amount of time, including the time required to change the auger and cutter head.

The present invention was devised to solve all of the problems of the conventional technology at once. gravel etc. (hereinafter referred to as excavated soil).

) is sufficiently stirred and kneaded with bentonite liquid, etc., and this kneaded material is applied to the hole wall and pressed in. A loam layer and a sand layer are formed by two-stage consolidation.

It is possible to reliably consolidate the hole wall close to the consolidation limit of each layer such as the gravel layer, thus greatly improving construction efficiency and construction quality compared to conventional methods, and also making it possible to eliminate soil removal altogether. The purpose is to provide an auger that can be used for various purposes.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The auger according to the present invention will be described below with reference to embodiments.

The auger shaft 1 is a stepped shaft with a proximal end 8 having a diameter close to the hole diameter of a cutter head 10 (described later), and around the shaft tip 2.

Agitator blades 4, 4' are provided that project radially from the shaft surface at the tip and base ends of the consolidation blade 3, which is separated from the shaft circumferential surface and curved along the circumferential direction.

The compression blades 3 may be continuous in the circumferential direction of the shaft, or may be spaced apart in this direction (as shown in the figure).

In this installation, a spiral blade 5 is used, which is provided around the shaft with the tip end of the shaft being the screwing direction.

The stirring blades 4, 4' are, for example, spaced apart from each other in the longitudinal direction of the shaft and in the circumferential direction, and do not match in the circumferential direction, but are alternately oriented in opposite directions, and the spiral blades 5 are also used for their installation. ing.

In other words, the helical blades 5 are cut off on both sides of the shaft 1 to provide blade pieces 6, and the blade pieces 7 with opposite directions are provided between adjacent helical blade parts on the both sides.

These blade pieces 6 and 7 constitute stirring blades 4 and 4'.

A spiral blade 9 is provided around the base end portion 8 of the shaft, with the direction of screwing in toward the tip end of the shaft.

The tip of the auger shaft 1 is the cutter head 1.
0 is attached.

Then, as a whole, a consolidation tool 3. Stirring blade 4.4',
The spiral blades 9 are in sliding contact and the curved surfaces of the shaft base end portion 8 are arranged to be close to each other with a gap of, for example, 100 mm.

However, the length of the stirring blades (4°4/) may be short as long as it has the effect of stirring and kneading the excavated earth and sand.

Further, it is sufficient that the compaction tool 3 and the stirring blade 4 form a pair, and the stirring blade 4' only facilitates the entry of contaminants into the gap 11 between the hole wall and the circumferential surface of the shaft, and is not necessarily required. Good too.

In the above configuration, when the auger shaft 1 is pressed into the ground while rotating, the cutter head 10 at the tip of the shaft
In the case of ground mixed with cobblestones or boulders, the cobblestones are cut, and in the case of rock, it is cut and drilled continuously.

Cutter head 10) When bentonite liquid is injected during such drilling, the stirring blades 4 first stir and knead the bentonite liquid and the excavated soil, and then the compaction tool 3 coats this kneaded material on the hole wall. Then, the first-stage hole wall consolidation is performed, and the kneaded material still remaining inside the hole is stirred and kneaded by the noble stirring blade 4' again, and then the helical blade 9 of the shaft base end 8 is used to mix the mixture between the hole wall and the shaft circumferential surface. The mixed material is introduced into the gap 11 between the two and pressed against the hole wall by the circumferential surface of the soyaft, thereby forcing the cut gravel, etc. in the kneaded material into the hole wall in a consolidated state, thereby performing the second stage of hole wall consolidation. .

Therefore, by using the auger of the present invention, while consolidating the hole wall in two stages and preventing its collapse, it is possible to continuously perform linear drilling using the hole wall as a guide using the 3° spiral blade 9 of the compaction tool.
The efficiency of excavation work can be significantly improved compared to the conventional auger method (intermittent excavation method).

Rather than cutting boulders, etc., they can be effectively used as gravel, etc., which is effective for the second stage of hole wall compaction.

In particular, the void ratio is approximately 60 to 70% in loam layers, approximately 35 to 45% in sand layers, and approximately 25 to 35% in gravel layers.
According to the auger of the present invention, the hole wall can be consolidated close to the consolidation limit of each layer.

Furthermore, since the excavated soil is effectively used to compact the hole wall as described above, it is not discharged at all (or even if it is discharged, only a small amount is required), and the work site can be cleaned accordingly.

Furthermore, since the hole walls can be compacted, only a small amount of bentonite solution is needed, and in some cases it is possible to use spring water without using bentonite solution.

As described above, the auger according to the invention organically combines each component so that each step of the auger method, from cutting and drilling to hole wall compaction, can be carried out reliably and smoothly. When used, the above-mentioned effects can be reliably obtained.

Also, since the base end of the shaft is enlarged, it can ensure sufficient strength to support the cutter head.

In addition to the cutter head, this auger shut has spiral blades,
Since it has a simple configuration that only includes a compaction tool and a stirring blade, it is easy to manufacture and maintain.

[Brief explanation of the drawing]

The drawing is a front view illustrating an auger according to the present invention in a construction state, with the tip of the cutter head omitted. 1... Auger shaft, 2... Shaft tip, 3... Consolidation tool, 4, 4'...
... Stirring blade, 5... Spiral blade, 6,7...
- Wing piece, 8... Soyaft base end. 9... Spiral wing, 10... Cutter head.

Claims (1)

[Claims] 1 The auger shaft is a stepped shaft whose base end is enlarged to a diameter close to the drilling diameter, and around the base end of the shaft, a spiral blade is provided with the shaft tip side being the threading direction, and the shaft A consolidation blade is provided around the tip portion, and is curved along the circumferential direction away from the shaft circumferential surface, and an agitation blade that projects radially from the shaft circumferential surface on the shaft tip side of the consolidation blade, and the auger shaft tip The auger is characterized by being equipped with a cutter head.