JP2008144561A - Earth auger head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an earth auger head suitable for an excavating work to remove piles and underground structures and an excavating work of base rock. <P>SOLUTION: An earth auger head 1 is constituted of a head main body provided with a spiral screw 4 and a center blade 5, an intermediate blade and an external blade 7 are arranged as excavating blade at an excavating end of the head body. The center blade is constituted of a rotatable conical bit, the intermediate blade is constituted of the conical bit in the same manner as the center blade, and a front blade 6a and a back blade 6b are parallely arranged based on a rotating direction of excavation. The back blade is bigger than the front blade and a leading volume δ(mm) is set in a range of 0<δ≤60 based on an axial direction of excavation. The external blade of the head for base rock is a rotatable conical bit, and a channel pipe having an injection hole is arranged in the front blade and the back blade having the leading volume δ. An excavation chip is cooled down by water supply from the injection hole, an excavation efficiency is increased and an excavation life is prolonged. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an earth auger head suitable for excavation work for removing existing piles and underground structures, and excavation work for drilling rocks and the like, and in particular, by improving the arrangement and configuration of excavation blades, It belongs to the field of excavation technology that has realized improvement, reduced wear damage of the excavating blade, and shortened exchanging time of the excavating blade.

Conventionally, since this type of earth auger head has been mainly subjected to excavation of earth and sand, a large number of excavation blades with conical bits attached are employed (for example, Patent Document 1 and Patent Document). 2).
On the other hand, in recent years, aging of buildings and building equipment has progressed, so the number of rebuilding works has increased. In this rebuilding work, existing piles and underground structures have been removed to make more land. There is a need for excavation work.
Conventional earth auger heads are also used at the site of this removal work and the site of drilling work such as bedrock.
However, in the removal work of existing piles and underground structures, a myriad of reinforcing bars are included in the concrete, and these reinforcing bars are strong due to the structure of the underground structures and the like. In addition, in drilling work such as bedrock, since the strength is high, the biting of the excavation tip is bad, and as a result, the excavation efficiency is not improved.
Therefore, the conventional removal work of underground structures and the like has a problem that the reinforcing bars in the concrete are entangled with the excavating blade in an extended state without being cut and the excavating blade is damaged in a short time. In addition, conventional excavation work such as bedrock has problems that excavation efficiency is poor and uneven wear tends to occur.
Japanese Patent Publication No. 47-2401 Utility Model Registration No. 3068462

The problem to be solved is that even if the removal work of existing piles and underground structures is the target, the reinforcing bars existing in the concrete are not tangled and cut to an appropriate length, and the excavation blade is missing, etc. It is an object of the present invention to provide an earth auger head having an improved configuration and arrangement of excavation blades so as to prevent a decrease in excavation performance due to the above.
Another object of the present invention is to provide an earth auger head improved in excavation work such as bedrock, in which the excavation tip is easily bitten, the excavation efficiency is improved, and uneven wear does not occur.

  The earth auger head according to claim 1 of the present invention is provided with a spiral screw composed of two or three wings in the axial direction of the head body, and at the excavation end side, a head as an excavation blade. In the earth auger head in which the central blade, the intermediate blade, and the outer blade are radially arranged from the shaft end of the main body toward the outer edge of the screw, the central blade is a rotation that is disposed near the axial center of the head main body. The intermediate blade is composed of a plurality of conical bits that can rotate in two rows so as to be a front blade and a rear blade when the rotation direction is a reference. The rear blade is larger than the front blade and is positioned so as to have a leading amount δ with respect to the front blade when the axial direction of excavation is used as a reference, Side blade is auger head, characterized in that it has to be constituted by one or more rotating non replaceable bits.

According to the above configuration, the earth auger head is provided with the central blade, the intermediate blade, and the outer blade as the excavating blades, respectively, so that it is appropriate in the portion from the vicinity of the axial center of the head body to the outer edge of the screw. Excavation work.
That is, the central blade is located near the axis center of the head body, excavates at a low speed while rotating and revolving, and prevents uneven wear during excavation from the rotation action.
Similarly, the intermediate blade that rotates and revolves has a positional relationship in which the front blade and the rear blade have a leading amount δ in the axial direction of excavation and is larger than the front blade, thereby enabling stable excavation. In this case, the front blade excavates the reinforcing bar in the concrete, and the extended reinforcing bar is cut to an appropriate length by the rear blade.
Furthermore, since the outer blade is configured to not rotate and is positioned on the high speed side, it performs an excavating function as a wiper blade.
In the case of a 2-wing earth auger head, the amount of rebar is applied to normal construction sites because of the feed per blade, and in the case of a 3-wing earth auger head, the amount of rebar is large and the rebar is frequently cut. Applied.

The earth auger head according to claim 2, wherein the outer blade is constituted by a conical bit capable of rotating.
According to the above configuration, in the above-described removal work of the underground structure or the like, the casing blade on the end face of the rotating casing can be provided by positioning the rotating casing provided in the excavating machine outside the outer peripheral portion of the earth auger head. Since a part of the reinforcing bar is supported, the rear blade of the intermediate blade can be cut without tangling the reinforcing bar.

The earth auger head according to claim 3, wherein a leading amount δ (mm) of the rear blade is set to 0 <δ ≦ 60. is there.
According to the above configuration, since the leading amount δ can be selected depending on the amount of reinforcing bars, a good excavation state can be ensured according to the situation of the excavation site of the removal work.

The earth auger head according to claim 4 is provided with a spiral screw composed of two or three blades in the axial direction of the head main body, and at the excavation end side as an excavation blade, the axial end of the head main body. In the earth auger head in which the central blade, the intermediate blade, and the outer blade are radially arranged from the outer edge of the screw to the outer edge of the screw, the central blade has a plurality of rotatable wheels arranged near the axis center of the head body. The intermediate blade is composed of a plurality of conical bits that can rotate in two rows so as to be a front blade and a rear blade when the rotation direction is a reference, and the rear blade. Is larger than the front blade and has a leading amount δ with respect to the front blade when the axial direction of excavation is used as a reference. Is constituted by two or more conical bits that can rotate, and a water channel pipe branched from the head body is arranged between the front blade and the rear blade of the intermediate blade, and the excavation tip is cooled by water supply from the injection hole It is the earth auger head characterized by having made it.
According to the above configuration, the rear blade having the leading amount δ starts biting and excavation before the front blade, so that stable excavation is possible and the excavation tip is cooled by the water channel pipe having the injection hole. Therefore, it can be applied to excavation of bedrock.

5. The earth auger bit according to claim 1, wherein a leading amount δ (mm) of the rear blade is set to 0 <δ ≦ 60. is there.
According to the above configuration, since the leading amount δ can be selected depending on the hardness of the rock mass, a favorable excavation state can be ensured according to the situation of the excavation site of the drilling work such as the rock mass.

The earth auger head according to the present invention is suitable for the removal of existing piles and underground structures where reinforcing bars exist in the concrete by using intermediate blades consisting of a front blade and a rear blade in a specific relationship. Since it is cut to length, good excavation can be performed.
As a result, breakage of the excavation blade due to the entanglement of the reinforcing bars is reduced, and the central blade and the intermediate blade are conical bits that can rotate, thereby preventing uneven wear. In addition, because the outer blade uses a replaceable bit that does not rotate, it can be easily replaced even if it is damaged or worn. It has the advantage of being able to.
Further, the earth auger head according to the present invention can be constituted by a conical bit capable of rotating the outer blade. In this case, a rotating casing arranged in an excavator may be used for the removal work of existing piles and underground structures where reinforcing bars exist in the concrete. In other words, since the rebar is partially supported by the casing blade formed on the end face of the rotating casing, the rebar is cut without being entangled by the rear blade.
Furthermore, the ground auger head according to the present invention can be set in a range of 0 <δ ≦ 60, so that the leading amount δ (mm) of the rear blade is good depending on the excavation site of the removal work such as an underground structure. The excavation state can be secured.
Further, the earth auger head according to the present invention stabilizes excavation work by biting the rear blade having a leading amount δ in excavation work such as bedrock and has an injection opening between the front blade and the rear blade. Further, since the excavation tip provided in the excavation blade is cooled by the arrangement of the water channel pipe, there is an advantage that the excavation efficiency is improved and the life can be extended. In this case, since the leading amount δ (mm) of the rear blade can be set within a range of 0 <δ ≦ 60, a good excavation state can be ensured according to the excavation site of drilling work such as a rock mass.

Hereinafter, an earth auger head according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a conceptual front view showing an earth auger head according to a first embodiment of the present invention, and FIG. 2 is a bottom view conceptually showing an arrangement state of excavation blades.
The earth auger head 1 of the first embodiment has a rotatable head body 3 having a fixed shaft portion 2 attached to an unillustrated excavator, and the head body 3 has a spiral shape, for example, 2 in the axial direction. A screw 4 comprising wings is provided. As shown in FIG. 2, a central blade 5, an intermediate blade 6, and an outer blade 7 are arranged on the digging end side of the head body 3 as digging blades.

The central blade 5 is constituted by a plurality of conical bits that can rotate, and in the illustrated case, the mounting head 8 is provided with a total of four conical bits 5a and 5b having a size relationship. It has become. In this case, the mounting head 8 is mounted by, for example, providing a screw portion (not shown) on the mounting shaft side and screwing this screw portion into a screw hole (not shown) provided in the head body 3. .
The conical bits 5a and 5b have a drilling tip 9 made of cemented carbide attached to the tip thereof by brazing, press fitting, or the like, and the rear end side thereof is supported, for example, as shown in FIG. In the mounting hole 11 of the block 10, it is rotatably mounted by a support ring 12. The conical bits 5a and 5b are excavated while rotating and revolving, and accordingly, uneven wear is prevented.
FIG. 3 is a front view of the conical bits 5 a and 5 b attached to the support block 10 welded to the mounting head 8, partly in cross section.
4 is an explanatory view from the bottom direction illustrating the mounting head 8. FIG. 4 (a) shows the four conical bits 5a and 5b having the above-described magnitude relationship arranged in the circumferential direction. FIG. 4 (b) shows an arrangement in which diametrically aligned rows of equal size are arranged. These are appropriately selected according to the excavation situation.

The intermediate blade 6 is constituted by a plurality of conical bits that can rotate in the same manner as the central blade 5. As clearly shown in FIG. 5, these conical bits are rotatably mounted by a support ring 15 on the rear end side in the mounting hole 14 of the support block 13 and positioned on the opening side of the mounting hole 14. The
The support block 13 is attached to the screw end face on the excavation end side of the head body 3 by welding.
The intermediate blades 6 are arranged in two rows so as to be the front blades 6a and the rear blades 6b when the rotation direction of excavation is used as a reference, and the rear blades 6b are larger than the front blades 6a and are excavated. With respect to the axial direction, the front blade 6a is positioned so as to have a leading amount δ.
The reason for this is that the intermediate blade 6 can cope with the reinforcing bars in the removal work of existing piles and underground structures. In other words, these piles and underground structures have reinforcing bars in the concrete from the viewpoint of strength, so the conventional earth auger head entangled with the drilling blade in a state where the reinforcing bars were stretched without being cut. The blade was damaged or lost.
On the other hand, in the earth auger head 1 according to the present invention, the plurality of front blades 6a excavate the reinforcing bars, and the reinforcing bars extending thereby are cut by the rear blades 6b to an appropriate length. As a result, it is possible to improve excavation efficiency and extend the tool life by preventing the cutting blade from being damaged.
The leading amount δ (mm) is set within a range of 0 <δ ≦ 60, although it varies depending on excavation conditions. The leading amount δ is 0 or less in the case of a conventional earth auger head, and if it exceeds 60 mm, the step of excavation becomes large and the function of cutting the reinforcing bar by the rear blade 6b cannot be fully utilized.

For example, as illustrated in FIG. 6, the outer blade 7 is configured by a replaceable bit that does not rotate, and has a function as a blade for the excavation surface.
For example, the outer blade 7 is attached to the support holder 16 shown in FIG. FIG. 6 is an explanatory view illustrating a replaceable bit. FIG. 6A is a front view, and FIG. 6B is a plan view. FIG. 7 is an explanatory view of a support holder to which a replaceable bit is attached. FIG. 7 (a) is a front view, FIG. 7 (b) is a plan view, and FIG. 7 (c) is a left side view. It is.
6 and 7, the outer blade 7 and the support holder 16 are formed with a U-shaped attachment groove 19 on the rear end side of the bit body 18, and the attachment groove 19 is used as a protruding portion 20 of the support holder 16. After fitting, the mounting bolt 17 is used. The excavation tip 21 made of a cemented carbide brazed to the tip of the outer blade 7 is formed with V-shaped projections on the rake face side and the flank face side of the excavation in order to increase the strength. Yes.
In addition, in order to prevent the bit body 18 from being worn around the excavation tip 20, as shown by a two-dot chain line, a build-up 22 made of a metal hardened layer is covered. Note that the outer blade 7 is not limited to the configuration with respect to the support holder 16 described above, and attachment means having other configurations can also be employed.
Further, FIG. 8 is a bottom view conceptually showing the arrangement state of the excavating blades for the earth auger head provided with the screw 4 composed of three blades. In FIG. 8, the central blade 5, the intermediate blade 6, and the outer blade 7 are respectively disposed at the excavation end of the head body 3. This reduces the load for cutting the reinforcing bars by reducing the feed amount per blade even with the same excavation diameter.

As described above, the earth auger head 1 configured as described above has the central blade 5, the intermediate blade 6, and the outer blade 7 disposed at the excavation end of the head body 3.
FIG. 9 is a conceptual explanatory diagram showing the excavation state by the excavation blade with a single blade. And Fig.9 (a) has shown the excavation state by the center blade 5. FIG.
FIG. 9B shows a state where the front blade 6a and the rear blade 6b are excavated as the intermediate blade 6, and the rear blade 6b has a leading amount δ with respect to the front blade 6a. The leading amount δ is present because the excavation tip 9 of the front blade 6a excavates the reinforcing bar in the concrete, and the excavation tip 9 of the rear blade 6b cuts the reinforcing bar extended along with the excavation to an appropriate length. It is consideration.
Further, FIG. 9C shows a state of excavation by the outer blade 7, and in a normal case, it has a function as a wiping blade.

In addition, about the earth auger head 1 which concerns on this invention, it is also possible to change the arrangement | positioning state of the center blade 5, the intermediate blade 6, and the outer blade 7. FIG.
FIG. 10 is a bottom view conceptually showing the state of arrangement of the excavating blades, and the central blade 5 is the same as in FIG. 2, but the number of intermediate blades 6 and outer blades 7 is small, and is used for small diameters. It can be seen that this is applied. Other configurations are the same as in FIG.
Further, FIG. 11 is a bottom view conceptually showing the arrangement state, and the number of intermediate blades 6 and outer blades 7 is larger than that in FIG. I understand. Other configurations are the same as in FIG.

<Excavation example>
As shown in FIG. 1 and FIG. 2, the earth auger head 1 has two blades 4 and a drilling blade is attached to the excavation end as follows, and the excavation diameter = φ1200 mm, the rear blade The leading amount δ of 6b was set to be 10 mm.
The central blade 5 has two medium conical bits 5a and 5b of equal size, and the intermediate blade 6 has 3 × 2 front blades 6a made of medium conical bits and 3 × 2 rear blades 6b made of large conical bits. For the blade 7, 2 × 2 replaceable bits were applied.
The excavating machine is a separate auger, and the excavation work is the removal work of the existing reinforced concrete drainage channel. This spillway was built about 40 years ago. According to the design drawing, the reinforcing bars in the concrete are arranged with vertical bars of φ25 mm × 200 to 250 pitch and horizontal bars of φ25 mm and φ19 mm alternately arranged. Is.
In excavation by the earth auger head 1 according to the present invention, the rebar was cut to 100 to 300 mm, and excavation resistance was small and good. In this case, the excavation speed was 1.2 m / hour, and 15 m excavation was possible.
The excavating blades were not damaged for the six rear blades 6b and could be used continuously. However, some of the central blades 5a, 5b and the front blades 6a had small defects. It was seen. As for the outer blade 7, it was found that the excavation tip was normally worn and it was time to replace it.
In addition, although the earth auger head 1 which concerns on this invention continued excavation after replacing | exchanging the said outer blade 7, excavation of 6-7m was possible.
On the other hand, the conventional type earth auger head incorporating only a conical bit has an excavation speed of 1 m / hour, but the rebar is stuck and the excavation resistance is large. It became impossible.
Note that the leading amount δ (mm) of the rear blade 6b was increased to 40 mm, 50 mm, and 60 mm and performed using another excavation test. However, the above-described range of 0 <δ ≦ 60 is effective. It was confirmed.

  When the excavating machine is equipped with a rotating casing, the rotating casing is positioned on the outer peripheral side of the earth auger head 1. As a result, since the casing blade formed on the end surface of the rotating casing supports a part of the reinforcing bar, the outer blade 7 also functions to cut the reinforcing bar.

Next, a second embodiment of the earth auger head 1 according to the present invention will be described. The same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof will be omitted or simplified. In this case, the earth auger head 1 of the second embodiment is adopted based on the knowledge of the excavation result using the rotating casing described above, and FIG. 12 shows the second embodiment of the earth auger head according to the present invention. It is the bottom view which showed notionally the arrangement | positioning state of the excavation blade in a form.
If the earth auger head 1 which concerns on 2nd Embodiment is demonstrated with reference to FIG. 12, the center blade 5, the intermediate blade 6, and the outer blade 7 which consist of a conical bit will be arrange | positioned at the excavation end of the head main body 3, respectively. ing.
The intermediate blade 6 is composed of a small conical bit 6a and a large conical bit 6b, and the outer blade 7 is composed of two medium conical bits.
The earth auger head 1 having such a configuration was applied to the removal work of an underground structure or the like by using a rotating casing equipped in the excavating machine. As a result, the casing blade of the rotary casing supported a part of the reinforcing bar, and the reinforcing bar could be cut by the rear blade 6b and the outer blade 7.

Furthermore, although 3rd Embodiment of the earth auger head 1 which concerns on this invention is described, the same code | symbol is attached | subjected to the components similar to 1st Embodiment, and description is abbreviate | omitted or simplified. FIG. 13 is a conceptual front view showing an earth auger head according to a third embodiment of the present invention, and FIG. 14 is a bottom view conceptually showing an arrangement state of excavation blades.
If the earth auger head 1 which concerns on 3rd Embodiment is demonstrated with reference to FIG.13 and FIG.14, at the excavation end of the head main body 3, the central blade 5 which consists of a conical bit similarly to FIG. The outer blades 7 are arranged respectively.
The earth singer head 1 of the third embodiment is intended to be applied to excavation work such as bedrock, and the excavation work is stabilized by the biting of the rear blade 6b having the leading amount δ.
Further, between the front blade 6 a and the rear blade 6 b of the intermediate blade 6, a water channel pipe 31 branched from a water guide pipe 30 provided in the head body 3 is disposed, and the excavation tip 9 is supplied by water supply from the injection hole 32. Is cooled. Therefore, even in rock excavation work, the excavation efficiency is improved and the life can be extended.
The leading amount δ (mm) of the rear blade 6b described above is set in a range of 0 <δ ≦ 60, although it varies depending on the excavation state. The leading amount δ is 0 or less in the case of the conventional earth auger head, and if it exceeds 60 mm, the level difference of excavation becomes large and the situation becomes unstable.
Moreover, although the case where the screw 4 is 2 blades is shown, the case of 3 blades is also possible. With three wings, even if the excavation diameter is the same, the feed amount per blade is small, and the bite against the rock is increased, so that stable excavation is possible.
Other configurations are the same as those in FIGS. 1, 2, and 12, and are common.

  1 is a conceptual front view showing an earth auger head according to a first embodiment of the present invention.   It is a bottom view with respect to FIG. 1 which shows the arrangement | positioning state of a digging blade notionally.   It is the front view which partially illustrated the mounting state about the center blade with which the support block of the mounting head was mounted | worn.   4A and 4B are explanatory views from the end face direction of the mounting head. FIG. 4A is a bottom view in which four conical bits are arranged in the circumferential direction, and FIG. It is the bottom view arranged individually.   It is a front view which shows the state with which the conical bit applied as an intermediate blade was mounted | worn to the support block.   It is explanatory drawing which shows notionally the exchangeable bit applied as an outer blade, FIG. 6 (a) is a front view, FIG.6 (b) is a top view.   It is explanatory drawing of the support holder which attaches a replaceable bit, Fig.7 (a) is a front view, FIG.7 (b) is a top view, FIG.7 (c) is a left view.   It is a bottom view which shows notionally the arrangement state of the excavation blade in a 3 blade screw.   It is explanatory drawing which shows notionally the excavation state of an excavation blade as a single blade, FIG.9 (a) is the side view which showed the excavation state by a center blade, FIG.9 (b) is a front blade and a back blade. FIG. 9C is a side view showing the leading positional relationship, and FIG. 9C is a side view showing the excavation state by the outer blade.   It is a bottom view which shows notionally the modification of the arrangement | positioning state of a digging blade.   It is a bottom view which shows notionally other modifications of the arrangement state of a digging blade.   It is the bottom view which showed notionally the arrangement | positioning state of a digging blade about 2nd Embodiment of the earth auger head which concerns on this invention.   It is a notional front view showing an earth auger head concerning a 3rd embodiment of the present invention.   It is a bottom view with respect to FIG. 13 which shows the arrangement | positioning state of a digging blade notionally.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Earth auger head 2 Fixed shaft part 3 Head main body 4 Screw 5 Center blade 5a, 5b Conical bit 6 Intermediate blade 6a Front blade 6b Rear blade 7 Outer blade 8 Mounting head 9 Excavation tip 10, 13 Support block 11, 14 Mounting hole 12 , 15 Support ring 16 Support holder 17 Mounting bolt 18 Bit body 19 Mounting groove 20 Projection portion 21 Excavation tip 22 Overlay 30 Water guide pipe 31 Water pipe 32 Injection hole

Claims (5)

In the axial direction of the head main body, a spiral screw consisting of two or three wings is provided, and on the excavation end side, as a excavating blade, a central blade from the axial end of the head main body toward the outer edge of the screw, In the earth auger head in which the intermediate blade and the outer blade are arranged radially,
The central blade is composed of a plurality of conical bits that can be rotated around the axis of the head body,
The intermediate blade is composed of a plurality of conical bits that can rotate in two rows, which are a front blade and a rear blade, with respect to the rotational direction of excavation, and the rear blade is more than the front blade. It is large and is positioned so as to have a leading amount δ with respect to the front blade when the axial direction of excavation is used as a reference,
2. The earth auger head according to claim 1, wherein the outer blade is composed of one or more interchangeable bits that do not rotate.   2. The earth auger head according to claim 1, wherein the outer blade is constituted by a conical bit capable of rotating.   3. The earth auger head according to claim 1, wherein a leading amount δ (mm) of the rear blade is set to 0 <δ ≦ 60. In the axial direction of the head main body, a spiral screw consisting of two or three wings is provided, and on the excavation end side, as a excavating blade, a central blade from the axial end of the head main body toward the outer edge of the screw, In the earth auger head in which the intermediate blade and the outer blade are arranged radially,
The central blade is composed of a plurality of conical bits that can be rotated around the axis of the head body,
The intermediate blade is composed of a plurality of conical bits that can rotate in two rows, which are a front blade and a rear blade, with respect to the rotational direction of excavation, and the rear blade is more than the front blade. It is large and is positioned so as to have a leading amount δ with respect to the front blade when the axial direction of excavation is used as a reference,
The outer blade is composed of one or more conical bits that can rotate,
An earth auger head characterized in that a water channel pipe branched from the head main body is arranged between the front blade and the rear blade of the intermediate blade, and the excavation tip is cooled by water supply from the injection hole.   The earth auger head according to claim 4, wherein a leading amount δ (mm) of the rear blade is set to 0 <δ ≦ 60.

Images