JP2010185188A - Drilling bucket - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drilling bucket which enables high-quality construction to be performed without being affected by the conditions of natural ground. <P>SOLUTION: This drilling bucket 1 includes a cylindrically-formed bucket body 10, and a bottom cover 20 arranged on the bottom of the bucket body 10. The bottom cover 20 includes a slit 22, a plurality of cutter bits 24 juxtaposed along the slit 22, and a plurality of cutter bits 25 juxtaposed in such a manner as to protrude downward along an edge. The center of the bottom cover 20 is formed higher than the edge. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a drilling bucket.

In the construction of cast-in-place concrete piles, excavation work may be performed by the earth drill method.
The earth drill method is an excavation method in which a drilling bucket is lowered while rotating to cut a natural ground and take excavated earth and sand into the bucket to form an excavation hole in the natural ground.

  As shown in FIG. 5, the drilling bucket 101 described in Patent Document 1 includes a cylindrical bucket body 110 and a bottom lid 120 attached to the lower end (bottom) of the bucket body.

  The bottom lid 120 of the drilling bucket 101 is formed in a conical shape protruding downward, and is attached to the bottom of the bucket body 110 so as to be openable and closable. In addition, the bottom lid 120 includes a cutting blade 121 and a slit formed along the cutting blade 121.

  The excavation work is performed by rotating the drilling bucket 101 to cut a natural ground with the cutting blade 121 and taking the cut earth and sand into the bucket body 110 from the slit.

JP-A-7-301077

  However, in the conventional drilling bucket 101, since the bottom lid 120 is formed in a tapered conical shape, a portion with different ground strength such as an existing pile pullout trace is included in the cross section of the excavation hole. In some cases, the excavation proceeds to the weaker ground strength, and the shaft of the excavation hole is shaken. When the shaft of the excavation hole fluctuates, it is necessary to take measures such as excavation again, which causes a problem of affecting the construction period and increasing the cost.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to propose a drilling bucket that enables high-quality construction without being affected by natural ground conditions.

  In order to solve such a problem, a drilling bucket according to a first aspect of the present invention includes a bucket body formed in a cylindrical shape, and a bottom lid disposed at a bottom portion of the bucket body, and the bottom lid includes a slit. And a plurality of cutter bits juxtaposed along the slit, and a plurality of cutter bits juxtaposed so as to protrude downward along the edge portion, the center portion of the bottom cover It is characterized by being formed so as to be higher than the edge portion.

  The drilling bucket according to the second aspect of the present invention includes a bucket body formed in a cylindrical shape and a bottom lid disposed at the bottom of the bucket body, and the bucket body has a lower end lower than the bottom lid. The bottom cover has a slit and a plurality of cutter bits juxtaposed along the slit, and a central portion. Is characterized by being formed to be higher than the edge portion.

  According to the drilling bucket of the present invention, since the bottom lid is recessed inside the bucket body, it is possible to perform cutting in a state in which the natural ground has entered the bottom of the drilling bucket. Therefore, it is possible to perform high-quality drilling in which shaft excursion of the drilling hole is suppressed by the excavation resistance of the natural ground in contact with the bottom cover.

  Further, the drilling bucket is a cylindrical auxiliary bucket connected to the upper portion of the bucket body, and includes an auxiliary bucket in which an opening is formed at a position corresponding to a joint portion between the bucket body and the kelly bar. May be. Moreover, you may equip the upper end part of this auxiliary bucket with the stabilizer.

  According to such a drilling bucket, it is possible to further suppress the shaft shake of the excavation hole, and it is possible to perform high-quality construction.

  According to the drilling bucket of this invention, it becomes possible to perform high quality construction, without being influenced by natural ground conditions.

It is the schematic which shows the use condition of the drilling bucket which concerns on suitable embodiment of this invention. It is a figure which shows the drilling bucket which concerns on 1st Embodiment, Comprising: (a) is a cross-sectional view, (b) is an AA arrow line view of Fig.2 (a). It is a figure which shows the action condition of the force at the time of excavation by a drilling bucket, Comprising: (a) is the drilling bucket which concerns on 1st Embodiment, (b) is the conventional drilling bucket. It is a figure which shows the drilling bucket which concerns on 2nd Embodiment, Comprising: (a) is a cross-sectional view, (b) is an AA arrow line view of Fig.4 (a). It is the schematic which shows the conventional drilling bucket.

DESCRIPTION OF EMBODIMENTS Preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals are used for the same elements, and duplicate descriptions are omitted.
Although this embodiment demonstrates the case where the drilling bucket of this invention is used at the time of the drilling of the excavation hole of a spot pile, the use purpose of a drilling bucket is not limited.

  As shown in FIG. 1, the drilling bucket 1 according to the first embodiment cuts the ground G while being suspended by a crane C that is a lifting machine, and is suspended by a wire W. The kelly bar K is fixed to the tip.

  As shown in FIG. 2, the drilling bucket 1 includes a cylindrical bucket body 10, a bottom cover 20 disposed at the bottom of the bucket body 10, and a cylindrical auxiliary connected to the top of the bucket body 10. Bucket 30.

  The bucket body 10 is formed of a cylindrical steel pipe. As shown in FIG. 2A, the upper part is fixed to the tip (lower end) of the kelly bar K, and the bottom lid 20 is installed at the lower end. Yes.

  At the upper end of the bucket body 10, a socket 11 for connecting to the kelly bar K is projected upward. The bucket body 10 is fixed to the kelly bar K by inserting a fixing pin 12 into the socket 11 and the kelly bar K with the lower end of the kelly bar K inserted into the socket 11. In the present embodiment, the socket 11 and the Kelly bar K are fixed by inserting the two fixing pins 12 in a cross shape from two directions. The method for fixing the bucket body 10 to the Kelly bar K is not limited.

  As shown in FIG. 2B, the bucket body 10 includes a trillion 15 for connecting the bottom lid 20 so that the bottom lid 20 can be opened and closed, and a locking member for locking the bottom lid 20 in a closed state. A portion corresponding to the bottom lid 20 at the lower end is provided. In the present embodiment, the trillion number 15 and the locking member 16 are formed at positions facing each other across the center of the bottom cover 20. The trillion number 15 is formed at the lower edge of the bucket body 10. Therefore, the bottom cover 20 is opened and closed by rotating around the edge of the bucket body 10.

Further, a side cutter 14 formed in a horizontal direction is disposed at the lower end of the bucket body 10.
The side cutter 14 cuts the natural ground G so that a gap is formed between the outer peripheral surface of the bucket body 10 and the hole wall by the rotation of the bucket body 10.

  As shown in FIG. 2A, the bottom cover 20 is made of a steel plate formed so that the center portion is higher than the edge portion. Although the material which comprises the bottom cover 20 is not limited to a steel plate, it needs to have sufficient proof strength with respect to the pressure and frictional force which act at the time of drilling the natural ground G.

  After the bottom lid 20 is inclined so as to become higher from the periphery toward the center, the center portion 21 is formed so that the center protrudes downward, so that the cross section is formed in an M shape. . The central portion 21 does not necessarily have to protrude downward. Further, the bottom cover 20 may be recessed in an arc shape (a bowl shape).

  As shown in FIG. 2B, the bottom lid 20 is formed with two slits 22 that open along the radial direction. The number and shape of the slits 22 are not limited. The bottom lid 20 is formed with a locking hole 23 at a location corresponding to the locking member 16 of the bucket body 10. Further, a trillion number 15 is connected to a portion facing the locking hole 23 across the center portion of the bottom cover 20.

  A plurality of slit bits (cutter bits) 24, 24,... Are juxtaposed along the edge of the slit 22.

  As shown in FIGS. 2A and 2B, the bottom cover 20 includes a plurality of cutter bits 25 disposed so as to protrude downward along the peripheral edge.

  As shown in FIG. 2B, the cutter bit 25 is disposed obliquely with respect to the circumferential direction of the bucket body 10 in plan view. The directions of adjacent cutter bits 25 are alternately changed. Note that the number, arrangement interval, orientation, shape, and the like of the cutter bits 25 are not limited.

The bottom lid 20 is installed on the bucket body 10 via a trillion number 15 so as to be freely opened and closed. During excavation, the locking member 16 is locked in the locking hole 23 to shield the lower end portion of the bucket body 10, and when the earth and sand are discharged after excavation, the locking state of the locking member 16 is released to lower the lower end portion. Is released.
The method for connecting the bucket body 10 and the bottom lid 20 is not limited. For example, in the present embodiment, the bottom lid 20 is locked by one locking member 16, but a plurality of locking members 16 may be arranged.

  The auxiliary bucket 30 is connected to the upper end of the bucket body 10 as shown in FIG. The auxiliary bucket 30 is formed of a steel pipe having the same outer shape as the bucket body 10.

An opening 31 is formed in the auxiliary bucket 30 at a location corresponding to the joint between the bucket body 10 and the kelly bar K.
A stabilizer 32 is provided at the upper end of the auxiliary bucket 30. As long as the stabilizer 32 can control the inclination of the drilling bucket 1, the shape and the like thereof are not limited.

  Next, a method for forming the excavation hole H by the drilling bucket 1 according to the first embodiment will be described.

  Cutting the natural ground G is performed by lowering the kelly bar K while rotating the kelly bar K after the drilling bucket 1 is installed at a predetermined place by the crane C (see FIG. 1).

The drilling bucket 1 rotates in synchronization with the rotation of the kelly bar K, and the natural ground G is cut by the slit bit 24, the cutter bit 25 and the side cutter 26.
Since the bottom cover 20 is recessed inside the bucket body 10, cutting is performed in a state in which the natural ground G enters the bottom of the drilling bucket 1 (see FIG. 2A).

  In the drilling bucket 1, the ground that has entered the bottom is taken into the bucket body 10 from the slit 22 while being cut by the slit bit 24.

  When a certain amount of earth and sand is accommodated in the bucket body 10, the drilling bucket 1 is once lifted to the ground. And after opening a bottom cover and discharging internal excavation earth and sand, excavation of a natural ground is performed again. Such an operation is repeated until the excavation hole H reaches a desired depth.

  As described above, according to the drilling bucket 1 according to the first embodiment, the cutting is performed in a state in which the natural ground G enters the bottom portion of the drilling bucket 1, so that excavation resistance due to the natural ground G acts on the bottom lid 20. . Therefore, the horizontal blur of the drilling bucket 1 is controlled by the excavation resistance of the natural ground G, and it becomes possible to perform high-quality construction in which the blur of the hole shaft is suppressed.

  Moreover, since the center part 21 of the bottom lid 20 protrudes downward in the drilling bucket 1, since this part is cut in a state where it is inserted into the natural ground G, the lateral blur is further controlled. Yes.

In addition, with excavation by the drilling bucket 1, a pressing force P1 by the drilling bucket 1 acts on the natural ground G through the bottom lid 20, as shown in FIG. The pressing force P <b> 1 acting on the natural ground G acts inward (in the direction of the rotation axis of the drilling bucket 1) depending on the shape of the bottom cover 20. Therefore, even if the soft ground G1 exists on the side of the natural ground G, the soft ground G1 side does not collapse due to the force acting on the inside, and the drilling bucket 1 is not shaken in the cutting direction. .
On the other hand, in the case of the conventional drilling bucket 101, as shown in FIG.3 (b), the pressing force P2 which acts on the natural ground G with the shape of the bottom cover 120 acts in the direction away from a center. Therefore, when the soft ground G1 exists in the side of the natural ground G, the soft ground G1 side may collapse | crumble by the pressing force P2, and the blurring of the cutting direction by the drilling bucket 101 may arise.

  Therefore, according to the drilling bucket 1, even if there is a portion with different strength (soft ground G1) in the cross section of the excavation hole H in the natural ground G, such as the site of an existing pile, the axis of the excavation hole H Blur is suppressed.

  Moreover, since the auxiliary bucket 30 is connected to the upper part of the bucket main body 10 in the drilling bucket 1, the resistance force with respect to the inclination of the drilling bucket 1 increases, and also the construction quality is improved.

Moreover, since the stabilizer 32 formed in the auxiliary bucket 30 further suppresses the inclination of the drilling bucket, high-quality construction is possible.
In addition, since the opening part 31 is formed in the auxiliary bucket 30, attachment / detachment of the drilling bucket 1 to the kelly bar K can be performed easily.

  Since the drilling bucket 1 is joined to the kelly bar K by inserting the two fixing pins 12 in a cross shape from different directions, rattling at the joint is suppressed.

  Since the side cutter 26 is disposed in the bucket body 10, a predetermined gap is formed between the hole wall of the excavation hole H and the drilling bucket 10, and the friction between the side surface of the drilling bucket 10 and the ground G Construction will not be hindered by resistance.

  Moreover, since the bottom part of the bucket main body 10 is open | released entirely by opening the bottom cover 20, it becomes possible to perform the discharge | emission work of excavated earth and sand more efficiently.

  As shown in FIG. 4, the drilling bucket 2 according to the second embodiment includes a bucket body 10 that is formed in a cylindrical shape, a bottom lid 20 that is disposed at the bottom of the bucket body 10, and an upper portion of the bucket body 10. And a cylindrical auxiliary bucket 30 connected to each other.

The bucket body 10 is formed of a cylindrical steel pipe. As shown in FIG. 4A, the upper part is fixed to the tip (lower end) of the kelly bar K, and the lower end is below the bottom cover 20. It protrudes.
The bucket body 10 rotates by rotating the kelly bar K, and cuts natural ground with the cutter bit 13 and the side cutter 14 disposed at the lower end.

  At the upper end of the bucket body 10, a socket 11 for connecting to the kelly bar K is projected upward. Note that the method for fixing the bucket body 10 to the kelly bar K is the same as that described in the first embodiment, and a detailed description thereof will be omitted.

  A plurality of cutter bits 13 and side cutters 14 are disposed at the lower end of the bucket body 10.

  The cutter bit 13 is disposed downward on the lower end surface of the bucket body 10. Further, as shown in FIG. 4B, the cutter bit 13 is disposed obliquely with respect to the circumferential direction of the bucket body 10 in a plan view, and has a width larger than the wall thickness of the bucket body 10. It is comprised so that a circular groove | channel can be cut.

  In the present embodiment, the directions of adjacent cutter bits 13 are alternately changed. In addition, the number of cutter bits 13, arrangement | positioning space | interval, direction, a shape dimension, etc. are not limited.

  The side cutter 14 is disposed sideways at the lower end of the bucket body 10. The side cutter 14 cuts the natural ground G so that a gap is formed between the outer peripheral surface of the bucket body 10 and the hole wall.

  As shown in FIG. 4B, the bucket body 10 includes a trillion 15 for connecting the bottom cover 20 so that the bottom cover 20 can be opened and closed, and a locking member 16 for locking the bottom cover 20 in a closed state. , Provided at a location corresponding to the bottom lid 20 at the lower end. In the present embodiment, the trillion number 15 and the locking member 16 are formed at positions facing each other across the center of the bottom cover 20.

  As shown in FIG. 4A, the bottom cover 20 is made of a steel plate formed such that the center portion is higher than the edge portion. Although the material which comprises the bottom cover 20 is not limited to a steel plate, it needs to have sufficient proof strength with respect to the pressure and frictional force which act at the time of drilling the natural ground G.

  After the bottom lid 20 is inclined so as to become higher from the periphery toward the center, the center portion 21 is formed so that the center protrudes downward, so that the cross section is formed in an M shape. . The central portion 21 does not necessarily have to protrude downward. Further, the bottom cover 20 may be recessed in an arc shape (a bowl shape).

  As shown in FIG. 4B, the bottom lid 20 is formed with two slits 22 that open along the radial direction. The number and shape of the slits 22 are not limited. The bottom lid 20 is formed with a locking hole 23 at a location corresponding to the locking member 16 of the bucket body 10. Further, a trillion number 15 is connected to a portion facing the locking hole 23 across the center portion of the bottom cover 20.

  A plurality of slit bits (cutter bits) 24, 24,... Are juxtaposed along the edge of the slit 22.

The bottom lid 20 is installed on the bucket body 10 via a trillion number 15 so as to be freely opened and closed. During excavation, the locking member 16 is locked in the locking hole 23 to shield the lower end portion of the bucket body 10, and when the earth and sand are discharged after excavation, the locking state of the locking member 16 is released to lower the lower end portion. Is released.
The method for connecting the bucket body 10 and the bottom lid 20 is not limited. For example, in the present embodiment, the bottom lid 20 is locked by one locking member 16, but a plurality of locking members 16 may be arranged.

  The auxiliary bucket 30 is connected to the upper end of the bucket body 10 as shown in FIG. Since the structure of the auxiliary bucket 30 is the same as that shown in the first embodiment, detailed description thereof is omitted.

  Moreover, since the method for forming the excavation hole H by the drilling bucket 2 according to the second embodiment is the same as the contents shown in the first embodiment, detailed description thereof is omitted.

  Since the effect by the drilling bucket 2 is the same as that of the drilling bucket 1 of 1st Embodiment, detailed description is abbreviate | omitted.

As mentioned above, although preferred embodiment was described about this invention, this invention is not limited to said each embodiment, A design change is possible suitably in the range which does not deviate from the meaning of this invention.
For example, in the above-described embodiment, the case where the auxiliary bucket is provided on the upper portion of the bucket body has been described. However, the auxiliary bucket may be disposed as necessary, and may be omitted.

  Moreover, in the said embodiment, although the stabilizer shall be arrange | positioned to an auxiliary bucket, you may arrange | position a stabilizer to a bucket main body. In addition, the stabilizer is not necessarily provided and can be omitted.

1, 2 Drilling bucket 10 Bucket body 13, 25 Cutter bit 20 Bottom cover 22 Slit 24 Slit bit (Cutter bit)
30 Auxiliary bucket 31 Opening 32 Stabilizer K Kelly bar

Claims (4)

A drilling bucket comprising a bucket body formed in a cylindrical shape, and a bottom lid disposed at the bottom of the bucket body,
The bottom cover includes a slit, a plurality of cutter bits juxtaposed along the slit, and a plurality of cutter bits juxtaposed so as to protrude downward along the edge portion, A drilling bucket, wherein a center portion of a bottom lid is formed to be higher than an edge portion. A drilling bucket comprising a bucket body formed in a cylindrical shape, and a bottom lid disposed at the bottom of the bucket body,
The bucket body has a plurality of cutter bits with a lower end protruding below the bottom lid and disposed at the lower end,
The bottom lid is formed with a slit and a plurality of cutter bits arranged in parallel along the slit, and the center portion is formed to be higher than the edge portion. . A cylindrical auxiliary bucket connected to the upper part of the bucket body,
The drilling bucket according to claim 1, wherein an opening is formed in the auxiliary bucket at a location corresponding to a joint portion between the bucket body and the kelly bar. The drilling bucket according to claim 3, further comprising a stabilizer at an upper end portion of the auxiliary bucket.

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