JP2023116136A - Enlarging excavator - Google Patents

Abstract

To provide an enlarging excavator having a simple structure composed only of mechanical elements, having high strength, and having a higher enlarging excavation rate than a conventional enlarging excavator.SOLUTION: An enlarging excavator 100 comprises a drilling shaft 10 that can be integrally connected to a tip of a drilling rod, a plurality of support shafts 13 that are arranged on an outer periphery of the drilling shaft 10, parallel to the axis 10c of the drilling shaft 10, and arranged at equal intervals along the circumferential direction of the drilling shaft 10, and enlarging blades 11 rotatably attached to each support shaft 13. During pile hole excavation work in which the drilling rod rotates forward in the direction of arrow R, the enlarging blade 11 that receives earth pressure maintains a reduced diameter state. During the enlarging excavation work in which the enlarging rod rotates in the direction of the arrow L in the opposite direction, the enlarging blade 11 receives earth pressure and rotates around the support shaft 13 to enlarge the diameter. In this state, the drilling shaft 10 and the plurality of enlarging blades 11 rotate in the direction of the arrow L to enlarge and drill the surrounding ground.SELECTED DRAWING: Figure 2

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an enlarging excavator used for construction work for enlarging and excavating a tip portion of a pile hole formed in the ground to form a hardening bulb portion.

Conventionally, various structures and functions have been proposed for enlarging excavation devices that form a foot protection bulb by enlarging the tip of a pile hole formed in the ground, but related to the present invention. For example, there is an "enlarged excavator" described in Patent Document 1, and the like.

The "enlarged drilling device" described in Patent Document 1 is used by being connected to the tip of the drilling rod so as to rotate integrally with the drilling rod. a drive shaft, two helical excavation blades provided on the outer periphery thereof, an excavation blade attached to the tip of each excavation wing, and a diameter-expanded state provided along the spiral of each excavation wing. It has two enlarging wings configured to be switchable to a diameter-reduced state.

The two expansion blades are swingably supported by a pin on a bracket connected to the excavation blade, and during pile hole excavation in which the excavation rod is rotated forward, the majority of the blades are accommodated within the rotation trajectory of the excavation blade due to soil pressure. By rotating the excavating rod in the opposite direction, the expanding wing receives soil pressure and swings around the pin. It is configured.

JP 2011-214366 A

The "enlarging excavator" described in Patent Document 1 is provided along the spiral of two excavating blades exhibiting a spiral shape, and is configured to be switchable between an enlarged diameter state and a reduced diameter state. However, since the size of the expansion wing (size in the radial direction of the rotating surface of the drilling rod) is smaller than that of the excavation wing, there is a problem that the expansion excavation rate is low.

In addition, in the above-mentioned "expansion excavation device", if the size of the expansion wing is increased in order to increase the expansion excavation rate, the load applied to the vicinity of the bracket due to the earth pressure during the expansion excavation work will be excessive, increasing the possibility of damage. In reality, it is difficult to increase the expansion excavation rate by increasing the size of the expansion wing.

Therefore, the problem to be solved by the present invention is to provide an enlarged excavator which has a simple structure composed only of mechanical elements, is high in strength, and has a higher enlargement excavation rate than conventional enlarged excavators. .

The enlarging excavator according to the present invention includes:
a drilling shaft connectable to the tip of the drilling rod so as to rotate integrally with the drilling rod;
a plurality of support shafts parallel to the axial center of the excavation shaft on the outer periphery of the excavation shaft and arranged at equal intervals along the circumferential direction of the excavation shaft;
and an enlarged wing rotatably attached to the support shaft,
During pile hole excavation work in which the excavation rod rotates forward, the enlarged wing that receives earth pressure maintains a reduced diameter state,
During the expansion excavation work in which the excavation rod rotates in the reverse direction, the expansion wing that receives the earth pressure rotates around the support shaft and expands until a part of the expansion wing abuts the outer circumference of the excavation shaft. It is characterized by retaining the diameter state.

In the enlarging excavator, a plurality of the enlarging wings can be arranged so as to overlap each other along the axial direction of the excavating shaft.

The enlarging excavator may be provided with a diameter expansion confirming member that is sheared by the rotation of the enlarging wings to the diameter expanding state.

At least one conical bit may be provided on at least one of the upper surface and the lower surface of the expanding wing in the expanding rig.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an enlarged excavating apparatus which has a simple structure composed only of mechanical elements, has high strength, and has a higher enlargement excavation rate than conventional enlarged excavating apparatuses.

BRIEF DESCRIPTION OF THE DRAWINGS It is a partially-omission front view which shows the expansion drilling apparatus which is embodiment of this invention. FIG. 2 is a partially omitted horizontal cross-sectional view taken along line AA in FIG. 1, showing a state in which the diameter of the expanding blade is reduced. FIG. 2 is a partially omitted horizontal cross-sectional view taken along the line AA in FIG. 1, showing a state in which the expanding wings are expanded in diameter; FIG. 2 is a partially omitted front view showing a state in which a drilling head is connected to the enlarged drilling device shown in FIG. 1; FIG. 2 is a partially omitted vertical cross-sectional view showing the state of use of the enlarging excavator shown in FIG. FIG. 11 is a partially omitted front view showing a state in which a drilling head is connected to an enlarged drilling device according to another embodiment; FIG. 7 is a partially omitted vertical cross-sectional view showing the state of use of the enlarging excavator shown in FIG. FIG. 7 is a partially omitted perspective view showing the vicinity of a diameter expansion confirming member of the expansion excavator shown in FIG. 6 ; FIG. 9 is a partially omitted perspective view showing the vicinity of a diameter expansion confirming member in FIG. 8; It is a partially-omission perspective view which shows the expansion excavation apparatus which is other embodiment.

An enlarged excavator 100, which is an embodiment of the present invention, will be described below with reference to FIGS. 1 to 5. FIG. The enlarged excavator 100 shown in FIGS. 1 to 3 includes, as shown in FIG. A drilling shaft 10 that can be connected to the tip of the driving shaft 2 of the drilling rod 1 provided with a spiral drilling blade 3 so as to rotate integrally with the drilling rod 1, and an axis of the drilling shaft 10 on the outer periphery of the drilling shaft 10. A plurality of supporting shafts 13 parallel to the center 10c and arranged at equal intervals along the circumferential direction of the excavation shaft 10, and an enlarging wing 11 rotatably attached to each supporting shaft 13. ing.

As shown in FIG. 1, each support shaft 13 is fixed at a position separated from the outer peripheral surface of the excavation shaft 10 via a pair of brackets 16, 16 separated in a direction parallel to the axis 10c. As shown in FIGS. 2 and 3, the expanding blade 11 has a tapered shape in which the width is continuously reduced as the distance from the support shaft 13 increases, and the tip portion 11d of the expansion blade 11 is parallel to the vertical direction (the direction of the axis 10c). A projection 11b projecting in a direction away from the distal end portion 11d and a recessed portion 11c adjacent to the projecting portion 11b and recessed in a direction toward the distal end portion 11d are provided on the base end side. . The expanding blades 11 are arranged at three locations on the outer circumference of the excavation shaft 10 at intervals of 120 degrees, but the shape, number and arrangement intervals of the expanding blades 11 are not limited to those shown in FIGS.

A diameter expansion confirming bolt 18 is arranged at a portion closer to the excavation shaft 10 than the support shaft 13 on the outer periphery of the plurality of brackets 16 . The structure and function of the vicinity of the diameter expansion confirmation bolt 18 will be described in detail in later paragraphs with reference to FIGS. 8 and 9. FIG.

As shown in FIG. 1, a hexagonal columnar connector 14a for connecting to the lower end portion of the driving shaft 2 of the drilling rod 1 is protruded from the upper end side of the drilling shaft 10, and the lower end side of the drilling shaft 10 has a A connector hole 14b into which a connector 22 projecting from the upper end side of the driving shaft 21 of the drilling head 20 shown in FIG. 4 can be inserted is bored in the direction of the axis 10c.

When using the enlarged excavating apparatus 100 shown in FIG. 1, the excavating head 20 is connected to the lower end side of the enlarged excavating apparatus 100 as shown in FIG. The excavation head 20 includes a cylindrical drive shaft 21 , a hexagonal columnar connector 22 projecting from the upper end side of the drive shaft 21 , and a spiral excavation blade 23 provided on the outer periphery of the drive shaft 21 . ing. The connector 22 on the upper end side of the excavating head 20 is inserted into the connector hole 14b on the lower end side of the excavating shaft 10 of the enlarged excavating device 100, and the enlarged excavating device 100 and the excavating head 20 are fixed by a predetermined fixing means. integrally connected.

Next, as shown in FIG. 4 , the enlarged drilling device 100 integrated with the drilling head 20 is connected to the tip of the drive shaft 2 of the drilling rod 1 so as to rotate integrally with the drilling rod 1 . Specifically, the connector 14a on the upper end side of the excavating shaft 10 of the enlarging excavating device 100 is fitted into the connector hole 4 (see FIG. 5) drilled at the tip of the drive shaft 2, and fixed by a predetermined fixing means. Thus, the drilling rod 1, the enlarged drilling device 100 and the drilling head 20 are integrally connected. Thereby, the enlarged drilling device 100 and the drilling head 20 are connected to rotate integrally with the drilling rod 1 .

Here, based on FIGS. 2 to 5, the functions, effects, etc. of the enlarging wing 11 constituting the enlarging excavator 100 will be described.

As shown in FIG. 5, during pile hole excavation work, the excavation rod 1 is rotated forward in the direction of the arrow R. At this time, as shown in FIG. Since it is kept close to the excavation shaft 10, the enlarged wing 11 is kept in a contracted state. Therefore, by rotating the excavation rod 1 forward in the direction of the arrow R, the pile hole excavation work can be performed smoothly.

On the other hand, during the expansion excavation work, the excavation rod 1 is reversely rotated in the direction of the arrow L. At this time, as shown in FIG. Then, the projection 11b of the expansion wing 11 expands until it comes into contact with the outer circumference of the excavation shaft 10, and as shown in FIG. Therefore, the circumference of the expansion blade 11 of the pile hole H formed in the ground shown in FIG. The ground is excavated in an enlarged manner, and a hardening bulb portion (not shown) having an inner diameter larger than that of the pile hole H is formed.

As described above, the expansion wing 11 of the expansion excavation device 100 shown in FIG. 3 draws a large radius of rotation and rotates in the direction of the arrow L to expand and excavate the ground around the pile hole H (see FIG. 5). The enlargement excavation rate can be increased compared with the conventional enlargement excavation apparatus. Further, when the expansion wing 11 rotates in the direction of the arrow L to excavate the ground, the reaction force of the earth pressure generated in the projection 11b is supported by the outer circumference of the excavation shaft 10 (the portion in contact with the projection 11b). , which is hard to damage and exhibits high strength while having a simple structure.

Further, as shown in FIG. 3, since the support shaft 13 is arranged at a position away from the outer periphery of the excavation shaft 10, the earth and sand accumulated between the support shaft 13 and the reaction force point (projection 11b) spreads. A smooth diameter expansion operation can be ensured without biting when the blade 11 expands in diameter.

After the expansion excavation work is completed, when the excavation rod 1 (see FIG. 5) is rotated forward in the direction of the arrow R, the plurality of expansion wings 11 subjected to the earth pressure return to the contracted state shown in FIGS. 1 and 2, respectively. Therefore, the enlarged drilling device 100 and the drilling head 20 can be easily pulled up on the ground together with the drilling rod 1 .

The enlarging wing 11 constituting the enlarging excavating apparatus 100 expands or contracts the diameter only by rotating the excavating shaft 10 in the reverse direction or the forward direction through the excavating rod 1, so that the hydraulic system, No electrical operating system is required. Therefore, the enlarging excavator 100 can be composed only of mechanical elements and has a simple structure.

Next, an enlarged excavator 200 of another embodiment will be described with reference to FIGS. 6 to 9. FIG. In the enlarged excavating apparatus 200, the same reference numerals as those shown in FIGS. 1 to 5 are attached to the portions common to the enlarged excavating apparatus 100 described above, and the description thereof is omitted.

FIG. 6 shows a state in which the drilling head 20 is integrally connected to the enlarged drilling device 200 . As shown in FIG. 6, in the enlarging excavating device 200, an upper enlarging wing 11 and a lower enlarging wing 12 are arranged at the position of the enlarging wing 11 of the enlarging excavating device 100 shown in FIG. The upper enlarging wing 11 and the lower enlarging wing 12 are stacked along the axial center 10c direction of the excavating shaft 10 and attached to the outer circumference of the excavating shaft 10 via the support shaft 13 and the bracket 16 .

The upper enlarging wing 11 and the lower enlarging wing 12 are rotatable around the support shaft 13 without interfering with each other. The shape and function of the upper expanding wing 11 and the lower expanding wing 12 are the same as those of the expanding wing 11 shown in FIGS. are doing.

The usage of the enlarged excavator 200 is the same as that of the enlarged excavator 100 shown in FIG. As shown in FIG. 7 , the enlarged drilling device 200 is used together with the drilling head 20 by being connected to the tip portion of the drilling rod 1 so as to rotate together with the drilling rod 1 .

The upper enlarging wing 11 and the lower enlarging wing 12 constituting the enlarging excavating apparatus 200 can be expanded as shown in FIGS. Since it expands and contracts in the same way as 11, it does not require a hydraulic or electrical operating system. Therefore, the enlarging excavator 200 can be composed only of mechanical elements and has a simple structure.

The upper enlarging wing 11 and the lower enlarging wing 12 share the support shaft 13 and are arranged so as to overlap along the axial center 10c direction of the excavation shaft 10, and the upper enlarging wing 11 and the lower enlarging wing 12 have the same structure, function, etc. Since it has, it is effective in improving the efficiency of the enlarged excavation work.

As shown in FIGS. 8 and 9, in the enlarged excavator 200, a nut 17 is fixed to a portion of the outer periphery of the bracket 16 closer to the excavation shaft 10 than the support shaft 13. As shown in FIGS. The nut 17 is fixed so that its axial direction is parallel to the support shaft 13 , and a diameter expansion confirming bolt 18 made of synthetic resin is screwed to the nut 17 .

When the upper enlarging wing 11 and the lower enlarging wing 12 are in the contracted state, the tip portion 18a of the diametrical expansion confirming bolt 18 is separated from the upper enlarging wing 11 and the lower enlarging wing 12. The leading end portion 18a of is positioned within the operating range when the upper enlarging wing 11 and the lower enlarging wing 12 are rotated to the enlarged diameter state. Therefore, when the upper enlarging wing 11 and the lower enlarging wing 12 are rotated to the expanded state, the tip portion 18a side of the diameter expansion confirming bolt 18 is sheared.

That is, as shown in FIG. 9, when the recessed portion 11c of the upper enlarging wing 11 passes below the nut 17 in the process of rotating the upper enlarging wing 11 to the expanded diameter state, the recessed portion 11c and the nut 17 are brought into contact with each other. The tip portion 18a side of the diameter expansion confirming bolt 18 is sheared by the shearing action generated during the above. This shearing action occurs in the lower spreader 12 as well.

Therefore, by visually confirming whether or not the diameter expansion confirmation bolt 18 of the enlarged excavation device 200 has been sheared after the enlarged excavation work is completed, the upper enlarging wing 11 and the lower enlarging wing 12 can be confirmed during the enlarging excavation work. It is possible to confirm whether or not the diameter has been expanded. Thereby, it can be confirmed whether or not a hardening bulb portion of a predetermined size has been formed at the tip portion of the pile hole H. If the diameter expansion confirmation bolt 18 with the tip portion 18a side sheared off is removed from the nut 17 and a new diameter expansion confirmation bolt 18 is screwed onto the nut 17, the function as the diameter expansion confirmation means is reproduced.

2 and 3 are provided in the same manner as the nut 17 and diameter expansion confirmation bolt 18 shown in FIGS. The same effect as the diameter expansion confirming bolt 18 is exhibited.

When the excavating rod 1 (see FIG. 7) is rotated forward in the direction of the arrow R after the expansion excavation work is completed, the upper enlarging wings 11 and the lower enlarging wings 12 return to the contracted state shown in FIGS. , the operation of pulling up the enlarged excavator 200 is easy.

Next, an enlarged excavator 300, which is another embodiment, will be described with reference to FIG. are assigned the same reference numerals and the description thereof is omitted.

As shown in FIG. 10, in the enlarging excavator 300, a plurality of conical bits 19 are provided on the upper surface 11a of the upper enlarging wing 11 and the lower surface 12b of the lower enlarging wing 12, respectively. The conical bits 19 are welded via bases 19a.

Pointed ends 19b of the plurality of conical bits 19 on the upper surface 11a of the upper enlarging wing 11 move upward in the direction of the arrow L and away from the excavating shaft 10 when the excavating shaft 10 rotates in the direction of the arrow L. It is arranged at an angle so that

The sharp ends 19b of the plurality of conical bits 19 on the lower surface 12b of the lower enlarging wing 12 are directed downward in the direction of the arrow L and away from the excavation shaft 10 when the excavation shaft 10 rotates in the direction of the arrow L. It is arranged at an angle so that

As shown in FIG. 10, by providing a plurality of conical bits 19 on the upper surface 11a of the upper expanding wing 11 and the lower surface 12b of the lower expanding wing 12, respectively, the upper expanding wing 11 and the lower expanding wing 12 can be expanded and contracted. Radial movement can be speeded up and ensured, and it is also effective in improving the efficiency of enlarged excavation work.

The enlarged excavating apparatus 100, 200, and 300 described with reference to FIGS. 1 to 10 are examples of the enlarged excavating apparatus according to the present invention. , 200, 300.

INDUSTRIAL APPLICABILITY The enlarging excavator according to the present invention can be widely used in fields such as the civil engineering and construction industry as a device for enlarging and excavating the tip of a pile hole formed in the ground to form a hardening bulb. can.

Reference Signs List 1 drilling rod 2, 21 drive shaft 3, 23 drilling blade 4, 14b connector hole 10 drilling shaft 10c axial center 11 expanding wing (upper expanding wing)
11a upper surface 11b projection 11c recess 11d tip 12 lower enlarging wing 12b lower surface 13 spindle 14a, 22 connector 16 bracket 17 nut 18 diameter expansion confirmation bolt 18a tip 19 conical bit 19a base 19b tip 20 excavation head 100, 200, 300 expansion drilling equipment

Claims (4)

a drilling shaft connectable to the tip of the drilling rod so as to rotate integrally with the drilling rod;
a plurality of support shafts parallel to the axial center of the excavation shaft on the outer periphery of the excavation shaft and arranged at equal intervals along the circumferential direction of the excavation shaft;
and an enlarged wing rotatably attached to the support shaft,
During pile hole excavation work in which the excavation rod rotates forward, the enlarged wing that receives earth pressure maintains a reduced diameter state,
During the expansion excavation work in which the excavation rod rotates in the reverse direction, the expansion wing that receives the earth pressure rotates around the support shaft and expands until a part of the expansion wing abuts the outer circumference of the excavation shaft. An enlarging excavator characterized by retaining a diameter state. 2. The enlarging excavating apparatus according to claim 1, wherein a plurality of said enlarging wings are arranged so as to overlap along the axial direction of said excavating shaft. 3. The enlarging excavator according to claim 1, further comprising a diameter expansion confirming member that is sheared by rotating said enlarging wings to said diameter expanding state. The enlarging excavating apparatus according to any one of claims 1 to 3, wherein at least one conical bit is provided on at least one of the upper surface and the lower surface of the enlarging wing during enlarging excavation work.

Images