JP2002004326A - Excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excavator, in which an excavating section can be inserted and pulled out easily before and after excavating works and which enables excavation without leaving a range that the sectional area of a easing is covered in the case of excavation, in the excavator conducting pipe jacking prior to the press-in of the easing by a bit installed at the front end of the excavating section, pressing the easing into a ground under the state in which the excavating section is inserted into the easing. SOLUTION: The bit is composed of a minor-axis bit and a major-axis bit oppositely mounted to an axis, and constituted so that the radius of gyration of the minor-axis bit is made smaller than the inner circumference of the casing and the rotary range of the major-axis bit is made larger than an area surrounded by the outer circumference of the easing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a drilling rig having a bit.

[0002]

2. Description of the Related Art The present applicant has filed a Japanese Patent Application No. Hei 10-53648.
In No. 9, a method for constructing an underground building was disclosed. Since the present invention relates to an excavator for implementing the method for constructing an underground structure, the method for constructing the underground structure will be described very simply with reference to FIGS.

[0003] The basic idea of this construction method is that a plate body is laid in the ground in parallel to form a formwork and a soil, and a groove space is formed by removing earth and sand between the laid plate bodies. Reinforcing bars and steel cages in concrete, placing concrete, and pulling out and removing at least the plate on the inner wall side of the underground building before the concrete hardens, eliminating the need for formwork for building the underground building It was made possible.

Next, FIG. 3 shows a procedure of an excavation method using a casing 20 having a rectangular cross section as shown in FIG. 2 for removing soil and sand between the plate bodies more efficiently.
As shown in FIG. 3A, the plate 23 is temporarily fixed to the outer surface 21 of the casing 20 by some means, for example.
FIG. 3B shows a state in which the plate body 23 is arranged along the side surface of the casing 20.
, The casing 20 and the plate body 23 are simultaneously inserted into the ground G. At this time, since the bottom of the casing 20 is open, the earth and sand G1 enters the inside of the casing 20. When the casing 20 and the plate 23 have reached a predetermined depth, the upper end of the plate 23 is pressed by appropriate means, and FIG.
As shown in (c), only the casing 20 is pulled out of the ground G together with the soil G1 that has entered the inside. As a result, the earth and sand between the plate bodies 23 is removed, and the groove space S is formed.

Next, an excavator 30 for performing the excavation method using the above-described casing 20 will be described with reference to FIGS. Excavator 30 and casing 2
The plate 23 (see FIG. 3) driven into the ground G along the 0 and the casing 20 can be moved up and down, moved, and adjusted in position by a jack device, a crane device, and a leader (not shown). 4 and 5, illustration of the plate body 23 is omitted.

As shown in FIG. 4, the excavator 30 includes a hydraulic motor 35 for rotating a pair of auger screws 33 up and down, and a guide device 34 for supporting the casing 20. The excavation unit of the excavator 30
Auger screw 33 and bit 3 provided at its tip
2. As shown in FIG.
In order to perform excavation, first, the excavator 30 and the casing 21 are aligned using a jack device, a crane device, a leader, and the like (not shown), and the excavator of the excavator 30 is inserted into the casing 21 according to the arrow A. The upper end of the casing 20 is positioned by the guide device 34. Next, the auger screw 3 is driven by the hydraulic motor 35.
3 starts the excavation by rotating
0 press fit. The press-in resistance of the excavator 30 and the casing 20 is set such that the excavation position of the bit 32 always precedes the lower end of the casing 20 as shown in FIG. When the casing 20 is press-fitted to a predetermined position while the excavated earth and sand is discharged upward by the auger screw 33, the excavator 30 is raised by the hydraulic motor 35 and a leader (not shown), and the casing 20 is moved by a crane (not shown). Pull out from the ground G using.

[0007]

The drilling rig 3
5 is pulled out of the casing 20 as shown in FIG.
As shown in (2), the outer peripheral range α of the bit 32 indicated by oblique lines needs to be within the inner periphery of the casing 20. On the other hand, if the rotation range of the bit 32 is only α, the portion of the casing 20 that is not covered by the oblique lines in the drawing is excavated and left, and the bit 3 is pressed before the casing 20 is pressed.
This is inconvenient for the excavation method of excavating the ground in step 2 to smoothly press-fit the casing 20. That is, in order to carry out the above-described excavation method, the rotation range of the bit 32 needs to exceed the cross-sectional area surrounded by the outer periphery of the casing 20, as shown in FIG.

[0008]

In order to solve such a problem, in the excavator according to the present invention, when excavating, the turning diameter of the bit is larger than the outer circumference of the casing,
When the drilling device is pulled out of the casing after the excavation, the bit is composed of a short-diameter bit and a long-diameter bit mounted opposite to the shaft so that the bit can be accommodated in the inner periphery of the casing. It is characterized in that the rotation diameter of the bit is smaller than the inner circumference of the casing, and the rotation range of the long diameter bit is larger than the area surrounded by the outer circumference of the casing.

[0009] With this configuration, a drilling device that excavates prior to press-fitting the casing by a bit provided at the tip of the excavation portion while press-fitting the casing into the ground with the excavation portion inserted into the casing. In this case, the bit can be excavated while always covering the cross-sectional area of the casing before the casing.

[0010] The excavation part can be composed of a two-axis earth auger, and a short diameter bit and a long diameter bit provided at the tip of each shaft of the earth auger.

In another aspect of the excavator according to the present invention, the rotation axis of the bit is eccentrically mounted in the outer peripheral direction of the casing from the center of the bit, so that when the bit rotates, the short diameter of the bit is reduced. The same effect can be achieved by configuring the rotating shaft so as to be smaller than the inner periphery of the casing and the rotation range of the major axis of the bit to be larger than the area surrounded by the outer periphery of the casing.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a drilling rig according to the present invention will be described below with reference to the drawings. FIG. 1 is a view showing an embodiment of a drilling device 1 according to the present invention, in which FIG. 1 (a) is a schematic diagram of the entire drilling device 1, FIG. 1 (b) is an enlarged view of a bit 2, FIG. (C) is a plan view of the bit 2, FIG.
(D) is a diagram schematically showing the rotation diameter of the bit 2.

As shown in FIG. 1A, the basic configuration of an excavator 1 according to the present embodiment is the same as that of the excavator 30 described in the conventional example, and the same reference numerals denote the same components. This is indicated by using reference numerals. That is, the excavator 1
Is provided with a hydraulic motor 35 for rotating the pair of auger screws 33 up and down and a guide device 34 for supporting the casing 20. The excavating part of the excavating device 1 includes an auger screw 33 and a bit provided at the tip thereof. 2 excavates the ground while the bit 2 rotates prior to the press-fitting of the casing 20.

As shown in FIGS. 1 (b) and 1 (c), the bit 2 is composed of a short-diameter bit 2a and a long-diameter bit 2b which are respectively attached to a pair of bit shafts 2c so as to face each other. As shown in FIG. 1 (d), the rotation diameter α of the short diameter bit 2 a is set within the inner circumference of the casing 20. On the other hand, the rotation diameter β of the long diameter bit 2b is
And the rotation range of the pair of long-diameter bits is overlapped, so that excavation can be performed without leaving an area surrounded by the outer periphery of the casing 20.

When the excavated portion of the bit device 1 is inserted into the casing 20 before the excavation is started, as shown in FIG. By rotating the bit 2 so that it is located on the side, the entire bit 2 can be accommodated in the inner periphery of the casing 20. On the other hand, when excavation is started, the short diameter bit 2a and the long diameter bit 2b rotate, and FIG.
As shown in (d), since the rotation range β of the long diameter bit 2b exceeds the area of the range surrounded by the outer periphery of the casing 20, the ground covering the entire area in the casing 20 can be excavated. The press-in resistance of the digging device 30 and the casing 20 always indicates that the digging position of the bit 2 is
Set to precede the bottom of When the casing 20 is press-fitted to a predetermined position while the excavated earth and sand is discharged upward by the auger screw 33, the excavator 30 is raised by the hydraulic motor 35 and a leader (not shown), and the casing 20 is moved by a crane (not shown). Pull out from the ground G using. When the excavation is completed, the drill 2 is pulled out of the casing 20 by rotating the bit 2 so that the short-diameter bit 2a of the bit 2 is positioned on the outer peripheral side and storing the bit 2 in the casing 20.

The shapes of the short diameter bit 2a and the long diameter bit 2b are not limited to those shown in the figures, and various shapes can be considered. The bit 2 does not have to be formed integrally with the shaft of the auger screw 33, and the bit portion can be configured to be replaceable.

Further, in the above embodiment, each of the pair of bits 2 is composed of a short diameter bit and a long diameter bit. However, each of the pair of bits 2 is composed of a single bit, and the position of the mounting shaft 2c of each bit is set. Is eccentric to the outer peripheral side, a similar effect can be obtained. In this case, the mounting positions of the respective bits on the shaft 2c can be shifted up and down instead of in the same plane.

Further, in the above embodiment, a pair of bits each having a bit attached to two shafts is disclosed, so that a range exceeding the outer peripheral area of the casing 20 can be excavated by rotating both of the two long diameter bits 2b. But
The feature of the present invention is that when drilling, the rotating diameter of the bit is larger than the outer circumference of the casing, and when the drilling device is pulled out of the casing after the excavation, the bit can be stored in the inner circumference of the casing. And the bits need not necessarily be two axes.

For example, when the bit axis is composed of three or more axes,
Casing 20
May be excavated in a range exceeding the outer peripheral area, or conversely, it may be possible to excavate a range in which the excavation range of the long diameter bit exceeds the outer peripheral area even with one axis. Further, the short-diameter bit and the long-diameter bit may be formed integrally or may be formed separately.

In this embodiment, the casing 20 having a rectangular cross section is used. However, the excavator according to the present invention can be used with any casing having any cross section.

[0021]

According to the present invention, a drilling device for excavating prior to press-fitting of a casing by a bit provided at the tip of the excavating portion while press-fitting the casing into the ground with the excavated portion inserted into the casing. In, the digging part can be easily inserted into and pulled out of the casing before and after the digging work, and the digging can be done without leaving the area that covers the cross-sectional area of the casing with the bit at the time of digging. Digging method can be reliably implemented.

[Brief description of the drawings]

1A is a schematic overall view of an excavator according to an embodiment of the present invention, FIG. 1B is an enlarged view of a bit, FIG. 1C is a sectional view of the bit, and FIG. It is a figure which shows typically.

FIG. 2 is a perspective view showing an appearance of a casing.

FIGS. 3A, 3B, and 3C are cross-sectional views illustrating an excavation procedure using a casing.

FIGS. 4A and 4B are diagrams showing a conventional excavator.

FIGS. 5A and 5B are diagrams schematically showing the rotation diameter of a bit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Excavator 2 Bit 20 Casing 33 Auger screw 34 Guide device 35 Hydraulic motor

Claims (3)

[Claims] 1. An excavating device having an excavating portion that can be inserted through a casing, wherein the excavating portion is inserted into the casing and provided at a tip of the excavating portion while press-fitting the casing into the ground. In a drilling machine which excavates prior to press-fitting the casing by a bit, the bit comprises a short-diameter bit and a long-diameter bit which are attached to face the shaft, and the rotation diameter of the short-diameter bit is set in the casing. An excavator, wherein the excavator is smaller than a circumference and a rotation range of the long diameter bit is larger than an area surrounded by an outer periphery of the casing. 2. The excavator according to claim 1, wherein the excavating part comprises a two-axis earth auger, and a short bit and a long bit provided at the tip of each shaft of the earth auger. 3. A digging device having a digging portion that can be inserted through a casing, wherein the digging portion is inserted into the casing and provided at the tip of the digging portion while the casing is pressed into the ground. In a drilling machine which excavates prior to press-fitting of the casing by means of a bit, by mounting the rotating shaft of the bit eccentrically from the center of the bit toward the outer periphery of the casing, the bit is rotated when the bit rotates. An excavator, wherein the rotation diameter of the minor axis is smaller than the inner circumference of the casing, and the rotation range of the major axis of the bit is larger than the area surrounded by the outer circumference of the casing.