JPH0953381A - Method of drilling ground and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower the center of gravity of the whole device and make a rotat ing shaft having a circular section usable. SOLUTION: A chuck of a lower driving device 5 is released, a rotating shaft 6 is chucked by an upper driving device 4 to rotate the rotating shaft 6 by the upper driving device 4, and the rotating shaft 6 is lowered together with the upper driving device 4 to drill the ground 7. After the upper driving device 4 is lowered, the rotating shaft 6 is chucked by the lower driving device 5 to rotate the rotating shaft 6 by the lower driving device 5, the chuck of the rotating shaft 6 by the upper driving device 4 is released, and the rotating shaft 6 is lowered together with the lower driving device 5 in this state to drill the ground 6. The upper driving device 4 is raised simultaneously with the lowering of the lower driving device 5. At a point of time when the lower driving device 5 is lowered, and the upper driving device 4 is also raised, the rotating shaft 6 is chucked by the upper driving device 4 to rotate the rotating shaft 6 by the upper driving device 4, and the chuck of the rotating shaft 6 by the lower driving device 5 is released. The rotating shaft 6 is lowered together with the upper driving device 4 in this state to drill the ground 7. These processes are repeated, whereby the ground 7 is drilled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground excavation method and apparatus.

[0002]

2. Description of the Related Art In a conventional ground excavating device, a driving device is attached to a reader provided upright on the device body so as to be vertically movable, an upper end of a rotary shaft is attached to the driving device, and the rotary shaft is rotated by the driving device. The weight of the drive unit is added to the rotary shaft, and the rotary shaft is inserted into the ground for excavation. However, with this, when the rotary shaft is completely pulled up to the ground, the heavy drive device with the upper end of the rotary shaft attached is located at the upper end of the reader, that is, at a position considerably higher than the ground, As a result, the center of gravity of the entire device increases,
It was dangerous because it could cause the device to fall over.

Therefore, Japanese Examined Patent Publication No. 4-68406 has been proposed as a means for lowering the center of gravity of the entire apparatus. In this conventional example, the driving device is provided in the lower portion of the reader to lower the center of gravity of the entire device and stabilize the device. That is, in the above-mentioned conventional example, the drive device for transmitting the rotational torque while allowing the axial movement with respect to the rotary shaft is provided in the lower portion of the reader.
In addition, the reader is provided with an upper elevating frame and a lower elevating frame separately from the driving device, and an upper chuck and a lower chuck are respectively provided on the upper and lower elevating frames, and a distance between the upper and lower elevating frames is reduced. Then, with the lower chuck of the lower lifting frame holding the rotary shaft, open the upper chuck of the upper lifter, and while lowering the lower lifter, rotate the rotary shaft with the drive device, and at the same time move the upper chuck. The upper lifting body is raised in the open state. At this time, the rotating shaft is rotated by receiving the rotating torque from the driving device, but since the rotating shaft is slidable in the axial direction, the driving device does not obstruct the lowering of the rotating shaft. After lowering the lower elevating frame by a predetermined stroke and raising the upper elevating frame by a predetermined stroke, contrary to the above, the rotating shaft is chucked by the upper chuck of the upper elevating frame and the lower chuck is released. At this time, the rotary shaft is continuously rotated by the drive device. Next, while the rotation shaft is being chucked by the upper chuck, the upper lifting frame is lowered to rotate and rotate the rotating shaft to lower the lifting frame integrally with the upper lifting frame. At the same time, the lower chuck is opened and lowered. Raise the frame. Next, after lowering the upper elevating frame by a predetermined stroke and raising the lower elevating frame by a predetermined stroke, the lower chuck chucks the rotary shaft,
Open the upper chuck. The same steps are repeated thereafter.

[0004]

[Problems to be Solved by the Invention]
In the conventional example disclosed in Japanese Patent Laid-Open No. 68406, the drive device must transmit rotational torque while allowing axial movement with respect to the rotating shaft. If so, the rotary shaft must have a square horizontal cross section (that is, in order to transmit rotational torque while allowing axial movement with respect to the rotary shaft, the rotary shaft must have a rectangular horizontal cross section, By inserting the rotary shaft into the square hole of the rotating frame by means of, the rotary torque can be transmitted while allowing the axial movement with respect to the rotary shaft. In that case, the rotating shaft can move not only in the vertical direction within the hole of the rotating frame but also in the rotating direction, and therefore the rotating torque cannot be transmitted to the rotating shaft). Therefore, conventionally, there is a problem that a normal rotary shaft having a horizontal horizontal section cannot be used.

Further, in the above-mentioned conventional example, when the rotary shaft is pushed down, the heavy load of the drive device is not applied to the rotary shaft. Therefore, it is necessary to push the rotary shaft into the ground for insertion. Needs to be pushed by a separate hydraulic jack for moving the upper and lower elevating frames or the lower elevating frame up and down. Therefore, it is necessary to use a large hydraulic jack.

An object of the present invention is to make it possible to continuously move the rotary shaft up and down while keeping the center of gravity of the entire apparatus as low as possible, and to use a rotary shaft having a circular cross section as the rotary shaft.
When pushing the rotary shaft into the ground, the load of the driving device can be applied to the rotary shaft and pushed in, and it is not necessary to provide a separate hydraulic jack for pushing the rotary shaft into the ground as in the conventional method and its method. To provide the equipment.

[0007]

According to the ground excavation method of the present invention, an upper drive unit 4 provided with a chuck unit 3 and a lower drive unit 5 provided with a chuck unit 3 are mounted on a reader 2 provided upright on an apparatus main body 1. And rotatably attached to the lower drive unit 5 and the rotary shaft 6 provided with excavating means at the lower end of the rotary shaft 6 released by the chuck unit 3 provided in the lower drive unit 5 by the chuck unit 3 of the upper drive unit 4. 6 is chucked to prevent the rotary shaft 6 from moving in the vertical direction with respect to the upper drive device 4, and the rotational drive force of the upper drive device 4 is transmitted to the rotary shaft 6, and in this state, together with the upper drive device 4, After lowering the rotary shaft 6 along the leader 2 to drill the ground 7 with the rotary shaft 6 and lower the upper drive device 4 by an arbitrary length, the rotary drive 6 is chucked by the chuck means 3 of the lower drive device 5. And the lower drive unit 5 The rotary drive force of the lower drive device 5 is transmitted to the rotary shaft 6 so that the rotary shaft 6 does not move in the vertical direction, and the chuck of the rotary shaft 6 by the chuck means 3 of the upper drive device 4 is released. The rotary shaft 6 is lowered along with the lower drive device 5 along the reader 2 to drill the ground 7 by the rotary shaft 6, and when the lower drive device 5 is lowered, the upper drive device 4 is moved along the leader 2 at the same time. Then, when the lower drive device 5 is lowered by an arbitrary length and the upper drive device 4 is raised by an arbitrary length, the chucking means 3 of the upper drive device 4 chucks the rotary shaft 6 to raise the upper drive device. 4, the rotary drive force of the upper drive device 4 is transmitted to the rotary shaft 6 so that the rotary shaft 6 does not move in the vertical direction, and the chucking of the rotary shaft 6 by the chuck means 3 of the lower drive device 5 is released. , In this state the top The rotary shaft 6 is lowered along with the moving device 4 along the leader 2 to drill the ground 7 with the rotary shaft 6, and at the same time when the upper driving device 4 is descending, the lower driving device 5 is moved along the leader 2. It is characterized by excavating the ground 7 by repeating the above steps.

Further, the ground improvement device of the present invention comprises a reader 2 provided in the device main body 1, an upper drive device 4 provided movably up and down on the reader 2 and repeatedly moved in a direction approaching each other and a direction separating from each other. Drive unit 5 and upper drive unit 4
And a lower drive unit 5 and a rotary shaft 6 provided with excavating means at the lower end thereof which are alternately rotated, and a chuck unit 3 capable of transmitting a rotary drive force to the upper drive unit 4 only in a chucked state. And a chuck means 3 capable of transmitting the rotational driving force to the rotary shaft 6 only in the chuck state in the lower drive device 5.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail with reference to the following embodiments. In the figure, reference numeral 1 denotes an apparatus main body, which is provided with a moving device such as a caterpillar, and a reader 2 is erected on the apparatus main body 1. An upper drive device 4 and a lower drive device 5 are attached to the reader 2 at positions below and approximately below the middle of the vertical direction so as to be vertically movable along the reader 2.
Although not shown in the drawings, the upper drive unit 4 and the lower drive unit 5 are hung from each other and can be moved up and down along the reader 2 by winding or rewinding the wire. ing.

The upper drive unit 4 and the lower drive unit 5 have the same structure. That is, the upper drive unit 4 and the lower drive unit 5 each include a rotating device 10 and a chuck means 3. The chuck means 3 has a structure as shown in FIGS. The drive device main body 9 which constitutes the main body of the upper drive device 4 and the lower drive device 5 is provided with a rotary cylinder 11 which is rotated by a rotary device 10. The rotary cylinder 11 is provided with a rotary shaft 6 having an excavating means 26 at its tip. It is inserted vertically. A disk-shaped support body 14 movable by a cylinder device 13 such as a hydraulic cylinder provided on a support frame 12 provided on the drive device main body 9 is provided, and a disk-shaped rotating body 15 is mounted on the support body 14 via a bearing. An arm 17 having an inclined surface 16 is rotatably attached, and an arm portion 17 having an inclined surface 16 is projected. The chuck body 18 is movably inserted into a window 19 provided in the rotary cylinder 11. When the inclined surface 16 of the arm portion 17 is opposed and the arm portion 17 is raised by driving the cylinder device 13, the chuck body 18 is pushed in and the rotary shaft 6 is chucked, and the rotary cylinder 11 of the rotary cylinder 11 is inserted through the chuck body 18. The rotation is transmitted to the rotary shaft 6 and the rotary shaft 6 is prevented from moving up and down with respect to the drive device body 9.

When the arm portion 17 is retracted, the pushing of the chuck body 18 is released, and the chuck of the rotary shaft 6 by the chuck body 18 is released. As described above, the cylinder device 13, the support 14, the rotating body 1
5, the arm portion 17, the chuck body 18, etc.
Is configured. Here, the rotary shaft 6 is attached to the chuck body 18.
The spring force in the direction away from may be biased.

As described above, the chuck means 3 is provided in each of the upper drive unit 4 and the lower drive unit 5. For example, in a state where the chuck means 3 of the lower drive device 5 releases the chuck of the rotary shaft 6 and the chuck means 3 of the upper drive device 4 chucks the rotary shaft 6, the rotary shaft 6 moves relative to the lower drive device 5. It is movable in the vertical direction, and the rotational driving force of the rotary device 10 of the lower drive device 5 is not transmitted to the rotary shaft 6, but the chuck means 3 of the upper drive device 4 chucks the rotary shaft 6 to rotate it. Axis 6 is upper drive unit 4
On the other hand, the rotational driving force of the rotating device 10 is transmitted to the rotating shaft 6 without moving up and down. Therefore,
In this state, by rotating the upper drive unit 4 up and down along the reader 2, the rotary shaft 6 moves in the vertical direction together with the upper drive unit 4, and at the same time, the rotary unit 6 provided in the upper drive unit 4 rotates the rotary shaft 6. It is a thing. On the other hand, the chuck means 3 of the upper drive device 4 releases the chuck of the rotary shaft 6,
In the state where the rotating shaft 6 is chucked by the chuck means 3 of the lower drive device 5, the rotating shaft 6 is vertically movable with respect to the upper drive device 4, and the rotation device 10 of the upper drive device 4 rotates. Although the driving force is not transmitted to the rotary shaft 6,
The chuck means 3 of the lower drive device 5 chucks the rotary shaft 6 so that the rotary drive force of the rotary device 10 is transmitted to the rotary shaft 6 without the rotary shaft 6 moving up and down with respect to the lower drive device 5. become. Therefore, in this state, when the lower drive device 5 is moved up and down along the reader 2, the rotary shaft 6 moves vertically with the lower drive device 5 and at the same time the rotary device 10 provided in the lower drive device 5 causes the rotary shaft 6 to move. It rotates.

Here, the rotary shaft 6 may have a non-circular shape having a square horizontal cross-section, but the horizontal cross-section may have a circular cross-section without any problem. That is, in the present invention, two drive devices, that is, the upper drive device 4 and the lower drive device 5, are provided.
The chucking means 3 provided in the upper drive unit 4 and the lower drive unit 5 alternately chuck the rotary shaft 6 to one of the drive units and drive the drive unit in a state in which the rotary shaft 6 does not move vertically with respect to the drive unit. Rotating device 10 provided in the device
Since the rotational driving force of the rotating shaft 6 is transmitted to the rotating shaft 6, the rotating shaft 6 can be horizontally moved as in the case of transmitting rotating torque while permitting axial movement with respect to the rotating shaft 6 of a conventional drive device. It is not necessary to have a non-circular cross section,
The rotary shaft 6 having a circular horizontal section can be used without any trouble. Therefore, in the present embodiment, a rotary shaft 6 having a circular horizontal cross section which has been commonly used in the past and is inexpensive is used.

In the embodiment shown in the drawings, a movable support 30 rotatably supporting the upper end of the rotary shaft 6 is provided above the upper drive unit 4 of the reader 2 so as to be vertically movable. However, since this moving support 30 is not provided with a drive unit, the weight of this portion is light, and the upper drive unit 4 and the lower drive unit 5 are located below the substantially intermediate position of the reader 2 and below the reader 2. Therefore, the center of gravity of the device as a whole is lowered, and the center of gravity can be lowered.

The excavation of the ground 7 using the excavation device having the above-described structure is performed as follows. That is, as shown in FIG. 1, the upper drive unit 4 is positioned at the upper limit position of its vertical movement range, and the rotary shaft 6 is chucked by the chuck means 3 of the upper drive unit 4 (in this case, the lower drive unit). The chuck means 3 of No. 5 does not chuck the rotary shaft 6 and leaves it free.) Then, by rotating the rotary device 10 of the upper drive device 4, the rotary drive force is applied to the rotary shaft 6 via the chuck means 3. Transmitted and rotating shaft 6
Rotates, and lowers the upper drive device 4 along the reader 2 while rotating the rotary shaft 6 in this manner. In this way, the rotary shaft 6 is rotated and inserted into the ground 7 for excavation.

When the upper drive unit 4 is lowered to an arbitrary position as shown in FIG. 2 as described above, the chuck shaft 3 is chucked by the chuck means 3 of the lower drive unit 5 and at the same time the upper drive unit 4 is moved. The chuck by the chuck means 3 is released to make the upper drive device 4 and the rotary shaft 6 free. In this state, the rotary driving force of the rotary device 10 of the lower drive device 5 is transmitted to the rotary shaft 6 via the chuck means 3 to lower the lower drive device 5 while rotating the rotary shaft 6, thereby lowering the rotary shaft 6 The rotating shaft 6 descends together with the lower drive device 5 while rotating, and the rotary shaft 6 is further inserted into the ground 7 for excavation. At the same time when the lower drive device 5 descends, the upper drive device 4, which is free from the rotary shaft 6, is moved to the upper limit position of its vertical movement range, and the state shown in FIG. 3 is obtained.

Next, in the state shown in FIG. 3, the chuck means 3 of the upper drive device 4 chucks the rotary shaft 6 and at the same time the chuck means 3 of the lower drive device 5 releases the chuck to release the lower drive device 5 and the rotary shaft. Free 6 and.
In this state, the rotational driving force of the rotating device 10 of the upper driving device 4 is transmitted to the rotating shaft 6 via the chuck means 3 to lower the upper driving device 4 while rotating the rotating shaft 6,
The rotating shaft 6 rotates and descends together with the upper drive device 4,
The rotary shaft 6 is further inserted into the ground 7 for excavation. When the upper drive device 4 descends, the rotary shaft 6
On the other hand, the lower drive device 5, which is free, is moved to the upper limit position of its vertical movement range, and the state shown in FIG. 4 is obtained.

Next, in the state of FIG. 4, the chuck shaft 3 is chucked by the chuck means 3 of the lower drive device 5, and at the same time, the chuck shaft 3 is released by the chuck means 3 of the upper drive device 4 to release the chuck. Free 6 and.
In this state, the rotational driving force of the rotating device 10 of the lower drive device 5 is transmitted to the rotary shaft 6 via the chuck means 3 to lower the lower drive device 5 while rotating the rotary shaft 6,
The rotating shaft 6 rotates and descends together with the lower drive device 5,
The rotary shaft 6 is further inserted into the ground 7 for excavation. When the lower drive unit 5 descends, the rotary shaft 6
On the other hand, the upper drive device 4, which is free, is moved to the upper limit position of the vertical movement range, and the state shown in FIG. 5 is obtained.

Next, in the state of FIG. 5, the chuck shaft 3 is chucked by the chuck means 3 of the upper drive device 4 and, at the same time, the chuck shaft 3 is released by the chuck means 3 of the lower drive device 5 and the lower drive device 5 and the rotary shaft. Free 6 and.
In this state, the rotational driving force of the rotating device 10 of the upper driving device 4 is transmitted to the rotating shaft 6 via the chuck means 3 to lower the upper driving device 4 while rotating the rotating shaft 6,
The rotating shaft 6 rotates and descends together with the upper drive device 4,
The rotary shaft 6 is further inserted into the ground 7 for excavation. When the upper drive device 4 descends, the rotary shaft 6
On the other hand, the lower drive device 6, which is free, is moved to the upper limit position of its vertical movement range.

By repeating the above steps, the rotary shaft 6 is inserted and excavated to a desired depth. On the other hand, when the rotary shaft 6 is inserted and excavated to a predetermined depth of the ground 7,
This time, the rotary shaft 6 is pulled up, but in this case, it is pulled up by the operation reverse to the above. 6 to 10 show the order of pulling up the rotary shaft 6. FIG. 6 shows a stage in the middle of pulling up. In the pulling up process in the previous stage of the state of FIG. 6, the chuck shaft 3 is chucked by the chuck means 3 of the upper drive unit 4 and at the same time the chuck unit 3 of the lower drive unit 5 is held. And the lower drive unit 5 and the rotary shaft 6 are made free. In this state, by moving the upper drive device 4 upward, the rotary shaft 6 is pulled up together with the upper drive device 4 by a certain length. At this time, the lower drive device 5, which is free with respect to the rotary shaft 6, moves to the lower limit position of the vertical movement range. As described above, the upper drive unit 4 moves to the upper limit position and the lower drive unit 5 moves to the lower limit position, and the state shown in FIG. 6 is obtained.

Next, when the state shown in FIG. 6 is reached, the chuck means 3 of the lower drive unit 5 chucks the rotary shaft 6 and at the same time the chuck means 3 of the upper drive unit 4 releases the chuck to release the upper drive unit 4 and the rotary shaft. Free 6 and.
In this state, by moving the lower drive unit 5 upward, the rotary shaft 6 is pulled up together with the lower drive unit 5 by a certain length. At this time, the upper drive device 4, which is free with respect to the rotary shaft 6, moves to the lower limit position of the vertical movement range. As described above, the lower drive device 5 moves to the upper limit position and the upper drive device 4 moves to the lower limit position, and the state shown in FIG. 7 is obtained.

Next, in the state shown in FIG. 7, the rotating shaft 6 is chucked by the chuck means 3 of the upper drive device 4, and at the same time, the chuck by the chuck means 3 of the lower drive device 5 is released to release the lower drive device 5 and the rotary shaft. Free 6 and.
In this state, by moving the upper drive device 4 upward, the rotary shaft 6 is pulled up together with the upper drive device 4 by a certain length. At this time, the lower drive device 5, which is free with respect to the rotary shaft 6, moves to the lower limit position of the vertical movement range. As described above, the upper drive unit 4 moves to the upper limit position and the lower drive unit 5 moves to the lower limit position, resulting in the state of FIG.

Next, in the state shown in FIG. 8, the chuck shaft 3 is chucked by the chuck means 3 of the lower drive unit 5, and at the same time, the chuck unit 3 of the upper drive unit 4 releases the chuck so that the upper drive unit 4 and the rotary shaft are rotated. Free 6 and.
In this state, by moving the lower drive unit 5 upward, the rotary shaft 6 is pulled up together with the lower drive unit 5 by a certain length. At this time, the upper drive device 4, which is free with respect to the rotary shaft 6, moves to the lower limit position of the vertical movement range. As described above, the lower drive unit 5 moves to the upper limit position and the upper drive unit 4 moves to the lower limit position, and the state shown in FIG. 9 is obtained.

Next, in the state shown in FIG. 9, the chuck shaft 3 is chucked by the chuck means 3 of the upper drive device 4, and at the same time, the chuck shaft 3 is released by the chuck means 3 of the lower drive device 5 and the lower drive device 5 and the rotary shaft. Free 6 and.
In this state, by moving the upper drive unit 4 upward, the rotary shaft 6 is pulled up together with the upper drive unit 4 for a certain length, and is completely pulled up to the ground as shown in FIG. At this time, as shown in FIG. 10, the upper drive device 4, which is free with respect to the rotary shaft 6, does not move in the vertical direction but is positioned at the upper limit position of the vertical movement range. By doing so, the initial state of FIG. 1 can be obtained. In this state, the device body 1 is moved to perform the next excavation.

In the step of pulling up the rotary shaft 6,
Rotating device 10 provided in the upper drive unit 4 and the lower drive unit 5
The rotation may be transmitted to the rotating shaft 6 and pulled up while rotating the rotating shaft 6, or the rotating device 10 may be pulled up without rotating (that is, the rotating shaft 6 does not rotate). By the way, in the above-described embodiment, when the upper drive device 4 is positioned at the upper limit position of the vertical movement range in the first stage shown in FIG. 1, the lower drive device 5 is set at the upper limit position of the vertical movement range. 1 to 2 so as not to move the lower drive device 5 in the vertical direction, and in the process from FIG. 9 to FIG. 10, the lower drive device 5 located at the upper limit position of the vertical movement range. In the first stage, as shown in FIG. 11 instead of FIG. 1, the upper drive device 4 is positioned at the upper limit position of its vertical movement range and The driving device 5 is positioned at the lower limit position of its vertical movement range, and in this state, the chuck means 3 of the upper driving device 4 chucks the rotary shaft 6, and the chuck means 3 of the lower driving device 5 chucks the rotary shaft 6. Not And Lee ,, Next, the rotary shaft 6 rotational driving force to the rotating shaft 6 through the chuck means 3 is transmitted by rotating the rotating device 10 of the upper drive unit 4 is rotated,
In this way, while rotating the rotary shaft 6, the upper drive device 4 is lowered along the reader 2 to excavate the ground 7 by the rotary shaft 6, and the lower drive device 5 that is free with respect to the rotary shaft 6 is 2 may be moved to the upper limit position of the moving range, and in the state of FIG. 9, the chuck shaft 3 is chucked by the chuck means 3 of the upper drive unit 4 and the chuck of the lower drive unit 5 at the same time. Means 3
The lower drive device 5 and the rotary shaft 6 are released by releasing the chuck by the above, the rotary shaft 6 is lifted together with the upper drive device 4, and the lower drive device 5 which is free with respect to the rotary shaft 6 is moved within its moving range. 12 may be moved to the lower limit position of FIG. 12, and by returning to this FIG. 12, the process returns to the first stage shown in FIG.

Here, the reason shown in FIGS. 1 and 9 is to prevent the stirring unit 25 from interfering with the lower drive unit 5 when the stirring unit 25 is provided below the rotary shaft 6. . Therefore, when the stirring portion 25 is not provided in the lower portion, it can be configured as shown in FIGS.
Further, in the excavation start stage of FIG. 1, the excavation may be started by chucking and lowering the rotary shaft 6 in a state where the lower drive device 5 is positioned in the vertical position of the vertical movement range. is there. In this case, the upper drive unit 5 may be located at the upper limit position or the lower limit position of its vertical movement range in advance, but when it is located at the lower limit position, the lower drive unit 5 may be located. The upper drive device 5, which has become free with respect to the rotary shaft 6 when the lower part is lowered, is allowed to rise.

When the rotary shaft 6 is pulled up, the rotary shaft 6 may be pulled up by a wire without the upper drive device 4 and the lower drive device 5 being chucked to the rotary shaft 6. The ground 7 is excavated as described above. When the rotary shaft 6 is inserted into the ground 7 for excavation, or when the rotary shaft 6 is pulled up, or when the rotary shaft 6 is inserted or pulled up, the cement is removed from the rotary shaft 6. Drilling while injecting a solidifying material such as milk, stirring and mixing the excavated earth and solidifying material and filling the mixture of the excavated earth and solidifying material into the excavation hole to improve the ground, or improve A pillar can be formed. Moreover, the earth retaining wall can be formed by continuously forming the improved columns.

[0028]

As described above, according to the present invention, the upper drive device provided with the chuck means and the lower drive device provided with the chuck means can be moved up and down on the reader erected on the apparatus main body. Attaching and rotating the rotary shaft equipped with excavating means at the lower end with the chuck means provided in the lower drive device releasing the chuck with the rotary shaft chucked by the upper drive device. The rotary drive force of the upper drive unit is transmitted to the rotary shaft so that the shaft does not move in the vertical direction, and in this state, the rotary shaft is lowered along with the upper drive unit along the leader, and the ground is drilled with the rotary shaft. Then, after lowering the upper drive unit by an arbitrary length, the lower drive unit is rotated by chucking the rotary shaft by the chuck means of the lower drive unit so that the rotary shaft does not move vertically with respect to the lower drive unit. While transmitting power to the rotary shaft,
The chuck of the rotary shaft by the chuck means of the upper drive device is released, and in this state, the rotary shaft is lowered along with the lower drive device along the leader, the ground is drilled by the rotary shaft, and the lower drive device is lowered. At the same time, the upper drive device is raised along the leader, and then, when the lower drive device is lowered by an arbitrary length and the upper drive device is raised by an arbitrary length, the rotating shaft is chucked by the chuck means of the upper drive device. The rotary drive force of the upper drive device is transmitted to the rotary shaft so that the rotary shaft does not move vertically with respect to the upper drive device, and the chucking of the rotary shaft by the chuck means of the lower drive device is released. In this state, the rotary shaft is lowered along with the upper drive unit along the leader, and the ground is drilled by the rotary shaft, and the lower drive unit is simultaneously raised along the leader while the upper drive unit is descending. Since the ground is excavated by repeating the above steps, it is not necessary to connect the upper end portion of the rotary shaft to the drive device for imparting rotation to the rotary shaft, and the upper drive device and the lower drive device, which are heavy, are located at the lowest possible position. It is possible to lower the center of gravity of the device as a whole, and as a result, it is possible to prevent the device from falling, and both the upper drive device and the lower drive device are attached to the rotating shaft by the chuck means. Since it can move with respect to the conventional rotation shaft by chucking it so that it does not move in the vertical direction and transmitting the rotational driving force, and it becomes free when the chuck is released by the chuck means. The horizontal axis is not limited to a non-circular horizontal axis such as the one that transmits rotational torque while allowing movement in any direction. Those capable of transmitting rotational driving force to the chuck rotational axis by click means. Further, when the rotary shaft is chucked by the chuck means provided in the upper drive unit and the lower drive unit, the rotary shaft is chucked so as not to move up and down, so when the upper drive unit or the lower drive unit is lowered in the chucked state. To
The load of the drive device can be pushed into the ground while being applied to the rotary shaft, and it is not necessary to provide a separate hydraulic jack for pushing the rotary shaft into the ground as in the conventional case.

Further, in the invention according to claim 2, the reader provided on the main body of the apparatus, the upper drive device and the lower drive provided on the reader so as to be movable up and down and repeatedly moved in a direction toward each other and a direction away from each other. Device, and a rotating shaft having excavation means provided at the lower end portion that is alternately rotated by the upper driving device and the lower driving device, and a chuck capable of transmitting the rotational driving force to the rotating shaft only in the chuck state in the upper driving device. Means
Since the lower drive unit is provided with the chuck means capable of transmitting the rotational driving force to the rotary shaft only in the chucked state, it can be used for a fixed center of gravity and also for the rotary shaft having a horizontal or circular cross section. It is possible to provide an excavator that can be loaded into the ground by applying the load of the upper drive unit or the lower drive unit to the rotary shaft when inserting the rotary shaft.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an order of performing insertion of a rotary shaft of the present invention.

FIG. 2 is an explanatory diagram showing an execution order of the above.

FIG. 3 is an explanatory diagram showing an enforcement order of the above.

FIG. 4 is an explanatory diagram showing an execution order of the above.

FIG. 5 is an explanatory diagram showing an enforcement order of the above.

FIG. 6 is an explanatory view showing a procedure for pulling up the rotary shaft of the above.

FIG. 7 is an explanatory diagram showing an enforcement order of the above.

FIG. 8 is an explanatory diagram showing an execution order of the above.

FIG. 9 is an explanatory diagram showing an enforcement order of the above.

FIG. 10 is an explanatory diagram showing an enforcement order of the above.

FIG. 11 is an explanatory diagram showing another enforcement method of the present invention.

FIG. 12 is an explanatory diagram showing another enforcement method of the above.

FIG. 13 is an upper drive device (lower drive device) used in the same as above.
It is a schematic front view of the chuck means provided in FIG.

FIG. 14 is an upper drive device (lower drive device) used in the same as above.
It is a schematic perspective view of the chuck means provided in FIG.

[Explanation of symbols]

 1 Device Main Body 2 Reader 3 Chuck Means 4 Upper Drive Device 5 Lower Drive Device 6 Rotation Axis 7 Ground

Claims (2)

[Claims] 1. A rotary shaft having an upper drive unit equipped with a chuck unit and a lower drive unit equipped with a chuck unit, which is vertically movably mounted on a reader provided upright on the main body of the apparatus, and a drilling unit provided at a lower end thereof. While the chuck is released by the chuck means provided in the lower drive device, the upper drive device is chucked by the chuck means of the upper drive device so that the rotary shaft does not move vertically with respect to the upper drive device. The rotational driving force of the device is transmitted to the rotary shaft, and in this state, the rotary shaft is lowered along with the upper drive device along the leader, the ground is drilled by the rotary shaft, and the upper drive device is lowered by an arbitrary length. After that, the chuck means of the lower drive unit chucks the rotary shaft so that the rotary shaft does not move in the vertical direction with respect to the lower drive unit, and the rotary drive force of the lower drive unit is transmitted to the rotary shaft. The chuck of the rotary shaft by the chuck means of the drive unit is released, and in this state, the rotary shaft is lowered along with the lower drive unit along the leader, the ground is drilled by the rotary shaft, and the lower drive unit is lowered. At the same time, the upper drive device is raised along the leader, and then, when the lower drive device is lowered by an arbitrary length and the upper drive device is raised by an arbitrary length, the rotating shaft is chucked by the chuck means of the upper drive device. The rotary drive force of the upper drive device is transmitted to the rotary shaft so that the rotary shaft does not move vertically with respect to the upper drive device, and the chucking of the rotary shaft by the chuck means of the lower drive device is released. In the state, the rotary shaft is lowered along with the upper drive unit along the leader, the ground is drilled by the rotary shaft, and the lower drive unit is simultaneously raised along the leader while the upper drive unit is descending. Ground excavation method characterized by drilling a ground by repeating serial steps. 2. A reader provided on the main body of the apparatus, an upper drive unit and a lower drive unit, which are provided on the reader so as to be vertically movable and which are repeatedly moved in a direction toward and away from each other, an upper drive unit and a lower drive unit. A rotating shaft having excavation means provided at the lower end which is alternately rotated by, the upper drive device is provided with chuck means capable of transmitting rotational drive force only to the rotating shaft in the chuck state, and the lower drive device is provided in the chuck state. A ground excavating device comprising a chuck means capable of transmitting a rotational driving force to a rotary shaft only.