JP2016113754A - Drilling machine and drilling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drilling machine suited for a reverse method and allowing a drilling device and a driving device to be separated readily from each other, along with a drilling method using the drilling machine.SOLUTION: A drilling machine includes a drilling device and a driving device. The driving device includes a main frame; a hollow driving shaft disposed relatively rotatably on the main frame; a drive unit having a drive motor and fixed on the main frame for rotating the hollow driving shaft; and a lift pump connected relatively rotatably on an end of the hollow driving shaft and having a suction port. The drilling device includes a hollow main shaft to be connected rotatably on the other end of the hollow driving shaft, to be rotated integrally with the hollow driving shaft, as well as at least one arm fitted on the main shaft, and a plurality of bits fitted on the at least one arm.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to an excavator and a excavation method using the excavator.

An all casing method is known as one of methods for excavating holes for cast-in-place piles. In the all-casing method, after the casing is press-fitted into the ground, the earth and sand in the casing is discharged out of the casing using a hammaglab, a drilling bucket, or the like.
And in order to improve the bearing capacity of a cast-in-place pile, forming a bottom-up part in the lower end part of a hole is performed. As an excavator capable of forming an expanded bottom portion, an excavator capable of changing the rotation radius of a bit around the axis of a hole is known.

  For example, the excavator disclosed in Patent Document 1 includes a bottom expansion bucket and a drive device. The bottom end side surface of the hole can be excavated by rotating the bottom expansion bucket while the widening blade of the bottom expansion bucket is opened. And after closing a widening blade and accommodating earth and sand in a bottom expansion bucket, earth and sand can be discharged | emitted out of a hole by taking out a bottom expansion bucket out of a hole. In addition, a hole wall can be protected by supplying a bendnite solution (stabilizing liquid) to the bottom of the hole when excavating the bottom.

  Here, the excavator drive device disclosed in Patent Document 1 has a chuck device that can fix the drive device to the casing. For this reason, according to this excavator, excavation with high torque and high rotation speed is possible.

On the other hand, a reverse construction method is known as one of methods for excavating holes for cast-in-place piles. In the reverse method, the bendnite solution is injected into the hole being excavated, while the mud containing the excavated earth and sand is discharged out of the hole by a pump, and the hole is dug down by an excavator.
For example, an excavator disclosed in Patent Document 2 includes a bit rotatably supported by a fixed pipe, a submersible sand pump fixed to the fixed pipe, and hydraulic motors installed on both sides of the fixed pipe. . According to this excavator, the muddy water containing the earth and sand excavated by the bit is sucked from the lower end inlet of the fixed pipe and sent out to the ground by the submersible sand pump.

And also in the case of using a reverse construction method similarly to the case of the all casing construction method, in order to improve the supporting force of a cast-in-place pile, forming a bottom expanded part in the lower end part of a hole is performed.
For example, an excavator disclosed in Patent Document 3 has a cutter shaft provided obliquely to a fixed pipe, and the cutter is attached to the cutter shaft. When the cutter shaft is constituted by a cylinder, the rotation radius of the cutter around the fixed pipe can be changed according to the expansion and contraction of the cylinder.
Further, for example, in the excavator disclosed in Patent Document 4, the rotation radius of the drum cutter around the fixed pipe (main shaft) can be changed by rotating a plurality of arms.

JP 2014-114543 A JP 2007-146514 A JP 2007-262820 A JP 2013-36178 A

When excavating a hole with the excavator disclosed in Patent Document 1, since there is no mechanism for discharging excavated soil, the excavator is once lifted to the ground, and then a bucket or the like is inserted into the hole. Excavated soil will be discharged. In this case, since a part of excavated soil leaks from the bucket or the like together with the muddy water, work efficiency is lowered.
In the method of discharging excavated soil using a bucket or the like, slime is accumulated at the lower end of the hole. Since slime reduces the bearing capacity of cast-in-place piles, it must be removed before placing concrete, but when waiting for slime to accumulate at the lower end of the hole, the waiting time is long. The construction period will be longer.
In this respect, if the reverse construction method is used, mud water is discharged from the hole using the drain pipe, so that slime adhesion to the inner peripheral surface of the casing can be suppressed. For this reason, the slime removal operation can be performed in a short time.

On the other hand, in the excavator disclosed in Patent Document 3 applicable to the reverse construction method, the lower end side of the main shaft supports the outer shaft of the revolving part through a bearing so as to be able to revolve, and between the main shaft and the revolving part The connection structure is complicated. For this reason, excavators frequently break down and are difficult to repair on site. In addition, the main shaft and cutter are integrally formed, and the main shaft and cutter cannot be separated and handled separately, so the excavator becomes long, and workability when inserting into the hole and lifting from the hole There is a problem that is bad.
These problems exist not only in the excavator disclosed in Patent Document 3, but also in the excavator disclosed in Patent Document 4.

Furthermore, the excavator disclosed in Patent Document 3 has a guide for maintaining the vertical posture of the excavator, but does not have a chuck device for fixing the excavator to the casing. Therefore, when the excavator disclosed in Patent Document 3 is used, the rotational reaction force during excavation must be received through the drain pipe. For this reason, the excavator disclosed in Patent Document 3 has a problem that it is not suitable for excavation at a high torque or a high rotation speed, particularly when the hole is deep.
These problems exist not only in the excavator disclosed in Patent Document 3, but also in the excavators disclosed in Patent Document 1 and Patent Document 2.

  In addition, the excavator disclosed in Patent Document 2 has a problem that the bottom end of the hole cannot be expanded and excavated.

In view of the above circumstances, an object of at least one embodiment of the present invention is to provide an excavator that can be easily separated from an excavator and a drive device while being suitable for a reverse method, and an excavation method using the excavator. There is.
In addition, an object of at least one embodiment of the present invention is to provide an excavator that is suitable for excavation at high torque while being suitable for the reverse method, and an excavation method using the excavator.

(1) An excavator according to at least one embodiment of the present invention includes:
In an excavator that includes a drilling device for excavating the ground and a driving device that drives the drilling device, and drills a hole by a reverse method,
The driving device includes:
The mainframe,
A hollow drive shaft provided rotatably relative to the main frame;
A drive unit having a drive motor and fixed to the main frame for rotating the hollow drive shaft;
A pump including a suction port connected to one end of the hollow drive shaft via a swivel joint so as to be relatively rotatable,
The drilling rig is
A hollow main shaft that is detachable from the other end of the hollow drive shaft and rotates integrally with the hollow drive shaft;
An arm having one end rotatably attached to the main shaft;
A tilting actuator provided between the main shaft and the arm, for tilting the arm radially outward of the main shaft;
A plurality of bits attached to the arm;
A tip cutter provided on the tip side of the main shaft;
A rotary joint interposed between the main shaft and the hollow drive shaft and having a flow path for supplying a working fluid to the tilting actuator.

In the configuration (1), the pumping pump and the hollow drive shaft are connected to each other so as to be relatively rotatable in the drive device, and the hollow drive shaft of the drive device and the main shaft of the excavator are integrally connected. In this configuration, since the hollow drive shaft and the main shaft can rotate integrally, the hollow drive shaft and the main shaft can be coupled with a simple connection configuration. For this reason, the drive device and the excavator can be easily separated and handled.
Moreover, the hollow drive shaft has a swivel joint on one end side, and the suction port of the pump and the hollow drive shaft are connected by the swivel joint so as to be relatively rotatable. By connecting the suction port of the pump and the hollow drive shaft so as to be relatively rotatable by a swivel joint, the hollow drive shaft and the main shaft can be rotated integrally without rotating the pump.
By connecting the main shaft and the hollow drive shaft via a rotary joint having a flow path for supplying the working fluid, the working fluid can be reliably supplied to the tilting actuator with a simple configuration.

(2) In some embodiments, in the configuration (1),
The driving device includes:
A first projecting member projecting radially outward of the hollow drive shaft from the main body of the pump;
A first stopper member fixed to the main frame and capable of contacting the first projecting member in a rotation direction of the hollow drive shaft.

  In the configuration (2), even if the pump is rotatable relative to the hollow drive shaft, the pump is rotated with the rotation of the hollow drive shaft by the first projecting member coming into contact with the first stopper member. It is prevented.

(3) In some embodiments, in the configuration (1) or (2),
The drilling rig is
A second projecting member projecting radially outward of the hollow drive shaft from the rotary joint;
A second stopper member provided so as not to rotate relative to the main frame and capable of contacting the second projecting member in the rotation direction of the hollow drive shaft;
Is further included.

  In the configuration (3), even if the rotary joint has a movable side that rotates together with the hollow drive shaft and the main shaft, the stationary side of the rotary joint is hollow by the second projecting member coming into contact with the second stopper member. Rotation with the rotation of the drive shaft is prevented.

(4) In some embodiments, in any one of the configurations (1) to (3),
The hollow drive shaft has a spline joint on the other end side.

  In the configuration (4), the hollow drive shaft and the rotary joint are coupled together via the spline joint so as to be rotatable together. When a spline joint is used, it is possible not only to connect the hollow drive shaft and the main shaft more easily than when using a flange connection, but also to transmit high torque with a small cross-sectional area. For this reason, even if the hollow drive shaft and the main shaft become long, that is, even if the entire length of the excavator becomes long, high torque can be transmitted to the tip of the excavator.

(5) In some embodiments, in any one of the configurations (1) to (4),
The drive unit has a driven gear capable of transmitting the output of the drive motor to the hollow drive shaft,
The swivel joint is provided on the hollow drive shaft closer to the pump than the driven gear.

  In the above configuration (5), the mounting portion of the swivel joint and the driven gear is separately provided on the hollow drive shaft, so that the configuration of the hollow drive shaft can be simplified.

(6) In some embodiments, in any one of the above configurations (1) to (5),
The driving device includes:
A plurality of contact members arranged in the circumferential direction of the hollow drive shaft and movable in the radial direction of the hollow drive shaft;
A fixing actuator fixed to the main frame and configured to move the plurality of contact members in a radial direction of the drive shaft;

In the configuration (6), the drive device can be fixed to the hole wall or the casing via the contact member by moving the contact member radially outward by the fixing actuator. As a result, the hole wall and casing around the drive device can receive the rotational reaction force of the excavator, and excavation at high torque or high rotation speed is possible.
In particular, when the bottom portion is provided in the hole, it is desirable that the shape and size of the bottom portion is as designed in consideration of ensuring the support strength and the amount of concrete used. In this regard, according to the above configuration (6), the hole wall and the casing receive the rotational reaction force of the excavator, so that the attitude of the excavator is stabilized and the shape and size of the expanded bottom portion can be made as designed. it can.

(7) In some embodiments, in any one of the configurations (1) to (6),
The driving device includes:
A movable frame provided closer to the excavator than the main frame, and movable in the axial direction of the hollow drive shaft with respect to the main frame;
One end is fixed to the main frame, the other end is fixed to the movable frame, and an urging actuator for moving the movable frame relative to the main frame in the axial direction of the hollow drive shaft;
And a bearing that is detachably attached to the movable frame and rotatably supports the hollow drive shaft.

In the configuration (7), the excavator can be urged toward the ground by moving the movable frame by the urging actuator, thereby increasing the digging capability.
In addition, since the bearing is provided closer to the excavator than the main frame, the shaft center of the hollow drive shaft can be prevented from shaking. Thereby, the shape and size of the hole can be made as designed.
And since the bearing is detachable, it can be easily replaced when worn.

(8) In some embodiments, in the configuration (7),
The driving device includes:
A guide unit for guiding the movement of the movable frame in the axial direction of the hollow drive shaft is further included.

  In the configuration (8), since the guide unit guides the movement of the movable frame in the axial direction of the hollow drive shaft, the movable frame and the hollow drive shaft are moved by the reaction force when the movable frame is biased by the biasing actuator. It is prevented from being twisted or tilted with respect to the main frame. For this reason, it is possible to prevent the excavator from being inclined and to dig the hole straight.

(9) In some embodiments, in any one of the configurations (1) to (8),
A tank capable of storing the working fluid supplied to the tilting actuator;
A sensor capable of outputting a signal corresponding to the amount of the working fluid stored in the tank;
And a control device configured to obtain a tilt amount of the arm with respect to the main shaft based on an output signal of the sensor and to display the obtained tilt amount.

  In the configuration (9), the control device can accurately determine the tilt amount based on the sensor and displays the calculated tilt amount, so that the operator can quickly know the correct tilt amount. it can. Considering the support strength and the amount of concrete used, it is desirable that the shape and size of the bottom expansion part is as designed, and the operator can set the shape and size of the bottom expansion part as designed based on the exact amount of tilting. Can be.

(10) A hole excavation method according to at least one embodiment of the present invention includes:
An excavation method for excavating a hole by a reverse method using an excavator provided with an excavator for excavating the ground and a drive device for driving the excavator,
The driving device includes:
The mainframe,
A hollow drive shaft provided rotatably relative to the main frame;
A drive unit having a drive motor and fixed to the main frame for rotating the hollow drive shaft;
A pump including a suction port connected to one end of the hollow drive shaft via a swivel joint so as to be relatively rotatable,
The drilling rig is
A hollow main shaft that is detachable from the other end of the hollow drive shaft and rotates integrally with the hollow drive shaft;
An arm having one end rotatably attached to the main shaft;
A tilting actuator provided between the main shaft and the arm, for tilting the arm radially outward of the main shaft;
A plurality of bits attached to the arm;
A tip cutter provided on the tip side of the main shaft;
A rotary joint interposed between the main shaft and the hollow drive shaft and having a flow path for supplying a working fluid to the tilting actuator,
An insertion step of inserting the excavator into a lower end portion in a hole of the same diameter formed in the ground;
Connecting the drainage pipe for discharging the muddy water in the hole to the drive device to the pump;
The excavator is driven by the driving device while supplying a stable liquid into the hole and discharging muddy water in the hole, and the lower end of the hole is excavated by the tip cutter without tilting the arm. And excavation process for excavating with the same diameter,
Is provided.

In the above configuration (10), since the swivel joint and the rotary joint are respectively provided at both ends of the hollow drive shaft of the drive device, it can be easily separated from the pump and the excavator at these positions. As a result, since the drive device and the excavator can be handled separately, the workability of the work of inserting into the hole of the excavator and the work of extracting from the hole is improved.
Further, the hollow drive shaft of the drive device and the main shaft of the excavator are integrally connected. Thereby, since the excavator can be directly rotated by the hollow drive shaft, the overall length of the excavator can be shortened. And since excavator full length can be shortened, it can excavate with high torque.
Furthermore, the arm that is not tilted, that is, the arm that is closed, has a function as a guide for guiding the earth and sand excavated by the tip cutter to the lower end of the hollow drive shaft, so that the excavated earth and sand can be discharged efficiently. it can.

(11) A hole excavation method according to at least one embodiment of the present invention includes:
An excavation method for excavating a hole by a reverse method using an excavator provided with an excavator for excavating the ground and a drive device for driving the excavator,
The driving device includes:
The mainframe,
A hollow drive shaft provided rotatably relative to the main frame;
A drive unit having a drive motor and fixed to the main frame for rotating the hollow drive shaft;
A pump including a suction port connected to one end of the hollow drive shaft via a swivel joint so as to be relatively rotatable,
The drilling rig is
A hollow main shaft that is detachable from the other end of the hollow drive shaft and rotates integrally with the hollow drive shaft;
An arm having one end rotatably attached to the main shaft;
A tilting actuator provided between the main shaft and the arm, for tilting the arm radially outward of the main shaft;
A plurality of bits attached to the arm;
A tip cutter provided on the tip side of the main shaft;
A rotary joint interposed between the main shaft and the hollow drive shaft and having a flow path for supplying a working fluid to the tilting actuator,
An insertion step of inserting the excavator into a lower end portion in a hole of the same diameter formed in the ground;
Connecting the drainage pipe for discharging the muddy water in the hole to the drive device to the pump;
While supplying the stabilizing liquid into the hole and discharging the muddy water in the hole, the excavator is driven by the drive device, and the arm attached to the arm in a tilted state is used. A bottom expanding step of excavating a lower end side surface of the hole to form a bottom expanded portion having a hole diameter larger than the same diameter;
Is provided.

In the above configuration (11), since the swivel joint and the rotary joint are respectively provided at both ends of the hollow drive shaft of the drive device, it can be easily separated from the pump and the excavator at these positions. As a result, since the drive device and the excavator can be handled separately, the workability of the work of inserting into the hole of the excavator and the work of extracting from the hole is improved.
Further, the hollow drive shaft of the drive device and the main shaft of the excavator are integrally connected. Thereby, since the excavator can be directly rotated by the hollow drive shaft, the overall length of the excavator can be shortened. And since excavator full length can be shortened, it can excavate with high torque.
Further, when the excavator is rotated with the arm tilted, a centrifugal force acts on the arm, so that the arm can be easily expanded. And since an arm rotates centering | focusing on the main axis | shaft of a digging apparatus, the uniform substantially conical bottom expansion part can be formed. Thereby, the load which acts on a pile can be supported uniformly by the whole widened part, and since the concentrated load does not act on a specific location, damage etc. of a pile can be prevented.

(12) In some embodiments, in the configuration (11),
Between the connecting step and the bottom expanding step,
While supplying the stabilizing liquid into the hole and discharging the muddy water in the hole, the excavator is driven by the driving device, and the lower end of the hole is excavated by the tip cutter to have the same diameter. A drilling process is also provided.

  In the configuration (12), after the excavation process, it is possible to continuously shift to the bottom expansion process without performing the operation of lifting the excavator to the ground and the operation of inserting the bottom expansion excavator into the hole. Thereby, the working time can be greatly shortened.

(13) In some embodiments, in any one of the configurations (10) to (12),
The driving device includes:
A plurality of contact members arranged in the circumferential direction of the hollow drive shaft and movable in the radial direction of the hollow drive shaft;
A fixing actuator fixed to the main frame and configured to move the plurality of contact members in a radial direction of the drive shaft;
Is further provided,
After the connecting step,
The drive device supports the rotational reaction force during excavation by the excavator by bringing the contact member into close contact with the hole wall or casing of the hole by the fixing actuator.

In the configuration (13), the excavator is driven by the driving device fixed to the hole wall or the casing, so that the hole wall or the casing can receive the rotational reaction force of the excavator, and the bottom portion is expanded with high torque. Can be excavated.
In addition, considering the support strength and the amount of concrete used, it is desirable that the shape and size of the expanded bottom part be as designed. In this regard, according to the above configuration (13), the hole wall and casing around the drive device receive the rotational reaction force of the excavator, so that the attitude of the excavator is stabilized and the shape and size of the bottom expansion portion are designed. Can be on the street.

(14) In some embodiments, in any one of the configurations (10) to (12),
The excavator is
The drainage pipe is further connected to the drainage pipe and is rotatable about the central axis of the drainage pipe, and further includes a turning device fixed to the ground.
In the connecting step,
The drain pipe is connected to the rotation device, and the rotation reaction force during excavation by the excavator is supported by the rotation device.
In the configuration (14), the rotational reaction force of the excavator can be received by the rotating device.

According to at least one embodiment of the present invention, there is provided an excavator that is suitable for the reverse method and can easily separate the excavator and the drive device, and an excavation method using the excavator.
In addition, according to at least one embodiment of the present invention, an excavator suitable for a reverse torque method and suitable for excavation at high torque and an excavation method using the excavator are provided.

It is sectional drawing which shows roughly the drive device which concerns on one Embodiment of this invention, and is schematic sectional drawing of a drive device when the hydraulic cylinder of an urging | biasing unit is an expansion | extension state. It is sectional drawing which shows schematically the drive device which concerns on one Embodiment of this invention, and is schematic sectional drawing of a drive device when the hydraulic cylinder of a biasing unit is a shortened state. It is a side view which shows roughly the excavation apparatus which concerns on one Embodiment of this invention in a partial cross section, and is a side view which shows an excavation apparatus when the movable arm exists in the state which is not tilting. It is a side view which shows roughly the excavation apparatus which concerns on one Embodiment of this invention in a partial cross section, and is a side view which shows an excavation apparatus when a movable arm exists in the position for an expanded bottom part excavation. It is a block diagram which shows roughly the structure of the tilting amount control system for controlling the tilting amount of the movable arm of an excavator. FIG. 4 is a schematic cross-sectional view taken along line VI-IV in FIG. 1. It is a flowchart which shows roughly the procedure of the hole excavation method which concerns on at least 1 embodiment of this invention. It is a figure for demonstrating a casing press injection process. It is a figure for demonstrating an excavation process. It is a figure for demonstrating a raising process and an insertion process. It is a figure for demonstrating a fixing process. It is a figure for demonstrating a bottom expansion process. It is a figure for demonstrating the shape of the hole which has a shaft part and an expanded bottom part. It is a flowchart which shows roughly the procedure of the hole excavation method which concerns on some embodiment. It is a figure for demonstrating a shaft part upper side excavation process. It is a figure for demonstrating a drilling apparatus insertion process. It is a figure for demonstrating a shaft part upper side excavation process. It is a figure for demonstrating a bottom expansion process. It is a flowchart which shows roughly the procedure of the hole excavation method which concerns on some embodiment. It is a figure for demonstrating a drilling apparatus insertion process and a shaft part lower side drilling process. It is a figure for demonstrating a bottom-expansion part excavator insertion process and a bottom-expansion process.

Hereinafter, some embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples. Absent.
For example, expressions expressing relative or absolute arrangements such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly In addition to such an arrangement, it is also possible to represent a state of relative displacement with an angle or a distance such that tolerance or the same function can be obtained.
For example, an expression indicating that things such as “identical”, “equal”, and “homogeneous” are in an equal state not only represents an exactly equal state, but also has a tolerance or a difference that can provide the same function. It also represents the existing state.
For example, expressions representing shapes such as quadrangular shapes and cylindrical shapes represent not only geometrically strict shapes such as quadrangular shapes and cylindrical shapes, but also irregularities and chamfers as long as the same effects can be obtained. A shape including a part or the like is also expressed.
On the other hand, the expressions “comprising”, “comprising”, “comprising”, “including”, or “having” one constituent element are not exclusive expressions for excluding the existence of the other constituent elements.

<First embodiment>
The excavator according to at least one embodiment of the present invention is used for excavation of a hole for cast-in-place pile, and is particularly suitable for the reverse method. The excavator includes a drilling device and a driving device.
1 and 2 are sectional views schematically showing a driving apparatus according to an embodiment of the present invention.

  As shown in FIG.1 and FIG.2, the drive device 1 has the main frame 2, the hollow drive shaft 3, the drive unit 4, and the sand pump 5 which is a pump. The main frame 2 includes, for example, a cylindrical main body 2a and annular flange portions 2b and 2c fixed concentrically to both ends of the main body 2a. The main body 2a and the flange portions 2b and 2c have a bobbin shape as a whole.

The hollow drive shaft 3 is provided to be rotatable relative to the main frame 2 and extends through the main bodies 2a, 2b and 2c of the main frame 2.
The drive unit 4 is fixed to the main frame 2 and is configured to rotate the hollow drive shaft 3. The drive unit 4 includes, for example, a gear box 6 fixed to the flange portion 2 b of the main frame 2 and at least one drive motor 7 fixed to the gear box 6. The drive motor 7 is, for example, a hydraulic motor, and can rotate the hollow drive shaft 3 via gears 17 and 18. In the present embodiment, for example, four drive motors 7 are arranged around the hollow drive shaft 3.

The sand pump 5 has a suction port 5a and a discharge port 5b, and the suction port 5a is connected to one end side of the hollow drive shaft 3 so as to be relatively rotatable. The discharge port 5 b is connected to the drain pipe 9 through the discharge pipe 8. The sand pump 5 is configured to suck mud containing the excavated soil in the hole being excavated through the hollow drive shaft 3 and discharge the mud out of the hole through the discharge pipe 8 and the drain pipe 9.
The hollow drive shaft 3 may be configured by a plurality of pipes connected to each other.

3 and 4 are side views schematically showing the excavation apparatus according to an embodiment of the present invention in a partial cross section.
As shown in FIGS. 3 and 4, the excavator 10 includes a main shaft 11, at least one movable arm 12, and a plurality of bits 13.
The main shaft 11 is hollow and can be connected to the other end side of the hollow drive shaft 3 so as to be rotatable integrally with the hollow drive shaft 3. At least one movable arm 12 is attached to the main shaft 11 so as to be integrally rotatable, and a plurality of bits 13 are attached to the at least one movable arm 12. The main shaft 11 may be constituted by a plurality of pipes connected to each other.

  In the above configuration, the sand pump 5 and the hollow drive shaft 3 are connected so as to be relatively rotatable in one drive device, and the hollow drive shaft 3 of the drive device 1 and the main shaft 11 of the excavating device 10 can be rotated together. It is connected. With this configuration, since the hollow drive shaft 3 and the main shaft 11 rotate integrally, the hollow drive shaft 3 and the main shaft 11 can be simply connected. Thereby, the drive device 1 and the excavation device 10 can be easily separated.

In some embodiments, as shown in FIGS. 1 and 2, the hollow drive shaft 3 has a swivel joint 15a on one end side. And the swivel joint 15b fitted so that relative rotation with respect to the swivel joint 15a is attached to the suction inlet 5a of a sand pump. The swivel joint 15a constitutes the swivel joint 15 together with the swivel joint 15b.
In this configuration, the hollow drive shaft 3 has a swivel joint 15a on one end side, and the suction port 5a of the sand pump 5 and the hollow drive shaft 3 are connected by the swivel joint 15 so as to be relatively rotatable. The suction port 5a of the sand pump 5 and the hollow drive shaft 3 are connected by a swivel joint 15 so as to be relatively rotatable.

Further, a first projecting member 20 projecting radially outward of the hollow drive shaft 3 from the main body of the sand pump 5, and fixed to the main frame 2, abuts on the first projecting member 20 in the rotational direction of the hollow drive shaft 3. A possible first stopper member 21 is provided.
The first stopper member 21 is formed longer than the amount of expansion / contraction of a biasing actuator 72 described later.

In this configuration, even if the sand pump 5 can rotate relative to the hollow drive shaft 3, the sand pump 5 is rotated with the rotation of the hollow drive shaft 3 by the first projecting member 20 coming into contact with the first stopper member 21. Is prevented from rotating.
The hollow drive shaft 3 and the main shaft 11 can be rotated integrally without rotating the sand pump 5.

The drive unit 4 includes a driven gear 17 that can transmit the output of the drive motor 7 to the hollow drive shaft 3. For example, the driven gear 17 constitutes a part of the gear box 6 and meshes with a drive gear 18 fixed to the output shaft of the drive motor 7.
The swivel joint 15 a is separated from the driven gear 17 in the axial direction of the hollow drive shaft 3. In this configuration, the mounting portion of the swivel joint 15a and the driven gear 17 is separately provided on the hollow drive shaft 3, so that the configuration of the hollow drive shaft 3 can be simplified.
The axial direction of the hollow drive shaft 3 is made to coincide with the vertical direction when the hole is excavated, and the excavator 10 is connected to the lower end of the hollow drive shaft 3.

As shown in FIGS. 3 and 4, the excavator 10 includes a hinge coupling portion 22 and at least one tilting actuator 23, while the excavator includes a rotary joint 25 as shown in FIGS. 1 and 2. Is further provided.
The hinge coupling portion 22 is provided between the main shaft 11 and the movable arm 12 and enables the movable arm 12 to tilt with respect to the main shaft 11. The tilting actuator 23 is provided between the main shaft 11 and the movable arm 12, and is configured to tilt the movable arm 12 with respect to the main shaft 11.

Here, FIG. 3 schematically shows the excavator 10 when the movable arm 12 is not tilted, and FIG. 4 shows the excavator when the movable arm 12 is at the bottom-excavation position. 10 is shown schematically.
When the movable arm 12 is not tilted, the movable arm 12 extends in the vicinity of the main shaft 11 in parallel with the main shaft 11, and the bit 13 attached to the movable arm 12 excavates the hole wall even if the main shaft 11 rotates. Not. However, the bottom of the hole can be excavated by rotating the 3-blade bit 50 (details will be described later).

  On the other hand, when the movable arm 12 is in the bottom-excavated portion excavation position, the movable arm 12 is inclined with respect to the main shaft 11, in other words, as it moves away from the hinge coupling portion 22 in the axial direction of the main shaft 11. The closer to, the farther away from the main shaft 11. The tip of the main shaft 11 is disposed on the lower side in the vertical direction when the excavator 10 is disposed in the hole. When the main arm 11 rotates when the movable arm 12 is in the bottom-extended portion excavation position, the periphery of the excavating device 10 is excavated by the bit 13 attached to the movable arm 12, and the frustoconical bottom-extended portion is formed at the lower end of the hole. Can be formed.

As shown in FIG. 1, the rotary joint 25 has an oil passage 25 a that is interposed between the main shaft 11 and the hollow drive shaft 3 and supplies hydraulic oil to the tilting actuator 23.
In this configuration, by connecting the main shaft 11 and the hollow drive shaft 3 via the rotary joint 25 having the oil passage 25a, the working oil can be reliably supplied to the tilting actuator 23 with a simple configuration.

  Specifically, oil tubes extending from the ground are respectively connected to the two hydraulic ports of the outer cylinder 25b of the rotary joint 25, and the oil extending from the tilting actuator 23 to the two hydraulic ports of the inner cylinder 25c of the rotary joint 25. Each tube is connected. The oil passage 25a is formed between the two hydraulic ports of the outer cylinder 25b and the two hydraulic ports of the inner cylinder 25c. Both ends of the inner cylinder 25c of the rotary joint 25 are connected to the hollow drive shaft 3 and the main shaft 11, respectively, and the outer cylinder 25b is fitted to the inner cylinder 25c so as to be relatively rotatable.

The driving device 1 further includes a second projecting member 54 and a second stopper member 55. The second projecting member 54 is fixed to the stationary side of the rotary joint 25, that is, the outer cylinder 25 b, and projects outward from the outer cylinder 25 b in the radial direction of the hollow drive shaft 3.
The second stopper member 55 is provided so as not to rotate relative to the main frame 2, and can contact the second projecting member 54 in the rotation direction of the hollow drive shaft 3. The second stopper member 55 is fixed to the flange portion 2b of the main frame 2, for example.
The second stopper member 55 is formed longer than the amount of expansion and contraction of a biasing actuator 72 described later.

  In this configuration, even if the rotary joint 25 has the movable side that rotates together with the hollow drive shaft 3 and the main shaft 11, that is, the inner cylinder 25 c, the second projecting member 54 contacts the second stopper member 55. The stationary side of the rotary joint 25 is prevented from rotating with the rotation of the hollow drive shaft 3.

  In some embodiments, as shown in FIGS. 1 and 2, the hollow drive shaft 3 has a spline joint portion 57 a on the other end side opposite to the sand pump 5. The spline joint part 57a is connected to the spline joint part 57b on the main shaft 11 side so as not to be relatively rotatable, and constitutes a hollow spline joint 57 together with the spline joint part 57b.

  In this configuration, the hollow drive shaft 3 and the main shaft 11 are connected to each other via the spline joint 57 so as to be integrally rotatable. When the spline joint 57 is used, it is possible not only to connect the hollow drive shaft 3 and the main shaft 11 more easily than to use flange connection, but also to transmit high torque with a small cross-sectional area.

FIG. 5 schematically shows a configuration of a tilt amount control system 30 for controlling the tilt amount of the movable arm 12 of the excavator 10. The tilt amount control system 30 includes a tank 31, an oil amount sensor 32, and a control device 34.
The tank 31 stores hydraulic oil supplied to the tilting actuator 23. The oil amount sensor 32 can output a signal corresponding to the amount of hydraulic oil in the tank 31, and is constituted by a liquid level gauge, for example. The tilting actuator 23 is, for example, a hydraulic cylinder 43.

  The control device 34 is configured by a computer, for example, and includes a tilt amount calculation unit 35 and a tilt amount display unit 36. The tilt amount calculation unit 35 can calculate the tilt amount of the movable arm 12 based on the output signal of the oil amount sensor 32. Specifically, the output signal of the oil amount sensor 32, that is, the amount of hydraulic oil stored in the tank 31 has a correlation with the amount of hydraulic oil supplied to the tilting actuator 23, that is, the expansion / contraction amount of the tilting actuator 23. There is also a correlation with the amount of tilting of the movable arm 12. An arithmetic expression or a data table representing a correlation between the output signal of the oil amount sensor 32 and the tilt amount of the movable arm 12 is input to the tilt amount calculating unit 35 in advance. The tilting amount of the movable arm 12 can be obtained from the output signal of the oil amount sensor 32 based on an arithmetic expression representing the relationship or a data table.

  The tilt amount display unit 36 is, for example, a computer monitor, and can display the tilt amount of the movable arm 12 calculated by the tilt amount calculation unit 35 by means of numerical values or graphics so that the operator can recognize it. .

  In this configuration, the control device 34 can accurately determine the tilt amount of the movable arm 12 based on the oil amount sensor 32 and also displays the determined tilt amount, so that the operator can accurately determine the tilt amount. You can know quickly. Considering the support strength and the amount of concrete used, it is desirable that the shape and size of the bottom expansion part is as designed, and the operator can set the shape and size of the bottom expansion part as designed based on the exact amount of tilting. Can be.

  The control device 34 further includes a tilt amount control unit 37. The tilt amount control unit 37 is configured to be able to control the tilt amount of the movable arm 12, and the calculated value of the tilt amount of the movable arm 12 obtained by the tilt amount calculating unit 35 is input by a worker, for example. The movable arm 12 can be tilted so as to approach the set value of the tilt amount of the arm 12.

  The tilting actuator 23 is a hydraulic cylinder 43, and a hydraulic pump 40 for supplying hydraulic oil and a control valve 41 are provided in an oil passage extending between the tank 31 and the tilting actuator 23. The control valve 41 is, for example, a four-direction two-position switching valve, and the amount of expansion / contraction of the hydraulic cylinder 43 can be controlled by the control valve 41. The tilt amount control unit 37 can bring the calculated value of the tilt amount of the movable arm 12 closer to the set value of the tilt amount of the movable arm 12 by controlling the operations of the hydraulic pump 40 and the control valve 41.

  The hydraulic cylinder 43 is arranged so that the expansion / contraction direction is parallel to the vertical direction when the excavator 10 is arranged in the hole, and the movable arm 12 is not tilted as shown in FIG. When the movable arm 12 is in the bottom-excavated position for excavation as shown in FIG. In this case, the cylinder tube 43 a of the hydraulic cylinder 43 is fixed to the main shaft 11, and the tip of the cylinder rod 43 b is fixed to the slider 45 slidably fitted to the main shaft 11. The slider 45 and the movable arm 12 are connected by a link rod 46.

  In some embodiments, the excavator 10 includes four movable arms 12 and four hydraulic cylinders 43, and the movable arms 12 and the hydraulic cylinders 43 are arranged around the main shaft 11 at 90 degree intervals.

The excavator 10 includes a cylindrical stabilizer 48 that is coaxially fixed to the proximal end side of the main shaft 11.
A tip cutter, a so-called three-blade bit 50 is attached to the tip side of the main shaft 11. The three-blade bit 50 includes three fixed arms 51 that are radially fixed to the distal end side of the main shaft 11 and a plurality of bits 52 that are attached to the fixed arm 51. When the movable arm 12 is not tilted, the rotation radius of the movable arm 12 around the main shaft 11 is smaller than the rotation radius of the three-blade bit 50. On the other hand, when the movable arm 12 is in the bottom-excavated portion excavation position, the rotational radius of the movable arm 12 around the main shaft 11 is larger than the rotational radius of the three-blade bit 50.

6 is a schematic cross-sectional view taken along the line VI-IV in FIG.
As shown in FIGS. 1, 2, and 6, the driving device 1 further includes a fixing unit 60 for fixing the position of the main frame 2 in the hole. The fixing unit 60 includes a plurality of contact members 61 and at least one fixing actuator 62.
The plurality of contact members 61 are arranged in the circumferential direction of the hollow drive shaft 3 and are movable in the radial direction of the hollow drive shaft 3. For example, four contact members 61 are arranged around the hollow drive shaft 3 at intervals of 90 degrees.
The fixing actuator 62 is fixed to the main frame 2 and can move the plurality of contact members 61 in the radial direction of the hollow drive shaft 3.

In this configuration, the contact member 61 can be moved radially outward by the fixing actuator 62. As shown in FIG. 6, when the wall surface of the hole around the driving device 1 is covered with the cylindrical casing 64, the contact member 61 is pressed against the inner peripheral surface of the casing 64, thereby The drive device 1 can be fixed. As a result, the casing 64 around the drive device 1 receives the rotational reaction force of the excavator 10 during excavation, and excavation with high torque is possible.
In particular, when the bottom portion is provided in the hole, it is desirable that the shape and size of the bottom portion is as designed in consideration of ensuring the support strength and the amount of concrete used. According to this configuration, since the casing 64 receives the rotational reaction force of the excavating device 10, the posture of the excavating device 10 is stabilized, and the shape and size of the expanded bottom portion can be made as designed.

In some embodiments, the contact member 61 includes a contact member main body 61a and a liner member 61b attached to the outer surface of the contact member main body 61a. The main frame 2 has an outer peripheral wall portion 2d fixed to the flange portion 2b, and the outer peripheral wall portion 2d has an opening through which the contact member 61 projects and sinks. Further, the main frame 2 has side wall portions 2 e that sandwich the contact member 61 from both sides in the circumferential direction of the hollow drive shaft 3.
The inner surface of the contact member main body 61a on the hollow drive shaft 3 side is formed by a tapered surface inclined with respect to the hollow drive shaft 3, and the tapered surface of the wedge member 65 is slidable on the taper surface of the contact member main body 61a. It is in contact. The wedge member 65 is provided so as to be movable along the hollow drive shaft 3.

The fixing actuator 62 is constituted by a hydraulic cylinder 66, and the expansion / contraction direction of the hydraulic cylinder 66 is parallel to the hollow drive shaft 3. The cylinder tube 66 a of the hydraulic cylinder 66 is fixed to the flange portion 2 c of the main frame 2, and the cylinder rod 66 b of the hydraulic cylinder 66 is connected to the wedge member 65. When the position of the wedge member 65 changes in the axial direction of the hollow drive shaft 3 due to the expansion and contraction of the hydraulic cylinder 66, the contact member 61 moves in the radial direction of the hollow drive shaft 3.
The fixed unit 60 includes four contact members 61 and four hydraulic cylinders 66. As shown in FIG. 6, the contact member 61 and the hydraulic cylinder 66 are arranged around the hollow drive shaft 3 at intervals of 90 degrees.

The drive device 1 further includes a biasing unit 70 that can bias the hollow drive shaft 3. The urging unit 70 further includes a movable frame 71, an urging actuator 72, and a bearing 73.
The movable frame 71 is movable in the axial direction of the hollow drive shaft 3 with respect to the main frame 2.
The urging actuator 72 is provided between the flange portion 2 b of the main frame 2 and the movable frame 71, and can move the movable frame 71 relative to the main frame 2 in the axial direction of the hollow drive shaft 3.
The bearing 73 is fixed to the movable frame 71 and rotatably supports the hollow drive shaft 3.

  In this configuration, the excavating apparatus 10 can be urged toward the hole bottom by moving the movable frame 71 by the urging actuator 72, thereby increasing the pressing force during excavation.

  The movable frame 71 has an annular shape, and is disposed so as to face the flange portion 2 c while being spaced apart from each other in the axial direction of the hollow drive shaft 3. The urging actuator 72 includes a hydraulic cylinder 75, and the expansion / contraction direction of the hydraulic cylinder 75 is parallel to the hollow drive shaft 3. The cylinder tube 75 a of the hydraulic cylinder 75 is fixed to the flange portion 2 c, and the tip of the cylinder rod 75 b of the hydraulic cylinder 75 is fixed to the movable frame 71. The movable frame 71 is connected to the flange portion 2c via a hydraulic cylinder 75, and the relative position of the movable frame 71 with respect to the main frame 2 changes in the axial direction of the hollow drive shaft 3 as the hydraulic cylinder 75 expands and contracts. To do.

On the other hand, the hollow drive shaft 3 passes through a bearing 73 fixed to the movable frame 71, and the bearing 73 rotatably supports the hollow drive shaft 3 and receives the thrust force of the hollow drive shaft 3. For this reason, the hollow drive shaft 3 can be displaced relative to the main frame 2 together with the movable frame 71 via the bearing 73, and the excavator 10 is biased toward the ground by extending the hydraulic cylinder 75. can do.
1 shows the drive device 1 when the hydraulic cylinder 75 is in the extended state, and FIG. 2 shows the drive device 1 when the hydraulic cylinder 75 is in the shortened state.

The drive device 1 further includes a guide unit 80 that guides the movement of the movable frame 71 in the axial direction of the hollow drive shaft 3.
In this configuration, since the guide unit 80 guides the movement of the movable frame 71 in the axial direction of the hollow drive shaft 3, the movable frame 71 and the main shaft are driven by the reaction force when the movable frame 71 is biased by the biasing actuator 72. 11 is prevented from tilting, and the hole can be dug straight.

In some embodiments, the guide unit 80 includes a guide rod 81 and a guide sleeve 82. The guide rod 81 extends in the axial direction of the hollow drive shaft 3 and penetrates the flange portion 2c. The guide sleeve 82 is fitted to the guide rod 81 and is fixed to the movable frame 71.
In some embodiments, as shown in FIG. 6, two guide rods 81 are spaced apart in the diameter direction of the hollow drive shaft 3, and two hydraulic cylinders 75 are arranged in the diameter direction of the hollow drive shaft 3. Are spaced apart from each other. The separation direction of the two guide rods 81 and the separation direction of the two hydraulic cylinders 75 are different by 90 degrees around the hollow drive shaft 3.

In order to allow relative displacement of the hollow drive shaft 3 with respect to the main frame 2, the hollow drive shaft 3 is provided with a key 3 a extending in the axial direction of the hollow drive shaft 3. The driven gear 17 is provided with a key groove (not shown) that extends in the axial direction of the hollow drive shaft 3 and engages with the key 3a. The hollow drive shaft 3 can be displaced in the axial direction with respect to the driven gear 17.
According to this configuration, since the key 3a extends in the axial direction, the key 3a and the key groove can be engaged even if the hollow drive shaft 3 is displaced in the axial direction, and the output of the drive motor 7 is driven hollow. It can be transmitted to the shaft 3.
When the urging unit 70 is not provided, the gear box 6 may be configured to receive the thrust force of the hollow drive shaft 3.

  In some embodiments, a plurality of struts 85 are provided around the sand pump 5. The column 85 extends in the axial direction of the hollow drive shaft 3, and a disk-shaped subframe 86 is fixed to the gear box 6 via the column 85.

A discharge pipe 8 and a drain pipe 9 are fixed to the subframe 86. The discharge pipe 8 is composed of a telescopic pipe 87 that can be expanded and contracted.
According to this configuration, even if the sand pump 5 is displaced in the axial direction together with the hollow drive shaft 3, the expansion tube 87 expands and contracts, so that the displacement of the hollow drive shaft 3 is not hindered.
Further, according to this configuration, when excavation is performed without fixing the main frame 2 to the casing 64 by the fixing unit 60, when receiving the reaction force of the excavator 10 by the drain pipe 9, the gear box 6, the column 85, and the sub A reaction force is transmitted to the drain pipe 9 through the frame 86. For this reason, it is possible to avoid a reaction force from acting on the sand pump 5.

FIG. 7 is a flowchart schematically showing a procedure of a hole excavation method according to at least one embodiment of the present invention. The hole excavation method can be implemented using, for example, the driving device 1 and the excavation device 10 illustrated in FIGS.
As shown in FIG. 7, the hole excavation method includes a casing press-fitting step S10, a excavation step S12, a pulling step S14, an insertion step S16, a connection step S18, a fixing step S20, and a bottom expansion step S22. ing.

  FIG. 8 is a diagram for explaining the casing press-fitting step S10. As shown in FIG. 8, in the casing press-fitting step S <b> 10, the cylindrical casing 64 having a plurality of bits at the tip is rotated, and the casing 64 is press-fitted into the ground. For the press-fitting, for example, an all-round rotary excavator 90 is used. And according to the depth of a hole, the some casing 64 is mutually connected and press-fitted in the ground. Installation of the all-round rotary excavator 90 on the ground and supply of the casing 64 to the all-round rotary excavator 90 are performed by, for example, a crawler crane 92.

FIG. 9 is a diagram for explaining the excavation step S12. As shown in FIG. 8, in the excavation step S <b> 12, the excavation object in the casing 64 is removed by the hammer magnet 93 to form the shaft portion 94 a of the hole. The operation of the hammer magnet 93 can also be performed by the crawler crane 92. The object to be excavated means ground soil and rocks, buried objects in the ground, existing structures and the like. The shaft portion 94a refers to a hole portion excavated with the same diameter.
In addition, although this embodiment demonstrated the case where the excavation target object was removed with the hammaglab 93, it is not limited to this, The drive device 1 and the excavation apparatus 10 are inserted, and the movable arm 12 tilts. Alternatively, the lower end of the hole 94 may be excavated by the three-blade bit 50 by driving the excavator 10 in the absence of the excavator 10. That is, this excavator is a combined excavator that can excavate a bottom hole and excavate a hole 94 of the same diameter with a desired length.

  FIG. 10 is a diagram for explaining the pulling step S14 and the inserting step S16. In the lifting step S <b> 14, the casing 64 is pulled up by the entire circumference rotary excavator 90 by the height corresponding to the depth of the expanded bottom portion to be formed. In the insertion step S <b> 16, the excavator 10 and the drive device 1 are inserted into the casing 64. When the excavator 10 and the drive device 1 are used, the excavator 10 and the drive device 1 can be connected with the excavator 10 fixed to the casing 64.

  In the connecting step S <b> 18, at least one drain pipe 9 for discharging the muddy water in the hole 94 is connected to the driving device 1.

  FIG. 11 is a diagram for explaining the fixing step S20. As shown in FIG. 11, in the fixing step S <b> 20, the excavation device 10 is lowered to the lower end portion of the shaft portion 94 a, and the driving device 1 is fixed to the casing 64. When the driving device 1 is used, the fixing device 60 can fix the driving device 1 to the casing 64.

  FIG. 12 is a diagram for explaining the bottom expanding step S22. As shown in FIG. 12, in the bottom expanding step S22, the excavator 10 is supplied by the driving device 1 fixed to the casing 64 while supplying the stabilizing liquid into the casing 64 and discharging the muddy water in the shaft portion 94a of the hole. Drive. As a result, the excavator 10 excavates the periphery of the lower end portion of the shaft portion 94a of the hole 94, thereby forming the expanded bottom portion 94b of the hole.

  When the driving device 1 is used, the muddy water can be discharged by the sand pump 5. The stable liquid can be supplied, for example, by sending the stable liquid stored in the circulation tank 98 installed on the ground into the casing 64 using the liquid feed pump 99. The discharged muddy water is filtered in the circulation tank 98 and then sent into the hole 94 again.

  FIG. 13 is a view for explaining the shape of the hole 94 having the shaft portion 94a and the expanded bottom portion 94b. When the excavator 10 is used, a truncated cone-shaped bottom expanded portion 94b is formed.

According to the hole excavation method described above, the casing 64 can receive the rotational reaction force of the excavating device 10 by driving the excavating device 10 by the driving device 1 fixed to the casing 64, and can expand the bottom with high torque. The portion 94b can be excavated.
Further, in view of ensuring the support strength and the amount of concrete used, it is desirable that the shape and size of the bottom expanded portion 94b be as designed. In this regard, according to the hole excavation method described above, the casing 64 around the drive device 1 receives the rotational reaction force of the excavation device 10, so that the attitude of the excavation device 10 is stabilized, and the shape and size of the expanded bottom portion 94 b are obtained. Can be as designed.

<Second embodiment>
FIG. 14 is a flowchart schematically showing a procedure of a hole excavation method according to some embodiments.
As shown in FIG. 14, the hole excavation method includes a casing press-fitting step S10, a shaft upper side excavation step S12, an insertion step S16, a connection step S18, a shaft lower side excavation step S21, and a bottom expansion step S22. I have.
Hereinafter, only contents different from the above-described embodiment will be described, and description of the same contents will be omitted.

FIG. 15 is a diagram for explaining the shaft portion upper excavation step S12.
As shown in FIG. 15, in the shaft portion upper excavation step S12 after the casing press-fitting step S10, the upper portion of the hole shaft portion 94a is removed by removing the object to be excavated in the casing 64 by the hammer magnet 93. Form.

FIG. 16 is a diagram for explaining the insertion step S16.
As shown in FIG. 16, in the insertion step S <b> 16, the excavation device 10 and the drive device 1 are inserted into the casing 64.

  In the connection step S <b> 18, the drain pipe 9 for discharging the muddy water in the casing 64 is connected to the driving device 1.

FIG. 17 is a diagram for explaining the shaft portion lower side excavation step S21.
As shown in FIG. 17, in the shaft portion lower excavation step S <b> 21, the excavator 10 is driven by the drive device 1 while supplying a stable liquid into the casing 64 and discharging muddy water in the shaft portion 94 a of the hole. Thereby, the lower end of the shaft portion 94a of the hole is excavated by the excavator 10.

Further, during excavation, the rotational reaction force of the excavator 10 is performed by restricting the rotation of the drain pipe 9. The rotation of the drain pipe 9 can be regulated by, for example, the reaction force table 100 attached to the upper end portion of the casing 64. The reaction force table 100 is configured to allow movement of the drain pipe 9 in the vertical direction while restricting rotation of the drain pipe 9. For this reason, the excavator 10 and the drive device 1 perform excavation in a state where the excavator 10 and the drive device 1 are suspended from the crawler crane 92 via the drain pipe 9.
Instead of the reaction force table 100, an all-around rotating device may be used. That is, a rotation device such as the reaction force table 100 or the entire circumference rotation device can be used to support the rotation reaction force during excavation by the excavator. The rotating device is connected to the drain pipe 9, can rotate the drain pipe 9 around the central axis of the drain pipe 9, and is fixed to the ground.

FIG. 18 is a diagram for explaining the bottom expanding step S22. When the excavator 10 can also excavate the bottom expanded portion, the bottom expanded step S22 can be executed following the shaft lower side excavating step S21.
As shown in FIG. 18, in the bottom expanding step S22, the excavator 10 is supplied by the driving device 1 fixed to the casing 64 while supplying the stabilizing liquid into the casing 64 and discharging the muddy water in the shaft portion 94a of the hole. Drive. Thus, the excavator 10 excavates the periphery of the lower end portion of the hole shaft portion 94a to form a hole widening portion 94b.
Thereby, the truncated cone-shaped widened portion 94b is formed.

In the hole excavation method described above, the excavation capability can be enhanced by temporarily energizing the excavator 10 downward with the drive device 1 in the shaft lower side excavation step S21.
Further, in the hole excavation method described above, the excavator 10 does not need to replace the excavator 10 after the shaft lower excavation step S21 by excavating the lower portion and the bottom expanded portion 94b of the hole shaft 94a. The widened bottom portion 94b of the hole can be easily formed.

<Third embodiment>
FIG. 19 is a flowchart schematically showing a procedure of a hole excavation method according to some embodiments. The hole excavation method in FIG. 19 is used when excavating the shaft portion 94a and the expanded bottom portion 96b with different excavating apparatuses.
In the hole excavation method of FIG. 19, as shown in FIG. 20, the excavator 102 in which the 3-blade bit 50 is fixed to the main shaft 11 is inserted in the shaft dedicated machine insertion step S <b> 33, and in the shaft lower side excavation step S <b> 37. Using the excavator 102, the lower side of the shaft portion 94a is excavated. The excavator 102 can excavate the shaft portion 94a, but does not have the movable arm 12 and cannot excavate the expanded bottom portion 94b.

  The excavator 102 is pulled out of the hole in the extraction step S39, and then, in the insertion step S16, the excavator 10 capable of excavating the expanded bottom portion 94b is inserted into the hole. And as shown in FIG. 21, the bottom expansion part 94b is excavated by the excavation apparatus 10 in bottom expansion process S22.

Also in the hole excavation method of FIG. 19, the excavation capability can be enhanced by temporarily energizing the excavator 102 downward by the drive device 1 in the shaft lower side excavation step S <b> 37.
On the other hand, in the hole excavation method of FIG. 19, the lower portion of the shaft portion 94 a is excavated by the excavator 102 and the bottom expanded portion 94 b is excavated by the excavator 10, so An excavator suitable for excavation of 94b can be used.

  Finally, the present invention is not limited to the above-described embodiments, and includes forms obtained by modifying the above-described embodiments and forms obtained by appropriately combining these forms.

DESCRIPTION OF SYMBOLS 1 Drive device 2 Main frame 2a Body 2b Flange part 2c Flange part 2d Outer peripheral wall part 2e Side wall part 3 Hollow drive shaft 3a Key 4 Drive unit 5 Sand pump 5a Suction port 5b Discharge port 6 Gear box 7 Drive motor 8 Discharge pipe 9 Drain Pipe 10 Excavator 11 Main shaft 12 Movable arm 13 Bit 15 Swivel joint 15a Swivel joint 15b Swivel joint 17 Driven gear 18 Drive gear 20 First protruding member 21 First stopper member 22 Hinge coupling portion 23 Tilt actuator 25 Rotary joint 25a Oil passage 25b Outer cylinder 26c Inner cylinder 30 Tilt amount control system 31 Tank 32 Oil amount sensor 34 Control device 35 Tilt amount calculation unit 36 Tilt amount display unit 37 Tilt amount control unit 40 Hydraulic pump 41 Control valve 43 Hydraulic cylinder 43a Cylinder tube 43b Cylinder Rod 45 Slider 46 Link rod 48 Stabilizer 50 Three blade bit 51 Fixed arm 52 Bit 54 Second projecting member 55 Second stopper member 57 Spline joint 57a Spline joint portion 57b Spline joint portion 60 Fixed unit 61 Contact member 61a Contact member main body 61b liner member 62 fixing actuator 64 casing 65 wedge member 66 hydraulic cylinder 66a cylinder tube 66b cylinder rod 70 biasing unit 71 movable frame 72 biasing actuator 73 bearing 75 hydraulic cylinder 75a cylinder tube 75b cylinder rod 80 guide unit 81 guide rod 81 82 Guide sleeve 85 Post 86 Subframe 87 Telescopic tube 90 All-around rotary excavator 92 Crawler crane 93 Hanmaglab 94 Hole 94a Shaft 94b Expansion Bottom 98 Circulation tank 99 Liquid feed pump 100 Reaction force table 102 Excavator

Claims (14)

In an excavator that includes a drilling device for excavating the ground and a driving device that drives the drilling device, and drills a hole by a reverse method,
The driving device includes:
The mainframe,
A hollow drive shaft provided rotatably relative to the main frame;
A drive unit having a drive motor and fixed to the main frame for rotating the hollow drive shaft;
A pump including a suction port connected to one end of the hollow drive shaft via a swivel joint so as to be relatively rotatable,
The drilling rig is
A hollow main shaft that is detachable from the other end of the hollow drive shaft and rotates integrally with the hollow drive shaft;
An arm having one end rotatably attached to the main shaft;
A tilting actuator provided between the main shaft and the arm, for tilting the arm radially outward of the main shaft;
A plurality of bits attached to the arm;
A tip cutter provided on the tip side of the main shaft;
A rotary joint that is interposed between the main shaft and the hollow drive shaft and has a flow path for supplying a working fluid to the tilting actuator;
Excavator characterized by including. The driving device includes:
A first projecting member projecting radially outward of the hollow drive shaft from the main body of the pump;
A first stopper member fixed to the main frame and capable of contacting the first projecting member in a rotation direction of the hollow drive shaft;
The excavator according to claim 1, further comprising: The drilling rig is
A second projecting member projecting radially outward of the hollow drive shaft from the rotary joint;
A second stopper member provided so as not to rotate relative to the main frame and capable of contacting the second projecting member in the rotation direction of the hollow drive shaft;
The excavator according to claim 1, further comprising:   The excavator according to any one of claims 1 to 3, wherein the hollow drive shaft has a spline joint portion on the other end side. The drive unit has a driven gear capable of transmitting the output of the drive motor to the hollow drive shaft,
The excavator according to any one of claims 1 to 4, wherein the swivel joint is provided on the hollow drive shaft closer to the pump than the driven gear. The driving device includes:
A plurality of contact members arranged in the circumferential direction of the hollow drive shaft and movable in the radial direction of the hollow drive shaft;
A fixing actuator fixed to the main frame and configured to move the plurality of contact members in a radial direction of the drive shaft;
The excavator according to any one of claims 1 to 5, further comprising: The driving device includes:
A movable frame provided closer to the excavator than the main frame, and movable in the axial direction of the hollow drive shaft with respect to the main frame;
One end is fixed to the main frame, the other end is fixed to the movable frame, and an urging actuator for moving the movable frame relative to the main frame in the axial direction of the hollow drive shaft;
A bearing detachably attached to the movable frame and rotatably supporting the hollow drive shaft;
The excavator according to any one of claims 1 to 6, further comprising: The driving device includes:
The excavator according to any one of claims 1 to 7, further comprising a guide unit that guides the movement of the movable frame in the axial direction of the hollow drive shaft. A tank capable of storing the working fluid supplied to the tilting actuator;
A sensor capable of outputting a signal corresponding to the amount of the working fluid stored in the tank;
A control device configured to obtain a tilt amount of the arm with respect to the main shaft based on an output signal of the sensor and to display the obtained tilt amount;
The excavator according to any one of claims 1 to 8, further comprising: An excavation method for excavating a hole by a reverse method using an excavator provided with an excavator for excavating the ground and a drive device for driving the excavator,
The driving device includes:
The mainframe,
A hollow drive shaft provided rotatably relative to the main frame;
A drive unit having a drive motor and fixed to the main frame for rotating the hollow drive shaft;
A pump including a suction port connected to one end of the hollow drive shaft via a swivel joint so as to be relatively rotatable,
The drilling rig is
A hollow main shaft that is detachable from the other end of the hollow drive shaft and rotates integrally with the hollow drive shaft;
An arm having one end rotatably attached to the main shaft;
A tilting actuator provided between the main shaft and the arm, for tilting the arm radially outward of the main shaft;
A plurality of bits attached to the arm;
A tip cutter provided on the tip side of the main shaft;
A rotary joint interposed between the main shaft and the hollow drive shaft and having a flow path for supplying a working fluid to the tilting actuator,
An insertion step of inserting the excavator into a lower end portion in a hole of the same diameter formed in the ground;
Connecting the drainage pipe for discharging the muddy water in the hole to the drive device to the pump;
The excavator is driven by the driving device while supplying a stable liquid into the hole and discharging muddy water in the hole, and the lower end of the hole is excavated by the tip cutter without tilting the arm. And excavation process for excavating with the same diameter,
A hole excavation method comprising: An excavation method for excavating a hole by a reverse method using an excavator provided with an excavator for excavating the ground and a drive device for driving the excavator,
The driving device includes:
The mainframe,
A hollow drive shaft provided rotatably relative to the main frame;
A drive unit having a drive motor and fixed to the main frame for rotating the hollow drive shaft;
A pump including a suction port connected to one end of the hollow drive shaft via a swivel joint so as to be relatively rotatable,
The drilling rig is
A hollow main shaft that is detachable from the other end of the hollow drive shaft and rotates integrally with the hollow drive shaft;
An arm having one end rotatably attached to the main shaft;
A tilting actuator provided between the main shaft and the arm, for tilting the arm radially outward of the main shaft;
A plurality of bits attached to the arm;
A tip cutter provided on the tip side of the main shaft;
A rotary joint interposed between the main shaft and the hollow drive shaft and having a flow path for supplying a working fluid to the tilting actuator,
An insertion step of inserting the excavator into a lower end portion in a hole of the same diameter formed in the ground;
Connecting the drainage pipe for discharging the muddy water in the hole to the drive device to the pump;
While supplying the stabilizing liquid into the hole and discharging the muddy water in the hole, the excavator is driven by the drive device, and the arm attached to the arm in a tilted state is used. A bottom expanding step of excavating a lower end side surface of the hole to form a bottom expanded portion having a hole diameter larger than the same diameter;
A hole excavation method comprising: Between the connecting step and the bottom expanding step,
While supplying the stabilizing liquid into the hole and discharging the muddy water in the hole, the excavator is driven by the driving device, and the lower end of the hole is excavated by the tip cutter to have the same diameter. The hole excavation method according to claim 11, further comprising an excavation step of excavating. The driving device includes:
A plurality of contact members arranged in the circumferential direction of the hollow drive shaft and movable in the radial direction of the hollow drive shaft;
A fixing actuator fixed to the main frame and configured to move the plurality of contact members in a radial direction of the drive shaft;
Is further provided,
After the connecting step,
13. The drive device according to claim 10, wherein the contact member is brought into close contact with the hole wall or casing of the hole by the fixing actuator to support a rotational reaction force during excavation by the excavator. The hole excavation method according to any one of the above. The excavator is
The drainage pipe is further connected to the drainage pipe and is rotatable about the central axis of the drainage pipe, and further includes a turning device fixed to the ground.
In the connecting step,
The hole according to any one of claims 10 to 12, wherein the drain pipe is connected to the rotating device, and a rotational reaction force during excavation by the excavator is supported by the rotating device. Drilling method.

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