JP3037609B2 - Drilling rig - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excavator having a down-the-hole hammer and mainly used for forming a foundation pile on a hard ground having a large amount of rock or rock on a flat ground. The present invention relates to an excavator capable of easily excavating the above-mentioned hard ground using a relatively small crane such as a column car or a backhoe type crane truck.

[0002]

2. Description of the Related Art In the formation of a foundation pile, a down-the-hole hammer is generally used when excavating hard ground having a lot of rock or rock. This down-the-hole hammer moves the piston built in the hammer rod up and down by air, hits the excavation bit at the tip of the hammer rod when the piston moves down, and breaks the ground while crushing the rock etc. with this impact force and rotational force. It excavates, and a hammer rod is interlocked and connected by a rotary drive device such as an auger machine.

[0003] When constructing a foundation pile by a drilling device using the down-the-hole hammer, a leader is installed by a crawler crane, an auger machine is mounted on the leader so as to be able to move up and down, and a down-the-hole hammer is vertically connected to the auger machine. The hammer has an air swivel at the upper end. Then, while rotating the down-the-hole hammer by driving the auger machine, excavating the ground and excavating to a predetermined depth, pulling up the down-the-hole hammer through the auger machine, and setting up a pile of H-section steel or the like in the borehole. Then, a grout supply hose is inserted into the borehole to the bottom, and grout such as cement milk for consolidation is injected into the borehole through the hose.

[0004]

In the above-mentioned conventional excavator for forming a foundation pile, since the down-the-hole hammer is rotated by an auger machine supported by the leader, the leader is always required. For this reason, the apparatus becomes large-scale, and it is very difficult to carry in and carry out the reader and to move the reader on site. In addition, in the conventional drilling equipment, in many cases, the grout supply means is not provided on the auger machine side.In order to inject the grout into the drilled hole after the drilling, the down-the-hole hammer is pulled up after the completion of the drilling. Grouting by a grout supply hose was performed manually in addition to the lifting work, which resulted in very poor construction efficiency.

[0005] In view of the above problems, the present invention enables simple excavation of hard ground by using a relatively small crane such as a column-mounted truck or a backhoe-type crane truck, and grout injection. It is an object of the present invention to provide an excavator that can perform an operation automatically without manual operation and without lifting a down-the-hole hammer as in the related art.

[0006]

The invention according to claim 1 is
A rotary drive device 1 supported by a support such as a crane boom so as to be able to ascend and descend, and supported by the support to receive a rotational reaction force; an air introduction path 7 and a grout introduction path 8; A rotary shaft body 2 connected to a rotary drive shaft 6 of the device 1;
A rotary casing which is integrally connected to the lower portion of the rotary shaft 2 so as to be rotatable in a rotatable manner, and in which an air supply path and a grout supply path connected to the air introduction path 7 and the grout introduction path 8 are arranged side by side over the entire length. 3, a down-the-hole hammer 4, which is provided at a lower part in the rotary casing 3 so as to be integrally rotatable and is driven by air supplied from an air supply path;
One swivel mechanism 5 that is externally fitted to the rotating shaft 2 and supplies air and grout to the air introduction path 7 and the grout introduction path 8 of the rotating shaft 2 .

In use of the excavator, the rotary drive 1 is lowered while the rotary drive 1 is supported by a support such as a crane boom M, and the rotary drive 1 is operated to rotate the rotary casing. The ground is excavated by the rotating action of the rotary casing 3 and the striking action of the down-the-hole hammer 4 while rotating 3 and operating the down-the-hole hammer 4. In this case, the rotation driving device 1 does not rotate itself because the rotation reaction force is received by the support. The air for operating the down-the-hole hammer 4 is introduced into the air introduction path 7 of the rotary shaft 2 via the swivel mechanism 5, and from the air introduction path 7, passes through the air supply pipes 22 and 23 in the rotary casing 3, and passes through the down-the-hole hammer 4. It is supplied to the hammer 4.

After excavating to a predetermined depth, the supply of air is stopped and the operation of the down-the-hole hammer 4 is stopped, and grout such as cement milk is swirled by a swivel mechanism 5.
Through the grout introduction passage 8 of the rotary shaft 2 through the grout introduction passage 8 and through the grout supply pipes 27 and 35 in the rotary casing 3 into the drilling hole. Then, after the rotary casing 3 is pulled out of the excavation hole, a pile of H-shaped steel or the like is erected in the excavation hole into which the grout has been injected to form a foundation pile.

Therefore, according to this excavator, if the rotary drive 1 can be mounted so as to be able to move up and down and to receive the rotational reaction force, excavation can be performed without a leader. It becomes possible. In addition, when grout such as cement milk is injected into the drilled hole which has been excavated to the required depth, the rotary casing 3 is not pulled up to the ground, but from the grout introduction passage 8 in the rotary shaft 2 to the rotary casing 3. The grout can be injected directly into the borehole through the grout supply pipes 27,35.

According to a second aspect of the present invention, in the excavator according to the first aspect, the air supply path includes air supply pipes 22 and 30 disposed along the center axis of the rotary casing 3, and the grout supply path is provided. Is composed of grout supply pipes 27 and 35 arranged along the inner wall of the rotary casing 3.

The invention according to claim 3 is the invention according to claim 1 or 2
, The rotary shaft 2 and the rotary casing 3 are detachably connected to each other.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically shows an entire excavator according to the present invention. In this figure, reference numeral 1 denotes a rotary drive attached to a tip of a boom M of a backhoe type crane truck K. The device can be moved up and down by the expansion and contraction swing of the boom M. Reference numeral 2 denotes a rotary shaft body that is interlocked and connected to a rotary drive shaft 6 of the rotary drive device 1. Reference numeral 3 denotes a rotary casing that is vertically connected to a lower portion of the rotary shaft body 2. The down-the-hole hammer 5 provided so as to be integrally rotatable is a swivel mechanism for air and grout (see FIG. 2). The rotation drive device 1 includes a hydraulic motor or an electric motor.

As shown in FIG. 2, an air introduction path 7 and a grout introduction path 8 are provided in the rotary shaft 2 side by side. The upper ends of the air introduction path 7 and the grout introduction path 8 are:
Each of the opening ends 7a, 8a is opened to the side wall of the rotary shaft body 2, and these opening ends 7a, 8a are connected to the air introduction pipes 9, 10 via a swivel mechanism 5, respectively. The lower end of the air introduction passage 7 opens to the side of the fitting hole 11 having a hexagonal cross section formed at the lower end of the rotary shaft 2, and a bent connection pipe 12 is connected to the lower end of the grout introduction passage 8. Have been. An air hose 9a extended to an air compressor (not shown) is connected to the air introduction pipe 9, and a grout hose 10a extended to a grout pressure feed pump (not shown) is connected to the grout introduction pipe 10. Is connected.

The swivel mechanism 5 has a cylindrical body 14 which is rotatable relative to the rotary shaft 2 via a bearing 13 and a required sealing member and is fitted outside so as not to be vertically movable. An annular passage 15 communicating with the upper end opening 7a of the air introduction passage 7 and an annular passage 16 communicating with the upper end opening 8a of the grout introduction passage 8 are formed on the inner peripheral surface of the one of the two annular passages. Air introduction pipe 9 for introducing air into 15
However, grout introduction pipes 10 for introducing grout into the other annular passage 16 are respectively attached to the cylindrical bodies 14.

As shown in FIG. 2, at the upper end of the rotary shaft 2, for example, a prismatic connecting shaft 17 is integrally formed so as to protrude upward. It is adapted to be fitted into a square hole 18 formed in the shaft 6. Thus, as shown in FIG.
The rotary drive shaft 6 and the rotary shaft body 2 of the rotary drive device 1 are integrated with each other by, for example, inserting a bolt 19 through the two in a state fitted into the square hole 18 of the rotary drive shaft 6 and fastening with a nut 20. It is rotatably connected. This rotation drive device 1
As shown in FIG. 1, the boom M is pivotally connected to a tip end of the boom M by a pivot 21, and the boom M receives a rotational reaction force. As shown in FIG. 2, the swivel mechanism 5 includes, for example, a cylindrical body associated with the rotation of the rotating shaft body 2 by a wire S (stopper) connecting the base 1 a of the rotary driving device 1 and the air introduction pipe 9. 14 is prevented from rotating.

As shown in FIGS. 2 and 3, the rotary casing 3 is composed of a plurality of cylindrical casings which are detachably connected to each other, for example, upper and lower two-stage casings 3a, 3a.
b. An air supply pipe 22 as an air supply path is inserted into the upper casing 3a along its central axis, and the upper end of the air supply pipe 22 is connected to the casing 3a.
The lower end of the air supply pipe 22 is fixed to the lower end of the casing 3a via the mounting member 25. The hollow connecting shaft portion 26 is connected to a fitting hole 26a having a hexagonal cross section. A grout supply pipe 27 as a grout supply path is inserted into the upper casing 3a at a position close to the inner surface thereof, and upper and lower ends of the grout supply pipe 27 are connected to the mounting members 23 and 25, respectively. Have been.

The connecting shaft 24 of the upper casing 3a is
The rotary shaft body 2 is fitted into the fitting hole 11 and is detachably connected by a pair of fixing pins 28 which can be inserted and removed, so that the air supply pipe 22 and the air introduction passage 7 in the rotary shaft body 2 are connected to each other. Are communicatively connected. Further, the lower end of the bent connection pipe 12 connected to the grout introduction path 8 in the rotary shaft 2 is connected to the grout supply pipe 27 so as to be detachable from the grout supply pipe 27 at the mounting member 23 of the upper casing 3a. The grout introduction path 8 of the rotating shaft 2 and the grout supply pipe 27 of the upper casing 3a are in communication with each other.

The lower casing 3b is exactly the same as the upper casing 3a, and an air supply pipe 30 is inserted along the center axis of the casing 3b as shown in FIG. Is the casing 3b
The lower end of the air supply pipe 30 is fixed to the lower end side of the casing 3b via an attachment member 33, and is connected to a hollow connection shaft portion 32 having a hexagonal cross section fixed to the upper end via an attachment member 31. The hollow connecting shaft portion 34 is connected to a fitting hole portion 34 a having a hexagonal cross section. Also, this casing 3
A grout supply pipe 35 is inserted along the inner side surface of the casing 3b, and an upper end of the grout supply pipe 35 is connected to the mounting member 31, and a lower end of the grout supply pipe 35 is provided in the window 3 provided in the casing 3b.
6 and open to the outside, a check valve 37 is provided in the opening. The check valve 37 is composed of, for example, a pair of semicircular rubber plates, and both rubber plates are opened outward against the elasticity when grout is supplied.

As shown in FIG. 3, the upper connection shaft portion 32 of the lower casing 3b is fitted into the fitting hole 26a of the lower connection shaft portion 26 of the upper casing 3a, so that it can be inserted and removed. The pair of fixing pins 38 are detachably connected to each other, whereby the air supply pipes 22 and 30 (air supply paths) in the upper and lower casings 3a and 3b are connected to each other and the grout supply pipes 27 and 35 (grout). Are connected to each other.

A hexagonal connecting shaft portion 40 of a hollow hammer connecting rod 39 is fitted into a fitting hole 34a of the lower connecting shaft portion 34 of the lower casing 3b. The hammer connecting rod 3 is detachably connected by a pair of fixing pins 41 which can be inserted and removed.
A tapered screw portion 43 formed at the upper end of the down-the-hole hammer 4 is screwed and connected to a tapered screw hole 42 formed at the lower end of the hole 9. This down the hole hammer 4
Although it is well known, it is not shown in the figure. However, a cylinder is provided inside the hammer body 4a, and a hammer piston sliding in the cylinder reciprocates by supplying compressed air. Strikes the excavation bit 44 protruding from the lower part of the hammer body 4a. Air is supplied from the upper end of the hammer 4 through the hollow portion of the hammer connecting rod 39 from the lower casing 3b as shown in FIG. The down-the-hole hammer 4 is a rotary casing 3
And rotates with the rotation of the rotary casing 3. In addition, on the outer peripheral surface of each of the casings 3a and 3b, narrow strip-shaped protruding ridges 45 are provided along the entire length of the casing at fixed intervals (for example, intervals of 60 degrees) in the circumferential direction. I have.

In order to excavate the ground and create a foundation pile using the excavator having the above-described configuration, first, the boom M of the crane K is operated to extend and swing from the state shown in FIG. While lowering the rotary drive device 1, the rotary drive device 1 is operated to rotate the rotary casing 3 and the down-the-hole hammer 4 is operated to strike the excavation bit 47 while rotating the rotary casing 3. The ground is excavated by the impact of the down-the-hole hammer 4. The air for operating the down-the-hole hammer 4 is introduced from the air introduction pipe 9 to the air introduction path 7 of the rotary shaft 2 via the swivel mechanism 5, and the air from the air introduction path 7 is supplied to the air supply inside the rotary casing 3. It is supplied to the down-the-hole hammer 4 through the pipes 22 and 23.

After excavating to a predetermined depth, the supply of air is stopped and the operation of the down-the-hole hammer 4 is stopped, and then the grout pressure pump on the ground is started to feed grout such as cement milk into the grout hose 10a and the grout hose 10a. The grout is introduced from the grout introduction pipe 10 into the grout introduction passage 8 of the rotary shaft 2 via the swivel mechanism 5.
Through the bent connecting pipe 12 to the grout supply pipe 27 in the upper casing 3a, and further to the grout supply pipe 35 in the lower casing 3b, and inject into the drilling hole from the tip.

While the grout is injected into the borehole as described above, the rotary drive unit 1 is raised by the raising operation of the boom M, and the rotary casing 3 is rotated by operating the rotary drive unit 1. The rotary casing 3 is pulled up via the rotary shaft 2. By the time the rotary casing 3 has been pulled up to the ground, the required amount of grout has been filled in the borehole. After the rotary casing 3 is lifted from the drill hole, a reinforcing pile such as an H-beam or the like and other required piles are erected in the drill hole filled with grout to form a foundation pile.

As described above, according to the excavator of the present invention, the rotary drive unit 1 is mounted on the boom M of the backhoe crane K so as to be able to move up and down, and is connected to the rotary drive shaft 6 of the rotary drive unit 1. Rotating shaft body 2 to be rotated, and a rotating casing 2 suspended from the lower portion of the rotating shaft body 2.
A down-the-hole hammer 4 integrally rotatably provided in a lower portion of the rotary casing;
And a swivel mechanism 5 for supplying air and grout to the grout introduction path 8, such that the rotary casing 2 is rotated via the rotary shaft 2 by the rotary drive device 6 attached to the boom M of the crane K. As a result, excavation can be performed without a leader, so that the operation is very simple and easy, and the excavation can be performed to a necessary and sufficient depth. Moreover, the supply of air to the down-the-hole hammer 4 can be performed from the air introduction path 7 of the rotary shaft 2 through the air supply pipes 22 and 30 (air supply path) in the rotary casing 3.

In addition, when grouting cement milk or the like into a drilling hole having been excavated to a required depth, the rotary casing 3 is rotated while pulling out the rotary casing 3 without lifting the rotary casing 3 to the ground. Since grout can be directly injected from the grout introduction path 8 in the shaft body 2 through the grout supply pipes 27 and 35 in the rotary casing 3, the grout injection work can be started immediately after the end of the drilling hole. . That is, in the conventional excavator, after excavation to a predetermined depth is completed, the rotary casing is pulled up, and a grout supply hose connected to the grout pump is manually inserted into the excavation hole to the bottom thereof, thereby injecting grout. According to the excavator according to the present invention, the work of inserting the grout supply hose into the borehole and the work of lifting the hose are not required at all, and the grout injection work is facilitated. It can be performed quickly.

The air supply path is composed of air supply pipes 22 and 30 laid along the central axis of the rotary casing 3, and the grout supply path is a grout supply pipe 27 laid along the inner wall of the rotary casing 3. , 35, the arrangement of the air supply path and the grout supply path in the rotary casing 3 is simple and easy, and the connection of the air supply path to the down-the-hole hammer 4 is also facilitated. Also,
Since the rotating shaft 2 and the rotating casing 3 are detachably connected to each other, the handling of the rotating shaft 2 and the rotating casing 3 and the loading and unloading thereof are facilitated, and the air introduction path 7, the grout introduction path 8, The cleaning operation of the air supply pipes 22 and 30 and the grout supply pipes 27 and 35 becomes easy.

In this embodiment, as shown in FIG.
Grout supply pipe 35 disposed in lower casing 3b
Is opened through the casing 3b so that grout is discharged to the outside of the casing 3b. However, the tip of the grout supply pipe 35 extends from the middle of the casing 3b in this way. It is also possible that the grout from the grout supply pipe 35 is injected downward into the borehole through the gap between the down-the-hole hammer 4 and the casing 3b without opening the casing 3b downward without opening it outside. Good. In addition, the description has been given of the rotating casing 3 including the upper and lower casings 3a and 3b. However, the rotating casing can be constituted by three or more casings. Therefore, the required number of casings depends on the length of the ground hole. The casings may be used by being added to each other.

[0028]

According to the first aspect of the present invention, there is provided a rotary driving device supported by a support such as a crane boom so as to be able to move up and down and to receive a rotational reaction force on the support, A rotary shaft body connected to a rotary drive shaft of the drive device, a rotary casing hanging and connected to a lower portion of the rotary shaft body, a down-the-hole hammer provided integrally rotatable at a lower portion in the rotary casing, and a rotary shaft body. A swivel mechanism for supplying air and grout to the air introduction path and the grout introduction path is provided, and the rotary casing is rotated via a rotary shaft by a rotary drive device attached to a crane boom or the like. It is possible to perform excavation even without the above, so that the operation becomes very simple and easy, and it is possible to excavate to a necessary and sufficient depth. Moreover, the supply of air to the down-the-hole hammer can be reliably performed from the air introduction path of the rotary shaft through the air supply path in the rotary casing.

Further, when grout is injected into the excavated hole after excavation, grout is injected into the excavation hole through the grout supply pipe in the rotary casing from the grout introduction passage in the rotary shaft without lifting the rotary casing to the ground. Therefore, the grouting operation can be started immediately after the completion of the excavation. Therefore, unlike the conventional excavator, there is no need to insert the grout supply hose into the borehole and pull up the hose, and grout injection work can be performed easily and quickly. Can be improved.

According to the second aspect of the present invention, the air supply path comprises an air supply pipe disposed along the central axis of the rotary casing, and the grout supply path is disposed along the inner wall of the rotary casing. Because of the grout supply pipe, the air supply path into the rotary casing and the piping of the grout supply path are simple and easy, and the connection of the air supply path to the down-the-hole hammer is facilitated.

According to the third aspect of the present invention, the rotary shaft and the rotary casing are detachably connected to each other, so that the rotary shaft and the rotary casing can be easily handled and loaded and unloaded. The introduction path, the grout introduction path, the air supply pipe, and the grout supply pipe can be easily cleaned.

[Brief description of the drawings]

FIG. 1 is a side view showing an entire excavator according to the present invention.

FIG. 2 is an enlarged detailed cross-sectional view showing an upper end portion of a rotary casing in the excavator of FIG.

FIG. 3 is an enlarged detailed sectional view showing an intermediate portion and a lower end portion of the rotary casing in the excavator of FIG. 1;

[Explanation of symbols]

 K crane M boom 1 rotary drive 2 rotary shaft 3 rotary casing 4 down-the-hole hammer 5 swivel mechanism 6 rotary drive shaft of rotary drive 7 air introduction path 8 grout introduction path 9 air introduction pipe 10 grout introduction pipe 22 air supply pipe 27 Grout supply line 30 Air supply line 35 Grout supply line 44 Down the hole hammer drill bit

Claims (3)

(57) [Claims] A rotary drive device supported by a support such as a crane boom so as to be able to ascend and descend and receiving a rotational reaction force by the support; an air introduction path and a grout introduction path; A rotary shaft body connected to a rotary drive shaft of the rotary drive device, an air supply path connected to the lower portion of the rotary shaft body so as to be rotatable integrally with the lower part thereof, and internally connected to the air introduction path and the grout introduction path; A rotary casing having grout supply paths arranged side by side over the entire length, a down-the-hole hammer provided integrally rotatably at a lower portion in the rotary casing and driven by air supplied from an air supply path, and externally fitted to a rotary shaft body It is equipped, and one scan <br/> Iberu mechanism for supplying air and grout into the air introduction path and grout introduction path of the rotating shaft body, excavating apparatus comprising a. 2. The air supply path comprises an air supply pipe disposed along a central axis of the rotary casing, and the grout supply path comprises a grout supply pipe disposed along an inner wall of the rotary casing. A drilling rig according to claim 1. 3. The excavator according to claim 1, wherein the rotating shaft and the rotating casing are detachably connected to each other.