JP3004267B1 - Drilling rig - Google Patents

Abstract

An object of the present invention is to facilitate foundation work by enabling a clamshell inserted into a casing tube to cut and remove obstacles such as rock and large boulders. SOLUTION: An excavator 1 is inserted into a casing tube 71 which is pressed into the ground by an all-casing excavator 70. The excavator body 20 includes a gripper 25 that can be locked to the casing tube 71, a pair of clam shells 50, a hydraulic cylinder 52 that opens and closes the clam shell 50, and the clam shell 50 around the axis of the casing tube 71. And a sand pump for discharging muddy water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a drilling rig,
More specifically, the present invention relates to a technique for facilitating removal of soil from a casing tube and removal of obstacles in a so-called all casing method.

[0002]

2. Description of the Related Art One of the cast-in-place pile methods developed in recent years is an all-casing method. FIG. 8 is a schematic explanatory view of the all casing method. In the figure, a casing tube 92 is pressed into the ground by a hydraulic press-fitting device 91 installed on the ground, and the sediment inside is, for example, a hydraulic telescopic boom 9.
It is grasped using a clamshell (also called a clamshell bucket) 94 at the three ends. In the case of the oscillating type, since the casing tube 92 itself has no cutting ability, the tip may hit an obstacle such as a large boulder and may not be propelled. When the obstacle cannot be grasped by the clamshell 94, the obstacle can be crushed to a certain extent by free-falling a hammer club (not shown). However, if the obstacle is rock or reinforced concrete, it is removed. It is difficult to press-fit the casing tube 92. It should be noted that there is an environmental problem due to noise in the hammer club. Therefore,
An all-rotation all-casing excavator in which a casing tube is provided with a cutting ability has been developed. In this technology, a casing tube is rotated by a hydraulic motor and pushed into the ground by a hydraulic cylinder so that a bit at the tip of the casing tube can cut a ground or an obstacle.

[0003]

However, when the above-mentioned conventional full-rotation all-casing excavator is used,
The longer the casing tube, the greater the power loss due to friction with the ground. For this reason, measures to reduce friction are used, but it is still difficult to cut rock and large boulders, and there is a problem in that a large amount of power is required. Once the press-fitting is insufficient, the construction period and cost are adversely affected.

The present invention has been made in view of the above circumstances, and an object of the present invention is to cut and remove obstacles such as large boulders by a so-called all casing method using a drilling (discharge) device inserted into a casing tube. To make the foundation work easier.

[0005]

For this purpose, the following excavator was created. A first aspect of the present invention is an excavator having the configuration described in claim 1. In addition, when the casing tube is pressed into the ground, the ground is a part of the ground that is cut into the inside of the casing tube,
It is a general term for soil, sand, stone, etc., but here, it also includes obstacles such as the ground, bedrock, and large boulders immediately below the casing tube. In this excavator, earth and sand near the lower end of the casing tube pressed into the ground is excavated (discharged) by scooping or grabbing with a clam shell driven by an opening / closing drive mechanism. In addition, the ground can be cut by rotating the clam shell by the rotation drive mechanism. That is, the bottom surface of the excavation can be easily excavated almost flat, so that the casing tube can be easily press-fitted. By rotating the clamshell in a sufficiently widened state, the clamshell can be dug directly under the casing tube with the tip of the clamshell. If the casing tube hits an obstacle such as a bedrock or a large boulder, which makes it more difficult to press-fit the obstacle, after cutting the obstacle with a clamshell, debris is grasped by the clamshell.

In the conventional all-rotation all-casing excavator, the power loss due to the friction between the outer peripheral surface of the casing tube and the ground is large. Therefore, the longer the casing tube is, the more the cutting ability is significantly reduced. On the other hand, the excavator according to the present invention can exhibit a predetermined cutting ability regardless of the length (depth) of the casing tube. That is, a relatively small excavator can cope with the construction of a cast-in-place pile at a large depth, and the clamshell only needs to perform a cutting operation when necessary in accordance with the underground situation. This excavator may be used in combination with a full-rotation all-casing excavator, and the efficiency of excavation work is further enhanced.

[0007] A second aspect of the present invention has a configuration according to a second aspect. In addition, the front here means the direction of press-fitting the casing tube, that is, the direction of digging. In this excavator, after the excavator main body is locked (fixed) at a predetermined depth position (usually near the lower end) in a casing tube, the extruder is pushed out in a press-in direction by a feed mechanism while rotating the clam shell. To cut ground and obstacles. The reaction force at that time can be received on the casing tube side via the locking mechanism. Therefore, there is no generation of noise or vibration as in the case where a conventional hammer grave is freely dropped and excavated. Further, unlike the earth drill, there is no need to insert a power transmission mechanism such as a long shaft from above the casing tube, so that the apparatus is simplified. The work efficiency is good because the debris of the ground and obstacles that have been cut can be grasped by the clamshell.

[0008] A third invention has a configuration according to a third aspect. In this excavator, three construction methods, i.e., removal of muddy water and mud by a sand pump, excavation and earth removal by a clamshell, and cutting by rotating the clamshell, can be selected, and the construction can be proceeded by appropriately using them in combination. In addition, it is possible to switch to a construction method suitable for the underground situation on the spot, so that it is possible to dig efficiently. In other words, it is possible to change the construction method without re-installing the excavating machine, and the number of man-hours and costs for changing the construction method can be minimized. The sand pump is preferably provided with a cutter on a rotating shaft protruding from the pump body so as to pulverize (or disturb) earth and sand.

A fourth aspect of the present invention has the configuration according to the fourth aspect. That is, by attaching a cutting bit to the clamshell, cutting efficiency is improved, and wear of the clamshell is prevented.

[0010]

Next, an embodiment of the present invention will be described with reference to the drawings. 1 is a front sectional view of the drilling rig, FIG. 2 is a side sectional view of the drilling rig, and FIG. 3 is a III-II of FIG.
FIG. 4 is a top view of the excavator, and FIG. 5 is a bottom view of the excavator. The excavator 1 is used by inserting it into a casing tube that is pressed into the ground in a so-called all-casing method, and the movable frame 30 moves up and down on a cylindrical excavator body 20 formed to have a diameter slightly smaller than the casing tube. Mounted as possible, movable frame 3
A rotating body 40 supported by a hollow support shaft 31 which is a support portion fixed to 0 is driven to rotate around the axis of the casing tube, and a clam shell 50 is mounted on the tip of the rotating body 40 so as to be capable of opening and closing. It is a schematic configuration. FIG.
Shows a state in which the clamshell 50 is closed by imaginary lines. Hereinafter, description will be made in order.

The main body 20 of the excavator has an appearance in which both ends of a cylinder are tapered, and a hanging ear 22 is attached to an upper surface of an upper support portion 21. A gripper device 23 as a mechanism is provided. This gripper device 23 excavates by using a cylinder device 24 such as a hydraulic cylinder to protrude a gripper 25, which is a locking member, radially from four equally-divided positions on the outer periphery of the excavator main body and strongly press the inner wall of the casing tube. The apparatus main body 20 is formed so that it can be fixed substantially concentrically with the casing tube and at a predetermined depth position.

A guide portion 26 is provided on the inner wall of the body 20 of the excavator so as to extend in the vertical direction (ie, in the direction of the cylindrical axis). The wheels 32 of the movable frame 30 roll along the rails of the guide portion 26. I can do it. The hydraulic cylinder device 2 suspended from the upper support 21
The rod end 28a of 8 is connected to the movable frame 30, and the movable frame 30 moves up and down by the action of the cylinder device 28. At this time, the hollow support shaft 31 is guided by the cylindrical portion of the upper support portion 21 and slides up and down. The above-described cylinder device 28 constitutes a feed mechanism according to the present invention. In FIG. 1, the movable frame 30 is shown in a lowered position, and in FIG. 2, it is shown in an raised position.

The rotating body 40 is formed in a substantially cylindrical shape, and a large gear 41 is fixed to the upper end. Then, the rotating body 40 is fitted to the bearing
3 and rotatably supported by the movable frame 30 via thrust bearings 42 disposed on both upper and lower sides of the large gear 41. The large gear 41 meshes with a small gear 35 at the shaft end of a hydraulic motor 34 attached to the movable frame 30, and the rotary body 40 is driven to rotate by the hydraulic motor 34. The gear drive and the hydraulic motor 34 constitute a rotation drive mechanism according to the present invention. Note that a configuration in which the rotary drive mechanism is driven by an electric motor or an engine is also possible.

An end member 43 is fixed to the lower end of the rotating body 40. A pair of clam shells 50 are attached to the end member 43.
Are rotatably mounted around a mounting shaft 45 extending perpendicular to the axis of the rotating body 40. Note that a thrust bearing 44 is interposed between the end member 43 and the hollow support shaft 31.

The rod end of the hydraulic cylinder 52 is pin-connected to the mounting pin 51 of the back support of the clamshell 50, and the base end of the hydraulic cylinder 52 is rotatable on the flange-shaped mounting part 46 of the rotating body 40. Supported. That is,
The pair of clam shells 50 is a cylinder device constituting the opening / closing drive mechanism referred to in the present invention, specifically, a hydraulic cylinder 5.
Opening and closing operations are formed by the operations of 2, 52. A plurality of cutting bits 53 and 54 are fixed to the clam shell 50 at the toe for scooping earth and sand, and at the lower end edge in the open state and the mating surface in the closed state.

Further, an electric underwater sand pump 60 is attached to the hollow support shaft 31. The sand pump 60 is provided with a rotating shaft having a cutter 61 at its tip, and the sand 61 can be disturbed by the cutter 61 slightly projecting downward from the position of the end member 43. The tip of a hose 62 for discharging muddy water extending from the sand pump 60 is guided to a settling tank (not shown) installed outside the casing tube. A power cable (not shown) from the ground is connected to the motor of the underwater sand pump 60.

The hydraulic devices (cylinder devices 24, 28, hydraulic motor 34, hydraulic cylinder 52) are supplied with oil from a hydraulic device installed on the ground, although illustration of piping and the like is omitted. ing. Note that the cylinder device can be changed to an electric actuator, a motor-driven link mechanism, or the like.

Next, the operation of the drilling rig 1 having the above configuration will be described. FIG. 7 is a schematic explanatory view of a cast-in-place pile method using an all-casing excavator. First, an all-casing excavator (standing pile construction machine) 70 installed on the ground
This vertically presses the casing tube 71 into the ground. In this case, the all casing excavator 70 may be a swing type or a full-rotation type. Then, the swing and rotation of the casing tube 71 are stopped, and the excavator 1 suspended on the suspension wires 73 of the crane 72 is inserted into the casing tube 71. The cylinder device 24 of the gripper device 23 is operated near the lower end of the casing tube 71 to push out the gripper 25 in the radial direction, and to press the inner wall of the casing tube 71, whereby the excavator body 20 is pressed.
Is locked (fixed) at a predetermined depth position.

This excavator 1 can be roughly used in the following three ways. (1) Excavation and Discharge When the hydraulic cylinder 52 is operated while the excavator 1 is locked on the casing tube 71, the clam shell 50 whose rear side is pressed down rotates around the mounting shaft 45.
By opening and closing the clamshell 50, earth and sand are scooped or excavated so as to be grasped. Thereafter, the excavator 1 unlocked to the casing tube 71 is lifted by the crane 72 and discharged. This is the original use of clamshell. The cross-sectional shape of the bottom of the excavation hole (ground) is generally as shown in FIG. Depending on the properties of the earth and sand, the excavator 1
The clamshell 50 may be opened and closed while being suspended without being locked to the casing tube 71, and the excavator 1 may be used to excavate using its own weight.

(2) Cutting and Discharge When the hydraulic motor 34 is operated while the excavator 1 is locked on the casing tube 71, torque is transmitted via a gear device to rotate the rotating body 40 and the clamshell 50. Rotates together. With the pair of clamshells 50 substantially open from each other, the ground is cut with the bits 53 and 54. At that time, if necessary, the cylinder device 28 is operated to extrude the movable frame 30, the hollow support shaft 31, and the rotating body 40 integrally, and the clam shell 50 is sent downward. The cut earth and sand is picked up by the clam shell 50 that has stopped rotating, or is discharged together with muddy water by a sand pump 60 described below. As a result, the excavated bottom surface is moved to the position shown in FIG.
As shown in (1), the excavation can be performed almost flat, so that the casing tube 71 can be easily press-fitted.

In the same manner as described above, the clamshell 50 can also cut off obstacles such as rock and large boulders to an appropriate size and then grab debris. Even if the bedrock could be hollowed out only with the casing tube 71 of the all-casing method, it would be difficult to carry it out of the casing tube 71 as it is, so that the clamshell 50 was used to cut the rock as shown in this example. It can be seen that the work efficiency of the discharge method is high.

When the cutting ability of the cutting edge of the casing tube 71 is insufficient, the cutting by the casing tube 71 is temporarily stopped, and instead, the clamshell 50 is rotated in a sufficiently opened state so that the portion immediately below the casing tube 71 is rotated. A usage method of excavating in advance is also possible. Thus, the drilling rig itself has cutting means,
A predetermined cutting ability can be exhibited regardless of the length (depth) of the casing tube 71.

(3) Drainage of muddy The sand pump 60 is operated to discharge muddy water to a sedimentation tank (not shown) on the ground, where sediment is separated and the wrinkle water is returned to the excavation hole. The circulation system of the circulating water includes a pump suction system and an air lift system. When the sand pump 60 is operated, it is preferable to use both rotation and feeding of the clamshell 50. That is, while cutting the ground with the rotating clamshell 50, the cutter 61 at the tip of the pump disturbs the muddy water to pulverize a large lump. This enables efficient soil removal.

As described above, this single excavator can be used for various purposes such as discharging muddy water by a sand pump, rubbing earth and sand with a clamshell, grabbing rocks and the like with a clamshell, and cutting rock and the like with a clamshell. It can respond to various construction methods.

[0025]

According to the drilling device of the present invention, when constructing a standing pile by the all-casing method, it is possible to relatively easily cut and remove obstacles such as rock and large boulders using a clam shell. In addition, it can be excavated with a clamshell or can be discharged with a sand pump. As described above, since the construction method can be appropriately selected according to the situation, there is an effect that the foundation work can be promptly performed.

[Brief description of the drawings]

FIG. 1 is a front sectional view of an excavator.

FIG. 2 is a side sectional view of the excavator.

FIG. 3 is a sectional view taken along line III-III of FIG. 2;

FIG. 4 is a top view of the excavator.

FIG. 5 is a bottom view of the excavator.

FIG. 6 is a diagram illustrating an excavated cross section.

FIG. 7 is a diagram illustrating a use mode of the excavator.

FIG. 8 is a diagram illustrating a conventional excavator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drilling apparatus 20 Drilling apparatus main body 23 Gripper apparatus 25 Gripper 28 Cylinder apparatus 30 Movable frame 40 Rotating body 50 Clamshell 52 Hydraulic cylinder 60 Sand pump 71 Casing tube

Claims (4)

(57) [Claims] An excavator used by being inserted into a casing tube pressed into the ground, wherein the excavator main body has a pair of clamshells and an opening / closing operation for opening and closing the clamshell to dig the ground. An excavator comprising: a drive mechanism; and a rotary drive mechanism that causes the clamshell to perform a rotary operation for cutting ground. 2. The excavator main body includes: a locking mechanism for locking the excavator main body at a predetermined depth position of a casing tube; and a feed mechanism for pushing out the clamshell driven by rotation. The drilling rig according to claim 1. 3. The excavator according to claim 2, wherein the excavator main body includes a sand pump for discharging muddy water. 4. The excavator according to claim 1, wherein a bit for cutting is attached to the pair of clamshells.