JPH05141167A - Shaft sinking machine - Google Patents

Abstract

PURPOSE:To provide a shaft sinking machine capable of obtaining sufficient directional corrective force in addition to be capable of performing earth cutting in a manner, while it is only enough to set the extent of strength in a drill pipe to that taking account of earth removal and drill bit rotation, leading to a reduction in cost. CONSTITUTION:Operating a rotational driver 3, a drill pipe 2 and a ground cutting drill bit 1 are rotated, while a thrust is given to this drill bit 1 by each steering jack 10, thus earth cutting takes place. At this time, a relative displacement between the ground and the earth cutting drill bit 1 is detected by two displacement detectors 11 and 12, transmitting a displacement detecting signal to be secured at that time to a thrust controller of the steering jacket 10. With the control signal secured here, the thrust of each steering jack 10 is controlled, and further the thrust of the drill bit 1 and the drilling direction are controlled as well.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft excavator.

[0002]

2. Description of the Related Art A conventional shaft excavator will be described with reference to FIG. 5, in which 01 is a ground excavating drill bit, 02 is a drill pipe that can be added, and 015 is a guide pipe attached to the lower end of the drill pipe 02. 01 is attached to the lower end of the guide pipe 015.

Reference numeral 03 is a kerry bar connected to the upper end of the drill pipe 02, 04 is a swivel joint attached to the upper end of the kelly bar 03, 05 is a crane suspension for suspending and supporting the swivel joint 04, and 011 is Base frame installed on the ground, 07 is the same base frame 011
A gate-type mast installed above, 08 is a support stand supported by the gate-type mast 07 so as to be able to move up and down, 010 is an elevating jack for raising and lowering the support stand 08, and 09 is a rotary drive for rotating the kerry bar 03. In this device, the rotary drive device 09 is installed on the support frame 08.

[0006] Reference numeral 06 denotes an elevating rod that can be added vertically to the supporting base 08, 012 is supported by the elevating rod 06, and a gripper device slidably inserted in the guide pipe 015, and 013 is the supporting device. Stand 08
The laser transmitter mounted on the upper part and the laser receiver 014 mounted on the gripper device 012. In the vertical shaft excavator shown in FIG. 5, the rotary drive unit 09 is activated to rotate the drill pipe 02, the guide pipe 015 and the ground excavating drill bit 01 to excavate the ground.

At this time, the lifting jack 010 is operated,
Lower the lifting rod 06 and the gripper device 012,
While holding the gripper device 012 at a position directly above the ground excavating drill bit 01, the gripper device 012 is operated in the extension direction to bring the tip end of the gripper device 012 into contact with the side surface of the vertical shaft to guide the guide pipe 015 and the ground excavation. The drill bit 01 for use is rotatably supported.

At this time, the laser transmitter 013 and the laser receiver 014 detect the relative displacement between the ground and the drill bit 01, and the displacement detection signal obtained at that time is detected by the stroke control device (not shown) of the gripper device 012. To the gripper device 01 by the control signal obtained here.
The stroke of No. 2 is controlled to correct the direction of the drill bit 01.

[0007]

In the conventional shaft excavator shown in FIG. 5, the formation is inclined, there is a discontinuity in the formation, and the reaction force of the gripper device 012 is sufficient depending on the state of the formation. If it cannot be removed, excavation becomes unstable and sufficient direction correction force cannot be obtained. Further, in order to transmit the reaction force of the excavation, it is necessary to increase the strength of the drill pipe 02, which causes a problem of high cost.

The present invention has been proposed in view of the above problems, and its object is to enable stable excavation and obtain sufficient direction correction force.
Further, the strength of the drill pipe may be set in consideration of the soil removal and the rotation of the drill bit, and it is another object of the present invention to provide a shaft excavator which can reduce the cost.

[0009]

In order to achieve the above object, a shaft excavator according to the present invention comprises a drill pipe which is rotatably supported by a rotary drive installed on the ground, and a drill pipe which can be replenished. In a vertical shaft excavator having a ground excavating drill bit attached to the lower end of the, a plurality of steering jacks that perform the propulsion and direction correction of the drill bit, and a displacement detector that detects the relative displacement of the drill bit with respect to the ground, A thrust control device for calculating the thrust of each of the steering jacks based on the displacement detection signal from the displacement detector and controlling the thrust of the steering jacks by the control signal obtained as a result.

[0010]

The shaft excavator of the present invention is constructed as described above, and the rotary driving device is operated to rotate the drill pipe and the ground excavating drill bit, while the steering jacks allow the ground excavating drill bit to operate. Give thrust to and excavate. At this time, the displacement detector detects the relative displacement between the ground and the drill bit for ground excavation, and the displacement detection signal obtained at that time is sent to the thrust control device of each steering jack, and by the control signal obtained here, The thrust of each steering jack is controlled to control the thrust of the drill bit for ground excavation and the excavation direction.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The shaft excavator of the present invention will now be described with reference to an embodiment shown in FIGS. 1 and 2. 1 is a drill bit for ground excavation, 2 is a hollow Kelly type drill pipe that can be added,
4 is a swivel / joint attached to the upper end of the drill pipe 2, 5 is a crane hanging device for suspending and supporting the swivel / joint 4, 6 is a portal mast installed on the ground, 1
6 is a support stand provided on the gate type mast 6 and 3 is a rotary table (rotary drive device) installed on the support stand 16.
Then, the rotary table 3 is adapted to rotate the drill pipe 2.

Reference numeral 7 denotes a plurality of suspension jacks installed on the ground, and each suspension jack 7 fixedly supports the segment 9. 10 is a plurality of steering jacks attached to the lower end of each segment 9 through pins (not shown),
The lower ends of the respective steering jacks 10 are attached to the drill bit 1 via a swivel ring (thrust bearing) 13, and the drill bit 1 is rotatably supported.

Reference numeral 11 is a laser receiver mounted on the drill bit 1 through a swivel ring (thrust bearing) 17, 12 is a laser transmitter mounted on the portal mast 6, and 8 is a laser transmitter for these laser receivers 11 and 11. A rod that can be added to the container 12 and has a function of preventing reflection or attenuation of the laser. Reference numeral 14 is a ground compressor, and 15 is an air pipe connecting the compressor 14 and the swivel joint 4 described above. The compressed air generated in the compressor 14 is sent to the air pipe 15 → swivel joint 4 → outside, and drilled by the drill bit 1. The earth and sand are sucked into the drill pipe 2 to the swivel joint 4 and discharged outside together with the compressed air.

Next, the operation of the shaft excavator shown in FIGS. 1 and 2 will be specifically described. The rotary table 3 is operated to rotate the Kelly type drill pipe 2 and the ground excavating drill bit 1. On the other hand, each segment 9 fixedly supported by each suspension jack 7 and each steering jack 10
By applying a thrust to the drill bit 1 for ground excavation,
Excavate.

At this time, the relative displacement between the ground and the ground excavating drill bit 1 is detected by the laser transmitter 12 and the laser receiver 11, and the displacement detection signal obtained at that time is detected by the thrust control device of each steering jack 10. (Not shown), the thrust of each steering jack 10 is controlled by the control signal obtained here to control the thrust of the ground excavating drill bit 1 and the excavating direction.

The above operation will be described more specifically with reference to FIG. In order to build a caisson vertically in the ground, control of the excavation direction of the shaft excavator is essential. Therefore, the laser transmitter 12 and the laser receiver 11 detect the relative displacement between the ground and the drill bit 1 for ground excavation, and the displacement detection signal obtained at that time is used as a thrust control device (a personal computer or a personal computer). Programmable controller, etc.), the same control device determines the difference from the target value, determines whether it is within the allowable range, and calculates the control amount when the range is exceeded.

The control signal obtained as a result is sent to a control valve of a power unit (for example, a hydraulic power source) of each steering jack 10, and the control valve is operated to adjust the set pressure of each steering jack 10. For example, in FIG.
When the current excavation direction is shifted to the right side of FIG. 2, the thrust F ₁ of the steering jack 10 on the right side is increased,
The thrust F ₂ of the left steering jack 10 is set to a small value and the direction is corrected to the left (see the white arrow).

FIG. 3 is a block diagram showing a basic correction flow at the time of automatic direction control, and FIG. 4 is an explanatory diagram showing a work flow. The laser transmitter 12 and the laser receiver 1 described above
1 may be changed to another detector, for example, an inclinometer.

[0019]

As described above, the shaft excavator of the present invention operates the rotary drive device to rotate the drill pipe and the ground excavating drill bit, and at the same time, each steering jack applies thrust to the ground excavating drill bit. Give and excavate. At this time, the displacement detector detects the relative displacement between the ground and the drill bit for ground excavation, and the displacement detection signal obtained at that time is sent to the thrust control device of each steering jack, and by the control signal obtained here, By controlling the thrust of each steering jack, to control the thrust of the drill bit for ground excavation and the excavation direction, by contacting the gripper device to the side surface of the shaft like the conventional shaft excavator,
Since it is not necessary to rotatably support the guide pipe and the ground excavating drill bit, the excavation can be performed stably, and a sufficient direction correction force can be obtained.

Further, the strength of the drill pipe may be set in consideration of the soil removal and the rotation of the drill bit, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of a shaft excavator of the present invention.

FIG. 2 is an operation explanatory view of the vertical shaft excavator.

FIG. 3 is a block diagram showing a basic correction flow during automatic direction control of the vertical shaft excavator.

FIG. 4 is an explanatory diagram showing a work flow of the vertical shaft excavator.

FIG. 5 is a vertical sectional side view showing a conventional shaft excavator.

[Explanation of symbols]

 1 Drill bit for ground excavation 2 Drill pipe 3 Rotation drive device 10 Steering jack 11 Displacement detector 12 〃

Claims (1)

[Claims] 1. A vertical shaft excavator having a drill pipe rotatably supported by a rotary drive installed on the ground, which is rotatably supported, and a ground drill drill bit attached to a lower end portion of the drill pipe. Multiple steering jacks for propulsion and direction correction,
A displacement detector for detecting the relative displacement of the drill bit with respect to the ground, and the thrust of each steering jack is calculated by the displacement detection signal from the displacement detector, and the thrust of the steering jack is calculated by the control signal obtained as a result. A shaft excavator characterized by having a thrust control device for controlling.