JPH094350A - Ground improvement boring machine - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a ground improvement boring machine that can give high torque to a boring rod and can perform endless step pull-out without stopping rotation of the boring rod in the ground improvement process. provide. [Structure] Drill head 4 into which a boring rod is fitted
The fitting hole 22 of the spindle 14 is formed in a cross-sectional shape capable of transmitting torque to the boring rod, the rod holder 6 and the chuck 30 for holding the boring rod fitted to the spindle 26. Be equipped with.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground improvement boring machine. More specifically, the present invention relates to a boring machine used to improve the ground by excavating the ground to a predetermined depth and then injecting the improving material into the ground through a boring rod.

[0002]

2. Description of the Related Art Conventionally, as this type of ground improvement boring machine, a drill head is movably provided on a leader,
It is known that the drill head gives a boring rod a rotational force and a feeding force to excavate the ground, and injects the improvement material into the ground while performing step extraction of the boring rod at a predetermined stroke. Specifically, the boring rod is fitted to the spindle of the drill head, and is gripped by the chuck provided on the spindle so that the torque and the advancing force for rotation are transmitted.

In such a boring machine, when the torque is increased in order to improve the excavation efficiency, the drill head becomes large. Further, since the torque is transmitted through the chuck, this chuck also needs to have a strong gripping force.

In the ground improvement process in which step extraction is performed subsequent to excavation, the drill head is rapidly advanced to move to the next step extraction step after retreating a stroke of 3.5 m, for example. At that time, since the chuck of the drill head is opened, the rotation of the boring rod is stopped. That is, the ground improvement work is interrupted.

[0005]

SUMMARY OF THE INVENTION The present invention has been made on the basis of the above technical background, and has the following objects.

The object of the present invention is to prevent the drill head from increasing in size and the chucking capacity to increase.
An object of the present invention is to provide a ground improvement boring machine capable of giving a high torque to a boring rod and improving excavation efficiency.

Another object of the present invention is to improve the ground so that the endless step extraction can be performed without stopping the rotation of the boring rod in the ground improvement process in which the step extraction process is repeated and the improvement efficiency can be improved. The purpose is to provide a boring machine.

[0008]

The present invention employs the following means in order to achieve the above object.

That is, the present invention relates to a boring machine for ground improvement, which is provided in a leader so as to be movable along its longitudinal direction, and includes a drill head for giving a rotating force and a feeding force to a boring rod. Has a housing and a fitting hole that is rotatably supported in the housing and into which the boring rod is fitted,
A spindle having the fitting hole formed in a cross-sectional shape capable of transmitting torque to the boring rod, a driving means for rotationally driving the spindle, and a peripheral wall of the spindle are provided to grip the boring rod. It is a boring machine for ground improvement that is equipped with a chuck for.

Further, according to the present invention, a drill head is provided movably along the longitudinal direction of the leader for giving a rotating force and a feeding force to a boring rod, and the drill head is provided in the vicinity of the front end of the leader. In a ground improvement boring machine including a rod holder for holding a rod, the drill head is rotatably supported in a housing and the housing, and the drill head is rotatably in the housing into which the boring rod is fitted. A spindle having a fitting hole into which the boring rod is fitted, the fitting hole having a cross-sectional shape capable of transmitting torque to the boring rod, and a spindle for rotationally driving the spindle. A driving means and a chuck provided on the peripheral wall of the spindle for holding the boring rod are provided. A rod holder, a spindle rotatably supported in the housing and having a fitting hole into which the boring rod is fitted; and a spindle provided on a peripheral wall of the spindle for gripping the boring rod. It is a boring machine for ground improvement that is equipped with a chuck.

Further, the present invention is the boring machine for ground improvement, wherein the fitting hole of the spindle of the drill head has a square cross section.

[0012]

According to the present invention, the spindle of the drill head has a fitting hole having a sectional shape capable of transmitting torque to the boring rod, for example, a rectangular sectional shape. Therefore, a Kerry rod having the same cross-sectional shape is used as the boring rod fitted to this spindle. By fitting the Kelly rod and the spindle, high torque can be transmitted without depending on the gripping force of the chuck. The chuck may have a function of transmitting the feeding force to the boring rod.

Further, according to the present invention, the rod holder is provided with a spindle having a chuck. In the ground improvement process, the chuck of the drill head is opened at the time of transition from one step drawing process to the next step drawing process, and the drill head is fast forwarded. At this time, the chuck of the rod holder is closed,
The boring rod is held, but the boring rod is rotatable with respect to the rod holder via the spindle. Therefore, it is possible to advance and fast-forward the drill head without stopping the rotation of the boring rod and shift to the next step withdrawal stroke. That is, the endless step can be pulled out.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing the whole ground improvement boring machine of the present invention, and FIG. 2 is a side view. The swivel vehicle 1 is equipped with a reader including a main reader 2 and a sub reader 3.

The main leader 2 is provided with a drill head 4 for giving a rotating force and a feeding force to the boring rod so as to be movable along the longitudinal direction of the leader. The drill head 4 moves on the reader 2 by driving the feeding device. This feeding device comprises a hydraulic motor 5 provided on the swivel carriage 1, a sprocket (not shown), a chain, etc., and is well known in the art. The feeding device is provided with a stroke detection device (not shown) such as a rotary encoder and a limit switch for detecting a stroke when the step is pulled out.

A rod holder 6 for holding a boring rod is fixed to the swivel carriage 1 near the lower end of the main leader 2, and the rod holder 6 is used for the drill head 4.
And the axis are aligned. The winch 7 is for winding a wire rope, which suspends an excavating tool such as a boring rod, through a head sheave 8. 2 is an input power box 10
Shows the control boards respectively.

FIG. 3 is a sectional view of the drill head 4. The drill head 4 has a base plate 11 attached to the main reader 2, and a housing including a first housing 12a and a second housing 12b is fixed to the base plate 11. First housing 12a and second
The housings 12b are connected to each other by a hydraulic cylinder 40. The spindle 14 is the first housing 12a
It is housed in the second housing 12b and is rotatably supported via a plurality of bearings 15. A spindle gear 16 is provided on the outer circumference of the spindle 14 in the first housing 12a. Second housing 1
In 2b, the outer circumference of the spindle 14 and the bearing 1
A sleeve 41 is interposed between the sleeve 41 and the sleeve 5.

The spindle 14 is attached to the first housing 12a.
A hydraulic motor 17, which is a driving means for rotationally driving, is fixed. A drive shaft 18 of the hydraulic motor 17 projects into the first housing 12a, and a drive gear 19 is fixed to the drive shaft 18. An idle shaft 20 is provided between the spindle gear 16 and the drive gear 19. The idle gear 2 rotatably provided on the idle shaft 20.
1 meshes with the drive gear 19 and the spindle gear 16, respectively. With such a structure, the hydraulic motor 1
7 is transmitted to the spindle 14 and the spindle 14
Rotates.

The spindle 14 has a fitting hole 22 into which a boring rod is fitted, and the fitting hole 22 has a rectangular cross section. The cross-sectional shape of the fitting hole 22 is not limited to a quadrangle, and may be another polygon. In the second housing 12b, a plurality of (four in this embodiment) chucks 23 are provided on the peripheral wall of the spindle 14. The chuck piece 24 of the chuck 23 includes a hydraulic cylinder 40.
With the movement of the second housing 12b and the sleeve 41 in the axial direction by the operation of, the closed position (solid line position in FIG. 3) protruding from the inner peripheral surface of the spindle 14 to grip the boring rod and the peripheral wall of the spindle 14 are drawn. Move to and from the open position (the position indicated by the chain line in FIG. 3) where the boring rod is ungrip.

FIG. 4 is a sectional view of the rod holder 6, and FIG. 5 is a bottom view thereof. Like the drill head 4, the rod holder 6 also has a housing including a first housing 25a and a second housing 25b connected to each other by a hydraulic cylinder 42. A spindle 26 is rotatably supported by the first housing 25a and the second housing 25b via a plurality of bearings 27. Second
In the housing 25b, a sleeve 43 is interposed between the outer periphery of the spindle 26 and the bearing 27.

The spindle 26 has a fitting hole 28 into which the boring rod is inserted, and the lower hole 29 of the fitting hole 28 has a rectangular cross-section having the same shape as the fitting hole 22 of the spindle 14 of the drill head 4. There is. In the second housing 25b, a plurality of chucks 30 are provided on the peripheral wall of the lower hole 29 of the spindle 26. The chuck 30 has the same structure as the chuck 23 of the drill head 4 described above, and is opened and closed by the operation of the hydraulic cylinder 42. The annular laminated plate 38 provided on the spindle 26 is
It is a member for removing the mud attached to the boring rod.

FIG. 6 is a sectional view in the axial direction of a boring rod applied to the boring machine of the present invention, FIG. 7 is a sectional view showing its connected state, and FIG. 8 is a sectional view taken along the line AA of FIG. The bowling rod 31 has a square cross section (quadrangle in this embodiment, see FIG. 8), that is, a kelly rod. Supply path 32 inside the boring rod 31
Drilling water or ground improvement material is supplied through.

A male coupling 33 is formed at the tip of the boring rod 31, and a female coupling 34 is formed at the rear end thereof. As shown in FIG. 7, the boring rod 31 is connected by fitting a male coupling 33 to a female coupling 34. The male coupling 33 and the female coupling 34 have a joint pin 35 at the time of connection.
A pin groove 36 and a pin hole 37 for inserting the pin are formed respectively.

Ground Improvement Method FIG. 9 is an explanatory view of the ground improvement method using the boring machine. The boring rod 31 is fitted to the spindles 14 and 26 of the drill head 4 and the rod holder 6, respectively.
The chucks 23 and 30 are closed and opened,
Excavation is started by giving a turning force and a feeding force to the boring rod 31 (FIG. 9A).

At this time, since the boring rod 31 is fitted to the spindle 14 with a rectangular cross section, high torque can be transmitted. Therefore, the chuck 23
Has only to have a function of transmitting the feeding force to the boring rod 31, and is small and lightweight. Since the boring rod 31 is also fitted to the spindle 26 of the rod holder 6, the rod holder 6 is mounted on the boring rod 31.
It functions as a guide and reduces the deflection of the rod.

When the excavation reaches a predetermined depth, the excavation is stopped (FIG. 9 (b)). Then, the step of pulling out the boring rod 31 is started, and the injection of the improving material is started (FIG. 9C). The chuck state at this time is that the chuck 23 of the drill head 4 is closed and the chuck 30 of the rod holder 6 is open, as in the case of excavation. The step pull-out is performed by repeating the raising and lowering (forward and backward) of the drill head 4 with a predetermined stroke (for example, 20 to 30 mm) (Fig. 9 (d)).

When the boring rod 31 is gripped and changed at the lowered position of the drill head 4, one step withdrawal process is shifted to the next step withdrawal process. When the drill head 4 descends, the chuck 23 is opened, the chuck 30 of the rod holder 6 is closed, and the boring rod 31 is held by the rod holder 6. This time,
The boring rod 31 is the spindle 2 of the rod holder 6.
Since it is rotatable with respect to the rod holder 6 via 6, it is possible to perform a series of operations from the lowering of the drill head 4 to the re-grasping of the drill head 4 while continuing the rotation of the boring rod 31. That is, the endless injection is performed without interruption of the improvement material injection. Each chuck 2
Table 1 shows the relationship between the opening and closing of Nos. 3 and 30 and the rotation of the boring rod 31.

[0028]

[Table 1] The ground improvement by the above-mentioned step pulling out is performed within a predetermined depth range, and the injection work is finished (FIG. 9E).

[0029]

As described above, according to the present invention, it is possible to apply a high torque to the boring rod without increasing the size of the drill head and without increasing the chucking capacity, thereby improving the drilling efficiency. be able to. Also,
In the ground improvement process in which the step extraction process is repeated, endless step extraction can be performed without stopping the rotation of the boring rod, and the improvement efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a front view showing the entire ground improvement boring machine of the present invention.

FIG. 2 is a side view of the boring machine.

FIG. 3 is a sectional view of a drill head.

FIG. 4 is a sectional view of a rod holder.

FIG. 5 is a bottom view of the rod holder.

FIG. 6 is an axial sectional view of a boring rod applied to the boring machine of the present invention.

FIG. 7 is a cross-sectional view showing a connected state of a boring rod.

8 is a cross-sectional view taken along the line AA of FIG.

FIG. 9 is an explanatory diagram of a ground improvement method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Revolving carriage 2, 3 ... Reader 4 ... Drill head 12a, 12b ... Housing 14 ... Spindle 17 ... Hydraulic motor 22 ... Fitting hole 23 ... Chuck 25a, 25b ... Housing 26 ... Spindle 28 ... Fitting hole 30 ... Chuck 31 … Bowling rod

Claims (3)

[Claims] 1. A ground improvement boring machine, comprising a drill head movably provided along a longitudinal direction of the leader and for applying a rotating force and a feeding force to a boring rod, wherein the drill head is a housing. A spindle having a fitting hole rotatably supported in the housing, into which the boring rod is fitted, the fitting hole having a cross-sectional shape capable of transmitting torque to the boring rod; A boring machine for ground improvement, comprising: a driving unit for rotationally driving a spindle; and a chuck provided on a peripheral wall of the spindle for holding the boring rod. 2. A drill head movably provided along the longitudinal direction of the leader for giving a rotating force and a feeding force to the boring rod, and a drill head provided near the front end of the leader for holding the boring rod. In a ground improvement boring machine including a rod holder for carrying out, a drill head is rotatably supported in a housing and the housing, and is rotatably supported in the housing into which the boring rod is fitted. A spindle having a fitting hole into which the boring rod is fitted, the fitting hole having a cross-sectional shape capable of transmitting torque to the boring rod, and a driving means for rotationally driving the spindle. A chuck for gripping the boring rod, the chuck being provided on a peripheral wall of the spindle. A holder, a housing, a spindle rotatably supported in the housing, and a spindle having a fitting hole into which the boring rod is fitted, and a chuck provided on a peripheral wall of the spindle for holding the boring rod. A ground improvement boring machine equipped with. 3. The ground improvement boring machine according to claim 1, wherein the fitting hole of the spindle of the drill head has a rectangular cross section.