JP3236451B2 - Excavation stirrer channel switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow path switching device used in an excavating and stirring device of an excavating machine applied to a soil improvement method for improving a ground by injecting a solidified material while excavating and stirring the ground. Things.

[0002]

2. Description of the Related Art For example, a so-called deep mixing treatment method is known as one of soil improvement methods for soft ground or the like.
In this deep mixing method, a ground improvement section in which a solidified material is agitated and mixed is formed below an improvement unnecessary section. In this method, the solidified material is injected into the ground near saturation, causing volume expansion in the ground, causing ground deformation in the horizontal direction, and possibly affecting surrounding underground structures. There is a problem.

[0003] In order to solve such problems,
The present applicant has already developed and applied for a ground improvement method and device capable of reliably preventing ground deformation despite injecting a solidified material in the deep mixing method (Japanese Patent Publication No. 5-62167). Gazette).

In this apparatus, as shown in FIG. 7, a drilling / stirring head 101 is provided at a lower part of a drilling rod 100, and a screw blade 102 is provided at an upper part thereof. Has a lower discharge port 104
From the double pipe in the drilling rod to the upper discharge port 10
3 and the lower discharge port 104 can be independently supplied with a solidified material C such as a cement material.

At the time of construction, the upper unneeded section and the lower ground improvement section are excavated, and when the ground improvement section is excavated to a predetermined depth, the remaining lower end is excavated while discharging the solidified material from the lower discharge port 104. -The lower end of the ground improvement section is improved by stirring, and then the upper discharge port 103 is formed so that the injected solidified material is well stirred and mixed with the soil.
The excavating rod 100 is pulled up while discharging the solidified material C from above, and the solidified material is agitated and mixed while discharging the soil upward by the screw blade 102, thereby preventing the volume expansion of the ground improvement section.

Conventionally, a drilling and stirring device for a ground improvement machine that performs such a construction method is provided with a double pipe swivel 105 at the upper end of a drilling rod 100, and two hoses 106 and 107 are connected to the double pipe swivel 105. The solidified material C can be supplied to the inner pipe 108 communicating with the upper discharge port 103 and the outer pipe 109 communicating with the lower discharge port 104, respectively.

[0007] The two hoses 106 and 107 are connected to a flow path switching device 112 connected to a pump 111 of the mixing plant 110 to switch the hoses.

[0008]

However, the above-mentioned conventional excavating and stirring apparatus for a ground improvement machine has the following problems.

(1) Two hoses are required for one drilling rod, and a specially constructed double pipe swivel is required, which increases the cost.

(2) Since two hoses are connected to one drilling rod, the number of hoses in a two- to five-shaft multi-shaft excavator becomes extremely large, and the weight of the hoses increases. Workability is greatly reduced.

(3) When the distance from the mixing plant to the excavator is long, the cost of the hose increases because two hoses are used for one drilling rod. This is especially true for multi-screw excavators.

(4) As the number of hoses increases and the length of hoses increases, maintenance costs due to breakage and the like also increase.

(5) Since the excavating rod on which the auger motor is mounted has a double-pipe structure as a whole, a dedicated double-pipe auger motor is required in place of the versatile single-axis auger motor, and the cost is reduced. Get higher.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object thereof is to selectively supply a fluid such as a solidified material to an upper discharge port and a lower discharge port at the tip of a drilling rod. At the same time, a single-axis swivel can be used,
Only one hose is required for one drilling rod, and a versatile single-axis auger motor can be used.
It is still another object of the present invention to provide a flow path switching device of a drilling and stirring device capable of easily and reliably switching a flow path in a rotating drilling rod.

[0015]

SUMMARY OF THE INVENTION A flow switching device according to the present invention.
As shown in FIG. 1, the excavating and stirring device having a device supplies a fluid such as a solidified material through a swivel 25 into a excavating rod 3 that is rotationally driven by an auger motor 4, and transfers the fluid to the tip of the excavating rod 3. As shown in FIGS. 1 and 2, in the excavating and stirring device which selectively discharges from the first discharge port 11 </ b> A and the second discharge port 11 </ b> B provided in the portion, the swivel 25 inserts the auger motor 4 into the drill rod 3. The common supply holes 30 and 33 are provided to a flow path switching position below the first flow path, and the first supply passages 36A and 32A and the second supply passage 36B are respectively provided from the flow path switching position to the first discharge port 11A and the second discharge port 11B. , 32B, and the common supply holes 30, 33 are provided in the first supply passage 3 at the flow path switching position.
There is provided a flow path switching device for selectively communicating with 6A, 32A and the second supply passages 36B, 32B.

As shown in FIGS. 1, 2 and 5, the flow path switching device according to the present invention is provided below the auger motor 4 of the excavating rod 3 rotated by the auger motor 4, and is commonly provided at the upper portion. A flow path switching rod 20 in which a supply hole 33 is formed and a first supply path 36A and a second supply path 36B are respectively formed in a lower part;
And a first outlet passage 41A and a second outlet side which are connected to the common supply hole 33 and communicate with the first supply passage 36A and the second supply passage 36B, respectively. The channel 41B, the first outlet channel 41A and the second
A flow path switching valve 22 having a valve body 43 supported to close the outlet side flow path 41B and an operation spool 46 for operating the valve body 43, and is fixedly disposed on the side of the flow path switching rod 20. Switching actuators 2 such as air cylinders
3 and a switching operation mechanism 24 that transmits the driving force of the switching actuator 23 to the operating spool 46 of the rotating flow path switching valve 22 to operate the valve body 43.

The switching actuator 23 is attached to the flow switching rod 20 and moves up and down together with the excavating rod 3, and is slidable on the reader 2 and the like so as not to rotate with respect to the rotating flow switching rod 20. Attach to When the excavating rod 3 is a two-axis ground improvement machine, the holding member 52 holding the rotating excavating rod 3 is attached to the fixing connecting member 50 having both ends, and the holding body 52 is attached to the excavating rod 3.
And lock it vertically.

The switching mechanism 24 includes an operating disk 57 which is vertically moved by the switching actuator 23,
A cam follower 59 is connected to the operation spool 46 and holds the operation disk 57 from above and below.

[0019]

In the above-described configuration, the solidification material C is supplied to one drilling rod 3 from a mixing plant via one hose, and one common supply hole 30, It flows into the flow path switching valve 22 through 33.
In the flow path switching valve 22, the switching actuator 2
3, the valve body 43 is switched by the switching operation mechanism 24, the common supply holes 30, 33 communicate with the first supply passages 36A, 32A or the second supply passages 36B, 32B, and the solidified material C is supplied to the first discharge port 11A or the first discharge passage 11A. It is selectively discharged from the two discharge ports 11B.

Therefore, a general single-axis rod can be used for the upper portion of the drilling rod 3, a single-axis swivel can be used, and one hose can be used for one drilling rod 3. Further, a general-purpose single-axis auger motor can be used as the auger motor 4.

The flow path in the rotating excavating rod 3 is controlled by the flow path switching valve 22 having a valve element 43 operated by an operation spool 46 and the switching operation mechanism 24 including an operation disk 57 and a cam follower 59. Switching can be performed easily and reliably in the middle of the rod.

[0022]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention. This is an example in which the present invention is applied to a two-axis ground improvement machine used in the deep mixing processing method. FIG. 1 shows the entirety of the two-axis ground improvement machine, and FIGS. 2 and 3 show partially enlarged views of the excavation rod. .

In FIG. 1, the two-axis ground improvement machine mainly includes a crawler crane main body 1, a leader 2, and a drill rod 3.
And a rotary drive device 5 having a built-in auger motor 4 and a gear transmission mechanism, and the like. The rotary drive device 5 guided and supported by the reader 2 is lifted and lowered by a suspension wire rope 6 so that the excavation rod 3 rotates. It goes down and goes up and down.

The excavating rod 3 has an excavating / stirring head 7 at the tip and a screw rod having a screw blade 8 at an intermediate part. The excavating / stirring head 7 includes an excavating wing (auger) 9, an agitating blade 10, an anti-corotating wing (not shown) provided as necessary, and a lower discharge port 11 </ b> A at a lower part and an upper discharge port 11 </ b> B at an upper part. Is provided.

The outer diameter of the screw blade 8 depends on the stirring blade 1
The diameter is smaller than 0 and is set so that the soil can be discharged by an amount corresponding to the solidified material to be injected. Further, the two excavating rods 3 are steadyed by the lower steadying member 12, and
The excavating / stirring head 7 is rotatably connected by a connecting member 13.

In such a ground improvement machine, in the present invention, a flow path switching rod 20 is interposed above the excavating rod 3 and the flow path switching rod 20 is connected to the connecting rod 21.
To the shaft coupling of the rotary drive 5. The switching rod 20 for switching the flow path, the switching actuator 23, and a switching operation mechanism 24 that can operate the rotating flow path switching valve 22 are provided on the flow switching rod 20.
Is provided.

Then, as shown in FIG. 2, one common supply hole 30 is formed in the center of the connecting rod 21. On the other hand, inside the excavation rod (screw rod) 3, a double pipe composed of an inner pipe 31A and an outer pipe 31B is provided.
, A first supply passage 32A communicating with the lower discharge port 11A and a second supply passage 3 communicating with the upper discharge port 11B.
Form 2B.

Therefore, as shown in FIG.
As the swivel connected to the upper end of the swivel, a general-purpose swivel 25 having a single flow path can be used, and only one hose 26 needs to be provided for one drilling rod 3. Also,
The auger motor 4 can also be a general-purpose single-axis auger motor.

As shown in FIG. 2, the flow path switching rod 20
In the upper part of the common supply hole 33 continuous with the common supply hole 30
Drilling. A first supply passage 36A continuous with the first supply passage 32A and a second supply passage 36B continuous with the second supply passage 32B are formed below the passage switching rod 20 by the center hole 34 and the internal pipe 35. I do. The drill rod 3
Flange joints 37 and 38 are attached to the upper end of the connecting rod 21 and the lower end of the connecting rod 21, respectively, and the rods 3 and 21 are respectively connected to the upper and lower ends of the flow switching rod 20 by flange joining.

A passage switching valve 22 for selecting the first supply passage 36A and the second supply passage 36B is fixed to the intermediate portion of the passage switching rod 20 via a bolt. As shown in FIGS. 5 and 6, the flow path switching valve 22 is a kind of three-way valve, and has one inlet flow path 40 and two first outlet flow paths 4.
It comprises a 1A / second outlet flow path 41B, a valve chamber 42, a ball valve element 43, an operating piece (leaf spring) 44, two valve seats 45A and 45B, an operating spool 46, and the like.

The inlet side channel 40 is connected to the common port 3 through the inlet port.
3 and the outlet port is opened to the valve chamber 42. The outlet ports of the first outlet channel 41A and the second outlet channel 41B communicate with the first supply passage 36A and the second supply passage 36B, respectively, and each inlet port is opened to the valve chamber 42. Valve seats 45 are provided at the inlet ports of the outlet flow paths 41A and 41B.
A, 45B are provided.

The ball valve element 43 is supported by an operating piece 44 so that the valve seats 45A and 45B can be closed by swinging up and down in the valve chamber 42. One end of the operating piece 44 is pivotally supported by a shaft 47, and the ball valve body 43 is rotatably mounted on the other end thereof via a mounting member 48 composed of a U-shaped member and a pin. The operation spool 46 is connected to the operation piece 4 via the connection piece 49.
4 to the middle part.

With the above configuration, when the operation spool 46 moves up and down by the switching operation mechanism 24 described later, the operation piece 44 tilts up or down. Ball valve element 4
When the valve 3 closes the valve seat 45B, the inlet flow path 40 communicates with the first outlet flow path 41A. When the valve seat 45A is closed, the inlet flow path 40 communicates with the second outlet flow path 41B.

The switching actuator 23 is an air cylinder or a hydraulic cylinder. As shown in FIGS.
It is arranged between two flow path switching rods 20 so that the flow path switching valves 22 on both sides can be simultaneously switched. The switching actuator 23 attaches the cylinder base to the upper fixing connecting member 50 and moves the lower movable connecting member 51 up and down.

As shown in FIGS. 2 and 4, the fixing connecting member 50 has holding members 52 at both ends, and holds the upper portion of the flow path switching rod 20 with the holding members 52. This holding body 52
Are vertically locked by a pair of locking projections 53 provided on the flow path switching rod 20. Therefore, both ends of the fixing connecting member 50 are supported and fixed to the rotating flow path switching rod 20. The cylinder base of the switching actuator 23 is pinned to the center of the fixing connecting member 50 via the bracket 54.

The movable connecting member 51 is, as shown in FIG.
The front end of the piston rod is pinned to the center portion via a bracket 55, and slide holders 56 are attached to both ends. The slide holder 56 has a horizontal plate-shaped operating disk 5
7 are provided integrally, and the operation spool 46 of the flow path switching valve 22 is provided.
Can be driven up and down. Since the flow path switching valve 22 rotates together with the excavating rod 3, as shown in FIG. 5, an operating member 58 is protruded downward at a lower portion of the operating spool 46, and the operating disk 57 is vertically attached to the operating member 58. A pair of cam followers 59 to be clamped from above are rotatably mounted.

Even if the flow path switching valve 22 rotates together with the excavating rod 3, the cam follower 59 rolls on the upper and lower surfaces of the operating disk 57, and the vertical driving of the operating disk 57 is smoothly performed by the operating member 58 and the operating spool 46. And the ball valve element 43 can be moved up and down. The flow switching rod 20
Is provided with a stopper 60 for limiting the lower limit position of the slide holder 56 (see FIG. 2).

In the above-described configuration, for example, in the case of the deep mixing treatment method, the following operation is performed.

(1) The excavating rod 3 is lowered while being rotated to excavate an upper unnecessary section, and further excavated to a predetermined depth at a lower portion of the ground improvement section, that is, leaving a lower end portion of the ground improvement section by a predetermined range. I do.

(2) The lower end of the ground improvement section is improved.
The flow path switching valve 22 switches the state shown in FIG.
The solidified material C from 3 is discharged from the lower discharge port 11A through the first supply passages 36A and 32A. In this state, the excavating rod 3 is rotated while the solidified material C is discharged from the lower discharge port 11A, and the excavating rod 3 is lowered to the lowermost position to perform excavation and stirring.

(3) With the excavating rod 3 rotating,
When the slide holder 56 is raised by the switching actuator 24, the ball valve 43 is raised by the operating disk 57 and the cam follower 59, and the state shown in FIG. 2 is reached, and the solidified material C passes through the second supply passages 36B and 32B. Outlet 1
1B. In this state, the excavating rod 3 is lifted while the solidified material C is discharged from the upper discharge port 11B, and is lifted and stirred. At this time, the soil corresponding to the amount of the solidified material injected is carried upward by the screw blade 8 and discharged to the ground, thereby preventing the volume expansion of the ground improvement section due to the injected solidified material.

(4) When the injection, agitation, and lifting of the ground improvement section are completed, the injection of the solidified material from the upper discharge port 11B is stopped, the drilling rod 3 is pulled up while rotating, and the construction is completed.

Although the above description has been given of the deep-layer mixing method, the present invention is not limited to this, and the present invention can be applied to other ground improvement methods, for example, when the excavating rod is excavated or pulled up while repeating the descending and the ascending while injecting and stirring. It is needless to say that can be applied.

Further, the present invention can be applied not only to the ground improvement method but also to the case where it is necessary to discharge a solidified material or the like from two discharge ports in the ground strengthening / reinforcement method.

[0045]

As described above, the present invention has the following configuration, and thus has the following effects.

(1) Since only one common supply hole is required from the swivel to the flow path switching position, a general-purpose swivel can be used, and one hose is required for one drilling rod.
Significant reduction in cost, significant improvement in workability, etc. can be achieved.
In particular, in the case of a two- to five-shaft multi-shaft excavator, the number of hoses and the entire length of the hose can be significantly reduced, and the cost, workability, maintenance cost, and the like are remarkable.

(2) Similarly, a general-purpose auger motor for a single axis can be used, and the cost can be reduced.

(3) Since the flow path switching valve is operated by the switching operation mechanism including the operating disk, the cam follower, and the like, the switching of the flow path rotating together with the excavation rod can be performed easily and reliably in the middle of the rod.

[Brief description of the drawings]

FIG. 1 shows the entire ground improvement machine according to the present invention,
(A) is a side view, (b) is a front view.

FIG. 2 is a longitudinal sectional view showing the flow path switching device (at the time of injection / withdrawal stirring by an upper discharge port) in FIG. 1;

FIG. 3 is a longitudinal sectional view showing the flow path switching device (during injection / downward excavation by a lower discharge port) in FIG. 1;

4A is a cross-sectional view taken along line aa of FIG. 3, and FIG.
3 is a sectional view taken along line bb of FIG. 3, and FIG. 3C is a sectional view taken along line cc of FIG.

FIG. 5 is an enlarged sectional view of the flow path switching device.

FIG. 6 is a sectional view taken along line VI-VI of FIG. 5;

FIG. 7 is a schematic view showing a conventional ground improvement machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Crawler crane main body 2 ... Leader 3 ... Excavation head 4 ... Auger motor 5 ... Rotary drive device 6 ... Suspended wire rope 7 ... Excavation / stirring head 8 ... Screw blade 9 ... Excavation wing (auger) 10 ... Stirring wing 11A ... Lower part Discharge port 11B Upper discharge port 20 Flow switching rod 21 Connection rod 22 Flow switching valve 23 Switching actuator 24 Switching mechanism 25 Swivel 26 Hose 30 Common supply hole 31A Inner pipe 31B outer pipe 32A first supply passage 32B second supply passage 33 common supply hole 34 central hole 35 pipe 36A first supply passage 36B second supply passage 37, 38 flange joint 40 Side flow path 41 First outlet flow path 42 Valve chamber 43 Ball valve element 44 Working piece (leaf spring) 45 Valve seat 46 Working spool 50 Solid Fixed connecting member 51 ... Movable connecting member 52 ... Holding body 53 ... Locking projection 56 ... Slide holding body 57 ... Working disk 58 ... Working member 59 ... Cam follower

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) E02D 3/12 102

Claims (1)

(57) [Claims] 1. A flow path provided below an auger motor of a drilling rod that is rotationally driven by an auger motor, a common supply hole is formed in an upper part, and a first supply path and a second supply path are formed in a lower part, respectively. A switching rod, an inlet-side flow path attached to the center of the flow path switching rod, and communicating with the common supply hole;
A first outlet channel and a second outlet channel respectively communicating with the supply passage, a valve body supported so as to close the first outlet channel and the second outlet channel, A flow path switching valve having an operation spool to be actuated, a switching actuator fixedly arranged on the side of the flow path switching rod, and an operation spool of the flow path switching valve rotating the driving force of the switching actuator. drilling stirring apparatus characterized by transmitting to and a switching actuation mechanism for actuating the valve body
The flow path switching device.