JP7432458B2 - soil improvement machine - Google Patents

Description

The present invention relates to a soil improvement machine, and more particularly, to a soil improvement machine that improves the ground by stirring and mixing excavated earth and sand with an injected soil improvement agent.

In order to improve soft ground in construction and civil engineering work, ground improvement machines are used to harden the ground by injecting and stirring a ground improvement agent such as cement milk into an excavated hole. This type of ground improvement machine has a ground improvement agent injection hose (grout hose) connected to the upper end of a screw shaft, which is a hollow drilling shaft, via a swivel joint, and a drilling head with a digging blade and stirring blade at the lower end. The attached screw shaft, which is rotated, is lowered along the leader to excavate the ground, and the soil improvement agent sent through the screw shaft is ejected from the excavation head to mix earth and sand with the soil improvement agent. Stirring.

Due to the mounting structure of the swivel joint, which is a rotating joint, there is a risk that the body side will rotate due to the resistance of the seal part installed between the coupling (shaft side) and the body (hose side). As a means for preventing the swivel joint from rotating, the soil improvement machine is equipped with a telescoping rod installed upright on a rotary drive device, and a connecting member connecting the telescoping rod and the swivel joint. The connecting member is configured to rotatably hold the coupling of the swivel joint while also holding the connected injection hose, whereby the swivel joint is held non-rotatably in a fixed position on its body side; The rotating screw shaft is designed to prevent co-rotation (for example, see Patent Document 1).

Japanese Patent Application Publication No. 2009-203659

The telescoping rod that constitutes the anti-corroboration means has a telescopic structure in which multiple pipes are fitted in order, and when the pipes are contracted, they are pinned using pin insertion holes that overlap, so that they can fall along the leader. This prevents the product from stretching unexpectedly during transportation. However, although the pin locking structure is simple, the decision of when to attach and detach the lock pin is left to human judgment, and it is difficult to do this in a timely manner at the work site. If the pin is inserted into the pin insertion hole and forgotten to be removed, the telescopic rod will be prevented from moving in the extending direction when the screw shaft is assembled, and there is a risk of damaging various parts of the anti-corrosion means.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a ground improvement machine equipped with a rod stopper member that can appropriately restrict the extension of a telescoping rod without impairing workability.

In order to achieve the above object, the ground improvement machine of the present invention includes a base machine in which an upper rotating body is rotatably provided on the upper part of the lower traveling body, and a leader that is provided in the front part of the upper rotating body so that it can be raised and lowered. , comprising a rotary drive device that moves up and down along the leader, a screw shaft attached to the rotary drive device, and a swivel joint provided at the upper end of the screw shaft to which a soil improvement agent injection hose is connected, In the ground improvement machine in which the rotary drive device is provided with a telescoping rod that is extendable and retractable along the screw shaft, and the telescoping rod and the swivel joint are connected by a connecting member, the leader is in a vertical working position. and a transport position in which the rotary drive device is held at the lower end and is laid down backward, and the upper revolving body has a structure that blocks the moving direction of the telescopic rod according to the up-and-down movement of the leader. The present invention is also characterized in that a rod stopper member is provided that blocks the extension direction of the telescoping rod in the transportation posture.

Further, the rod stopper member has a contact surface that is disposed opposite to the extending direction of the telescoping rod in the transportation attitude, and thereby allows the tip end of the telescoping rod to abut, and the contact surface is It is characterized by being made of an elastic material. Furthermore, the telescoping rod is characterized in that, in the transportation position, the extension direction is held at an angle that is diagonally upward rather than horizontal.

According to the ground improvement machine of the present invention, since the upper revolving body is provided with a rod stopper member that does not block the moving direction of the telescopic rod according to the up-and-down movement of the leader, and that blocks the extending direction of the telescopic rod in the transportation posture, It is possible to quickly and appropriately restrict the extension of the telescopic rod and release the restriction by simply raising and lowering the leader. This not only reliably prevents the telescopic rod from stretching on the trailer bed during transportation, but also reduces the preparation time before starting work and when removing it from the site after work is completed. This contributes to improving the safety and work efficiency of those who handle the improved machine.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a soil improving machine according to an embodiment of the present invention, showing a working posture with a leader standing up; It is a figure which shows an example of the anti-rotation device provided in the ground improvement machine. It is a side view which shows the state of the transportation posture which laid down the leader. It is also a side view of the main part. It is also a rear view of the main part.

1 to 5 are diagrams showing a ground improvement machine of the present invention. As shown in FIGS. 1 and 2, the ground improvement machine 11 is a base machine composed of a lower traveling body 12 equipped with a crawler and an upper revolving body 13 rotatably provided on the lower traveling body 12. 14, a leader 15 erected at the front of the upper revolving body 13, a leader undulation cylinder 16 that supports the leader 15 from the rear, and an auger 17 which is a rotary drive device provided on the leader 15 so as to be movable up and down. It is equipped with Furthermore, a leader support 18 that supports the leader 15 in a movable manner is provided at the front portion of the upper revolving body 13. Further, a driver's cab 19 is provided on the right side of the upper revolving body 13, and an engine storage house 20 for storing equipment such as an engine and a hydraulic pump is provided on the left side. In addition, a counterweight 22 for balancing the ground improving machine 11 is mounted on the rear end of the upper revolving body 13.

The leader 15 is formed by connecting a plurality of leader members each having a rectangular cylindrical cross section, and is rotatably attached to a support shaft 23 provided on the leader support 18 in the vehicle width direction. Further, the upper end of the leader 15 is equipped with a top sheave 24 around which a lifting rope is wound, and the lower front part is equipped with an openable and closable steady stop device 25 that prevents swinging of rotationally driven construction members. A pair of left and right guide pipes 26, 26 are continuously provided at the front end portions of both sides of the leader 15 over the entire length of the leader 15.

The auger 17 includes a chuck mechanism 17b that grips the workpiece that has passed through the gear case 17a, and an auger drive hydraulic motor 17c that applies rotational driving force to the workpiece, and slides into the guide pipes 26, 26. A pair of left and right guide gibs 17d, 17d are provided so as to protrude rearward, and are movable up and down along the front surface of the leader 15 by a chain that is passed through sprockets provided above and below the leader 15.

When performing ground improvement using the ground improvement machine 11, a screw shaft is used as a construction member. The screw shaft 27 is a hollow tube through which a soil improvement agent such as cement milk can be added, and has chucks that engage with the chuck mechanism 17b at multiple locations in the length direction including the upper shaft 28 at the upper end. A square shaft portion 27b with a groove 27a is provided, and an excavation head 29 having an excavation blade 29a and a stirring blade 29b is attached to the lower end. Further, a swivel joint 30 is attached to the upper end of the upper shaft 28, and an injection hose (grout hose) 31 is connected to the swivel joint 30.

In the swivel joint 30, a coupling 30a connected to the upper shaft 28 and a body 30b to which the injection hose 31 is connected are assembled so that they can rotate relative to each other, and even when the screw shaft 27 rotates, the rotational force is applied to the injection hose 31. It is designed not to be transmitted. However, since a leak-preventing seal is interposed between the coupling 30a and the body 30b, there is a risk that the body 30b side will rotate together due to the resistance of the seal portion. Therefore, a rotation prevention device is used to prevent the swivel joint 30 from rotating together.

The detent device 32 includes a telescopic rod 33 that is extendable and retractable along the screw shaft 27 and is provided on the auger 17, and the telescopic rod 33 and the swivel joint 30 are connected by a connecting member 34.

The telescopic rod 33 has a telescopic structure in which three pipes 33a, 33b, and 33c of different diameters are coaxially and slidably connected, and can be extended and contracted upward along the screw shaft 27. The lower part of the outer large-diameter pipe 33a is fixed to the side surface of the gear case 17a of the auger 17 via a bracket, and the upper end of the innermost small-diameter pipe 33c has a large-diameter portion 33d having the same outer diameter as the large-diameter pipe 33a. It is provided. Furthermore, a locking member 33e having a larger diameter than the large diameter portion 33d is provided at the upper end of the large diameter portion 33d. Furthermore, the upper end outer circumferential portion of the large diameter pipe 33a and the lower end outer circumferential portion of the large diameter portion 33d are chamfered in the circumferential direction, so that when the telescopic rod 33 is retracted, the upper end of the large diameter pipe 33a and the large diameter The lower ends of the portions 33d are in contact with each other, so that both outer circumferential surfaces are smoothly continuous.

The connecting member 34 is constructed around an arm main body 34a passed between the telescopic rod 33 and the swivel joint 30, and includes a guide cylinder 34b having an inner diameter through which the large diameter pipe 33a and the large diameter portion 33d of the telescopic rod 33 can be inserted. , has a holding part (not shown) that holds the coupling 30a side of the swivel joint 30 via a bearing mechanism, and a hose holding part 34c that holds the injection hose 31, and a telescopic rod inside the guide tube 34b. 33 is inserted so as to be movable in the axial direction, and the locking member 33e prevents the guide tube 34b from coming out above the large diameter portion 33d. As a result, the body 30b side of the swivel joint 30 is held unrotatably in a fixed position with the injection hose 31 connected, and the swivel joint 30 is not rotated by the rotating screw shaft 27.

Below, a procedure for improving the ground using the screw shaft 27, which is longer than the leader 15, will be explained using the soil improving machine 11 formed as described above. First, before starting work, the auger 17 is placed above the leader 15 in a working posture with the leader 15 standing vertically, and the intermediate angle shaft portion 27b of the screw shaft 27 is engaged with the chuck mechanism 17b of the auger 17. At the same time, the screw shaft 27 is held rotatably and vertically movably by the steady stop device 25 (FIG. 1). At this time, the upper part of the screw shaft 27 is in a state of greatly protruding above the auger 17, and the lower end of the excavation head 29 is in a state of being located on the ground.

In addition, the connecting member 34 is in a raised position according to the height of the swivel joint 30 connected to the upper end of the screw shaft 27, and accordingly, the telescopic rod 33 is also in the maximum extended state (most extended state). ing. Furthermore, a force is acting on the telescopic rod 33 in the direction of contraction due to the weight of the middle and upper pipes 33b and 33c, but the upper end of the guide tube 34b of the connecting member 34 is in contact with the lower surface of the locking member 33e. This maintains the fully extended state.

In this state, the auger 17 is operated to rotate the screw shaft 27 while lowering it along the leader 15, and at the same time, the ground improvement agent sent through the screw shaft 27 is injected from the tip of the drilling head 29 into the excavation hole. As a result, the earth and sand excavated by the excavation blade 29a of the excavation head 29 and the ground improvement agent are mixed by the stirring blade 29b of the excavation head 29. At this time, the telescoping rod 33 descends together with the auger 17 and the screw shaft 27, so it remains at its maximum extension.

After the auger 17 is lowered to the lower part of the leader 15, the auger 17, which has released its grip on the intermediate corner shaft portion 27b, is raised to regrip the upper corner shaft portion 27b. At this time, the screw shaft 27 is gripped by the fixing means of the steady stop device 25 in order to fix the screw shaft 27 in that position. Furthermore, since the auger 17 disengages from the screw shaft 27 and rises, the amount of protrusion of the screw shaft 27 decreases as the auger 17 rises, and the distance between the auger 17 and the swivel joint 30 gradually increases. Becomes shorter.

Along with this, the telescopic rod 33 is contracted, and the middle and upper pipes 33b and 33c are both housed in the large diameter pipe 33a, and the lower end of the large diameter part 33d provided at the upper end of the small diameter pipe 33c is By coming into contact with the upper end of the large-diameter pipe 33a, the telescopic rod 33 enters the most contracted state (most contracted state).

When the auger 17 further rises in this most contracted state, the telescopic rod 33 rises at the same time as the auger 17, whereas the height of the connecting member 34 holding the swivel joint 30 at the holding portion does not change. The telescopic rod 33 rises through the guide tube 34b. At this time, the guide tube 34b moves from the outer periphery of the large diameter portion 33d to the outer periphery of the large diameter pipe 33a, and further moves to just above the portion of the large diameter pipe 33a fixed to the auger 17.

After the gripping position of the screw shaft 27 is switched to the upper side by moving the auger 17, the screw shaft 27 is lowered while being rotated, and the earth and sand excavated by the excavation blade 29a of the excavation head 29 and the ground improvement agent are mixed with the stirring blade 29b. Mix with Then, after lowering the excavation head 29 to a predetermined depth, the excavation head is pulled out in the reverse order, thereby completing the ground improvement work.

Here, when pulling out the screw shaft 27, the auger 17 that has descended to the lower end of the leader 15 is raised along the leader 15 while gripping the upper corner shaft portion 27b of the screw shaft 27. At this time, the auger 17 and the screw shaft 27 rise at the same time, so the telescopic rod 33 rises while remaining in its most contracted state and the guide tube 34b of the connecting member 34 remaining located on the outer periphery of the large diameter pipe 33a.

After the auger 17 is raised to the top of the leader 15, when the auger 17, which has released its grip on the upper corner shaft portion 27b, is lowered to regrip the intermediate corner shaft portion 27b, the screw shaft 27 does not descend. Since only the auger 17 descends while the connecting member 34 remains located at the upper end of the screw shaft 27, the telescopic rod 33 descends with respect to the guide tube 34b, and the guide tube 34b is removed from the outer circumference of the large diameter pipe 33a. It moves toward the outer periphery of the diameter portion 33d. Then, when the upper end of the guide tube 34b comes into contact with the lower surface of the locking member 33e, the middle and upper pipes 33b and 33c of the telescopic rod 33 are sequentially lifted and extended by the guide tube 34b, and finally they are expanded to the maximum. The state will be as follows.

By the way, when carrying out the soil improvement machine 11 from the site after work, the connection between the swivel joint 30 and the injection hose 31 is released in advance, and only the upper shaft 28 of the screw shaft 27 is gripped by the auger 17 and extended. All lower parts such as the cutting shaft and the drilling head 29 are removed from the upper shaft 28. After that, when the auger 17 is moved to the lower end of the leader 15 (lowering limit position), an activation signal is received from an auger position detection limit switch (not shown), and the leader hoisting cylinder 16 is permitted to contract by a predetermined amount. Hydraulic control is performed to In this way, as shown in FIG. 3, by retracting the leader hoisting cylinder 16 and setting the leader 15 in the transport position in which it lies backwards, it is possible to keep the height dimension low on the loading platform of a transport vehicle such as a low-floor trailer. It is possible.

In this transportation posture of the soil improvement machine 11, the telescopic rod 33 is tilted to a near-horizontal angle together with the leader 15, and maintains the most contracted state. There is a possibility that the telescoping rod 33 will be extended due to inertia force. Therefore, the ground improvement machine 11 is equipped with a rod stopper member 35 that can appropriately restrict the extension of the telescopic rod 33 without impairing workability.

As shown in FIGS. 4 and 5, the rod stopper member 35 has a bracket structure attached to a top plate 36a of a house cover 36 installed on the engine storage house 20 using a plurality of bolts 37, The strength in the pressing direction of the telescopic rod 33 is increased by the pair of left and right side plates 35a, 35a, and the upper part of the front plate 35b has a contact rubber 38 with which the locking member 33e at the tip can come into contact when the telescopic rod 33 is about to extend. is provided. The rod stopper member 35 is specifically arranged in such a position that it does not block the moving direction of the telescopic rod 33 following the up-and-down movement of the leader 15, but blocks the extending direction of the telescopic rod 33 in the transportation posture. That is, the position in the left and right direction is placed on a vertical plane passing through the axis of the telescopic rod 33, and the position in the front and back direction is the same as the telescopic rod 33 in the most contracted state, which moves in an arc around the support shaft (rotation center) 23 of the leader 15. In order to avoid interference, the locking member 33e of the telescopic rod 33 and the contact rubber 38 are placed close to each other with a gap S of, for example, about 20 mm at the transportation position after the arc movement.

In addition, the telescopic rod 33 in the transport position has an inclination angle that matches the inclination angle of the leader 15, in other words, an angle θ such that the extension direction of the telescopic rod 33 is diagonally upward from the horizontal, for example, at an inclination of 5 degrees. Retained. Correspondingly, the rod stopper member 35 is arranged so that the contact surface 38a of the contact rubber 38 faces the extending direction of the telescopic rod 33 by inclining the front plate 35b.

In the soil improvement machine 11 equipped with such a rod stopper member 35, in a working posture with the leader 15 standing vertically, the upper corner shaft portion 27b of the screw shaft 27, that is, the upper shaft 28, is gripped by the auger 17. , the telescopic rod 33 is maintained in its most contracted state by its own weight. However, even if the auger 17 is in the most contracted state, if the auger 17 has not moved to the lower end of the leader 15 (the auger is not stored), the auger position detection limit switch will not detect the position, and the leader 15 cannot be lowered. can't do it. Such a safety device prevents the telescopic rod 33 from coming into contact with the rod stopper member 35 during the transition from the working position to the transporting position.

When the leader hoisting cylinder 16 is retracted while the auger 17 is moved to the lower end of the leader 15 and the leader hoisting cylinder 16 is retracted, the telescopic rod 33 moves above the house 20 as the leader 15 falls down, and the leader hoisting cylinder 16 contracts. At the position where it is activated to its limit, it becomes the transport position. At this time, the telescopic rod 33 has an upward slope along the leader 15 and is held in a position where the locking member 33e faces the abutment rubber 38 of the rod stopper member 35. On the other hand, when the leader 15 is raised forward by extending the leader hoisting cylinder 16, the telescopic rod 33 is still maintained in its most contracted state even in the working position. Thereafter, when assembling the screw shaft 27, the telescopic rod 33 has each of the pipes 33a, 33b, and 33c extended upward in order, and exhibits a function of preventing the swivel joint 30 from rotating in the fully extended state.

As described above, according to the ground improvement machine 11 of the present invention, the moving direction of the telescopic rod 33 following the up-and-down movement of the leader 15 on the upper revolving body 13 is not blocked, and the extending direction of the telescopic rod 33 is blocked in the transportation posture. Since the rod stopper member 35 is provided, the extension of the telescopic rod 33 can be restricted and released quickly and appropriately by a simple operation of raising and lowering the leader 15. This not only reliably prevents the telescopic rod 33 from stretching on the trailer loading platform during transportation, but also reduces the preparation time before starting work and the preparation time when transporting from the site after work is completed. This contributes to improving the safety and work efficiency of those who handle the ground improvement machine 11.

In addition, the rod stopper member 35 has a contact surface 38a made of contact rubber 38, and the contact surface 38a is arranged to face the extension direction of the telescoping rod 33, so that the tip of the telescoping rod 33 can come into contact with it. Therefore, the elastic force of the contact rubber 38 can suppress the impact on the rod stopper member 35, which is also effective in preventing damage to the rod stopper member 35. Furthermore, since the telescoping rod 33 is held in the transportation position at an angle such that its extension direction is diagonally upward rather than horizontal, the telescoping rod 33 is held at an angle such that its extension direction is diagonally upward rather than horizontal. The rod stopper member 35 can be stabilized in its most contracted state, and this also contributes to reducing the size of the rod stopper member 35 and the installation space.

Note that the present invention is not limited to the above-mentioned embodiments, and the rod stopper member is preferably formed from a plate material that is inexpensive and easy to manufacture, but is not limited to this, and may be formed from a shaped steel material such as a square pipe. A combination of these can be used. Further, the contact surface can be formed of a contact rubber, which is an elastic body, or a soft resin, a soft metal such as mild steel, or the like. Furthermore, if the rod stopper member is installed on the house, retrofitting is easy by tightening a blind nut, but this is not the only option. For example, if the telescopic rod becomes longer, it can be adapted. Various installation modes can be considered depending on the specifications of the soil improvement machine, such as installing it on the rear side of the upper revolving structure.

11... Ground improvement machine, 12... Lower traveling body, 13... Upper rotating body, 14... Base machine, 15... Leader, 16... Leader undulating cylinder, 17... Auger, 17a... Gear case, 17b... Chuck mechanism, 17c... Auger drive Hydraulic motor, 17d... Guide gib, 18... Leader support, 19... Operator's cab, 20... Engine storage house, 21... Jack, 22... Counterweight, 23... Support shaft, 24... Top sheave, 25... Steady stop device, 26 ...Guide pipe, 27...Screw shaft, 27a...Chuck groove, 27b...Square shaft, 28...Upper shaft, 29...Drilling head, 29a...Drilling blade, 29b...Stirring blade, 30...Swivel joint, 30a...Coupling, 30b...Body, 31...Injection hose, 32...Stopping device, 33...Extendable rod, 33a, 33b, 33c...Pipe, 33d...Large diameter portion, 33e...Locking member, 34...Connection member, 34a...Arm body, 34b...Guide tube, 34c...Hose holding part, 35...Rod stopper member, 35a...Side plate, 35b...Front plate, 36...House cover, 36a...Top plate, 37...Bolt, 38...Rubber, 38a...Abutment surface

Claims (3)

a base machine in which an upper rotating body is rotatably provided on the upper part of the lower traveling body; a leader provided in the front part of the upper rotating body so as to be able to rise and fall; a rotational drive device that moves up and down along the leader; a screw shaft attached to the drive device; and a swivel joint provided at the upper end of the screw shaft to which a soil improvement agent injection hose is connected; A ground improvement machine including a telescopic rod and connecting the telescopic rod and the swivel joint with a connecting member,
The leader is formed to be able to rise and fall into a working position in which it stands vertically, and a transportation position in which it holds the rotary drive device at its lower end and lies down backwards,
The upper revolving body is provided with a rod stopper member that does not block the moving direction of the telescopic rod according to the up-and-down movement of the leader and blocks the extending direction of the telescopic rod in the transportation posture. Ground improvement machine. The rod stopper member has a contact surface that is arranged to face the extension direction of the telescoping rod in the transportation attitude, and that allows the tip of the telescoping rod to come into contact with the contact surface, and the contact surface is elastic. The soil improvement machine according to claim 1, characterized in that it is formed of a body. 3. The ground improvement machine according to claim 1, wherein the telescopic rod is held at an angle such that the direction of extension is diagonally upward rather than horizontal in the transportation attitude.

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