JP7503816B1 - Swivel anti-rotation device - Google Patents

Abstract

[Problem] To reliably prevent the co-rotation of a swivel, and ensure safety during work. [Solution] A co-rotation prevention device 1 for a rod 3 with a swivel 9 at its upper end when the rod 3 is rotated. The device is composed of a fixed metal fitting 20 fixed to a non-rotating part 9B of the swivel 9 and extending downward therefrom, a shaft member 21 fixed to the lower end of the fixed metal fitting 20 and disposed parallel to the rotation axis of the rod 3, and a driven rotor 22 rotatably provided on the shaft member 21 and contacting the outer surface of the rotating part 9A of the swivel 9, thereby rotating in response to the rotation of the rod 3. A spring member 26 is interposed between a frame 25 that fixes the shaft member 21 and the fixed metal fitting 20, so that the driven rotor 22 is pressed against the outer surface of the rotating part 9A of the swivel 9. [Selected Figure] Figure 3

Description

The present invention relates to a device that prevents a rod with a swivel at its upper end from rotating together with the swivel when the rod is rotated.

A conventional ground improvement method is to use a drilling machine to rotate a rod while penetrating the ground and injecting a ground improvement material to form a columnar improved ground. This type of ground improvement method includes a chemical injection method in which an injection material is infiltrated into the gaps in the ground and the interstitial water or air is replaced with the injection material, thereby bonding the soil particles with the injection material and increasing the soil's adhesiveness, and a high-pressure injection method in which a hardening material is injected into the ground at high pressure, destroying and cutting the ground with the kinetic energy of the injected body, while at the same time replacing or mixing the hardening material with the original ground and hardening it.

The upper end of the rod used in the chemical injection method and high-pressure jet injection method is equipped with a swivel to which an injection hose is connected, so that the injection material and hardener pumped out from the injection pump are supplied to the rod through the injection hose.

Various swivel anti-rotation devices have been developed to prevent the non-rotating part of the swivel to which the injection hose is connected from rotating with the rotating rod, causing the injection hose to become tangled and wrapped around the rod.

For example, the following Patent Document 1 discloses a structure in which a reaction-force receiving arm is extended to the side of the fixed member of the swivel, one end of a wire is connected to this reaction-force receiving arm and hung down, and a wire chuck device is provided in the drive unit to chuck the middle part of the wire. The following Patent Document 2 discloses a device in which a cross member is attached to a swivel placed at the top of a rod, a mechanism is provided to apply tension by wire from both ends of the cross member, and tension is applied to the wire to prevent the swivel from rotating. The following Patent Document 3 discloses a structure in which a guide member that moves independently of the rotation drive unit is provided in the leader, a telescopic member that can be extended and retracted is fixed to the swivel, and the telescopic member is integrated with the guide member via an intermediate support to prevent co-rotation.

Japanese Patent Application Laid-Open No. 10-220158 Japanese Patent Application Laid-Open No. 5-239983 Utility Model Registration No. 3109482

All of the co-rotation prevention devices described in Patent Documents 1 to 3 prevent co-rotation mechanically by extending an arm, cross member, telescopic member, etc. from the swivel and supporting it on a fixed object. However, if the arm, etc., protrudes too far from the swivel, it may be easily damaged if it collides with other machinery, in which case the co-rotation prevention function may no longer work. In addition, there are problems such as the long extended arm getting in the way during assembly and construction work, reducing safety.

The main objective of the present invention is to provide a swivel rotation prevention device that can reliably prevent swivels from rotating together and ensure safety during work.

In order to solve the above problem, the present invention according to claim 1 provides a device for preventing a part of a swivel provided at an upper end of a rod from rotating together with the rod when the rod is rotated to drill a hole or is pulled out, thereby maintaining a non-rotating state, the device comprising:
The device provided is characterized in that it comprises a fixed metal fitting fixed to the non-rotating part of the swivel and extending downward therefrom, an axial member fixed to the lower end of the fixed metal fitting and arranged parallel to the rotation axis of the rod, and a driven rotor which is rotatably mounted on the axial member and rotates in response to the rotation of the rod by contacting the outer surface of the rotating part of the swivel or the outer surface of the rod, and while the driven rotor rotates in response to the rotation of the rod, the rotational speed of the driven rotor is the same as the rotational speed of the rod and the driven rotor is maintained in the same position .

In the invention described in claim 1, a fixed metal fitting is fixed to the non-rotating part of the swivel, and an axial member arranged parallel to the rotation axis of the rod is fixed to the lower end of the fixed metal fitting, and a driven rotor provided rotatably on the axial member rotates following the rotation of the rod by contacting the outer surface of the rotating part of the swivel or the outer surface of the rod. While the driven rotor rotates following the rotation of the rod, the contact position of the driven rotor is maintained in the same position, so that the non-rotating part of the swivel can be reliably prevented from rotating together with the rotation of the rod. In addition, since the fixed metal fitting extends downward from the non-rotating part of the swivel and has a structure in which the driven rotor is provided at its tip, there is no part that protrudes significantly from the swivel, so it does not get in the way during work and ensures safety during work.

The present invention according to claim 2 provides a device for preventing co-rotation of a swivel according to claim 1, in which the driven rotor is pressed against the outer surface of the rotating part of the swivel or the outer surface of the rod by interposing a spring member between the member for fixing the shaft member and the fixed metal fitting, or by interposing a spring member between the non-rotating part of the swivel and the fixed metal fitting.

In the invention described in claim 2 above, by interposing a spring member at a specified position, the driven rotor is pressed against the outer surface of the rotating part of the swivel or the outer surface of the rod, preventing the driven rotor from slipping or spinning freely, and making it easier to maintain the contact position of the driven rotor in the same position.

The present invention relates to claim 3, which provides a device for preventing co-rotation of a swivel as described in claim 1, in which the driven rotor is a roller.

In the invention described in claim 3 above, a roller made of rubber, plastic, or the like is used as the driven rotor.

The present invention according to claim 4 provides a device for preventing co-rotation of a swivel according to claim 1, in which the driven rotor is a gear, and a gear part that meshes with the gear is formed on the outer surface of the rotating part of the swivel or the outer surface of the rod with which the driven rotor is in contact.

In the invention described in claim 4 above, a gear is used as the front vertical driven rotor, and a gear part is provided on the outer surface of the rotating part of the swivel or the outer surface of the rod with which this gear meshes.

As explained above in detail, the present invention can reliably prevent the swivels from rotating together, ensuring safety during work.

FIG. 2 is a side view of an improved device 2 equipped with a swivel co-rotation prevention device 1 according to the present invention. This is a procedure diagram for the ground improvement method. 1 is an enlarged cross-sectional view of a swivel co-rotation prevention device 1 according to the present invention (enlarged view of part III in FIG. 1 ). FIG. 4 is a top view of FIG. 4 is a view taken along the line VV in FIG. 3. 4 is a cross-sectional view of the driven rotor 22 at a contact point. FIG. FIG. 11 is an enlarged cross-sectional view of a modified example of a swivel co-rotation prevention device 1. FIG. 8 is a top view of FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 7.

The following describes in detail the embodiments of the present invention with reference to the drawings.

As shown in FIG. 1, the swivel co-rotation prevention device 1 according to the present invention is used in an improvement device 2 used in ground improvement methods such as chemical injection and high-pressure jet injection.

As the improvement device 2, a normal boring machine (drilling machine) for boring holes in the ground can be widely used. The improvement device 2 shown in FIG. 1 includes a rod 3 with a bit at its tip (lower end), a spindle 4 with a chuck for holding the rod 3, a drive transmission unit 5 with a gear group and a clutch, a hydraulic motor 6 that rotates with hydraulic energy, and a hydraulic unit 7 and a power board 8 that supply hydraulic pressure for driving the hydraulic motor 6. The drive transmission unit 5 rotates the spindle 4 and moves it up and down by the rotation of the hydraulic motor 6, and the rod 3 is rotated to excavate the ground with the bit attached to its tip. When excavating with the bit, mud water pumped from a mud tank (not shown) is sprayed from the tip of the bit via the swivel 9 and the rod 3 from the joint 10 or 11 to which an injection hose attached to the swivel 9 at the upper end of the rod 3 is connected, in order to cool the bit and transport the excavated soil to the ground.

The procedure for the ground improvement method using the improvement device 2 will now be explained with reference to Figure 2. Figure 2 shows the construction procedure for the chemical injection method as an example of a ground improvement method. Here, the chemical injection method will be explained as an example, but high-pressure jet injection method can also be carried out using standard procedures.

Figure 2 shows the construction procedure for the double-pipe strainer method (multi-phase), which is one of the chemical injection methods. The double-pipe strainer method first pumps in a fast-setting chemical solution to block areas where the chemical solution is likely to be artificially disturbed, and this packing effect prevents the next chemical solution from diffusing. After that, a slow-setting chemical solution is injected, allowing it to penetrate uniformly into the gaps between the soil particles in the required areas.

The specific construction procedure is as follows: in the first step, as shown in Figure 2 (A), drilling water is sprayed from the tip of the rod 3 while drilling to a specified depth.

Then, as the second step, as shown in FIG. 2(B), a primary injection is performed in which a fast-setting chemical liquid (liquid A) is injected from an injection hose connected to a joint 10 of a swivel 9 provided at the upper end of the rod 3. This seals the area around the injection tube and performs a rough injection.

Then, as the third step, as shown in FIG. 2(C), a secondary injection is performed in which a slow-setting chemical solution (liquid B) is injected from an injection hose connected to the swivel joint 11. This allows the chemical solution to penetrate uniformly into the gaps between the soil particles.

As a fourth step, as shown in FIG. 2(D), the second and third steps are repeated each time the rod 3 is withdrawn in stages in the range of 20 to 50 cm, thereby injecting the drug solution into a specified area.

The swivel co-rotation prevention device 1 of the present invention is a device that prevents the part of the swivel 9 at the upper end to which the injection hose is connected from rotating with the rotation of the rod 3 when the rod 3 is rotated to drill a hole or to pull it out, thereby maintaining a non-rotating state.

As shown in Figures 3 to 5, the co-rotation prevention device 1 is composed of a fixed metal fitting 20 that is fixed to the non-rotating part of the swivel 9 and extends downward therefrom, a shaft member 21 that is fixed to the lower end of the fixed metal fitting 20 and arranged parallel to the rotation axis of the rod 3, and a driven rotor 22 that is rotatably mounted on the shaft member 21 and rotates in response to the rotation of the rod 3 by contacting the outer surface of the rotating part of the swivel 9.

As shown in FIG. 6, in the co-rotation prevention device 1, the driven rotor 22, which is in contact with the outer surface of the rotating part 9A of the swivel 9 that rotates in conjunction with the rotation of the rod 3, rotates in the opposite direction to the rotation direction of the rod 3. At this time, while the driven rotor 22 rotates in conjunction with the rotation of the rod 3, the rotation speed of the driven rotor 22 is the same as the rotation speed of the rod 3, and the driven rotor 22 is held in the same position, unless the resistance force between the rotating part 9A and the non-rotating part 9B of the swivel 9 or the resistance force between the driven rotor 22 and the shaft member 21 becomes large. In this way, since the contact point of the driven rotor 22 is always held in the same position, the non-rotating part 9B of the swivel 9 is held in a fixed position, and the injection hose can be reliably prevented from becoming entangled and wrapped around the rod 3 due to co-rotation.

In addition, the co-rotation prevention device 1 according to the present invention does not have any components that protrude significantly from the outer circumference of the swivel 9 or that hang down significantly from the swivel 9, and since the shaft member 21 and driven rotor 22 are attached to the fixing bracket 20, they do not get in the way during work and can be used safely.

Furthermore, since the co-rotation prevention device 1 according to the present invention is not fixed to an external fixed body, the joint parts 10, 11 to which the injection hose provided on the non-rotating part 9B of the swivel 9 is connected can be fixed in a position facing in any direction. This eliminates the need to determine in advance the relationship between the direction in which the injection hose extends and the installation position of the improvement device 2, allowing for flexible work planning according to on-site conditions and improving workability.

The swivel 9 is composed of a rotating part 9A that is coaxially connected to the upper end of the rod 3 and rotates together with the rod 3, and a non-rotating part 9B that is located above it and has a bearing 12 between it and the rotating part 9A, thereby significantly reducing the transmission of rotational force from the rotating part 9A. The non-rotating part 9B is provided with coupling parts 10 and 11 to which injection hoses for injecting chemical solutions (liquid A and liquid B) are connected.

The fixing bracket 20 is a metal fitting formed by bending a metal plate into a hook shape, with one end fixed to the outer surface of the non-rotating part 9B of the swivel 9 and the other end hanging down as a free end. The end fixed to the swivel 9 has two insertion holes spaced apart in the circumferential direction of the rod 3 for inserting the fixing bolt 23, and the other free end has two insertion holes spaced apart in the circumferential direction of the rod 3 for inserting the connecting fixing bolt 24 of the member that fixes the shaft member 21.

The shaft member 21 and driven rotor 22 have a structure similar to that of a sliding door wheel, with the shaft member 21 straddling two opposing faces of a frame body 25 that has a U-shaped cross section, and the driven rotor 22 being rotatably mounted on the shaft member 21.

The frame body 25 that fixes the shaft member 21 may be fixed directly to the fixed metal fitting 20 by the fixing bolt 24, but as shown in Figures 3 and 5, it is preferable to interpose a spring member 26 between the frame body 25 and the fixed metal fitting 20 so that the driven rotor 22 is pressed against the outer surface of the rotating part 9A of the swivel 9. In more detail, the shaft portion of the fixing bolt 24 is extended to position the frame body 25 away from the fixed metal fitting 20, and a coil spring (spring member 26) that fits around the shaft portion of the fixing bolt 24 is provided at the separated portion, thereby interposing the spring member 26 between the frame body 25 and the fixed metal fitting 20. To place the driven rotor 22 in pressure contact with the outer surface of the rotating part 9A of the swivel 9, the frame 25 is pushed outward against the biasing force of the spring member 26, while the driven rotor 22 is brought into contact with the outer surface of the rotating part 9A of the swivel 9, and then the pressure of the pressure contact is adjusted by adjusting the nut that is screwed onto the tip of the fixing bolt 24.

In this way, the driven rotor 22 is pressed against the outer surface of the rotating part 9A of the swivel 9 by the biasing force of the spring member 26, so the frictional force between the driven rotor 22 and the outer surface of the rotating part 9A of the swivel 9 increases, making it less likely that slippage or freewheeling will occur between the driven rotor 22 and the outer surface of the rotating part 9A of the swivel 9, and making it easier for the driven rotor 22 to be held in the same position. Even if a protrusion is formed on the outer surface of the rotating part 9A of the swivel 9, or a foreign object is interposed between the driven rotor 22 and the outer surface of the rotating part 9A of the swivel 9, causing the driven rotor 22 to jump outward, the biasing force of the spring member 26 absorbs the impact and allows the driven rotor 22 to quickly return to the state in which it is pressed against the outer surface of the rotating part 9A of the swivel 9.

As shown in Figures 7 to 9, the mechanism for pressing the driven rotor 22 against the outer surface of the rotating part 9A of the swivel 9 can also be achieved by interposing a spring member 26 between the non-rotating part 9B of the swivel 9 and the fixed metal fitting 20. More specifically, as shown in Figures 7 and 8, the fixed metal fitting 20 is placed away from the outer surface of the non-rotating part 9B of the swivel 9, a fixed bolt 23 is provided in the center, guide shafts 27, 27 are placed on both sides of the fixed metal fitting 20, and a coil spring (spring member 26) is fitted onto the guide shaft 27 between the fixed metal fitting 20 of the guide shaft 27 and the outer surface of the non-rotating part 9B of the swivel 9. At this time, the frame 25 and the fixed metal fitting 20 are directly fixed by the fixed bolt 24. In this embodiment, the fixing bracket 20, frame 25, shaft member 21, and driven rotor 22 are integrated and receive the biasing force of the spring member 26, so that the driven rotor 22 is pressed against the outer surface of the rotating part 9A of the swivel 9.

The driven rotor 22 in the illustrated example is a roller made of rubber, plastic, metal, etc. This driven rotor 22 is subject to wear due to contact with the outer surface of the rotating part 9A of the swivel 9, so it is subject to regular maintenance and replaced with a new one as necessary.

A gear may be used as the driven rotor 22. This gear is an external gear that rotates around the shaft member 21 as a rotation axis, and a gear part that meshes with this gear is formed on the outer surface of the rotating part 9A of the swivel 9 with which this gear comes into contact. By using a gear as the driven rotor 22, the driven rotor 22 can reliably rotate following the rotation of the rotating part 9A without slippage or misalignment with the outer surface of the rotating part 9A of the swivel 9.

[Other examples]
In the above embodiment, the driven rotor 22 is disposed so as to be in contact with the outer surface of the rotating portion 9A of the swivel 9, but it may be disposed so as to be in contact with the outer surface of the rod 3.

1... Swivel co-rotation prevention device (co-rotation prevention device), 2... Improved device, 3... Rod, 4... Spindle, 5... Drive transmission part, 6... Hydraulic motor, 7... Hydraulic unit, 8... Power board, 9... Swivel, 10, 11... Joint part, 12... Bearing, 20... Fixing metal fitting, 21... Shaft member, 22... Driven rotor, 23, 24... Fixing bolt, 25... Frame, 26... Spring member

Claims (4)

A device for preventing the rotation of a swivel to keep a non-rotating state by preventing a portion of the swivel to which an injection hose is connected from rotating with the rotation of the rod when the rod is rotated to drill a hole or to pull out the rod, comprising:
A swivel co-rotation prevention device comprising: a fixed metal fitting fixed to the non-rotating part of the swivel and extending downward therefrom; an axial member fixed to the lower end of the fixed metal fitting and arranged parallel to the rotation axis of the rod; and a driven rotor rotatably mounted on the axial member and rotating in response to the rotation of the rod by contacting the outer surface of the rotating part of the swivel or the outer surface of the rod, wherein while the driven rotor rotates in response to the rotation of the rod, the rotational speed of the driven rotor is the same as the rotational speed of the rod and the driven rotor is maintained in the same position . The swivel co-rotation prevention device according to claim 1, in which the driven rotor is pressed against the outer surface of the rotating part of the swivel or the outer surface of the rod by interposing a spring member between the member that fixes the shaft member and the fixed metal fitting, or by interposing a spring member between the non-rotating part of the swivel and the fixed metal fitting. The swivel co-rotation prevention device according to claim 1, wherein the driven rotor is a roller. The swivel co-rotation prevention device according to claim 1, wherein the driven rotor is a gear, and a gear part that meshes with the gear is formed on the outer surface of the rotating part of the swivel or the outer surface of the rod with which the driven rotor is in contact.

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