JPH108459A - Pile coupling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a quite new technology for preventing reverse screw- engagement of male and female couplings to be loosened even in a non-earth discharge rotary burying work method by providing a reverse loosening stop mechanism of a specified structure between the male coupling and the female coupling. SOLUTION: A coupling structure of pile main bodies 1, 2 is such that a male coupling 3 having a screw part 7 on the outer peripheral surface and a female coupling 4 having a screw part 9 on the inner peripheral surface are connected to each other by screw engagement. A pair of ring-like reverse loosening stop member 12, 13 having several downhill grades projected in several places in the screw fastening direction on one surface, which are mutually engaged with each other, are respectively provided on the forward end part of the male coupling 3 and the inner bottom part 10 of the female coupling 4, and the screw-fitting of the male and female couplings 3, 4 is kept from being loosened by the operation of the ring-like reverse loosening stop members 12, 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a foundation pile for civil engineering and construction,
Pertaining to pile joints used for anchors for earth work (hereinafter simply referred to as piles), especially for piles in sites where there is only a narrow carry-in route in overcrowded cities, and for places where it is difficult to carry in construction equipment The present invention relates to a pile joint by screw connection between a male joint and a female joint.

[0002]

2. Description of the Related Art Steel pipe piles are easier to construct than precast concrete piles and are extremely light in weight compared to precast concrete piles exhibiting similar strength. It has been widely used as a foundation pile for bridges and bridge projects where construction work must be completed in a short period of time, or in a short time.

[0003] However, when used as a support pile, the depth to a stable rock mass varies depending on the location, and it is manufactured in a certain length, like a ready-made concrete pile, until the required depth is reached. Had to be extended by welding. In addition, the structure of a welded joint requires highly skilled craftsmen to obtain the strength of the joint by welding, and such welding work is significantly affected by the weather and the environment, so that the reliability is significantly reduced. There was a missing problem.

[0004] In order to improve the disadvantages of the above-mentioned joints by the welding method, for example, Japanese Utility Model Laid-Open No. 60-195328, Japanese Patent Publication No. 50-25255, Japanese Utility Model No. 40-6043, and Japanese Utility Model Application No. 61-84734. Gazette, Shokai 56-1
As described in JP-A-30034, JP-A-8-60652, JP-B-56-36248, etc., various techniques of a threaded joint for connecting a male joint and a female joint using screws have been developed.

[0005] Briefly describing the above-mentioned known technique, the technique described in Japanese Utility Model Laid-Open Publication No. Sho 60-19528 relates to a joint part of a pre-made concrete pile using a threaded joint.
Use the anti-rotation hardware and bolts to fix it,
The male joint and female joint attached to the lower pile that was preceded and the upper pile that was added are fixed with detent hardware,
A configuration in which the screw engagement is not loosened is disclosed.

Japanese Patent Publication No. 25255/1985 discloses a method of filling a metal, cement or synthetic resin which is solidified without shrinkage after being joined to the clearance of a female screw and a male screw and then injected in a molten state. Further, in Japanese Utility Model Publication No. 40-6043, a circumferential groove is provided on the inner peripheral portion of the hollow base pile, and a protruding bar that can be fitted into the hollow base pile is protruded from the lower end of the connection pile. There is disclosed a connection device around which a metal wire that can be fitted into the circumferential groove is attached.

Japanese Utility Model Application Laid-Open No. 61-84734 discloses that a male joint and a female joint, each of which can be screw-connected, are attached to the pile ends of upper and lower piles, and the upper and lower piles are screwed together to connect the upper and lower piles. The connecting structure is shown. In addition, 56-1
Japanese Patent No. 30034 discloses a configuration in which screws are provided on the inner peripheral surfaces of upper and lower piles, and a joint hardware having a screw on the outer peripheral surface is screwed into the inner peripheral surfaces of the upper and lower piles, thereby connecting the upper and lower piles via the joint hardware. It is shown.

Japanese Unexamined Patent Publication No. Hei 8-60652 discloses a configuration of a joint using a taper screw, although there is no reverse rotation locking mechanism. Further, Japanese Patent Publication No. 56-36248 proposes a structure in which a rotary cylinder provided with a plurality of cam-shaped projections is incorporated in a joint, and the joint is disengaged by rotating the rotary cylinder from outside.

[0009]

However, the above-mentioned many known techniques have the following problems, respectively. That is, the technology disclosed in Japanese Utility Model Laid-Open No.
Because it is a ready-made concrete pile and a pile used in the pre-boring method, the pile itself is directly received by the forward and reverse rotation torque, and the non-discharged rotary burial method is applied. In addition, there has been a problem that the non-rotating metal must be attached using bolts or the like after the joining, which does not save labor.

The technique disclosed in Japanese Utility Model Publication No. 50-25255 is
In the experiment, the clearance was set at 0.5 m to ensure the jointability and the verticality after joining.
m, and filled with a synthetic resin adhesive. As in the previous section, the non-discharged rotary burial method has a problem that the resin is sheared due to the action of a large torque and is not practical. Further, Japanese Utility Model Publication No. 40-6043, Japanese Utility Model Application Laid-Open No. 61-84734, Japanese Utility Model Application Publication No. 56-130034, and Japanese Patent Application Laid-Open No. H8-6-6.
In any of the techniques disclosed in Japanese Patent No. 0652, the joint portion is elastically deformed when a strong force is applied in a short time such as an earthquake, so that the connection of the threaded portion is detached due to crossing a mountain or the like. There was a problem.

The technology disclosed in Japanese Patent Publication No. 56-36248 is
It is necessary to make the manufacturing accuracy considerably high, and as a structure used for the joint of the foundation pile, it is necessary to make expensive parts, and there is a problem that it is economically unsuitable.

[0012] Among the above-mentioned known techniques, Japanese Utility Model Application Laid-Open No. 60-195.
The technology disclosed in Japanese Patent No. 328 has a reverse rotation locking mechanism having a structure in which a non-rotating metal member is attached to a joint after being joined, but since it is not a pile for a non-discharged rotary burial method, it is a full-fledged method. No reverse rotation prevention mechanism was provided. Further, the technique disclosed in Japanese Patent Application Laid-Open No. Hei 8-60652 is a technique for connecting a male joint with a tapered screw, but does not include a reverse rotation stopping mechanism at all.

The present invention is a completely new technique developed in view of the above-mentioned many problems in the prior art, and particularly comprises a reverse rotation preventing mechanism having a specific structure provided between a male joint and a female joint. It is another object of the present invention to provide a completely new pile joint technique in which the screw thread of the male and female joints is prevented from being reversed and loosened even in the non-discharged rotary burial method.

The inventors of the present invention have invented various structures of a reverse rotation preventing mechanism that can be used for a pile joint over many years, and at the same time, have investigated a known technique relating to the reverse rotation preventing mechanism. JP-A-60-21113, JP-A-59-40007, JP-A-5-332
It has been found that the techniques disclosed in Japanese Patent Publication No. 338 and Japanese Utility Model Laid-Open Publication No. 7-38733 are known.

That is, Japanese Patent Application Laid-Open No. 60-211113 discloses a technique in which the structure of the skirt portion is taken into consideration so that the seat pressure of the nut can be made axisymmetric, but the area of the surface where the male and female are joined is considered. Therefore, there is a problem that the male and female end faces of a joint having a practical size cannot be formed as a threaded joint for piles. Japanese Patent Application Laid-Open No. 59-40007 discloses a technique that utilizes a residual load generated when a self-tapping screw is screwed in to prevent return. At a low torque, the locking could not produce any effect.

Japanese Patent Application Laid-Open No. 5-332338 discloses that
This is a technology that uses the frictional force of the washer by combining two types of screws with different pitches and uses the difference in the amount of lead to prevent loosening. There was a problem that was difficult. Further, Japanese Utility Model Laid-Open No. 7-38733 discloses a technique of using a washer and a cam mechanism together to prevent loosening due to a difference in the amount of lead. This technique is also disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 5-332338. This is merely a modification of the technique described above, and there is a problem that it is difficult to use it as it is built in a joint.

As described above, conventional techniques for small parts such as bolts and nuts have been considered, and any of the techniques can be used as it is as a reverse rotation preventing mechanism for a steel pipe pile composed of a threaded joint. Did not exist.

[0018]

A pile joint according to the present invention comprises:
This is a completely new technology which is a radical improvement of the above-mentioned conventional problem, and the gist of the first invention is that a male joint and a female joint are mutually screwed in a joint capable of connecting ready-made piles to each other. It is a pile joint characterized in that the male joint and the female joint are connected to each other and are provided with a reverse rotation preventing mechanism.

The gist of the second invention of the present invention is that, when the male joint and the female joint are connected to each other, the distal end of the female joint and the outer diameter base of the male joint press against each other, and The pile joint according to the first invention, characterized in that the pile joint and the inner bottom of the female joint are pressed against each other.

The gist of the third invention of the present invention resides in that one of the pair of ring-shaped reverse rotation stoppers, of a pair of ring-shaped reverse rotation stoppers projecting at several places in the direction of tightening screws that can be engaged with each other, is provided. A first invention wherein the stop member is provided at the tip of the male joint or the inner bottom of the female joint, and the other ring-shaped reverse rotation preventing member is provided at the inner bottom of the female joint or the tip of the male joint. And the pile joint of any one of the second inventions. In addition, the gist of the fourth invention is that one of the pair of ring-shaped reverse rotation stopping members, which is formed by a pair of ring-shaped reverse rotation stopping members that project several places in the tightening direction of screws that can mesh with each other, is male. A first invention characterized in that it is provided at the outer diameter base of the joint or at the tip of the female joint, and the other ring-shaped reverse rotation preventing member is provided at the tip of the female joint or at the outer diameter base of the male joint. The pile joint according to any one of the second inventions.

Furthermore, the gist of the fifth invention of the present invention is that one ring-shaped reverse rotation preventing member having several downward slopes projecting in the screw tightening direction is connected to the distal end portion of the female joint or the inner bottom portion or the outer diameter of the male joint. Attached to the base or the tip, and formed on the outer diameter base or the tip of the male joint or the tip or the inner bottom of the female joint, to form an uneven surface that can mesh with the uneven surface of the ring-shaped reverse rotation preventing member. The pile joint according to any one of the first and second inventions, characterized in that:

[0022]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A and FIG. 1B show a structure of a pile joint according to a first embodiment of the present invention. FIG. 2 is a perspective view showing an example of a ring-shaped reverse rotation preventing member used in the first embodiment of FIG. 1, and FIGS. 3A and 3B are second embodiments according to the present invention. FIGS. 4A and 4B are longitudinal cross-sectional views showing the structure of a pile joint according to a third embodiment of the present invention, and FIGS. B) is a longitudinal sectional view showing the structure of the pile joint of the fourth embodiment according to the present invention.

FIGS. 6A and 6B are longitudinal sectional views showing the structure of a pile joint according to a fifth embodiment of the present invention, and FIGS.
(B) is a longitudinal sectional view showing a structure of a pile joint according to a sixth embodiment of the present invention, and FIG. 8 is a torsion test of a screw type pile joint having a reverse rotation preventing mechanism according to the first embodiment of the present invention. FIG. 9 (A) is a graph showing the results of FIG.
(B) is a diagram showing a force relationship on a slope surface of the reverse rotation relaxing mechanism.

In FIGS. 1 (A) and 1 (B), reference numerals 1 and 2 denote steel pipe pile bodies, respectively, and a cylindrical male joint 3 is attached to an end of the pile body 1; A cylindrical female joint 4 is attached to an end of the main body 2. The outer peripheral wall of the male joint 3 is provided with a step 5 to which the end of the pile body 1 can be fitted and an outer diameter base 6 to which the tip of the female joint 4 can abut. A screw portion 7 is provided on the outer peripheral surface of the small diameter portion.

The outer peripheral wall of the female joint 4 is provided with a step 8 to which the pile main body 2 can be fitted. On the inner peripheral surface of the female joint 4, a screw portion 9 that can be screwed with the screw portion 7 of the male joint 3 is provided. When the male joint 3 and the female joint 4 having the above-described structure are connected to each other, the distal end of the female joint 4 comes into contact with the outer diameter base 6 of the male joint 3 and at the same time, the male joint 3 Of the female joint 4 is abutted against the inner bottom 10 of the female joint 4, and the male joint 3 and the female joint 4 are pressed against each other at these two places.

In the above embodiment, the outer diameter base 6 of the male joint 3 is formed so as to have a plane (standing plane) perpendicular to the longitudinal direction of the male joint 3. The upright plane of the outer diameter base 6 has a wall thickness equal to or larger than the wall thickness of the pipe section of the pile bodies 1 and 2. Further, a V-groove groove 11 used for welding is provided in a connection outer peripheral portion between the pile main bodies 1 and 2 and the male and female joints 3 and 4.

Next, in FIGS. 1 and 2, reference numeral 12 denotes a first ring-shaped reverse rotation stopping member, as shown in FIG.
The bottom surface is formed of a ring body that can be fitted into the inner bottom portion 10, and one surface 12 a thereof is provided with an uneven surface having a plurality of circumferentially protruding downward gradients in the screw tightening direction. The one back 12b is non-slip.
Due to this non-slip, the friction of the one side 12b is reduced.
It is considered to be larger than a. The non-slip member can be formed by press-fitting a spherical object made of a high-strength material into one of the back surfaces 12b of the first ring-shaped reverse rotation preventing member 12, or by raising a bead by welding. In FIG. 1 (B), the concave portion into which the convex portion of the one back surface 12b can be fitted is formed by the distal end portion of the male joint 3 and the inner bottom portion 1 of the female joint 4.
However, the concave portion is formed by press-fitting the convex portion, and does not need to be provided in advance.

In FIG. 1, reference numeral 13 denotes a second ring-shaped reverse rotation stopping member, which is formed of a ring body having the same diameter as the first ring-shaped reverse rotation stopping member 12 as shown in FIG. The one surface 13a is provided with a symmetrical uneven surface which can mesh with the uneven surface of the first ring-shaped reverse rotation preventing member, and the one back surface 13b is provided with a non-slip surface.

In FIGS. 1 and 2, the first ring-shaped reverse rotation preventing member 12 and the second ring-shaped reverse rotation preventing member 13 are fitted in the inner bottom portion 10 of the female joint 4, respectively. The one surface 12a of the first ring-shaped reverse rotation preventing member 12 and the one surface 12a of the second ring-shaped reverse rotation preventing member 13 are meshed with each other. Also, one back 12 of the first ring-shaped reverse rotation preventing member 12 and the second ring-shaped reverse rotation preventing member 13 are provided.
b and 13b are respectively engaged with the upright surface of the inner bottom portion 10 of the female joint 10 and the end surface of the distal end portion of the male joint 3 so as not to slide.

Accordingly, since the pile bodies 1 and 2 are connected via the male and female joints 3 and 4 and the first ring-shaped reverse rotation preventing member 12 and the second ring-shaped reverse rotation preventing member 13, Even when a reverse force is applied to the male and female joints 3, 4 screwed by the screw portions 7, 9, the first ring-shaped reverse rotation preventing member 12 is also provided.
And the second ring-shaped reverse rotation preventing member 13 are meshed with each other, so that there is no loosening between the male joint 3 and the female joint 4.

In the first embodiment of the present invention shown in FIG. 1, the first ring-shaped reverse rotation stopping member 12 and the second ring-shaped reverse rotation stopping member 13 are respectively connected to the inner bottom 10 of the female joint 4. And between the male joint 3 and the distal end thereof.
As shown in (A) and (B), the first ring-shaped reverse rotation stopping member 14 and the second ring-shaped reverse rotation stopping member 15 are connected between the distal end of the female joint 4 and the outer diameter base 6 of the male joint 3. It is also possible to insert and configure.

That is, the first ring-shaped reverse rotation stopping member 14 and the second ring-shaped reverse rotation stopping member 15 of the second embodiment shown in FIGS. 3A and 3B have male and female outer diameters. The outer diameter of the joints 3, 4 or the pile bodies 1, 2 is equal to the inner diameter of the male joint 3
Has an inside diameter through which the screw portion 7 can be inserted. Also in the case of the second embodiment, the first ring-shaped reverse rotation preventing member 14 and the second
One and back surfaces 14b and 15b of the ring-shaped reverse rotation preventing member 15 are respectively engaged with the distal end of the female joint 4 or the outer diameter base 6 of the male joint 3 so as not to slip. Also in the case of the second embodiment, similarly to the first embodiment, the first ring-shaped reverse rotation preventing member 14 and the second ring-shaped reverse rotation preventing member 15 are formed between the outer peripheral portions of the male and female joints 3 and 4. Since the reverse rotation locking mechanism is provided, no loosening occurs between the male and female joints 3 and 4.

In the first embodiment and the second embodiment shown in FIGS. 1 and 3, a pair of ring-shaped reverse rotation stopping members 1 are respectively provided.
Male-female joints 3, 4 using a combination of 2, 13, 14, 15
4 (A), (B), 5 (A), (B), FIG. 6 (A), and FIG.
As shown in FIGS. 7B, 7A, and 7B, the third, fourth, fifth, and sixth embodiments respectively show one type of ring-shaped reverse rotation stopping member 16, 17. , 18 and 19 can prevent the male and female joints 3 and 4 from loosening in reverse rotation.

That is, in the third embodiment shown in FIGS. 4A and 4B, the same type of ring-shaped reverse rotation stopper 12 as the first ring-shaped reverse rotation stopper 12 used in the first embodiment is used. Stop member 16
The ring-shaped reverse rotation preventing member 16 is fitted to the inner bottom portion 10 of the female joint 4, and is provided on one surface 16 a of the ring-shaped reverse rotation preventing member 16 on the end surface itself of the distal end portion of the male joint 3. An uneven surface 3a capable of meshing with the uneven surface is formed, and the uneven surface 3a of the male joint 3 and one surface 16a of the ring-shaped reverse rotation preventing member 16 are formed.
Are engaged with each other to prevent reverse loosening of the male and female joints 3, 4.

In the fourth embodiment shown in FIGS. 5A and 5B, a ring-shaped reverse rotation stopping member of the same type as the second ring-shaped stopping member 13 used in the first embodiment. 17, the ring-shaped anti-rotation member 17 is attached to the distal end of the male joint 3, and the surface of the inner bottom portion 10 of the female joint 4 is provided on one surface 17a of the ring-type anti-rotation member 17. An uneven surface 10a that can mesh with the surface is formed, and the uneven surface 10a of the inner bottom portion 10 of the female joint 4 and one surface 17a of the ring-shaped reverse rotation preventing member 17 are meshed with each other, whereby the male-female joint 3,
4 can be prevented from loosening in the reverse direction.

In the fifth embodiment shown in FIGS. 6A and 6B, a ring-shaped reverse rotation stopper of the same type as the first ring-shaped reverse rotation stopper member 14 used in the second embodiment. The ring-shaped reverse rotation preventing member 18 is attached to the distal end portion of the female joint 4 using a member 18 and provided on one surface 18a of the ring-shaped reverse rotation preventing member 18 on the outer surface of the outer diameter base 6 of the male joint 3 itself. The male-female joint 3 is formed by engaging the uneven surface 6a of the male joint 3 with the uneven surface 6a of the outer diameter base 6 and the one surface 18a of the ring-shaped reverse rotation preventing member 18. , 4
Can be prevented from becoming loose.

In the sixth embodiment shown in FIGS. 7A and 7B, the second ring-shaped reverse rotation preventing member 15 of the second embodiment is used.
A ring-shaped reverse rotation preventing member 19 of the same type as that described above is used. The ring-shaped reverse rotation preventing member 19 is attached to the outer diameter base 6 of the male joint 3 and the ring-shaped reverse rotation preventing member The male-female joint 3 is formed by forming an uneven surface 4a that can mesh with the uneven surface provided on one surface 19a of the stop member 19, and meshing the uneven surface 4a with the one surface 19a of the ring-shaped reverse rotation preventing member 19. , 4 can be prevented from becoming loose.

As described above, the ring-shaped reverse rotation preventing members 12, 13, 14, 15, 16, 17, 1 used in the present invention.
8, 19, one side 12b, 13b, 14b, 15b, 1
Each of 6b, 17b, 18b, and 19b is provided with a non-slip. These ring-shaped reverse rotation preventing members 12, 1
One side 12 of 3,14,15,16,17,18,19
b, 13b, 14b, 15b, 16b, 17b, 18
b, 19b, if no means for increasing friction is taken, one surface 12a, 13a, 14a, 15a, 16a, 17a,
Because the frictional resistance due to the meshing of 18a and 19a is large,
Sliding occurs on the back side, and does not serve as a locking ring.

Therefore, as described above, the single-sided surfaces 12b, 13
b, 14b, 15b, 16b, 17b, 18b, 19b
In order to further increase the frictional force, it is necessary to provide means such as embossing the back surface by cold forming, spraying another metal, or embedding another object in the back surface.

As described above, the male joint 3 and the female joint 4 are pressed against each other at two places, so that the connection of the pile joint can be provided with a large strength. That is,
As shown in FIGS. 1, 3 to 7, the distal end of the female joint 4 and the outer diameter base 6 of the male joint 3 are pressed against each other, and the distal end of the male joint 3 and the inner bottom 10 of the female joint 4 are also pressed. By doing this, it is possible to obtain a strength of 30% in final strength as compared with a pile joint having a structure that presses at one place.

When the torsion test was performed on the pile joint of the first embodiment according to the present invention, the results shown in the graph of FIG. 8 were obtained. That is, this graph shows the process in which a torque of about 3 ton-m is applied to the pile joint to perform fastening, and then reverse torque is applied to loosen the joint. As is clear from this graph, the tightening torque is about 3 tons-
It was found that joints tightened at m did not loosen when subjected to a reverse torque of about 5 ton-m.

FIG. 9 (A) is a view for explaining the operation of the reverse rotation stopping mechanism. The figure shows the case where the lead of the screw of the pile joint is set to 6 mm and the lead of the ring-shaped reverse rotation stopping member is set to 48 mm. The explanation is as follows. The lead is the amount that the screw advances when rotated by 360 degrees. For example, assuming that a pair of ring-shaped reverse rotation preventing members acted when relatively shifted by 15 degrees, the screw is loosened by 0.25 mm.
It is clear that the ring-shaped reverse rotation preventing member is loosened by 2 mm, and the difference of 1.75 mm acts on the thread portion of the male-female joint as a binding force.

FIG. 9 (B) is a diagram showing the force relationship on the inclined surface of the reverse rotation preventing mechanism, and shows the frictional resistance required on one side of the ring-shaped reverse rotation preventing member. It is a figure showing a relation. The non-slip on one surface of the ring-shaped reverse rotation preventing member has an axial force W generated by a screw tightening force and an angle of the gradient, as apparent from the relationship of the gradient surface in FIG. 9B. It is given as the relationship between α ° and the coefficient of friction μ of the surface. That is, F = μ + W between the above symbols.
× tan α. From this, it is necessary to set the frictional resistance required for the slip prevention on one side to give a numerical value larger than this value, and the result of the experiment is F = Cn
+ Tan 5.71 was found. Here C
Is the frictional force per non-slip, and n is the number of non-slip installed.

As shown in the examples, the function of the non-slip on one surface was provided by press-fitting steel balls. The press-fitted steel ball can exhibit the following effects, unlike a fixed, for example, a cold-formed raised surface or a non-slip surface by thermal spraying or the like. That is, the steel ball is processed by balancing the bearing surface with the axial force by the relative mechanical properties with the workpiece, that is, the hardness and softness of the surface, etc. It is clear that the anti-slip function occurs at the position where the anti-slip steel ball rolls between the anti-slip member and the workpiece according to the situation where the steel ball is placed, and balances the frictional force. It is.

The ring-shaped reverse rotation preventing member according to the present invention includes:
Because of the above-described effects, it is clear that a constant force can be generated anywhere on the circumference of the inclined surface of the ring-shaped reverse rotation stopping member, thereby increasing the stopping effect. . Therefore, by using a screw-type joint having a ring-shaped reverse rotation locking mechanism having the above-described structure, work such as welding on site or attaching a detent is unnecessary. Therefore, the worker can concentrate on only the joining work, and the work can be performed by a small number of people in a short time.

[0046]

Since the pile joint according to the present invention has the above-described structure and operation, implementing the pile joint according to the present invention has the following great effects.

(1) In the present invention, since a ring-shaped reverse rotation preventing member is interposed between the male and female joints connected by a screw type, the male and female joints are reversely rotated by the action of the ring-shaped reverse rotation preventing member. Can be prevented from becoming loose. (2)
In the case where the reverse rotation preventing mechanism is provided as described in the preceding paragraph, and the male and female joints are pressed at two places, the final strength of the pile joint can be further increased.

(3) The ring-shaped reverse rotation preventing member used in the present invention may be a combination of two or a single member. (4) The installation of the ring-shaped reverse rotation prevention member does not require any work such as welding on site or installation of a rotation stopper, and can be performed in a short time by a small number of people.

[Brief description of the drawings]

FIGS. 1A and 1B are longitudinal sectional explanatory views showing the structure of a pile joint according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an example of a ring-shaped reverse rotation preventing member used in the first embodiment of FIG.

3 (A) and 3 (B) are longitudinal sectional explanatory views showing a structure of a pile joint according to a second embodiment of the present invention.

FIGS. 4A and 4B are longitudinal sectional explanatory views showing the structure of a pile joint according to a third embodiment of the present invention.

FIGS. 5A and 5B are longitudinal sectional explanatory views showing the structure of a pile joint according to a fourth embodiment of the present invention.

6 (A) and 6 (B) are longitudinal sectional explanatory views showing a structure of a pile joint according to a fifth embodiment of the present invention.

FIGS. 7A and 7B are longitudinal sectional explanatory views showing the structure of a pile joint according to a sixth embodiment of the present invention.

FIG. 8 is a graph showing a result of a torsion test of a screw type pile joint provided with the reverse rotation preventing mechanism according to the first embodiment of the present invention.

9 (A) is an explanatory view of the operation of the reverse rotation stopping mechanism, FIG.
(B) is a diagram showing the force relationship on the slope surface of the reverse rotation stopping mechanism.

[Explanation of symbols]

 1,2 pile body 3 male joint 4 female joint 5 steps 6 outer diameter base 7 screw section 8 steps 9 screw section 10 inner bottom section 11 V groove groove 12,13,14,15 Ring-shaped reverse rotation stopper 12a, 13a, 14a, 15a One side 12b, 13b, 14b, 15b One side 16,17,18,19 Ring-shaped anti-rotation member 16a, 17a, 18a, 19a One side 16b, 17b, 18b, 19b One side

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masaho Tanaka 1-5 Nakanoyo Terao, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture (72) Inventor Takeshi Iguchi 1064-16 Tamado, Shimodate-shi, Ibaraki Pref. In-company (72) Inventor Tsuyoshi Ikeda 1064-16 Tamado, Shimodate-shi, Ibaraki Pref.

Claims (5)

[Claims] In a joint capable of connecting ready-made piles to each other,
A pile joint characterized in that a male joint and a female joint are screw-connected to each other, and the male joint and the female joint are provided with a reverse rotation preventing mechanism. 2. When the male joint and the female joint are connected to each other, the distal end of the female joint and the outer diameter base of the male joint press against each other, and both the male joint distal end and the inner bottom of the female joint. The pile joint according to claim 1, wherein the pile joints are pressed against each other. 3. A ring-shaped anti-rotation member of a pair of ring-shaped anti-rotation members projecting at several places in the direction of tightening screws which can be meshed with each other. 3. The female joint according to claim 1, further comprising an inner bottom portion provided at an inner bottom portion of the female joint, and the other ring-shaped reverse rotation preventing member provided at an inner bottom portion of the female joint or a distal end portion of the male joint. Pile joints. 4. One of a pair of ring-shaped reverse rotation preventing members projecting at several places in the direction of tightening screws that can mesh with each other, the one ring-shaped reverse rotation preventing member is connected to the outer diameter of a male joint. 3. The method according to claim 1, wherein the base member or the distal end of the female joint is provided, and the other ring-shaped reverse rotation preventing member is provided at the distal end of the female joint or the outer diameter base of the male joint. Any pile joint. 5. A ring-shaped reverse rotation preventing member having a downward slope projecting at several places in the direction of screw tightening is attached to the distal end of the female joint, the inner bottom, or the outer diameter base or the distal end of the male joint, and the male joint is provided. 3. An uneven surface which can be meshed with an uneven surface of the ring-shaped reverse rotation preventing member at an outer diameter base portion or an end portion or an end portion or an inner bottom portion of a female joint. The pile joint according to claim 2.