JPH11325041A - Nut locking device for field structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily break an adhesive when a cap is removed by screwing the cap to the shaft end section of a bolt, and fixing the female screw section of the cap and the male screw section of the shaft end section with the adhesive. SOLUTION: The outer peripheral face of a cap 7 is formed into a smooth cylinder wall face 8, its top face 9 is formed into a smooth and nearly semispherical face, a blank female screw hole 10 opened downward is provided, and a female screw section 11 is formed on the female screw hole 10. When the cap 7 is screwed to the shaft end section 3a of a bolt 3, an adhesive 16 is applied to the female screw section 11 of the cap 7 and the male screw section of the bolt shaft end section 3a. The cap 7 coated with the adhesive 16 is fastened to the shaft end section 3a of the bolt 3 by a dedicated tool 13, and the female screw section 11 of the cap 7 and the male screw section of the shaft end section 3a can be firmly fixed and locked by the hardened adhesive 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for locking a nut in an outdoor structure such as a power transmission tower.

[0002]

2. Description of the Related Art Since a tower for a power transmission line has collapsed, a lock for preventing a person from maliciously loosening a bolt and a nut fastening a connecting portion of a structure in the tower. There is a need to provide equipment. Therefore, for example, a technique using an octagonal nut other than a normal hexagonal nut and a technique for fixing the nut to a bolt by spot welding have been proposed.

[0003]

According to the technique using an octagonal nut as described above, a conventional hexagonal wrench cannot be used, so that the object as a locking device can be achieved as long as it is used. However, even with an octagon nut,
As long as the outer periphery is a polygon, if it is strongly pinched and rotated by a monkey spanner or the like, it may be loosened, and it is difficult to fundamentally solve the problem.

[0004] Further, according to the technique of spot welding a nut to a bolt, it is possible to securely lock the nut. However, it is preferable to disperse the welding spark in a mountain field where a steel tower is constructed because of the danger of a wildfire. Absent. In addition, even in the case of a steel tower, it may be necessary to loosen the nut for repair or the like, and in this case, the work for peeling off the spot welding portion becomes extremely difficult.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention firstly sets a cap so that the nut does not come off from the bolt, rather than directly locking the nut itself so that it cannot rotate. It is advantageous to screw the bolt to the shaft end and indirectly lock the nut with such a cap. Second, the cap cannot be rotated even with a conventional general-purpose tool. Advantageously, it is advantageous that only authorized workers can rotate using a special tool. Thirdly, even if the user tries to rotate the cap after mounting with a strong force, It has been found that it is advantageous to use an adhesive so that it does not become loose, while allowing the authorized worker to easily break the adhesive when removing the cap.

In view of the above, the present invention is constructed as a means. In a field construction in which a connecting portion of a structure is fastened with a bolt and a nut and a shaft end of the bolt is inserted from the nut, a female screw portion is provided. The cap is screwed to the shaft end of the bolt, and the female thread of the cap and the male thread of the shaft end are fixed to each other with an adhesive capable of thermally destructing each other. The point is that it is formed on a substantially smooth cylindrical wall surface.

Preferably, the adhesive is a two-component adhesive, which easily penetrates into the gap between the female thread of the cap and the male thread of the shaft end, cures at room temperature, and has an adhesive force. Although it is strong, it is more preferable that the adhesive is of a type that can be easily broken when heated.

Further, in order to make the cap rotatable only by the special tool, recesses are formed at intervals in the circumferential direction of the outer peripheral surface of the cap, and the outer peripheral surface of the cap is held against this. It is preferable to use a special tool provided with an engaging portion that engages with the concave portion on the inner surface of the socket.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a part of a power transmission tower as an example of an outdoor structure.
A connecting portion is formed by the flanges 2, 2 which are abutted with each other, and are connected by a headed bolt 3 passing through the flanges 2, 2 and a nut 4 fastened to the bolt 3. The nut 4 usually constitutes a double nut, and the first nut 4
a and the second nut 4b, and the shaft end 3a of the bolt 3 is inserted through the second nut 4b. A washer 5 is interposed between the head 3b of the bolt 3 and the flange 2, and a washer 6 is interposed between the first nut 4a and the flange 2.

In the outdoor construction having such a configuration, in the present invention, the bolt 3
The cap 7 is attached to the shaft end 3a of the.

FIG. 2 shows a first embodiment of the present invention. As shown in FIGS. 2A, 2B and 2C, the cap 7 has a substantially smooth outer peripheral surface. Cylindrical wall 8
And the top surface 9 is formed into a smooth substantially hemispherical surface, and a blind female screw hole 10 that opens to the lower side is provided.
A female screw portion 11 is formed in the female screw hole 10. FIG.
As shown in (A) and (C), the cylindrical wall surface 8 forms recesses 12 at intervals in the circumferential direction.
Is so as not to impair the almost smooth surface of the cylindrical wall surface 8.
A thin groove extending in the axial direction of the cap 7 is formed. For this reason, the cylindrical wall surface 8 cannot engage a conventional general-purpose tool such as a spanner or a wrench, and can engage only the dedicated tool 13 as illustrated.

The special tool 13 has a socket 14 for holding the outer peripheral surface of the cap 7, and an engaging portion 15 for engaging with the recess 12 is formed on the inner surface of the socket 14. In the case of the example in the figure, the engaging portion 15 constitutes a rib fitted into the concave portion 12, and the socket 14 faces the top surface 9 of the cap 7 and the engaging portion 15 and the concave portion 12 are positioned. When the cap 7 is inserted into the socket 14, the engaging portion 15 is engaged while being fitted along the concave portion 12, and the cap 7 is connected to the socket 14 so as to rotate integrally with the socket 14. Therefore, by using such a special tool 13, the female screw portion 11 of the cap 7 can be fastened to the shaft end 3 a of the bolt 3.

Therefore, the cap 7 is connected to the shaft end 3 of the bolt 3.
At the time of screwing to the screw a, the adhesive 16 is applied to the female screw 11 of the cap 7 and the male screw of the bolt shaft end 3a. The adhesive 16 is preferably a two-component adhesive, and is an adhesive that can be broken by applying high-temperature heat after curing.

That is, when the cap 7 is fastened to the shaft end 3a of the bolt 3 with the special tool 13 in a state in which the adhesive 16 is applied, as shown in FIG. The adhesive 16 which has hardened the external thread portions of the end 3a is firmly fixed to each other to enable locking. For this reason,
Thereafter, even if someone tries to loosen and remove the cap 7 with a general-purpose tool, the cap 7 cannot rotate and does not loosen.

As the adhesive 16, for example, a two-component epoxy-polyamide adhesive can be used. According to this two-component epoxy-polyamide adhesive,
Because it cures at room temperature, it can be used safely in Yamano, and
Since it is easy to fill the gap in the two-liquid mixed state, it easily penetrates into the above-mentioned screw portion, and furthermore, since there is little shrinkage after curing, strong adhesion is possible. On the other hand, when heated at a high temperature due to low heat resistance, thermal destruction is easy, and when it is necessary for an authorized worker to loosen the nut 4 for repair or the like, high-temperature heat is applied to the cap 7. And the adhesive 16 are broken, so that the cap 7 is
Can be easily removed. In addition, a two-component polyurethane adhesive, a two-component acrylic adhesive, a two-component polysulfide adhesive, or the like can be used.

As shown in FIG. 2D, the adhesive 16
It is preferable to apply a sufficient amount so as to substantially fill the female screw hole 10 of the cap 7, penetrate into the gap between the mutually threaded threads of the cap 7 and the shaft end 3 a, and It also penetrates between the press contact surfaces of the nut 4 and enables strong bonding. Alternatively, although not shown, a capsule in which a two-part mixed type adhesive is sealed is inserted into the female screw hole 1 of the cap 7.
0, and the shaft end 3a may be screwed into the female screw hole 10 to break the capsule and mix the two liquids.

As described above, when the authorized worker loosens the nut 4 for repair or the like, high-temperature heat is applied to the cap 7 to facilitate the work of breaking the adhesive 16, as shown in FIG. As shown in FIG. 1A, a heater 17 such as a hot wire is built in a socket 14 of
An ON / OFF switch may be provided in a power supply for operating the power supply 7. According to this, the worker can heat the cap 7 and break the adhesive 16 by heat only by fitting the socket 14 of the special tool 13 to the cap 7 outside. , The cap 7 can be removed from the shaft end 3a as it is, and the working efficiency is good.

[Second Embodiment] FIG. 3 shows a first embodiment of the present invention. The cap 7 has an outer peripheral surface formed on a substantially smooth cylindrical wall surface 8 and a top wall 9a formed on a flat surface. The nut 18 is fixed to the inner surface of the top wall 9a by welding or the like. The cylindrical wall surface 8 of the cap 7 is formed so as to completely surround not only the shaft end 3a of the bolt 3 exposed from the flange 2 but also the nut 4 (the first nut 4a and the second nut 4b) and the washer 5. ing. The nut 18 has a female screw hole 10 provided with a female screw portion 11 so as to be screwed to the shaft end 3 a of the bolt 3. The cylindrical wall 8 has recesses 12 formed at intervals in the circumferential direction. The recess 12 has a thin groove extending in the axial direction of the cap 7 so as not to impair the substantially smooth surface of the cylindrical wall 8. Constitute. For this reason, the cylindrical wall surface 8 cannot engage a conventional general-purpose tool such as a wrench or a wrench, and can engage only the special tool 13 as described above.

The special tool 13 has the same configuration as that described in the first embodiment, and has a rib-like engaging portion formed on the inner surface of the socket holding the outer peripheral surface of the cap 7. The cap 7 can be driven to rotate by engaging the engaging portion with the concave portion 12 of the cap 7.

When screwing the nut 18 of the cap 7 to the shaft end 3a of the bolt 3, the female thread 1
1 and the external thread of the bolt shaft end 3a.
Is applied. The adhesive 16 is preferably a two-component adhesive similar to that described in the first embodiment. After curing, the adhesive 16 can be broken by applying high-temperature heat. The parts 3a are firmly fixed to each other.

Therefore, with the cap 7 attached,
Even if someone loosens the cap 7 with a general-purpose tool and tries to remove it, the cap 7 cannot rotate and does not loosen. In addition, since the nut 4 is covered with the cap 7, a general-purpose tool such as a spanner cannot be engaged with the nut 4. On the other hand, when the authorized worker loosens the nut 4 for repair or the like, if the high temperature heat is applied to the cap 7, the adhesive 16 is destroyed. It can be removed from the end 3a. At this time, as described above, the use of a dedicated tool having a built-in heater can improve work efficiency.

[0023]

According to the present invention, the nut 7 is not directly locked so that it cannot be rotated, but the cap 7 is fixed to the shaft end 3 so that the nut 4 does not come off from the bolt 3.
a, and the nut 4 is indirectly locked by such a cap 7, so that there is no problem that the lock state is incomplete as in the conventional octagonal nut.
In addition, there is no problem of causing danger or making the intended removal work difficult unlike conventional spot welding, and the desired purpose can be suitably achieved.

According to the present invention, a concave portion 12 is formed on the outer peripheral surface of the cap 7 so as to form a substantially smooth cylindrical wall surface 8 while engaging only the engaging portion 15 of the socket 14 of the special tool 13. With this configuration, it is impossible to rotate the cap 7 using a conventional general-purpose tool,
This is advantageous in that it is possible to reliably prevent someone from loosening the nut 4 by malicious intent.

Further, in addition to such a configuration, according to the present invention, when the cap 7 is screwed onto the shaft end 3a of the bolt, the female thread 11 of the cap 7 and the male thread of the bolt shaft end 3a are connected. Since the structure is fixed by the adhesive 16 which can be thermally destroyed with each other, there is no fear that the cap 7 after being mounted will be loosened even if the cap 7 is rotated with a strong force by a general-purpose tool, and the cap 7 is securely locked. On the other hand, when the authorized operator removes the cap, the adhesive is destroyed by heating the cap 7 and then the special tool 1 is removed.
3, the cap 7 can be easily removed.
This has the effect of being able to suitably respond to repairs and other needs.

[Brief description of the drawings]

FIG. 1 is an external view showing an example of an outdoor construction in which the present invention is implemented.

2A and 2B show a first embodiment of the present invention, wherein FIG. 2A is a perspective view showing a cap and a special tool, FIG. 2B is a longitudinal sectional view of the cap, FIG. D) is a longitudinal sectional view showing a state where the cap is attached to the end of the bolt shaft.

3A and 3B show a second embodiment of the present invention, wherein FIG. 3A is a longitudinal sectional view of a cap, FIG.
(C) is a longitudinal sectional view showing a state where the cap is attached to the end of the bolt shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Structure 3 Bolt 3a Shaft end part 4a First nut 4b Second nut 7 Cap 8 Cylindrical wall surface 10 Female screw hole 11 Female screw part 12 Concave part 13 Special tool 14 Socket 15 Engaging part 16 Adhesive 17 Heater

Claims (3)

[Claims] 1. An outdoor construction in which a connecting portion of a structure is fastened with a bolt and a nut and a shaft end of the bolt is inserted from the nut, wherein a cap having a female screw portion is attached to the shaft end of the bolt. At the same time, the female screw portion of the cap and the male screw portion of the shaft end are fixed to each other with an adhesive capable of thermally destructing each other, and the cap has an outer peripheral surface formed on a substantially smooth cylindrical wall surface. A locking device for a nut in an outdoor structure, characterized in that the device is characterized in that: 2. The lock device according to claim 1, wherein the adhesive comprises a two-component adhesive. 3. The cap is formed by forming recesses at intervals in a circumferential direction of an outer peripheral surface, and a tool for rotating the cap with respect to a shaft end of a bolt holds the outer peripheral surface of the cap. The locking device for a nut in an outdoor construction according to claim 1 or 2, further comprising an engaging portion that engages with the concave portion on an inner surface of a socket to be held.