JP3054377U - Bolt and nut removal prevention bracket - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent bolts and nuts used in a steel tower or a bridge from being removed with a normal rotating tool. SOLUTION: An inner ring 2 is non-rotatably fixed to a bolt head 4A, a nut or the like, and a cover 3 is rotatably fitted to the inner ring 2 so as to be unable to be pulled out in the axial direction.
It is composed of

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 This invention relates to bolts and nuts used for steel towers, bridges, other structures, and automobile wheels.

[0002]

[Prior art]

 In general, bolts and nuts are used to assemble towers, bridges, and other structures, and to attach automobile wheels. Conventionally, bolts and nuts of this type can be mounted and removed by any number of people using a commercially available rotating tool such as a spanner.

[0003]

[Problems to be solved by the invention]

 By the way, the current situation is that the wheels are not easily removed by the rotating tool, so that the wheels are not stolen, and the fixing bolts and nuts at the lower end of the tower have recently A serious accident has occurred in which a tower was overturned after being removed by a mindless person. The present invention has been made in view of the above situation, and its purpose is to provide a bolt for preventing bolts and nuts used in a steel tower or a bridge from being removed with a normal rotating tool. To offer.

[0004]

[Means for Solving the Problems]

 In the present invention, the following technical measures were taken to achieve the above object. That is, the present invention comprises an inner ring which is non-rotatably fitted to the bolt head / nut, and a cover which is rotatably fitted to the inner ring so that it cannot be pulled out in the axial direction. It is characterized by: In this case, if the inner ring is forcibly fitted to the fixed bolt head or the nut, the inner ring cannot be removed together with the cover. Therefore, even when the cover is rotated, the inner ring does not rotate, so that the bolt / nut does not rotate, and thus the bolt or nut cannot be removed.

Further, the present invention is characterized in that a special screw hole is provided in the center of the outer end wall of the cover in the axial direction of the bolt and nut. In this case, if a push bolt of the same special screw is screwed into the screw hole, the tip of the push bolt comes into contact with the fixing bolt head or the fixing bolt tip, so that the cover is not rotated by a pipe wrench or the like, Further, when the push bolt is forcibly screwed in, the cover moves in the direction of withdrawing the bolt in the axial direction, and together with the cover, the inner ring comes off from the fixing bolt head or nut. In this way, by removing the inner ring together with the cover, the fixing bolt / nut can be removed.

The present invention is characterized in that the inner ring is provided with a slit in the axial direction. In this case, when the inner ring is forcibly fitted to the fixing bolt head or the nut, the inner ring spreads slightly, so that it becomes very easy to fit.When removing the inner ring together with the cover using the push bolt, The inner ring spreads slightly, making it easier to pull out.

Further, according to the present invention, a peripheral groove is provided on the outer peripheral surface of the ring, and one or a plurality of pin holes are provided in the cover in a corresponding manner to the peripheral groove so as to penetrate therethrough. The retaining pin may be driven so as to fit into the peripheral groove. In this case, the structure for preventing the cover from coming off with respect to the ring can be made reliable and strong.

Further, the present invention can be configured such that a bolt shaft end receiving portion is provided at an outer end in the bolt axis direction of the cover. In this case, it is most suitable to cover the inner ring on a fixing nut screwed into a fixing bolt. The bolt shaft end receiving portion may be the same as the inner diameter of the inner ring receiving portion of the cover, or may be reduced in diameter.

[0009]

[Embodiment of the invention]

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 and 2 show a first embodiment of a bolt / nut removal prevention bracket according to the present invention. The metal fitting 1 is composed of an inner ring 2 which is externally fitted and fixed to a fixing bolt head 4A (or a nut), and a cover 3 which is rotatable on the ring 2 and externally fitted so as not to be pulled out in the axial direction. I have.

[0010] As shown in the drawing, the ring 2 has a cylindrical outer peripheral surface 2A, a hexagonal hole 2B inside which is the same as the hexagonal columnar surface of the head 4A of the fixing bolt 4, and an inwardly outward end in the axial direction. A flange 2C is formed, and a notch 5 for retaining is provided on the outer peripheral surface of the opposite end of the flange 2C over the entire circumference.

As shown in FIG. 2, the cover 3 has a cylindrical shape with a cover, and an axially outer end wall 6 is provided with a concentric special screw hole 7 at the center thereof. The diameter of 3A is slightly (0, 5 to 1 mm) larger than the diameter of the outer peripheral surface 2A of the ring 2 and is rotatable with respect to the inner ring 2. After the ring 2 is inserted into the cover 3, the inner peripheral side of the cover 3 opposite to the wall 6 is caulked toward the center side and locked to the notch 5 of the ring 2 so as to be relatively rotatable. A retaining portion 8 is formed.

In the first embodiment, when the metal fitting 1 is fixed to the head 4A of the fixing bolt 4 assembling the structural material 9 of the structure, the bolt head 4A is aligned with the hexagonal hole 2B of the inner ring 2. Then, the inner ring 2 is forcibly fitted to the bolt head 4A by hitting the outer end wall 6 of the cover 3 with a hammer or the like. At this time, the end face of the inner ring 2 hits the surface of the component 9, but a slight gap is formed between the end surface of the cover 3 and the retaining portion 8 and the component 9, and the cover 3 becomes rotatable. .

In a state where the metal fitting 1 is externally fitted to the head 4A of the fixing bolt 4, the cover 3 is simply rotated, and even if a rotating tool such as a spanner or a pipe wrench is used, it is no longer removed from the bolt head 4A. Cannot be removed. Therefore, it is possible to prevent the fixing bolts 4 such as a steel tower from being removed by a person other than a specific person concerned, especially a person with no mind.

Therefore, as shown by a two-dot chain line in FIG. 1, a specific person, such as a manager of a steel tower, stores a push bolt 10 that can be screwed into the special screw hole 7, and When it is necessary to remove the cover 3, the push bolt 10 is screwed into the special screw hole 7 of the cover 3, and the cover 3 is held by a pipe wrench or the like so as not to rotate. When the push bolt 10 is further screwed in even when the cover 4 hits the head 4A, the cover 3 moves together with the inner ring 2 in the direction indicated by the arrow A in FIG.

[0015] In the first embodiment, it is possible to prevent the bolt head 4A from being detached by being fitted to the fixing nut outside the bolt head 4A. 3 and 4 show a second embodiment of the present invention. Unlike the first embodiment, a retaining means for the inner ring 2 of the cover 3 is formed on the outer peripheral surface 2A of the ring. A peripheral groove 11, a retaining pin 13 driven into three pin holes 12 provided in the cover 3 corresponding to the peripheral groove 11, and an axial line with the inner ring 2. The point is that a slit 14 extending in the direction is provided.

The pin 13 has an inner end slidably fitted in the peripheral groove 11 and an outer end flush with the outer peripheral surface of the cover 3 so that the pin 13 cannot be pulled out of the cover 3. In the second embodiment, the structure of the retaining means is simple, reliable and strong, and it is easy to externally fix the inner ring 2 to the fixing bolt head 4A or its nut. Although it is easy to remove the metal fitting 1 by using this method, the same operation and effect as those of the first embodiment can be expected in other respects. Therefore, the same components are denoted by the same reference numerals as in FIGS. 1 and 2, and detailed description is omitted.

FIGS. 5 to 7 show a third embodiment of the present invention. The difference from the second embodiment is that the inner ring 2 has a shape without the inward flange 2 C (see FIGS. 6 and 7). A special screw hole 7 is provided in the outer end wall 6 of the cover 3 by extending a housing portion 15 of the bolt shaft end portion 4B from a center portion thereof and providing a special screw hole 7 in the center of the outer wall 16 of the housing portion 15. It is the most suitable as the removal prevention metal fitting 17 of 17 and has the same operation and effect as the second embodiment. Therefore, the same components as those of the second embodiment are denoted by the same reference numerals as in FIGS. 4 and 5, and the detailed description is omitted.

The accommodation portion 15 of the bolt shaft end 4 B is formed by reducing the diameter of the outer end of the cover 3, but can be configured without reducing the diameter of the cover 3. In each of the above embodiments, the outer shape of the cover 3 is cylindrical, but may be square, hexagonal, octagonal, polygonal, or a shape having two parallel surfaces. Further, in the first embodiment, the slit 14 can be provided in the inner ring 2, and the shape of the inner ring 2 can be the one shown in FIGS.

Further, the shape of the hole 2B of the inner ring 2 is not limited to a hexagon, but may be a shape shown in FIG. 8 or a shape that can be fitted to a bolt head or a nut to make it impossible to rotate relatively. If there is no need to remove the fixing nut of the structure, it is obvious that the special screw hole 7 is not provided. When the metal fittings 1 and 21 are removed from the bolt head or the nut, the pins 13 can be driven more strongly to fix the cover 3 so as not to rotate with respect to the inner ring 2.

The present invention is not limited to the above embodiments. For example, in the first embodiment, the retaining ring 8 is screwed or pinned on the end face of the cover without caulking the retaining means 8 of the cover 3. The design can be changed as appropriate, and it can be attached to the wheel mounting bolts / nuts of the automobile.

[0021]

[Effect of the invention]

 As described above, the present invention includes an inner ring fixed to the bolt head / nut so as to be non-rotatably fitted to the outside, and a cover rotatably fitted to the inner ring so as not to be pulled out in the axial direction. The bolts and nuts used in structures such as towers cannot be removed with ordinary rotating tools, and therefore the bolts and nuts cannot be Removal can be completely prevented and accidents can be avoided.

By providing a special screw hole at the center of the outer end wall of the cover in the axial direction of the bolt and nut, only a specific person can remove the fixing bolt and nut using a push bolt. Also, by providing the inner ring with a slit in the axial direction, the inner ring can be easily fitted to the bolt head or the nut, and the metal fitting can be easily removed from the fixing bolt / nut using the push bolt. Can be

[Brief description of the drawings]

FIG. 1 is a central longitudinal sectional view showing a first embodiment of the present invention.

FIG. 2 is a bottom view of FIG.

FIG. 3 is a central longitudinal section showing a second embodiment of the present invention (FIG. 4);
(A-A line cross section) of FIG.

FIG. 4 is a sectional view taken along line BB of FIG. 3;

FIG. 5 is a central longitudinal sectional view showing a third embodiment of the present invention.

FIG. 6 is a front view of an inner ring according to a third embodiment.

FIG. 7 is a sectional view taken along line CC of FIG. 6;

FIG. 8 is a plan view showing a modification of the inner ring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bolt / nut removal prevention metal fitting 2 Inner ring 2A Outer peripheral surface 3 Cover 4 Fixing bolt 4A Bolt head 4B Bolt shaft end 6 Cover outer end wall 7 Special screw hole 11 Peripheral groove 12 Pin hole 13 Driving pin 14 Slit 15 Outside bolt End housing 16 Outer end wall of housing 17 Nut 21 Nut removal prevention fitting.

Claims (5)

[Utility model registration claims] 1. An inner ring fixed to a bolt head / nut so as to be non-rotatably fitted to an outer ring, and a cover rotatably fitted to the inner ring so as not to be pulled out in the axial direction. A bolt and nut removal prevention bracket characterized by the following characteristics. 2. The bolt / nut removal prevention bracket according to claim 1, wherein a special screw hole is provided at a center of an outer end wall of the cover in the axial direction of the bolt / nut. 3. The bolt / nut removal prevention bracket according to claim 1, wherein the inner ring is provided with a slit in the axial direction. 4. A peripheral groove is provided on an outer peripheral surface of the ring,
One or a plurality of pin holes are provided in the cover corresponding to the peripheral groove in a penetrating manner, and a retaining pin is driven into the pin hole so as to fit in the peripheral groove. The metal fitting for preventing removal of a bolt or a nut according to claim 1, 2 or 3. 5. The bolt / nut removal prevention bracket according to claim 1, wherein a bolt shaft end receiving portion is provided at an outer end of the cover in the bolt axis direction. .