JP2021032389A - Fall prevention tool - Google Patents

Abstract

To provide a fall prevention tool which is easily attachable to a bolt.SOLUTION: A fall prevention tool 1 comprises a first coil spring part 2, a second coil spring part 3, a first arm part 4 and a second arm part 5. The first coil spring part 2 has a wound first coil strand 2A, and the second coil spring part 3 has a second coil strand 3A which is wound with a first center axial line 7 as a center. A center angle 12 between a first line 9 for connecting one end of the second coil strand 3A and the first center axial line 7, and a second line 10 for connecting the other end of the second coil strand 3A and the first center axial line 7 is 110°. A first connection point 13 between one end of the second coil strand 3A and a third coil strand 4A, and a second connection point 14 between the other end of the second coil strand 3A and a fourth coil strand 5A intersect with a virtual substantially-circular body 6 having a radius larger than a winding radius of the second coil spring part 3 with a second center axial line 8 extending in substantially-parallel with the first center axial line 7 as a center.SELECTED DRAWING: Figure 2

Description

The present invention relates to a fall-prevention device. More specifically, the present invention relates to a fall-off preventive tool that prevents a fixed object or a nut from falling off from a bolt.

Generally, as a method for fixing two members constituting a building structure, a method of fixing by welding and a method of fastening with bolts and nuts are used.

In addition, fixing by welding requires welding equipment, which takes time and effort to construct, and equipment is also required to release the fixing, which takes time and effort to release the fixing. Therefore, fasten with bolts and nuts. Many methods have been adopted.

However, in the method of fastening with bolts and nuts, the bolts and nuts may loosen after fastening due to vibrations, etc., so the bolts and nuts loosen and the objects to be fixed and nuts fall off from the bolts. Several inventions have been proposed to prevent this.

For example, Patent Document 1 describes a loosening stopper 100 as shown in FIG. 5 (b).
That is, the loosening stopper 100 prevents the nut 102 screwed into the bolt 101 from loosening.

Further, the loosening stopper 100 includes a coil spring 104 shown in FIG. 5 (a) and a ring material 106 shown in FIG. 5 (b).
Further, the coil spring 104 is slightly smaller than the outer diameter of the bolt 101, and is formed in a spiral ring shape with an inner diameter that can be locked in the screw groove while expanding in the radial direction by elastically deforming.

Further, the tip portion 105 of the wire 107 of the coil spring 104 is obliquely processed as shown in FIG. 5 (b). As a result, the tip 105 is screwed into the gap between the bolt 101 and the nut 102, so that the tip 105 acts as a stopper and the nut 102 cannot rotate in the return direction.

Further, as shown in FIG. 5B, the ring material 106 has an outer surface in which the diameter of the surface opposite to the upper surface, that is, the surface facing the nut 102, and the diameter of the lower surface, that is, the surface facing the nut 102 are different from each other. Is formed in an inclined cylindrical shape.

Further, the inner diameter of the ring material 106 is substantially the same as the outer diameter of the coil spring 104 mounted in the screw groove of the bolt 101.
Further, as shown in FIG. 5B, by attaching the ring material 106 so as to cover the outer periphery of the coil spring 104 mounted in the screw groove, the loosening stopper 100 can be more reliably mounted.

Utility Model Registration No. 3128915

By the way, although the loosening stopper described in Patent Document 1 can be reliably attached to the screw groove, no device has been devised to facilitate the attachment to the screw groove.
Therefore, when the loosening stopper described in Patent Document 1 must be quickly attached to the screw groove of the bolt, there is a possibility that the attachment of the loosening stopper may be delayed.

The present invention has been devised in view of the above points, and an object of the present invention is to provide a fall-off preventive device that can be easily attached to a bolt.

In order to achieve the above object, the fall prevention tool of the present invention has a first coil wire having a winding radius of a predetermined size and including a portion wound in a polygonal shape. The coil spring portion of the first coil spring portion extends in a direction substantially orthogonal to the winding radial direction of the first coil spring portion, and has a substantially circular shape centered on the central axis passing through the winding center of the first coil spring portion. The first coil wire having substantially the same diameter and wound with a winding radius smaller than the winding radius of the first coil spring portion and in the direction in which the central axis extends. A second coil spring portion arranged at a position different from the position of the coil spring portion of the above, and one end connected to one end of the first coil wire of the first coil spring portion, and opposite to one end. A first coil wire having a third coil wire that is connected to one end of the second coil wire of the second coil spring portion and that protrudes in a direction away from the central axis. The arm portion is connected to the other end of the second coil wire of the second coil spring portion, which is opposite to one end connected to the third coil wire, and from the central axis. A first wire having a second arm portion having a fourth coil wire protruding in a distant direction and connecting the one end of the wound second coil wire with the central axis. The angle between the other end of the wound second coil wire and the second wire connecting the center axis is 90 ° or more and 180 ° or less when viewed in the direction in which the center axis extends. The first connection point, which is the connection point between the one end of the second coil wire and the third coil wire, the other end of the second coil wire, and the fourth coil wire. The second connection points, which are the connection points with the coil wires of the above, are curved.

Here, even if the nut tries to rotate in the loosening direction by the first coil spring portion having a winding radius of a predetermined size and having a first coil wire including a portion wound in a polygonal shape. Since it hits the first coil spring portion and is hard to move any more, it is possible to prevent the nut from rotating in the loosening direction.

The "predetermined size" referred to in the present invention is, for example, a size that can come into contact with the side surface of the nut.
The winding radius of the first coil spring portion means the radius of the circumscribed circle of the polygon.

Further, the first coil spring portion extends in a direction substantially orthogonal to the winding radius direction of the first coil spring portion, and is centered on the central axis passing through the winding center of the first coil spring portion, and has substantially the same diameter in a substantially circular shape. Moreover, it has a second coil wire wound with a winding radius smaller than the winding radius of the first coil spring portion, and is different from the position of the first coil spring portion in the direction in which the central axis extends. A second coil spring portion located at the position allows fitting into a thread groove formed in the leg portion of the bolt.

Further, one end is connected to one end of the first coil wire of the first coil spring portion, and the other end opposite to one end is connected to one end of the second coil wire of the second coil spring portion. A third coil element of a first arm portion and a second coil element wire of the second coil spring portion, which are connected and have a third coil element wire protruding in a direction away from the central axis. A first arm portion is provided by a second arm portion which is connected to the other end on the opposite side to the other end connected to the wire and has a fourth coil wire protruding in a direction away from the central axis. The diameter of the second coil spring portion can be expanded by pressing the second arm portion with two fingers, for example, and moving the first arm portion and the second arm portion in a direction in which they approach each other.

Further, a first wire connecting one end of the wound second coil wire and the central axis, and a second wire connecting the other end of the wound second coil wire and the central axis When the angle between the two is 90 ° or more and 180 ° or less when viewed in the direction in which the central axis extends, the first connection point and the second connection point are more than when the angle is less than 90 °. Since it exists at a position away from the winding center of the second coil spring portion, when the first arm portion and the second arm portion are brought close to each other in order to expand the diameter of the second coil spring portion, the first arm portion and the second arm portion are brought close to each other. It is difficult for the 1st connection point and the 2nd connection point to enter the inside of the 2nd coil spring portion.

Further, since the first connection point and the second connection point are curved respectively, the diameter of the second coil spring portion is made a perfect circle while the diameter is expanded to an ellipse in the configuration where the connection point is a straight line. The diameter can be increased, and the leg portion of the bolt can be easily inserted into the second coil spring portion.

Further, in the fall prevention tool of the present invention, the protruding length of the first arm portion and the protruding length of the second arm portion can be substantially the same as each other.

In this case, it is easier to push the arm portion by sandwiching it between two fingers than in a configuration in which the protruding length of the first arm portion and the protruding length of the second arm portion are different from each other.

Further, in the fall prevention tool of the present invention, the first coil wire of the first coil spring portion can be wound in a substantially hexagonal shape.

In this case, since the first coil spring portion corresponds to the shape of the nut, the first coil spring portion easily hits the side surface of the nut, and it becomes easier to further suppress the nut from rotating in the loosening direction.

Further, in the fall prevention tool of the present invention, the protruding tip of the first arm portion and the protruding tip of the second arm portion are curved, respectively, and the curvature of the protruding tip of the second arm portion is higher. The configuration may be larger than the curvature of the protruding tip of the first arm portion.

In this case, both ends of the third coil wire constituting the first arm portion are connected to the first coil wire of the first coil spring portion and the second coil wire of the second coil spring portion, respectively. Therefore, the first arm portion does not move when the diameter of the second coil spring portion is expanded, and the force for pushing the moving second arm portion can be made smaller than the force for pushing the first arm portion. As a result, it is possible to suppress the settling of the coil wire due to excessive pushing of the second arm portion.

Further, in order to achieve the above object, the fall prevention tool of the present invention has a first coil wire having a winding radius of a predetermined size and including a portion wound in a polygonal shape. The first coil spring portion and the first coil spring portion extend in a direction substantially orthogonal to the winding radial direction of the first coil spring portion, and are centered on a first central axis passing through the winding center of the first coil spring portion. It has a second coil wire that has substantially the same diameter in a substantially circular shape and is wound with a winding radius smaller than the winding radius of the first coil spring portion, and has a first center of the same. A second coil spring portion arranged at a position different from the position of the first coil spring portion in the direction in which the axis extends is connected, and one end thereof is connected to one end of the first coil wire of the first coil spring portion. The other end opposite to one end is connected to one end of the second coil wire of the second coil spring portion, and the other end projects in a direction away from the first central axis. The first arm portion having the third coil wire and the other end of the second coil wire of the second coil spring portion opposite to one end connected to the third coil wire. A second arm portion which is connected and has a fourth coil wire protruding in a direction away from the first central axis is provided, and one end of the second coil wire and the first coil wire are provided. The first connection point, which is the connection point with the coil wire of 3, and the second connection point, which is the connection point between the other end of the second coil wire and the fourth coil wire, are the above. A second coil spring that intersects a virtual substantially circular body having a radius larger than the winding radius of the second coil spring portion about a second central axis extending substantially parallel to the first central axis. The connection point between the one end of the coil wire and the third coil wire and the connection point between the other end of the second coil wire and the fourth coil wire are curved.

Here, even if the nut tries to rotate in the loosening direction by the first coil spring portion having a winding radius of a predetermined size and having a first coil wire including a portion wound in a polygonal shape. Since it hits the first coil spring portion and is hard to move any more, it is possible to prevent the nut from rotating in the loosening direction.

Further, it extends in a direction substantially orthogonal to the winding radius direction of the first coil spring portion and is substantially identical to a substantially circular shape centered on the first central axis passing through the winding center of the first coil spring portion. A first coil spring having a second coil wire that has a diameter and is wound with a winding radius smaller than the winding radius of the first coil spring portion, and in a direction in which the first central axis extends. The second coil spring portion, which is arranged at a position different from the position of the portion, can be fitted into the screw groove formed in the leg portion of the bolt.

Further, one end is connected to one end of the first coil wire of the first coil spring portion, and the other end opposite to one end is connected to one end of the second coil wire of the second coil spring portion. A third of the first arm portion and the second coil strand of the second coil spring portion, which are connected and have a third coil wire protruding in a direction away from the first central axis. By a second arm portion which is connected to the other end on the opposite side to the other end connected to the coil wire of the above and has a fourth coil wire protruding in a direction away from the first central axis. , The first arm part and the second arm part are sandwiched and pushed by, for example, two fingers, and the first arm part and the second arm part are moved in a direction approaching each other to expand the diameter of the second coil spring part. can do.

Further, the first connection point, which is the connection point between the one end of the second coil wire and the third coil wire, the other end of the second coil wire, and the fourth coil wire. A virtual second connection point having a radius larger than the winding radius of the second coil spring portion about the second central axis extending substantially parallel to the first central axis. When the first arm portion and the second arm portion are brought close to each other in order to expand the diameter of the second coil spring portion by intersecting with the substantially circular body of, one end of the second coil wire and the first The second connection point, which is the connection point between the first coil wire and the other end of the second coil wire and the fourth coil wire, is the second coil spring portion. It is difficult to get inside.

Further, since the first connection point and the second connection point are curved respectively, the diameter of the second coil spring portion is made a perfect circle while the diameter is expanded to an ellipse in the configuration where the connection point is a straight line. The diameter can be increased, and the leg portion of the bolt can be easily inserted into the second coil spring portion.

The fall-off preventive tool according to the present invention is easy to attach to a bolt.

It is the schematic perspective view which shows the dropout prevention tool of the 1st example to which this invention was applied. It is a schematic plan view which shows the dropout prevention tool of the 1st example to which this invention is applied. It is the schematic which shows the state when the fall prevention tool of the 1st example to which this invention was applied was attached to a bolt and a nut. It is a schematic plan view which shows the dropout prevention tool of the 2nd example to which this invention is applied. It is the schematic (a) which shows the coil spring which comprises the conventional loosening stopper, and the schematic (b) which shows the state when the conventional loosening stopper is attached to a bolt.

Hereinafter, embodiments of the present invention will be described with reference to the drawings for the purpose of understanding the present invention.
FIG. 1 is a schematic perspective view showing a dropout prevention device of a first example to which the present invention is applied.
Further, FIG. 2 is a schematic plan view showing a dropout prevention device of the first example to which the present invention is applied.
Further, FIG. 3 is a schematic view showing a state when the fall prevention tool of the first example to which the present invention is applied is attached to the bolt and the nut.

The fall prevention tool 1 of the first example of the present invention shown in FIG. 1 includes a first coil spring portion 2.
Here, the first coil spring portion 2 has a first coil wire 2A.
Further, the first coil wire 2A includes a portion wound in a substantially hexagonal shape with a winding radius having a predetermined size, for example, a size capable of contacting the side surface of the nut 16.

That is, the shape of the first coil spring portion 2 in the plane extending in the same direction as the winding radial direction of the first coil spring portion 2 is substantially hexagonal, and the first coil spring portion 2 has six tops 2B.

Further, the fall prevention tool 1 of the present invention includes a second coil spring portion 3.
Here, the second coil spring portion 3 has a second coil wire 3A.

Further, the second coil wire 3A extends in a direction substantially orthogonal to the winding radial direction of the first coil spring portion 2 and passes through the winding center of the first coil spring portion 2 with respect to the first central axis 7 It is wound around the center, in a substantially circular shape, having substantially the same diameter, and with a winding radius smaller than the winding radius of the first coil spring portion 2.

That is, the shape of the second coil spring portion 3 in the plane extending in the same direction as the winding radial direction of the second coil spring portion 3 is substantially circular.
Further, the inner diameter of the second coil spring portion 3 is slightly smaller than the outer diameter of the leg portion 15B of the bolt 15. This is to generate austerity force.

Further, the second coil spring portion 3 is arranged at a position different from the position of the first coil spring portion 2 in the direction in which the first central axis 7 extends.

Further, the fall prevention tool 1 of the present invention includes a first arm portion 4.
Here, the first arm portion 4 has a third coil wire 4A.

Further, one end of the third coil wire 4A is connected to one end of the first coil wire 2A of the first coil spring portion 2, and the side of the third coil wire 4A opposite to one end. The other end of the second coil spring portion 3 is connected to one end of the second coil wire 3A of the second coil spring portion 3, and the third coil wire 4A projects in a direction away from the first central axis 7.

Further, as shown in FIG. 1, the protruding tip 4B of the first arm portion 4 is curved.

Further, the fall prevention tool 1 of the present invention includes a second arm portion 5.
Here, the second arm portion 5 has a fourth coil wire 5A.

Further, the fourth coil wire 5A is connected to the other end of the second coil wire 3A of the second coil spring portion 3 opposite to one end connected to the third coil wire 4A. Moreover, it protrudes in a direction away from the first central axis 7.

Further, as shown in FIG. 1, the protruding tip 5B of the second arm portion 5 is curved.

Further, the curvature of the protruding tip 5B of the second arm portion 5 is larger than the curvature of the protruding tip 4B of the first arm portion 4.
That is, the protruding tip 4B of the first arm portion 4 is curved more gently than the protruding tip 5B of the second arm portion 5.

Further, the first wire 9 connecting one end of the wound second coil wire 3A and the first central axis 7 and the other end of the wound second coil wire 3A and the first one. The central angle 12 which is the angle between the second line 10 connecting the central axis 7 and the second line 10 when viewed in the direction in which the first central axis 7 extends is 90 ° or more and 180 ° or less.
In the example shown in FIG. 2, the central angle 12 is 110 °.

Further, the first connection point 13 which is the connection point between one end of the second coil wire 3A and the third coil wire 4A, and the other end of the second coil wire 3A and the fourth coil wire 4A. The second connection points 14 which are the connection points with the 5A are curved.

Further, the protruding length of the first arm portion 4 and the protruding length of the second arm portion 5 are substantially the same as each other.
That is, the length from the first connection point 13 to the protruding tip 4B of the first arm portion 4 and the length from the second connection point 14 to the protruding tip 5B of the second arm portion 5 are substantially the same. is there.

Further, in FIG. 2, a virtual substantially circular body 6 having a radius larger than the winding radius of the second coil spring portion 3 about the second central axis 8 extending substantially parallel to the first central axis 7 It is shown.
Here, since the central angle 12 is 90 ° or more and 180 ° or less, the first connection point 13 and the second connection point 14 intersect with the virtual substantially circular body 6.
That is, the first connection portion 13 and the second connection portion 14 are located at positions farther from the winding center of the second coil spring portion 3 than the position of the second coil wire 3A of the second coil spring portion 3. Existing.

Further, the first central axis 7 and the second central axis 8 are virtual straight lines having no substance.

In the fall prevention tool of the present invention, the protruding length of the first arm portion and the protruding length of the second arm portion do not necessarily have to be substantially the same as each other, for example, the protruding length of the first arm portion. May be longer than the protruding length of the second arm portion, or the protruding length of the first arm portion may be shorter than the protruding length of the second arm portion.

However, if the protruding length of the first arm portion and the protruding length of the second arm portion are substantially the same, the protruding length of the first arm portion and the protruding length of the second arm portion are mutually exclusive. It is preferable to use different configurations because it is easier to push the arm portion by sandwiching it between two fingers.

Further, in the fall prevention tool of the present invention, the first coil wire of the first coil spring portion does not necessarily have to be wound in a substantially hexagonal shape, and other polygonal shapes such as a substantially quadrangular shape and a substantially pentagonal shape. It can also be wound in a substantially octagonal shape.

However, if the first coil wire of the first coil spring portion is wound in a substantially hexagonal shape, the first coil spring portion corresponds to the shape of the nut, so that the first coil spring is on the side surface of the nut. This is preferable because it makes it easier for the portion to hit and further suppresses the rotation of the nut in the loosening direction.

Further, in the fall prevention tool of the present invention, the curvature of the protruding tip of the second arm portion does not necessarily have to be larger than the curvature of the protruding tip of the first arm portion.

However, if the curvature of the protruding tip of the second arm portion is larger than the curvature of the protruding tip of the first arm portion, the force pushing the second arm portion that moves when the diameter of the second coil spring portion is expanded. Can be made smaller than the force for pushing the first arm portion, and as a result, the settling of the coil wire due to excessive pushing of the second arm portion can be suppressed, which is preferable.

Next, a method of attaching the fall-out prevention tool 1 of the first example of the present invention to the bolt 15 and the nut 16 to which the nut 16 is attached will be described.

The first arm portion 4 and the second arm portion 5 provided in the fall prevention device 1 of the present invention are pushed in the pressurizing direction 11 shown in FIG. 2 by using, for example, a thumb and an index finger or a middle finger, respectively.

Then, the first arm portion 4 and the second arm portion 5 move in a direction approaching each other, and the inner diameter of the second coil spring portion 3 expands.
With the inner diameter of the second coil spring portion 3 expanded, the fall prevention tool 1 of the present invention is surrounded by the second coil wire of the second coil spring portion 3 as shown in FIG. 3 without rotating. The leg portion 15B of the bolt 15 in which the screw groove 15C and the screw thread 15D are formed is inserted into the space.

At this time, the first connection point 13 which is the connection point between one end of the second coil wire 3A and the third coil wire 4A, and the other end of the second coil wire 3A and the fourth coil wire The second connection point 14, which is the connection point with the wire 5A, does not easily enter the space surrounded by the second coil strands of the second coil spring portion 3, and thus interferes with the insertion of the leg portion 15B of the bolt 15. There is no such thing.

Further, at this time, the winding radius of the first coil spring portion 2 is larger than the winding radius of the second coil spring portion 3, and is a winding radius having a size that allows contact with the side surface of the nut 16. The leg portion 15B of the bolt 15 and the nut 16 are also inserted into the space surrounded by the first coil wire of the first coil spring portion 2.

Then, the top portion 2B of the first coil spring portion 2 of the fall prevention tool 1 of the present invention is brought into contact with the corner portion of the nut 16 and at a position corresponding to the screw groove 15C formed in the leg portion 15B of the bolt 15. After arranging the second coil wire 3B of the second coil spring portion 3, the thumb and index finger or middle finger are separated from the first arm portion 4 and the second arm portion 5, respectively.

Then, the first arm portion 4 and the second arm portion 5 move in directions away from each other, the inner diameter of the second coil spring portion 3 that has expanded is reduced and returned to the original position, and the second coil spring portion 3 is the second. The coil wire 3B of 2 fits into the thread groove 15C.
At this time, the contraction force suppresses the rotation of the second coil spring portion 3 in the same direction as the loosening direction of the nut 16, so that the nut 16 also hits the second coil spring portion 3 and the rotation in the loosening direction is suppressed. It is possible to prevent the nut 16 from falling off.

Further, even if the nut 16 tries to rotate in the loosening direction, the first coil spring portion 2 hits the nut 16 and the nut 16 is hard to move any more. Therefore, it is possible to prevent the nut 16 from rotating in the loosening direction.

FIG. 4 is a schematic plan view showing a fall prevention device of a second example to which the present invention is applied.

The fall prevention tool 21 of the second example of the present invention shown in FIG. 4 includes a first coil spring portion 22.
Here, the first coil spring portion 22 has a first coil wire 22A.
Further, the first coil wire 22A includes a portion wound in a substantially hexagonal shape with a winding radius having a size that allows contact with the side surface of the nut.

That is, the shape of the first coil spring portion 22 in the plane extending in the same direction as the winding radius direction of the first coil spring portion 22 is substantially hexagonal, and the first coil spring portion 22 has six tops 22B.

Further, the fall prevention tool 21 of the present invention includes a second coil spring portion 23.
Here, the second coil spring portion 23 has a second coil wire 23A.

Further, the second coil wire 23A extends in a direction substantially orthogonal to the winding radius direction of the first coil spring portion 22 and is centered on the central axis 26 passing through the winding center of the first coil spring portion. In addition, the coil spring portion 22 is wound with a winding radius smaller than the winding radius of the first coil spring portion 22 and having substantially the same diameter in a substantially circular shape.
Further, the central axis 26 is a virtual straight line having no substance.

That is, the shape of the second coil spring portion 23 in the plane extending in the same direction as the winding radial direction of the second coil spring portion 23 is substantially circular.
Further, the inner diameter of the second coil spring portion 23 is slightly smaller than the outer diameter of the leg portion of the bolt. This is to generate austerity force.

Further, the second coil spring portion 23 is arranged at a position different from the position of the first coil spring portion 22 in the direction in which the central axis 26 extends.

Further, the fall prevention tool 21 of the present invention includes a first arm portion 24.
Here, the first arm portion 24 has a third coil wire 24A.

Further, one end of the third coil wire 24A is connected to one end of the first coil wire 22A of the first coil spring portion 22, and the side of the third coil wire 24A opposite to one end. The other end of the second coil spring portion 23 is connected to one end of the second coil wire 23A, and the third coil wire 24A projects in a direction away from the central axis 26.

Further, the protruding tip 24B of the first arm portion 24 is curved.

Further, the fall prevention tool 21 of the present invention includes a second arm portion 25.
Here, the second arm portion 25 has a fourth coil wire 25A.

Further, the fourth coil wire 25A is connected to the other end of the second coil wire 23A of the second coil spring portion 23, which is opposite to one end connected to the third coil wire 24A. And, it protrudes in the direction away from the central axis 26.

Further, the protruding tip 25B of the second arm portion 25 is curved.

Further, the curvature of the protruding tip 25B of the second arm portion 25 is larger than the curvature of the protruding tip 24B of the first arm portion 24.
That is, the protruding tip 24B of the first arm portion 24 is curved more gently than the protruding tip 25B of the second arm portion 25.

Further, the first wire 27 connecting one end of the wound second coil wire 23A and the central axis 26, and the other end of the wound second coil wire 23A and the central axis 26 are connected. The central angle 29, which is the angle between the second line 28 and the central axis 26 when viewed from the central axis 26, is 90 ° or more and 180 ° or less.
In the example shown in FIG. 4, the central angle 29 is 180 °.

Further, the first connection point 30 which is the connection point between one end of the second coil wire 23A and the third coil wire 24A, and the other end of the second coil wire 23A and the fourth coil wire The second connection points 31, which are the connection points with the 25A, are curved.

Further, the protruding length of the first arm portion 24 and the protruding length of the second arm portion 25 are substantially the same as each other.
That is, the length from the first connection point 30 to the protruding tip 24B of the first arm portion 24 and the length from the second connection point 31 to the protruding tip 25B of the second arm portion 25 are substantially the same. is there.

Further, similarly to the fall prevention tool 1 of the first example of the present invention, the central angle 29 of the fall prevention tool 21 of the second example of the present invention is also 90 ° or more and 180 ° or less, so that the first connection location The 30 and the second connection point 31 intersect with a virtual substantially circular body (not shown).

Further, in the method of attaching the fall prevention tool 21 of the second example of the present invention to the bolt to which the nut is attached and the nut, the fall prevention tool 1 of the first example of the present invention is attached to the bolt to which the nut is attached. Since it is the same as the method of attaching to the nut, the description thereof will be omitted.

As described above, in the fall prevention tool of the present invention, in addition to the first wire connecting one end of the wound second coil wire and the central axis, and the wound second coil wire. Since the angle between the second line connecting the end and the central axis when viewed in the direction in which the central axis extends is 110 ° or 180 °, that is, 90 ° or more and 180 ° or less, this angle is less than 90 °. The first connection point and the second connection point are located at positions farther from the winding center of the second coil spring portion than in the case of, and the first connection portion is used to expand the diameter of the second coil spring portion. When the arm portion and the second arm portion are brought close to each other, the first connection portion and the second connection portion are surrounded by the inside of the second coil spring portion, that is, the second coil wire of the second coil spring portion. It is difficult to enter the space.

Therefore, the first connection point and the second connection point do not interfere with the insertion of the bolt leg into the space surrounded by the second coil wire of the second coil spring part, and thus the present invention. The fall-prevention device is easy to attach to the bolt.

1 Falling prevention tool 2 1st coil wire 2A 1st coil wire 2B Top 3 2nd coil spring 3A 2nd coil wire 4 1st arm 4A 3rd coil wire 4B 1st arm Protruding tip of part 5 2nd arm part 5A 4th coil wire 5B Protruding tip of 2nd arm part 6 Virtual substantially circular body 7 1st central axis 8 2nd central axis 9 1st line 10 2nd wire 11 Pressurizing direction 12 Central angle 13 1st connection point 14 2nd connection point 15 Bolt 15A Head 15B Leg 15C Thread groove 15D Thread 16 Nut 21 Falling prevention tool 22 1st coil spring part 22A 1st coil wire 22B Top 23 2nd coil spring 23A 2nd coil wire 24 1st arm 24A 3rd coil wire 24B Protruding tip of 1st arm 25 2nd arm 25A 4th coil wire 25B Protruding tip of 2nd arm 26 Central axis 27 1st wire 28 2nd wire 29 Central angle 30 1st connection point 31 2nd connection point

Claims (5)

A first coil spring portion having a winding radius of a predetermined size and having a first coil wire including a portion wound in a polygonal shape, and a first coil spring portion.
It extends in a direction substantially orthogonal to the winding radius direction of the first coil spring portion, and is centered on the central axis passing through the winding center of the first coil spring portion, and has substantially the same diameter in a substantially circular shape. The position of the first coil spring portion in the direction in which the central axis extends the second coil strand that is wound with a winding radius smaller than the winding radius of the first coil spring portion. The second coil spring part located at a different position from
One end is connected to one end of the first coil wire of the first coil spring portion, and the other end of the second coil spring portion opposite to the one end is of the second coil wire of the second coil spring portion. A first arm portion that is connected to one end and has a third coil wire that protrudes in a direction away from the central axis.
The second coil wire of the second coil spring portion is connected to the other end of the second coil wire, which is opposite to one end connected to the third coil wire, and protrudes in a direction away from the central axis. With a second arm portion having a fourth coil wire
A first wire connecting the one end of the wound second coil wire and the central axis, and a first wire connecting the other end of the wound second coil wire with the center axis. The angle between the two wires when viewed in the direction in which the central axis extends extends is 90 ° or more and 180 ° or less, and the one end of the second coil strand and the third coil strand are A fall-prevention tool in which the first connection point and the second connection point, which is the connection point between the other end of the second coil wire and the fourth coil wire, are curved. The fall-off preventive device according to claim 1, wherein the protruding length of the first arm portion and the protruding length of the second arm portion are substantially the same as each other. The fall-prevention tool according to claim 1 or 2, wherein the first coil wire of the first coil spring portion is wound in a substantially hexagonal shape. The protruding tip of the first arm portion and the protruding tip of the second arm portion are curved, and the curvature of the protruding tip of the second arm portion is larger than that of the first arm portion. The fall-off preventive device according to claim 1, 2, or 3, which is larger than the curvature of the protruding tip. A first coil spring portion having a winding radius of a predetermined size and having a first coil wire including a portion wound in a polygonal shape, and a first coil spring portion.
It extends in a direction substantially orthogonal to the winding radius direction of the first coil spring portion, and is substantially identical to a substantially circular shape centered on the first central axis passing through the winding center of the first coil spring portion. It has a second coil wire that has a diameter and is wound with a winding radius smaller than the winding radius of the first coil spring portion, and has the same first wire in the direction in which the first central axis extends. A second coil spring portion arranged at a position different from the position of the first coil spring portion, and
One end is connected to one end of the first coil wire of the first coil spring portion, and the other end of the second coil spring portion opposite to the one end is of the second coil wire of the second coil spring portion. A first arm portion that is connected to one end and has a third coil wire that protrudes in a direction away from the first central axis.
The second coil wire of the second coil spring portion is connected to the other end of the second coil wire, which is opposite to one end connected to the third coil wire, and is separated from the first central axis. A second arm portion having a fourth coil wire protruding in the direction is provided.
The first connection point, which is the connection point between the one end of the second coil wire and the third coil wire, the other end of the second coil wire, and the fourth coil wire. The second connection point, which is the connection point of the above, has a radius larger than the winding radius of the second coil spring portion about the second central axis extending substantially parallel to the first central axis. A fourth coil element that intersects with a substantially circular body and that connects one end of the second coil element and the third coil element, and the other end of the second coil element and the fourth coil element. A fall-prevention device with curved connections to the wires.

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