JP2023009902A - Falling prevention tool - Google Patents

Abstract

To provide a falling prevention tool capable of being mounted easily, and hard to come off from a bolt or nut.SOLUTION: A falling prevention tool 1 prevents a bolt or nut from falling out. The falling prevention tool 1 has an annular part 2 that is press-fitted onto a screw part of the bolt.SELECTED DRAWING: Figure 1

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fall-off prevention tool for preventing a nut screwed onto a bolt from falling off, and for preventing a bolt inserted into a bolt hole from coming off from the bolt hole.

For example, suspension bolt support fittings are known for supporting and fixing various steel materials such as channel materials at intermediate positions of suspension bolts suspended from a ceiling slab or the like. These metal fittings, bolts, and nuts must be packed separately, and must be temporarily assembled at the work site to be attached to the suspension bolts, and the work efficiency is not very high. For this reason, it is preferable from the viewpoint of work efficiency to ship the metal fittings in a temporarily assembled state in which the metal fittings are temporarily assembled while loosely screwing the nut onto the bolt, and then perform only the assembly work from the temporarily assembled state at the work site. It is difficult to avoid a situation in which the nut falls off from the bolt due to the vibration of the bolt or the like, and the temporarily assembled state is disassembled into pieces.

Various nut locking tools have existed in the past, and it may be possible to use them for temporary assembly (see Patent Documents 1 and 2). However, most of the nut locking devices have a coil spring shape, and after tightening the bolt and nut, it is necessary to insert them while screwing them from the lower end of the bolt. Since it cannot be used in situations where there is no gap larger than the length of the spring on the lower side, it cannot be said to be convenient for temporary assembly. In addition, since it is manufactured by bending a steel wire, it is difficult to reduce the cost, and it has not been excellent in cost performance. Furthermore, the tip of the wire rod is hooked on the side surface of the nut so that the rotation of the nut is stopped, and there is also the problem that the wire is easily detached from the nut.

JP 2019-203316 A JP-A-2002-333005

It is an object of the present invention to provide a drop-off prevention tool that can be easily attached and is hard to come off from bolts and nuts.

A fall prevention tool for preventing a bolt or nut from falling out according to the present embodiment has an annular portion press-fitted onto a threaded portion of the bolt.

1 is a perspective view showing a fall prevention tool according to a first embodiment of the present invention; FIG. FIG. 2 is a plan view of the fall prevention tool of FIG. 1; FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2; FIG. 2 is a side view of the fall prevention tool of FIG. 1; (a) is a side view showing how the drop-off prevention tool in FIG. ) is a bottom view showing how the annular portion of the drop-off prevention device is expanded in diameter. (a) is an exploded view showing the state in which the drop-off prevention tool in FIG. c) is a side view of (b), and (d) is a bottom view of (b). It is a figure which shows a mode that the fall prevention tool of FIG. 1 is reversed and it mounts|wears with a bolt and a hexagonal nut. (a) is an exploded view showing the state in which the fall prevention tool in FIG. 7 is attached to the bolt and the hexagonal nut, (b) is a perspective view showing the state in which the fall prevention tool in (a) is attached to the bolt and the hexagonal nut, ( c) is a side view of (b), and (d) is a bottom view of (b). FIG. 10 is a perspective view showing a fall prevention tool according to a second embodiment of the present invention; FIG. 10 is a plan view of the fall prevention tool of FIG. 9; FIG. 11 is a cross-sectional view taken along line AA of FIG. 10; FIG. 10 is a side view of the fall prevention tool of FIG. 9; FIG. 10 is a diagram showing how the drop-off prevention tool of FIG. 9 is attached to a bolt and a plate nut; (a) is a developed view showing a state in which the drop-off preventing tool of FIG. 9 is attached to the bolt and the plate nut, and (b) is a side view showing a state in which the drop-off preventing tool is attached to the bolt and the plate nut. It is a perspective view which shows the modification of the drop-off prevention tool which concerns on 2nd Embodiment. FIG. 11 is a perspective view showing another modification of the drop-off prevention tool according to the second embodiment; FIG. 11 is a perspective view showing still another modification of the fall prevention tool according to the second embodiment;

Hereinafter, the falling prevention tool according to this embodiment will be described with reference to the drawings. In the following description, components having the same functions and configurations are denoted by the same reference numerals, and redundant description will be given only when necessary.
(First embodiment)
1 to 4 show a drop-off prevention tool according to this embodiment. FIG. 5 shows how the drop-off prevention tool is attached to the bolt and nut, and FIG. 6 shows how the drop-off prevention tool is attached to the bolt and nut. In the following description, an example in which the stopper 1 according to the present embodiment is adapted to the hexagonal nut 30 will be described, but it can also be adapted to other types of square nuts such as a square nut.

The coming-off prevention tool 1 prevents the nut 30 screwed on the bolt 20 from coming off, and also prevents the bolt 20 inserted into the bolt hole drilled in the fitting or the like from coming off from the bolt hole. The drop-off prevention tool 1 is an integrated resin molding made of polyacetal (POM), polyamide (PA), polycarbonate (PC), or the like, which typically has high abrasion resistance and high elasticity as a resin. The fall prevention tool 1 has an annular portion 2, and a rectangular plate-shaped abutment portion 4 is coupled to the outer circumference of the annular portion 2. As shown in FIG. An arc portion of the annular portion 2 is cut out at an angle of less than 180 degrees, typically in the range of 20° to 30°. It is located on the opposite side that is shifted by 180 degrees in the circumferential direction. A worker can pinch the abutment part 4 and push the annular part 2 into the bolt 20 from the notch 3 .

The inner diameter W0 of the annular portion 2 is slightly shorter than the outer diameter (diameter) of the threaded portion 22 of the bolt 20 to be mounted. As a result, the annular portion 2 is press-fitted onto the threaded portion 22 of the bolt 20 and clamps the threaded portion 22 due to its elasticity.

The height H1 of the contact portion 4 is longer than the thickness T1 of the annular portion 2, and the bottom surface of the contact portion 4 is aligned with the bottom surface of the annular portion 2. As shown in FIG. In a side view, the contact portion 4 protrudes along the center line C with respect to the annular portion 2 . The contact portion 4 is arranged parallel to the center line C of the annular portion 2 and parallel to the tangent line of the inner circle of the annular portion 2 . The inner surface of the contact portion 4 is substantially 1/2 the width across flats of the hexagonal nut 30 to be screwed into the bolt 20 to prevent falling off from the center line C of the annular portion 2. The inner surface of the abutting portion 4 abuts on one side surface 33 of the hexagonal nut 30 in a state where the annular portion 2 is press-fitted onto the threaded portion 22 of the bolt 20, and are spaced apart by an equivalent distance. Free rotation of the hex nut 30 with respect to the bolt 20 can be suppressed.

Typically, the width W2 of the contact portion 4 is shorter than the outer diameter W1 of the annular portion 2. As shown in FIG. As a result, interference with the wrench and its surroundings can be minimized when attaching the drop-off prevention tool 1 to the bolt 20 and the hexagonal nut 30, and when tightening the bolt 20 with a wrench and fixing the hexagonal nut 30. It is not denied that the width W2 of the contact portion 4 is longer than or equal to the outer diameter W1 of the annular portion 2 .

A pair of guide pieces 5 are provided at both end portions of the annular portion 2 in which the notch 3 is formed so as to spread to both sides. When the inner surface of the guide piece 5 is brought into contact with the outer peripheral surface of the threaded portion 22 of the bolt 20 and pushed in as it is, the inner surface of the guide piece 5 moves along the outer peripheral surface of the threaded portion 22 of the bolt 20, As a result, the annular portion 2 is enlarged in diameter so that it can be easily fitted onto the threaded portion 22 of the bolt 20 .

A pair of linear projections 6 that mesh with the thread root of the bolt 20 are provided on the opposing inner surfaces of the annular portion 2 . When the annular portion 2 is pushed into the threaded portion 22 of the bolt 20 from the notch 3, the linear protrusions 6 are formed on the inner surface of the notch 3 on the opposite side thereof as described later so as not to interfere with the pushing movement as much as possible. It is provided along the front-rear center line connecting the center of the recess 7 . With the annular portion 2 press-fitted onto the threaded portion 22 of the bolt 20 , the filamentary projection 6 engages with the root of the bolt 20 to prevent the drop-off prevention tool 1 from being displaced from the bolt 20 . Also, since the filamentary protrusions 6 on the inner surface of the annular portion 2 are engaged with the root of the bolt 20 in the same manner as the hexagonal nut 30, the rotation of the hexagonal nut 30 is fixed by a tightening tool such as a spanner or wrench, and the bolt 20 is tightened. When the shaft is strongly rotated and tightened, the ring part 2 moves along the axial direction of the threaded part 22 of the bolt 20 together with the hexagonal nut 30, so that the stopper 1 does not hinder the tightening of the hexagonal nut 30. . The same is true when loosening the hexagonal nut 30 with respect to the bolt 20 .

An arc-shaped recess 7 is provided on the inner surface of the ring portion 2 opposite to the notch 3 to disperse the stress associated with the diameter expansion of the ring portion 2 and suppress the breakage of the ring portion 2 due to stress concentration. It is designed to

The fall prevention tool 1 is attached to the bolt 20 and the hexagon nut 30 after tightening the object to be fastened between the bolt 20 and the hexagon nut 30, or in a temporary assembly state in which the hexagon nut 30 is loosely screwed onto the bolt 20. is installed.

As shown in FIG. 5( a ), the stopper 1 is arranged below the hexagonal nut 30 when viewed from the head 21 of the bolt 20 . That is, the upper surface of the annular portion 2 is in contact with the lower surface of the hexagonal nut 30 screwed onto the bolt 20, and the contact portion 4 protrudes upward (toward the head portion 21 of the bolt 20) with respect to the annular portion 2. The drop-off prevention tool 1 is arranged in a posture and horizontally approached to the screw part 22 of the bolt 20 from the side thereof. As shown in FIGS. 5(b) and 5(c), the inner surface of the guide piece 5 is brought into contact with the outer peripheral surface of the threaded portion 22 of the bolt 20, and the annular portion 2 retains its elasticity. flares out on both sides to receive the threaded portion 22 . The annular portion 2 is contracted in diameter due to its elasticity and clamps the screw portion 22 . As shown in FIGS. 6(a), 6(b), 6(c), and 6(d), the inner surface of the portion of the contact portion 4 that protrudes from the annular portion 2 is one side surface of the hexagonal nut 30. 33.

Since the annular portion 2 sandwiches the threaded portion 22 , the drop-off prevention device 1 is fixed to the bolt 20 . Further, since the contact portion 4 is in contact with one side surface 33 of the hexagonal nut 30, rotation of the hexagonal nut 30 with respect to the stopper 1 is suppressed. Therefore, the rotation of the hexagon nut 30 with respect to the bolt 20 and the rotation of the bolt 20 with respect to the hexagon nut 30 are restrained via the stopper 1, so that the hexagon nut 30 is loosely screwed onto the bolt 20. However, the hexagonal nut 30 is prevented from coming off from the bolt 20.例文帳に追加Also, when the bolt 20 is inserted through a bolt hole of a metal fitting or the like and screwed into a hexagonal nut 30, the stopper 1 comes into contact with the periphery of the bolt hole to prevent the bolt 20 from falling out of the bolt hole. Moreover, even if there is no nut, it is possible to prevent the bolt 20 from falling out of the bolt hole by attaching the drop-off prevention tool 1 to the bolt 20. - 特許庁

Since the annular portion 2 clamps the threaded portion 22 and the filamentary projection 6 engages with the thread root of the threaded portion 22, the fall prevention tool 1 is prevented from being displaced from the bolt 20, and the abutment portion is fixed. 4 is in surface contact with one side surface 33 of the hexagonal nut 30, the drop-off prevention tool 1 is difficult to come off from the hexagonal nut 30. - 特許庁

In addition, since the anti-dropout tool 1 can be attached to the bolt 20 from the side thereof, the workability of attachment is higher than that of inserting from the lower end (tip) of the bolt 20 . Furthermore, when the bolt 20 and the hexagonal nut 30 are relatively axially rotated to be tightened or loosened, the drop-off prevention tool 1 moves along the axial direction of the threaded portion 22 of the bolt 20 together with the hexagonal nut 30. Since tightening or loosening work with the nut 30 is not hindered, and the drop-off prevention tool 1 is not damaged by tightening, it is suitable for repeated use.

Since the drop-off prevention tool 1 can be manufactured as an integral resin molding, it is excellent in cost performance. It should be noted that it is not denied that the drop-off preventing tool 1 is made of metal having elasticity.

As described above, the drop-off prevention tool 1 is suitable for temporarily assembling the bolt 20, the hexagonal nut 30, and the metal fittings. and work efficiency can be improved.

In the above description, an example in which the drop-off prevention tool 1 is attached to the lower side of the hexagonal nut 30 when viewed from the head 21 of the bolt 20 has been described, but as shown in FIGS. A protective device 1 can also be attached. That is, as shown in FIG. 7, the lower surface of the annular portion 2 is in contact with the upper surface of the hexagonal nut 30 screwed to the bolt 20, and the abutment portion 4 is in a position protruding downward from the annular portion 2. , the drop-off preventing tool 1 is placed horizontally, and the drop-off preventing tool 1 is made to approach the screw part 22 of the bolt 20 from its side. As shown in FIGS. 8(a), 8(b), 8(c), and 8(d), the inner surface of the contact portion 4 projecting downward from the annular portion 2 is one side surface of the hexagonal nut 30. 33. Similar effects can be obtained even when the anti-dropping tool 1 is attached in the opposite direction. In this case, although there is a possibility that the stopper 1 will be damaged by tightening, the loosening of the tightened hexagonal nut 30 can be prevented.

In the above description, the contact portion 4 protrudes in one direction with respect to the ring portion 2 in side view, but the contact portion 4 extends upward and downward with respect to the ring portion 2 in side view. You may comprise so that it may protrude.
(Second embodiment)
9 to 12 show the drop-off prevention tool 10 according to this embodiment. FIG. 13 shows how the stopper 10 is attached to the bolt 20 and the plate nut 40, and FIG. 14 shows how the stopper 10 is attached to the bolt 20 and the plate nut 40. FIG. The drop-off prevention tool 10 is adapted to a grooved plate nut 40 in which a steel plate is bent to have a U-shaped cross section. The plate nut 40 comprises a rectangular bottom plate 41 and a pair of side plates 43 , and a screw hole 42 for screwing the bolt 20 is formed in the center of the bottom plate 41 .

The drop-off prevention tool 10 according to the second embodiment differs from the drop-off prevention tool 1 according to the above-described first embodiment in the contact portion 14 . The parts other than the contact part 14 are the same as those of the stopper 1 according to the first embodiment, so the description is omitted.

The contact portion 14 provided in the drop-off prevention device 10 according to the present embodiment has the same thickness as the thickness T1 of the annular portion 2 and is configured flat with no step above or below the annular portion 2 . The outer diameter W1 of the annular portion 2 is configured to be shorter than the interval between the pair of side plates 43 of the plate nut 40 to be mounted.

The width W3 of the contact portion 14 is configured to be longer than the outer diameter W1 of the annular portion 2, and both ends of the contact portion 14 protrude laterally beyond the annular portion 2 in plan view. The width W3 of the contact portion 14 is appropriately designed to be equal to or slightly shorter than the interval between the pair of side plates 43 of the plate nut 40 to be mounted.

As shown in FIG. 13, the plate nut 40 is screwed onto the bolt 20, and the drop-out prevention device 10 is bolted horizontally with the bottom plate 41 between the bottom plate 41 of the plate nut 40 and the upper edge of the side plate 43. As shown in FIG. The threaded portion 22 of 20 is approached from its side. While inserting the drop-off preventing tool 10 between the pair of side plates 43 of the plate nut 40, the ring part 2 is strongly pushed into the threaded part 22 of the bolt 20, and the drop-off preventing tool 10 is attached to the bolt 20 and the plate nut 40. .

As shown in FIGS. 14(a) and 14(b), the stopper 10 is accommodated inside the plate nut 40, and both ends of the contact portion 14 are in contact with the inner surfaces of the pair of side plates 43 of the plate nut 40. touch. Since the annular portion 2 holds the threaded portion 22 and both ends of the contact portion 14 are in contact with the inner surfaces of the pair of side plates 43 of the plate nut 40, the rotation of the plate nut 40 with respect to the bolt 20 and the plate nut Since the rotation of the bolt 20 with respect to the plate nut 40 is suppressed, the plate nut 40 is prevented from coming off the bolt 20, and the bolt 20 is also prevented from coming off from the plate nut 40. - 特許庁

Also in this embodiment, the same effects as in the first embodiment can be obtained.

In the above description, the contact portion is connected to the annular portion at the position opposite to the notch, but the present invention is not limited to this. Here, for convenience of explanation, the notch 3 is defined as the front side of the ring portion 2 and the depression 7 is defined as the rear side of the ring portion 2 . As shown in FIG. 15, the contact portion 14 may be coupled to either the left or right side portion of the ring portion 2 . In other words, the contact portion 14 is connected to the annular portion 2 between the position of the notch 3 and the position opposite to the notch 3 .

Further, as shown in FIG. 16 , a pair of contact portions 15 as the contact portions 14 are provided on both edges of the notch 3 of the ring portion 2 so as to extend to both the left and right sides and extend from the ring portion 2 to the left and right. It may be coupled to the annular portion 2 so as to protrude. Furthermore, as shown in FIG. 17, a pair of abutting portions 16 may be joined to the left and right side portions of the annular portion 2 .

Of course, the same applies to the contact portion 4 in the first embodiment. A pair of abutting portions forming the portion 4 may be joined to the annular portion 2 so as to expand to both the left and right sides of both edges of the notch 3 , or a pair of abutting portions may be connected to the annular portion 2 . may be coupled to the left and right side portions of the .

The present invention is not limited to the above-described embodiments, and can be modified in various ways without departing from the scope of the present invention at the implementation stage. Further, each embodiment may be implemented in combination as appropriate, in which case the combined effect can be obtained. Furthermore, various inventions are included in the above embodiments, and various inventions can be extracted by combinations selected from a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiments, if the problem can be solved and effects can be obtained, the configuration with the constituent elements deleted can be extracted as an invention.

DESCRIPTION OF SYMBOLS 1... Drop-off prevention tool, 2... Annular part, 3... Notch, 4... Contact part, 5... Guide piece, 6... Linear projection, 7... Hollow.

Claims (11)

In the falling prevention tool for preventing falling of bolts or nuts,
A drop-off prevention device having an annular portion that is press-fitted onto the threaded portion of the bolt. 2. The drop-off prevention device according to claim 1, wherein the inner surface of said annular portion is provided with a linear projection that meshes with the root of said bolt. 3. The drop-off prevention device according to claim 1, wherein a notch is formed in a part of said annular portion and is inserted into the outer peripheral surface of said threaded portion of said bolt from the side. 4. The inner surface of the annular portion is provided with an arcuate recess in order to disperse the stress associated with the expansion of the diameter of the annular portion and to suppress breakage due to stress concentration. The falling prevention device according to item 1. 5. The drop-off prevention device according to claim 1, further comprising an abutment portion that is coupled to the annular portion and abuts on the nut to stop rotation of the nut with respect to the bolt. 6. The drop-off prevention device according to claim 5, wherein the contact portion is coupled to the annular portion at a position on the opposite side of the notch. 6. The drop-off prevention device according to claim 5, wherein the contact portion is coupled to the annular portion between a position of the notch and a position on the opposite side of the notch. 6. The drop-off prevention device according to claim 5, wherein said contact portion comprises a pair of contact portions coupled to both edges of said notch. 9. The falling-off prevention device according to claim 5, wherein the contact portion has a plate shape whose height is longer than the thickness of the annular portion. 10. The falling-off prevention device according to claim 5, wherein the width of the contact portion is longer than the outer diameter of the annular portion. 11. The drop-off prevention device according to any one of claims 5 to 10, wherein the annular portion and the contact portion are integrally molded resin.

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