JP6226344B1 - Security nut - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a socket wrench to enable inexpensive manufacturing by cold heading and to maintain a fastening force by a high axial force, and to improve a loosening prevention effect without discarding a broken hexagonal portion. To provide a security nut that prevents malfunctions during operation and allows easy adjustment of rupture torque values and dimensional management. A tapered nut portion 2 formed in a truncated cone shape, a hexagonal nut-like tightening nut portion 3, and the tightening nut portion 3 are connected to the upper bottom of the tapered nut portion 2 so as to be separable from each other. A security nut 1 having a breaking separation portion 4, wherein a diameter of an upper base of the tapered nut portion 2 is formed to be larger than a diagonal length of the tightening nut portion 3, and the breaking separation portion 4 is provided only on two opposite sides of the tightening nut portion 3. [Selection] Figure 1

Description

  The present invention relates to a security nut that is prevented from being removed by a general fastening tool.

  A conventional general nut is formed in a polygonal shape such as a hexagon, and can be easily loosened by using a general tool such as a socket wrench or a spanner. For this reason, thefts of facilities such as solar panels, air conditioner outdoor units, surveillance cameras, etc., as well as metal products, various machines and appliances, are frequently occurring. Therefore, the nut used in such a case is not only difficult to remove but also a perfect anti-theft measure is required.

  In order to solve such a problem, an invention related to a security nut in which the nut is formed in a truncated cone shape and prevented from being removed by a general tool has been proposed. For example, in Japanese Patent Application Laid-Open No. 2012-17832, a nut is composed of a truncated cone portion and a square portion, and the square portion is broken when the rotational operation force of the nut reaches a predetermined torque value. Thus, a fastening structure has been proposed in which a connecting portion between the truncated cone portion and the angular portion has a concave groove formed in an annular shape over the entire circumference (Patent Document 1). According to this Patent Document 1, a stable fastening force can be obtained by controlling the breaking torque value of the concave groove to be constant, and since the square portion is broken, the nut cannot be operated in the reverse rotation, and theft. It is said that the prevention function can be exhibited. Further, an insertion hole without a female screw groove is formed at the rotation center position of the angular portion, and the concave groove can be broken at a low torque value.

JP 2012-17832 A

  However, in the invention described in Patent Document 1, when a bolt size of 6 to 50 mm is required, and further, anti-vibration and soundproofing (rubber seat), resin base, etc. are required to be fastened with low torque, Since the processing accuracy of the thin groove portion is required, the cost increases. Further, there is a problem that the groove portion is deformed during transportation. Furthermore, since the sharp fractured surface is exposed after the angular part is broken and removed, there is a risk of injury and the design is not beautiful. In addition, the removed horns must be treated as industrial waste, which is troublesome and costly, and valuable materials are wasted in the first place.

  The present invention has been made to solve the above-described problems, and enables inexpensive production by cold heading, and maintains a fastening force by a high axial force while breaking the hexagonal portion. An object of the present invention is to provide a security nut that can be used to improve the anti-loosening effect without discarding, prevent problems during the fastening operation with a socket wrench, and easily adjust the break torque value and manage the dimensions.

  The security nut according to the present invention is manufactured by an inexpensive manufacturing method by cold heading, and solves the problem of improving the loosening prevention effect without discarding the hexagonal portion while easily breaking the hexagonal portion while maintaining a high fastening force. In order to do so, a tapered nut portion formed in a truncated cone shape, a hexagonal nut-like tightening nut portion, a breaking separation portion formed by connecting the tightening nut portion to the upper bottom of the tapered nut portion so as to be breakable and separable A diameter of an upper base of the taper nut portion is greater than or equal to a diagonal length of the tightening nut portion, and the breaking separation portion is relative to the tightening nut portion. It is provided only on two sides.

  According to the present invention, it is possible to manufacture at low cost by cold heading, and while maintaining a fastening force by a high axial force, it is used to improve a loosening prevention effect without discarding a broken hexagon part, and a socket. The trouble at the time of fastening operation with a wrench can be prevented, and the breaking torque value can be easily adjusted and the dimensions can be managed.

It is a perspective view showing one embodiment of a security nut concerning the present invention. It is a front view which shows the security nut of this embodiment. It is a top view which shows the security nut of this embodiment. It is AA sectional drawing in FIG. It is a side view which shows the security nut of this embodiment. It is a figure which shows the usage example of the security nut of this embodiment, Comprising: (a) The use condition in the case of making it fasten to the fixing bolt penetrated by the to-be-fastened member, (b) Fastening to the dimension bolt penetrated by the to-be-fastened member It is a figure which shows the use condition in the case of making it, and the use condition in the case of making it fasten from both sides to the dimension bolt which was penetrated by the (c) two to-be-fastened members.

  Hereinafter, an embodiment of a security nut according to the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 2, the security nut 1 of the present embodiment includes a tapered nut portion 2 formed in a truncated cone shape, a hexagon nut-like tightening nut portion 3, and the tightening nut portion 3. It has the fracture separation part 4 connected to the upper bottom of the taper nut part 2 so that fracture separation is possible. Hereinafter, each configuration will be described in detail.

  The taper nut portion 2 is a nut that is fastened to the bolt 6 or the like on the fastened member 5 side, and as shown in FIGS. 3 and 4, a female screw groove is formed at the center of rotation, and the outer peripheral portion is a cone. It is formed in a trapezoidal shape. The taper nut portion 2 is formed at an inclination angle that cannot be removed by a general fastening tool after fastening. For example, as shown in FIG. Preferably about 30 degrees.

  In addition, the diameter of the upper base of the taper nut portion 2 is a tightening nut as shown in FIGS. 2, 3 and 5 so that it can be manufactured by cold heading which can be manufactured at a lower cost than high-precision cutting. It is formed in a size that is greater than the length of the diagonal line of the portion 3. Cold heading is a processing method in which a metal is formed by pressure at room temperature, and a product is mainly produced by a combination of a punch that applies pressure to a metal member and a die that is a mold. That is, the tapered nut portion 2 of the present embodiment is formed so as to be larger than the tightening nut portion 3 on the upper bottom side and to expand toward the lower bottom in order to be formed by the punch and the die. Yes.

  The tightening nut portion 3 is for transmitting torque to the tapered nut portion 2 and is formed in a hexagonal nut shape that can be fitted or locked to a general socket wrench, spanner or the like. Since the tightening nut portion 3 can remain on the bolt 6 on the fastened member 5 side after breaking and separating from the taper nut portion 2, as shown in FIGS. 3 and 4, the female screw of the taper nut portion 2 is located at the rotation center position. A female screw groove continuous with the groove is formed.

  The break separating portion 4 connects the tightening nut portion 3 to the upper bottom of the taper nut portion 2 and breaks when the torque of a predetermined level or more is applied to separate the tightening nut portion 3 from the taper nut portion 2. . The breaking separation portion 4 is provided only on two opposite sides of the tightening nut portion 3 in order to concentrate stress due to torque transmitted from the tightening nut portion 3. In the present embodiment, the breaking separation portion 4 is a fastening with the shortest mutual distance so that fastening by a socket wrench or the like is not hindered by the remaining convex portion of the breaking separation portion 4 remaining on the upper bottom of the taper nut portion 2 after breaking separation. It is formed at a substantially central position on the side surface of the attached nut portion 3. That is, by forming the break separating portion 4 only on the two opposite sides as described above, there is a possibility that the residual convex portion after the break will fit below the corner of the tightening nut portion 3 and jump out outward. Since it is low, it can prevent obstructing the tightening operation of a socket wrench or the like.

  Further, as shown in FIGS. 2 and 4, each breaking separation portion 4 is formed to have a predetermined width in the circumferential direction with respect to the side surface of the tightening nut portion 3, and the dimension of the width is set. By appropriately setting, the magnitude of the value of the torque to break is adjusted. The fracture separation part 4 can be formed by cutting with a pair of rotary cutters installed in parallel between the upper bottom of the taper nut part 2 and the tightening nut part 3, for example, depending on the size of the nut. By adjusting the gap between the pair of rotary cutters, the thickness of each rotary cutter, and the like, the breaking torque value of the breaking separator 4 is adjusted, and the dimensions are controlled.

  Next, the operation of each component in the security nut 1 of the present embodiment will be described.

  As shown in FIG. 6, the security nut 1 of the present embodiment is fastened to the bolt 6 inserted through the fastened member 5. Specifically, a fastening tool such as a socket wrench or a spanner is fitted or engaged with the fastening nut portion 3 and is screwed into the bolt 6 while being rotated by the fastening tool.

  The security nut 1 is screwed until the taper nut portion 2 comes into contact with the fastened member 5. In this state, when further torque is applied to the tightening nut portion 3, the taper nut portion 2 cannot be screwed, so that the torque is applied to the security nut 1. At this time, the fracture separation portion 4 is provided only on two opposite sides of the tightening nut portion 3 and is formed with a smaller size than the tapered nut portion 2 and the tightening nut portion 3. Stress due to torque is concentrated.

  And the fracture | rupture isolation | separation part 4 will fracture | rupture when the torque more than a fracture | rupture torque value is applied, and the taper nut part 2 and the clamping nut part 3 will isolate | separate. At this time, the tapered nut portion 2 is securely fastened to the fastened member 5 by the fastening force until the fastening nut portion 3 is separated.

  Further, in this embodiment, the separated tightening nut portion 3 is further torqued to be tightened to the taper nut portion 2 side and left on the bolt 6 inserted through the fastened member 5. At this time, even if the rupture separation portion 4 that has been separated remains on the upper bottom of the taper nut portion 2 in a convex shape, the rupture separation portion 4 is positioned at approximately the center position of the two opposing sides of the tightening nut portion 3. Since it is formed, the residual convex portion is easy to fit below the corner portion of the tightening nut portion 3, and does not come into contact with a fastening tool such as a socket wrench to prevent rotation or damage the socket wrench. .

  Further, the tightening nut portion 3 remaining on the bolt 6 has a step difference between the female screw of the taper nut portion 2 and the female screw of the tightening nut portion 3. The contact area of the screw increases, and the effect of preventing loosening is exhibited. Therefore, the remaining tightening nut portion 3 does not need to be treated as industrial waste, but also functions as a slack stop for the taper nut portion 2.

  On the other hand, even if the tightening nut portion 3 is rotated and loosened in the opposite direction, the torque is not transmitted to the taper nut portion 2 because it is separated from the taper nut portion 2. In addition, since the taper nut portion 2 cannot be fastened with a general fastening tool, it is possible to prevent theft of metal products, various machines and instruments, solar panel facilities, etc., as with conventional security nuts. .

According to the present embodiment as described above, the following effects can be obtained.
1. By providing the rupture separation part 4 only on the two opposite sides of the tightening nut part 3, the rupture separation part 4 is appropriately broken by concentrating the stress due to the torque while maintaining a fastening force by a high axial force. be able to.
2. The remaining convex portion after the breakage does not disturb the tightening operation of the socket wrench or the like.
3. Since it becomes easy to manage the dimensions of the breaking separation portion 4 that determines the value of the breaking torque, the breaking torque value can be easily adjusted.
4). The taper nut portion 2 is formed by cold heading, which is a relatively inexpensive manufacturing method, by forming the upper bottom side of the taper nut portion 2 to be larger than the tightening nut portion 3 and expanding the diameter toward the lower bottom. Can do.
5. By leaving the tightening nut portion 3 on the bolt 6, waste as an industrial waste is eliminated.
6). The function of the loosening prevention nut is enhanced by the remaining tightening nut portion 3 and injuries due to the fracture surface are prevented, and the design after fastening is beautiful.

  The security nut according to the present invention is not limited to the above-described embodiment, and can be changed as appropriate.

1 Security nut
2 Tapered nut part 3 Tightening nut part 4 Breaking separation part 5 Fastened member 6 Bolt

Claims (1)

A frustoconical tapered nut portion formed in a shape, a hexagonal nut-like fastening nut portion, and a lower surface and said tapered nut portion of the upper base and the fracture splitting linked to comprising fracture splitting portion of the nut are tightened A security nut having
The diameter of the upper base of the tapered nut portion is formed to be larger than the diagonal length of the tightening nut portion, and the breaking separation portion is perpendicular to the vertical direction of the two opposite side surfaces of the tightening nut portion. laterally together it is only provided on the lower surface of a substantially central position below the fastening nut of the up-down direction between the lower surface of the upper base and the fastening nut of the fracture splitting portion the tapered nut portion for The security nut, which is formed integrally with the tapered nut portion and the tightening nut portion with a gap in between.

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