JPH087134Y2 - Blind rivet for soft materials - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blind rivet, and more particularly to a blind rivet suitable for fastening to a soft material such as resin or aluminum, which blind rivet can be easily removed after fastening.

[0002]

2. Description of the Related Art As a blind rivet for connecting members made of a soft material such as resin or aluminum, a hollow tube-shaped body and a flange formed at one end of the body, and an expansion into the body. The mandrel is housed so that the diameter head is on the side opposite to the flange, and the mandrel shaft extending toward the flange is deformed so that the entire mandrel is pulled out from the body to expand the body. Let
It is known that the body is fastened to a soft material such as resin or aluminum by the enlarged diameter portion of the body and the flange. Unlike those used for hard materials such as steel, such blind rivets for soft materials use a mandrel that pulls out the rivet body while expanding the diameter of the rivet body, allowing the entire mandrel to come out as it is. Is fastened to a soft material. That is, the body of the blind rivet for soft material is simply expanded in diameter so that it does not buckle and deform like the one for hard material, and the expanded diameter body bites into the hole wall surface of the soft material and is fastened. As a result, the soft material can be securely fastened without being damaged and the deformation of the soft material is prevented. Such blind rivets are widely used because they have a great advantage that they can be fastened from one side even when it is impossible to insert a hand to the back side like a large panel.

However, a drawback of such a blind rivet for soft materials is that it is not easy to release (ie, remove) the fastening with the blind rivet after fastening. Generally, in the case of removal, the rivet body must be destroyed, and at this time, there is a fear that the panel may be damaged. For this reason, removable blind rivets have been developed. In this blind rivet, a male screw is formed on the outer peripheral surface of the body, the diameter of the body is expanded by pulling out the mandrel having a hexagonal cross section, and the hole of the body after the mandrel is removed is formed into a hexagon. . Therefore, at the time of fastening, the screw bites into the surface of the hole of the soft material for mounting, and if the wrench is inserted into the hole of the body and rotated, the body is removed from the soft material.

[0004]

However, the above-mentioned removable blind rivet for soft material also has some drawbacks. One of them is that the body is expanded by pulling out the mandrel with a hexagonal cross section, so the body is expanded into a hexagonal shape, and there are only six places to bite into the wall surface of the panel hole, and the fastening strength is high. There is no point. And, since the hole expanded by pulling out the mandrel remains in the body, the force that resists the force to shrink the body from the outer peripheral surface toward the hole is weak, the diameter of the body becomes small and the fastening force is reduced. There is a drawback that it becomes weak and the connected soft materials are easily separated from each other. Further, since the hexagonal hole of the body portion is formed by pulling out the hexagonal mandrel, it is difficult to form the hexagonal hole accurately, and it is difficult to insert the wrench.

Therefore, an object of the present invention is to provide a blind rivet for a soft material, which can not only securely fasten the soft material but also can be easily removed.

[0006]

In order to achieve the above object, according to the present invention, a hollow tube-shaped body portion, a flange formed at one end of the body portion, and an expanding head in the body portion are provided. The mandrel is housed on the side opposite to the flange, and the shank of the mandrel extending to the side of the flange is pulled out from the body to deform the body to expand the diameter of the body. It is a blind rivet that is fastened to a soft material such as resin or aluminum by a diameter part and a flange.A male screw is formed on the outer peripheral surface of the body part, and the mandrel is located near the expanding head. A reduced-diameter portion is formed, and the reduced-diameter portion is formed to have such strength that the mandrel breaks at the reduced-diameter portion and leaves the expanded-diameter head in the trunk in the mandrel withdrawing operation, The body is on the flange Blind rivet for a soft material is provided, wherein a rolling possible means are provided.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show a first embodiment. The blind rivet 1 for soft material of this embodiment has a hollow tubular body 2 and a flange 3 formed at one end of the body 2, and a diametrical expansion head 4 in the body 2 and a flange 3. And a mandrel 5 accommodated on the opposite side, and a male screw 6 is formed on the outer peripheral surface of the body 2.
In the present invention, the mandrel 5 is formed with a reduced diameter portion 7 near the enlarged diameter head 4. In particular, when the mandrel 5 is pulled out when the mandrel 5 is pulled out, the reduced-diameter portion 7 is broken at the reduced-diameter portion 7 so that the enlarged-diameter head 4 is attached to the body portion 2.
It is formed so as to have strength enough to be left inside. Further, the flange 3 is provided with a sliding groove 8 as a means for rotating the body portion 2 so that it can be rotated by a flat-blade screwdriver or the like. The cross section of the enlarged diameter head 4 is preferably substantially circular and has a larger diameter than the hole of the body 2. Before fastening, the tip of the body portion 2 (the lower end side in the drawing) is formed so as to have a diameter smaller than that of the flange 3. This is preferable because when the body portion 2 is expanded by fastening, a male screw member having the same diameter can be formed as shown in FIG.

As shown in FIG. 2, the blind rivet 1 having such a structure is to be fastened to connect two soft material (for example, resin, aluminum, copper, etc.) panels 9 and 10 as shown in FIG. The shank of the nose of the blind rivet fastening tool grips the shaft portion of the mandrel 5 extending to the side, and the tool is operated to pull the mandrel 5 out of the body 2. By this pulling action,
The diameter-expanding head 4 of the mandrel 5 advances in the hole of the body 2 to expand the diameter of the body 2, but as it approaches the flange 3,
The force for expanding the diameter of the body portion 2 increases, and the head portion 4 tries to stay at a position close to the flange 3. Therefore, when the mandrel 5 is further pulled, the mandrel 5 is broken at the reduced diameter portion 7 in FIG. 2, and the head 4 is inserted into the hole 1 of the body 2 as shown in FIG.
Remain in 1. That is, not only the body 2 is expanded in diameter by the mandrel head 4, but also the head 4 remains on the body 2, so that even if a force to reduce the diameter of the expanded body 2 acts, Can sufficiently resist the reducing force. As a result, the enlarged male screw 6 of the body 2 bites into the surface of the hole 12 of the panel 10 with sufficient force, and the bite and the flange 3 connect the panels 9 and 10 to each other. The hole 13 of the panel 9 should be larger than the outer diameter of the body 2,
This is convenient in the detaching operation described below.

After fastening, when a flat-blade screwdriver or the like is applied to the groove 8 of the flange 3 to rotate the flange, the body 2 rotates and the male screw 6 bites into the hole 12 of the panel 10.
The body portion 2 comes out along with the flange 3 along with, and then the panel 9 is removed from the panel 10 as shown in FIG. In this rotation, the hole 13 of the panel 9 has a larger diameter than that of the body portion 2, and therefore does not interfere with the rotation. In this way, the connected soft material panels 9 and 10 can be detached even after fastening by a simple operation from one side.
Even when reattaching, the body 2 is attached to the hole 1 of the panel 9.
3 can be passed through and the groove 8 of the flange 3 can be used to rotate with a flat-blade screwdriver or the like for easy re-fastening.

5 to 7 show an example in which the blind rivet of the first embodiment is used in a place different from that of the example of FIG. 5 and 6 show an example in which the panel 17 is connected to the blind hole 16 of the member 15 made of a soft material, and can be easily removed by using the groove 8 after the fastening in FIG. Unlike the example shown in FIG. 2, the example shown in FIG. 7 shows an example in which the diameter of the hole 13 of the panel 9 is made small so that the hole 13 penetrates into the male screw 6 of the body 2 to improve the strength of the connection.

8 to 10 disclose a second embodiment. In this embodiment, a large-diameter cylindrical body portion 18 close to the outer diameter of the male screw is formed between the male screw 6 on the outer peripheral surface of the body 2 and the flange 2. This large-diameter tubular body portion 18
Contributes to obstructing the advancement of the enlarged-diameter head 4 of the mandrel 5 and functions to leave the fractured enlarged-diameter head 4 in front of the large-diameter cylindrical body portion 18. Therefore, as shown in FIG.
The area where the male screw 6 bites into the hole of the panel 10 can be increased, and the connection strength can be further increased. In this case, if the length of the head portion 4 is made slightly longer, it is possible to resist the diameter reducing force of the body portion 2 in a long range. FIG. 10 shows a detached state after fastening. The outer diameter of the tubular body portion 18 is the mandrel head 4
It is preferable that the dimension is such that the progress of the above is prevented and the mandrel reduced diameter portion 7 is reliably broken, for example, the effective diameter of the male screw 6 or more. In addition, the length of the tubular body portion 18 is preferably close to the thickness of the panel 9 so that the tubular portion 18 is surely bited into the panel 10. In this case, if the outer diameter of the tubular portion 18 is formed to be larger than the outer diameter of the male screw 6, it is preferable to make it smaller than the thickness of the panel 9.

FIGS. 11A, 11B, and 11C show some examples of male threads of the body portion 2 of the blind rivet of the second embodiment. The male screw (A) has a larger male screw pitch than that shown in the example of FIG. 8 and improves the biting into the holes of the panel 10. (B)
The male screw has a serrated shape in the chevron shape to further strengthen the force to resist the peeling of the panel 9 and the panel 10 after fastening.
The male screw shown in (C) has a larger pitch than that shown in (B).

12 (A), 12 (B) and 12 (C) show modifications of the groove 8 formed on the flange 3 as a rotating means of the body 2. Of this example, the example of (A) is one in which the plus groove 21 is formed in the flange 3, and the example of (B) is one in which the hexagonal hole 22 is formed in the flange 3.
In the example of (C), the hexagonal nut portion 23 is formed on the flange 3. Of course, the shape is not limited to these shapes, and any other shape can be used as long as the flange can be rotated.

[0014]

According to the blind rivet of the present invention,
A male screw is formed on the outer peripheral surface of the body, and a reduced diameter portion is formed in the vicinity of the enlarged diameter head of the mandrel. Since the flange is provided with means for rotating the body, even if the mating member to be fastened is a soft material,
The expanding head of the mandrel remains inside the body, and the expanding force is strong, and the fastening force is strong, and the force applied in the diameter reducing direction of the body can be sufficiently counteracted. It remains strong, yet it is extremely easy to remove from one side, and it can be easily and strongly reattached.

[Brief description of drawings]

FIG. 1 is a front view of a blind rivet according to a first embodiment of the present invention.

2 is a cross-sectional view of the blind rivet of FIG.

3 is a cross-sectional view after fastening the blind rivet of FIG.

FIG. 4 is a front view showing a state in which the blind rivet of FIG. 1 is removed after being fastened.

FIG. 5 is a cross-sectional view showing a modified example of the use location of the blind rivet in FIG. 1 in a state before fastening.

FIG. 6 is a cross-sectional view showing the blind rivet of FIG. 5 after being fastened.

FIG. 7 is a cross-sectional view showing another example of the use location of the blind rivet in FIG. 1 in a state after fastening.

FIG. 8 is a front view of a blind rivet according to a second embodiment of the present invention.

9 is a cross-sectional view after fastening the blind rivet of FIG.

10 is a front view showing a state in which the blind rivet in FIG. 8 is removed after being fastened.

FIG. 11 is a front view showing a modified example of the male screw of the blind rivet body.

FIG. 12 is a plan view showing a modified example of the rotating means of the flange of the blind rivet of the present invention.

[Explanation of symbols]

 1 Blind rivet 2 Body part 3 Flange 4 Expanding head 5 Mandrel 6 Male screw part 7 Reduced part of mandrel 8 Sliding groove 9, 10 Panel 11 Body part hole 12, 13 Panel hole 15 Mounting member 17 Panel 18 Tube Shaped part 21 Plus groove 22 Hexagonal groove 23 Hexagonal nut part

Claims (1)

[Scope of utility model registration request] 1. A hollow tube-shaped body and a flange formed at one end of the body, and a mandrel housed in the body so that a diameter-expanding head is on the side opposite to the flange. The mandrel shaft extends toward the flange, and the mandrel's expanding head is deformed to expand the body by pulling out the mandrel's shank from the body. In a blind rivet adapted to be fastened to a soft material, a male screw is formed on the outer peripheral surface of the body, and a reduced diameter portion is formed in the mandrel near the enlarged diameter head,
The reduced diameter portion is formed so as to have strength enough to break the mandrel at the reduced diameter portion in the pulling-out operation and leave the expanded diameter head in the body portion, and the flange can rotate the body portion. A blind rivet for soft materials, characterized in that means are provided.