JP2006118672A - Combined type resin rivet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combined type resin rivet capable of stably providing high fastening strength, capable of corresponding to multiple types of work thickness by rivets with the same axial length, preventing a positional deviation of a work and a backlash between a rivet shaft and the work after fastening, and allowing simple caulking by a hammer or the like. <P>SOLUTION: The combined type resin rivet is comprised by a male rivet and a female rivet made of synthetic resin having a head and a leg, and they are integrated by fitting the leg of the male rivet in the hollow leg of the female rivet. The combined type resin rivet is comprised by forming a circumferential groove on a leg inner face of the female rivet, and forming a circumferential rib on a leg outer face of the male rivet, and the groove and the rib are interlocked by pressing the male rivet leg into the female rivet leg. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a combination type rivet composed of a male rivet and a female rivet, and more particularly relates to a combination type rivet made of a synthetic resin that has excellent fastening strength and can cope with workpieces of various thicknesses.

Conventionally, rivets have been widely used as connecting parts for easily and firmly connecting a plurality of workpieces, and of course, metal workpieces can be bonded to each other as well as non-metal made of cloth, paper, plastic, etc. It is also widely used for joining workpieces, and there are various types of rivets depending on the materials and properties of the workpieces to be joined.
Among these, the combination type rivet composed of male rivets and female rivets has a good appearance after being fastened, and thus is particularly suitably used for a bag or the like that requires a good appearance.

As a technique related to such a combination type rivet, for example, there is a disclosed technique disclosed in Patent Document 1 previously filed by the applicant of the present application.
The technology disclosed in Patent Document 1 has problems with products that are fastened with conventional metal rivets, specifically, it is difficult to separate and dispose of cloth products and paper products fastened with metal rivets. It was created in view of the problem of being, and both male and female rivets were made of synthetic resin.

The specific structure of the rivet disclosed in Patent Document 1 is that the leg portions of the male rivet and the female rivet are formed in a hollow cylindrical shape, and the inner diameter of the leg portion of the female rivet is increased in a tapered shape toward the tip. The outer diameter of the leg end of the male rivet is substantially the same.
According to this rivet, the male and female rivets can be coupled using the elastic deformation of the rivet legs to fasten the workpieces, but there is a problem that the fastening strength is greatly inferior compared to a normal metal rivet. there were.
Also, if the workpiece to be fastened is thicker than the axial length of the female rivet, there will be a gap between the lower surface of the head of the male rivet and the front end surface of the leg of the female rivet. In the case of a product having a thin work (paper or the like) such as a calendar, there is a problem that the work is displaced due to the work entering the gap.
Furthermore, since it is difficult to obtain the dimensional accuracy of the fitting part between the male rivet and the female rivet, the fastening strength is likely to vary, and the rivet shaft and the work are not easily rattled, and simple caulking with a hammer or the like is difficult. There was.

Further, the applicant of the present application has proposed a resin rivet in Patent Document 2 that prevents loosening of caulking over time, which is a drawback of resin rivets, and can maintain high fastening strength.
The resin rivet disclosed in Patent Document 2 is configured to be wound and fastened so that the inner surface of the tip end portion of the leg comes into contact with the workpiece at the time of normal temperature caulking, compared with a conventional resin rivet. Thus, a high fastening strength can be obtained.
However, this resin rivet cannot be denied that the fastening strength is greatly inferior to that of a normal metal rivet. Moreover, although this resin rivet can obtain a higher fastening strength than a conventional resin rivet, it cannot be used in places where appearance is required due to its poor appearance after fastening.

Utility Model Registration No. 3066832 Japanese Patent No. 3029826

  The present invention has been made to solve the above-mentioned problems of the prior art, can stably obtain a high fastening strength, and can cope with various kinds of workpiece thicknesses with rivets having the same axial length, It is an object of the present invention to provide a combination type resin rivet that is free from positional displacement of the workpiece after fastening or rattling between the rivet shaft and the workpiece and that can be easily caulked with a hammer or the like.

  The invention according to claim 1 comprises a male rivet and a female rivet made of synthetic resin having a head and a leg, and the leg of the male rivet is fitted into the hollow leg of the female rivet to integrate them. A combination type rivet, wherein a circumferential groove is formed on the inner surface of the leg of the female rivet, and a circumferential rib is formed on the outer surface of the leg of the male rivet. The present invention relates to a combination type resin rivet characterized by being engaged by press-fitting male rivet legs into the part.

  According to a second aspect of the present invention, the inner surface of the leg portion of the female rivet is provided with a grooved portion having the circumferential groove at the base end portion and a grooveless portion without the circumferential groove at the distal end portion. The inner diameter of the grooveless portion is larger than the inner diameter of the grooved portion, and the male rivet has an outer diameter of the head that gradually becomes smaller toward the leg portion, and the inner diameter of the grooveless portion is the head. 2. The combination type resin rivet according to claim 1, wherein the combination type resin rivet is smaller than the maximum diameter of the portion and larger than the minimum diameter.

The invention according to claim 3 relates to the combination type resin rivet according to claim 1 or 2, wherein the outer diameter of the rib is larger than the inner diameter of the groove.
According to a fourth aspect of the present invention, there is provided a combined resin rivet according to any one of the first to third aspects, wherein a through-hole penetrating toward the hollow leg portion is provided in the head of the female rivet. About.

The invention according to claim 5 is characterized in that the groove forms a female screw, the rib forms a male screw, and a groove or hole in which a driver or a wrench can be engaged is provided in the head of the male rivet. The combination type resin rivet according to any one of claims 1 to 4.
The invention according to claim 6 relates to the combination type resin rivet according to any one of claims 1 to 5, wherein a center hole is provided in the head of the male rivet.

According to the invention of claim 1, since the groove and the rib mesh with each other by press-fitting the leg of the male rivet into the leg of the female rivet, this meshing exerts an action of preventing the pulling in the pulling direction and is fastened. Is difficult to separate, and a high fastening strength can be obtained. Moreover, it is possible to easily caulk with only a hammer.
In addition, by utilizing the engagement between the groove and the rib, high fitting strength can be stably exhibited without requiring high dimensional accuracy in the fitting portion.

According to the invention of claim 2, since the head of the male rivet enters the leg of the female rivet during fastening, there is no gap between the lower surface of the head of the male rivet and the front end surface of the leg of the female rivet. There is no position shift of the fastened workpiece.
In addition, the leg of the female rivet is curled and enlarged by the head of the male rivet when fastened, and the head of the male rivet functions as a plug that prevents the curled part from returning, so the curl diameter is unlikely to shrink. High fastening strength can be obtained.
In addition, since the curl portion does not easily return, high fastening strength can be obtained without increasing the curl diameter. Therefore, even if the thickness of the workpiece to be fastened is slightly increased or decreased compared to the axial length of the rivet, the fluctuation of the fastening strength can be suppressed to be small, and a single shaft length of rivet can be used for various types of workpieces. it can.

According to the invention of claim 3, the outer diameter of the rib is set larger than the inner diameter of the groove, so that the leg of the female rivet expands when the male rivet leg is press-fitted into the leg of the female rivet. In addition, it is possible to suppress the rattling between the work and the rivet shaft.
According to the invention of claim 4, the through-hole penetrating toward the hollow leg portion is provided in the head of the female rivet so that the male rivet can be inserted through the through-hole of the female rivet after fastening. A force can be applied to the tip of the leg so that both rivets can be easily separated.

According to the invention of claim 5, after completion of the fastening, the male rivet can be easily separated from the female rivet by engaging and rotating the screwdriver or wrench in the groove or hole provided in the head of the male rivet. It becomes possible to do.
According to the invention of claim 6, since the center hole is provided in the head of the male rivet, when the caulking operation is performed using the automatic rivet caulking machine, the tip of the guide pin of the caulking machine is moved to the center hole. It is possible to perform centering by inserting it into the head, and it is possible to efficiently perform a highly accurate and stable caulking operation by an automatic rivet caulking machine.

Hereinafter, preferred embodiments of a combination type resin rivet according to the present invention will be described with reference to the drawings.
FIG. 1 is a view showing an example of an embodiment of a combination type resin rivet according to the present invention, in which (a) shows a female rivet and (b) shows a male rivet.
In the present invention, the male rivet and the female rivet are both formed entirely from a synthetic resin.
Examples of the synthetic resin include, but are not limited to, polyacetal resin, polyethylene resin, polypropylene resin, nylon resin, polybutylene terephthalate resin, and the like.
Among the resins exemplified above, polyacetal resin is most preferably used because it has appropriate flexibility and mechanical strength.

The female rivet (1) is composed of a head (2) and a leg (3).
The head (2) has a spherical upper surface and an annular groove (4) formed on the lower surface. (In FIG. 1A, the left direction corresponds to the upward direction of the female rivet, and the right direction corresponds to the downward direction of the female rivet.)
The leg portion (3) has a hollow cylindrical shape opened at the tip, and has a grooved portion (6) having a circumferential groove (5) formed on the inner surface and a circumferential groove. Has no groove (7).

The grooved part (6) is formed on the base end side (upper side) of the leg part (3), and the grooveless part (7) is formed on the distal end side (lower side) of the leg part (3). The inner diameter of the non-portion (7) is formed larger than the inner diameter of the grooved portion (6).
The ratio of the length of the grooved part (6) and the non-grooved part (7) is set, for example, in the range of 6: 4 to 4: 6, but is not particularly limited to this range.

The specific form of the circumferential groove (5) is not particularly limited, and a plurality of ring-shaped grooves may be formed at intervals, and one or a plurality of spiral grooves may be formed from the distal end side to the proximal end. You may form continuously toward the side.
The number of circumferential grooves (5) appearing along a line parallel to the central axis of the grooved part (6) can be arbitrarily set according to the length of the leg part (3) and is particularly limited. The number is not limited to one or plural, but preferably plural.
The number of the circumferential grooves (5) is preferably the same as the number of ribs appearing along a line parallel to the central axis of the male rivet (11) described later.
The specific number is preferably 3 or more, more preferably 5 or more. This is because the greater the number of grooves, the greater the meshing with the ribs of the male rivet (11), so that the function of retaining is effectively exhibited.

The male rivet (11) is composed of a head (12) and a leg (13).
The head (12) has a spherical upper surface, and the lower surface is rounded so that its outer diameter gradually decreases toward the leg. (In FIG. 1B, the right direction corresponds to the upward direction of the male rivet and the left direction corresponds to the downward direction of the male rivet.)
The inner diameter of the groove-free portion (7) of the female rivet (1) is smaller than the maximum diameter of the head (12) and greater than or equal to the minimum diameter.

The leg portion (13) is a substantially cylindrical solid body, and a circumferential rib (14) is formed on the outer surface thereof.
The specific form of the circumferential rib (14) is not particularly limited, and a plurality of ring-shaped ribs may be formed at intervals, and one or a plurality of spiral ribs may be formed from the proximal end to the distal end. You may form continuously toward the side.
The number of circumferential ribs (14) appearing along a line parallel to the central axis of the leg (13) can be arbitrarily set according to the length of the leg (13), and is not particularly limited. The number is one or a plurality, preferably a plurality.
Preferably, as described above, the number is the same as the number of grooves appearing along a line parallel to the central axis of the female rivet (1), specifically, it is preferably 3 or more, more preferably 5 It is said above.

The outer diameter of the circumferential rib (14) of the male rivet (11) is set slightly larger (for example, about 0.1 mm) than the outer diameter of the circumferential groove (5) of the female rivet (1). .
The circumferential groove (5) of the female rivet (1) and the circumferential rib (14) of the male rivet (11) are connected to the leg (13) of the male rivet (11) by the leg of the female rivet (1). (3) When press-fitted into the legs, the legs of the female rivet are elastically deformed and expanded, so that they can be engaged with each other.
At the time of this engagement, the leg part (3) of the female rivet (1) is expanded by the leg part (13) of the male rivet (11) and its outer diameter expands.

The overall length of the male rivet (11) is set shorter than the length of the leg (3) of the female rivet (1).
The length of the leg part (13) of the male rivet (11) is set to be the same as or slightly shorter than the length of the grooved part (6) of the leg part (3) of the female rivet (1). The length (thickness) of the head (12) of the male rivet (11) is shorter than the length of the groove-free portion (7) of the leg (3) of the female rivet (1), preferably 2 minutes. Is set to a length of about 1.

FIGS. 2A and 2B are diagrams showing a usage state of the combination type resin rivet according to the present invention, in which FIG. 2A is an initial state of coupling of male rivets and female rivets, and FIG. 2B is a completed state of coupling of male rivets and female rivets. Respectively.
When the workpiece is fastened using the combination type resin rivet according to the present invention, first, the leg portion (3) of the female rivet (1) is inserted into the through hole formed in the workpiece, and is shown in FIG. As shown, the leg (13) of the male rivet (11) is press-fitted into the leg (3) of the female rivet (1), and the rib (14) at the tip is engaged with the groove (4).
The press-fitting of the male rivet (11) into the female rivet (1) can be performed manually using a hammer or the like, or can be performed automatically using a rivet caulking machine.

  In this initial state where the rib (14) and the groove (4) are only partially engaged, the leg (3) of the female rivet (1) expands slightly, but the head of the male rivet (11) ( In 12), only the lower end portion is inserted into the leg portion (3) of the female rivet (1), so that no outward curl deformation occurs.

When the male rivet (11) is further press-fitted from the state of FIG. 2 (a), the rib (14) of the male rivet (11) meshes with the groove (4) of the female rivet (1) one after another and the female rivet (1 ) Is further expanded, and at the same time, the head (12) of the male rivet (11) expands the tip of the leg (3) of the female rivet (1) while expanding the outer diameter. At this time, the tip of the leg (3) that is spread out is curled well by the round formed on the lower surface (back surface) of the head (12).
Then, as shown in FIG. 2B, when the lower surface of the head (12) of the male rivet (11) reaches the base end of the groove-free portion (7) of the female rivet (1), the male rivet (11 The entire leg portion (13) is housed in the grooved portion (6), and the curl deformation at the tip of the leg portion (3) of the female rivet (1) is finished, and the fastening of the workpiece is completed.

In this fastening completion state, all of the rib (14) formed on the leg (13) of the male rivet (11) and the groove (4) formed on the leg (3) of the female rivet (1) Since the meshed state is achieved, the retaining function in the pulling direction is greatly exhibited, and high fastening strength can be obtained.
Moreover, since the leg part (3) of the female rivet (1) expands and comes into close contact with the inner surface of the through hole of the work, it is possible to suppress the rattling between the work and the rivet shaft.

Furthermore, since the head (12) of the male rivet (11) exhibits the function of a plug that prevents the curled portion from returning, the curl diameter is less likely to be reduced, and high fastening strength can be maintained over a long period of time. . In addition, since the curl diameter is not easily reduced, a high fastening strength can be obtained without increasing the curl diameter. Therefore, variation in fastening strength due to increase / decrease in the thickness of the work to be fastened is reduced, and a single rivet with a single shaft length can be used. It can handle workpieces of various thicknesses.
In addition, since the work is fastened with the head (12) of the male rivet (11) entering the leg (3) of the female rivet (1), the lower surface of the head of the male rivet and the legs of the female rivet are fastened. There is no gap between the front end surface of the part and the position of the fastened workpiece does not shift.

Moreover, in this invention, as shown in FIG. 3, the structure which provides the through-hole (8) penetrated toward a hollow leg part (3) in the head (2) of a female rivet (1) is employ | adopted. You can also.
When such a configuration is adopted, after the fastening is completed, a thin rod-like object such as a driver's tip is inserted into the through hole (8) of the female rivet (1), and the tip of the leg (13) of the male rivet (11). , It is possible to easily separate the combined rivets.

Furthermore, in this invention, as shown in FIG. 4, the structure which provides the groove | channel (15) or hole which can engage a driver or a wrench in the head (12) of a male rivet (11) is also employable.
Specifically, as the groove (15), a minus groove that can be engaged with a minus driver, a plus groove that can be engaged with a plus driver, and the like can be provided. A square hole can be provided.
When such a configuration is adopted, the circumferential groove (5) of the female rivet (1) and the circumferential rib (14) of the male rivet (11) are formed in a female screw and a male screw that can be screwed together. Then, after the fastening is completed, the male rivet can be easily separated from the female rivet by engaging and rotating a screwdriver or a wrench in a groove or hole provided in the head of the male rivet.

Furthermore, in this invention, as shown in FIG. 5, the structure which provides a center hole (16) in the head (12) of a male rivet (11) is also employable.
When this configuration is adopted, the tip of the guide pin of the automatic rivet caulking machine can be inserted into the center hole (16) for centering, and high-accuracy and stable caulking work with the automatic rivet caulking machine can be performed efficiently. Can be done.

Hereinafter, the effects of the present invention will be made clearer by showing examples and comparative examples of the combination type resin rivet according to the present invention. However, the present invention is not limited to the following examples.
1. Example Sample A combination type resin rivet (material: polyacetal resin) having the shape shown in FIG. 1 was used as a sample of an example of the present invention.
The dimensions of the female rivet are as follows: leg outer diameter: φ5 mm, inner diameter of the grooved part of the leg (diameter of circumferential groove): φ2.5 mm, inner diameter of the part without the leg groove: φ3.5 mm, total length: 10 mm, leg length The length of the male rivet is: leg outer diameter (circumferential rib diameter): φ2.6 mm, total length: 5.75 mm, leg length: 4 mm, head maximum diameter: φ5 mm, head minimum diameter : Φ3.5 mm.

2. Comparative Example 1 Sample As a sample of Comparative Example 1, a normal hollow rivet (material: aluminum, leg outer diameter: φ5 mm, leg length: 7 mm) which is not a combination rivet was used.
3. Comparative Example 2 Sample As a sample of Comparative Example 2, a hollow rivet (material: polyacetal resin, leg outer diameter: φ5 mm, leg length: 7 mm) disclosed in Patent Document 2 which is not a combination rivet was used.

4). Tensile strength test Two rivets are crimped and fastened using the rivets of Examples and Comparative Examples 1 and 2 above, the two fastened workpieces are pulled in opposite directions, and the tensile force when the workpieces are completely separated from each other Was measured. Three samples were prepared for each of the example and the comparative examples 1 and 2, and the test was performed three times in total.
The test results are shown in Table 1 below. In addition, about the comparative example, only the average value of a measured value is shown, and about the Example, the average value and the measured value of each time are shown together.

As can be seen from the results in Table 1, the resin rivet of Comparative Example 2 provided only a fastening strength as low as about 24% of the metal rivet of Comparative Example 1, but the rivet of the Example had all three samples. A high fastening strength of 50% or more of the metal rivet of Comparative Example 1 was stably obtained.
From this result, it was confirmed that the rivet according to the example, that is, the rivet according to the present invention can stably obtain a fastening strength as high as 50% or more of a normal metal rivet, which is twice or more that of a conventional resin rivet.

  The rivet according to the present invention is suitably used for fastening a workpiece made of plastic, paper, or the like, and is preferably used for a thick sample book (a large number of mounts) requiring high fastening strength.

It is a figure which shows an example of embodiment of the combination-type resin rivet which concerns on this invention, Comprising: (a) shows a female rivet, (b) shows a male rivet. It is a figure which shows the use condition of the combination type resin rivet which concerns on this invention, Comprising: (a) shows the initial state of the coupling | bonding of a male rivet and a female rivet, (b) shows the completion state of the coupling | bonding of a male rivet and a female rivet, respectively. ing. It is sectional drawing which shows the example of a change of the female rivet which concerns on this invention. It is a side view which shows the example of a change of the male rivet which concerns on this invention. It is a side view which shows the example of a change of the male rivet which concerns on this invention.

Explanation of symbols

1 female rivet 2 head 3 leg 4 annular groove 5 circumferential groove 6 grooved part 7 grooveless part 8 through hole 11 male rivet 12 head 13 leg 14 circumferential rib 15 groove (or hole)
16 Center hole

Claims (6)

  A combination type rivet comprising a male rivet and a female rivet made of synthetic resin having a head and a leg, wherein the leg of the male rivet is fitted into the hollow leg of the female rivet, and both are integrated. A circumferential groove is formed on the inner surface of the leg portion of the female rivet, and a circumferential rib is formed on the outer surface of the leg portion of the male rivet, and the groove and the rib are formed on the male rivet leg portion into the female rivet leg portion. Combination type resin rivet characterized by being engaged by press fitting.   On the inner surface of the leg portion of the female rivet, a grooved portion having the circumferential groove is provided at the base end portion, and a grooveless portion not having the circumferential groove is provided at the distal end portion, and the inner diameter of the grooveless portion is The male rivet is made larger than the inner diameter of the grooved portion, the outer diameter of the head gradually decreases toward the leg portion, and the inner diameter of the non-grooved portion is smaller than the maximum diameter of the head and 2. The combination type resin rivet according to claim 1, wherein the combination type resin rivet has a minimum diameter or more.   3. The combination type resin rivet according to claim 1, wherein an outer diameter of the rib is larger than an inner diameter of the groove.   The combined resin rivet according to any one of claims 1 to 3, wherein a through-hole penetrating toward the hollow leg portion is provided in a head portion of the female rivet.   5. The structure according to claim 1, wherein the groove forms a female screw, the rib forms a male screw, and a groove or a hole into which a driver or a wrench can be engaged is provided in the head of the male rivet. Combination type resin rivet according to crab. 6. The combination type resin rivet according to claim 1, wherein a center hole is provided in a head portion of the male rivet.

Images