JPS6332407Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a synthetic resin rivet that is mainly used for riveting thin plates. Regarding synthetic resin rivets.

[Conventional technology]

Conventionally, synthetic resin rivets that can be riveted simply by press-fitting into the rivet area have been formed with a diamond-shaped bulge at the bottom of the body, and a diamond-shaped hole is formed in this diamond-shaped portion to allow for greater elastic deformation. A so-called canoe-shaped rivet is known, and when the rivet is press-fitted into the hole where the rivet is to be riveted, the diamond-shaped portion undergoes a large elastic deformation due to the force exerted on the side of the tip of the body rather than the inner wall of the hole, resulting in a diameter reduction. In this way, insertion of the lower part of the body is achieved, and after insertion, the diamond-shaped portion naturally returns elastically and expands in diameter, and as a result, the rivet itself is prevented from coming off.

[Problem that the invention attempts to solve]

However, the so-called canoe-type rivet described above has the following problems.

Because it is necessary to form a diamond-shaped hole in the lower part of the body, the diameter of the body cannot be made small, and it is impossible to rivet into a small-diameter hole.

Since a diamond-shaped hole is provided in the diamond-shaped portion of the lower part of the body, stress concentration in the axial direction occurs at the edge of the diamond-shaped hole, leading to a decrease in the proof strength of the rivet.

Since the lower part of the body is formed to bulge out in a diamond shape, the lower part of the body is crimped to the inner wall of the hole where the rivets are to be attached. Since a gap larger than the dimensional tolerance remains between the inner wall of the head and the inner wall of the head, rattling is likely to occur on the head side.

[Purpose of invention]

The purpose of this invention is to solve the above-mentioned problems.It is possible to rivet even small-diameter holes, has a wide range of applications, has high axial tightening strength, and eliminates looseness after riveting. The purpose of the present invention is to provide a synthetic resin rivet that is free of .

[Means for solving problems]

In order to achieve the above object, the synthetic resin rivet according to the present invention has a structure that has viscoelasticity and includes a first protrusion having a chevron-shaped cross section in the axial direction on one side of the lower part of the body.
The second protrusion has a downwardly inclined surface formed at a position near the head on the substantially opposite side thereof.

〔Example〕

Next, one embodiment of the present invention will be described based on the accompanying drawings.

FIG. 1 is a front view showing an embodiment of a synthetic resin rivet according to the present invention.

FIG. 2 is a bottom view showing the same embodiment.

FIG. 3 is a longitudinal sectional view showing the same embodiment.

In the figure, reference numeral 1 indicates a synthetic resin rivet according to the embodiment, which includes a pan-shaped head 2, a substantially cylindrical body 3, and this body 3.
It is generally composed of a first protrusion 4 on one side of the lower portion, and a second protrusion 5 on the opposite side near the head 2. This synthetic resin rivet 1 is an integrally molded product of viscoelastic synthetic resin (eg, nylon 66, Delrin, etc.).

An annular recess 2a is provided on the lower surface of the head 2, which is formed with a pan-shaped enlarged diameter (see Fig. 3). 2b is formed, and an annular protrusion 2c is formed on the outside thereof.

The cross-sectional shape of the body portion 3 is as shown in FIG.
It has an elliptical shape with a short axis in the direction of the protrusion 4 and the second protrusion 5. A tapered portion 3a is provided at the distal end of the body portion 3 in order to facilitate insertion into the hole at the location to be riveted.

A first protrusion 4 having a substantially chevron-shaped axial cross section is integrally formed on one side of the body 3 at a position slightly above the tapered portion 3a and below the body portion 3. This first protrusion 4
has approximately semi-elliptical surfaces 4c formed on both the upper and lower sides.

With respect to this first protrusion 4, the substantially opposite side thereof (approximately
180 degrees) near the head 2 position (first protrusion 4 and head 2)
A second protrusion 5 is integrally formed at an intermediate position between
It consists of a substantially semi-elliptic tapered surface 5b having a substantially semi-elliptic shape, a substantially semi-elliptic surface 5c, and an upright surface 5d facing the lower surface of the head 2. This approximately semi-elliptic tapered surface 5b and the upright surface 5
The ridgeline portion formed by d forms an edge 5e having a substantially right-angled cross section.

Next, to explain how the above embodiment is used, first, as shown in FIG. 4A, the upper plate 6a and the lower plate 6b are
A rivet 1 is attached to the hole 6c at the riveted location consisting of
When the tip of the rivet 1 is press-fitted, the tapered surface 4a near the tip of the first protrusion 4 comes into contact with the hole edge of the upper plate 6a, and the rivet 1 is slightly tilted to the right in the figure. Rivet 1 in this state
When pressed further, the first protrusion 4 is elastically deformed and the hole edge portion passes over the tapered surface 4a, and the fourth
As shown in FIG. B, the rivet 1 is inserted into the hole 6c in an upright state, with the substantially semi-elliptical surface 4c in close contact with the hole wall under compression and deformation. When the press-fitting operation is continued further, the first protrusion 4 is inserted into the lower plate 6 as shown in FIG. 4C.
As it reaches the vicinity of the opening of the hole 6c in b, the approximately semi-elliptical tapered surface 5b of the second protrusion 5 is elastically deformed and comes into contact with the right side hole edge portion in the figure, so that the right side hole edge portion in the figure relatively The rivet 1 elastically rides up on the inclined surface 5a of the semi-elliptic tapered surface 5b, and due to the reaction force, the rivet 1 is inserted while being bent into a dogleg shape. When it is press-fitted further, the substantially semi-elliptical surface 4c of the first protrusion 4 appears outside the lower plate 6b, as shown in FIG. 4D. Rivet 1
The body 3 is elastically bent into a dogleg shape by the reaction force from the second protrusion 5, and its contact portion is connected to the hole 6c.
pushing the wall outward. The approximately semi-elliptic tapered surface 4b of the first protrusion 4 near the head 2 abuts and is locked to the right side hole edge portion of the lower plate 6b in the figure.

Fixation to the upper plate 6a and lower plate 6b in this state is performed by the head 2, the first protrusion 4, the second protrusion 5, and the bent portion of the bent body 3. Lower plate 6b
The cross-sectional area of the part that clamps the rivet is the sum of the cross-sectional area of the body 3 and the cross-sectional area of the first protrusion 4 formed by bulging therein, and since there is no hole in the body, the axis of the rivet 1 The directional strength is stronger than conventional products. Since the second protrusion 5 and the bent body 3 are elastically press-fitted into the hole 6c, lateral wobbling is completely absorbed. Since the rivets are attached by bending the body 3 as the second protrusion 5 is press-fitted, the shaft diameter can be made smaller than in the past, and it can be applied to locations with small hole diameters. .

Note that the first protrusion 4 and the second protrusion 5 are not only bulged into a substantially semi-elliptical shape as shown in FIG. It may also be configured in a straight line.

[Effect of idea]

As explained above, the synthetic resin rivet according to the present invention provides the following effects.

There is no hole in the body, and the area that clamps the lower plate is the sum of the cross-sectional area of the body and the cross-sectional area of the first protrusion, so the axial strength is higher than that of conventional rivets. It is large and can prevent a decline in yield strength due to stress concentration.

As the second protrusion is press-fitted into the hole, the body itself bends due to its viscoelasticity, and as these protrusions expand and adhere tightly to the hole wall, horizontal wobbling of the riveted material is completely eliminated. It can be removed quickly and fatigue failure can be prevented.

Further, when the first protrusion is configured with tapers formed on both the upper and lower sides, the press-fitting operation can be performed smoothly.

Furthermore, when an edge is formed on the upper side of the second protrusion, the edge increases the locking force against the hole wall of the upper plate, so that it is possible to increase the vertical clamping force against the material to be riveted. can.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of a synthetic resin rivet according to the present invention. FIG. 2 is a bottom view showing the same embodiment. FIG. 3 is a longitudinal sectional view showing the same embodiment. Figure 4 A, B, C, D are
FIG. 6 is a vertical cross-sectional view showing how the same embodiment is used. 1... Synthetic resin rivet, 2... Head, 2a
...Annular recessed portion, 2b... Chamfer, 2c... Annular convex stripe, 3... Body, 3a... Tapered portion, 4... First
Protrusions, 4a, 4b...approximately semi-elliptical tapered surface of the first protrusion, 4c...approximately semi-elliptic surface of the first protrusion, 5...second protrusion, 5a...second protrusion 5b...Approximately semi-elliptical tapered surface of the second protrusion, 5c... Approximately semi-elliptical surface of the second protrusion, 5d... Upright surface of the second protrusion, 5e
...Edge of second protrusion, 6a...Top plate, 6b...
Lower plate, 6c...hole for the riveted area.

Claims (1)

[Claims for Utility Model Registration] (1) A first protrusion with a mountain-shaped axial cross section on one side of the lower part of the torso, and a second protrusion with a downwardly inclined surface formed near the head on the substantially opposite side. 1. A viscoelastic synthetic resin rivet comprising a protrusion. (2) The synthetic resin rivet according to claim (1), wherein the first protrusion includes a taper formed on both the upper and lower sides. (3) Utility model registration claim No. (1) characterized in that the second protrusion has an edge on the upper side.
Synthetic resin rivets as described in paragraph or paragraph (2).