JPH059530Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement of a synthetic resin fastener suitable for connecting other parts, such as another panel, to a panel surface in a polymerized state. In particular, this was devised for the purpose of improving sealing performance by press-fitting a pin so that the head of the grommet elastically comes into close contact with the panel surface.

[Conventional technology] Conventionally, this type of synthetic resin fastener was
Japanese Utility Model Publication No. 44-28336 discloses a grommet that integrally includes a head having an opening, a leg that hangs down from the edge of the opening of the head and has an insertion hole that communicates with the opening, and this grommet. A rivet is known that includes a pin that is inserted into an insertion hole in a leg from an opening in the head of the rivet and expands the outer periphery of the leg radially outward.

[Problems to be solved by the invention] However, in the conventional rivet, when the pin is pushed in, the head tends to warp backwards, which impairs the adhesion between the lower surface of the head and the panel surface, resulting in a seal failure. There were some issues that needed to be improved regarding gender.

[Means for Solving the Problems] Therefore, the present invention is intended to solve the above problems, and the contents thereof will be explained below using embodiments shown in the drawings.

In the present invention, the inner diameter of the opening 4 of the head 5 of the grommet 2 is made smaller than the outer diameter of the pin 3, and the head 5 has an annular inner groove 8 that is open to the upper surface around the opening 4. It is characterized in that an annular outer groove 9 open to the lower surface is formed concentrically.

[Function] If the fastener 1 of the present invention is used to connect, for example, two panels P ₁ and P ₂ in a superposed state,
Mounting holes H ₁ and H ₂ through which the legs 7 of grommet 2 pass are first opened in both panels P ₁ and P ₂ , and then both panels are
After overlapping P ₁ and P ₂ vertically and aligning both the mounting holes H ₁ and H ₂ , insert the legs 7 of the grommet 2 in series into the aligned mounting holes H ₁ and H ₂ , and then insert the pin 3 may be press-fitted from the opening 4 of the head 5 into the insertion hole 6 of the leg 7.

As a result, the outer periphery of the leg portion 7 is connected to the lower panel P ₂
Both panels P _{1 and} P _{2 are sandwiched in an overlapping state between the lower surface of the head 5 which expands in diameter at the bottom and contacts the upper surface of the upper panel P 1 .}

At the same time, since the inner diameter of the opening 4 of the head 5 of the grommet 2 is made smaller than the outer diameter of the pin 3, the inner diameter is expanded by the pin 3, thereby reducing the groove width of the inner groove 8. Therefore, the elastic restoring force of the resin acts to restore the groove width of the inner groove 8 to its original width, and as a result, the lower end of the head 5 on the outside of the outer groove 9 comes into close contact with the top surface of the upper panel _P1 . do.

[Example] The present invention will be described below based on an example shown in the drawings.

In the figure, 1 indicates a fastener, and this fastener 1 consists of a grommet 2 and a pin 3. The grommet 2 and pin 3 are made of thermoplastic resin having appropriate elasticity and rigidity, such as nylon resin. and mold it into separate pieces.

The grommet 2 has an annular head 5 having a circular opening 4 that opens upward and downward in the center, and an insertion hole 6 that hangs down from the edge of the opening 4 of the head 5 and communicates with the opening 4. It is integrally provided with a cylindrical leg portion 7 having a diameter.

Then, the inner diameter of the opening 4 of the head 5 is set to the pin 3.
The head 5 has an annular inner groove 8 around the opening 4 that is open to the upper surface;
An annular outer groove 9, which is slightly larger than the inner groove 8 and open to the lower surface, is formed concentrically. To make the inner diameter of the opening 4 of the head 5 thinner, the inner diameter of the opening 4 is
An annular protrusion 10 integrally protruding from the inner circumferential surface with a semicircular cross section is provided midway along the height of the opening 4, and only the location where this annular protrusion 10 is provided is , the inner diameter of the opening 4 is made smaller than the outer diameter of the pin 3.

In addition, an annular protuberance 11 that protrudes inward is formed in the insertion hole 6 of the leg portion 7 in the middle of its height, and the inner diameter of the insertion hole 6 below the annular protrusion 11 is adjusted to fit the pin 3. Make it thinner than the outer diameter. Note that the tip of the leg portion 7 has a tapered shape to facilitate insertion.

On the other hand, the pin 3 is a cylinder having a substantially hemispherical shape so that its tip 3' can be easily press-fitted. In addition, pin 3
The shape of can be modified in various ways, for example, it may have a flange at the upper end, or may have unevenness along its length.

Next, in order to fix the two panels P ₁ and P 2 in a superposed state using the grommet 2 and pin 3 configured as described above, first attach the legs of the grommet 2 to both panels P ₁ and _{P 2 .} Mounting holes H ₁ and H ₂ large enough for 7 to pass through
(Figure 1). And both panels
Lay P ₁ and P ₂ one above the other and align both mounting holes H ₁ and H ₂ with each other. Then, align the tips of the legs 7 of the grommet 2 with the matching mounting holes H ₁ and H ₂ and insert them in a series, and then align the tip 3' of the pin 3 with the opening 4 of the head 5. , the insertion hole 6 of the leg part 7 from above
Just press it in (Figure 2).

When the pin 3 is press-fitted, its tapered tip 3'
abuts against its annular projection 10 in the opening 4 of the head 5. Now, when the pin 3 is pushed in strongly, since the inner diameter of the opening 4 is narrowed by the annular protrusion 10, the pin 3 cuts in and the annular protrusion 10 is pushed outward in the radial direction. It is pushed, passes through the inner diameter of the opening 4 while expanding, and reaches the insertion hole 6 of the leg portion 7 .

Here, too, since the inner diameter of the insertion hole 6 of the leg 7 is narrowed by the annular protrusion 11, the tapered tip of the pin 3 is attached to the upwardly tapered surface 11' that reaches the annular protrusion 11. 3' comes into contact first, and the pin 3 cuts in to push the annular protuberance 11 radially outward, so that the outer periphery of the leg 7 gradually expands in diameter under the lower panel _P2 . Then, at the position where the outer circumferential surface of the pin 3 abuts the annular raised portion 11, the outer circumference of the leg portion 7 expands to its maximum diameter, and the outer circumference of the leg portion 7 expands in diameter to the maximum, and the outer circumference of the leg portion ₇ expands in diameter to the maximum between it and the lower surface of the head portion 5 that abuts the upper surface of the upper panel P1. Both panels P ₁ and P ₂ are sandwiched in a superposed state. (Figure 3).

At the same time, in the opening 4 of the head 5, the annular protrusion 10 contacts the outer peripheral surface of the pin 3 and is pushed outward in the radial direction by the pin 3, so that the inner wall a of the inner groove 8 The outer periphery is expanded in diameter, and the groove width of the inner groove 8 is decreased. On the other hand, the inner wall a of the inner groove 8 and the intermediate wall b between the outer groove 9 which faces each other with the inner groove 8 in between are connected to each other at the bottom by an annular lower connecting part c over the entire circumference. Since it is connected, the lower connecting part c
The elastic restoring force generates a force that presses the intermediate wall b downward toward the upper surface of the panel _P1 using the lower connecting portion c as a fulcrum.

On the other hand, both the intermediate wall b and the outer wall d, which face each other with the outer groove 9 in between, have an annular upper connecting portion e extending over the entire circumference.
Since they are connected to each other at the top, when a downward force is applied to the intermediate wall b, this force causes
The lower end of the outer wall d is pressed against and in close contact with the upper surface of the upper panel _P1 .

Also, when the lower end of the outer wall d is pressed against the upper surface of the panel P ₁ , the outer wall d opens radially outward using the upper connecting portion e as a fulcrum, and the lower end of the outer wall d is pressed against the upper surface of the panel P ₁ .
The elastic restoring force of the upper connecting portion e acts against this force. Therefore, a restoring force acts to pull the outer wall d back inward in the radial direction, preventing the outer wall d from opening outward in the radial direction, and the contact angle between the lower end of the outer wall d and the upper surface of the panel P ₁ is maintained vertically, and the lower end of the outer wall d is surely in close contact with the upper surface of the panel _P1 .

FIG. 4 shows another embodiment of the present invention, in which the grommet 2 and pin 3 are integrally molded.

That is, the pin 3 is inserted into the opening 4 of the head 5 of the grommet 2.
The grommet 2 and the pin 3 are integrally molded with the head 5 and the pin 3 connected by a thin annular connecting part 12 with the tip 3' of the grommet inserted shallowly.
The legs 7 of the grommet 2 integrally formed in this way are
Insert into the mounting holes H ₁ , H ₂ of both aligned panels P ₁ , P ₂ and drive the upper end of the pin 3 that protrudes upward from the head 5 of the grommet 2 downward.
A shearing force acts on the pin 2, causing it to break into pieces, and the pin 3 enters the insertion hole 6 of the leg 7.

According to this embodiment, handling of the grommet 2 and pin 3 can be simplified.

In the embodiment shown in the drawings, the fastener 1 is used as a rivet to connect two panels P ₁ and P ₂ in a superposed state. However, the shape of the head 5 of the grommet 2 can be changed to By transforming it into , it can be used for other purposes. For example, the head 5 of the grommet 2 may be deformed into the shape of a molding clip, which may be fixed to the body panel of an automobile, and a bracket for fixing the molding may be connected to the fixed molding clip.

[Effects of the invention] As explained above, according to the invention, the lower surface of the grommet head elastically comes into close contact with the panel surface by press-fitting the pin, so it is possible to use a synthetic resin fastener with excellent sealing properties. can be provided.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and Fig. 1 is a partially cutaway perspective view showing the grommet, pin, and both panels, and Fig. 2 is a sectional view showing the installation procedure with the pin inserted shallowly. , FIG. 3 is a sectional view showing a state in which both panels are connected and fixed, and FIG. 4 is a longitudinal sectional view showing another embodiment. 1... Fastener, 2... Grommet, 3... Pin, _P1 , _P2 ...Panel, _H1 , _H2 ...Mounting hole, 4
... opening, 5 ... head, 6 ... insertion hole, 7 ... leg, 8 ... inner groove, 9 ... outer groove.

Claims (1)

[Claims for Utility Model Registration] A grommet that integrally includes a head having an opening, a leg that hangs down from the edge of the opening of the head and has an insertion hole that communicates with the opening; Insert from the opening in the head into the insertion hole in the leg,
A synthetic resin fastener comprising a pin that expands the outer periphery of the leg radially outward, wherein the inner diameter of the opening of the head of the grommet is smaller than the outer diameter of the pin, and the head has: A synthetic resin fastener characterized by concentrically forming an annular inner groove that is open to the upper surface around the opening and an annular outer groove that is one size larger than the inner groove and is open to the lower surface.