JPS6037452Y2 - Plastic studs with rivets - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stud with a rivet that is attached to a mounting hole with only one side operation and is provided with an article-engaging head that locks an article.

Conventionally, when attaching a decorative molding to the body of a car, the method disclosed in Japanese Patent Publication No. 16886/1986 was used, that is, first, a steel stud (button) was welded to the desired position of a single piece, and then a plastic stud was attached to it. A method often used is to cover the metal adapter with a metal molding and fit a metal molding over it.

According to the description in this publication, the problem of corrosion that was unavoidable with the previous drilling method is eliminated.

However, in reality, the material of the stud welds tends to corrode, so it may not be possible to maintain watertightness after all, and even if this is not a long-term problem, various equipment for welding the studs is required. Moreover, since the stud itself is made of metal, it is costly and the installation work is not easy.

The present proposal is based on the above, and consists of a plastic rivet or stud that can be easily attached to the mounting hole by only one side operation and pulling up the shaft rod. Provides a stud with a rivet that is provided with an engagement head to reduce costs and facilitate manufacturing and installation, and also ensures watertightness and makes it easy to obtain watertightness because the rivet head covers the edge of the mounting hole and comes into close contact with the rivet. This is what I am trying to do.

This also solves the problem of corrosion of the stud itself.

This project also replaces conventional plastic deformation type metal blinds.
In place of rivets, plastic materials with excellent characteristics such as ease of molding, rust prevention, and low cost can be used. In other words, we have developed a unique device that allows the blind rivet function to be satisfied even through elastic deformation. It is also possible to provide a rivet with a structure, provide a suction cup-like rivet head for watertightness, and further provide an article-engaging head on the rivet.

Hereinafter, one embodiment of the present invention will be described in detail. In this embodiment as well, the stud with the rivet of the present invention is made of plastic,
In FIG. 2, a chain expansion shaft 20 is fitted into the hollow stud 10 shown in cross section.

In this case, the hollow stud 10 is a chain body 1 provided with four grooves 13.
4, a flange-like rivet head 11 provided at its upper end, and an article-engaging head 12 extending further above and terminating in an enlarged flange.

In this embodiment, the rivet head 11 is in the shape of a suction cup, which is an optimal shape for achieving watertightness as will be described later.

The shaft rod 20 is fitted into the hollow stud 10 and engaged or fixed near the lower part of the chain body 14. In this case, the lower end of the shaft rod 20 has a T-shaped protrusion 21, which is attached to the chain body 14. It fits into a right-angled through hole near the lower end of the body.

The upper end of the shaft rod 20 extends beyond the rivet head 11 and extends over the article engaging head 1.
2 and is exposed in the upper space.When installing the stud on the entire waist, the exposed portion can be grasped and pulled upward.

In this embodiment, a large number of studs are manufactured by connecting the upper ends of each shaft rod in the horizontal direction, and one stud is inserted into the mounting hole one after another using a repeating gun developed by the present applicant (Japanese Patent Publication No. 55-20777). Since it is assumed that the intended stud will be installed, a shaft head 22 with a slightly complicated shape is attached to the upper end of the shaft rod due to the necessity for feeding and installation operations.
2 is removed together with the extending portion of the shaft rod 20 as described later after the stud is attached, or the article engaging head 12 is replaced with the riveting head 1.
1, the shaft head or the upper part of the shaft rod may be used as the object engaging head.

In this embodiment, a downward-facing annular pawl 23 is formed in multiple stages on the outer periphery of the intermediate portion of the shaft 20, and the hollow stud 10, which is injection molded using a double molding method and wraps around the shaft 20, has the above-mentioned annular shape. An upward inner circumferential claw portion 15 facing the claw portion 23 is formed.

As a desirable consideration, the outer diameter of the third Nissin claw 23' from the bottom of the multi-stage annular claw 23 of the shaft rod 20 is larger than that of the upper part, so that the corresponding inner circumferential claw part on the hollow stud side. 1
5 is also similar.

In any case, due to the presence of the claw portion 23 of the shaft rod 20, the portion of the chain body 14 where the corresponding claw portion 15 is located has a slightly thinner wall as shown in the figure. When the chain is buckled radially, the buckling itself becomes easy, and the pulling force of the shaft rod 20 is relatively light.

This is also an effect that has not been seen in the past. In addition, in the case of the present invention, the annular claw portion 23 of the shaft 20 has no claw portion above it, so that a downward annular shoulder is formed as shown in the figure. 24 has been completed.

As a result, an upwardly directed annular engagement step 16 is naturally formed on the inner periphery corresponding portion of the chain due to the double molding.

As will be described later, this configuration is a feature of one of the rivet parts of the present invention.

To attach this stud to the mounting body P as shown in FIG. 3, first insert the hollow stud chain body 14 into the hole of the body P, and then
Alternatively, the shaft rod 20 is pulled up while pressing the article engaging head 12 thereon against the surface of the mounting body P.

Since the chain body 14 is easily buckled due to the presence of the split groove 13, when the shaft rod 20 is pulled up, it immediately buckles radially, expands its outer circumferential dimension, spreads to the rear surface of the mounting hole, and causes the rivet head 1 to buckle.
In combination with 1, the mounting body is clamped.

This pulling up of the shaft rod 20 is carried out between the claw portion 23 and the inner peripheral claw portion 1 on the chain side.
5, the inner circumferential pawl acts as a non-return pawl to restrain the shaft 20 in that position when the pulling up of the shaft 20 is stopped.

In this embodiment, the inner peripheral pawl 15, especially near the rivet head 11, has a relatively small diameter, whereas the pawl 23' at the bottom of the shaft that has been pulled up has a larger diameter, so that it is firmly fitted. At the same time, since the plurality of claws 23' and the inner circumferential claws 15 are engaged simultaneously, the outer circumferential surface of the shaft rod and the inner circumferential surface of the chain body come into pressure contact over a wide range, and the presence of the above-mentioned rivet head also creates a watertight seal. This is an ideal configuration if you want to have sex.

In particular, as mentioned above, in this case, since the annular engagement step part 16 is formed on the periphery of the chain body, even if the shaft rod 20 is completely pulled up, at least the lowermost pawl 23 or in this case Since the chain 23' engages with this in a non-returning manner, even if the chain body tries to return to its original unbuckled state, it can be effectively stopped because the chain body is made of plastic and is elastic.

Conversely, since the force that causes the chain to return to its original state is the force that pulls down the shaft 20, this force becomes a force that presses the claws that are in contact with the locking step 16 more strongly, and on the contrary, it This increases the stopping power and the ability to secure it to the mounting hole.

In other words, according to this proposal, it not only opens the door to the use of elastic materials in this type of blind rivet, where elastic materials could not be used in the past, but it is also extremely rational that the elastic force can contribute to strengthening the fixing force. This can lead to negative consequences.

In the case shown in Figure 3, the upper part of the shaft portion 20 that protrudes unnecessarily after the stud is installed is cut off, but the remaining portion remains as the core rod of the hollow stud 10 and contributes to its rigidity when viewed as the original stud of the present invention. become.

In addition, in the state shown in Figure 3, if an umbrella-shaped or bowl-shaped suction cup-shaped rivet head is used as the rivet head as in this embodiment, the entire periphery of the rivet head is pressed against the mounting body P, making it tightly contact. This helps improve watertightness.

Further, since the mutually meshing pawl portion 23' and the inner circumferential pawl portion 15 engage at a position between the stud head 11 and the radially expanded chain body 14, as shown in FIG. The outer peripheral portion of the chain corresponding to the above position is expanded by the amount of expansion 23'.

Therefore, if the diameter of the hole in the attaching body P is made to match the outside diameter of the chain as much as possible, so that it can be inserted somehow, the chain and the hole edge will come into close contact with each other due to the mutual engagement of the claws, and the engagement of the claws will also be improved. It is stronger, and the holes in the mounting body and the hollow rivets, and the hollow rivets and the shaft rod, come into contact with each other reliably, which is also an advantage for those who want to achieve watertightness.

As described above, one embodiment has been explained, but in this invention, the stud can be attached by only one-sided operation of pulling up the shaft rod, and after installation, whether or not to cut off the excess shaft rod depends on the head The shape of the welding machine is a completely arbitrary design issue, but if the resistance welding machine is replaced with an inexpensive repeating gun, for example when used as a molding mounting stud for a car, difficult welding control techniques can be solved. There is no need to take precautions against corrosion or welded parts, and local painting for rust prevention can also be omitted.
There are some notable effects.

In addition, in cases where watertightness is particularly required, the presence of the rivet head, or by making the rivet head into a suction cup shape, makes it easy to ensure close contact between the mounting hole edge and the chain body. This can produce extremely satisfactory results, and attachment to a curved plate or the like can sometimes provide sufficient functionality.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the present invention, FIG. 2 is a side view similarly showing a hollow stud in cross section, and FIG. 3 is a cross sectional view of the state after installation. In the figure, 10 is a hollow stud, 11 is a stud head, 12 is an article engaging head, 14 is a chain body, and 20 is a shaft rod.

Claims (2)

[Scope of utility model registration request] (1) A hollow chain body that hangs down from the rivet head, and a chain that is housed within the chain body, the lower end of which is engaged with or fixed to the lower end of the chain body, while the upper end extends beyond the rivet head; The part housed in the body has a non-return claw, and a hollow shaft with a downward annular shoulder above the non-return claw is formed by double molding of plastic on the inner circumferential surface of the chain body above the waist. The annular shoulder forms an upward annular engagement step that engages with the non-return pawl, the rivet head has a suction cup shape, and an article engaging head is provided above the rivet head. A stud with a plastic rivet featuring. (2) The article securing head extends in the axial direction from the rivet head,
The plastic stud with rivets according to claim (1), characterized in that the stud terminates in a radially projecting flange portion.