1. Field of the Invention
The present invention generally relates to a manufacturing method of zipper; and, more particularly, it relates to a manufacturing method of waterproof coil zipper able to avoid permeation in a fastened state.
2. Description of the Related Art
Zippers are daily used tools for modern lives. Many products such as clothes, bags, shoes are able to be opened or closed fast by using zippers, which surely improve the convenience of our lives. However, in order to broaden the use of zippers, a requirement in “waterproof zipper” able to be watertight when in a fastened state is gradually raised since the above said products are sometimes used outside in a rainy or windy environment. Thus, inventions of nylon waterproof zipper are gradually proposed.
The above zippers may be plastic zippers, metal zippers, coil zippers, etc. The coil zippers can be categorized as nylon zippers or polyester zippers according to different material used.
Early nylon waterproof zippers provide the waterproof function through applying a water repellent coating to the tapes of a nylon zipper. Unfortunately, this kind of conventional nylon waterproof zippers cannot provide a wholly watertight performance when fastened since water may permeate through a fastened zipper via the gap between its engaged teeth. Besides, the water repellent coating may flake off the tapes after a period of time. The above reasons both worsen permeation of the nylon waterproof zippers.
Accordingly, an improvement of nylon waterproof zippers is proposed, which is shown in
However, since the elastomer body 93 and waterproof film 94 are formed by two separate steps, the above manufacturing method is not efficient enough. Moreover, the waterproof film 94 can flake off the elastomer body 93 because there is a combining junction between the elastomer body 93 and waterproof film 94 since they are not integrally formed, and thus the watertight performance of the nylon waterproof zipper 9 may reduce as time goes by.
As a result, it is necessary to improve the conventional nylon waterproof zipper.
It is therefore the objective of this invention to provide a manufacturing method of waterproof coil zipper forming an anti-permeating body and a waterproof layer simultaneously, so as to simplify the manufacturing steps and to increase manufacturing efficiency.
Another objective of this invention is to provide a manufacturing method of waterproof coil zipper that integrally forms the anti-permeating body and waterproof layer, so as to ensure a combination of these two members and to prolong lifetime of the produced waterproof coil zipper.
One embodiment of the invention comprises: preparing a coil zipper including two tapes and two teeth sets, wherein the two tapes are spaced from each other to define an interspace therebetween, wherein each of the tapes has a first surface and a second surface opposite to the first surface, the second surface of each of the tapes connects with a respective one of the two teeth sets, and the two teeth sets engage with each other; extruding a melted polymer material to fill a gap between the two teeth sets and the interspace between the two tapes, and to cover the first surfaces of the two tapes; cooling the polymer material to integrally form an anti-permeating body and a first waterproof layer, wherein the anti-permeating body is filled in the gap between the two engaged teeth sets, and the first waterproof layer covers the first surfaces of the two tapes; and cutting the anti-permeating body by a cutting tool.
In a preferred form shown, cutting the anti-permeating body further comprises cutting the anti-permeating body along a longitudinal center plane of a combination of the engaged teeth sets.
In a preferred form shown, the manufacturing method further comprises applying an adhesive to the first surfaces of the two tapes before extruding the melted polymer material.
In a preferred form shown, extruding the melted polymer material further comprises covering the second surfaces of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a second waterproof layer on the second surface.
In a preferred form shown, the manufacturing method further comprises applying an adhesive to the second surfaces of the two tapes before extruding the melted polymer material.
In the preferred form shown, preparing the coil zipper further comprises spacing two opposite third surfaces of the tapes by a predetermined distance, with each of the third surfaces linking the first and second surfaces of a respective one of the two tapes.
In the preferred form shown, each of the two tapes further comprises a fourth surface opposite to the third surface thereof. Based on this, extruding the melted polymer material further comprises covering the fourth surface of one of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a third waterproof layer on the fourth surface of the one of the two tapes.
In the preferred form shown, the manufacturing method further comprises applying an adhesive to the fourth surface of the one of the two tapes before extruding the melted polymer material.
In the preferred form shown, each of the two tapes further comprises a fourth surface opposite to the third surface thereof. Based on this, extruding the melted polymer material further comprises covering the fourth surfaces of both of the two tapes by the melted polymer material, and cooling the polymer material further comprises forming a third waterproof layer on each of the fourth surfaces.
In the preferred form shown, the manufacturing method further comprises applying an adhesive to the fourth surfaces of both of the two tapes before extruding the melted polymer material.
The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
In the various figures of the drawings, the same numerals designate the same or similar parts. Furthermore, when the term “first,” “second,” “third” and similar terms are used hereinafter, it should be understood that these terms refer only to the structure shown in the drawings as it would appear to a person viewing the drawings, and are utilized only to facilitate describing the invention.
Referring to
Referring to
The second step is extruding a melted polymer material to fill a gap between the two engaged teeth sets 2 and the interspace between the two tapes 1, and also to cover the first surfaces 1a of the two tapes 1. In this embodiment, the melted polymer material is applied to a side of the coil zipper, which has the first surfaces 1a, for the polymer material to permeate into the said gap and to cover the first surfaces 1a. Preferably, the polymer material is Thermoplastic polyurethanes (TPU) or the likes of TPU, which can attach to cloth or leather with a high stickiness. Continuously, with cooling of the polymer material, the polymer material forms two parts: an anti-permeating body 3 and a first waterproof layer 4, which are integrally formed and connected, with said anti-permeating body 3 filled in the gap between the two engaged teeth sets 2, and with said first waterproof layer 4 covering the first surfaces 1a of the two tapes 1.
Finally, cutting the anti-permeating body 3 along a longitudinal center plane of the combination of the engaged teeth sets 2 by a cutting tool “K,” which approaches the anti-permeating body 3 from a side of the coil zipper where the first surfaces 1a locates, is performed. As a result, the two teeth sets 2 are able to be unfastened again but the coil zipper is watertight now when said teeth sets 2 engage, and, namely, a waterproof coil zipper is provided.
Specifically, when the manufactured waterproof coil zipper is in a fastened state in which said teeth sets 2 are engaged with each other, not only the first waterproof layer 4 is able to prevent the tapes 1 from the wet, but also the anti-permeating body 3 can avoid any liquid passing through said waterproof coil zipper via the gap between the two teeth sets 2. Besides, the combination between the anti-permeating body 3 and first waterproof layer 4 is surely improved since they are formed integrally. Therefore, a wholly watertight performance can be provided for a long time period. Furthermore, instead of connecting a waterproof zipper with cloth or leather by sewing that results in pinholes significantly lowering watertight performance, the polymer material forming the first waterproof layer 4 can be used to seamlessly connect the manufactured waterproof coil zipper with cloth or leather in a hot-melt-adhesion manner, so as to achieve an improved watertight performance.
Referring to
Referring to
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In sum, with the above illustrated embodiments of the manufacturing method of waterproof coil zipper, the anti-permeating body 3 and the first waterproof layer 4 can be formed simultaneously in the same step, and thus the manufacturing steps for the waterproof coil zipper are simplified to shorten the manufacturing cycle time, lower the manufacturing cost, increase the manufacturing efficiency, and prolong the lifetime of products.
Although the invention has been described in detail with reference to its presently preferable embodiments, it will be understood by one of ordinary skill in the art that various modifications can be made without departing from the spirit and the scope of the invention, as set forth in the appended claims.
Number | Date | Country | Kind |
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101142669 | Nov 2012 | TW | national |