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    • THE CRAFTSMANSHIP OF YKK 03

    Why zippers don’t come open on their own

    Come to think of it, on things like jeans, the zipper doesn’t come open on its own. Despite the fact that it moves smoothly when being zipped open and closed… That’s because zipper sliders have a locking function.

    The zipper stays closed thanks
    to the locking function

    The zipper won’t move when locked!

    Originally, zippers did not have a locking function. However, when wearing clothes, the slider could gradually slip down due to gravity as you move, causing the zipper to open unintentionally-which is inconvenient. To prevent this, zippers with a “locking function” were developed.

    The locking function mechanism

    A mechanism concealed within the slider is designed to activate the lock in tandem with the movement of the puller.

    If the lock pin catches, the zipper locks!

    An example is the case of sliders used on items such as jeans. When wearing jeans, if you keep the puller down, a part called the lock pin catches on the elements, preventing the zipper from opening or closing.

    When the pin is lifted, the lock releases!

    Raising the puller to a 90 degree angle lifts the pin, releasing the lock and allowing the zipper to open and close smoothly.

    Those tiny lock pins play a big role! Some sliders release the lock without needing to raise the puller to a 90 degree angle.

    Gently pulling the puller releases the lock

    With an automatic lock slider type, simply grasp the puller and give it a gentle pull to release the locking function.

    Easy opening and closing through
    the movement of a spring!

    For example with this type, The top surface (cover) of the slider has a spring-like mechanism; when the puller is held, the entire slider lifts up and the lock releases. The lock stays engaged unless the puller is held.

    It’s amazing that the locking function makes it possible for the zipper to only move when the user wants it to! In this way, zippers incorporate all sorts of ingenious features in places you might not notice at first glance.

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