Before fully getting to know the meaning of the term rack, it is essential to discover its etymological origin. In this case, we can state that it derives from the French, specifically from the word “crémailleré” that emanates from the Latin “cramaculus” and this, in turn, from the Greek “kremaster”, which meant “hanging”.

The term is used to refer to closing used in clothing, bags and other products.

ZipperThe zipper consists of two strips that, on their edges, present teeth that lock (to close) and unlock (to open) each other. To operate the mechanism, the person you must move a cursor or handle up or down or to one side or the other.

Also called zipper Or simply closing, the zipper allows join or separate two pieces or two parts of the same piece. The jackets (jackets), the pants, wallets, suitcases (suitcases) and bags are some of the items that usually have zippers.

Thus, we can state that every zipper consists of a belt or textile band, teeth, an upper stop, the chain, the puller, the separator tube, the reinforcement, the separator box, the lower stop, the lower part and the cursor or cart.

Within the field of fashion, it is important to know that there are different types of zippers, among which the following stand out:
-Metallic zipper. This has an attractive finish, is made of brass material and is used a lot because it stands out for its resistance. In the same way, we cannot overlook either that it can be presented in a wide variety of colors.
-Multi-purpose, which has the particularity of being made of polyester and is identified because the teeth are in the shape of a spiral. It has different uses and can be found for sale with dimensions ranging from 10 centimeters to the meter.
-Injected zippers are those that are usually thick and also offer great resistance. Of course, their teeth are plastic. They can be found mainly in sportswear as well as in what are backpacks and bags and even in footwear such as ankle boots.

In the field of mechanics, a zipper is a bar that presents teeth on one edge, making it possible to engage with a pinion to convert a rectilinear motion to a circular motion and vice versa. In this type of mechanism, the pinion meshes with the rack in such a way that, when the pinion rotates, the rack moves linearly.

The address of the automobiles, for example, it has a zipper. The steering wheel is linked to a steering column, in turn associated with a rack and pinion, which allow moving an articulated bar that is linked to the wheel support.

In a rack railway, the train advances from its coupling with the via through a third rail which is precisely a zipper. The pinion mounted on the locomotive transmits the force to this rail.

These railways are usually found in mountain areas since the rack facilitates the ascent of the slopes. The system in the roller coasters.