SCISSORS

۶۲ طرفدار

۱۲۵ انتشار • فعال از ۲۰۱۶

Scissors or shears are hand-operated cutting tools that consist of a pair of pivoting blades whose sharpened edges slide firmly against and past each other when the handles (shank) on the opposite side of the pivot are squeezed shut. This causes the target material in between the blades to be divided by the combined effort of both cutting and shearing. Scissors are usually used for cutting thin materials such as paper, cardboard, metal foil, cloth, rope and wire, although a large variety of scissors/shears exist for specialized purposes, and their design details often dictate which is best for the intended job. While all scissors largely follow the same working principle, heavy-duty scissors intended for cutting tough materials tend to be called shears instead of scissors (e.g. pruning shears and grass shears), and some larger, two-handed implements are called trimmers instead (e.g. hedge trimmer). Choosing the optimal type of scissors/shears is crucial, as otherwise it can cause unwanted damage to the target material and/or the instrument itself. For example, hair-cutting shears and kitchen shears are functionally equivalent scissors, but hair-cutting shears have specific blade angles ideal for cutting heaped bundles of hair, and using the incorrect type of scissors will result in increased damage or split ends, or both, by breaking the hair; kitchen shears, also known as kitchen scissors, are intended for cutting and trimming tough food materials such as meat, tendon and bones. Surgical scissors, used to divide tissues and trim/reshape implants during surgical operations, have even a greater variety to deal with different anatomical and procedural circumstances. Most scissors have a ringed handle to allow readily opening for repeated cutting, and some even have spring between the shanks to assist opening (especially for shears with straight handle).