Safety pin

The safety pin is a variation of the regular pin which includes a simple spring break mechanism and a clasp. The clasp serves two purposes: to form a closed loop thereby properly fastening the pin to whatever it is applied to, and to cover the end of the pin to protect the user from the sharp point.

Safety pins are commonly used to fasten pieces of fabric or clothing together. Safety pins, or more usually a special version with an extra safe cover, called a nappy pin, are widely used to fasten cloth diapers (nappies), as the safety clasp, while remaining ingestion hazard, prevents the baby from being jabbed. Similarly, they can be used to patch torn or damaged clothing. Safety pins can also be used as an accessory in jewelry, like earrings, chains, and wristbands. Sometimes they are used to attach an embroidered patch. Size 3 is often used in quilting and may be labelled for purchase as a "quilting pin". Size 4 and larger may be called "blanket pins" and deemed acceptable as kilt pins for informal dress, depending upon design and appearance.

The fibula, a form of brooch, was invented by the Myceaneans on the Greek Peloponnesus between the 14th and 13th Century BC, and is considered an early precursor to a safety pin since they were used in a similar manner. However, it had a major flaw. It had no clasp or spring at the end to help put it in place. Over the centuries, the fibula became forgotten.

American mechanic Walter Hunt is regarded as the inventor of the safety pin that bears resemblance to those used today. The safety pin included a clasp that covered the point and kept it from opening, and a circular twist at the bend to act as a spring and hold it in place. Charles Rowley (Birmingham, England) independently patented a similar safety pin in October 1849, although the company no longer makes these.

Hunt made the invention in order to pay off a $15 debt to a friend. He used a piece of brass wire that was about 8 inches long and made a coil in the center of the wire so it would open up when released. The clasp at one end was devised in order to shield the sharp edge from the user.

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Wikipedia