MadSci Network: Engineering |
The curls in a telephone cord are an anti-tangle mechanism. The longer a cord is, the more likely it is to get tied up in knots. This is very much like human hair (longer hair gets into more tangles). The curls in a telephone cord are a clever way to keep the cord short until you need it longer. As you move the headset away from the base, the cord stretches with you. A two foot curled cord can stretch to six feet as needed, and conveniently shrink back to two feet when you are done. The curls are made in a very similar approach the curls in human hair. The phone cord is wrapped around a heated rod. The heat softens the plastic insulation and molds it into a spiral, so when it cools the spiral is the natural shape.
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