As early as 2,200 years ago, our ancestors had taken the lead in inventing and using hinges. The door hinges were not "imported goods" but belonged to an "invention patent" of the Qin people. The hinge is a piece of furniture copper, commonly known as a hinge. It is a piece of metal that connects the two parts of the furniture and makes it possible to move. It consists of a pair of metal or non-metal blades connected by a pin, often two-fold. It is a device that connects, and rotates, a door, a cover, or other parts that require a swing switch. In home life, hinges can be generally divided into: ordinary hinges, pipe hinges, door hinges and other hinges.