On the basis of the "center of gravity" theory, Archimedes also discovered the principle of leverage, that is, "when two things are equilibrium, their distance from the fulcrum is inversely proportional to their weight." That is, "when two things are balanced, their distance from the fulcrum is inversely proportional to their weight." "According to the style of the hinge development stage, it is divided into: one-stage force hinge, two-stage force hinge, hydraulic buffer hinge, touch self-opening hinge, etc.; Two-stage force hinges, short arm hinges, 26-cup miniature hinges, marble hinges, aluminum frame door hinges, special angle hinges, glass hinges, rebound hinges, American hinges, damping hinges, thick door hinges, etc.

Changing the direction of a force means that one side can apply force downwards, and the other side can generate an upward force. No need to make holes is what we call bridge hinges. The bridge hinge looks like a bridge, so it is commonly known as a bridge hinge. It features no need to drill holes in the door panels and is not limited by specifications. Specifications are: small, medium, large. Holes need to be made, that is, spring hinges that are now commonly used on cabinet doors. Its features: the door panel must be punched, the style of the door is limited by the hinge, the door will not be blown open by the wind after it is closed, and there is no need to install various bumper spiders.