Coupling is a device that connects two shafts or shafts and rotating parts, and rotates together without disengaging during the process of transmitting motion and torque. It does not change the direction of rotation and the magnitude of torque during the transmission process. This is a variety of The common function of the coupling, the elastic coupling also has different degrees of shock absorption and buffering function, and the coupling also has an overload protection function.The rigid coupling acts as a connection and can only transmit motion and torque, without other functions.Examples: flange couplings, sleeve couplings, clamp couplings, parallel shaft couplings, etc.Flexible couplings without elastic elements can not only transmit motion and torque, but also have different degrees of axial, radial and angular compensation.Examples: gear couplings, universal couplings, chain couplings, slider couplings.The flexible coupling of the metal elastic element transmits movement and torque, has different degrees of shock absorption, cushioning effect and compensation amount, and improves the working performance of the transmission system.Examples: diaphragm coupling, serpentine spring coupling.The non-metal elastic element flexible coupling transmits movement and torque, has different degrees of shock absorption, cushioning effect and compensation, and improves the working performance of the transmission system. , For example: elastic pin coupling, plum blossom coupling, star coupling, elastic sleeve pin coupling, tire coupling, etc.The coupling transmits motion and torque, overload protection, and the flexible coupling also has different degrees of compensation performance.Examples: steel ball type, steel sand type, friction type, hydraulic type, pin type and other couplings.