Spring balancer, also known as tension balancer, is an auxiliary tool matched with operating tools. No matter on the assembly line or various forms of workpieces, it can be used where manual tools and lifting equipment are used. It is also known as "elastic Crane" because the spring balancer can be used with guide rail to move left and right, which is similar to the shape of a small crane, so it is called "elastic Crane". Its working principle is also particularly simple. The balancer mainly relies on the energy of the internal scroll spring to adjust the elastic potential energy and gravity to achieve a certain balance, so that the tools suspended on the wire rope hook of the balancer are in a "suspended" state. This is the working principle of the spring balancer.