(1) Spring wire diameter d: the diameter of the copper wire used to make the spring wire;
(2) Spring coil diameter D: the outer diameter of the spring wire coil;
(3) Spring wire inner coil diameter D1: the inner diameter of the spring wire coil;
(4) Spring wire spiral length L: the static length of the spring wire when not subjected to external force;
(5) Spring wire working length L0: the dynamic length of the spring wire when subjected to external force;
(6) Spring wire unfolded length A: the total length of the straight line required to wind the spring wire;
(7) Spring wire tail length: the tails at both ends are represented by L1 and L2 respectively;
(8) Spiral direction: There are left and right spirals, right spiral is commonly used, and right spiral is generally used if not specified in the drawing.
