Conical spring

A conical spring formed of a wire of a steel material, said wire having a cross-section and being coiled in one direction into a series of rings from a first level of a first base of said wire to form a first conical body having a first predetermined vertex angle and terminating at a second level from which said wire is coiled in a second direction reverse to said one direction into a another series of rings to form a second conical body terminating at a vertex having a third level, said second conical body having a second predetermined vertex angle;

• wherein said wire is coiled in reverse from said second direction to said third level of said second conical body into a third series of rings to form a third conical body.