| 摘要 |
PURPOSE: A method for manufacturing a trust lamp is provided to simply manufacture, to be economical due to a low scrap, to obtain durability of the trust lamp, and to reduce damage. CONSTITUTION: A method for manufacturing a trust lamp comprises: a step of forming a lower groove on the lower surface of a round rod by pressurizing an upper punch; a step of forming a step by classifying the round rod into a head unit of an upper part and a body of a lower part; a step of forming the head unit with large diameter and the body with small diameter, forming a plurality of punching grooves on the upper surface, and trimming lower edge of the head unit and lower edge of the body; a step of forming a hole inside the head unit and the body by a piercing process the body of the round rod, forming an upper step on the body of the round rod, and forming an upper part of the upper step with large diameter and a lower part of the upper step with small diameter; a step of forming a lower step on a lower part of the upper step and forming the diameter smaller in the order of the upper body, an intermediate body, the lower body; and a step of forming a plurality of ball bearing coupling grooves in a radial shape on the upper surface of the round rod and forming a plurality of protrusions by protruding outer circumference of the head unit in a radius direction corresponding to the ball bearing coupling groove. |
