摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a main mold for glow plug and a method for manufacturing a glow plug with high strength that is hardly deformed by excessive fastening even when its diameter is reduced and/or length is increased. <P>SOLUTION: Disclosed is a method for manufacturing a main fitting 3 or 6 for glow plug that includes: a top end 11 including a heater; a threaded section 12 formed continuously to one end of the top end 11; and an axial hole 14. This method for manufacturing the main fitting 3 or 6 for glow plug includes a forging process of performing multistage cold forging on bars with different diameters having a thick portion and a thin portion to form at least the top end 11 with the thick portion. A method for manufacturing glow plugs 1A and 1B includes a process of fixing the heater to the top end 11 of the main fitting 3 or 6 for the manufactured glow plug. <P>COPYRIGHT: (C)2012,JPO&INPIT |