METHOD FOR MANUFACTURING GLOW PLUG FOR DIESEL ENGINES BY PRESSING WORK TO FORM EXTERNAL SHAPE AND HOLE INTO WHICH HOT WIRE COIL IS INSTALLED AND PERFORMING ALL PROCESSES CONTINUOUSLY AND SIMULTANEOUSLY

摘要

PURPOSE: To provide a method capable of continuously mass-producing glow plug for diesel engines while minimizing unnecessary loss of work. CONSTITUTION: A manufacturing method of glow plug for diesel engines comprises a cutting process of cutting a work(M) supplied to a cutting dies(2) to a certain length by a cutting knife(6); a hardening process of flatly hardening both fracture surfaces of the cut work while making a central seat surface for hole formation on an upper portion and a lower portion of the work by inserting the cut work into a first dies(10a) and pressing the cut work by a punch part(10b); a hole formation process of forming holes to a certain depth on the upper surface and the lower surface of the work by inserting the work into a second dies(20a) and pressing the work by a punch part(20b); a perforation process of forming a through hole by inserting the work into a third dies and pressing the work by a punch part, thereby removing the work between the upper hole and the lower hole formed in the hole formation process; an extrusion process of inserting the work into a fourth dies and pressing the work by a punch part, thereby forming in multistage an external shape of the work formed in the above processes; and a head part forming process of forming a head part on the upper outer surface of the work by inserting the work into a fifth dies and pressing the work by a punch part.