| 摘要 |
PURPOSE:To produce a bushing plate having a uniform wall thickness without cracking nor breaking, by forming many circular protrusions on the whole plate by pressing with the top and bottom forces. CONSTITUTION:A top force 12 having many circular tapered chip holes 11 perforated on the undersurface and recessed forces 13 opposite to the chip holes 11 of the top force 12 are provided on the top surface. A bushing plate 1' is inserted between the top force 12 and the bottom force 15 obtained by positioning steel balls 14 on the recessed forces 13 to lower the top force 12 and press the material 1'. Thus, the material 1' is inserted into the chip holes 11 by the steel balls 14 using the plastic deformation and form circular protrusions 16, which are then punched and reamed from the rear thereof by the circular protrusions 16. Thus, tapered nozzle holes 17 are concentrically perforated to form nozzles 18 and afford the aimed bushing plate 19. |
