PURPOSE: To make the middle and the outer legs of an E-shaped ferrite magnetic core equal in molding density, where the tip of the middle leg is smaller than its root in cross-sectional area.
CONSTITUTION: A stepped die 2 provided with three through-holes and steps is installed on a die plate 1, a middle leg lower punch 3 is fixed to a second punch holder 6 on a base plate 7, two outer-leg lower punches 4 and 5 are fixed to a first punch holder 8 held at the base plate 7 in a vertically movable manner penetrating through the second punch holder 6, the two outer-leg lower punches 4 and 5 and the middle leg lower punch 3 are so composed as to be separately set in a vertical position, and the middle and the outer leg are separately controlled in fill by different mechanisms to be equal in molding density.
ABE NAOYA
HIRAO SATOSHI
ANDO HIROSHI
| JPS4939874A | 1974-04-13 |