| 摘要 |
PROBLEM TO BE SOLVED: To provide a press forming method for dielectric blocks which prevents the block from cracking around the step portion by improving the accuracy of contact position between upper and lower core bars. SOLUTION: Keeping the upper core bars 72a, 72b in contact with the lower core bars 71a, 71b respectively, all the upper core bars 72a, 72b and the lower core bars 71a, 71b are slid down toward the lower punch 61 side and the contact position F between the upper core bars 72a, 72b and the lower core bars 71a, 71k is shifted to the designated position in the cavity 51, while dielectric powder 4 in the cavity 51 is not pressured. Then keeping the upper core bars 72a, 72b in contact with the lower core bars 71a, 71b respectively, the dielectric powder 4 in the cavity 51 is compressed by the upper punch 62 and the lower punch 61 to form the dielectric block. |
