| 摘要 |
Pressurized viscous fluid(62), pumped by annular pistons (11), flows in contact with one surface of a blank(73) inwardly from the periphery thereof, thereby to force the opposite surface of the blank against a low friction surface, thereby to pressurize the blank and exert viscous drag force on the surface of the blank to extrude the peripheral portion of the blank inwardly, in cooperation with a ram(28) perpendicularly engaging the central portion of the blank, to deep draw the blank through a die opening(53). The viscous fluid can be applied to inwardly extrude the blank uniformly or non-uniformly.
|
