| 摘要 |
PURPOSE: To make drawing of sheet material possible with low blank holding force by providing a triangular drawing bead on blank holding face. CONSTITUTION: A sheet material is sandwiched by a die 1 and blank holder 3 and drawing is executed by a punch 4. A triangular bead 8 is provided to the blank holding face 1a of die 1. An angleαof the triangular bead is a practical range of 20-45 deg.. Since a low height triangular bead 8 generates high steady load, drawing of a work is made possible by low blank holding force. That is, the resistance force to drawing generated in deforming of a work 5 can be utilized. Further, the load adjustment at drawing is made easy and the product quality is stabilized as well. In addition, the loads to dies 1, 5 are reduced and die wear is reduced as well.
|
