MULTIPLE SHIELD DRILLING MACHINE

摘要

PURPOSE:To prevent the generation of strains at a tail part of a lead frame produced by earth load. CONSTITUTION:A shield frame 3 is divided into sided shield frames 3a and a central shield frame 3b. The divided portions are doubled and enabled to slide in such a manner that the central shield frame 3 may be positioned in the inner side, thereby forming a doubled portion 3c. A load transmission member is installed to the inner surface of the tail part of the central shield frame 3b which is positioned at an upper part doubled part 3c.