Its impossible without mold structure and wide-mouthed container body having an undercut

摘要

PROBLEM TO BE SOLVED: To provide a wide-mouthed container body, which has two undercuts, which are formed on a male screw on the outer peripheral surface of a mouth-to-neck part and on the inner peripheral surface of a shoulder, respectively, and the undercuts are extracted forcibly from a die one after another, and which has a trunk whose outer diameter is made identical with that of a cap, and also to provide a forced extraction die structure for the container body.;SOLUTION: A male die is used to regulate the bending elastic modulus of the material of the wide-mouthed container body 100, the height H of the thread of the male screw 111, the angle F of the flank of the thread, the flat width W of the front end face of the thread, a radius R₁ at an angled part of the front end face, a radius R₂ at the root of the thread, the wall thickness T of the mouth-to-neck part 110, a radius R₃ at the point where the inner peripheral surface upper end of the shoulder 120 connects to the inner peripheral surface lower end of the mouth-to-neck part 110, a radius R₄ at the point where the inner peripheral surface lower end of the shoulder 120 connects to the inner peripheral surface upper end of the trunk 130, and the width D of the undercut on the inner peripheral surface of the shoulder 120. The die has a forced extraction mechanism consisting of a die block for forming the top face and interior of the mouth-to-neck part 110, a die block for forming the exterior of the mouth-to-neck part 110, and a die block, which has a built-in center ejector pin at the center of the die block and forms the interior of the trunk 130. The die is used to forcibly extract the undercuts of the container body one after another.;COPYRIGHT: (C)2005,JPO&NCIPI