Patent ID: 7987578
Filing Date: 2011-08-02
Classification: B29C,B65D,Y10T

Abstract:
1. In a method of molding and assembling a container having a lid connected thereto by the steps of injecting a molten plastic liquid into a mold to form a container body having an open top and to form at least one lid situated adjacent one edge of the open top, the one edge of the container body being formed with hinge parts along a length thereof and the lid being formed with hinge parts along an edge thereof, opening the mold by separating a mold cavity portion of the mold from a mold core portion of the mold so that the container body and the lid are supported by the mold core portion, moving a first part of the mold core portion so that the connecting parts on the lid are aligned with the connecting parts on the one edge of the container body and pushing the lid away from the first part of the mold core portion towards the container body on a second part of the mold core portion until the connecting parts on the lid are engaged with the connecting parts on the one edge of the container body to connect the lid to the container body, the improvement which comprises: in the step of injecting a molten plastic liquid into a mold, constructing the mold so that the hinge parts formed along the one edge of the container body are formed as pin segments along a hinge line and the hinge parts formed along the edge of the lid are formed as generally U-shaped knuckles along a hinge line, with each knuckle having opposed side walls which form a slot having an opening at one end and a bearing portion at an opposite end and which opens upwardly with respect to a top surface of the lid and wherein the opposed side walls of the slots of a least certain of said knuckles have ribs protruding inwardly from the side walls between said opening and said bearing portion to retain corresponding pin segments of the container body in said bearing portions of said slots when the lid is connected to the container body, and constructing the mold so that an end knuckle is formed at each end of said hinge line on the lid, each said end knuckle having an opening on an inside end thereof facing a mid portion of the lid, and a corresponding cantilever in extending outwardly at each end of said hinge line on the container body is formed whereby said openings in said end knuckles capture said corresponding respective cantilever pins when the lid is connected to the container body; and in the step of pushing the lid away from the first core portion, the lid is pushed towards the container body until the slots in the knuckles on the lid are engaged with the pin segments on the one edge of the container body and the openings in the end knuckles capture the cantilever pins to rotatably connect the lid to the container body whereby when the lid is rotated to a closed position, the slots face upwardly with respect to the top surface of the lid and the pin segments engage the bottoms of the slots to prevent the lid from being pulled off the container.