Container mold. An Italian company has patented a space-saving mold and method for making collapsible foam containers.
The patent, awarded to Bazzica Engineering Srl of Trevi, Italy, describes a mold that forms the containers from foamed PE, PP, PS or copolymers. Such containers have a bottom with four walls hinged to it, which allows them to be folded flat to save space for transportation or storage. However, these containers are typically molded in the form of a blank — a flat sheet that has thinner areas connecting the lateral walls to the bottom wall.
The major drawback of the traditional manufacturing method is that the blank requires a large and bulky mold that is difficult to handle.
Bazzica’s invention overcomes this difficulty by molding the container in its upright configuration.
“As a result, compared with conventional molds configured to mold open containers (i.e., in the form of blanks), Mold 1 is relatively compact, so each machine can be fitted with a greater number or quantity of molds to increase output of the machine,” the patent states.
Furthermore, “by forming hinges and recent joints with the container in the erect configuration, the areas connecting the moving parts of the container are shaped more accurately, increasing the rigidity and stability of the container, making it able to withstand repeated assembly and disassembly.”
The patent describes a mold with two halves that close to form a mold cavity. The mold has a forming device for the hinges that includes parting and compression members, located opposite each other. Each member has a resting position outside of the mold cavity and a working position within the cavity.
The compression member compresses plastic material toward the parting member and cooperates with it to form a higher-density portion of the container, defining the hinge. Additionally, the compression member includes a pad that engages a channel in the mold.
The mold includes a hydraulic actuator for each parting member and compression member.
Patent 10,717,215; issued July 21
Patents and patent applications can be viewed at www.uspto.gov
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