Structure and Mechanism Introduction

I. Introduction to the Locking Mechanism During Transportation

1. Design of the Seal GasketFood-grade silicone is preferred. The cross-sectional shape adopts a “convex” profile (see diagram below). When the lid is closed, the gasket is compressed and deformed by the groove in the main body of the lunch box, forming multiple sealing lines to enhance airtightness.
2. “Micro-Interference” Design of the HingeThe hinge shaft and bushing adopt an interference fit of 0.05~0.1mm. When the lid is closed, the inherent assembly tightness of the hinge drives the lid to fit closely with the main body, providing initial compression force for the gasket.
3. In terms of the design for airtightness, we did have some oversights. In addition to the micro-interference fit hinge and the convex seal gasket, the lid should also be equipped with flip-up/press-down clips (designed on the edge of the lunch box lid, on the side opposite the hinge). These clips would apply mechanical force to tightly press the lid onto the main body of the lunch box, further enhancing airtightness and ensuring no leakage during transportation. This particular aspect has not yet been reflected in our design.

II. Method to Prevent the Opened Lid from Falling During Use

Hinge with Built-in Limit Stops
Convex “limit stops” are designed on both sides of the hinge shaft connecting the lid and the lunch box body. When the lid is opened to 90°, the contact surfaces of the limit stops and the hinge base abut against each other, forming a physical barrier to prevent further rotation of the lid. Meanwhile, the lid remains stable by utilizing the hinge’s own assembly tightness. (Sorry, no suitable detailed picture of the limit stop is available; you may search for it yourself.)

III. Introduction to the Canopy Mechanism

Its folding structure consists of a linkage fold between metal supports and a fabric enclosure. The metal supports employ foldable hinge designs, enabling the supports to collapse through the rotation of these hinges. The fabric enclosure is connected to the metal supports via fasteners and can be retracted accordingly during the folding process, resulting in a compact folded form overall. (The fabric is waterproof and lightproof.)