Soy sauce cap redesign - Design for Manufacture, 2021
The Prompt:
Design and prototype a functional soy sauce cap. It must provide three different flow options, seal against the glass bottle, and be removable without being disassembled.
The traditional Kikkoman soy sauce cap has two openings, putting a finger over one spout allows the user to control the rate of flow of soy sauce. After some brainstorming on ways to make this feature work with three spouts, a moving core piece appeared to be the most compact option.
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The core piece has a notched bottom, the notches allow soy sauce to flow through to the 3 channels, but form a seal when pressed against the rubber o-ring.
Upper
1. Polypropylene pellets are
heated and injected through
gate.
2. Mold is cooled.
3. Mold opens.
4. Pins eject from top cavity.
5. Sprue is removed by hand.
Core
1. Polypropylene pellets are
heated and injected through
gate.
2. Mold is cooled.
3. Mold opens.
4. Pins eject mold from top
cavity.
5. Sprue is removed by hand.
Lower
1. Polypropylene pellets are
heated and injected through
gate.
2. Mold is cooled with water.
3. Mold opens.
4. Threading mold is removed
by counter-clockwise rotation.
5. Pins eject mold from bottom
cavity.
6. Sprue is removed by hand.
Polypropylene was chosen as the material for the cap. It offers several benefits:
-Resistant to acids. Soy sauce has a pH value of 4.8
-Food Grade
-Resistant to fracturing when flexed
-Temperature resistant up to 210° fahrenheit (dishwasher safe)
Function:
All three spouts of the cap are accessible at all times. Divots on the top signify the size of each spout. When pressed down, the bottom side of the core forms a seal against the o-ring. Therefore, the core acts as a button which can be pressed to regulate flow.
