DESIGN REVIEW #1
- Sandra Li
- Sep 30, 2019
- 2 min read
This week, the team focused on developing one final yoyo design. We met and strategized on the best way to design, machine, and assemble our chosen concept: the spinner yoyo.
To begin, the team chose to pursue the spin the bottle design (one of Max's ideas from the previous post). We ended up forgoing the bottle design in hopes of reaching more audiences and expanding the possibilities of our toy. As a team, we also decided to avoid electronics and focus on a purely mechanical system due to the fact that working with electronics is a nightmare, incorporating electronic systems limits our design capabilities, and no one on the team has sufficient experience with integrated electronic systems.
Therefore, we compiled a rough sketch of the yoyo consisting of three main injection molded parts, two thermoformed parts, and a bearing. The exploded view of the yoyo is shown below:
Here's a still shot of our exploded view:
Injection molded: Top and Bottom housing, spinner arrow, spinner arrow, color wheel cover
Thermoformed: clear window sheet, color wheel
Other parts: bearing, screws
Focusing on the main components, here are CAD snapshots of our initial yoyo design.
Top and Bottom Housing
The housing will be snap-fit together in a design similar to those we saw from previously made yoyos. A relatively simple design, the injection molded top and the bottom casing will sandwich a thermoformed sheet of clear plastic that acts as a window or a barrier so the inside components remain intact.
Snap fit interference is 0.01" for a diameter of 2.5"
Right now, we have to do some research on previous yoyos so we can have a better idea of how thick of walls need to be.
Partial Assembly
The video below shows a partial assembly of the main housing. You can see our snap fit mechanism below:
For more clarity on our snap-fit, we included cross-sections of our yoyo.
Internal Components
The inside of our yoyo consists of a thermoformed color wheel, a injection molded spinner arrow, a bearing, and an injection molded color wheel cover. Assembly in the internal components can be easily seen in the cross-section image above.
The thermoformed color wheel is going to look something like this (minus the arrow). The colors are still up for debate but we're aiming for a sleek, polished, classy color scheme.
A video of the full rendered yoyo can be found below:
Mold of Our Most Complicated Part
A preliminary mold of our most complicated part can be found below (bottom housing). Injection holes and mounting holes to be added in the near future. This mold includes a shrinkage factor of 5%.
With this initial design in mind, here are some of the questions that we need to ask ourselves?
- Will there be any manufacturing problems with the initial CAD models we have?
- Will our arrow be able to spin correctly?
- What do the instructors and our peers think of our design in terms of feasibility and coolness? What advice or suggestions do they have for us?
Comments