Resonator Cone Fixture
The Challenge: Replace an existing fixture with a new fixture that would allow proper torqueing of assembly.
About:
As seen in pictures below, the old fixture was designed to restrict the head of the torque wrench while the assembly itself was turned to tighten. This defeated the purpose of using a torque wrench, as the handle would not click. The assembler therefore had no idea if it was torqued to spec. For a critical part in the beam line of an ion implanter, it was essential to bring this process back under intended control.
My Role:
Prototyping, CAD, Testing
Process:
Like any fixture, the key question was how to hold the workpiece. I deliberated between using mechanical stops or clamps, but choose mechanical stops so that the assembler wouldn’t have to spend time screwing a clamp or aligning the piece. I wanted to create a fixture cheaply and quickly by printing it on our FDM printer.
After testing a few prototype prints, it was clear that even a high-density print wouldn’t hold up to the torqueing force. I was able to argue that upgrading to metal fixture would not only fix the issue, but let the fixture last for years. Then had it made by sending drawings with required geometric dimensioning and tolerancing to be made in our machine shop.
Old Fixture
Prototype Design with Inserts for Clamps
Final Design
Result:
The result was a durable fixture that allowed the assembly to be torqued properly in seconds. As a bonus, the fixture also stands to reduce user injury as it gives great mechanical advantage and no longer requires the user to grip and rotate the whole assembly.
