SELF-MIXING SYRINGE
A vacuum-sealed syringe able to internally mix contents autonomously
Summer 2024
Testing the internal propeller with clear shampoo (viscous fluid) and red food dye to visualize mixer effectiveness.
Features:
The Propeller
Non-captive stepper motor moving propeller shaft rotationally and translationally
Hard stop on shaft when propeller reaches its housing
The Plunger
Plunger adapter housing the propeller and syringe ports
Two o-rings embedded in plunger adapter as a rotary seal on propeller shaft
Rubber stopper vacuum-seals the plunger with inner walls of syringe
The Ports
Two ports— one for refilling syringe and one for silicone/viscous fluid extraction
Check valves on each port direct fluid flow to avoid leakages
Plunger adapter flush with base of syringe and ports (left), plunger raising as water enters injection port (right)
Objective: Design an airtight cartridge that automatically mixes viscous silicone and a thinner prior to a mold injection to reduce user engagement and boost manufacturing efficiency.
Constraints: Must hold vacuum, must mix contents thoroughly, and must eliminate pre-injection setup.
Steps of autonomous actuation
Cross-sectional view of cartridge (sketch)
Front view of plunger adapter
Future Work and Applications
The next iteration of this prototype can be fitted into a frame to be fully integrated into the injection workflow, streamlining manufacturing and operational processes. In pharmaceutical applications, the syringe could be scaled down, simplifying medication administration. Other applications for a self-mixing syringe include enhancing laboratory workflows, improving precision in various formulations, and facilitating on-demand mixing in diverse industries.