Syringe Needle Cover - Design & Tooling

Background

The client requested a cover to fit onto a syringe.  The function of this cover is to protect the medical practitioner from an accidental prick of the needle.   It was to aid the AIDS awareness as well.  The cover needed to enclose the needle when not used but expose the needle when required to inject.  Once the injection process is complete and the needle is removed from the patient, the needle needed to be closed by the cover again.

Conclusion:

I designed a cover from the conceptual sketches.  The cover would be made in two parts, made from a rigid plastic tip fitted to the elastomer bellow section.  The plastic tip protected the dangerous needle tip.  The elastomer part used the bellow and spring action to expose the needlepoint only when required.
 Samples were made, materials selected were a transparent PP and Kraton was selected for the elastomer section.
The initial design did not work well.  The elastomer section was too rigid and bellowed differently from what was expected.  Four slits were made to the sample.  The bellow section then functioned as four legs, bellowing correctly.
The customer approved the samples, but requested that the design to be smaller and more compact.  It was decided that the cover to be made from plastic featuring collapsible hinges fitted to the legs.

Images:

• Syringe Needle Cover