Spring-loaded needle stroke mechanism

[Valeriya Volkov]

Hi guys,
I need help designing a lab jig to make the technicians work easier. Been wrapping my mind and imagination around it, but couldn't figure it out.

Basically, I need a medical needle (hollow) to have about a 1mm linear stroke when triggered. Imagine that it needs to pierce a thin sheet of plastic. So, it's best if there is a button or something to be pushed that causes that 1mm piercing stroke.

Problem#1: That same needle has either liquid or air pressure going through it, connected to a tube.

Problem#2: That same needle will sometimes be submerged in water.

Can anyone help me design something like that?

 

[SwinnyGG]

Sounds like you have air supply going to this apparatus already...

If you can use that air elsewhere, use a pneumatic cylinder to move the needle. Relatively simple.

 

[WKTaylor]

VV...

1.0-mm total stroke... or 1.0-mm + material thickness total stroke?

WHAT diameter needle and how long is the penetrating chamfered/sharpened tip?

How rapid [in-out] is the necessary/require rate/motion?

Just to make sure: this must be a single motion per trigger-pull... NOT... continuous motion per trigger-pull?

Low or high dynamic forces of penetration?

Suggest You look at 'tattoo' equipment, which extends/injects-ink/retracts needle above/below/above the skin, very fast. Perhaps that equipment could be adjusted for 'one-round per trigger pull' or 'multiple shots per trigger-pull' with precise liquid/gas dispensing.

Regards, Wil Taylor

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