Compact pneumatic pump ideas

[hpil]

Looking for ideas for a compact pneumatic pump module that includes a friction clutch (linear or z24) and and on/off drive connection (could be changeover catch or sliding cogs). I've got an idea which is 3l x 5l x 12l, but wondering if there are any genius ideas out there...

[mocbuild101]

I'm not quite sure if I understand what you're looking for, but these could be of interest: (both designed by @Sariel)

[hpil]

Not quite what I'm looking for, but thanks. Think I've now got a solution by separating out the pump, friction clutch and changeover catch and squeezing them into different parts of the model. In the process I discovered a li ear friction clutch doesn't have enough friction to turn the pump, so had to use a z24 friction clutch