This is optimised to fill bottles in an oxygen-free and sanitary manner.
The filler is compatible with stubbies, king browns, PETs, and even cans! (If I shortened the dip tube a bit, it would be, anyhow)
The process is automated with solenoids and a small industrial PLC in the cabinet. A bit overblown, but I fished it out of the bin at work, so we might as well put it to good use!
So the process is:
Start vacuum pump – the bottle is manually pressed up against the filler head. The filler head pad is silicone. The vacuum quickly builds up enough to hold the bottle by suction alone. Once a timer runs out, the platform automatically raises to clamp the bottle against the filler head. Once this is verified by the compression of the filler head springs, CO2 is let in to start the counter-pressure filling process. Shortly afterward the leak valve is opened to allow the pressure to drop and allow beer to enter. Once the bottle is filled, the platform is lowered, completing the process.
A fill is shown below.
Some further details:
These are the gas solenoids – one for vacuum, CO2, and vent. The test-tube looking thing is a PET blank from an old yeast vial – this is to capture any beer/foam before it gets into the solenoids/vacuum pump.
This is the finest drill ever made by human hands. It spent 11 years outside in the rain attached to the spit roast in its previous occupation as an auto-baster. The chuck needed a bit of lubrication, and the wasps inside were pretty unhappy when I fired it up, but now it’s back in action!
The attachment offers two degrees of freedom to allow it to track the motion of the scissor jack.
This runs an old Siemens S7-200 PLC. The manual mode is good for filling non-vacuum compatible containers – like PETs or cans.
The silicone filler head. This is completely coated with silicone (even the wooden looking parts) so the entire assembly can be removed, and boiled if necessary, for sanitation. I make my own silicone “paint” by diluting neutral cure in Shellite.
Standard refrigeration duty vacuum pump. I should get some more fittings so I don’t need the whole manifold in the middle.
The limit switch is mounted to the aluminium sheet. Once the springs compress, the platform raising operation is complete. I believe the springs on the filler head are from a 1984 Honda XR250 clutch. The other limit switch mounted in the middle is there in case some fool runs the system without a bottle. Otherwise the platform would collide with the dip tube and cause havoc.