23/04/2020
While under coronavirus quarantine, I thought it would be interesting to design a ventilator or respirator made from household items. The components in this concept could easily be made more advanced and mass produced using sixaxis robots. This is the latest iteration of my design for a DIY mixed air and oxygen tent or facemask respirator. It works through the Hering-Breuer reflex, as in the Kiss-of-Life and CPR (Cardio Pulmonary Resuscitation.) Outside lung pressure can be increased to whatever helps the occupant breath freely, by opening or constricting the vented air mixture in my attached plans. A computer fan maintains high ambient pressure for the occupant’s environment, though an oil-free DC tyre inflator on my “fag packet” sketch can be substituted. The valves, connectors, double-walled soundproofing and almost all the hardware can be 3D printed. However, 3D printing is not essential. Everything is available around the average household and stuck together with duct (gaffer) tape. Oxygen enhancement comes from the sealed electrolysis of water with a non-salts (salts produce chlorine gasses) household electrolytes that contain potassium hydroxide, chemical symbol KOH, found by reading the labels on oven or drain cleaning products. There are plenty of poisonous gasses that might be ingested in the air (e.g. carbon monoxide) but it is mainly oxygen that is scavenged by the lungs. Though a hydrogen air mix is breathable, as it is a fairly inert gas, it passes through the lungs along with all the other harmless gasses in atmospheric air, without consequence. However, because hydrogen is too explosive within any part of the system, this is entirely vented to the outdoors and should be continually burnt off with a pilot flame. The final stages in both my diagrams are optional and instead, pressure can be kept by adding or taping over the “safety” vent holes in the “bubble bed” sleeping bag or exchanging the valve-fitted bottle tops with different diameter holes, in my clear PET (Poly Ethylene Terephthalate) “pop” bottle facemask, to the level needed to engender comfortable breathing. Gaffer taping and sealing the sleeping bag fabric with plastic sheeting may also be unnecessary, depending on the material it is made from or the sleeping bag replaced altogether and a homemade box used instead. The electrodes in the electrolysis unit must be inert metals. Any British hallmarked silver (or at a push gold) will do, such as silver spoons or straitened gold bangles, for example. Copper is also a noble metal but it is biologically toxic, whereas the colloidal water by-products of silver or gold electrolysis are potable (provided the added electrolyte is non-toxic or at very low levels), pro-biotic, anti-viral and anti-bacterial. For the sake of peace-and-quiet when sick, the transformer, electric motor and electrolysis unit, can all be enclosed in laminate walled boxes made from any combination of polystyrene sheets, corrugated cardboard, tin foil, lino and, or plywood etc., available in the house, garage or shed. The bubble-bed design or as an alternative, a person sized laminated box with observation windows, is more comfortable for the user but a clear 1 litre plastic (PET) bottle facemask can also be used instead. These ideas can easily be improved for production manufacturing using robots. For example, the electrolysis unit in the “homemade” version here, can be made by far more effective with specific tooling and by using industrial line robotics, this concept can be an effective but still simple design for mass-production.
