Ford announced yesterday that it was working with 3M to make powered air-purifying respirators (PAPRs) to help with the response to COVID-19. A PAPR is a respirator that uses a fan to pull possibly contaminated air through a filter and pushes it to a sealed face mask worn by the first responder or medical professional.
The most important part of these systems is the filtration (and seal), which has given Ford some flexibility to design a system that it can make using largely in-house components.
Bozi Tatraveic, parts-interchangability expert, broke down Ford's plan for Road and Track . The heart of the system, beyond the 3M filter, is a blower motor sourced from F-150 ventilated seats. Ford would likely use 100s of thousands of these per year, so should have some around along with the ability to quickly get more.
The fans are 12-volt operated, since they're in a car, which means that they can run on a rechargeable battery pack like that used for cordless power tools. That helps keep the system small, portable, and easy to maintain and source.
According to the report, blower fans like these can operate using as little as 0.53 amps and move around 15 cfm of air. The original 3M blowers move 6.7-7.8 cfm of air depending on settings, but the Ford blower speeds could be reduced using a number of simple controls.
Using conventional, easily obtained and charged, power drill batteries, and assuming that half-speed generates half the airflow and uses half the current, the blowers could run up to 10 hours, which is on par with the original 3M high-capacity units.
The masks, and sealing everything, would be more complex, but Ford has extensive experience in 3D printing that it could likely transfer, and 3M may be able to ramp up that part of production on its own, ensuring more respirators make it to the front lines and make healthcare workers safer and more comfortable.