Ford Is Using Seat Ventilation Fans to Build Respirators
Ford today announced that it has partnered with 3M to build Powered Air Purifying Respirators (PAPR) in response to the COVID-19 pandemic. These breaths are often referred to as positive-pressure masks because they expel contaminated air, pull it through a filter, and then push it into a closed mask with an air blower.
Ford helps provide parts from their parts bin to build respirators. The design, released by Ford uses 3M filters that draw air into the blower motor provided by the F150 and then push the tube into the closed mask on the user’s face. The blower motor is made from the F150’s front seat assembly and is usually used as part of a ventilated seat option. These motors are compact and run at 12 volts in the car, so they can be used with a battery pack if they are portable.
Seat blower motors may not seem like the first choice, but they really match the blowers you see in such respirators. According to Delta Group, seat blowers run from 9 to 16 volts. This allows the gas to be produced at 14 to 19 CFM. By comparison, the 3M produces between 6.7 and 7.8 CFM depending on the motor configuration of the TR-800 system, making the seat blower a close match. The power of the seat blower can be adjusted by various methods, such as PWM control, to provide air to the same purpose-built respirator blowers.
This airflow rating means that blower motors may not be a good choice for basic HVAC systems in cars. These units can produce hundreds of CFM ventilators. Size is also a factor. Seat blowers are usually 3×3 or 4×4 inches wide and less than an inch wide. A basic HVAC blower motor is often 6×6 inches wide and more than six inches high.
Ford plans to use power tool batteries to operate the respirators. Based on their sketches, they seem to be using the equivalent of the DeWalt DC9071 12-Volt. This battery is rated at 2.4 amps per hour, which allows you to get an approximate estimate of working time using the time = current / amps formula. In this case, we take 2.4 amp hours and divide it by 0.5 amps from the above blower rating and give it a little run time in five hours.
Since these blowers only need to be operated at half speed, the run time is likely to double, extending to 10 hours. These numbers are comparable to utility-built respirator battery packs that take four to six hours for standard units and eight to 12 hours for high-capacity units.
The great thing about using off-the-shelf parts is that most of the parts needed to assemble these respirators come in very large quantities. Seat blower motors can pull Ford off the shelf and request more from suppliers if needed. Drill battery packs use a standard interface, available from original equipment manufacturers and aftermarket sources.
Ventilated seats are now so widespread that most manufacturers take blowers from the same supplier. The biggest is Genther. They have previously supplied parts for many Ford vehicles and manufactured blowers for various manufacturers. Cars like the Jeep Grand Cherokee use Genterm blowers similar to those used in the F-150, so other automotive manufacturers can join Ford by making or supplying parts on their shelves.. The masks may need some work, but Ford has already begun to use their resources at their advanced manufacturing facility in Redford, Michigan.