Filtered Air Face Shield by OTandAT

Last crawled date: 3 years ago

This is an upgrade of an earlier face shield I designed. This mask delivers filtered air to keep the shield from fogging as well as supplying a flow of filtered air (99% of 0.3um particle sizes) over the eyes and mask. Filters used are cut from KX Filter melt-down polypropylene electro-charged fabric. Once a small square of filter is cut, I melted a small hole in the middle for the bolt that sandwiches the filter between the lid and cover. The 12 volt dc brush-less fan is from DFRobot (FIT0241). A switch and four double AAA battery packs wired in series supply the 12 volts dc. Once the fan output is placed in the holder in the box you will need to drill a bolt hole and add a bolt to secure the fan (see picture). The bolt can't be too long to interfere with the box lid. This unit will run for a few hours before the batteries and filter material need changing. This can use a standard poly-carbonate face shield (Hobart and others...) The tear drop plugs (need 5) fit through the keyhole and turn to lock the shield and front piece together. There is a belt clip on the back of the box made in ABS that was just super glued on and seems to work. The box pictured has an extra switch hole that was not used and is not in the box design posted. The tubing was medical vent tubing. Most of this is PLA except the belt clip, box top and filter holder that were printed with ABS.