Chemical Splash Goggles: One Sealed Lens in a Moulded Rubber Frame (Hirschmann, 1954)

Goggles for work with corrosive liquids. One clear plastic lens covers both eyes and sits sealed all round in a soft moulded rubber frame that seals against the face. The version for gas and corrosive liquids has no vent holes at all, and the strap passes through tabs outside the lens, so nothing can leak through or around the part you look through. Result: chemical splash goggles with a lens you can pull out and replace, and a strap pull shared evenly between lens and frame, so neither warps. Source: J. B. Hirschmann, US Patent 2,680,846 (1954), Fig. 4 version. Unknown: sizes, the rubber compound, the strap material and how the frame is moulded. Ours: the mould; the patent tested a cellulose acetate lens. Picture: patent drawing.