Shatterproofing of fluorescent lamps

摘要

A method of shatterproofing a fluorescent lamp having a glass envelope by extruding a polymeric coating over the lamp envelope so that it intimately embraces substantially all of the external contours of the lamp, including its glass envelope and end-ferrules thereby increasing the hoop strength of the glass envelope. The lamp is passed through an air lock into the main lumen of a crosshead which extrudes a cylinder of hot plastic that is radially drawn inward toward the lumen axis by an applied vacuum. A continuous chain of encapsulated lamps emerges from the crosshead that then may be cut apart to reveal individually completely encapsulated lamps.