| 摘要 |
<p>Earplugs produced by extrusion of a foamable polymer through an extrusion head opening (14), are severed and shaped to produce a largely symmetric rounded end (27, 28) and/or compression bands (190, 192, 204) for stiffening. Severing of an earplug at the extrusion head is accomplished by two or more cutting blades (50, 52) that move in largely opposite directions across one another to provide a symmetric cut that foams into a largely symmetric rounded earplug end. Compression bands are formed along the earplug to stiffen it, by two or more compression dies (221-224) spaced about the axis of the earplug. An earplug with a stiffening sleeve (116) that is surrounded by a foam covering (124) and that is filled with a string (122) of the same foam, is severed so at the opposite ends of the earplug the covering ends (160) and string ends (162) are rounded even though the sleeve end (164) is cut perpendicular to the earplug axis (166).</p> |
