초록 ▼

This invention relates to methods and apparatus for manufacturing shaped polymeric articles by substantially continuous vacuum forming. The method includes providing a sheet of hot polymeric material which is disposed onto a rotating belt having a mold impression. Vacuum pressure is applied to the p

This invention relates to methods and apparatus for manufacturing shaped polymeric articles by substantially continuous vacuum forming. The method includes providing a sheet of hot polymeric material which is disposed onto a rotating belt having a mold impression. Vacuum pressure is applied to the polymeric material through the belt so as to draw the hot polymeric material into intimate contact with the mold impression to form a patterned sheet portion and a remaining sheet portion. This method thereafter cools at least the patterned sheet portion below a heat deflection temperature of the polymeric material, forms the remaining sheet portion, and then cools the remaining sheet portion below the heat deflection temperature so that features other than the central pattern, such as nail and butt edges, can be mechanically worked into the polymeric sheet.

대표청구항 ▼

[ We claim:] [1.]1. A method of manufacturing a shaped polymeric article, comprising:(a) providing a sheet of extruded hot polymeric material that is above its heat deflection temperature;(b) disposing said sheet onto a rotating belt, said rotating belt including a mold impression therein and a plur

[ We claim:] [1.]1. A method of manufacturing a shaped polymeric article, comprising:(a) providing a sheet of extruded hot polymeric material that is above its heat deflection temperature;(b) disposing said sheet onto a rotating belt, said rotating belt including a mold impression therein and a plurality of apertures therethrough;(c) applying vacuum pressure to said hot polymeric material through said belt, so as to draw said sheet into intimate forming contact with said mold impression to form a patterned sheet portion and at least one lateral edge portion;(d) selectively cooling said patterned sheet portion below said heat deflection temperature of said polymeric material while leaving said at least one lateral edge portion at a temperature above said heat deflection temperature;(e) further forming said at least one lateral edge portion;(f) cooling said at least one lateral edge portion below said heat deflection temperature to produce a relatively continuous shaped sheet; and(g) severing a length of said shaped sheet to produce said shaped polymeric article.