초록 ▼

A simple and inexpensive method and apparatus for molding a peripheral frame around a sheet or grid of thermoplastic material to produce a framed panel. A peripheral frame, preferably of structural foam or the like, is injection molded about a thermoplastic sheet or grid of panel-forming material wh

A simple and inexpensive method and apparatus for molding a peripheral frame around a sheet or grid of thermoplastic material to produce a framed panel. A peripheral frame, preferably of structural foam or the like, is injection molded about a thermoplastic sheet or grid of panel-forming material which has been previously drawn or stretched at a temperature which orients the molecules of the polymer, i.e., below the glass transition temperature of the polymer, Tg. Either during the frame molding process, or subsequent thereto, the panel-forming material is heated sufficiently to cause the material to shrink or revert toward its prestretched condition so as to tension the panel-forming material within the frame. Elastomeric sealing devices are disclosed for sealing the mold during injection of the frame-forming material and locator fingers are provided to position a grid-like panel-forming material prior to initiation of the molding process. By the utilization of structural foam molding techniques, a panel of thermoplastic material may be integrally-molded and tensioned within a rigid frame to produce a framed panel of any size for use as a barrier, a fence, a guard, a closure, a seat or bedding support, a filter member or other such applications.

대표청구항 ▼

An apparatus for making a framed panel comprising: a pair of molding members together defining a peripheral frame-forming mold cavity; means for moving at least one of said molding members to open and close said mold cavity; means to position peripheral portions of a thermoplastic panel-forming mate

An apparatus for making a framed panel comprising: a pair of molding members together defining a peripheral frame-forming mold cavity; means for moving at least one of said molding members to open and close said mold cavity; means to position peripheral portions of a thermoplastic panel-forming material within said mold cavity, central panel portions of said panel-forming material being molecularly oriented; means to inject a molten frame-forming material into said mold cavity and to solidify said frame-forming material so as to capture said peripheral portions of said panel-forming material within a rigid frame; and means to heat said central portions of said panel-forming material sufficiently to cause said panel-forming material to shrink and thereby tension said panel-forming material within said frame.