Abstract:
A method and apparatus for recycling scrap mineral fibers (42) having an organic binder coating in a highly stirred glass melter (16) wherein the organic binder coating is decomposed by applying heat. Carbon from the organic binder coating is oxidized on the surface of the glass melt (17). After oxidizing the carbon, the glass fibers are dispersed into the melt. Residual carbon may be oxidized after inclusion in the melt. Purified glass suitable for forming glass fibers is further processed by conventional glass fiber forming equipment. The method may also include the step of pre-processing the glass fiber scrap by shredding or pulverizing to facilitate feeding the glass fiber scrap to the highly stirred glass melt. The apparatus according to the present invention is preferably a stirred melter (16) having electrical joule effect heating. An impeller (22) in the glass melt stirs the melt at a high rate of speed to provide a draw down effect pulling fibers into melt.
Abstract:
A mold assembly support (10) is disclosed for providing a self-aligning thermally stable mold support in a glass sheet forming system (12) wherein a reference point within the glass sheet heating furnace (14) is connected by vertically extending piers (64) to a geometric frame of reference (16) outside the furnace (14). The mold assembly support (10) includes a frame (40) including mold registering members (52, 54) which define a stable thermal reference point within the furnace which is maintained in an unchanging relationship with respect to the geometric frame of reference (16) located beneath the furnace (14).
Abstract:
Apparatus (20, 120) for forming a heated glass sheet G is disclosed as including a vacuum mold (22, 22a, 122, 122a) having a full surface (24, 24a, 124, 124a) against which a peripheral mold (26, 26a, 126, 126a) presses the glass sheet periphery and with which at least one vacuum reservoir (32, 33) is communicated within the interior of the sealed glass sheet periphery to form the glass sheet to the shape of the vacuum mold surface. Valving (38) of a vacuum system (28) is preferably operable to provide the vacuum impulse in two stages with an initial limited extent of vacuum and a subsequent greater extent of vacuum by communication first with one vacuum reservoir (32) and subsequently with another vacuum reservoir (33). Different embodiments of the vacuum mold have the vacuum mold surface facing upwardly and downwardly with convex and concave shapes. Glass sheet shapes including straight line elements such as cylindrical and conical bends as well as shapes including curvatures in transverse directions and inverse curvatures can be effectively provided by this vacuum impulse forming.
Abstract:
A quench station (14) including apparatus for quenching a heated glass sheet (G) conveyed by rolls (22) of a roller conveyor (20) is disclosed as including upper and lower sets of blastheads (32) having outlets (34) that are positioned closer to the conveyed glass sheet than the conveyor roll radius (R) and which are oriented and sized to provide highly efficent quenching such as during heat strengthening or tempering. These blasthead outlets (34) are preferably round and the blastheads (32) are vertically aligned with each other to provide aligned locations (36) of impingement with the oppositely facing surfaces of the glass sheet. A set of upper roll mimics (38) of the preferred embodiment is located above the conveyor rolls (22) in a vertically aligned relationship provide symmetry that results in uniform quenching of both glass sheet surfaces.
Abstract:
An apparatus for heating, bending and quenching glass sheets (10) is disclosed as including a first platen (14) and a second platen (22). Both platens (14, 22) are deformable for bending a heated glass sheet (12) therebetween. A first heater (18) is integral with the first platen (14) and provides heat in close proximity to the heated glass sheet (12) during the bending to maintain an optimal glass bending temperature. Both platens (14, 22) have quench openings (20) for tempering the bent glass sheet with quenching gas.