| 摘要 |
<p>A method for continuous foaming of a panel (2) of the type comprising outer layers (3A, 3B) of web material between which an intermediate layer (5) of insulating foam is interposed, comprises the steps of: supplying a first (4A) and second (4B) web material, which are precursors of said outer layers (3A, 3B), according to respective mutually converging directions (D1, D2) to a dispensing station (SE) of reactive mixture intended for generating the intermediate layer (5) of insulating foam; maintaining the first (4 A) and second (4B) web materials oriented according to planes that tilt mutually and converge downwards so as to bound a V-shaped hopper zone (6); defining between the web materials (4A, 4B) a calibrated slit (7) in the bottom of the hopper zone (6) for dragging the reactive mixture with squeezing and distribution to the end edges of the web materials; filling at least partially the hopper zone (6) with the reactive mixture for simultaneously wetting the two web materials (4A, 4B) advancing downwards; advancing continuously the two web materials (4A, 4B) along a very steep, vertical or very tilted portion of path (Ty), dragging the reactive mixture progressively downwards; supplying, along the vertical portion a guiding and resting action to said first (4A) and second (4B) web materials so as to advance the first (4A) and second (4B) web materials substantially mutually parallel at a controlled mutual distance; diverting, downstream of the portion (Ty) of vertical or very tilted path, the web materials (4 A, 4B) along a successive curved portion (Tc) of foaming path; guiding, downstream of said curved portion (Tc), said first web material (4A) along a first resting and guiding plane (Pi), that is horizontal or almost horizontal, and said second web material (4B) along a second resting and guiding plane (P2), tilted with respect to the first resting and guiding plane (Pi), such that the first (4A) and second (4B) web materials advance in a mutually divergent manner at a growing distance from one another along a transition portion (Tt) of the foaming path along which a guided expansion of said reactive mixture develops; conveying, and providing a resting action to the web materials (4A) and (4B), with the interposed expanding foam, by means of two parallel belt conveying devices (8A, 8B), along a substantially horizontal final portion (Tf) of path to enable the foam reaction to be completed and the shape of the foam to be stabilised. An apparatus for implementing the aforesaid method is also disclosed.</p> |
