IMPROVED METHOD AND APPARATUS FOR THE PREPARATION OF FOAMED STRUCTURES

摘要

This invention is directed to a method and an apparatus for the preparation of a flexible polyurethane foam. For the method, a polyurethane foam forming mixture is provided, passing said mixture to a dispensing trough (11) wherein partial foaming takes place, the dispensing trough (11) discharging to a moving trough (28) wherein the foam forming mixture expands and cures to form a flexible polyurethane foam. The inventive method is characterized by providing means (16a-16d) for maintaining a generally uniform temperature across the mixture as the mixture passes from the dispensing trough (11) to the moving trough (28) by altering the internal configurations of the dispensing trough (11). The apparatus comprises in cooperative combination means to supply a foamable foam forming mixture of polyurethane components to a dispensing trough (11) wherein the foam forming mixture partially foams and is discharged to an open topped moving trough (28) wherein the foam forming mixture foams and cures to a flexible polyurethane foam. The inventive apparatus is characterized by comprising a means (16a-16d) within the dispensing trough to provide a generally uniform temperature along a cross sectional configuration of the foaming mixture as the mixture passes to the moving trough (28). The flexible polyurethane foam produced by the method and from the apparatus of this invention is useful in cushioning applications such as, for example, mattresses and seat cushions.