Abstract: A method for forming a foamed innerspring unit is provided including releasably securing a plurality of coils to a jig, delivering a foamable reaction mixture to a tray and positioning the jig so that the ends of the coils extending away from the jig are spaced from the bottom of the tray so that the rising foam embeds the end of the coil. The process is repeated by releasing the foamed layer embedding one end of the coils, releasably holding the first foam layer with the ends thereof spaced from a tray having said foamable reaction mixture therein so that the second end of the coils is embedded a second foam layer. A mattress formed of a plurality of innerspring unit sections formed in accordance with the foregoing may be combined within a cover to define a mattress. By selecting the firmness of the coils of adjacent sections, regions of differing firmness can be provided in the mattress.

Abstract: A method for producing a foamed innerspring unit using a foamable reaction mixture that will provide a flexible foam using diphenylmethane diisocyanate and at least one polyol is provided. The process comprises the steps of preparing the foamable reaction mixture, spraying the foamable reaction mixture into a tray, loading an innerspring unit into the foamable reaction mixture containing tray and permitting the foamable reaction mixture to rise to form a foam that is at least partially adhered to the unit. The process is especially well suited to be carried out on a continuous conveyor. A novel foamed innerspring unit is also provided.