Method for manufacturing enhanced foam thermoplastic products

A process for forming a combined wire retaining and spring assembly support plate having a generally rectangular shape defined by four adjacent edges, said process comprising the steps of:

• A. extruding an enlarged, substantially flat panel formed of foamed thermoplastic material and dimensioned for being positioned in supporting, underlying engagement with a mattress inner spring assembly;
• B. forming a first elongated, longitudinally extending enhanced zone along a first edge of the panel, said first enhanced zone being spaced inwardly from said first edge, and thereby forming a first spring retaining section between the first enhanced zone and the first edge of the panel;
• C. forming a second elongated, longitudinally extending enhanced zone along a second edge of the panel, said second enhanced zone being spaced inwardly from said second edge, and thereby forming a second spring retaining section between the second enhanced zone and the second edge of the panel;
• D. positioning a fully constructed mattress inner spring assembly on said enlarged, substantially flat panel with the outer peripheral edge of said inner spring assembly being positioned inwardly of the first and second enhanced zones;
• E. arcuately pivoting the first spring retaining section relative to the first enhanced zone for engaging the first spring retaining section with the inner spring assembly positioned adjacent said first edge;
• and
• F. arcuately pivoting the second spring retaining section relative to the second enhanced zone for engaging the second spring retaining section with the inner spring assembly positioned adjacent said second edge, thereby securely mounting the inner spring assembly to the supporting panel for providing spring retaining interengagement therewith.