Patent ID: 6408514
Filing Date: 2002-06-25
Classification: B21F,B65B,B68G,F16F,Y10T

Abstract:
A method of forming a string of pocketed compound nested coil springs, the method comprising the steps of:forming a plurality of individual first coil springs each of a first uncompressed height and having a longitudinal axis; orienting each of the first coil springs with its longitudinal axis at a first inclination; forming a plurality of individual second coil springs each of a second uncompressed height which is greater than the first uncompressed height of the first coil springs, each of the second coil springs having a longitudinal axis extending between spaced terminal coils thereof; aligning the longitudinal axes of each of the first coil springs with one of the second coil springs; nesting each of the first coil springs into one of the second coil springs by passing the first coil spring into one of the terminal coils of one of the second coil springs and thereby forming a nested spring unit; compressing each of the first and second coil springs; folding an elongate sheet of fabric about a longitudinal fold line into two plies of fabric joined by the longitudinal fold line; inserting one of the first and one of the second coil springs between the plies of the folded fabric; wherein the nesting of each of the first coil springs into one of the second coil springs occurs after the inserting between the plies of the folded fabric; and forming an individual pocket in the fabric around each of the nested spring units, wherein the individual fabric pocket is formed around each of the first coil springs prior to nesting it into one of the second coil springs.