Helical spring string for spring suspension of bedding mattress, has retention pockets, each containing two helical springs that are connected via central coil having smaller diameter and produced with same metallic wire

摘要

The string has retention pockets (3), each containing two helical springs (5, 6) that are connected with each other in series. The helical springs are connected with each other through a central coil having smaller diameter. Each helical spring is produced from a same metallic wire without discontinuity. The helical springs in the same pocket have same or different stiffness.