Method for making a spring core for a mattress or for seating products
AssigneeNV Bekaert SA
InventorBert VANDERBEKEN
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Abstract
A method to manufacture a steel wire spring core for a mattress or for seating is described, which comprises the steps of providing a carrier comprising steel wire; repeatedly cold coiling a steel wire spring from steel wire taken from the carrier; and connecting a series of the coiled steel wire springs to each other. The steel wire has a diameter d between 0.8 and 4.5 mm; and has a drawn pearlitic microstructure. The steel wire comprises a steel alloy having a carbon content between 0.35 wt % and 0.85 wt %. The steel wire on the carrier has a ratio—expressed as a percentage—of the yield strength Rpo 2 (in MPa) over the tensile strength Rm (in MPa) higher than 85%.
Claims15
A method to manufacture a steel wire spring core for a mattress or for seating, comprising the steps of
- providing a carrier comprising steel wire;
- repeatedly cold coiling a steel wire spring from steel wire taken from the carrier, and
- connecting a series of the coiled steel wire springs to each other;
- wherein the steel wire has a diameter d between 0.5 and 4.5 mm;
- wherein the steel wire comprises a steel alloy, wherein the steel alloy has a carbon content between 0.35 wt % and 0.85 wt %;
- wherein the steel wire has a drawn pearlitic microstructure;
- wherein the steel wire on the carrier has a ratio—expressed as a percentage—of the yield strength Rp0.2 (in MPa) over the tensile strength Rm (in MPa) higher than 85%.
Dependencies are inferred from the claim text.