Spring mattress with uniform tension - having single polymer thread crisscross on frame with tension adjustable by screws

摘要

A spring mattress has a frame and plastic spring elements which are made of one continuous thread. The elements criss-crosses to and fro, the continuous thread being fixed to the frame only at the ends. The cross elements themselves are not bonded. Suitable polymers for the thread are polyamide, polyester and polypropylene of 1-5mm dia. When loaded non-uniformly e.g. by a human body, the tension in the spring is distributed uniformly over the whole mattress, the 'hardness' of the bed can be adjusted.