Double wall mattress for waterbeds

Claim 1

In a mattress for a waterbed, wherein said mattress includes a bladder for containing a quantity of water, and access means for filling and draining said bladder, the improvement wherein said mattress includes a first bladder for containing a quantity of water, and a second bladder for containing said first bladder, said first bladder being fully within said second bladder and completely filling said second bladder, and first access means for providing access to said first bladder for filling and draining said first bladder, and second access means for providing access to the interior of said second bladder, the arrangement being such that said first bladder provides support for a person lying on the mattress and said second bladder provides a second bladder to contain leakage from said first bladder, said first access means including a neck, and a flange on one end of said neck for fixing said neck to a bladder, said first bladder defining a hole therein aligned with said neck, said flange being disposed between said first bladder and said second bladder, the further improvement wherein said second access means includes a neck, and a flange on one end of said neck for fixing said neck to a bladder, said second bladder defining a hole therein receiving said neck therethrough, said flange being sealed to said second bladder around said neck, said second bladder defining a second hole therein aligned with said neck of said first access means, said neck of said first access means extending through said second hole in said second bladder, said flange of said first access means being sealed to both said first bladder and said second bladder so that said first bladder and said second bladder are retained in fixed relation to each other while said first bladder is free to conform to the interior of said second bladder.