Abstract: A fluid-filled bladder-type mattress includes a plurality of panels periodically disposed at oblique angles between upper and lower surface members of the bladder mattress for suppressing motion. In one preferred embodiment, a single bladder chamber is filled with a liquid fluid, and panels comprising a plurality of planar membrane members are bonded along angular lines alternately and at oblique angles to the upper and lower surface members of the bladder in a herringbone bonding pattern to provide an open inner structure promoting wave energy dispersion and dissipation. A mattress embodying the invention minimizes horizontal motion and fluid wave propagation.

Abstract: Apparatus for forming a swimming pool cover or similar article having relatively large transverse dimensions by joining a plurality of elongated pieces of heat sealable material together is disclosed. The apparatus includes a working bed, and means for dispensing first and second pieces of heat sealable material onto the bed so that a marginal portion of the first piece is exposed. The apparatus folds the exposed marginal portion of the first piece over a corresponding marginal portion of the second piece, and the marginal portions are heat sealed together to form a single wider piece of material. The wider piece of material is drawn from the bed and stacked and then returned to the dispensing means for adding another elongate piece to the width of the material, eventually forming a piece of material sufficient to cover the entire pool.

Abstract: A waterbed is disclosed which has a frame with a self-supporting bulkhead forming a safety lining. The bulkhead comprises two connected wedge-shaped members which are made of pliant material, and are held in place by a resilient membrane. A base member is anchored to a rigid backing or baseboard. A unitary resilient nonporous membrane is fastened to the edges of the baseboard and drawn tautly across the baseboard over the base member. A lateral member rests upon the base member and is sealed to the underlying membrane at the inwardly disposed margin of the lateral member, which is outboard of the inner boundary of the base member. The lateral member comprises a polyvinylchloride or like nonporous thermoplastic tube enclosing a polyurethane or like pliant member. The waterbed mattress comprises a bladder having a wedge-shaped margin conforming with the inwardly disposed wedge-shaped edge of the frame bulkhead.

Abstract: Apparatus and method for forming a bead on the border of a swimming pool liner or similar article of plastic sheet material. The plastic sheet is located so that a portion of the border thereof underlies the elongate heat sealing member of a heat sealing apparatus. An elongate strip of bead material is dispensed beneath the heat sealing member and underneath the border of the plastic sheet underlying the member so that the border overlaps the strip. The outer edge of the bead material is compressed by engaging it with a transverse moving member adjacent the edge of the border to provide curvature to the material. The heat sealing member is then motivated downwardly into contact with the portion of the border of the plastic sheet underlying the member to heat seal the border to the bead material. The curvature of the bead material provides excess sheet material where the heat sealing takes place to minimize the formation of a tear line between the bead material and the plastic sheet.

Abstract: Apparatus for forming a swimming pool cover or similar article having relatively large transverse dimensions by joining a plurality of elongated pieces of heat sealable material together is disclosed. The apparatus includes a working bed, and means for dispensing first and second pieces of heat sealable material onto the bed so that a marginal portion of the first piece is exposed. The apparatus folds the exposed marginal portion of the first piece over a corresponding marginal portion of the second piece, and the marginal portions are heat sealed together to form a single wider piece of material. The wider piece of material is drawn from the bed and stacked and then returned to the dispensing means for adding another elongate piece to the width of the material, eventually forming a piece of material sufficient to cover the entire pool.

Abstract: An apparatus for bonding an elongate reinforcing strip of flexible material to an envelope, comprising a frame, a first stationary head assembly, a second head assembly, cooperating opposed drive roll means on said first and second head assemblies, reel means mounted on said frame and a heat gun mounted in said second head assembly.