Mattress

Abstract

A mattress comprises a sealed outer casing within which is mounted a resilient support formed by a composite foam core. At least an upper portion of the resilient support is formed by a visco-elastic foam. A vent is provided in a side wall of the casing and is covered by a filter which prevents ingress of bacteria into the cover. A flap is mounted on the cover and in use extends down over the vent to prevent the filter being damaged by fluids.

1 . A mattress comprising an outer casing within which is mounted a resilient support, characterised in that the support is sealed within the casing and said casing has an air vent in a side wall of the casing.  
     
     
         2 . A mattress as claimed in  claim 1  wherein at least an upper portion of the resilient support is formed by a layer of visco-elastic foam.  
     
     
         3 . A mattress as claimed in  claim 1 , wherein a filter is mounted across the air vent to prevent the ingress of bacteria to an interior of the casing.  
     
     
         4 . A mattress as claimed in  claim 3 , wherein the filter has pores for through-passage of air, said pores being sized to trap any particle greater than 1 micron in size.  
     
     
         5 . A mattress as claimed in  claim 1 , wherein a flap is mounted on the casing, the flap being fixed to an exterior of the casing above the vent and extending downwardly over the vent, a free edge of the flap defining with the casing an opening for through passage of air to and from the vent.  
     
     
         6 . A mattress as claimed in  claim 1 , wherein at least portion of the resilient support has a profiled area comprising projections and hollows at an upper surface of the resilient support.  
     
     
         7 . A mattress as claimed in  claim 6  wherein said projections have a flat-topped pyramid shape.  
     
     
         8 . A mattress as claimed in  claim 6 , wherein said profiled area is at a lower end of the resilient support forming a heel support region of the resilient support.  
     
     
         9 . A mattress as claimed in  claim 2 , wherein the visco-elastic foam has a density in the range 60-95 kg/m 3 .  
     
     
         10 . A mattress as claimed in  claim 9  wherein the density of the visco-elastic foam is about 85 kg/m 3 .  
     
     
         11 . A mattress as claimed in  claim 1  wherein the resilient support includes a bottom layer of a combustion modified high resilient foam and a top layer of visco-elastic foam.  
     
     
         12 . A mattress as claimed in  claim 11  wherein the resilient support further includes an outer frame mounted about a side of said layers forming an endless side margin about said layers, said outer frame being formed of a high index foam.  
     
     
         13 . A mattress as claimed in  claim 1  including a composite resilient support having a laminated core with a rectangular bottom layer and an associated rectangular top layer superimposed on said bottom layer, a top face of the bottom layer engaging and adheisively secured to a complementary bottom face of the top layer, said bottom layer being formed of a combustion modified high resilience foam and said top layer being formed of a visco-elastic foam, said layers being of equal depth, said core being encircled by an outer frame formed of a high index foam which extends about the side faces and end faces of the core and being adhesively secured thereto, a sealed casing mounted about said core, said casing being formed of an elastic material stretched about the core with overlapping seams of the cover being welded together to form a sealed enclosure about the core, an opening in said casing forming a vent to allow air passage between an interior and an exterior of the casing, a filter mounted across the vent, and a flap mounted on the casing covering the vent and being fixed to said casing about a periphery of the flap above and at each side of the vent leaving a downwardly facing opening between a lower end of the flap and the casing for air passage to and from the air vent.  
     
     
         14 . A mattress comprising an outer casing within which is mounted a resilient support, at least an upper portion of the support being formed by a layer of visco-elastic foam, the support having a lower end forming a heel support region of the support, an upper surface of said heel support region being a profiled area of projections and hollows.  
     
     
         15 . A mattress as claimed in  claim 14  wherein the projections have a flat-topped pyramid shape.  
     
     
         16 . A mattress as claimed in  claim 14  wherein the support is sealed within the casing and said casing has an air vent in a side wall of the casing.  
     
     
         17 . A mattress as claimed in  claim 16  wherein a filter is mounted across the air vent to prevent ingress of bacteria to an interior of the casing.  
     
     
         18 . A mattress as claimed in  claim 16  wherein a flap is mounted on the casing, the flap being fixed to an exterior of the casing above the vent and extending downwardly over the vent, a free edge of the flap defining with the casing an opening for through passage of air to and from the vent.  
     
     
         19 . A mattress comprising an outer elastic casing within which is mounted a resilient support, at least an upper portion of the support being formed by a layer of visco-elastic foam having a density of about 85 kg/m 3 .  
     
     
         20 . A mattress as claimed in  claim 19  wherein the resilient support has a laminated construction including a rectangular bottom layer and an associated rectangular top layer superimposed on said bottom layer, a top face of the bottom layer engaging and being adhesively secured to a complementary bottom face of the top layer, said bottom layer being formed by a combustion modified high resilience foam and said top layer being formed by the layer of visco-elastic foam.