Mattress structure having a foam mattress core

Abstract

An elongated mattress core for a mattress structure includes a foam core having an upwardly-facing top surface, a bottom surface spaced apart from the top surface, and first and second elongated sides connecting the top and bottom surfaces. The foam core is formed to include a plurality of longitudinally spaced apart transverse slits extending downwardly from the top surface. Each slit terminates at a lower end spaced apart from the bottom surface by a first distance and extending transversely from a first slit end spaced apart from the first side of the foam core to a second slit end spaced apart from the second side of the foam core. Each adjacent pair of slits defines a foam column so that the foam core has a plurality of longitudinally spaced apart and transversely extending foam columns. Each foam column has a pair of generally vertical column side walls defining the slits. Each column side wall includes a shear coating having a low coefficient of friction so that each column can compress and decompress without drag forces resulting from frictional engagement with adjacent column side walls interfering with the compression and decompression.

We claim:  
     
       1. An elongated mattress core for a mattress structure, the mattress core comprising: 
       a foam core including  
       an upwardly-facing top surface,  
       a bottom surface spaced apart from the top surface, and  
       first and second elongated sides connecting the top and bottom surfaces, the foam core being formed to include a plurality of longitudinally spaced apart transverse slits extending downwardly from the top surface, each slit terminating at a lower end spaced apart from the bottom surface by a first distance and extending transversely from a first slit end spaced apart from the first side of the foam core to a second slit end spaced apart from the second side of the foam core, each adjacent pair of slits defining a foam column so that the foam core has a plurality of longitudinally spaced apart and transversely extending foam columns, each foam column having a pair of generally vertical column side walls defining the slits, each column side wall including a shear coating having a low coefficient of friction so that each column can compress and decompress without drag forces resulting from frictional engagement with adjacent column side walls interfering with the compression and decompression.  
     
     
       2. The mattress core of  claim 1 , wherein the shear coating includes a material having a low coefficient of friction received by at least one slit of the plurality of slits. 
     
     
       3. The mattress core of  claim 1 , wherein at least one foam column is formed to include a shallow second slit extending downwardly from the top surface and terminating at a lower end spaced apart from the bottom surface by a second distance and extending transversely from a first shallow slit end spaced apart from the first side of the core to a second slit end spaced apart from the second side of the core, the second distance being greater than the first distance. 
     
     
       4. The mattress core of  claim 1 , wherein the plurality of foam columns includes a foam first column made from foam rubber having a first indention load deflection and a foam second column made from foam rubber having a second indention load deflection, the second indention load deflection being different from the first indention load deflection. 
     
     
       5. The mattress core of  claim 4 , wherein the top surface of the first column is formed to include a transverse cut extending downwardly from the top surface so that the support and firmness characteristics of the mattress adjacent to the first column are different from the support and firmness characteristics provided by the first column before forming the transverse cut. 
     
     
       6. The mattress core of  claim 1 , wherein the foam core includes a frame including an elongated first foam side member having an inner side surface and an outer side surface spaced apart from the inner side surface and defining the first side of the foam core and an elongated second foam side member having an inner side surface and an outer side surface spaced apart from the inner side surface and defining the second side of the foam core, the slits extending transversely from the inner side surface of the first foam side member to the inner side surface of the second foam side member. 
     
     
       7. The mattress core of  claim 6 , wherein the frame includes first and second foam end members, each foam end member abutting both of the first and second foam side members and each foam end member engaging one foam column. 
     
     
       8. The mattress core of  claim 7 , wherein the first and second foam end members and the first and second foam side members each have an indention load deflection that is greater than the indention load deflection of the plurality of foam columns so that the mattress structure has greater firmness and support characteristics along the perimeter of the mattress. 
     
     
       9. The mattress core of  claim 1 , wherein the foam core includes longitudinally spaced apart head, shoulder, seat, thigh, and foot zones, each zone including at least one foam column, the foam columns of each zone being made from foam having a selected indention load deflection, the indention load deflection of the foam in each zone being selectable for each zone independently of the other zones. 
     
     
       10. The mattress core of  claim 9 , wherein one foam column of the foot zone includes an upper column portion having a selected first indention load deflection and a lower column portion beneath the upper column portion having a selected second indention load deflection greater than the first indention load deflection so that the lower column portion is firmer than the upper column portion and the mattress structure adjacent the foot zone provides generally similar support and firmness characteristics as the mattress structure adjacent the head, shoulder, seat, and thigh zones while also reducing the interface pressure adjacent to the heels of the user. 
     
     
       11. The mattress core of  claim 9 , wherein one foam column of each of the head, shoulder, and thigh zones are made from foam having a selected first indention load deflection and one foam column of the seat section is made from foam having a selected second indention load deflection that is greater than the first indention load deflection so that the support and firmness characteristics of the mattress structure adjacent to the seat zone is greater than the support and firmness characteristics of the mattress structure adjacent to the head, shoulder, and thigh zones. 
     
     
       12. An elongated mattress core for a mattress structure, the mattress core comprising a foam core including an upwardly-facing top surface, a bottom surface spaced apart from the top surface, and first and second elongated sides connecting the top and bottom surfaces, the foam core being formed to include a plurality of longitudinally spaced apart transverse slits extending downwardly from the top surface, each slit terminating at a lower end spaced apart from the bottom surface by a first distance and each slit extending transversely from a first slit end spaced apart from the first side of the foam core to a second slit end spaced apart from the second side of the foam core, each adjacent pair of slits defining a foam column so that the foam core has a plurality of longitudinally spaced apart and transversely extending foam columns, each foam column having a pair of generally vertical column side walls defining the slits, the foam core being formed to include a plurality of slots, each slot being associated with a slit and extending generally vertically upwardly from the bottom surface to the lower end of its associated slit so that the slot cooperates with the slit to define an opening extending through the foam core from the top surface to the bottom surface, each slot extending transversely from a first slot end spaced apart from the first side of the core and a second slot end spaced apart from the second side of the core. 
     
     
       13. The mattress core of  claim 12 , wherein the distance between the first and second slit ends is greater than the distance between the first and second slot ends. 
     
     
       14. The mattress core of  claim 12 , wherein the first slot end is spaced apart from the first slit end and the second slot end is spaced apart from the second slit end. 
     
     
       15. The mattress core of  claim 12 , wherein a plurality of slots are associated with each slit. 
     
     
       16. The mattress core of  claim 10 , wherein the plurality of slots associated with each slit includes three slots. 
     
     
       17. The mattress core of  claim 12 , further comprising a low friction material received by one slit, the low friction material being formed to include a tab received by the slot so that the low friction material extends from the top surface of the foam core to the bottom surface of the foam core. 
     
     
       18. An elongated mattress core for a mattress structure, the mattress core comprising a foam core including an upwardly-facing top surface, a bottom surface spaced apart from the top surface, and first and second elongated sides connecting the top and bottom surfaces, the foam core being formed to include a plurality of longitudinally spaced apart transverse slits extending downwardly from the top surface, each slit terminating at a lower end spaced apart from the bottom surface by a first distance and extending transversely from a first slit end spaced apart from the first side of the foam core to a second slit end spaced apart from the second side of the foam core, each adjacent pair of slits defining a foam column so that the foam core has a plurality of longitudinally spaced apart and transversely extending foam columns, each foam column having a pair of generally vertical column side walls defining the slits, the foam core including longitudinally spaced apart head, shoulder, seat, thigh, and foot zones, each zone including at least one foam column, the foam columns of each zone being made from foam having a selected indention load deflection, the indention load deflection of the foam in each zone being selectable for each for each zone independently of the other zones, each of the foam columns being formed to include a second shallow slit extending downwardly from the top surface and terminating at a lower end of the shallow slit that is spaced apart from the bottom surface by a second distance and extending transversely from a first shallow slit end spaced apart from the first side of the core to a second shallow slit end spaced apart from the second side of the core, the second distance of each shallow slit within each zone being generally equal to the second distance of each other shallow slit within the zone, the second distance in one of the head, shoulder, seat, thigh, and feet zones being different from the second distance in another of the head, shoulder, seat, thigh, and feet zones. 
     
     
       19. An elongated mattress core for a mattress structure, the mattress core comprising a foam core including an upwardly-facing top surface, a bottom surface spaced apart from the top surface, and first and second elongated sides connecting the top and bottom surfaces, the foam core being formed to include a plurality of longitudinally spaced apart transverse slits extending downwardly from the top surface, each slit terminating at a lower end spaced apart from the bottom surface by a first distance and extending transversely from a first slit end spaced apart from the first side of the foam core to a second slit end spaced apart from the second side of the foam core, each adjacent pair of slits defining a foam column so that the foam core has a plurality of longitudinally spaced apart and transversely extending foam columns, each foam column having a pair of generally vertical column side walls defining the slits, the foam core including a frame including an elongated first foam side member having an inner side surface and an outer side surface spaced apart from the inner side surface and defining the first side of the foam core and an elongated second foam side member having an inner side surface and an outer side surface spaced apart from the inner side surface and defining the second side of the foam core, the slits extending transversely from the inner side surface of the first foam side member to the inner side surface of the second foam side member, each side member including an upper foam side member attached to at least one foam column of the plurality of foam columns and a lower foam side member positioned beneath the upper foam side member and attached to at least one foam column of the plurality of foam columns. 
     
     
       20. A mattress structure comprising 
       a base including a perimetral rectangular base frame having a top surface and defining a central opening therein, and a foam bottom attached to the base frame and having a top surface spaced apart from and beneath a plane defined by the top surface of the frame to define a core-receiving space, and  
       a foam core including a rectangular core frame having a bottom surface and defining a central opening therein and a plurality of transversely extending foam columns having bottoms and received in the central opening the foam core, the form core being carried by the base so that the bottom surface of the core frame engages the top surface of the base frame and the bottoms of the foam columns are received in the core-receiving space.  
     
     
       21. The mattress structure of  claim 20 , wherein the bottoms of the foam columns engage the top surface of the bottom of the base. 
     
     
       22. The mattress structure of  claim 20 , wherein the foam core is of unitary construction. 
     
     
       23. The mattress structure of  claim 20 , wherein each foam column includes two generally vertically extending side walls extending transversely between longitudinal sides of the core frame, the side walls having a shear coating having a low coefficient of friction to minimize the frictional engagement between adjacent foam columns so that each foam column can compress and decompress independently of the compression or decompression of each adjacent foam column. 
     
     
       24. The mattress structure of  claim 23 , wherein the shear coating includes a fabric material having a low coefficient of friction. 
     
     
       25. The mattress structure of  claim 20 , further comprising a mattress cover having a top and an interior region receiving the base, the foam core, and a shear layer made from a material having a low coefficient of friction and positioned to lie between the foam core and the top of the mattress cover so that the mattress cover can slide relative to the foam core. 
     
     
       26. The mattress structure of  claim 25 , wherein the mattress cover includes a top cover covering the foam core and a bottom cover covering the base and connected to the top cover by a zipper positioned along the perimeter of the base frame. 
     
     
       27. The mattress structure of  claim 26 , further comprising a storage cover cooperating with the top cover to define a storage space receiving the foam core, the storage cover connected to the top cover by a zipper positioned along the perimeter of the core frame. 
     
     
       28. A mattress structure comprising 
       an elongated foam core of unitary construction including a top surface, a bottom surface, and a plurality of longitudinally spaced-apart and transversely-extending foam columns, each foam column having first and second longitudinally spaced-apart side walls, each pair of adjacent side walls of adjacent foam columns defining a slit so that the foam core includes a plurality of longitudinally spaced-apart slits, each pair of adjacent side walls further defining a slot beneath the slit and extending downwardly therefrom to the bottom surface, each slot and its respective slit cooperating to define an opening extending from the top surface to the bottom surface, and  
       a shear panel including a first tab, a first side panel attached to the first tab, a top panel attached to the first side panel, a second side panel attached to the top panel, and a second tab attached to the second side panel, the shear panel being made from a material having a low coefficient of friction and being wrapped around one foam column of the plurality of foam columns so that the top panel engages the top surface, the first and second side panels engage the first and second side walls, the first tab is received by the slot defined by the first side wall and extends therethrough, and the second tab is received by the slot defined by the second side wall and extends therethrough.  
     
     
       29. The mattress structure of  claim 28 , wherein the first tab is attached to the second tab to hold the shear panel onto the foam column. 
     
     
       30. The mattress structure of  claim 29 , wherein an I-shaped connector penetrates both of the first and second tabs to attach the first tab to the second tab. 
     
     
       31. The mattress structure of  claim 28 , wherein the shear panel is a unitary elongated panel including a plurality of tabs, a plurality of side panels, and a plurality of top panels, each slot receiving a portion of the material having a low coefficient of friction so that each foam column is compressible and decompressible independently of each other foam column. 
     
     
       32. The mattress structure of  claim 28 , wherein three transversely spaced apart first tabs are attached to the first side panel of the shear panel and three transversely spaced apart second tabs are attached to the second side panel of the shear panel. 
     
     
       33. The mattress structure of  claim 28 , further comprising a mattress cover having a top, the mattress cover defining an interior region receiving the foam core and shear panel, and a shear layer made from a material having a low coefficient of friction positioned to lie between the top of the mattress cover and the shear panel so that the mattress cover can slide relative to the foam core. 
     
     
       34. The mattress structure of  claim 28 , wherein each foam column includes a top portion and a bottom portion beneath the top portion, the side walls of each foam column adjacent to the top portion define each respective slit, the side walls of each foam column adjacent to the bottom portion define each respective slot, and the bottom portion of each foam column is attached to the bottom portion of each adjacent foam column so that the foam core is unitary construction. 
     
     
       35. A mattress structure comprising: 
       a mattress core,  
       a mattress cover having a top and a bottom and defining an interior region receiving the mattress core, the top and bottom of the mattress cover being separate pieces that couple together to define the interior region, and  
       a shear layer made from a material  fabric having a low coefficient of friction, the shear layer being positioned to lie between the mattress core and the top mattress cover so that the mattress cover can slide relative to the mattress core.  
     
     
       36. The mattress structure of  claim 35 , wherein the mattress core includes a rectangular foam frame defining a central opening therein and a plurality of foam columns received therein, and the shear layer encases the mattress core. 
     
     
       37. A mattress structure comprising: 
       a mattress core,  
       a mattress cover having a top and a bottom and defining an interior region receiving the mattress core, and  
       a shear layer made from a material having a low coefficient of friction, the shear layer being positioned to lie between the mattress core and the top of the mattress cover so that the mattress cover can slide relative to the mattress core, the mattress core having a top surface, a bottom surface vertically spaced apart from the top surface, and generally vertical sides connecting the perimeter of the top surface to the bottom surface, and the shear layer being a unitary member having a top panel engaging and covering the top surface of the foam core, downwardly extending sides appended to the top panel and engaging and covering the sides of the foam core, and a fitted portion engaging the bottom surface of the foam core.  
     
     
       38. A mattress structure consisting essentially of a cover having an interior region, and a plurality of foam columns located within the interior region of the cover, each foam column having opposite sidewalls configured to abut a sidewall of an adjacent column, each sidewall having a shear covering surface which has a low coefficient of friction to reduce frictional forces resulting from engagement of adjacent column sidewalls during compression and decompression of the columns. 
     
     
       39. A mattress structure consisting essentially of a cover having an interior region, and a plurality of foam columns located within the interior region of the cover, each foam column having opposite sidewalls configured to abut a sidewall of an adjacent column, each sidewall having a shear covering surface which has a low coefficient of friction to reduce frictional forces resulting from engagement of adjacent column sidewalls during compression and decompression of the columns, and a shear layer located between the plurality of columns and the cover. 
     
     
       40. A mattress structure comprising: 
       
         a mattress core,  
       
       
         a mattress cover having a top and a bottom and defining an interior region receiving the mattress core, the top and bottom of the mattress cover being separate pieces that couple together to define the interior region, and  
       
       
         a shear layer made from a textile material having a low coefficient of friction, the shear layer being positioned to lie between the mattress core and the top mattress cover so that the mattress cover can slide relative to the mattress core. 
       
     
     
       41. The mattress structure of  claim 40 , wherein the mattress core includes a rectangular foam frame defining a central opening therein and a plurality of foam columns received therein, and the shear layer encases the mattress core.