shown in fig7 is an absorbent device 10 according to the invention placed on the mattress of a bed 12 to protect the bedding from damage due to for example urine . referring principally to fig2 and fig3 the absorbent device 10 includes a bag like member 14 subdivided into an upper compartment 16 and a lower compartment 18 . the upper compartment 16 is formed by a nonabsorbent , moisture permeable , open weave fabric such as a polyester cloth within which is encased a non - absorbent , open celled , moisture permeable , resilient , supportive upper cushion 28 . sealed to the top peripherial edge 26 of the upper portion of the bag like container is a bag like element made of moisture impervious material such as vinyl having depending peripherial side walls 30 and a bottom wall 32 . it can be seen that the lower side covering of the casing which contains the upper cushion 28 forms an internal horizontal wall 24 that subdivides the bag like member 14 into the two ( upper and lower ) compartments 16 and 18 . the peripherial side walls 30 and upper compartment casing walls 22 , 24 are all attached together at the peripherial edge 26 to form a water tight connection such as by sewing , a heat seal or adhesive bonding . a self contained filter cushion member 36 is removably housed within the lower compartment 18 . as shown in fig1 and 7 , the peripherial wall 30 is provided with a zippered access 32 through which the filter cushion member 36 can be removed from or inserted into compartment 18 . the access 32 can be provided either on the end of the device as shown or along a long side of the device if desired to provide access from the side of the bed . as shown in fig3 the filter cushion member 36 occupies substantially the entire volume of the lower compartment 18 and comprises a non - absorbent , moisture permeable , resilient , at least semi - supportive filter cushion element 38 similar to the upper cushion 28 which is encased within a non - absorbent , moisture permeable open weave fabric casing 48 such as a polyester cloth . as shown best in fig5 and 6 , the filter cushion element 38 includes two halves or , as shown in fig5 is of a clam shell type construction wherein the inner surfaces of each half are provided with a plurality of aligned pairs of generally semi - circular , transverse relieved portions such as 40 , 42 . positioned within each pair of relieved portions are elongated hard rubber , tubular or cylindrical , longitudinally flexible , but radially non - compressive , support members 44 . positioned between adjacent support members is an absorbent element such as a cotton liner or pads 46 . the clam shell or opposing halves of the filter cushion element 38 are closed and glued together against the absorbent element 46 and support tubes 44 , as shown in fig6 and the assembly is subsequently encased in the non - absorbent , moisture permeable covering 48 . as shown in fig3 and 7 , one end of the filter cushion member 36 is provided with a handle 50 to facilitate insertion and removal of the filter cushion member into and from the compartment 18 . if the access 32 is along one long side 30 of the bag like member , the handle would be appropriately placed on a corresponding long side of the filter cushion member . it should be noted that , in use , as shown in fig4 the support rods 44 provide support to the user because , although the support members 44 can flex along their longitudinal axis , because they are noncompressible radially , they limit compression of the filter cushion element 38 to substantially no more than the diameter of the support members 44 and , accordingly , they support the weight of the user &# 39 ; s body , as represented by the arrows 45 , and , advantageously , the absorbent cotton liner 46 is able to retain moisture since it remains substantially uncompressed under the weight of the user &# 39 ; s body . further , while the thickness of the filter cushion element 38 is on the order of about 3 - 4 inches , the upper cushion 28 is substantially thinner and on the order of about 1 / 2 &# 34 ; thick . the compressibility , and in particular the relative thinness of the upper cushion 28 , as well as the compression limiting effect of the support members 44 , is important to proper functioning of the device . referring to fig4 when a user lies on the absorbent device and a liquid or moisture , such as urine , is present , the liquid or moisture passes through the porous outer top covering 22 into the porous upper cushion 28 . although the cushion 28 is non - absorbent and open celled and the vast majority of the moisture passes through the cushion , some moisture is inherently retained within the open cell structure due simply to the size of the cushion . accordingly , the upper cushion 28 is made relatively thin , but still supportive , whereby the weight of the user , represented by the arrows 45 , although still supported , will compress the majority of the thickness of the cushion 28 and force the moisture and liquid out of the upper cushion through lower porous wall 24 into and through the porous casing 48 into the lower filter cushion element 38 of the filter cushion member 36 . eventually , the moisture or liquid passes through the non - absorbent , permeable filter cushion element 38 and enters and is absorbed and retained by the cotton absorbent element 46 . as noted , the relatively thin upper cushion 28 is essentially &# 34 ; pumped &# 34 ; by the weight of the user &# 39 ; s body to move moisture down into the filter cushion member below for collection and retention . as noted above , the support members prevent the weight of the user &# 39 ; s body from compressing the absorbent element 46 and the captured moisture can not be &# 34 ; squeezed &# 34 ; from the absorbent element , but rather remains retained in the element 46 . any moisture that may escape from the absorbent 46 , such as when the element becomes saturated with use between cleaning or which naturally escapes by gravity , will be retained within the compartment 18 by the waterproof moisture impervious covering 30 , 32 . advantageously , the upper cushion 28 , and in particular the top covering 22 that is in contact with the user &# 39 ; s body , remains substantially dry . periodically , the filter cushion member 36 is removed and is easily cleaned by &# 34 ; hosing down &# 34 ; to flush the absorbed liquid from the absorbent element 46 and drying the entire filter cushion member by simple air drying . having described the preferrd embodiment of the invention , those skilled in the art having the benefit of that description an the accompanying drawings can readily devise other embodiments and modifications and such other embodiments and modifications are to be considered to be within the scope of the appended claims .
an absorption pad for a bed is disclosed including a bag like member having an upper and a lower compartment , a moisture impervious periphery and bottom and a moisture permeable top covering and internal divider wall . a non - absorbant , moisture permeable cushion is encased in the upper compartment and a removable filter member including a non - absorbant moisture permeable filter cushion member having an internal moisture absorbing element and support members is disposed in the lower compartment .