Patent ID: 12239589

DETAILED DESCRIPTION

FIG.1illustrates a patient support apparatus30including a mattress cover32in accordance with an exemplary embodiment of the present disclosure. The mattress cover32is adapted to be coupled to a mattress34providing movement therapy to be described with a patient P supported thereon. The patient support apparatus30shown inFIG.1is a hospital bed, but alternatively may be a stretcher, cot, trolley, gurney, wheelchair, recliner, chair, table, or suitable support or transport apparatus.

The patient support apparatus30may include a base36adapted to rest upon a floor surface, and a patient support deck38coupled to the base36. In certain embodiments, an intermediate frame40is spaced above the base36with the patient support deck38coupled to or disposed on the intermediate frame40. A lift device42may be operably coupled to the intermediate frame40and the base36for moving a patient support portion44to be described relative to the base36. In the exemplary embodiment illustrated inFIG.1, the lift device42includes a pair of linear actuators46, but other suitable constructions are contemplated.

In certain embodiments, the patient support deck38includes articulating sections48configured to articulate the patient support portion44between various configurations. The articulating sections48may include a fowler, a seat section, a thigh section, a leg section, and the like, movably coupled to actuators50. For example, the fowler may be moved between a first position in which the patient P is supine, as illustrated inFIG.1, and a second position in which the torso of the patient P is positioned at an incline. For another example, a gatch maneuver may be performed in which the position(s) of the thigh and leg sections are adjusted. In the aforementioned examples, the shape of the mattress34(and/or the mattress cover32) may be altered, and it is understood that the advantageous features of the mattress cover32to be described in the context of lateral rotation therapy may be applied to therapies involving movement of the articulating sections48. It is also understood that in other examples, the patient support deck38may be rigid and unable to articulate.

The patient support apparatus30includes the mattress34coupled to or supported on the patient support deck38.FIG.2shows the mattress34(in phantom) including an upper surface52and a lower surface54opposite the upper surface52. The thickness T of the mattress34may be defined between the upper surface52and the lower surface54. The mattress34includes sides56that may extend between the upper and lower surfaces52,54. In manners to be further described throughout the present disclosure, in certain embodiments providing the movement therapy includes increasing the thickness T of the mattress34with the patient P disposed thereon.

Referring now toFIG.3, the upper surface52of the mattress34may be associated with an upper layer58. In other words, the upper layer58defines the upper surface52of the mattress34with the mattress cover32in contact with the upper layer58. The upper layer58may be formed primarily from polyurethane, but other suitable materials are contemplated. In another example, the upper layer58is formed of foam, another material, or a combination thereof.

The mattress34includes a patient turning device60. The patient turning device60may be defined as a layer within the mattress34disposed intermediate the upper surface52and the lower surface54, as shown inFIG.3, or external the mattress34in an embodiment to be described (seeFIG.14). The patient turning device60may include one or more inflatable bladders62adapted to receive fluid from a fluid source to expand during the movement therapy (also referred to herein as a patient turning operation). The fluid from the fluid source may be a liquid, such as water, or a gas, such as air. Alternatively, it is contemplated that mechanical and/or electromechanical means may be provided in order to effectuate the movement of the mattress34. For example, actuators (e.g., rotary actuators, linear actuators, springs, coils, and the like) may be operated by a controller to provide the movement therapy. For another example, components comprised of shape memory material(s) (e.g., Nitinol) may be coupled to the mattress34in a suitable manner. The shape memory material provides for a change in shape in response to application or removal of forced applied to the components with the change in shape resulting in corresponding movement of the mattress34to provide the movement therapy.

An inner membrane layer64may be provided within the mattress34. In one example, the inner membrane layer64is in fluid communication with a source of air (not shown) circulated through the inner membrane layer64to control humidity of the mattress cover32. In the exemplary embodiment ofFIG.3, the inner membrane layer64is in direct contact with the patient turning device60. The mattress34further includes a mattress core layer66that may be disposed in direct contact with the inner membrane layer64. The mattress core layer66may be formed of foam, another material, or a combination thereof. In one example, the structure of the mattress core layer66takes the form of honeycombs that are adapted to resiliently buckle when supporting the patient P on the upper layer58of the mattress34.

In certain embodiments, the mattress34(or the mattress cover32) include a fire barrier layer (not shown). The fire barrier layer may be positioned intermediate the patient turning device60and the inner membrane layer64. One exemplary fire barrier layer suitable for the present application is provided under the tradename Nomex (DuPont Company, Wilmington, Dela.). A self-healing layer (not shown) may be provided and positioned, for example, in direct contact with the upper layer58or intermediate the upper layer58and the patient turning device60. The self-healing layer may be formed from a low-durometer poured urethane with the capability of self-sealing in the event of small, inadvertent punctures from sharps (e.g., a hypodermic needle). It is to be understood that the arrangement of the specific layers of the mattress34is not specifically limited to those set forth above. Further, in certain embodiments the mattress34may include more or fewer layers. For example, the mattress34may not include the upper layer58with the mattress cover32in contact with one of the patient turning device60, the inner membrane layer64, the mattress core layer66, and the like.

The mattress cover32is coupled to the mattress34. The mattress cover32defines the patient support portion44adapted to cover the upper surface52of the mattress34. Thus, absent bedding and the like, the patient P is supported by and in contact with the patient support portion44of the mattress cover32. In certain embodiments, the mattress cover32may be coupled to the mattress34so as to substantially encase the mattress34. Referring toFIG.2, the patient support portion44covers the upper surface52of the mattress34. The mattress cover32may include a bottom portion68coupled to the patient support portion44with the bottom portion68covering the lower surface54of the mattress34. In other words, the patient support portion44and the bottom portion68may be positioned opposite the mattress34. The mattress cover32may include peripheral portions70extending between the patient support portion44and the bottom portion68. The peripheral portions70may be positioned adjacent to and/or adapted to cover the sides56of the mattress34as shown inFIG.2. With the patient support portion44, the bottom portion68, and the peripheral portions70covering the respective surfaces of the mattress34, the mattress cover32substantially encases the mattress34. In other exemplary embodiments to be described, the mattress cover32covers the upper surface52of the mattress34(and in some instances the peripheral portions70), but otherwise does not substantially encase the same.

In certain embodiments, the mattress cover32includes a fastening device72coupling two portions of the mattress cover32such that the mattress cover32is removably coupled to the mattress34.FIG.2shows the fastening device72including a zipper extending about at least a portion of the peripheral portions70of the mattress cover32. Other fastening devices may include snaps, clips, tethers, hook and eye connections, adhesive, and the like. In other exemplary embodiments, the patient support portion44, the bottom portion68, and/or the peripheral portions70may be integrally formed such that the mattress cover32is of unitary structure and not removable from the mattress34.

The patient support portion44includes an outer periphery74sized so that a majority of the patient P is supported on the patient support portion44, particularly during the movement therapy. In one example, the outer periphery74is defined by the edges between the patient support portion44and the peripheral portions70of the mattress cover32. In another example, the outer periphery74is defined by boundaries of a predetermined area of the patient support portion44with the area adapted to support the patient P during the movement therapy. It is shown inFIGS.1,2and4Athat the mattress cover32and the mattress34have a length and width sufficient to accommodate the patient P on the patient support portion44. In other words, the outer periphery74that may define the length and width of the patient support portion44with the majority of the patient P positioned within the outer periphery74.

Referring now toFIGS.4A and4B, an exemplary operation of the movement therapy will now be described.FIG.4Ashows the patient support apparatus30in the absence of movement therapy. The thickness T of the mattress34defined between the upper and lower surfaces52,54is substantially constant across the width of the mattress34. The resulting may be that the upper surface52and the patient support portion44of the mattress cover32being substantially horizontal with the patient P situated thereon in the supine position as shown. The patient turning device60is actuated to alter the thickness T of the mattress34. One or more of the inflatable bladders62of the patient turning device60are selectively inflated with fluid from the fluid source (not shown). Expansion of the inflatable bladder(s)62increase the thickness T of the mattress34and the mattress cover32covering at least a portion of the mattress34.FIG.4Bshows several of the inflatable bladders62expanded with the thickness T′ of the mattress34being increased to define the movement therapy. The increased thickness T′ of the mattress34turns the patient P in a corresponding manner. For example,FIG.4Bshows the patient P is turned counterclockwise with the increased thickness T′ of the right side of the mattress34. Conversely, the inflatable bladder(s)62may be selectively deflated, such as by an actuated valve and/or under the influence of a vacuum to decrease the thickness of the mattress34and the mattress cover32. Once the increased thickness T′ is decreased to the thickness T of the mattress34, the mattress cover32and the mattress34may be considered in the absence of movement therapy.

The mattress cover32must expand or otherwise provide slack to prevent the mattress cover32from impeding increasing the thickness T of the mattress34(e.g., expanding of the inflatable bladders62). The mattress cover32includes an augmenting feature76associated with one of the peripheral portions70. The augmenting feature76is adapted to move between a stored configuration in the absence of the movement therapy, and a deployed configuration in response to increasing the thickness T of the mattress34during the movement therapy. It is to be understood that the augmenting feature76may include more than one augmenting feature associated with more than one of the peripheral portions70. In one example including the mattress34having a conventional shape, each of four of the peripheral portions70may be associated with the augmenting feature76. The augmenting feature76is represented schematically inFIGS.1,4A,4B and11with specific embodiments to be described.

FIGS.5-7and9are sectional views of the mattress cover32and mattress34in accordance with several exemplary embodiments of the present disclosure (with internal structure(s) of the mattress34omitted for clarity). Referring toFIG.5, the peripheral portion70includes a width W defined between the patient support portion44and the bottom portion68of the mattress cover32. In one example, the width W of the peripheral portion70may be considered the thickness T of the mattress cover32. As mentioned, the augmenting feature76is associated with the peripheral portion70. The width W of the peripheral portion70is adapted to increase as the augmenting feature76moves from the stored configuration to the deployed configuration in response to increasing the thickness T of the mattress34during the movement therapy. In other words, the augmenting feature76may provide the slack to permit the mattress cover32to expand during the movement therapy. Likewise, the width W of the peripheral portion70is adapted to decrease as the augmenting feature76moves from the deployed configuration towards the stored configuration in response to decreasing the thickness T of the mattress34during the movement therapy. The augmenting feature76returns to the stored configuration in the absence of the movement therapy.

In the exemplary embodiment ofFIGS.5-7the augmenting feature76includes accordion-like, bellows-like, or concertinaed material78coupled to the peripheral portion70. The concertinaed material78is adapted to assume an expanded state when the augmenting feature76is in the deployed configuration, and a natural state when the augmenting feature76is in the stored configuration. During the movement therapy the thickness T of the mattress34increases (i.e., the upper surface52moves upwardly in the elevational view ofFIG.5), thereby providing a corresponding upward force to the patient support portion44of the mattress cover32(the mattress34is supported below by the patient support deck38). The patient support portion44moves away from the bottom portion68. The peripheral portion70, which would otherwise be placed in tension and potentially impede further increase in the thickness T of the mattress34, is provided slack by the concertinaed material78such that the width W of the peripheral portion70increases in a corresponding manner. Conversely, as the patient support portion44moves towards the bottom portion68, such as during cycling of the movement therapy, the concertinaed material78returns to the natural state and provides for compact design of the augmenting feature76and the peripheral portion70of the mattress cover32.

In one example, the concertinaed material78is fabricated from thermoformed plastic formed in the concertinaed manner illustrated inFIG.5in an unstressed, unflexed, or natural state. The thermoformed plastic includes some flexibility and resiliency. The thermoformed plastic is adapted to flex at the folds of the concertinaed material78such that the concertinaed material78generally straightens (i.e., moves to the expanded state) as the augmenting feature76moves from the stored configuration to the deployed configuration. As the augmenting feature76moves from the deployed configuration to the stored configuration, the resiliency of the thermoformed plastic causes the concertinaed material78to return from the expanded state to the natural state. In other words, in the exemplary embodiments including the concertinaed material78, the concertinaed material78is in the natural state when the augmenting feature76is in the stored configuration, and the concertinaed material78is in the expanded state when the augmenting feature76is in the deployed configuration.

In the exemplary embodiment illustrated inFIG.5, the concertinaed material78is positioned adjacent most of the width W of the peripheral portion70. In exemplary embodiments of the augmenting feature76with the concertinaed material78shown inFIGS.6and7, the concertinaed material78is positioned near the patient support portion44. As mentioned, the concertinaed material78may be thermoformed plastic, for example, with pleats formed from radiofrequency welding. The augmenting feature76ofFIG.5moves to the deployed configuration (shown in phantom) with substantially an entirety of the concertinaed material78remaining external to the outer periphery74of the patient support portion44. In other words, in the expanded state the concertinaed material78may extend substantially vertically and/or parallel with the sides of the mattress34.

With the exemplary embodiments ofFIGS.6and7showing the augmenting feature76positioned near the patient support portion44, a portion of the concertinaed material78moves inwardly (e.g., within the outer periphery74) as the augmenting feature76moves from the stored configuration to the deployed configuration (shown in phantom). InFIG.6, the concertinaed material78includes pleats that move between the natural state and the expanded state in the accordion-like or the bellows-like manner. InFIG.7, the concertinaed material78includes a hub point80and spokes82of the material connected to the patient support portion44at the hub point80. The spokes82articulate about the hub80as the concertinaed material78moves between the natural state and the expanded state. Outer legs84extend between the spokes82to provide aesthetics such that the mattress cover32appears “smooth” with the augmenting feature76in both the stored and deployed configurations. It is to be understood that features from the exemplary embodiments of the augmenting feature76shown inFIGS.5-7may be used in combination to provide for greater expansion of the mattress cover32during the movement therapy.

FIGS.8and9show the augmenting feature76in accordance with another exemplary embodiment of the present disclosure. The augmenting feature76includes a fold of material88coupled to the peripheral portion70. The fold of material88is adapted to be positioned adjacent the peripheral portion70when the augmenting feature76is in the stored configuration, as shown inFIGS.8and9. The fold of material is also adapted to extend away from the peripheral portion70when the augmenting feature76is in the deployed configuration, as shown inFIG.10.

Referring toFIG.9, the fold of material88includes a coupled end90coupled to the peripheral portion70near or proximate to the patient support portion44. In another example, the coupled end90may be coupled to the patient support portion44near or proximate to the peripheral portion70. The coupled end90may be considered an articulating or pivot point about which the fold of material88articulates or pivots as the augmenting feature76moves between the stored and deployed configurations. The fold of material88includes a free end92opposite the coupled end90. The free end92is movable relative to the coupled end90as the augmenting feature76moves between the stored and deployed configurations. For example, the free end92may be adapted to be positioned adjacent the peripheral portion70with the augmenting feature76in the stored configuration, as shown inFIGS.8and9, and away from the peripheral portion70with the augmenting feature76in the deployed configuration.

For both function and aesthetics it is generally desirable to maintain the fold of material88adjacent the peripheral portion70with the augmenting feature76in the stored configuration. The present disclosure contemplates doing so in several manners. In one exemplary embodiment, the augmenting feature76includes a coupler94coupled to either the peripheral portion70or the fold of material88, and a counterposing coupler96coupled to the other. The couplers94,96may include snaps, clips, hook and eye connections, adhesive, and the like. In one example shown inFIG.9, the coupler94is a magnet coupled to the fold of material88, and the counterposing coupler96is ferromagnetic material coupled to the peripheral portion70. Based on well-known principles of magnetism, when the magnet and the ferromagnetic material automatically couple when positioned sufficiently proximate to one another. Thus, the magnet and the ferromagnetic material are adapted to automatically couple with the augmenting feature76in the stored configuration, and automatically decouple as the augmenting feature76is moved from the stored configuration the deployed configuration. For example, a magnet having low-tension, high-shear magnetic properties may be particularly suitable for the application. During the movement therapy the thickness T of the mattress34increases (i.e., the upper surface52moves upwardly in the elevational view ofFIG.9), thereby providing a corresponding upward force to the patient support portion44of the mattress cover32. The fold of material88, initially constrained by the couplers94,96, is placed in tension until the forces on the fold of material88are sufficient to overcome the forces between the couplers94,96, for example, the high-shear magnetism between the magnet and the ferromagnetic material. The couplers94,96automatically decouple, after which the free end92of the fold of material88articulates about the coupled end90as the thickness T of the mattress34continues to increase. The fold of material88may slidably move upwardly along the peripheral portion70, and further move above the patient support portion44to extend away from the peripheral portion70, as shown inFIG.10. As the thickness T of the mattress34is decreased, the upper surface52of the mattress34moves downwardly. The downward movement of the upper surface52of the mattress34and the patient support portion44provides slack to the fold of material88, which descends or moves downwardly under the influence of gravity. As the augmenting feature76nears the stored configuration, the free end92may be positioned adjacent the patient support portion44such that the couplers94,96are sufficiently proximate to automatically couple, such as under the force of magnetism. The resulting arrangement includes the fold of material88of the mattress cover32being nestled for the functional and aesthetic benefit of the patient P and the caregivers moving about the patient support apparatus30.

In certain embodiments, additional couplers98,100are positioned at or near the patient support portion44. With reference toFIGS.8and9, the coupler98may be a magnet coupled to the fold of material88, and the counterposing coupler100is ferromagnetic material coupled to the peripheral portion70.FIG.9shows the coupler98positioned near the coupled end90of the fold of material88. When viewed in the perspective view ofFIG.8, the magnets extend along the length of the mattress cover32. For example, a magnet having low-tension, high-shear magnetic properties may be particularly suitable for the coupler98positioned at or near the patient support portion44to prevent detachment upon “hammocking” of the patient support portion44(i.e., alteration of the patient support portion44result in a generally concave or arcuate contour), but provide for easy detachment during the movement therapy. The couplers98,100retain the fold of material88adjacent to the peripheral portion70until the tensile forces on the couplers98,100is sufficient to decouple the couplers98,100, after which the augmenting feature76moves towards the deployed configuration in the manner previously described. It is to be understood the couplers98,100at or near the patient support portion44may be in addition to the couplers94,96at or near the free end92of the fold of material88.

The augmenting feature76of the mattress cover32may include a resilient member102coupled to the fold of material88at or near the free end92. The resilient member102is adapted to bias the fold of material88towards the stored configuration. In other words, the resilient member102is adapted to bias or urge the free end92of the fold of material88to the position adjacent the peripheral portion70. With continued reference toFIGS.8and9, the resilient member102may be coupled to the fold of material88at or near the free end92and to another one of the peripheral portions70′ of the mattress cover32. As the augmenting feature76is moved from the stored configuration to the deployed configuration, the resilient member102is tensioned. For example, with the resilient member102coupled to the peripheral portion70′ as shown inFIG.8, the resilient member102is elastically tensioned by a force in a direction generally transverse to a direction of the resilient member102(e.g. the transverse force is upwardly with the resilient member102oriented substantially horizontally). The resilient member102continues to urge or bias the fold of material88towards the stored configuration against the forced associated with increasing the thickness T of the mattress34during the movement therapy. It is understood that the forces associated with increasing the thickness T of the mattress34during the movement therapy are sufficient to overcome the biasing forces provided by the resilient member102.

In another exemplary embodiment, the resilient member102is coupled to the fold of material88at or near the free end92and to the peripheral portion70of the mattress cover32(to which the fold of material88is coupled at the coupled end90). In many respects similar to the aforementioned exemplary embodiment, the resilient member102is adapted to bias the fold of material88towards the stored configuration, or to the position adjacent the peripheral portion70. The resilient member102is elastically tensioned by a force, in this example a force in a direction generally axial to a direction of the resilient member102.

In certain embodiments, the resilient member102may be an elastic band. The elastic band may be coupled at one end to the fold of material88, and at the other end to one of the peripheral portions70,70′. The elastic band is elastically tensioned by the forces, axial or transverse, associated with the augmenting feature76moving from the stored configuration the deployed configuration in response to increasing the thickness T of the mattress34during the movement therapy. As is understood with elasticity generally, the elastic band is biased to return an untensioned state, which includes the fold of material88positioned adjacent the peripheral portion70. In another exemplary embodiment, the resilient member102may be an elongate rod104. Referring toFIG.10, the elongate rod104may be coupled at its ends to the peripheral portion70or any suitable structure of the mattress cover32. The elongate rod104is coupled to the fold of material88in a manner that permits the augmenting feature76to move from the stored configuration the deployed configuration against the biasing force provided by the elongate rod104. For example, the elongate rod104may be arcuate in an untensioned state with a central portion of the elongate rod104coupled to the fold of material88, such as extending through a loop of fabric in the fold of material88. In manners previously described, as the augmenting feature76is moved from the stored configuration to the deployed configuration, the resilient elongate rod104is tensioned (e.g., bent) by a force in a direction generally transverse to a direction of the elongate rod104. The elongate rod104continues to bias the fold of material88towards the stored configuration against the constraint provided by increasing the thickness T of the mattress34during the movement therapy. In some respects, the elongate rod104may be considered to function as an inverted leaf spring. In one non-limiting example, the elongate rod104may be formed primarily of resilient carbon having the desired flexural properties to achieve the aforementioned function as the augmenting feature76moves between the stored and deployed configurations. Other suitable materials forming the elongate rod104are contemplated, such as metal, polymer, rubber, and the like.

With continued reference toFIGS.7-10, the mattress cover32may include a securing member108for preventing relative movement between the mattress cover32and the mattress34. With the mattress cover32substantially encasing the mattress34, relative movement between the two may be limited; however, it may be advantageous to ensure any relative movement is localized to the augmenting feature76, which is specifically adapted to move between the stored and deployed configurations. Further, in another exemplary embodiment to be described in which the mattress cover32does not substantially encase the mattress34, it may be particularly advantageous to provide the securing member108. In certain embodiments, the securing member108may extend along one or more of the peripheral portions70of the mattress cover32. The securing member108may be disposed between the fold of material88and the peripheral portion70such that the fold of material88is permitted to move relative to the mattress34, but the peripheral portion70is restricted from doing so. In one example, the securing member108is positioned between the fold of material88and the peripheral portion70at, near, or proximate to the coupled end90of the fold of material88, as shown inFIG.9. In many respects, positioning the securing member108at or near the coupled end90of the fold of material88ensures the free end92articulates or pivots about the coupled end90as opposed to some other aspect of the fold of material88. Suitable materials for the securing member108may include an elastic or inelastic cord, band, or wire, among others.

As mentioned above, the mattress cover32may not substantially encase the mattress34. In other words, the mattress cover32may lack one or more of the bottom portion68and/or the peripheral portions70covering the respective surfaces of the mattress34. One exemplary embodiment of the mattress cover32not substantially encasing the mattress34is shown inFIG.11. The patient support portion44includes the outer periphery74sized so that the majority of the patient P is supported on the patient support portion44during the movement therapy. In the present embodiment, the peripheral portions70are coupled to and extend from patient support portion44with the peripheral portions70positioned adjacent to and/or adapted to cover the sides56of the mattress34. The mattress cover32does not include the bottom portion68(seeFIG.2). Rather, the peripheral portions70include a lower edge110with the width W of the peripheral portion70defined between the patient support portion44and the lower edge110. The lower edge110may extend along the peripheral portion70between the patient support portion44and the lower surface54of the mattress34such that the width W of the peripheral portion70is less than the thickness T of the mattress34. As a result, a portion of the sides56of the mattress34may be exposed when the mattress cover32is coupled to the mattress34. In another example, the lower edge110extends along the bottom surface54of the mattress34. The peripheral portions70of the mattress cover32may cover the sides56of the mattress34, but a portion of the bottom surface54of the mattress34may be exposed. The augmenting feature76associated with the peripheral portion70is represented schematically and may include any one or more aspects of the exemplary embodiments of the augmenting feature76described throughout the present disclosure.

The mattress cover32removed from the mattress34by slidably moving the lower edge110along the sides56of the mattress34(i.e., the mattress cover32of the present embodiment may not include the fastening device72(seeFIG.2)). To secure the mattress cover32to the mattress34during use, the mattress cover32includes one or more retaining features112. In the exemplary embodiment illustrated inFIG.11, the retaining features112include portions of expandable fabric in many respects akin to a fitted sheet of bedding. Other fastening devices may include snaps, clips, hook and eye connections, adhesive, and the like. As mentioned, providing the securing member108may be particularly suitable for the present embodiment such that, as the thickness T of the mattress34increases during the movement therapy, relative movement of the mattress cover32is prevented other than the augmenting feature76moving from the stored configuration to the deployed configuration in manners previously described. In other words, the securing member108may limit or prevent the lower edge110of the mattress cover32from slidably moving upwardly along the sides56of the mattress34as the thickness T of the mattress34increases during the movement therapy. Other means for preventing relative movement between the mattress cover32and the mattress34are within the scope of the present disclosure.

In certain embodiments, the lower edge110may be coupled to a mechanical system adapted to permit controlled movement of and provide retraction of the mattress cover32relative to the mattress34in response to increasing and decreasing of the thickness T of the mattress34, respectively, during the movement therapy. For example, a spring-loaded roller (not shown) may be provided adjacent to the peripheral portion70or within the mattress cover32(or the mattress34). The spring-loaded roller may include a torsion spring biasing the roller to furl the lower edge110of the mattress cover32about the roller. During the movement therapy, the forces associated with increasing the thickness T of the mattress34are sufficient to overcome the biasing forces provided by the torsion spring, and the mattress cover32unfurls from the roller providing slack to accommodate the upward movement of the upper surface52of the mattress34. As the upper surface52moves downwardly, the biasing forces provided by the torsion spring urge the mattress cover32to furl the lower edge110of the mattress cover32about the roller. In some respects, the spring-loaded roller may be considered another exemplary embodiment of the augmenting feature76of the present disclosure.

Referring toFIGS.12and13, the mattress cover32in accordance with another exemplary embodiment of the present disclosure is shown. The mattress cover32includes the patient support portion44covering the upper surface52of the mattress34with the patient support portion44having the outer periphery74sized so that the majority of the patient P is supported on the patient support portion44within the outer periphery74during the movement therapy. The mattress cover32includes the bottom portion68opposite the patient support portion44with the bottom portion68adapted to cover the lower surface54of the mattress34such that the mattress34is disposed between the patient support portion44and the bottom portion68. As shown inFIG.12, the patient support portion44is adapted to at least partially overlap the bottom portion68and move relative to the bottom portion68to accommodate the increasing thickness T of the mattress34during the movement therapy.

FIG.13shows the bottom portion68, includes an upper edge114. The bottom portion68is coupled to the mattress34such that the bottom portion68covers the lower surface54of the mattress34and at least a portion of the sides56of the mattress34. In the exemplary embodiment ofFIG.13, the bottom portion68covers the lower surface52, the sides56, and a portion of the upper surface52of the mattress34. Thus, it may be considered that the peripheral portions70of previously described embodiments may be integrated with the bottom portion68of the present embodiment. The bottom portion68may include retaining features (see, for example, the retaining features112ofFIG.11) adapted to secure the bottom portion68to the mattress34. The retaining features may include portions of expandable fabric in many respects akin to a fitted sheet of bedding, or may include snaps, clips, hook and eye connections, adhesive, and the like.

The patient support portion44and the bottom portion68may overlap adjacent to opposing sides56of the mattress34, as shown inFIG.12. Furthermore, the patient support portion44substantially or completely overlaps the upper edge114of the bottom portion68when the patient support portion44is placed on the upper surface52of the mattress.FIG.12shows the upper edge114in phantom with the patient support portion44completely overlapping the upper edge114. Based on the overlapping arrangement of the patient support portion44and the bottom portion68, the mattress cover32of the present embodiment substantially encases the mattress34with the mattress cover32accommodating the increase in thickness T of the mattress34in a manner to be described. Further, overlapping arrangement of the patient support portion44and the bottom portion68allows for the mattress cover32to be quickly coupled and/or decoupled from the mattress34. The patient support portion44and the bottom portion68may be coupled with one or more resilient members116. The resilient member116biases the patient support portion44towards the bottom portion68, and the bottom portion68towards the patient support portion44with several exemplary embodiments of the resilient member116to be described.

An exemplary operation of the mattress cover32of the present embodiment will now be described. The patient support portion44is coupled to the bottom portion68with the resilient members116such that the mattress cover32substantially encases the mattress34. The patient support portion44and the bottom portion68overlap adjacent to opposing sides56of the mattress34. During the movement therapy the thickness T of the mattress34increases (i.e., the upper surface52moves upwardly in the elevational view ofFIG.5), thereby providing a corresponding upward force to the patient support portion44of the mattress cover32. The patient support portion44moves away from the bottom portion68against the biasing force provided by the resilient members116. Conversely, as the thickness T of the mattress34decreases, such as during cycling of the movement therapy, the resilient member116urges the patient support portion44moves towards the bottom portion68. In many respects the overlapping arrangement of the patient support portion44moveable relative to the bottom portion68in conjunction with the resilient members116may be considered another exemplary embodiment of the augmenting feature76.

In the exemplary embodiment illustrated inFIGS.12and13, the resilient member116is an elastic band or tether coupled to each of the patient support portion44and the bottom portion68, such as with a loop on pegs or a hook through eyelets. In certain embodiments, the resilient member116is an elastic strap coupled to the patient support portion44that wraps around the bottom portion68. The elastic strap may be positioned at or near a head end118or a foot end120of the mattress cover32(seeFIG.15). In certain embodiments, the resilient member116is a semi-rigid elongate rod acting as a leaf spring biasing the patient support portion44towards the bottom portion68, and the bottom portion68towards the patient support portion44. More than one of the aforementioned exemplary embodiments of the resilient member116may be used with variation in attachment points to be considered contemplated by the present disclosure.

In exemplary embodiments of the present disclosure discussed to this point, providing the movement therapy included increasing the thickness T of the mattress34with the patient P disposed thereon. For example,FIGS.3,4A and4Bshows the patient turning device60within the mattress34with the patient turning device60including one or more inflatable bladders62adapted to receive fluid from the fluid source to increase the thickness T of the mattress34during the movement therapy. In another exemplary embodiment shown inFIG.14, a movement therapy mattress assembly includes the mattress34having the upper surface52, the lower surface54, the sides56, and the patient turning device60. The patient turning device60shown inFIG.14is positioned adjacent to the lower surface54of the mattress34. In certain embodiments, the patient turning device60includes the inflatable bladder(s)62positioned adjacent to the lower surface54of the mattress34. In other words, the patient turning device60is external to the mattress34. Alternative embodiments of the patient turning device60may include an articulable mechanism within or external to the mattress34with the articulable mechanism adapted to change the shape of the mattress34without increasing its volume.

The patient turning device60is adapted to move at least a portion of the mattress34to provide the movement therapy. The patient turning device60may be actuated by, for example, the inflatable bladder(s)62being selectively inflated with fluid from the fluid source (not shown).FIG.14shows the inflatable bladder62associated with the right side of the mattress34at least partially inflated, and another one of the inflatable bladders62associated with the left side in an uninflated state. Expansion of the inflatable bladder(s)62moves the mattress34and the mattress cover32covering at least a portion of the mattress34. The upper surface52of the mattress34is moved upwardly with the movement corresponding to the expansion of the inflatable bladder(s)62to define the movement therapy. Conversely, the inflatable bladder(s)62may be selectively deflated, such as by an actuated valve and/or under the influence of a vacuum to permit the mattress34to move downwardly under its own weight. Once the inflatable bladder(s)62of the patient turning device60has returned to being uninflated, the mattress cover32and the mattress34may be considered in the absence of movement therapy. It is understood that during the movement therapy the thickness T of the mattress34may not be substantially alerted in the present embodiment.

The patient turning device60, while external to the mattress34, may be covered by or disposed within the mattress cover32. The mattress cover32includes the patient support portion44covering the upper surface52of the mattress34, the bottom portion68coupled to the patient support portion44, and the peripheral portions70extending between the patient support portion44and the bottom portion68. The patient support portion44includes the outer periphery74sized so that the majority of the patient P is supported on the patient support portion44within the outer periphery74during the movement therapy. The peripheral portions70cover the sides56of the mattress34.

The bottom portion68(and in certain embodiments the peripheral portion70) covers the inflatable bladder(s)62of the patient turning device60. In the exemplary embodiment illustrated inFIG.14, the inflatable bladder62is generally triangular when expanded with a first side adjacent the lower surface54of the mattress34, a second side adjacent the bottom portion68of the mattress cover32, and a third side adjacent one of the peripheral portions70. The inflatable bladder62may be temporarily or permanently coupled to the lower surface54of the mattress34, such as with fasteners, sewing, radiofrequency or ultrasonic welding, and other joining means. It is contemplated that the inflatable bladder62may be in fluid communication with a fluid reservoir within the mattress34, such as with ports disposed on the lower surface54of the mattress34and the first side of the inflatable bladder62adjacent the lower surface54.

The aforementioned arrangement is such that the patient turning device60, and in certain embodiments the mattress34, is substantially encased within the mattress cover32. Thus, when the patient turning device60and the mattress34is substantially encased within the mattress cover32, it is understood that mattress cover32must expand or otherwise provide slack to prevent the mattress cover32from moving in response to expansion of the inflatable bladders62during the movement therapy. The mattress cover32includes the augmenting feature76associated with one of the peripheral portions70. The augmenting feature76is adapted to move between the stored configuration in the absence of the movement therapy, and the deployed configuration to accommodate the movement of the mattress34during the movement therapy in manners previously described. The augmenting feature76is represented schematically inFIG.14, and it is understood that the augmenting feature76may include any one or more aspects of the exemplary embodiments of the augmenting feature76described throughout the present disclosure.

Referring toFIG.15, the mattress cover32in accordance with another exemplary embodiment of the present disclosure is shown. The mattress cover32is formed from materials having different elasticity to concentrate elastic expansion during the movement therapy in a manner to be described. The mattress cover32includes the patient support portion44with the outer periphery74defined by the head end118, the foot end120, and opposing sides122of the patient support portion, as shown inFIG.15. The mattress cover32includes the bottom portion68coupled to the patient support portion44and adapted to cover the lower surface54of the mattress such that the mattress cover32substantially encases the mattress34between the patient support portion44and the bottom portion68.

The patient support portion44may be include a first area124formed from a first material having a first elasticity, and a second area126formed of a second material having a second elasticity. For example,FIG.15shows a pair of the first areas124each positioned adjacent to one of the opposing sides122of the patient support portion44. The second area126is positioned inwardly from the outer periphery74relative to the first area124. In certain embodiments, the second elasticity is less than the first elasticity such that, during the movement therapy, elastic expansion is concentrated to the first area124. The second area126may be positioned adjacent the head end118and the foot end120such that the second area126expands in response to increasing the thickness T of the mattress34to a lesser extent than the first area124. In other words, the mattress cover32includes discrete zones within the patient support portion44to localize expansion. The discrete zones may be within a single layer of the mattress cover32. It is understood that while two areas124,126are described, any number and/or location of areas may be provided having one or more respective elasticities to impart the desired expansive and other properties to the mattress cover32. For example, as shown inFIG.15, portions of the first area124extend to the peripheral portions70.

As mentioned, the first area124is formed of the first material with higher relative elasticity than the second material, and the first area124is positioned adjacent to the opposing sides122of the patient support portion44. With concurrent reference to, for example,FIGS.4B and14, the patient turning device60increases the thickness T of the mattress34(or moves the mattress34) with greater magnitude near the sides56of the mattress34. The first area124compensates, expands, or otherwise provides slack to prevent the mattress cover32from impeding increasing the thickness T of the mattress34or movement of the mattress34during the movement therapy. In some respects, the first area124having greater relative elasticity than the second area126may be considered another exemplary embodiment of the augmenting feature76. It is to be understood that the mattress cover32having areas124,126of different relative elasticities may be used in conjunction with any one or more aspects of the other exemplary embodiments of the augmenting feature76described throughout the present disclosure.

In certain embodiments, the first material has high breathability. One material having suitable breathability is Gore-Tex™ fabric manufactured by W. L. Gore & Associates, Inc. (Newark, Dela.). A moisture resistant layer may also be laminated with the mattress cover32to form a membrane, or alternatively the first area124may be thermally treated to modify the physical properties of the first material. In certain embodiments, the second area126has high elasticity. One material having suitable elasticity is Lycra® fabric, a registered trademark of Invista Inc. (Wichita, Kans.).

The first area124and/or the second area126may be fabricated from layers that are separately extruded then assembled by adhesion or thermal fusion. In another example, the layers are knit from yarns having different fiber properties such as fiber weight. The fibers may be arranged in three-dimensional layers to vary density, direction, and/or tension (e.g., anisotropic fibers). The fibers may be coated to further impart desired physical properties. In other examples, the fabrics may be laminated by spraying a screen print with materials having selected properties. It is further contemplated that advanced manufacturing techniques, such as three-dimensional printing, may also be implemented to tailor the location and orientation of the elastic expansion of the first material and/or the second material within the first area124and/or the second area126, respectively. Additive manufacturing techniques may provide for control of local surface shear and microclimate properties of one or more of the layers of the mattress cover32and/or the mattress34(see, for example,FIG.3).

The present disclosure contemplates that the advantageous features of the mattress cover32described throughout the present disclosure may be provided on a mattress overlay with the bottom portion68of the mattress overlay adapted to be positioned on and conformable to the upper surface52of the mattress34. The mattress overlay, including the mattress cover32, includes a cushioning layer (e.g., the mattress core layer66ofFIG.3), and a patient turning device60. The cushioning layer and the patient turning device60are disposed intermediate or between the patient support portion44and the bottom portion68positioned on the upper surface52of the mattress34. In other words, the cushioning layer and the patient turning device60may be considered substantially encased within the mattress cover32of the mattress overlay. The mattress overlay includes the augmenting feature76adapted to move between the stored configuration in the absence of movement therapy, and the deployed configuration in response to increasing the thickness of the mattress overlay positioned atop the mattress34.

It will be further appreciated that the terms “include,” “includes,” and “including” have the same meaning as the terms “comprise,” “comprises,” and “comprising.” Moreover, it will be appreciated that terms such as “first,” “second,” “third,” and the like are used herein to differentiate certain structural features and components for the non-limiting, illustrative purposes of clarity and consistency.

Several configurations have been discussed in the foregoing description. However, the configurations discussed herein are not intended to be exhaustive or limit the invention to any particular form. The terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations are possible in light of the above teachings and the invention may be practiced otherwise than as specifically described.

The invention is intended to be defined in the independent claims, with specific features laid out in the dependent claims, wherein the subject-matter of a claim dependent from one independent claim can also be implemented in connection with another independent claim.