Mattress section support

[0002] This application is a continuation-in-part of U.S. patent application Ser. No. 09/018,542, filed Feb. 4, 1998, now U.S. Pat. No. 6,163,903 the disclosure of which is expressly incorporated herein by reference, which is a continuation of U.S. patent application Ser. No. 08/511,711, filed Aug. 4, 1995, now U.S. Pat. No. 5,715,548, the disclosure of which is expressly incorporated herein by reference.

[0003] The present invention relates to beds. More particularly, the present invention relates to beds having a deck and a mattress positioned on the bedframe to provide a patient rest surface.

[0004] It is known to provide a bed including a bedframe having a deck. Furthermore, it is known to provide such a bed with a mattress positioned on the deck to define a patient rest surface. Typically, such mattresses have a compliant mattress section providing a resilient surface on which to support a patient.

[0005] According to the present invention, a bed is provided having a frame, a mattress section configured to define a patient rest surface, and a mattress section support. The frame includes a deck support and a step deck positioned on the deck support. The step deck has an upper deck, a lower deck, and a side wall. The upper deck is spaced apart from the lower deck to define a recess of the deck. The mattress section support is positioned between the mattress section and the step deck to support the mattress section over the recess in a position with a substantial portion of the mattress section positioned outside of the recess of the step deck.

[0006] According to other preferred aspects of the present invention, the mattress section support is positioned on the deck to support the patient rest surface above the recess of the step deck. The mattress section has a top surface, a bottom surface, and a side wall. The top surface of the mattress section provides the patient rest surface. The bottom surface of the mattress section is positioned over the upper deck. The mattress section support has a top surface and a bottom surface. The top surface of the mattress section support is positioned to support the mattress section over the recess. The mattress section support is also positioned above the lower deck to support the mattress section in a position substantially outside of the recess of the step deck in a position spaced apart from the lower deck of the step deck. According to alternative embodiments of the present invention, the mattress section support is either rigid or resilient.

[0007] Additional features of the disclosure will become apparent to those skilled in the art upon consideration of the following detailed description when taken in conjunction with the accompanying drawings.

[0008] The detailed description particularly refers to the accompanying figures in which:

[0009] FIG. 1 is a perspective view of a hospital bed having a bedframe including a deck, a set of siderails coupled to the deck, and a mattress positioned on the deck to provide a patient rest surface;

[0010] FIG. 2 is an exploded view of the bed of FIG. 1 showing the bedframe in a lowered position and the mattress including a mattress section and a pair of ridged plates positioned between the mattress section and the deck;

[0011] FIG. 3 is an assembly view showing the mattress section and a plurality of flat plates positioned to be coupled to the bottom of the mattress section;

[0012] FIG. 4 is an assembly view of the mattress section showing the various components thereof;

[0013] FIG. 5 is a perspective view of the step deck, with portions broken away, showing the ridged plates positioned on the step deck;

[0014] FIG. 6 is a cross-sectional view taken along line 6—6 of FIG. 5, showing the step deck, one of the flat plates positioned on the step deck; and the mattress section supported by the flat plate and one of the ridged plates;

[0015] FIG. 7 is an assembly view of an alternative embodiment mattress positioned over the step deck;

[0016] FIG. 8 is a cross-sectional view taken along line 8—8 of FIG. 7 showing the mattress of FIG. 7 positioned in the step deck; and

[0017] FIG. 9 is a cross-sectional view showing a siderail coupled to the articulating step deck.

[0018] A bed 10 in accordance with the present disclosure is provided having a head end 12, a foot end 14, and right and left sides 16, 18, as illustrated in FIG. 1. As used in this description, the phrase “head end 12” will be used to denote the end of any referred-to object that is positioned nearest to head end 12 of bed 10. Likewise, the phrase “foot end 14” will be used to denote the end of any referred-to object that is positioned nearest foot end 14 of bed 10.

[0019] Bed 10 includes a bedframe 20 having a base frame 22 and a deck support or intermediate frame 24 connected to base frame 22 as shown in FIGS. 1-2. Bedframe 20 further includes a step deck 26 coupled to intermediate frame 24. Bed 10 also includes head and foot end siderails 28, 30 coupled to step deck 26 and a mattress 32 positioned on step deck 26 that provides a patient rest surface 34 to support a person (not shown).

[0020] Mattress 32 includes a mattress section 36 and a cover 38 positioned around mattress section 36 as shown in FIG. 4. Mattress section 36 is resilient to provide a patient rest surface 33. Cover 38 protects mattress section 36 from becoming soiled during use and provides patient rest surface 34 of mattress 32. Mattress 32 also includes a set of mattress section supports 40 positioned on step deck 26 to support mattress section 36 on step deck 26 as shown in FIG. 2.

[0021] Bed 10 can assume a variety of positions such as a bed position, as shown in FIG. 1, and a chair position (not shown). Articulating step deck 26 includes a head section 42, a seat section 44, a thigh section 46, and a foot section 48. During movement of bed 10 between the various positions, deck sections 42, 44, 46, 48 move relative to one another. Head section 42, thigh section 46, and foot section 48 rotate relative to each other to change the angle of inclination of the back, thighs, and lower legs of the person (not shown) with respect to seat section 46. Additional description of the articulation of step deck 26 and the mechanisms that facilitate such movement are described in U.S. Pat. No. 5,715,548 (to Weismiller, et al.) filed Aug. 4, 1995, the disclosure of which is expressly incorporated by reference herein.

[0022] Additionally, step deck 26 includes an upper deck 50 and a central, longitudinally extending recess 52 defined by a lower deck 54 of step deck 26 and a side wall 56 surrounding recess 52 and connecting lower deck 54 to upper deck 50. As shown in FIG. 7, upper deck 50 includes longitudinally extending upper deck side portions 58, a head end upper deck portion 60 appended to a head end of head section 42, a foot end upper deck portion 62 appended to a foot end of intermediate frame 24 adjacent to thigh section 46, and side upper deck portions 64, 66, 68, 70, 72, 74 appended to sides of head, seat, and thigh sections 42, 44, 46. Upper deck portions 60, 64, 66, 68, 70, 72, 74, 62 and a top surface 76 of foot section 48 are coplanar when articulating deck 26 is in the horizontal position and cooperate to form upper deck 50 which is generally parallel to intermediate frame 24.

[0023] Lower deck 54 includes a head section 78, a seat section 80, and a thigh section 82. Head, seat, and thigh sections 78, 80, 82, are coplanar when articulating deck 26 is in the horizontal position and cooperate to form lower deck 54 which is generally parallel to intermediate frame 24 and to upper deck 50 when articulating deck 26 is in the horizontal position.

[0024] Lower deck 54 is connected to upper deck 50 by side wall 56 that includes a head end wall 84 connecting head section 78 to head end upper deck portion 60, side walls 86, 88, 90, 92, 94, 96 connecting head, seat, and thigh sections 78, 80, 82 to side upper deck portions 64, 66, 68, 70, 72, 74, and a foot end wall 98 connecting thigh section 82 to foot end upper deck portion 62 as shown in FIG. 7. Step deck 26, then, comprises upper deck 50 and is formed to include central, longitudinally extending recess 52 defined by lower deck 54 and by side wall 56 connecting lower deck 54 to upper deck 50. In the preferred embodiment, foot section 48 of step deck 26 is displaced from recess 52 and forms part of upper deck 50, as shown in FIGS. 2 and 7.

[0025] Head end siderails 28 are mounted to head section 42 of articulating deck 26, and foot end siderails 30 are mounted to intermediate frame 24 adjacent to thigh section 46 of deck 26. Step deck 26 cooperates with siderails 28, 30 to maximize the height relative to the patient rest surface 34 at which siderails 28, 30 are mounted as shown in FIG. 9. The tops of siderails 28, 30 are higher when in the patient-restraining position for improved coverage and protection of the person (not shown) on patient rest surface 34 and the bottoms can be higher when in the tucked position for improved access to base frame 22 and to the space beneath intermediate frame 24.

[0026] Head end siderails 28 are mounted to move with head section 42 as head section 42 pivots relative to intermediate frame 24 between a down position and a back-support position. Foot end siderails 30 are mounted to intermediate frame 24 and do not move relative to intermediate frame 24 and seat section 44 when head, thigh, and foot sections 42, 46, 48 of articulating deck 26 move.

[0027] As shown in FIG. 4, mattress section 36 includes several inflatable bladders 108 that provide support to a patient positioned on patient rest surface 34. Mattress section 36 also includes a pair of rotational bladders 110 used during rotational therapy of a patient positioned on mattress 32. According to alternative embodiments, other configurations of mattress sections are provided using components such as low air loss bladders, foam pads, fluidized bladders, or any other configuration that provides support for a patient positioned on the mattress section. According to other alternative embodiments, the mattress section is configured to have separate portions positioned over the head, seat, thigh, and foot sections of the deck. Thus, the mattress section may either contain a single component positioned over all the sections of the deck or multiple components positioned over one or more sections of the deck.

[0028] Cover 38 includes top and bottom sections 112, 114 as shown in FIG. 6. Top section 112 defines patient rest surface 34 and protects patient rest surface 33 of mattress section 36. Bottom section 114 defines a lower surface 118 positioned over upper deck 50 and a perimeter side wall 120. Top and bottom sections 112, 114 cooperate to define an interior region 122 of cover 38 in which air bladders 108 and rotational bladders 110 are positioned. As shown in FIG. 6, mattress section supports 40 are positioned outside and below cover 38.

[0029] Series of mattress section supports 40 are configured to support mattress section 36 in a position spaced apart from lower deck 54 so that mattress section 36 is positioned outside of recess 52 as shown in FIG. 6. Series of mattress section supports 40 includes five flat plates 124 coupled to cover 38 that extend across and over recess 52 to a position on top of respective portions 60, 62, 64, 66, 68, 70, 72, 74 of upper deck 50. Flat plates 124 are substantially rigid to provide support for mattress section 36 and to facilitate sliding of mattress 32 off of step deck 26. Further description of flat plates 124 and mattress 32 is provided in U.S. Pat. No. 6,021,533 to Ellis et al., filed Aug. 25, 1997, the disclosure of which is expressly incorporated herein by reference.

[0030] Series of substantially rigid mattress section supports 40 further include a pair of ridged plates 126 positioned on lower deck 54, as shown in FIG. 5. Ridged plates 126 extend up from lower deck 54 to support flat plates 124 and mattress section 36 so that mattress section 36 is positioned outside of recess 52 as shown in FIG. 6. According to alternative embodiments, the mattress sections are semi-rigid, partially rigid, compliance, or any other suitable stiffness.

[0031] Each flat plate 124 is coupled to lower surface 118 of bottom section 114 of cover 38 by snaps 128 as shown in FIG. 3. Each flat plate 124 includes an upper surface 130 positioned adjacent to lower surface 118 of top section 112 of cover 38 and a downwardly facing lower surface 132 positioned on and adjacent to upper deck 50 so that flat plates 124 are positioned between mattress section 36 and step deck 26, as shown, for example, in FIG. 6.

[0032] Each flat plate 124 is substantially rigid to support mattress 32 and to facilitate sliding of mattress section 36 off of step deck 26. When a patient is positioned on mattress 32, flat plates 124 may bow under the weight of the patient so that a portion of mattress section 36 is positioned in recess 52. Ridged plates 126 are provided to provide additional support for mattress section 36 so that flat plates 124 bow only slightly, or not at all, when a patient is positioned on mattress section 36. Rigid plates 126 also provide support to plates 124 and mattress section 36 when mattress section 36 is slid off of step deck 26. According to alternative embodiments of the present disclosure, ridged plates are not provided so that flat plates are the only support of the mattress section over the lower deck.

[0033] As shown in FIGS. 5 and 6, ridged plates 126 are positioned on lower deck 54 of step deck 26 within recess 52. Each ridged plate 126 includes a base 134 positioned on lower deck 54 and a pair of upwardly extending ridges 136. Base 134 has a length 138 substantially equal to an internal width 140 of lower deck 54 and a length 142 of sections 78, 80, 82. Base 134 also includes a width that is slightly less than a width of respective sections 78, 80, 82. Thus, each base 134 covers a substantial portion of the respective deck sections 78, 80, 82 of lower deck 54.

[0034] As shown in FIGS. 2 and 5, each base 134 includes a pair of notches 148 sized to provide clearance for hinges 150 of step deck 26. Ridges 136 cooperate to define a top surface 152 of ridged plates 126 that has a height 154 substantially equal to a height of side walls 156 of step deck 26 so that top surface 152 of ridged plates 126 is substantially coplanar with upper deck 50 as shown in FIG. 6. Because upper deck 50 and top surface 152 of ridged plates 126 are coplanar, perimeter portions 155 and middle portions 156 of flat plates 124 are supported at substantially the same height. Side walls 158 of ridged plates 126 are provided with corrugations 160 to provide additional rigidity to ridges 136.

[0035] As shown in FIG. 6, ridged plates 126 do not fill recess 52 so that a substantial portion of recess 52 remains a void. According to alternative embodiments, substantially rigid members are provided that substantially fill recess 52.

[0036] Ridged plates 126 are also provided with tethers 162 coupled near the bottom of ridges 136 and to straps 164 of mattress section 32. Tethers 162 align ridged plates 124 with deck sections 78, 80, 82 so that during articulation of step deck 26, ridged plates 126 remain in proper orientation. One end of each tether 162 is provided with a clip 166 to facilitate attachment of tethers 162 to straps 168.

[0037] A mattress 232 according to an alternative embodiment is shown in FIG. 7. Mattress 232 includes a mattress section 236 having a generally upwardly-facing sleeping surface 234 and a bottom surface 242 that is generally parallel to sleeping surface 234 and that is positioned beneath sleeping surface 234. A perimetral side 244 connects sleeping surface 234 and bottom surface 242. A mattress section support 240 is appended to bottom surface 242 of mattress section 236 and extends downwardly therefrom. Preferably, mattress section support 240 is spaced-apart from sides 244 of mattress section 236 and nests in recess 52. Mattress section support 240 may engage side wall 56 of step deck 26 to prevent movement of mattress section 236 relative to step deck 26 and to maintain the generally central position of mattress 232 on deck 26.

[0038] Because mattress section support 240 is positioned under mattress section 236, mattress section support 240 prevents a substantial portion of mattress section 236 from sagging into recess 52 when no patient is positioned on bed 10. Thus, mattress section support 240 positions mattress section 236 in a location spaced apart from lower deck 54. However, when a patient is positioned on bed 10, the weight of the patient will compress mattress section 236 and mattress section support 240 permitting a portion of mattress section 236 to sag into recess 52. Thus, mattress section support 240 is compliant to provide resilient support of mattress section 236. According to alternative embodiments, the mattress section support positioned in the cover is rigid, semi-rigid, partially rigid, or any other suitable stiffness.

[0039] Preferably, mattress section 236 and mattress section support 240 cooperate to provide mattress 232 with a thick zone 246 positioned partially within recess 52. Mattress section 236 provides mattress 232 with a thin zone 248 engaging upper deck 50 as shown in FIG. 8. For example, thick zone 246 can be one and one-half times the thickness of thin zone 248. In one preferred embodiment, the thick zone is approximately 7½ inches (19 cm) thick and the thin zone is 5 inches (12.7 cm) thick. Thick zone 246 is positioned to carry the majority of the weight of a person (shown in phantom) supported on sleeping surface 234 to maximize the comfort of the person. Having perimetral thin zone 248 provides a perimetral portion of mattress 232 that appears to the person on sleeping surface 234 to be firmer than thick zone 246, facilitating entry onto and exit from sleeping surface 234 along sides 244 of mattress 232.

[0040] Thinner perimetral zone 248 and upper deck side portions 58 cooperate to define edges that provide greater firmness around the edges of sleeping surface 234 as the result of sleeping surface 234 being in close proximity to upper deck 50. This increased firmness is advantageous when the person enters and exits the bed along the sides of the bed. Additionally, the edges provide a firm edge that cooperates with siderails 28, 30 to minimize the potential for side rail entrapment, in which an object becomes wedged between sleeping surface 234 and one of siderails 28, 30.

[0041] Mattress section support 240 includes a side wall 258 that can be configured to engage at least portions of side wall 56 of step deck 26 as shown in FIG. 8, thereby preventing lateral and longitudinal sliding of mattress 232 relative to step deck 26. Also, mattress section 236 includes sides 244 connecting sleeping surface 234 and bottom surface 242. Mattress 232 and step deck 26 are configured so that sides 244 of mattress section 236 are exposed above deck 26 as shown in FIGS. 8 and 9 providing the caregiver greater and easier access to mattress 232, rather than engaging a portion of a frame or upstanding walls of a deck as is found with conventional mattress and deck systems.

[0042] Mattress section 236 and mattress section support 240 may be provided in more than one piece, for example, mattress 232 may comprise a first mattress piece fit into recess 52 and a second mattress piece surrounding and abutting sides of the first mattress piece and engaging upper deck 50, or a first mattress piece (the mattress section support) could fit into recess 52 and a second mattress piece (the mattress section) having a planar bottom surface could fit over the first mattress piece so that the bottom of the second mattress piece engages the first mattress piece and upper deck 50. However, a one-piece mattress 232 including both mattress section 236 and mattress section support 240 is preferred.

[0043] Mattress 232 further includes a cover 238 defining upper or support surface 234, a perimeter side wall 216, and a lower surface 218. Upper and lower surfaces 234, 218 and sidewall 216 cooperate to define an interior region 222 and to enclose mattress section 236 and mattress section support 240 within cover 238.

[0044] Although the invention has been described in detail with reference to preferred embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.