MXPA98000966A - Mattress for bed of hospi - Google Patents

Abstract

The present invention relates to a mattress for use with a stepped platform having an upper deck or platform, a lower deck or platform coupled to the upper deck or platform by means of a side wall of the platform, so that the cover or lower platform is separated from the cover or upper platform to define a cavity of the stepped platform, the mattress is characterized in that it comprises: a surface for supporting a patient, oriented upwards, generally flat, and a lower surface oriented downward, stepped, including a perimeter portion extending downwardly from the surface to support the patient a first depth and a central projection extending downward from the surface to the patient a second depth greater than the first depth, a lower surface of the perimeter portion is configured to rest on the deck or platform The upper surface, a lower surface of the central projection is configured to rest on the lower deck or platform, and a side wall of the central projection is configured to be located adjacent to the side wall of the platform to maintain the mattress on the stepped platform, reducing by therefore at a minimum a distance that the surface that supports the patient covers the upper deck or platform

Description

MATTRESS FOR HOSPITAL BED Background and Brief Description of the Invention The present invention relates to a mattress, and in particular to a mattress for hospital bed and other devices on which patients recline including, for example, examination columns and tables. More particularly, the present invention relates to a mattress for hospital beds including beds that can be manipulated to achieve both a conventional bed position, which has a horizontal sleeping surface and a seating position, which moves the The person's feet on or adjacent to the floor and the head and back of the person supported on top of a seat formed by the bed. Examination beds and tables having mattresses resting on adjustable articulated platforms are known in the art. See, for example, U.S. Patent Nos. 5,077,843 to Foster, L. Dale et al., 5,157,800 to Borders, and 5,129,177 to Celestina et al., All of which were granted to the beneficiary of the present invention, and US Pat. Nos. 5,279,010 by Ferrand et al., 4,133,109 by Howell, 4,411,035 by Fen ick, and 3,220,022 by Nelson, as well as the publication REF: 26318 German No. 716981. Each of these references describes a bed or an examination table that includes a mattress which has an upper surface that is articulated to adjust the position of the person on the surface. See also U.S. Patent Application No. 08 / 511,711 filed on August 4, 1995, of Weismiller et al., And entitled "Bed Chair", the specification of which is incorporated herein by reference. According to the present invention, a mattress for bed is provided. The mattress includes an upwardly oriented, generally flat resting surface or sleeping surface, for supporting a person and a lower, stepped, lower surface. The lower surface includes a perimeter portion g? E extending downwardly from the support surface a first depth and a central projection extending downwardly from the support surface a second depth, which is greater than the first depth. The illustrative bed on which such a mattress is used includes a base frame, an intermediate frame coupled to the base frame, a load or weight frame coupled to the intermediate frame, and an articulated cover coupled to the load or weight frame. The mattress of the present invention rests on the articulated platform.

The illustrative articulated platform has longitudinally spaced sections of head, buttocks, thighs and feet. The head sections, buttocks and feet move in mutual relation and move relative to the buttock section, which is fixed in relation to the load or weight frame. The head, thigh and foot sections are infinitely adjustable to allow the chair to reach any desired position within the range of movement of the head, thigh and foot sections, thereby accommodating changes in a person's position on the chair bed. The mattress is suitable for use with such an articulated platform. The mattress includes a head portion, a portion of buttocks, a portion of thighs, and a portion of feet. Each portion of the combined mattress is associated respectively with the head, buttocks, thighs and feet of the person resting on the sleeping surface of the bed as well as with the head sections, buttocks, thighs and underlying feet of the platform. The illustrative articulated platform containing the mattress can be a longitudinally stepped platform including upper platform side portions and a central cavity, which extends longitudinally between the side portions. The cavity is defined by a lower platform and the side walls connecting the lower platform and the upper portion of the platform. The mattress includes a sleeping surface facing upwards, a lower surface, sides connecting the sleeping surface and the lower surface, and a downwardly extending projection attached to the lower surface and extending down therefrom. During use, the projection is received by the cavity and the stepped platform. If desired, the projection can be nested in the cavity and coupled to at least a portion of the side wall of the platform. The central portion of this mode can cooperate with the side walls defining the cavity to prevent movement of the mattress in relation to the bed. The stepped platform and a mattress configured for use with the stepped platform can be used independently of the bed and the articulated platform. For example, a stepped platform and accompanying mattress may be provided for a stretcher, examination table, or any device on which a patient rests. A stretcher, for example, may include a frame, a stepped platform mounted to the frame, the stepped platform has longitudinal upper side portions that engage the frame, and a mattress having a generally flat sleeping surface and a lower surface including a projection configured such that the shape of the lower surface generally conforms to the shape of the stepped platform. In the same way, a stepped platform and associated mattress for a stretcher could be provided. Such a stretcher could be similar to the illustrative stretcher described above except that the frame could include wheels so that the stretcher can be transported by rolling it from one place to another. In the preferred embodiments of the mattress, the sleeping surface is generally flat and the projection is located in the center below the sleeping surface to form a centrally located portion, thick, of the mattress. The variable thickness of the mattress provides the mattress with "zones" that include a zone to support the body, thick, adjacent to the projection and a thin area in areas far from the projection. The mattress portion adjacent the upper cover portions forms a thin peripheral end coupled to the upper platform portion. The projection typically includes portions of the area of the lower surface of the mattress in the head portion, the portion of the buttocks, and a portion of thighs. The thinner zone typically covers the foot portion of the mattress and a perimeter zone of the mattress along the sides of the thigh, buttock and head portions as well as the upper end of the head portion of the mattress. As a result, the thin area typically encompasses most of the portion of the mattress that will mostly hold the weight of the person on the sleeping surface and the thin area surrounds the thick area. Additionally, the thin perimeter zone of the mattress adjacent to the upper platform portions of the articulated platform cooperate with the upper platform portions to provide "tamped edges" that increase the firmness experienced by the person around the edges of the mattress. The mattress cooperates with the stepped platform to present a generally flat top surface while also providing the thin perimeter zone that results in the tamped edges. This increased firmness is advantageous when the person enters and exits the bed along the sides of the bed. The mattress can be provided in more than one piece, for example, a first piece of the mattress could be adjusted in the cavity and a second piece of the mattress could be attached to the upper platform portion and surround the first piece of the mattress, or a first piece of the mattress could be adjusted in the cavity and a second piece of the mattress could cover the first piece of the mattress and be attached to the upper platform portion. Although there are many potential variations of the stepped platform shape and the corresponding mattress shape and the numbers and types of mattress pieces that could be generated, no stepped platform has a top platform portion or a cavity defined by a lower platform portion and walls connecting the lower and upper platform portions that could achieve the desired results. Similarly, any mattress or combinations of mattress pieces that provide a lower surface that is generally configured in the form of the stepped platform could achieve the desired results. Therefore, an object of the present invention is to provide a mattress for use in a bed for the care of a patient. The patient care bed has a longitudinally extending patient support platform with longitudinally extending raised upper platform portions extending along its sides. The mattress comprises a longitudinally extending central body portion that must be placed on the support platform and the side portions must be placed on the upper platform portions. The central body portion has a depth greater than the depth of the lateral portions. Another object of the present invention is to provide such a mattress having a deflatable standing portion. The mattress comprises a generally flat surface for the patient and portions of the head, buttocks, thighs and feet. The foot portion is deflatable and has a first length when deflated and a second length when inflated, so that the second length is greater than the first length. In addition, the foot portion may be configured to have a first height when deflated and a second height when inflated, the second height being greater than the first height. In preferred embodiments, the foot portion of the mattress is inflated when the foot section is in the upper position. When the foot portion of the mattress is inflated, the sleeping surface of the mattress adjacent to the foot section is generally flat with the sleeping surface adjacent to the other sections of the platform. Illustratively, the foot portion of the mattress deflates and inflates automatically and inflates and deflates when the foot section of the platform rotates between the upper and lower positions. The objects, features and additional advantages of the invention will be apparent to those skilled in the art upon consideration of the following detailed description of the specific embodiments that exemplify the best mode of carrying out the invention as it is perceived so far.

Brief Description of the Drawings The detailed description particularly refers to the accompanying figures in which: Figure 1 is a perspective view of a bed chair according to the present invention showing the exploded view of a side rail away from the chair, the handrails laterals of the head and side rails of the feet placed along the longitudinal sides of the platform, and showing a bridge for the feet in closed position; Figure 2 is a view similar to Figure 1 showing the bed chair in the sitting position having a head position of an articulated platform moved up towards a back support position, a section of thighs of the platform slightly tilted upward, a section of feet of the platform moved to a downward position that extends generally vertically downward, a portion of feet of the mattress is deflated, and the bridges rotated to an open position with a bent rotating bridge next to the bed chair; Figure 3 is a schematic view of the bed chair of Figure 1 showing the bed chair in a bed position including a mattress having an upwardly facing sleeping surface maintained at a predetermined first distance above the floor, the the platform is in an initial position that supports the sleeping surface in a generally flat configuration, and the foot section is of a first length; Figure 4 is a schematic view showing the bed chair in a lower position; Figure 5 is a schematic view showing the bed chair in a Trendelenburg position; Figure 6 is a schematic view showing the bed chair in an inverted Trendelenburg position; Fig. 7 is a schematic view showing the bed chair in an intermediate position having an upper end of the head section of the platform turned slightly upwards from the initial position of the platform, a section of buttocks positioned to remain in the horizontal plane defined by the section of buttocks in the initial section of the platform, and the foot section is slightly inclined, so that the foot end of the foot section is below the foot section when the platform it is in the initial position of the platform; Figure 8 is a schematic view showing the chair in a chair or seat position with the upper end of the head section turned upward from the buttock section to a back support position, the buttock section being located generally horizontal as in the initial platform position, the thigh section rose up, the foot section extends down from the thigh section and is a second shorter length, and the mattress portion over the foot section deflated; Figure 9 is a perspective view of a first embodiment of a stepped platform and a mattress according to the present invention; Figure 10 is a sectional view taken along line 10-10 of Figure 9 showing the bottom of the stepped platform below the projection; Figure 11 is an exploded perspective view of a second embodiment of a stepped platform and the mattress of the chair; Figure 12 is a sectional view taken along line 12-12 of Figure 11 of the stepped platform and mattress and showing a C-shaped arm (shaded) for holding medical equipment such as fluoroscopic equipment; Figure 13 is an exploded perspective view of a third embodiment of the mattress and platform showing the foot section of the platform and the foot portion of the mattress in a minimized condition having the foot section of the contracted platform and the foot section of the mattress contracted longitudinally and deflated, so that the foot portion of the mattress is thinner and shorter than when the foot portion is inflated; and Figure 14 is a schematic view further illustrating how the foot section of the surface retracts or shortens and collapses or thins when the bed moves from the bed position to the chair position.

Detailed Description of Illustrative and Preferred Modalities A bed chair 50 according to the present invention having a head end 52, an end of feet 54, and sides. 56, 58 are illustrated in Figures 1 and 2. As used in this description, the phrase "head end 52" will be used to denote the end of any referred object that is placed to be close to the end of the head 52 of the bed chair 50. Similarly, the phrase "foot end 54" will be used to denote the end of any referenced object that is placed to be near the end of the feet 54 of the bed seat 50. The bed seat 50 includes a base module 60 having a base frame 62 connected to an intermediate frame module 300 as shown in Figure 1. An articulated platform module / load frame or weight 400 is coupled to the intermediate frame module 300. side rail assemblies 800, 802, 804, 806 and an extended frame module 610 having a rotating foot bridge 622 are coupled to the articulated platform module / load frame or weight 400. A mattress 550 is supported by the mobile articulated platform module / load frame or weight 400 and provides a sleeping surface or support surface 552 configured to receive a person (not shown). The bed chair 50 can be manipulated by a nurse or by a person (not shown) on the sleeping surface 552 using the hydraulic system module (not shown) so that the mattress 550, the intermediate frame 302 of the intermediate frame 300, and an articulated platform 402 of the articulated platform module / load or weight frame 400 tune a variety of positions, several of which are shown schematically in Figures 3-7. The articulated platform 402 includes a head section 404, a buttock section 406, a thigh section 408, and a foot section 410. The mattress 550 rests on the platform 402 and includes a head portion 558, a portion of buttocks 560, a portion of thighs 562, and a portion of feet 564, each of which generally corresponds to portions of platform 402 named equally, and each of which is generally associated with the head, buttocks, thighs and feet of the person on the sleeping surface 552. The details of the platform 402 and the mattress 550 will be explained here below. The bed chair 50 can assume a bed position having the platform 402 configured such that the sleeping surface 552 is flat and horizontal, defining an initial portion of the platform 402 as shown in Figure 1 and as schematically shown in FIG. Figure 3. In the bed position, the sleeping surface 552 is a first predetermined distance 566 above the floor. The bed chair 50 can also be manipulated to assume a low position shown schematically in Figure 4 having a platform 402 in the initial position and having a sleeping surface 552 at a second predetermined distance 568 above the floor, the second distance 568 is smaller than the first distance 566. The foot section 410 of the articulated platform 402 has a first length 465 when the platform 402 is in the initial position. The bed chair 50 can be moved to a Trendelenburg position shown schematically in Figure 5 having the platform 402 in the flat, inclined configuration so that the end of the head 52 of the sleeping surface 552 is positioned to be closer of the floor that the end of the feet 54 of the sleeping surface 552. The bed chair 50 can also reach an inverted Trendelenburg position shown schematically in Figure 6 having the platform 402 in a flat and inclined configuration so that the end of the feet of the sleeping surface 54 is positioned to be closer to the floor than the end of the head 52 of the sleeping surface 552. As described above, the bed chair 50 is convertible to a seating position shown in Figure 2 and shown schematically in Figure 8. In the seating position, the head end 52 of the head section 404 of the platform 402 is rotated towards above the intermediate frame 302 to a back support position providing a rotatable backrest so that the head section 404 and the intermediate frame 302 form an angle 512 generally between 55 and 90 degrees. The buttock section 406 of the platform 402 is positioned to be generally horizontal as in the initial position, the end of the feet 54 of the thigh section 408 is tilted slightly upward, and the foot section 410 of the platform 402 it extends generally vertically downwardly from the thigh section 408 and has a length 464 that is shorter when the platform 402 is in the initial position. The foot portion 564 of the mattress 550 is inflatable and is in a deflated condition when the bed seat 50 is in the seating position. The foot portion 564 of the 550 mattress is thinner and shorter when it is deflated than when it is inflated. The bed chair 50 is capable of assuming positions in which the head, thigh and foot sections 404, 408, 410 of the platform 402 are in intermediate positions to those shown in Figures 3 and 8. For example, the bed chair 50 can assume an intermediate position shown in Figure 7 having the head end 52 of the head section 404 of the platform 402 slightly turned upward from the initial position, the seat section 406 positioned to lie in the same generally horizontal plane as in the initial position, the foot end 54 of the thigh section 408 raised slightly upwards from the starting position, in the foot section 410 being inclined so that the foot end 54 of the foot section 410 is Further, the hinged form 402 of the bed chair 50 is configured as a stepped platform 402 as illustrated. together with the illustrative stepped mattress 550 in Figures 9, 10, and 11-13. The staggered platform and mattress of Figures 11-13 are those illustrated in Figures 3-8. The stepped platform 412 includes an upper deck or platform 414 and a longitudinally extending central cavity 456 defined by a lower platform or deck 430 of the stepped platform 412 and a wall 438 surrounding the cavity 456 and connecting the deck or platform bottom 430 to the upper deck or platform 414. The upper deck or platform 414 includes longitudinally extending upper platform or deck portions 417, an upper deck portion or top platform of the head end 416 and an end portion of cover or upper platform of the foot end 460. The mattress 550 includes a generally upwardly facing sleeping surface 552 and a lower surface 586 that is generally parallel to the sleeping surface 552 and that is positioned to lie below the sleeping surface 552. A perimeter side 578 connects the sleeping surface 552 and a lower surface 586. A projection 576 is attached to the lower surface 586 and extends downwardly thereof. Preferably, the projection 576 is spaced from the sides 578 of the mattress 550 and nested in the cavity 456. The projection 576 can couple the wall 438 of the stepped platform 412 to prevent movement of the mattress 550 in relation to the stepped platform 412 and to maintain the generally central position of the mattress 550 on the platform 412. Preferably, the mattress 550 is provided with a thick zone 582 adjacent the cavity 456 and a projection 576, and a thin zone 580 that couples the cover or upper platform 414 as shown in Figure 10. For example, the thick zone 582 may be one and a half times thicker than the thin zone 580. In a preferred embodiment, the thick zone is approximately 7 1/2 inches (19 cm) thick and the thin zone is 5 inches ( 12.7 cm) thick. The thick zone 582 is positioned to support most of the weight of a person (shown in shaded form) supported on the surface to -smooth 552 to maximize the comfort of the person. In contrast, the thin perimeter zone 580 provides a perimeter portion of the mattress 550 which makes it appear that the person on the sleeping surface 552 is firmer than in the thick zone 582, facilitating the entry and exit of the sleeping surface 552 a along the sides 578 of the mattress 550. As can be seen, the stepped platform 414 and the mattress 550 can be used in many applications that require a support surface to support a person. For example, step platform 414 and mattress 500 can be configured to be used as a stretcher to be carried by stretchers and as a stretcher having a stepped platform 414 mounted on a frame with wheels to carry the person supported on the stretcher. The articulated platform 402 is on the surface on which the mattress 550 rests as shown in Figures 11-13. The platform 402 is segmented illustratively in the head, buttock, thigh and foot sections 404, 406, 408, 410, three of which, the head section 404, thigh section 408, and foot section 410, can be rotated to change the angle of inclination of the back, thighs and legs of the person (not shown) with respect to the buttocks section 408. The butt section 406 of the platform 402 remains horizontal and the head, thigh and foot sections 404, 408 and 410 of the platform 402 can move relative to the buttock section 406 and in mutual relation, thereby moving the head, thigh and foot portions 558, 562, 564 of the mattress 550 relative to the portion of 560 mattress pad 550 and in mutual relation. The head, buttock, thigh and foot sections 404, 406, 408, 410 of the articulated platform 402 cooperate to define the stepped platform 412 as shown in Figures 11-13. The stepped platform 412 includes a top deck or platform 414 having a top deck or platform portion of the head end 416 attached to the head end 52 of the head section 404, side deck or top platform portions 418, 420 , 422, 424, 426, 428 attached to the sides of the head sections, buttocks, and thighs 404, 406, 408, and a top deck or platform portion of the end of the feet 460 attached to the foot end 54 of the load frame or weight 506 adjacent to the thigh section 408. The portions of the upper deck or platform 416, 418, 420, 422, 424, 426, 428, 460 and an upper surface 411 of the foot section 410 are coplanar when the articulated platform 402 is in the initial position and cooperate to form the upper deck or platform 414 which is generally parallel to the load frame or weight 506. A stepped platform 412 also includes a cover or plat lower form 430 having a head splint 432, a splint for the buttocks 434 and a thigh splint 436. The splints for the head, buttocks and thighs 432, 434, 436, are coplanar when the articulated platform 402 located in the initial position and cooperate to form the lower platform cover 430 which is generally parallel to the load frame or weight 506 and to the upper deck or platform 414 when the articulated platform 402 is in the initial position. The lower deck or platform 430 is connected to the upper deck or platform 414 by a wall 438 that includes an upper end wall 440 that connects the head board 432 to the portion of the upper deck or platform of the end of the head 416, side walls 442, 444, 446, 44, 450, 452 connecting the head slats, buttocks and thighs 432, 434, 436 to the upper, platform or side deck portions 418, 420, 422, 424, 426, 428, and a lower end wall 454 that connects the thigh board 436 to the portion of the upper deck or platform of the foot end 460 as shown in Figure 11. The stepped platform 412, then, comprises the cover or upper platform 414 and is formed to include a longitudinally extending central cavity 456 defined by the lower deck or platform 430 and by the wall 438 connecting the lower deck or platform 430 to the upper deck or platform 414. In the preferred embodiment, the foot section 410 of the upper deck or platform 412 is displaced from the cavity 456 and forms part of the upper deck or platform 414, as shown in Figures 11 and 13. The mattress 550 is received by the platform. The articulated orifice "02" includes a projection 576 dimensioned to be received by the cavity 456 as shown in Figures 11 and 12. Consequently, the mattress 550 is thinner along the sides 580 of the mattress 550 where the mattress 550 engages the upper deck or platform 414 of the stepped platform 412. Conversely, the mattress 550 is thicker in the portions adjacent to the projection 576. Preferably, the projection 576 is positioned directly below the portions of mattress 550 that supports most of the weight of the person on the sleeping surface 552. The thick portion of the mattress 550 includes the thickness of the mattress 550 between the sleeping surface 552 and the lower surface 586 that couples the upper deck or platform 414 plus the thickness of the projection 576 provides greater comfort to the person on the surface to sleep 552. The mattress 550, then, has a perimeter zone more delg ada 580 and a region supporting the body 582, thicker, adjacent to the projection 576. Preferably, the area supporting the body is 1 1/2 times the thickness of the perimeter 580. For example, the perimeter zone It can be 5 inches (12.7 cm) thick and the area supporting the body 582 can be 7 1/2 inches (19 cm) thick. The thinner perimeter region 580 and the side portions of the upper deck or platform 417 cooperate to define "tamped" edges that provide greater firmness around the edges of the sleeping surface 552 as a result of which the sleeping surface 552 is in close proximity to the upper deck or platform 414. This greater firmness is advantageous when the person enters and goes to bed along the sides of the bed. The projection 576 includes a side wall 584 that can be configured to engage at least portions of the wall 438 of the step platform 412 as shown in Figure 12, thereby preventing lateral and longitudinal sliding of the mattress 550 relative to the step platform 412. Also, the mattress 550 includes the sides 578 connecting the sleeping surface 552 and the lower surface 586. The mattress 550 and the stepped platform 412 are configured so that the sides 578 of the mattress 550 are exposed on top of the mattress 550. platform 402 as shown in Figures 11 and 12 providing the stretcher greater and easier access to the mattress 550, instead of attaching a portion of a frame, or vertical walls of a platform as it meets the mattress systems and conventional platform. In preferred embodiments, the sleeping surface 550 is generally planar and the projection 576 is located in the center below the sleeping surface 550 to form a thick, body-supporting zone 582 of the mattress 550 surrounded by the perimeter zone 580 which engages the upper deck or platform 414. The mattress 550 can be provided with more than one piece, for example, the mattress 550 may comprise a first piece of mattress placed in the cavity 456 and a second piece of mattress surrounding and in contact with the sides of the first piece of mattress and engaging the top deck or platform 414, or a first piece of mattress could be placed in the cavity 456 and a second piece of mattress having a flat bottom surface could be placed on the first piece of mattress, so that the bottom of the second piece of mattress engages the first piece of mattress and the upper deck or platform 414. However, a one-piece mattress 550 is preferred which includes a body supporting area 582 and a perimeter zone 580. Additionally, the mattress 550 may include an inflatable portion 574 that can assume a inflated position and a deflated position. Preferably, the inflatable portion 574 is positioned to lie on the foot portion 564 as shown in Figure 13, so that the inflatable portion 574 can be inflated to serve as a sleeping surface 552 when the foot section 410 of the platform 402 is in the upper position and so that the inflatable portion 574 can be deflated and tilted downward when the foot section 410 is lowered towards the lower position to provide accommodation to the lower part of the person's legs when the 50 bed chair is in the seating position. The portion of feet 564 is thinner and shorter when it deflates than when the portion of feet 564 is inflated. The foot portion 564 of the mattress 550 and the foot section 410 of the articulated platform 402 cooperate to minimize the length at the feet of the bed chair 50 as shown in Figure 13. The foot section 410 and the portion of feet 564 has a first length 465 when the foot section 410 is in the upper position and a second length 464 when the foot section 410 is in the lower position, the first length 465 is greater than the length 464. , the foot position 564 has a first thickness 608 when the foot section 410 is in the upper position and a second thickness 609 when the foot section 410 is in the lower position, the first thickness 608 is greater than the second thickness 609. In addition, the width 604 of the foot portion 564 of the mattress 550 is less than the width 606 of the head portion 558 of the mattress 550, the width 606 of the head portion 558 is typically a width of 20 cm. standard chon as shown in Figures 11 and 13. This difference between the widths 604, 606 allows a standard fitted sheet (not shown) to be previously installed on the mattress 550 while remaining loose adjacent to the foot portion 564, of so that the pressure released can be maintained in the section of the portion of feet 564 that receives the hips (not shown) of the person (not shown) supported on the sleeping surface 552. In the preferred embodiments, the portion of defibrillating feet 564 includes a first set of airbags 1618 and a second set of airbags 1620 alternately positioned with the airbags 1618 as shown in Figure 14. The airbags 1618 and 1620. are configured to collapse to a dimension close to zero when the air is extracted from the bags 1618 and 1620. The first set of bags 1618 is oriented to collapse in a first direction which is generally parallel to the foot section 410 of the platform 402 as illustrated by the double-headed arrow 1622. The second set of bags 1620 is configured to be placed in a second direction generally perpendicular to the deck section or platform for the feet 410 as illustrated by the double-headed arrow 1624. This orientation of the bags 1618 and 1620 in the foot section 1502 advantageously makes the foot section 1502 contract or shorten and collapse or thin out when the bags 1618 and 1620 they are deflated when the foot section 410 moves from the upper position to the lower position. In the seat position, the foot section 410 and the foot portion 564 of the mattress 550 move from a generally horizontal position to a generally vertical position, which extends downward. The foot portion 564 deflates as it moves from the upper position to the lower position in the direction of the arrow 1626 as shown in Figure 14. In the upper position, the foot portion 564 has a length of approximately 27 inches (68.6 cm) and a thickness of approximately 5 inches (12.7 cm) when bags 1618 and 1620 are fully inflated. When in the lower position illustrated at 1628 in Figure 14, the foot portion 564 is completely deflated and has a length of about 14 inches (35.6-cm) and a thickness preferably less than 1 inch (2.54 cm). The length of the foot section of the surface is preferably reduced by at least 40% and the thickness of the foot section of the surface is preferably reduced by at least 80% when the foot portion 564 is moved towards the lower position. The width of the foot portion of the surface 564 remains substantially the same in both the upper and lower positions. Although the invention has been described in detail with reference to the preferred embodiments, there are variations and modifications within the scope and spirit of the invention as described or defined in the following claims.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates. Having described the invention as above, property is claimed as contained in the following:

Claims (26)

1. A mattress for use with a stepped platform having an upper deck or platform, a cover or lower platform coupled to the upper deck or platform by means of a side wall of the platform, so that the lower deck or platform is separated from the cover or upper platform to define a cavity of the stepped platform, the mattress is characterized in that it comprises: a surface for supporting a patient, oriented upwards, generally flat, and a lower surface oriented downward, stepped, including a perimeter portion qe it extends down from the surface to support the patient a first depth and a central projection extending down from the surface to the patient a second depth greater than the first depth, a lower surface of the perimeter portion is configured to rest on the deck or upper platform, a surface in The bottom of the central projection is configured to rest on the lower deck or platform, and a side wall of the central projection is configured to be located adjacent to the side wall of the platform to maintain the mattress on the stepped platform, thereby reducing the minimum a distance that the surface that supports the patient covers the upper deck or platform.

2. The mattress according to claim 1, characterized in that the mattress includes a head, body and foot portion and the portion of the projection forms a substantial portion of the head and body portions.

3. The mattress according to claim 2, characterized in that a portion of the perimeter portion forms the portion for the feet.

4. The mattress according to claim 1, characterized in that the projection portion is twice the depth of the perimeter portion.

5. A mattress, characterized in that it comprises a surface for a patient, oriented upwards, generally flat, and a bottom surface oriented downward, stepped, including a perimeter portion extending downwardly from the surface to support the patient to a first depth and a central projection extending down from the surface to the patient a second depth greater than the first depth the mattress further includes portions of head, buttocks, thighs and feet, at least one such portion is inflatable.

6. The mattress according to claim 5, characterized in that the projection is positioned to lie below the head portion, the buttock portion and the thigh portion, and the projection is separated from the foot end.

7. The mattress according to claim 5, characterized in that the foot portion is deflatable.

8. The mattress according to claim 7, characterized in that the portion of feet has a first length when the portion of the feet is deflated, the portion of the feet has a second length when the portion of the feet is inflated, and the second length is greater than the first length.

9. The mattress according to claim 8, characterized in that the foot portion is at a first height when the first foot portion is deflated, the foot portion is at a second height when the foot portion is inflated, and the foot portion is inflated; second height is greater than the first height.

10. The mattress according to claim 7, characterized in that the foot portion includes two bags which are inflated and deflated in two orthogonal directions to vary the height and length of the foot portion.

11. The mattress according to claim 5, characterized in that the foot portion and the seat portions are independently deflatable.

12. A mattress, characterized in that it comprises a surface for a patient, generally flat, having portions of head, buttocks, thighs, and feet, and the foot portion includes two bags which are inflated and deflated in two orthogonal directions to vary the height and length of the foot portion, the foot portion has a first length when deflated and a second length when inflated, and the second length is greater than the first length.

13. The mattress according to claim 12, characterized in that the foot portion has a first height when the foot portion is deflated, the foot portion has a second height when the foot portion is inflated, and the second height is greater than the first height.

14. The mattress according to claim 12, characterized in that the portion of the buttocks is deflatable and the portion of feet and the portions of buttresses are deflatable independently.

15. A mattress for use on a patient care bed having a longitudinally extending patient support platform provided with longitudinally extending raised top or platform portions along its sides, the mattress is characterized because it comprises a longitudinally extending central body portion to be placed on the supporting platform and side portions to be placed on the upper platform or deck portions, the central body portion has a depth greater than the depth of the lateral portions , and an inflatable and deflatable foot supporting portion extending longitudinally from the central body portion to support the lower parts of a patient's legs and feet.

16. a mattress for use with a stepped platform having an upper deck or platform, a deck or lower platform coupled to the deck or upper platform by a platform side wall, so that the lower deck or platform is separated from the deck or platform To define a cavity of the stepped platform, the mattress is characterized in that it comprises: a lower mattress section having an upper surface, a lower surface, and a side wall, the lower mattress section being configured to be located within the cavity of the stepped platform with the lower surface of the lower mattress section engaging the lower deck or platform, the side wall of the lower mattress section is located adjacent to the side wall of the platform, and the upper surface of the mattress section bottom is generally aligned in a plane of the deck or pla upper form; and a second upper mattress section having an upper surface, a lower surface, and a side wall, the upper surface of the upper mattress section providing a supporting surface for the body, and the lower surface of the upper mattress section it engages the upper surface of the lower mattress section and engages the upper deck or platform.

17. The mattress according to claim 16, characterized in that the lower mattress section and the upper mattress section are separate sections.

18. The mattress according to claim 16, characterized in that the upper mattress section includes portions supporting the head, body, and feet, the lower mattress section extends only below the portions supporting the head and body of the section of upper mattress.

19. The mattress according to claim 18, characterized in that the portion supporting the feet of the upper mattress is deflatable.

20. The mattress according to claim 16, characterized in that the stepped platform moves between a bed position and a chair position, the upper mattress section includes a portion supporting the feet, which has a first length when the stepped platform is in the bed position and a second length when the stepped platform is in the chair position, the second length is shorter than the first length.

21. The mattress according to claim 20, characterized in that the second length is at least 40% smaller than the first length.

22. The apparatus according to claim 16, characterized in that the lower mattress section has a thickness which is greater than a thickness of the upper mattress section.

23. A body-supporting surface for use on an articulated platform that moves between a bed position and a chair position, the support surface comprises a mattress having portions supporting the head, body, and feet, the portion that supports the feet has a first length when the platform is in the bed position and a second length when the platform is in the chair position, the second length is shorter than the first length, so that the portion supporting the feet of the mattress retracts when the platform moves towards the chair position, the mattress has a first thickness in the portions supporting the head and body and a second thickness in the portion supporting the feet, the second thickness is less than first thickness.

24. A surface for supporting the body for use on an articulated platform that moves between a bed position and a chair position, the support surface comprises a mattress having portions supporting the head, body, and feet, the supporting portion the feet have a first length when the platform is in the bed position and a second length when the platform is in the chair position, the second length is shorter than the first length, so that the portion supporting the legs Mattress feet retracts when the platform moves towards the chair position, the portions supporting the mattress' head and body have a first width and the portion supporting the feet has a second width, the second width is less than the first width.

25. A surface for supporting the body for use on an articulated platform that moves between a bed position and a chair position, the support surface comprises a mattress having portions supporting the head, body, and feet, the supporting portion the feet have a first length when the platform is in the bed position and a second length when the platform is in the chair position, the second length is shorter than the first length, so that the portion supporting the legs Mattress feet retracts when the platform moves towards the chair position, the second length is at least 40% smaller than the first length.

26. A surface for supporting the body for use on an articulated platform that moves between a bed position and a chair position, the support surface comprises a mattress having portions supporting the head, body, and feet, the supporting portion the feet have a first length when the platform is in the bed position and a second length when the platform is in the chair position, the second length is shorter than the first length, so that the portion supporting the legs mattress feet retracts when the platform moves towards the chair position, the portion supporting the feet includes two bags which are inflated and deflated in two orthogonal directions to vary the height and length of the portion supporting the feet.