MATTRESS HAVING THREE SEPARATE ADJUSTABLE PRESSURE RELIEF ZONES
A support having adjustable pressure relief zones comprising at least three pressure zones, each having an adjustable pressure relief valve operatively attached to each of the at least three pressure zones. There is at least one cell in a first zone having a first effective fluid volume and at least one cell in a second zone having a second effective fluid volume adjustable to greater than said first effective fluid volume. The greater effective fluid volume is associated with supporting a greater load associated with that said zone and the lower fluid volume is for greater responsiveness.
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The present invention is a continuation-in-part of application Ser. No. 09/295,139 filed Apr. 20, 1999, now U.S. Pat. No. 6,269,505 (issued Aug. 7, 2001) and application Ser. No. 11/056,686 filed Feb. 11, 2005. The contents of both applications are incorporated by reference in their entirety.
FIELD OF THE INVENTIONThe present invention relates generally to an adjustable inflatable cushioning device for body supports such as a mattress, sofa, or chair cushion having separate pressure zones.
BACKGROUND OF THE INVENTIONInflatable cushioning devices for use with body supports, such as a mattress, sofa, seat, or the like may included a plurality of air cells or bladders that are inflated to support a person. The air cells provide support to the person, and can be inflated to a desired pressure level to provide the person with a predetermined level of comfort and support.
Air cushion devices may require an external pump to inflate the air cells in the device. Alternatively, the air cushion devices are pre-inflated in the manufacturing plant and are shipped to a field location for use. A problem may develop when the atmospheric pressure at the inflation location is different from the atomospheric pressure at the field location where the device is used. For example, if the field location atmospheric pressure is lower than the atmospheric pressure at the inflation location, the air cells in the field will expand and become firmer.
SUMMARY OF THE INVENTIONA first embodiment of the invention is a support having adjustable pressure relief zones comprising: at least three pressure zones; an adjustable pressure relief valve operatively attached to each of the at least three pressure zones; at least one cell in a first zone having a first effective fluid volume; and at least one cell in a second zone having a second effective fluid volume adjustable to greater than said first effective fluid volume, wherein the greater effective fluid volume is associated with supporting a greater load associated with that said zone.
A second embodiment of the invention is a mattress comprising: a first pressure zone having a first cell volume; a second pressure zone having a second cell volume operatively positioned with respect to said first pressure zone; a third pressure zone having a third cell volume operatively positioned with respect to said second pressure zone; and a dial positioned on each of the pressure zones to adjust an individual zone pressure.
A third embodiment of the invention is a mattress comprising: a first zone having a first fluid volume; a second zone having a second fluid volume operatively positioned with respect to said first zone; a third zone having a third fluid volume operatively positioned with respect to said second zone; an adjustable pressure valve in each of said zones; a resilient border surrounding said zones; and a cover encompassing said border and said zones.
A forth embodiment of the invention is a support surface comprising: a first zone having a port on each cell, a conduit attached to said ports, said conduit operatively attached to an intake check valve and a pressure relief valve; a second zone having an intake check valve on each cell, and an exhaust check valve on each cell that is attached to a common exhaust manifold, said exhaust manifold operatively attached to a pressure relief valve, wherein the second zone is operatively positioned with respect to said first zone; a third zone having a port on each cell, a conduit attached to each said port, said conduit operatively attached to an intake check valve and a pressure relief valve, wherein the third zone is operatively positioned with respect to said second zone; a first fluid cell volume associated with at least one of said zones; and a second fluid cell volume associated with at least one of said zones, wherein said second fluid cell volume is greater than said first fluid volume and wherein second fluid volume supports a greater load per square inch of a surface of said zone.
A fifth embodiment of the invention is a support surface comprising: a first zone having a single port on each cell, a first conduit attached to said ports, said first conduit operatively attached to an intake check valve and a pressure relief valve; a second zone having an intake check valve on each cell, and a port on each cell that is attached to a second conduit, said second conduit operatively attached to a pressure relief valve, wherein the second zone is operatively positioned with respect to said first zone; a third zone having a single port on each cell, a third conduit attached to each said port, said conduit operatively attached to an intake check valve and a pressure relief valve, wherein the third zone is operatively positioned with respect to said second zone; and a conduit crossover check valve allowing one way flow from the third conduit to the second conduit, wherein crossover flow to the second conduit refills fluid cells if cell pressure is below a pressure relief set point of each of the pressure relief valves of the second and third conduit.
BRIEF DESCRIPTION OF THE DRAWINGSThe features of the present invention will best be understood from a detailed description of the invention and a preferred embodiment thereof selected for the purposes of illustration and shown in the accompanying drawings in which:
Although certain preferred embodiments of the present invention will be shown and described in detail, it should be understood that various changes and modifications may be made without departing from the scope of the appended claims. The scope of the present invention will in no way be limited to the number of constituting components, the materials thereof, the shapes thereof, the relative arrangement thereof, etc., and are disclosed simply as an example of the preferred embodiment. The features and advantages of the present invention are illustrated in detail in the accompanying drawings, wherein like reference numerals refer to like elements throughout the drawings. Although the drawings are intended to illustrate the present invention, the drawings are not necessarily drawn to scale.
The present invention may provide a cushioning device for a mattress, seat, sofa, or the like where support is obtained from a fluid such as atmospheric air. The cushioning device has few moving parts, is user controllable, requires minimal maintenance, and is easily repairable. The cushioning device of the present invention may include a support system apparatus, a sleeve apparatus, a jacket, a topper cushion, and an outer cover.
The support system apparatus may include at least three support cells for providing lifting support for a body and having different zones with individual response rates tailored to weight. Each support cell in a zone may include an envelope containing a volume of fluid to match the anticipated weight supported to tailor the reactivity of the zone. Application of an external load on an outer surface of the envelope causes the envelope to deform into a compressed form. The envelope includes a reforming element that is capable of providing a reforming force to the interior surface of the envelope, to return the envelope to its original unloaded form. The reforming element is preferably made from a resilient foam material; however, other resilient means can be used.
An intake valve and an exhaust valve also may be included in each support cell within the zones. The exhaust valve in each support cell may be connected to a pressure control system to control the firmness of each zone. The intake valve in each support cell may be connected to an intake control system or draw fluid directly from the atmosphere. Each intake valve may include an intake check valve allowing fluid to flow into the support cell, while preventing fluid from flowing out of the support cell. Each exhaust valve includes an exhaust check valve allowing fluid to flow out of the support cell, while preventing fluid from flowing into the support cell. The intake control system may be connected to a fluid supply reservoir. The exhaust control system may also be connected to a fluid exhaust reservoir. The fluid included in the supply and exhaust reservoirs may be air, however, any suitable fluid, e.g., water or nitrogen can be used. The fluid supply and exhaust reservoirs may comprise the same reservoir, and may comprise an ambient source of fluid such as atmospheric air.
In use, the weight of a body of a person, patient, or animal resting on the envelope deforms the envelope or cells in each zone. For illustration purposes, a patient will be used as an example of a body resting on the envelope. The pressure of the fluid within the envelope increases as the volume of the envelope decreases under deformation. As the pressure of the fluid increases, the fluid in the envelope flows out of the envelope through the exhaust valve and into the exhaust control system. The individual zones are tailored so that the lightest weight of a patient is coordinated with a fluid cell having the lowest volume for the quickest removal of excess fluids. Next, the fluid may flow from the exhaust control system into the fluid exhaust reservoir. Furthermore, as the envelope deforms to conform to the irregular shape of the patient, the area of the envelope supporting the load increases. Equilibrium may be achieved when the forces within the envelope, including the pressure of the fluid within the envelope multiplied by the area of the envelope supporting the load, plus the force provided by the reforming element equal the weight of the load.
A controllable pressure relief valve is included in each zone so that a maximum or minimum pressure level of the fluid within the envelope can be set and maintained. Different selected maximum pressure levels of the fluid in the separate zones allow the support cell to accommodate different weights or allow different degrees of conformation between the patient and the envelope surface. The maximum pressure level of the fluid may be set to ensure that the interface pressure under the entire contact surface of the patient is below the pressure that may cause soft tissue damage such as pressure sores to occur. The pressure relief valve may be a mechanical device such as unidirectional, spring-loaded ball check valve that allows instant release of the excess fluid when pressure is exceeded without the requirement of power. The release pressure of the mechanical pressure relief valve can be adjusted by raising or lowering the spring tension of the valve for example by moving the seat of the spring with respect to the ball to change the spring pre-load.
As the weight of the patient is removed from the support cell, the reforming element exerts an outward force on the interior surface of the envelope. As the envelope expands, a partial vacuum is created in the interior space of the envelope, causing fluid to be drawn back into the interior space of the envelope. The fluid may be drawn from the fluid supply reservoir or directly from the atmosphere into the intake control system, through the intake valve, and into the interior space of the envelope. The intake valve may include a one way intake check valve that permits fluid to re-enter the interior space of the envelope, while preventing fluid from exiting the interior space of the envelope.
The support cells included in the present invention may use atmospheric pressure as the pressure source for inflation. Therefore, when the fluid supply and exhaust reservoirs comprise atmospheric air, inflation can be accomplished without the need for expensive blowers, pumps or microprocessors as required by previously available “treatment products.” A plurality of support cells can be interconnected with the intake control system and the exhaust control system to create a support system apparatus. The support system apparatus may support a patient by providing self adjusting pressure management to the entire contact surface of the patient. The support system apparatus provides a low interface pressure under the entire surface of the patient being supported. For example, if the patient is lying on the support system apparatus, the support system apparatus ensures that the interface pressure under the entire contact surface of the patient is below the pressure that may cause soft tissue damage to occur.
The support system apparatus also has the ability to self-adjust every time a patient moves, or is repositioned on the support system apparatus. When the pressure distribution applied to the support system apparatus changes, the support cells within the support system apparatus automatically inflate or deflate as necessary, to maintain a low interface pressure under the entire patient.
Another embodiment of the current invention provides for separately controlled responsiveness of the support zones within the support system apparatus. Each support zone comprises at least one support cell. Each support cell includes at least one intake valve and at least one exhaust valve. The intake valve for each support cell in each support zone is connected to the intake control system. The exhaust valves from each support cell in a single support zone may be connected to a single exhaust control system. Each support zone may have a separate exhaust control system. The intake control system may be connected to the fluid supply reservoir. The exhaust control system for each support zone may be connected to the fluid exhaust reservoir. Generally the pressure level in each support zone is set at a different level for comfort. The reactiveness of each support zone can be adjusted by modifying the amount of restriction adjacent the exhaust valve of each zone thus modifying the speed at which excess pressure is vented. For example, if the support system apparatus comprises a mattress in a bed, the upper, middle, and lower zones of the support system apparatus can be set to provide a different level of responsiveness for the upper, middle, and lower portions of the patient's body by adjusting how quickly the zones reach the set pressure. Thus for example, two identical mattresses could be set to the have the same maximum pressure in each zone, but one would have a fast response to movement and the other would have a slow or delayed response and would provide a firmer feel during patient movement even with the exact same pressure settings based solely on the setting of the adjustable restrictor placed in line before the pressure relief valve outlet and the zone.
The sleeve apparatus may includes a cell cover surrounding each support cell. For a plurality of support cells, each cell cover may be attached to an adjacent cell cover. The cell cover may allow the surface of the envelope of the support cell to slide freely along a first side of the cell cover, without transmitting this sliding movement to a second side of the cell cover. The second side of the cell cover may be the side on which a patient is lying. The movement of the support cell may not be transmitted to the patient, thereby preventing frictional or shear force abrasion damage to the skin of the patient. In the event that repair of a support cell becomes necessary, the sleeve apparatus allows each support cell to be easily removed and replaced.
The topper cover may provide further resilient torso support. The topper cover may be formed from a layered fiber filled material or other suitable material. The topper may include a resilient heel support unit to reduce pressures on the sensitive heel region of a patient. The topper cover may rest above the jacket, and may be covered by the outer cover. Alternatively, the topper cover may rest above the support system apparatus.
The outer cover provides a low friction and low shear surface further protecting the patient from frictional tissue damage. Additionally, the outer cover provides a waterproof and stain resistant surface. For medical uses the outer cover may be made from an anti-microbial type material.
The cushioning device of the present invention allows a user in the field to adjustably set the maximum pressure level in each support cell of the zone. When surrounded by atmospheric air, the support system apparatus is configured to be self-inflating, self-adjusting, and does not require expensive pumps and control systems as required by other related “treatment products.” Also, since there are fewer moving parts in the present invention, maintenance and repairs are simple and reasonable in cost compared to the complex related art.
The cushioning device of the present invention can be used in combination with any support device where self adjusting dynamic pressure support of the person or patient is required. For example, these support devices may be incorporated into a mattresses, sofas, seats, etc.
Referring to
The support system apparatus 12 includes at least one support cell 14 in each zone (1A, 1B, 1C, etc.) for providing lifting support for a patient 56 and each operatively include an intake valve 40 and an exhaust valve 42 are operatively attached either directly or indirectly to each support cell 14 within the zone. As illustrated in
The reforming elements 32A-C are preferably a resilient foam material, however, other resilient means can be used such as a coiled spring 500 (
An example of a support system apparatus 12 for a mattress includes a plurality of support cells 14A, 14B, 14C, and/or 14D as illustrated in
The intake control system 44 may be connected to a fluid supply reservoir 52 or directly to the atmosphere. The exhaust control system 46 may be connected to a variable restrictor (54A, 54B and 54C) or vented directly to the atmosphere to provided additional control of the reactivity of the zone to weight supported by the section. The variable restrictors (54A, 54B and 54C) may be used in addition to or in place of fluid cells having different fluid volumes 70 as the fluid volume once set is fixed, but the adjustable restrictors allow the patient to further fine tune the responsiveness of the zone. Generally, the fluid 36 included in the fluid supply reservoir 52 is air, however, any suitable fluid 36 (e.g. water or nitrogen) may be used. The fluid supply reservoir 52 may comprise an ambient source of fluid 36 such as atmospheric air.
As illustrated in
As illustrated in
As the weight of the patient 56 is removed from each support cell 14, the reforming element 32 (
Another embodiment of the present invention as illustrated in
Each exhaust control system 82, 84, and 86 includes a pressure relief valve 88, 90, and 92, respectively, which maintains the pressure of the fluid 36 in zones “A,” “B,” and “C” below a selected level. A rotatable knob 68 or other adjusting system may be included in each pressure relief valve 88, 90, and 92 allows a user to set the maximum pressure level of the fluid 36 in each zone “A,” “B,” and “C.” A heavier patient 56 may require or want a higher minimum pressure to support their weight more comfortably. Also a heavier person may want a firmer and less reactive zone to prevent a feeling of “squishiness” from rapid loss of fluid and may adjust the fluid reactivity valve 54 to have a smaller opening and therefore slower reaction to the movement of a patient 56.
The heel support system apparatus 240 includes a plurality of support cells 14, the end wall 29, a side wall 242, and a side wall 244. The heel support system 240 provides support for the heel area of a patient 56. The support cells 14 extend in a transverse direction on the mattress cushioning device 200 at the head and foot zones.
The optional jacket 18 may surround the torso support system apparatus 220 and the heel support system apparatus 240 and the head support system. The topper cushion 20 lies on top of the jacket 18 and provides further cushioning and comfort to the patient 56. The topper cushion 20 may be composed of any resilient material, for example, foam, down feathers, an inflatable air cushion, etc.
The support system apparatus 12 may include at least one self-inflating fluid cell, or reforming element, 14 such as an air spring, pod, or cartridge, having a spring bias, 14 for providing lifting support and discrete manipulation of a patient 56. As shown in
The application of an external load on the fluid cell 14 causes the fluid cell 14 to deform into a compressed form. The fluid cell 14 provides a reforming force which causes the fluid cell 14 to return to its original form when the external load is removed from the fluid cell 14. The fluid cell 14 may comprise a resilient material that can contain a fluid such as air, water or nitrogen. The fluid cell 14 may be formed from plastic or any elastomeric material that may be molded by convention processing techniques. The fluid cells 14 may be formed from foam or be constructed of a non-foam material.
A fluid cell 14 that contains air may be considered an air spring. The air spring 14 may be a cartridge that can be releasably attached, or quickly changed, by insertion and removal from a harnessing system 30. In this manner, if the air spring 14 needs to be changed, it can be done so with a friction slot or quick release mechanism.
The fluid cell 14 may have an exterior defined by folds along which the fluid cell collapses when loaded as described herein. For example, the fluid cell 14 could be a bellows 520 (
The air spring may have an external spring, but may also have an internal spring. The fluid cell 14 may include a coiled spring 500 (
In addition, the fluid cell may be restrained by an entrapment device 550 which restrains the expansion of at least one of the plurality of self-inflating fluid cells 14. An embodiment of an entrapment device is shown in
The firmness of the fluid cells may be controlled by adjusting the height of the fluid cell 14, the diameter of the fluid cell 14, the wall thickness of the fluid cell 14, the type of resin used to form the fluid cell 14, and the pitch or angle of the helix coupled with the OD and ID radius of the helix. In addition, the harnessing system 30, which allows control of the flow direction and volume, contributes to controlling the firmness of the fluid cells 14.
The embodiment shown in
The body support, or cushioning device 12 may includes a harnessing system 30 that controls the direction and flow volume of air into the self-inflating fluid cells 14 such that the pressure in one or a group of the plurality of self-inflating cells may be discretely controlled in the zone. The fluid cells 14 may be rotatable about a vertical axis 540 such that they may rotate in the casing 20 to allow them to be connected with the harnessing system 30 in various harnessing configurations. For example, the fluid cells 14 can be aligned such that the ports 40 are set at a 45 degree angle to the edge of the support apparatus 12. In addition, the harnessing system 30 may be releasably attached to the fluid cells 14 such that a plurality of harnessing configurations is possible. More specifically, the conduits, or connecting lines, 36 of the harnessing system 30, may be released from the ports 40 to which they are attached in a first harnessing configuration and reattached to another port on the same or another fluid cell 14 to create a second harnessing configuration. The harnessing system 30 allows for inflow of air to the fluid cell for reinflation speed and controllable and directional flow of air from the fluid cell 14.
Each self-inflating fluid cell may have an inlet port 40A and an exhaust port 40B as shown in
In addition,
An embodiment of the invention in
The support 10 may further comprise a reforming element 32, wherein the element 32 is a structure that is compressible under a load 56 and then returns to the original shape when the load 56 is removed. The reforming element 32 may have different shapes to create a different effective volume 70 in each of the at least three pressure zones to create the first effective fluid volume 70 and the second effective fluid volume 71. The support 10 may have fluid cells with different reactivities to loads 56 where the reforming element 32 is modified to have a different density 73 within each pressure zone 1, 2, or 3. The reforming element 32 can have fewer air holes 70 by either changing the material from for example foam to a material such a feathers or polyurethane fibers having a different amount of trapped air or the foam can have the density modified by increasing or decreasing the amount of air holes during processing of the foam reforming element 32.
Each pressure zone 1, 2, or 3 may have a pressure indicator 600, 601, 602 to allow the user to determine the proper P.S.I. setting for their comfort. The support 10 may further comprise a reforming element 32 positioned within each pressure zone 1, 2, or 3, wherein said first pressure zone 1 and said second pressure zone 2 has an equal cell volume and wherein the pressure zone supporting more weight is configured to have the reforming element 32 having a greater fluid displacement than the pressure zone 1 configured for less weight 56. The pressure zone 1 configured for supporting a lighter weight 56 has less fluid volume 70 and thus displaces the required fluid to support a patient 56 faster than a cell with more fluid volume 70.
The support 80 as displayed in
The support 80 may further comprise a first density reforming element 32D producing a first fluid volume 70 within one of the at least three pressure zones 1, 2 or 3 and a second density reforming element 32E producing a second fluid volume 71 within one of the at least three pressure zones 1, 2 or 3, wherein the second volume 71 is greater than the first volume 70 and wherein the greater volume is configured to support a greater weight. The greater volume may be produced by having more and larger air spaces in the foam reforming element and thus a greater fluid volume reforming element is of a lower density than the reforming element having a higher density.
The support 180 may further comprise a plurality of cells 14 in each pressure zone.
A mattress 300 comprising a first pressure zone 1 having a first cell volume 310, a second pressure zone 2 having a second cell volume 320, and a third pressure zone 3 having a third cell volume 330. The cell volumes 310, 320, 330 are configured to correspond to a weight of a patient 56 supported by that pressure zone 1, 2, or 3, wherein heavier weights correspond to greater fluid volume in that zone. The cell volumes 310, 320, 330 can be controlled by increasing or decreasing the open spaces 70 as shown in
The mattress 300 may have fluid cells 14 that further comprises an intake check valve 40 in each of the pressure zones 1, 2, or 3 or cells within the zone. The mattress 300 may also contain a support element 32 positioned within fluid cell 14 within each pressure zone 1, 2, or 3 to compensate for different weights 56 supported by each pressure zone 1, 2, or 3 to create a support surface for the mattress 300 that is responsive to the weight 56 supported by the pressure zones 1, 2, or 3. The mattress 300 in alternative may further comprise a cell reforming element 32, 500, 502, 520 positioned within the fluid cells 14.
A mattress 300 as shown in
A resilient border or side wall 28 may surround said pressure zones 1, 2, or 3 to cover any ducting and manifolds that are connected between the fluid cells 14 and the pressure valves 88, 90, 92. A cover or topper cushion 20 encompassing said border 28 and said pressure zones 1, 2, or 3. The mattress 300 may further comprise a plurality of cells 14 within the pressure zones 1, 2, or 3 as shown in
The mattress 10, as shown in
One of the difficulties of sleep is that as a person tosses and turns at night, their body pressure on the mattress or contact surface changes. Studies show that 85% of people sleep on their side. If such a person should shift during the night to their back, the surface area contacting the mattress would increase causing a decrease in pressure between the body and the mattress. However, the pressure on the heels would increase. Curvy people would tend to have less surface contact. The head may have a different pressure need than the body and heels. A persons head would normally be on a pillow which spreads out the surface contact area. A person sleeping on their back would have a greater pressure on their heels due to the small surface area.
An advantage of this system is that air pumps and compressor may be used but are not needed for adjusting the pressure in the zones. That is they are non-powered without pumps and function to maintain a constant pressure based on the cracking pressure of the dials on the pressure relief valves.
A pressure relief valve is a type of valve used to limit or control the pressure in a system. The pressure is relieved by allowing the pressurized fluid to flow from the valve out of the system. In this case when the pressure setting on the dial 68 is exceeded, the relief valve becomes the path of least resistance and the valve is forced open and only a portion of the fluid is diverted. Once the pressure reaches the re-sealing pressure set by the dial 68, the valve will re-close. An example is about 32 mmHg or 0.5 psi in the air cells regardless of the body weight.
The mattress 10 may further comprise a foam reforming element 32 may be positioned to substantially fill alternating cells 14 within each pressure zone 1, 2, or 3, such as shown in
The mattress zone 80 may further comprise a common intake manifold 30 on all cells 14 within each of the pressure zones 1, 2, or 3. There may be a common exhaust manifold on all cells 14 within each of the pressure zones 1, 2, or 3, wherein the exhaust manifold 88, 90, 92 in each zone is attached to the adjustable pressure valve 68 as shown in
A support surface 200 as shown in
Another embodiment of the support surface 500 that is self-inflating as shown in
The support surface 500 has second zone 502 having an intake check valve 540 on each cell 514B, and an exhaust port or check valve 560 on each cell 514B that is attached to a common exhaust manifold 582, said exhaust manifold 582 operatively attached to a pressure relief valve 588, wherein the second zone 502 is operatively positioned with respect to said first zone 501. As shown in
The support apparatus 500 has a third zone 503 having a port 560 on each cell 514 and a conduit 582 attached to each said port 560. The conduit 582 is operatively attached to an intake check valve 540 and a pressure relief valve 588 that are attached to the same or common conduit 582. The third zone 503 is operatively positioned with respect to said second zone 502. The third zone 503 is plumbed similarly to the first zone 501 in that the fluid 36 that leaves a compressed cell 514 enters an under-pressured cell 514 that aids in the process of reforming the attached fluid cell within the zone 503 more quickly and fluid above the set pressure level is vented from the conduit 582.
The support surface 500 has a first fluid cell volume 570 associated with at least one of said zones 501, 502, 503 and a second fluid cell volume 571 associated with at least one of said zones 501, 502, 503. The second fluid cell volume 571 is greater than said first fluid volume 570 and wherein second fluid volume supports a greater load per square inch of a surface of said zone. The greater fluid volume in the fluid cell 514 may be provided to support heavier loads such as the torso of a patient resting on the surface 500 more comfortably such as zone 502. The fluid volume is calculated in the amount of a fluid, such as air, present in the fluid cell 514 per square inch of the fluid cell to allow for size difference corrections. Generally the fluid cells 514 having the greatest load carrying capacity also have the greatest fluid volume, but all fluid cells may be identical and the release of the fluid 536 with a variable restrictor 554 may be used to tailor the fluid cell responsiveness to load. The support surface 500 may have a knob attached to each said pressure relief valve 588 that would allow the pressure relief setting to either be raised or lowered to accommodate either lighter or heavier than normal or average patients.
Another embodiment of the support surface 500 that is self-inflating is shown in
The support surface 500 has a second zone 502 having an intake check valve 540 directly attached onto each fluid cell 514, and a port 560 on each cell that is attached to a second conduit 581. The second conduit 581 is operatively attached to a pressure relief valve 588 that controls the maximum pressure within the connected fluid cells 514. The second zone 502 is operatively positioned with respect to said first zone 501 to form the support surface.
The fluid cells 514 in the second zone 502 are configured to support the heavier load of the torso of a patient by having two fluid refill entry points to quickly refill the fluid cell 514 that also may be configured to have a greater fluid volume 571 than fluid cells 514 in other zones. The intake check valve 540 allows one-directional flow into the cell 514 of fluid 536 from the atmosphere that is drawn by a partial vacuum produced by the reforming element such as a spring, foam or bellows when it returns the fluid cell 514 to a normal configuration after a load is removed. The port 560 allows two-way flow so that under load fluid exits the port 560 and when unloaded allows the port 560 receives pressurized fluid from a loaded cell 514 attached to the conduit 581 that is compressed by the patient. The pressure from the connected cell 514 is used to refill the cell 514 to the maximum set internal pressure, which may be greater than the internal force provided by the reforming element because of the use of a leveraged pumping action between the connected cells 514 within the zone 502.
The support surface 500 has a third zone 503 having a single port 560 on each cell 514 that allows two-directional flow of fluid 536 to the cell. A third conduit 583 is attached to each of the ports 560 allowing equalization of pressure within the zone 503 of all the fluid cells 514. The conduit 583 is operatively attached to an intake check valve 540 and a pressure relief valve 588. The third zone 503 is operatively positioned with respect to said second zone 502 that is positioned to form a patient surface.
A conduit crossover 584 with a crossover check valve 548 allows one-way flow from the third conduit 583 to the second conduit 582. The crossover conduit 584 allows crossover flow to the second conduit 582 and may refill the fluid cells 514 if their cell pressure is below a pressure relief set point of each of the pressure relief valves 588 of the second 581 and third conduit 583. The crossover conduit 584 allows one-way directional flow only from the third zone 503 that is configured for a lighter weight to the center zone 502 designed to support the heavier torso portion of the patient. The crossover conduit 584 forms a natural pumping action between zones that allows for a firmer mattress feel in the torso zone 502 by refilling fluid cells 514 quicker without resorting to pumps that may break, be noisy, fail during power loss or continuously consume power.
The support surface 500 may further comprise a reforming element 570 positioned in each fluid cell 514, wherein said reforming element 570 may be configured to have at least two different fluid cell volumes, wherein the at least two different fluid cell volumes 570, 571 of the zone is proportional to the weight the fluid cell 514 supports, wherein a greater weight (load) is supported by a greater fluid cell volume 571.
The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and many modifications and variations are possible in light of the above teaching. For example, the cushioning device of the present invention is suitable for providing self-inflating, self-adjusting, zoned pressure control, and alternating pressure support to any supported body. Also, the cushioning device of the present invention is suitable for any application where low interface pressure is required between the cushioning device and the surface of the body being supported. Such modifications and variations that may be apparent to a person skilled in the art are intended to be included within the scope of this invention as defined by the accompanying claims.
Claims
1. A support having adjustable pressure relief zones comprising:
- at least three pressure zones;
- an adjustable pressure relief valve operatively attached to each of the at least three pressure zones;
- at least one cell in a first zone having a first effective fluid volume; and
- at least one cell in a second zone having a second effective fluid volume adjustable to greater than said first effective fluid volume, wherein the greater effective fluid volume is associated with supporting a greater load associated with that said zone.
2. The support of claim 1 further comprising:
- a reforming element, wherein said element has a different volume in each of the at least three pressure zones to create the first effective fluid volume and the second effective fluid volumes.
3. The support of claim 1 wherein the reforming element has a different density within each pressure zone.
4. The support of claim 1 further comprising:
- a reforming element positioned within each pressure zone, wherein said first pressure and said second pressure zone has an equal cell volume and wherein the pressure zone supporting more weight is configured to have the reforming element having a greater fluid displacement than the pressure zone configured for less weight.
5. The support of claim 1 further comprising:
- an inlet valve on each of the pressure zones.
6. The support of claim 5 further comprising:
- a check valve associated within each of the inlet valves.
7. The support of claim 1 further comprising:
- a cover, wherein said cover surrounds the pressure zones.
8. The support of claim 1 further comprising:
- a first density reforming element producing a first volume within one of the at least three pressure zones; and
- a second density reforming element producing a second volume within one of the at least three pressure zones, wherein the second volume is greater than the first volume and wherein the greater volume is configured to support a greater weight.
9. The support of claim 1 further comprising:
- a plurality of cells in each pressure zone; and
- a plurality of reforming elements positioned within said plurality of cells, wherein said cells are interconnected and forms an average fluid volume in each pressure zone.
10. A mattress comprising:
- a first pressure zone having a first cell volume;
- a second pressure zone having a second cell volume operatively positioned with respect to said first pressure zone;
- a third pressure zone having a third cell volume operatively positioned with respect to said second pressure zone; and
- a dial positioned on each of the pressure zones to adjust an individual zone pressure.
11. The mattress of claim 10 further comprising:
- an intake check valve in each of the pressure zones.
12. The mattress of claim 10 further comprising:
- a pressure relief valve attached to the dial to control the maximum pressure.
13. The mattress of claim 10 further comprising:
- a support element positioned within the each pressure zone to compensate for different weights supported by each zone to create a support surface for the mattress that is responsive to the weight supported by the zone.
14. The mattress of claim 10 further comprising:
- a cell reforming element positioned within the fluid cells.
15. A mattress comprising:
- a first zone having a first fluid volume;
- a second zone having a second fluid volume operatively positioned with respect to said first zone;
- a third zone having a third fluid volume operatively positioned with respect to said second zone;
- an adjustable pressure valve in each of said zones;
- a resilient border surrounding said zones; and
- a cover encompassing said border and said zones.
16. The mattress of claim 15 further comprising:
- a plurality of cells within each of the zones;
- an intake manifold attached to each cell within each said zone; and
- an exhaust manifold attached to each cell within each said zone, wherein the exhaust manifold in each cell is attached to the adjustable pressure valve.
17. The mattress of claim 16 further comprising:
- a first plurality of cells within the first zone having a first size, wherein the first fluid volume is less than the second and third fluid volumes;
- a second plurality of cells within the second zone having a second size; and
- a third plurality of cells within the third zone having a third size, wherein the zone with the largest cells has the greatest fluid volume and bears the greatest weight.
18. The mattress of claim 17 further comprising:
- a reforming element positioned in alternating cells within each zone.
19. The mattress of claim 18 further comprising:
- a common intake manifold on all cells within each of the zones; and
- a common exhaust manifold on all cells within each of the zones, wherein the exhaust manifold in each zone is attached to the adjustable pressure valve.
20. A support surface comprising:
- a first zone having a port on each cell, a conduit attached to said ports, said conduit operatively attached to an intake check valve and a pressure relief valve;
- a second zone having an intake check valve on each cell, and an exhaust check valve on each cell that is attached to a common exhaust manifold, said exhaust manifold operatively attached to a pressure relief valve, wherein the second zone is operatively positioned with respect to said first zone;
- a third zone having a port on each cell, a conduit attached to each said port, said conduit operatively attached to an intake check valve and a pressure relief valve, wherein the third zone is operatively positioned with respect to said second zone;
- a first fluid cell volume associated with at least one of said zones; and
- a second fluid cell volume associated with at least one of said zones, wherein said second fluid cell volume is greater than said first fluid volume and wherein second fluid volume supports a greater load per square inch of a surface of said zone.
21. The support surface of claim 20 further comprising:
- a reforming element.
22. The support surface of claim 20 further comprising:
- a knob attached to each said pressure relied valve.
23. A support surface comprising:
- a first zone having a single port on each cell, a first conduit attached to said ports, said first conduit operatively attached to an intake check valve and a pressure relief valve;
- a second zone having an intake check valve on each cell, and a port on each cell that is attached to a second conduit, said second conduit operatively attached to a pressure relief valve, wherein the second zone is operatively positioned with respect to said first zone;
- a third zone having a single port on each cell, a third conduit attached to each said port, said conduit operatively attached to an intake check valve and a pressure relief valve, wherein the third zone is operatively positioned with respect to said second zone; and
- a conduit crossover check valve allowing one way flow from the third conduit to the second conduit, wherein crossover flow to the second conduit refills fluid cells if cell pressure is below a pressure relief set point of each of the pressure relief valves of the second and third conduit.
24. The support surface of claim 23 further comprising:
- a reforming element positioned in each fluid cell, wherein said reforming element is configured to have at least two different fluid cell volumes, wherein the at least two different fluid cell volumes of the zone is proportional to the weight the fluid cell supports, wherein a greater weight is supported by a greater fluid cell volume.
Type: Application
Filed: Aug 20, 2007
Publication Date: Feb 7, 2008
Applicant: M.P.L. LIMITED (Belize City)
Inventor: John Wilkinson (Lady Lake, FL)
Application Number: 11/841,047
International Classification: A47C 27/10 (20060101);