Abstract:
The present invention provides a method and system for customization of flow characteristics of a support using permanent and controlled evacuation of interstitial gas during the manufacturing process. The flow characteristics can be customized to provide a stiffer or less stiff support by a comparative degree. The flow characteristics can be permanently changed. The support includes a bladder filled with a fluidized particulate material. The medium of the fluidized particulate material includes interstitial spaces. A predetermined amount of gas can be removed to provide a support having a desired specific support characteristic.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application No. 61/495,078, filed Jun. 9, 2011, the entirety of which is hereby incorporated by reference into this application. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Positioners, pressure relief devices, offloading devices and supports for body parts are known. For example, pillows or pads have been used for support of body parts. The supports have typically been formed of foam, gel or polyfill. Positioning aids have been described for restraining or immobilizing a part of the body of a medical patient. U.S. Pat. No. 3,764,404 describes a positioning aid. Polystyrene beads are confined within a bag. A self-closing valve communicating with the interior of the bag is used for evacuating air therefrom. After the bag is conformed to a portion of a patient&#39;s body, the positioning aid is evacuated and the aid becomes rigid with no flow characteristics of the material. 
         [0003]    It is desirable to provide a support having no memory or substantially no memory to enable the support to maintain contour to a body part. It is also desirable to provide a method and system for changing flow characteristics of a support, such as body part support and in particular, to a custom fitting limb or body part support. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention provides a method and system for customization of flow characteristics of a support using permanent and controlled evacuation of interstitial gas during the manufacturing process. For example, the gas can be air, helium, hydrogen or nitrogen. The flow characteristics can be customized to provide a stiffer or less stiff support by a comparative degree. For example, a bladder with reduced flow characteristics can be used in an operating room and a bladder with maximum flow characteristics could be used in an ICU. The flow characteristics can be permanently changed. 
         [0005]    The support includes a bladder filled with a fluidized particulate material. The medium of the fluidized particulate material includes interstitial spaces. The interstitial spaces can be formed by separation of the particulate material which is determined by shapes and sizes of particulate material. In one embodiment, the interstitial gas that is removed can be from within beads of the fluidized particulate material. In one embodiment, the particulate material refers to a compound or composition which can be sculpted and retain its shape and has no memory or substantially no memory. The no memory or substantially no memory feature enables the bladder to increase in height and simultaneously maintain support and three-dimensional micro-contouring to a body part. As the deflation occurs, the flow characteristic of the particulate material is changed. 
         [0006]    A predetermined amount of gas can be removed to provide a support having a specific support characteristic. The present invention provides that an amount of gas of about 500 millibars, preferably about 350 millibars to about 5 millibars to zero can be evacuated and the support will still provide fluid flow characteristics. In the present invention, a combination of a fill weight of the material within the support and the amount of gas removed can be used to control the flow characteristics of the material within the support. In one embodiment, substantially all gas is withdrawn from other fluidized particulate material, for example, to a pressure below about 5 millibars. In theory, flow characteristics can be brought below about 5 millibars but would render product non-functional because it would severely limit flow capabilities in most but not all particulate mediums. 
         [0007]    The support can be used as a pillow or as a pad to support any body extremity. For example, the support can be sized to fit and conform around a limb, such as an arm or leg or a portion thereof, foot, heel, finger, toe, torso, occiput, face or neck. 
         [0008]    The invention will be more fully described by reference to the following drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a schematic diagram of a bladder filled with a composition. 
           [0010]      FIG. 2  is a schematic diagram of a bladder being weighed. 
           [0011]      FIG. 3  is a schematic diagram of bladder placement on a vacuum and sealing machine. 
           [0012]      FIG. 4  is a schematic diagram of bladders on a vacuum and sealing machine. 
           [0013]      FIG. 5  is a schematic diagram of the bladder after removing air. 
           [0014]      FIG. 6  is a schematic diagram of a bladder after smoothing and trimming. 
           [0015]      FIG. 7A  is a schematic diagram of the composition of the present invention including interstitial spacing. 
           [0016]      FIG. 7B  is a schematic diagram of the composition of the present invention including interstitial spacing which is less than the interstitial spacing shown in  FIG. 7A . 
           [0017]      FIG. 7C  is a schematic diagram of the composition of the present invention including interstitial spacing which is less than the interstitial spacing shown in  FIG. 7B . 
           [0018]      FIG. 8  is a schematic diagram of a system including a plurality of bladders filled with the composition with each of the layers including a predetermined permanent flow characteristic. 
           [0019]      FIG. 9  is a schematic diagram of a system including a plurality of bladders filled with the composition with each of the layers including a predetermined permanent flow characteristic. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Reference will now be made in greater detail to a preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings and the description to refer to the same or like parts. 
         [0021]      FIG. 1  illustrates a step in a method for changing flow characteristics of a support in accordance with the teachings of the present invention in which bladder  11  is filled with composition  12  which can retain its shape after sculpting which is controlled by evacuation of gas from composition  12 . Composition  12  can be a particulate material including interstitial spaces between the particles. The amount of gas that is evacuated can depend on the size of the particles of the composition, wetness of the particles, dryness of the particles, amount of lubricant, hardness of the particle and the coefficient of the friction of the particles. Alternatively, composition  12  can include an encapsulated phase change material. For example, the phase change material can be encapsulated in a shell. 
         [0022]    In a subsequent step, bladder  11  is weighed on scale  20 , as shown in  FIG. 2 . In a subsequent step, bladder  11  is placed on conveyor  30  of vacuum and sealing machine  40 , as shown in  FIGS. 3 and 4 . Vacuum and sealing machine  40  removes a predetermined amount gas from composition  12  for creating a predetermined flow characteristic to composition  12  within bladder  11 . An example vacuum can sealing machine is manufactured by Multi-Vac machine that receives and puts pack in air at a desired level. For example, the gas can be air, helium, hydrogen or nitrogen. For example, if a greater amount of gas is removed, the composition will have a reduced flow characteristic. The amount of gas evacuated from the bladder determines permanent flow characteristics of the bladder. In a preferred embodiment, an amount of gas of about 500 millibars to about 5 millibars, preferably about 350 millibars to about 5 millibars or to zero millibars can be evacuated and the support will still provide fluid particulate flow characteristics. 
         [0023]      FIG. 5  illustrates bladder  11  after bladder  11  has been sealed and vacuumed before excess trim  50  is removed from bladder  11 . Bladder  11  has a wrinkled appearance indicating that gas has been removed and composition  12  within bladder  11  has predetermined permanent flow characteristics.  FIG. 6  illustrates support  60  comprising bladder  11  which has been trimmed to remove trim. Bladder  11  is smoothed to level composition  12  within bladder  11  and to check for leaks in seals of bladder  11 . Bladder  11  moves with composition  12  during contouring of bladder  11 . 
         [0024]    Support  60  is formed to have a predetermined permanent flow characteristic. Support  60  can be formed to fit around any body extremity. For example, support  60  can be sized to fit around a limb, such as an arm or leg or a portion thereof, finger, toe, torso, occiput, face or neck for providing simultaneous support characteristics and three-dimensional contouring characteristics. 
         [0025]      FIGS. 7A-7C  illustrate composition  12  including particles  14  and interstitial spacing  13 . Gas  15  can be present in spacing  13 . For example, gas  15  can be air, helium, hydrogen, or nitrogen.  FIG. 7A  illustrates composition  12  having greater interstitial spacing  13  than shown in  FIG. 7B .  FIG. 7B  illustrates composition  12  having greater interstitial spacing  13  than shown in  FIG. 7C . Accordingly, composition  12  shown in  FIG. 7A  will have the greatest flow characteristics and composition  12  shown in  FIG. 7C  will have the least flow characteristics. It will be appreciated that that in an alternative embodiment, composition  12  can be a porous foam substance including pockets of interstitial gas. In one embodiment, composition  12  can be a polyurethane foam. The polyurethane foam can be open or closed cell and cut into small shapes such as spheres or blocks. For example, a sphere of polyurethane foam can have a size of 2 inches in diameter. For example, a block of polyurethane foam can be a 1×1×1 inch block. 
         [0026]    In one embodiment, composition  12  can include a compound or composition which can be sculpted and retain its shape and has no memory or substantially no memory. The no memory or substantially no memory feature enables bladder  11  to mold in order to increase in height and maintain support of a body part. Composition  12  can be made of a viscosity that will allow it to contour but not collapse under the weight of the body part. In one embodiment, composition  12  can be formed of a mixture of microspheres and lubricant. The microspheres can include hollow or gas-filled structural bubbles (typically of glass or plastic) with an average diameter of less than 200 microns. The composition flows and stresses in response to a deforming pressure exerted on it and the composition ceases to flow and stresses when the deforming pressure is terminated. For example, composition  12  can be formed of a product referenced to as Floam™. A flowable compound comprising lubricated microspheres, including the compound itself, formulations for making the compound, methods for making the compound, products made from the compound and methods for making products from the compound as defined by U.S. Pat. Nos. 5,421,874, 5,549,743, 5,626,657, 6,020,055, 6,197,099, and 8,171,585, each of which is hereby incorporated by reference into this application. 
         [0027]    Bladder  11  can be formed of any air tight flexible plastic, such as urethane. Upon removal of residual gas  15  from composition  12 , bladder  11  flows concurrent with the flow of composition  12  such that bladder  11  moves with movement of composition  12 . Bladder  11  provides micro-contouring because composition  12  can respond three-dimensionally. 
         [0028]    In one embodiment, thermo-regulating material  16  is associated with composition  12 . An example material for thermo-regulating material  16  is manufactured by Outlast Technologies as fibers, fabrics, and foams comprising micro-encapsulated phase changing materials referred to as Thermocules, which store and release heat as further described in U.S. Pat. Nos. 7,790,283, 7,666,502 and 7,579,078, hereby incorporated by reference into this application. In one embodiment, the phase change material is a particulate or a lubricant for a particulate. 
         [0029]    In one embodiment, a lubricant and/or binding agent  18  can be present in interstitial spaces  13 . For example, lubricant and/or binding agent  18  can be a particulate material having a lower coefficient of friction, such as a powder. Lubricant and/or binding agent  18  can also include a dry medium, moist medium or wet medium. In one embodiment, composition  12  can include beads, such as polyethylene or polystyrene beads, expanded cross linked polyethylene, polypropylene beads, foam beads, or beads made of a similar medium. The beads can be hard shelled or flexible. In one embodiment, the beads are porous and flexible and gas  15  can be evacuated from the beads. In one embodiment, hard or rigid beads can be mixed with flexible beads in which gas  15  can be evacuated from the flexible beads. In one embodiment, composition  12  includes closed cell beads and open cell beads, such as foam, and gas  15  is removed from the foam. The smaller the interstitial spaces, the more the particles will collide thereby making composition  12  stiffer. 
         [0030]    The fluidized particulate material forming composition  12  can be formed of a material that normally would not have fluid characteristics in which flow characteristics are provided based on the interstitial spaces formed within the fluidized particulate material. A fluidized particulate material can be formed by lubricating spherical particles, using powder spherical particles and/or reducing the coefficient of friction. The flow characteristics can be controlled, for example, by reducing interstitial gas  15  which reduces the flow of the fluidized particulate material reducing surface contact which reduces friction between particles of the fluidized particulate material and/or using hard and soft particles in the fluidized particulate material. 
         [0031]    In one embodiment, substantially all gas is withdrawn from the fluidized particulate material, for example, to a pressure below about 5 millibars. 
         [0032]    The shapes and sizes of the particles in composition  12  can be selected to achieve desired flow characteristics. In one embodiment, a larger particulate material, such as expandable polyethylene beads, is used in composition  12  to provide greater interstitial spaces between particles. In this embodiment, increased gas is evacuated in order to achieve similar flow characteristics for composition  12 , including smaller particles. The reduction of interstitial space by virtue of the addition of wet or dry lubricant will change the amount of air evacuation required to reduce the flow characteristic. 
         [0033]    In one embodiment, lubricant is formed as an emulsification of porous beads that partially fills interstitial spaces. In this embodiment, less gas is withdrawn from the interstitial spaces  13  due to the porosity of the porous beads. 
         [0034]      FIG. 8  illustrates an alternate embodiment including support  100  formed of a plurality of bladders  110   a - 110   b . Each of bladders  110   a - 110   b  is filled with composition  12  which can retain its shape after sculpting which is controlled by evacuation of gas from composition  12 . Composition  12  can be a particulate material including interstitial spaces  13  between particles  14 . An amount of gas can be evacuated independently in each of bladders  110   a - 110   b  to provide each of bladders  110   a - 110   b  with a desired predetermined flow characteristic. The amount of gas that is evacuated can depend on the size of the particles of the composition, wetness of the particles, dryness of the particles, amount of lubricant, hardness of the particle and the coefficient of the friction of the particles. In one embodiment, a different composition  12  is used in one or more of bladders  110   a - 110   b.    
         [0035]    Support  100  is formed to have predetermined permanent flow characteristics. In this embodiment, bladder  110   a  provides increased flow characteristics over bladder  110   b  which has reduced flow characteristics. Accordingly, bladder  110   a  provides less support than bladder  110   b . Composition  12  having greater interstitial spacing  13  is shown in bladder  110   a . Composition  12  having less interstitial spacing  13  is shown in bladder  110   b . Accordingly, composition  12  shown in bladder  110   a  will have the greatest flow characteristics and composition  12  shown in bladder  110   b  will have the least flow characteristics. For example, an amount of gas can be evacuated from bladder  110   a  to provide a pressure in the range of about 500 millibars to about 100 millibars. An amount of gas can be evacuated from bladder  110   b  to provide a pressure in the range of about 100 millibars to about 5 millibars. 
         [0036]      FIG. 9  illustrates an alternate embodiment including support  200  formed of a plurality of bladders  210   a - 210   n . Each of bladders  210   a - 210   n  is filled with composition  12  which can retain its shape after sculpting which is controlled by evacuation of gas from composition  12 . Composition  12  can be a particulate material including interstitial spaces  13  between particles  14 . An amount of gas can be evacuated independently in each of bladders  210   a - 210   n  to provide each of bladders  210   a - 210   n  with a desired predetermined flow characteristic. The amount of gas that is evacuated can depend on the size of the particles of the composition, wetness of the particles, dryness of the particles, amount of lubricant, hardness of the particle and the coefficient of the friction of the particles. In one embodiment, a different composition  12  is used in one or more of bladders  210   a - 210   n.    
         [0037]    Support  200  is formed to have predetermined permanent flow characteristics. In this embodiment, bladder  210   a  provides increased flow characteristics over bladder  210   b . Bladder  210   b  has increased flow characteristics over bladder  210   n . Accordingly, bladder  210   a  provides minimum or loose support. Bladder  210   b  provides medium support. Bladder  210   c  provides maximum or stiff support. Composition  12  having the greatest interstitial spacing  13  is shown in bladder  210   a . Composition  12  having reduced interstitial spacing  13  is shown in bladder  210   b . Composition  12  having the least interstitial spacing  13  is shown in bladder  210   n . Accordingly, composition  12  shown in bladder  210   a  will have the greatest flow characteristics. Composition  12  shown in bladder  210   b  will have flow characteristics less than the flow characteristics in bladder  210   a  and more than the flow characteristics in bladder  210   n . Composition  12  shown in bladder  210   n  will have the least flow characteristics. For example, an amount of gas can be evacuated from bladder  210   a  to provide a pressure in the range of about 500 millibars to about 100 millibars. An amount of gas can be evacuated from bladder  210   b  to provide a pressure in the range of about 100 millibars to about 25 millibars. An amount of gas can be evacuated from bladder  210   n  to provide a pressure in the range of about 25 millibars to about 5 millibars. 
         [0038]    It is to be understood that the above-described embodiments are illustrative of only a few of the many possible specific embodiments, which can represent applications of the principles of the invention. Numerous and varied other arrangements can be readily devised in accordance with these principles by those skilled in the art without departing from the spirit and scope of the invention.