Patent Publication Number: US-6907633-B2

Title: Zoning of inflatable bladders

Description:
CLAIM OF PRIORITY 
     This application claims priority to U.S. provisional patent application Ser. No. 60/381,187, filed on May 16, 2002. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to inflatable cushions, mattresses and pads. In some embodiments, the invention can have alternately inflatable or expandable cells or bladders actuated by a pressure system. 
     BACKGROUND OF THE INVENTION 
     The present invention can be used with various types of bladders (or cells) used in inflatable cushions, mattresses or pads. In many cases these cushions, mattresses and pads are therapeutic and used by hospitals, businesses, and residences. 
     There are various types of cushions, mattresses or pads (collectively referred to as mattresses). Some of these variations are disclosed in commonly assigned U.S. Pat. No. 5,901,393 (Pepe et al.; title: Alternating Pressure Support Pad), and U.S. Pat. No. 6,079,070 (Flick; title: Disposable Inflatable Inclinable Cushion), which are hereby incorporated by reference. Obviously, these patents fail to disclose every type of inflatable mattresses but it does provide a representative sample. 
     In synopsis, every inflatable mattress has at least one bladder. That bladder can be made of polymeric materials having a top surface capable of receiving an object, a bottom surface that is opposite the top surface, and at least one side positioned between the top and bottom surfaces. In addition, every inflatable bladder is capable of receiving through an inlet a fluid, normally air or an aqueous solution, from a fluid source, normally a pump. From this fundamental understanding of inflatable bladders, the variations of bladders become evident. For example, some bladders (1) have the inlet of the fluid removed to become a self-contained device and (2) retain an inlet to receive fluid to become a dynamic device. 
     In the latter embodiment, the fluid exits the bladder through at least one outlet. In one version, the fluid exits the outlet through a conduit to return to the fluid source. In other versions the fluid exits the outlet through a conduit to a receiving unit, distinct from the fluid source. Another version has the surface of the bladder having a plurality of apertures designed to release at least a portion of the fluid toward the object lying on the inflatable bladder. Some bladders may have a CPR dump system to release the fluid expeditiously from the bladder. 
     Obviously, there may be alternative embodiments to these generic descriptions of bladders. In addition, the bladders may have alterations to (1) generate desired fluid flow patterns, (2) obtain desired mattress firmness and (3) allow the bladder adaptability for the mattress system. To obtain such results and others like it, the bladders have predetermined button welds, welds, and slits along welds. In addition, many of these alternative embodiments are embodied in numerous patent applications and patents, and product configurations. 
     As previously stated, numerous, if not all, inflatable bladders are constructed of some type of film material. The film material can be, for example, vinyl, polyethylene, or combinations thereof. When such film materials are used, the applicants have determined that the ability of the bladder to support loads for extended periods of time is greatly affected by creep of the material. 
     Creep occurs when an object, like a human, is placed on the mattress and displaces the air, at least immediately below the object, to the extremities of the bladder. Over time, creeping of the mattresses allows the object to bottom out on the inflatable mattress. Such results are undesirable and need to be minimized. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to diminish the material&#39;s creep problem found in inflatable bladders. This is accomplished by positioning an anti-creep zone within a bladder. The anti-creep zone is separated from the remainder of the bladder by a fluid barrier. The fluid barrier can have various embodiments that prevent and/or allow predetermined amounts of fluid into the anti-creep zone. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an isometric view of the present invention. 
         FIG. 2  illustrates a cross-sectional view of  FIG. 1  taken along the lines  2 — 2 . 
         FIGS. 3 and 4  illustrate alternative embodiments of FIG.  2 . 
         FIGS. 5-7  illustrate alternative embodiments of FIG.  1 . 
         FIGS. 8 and 9  illustrate alternative embodiments for providing a fluid to the anti-creep zone and the remainder of the bladder. 
         FIGS. 10   a-d  illustrates alternative embodiments to expel a fluid from the anti-creep zone. 
         FIG. 11  illustrates embodiments to expel a fluid from the remainder of the bladder. 
     
    
    
     DETAILED DESCRIPTION OF THE PRESENT INVENTION 
     The present invention is directed to a modification of bladders used in inflatable mattresses. Applicants admit that the bladder described in the Background of the Present Invention is a generic description of many bladders. This application, however, is not directed to bladders per se, but to what is within the bladders. Excluding fluids, welds, button welds and the like, the interior of a bladder is empty. It is empty because it is designed to have a fluid contained therein. Such designs, as described, above can result in creeping which in turn can result in bottoming out of the object on the mattress. Bottoming out and thus creeping are undesired. Therefore, applicants have modified the bladder design to diminish the possibility of such creeping and bottoming out. 
     The present invention is directed to inserting at least one anti-creep zone  100  into a bladder  102  as shown in FIG.  1 . At least one fluid barrier  104  separates the anti-creep zone  100  from the remainder of the bladder  106 . 
     The embodiment illustrated in  FIG. 2  clearly illustrates that the fluid barrier  104  extends from the top surface  110  of the bladder  102  that is designed to receive an object thereon, to the bottom surface  112  of the bladder  102 . In addition, the fluid barrier  104  can be of the same or different material as the bladder  102  so long as the material separates the fluid in the remainder of the bladder  106  from the fluid within the anti-creep zone  100 . As illustrated in  FIGS. 3 and 4 , the fluid barrier  104  may be interconnected to just the bottom surface  112  ( FIG. 4 ) or the top surface  110  (FIG.  3 ). The fluid barrier can be attached to the bladder  102  by welding, or any other conventional method to seal a polymeric material to another polymeric material. 
     Alternatively, the fluid barrier can be attached to at least one of the sides  114  positioned between the top surface  110  and the bottom surface  112 , as illustrated in FIG.  5 . In addition, the anti-creep zone  100 , or a combination of anti-creep zones  100 ,  100   a ,  100   b  can be positioned within the bladder  102 , as illustrated in  FIGS. 6 and 7 . 
       FIGS. 8 and 9  illustrate two embodiments in which fluid is provided to the bladder  102 . In each embodiment, a fluid source  134  provides a first fluid into an inlet  130 . The first fluid is then within at least the remainder of the bladder  106 . That embodiment is illustrated in both  FIGS. 8 and 9 . The difference between  FIGS. 8 and 9  resides in how the anti-creep zone receives its fluid. 
     As illustrated in  FIG. 8 , the anti-creep zone  100  can have its own exterior inlet  132  to receive a second fluid from a second fluid source  134   a . In reality, the fluid sources  134  and  134   a  can be the same or different, and provide the same or distinct fluids. 
     Alternatively,  FIG. 9  illustrates that the anti-creep zone has an inlet valve  150  that allows the first fluid from the remaining bladder  106  to enter the anti-creep zone. In a preferred embodiment, the inlet valve  150  will only allow the first fluid into the anti-creep zone until the first fluid reaches a predetermined pressure within the anti-creep zone. 
     Once the bladders  102  are filled to a desired pressure, the exterior inlets  130 ,  132  can be sealed off. That way, the bladders illustrated in  FIGS. 8 and 9  can become self-contained bladders. 
     Alternatively, the bladders illustrated in  FIGS. 8 and 9  can become dynamic bladders by retaining the exterior inlet ( FIG. 9 ) or inlets (FIG.  8 ). A dynamic bladder is one in which the fluid can at least exit the remainder of the bladder  106 .  FIGS. 10   a-d  illustrates different outlet designs for the anti-creep zone  100 . So there is no confusion, the embodiments illustrated in  FIGS. 10   a-d  are additional elements that are not illustrated in  FIGS. 8 and 9 . 
       FIG. 10   a  illustrates an outlet valve  170  that allows the fluid contained in the anti-creep zone  100  to exit into the remainder of the bladder  106 . Preferably, the outlet valve  170  will only allow the fluid to exit the anti-creep zone when the fluid within the anti-creep zone exceeds a predetermined pressure. Obviously, the predetermined pressure can be any value determined by the user and/or manufacturer by selecting certain outlet valves  170 . 
       FIG. 10   b  illustrates that the anti-creep zone  100  can alternatively have an exterior outlet  180 . The exterior outlet allows the fluid to exit the anti-creep zone into the fluid source  134 ,  134   a , or a reservoir  140 . 
       FIG. 10   c  illustrates interconnected anti-creep zones  100 ,  100   a ,  100   b . At least one valve  172  interconnects each zone  100 ,  100   a ,  100   b  to at least another zone, and possibly more. The valve  172  allows a fluid in the anti-creep zones  100 ,  100   a ,  100   b  to flow between different zones. In one embodiment, the valve  172  will only allow the fluid to flow to another zone if the fluid exceeds a predetermined pressure in the zone the fluid is leaving from. 
       FIG. 10   d  illustrates that the anti-creep zone  100  can have a plurality of apertures  160   a . If such apertures are utilized, the fluid should exit the anti-creep zone  100  through the top surface  110 . 
     Obviously, the embodiments illustrated in  FIGS. 10   a-d  can be incorporated into each anti-creep zone  100 . For example, the valves  172  and  170  can be used in a single anti-creep zone  100 . 
       FIG. 11  illustrates the possible outlet designs for the remainder of the bladder. One possible embodiment is to have an exterior outlet that exhausts the fluid to the fluid sources  134 ,  134   a , or reservoir  140 . Another embodiment has a plurality of apertures  160   b  positioned on the top surface  110 . That way, the fluid can exhaust and apply a fluid to the object positioned on the mattress. 
     It is desired that the anti-creep zone be positioned in the mattress in a position that receives the greatest weight of the object. For example, if the bladder was being used as a mattress, the anti-creep zone would be positioned preferably under at least the pelvic region of a human being, if the human was the object. In addition, there can be additional anti-creep zones positioned throughout the bladder, and mattress. These anti-creep zones can be individual zones or interconnected zones. 
     It has been determined that having at least one creep zone positioned in a bladder decreases the chances of the bladder creeping and the object bottoming out on the bladder. The more anti-creep zones used in a bladder and/or the proper positioning of the zones to receive the greatest weight of the object, diminishes the chances of creeping and bottoming out. 
     Even though they are not illustrated, the bladders illustrated in the figures can have button welds, welds and/or splits therein. These embodiments can be in the remainder of the bladder  106 , the anti-creep zone and/or the seal between the fluid barrier  104  and the bladder  102 . 
     The top surface can become the bottom surface by merely flipping the bladder over. Flipping the bladder is standard practice in the industry and does not deviate from the invention. 
     It should be understood that, while the invention has been described in detail herein, the invention can be embodied otherwise without departing from the principles thereof, and such other embodiments are meant to come within the scope of the present invention as defined by the appended claims.