Abstract:
A cellular reservoir flexible pressure vessel is formed as a series of closely packed tubes fitted into a pair of opposing end caps. The end caps have individual receptacles sized and shaped to receive the tube ends that are secured with adhesive or radio frequency welding. At least one end cap has a passageway for connection of the vessel. The vessel may be formed in a variety of useful shapes and the tubes may have various internal and external cross-sections. The end caps may be filled with sintactic foam with canals leading to the passageway. Microtubes through the syntactic foam may connect the tubes to the passageway. The vessel is further strengthened by overwrapping with high-strength braiding material, hoop winding or by overlayment with high-strength fabric. The vessel is further strengthened by coating with plastic resin. Apparatus and methods for forming the cellular reservoir flexible vessels are described.

Description:
FIELD OF INVENTION  
         [0001]    The invention pertains to devices for storing gases and fluids under pressure. More particularly, the invention relates to pressure vessels that are formed out of flexible materials and that can be made to conform to a variety of shapes.  
         BACKGROUND OF THE INVENTION  
         [0002]    Typically, pressure vessels capable of containing liquids or gases at significant pressures have involved fixed shape cylinders or spheres formed of high-strength metals such as steel or aluminum. Such pressure vessels, while successful for their designed applications, involve a number of problems. First, such metallic cylinders are relatively heavy compared to the gases or fluids that they contain. Second, pressure cylinders contain all of the gas or liquid in a single space. Should the vessel rupture, the entire vessel is destroyed, often with a violent explosion sending shards of metal in all directions. Third, metallic cylinders have a definite shape and cannot be adapted to fit readily in many space-constrained applications. The present invention involves a number of small cells of an elongated tubular shape linked to each other by collecting end caps. The result of this design is that the pressure vessel may be readily formed into a variety of useful shapes to accommodate special applications. A pressure vessel of this type can be lightweight, adaptable to a variety of spaces and unusual applications, and is inherently safer in rupture situations.  
           [0003]    Various designs have been developed using elongated tubular shaped vessels, most in the area of radiators and heat exchangers. U.S. Pat. No. 6,390,187 issued to Marechal et al. discloses a heat exchanger with flexible tubes. The tubes may be made from a plastic material and are designed to carry a heat-exchanging fluid capable of cooperating with an air stream circulating through the exchanger. The invention is intended to describe the method by which the tubes are maintained in parallel rows. The tubes are made from a plastic material and communicate by way of their extremities with two manifolds. The manifolds include collector plates equipped with apertures that thus form a means for holding the tubes in place. The tubes are arranged in rows that are parallel to one another by a distance corresponding to the tube thickness so that the various rows are adjacent in pairs of respective tubes of two consecutive pairs. The tubes generally exhibit a sinusoidal shape and thus aligned for expanding and contraction so that the tubes may utilize the flexible characteristics and maintain the integrity of the system.  
           [0004]    U.S. Pat. No. 4,450,902 issued to Bosne, is directed to a heat exchanger in particular for an atmospheric cooling tower. The exchanger utilizes synthetic plastic material for the tubes that has one fixed header while the remainder of the exchanger is mounted by suspension to allow for free expansion. A chamber has a heat exchanger with a series of tubes extending throughout the length of chamber. The exchanger comprises a battery of smooth tubes made of a synthetic material. The tubes of the heat exchanger are fixed to the support structure at one of the ends and is freely suspended by a suspension members to allow for expansion and contraction.  
           [0005]    U.S. Pat. No. 5,158,134, issued to Mongia et al., discloses a fully floating tube bundle. The exchanger comprises a plurality of fluid carrying tubes that is free floating with no direct contact between the end plates or center plate. Thus, the tubes are free to move with respect to the end plates and center plate as to eliminate damage by vibration and temperature changes.  
           [0006]    U.S. Pat. No. 4,114,683 issued to Verlinden describes a flexible tube type fluid-fluid heat exchanger. The exchanger comprises a plurality of flexible synthetic tubes extending in a curved path between a pair of headers. The tubes are connected to headers and are constructed of a flexible plastic material so they may easily conform to the curvature of the wall  11 .  
           [0007]    U.S. Pat. No. 5,651,474 issued to Callaghan et al is directed to cryogenic structures that are vessels made of a durable plastic material and are adapted to contain cryogenic materials such as fuel. The structures are made of a fiber network impregnated with a matrix of thermal set plastics and have three tank lobes of a composite plastic reinforced with fibers. The tank lobes may be filament-wound on a rotating mandrel while the fibers are pre-impregnated with resin. Another technique is to heat the tank skins allowing the pre-impregnated fiber layers to fuse together and then cool so as to set up a solid matrix that grips the fibers.  
           [0008]    While other variations exist, the above-described designs involving elongated tubular shaped vessels are typical of those encountered in the prior art. It is an objective of the present invention to provide a flexible pressure vessel that is capable of maintaining gasses or liquids at relatively high pressures. It is a further objective to provide this capability in a vessel that is light in weight and that presents a significantly reduced risk of injury in rupture situations. It is a still further objective of the invention to provide a pressure vessel that may be easily adapted to a variety of space constraints. It is yet a further objective to provide a pressure vessel that is durable, easily serviced, and that may be produced inexpensively.  
           [0009]    While some of the objectives of the present invention are disclosed in the prior art, none of the inventions found include all of the requirements identified.  
         SUMMARY OF THE INVENTION  
         [0010]    A cellular reservoir flexible pressure vessel providing the desired features may be constructed from the following components. A plurality of flexible tubes is provided. Each of the flexible tubes are formed of resilient material and have an outer surface, an inner surface, a first end and a second end.  
           [0011]    First and second end caps are provided. Each of the end caps have a receptacle for either of the first or second ends of each of the flexible tubes, a collecting reservoir, a surrounding outer rim and an outer perimeter perpendicular to the surrounding outer rim. At least one of the first and second end caps have a passageway connecting to the collecting reservoir for connection to either a passageway of another pressure vessel or a valve. Each of the receptacles has a surrounding wall, a base and an orifice penetrating the base and connects the receptacle to either the collecting reservoir or the passageway. The wall has an interior surface. The interior surface is sized and shaped to fit frictionally over the outer surface of one of the flexible tubes at either the first or second ends. The collecting reservoir has an outer surface and connects the base of each of the receptacles to a common space. The common space is either closed or connected to the passageway. The surrounding outer rim extends outwardly from the outer surface of the collecting reservoir for a first predetermined distance along the flexible tubes and serves to constrain the flexible tubes.  
           [0012]    Means are provided for securing the first and second end caps to the flexible tubes. A valving means is provided. The valving means is capable of controlling a flow of either a liquid or a gas through the passageway and is attached to a distal end of the passageway. When the flexible tubes are inserted into the receptacles of the end caps and secured thereto, a flexible pressure vessel will be formed capable of containing either a liquid or a gas at high pressure.  
           [0013]    In a variant of the invention, the means for securing the first and second end caps to the flexible tubes is selected from the group comprising: radio frequency welding, high-strength adhesive, mechanical fastening and sonic welding.  
           [0014]    In another variant of the invention, a protruding rim is provided. The protruding rim is located at the outer perimeter of the first and second end caps and upper and lower receiving notches located above and below the protruding rim. A reinforcing ring is provided. The reinforcing ring has an inner surface, an outer surface and is formed of high-strength material and is sized and shaped to fit tightly about the outer perimeter of the end cap. The reinforcing ring has an upper and lower projecting ribs and a central receiving notch located between the upper and lower projecting ribs. The projecting ribs are sized, shaped and located to fit the upper and lower receiving notches of the end cap. The central receiving notch is sized, shaped and located to fit the protruding rim of the end cap. The reinforcing ring has an aperture. The aperture extends from the inner surface to the outer surface and is sized, shaped and located to accommodate the passageway of the end cap. When the reinforcing ring is located about the outer perimeter of the first and second end caps, the pressure handling capacity of the pressure vessel is increased.  
           [0015]    In yet a further variant of the invention, a protruding rim is provided. The protruding rim is located at the outer perimeter of the first and second end caps and upper and lower receiving notches located above and below the protruding rim.  
           [0016]    Upper and lower reinforcing rings are provided. Each of the reinforcing rings have an inner surface, an outer surface and are formed of high-strength material and are sized and shaped to fit tightly in either of the upper and lower receiving notches. At least one of the reinforcing rings has an aperture. The aperture extends from the inner surface to the outer surface and is sized, shaped and located to accommodate the passageway connecting to the collecting reservoir. When the reinforcing rings are located about the outer perimeter of the first and second end caps, the pressure handling capacity of the pressure vessel is increased. Means are provided for fastening the upper reinforcing ring to the lower reinforcing ring.  
           [0017]    In still a further variant of the invention, a protruding rim is provided. The protruding rim is located at the outer perimeter of the first and second end caps. At least one groove located about the outer perimeter above the protruding rim is provided. At least one groove located about the outer perimeter below the protruding rim is provided. Upper and lower reinforcing rings are provided. Each of the reinforcing rings have an inner surface, an outer surface and are formed of high-strength material and are sized and shaped to fit tightly about the outer perimeter on either side of the protruding rim. The reinforcing rings have at least one rib located upon the inner surface thereof, the rib is sized, shaped and located to engage the groove. When the reinforcing rings are located about the outer perimeter of the first and second end caps, the pressure handling capacity of the pressure vessel is increased. Means are provided for fastening the upper reinforcing ring to the lower reinforcing ring.  
           [0018]    In yet a further variant of the invention a sintactic foam filler is provided. The foam filler is located within the collecting reservoir of at least one of the first and second end caps. The foam filler has a series of canals through it. Each of the canals connects the orifice of the receptacle to the passageway. An opening in the end cap is provided. The opening provides means for introduction of the sintactic foam into the end cap. A sealing plug is provided. The sealing plug is sized and shaped to fit sealably into the opening in the end cap. When the syntactic foam is introduced into the end cap, the pressure handling capacity of the pressure vessel is increased.  
           [0019]    In still a further variant of the invention, a sintactic foam filler is provided. The foam filler is located within the collecting reservoir of at least one of the first and second end caps. The foam is penetrated by a series of flexible microtubes. Each of the microtubes connects the orifice of the receptacle to the passageway. An opening in the end cap is provided. The opening provides means for introduction of the syntactic foam into the end cap. A sealing plug is provided. The sealing plug is sized and shaped to fit sealably into the opening in the end cap. When the microtubes are connected to the orifice of the receptacles in the end cap, the purity of either liquids or gasses stored in the pressure vessel is increased.  
           [0020]    In yet a further variant of the invention, an overwrapping of high-strength braiding material is provided. The braiding material extends over the flexible tubes and the first and second end caps. When the flexible pressure vessel is so overwrapped, its pressure-handling capability will be increased.  
           [0021]    In another variant, a plastic overcoating is provided. The overcoating further increases the pressure-handling capability of the pressure vessel.  
           [0022]    In still a further variant of the invention, a hoop winding with high-strength materials is provided. The hoop winding extends over the flexible tubes and the first and second end caps. When the flexible pressure vessel is so hoop wound, its pressure-handling capability will be increased.  
           [0023]    In another variant, a plastic overcoating is provided. The overcoating further increases the pressure-handling capability of the pressure vessel.  
           [0024]    In yet a further variant of the invention, a first flexible blanket is provided. The first blanket has an upper surface, a lower surface and is sized and shaped to cover the pressure vessel and extends outwardly beyond the outer edges thereof. The first blanket is fixedly attached at its lower surface to an upper surface of the pressure vessel. A second flexible blanket is provided. The second blanket has an upper surface, a lower surface and is sized and shaped to cover the pressure vessel and extends outwardly beyond the outer edges. The second blanket is fixedly attached at its upper surface to a lower surface of the pressure vessel. When the first and second flexible blankets are attached to the pressure vessel, the pressure handling capability of the pressure vessel will be increased.  
           [0025]    In another variant, heavy duty stitching is used to attach the first blanket to the second blanket. The stitching penetrates the first and second blankets between the upper and lower cell portions and serves to further reinforce and increase the pressure-handling capabilities of the pressure vessel. In still another variant, the heavy duty stitching is high pressure hoop and lock braiding.  
           [0026]    In still a further variant of the invention, the cross-sectional shape of the outer surface of the flexible tubing is selected from the group comprising: square, triangular, round, hexagonal, ovoid, octagonal and star shaped.  
           [0027]    In yet a further variant of the invention, the cross-sectional shape of the inner surface of the flexible tubing is selected from the group comprising: square, triangle, round, hexagonal, ovoid, octagonal, and star-shaped.  
           [0028]    In still a further variant of the invention, the cross-sectional shape of the flexible pressure vessel is selected from the group comprising: square, triangular, round, hexagonal, ovoid, octagonal, pillow shaped, saddle shaped, and a flattened mat shape.  
           [0029]    In yet a further variant of the invention, each of the receptacles are of a concave form selected from the group comprising: conical, dome-shaped, ellipsoid and stair-stepped. In a variant, the first and second ends of each of the flexible tubes are sized and shaped to fit sealably into the receptacles.  
           [0030]    In still a further variant of the invention, upper and lower reinforcing panels are provided. The reinforcing panels are formed of high-strength woven material and are shaped as a form to cover at least half of a surface area of the pressure vessel with extensions projecting from a perimeter of the form. The reinforcing panels are joined to the outer surface of the upper and lower cell portions of the hollow pressure cell, thereby increasing the pressure handling capability of the pressure cell.  
           [0031]    In a variant, the method of adhesion is selected from the group comprising: high-strength adhesive, sonic welding and RF welding.  
           [0032]    In another variant, the woven material is prepregnated with either adhesive or laminating material and subjected to heat and pressure.  
           [0033]    An apparatus for fabricating a cellular reservoir flexible pressure vessel may be constructed from the following components. A raw plastic storage and feeding unit is provided. The storage and feeding unit contains a supply of raw plastic. A multi-head extruder is provided. The extruder includes a heating facility and is in communication with the feeding unit. A cooling tank is provided. The cooling tank is located downstream from the extruder. A power puller is provided. The puller serves to pull a tubing bundle from the cooling tank. Core tubing forming dies are provided. The forming dies form the tubing bundle into a predetermined shape. A binder head is provided. The binder head has an attached binder tank containing liquid binder material. A binder applicator is provided. The binder applicator comprises a secondary forming die and serves to affix the binder material to the tubing bundle. A cutting unit is provided. The cutting unit comprises a laser calibration facility and serves to cut the tubing bundle to a predetermined length. A conveyer facility is provided. The conveyer facility comprises means for positioning a cut tubing bundle. A rotating head and ram is provided. The head comprises a glue head applicator. The glue head applicator attaches to a glue tank. A plurality of preformed end caps are provided. An automated end cap loader is provided. The end cap loader positions the plurality of end caps. An automated end cap installer attached to the automated end cap loader is provided. The installer serves to attach the end caps to the tubing bundle. A high-intensity UV lamp assembly is provided. The lamp assembly serves to cure the glue.  
           [0034]    In a variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, a plurality of reinforcing rings is provided. The reinforcing rings are formed of high-strength material. A reinforcing ring auto loader is provided. A swivel ram is provided. The ram comprises of a ring loading and placement head. The swivel ram is in cooperation with the ring auto loader and serves to press the reinforcing ring onto the pressure vessel.  
           [0035]    In another variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, either a gas or liquid supply tank is provided. An auto loader test head is provided. The test head is adaptable to fittings on the end caps. A cryogenic test unit in communication with the test head is provided. The test head and the test unit provides means for pressurizing the pressure vessel.  
           [0036]    In yet a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, a reinforcing blanket material is provided. A glue spraying mechanism is provided. The mechanism comprises of glue tanks, glue spray heads and glue for attaching the blanket material to the pressure vessel. A blanket material feed mechanism is provided. A press forming tool is provided. The tool is adapted to form the blanket material over the cut tubing bundle and the attached end caps. In a variant, a high-strength thread is provided. A stitching head is provided. The stitching head is adapted to sew the high-strength thread through the reinforcing blanket material.  
           [0037]    In still a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel includes a high-strength braiding material. A braider is provided. The braider is adapted to position and provide overwrapping of the pressure vessel with the braiding material. A binder spraying mechanism is provided. The spraying mechanism comprises of a binder tank, a binder spray head and binder material.  
           [0038]    In yet a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, a high-strength reinforcing ribbon is provided. An automated reinforcing ribbon winding machine is provided. The winding machine comprises of a reinforcing ribbon spool and an auto layout ribbon head. A binder spraying mechanism is provided. The spraying machine comprises of a binder tank, a binder spray head and binder material.  
           [0039]    In still a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, means are provided for pulling a series of high tensile strength core wires through orifices in receptacles in the end cap to a passageway in the end cap. Means are provided for injecting sintactic foam through an opening in the end cap. Means are provided for attaching a sealing plug to the opening. Means are provided for removing the core wires from the end cap. When the core wires are removed from the end cap, a series of canals will be formed in the sintactic foam connecting orifices in receptacles in the end cap to the passageway.  
           [0040]    In yet a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, means are provided for attaching a series of flexible microtubes to orifices in receptacles in the end cap to a passageway in the end cap. Means are provided for injecting sintactic foam through an opening in the end cap. Means are provided for attaching a sealing plug to the opening. Means are provided for removing the core wires from the end cap. When the microtubes are connected to the passageway, the pressure vessel will provide an ultra clean environment for either liquids or gasses.  
           [0041]    In still a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, means are provided for forming a concave receptacle having a shape selected from the group comprising: conical, dome-shaped, ellipsoid and stair-stepped. In a variant, means are provided for forming the first and second ends of each of the flexible tubes to fit sealably into the receptacles.  
           [0042]    In yet a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, means are provided for forming upper and lower reinforcing panels. The reinforcing panels are formed of high-strength woven material and are shaped as a form to cover at least half of a surface area of the pressure vessel with extensions projecting from a perimeter from the form. Means are provided for adhering the reinforcing panel to the outer surface of the upper and lower cell portions of the hollow pressure cell, thereby increasing the pressure handling capability of the pressure cell.  
           [0043]    In a variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, the method of adhesion is selected from the group comprising: high-strength adhesive, sonic welding and RF welding.  
           [0044]    In a final variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel, the woven material is prepregnated with either adhesive or laminating material and subjected to heat and pressure. 
       
    
    
     DESCRIPTION OF THE DRAWINGS  
       [0045]    [0045]FIG. 1 is a plan view of a first embodiment of the invention illustrating cellular reservoir cells, first and second end caps, a connecting passageways and a valve;  
         [0046]    [0046]FIG. 2 is a cross-sectional view of the FIG. 1 embodiment taken along the line  2 - 2 ;  
         [0047]    [0047]FIG. 2A is an end cross-sectional view of the FIG. 1 embodiment taken along the line  2 A- 2 A;  
         [0048]    [0048]FIG. 3 is an end view of the FIG. 1 embodiment taken along the line  3 - 3  illustrating a first embodiment of a reinforcing ring, an aperture in the ring and a cross-section of the ring in partial cutaway;  
         [0049]    [0049]FIG. 3A is a side elevational view of the FIG. 1 embodiment, illustrating a first embodiment of upper and lower reinforcing rings;  
         [0050]    [0050]FIG. 4 is a partial cross-sectional view of the FIG. 3A embodiment taken along the line  4 - 4 ;  
         [0051]    [0051]FIG. 5 is a partial cross-sectional view of the FIG. 3A embodiment illustrating a means for fastening the upper and lower reinforcing rings together;  
         [0052]    [0052]FIG. 6 is a partial cross-sectional view of a second embodiment of upper and lower reinforcing rings illustrating grooves and ribs for attaching the rings;  
         [0053]    [0053]FIG. 7 is a partial cross-sectional view of a third embodiment of upper and lower reinforcing rings illustrating grooves and ribs for attaching the rings and means for attaching the rings together;  
         [0054]    [0054]FIG. 8 is a cross-sectional view of an end cap illustrating means for introducing sintactic foam into the end cap and wires for forming canals through the foam;  
         [0055]    [0055]FIG. 9 is a cross-sectional view of an end cap illustrating microtubes connecting the receptacles to the passageway and a sealing plug for closing the end cap after introduction of the syntactic foam;  
         [0056]    [0056]FIG. 10 is a side elevational view of the FIG. 1 embodiment illustrating an overwrapping of high-strength braiding material;  
         [0057]    [0057]FIG. 11 is a side elevational view of the FIG. 1 embodiment illustrating hoop winding;  
         [0058]    [0058]FIG. 12 is a partial cross-sectional view of the FIG. 1 embodiment illustrating a plastic overcoating;  
         [0059]    [0059]FIG. 13 cross-sectional view of the FIG. 1 embodiment illustrating flexible blankets attached to the pressure vessel;  
         [0060]    [0060]FIG. 14 is a plan view of the FIG. 1 embodiment illustrating high-strength stitching of the flexible blankets;  
         [0061]    [0061]FIG. 15A is a cross-sectional view of a cellular reservoir tube having a hexagonal external cross-section;  
         [0062]    [0062]FIG. 15B is a cross-sectional view of a cellular reservoir tube having a square external cross-section;  
         [0063]    [0063]FIG. 15C is a cross-sectional view of a cellular reservoir tube having a equilateral triangular external cross-section;  
         [0064]    [0064]FIG. 15D is a cross-sectional view of a cellular reservoir tube having an oval external cross-section;  
         [0065]    [0065]FIG. 15E is a cross-sectional view of a cellular reservoir tube having a right triangular external cross-section;  
         [0066]    [0066]FIG. 15F is a cross-sectional view of a cellular reservoir tube having a round external cross-section;  
         [0067]    [0067]FIG. 15G is a cross-sectional view of a cellular reservoir tube having a octagonal external cross-section;  
         [0068]    [0068]FIG. 15H is a cross-sectional view of a cellular reservoir tube having a star-shaped external cross-section;  
         [0069]    [0069]FIG. 16A is a cross-sectional view of a cellular reservoir tube having a hexagonal internal cross-section;  
         [0070]    [0070]FIG. 16B is a cross-sectional view of a cellular reservoir tube having a square internal cross-section;  
         [0071]    [0071]FIG. 16C is a cross-sectional view of a cellular reservoir tube having a equilateral tringular internal cross-section;  
         [0072]    [0072]FIG. 16D is a cross-sectional view of a cellular reservoir tube having an oval internal cross-section;  
         [0073]    [0073]FIG. 16E is a cross-sectional view of a cellular reservoir tube having a right triangular internal cross-section;  
         [0074]    [0074]FIG. 16F is a cross-sectional view of a cellular reservoir tube having a round internal cross-section;  
         [0075]    [0075]FIG. 16G is a cross-sectional view of a cellular reservoir tube having a octagonal internal cross-section;  
         [0076]    [0076]FIG. 16H is a cross-sectional view of a cellular reservoir tube having a star-shaped internal cross-section;  
         [0077]    [0077]FIG. 17A is a cross-sectional view of a cellular reservoir flexible pressure vessel having a hexagonal shape;  
         [0078]    [0078]FIG. 17B is a cross-sectional view of a cellular reservoir flexible pressure vessel having a square shape;  
         [0079]    [0079]FIG. 17C is a cross-sectional view of a cellular reservoir flexible pressure vessel having an equilateral triangular shape;  
         [0080]    [0080]FIG. 17D is a cross-sectional view of a cellular reservoir flexible pressure vessel having an oval shape;  
         [0081]    [0081]FIG. 17E is a cross-sectional view of a cellular reservoir flexible pressure vessel having an airfoil shape;  
         [0082]    [0082]FIG. 17F is a cross-sectional view of a cellular reservoir flexible pressure vessel having a right triangular shape;  
         [0083]    [0083]FIG. 17G is a cross-sectional view of a cellular reservoir flexible pressure vessel having a round shape;  
         [0084]    [0084]FIG. 17H is a cross-sectional view of a cellular reservoir flexible pressure vessel having a octagonal shape;  
         [0085]    [0085]FIG. 17I is a cross-sectional view of a cellular reservoir flexible pressure vessel having a saddle shape;  
         [0086]    [0086]FIG. 17J is a cross-sectional view of a cellular reservoir flexible pressure vessel having a flat mat shape;  
         [0087]    [0087]FIG. 18A is a cross-sectional view of a receptacle and fitting square-shaped flexible tube end;  
         [0088]    [0088]FIG. 18B is a cross-sectional view of a receptacle and fitting cone-shaped flexible tube end;  
         [0089]    [0089]FIG. 18C is a cross-sectional view of a receptacle and fitting hemi-spherical-shaped flexible tube end;  
         [0090]    [0090]FIG. 18D is a cross-sectional view of a receptacle and fitting step-shaped flexible tube end;  
         [0091]    [0091]FIG. 18E is a cross-sectional view of a receptacle and fitting bullet-shaped flexible tube end;  
         [0092]    [0092]FIG. 19 is a side elevational view of the FIG. 1 embodiment enclosed in upper and lower reinforcing panels;  
         [0093]    [0093]FIG. 20 is a plan view of the FIG. 1 embodiment on upper and lower reinforcing panels prior to attachment;  
         [0094]    [0094]FIG. 21 is a side elevational view of an apparatus for fabricating flexible tubes for a cellular reservoir flexible pressure vessel;  
         [0095]    [0095]FIG. 22 is a side elevational view of an apparatus for cutting the tubes to length and attaching the end caps;  
         [0096]    [0096]FIG. 23 is a side elevational view of an apparatus for curing the adhesive for the flexible tubes and attaching the reinforcing rings;  
         [0097]    [0097]FIG. 24 is a side elevational view of apparatus for filling the vessel with cryogenic liquid or gas, attaching high-strength blanket material and stitching high-strength thread through the reinforcing blanket material;  
         [0098]    [0098]FIG. 25 is a side elevational view of an apparatus for overwrapping of the pressure vessel with high-strength braiding material;  
         [0099]    [0099]FIG. 26 is a side elevational view of an apparatus for hoop winding reinforcing ribbon onto the pressure vessel;  
         [0100]    [0100]FIG. 27 is a side cross-sectional view of an apparatus for pulling wires into the end cap prior to injection of syntactic foam to leave canals;  
         [0101]    [0101]FIG. 28 is a side cross-sectional view of an apparatus for pulling microtubes into the end cap prior to injection of syntactic foam;  
         [0102]    [0102]FIG. 29 is a detailed side cross-sectional view of an apparatus for forming a concave receptacle having a dome shape;  
         [0103]    [0103]FIG. 29A is a side cross-sectional view of an apparatus for a series of concave receptacles having a dome shape;  
         [0104]    [0104]FIG. 30 is a side cross-sectional view of an apparatus for forming the first and second ends of each of said flexible tubes to fit sealably into said receptacles;  
         [0105]    [0105]FIG. 31 is a perspective view of an apparatus for forming reinforcing panels; and  
         [0106]    [0106]FIG. 32 is a perspective view of an apparatus for applying adhesive to a reinforcing panel. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0107]    (1) A cellular reservoir flexible pressure vessel  10  providing the desired features, as shown in FIG. 1, FIG. 2 and FIG. 2A, may be constructed from the following components. A plurality of flexible tubes  15  is provided. Each of the flexible tubes  15  are formed of resilient material  20  and has an outer surface  25 , an inner surface  30 , a first end  35  and a second end  40 .  
         [0108]    First  45  and second  50  end caps are provided. Each of the end caps  45 ,  50  has a receptacle  55  for either of the first  35  or second  40  ends of each of the flexible tubes  15 , a collecting reservoir  70 , a surrounding outer rim  75  and an outer perimeter  80  perpendicular to the surrounding outer rim  75 . At least one of the first  45  and second  50  end caps has a passageway  85  connecting to the collecting reservoir  70  for connection to either a passageway  85  of another pressure vessel  10  or a valve  90 . Each of the receptacles  55  has a surrounding wall  95 , a base  100  and an orifice  105  penetrating the base  100 . The orifice  105  connects the receptacle  55  to either the collecting reservoir  70  or the passageway  85 . The wall  95  has an interior surface  110 . The interior surface  110  is sized and shaped to fit frictionally over the outer surface  25  of one of the flexible tubes  15  at either the first  35  or second  40  ends. The collecting reservoir  70  has an outer surface  115  and connects the base  100  of each of the receptacles  55  to a common space  120 . The common space  120  is either closed or connected to the passageway  85 . The surrounding outer rim  75  extends outwardly from the outer surface  115  of the collecting reservoir  70  for a first predetermined distance  125  along the flexible tubes  15  and serves to constrain the flexible tubes  15 .  
         [0109]    Means  130  are provided for securing the first  45  and second  50  end caps to the flexible tubes  15 . A valving means  135  is provided. The valving means  135  is capable of controlling a flow of either a liquid or a gas through the passageway  85  and is attached to a distal end  150  of the passageway  85 . When the flexible tubes  15  are inserted into the receptacles  55  of the end caps  45 ,  50  and secured thereto, a flexible pressure vessel  10  will be formed capable of containing either a liquid or a gas at high pressure.  
         [0110]    (2) In a variant of the invention, the means for securing the first  45  and second  50  end caps to the flexible tubes  15  is selected from the group comprising: radio frequency welding, high-strength adhesive, mechanical fastening and sonic welding.  
         [0111]    (3) In another variant of the invention, as shown in FIG. 3, a protruding rim  180  is provided. The protruding rim  180  is located at the outer perimeter  80  of the first  45  and second  50  end caps and upper  185  and lower  190  receiving notches located above and below the protruding rim  180 . A reinforcing ring  195  is provided. The reinforcing ring  195  has an inner surface  200 , an outer surface  205  and is formed of high-strength material  206 . The reinforcing ring  195  is sized and shaped to fit tightly about the outer perimeter  80  of the end caps  45 ,  50 . The reinforcing ring  195  has an upper  210  and lower  215  projecting ribs and a central receiving notch  220  located between the upper  210  and lower  215  projecting ribs. The projecting ribs  210 ,  215  are sized, shaped and located to fit the upper  185  and lower  190  receiving notches of the end caps  45 ,  50 . The central receiving notch  220  is sized, shaped and located to fit the protruding rim  180  of the end caps  45 ,  50 . The reinforcing ring  195  has an aperture  225 . The aperture  225  extends from the inner surface  200  to the outer surface  205  and is sized, shaped and located to accommodate the passageway  85  of the end caps  45 ,  50 . When the reinforcing ring  195  is located about the outer perimeter  80  of the first  45  and second  50  end caps, the pressure handling capacity of the pressure vessel  10  is increased.  
         [0112]    (4) In yet a further variant of the invention, as shown in FIG. 3A and FIG. 4, a protruding rim  180  is provided. The protruding rim  180  is located at the outer perimeter  80  of the first  45  and second  50  end caps. Upper  185  and lower  190  receiving notches are provided. The upper  185  and lower  190  receiving notches are located above and below the protruding rim  180 .  
         [0113]    Upper  230  and lower  235  reinforcing rings are provided. Each of the reinforcing rings  230 ,  235  has an inner surface  240 , an outer surface  245  and is formed of high-strength material  246 . The upper  230  and lower  235  reinforcing rings are sized and shaped to fit tightly in either of the upper  185  and lower  190  receiving notches. At least one of the reinforcing rings  230 ,  235  has an aperture  250 . The aperture  250  extends from the inner surface  240  to the outer surface  245  and is sized, shaped and located to accommodate the passageway  85  connecting to the collecting reservoir  70 . When the reinforcing rings  230 ,  235  are located about the outer perimeter  80  of the first  45  and second  50  end caps, the pressure handling capacity of the pressure vessel  10  is increased.  
         [0114]    (5) In another variant of the invention, as shown in FIG. 5, means  255  are provided for fastening the upper reinforcing ring  230  to the lower reinforcing ring  235 .  
         [0115]    (6) In still a further variant of the invention, as shown in FIG. 6, a protruding rim  180  is provided. The protruding rim  180  is located at the outer perimeter  80  of the first  45  and second  50  end caps. At least one groove  260  located about the outer perimeter  80  above the protruding rim  180  is provided. At least one groove  260  located about the outer perimeter  80  below the protruding rim  180  is provided. Upper  230  and lower  235  reinforcing rings are provided. Each of the reinforcing rings  230 ,  235  has an inner surface  240 , an outer surface  245  and is formed of high-strength material  246 . Each of the upper  230  and lower  235  reinforcing rings is sized and shaped to fit tightly about the outer perimeter  80  on either side of the protruding rim  180 . Each of the reinforcing rings  230 ,  235  has at least one rib  265  located upon the inner surface  240  thereof. The rib  265  is sized, shaped and located to engage the groove  260 . When the reinforcing rings  230 ,  235  are located about the outer perimeter  80  of the first  45  and second  50  end caps, the pressure handling capacity of the pressure vessel  10  is increased.  
         [0116]    (7) In another variant of the invention, as shown in FIG. 7, means  255  are provided for fastening the upper reinforcing ring  230  to the lower reinforcing ring  235 .  
         [0117]    (8) In yet a further variant of the invention, as shown in FIG. 8, a sintactic foam filler  270  is provided. The foam filler  270  is located within the collecting reservoir  70  of at least one of the first  45  and second  50  end caps. The foam filler  270  has a series of canals  275  through it. Each of the canals  275  connects the orifice  105  of the receptacle  55  to the passageway  85 . An opening  285  in the end caps  45 ,  50  is provided. The opening  285  provides means  286  for introduction of the foam filler  270  into the end caps  45 ,  50 . A sealing plug  290  is provided. The sealing plug  290  is sized and shaped to fit sealably into the opening  285  in the end caps  45 ,  50 . When the foam filler  270  is introduced into the end caps  45 ,  50 , the pressure handling capacity of the pressure vessel  10  is increased.  
         [0118]    (9) In still a further variant of the invention, as shown in FIG. 9, a sintactic foam filler  270  is provided. The foam filler  270  is located within the collecting reservoir  70  of at least one of the first  45  and second  50  end caps. The foam  271  is penetrated by a series of flexible microtubes  291 . Each of the microtubes  291  connects the orifice  105  of the receptacle  55  to the passageway  85 . An opening  285  in the end caps  45 ,  50  is provided. The opening  285  provides means  286  for introduction of the sintactic foam  271  into the end caps  45 ,  50 . A sealing plug  290  is provided. The sealing plug  290  is sized and shaped to fit sealably into the opening  285  in the end caps  45 ,  50 . When the microtubes  291  are connected to the orifices  105  of the receptacles  55  in the end caps  45 ,  50 , the purity of either liquids or gasses stored in the pressure vessel  10  is increased.  
         [0119]    (10) In yet a further variant of the invention, as shown in FIG. 10, an overwrapping of high-strength braiding material  295  is provided. The braiding material  295  extends over the flexible tubes  15  and the first  45  and second  50  end caps. When the flexible pressure vessel  10  is so overwrapped, its pressure-handling capability will be increased.  
         [0120]    (11) In still a further variant of the invention, as shown in FIG. 11, a hoop winding  305  with high-strength materials  306  is provided. The hoop winding  305  extends over the flexible tubes  15  and the first  45  and second  50  end caps. When the flexible pressure vessel  10  is so hoop wound, its pressure-handling capability will be increased.  
         [0121]    (12) In another variant, as shown in FIG. 12, a plastic overcoating  300  is provided. The overcoating  300  further increases the pressure-handling capability of the pressure vessel  10 .  
         [0122]    (13) In yet a further variant of the invention, as shown in FIG. 13, a first flexible blanket  310  is provided. The first blanket  310  has an upper surface  315 , a lower surface  320  and is sized and shaped to cover the pressure vessel  10 . The first flexible blanket  310  extends outwardly beyond the outer edges  325  thereof. The first blanket  310  is fixedly attached at its lower surface  320  to an upper surface  330  of the pressure vessel  10 . A second flexible blanket  335  is provided. The second blanket  335  has an upper surface  340 , a lower surface  345  and is sized and shaped to cover the pressure vessel  10 . The second flexible blanket  335  extends outwardly beyond the outer edges  326  thereof. The second blanket  335  is fixedly attached at its upper surface  340  to a lower surface  355  of the pressure vessel  10 . When the first  310  and second  335  flexible blankets are attached to the pressure vessel  10 , the pressure handling capability of the pressure vessel  10  will be increased.  
         [0123]    (14) In another variant, as shown in FIG. 14, heavy duty stitching  360  is used to attach the first blanket  310  to the second  335  blanket. The stitching  360  penetrates the first  310  and second blankets  335  between the upper  365  and lower  370  cell portions and serves to further reinforce and increase the pressure-handling capabilities of the pressure vessel  10 .  
         [0124]    (15) In still another variant, as shown in FIG. 14, the heavy duty stitching  360  is high pressure hoop and lock braiding  380 .  
         [0125]    (16) In still a further variant of the invention, as shown in FIG. 15A, FIG. 15B, FIG. 15C, FIG. 15D, FIG. 15E, FIG. 15F, FIG. 15G and FIG. 15H, the cross-sectional shape  385  of the outer surface  25  of the flexible tubing  15  is selected from the group comprising: square  390 , triangular  395 , round  400 , hexagonal  405 , ovoid  410 , octagonal  415  and star shaped  420 .  
         [0126]    (17) In yet a further variant of the invention, as shown in FIG. 16A, FIG. 16B, FIG. 16C, FIG. 16D, FIG. 16E, FIG. 16F, FIG. 16G and FIG. 16H, the cross-sectional shape  425  of the inner surface  30  of the flexible tubing  15  is selected from the group comprising: square  390 , triangle  395 , round  400 , hexagonal  405 , ovoid  410 , octagonal  415 , and star-shaped  420 .  
         [0127]    (18) In still a further variant of the invention, as shown in FIG. 17A, FIG. 17B, FIG. 17C, FIG. 17D, FIG. 17E, FIG. 17F, FIG. 17G, FIG. 17H, FIG. 17I and FIG. 17J, the cross-sectional shape  430  of the flexible pressure vessel  10  is selected from the group comprising: square  390 , triangular  395 , round  400 , hexagonal  405 , ovoid  410 , octagonal  415 , pillow shaped  470 , saddle shaped  475 , and a flattened mat shape  480 .  
         [0128]    (19) In yet a further variant of the invention, as shown in FIG. 18A, FIG. 18B, FIG. 18C, FIG. 18D and FIG. 18E, each of the receptacles  55  are of a concave form  485  selected from the group comprising: conical  490 , dome-shaped  495 , ellipsoid  500  and stair-stepped  505 .  
         [0129]    (20) In a variant, as shown in FIG. 18A, FIG. 18B, FIG. 18C, FIG. 18D and FIG. 18E, the first  45  and second  50  ends of each of the flexible tubes  15  are sized and shaped to fit sealably into the receptacles  55 .  
         [0130]    (21) In still a further variant of the invention, as shown in FIG. 19 and FIG. 20, upper  510  and lower  515  reinforcing panels are provided. The reinforcing panels  510 ,  515  are formed of high-strength woven material  520  and are shaped as a form  525  to cover at least half of a surface area  526  of the pressure vessel  10  with extensions  530  projecting from a perimeter  535  of the form  525 . The reinforcing panels  510 ,  515  are joined to the outer surface of the upper  365  and lower  370  cell portions of the hollow pressure cell  10 , thereby increasing the pressure handling capability of the pressure cell  10 .  
         [0131]    (22) In a variant, the method of adhesion is selected from the group comprising: high-strength adhesive, sonic welding and RF welding.  
         [0132]    (23) In another variant, the woven material  520  is prepregnated with either adhesive or laminating material and subjected to heat and pressure.  
         [0133]    (24) An apparatus for fabricating a cellular reservoir flexible pressure vessel  10  may be constructed, as shown in FIG. 21, FIG. 22 and FIG. 23, from the following components. A raw plastic storage and feeding unit  580  is provided. The storage and feeding unit  580  contains a supply of raw plastic  585 . A multi-head extruder  590  is provided. The extruder  590  includes a heating facility  595  and is in communication with the feeding unit  580 . A cooling tank  600  is provided. The cooling tank  600  is located downstream from the extruder  590 . A power puller  605  is provided. The puller  605  serves to pull a tubing bundle  610  from the cooling tank  600 . Core tubing forming dies  615  are provided. The forming dies  615  form the tubing bundle  610  into a predetermined shape  616 . A binder head  620  is provided. The binder head  620  has an attached binder tank  625  containing liquid binder material  640 . A binder applicator  635  is provided. The binder applicator  635  comprises a secondary forming die  640  and serves to affix the binder material  630  to the tubing bundle  610 . A cutting unit  645  is provided. The cutting unit  645  comprises a laser calibration facility  650  and serves to cut the tubing bundle  610  to a predetermined length  655 . A conveyer facility  660  is provided. The conveyer facility  660  comprises means  665  for positioning a cut tubing bundle  610 . A rotating head and ram  670  is provided. The head  670  comprises a glue head applicator  675 . The glue head applicator  675  attaches to a glue tank  680 . A plurality of preformed end caps  45 ,  50  are provided. An automated end cap loader  690  is provided. The end cap loader  690  positions the plurality of end caps  45 ,  50 . An automated end cap installer  691  attached to the automated end cap loader  690  is provided. The installer  691  serves to attach the end caps  45 ,  50  to the tubing bundle  610 . A high-intensity UV lamp assembly  695  is provided. The lamp assembly  695  serves to cure the glue  700 .  
         [0134]    (25) In a variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 23, a plurality of reinforcing rings  195  is provided. The reinforcing rings  195  are formed of high-strength material  206 . A reinforcing ring auto loader  710  is provided. A swivel ram  715  is provided. The ram  715  comprises of a ring loading and placement head  720 . The swivel ram  715  is in cooperation with the ring auto loader  710  and serves to press the reinforcing ring  195  onto the pressure vessel  10 .  
         [0135]    (26) In another variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 24, either a gas or liquid supply tank  730  is provided. An auto loader test head  735  is provided. The test head  735  is adaptable to fittings on the end caps  45 ,  50 . A cryogenic test unit  740  in communication with the test head  735  is provided. The test head  735  and the test unit  740  provides means  745  for pressurizing the pressure vessel  10 .  
         [0136]    (27) In yet a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 24, reinforcing blanket material  750  is provided. A glue spraying mechanism  755  is provided. The mechanism  755  comprises glue tanks  760 , glue spray heads  765  and glue for attaching the blanket material  750  to the pressure vessel  10 . A blanket material feed mechanism  775  is provided. A press forming tool  780  is provided. The tool  780  is adapted to form the blanket material  750  over the cut tubing bundle  610  and the attached end caps  45 ,  50 .  
         [0137]    (28) In a variant, as shown in FIG. 24, a high-strength thread  785  is provided. A stitching head  790  is provided. The stitching head  790  is adapted to sew the high-strength thread  785  through the reinforcing blanket material  750 .  
         [0138]    (29) In still a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 25, includes a high-strength braiding material  795 . A braider  800  is provided. The braider  800  is adapted to position and provide overwrapping  805  of the pressure vessel  10  with the braiding material  795 . A binder spraying mechanism  810  is provided. The spraying mechanism  810  comprises a binder tank  815 , a binder spray head  820  and binder material  825 .  
         [0139]    (30) In yet a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 26, a high-strength reinforcing ribbon  830  is provided. An automated reinforcing ribbon winding machine  835  is provided. The winding machine  835  comprises of a reinforcing ribbon spool  840  and an auto layout ribbon head  841 . A binder spraying mechanism  810  is provided. The spraying mechanism  810  comprises a binder tank  815 , a binder spray head  820  and binder material  825 .  
         [0140]    (31) In still a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 27, means  850  are provided for pulling a series of high tensile strength core wires  855  through orifices  105  in receptacles  55  in the end caps  45 ,  50  to a passageway  85  in the end caps  45 ,  50 . Means  870  are provided for injecting sintactic foam  270  through an opening  285  in the end caps  45 ,  50 . Means  880  are provided for attaching a sealing plug  290  to the opening  285 . Means  890  are provided for removing the core wires  855  from the end caps  45 ,  50 . When the core wires  855  are removed from the end caps  45 ,  50 , a series of canals  275  will be formed in the sintactic foam  270  connecting orifices  105  in receptacles  55  in the end caps  45 ,  50  to the passageway  85 .  
         [0141]    (32) In yet a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 28, means  900  are provided for attaching a series of flexible microtubes  291  to orifices  105  in receptacles  55  in the end caps  45 ,  50  to a passageway  85  in the end caps  45 ,  50 . Means  870  are provided for injecting sintactic foam  270  through an opening  285  in the end caps  45 ,  50 . Means  880  are provided for attaching a sealing plug  290  to the opening  285 . Means  925  are provided for removing the core wires  855  from the end caps  45 ,  50 . When the microtubes  291  are connected to the passageway  85 , the pressure vessel  10  will provide an ultra clean environment for either liquids or gasses.  
         [0142]    (33) In still a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 29 and FIG. 29A, means  930  are provided for forming a concave receptacle  935  having a shape selected from the group comprising: conical  490 , dome-shaped  495 , ellipsoid  500  and stair-stepped  505 .  
         [0143]    (34) In a variant, a shown in FIG. 30, means  960  are provided for forming the first  35  and second  40  ends of each of the flexible tubes  15  to fit sealably into the receptacles  55 .  
         [0144]    (35) In yet a further variant of the apparatus for fabricating a cellular reservoir flexible pressure vessel  10 , as shown in FIG. 31, means  940  are provided for forming upper  510  and lower reinforcing panels  515 . The reinforcing panels  510 ,  515  are formed of high-strength woven material  520  and are shaped as a form  525  to cover at least half of a surface area  526  of the pressure vessel  10  with extensions  530  projecting from a perimeter  535  of the form  525 . Means  531  are provided for adhering the reinforcing panels  510 ,  515  to the outer surface of the upper  365  and lower  370  cell portions of the hollow pressure cell  10 , thereby increasing the pressure handling capability of the pressure cell  10 .  
         [0145]    (36) In a variant, as shown in FIG. 32, the method of adhesion is selected from the group comprising: high-strength adhesive  945 , sonic welding (not shown) and RF welding (not shown).  
         [0146]    (37) In a final variant, the woven material  520  is prepregnated with either adhesive or laminating material and subjected to heat and pressure.