Abstract:
This invention is an inflatable product that includes a plurality of chambers at least two of which are adjoining, with at least one unidirectional valve connecting any pair of adjoining chambers, an inlet port, and an exhaust port.

Description:
BACKGROUND OF INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to inflatable products, and more particularly, to inflatable furniture such as mattresses, chairs and the like, which are easily inflated and deflated.  
           [0003]    2. Discussion of Related Art  
           [0004]    Inflatable furniture such as air mattresses and chairs have enjoyed wide popularity for a number of reasons. When not is use, such inflatable products occupy a small area in relation to their inflated size and are thus easily stored and transported. When inflated, a piece of inflatable furniture provides its user with a high level of comfort as he or she is literally supported upon a cushion of air isolating him or her from an uncomfortable resting surface such as a floor or the uneven terrain often associated with outdoor excursions.  
           [0005]    Although inflatable furniture is relatively inexpensive and enjoys the advantages recited above, such products have never gained universal acceptance by the consuming public and are not seen as entirely suitable replacements for conventional furniture. One of the primary reasons for this lack of universal acceptance is that inflatable furniture, at least to date, has not been capable of fast and efficient inflation while at the same time providing its user with a level, firm and stable supporting surface. This is because conventional inflatable furniture tends to be constructed such that all parts are in fluid communication which results in a characteristic “give” caused by the redistribution of fluid which occurs when the user applies a downward force on the furniture. Even though certain structural methods have been used to reduce this bulging effect, such as I-beam stabilization, such methods only partially address the bulging problem because fluid redistribution still occurs during use. When this redistribution occurs, the resultant bulging and compressing of the inflatable product can cause a loss of evenness and stability.  
           [0006]    Attempts have been made to address this perceived shortcoming in several different ways. For example, U.S. Pat. No. 3,705,429 discloses an inflatable mattress which uses a plurality of individual inflatable beams, columns or chambers within an outer inflatable chamber. Each beam or chamber is separately inflatable and independent, having its own inlet/outlet port, without fluid communication between contiguous chambers. Although this design may prevent the redistribution of fluid between chambers during use, it has another shortcoming. Each independent chamber must be inflated and deflated through multiple inlet ports, thus the task of inflating and deflating the mattress can prove lengthy or tedious to the user.  
           [0007]    Therefore, there is a need for an inflatable product that allows for fluid communication between contiguous chambers during inflation, thus allowing for easy inflation from a single inlet port, while at the same time maintaining product firmness and stability by preventing the bulging associated with the redistribution of fluid during use. The present invention accomplishes these goals and overcomes the inadequacies of the prior art.  
         SUMMARY OF THE INVENTION  
         [0008]    It is the object of the present invention to provide an inflatable product which characteristically maintains its firmness and stability while not being overly complex to produce and maintain.  
           [0009]    A further object of the present invention is to provide an inflatable product that demonstrates a firmness and stability similar to that of conventional furniture.  
           [0010]    It is a further object of this invention to provide an inflatable product that can be readily inflated and deflated.  
           [0011]    Additional features and advantages of the invention will be set forth in the description which follows, and will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as in the drawings.  
           [0012]    The present invention comprises an inflatable product having a plurality of chambers with at least two of said chambers adjoining one another in whole or in part, at least one unidirectional valve connecting any pair of adjoining chambers, an inlet port through which fluid can be introduced into said product, and an exhaust port through which fluid can exit said inflatable product.  
           [0013]    It is to be understood that the foregoing general description and the following detailed description are exemplary and intended to provide a further explanation of the invention as claimed. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.  
         [0015]    [0015]FIG. 1 is a partial sectional view of the first embodiment of an inflatable mattress with adjoining inner and outer chambers having an interconnecting unidirectional valve.  
         [0016]    [0016]FIG. 2 is a cross-sectional view of a second embodiment of an inflatable mattress with stacked multiple chambers having an interconnecting unidirectional valve.  
         [0017]    [0017]FIG. 3 is a perspective view of a unidirectional valve suitable for use in the invention which is biased in a closed position by a spring.  
         [0018]    [0018]FIG. 4 is an exploded view of the unidirectional valve of FIG. 3.  
         [0019]    [0019]FIG. 5 is a top plan view of the unidirectional valve of FIG. 3.  
         [0020]    [0020]FIG. 6 is a cross-sectional view of the unidirectional valve of FIG. 5 taken along line  6 - 6 .  
         [0021]    [0021]FIG. 7 is a perspective view of the mounting boot for the unidirectional valve of FIG. 3. 
     
    
     DETAILED DESCRIPTION  
       [0022]    [0022]FIG. 1 illustrates the first embodiment of the present invention. In particular FIG. 1 illustrates a partial-sectional view of an inflatable mattress  100 , which comprises an inner chamber  101  surrounded by an outer chamber  102 . The outer chamber  102  is formed by the sealing or joining of the top layer  103  and bottom layer  105  to the outer wall  104  along an upper outer wall seam  106  and a lower outer wall seam  107 . The inner chamber  101  is formed by sealing or joining the top layer  103  and bottom layer  105  to the inner wall  108  along an upper inner wall seam  109  and a lower inner wall seam  110 . A tube  111  allows for the introduction of fluid into the inner chamber  101 . The tube  111  is sealed within the outer wall  104  at a circular seam  112  about the periphery of tube  111  and into the inner wall  108  by a second circular seam  113  about the periphery of tube  111 .  
         [0023]    In both the first and second embodiments the materials forming the walls, layers and tube comprise a flexible and resilient material such as polyvinyl chloride sheeting (or PVC), thermoplastic impregnated cloth or other materials known to one having ordinary skill in the art. The seals between the walls, layers and tube are formed using radio frequency (RF) sealing or other processes known to one having ordinary skill in the art.  
         [0024]    According to the first embodiment of the inflatable mattress  100  shown in FIG. 1 the inner chamber  101  and outer chamber  102  are inflated through a single inlet port  114  of the tube  111  using an electro-mechanical pump  115  inserted into the edge of the tube  111 . The pump can be affixed to the outer edge of the mattress for use as needed. Fluid is first introduced into the inner chamber  101  after which some fluid passes through an unidirectional valve  300  into the outer chamber  102 . Once the inner chamber  101  and outer chamber  102  are inflated, the unidirectional valve  300  prevents the reverse flow of fluid from the outer chamber  102  back into the inner chamber  101 , as could occur for a number of reasons such as by the application of force by a user&#39;s body on the mattress.  
         [0025]    The air pressure in the inner chamber  101  can be adjusted through a deflation valve contained in the electro-mechanical pump  115 . In such usage when air is released from the inner chamber  101 , air pressure in the outer chamber  102  remains constant as the unidirectional valve  300  prevents the back flow of air from the outer chamber  102  into the inner chamber  101 . Thus differentiated pressures can be maintained in the inner and outer chambers.  
         [0026]    Deflation of the entire air mattress  100  can be accomplished by the opening of the exhaust port  116  which is sealed within the outer wall  104 . When the exhaust port  116  is opened, the pressure in the outer chamber will decrease. The resulting air pressure change will cause the unidirectional valve  300  to open allowing the passage of air from the inner chamber  101  into the outer chamber  102  and out the exhaust port  116 .  
         [0027]    [0027]FIG. 2 represents a second embodiment of the invention. Particularly FIG. 2 represents a cross-sectional view of an inflatable mattress  200  wherein the multiple chambers of the air mattress  200  are comprised of an upper chamber  201  and a lower chamber  202 . The upper chamber  201  and lower chamber  202  are formed by first sealing a top layer  203  to an upper side wall  206  along a seam  209 . Next the middle layer  204  is sealed to both the upper side wall  206  and the lower side wall  207  along a seam  210 . Finally, the bottom layer  205  is sealed to the lower side wall  207  along a seam  211 . In addition, a tubular chamber  208  acts as a base preventing lateral movement the mattress  200 , and is in fluid communication with the lower chamber  202 .  
         [0028]    The air mattress  200  can be inflated by introducing fluid through the inlet port  212  using an electro-mechanical pump  213  attached to the upper chamber  201 . As fluid is introduced, it will pass into the upper chamber  201  through the unidirectional valve  300  into the lower chamber  202  and the tubular chamber  208 . As with the first embodiment, when all chambers are filled the unidirectional valve  300  will prevent the reverse flow of fluid from the lower chamber  202  into the upper chamber  201 .  
         [0029]    The upper chamber  201  of the air mattress  200  can also be partially deflated by a valve incorporated within the electro-mechanical pump  213 . As in the first embodiment the partial deflation of the upper chamber  201  will not affect the air pressure of the lower chamber  202  due to the restriction of air flow by the unidirectional valve  300 .  
         [0030]    Deflation of the mattress  200  can be accomplished by the opening of the exhaust port  214  which is within the lower wall  207  resulting in the decrease of the pressure in the lower chamber. The decreased fluid pressure in the lower chamber  202  will allow for the opening of the unidirectional valve  300  which in turn will allow for the passage of the fluid in the upper chamber  201  to pass through to the lower chamber  202  and finally through the exhaust port  214 .  
         [0031]    [0031]FIGS. 3-7 depict a valve suitable for use in the present invention, a spring loaded unidirectional valve. The valve comprises a movable valve element  301  and gasket  302 . The gasket can be made of rubber or other suitable gasket material known to those having ordinary skill in the art. The movable valve element  301  is biased in a closed position against the valve seat  311  by a partially compressed resilient coil spring  303 . The spring  303  is held in place about the shaft  305  of the movable valve element  301 by a retaining washer  304  affixed to said shaft.  
         [0032]    The movable valve element  301  will move vertically with respect to the valve seat  311  through the central sleeve  306  thereby opening the unidirectional valve  300  when sufficient pressure is exerted on the movable valve element  301  to overcome the biasing tension created by the partially compressed spring  303 .  
         [0033]    The central sleeve  306  is an integral part of the valve body  307  and is attached to the valve body  307  by three triangular shaped support arms  308  which are integral with both the central sleeve  306  and the valve body  307 .  
         [0034]    In the first embodiment, the unidirectional valve  300  is mounted within the air mattress  100  such that it permits the unidirectional flow of air between the inner chamber  101  and the outer chamber  102 . The mounting is accomplished by attaching a standard mounting boot  400 , as shown in FIG. 7, approximately midway between the upper layer  103  and the lower layer  105  in the inner wall  108 . The mounting boot has a male-threaded portion  401  capable of being received by the complementary female thread  312  of the unidirectional valve  300 . The male threaded portion of said mounting boot is sealed to the inner wall  108  forming a seal  402  tight enough to prevent fluid leakage.  
         [0035]    Once the valve is attached to the inner wall  108  the inlet side of the valve  309  will be in  20  communication with the inner chamber  101  while the outlet side of the valve  310  will be in communication with the outer chamber  102 .  
         [0036]    In the second embodiment, the unidirectional valve  300  is mounted in the same manner as in the first embodiment except that the unidirectional valve  300  is mounted in between the upper chamber  201  and the lower chamber  202 . Thus, the inlet side of the valve  309  will be in communication with the upper chamber  201  and the outlet side of the valve  310  will be in communication with the lower chamber  202 .  
         [0037]    It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing form the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.