Abstract:
An airbed mattress includes a valve for controlling inflation of the mattress. The valve is normally biased to a closed position to prevent changes in the mattress&#39; level of inflation. The valve may be opened by introduction of an air pump. The valve and air pump are designed to operate cooperatively by employment of an adaptor to facilitate the introduction of the air pump. The valve has an air passageway which contains an internal airflow control assembly. The control assembly operates to open the valve to passage of air upon introduction of the air pump and adaptor as well as effecting the closing of the valve when the air pump and adaptor are withdrawn. The valve also may have an extension adapted for a releasable connection with an air pump and adaptor for holding the valve open.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     REFERENCE TO A MICROFICHE APPENDIX 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     Airbeds have increased in popularity due in part to flexibility of use, ease of set-up and reduction of storage space—all without sacrifices in comfort. An airbed&#39;s level of inflation may be adjusted by adding or removing air through a port, optionally in combination with a source of air such as a pump. A valve typically controls airflow through the port and usually operates in concert with an air pump. 
     An airbed valve preferably has an open mode to enable air passage into and out of the airbed, and a closed mode to maintain the airbed&#39;s level of inflation when in use. Preferably the valve can switch readily between modes with minimal actions beyond the introduction of the air pump. The airbed and valve preferably are reliable, compatible with bedding materials, strong enough for frequent long term use, and relatively inexpensive to manufacture. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an apparatus which provides selective control of an airbed&#39;s level of inflation by movement of air into or out of the airbed. 
     Another object of the present invention is to provide an airbed inflation control apparatus which is easy to use in a variety of applications. 
     A further object of the present invention is to provide an airbed inflation control apparatus of rugged and simple construction which is relatively inexpensive yet operates reliably. 
     Other objects and features will be in part apparent and in part pointed out hereinafter. 
     In a first aspect of the present invention an inflatable and deflatable airbed includes an airtight membrane having an interior and an exterior, the membrane being inflatable by adding air to the interior of the membrane. A valve controls passage of air into and out of the membrane, the valve having a longitudinal axis and including a housing. The housing defines an air passageway into the interior of the membrane, the air passageway having a greater radius inside of the membrane than outside the membrane. The air passageway contains an airflow control assembly that includes a longitudinally movable plug sized to fit in and move in the air passageway. The housing has an interior end that is spanned by a housing base, the housing base having at least one aperture open to air flow between the air passageway and the interior. The airflow control assembly biases the plug toward the exterior of the membrane. When the plug is forced against the housing in response to the bias, it forms an airtight closure to prevent airflow through the air passageway. When the plug is moved in a direction opposite to the bias, it opens the valve to air flow through the air passageway. 
     A second aspect of the present invention includes the airflow control valve used in connection with such an airbed. 
     A method of connecting an air pump with the inventive airflow control valve to inflate the airbed is also disclosed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross-sectional view of a valve apparatus of the present invention along with representations of a cap and an adaptor device for interconnection with an air pump. 
     FIGS. 2 and 2A are expanded cross-sectional views of alternatives of the airflow control assembly of the valve apparatus of the present invention wherein the valve apparatus is depicted in a closed configuration. 
     FIG. 3 is a further expanded view of FIG. 2 depicting details of an interior shelf portion of the valve apparatus of the present invention wherein the valve apparatus is depicted in a closed configuration. 
     FIG. 4 is an expanded cross-sectional view of the airflow control assembly of the valve apparatus of the present invention wherein the valve apparatus is depicted in an open configuration. 
     FIG. 5 is a further expanded view of FIG. 4 depicting details of an interior shelf portion of the valve apparatus of the present invention wherein the valve apparatus is depicted in an open configuration. 
     FIG. 6 is an expanded cross-sectional view of a valve apparatus  110  according to a second embodiment of the present invention. 
     FIG. 7 is a perspective view of an adaptor  211  according to a third embodiment of the present invention. 
     FIG. 8 is a view, in the direction  20  of FIG. 1, of an external section of an alternative valve housing  241  according to a third embodiment of the present invention. 
     FIG. 9 is a view of an alternative structure for the valve plug. 
    
    
     Similar reference characters indicate similar parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, an airbed  8  (only a portion of which is shown), with a valve apparatus  10  according to a first embodiment of the present invention is depicted with an adaptor  11 . The adaptor  11  opens the valve apparatus  10  for introduction of an air pump (not depicted). The adaptor  11  has an end projection  13 . The end projection  13  is depicted in one of a variety of configurations available, subject to the operational requirements that the adaptor end projection  13  fit in flush contact about a perimeter area of the valve and is configured such that the end projection  13  is able to open the valve. End projection  13  is further configured so that when the end projection  13  opens the valve a free flow of air from the pump to the valve as well as from the valve to the pump is not impeded. An end cap  14  for closure of the valve assembly when the airbed&#39;s inflation level is not being altered is attached with a tether  16 . An arrow  20  lies along the longitudinal axis of the valve apparatus  10  and indicates the direction of airflow when the airbed  8  is being inflated. The valve apparatus  10  is generally rotationally symmetrical about the longitudinal axis which arrow  20  lies along. An internal inflatable region  30  of the airbed  8  is contained within a membrane  18 , a portion of said membrane  18  about the valve&#39;s circumference being airtight sealed to a radial extension  22  girdling the perimeter of the valve apparatus  10 . Said membrane and contiguous valve parts define a boundary surface dividing an external region  28  of the airbed  8  from an internal region  30 . Within an interior  32  of the valve apparatus  10  is contained an airflow control assembly  33 . The airflow control assembly  33  includes a solid plug  34 . 
     Referring now to FIG. 2, the valve apparatus  10  is depicted when maintaining a constant airbed 8 degree of inflation, such as when the airbed  8  is in use, wherein the plug  34  is at its maximum externally directed location. The plug  34  has an external end surface  36 , a plug side surface  38 , and an internal end  40 . End projection  13  pressing on the external end surface  36  in the direction  20  opens the valve apparatus  10  for introducing the adaptor  11 . The valve apparatus  10  has a housing  41 . The housing  41  has an external section  42 . Around the exterior of the terminal end of the housing external section  42  is a threaded portion  44  for receiving the screw-on cap  14 . The plug side surface  38  fits in flush contact with an interior surface  46  of the housing external section  42 . A plug seat  50  is affixed to the internal end  40  of the plug  34 . A post  52  extends internally from the plug seat  50 . The plug seat  50  substantially spans nearly all of the width of a valve apparatus housing internal section  54 . The post  52  is slidably received within a post guide  56  which is part of a fixed housing base  58 . A spring  60  biases the plug seat  50  in the external direction away from the fixed housing base  58  to effect a normal plug and plug seat position at the limit of their externally directed movement. A scallop member  62  (depicted schematically) disposed within the apparatus interior  32  is fixedly connected to the housing base  58  and limits the internally directed travel of the plug and plug seat. The plug  34 , plug seat  50 , post  52 , post guide  56 , housing base  58 , spring  60  and scallop member  62  are parts of the airflow control assembly  33 . Apertures  64  (depicted schematically) are passageways for airflow between the apparatus interior  32  and the internal region  30 . 
     As can be seen in FIG. 2A, the plug  34  may be of various shapes. Although the plug is smoothly tapered in FIG. 2, in FIG. 2A it has steps shown at  34 S that extend circumferentially around the plug. The housing is varied in shape in this embodiment to accommodate the stepped plug. Although a single step is shown, a number of steps may be formed in plug  34 . Moreover, although the housing is shown as shaped to accommodate the stepped plug, it should be realized that steps may be formed with radii such that the tapered housing of FIG. 2 may still be used. In that case, the main sealing action would occur between the point of the step and the housing, rather than along the sides of the step. Of course, the precise place where such sealing occurs is of minor importance so long as sealing occurs. 
     Referring next to FIG. 3, an enlarged view in detail of the area indicated with the dashed circle in FIG. 2 is depicted showing a juncture of the plug and plug seat with an interior shelf  65  of the housing  41 . A resilient pad  70 , which may be composed of a variety of compressible materials but is preferably foam rubber, is attached to the interior shelf  65 . When the plug  34  is at its limit of externally directed travel, an internally facing surface  72  of pad  70  is pressed upon by an externally facing surface  75  of the outermost portion of plug seat  50  and by an externally facing surface  76  of the plug  34 . Contact of the surface  72  with the surfaces  75  and  76  obstructs airflow through the valve interior  32 . The obstruction of airflow through the valve interior  32  prevents airflow into or out from the internal region  30 , thereby blocking changes in the airbed  8  level of inflation. 
     FIGS. 4 and 5 depict the same elements in the same views as in FIGS. 2 &amp; 3, respectively, differing only by the plug  34  and plug seat  50  being at their internally directed limit of movement. The internally directed motion of valve apparatus  10  is caused by introduction of adaptor  11  and projection  13  (not depicted). At its limit of internally directed travel the plug seat  50  contacts the scallop  62 . Air passageways between the surface  38  and the surface  46 , and between the surfaces  75  and  76  and the surface  72  are opened by the internally directed movement of the plug seat  50 . These passageways enable inflation or deflation of the membrane  18  by airflow through the valve interior  32 . 
     While a wide variety of materials and compositions of matter can serve well to construct the present invention, the plug  34  is preferably composed of rubber and the plug seat  50  of plastic. 
     Referring now to FIG. 6, which is a cross-section view of a valve apparatus  110  that is modified in three ways from the valve apparatus  10  of the first embodiment. A first modification is the absence of the resilient pad  70 , which is attached to the interior shelf  65  in the first embodiment. The space occupied by pad  70  in the first embodiment is an unoccupied part of the valve interior  132  in the second embodiment. When a plug  134  is at the limit of its externally directed movement, plug side surface  38  fits in flush contact with interior surface  46  to obstruct airflow through the valve apparatus  110 . When the plug  134  is moved in the internal direction  20 , air passes between plug side surface  38  and housing interior surface  46 , thereby allowing airflow through the valve apparatus  110 . 
     A second modification is to an external end surface  136  of plug  134 . In the second embodiment, a corner ring  135  circles the outer border of external end surface  136 . Corner ring  135  is preferably a hard plastic, but may be constructed of any material with the suitable properties. These properties are sufficient durability to withstand repeated pressings by the end projection  13  without significant structural degradation; and a surface which produces relatively low friction when contacting the interior surface  46 . End projection  13  is formed from a cylindrical shell with a relatively narrow radial thickness. Corner ring  135  extends from the outer edge of the external end surface  136  towards the axial center of plug  134  sufficiently far to cover the entire contact area of end projection  13  with plug  134 . The depth of corner ring  135  along the side  38  is sufficiently far to ensure that housing interior surface  46  only contacts corner ring  135  when the plug  134  is moving. In operation, corner ring  135  provides at least two benefits. First, the durability of corner ring  135  prevents damage to the plug  34  from repeated pressings by adaptor  13 . Second, the lesser friction between interior surface  46  and the material of corner ring  135 , versus the material of plug  134 , allows plug  134  to more readily travel to its external limit of movement, for a faster and more complete closing of the valve. The desired degree of inflation of airbed  8  is thus easier to keep, once reached, since the quicker, complete closing of the valve reduces the escape of air. 
     A third modification is to the parts within the valve interior  132  which direct and control the motion of the plug  134 . In the second embodiment, the post  52  of the first embodiment is now a post guide  152  that extends in an internal direction from a plug seat  150 . The post guide  56  of the first embodiment is now a post  156  that extends in an external direction from a housing base  158  in the second embodiment. Post  156  and post guide  152  are also of greater width than post  52  and post guide  56  are in the first embodiment. This greater width, preferably in combination with a close fitting of post guide  152  to post  156 , reduces undesired plug  134  movement in a direction transverse to direction  20  when the valve apparatus  110  is open. A spring retaining guide  157  extending from housing base  158  encircles the perimeter of spring  60 . Spring retaining guide  157  maintains the desired positioning of the spring  60  during movement of plug  134 . The scallop  62  of the first embodiment is absent in the second embodiment. A plurality of bars  162  extend in an internal direction from plug seat  150  to a fraction of the depth of the valve interior  132 . Bars  162  contacting housing base  158  arrest the internally directed motion of plug  134 . While bars  162  are depicted as being longer than the height of spring retaining guide  157 , in an alternative embodiment spring retaining guide  157  may be equal or greater in height than the length of bars  162 , so that the internally directed movement of the plug  134  is arrested by contact of the plug seat  150  with the spring retaining guide  157 . 
     Referring now to FIG. 7, an alternative adaptor  211  to be optionally used instead of adaptor  11  when introducing an air pump  8  into valve  10  (or valve  110 ). The adaptor  211  is specifically configured to work in cooperation with an alternative valve housing  241  depicted in FIG. 8, described subsequently. Adaptor  211  differs from adaptor  11  by an alternative end projection  213 . A collar  214  and a plurality of legs  218  comprise end projection  213 . Formed within collar  214  are a trio of vertical inset slots  215  connecting to a trio of horizontal slots  217 . Each of slots  215  originate from a site in collar  214  midway between legs  218 . 
     Alternative valve housing extension  241  is configured to operate cooperatively with adaptor  211 . From the perspective along the direction  20 , an alternative housing interior surface extension  246  is seen in FIG.  8 . Housing extension  241  extends externally above the external movement limit of plug  34 , providing space external of plug  34  but still inside the confines of housing extension  241 . Within this space, a trio of pegs  247  extend from the interior surface extension  246 . Pegs  247  are spaced to simultaneously align with slots  215 , and are sized to fit in slots  215  when adaptor  211  moves in the direction  20 . Adaptor  211  moving in direction  20  opens the valve apparatus  10 . Once at the limit of slots  215 , the adaptor  211  is rotated clockwise, if viewed along direction  20 . The rotation fits pegs  247  into slots  217 . Once in slots  217 , pegs  247  cannot move opposite to the direction  20  until the adaptor  211  is rotated counterclockwise to bring pegs  247  back to slots  215 . The slots  215  and pegs  247  are thus able to selectively keep the adaptor in place when holding the valve apparatus open without requiring the user to continuously exert force to overcome the bias holding the valve closed. The cooperative action of adaptor  211  and housing extension  241  provides an easily securable and releasable connection between the valve apparatus  10  (or  110 ) and an air pump (not depicted). Since the pump takes at least some number of seconds to alter the airbed 8 degree of inflation, the securable connection provided by adaptor  211  and housing extension  241  allows the user to engage in other activities during this time. Alternatively, the slots  215  and  217  could be formed in the housing extension  241 , and the pegs  247  could extend from the adaptor  213  to provide the same benefit. Still another alternative would be to have either the slots or pegs formed into a part of the air pump itself, with the corresponding pegs or slots formed in the housing extension  241 , if that air pump is configured to fit directly into the valve apparatus without need of an adaptor  213 . The configuration of slots and pegs described in the third embodiment of the present invention are intended to be merely illustrative and not limiting. It is projected that a multitude of differing cooperative elements can provide functional benefits similar to the pegs and slots, as is well known to those of skill in the art, without departing from the scope of the present invention. 
     Turning to FIG. 9, an alternative valve  10 A is shown in simplified form (with the biasing spring and structure removed for clarity). Valve  10 A includes a plug  34 A that mates with the conical section of the valve body but stops short of the exterior end of the valve body. In this embodiment, the plug does not extend into the part of the passageway (labeled  250 ) surrounded by the threads  44 . The interior portion of plug  34 A has a thick rubber flange (for example, about {fraction (1/16)}″ in thickness) that extends around the circumference of the plug body (for example, extending ½″ out from the plug body). This integral flange  251  mates against a suitable sealing surface  253  to provide additional sealing. Of course, other minor variations in the shape and size of the plug and the housing could be used as well. 
     In the disclosure of the present invention the bed is described as being inflated by air but it should be understood that “air” as used herein is a generic term for any desirable inflation gas. In view of the above, it will be seen that the various objects and features of the invention are achieved and other advantageous results obtained. The examples contained herein are merely illustrative and are not intended in a limiting sense.