Abstract:
A valve is provided having an air gap to protect against backflow in a fluid system. The valve can also be used to control fluid flow while providing such backflow protection. The valve can be used with e.g., a reverse osmosis water filtration system and/or other systems. By incorporating both backflow protection and flow control into the same device, efficiencies in space, complexity, and/or installation time are provided.

Description:
FIELD OF THE INVENTION 
       [0001]    The subject matter of the present disclosure relates generally to a valve or diverter that provides an air gap or break to protect against backflow. 
       BACKGROUND OF THE INVENTION 
       [0002]    Certain fluid systems can require protection against backflow from e.g., a drainage or sewage system. For example, a dishwashing appliance is typically connected to a drain line leading to a sewage system for allowing wastewater from cleaning operations to be fed to the sewage system. However, under certain conditions, waste fluid may attempt to backflow undesirably from the sewage system into the drain line and into the dishwashing appliance. By way of additional example, certain water filtration systems—such as reverse osmosis systems—may create wastewater that is fed to a drainage or sewage system. This waste or reject water contains contaminants filtered from the water. The backflow of this wastewater from the sewage system to the water filtration system is also undesirable. Accordingly, with these and other applications, it is desirable to provide protection against such backflow. Building codes and other government regulations may require that such protection be provided. 
         [0003]    One device that can be used to prevent backflow is a check valve. A common construction uses a spring that forces a ball or other element against a port to seal off backflow through the port. When fluid flows in the proper direction, it pushes the ball and compresses the spring, thereby allowing fluid to flow through the port. However, if fluid attempts to backflow through the port, the flow is in the same direction of action as the spring, and the fluid and spring act together to force the ball against the port and thereby prevent such backflow. 
         [0004]    A check valve can lose its ability to operate correctly due to e.g., hysteresis of the spring. In addition, the check valve is typically an additional, separate element that must be installed in a fluid system, thereby adding to the overall complexity and expense. As an additional item, the check valve will also consume additional space. For certain applications, such as a kitchen sink or within cabinetry, such additional space may be unavailable or its use for a check valve or other backflow prevention device may be undesirable. 
         [0005]    Accordingly, a device for protecting against backflow in a fluid system would be desirable. More particularly, a device that can protect against backflow and that can be incorporated within a valve to provide additional functionality and space savings would be beneficial. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0006]    The present invention provides a valve that provides an air gap or break to protect against backflow in a fluid system. The valve can also be used to control fluid flow while still providing such backflow protection. The valve can be used with e.g., a reverse osmosis water filtration system and/or other systems. By incorporating both backflow protection and flow control into the same device, efficiencies in space, complexity, and/or installation time are provided. Additional aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention. 
         [0007]    In one exemplary embodiment, the present invention provides a valve for preventing backflow. The valve includes a main body having a first primary inlet; a primary outlet; a secondary inlet; a secondary outlet; and a secondary fluid channel connecting the secondary inlet with the secondary outlet, the secondary fluid channel defining a gap connected with an ambient that is exterior to the valve. The valve also includes a rotatable valve element positioned within the main body. The valve element is selectively rotatable between a position placing the first primary inlet in fluid communication with the primary outlet, and a position disconnecting the first primary inlet from fluid communication with the primary outlet. 
         [0008]    In still another exemplary embodiment, the present invention provides a diverter valve that includes a cylindrical main body having a longitudinal axis extending along a vertical direction when the valve is mounted. The main body includes a first primary inlet; a primary outlet; a secondary inlet; a secondary outlet; and a secondary fluid channel continuously connecting the secondary inlet with the secondary outlet. The secondary fluid channel defines a gap that is in fluid communication with an ambient exterior to the valve and is located along a flow direction of the fluid channel that is between the secondary inlet and the secondary outlet and above the secondary inlet and the secondary outlet along the vertical direction. A valve element is positioned within the main body. The valve element is selectively movable between a first position placing the first primary inlet in fluid communication with the primary outlet and a second position disconnecting the first primary inlet from fluid communication with the primary outlet. 
         [0009]    These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which: 
           [0011]      FIG. 1  provides a cross-sectional view of an example of a kitchen counter-top onto which an exemplary diverter valve of the present invention is mounted. 
           [0012]      FIG. 2  is a perspective view of an exemplary diverter valve of the present invention. 
           [0013]      FIG. 3  is a perspective and cross-sectional view of the exemplary diverter valve of  FIG. 2 . 
           [0014]      FIG. 4  is a cross-sectional view of the exemplary diverter valve of  FIG. 2  with the cross-section taken along the same plane as  FIG. 3 . 
           [0015]      FIG. 5  is another cross-sectional view of the exemplary diverter valve of  FIGS. 2 and 3 . The cross-sectional plane of  FIG. 5  is orthogonal to the cross-sectional plane of  FIG. 4 . 
           [0016]      FIG. 6  is a cross-sectional view taken along the same plane as  FIG. 5  but showing the valve element in a different position than in  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0017]    Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
         [0018]      FIG. 1  provides an example of an application of an exemplary embodiment of a diverter valve  100  for preventing backflow. More particularly,  FIG. 1  is a cross-sectional view of a kitchen sink  50  and countertop  54 . Diverter valve  100  is mounted onto countertop  54 . A dial on handle  102  is visible to the user above top surface  56  of countertop  54  while a main body  122  of valve  100  extends through an opening  74  in countertop  54 . A kitchen application is provided by way of example only; diverter valve  100  may be used in other applications as well. 
         [0019]    Kitchen sink  50  includes a faucet  52  that is connected with (or in fluid communication with) a hot water supply  58  and a cold water supply  68 . Sink  50  is also connected with drain lines  70  that feed waste fluids (i.e., water that may contain foods, soils, etc.) to a drain or sewage  72 . For example, sewage  72  could lead to a septic tank or to a sewage pipe connected with a municipal waste treatment station. 
         [0020]    Diverter valve  100  allows a selection of water for supply line  68 . More particularly, and by way of example, line  60  provides unfiltered water to a first primary inlet  106  of diverter valve  100  while line  62  provides filtered water to a second primary inlet  108  of diverter valve  100 . By rotating handle  102 , a user can select whether filtered or unfiltered water will be provided to faucet  52  at sink  50 . As will be more fully described, the rotation of handle  102  can be used to place either line  60  or line  62  into fluid communication with the primary outlet  110  of diverter valve  100  and thereby provide filtered or unfiltered water through line  68  to faucet  52  as selected by a user. As shown, primary outlet  110  is connected with line  68 . A retaining nut  120  ( FIG. 2 ) helps secure diverter valve  100  to countertop  54  and a seal  118  ( FIG. 2 ) can be used to prevent fluids on the surface  56  of countertop  54  from leaking below countertop  54 . 
         [0021]    In addition, the present invention allows exemplary diverter valve  100  to provide an air-gap or break feature to help prevent fluid backflow. For example, the filtered water line  62  may represent a filtered water supply provided by a reverse osmosis unit. Such units typically create a reject or concentrate flow of water that carries away contaminants or other undesirable substances filtered out of the water to create a permeate or filtered water supply  62 . Accordingly, line  64  provides for a flow of reject water or reject fluid that is fed through diverter valve  100  by connection to a secondary inlet  112 . The reject fluid exits diverter valve  100  by a secondary outlet  114  to line  66  that, in turn, provides the reject fluid to drain  70  for delivery to sewage  72 . As will be understood by one of skill in the art, lines  58 ,  60 ,  62 ,  64 ,  68 ,  60 , and  72  represent e.g., piping, tubing, or other means for fluid flow. 
         [0022]    To prevent a backflow or siphoning that could cause sewage to backflow from sewage  72  and ultimately back into line  62  to potentially contaminate the filtering system, diverter valve  100  provides the additional functionality of an air gap or air break. The gap is in communication with the ambient—i.e., with the atmosphere surrounding valve  100 —to prevent a vacuum, low pressure, or other conditions conducive to a backflow from sewage  72 . A more detailed description of the construction and operation of exemplary valve  100  will now be provided. 
         [0023]    Referring now to  FIGS. 1 and 2 , diverter valve  100  includes a display manifold  104  that contacts top surface  56  of countertop  54 . Indicia  116  provided on handle  102  can be used to visually denote the position or state of valve  100 . A variety of connection types may be used to connect valve  100  with the various lines—i.e., pipes and/or tubing depicted in  FIG. 1 . For this exemplary embodiment, diverter valve  100  is equipped with quick disconnect type connectors  124 ,  125 , and  127  ( FIGS. 5 and 6 ) for first primary inlet  106 , second primary inlet  108 , and primary outlet  110 , respectively. Ribbed connectors  126  and  128  are provided for secondary inlet  112  and secondary outlet  114 , respectively. However, these connectors are each provided by way of example only and other connection types may be used. 
         [0024]    Referring now to  FIGS. 3 and 4 , diverter valve  100  includes a cylindrically-shaped main body  122  that includes first primary inlet  106 , second primary inlet  108 , primary outlet  110 , secondary inlet  112 , and secondary outlet  114 . As used herein, “primary” refers to flow manipulated by the user while “secondary” refers to flow for which backflow prevention is provided. Main body  122  also includes a secondary fluid channel  152  that connects the secondary inlet  112  with the secondary outlet  114 . 
         [0025]    More particularly, secondary fluid channel  152  includes a first portion  152   a  and a second portion  152   b  connected by an air break or air gap  136 . Main body  122  extends longitudinally along a vertical axis A-A between an upper end  160  and a lower end  162 . Gap  136  is positioned near the upper end  160  while secondary inlet  112  and secondary outlet  114  are positioned near the lower end  162 . Thus, gap  136  is elevated along vertical axis A-A- relative to secondary inlet  112  and secondary outlet  114 , which are positioned below gap  136 . For this exemplary embodiment, first portion  152   a  and second portion  152   b  of secondary fluid channel  152  each extend through main body  122  in a substantially parallel manner to vertical axis A-A. 
         [0026]    Gap  136  is communication with—i.e., connected with—the ambient that is exterior to diverter valve  100 . Continuing with  FIGS. 3 and 4 , diverter valve  100  includes a rotatable valve element  132  received within main body  122 . Valve element  132  includes a valve stem  134  that extends through gap  136  and a display retaining nut  130 , which is used to help secure display manifold  104  and diverter valve  100  to countertop  54 . The tolerance between valve stem  134  and display retaining nut  130  provides a small opening  158  through which gap  136  is in communication with the ambient exterior to diverter valve  100 . A similar opening can be provided through threads  164  where display retaining nut  130  is connected into the upper end  160  of main body  122 . At the same time, the tolerance is sufficient to prevent low pressure fluid flow through secondary fluid channel  152  from leaking. 
         [0027]    Accordingly, fluid can travel into secondary fluid inlet  112  (flow arrow SI), move upward vertically along first portion  152   a  of fluid channel  152  (flow arrow U), and into gap  136 . From gap  136 , fluid can travel downward vertically through second portion  152   b  of fluid channel  152  (flow arrow D) and exit diverter valve  100  through secondary outlet  114  (flow arrow SO). Because gap  136  is continuously in fluid communication with the ambient, gap  136  helps prevent the formation of a vacuum or other conditions that could lead to a backflow through line  66  from sewage  72 . For this exemplary embodiment, gap  136  is formed between a plug  138  received into main body  122  and display retaining nut  130 . However, other constructions may be used to provide gap  136  along the secondary fluid channel  152 . 
         [0028]    At the same time, diverter valve  100  provides additional functionality in allowing a user to control or select fluid flow through valve  100 . Referring now to  FIGS. 5 and 6 , stem  134  at a top end of rotatable valve element  132  passes through an opening  156  in plug  138  and through nut  130  to connect with dial or handle  102 . At the other end, rotatable valve element  132  includes a ball  148  defining a groove or slot  150 . Thus, the rotation of handle  102  also rotates valve element  132  to control the orientation of slot  150 . 
         [0029]    Accordingly, in  FIG. 6 , valve element  132  has been selectively rotated into a first position placing the first primary inlet  106  into fluid communication with the primary outlet  110 . As such, unfiltered fluid may flow in through first primary inlet  106  (flow arrow FPI), pass through primary fluid channel  154  defined by main body  122 , and exit through primary outlet  110  to travel to faucet  52  though line  68  ( FIG. 1 ). 
         [0030]    In  FIG. 5 , valve element  132  has been selectively rotated into a second position that disconnects the first primary inlet  106  from fluid communication with the primary outlet  110 . For this exemplary embodiment of valve  100 , in the second position, the second primary inlet  108  is placed into fluid communication with the primary outlet  110 . As such, filtered fluid may flow into valve  100  through second primary inlet  108  (flow arrow SPI), pass through primary fluid channel  154 , and exit valve  100  through primary outlet  110  to travel to faucet  52  though line  68  ( FIG. 1 ). In an alternative embodiment of the present invention, the second position would simply disconnect the first fluid inlet  106  and the primary outlet  110 , and valve element  132  is rotatable between such positions. Other configurations may be used as well. 
         [0031]    Referring now to  FIG. 3 , valve element  132  defines a plurality of grooves  140  and  144  equipped with o-rings or seals  142  and  146 , respectively, to prevent fluid from primary fluid channel  154  from leaking into other parts of valve  100 . However, the present invention is not limited to the particular shape or configuration of valve element  132  and others may be used as well. 
         [0032]    This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.