Abstract:
A bypass valve has a body with an inlet for receiving untreated water, an untreated water outlet for connection to a water treatment apparatus, a treated water inlet and an outlet through which treated water flows. The body includes a first valve seat between the inlet and the outlet, a second valve seat between the treated water inlet and the outlet, and a third valve seat in a flow path between the inlet and the outlet. A set of first, second and third flapper valve elements selectively engage and disengage the first, second and third valve seats respectively. The three flapper valve elements are preferably connected to a common manually operable actuator which can be latched to hold the valve elements in different functional positions.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Not applicable. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to water treatment systems, and more particularly to bypass valves for disconnecting the treatment apparatus of such a system from building plumbing connections. 
   2. Description of the Related Art 
   A water treatment system, such as a water softener or reverse osmosis filter, often is incorporated into the plumbing of a building. For example, potable water received from a well usually is considered to be “hard” as containing minerals that adversely affect the cleansing ability of soaps and detergents. Furthermore, the minerals leave objectionable deposits on plumbing fixtures, glassware and the like. As a consequence, a water softener or filter is employed to remove the minerals and “soften” the water. 
   Occasionally, it is necessary to perform maintenance on the water treatment system, such as replacing the filter medium or a failed component. In order to perform such maintenance, the water treatment apparatus must be functionally and sometimes physically disconnected from the building&#39;s plumbing system. However, while the maintenance is being performed, it is desirable to provide untreated water for use in the building for drinking, flushing toilets and other purposes. Therefore, a bypass valve is provided at the connection of the water treatment apparatus to the building plumbing system. The bypass valve disconnects both the inlet and the outlet of the treatment apparatus from the plumbing pipes and interconnects those pipes so that water is provided throughout the building while the maintenance is being performed. 
   Because a bypass valve is operated infrequently, the seals become stuck to the movable components making it difficult to operate the valve. In fact considerable force may be required to “break” the stuck seal. The exertion of the force necessary to operate the valve can damage the seal to the point that when the valve was later restored to the operating position, water leaked past the seal. 
   Therefore, it is desirable to provide a bypass valve which does not exhibit such seal sticking. 
   SUMMARY OF THE INVENTION 
   A bypass valve for a water treatment system comprises a body that has an inlet for receiving untreated water, an untreated water outlet, a treated water inlet, and an outlet through which treated water flows. The body includes a first valve seat between the inlet and the outlet, a second valve seat between the treated water inlet and the outlet, and a third valve seat in a flow path between the inlet and the outlet. A first flapper valve element is movable with respect to the body to selectively engage and disengage the first valve seat. A second flapper valve element is movable with respect to the body to selectively engage and disengage the second valve seat. A third flapper valve element is movable with respect to the body to selectively engage and disengage the third valve seat. 
   Preferably the body has aligned first, second, and third valve openings for receiving the first, second and third flapper valve elements in a manner that allows the valve elements to pivot in the openings. In this preferred embodiment, the three flapper valve elements are connected to a common manually operable actuator which can be latched to hold the valve elements in different functional positions. 
   In another aspect of the present bypass valve, each of the first, second and third flapper valve elements comprises a plate, a resilient valve seal attached to a section of the plate and adapted to engage a valve seat, and a flange of resilient material projecting outwardly from the plate to provide a water tight seal with the body. 

   
     DESCRIPTION OF THE OF THE DRAWINGS 
       FIG. 1  is an isometric view of the rear of a bypass valve according to the present invention; 
       FIG. 2  is an isometric view of the front of the bypass valve; 
       FIG. 3  is an exploded view of the bypass valve; 
       FIG. 4  is a cross sectional view through a valve element used in the bypass valve; 
       FIG. 5  is a horizontal cross-sectional view through the bypass valve; 
       FIG. 6  is a cross-sectional view taken along the line  6 - 6  of  FIG. 5 ; and 
       FIG. 7  is a cross-sectional view taken along lines  7 - 7  of  FIG. 5 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   With initial reference to  FIG. 1 , a bypass valve  10  has a body  12  with an inlet  14 , which is adapted to be connected to a pipe of a building plumbing system that supplies water to a water treatment apparatus, and an outlet  16  through which treated water returns to the plumbing system. A drain outlet  18  is provided to connect the bypass valve to a waste pipe or drain opening in the building. The body  12  also has a valve actuator, in the form of a bar  20 , by which a user operates the bypass valve  10 . 
   Referring to  FIG. 2 , the front side of the bypass valve  10  has an untreated water outlet  22  through which water flows out the bypass valve to a water treatment apparatus. A treated water inlet  24  is provided for connection to the water treatment apparatus to receive water therefrom. 
     FIG. 3  is an exploded view illustrating the components of the bypass valve  10 . The body  12  comprises a manifold  26  that contains the inlet  14 , the outlet  16 , the untreated water outlet  22 , and the treated water inlet  24 . The manifold  26  has an open bottom that- is closed by a base  28  which is secured to the manifold by a suitable means. For example, the manifold  26  and base  28  are molded plastic pieces which are welded or cemented together. As shown in  FIG. 3 , the base  28  includes a drain inlet  25  on an opposite side from the drain outlet  18  with the drain inlet being adapted to couple to a drain port on the water treatment apparatus. A tubular portion  27  of the base  28  directly connects the drain inlet  25  to the drain outlet  18  thereby providing a through path for drain water to flow through the bypass valve  10 . The body  12  also has a plug  30  that closes an opening in the manifold  26  (see  FIG. 1 ) that is required by the molding process. The upper surface  32  of the manifold  26  has three valve apertures  34 ,  35  and  36  extending into chambers within the manifold, as will be described. 
   A separate flapper valve element  38 ,  40  and  42  is received in each valve aperture  34 ,  35  and  36 , respectively. The three flapper valve elements  38 ,  40  and  42  are identical with the details of the first one  38  being shown in  FIG. 4 . The first flapper valve element  38  has a rigid metal plate  44  with a lower section, over which a rubber valve seal  46  is molded, and with an exposed upper section forming a stem  52 . The valve seal  46  comprises a sealing section  48  which engages valve seats in the manifold  26  to close communication between different chambers of that manifold, as will be described. The valve seal  46  also has a flange  50  projecting outwardly from all sides of the metal plate  44 . 
   Referring again to  FIG. 3 , each of the valve apertures  34 ,  35  and  36  is countersunk to provide a recess there around for receiving the flange  50  of the respective flapper valve element  38 ,  40  or  42 . The stem  52  of those valve elements  38 ,  40  and  42  project through openings  54 ,  55  and  56  in a valve retainer  57  that extends over and is secured to the upper surface of the manifold  26 . The valve retainer  57  holds the valve element flanges in the respective manifold opening in a manner that provides a fluid type seal while allowing the flapper valve element to pivot. 
   The actuator bar  20  has a generally planar design with openings on its lower edge within which the stems  52  of the valve elements  38 ,  40  and  42  are received ( FIGS. 1 and 2 ). Thus, pivoting the actuator bar  20  with respect to the valve retainer  57  produces a similar simultaneous motion of all three the valve elements. A first locking groove  58  extends along the lower or proximate, edge of the actuator bar  20  and is adapted to receive a latch  61  when the valve actuator is perpendicular to the valve retainer  57 , as illustrated. The latch  61  is a C-shaped rod with ends received in notches on opposite sides of the valve retainer  57 . The latch  61  is able to pivot with respect to the valve retainer  57  into another position in which it engages a second locking groove  59  extending along the upper edge of the actuator bar  20 . 
     FIG. 5  is a horizontal cross-section view through the manifold looking downward and illustrates the chambers of the manifold  26 . The inlet  14  opens into an inlet chamber  60  that is separated from the untreated water outlet  22  by first wall  62 . That first wall  62  has a first aperture  64  there through with a first valve seat  66  within the inlet chamber  60  extending around the first aperture and providing a fluid path between the inlet and the untreated water outlet  22 . The outlet  16  opens into an outlet chamber  68  that is separated by first wall  62  from the treated water inlet  24 . A second aperture  70  provides a fluid path through the first wall between the outlet chamber  68  and the treated water inlet  24 . A second valve seat  72 , within the outlet chamber  68 , extends around the second aperture  70 . An second wall  74  separates the inlet chamber  60  from the outlet chamber  68  and has a third aperture  76  around which a third valve seat  78  extends within the inlet chamber  60  to provide a fluid path between the inlet and the untreated water outlet. 
   With reference to  FIGS. 5 and 6 , the bypass valve  10  is illustrated in the bypass state in which fluid communication is established directly between the inlet  14  and the outlet  16  via the third aperture  76  in the second wall  74 . In this state, the sealing sections  48  of the first and second flapper valve elements  38  and  40  are respectively held against the first and second valve seats  66  and  72 , closing the associated aperture  64  and  70  and flow paths through in the first wall  62 . Thus communication is blocked between the inlet  14  and the untreated water outlet  22 , and between the treated water inlet  24  and the outlet  16 . However, the third flapper valve element  42  is positioned away from the third valve seat  78  thereby opening the third aperture  76  which provides a path between the inlet chamber  60  and the outlet chamber  68 . Thus in the bypass state, water is permitted to flow directly between the inlet and outlet  14  and  16  of the bypass valve  10  while flow to and from the water treatment apparatus is blocked. 
   With further reference to  FIGS. 1 and 2 , the latch  61  in the bypass state is located against the upper surface of the valve retainer  57 . In this position, the latch  61  is received within a first locking groove  58  along the bottom, or proximate, edge of the valve actuator bar  20 . That engagement prevents movement of the actuator, thereby holding the flapper valve elements  38 ,  40 , and  42  in the bypass state. 
   Referring to  FIG. 7 , the bypass valve  10  has a service state in which the water treatment apparatus is connected to treat the water flowing into the inlet  14 . In the service state, the valve actuator bar  20  is pivoted toward the front of the valve body  12  and locked in place by engagement of a raised latch  61  into the second locking groove  59 . Now, the positions of the three flapper valve elements  38 ,  40  and  42  are reversed from that shown in  FIG. 5 . Specifically, the first and second flapper valve elements  38  and  40  are away from the first and second valve seats  66  and  72 , thereby opening communication between the inlet  14  and the untreated water outlet  22  and between the treated water inlet  24  and the outlet  16 . In addition, the sealing section  48  of the third valve element  42  is abuts the third valve seat  78  as shown in  FIG. 7 , thereby closing the third aperture  76  and fluid communication between the inlet and outlet chamber  60  and  68 . 
   The foregoing description was primarily directed to a preferred embodiment of the invention. Although some attention was given to various alternatives within the scope of the invention, it is anticipated that one skilled in the art will likely realize additional alternatives that are now apparent from disclosure of embodiments of the invention. Accordingly, the scope of the invention should be determined from the following claims and not limited by the above disclosure.