Patent Publication Number: US-2023140314-A1

Title: Reversible spring retention assembly for a valve

Description:
CROSS-REFERENCE 
     This application is a division of and claims the benefit of U.S. patent application Ser. No. 17/402,737 entitled BACKFLOW PREVENTION ASSEMBLY WITH TELESCOPING BIAS ASSEMBLY AND REVERSIBLE VALVE MEMBER, filed on Aug. 16, 2021, which claims priority to U.S. Provisional Patent Application No. 63/066,411 entitled BACKFLOW PREVENTION ASSEMBLY WITH TELESCOPING BIAS ASSEMBLY AND REVERSIBLE VALVE MEMBER, filed Aug. 17, 2020 under 55 U.S.C. § 119(e), each of which is incorporated herein by reference in its entirety and for all purposes. 
    
    
     FIELD OF THE DISCLOSURE 
     The subject disclosure relates to backflow prevention valves and assemblies, and more particularly to backflow prevention valves and assemblies having a reversible telescoping bias spring retention assembly coupled to a reversible valve member. 
     BACKGROUND 
     In many water systems, backflow prevention (BFP) assemblies allow fluid and even solids to flow only in a desired, i.e., a forward, direction. As backsiphonage or backflow can present contamination and health problems, the backflow prevention valves and assemblies prevent flow in an undesired direction, i.e., a backward or reverse direction. BFP assemblies are installed in buildings, such as residential homes, and commercial buildings and factories, to protect public water supplies by preventing the reverse flow of water from the buildings back into the public water supply. 
     A typical BFP assembly includes an inlet shutoff valve and an outlet shutoff valve with a backflow prevention valve assembly extending between the inlet and outlet shutoff valves. Many different configurations of BFP assemblies are commercially available, each being differently configured. 
     Owing to the fact that BFP assemblies are important for water safety, BFP units are tested annually, often per government regulations, to assure proper operating condition. Specifically, fluid pressure measurements are taken at specified locations in the BFP unit. If it is determined that a check valve needs to be repaired or replaced, the inlet and outlet shutoff valves have to be closed, the check valve fixed and tested, the shutoff valves opened and the apparatus confirmed to be operating per any required ordinances and/or standards. The process is time-consuming and the steps have to be performed in the correct sequence and manner in order to not contaminate the public water supply, inadvertently flood an area, and return the BFP assembly to working order. 
     SUMMARY 
     From time to time, various components of a BFP assembly may need replacement, which is not only difficult and time consuming but results in downtime for the fluid network. Components for the BFP assembly that are easier to manufacture, assemble and install as well as more robust would reduce: the difficulty of fabrication and repair; repair time; assembly error from improper fabrication or otherwise; and the difficulty of installation. Preferably, a telescoping spring retainer assembly provides some or all of these benefits along with reducing the required components. When the telescoping spring retainer assembly is coupled to a reversible valve member, these benefits are further enhanced. 
     The subject technology is directed to a valve assembly including a spring retention assembly coupled to a valve member. The spring retention assembly has an elongated cylinder portion having an open threaded end and a closed end. An elongated piston portion has a free end and a threaded tab end configured to thread through the open threaded end and, thereby, be slideably captured in the cylinder portion. A spring couples to the body portion and the piston portion to provide a force to urge the body portion and the piston away from one another, wherein the closed end and the free end are similarly shaped so that the spring retention assembly can be reversibly mounted. A valve member includes a central disc having a first side and a second side, each side forming a sealing region and having a retention cup, wherein both retention cups can capture the closed end or the free end so that the valve member is reversible. A hinge portion extends radially from the central disc. 
     In one embodiment, the subject disclosure is directed to a spring retention assembly for a valve assembly, comprising an elongated cylinder portion having an open threaded end and a closed end. An elongated piston portion has a free end and a threaded tab end configured to thread through the open threaded end and, thereby, be slideably captured in the cylinder portion. A helical spring couples to the body portion and the piston portion to provide a three to urge the body portion and the piston away from one another, wherein the closed end and the free end are similarly shaped so that the spring retention assembly can be reversibly mounted. 
     In another embodiment, the subject disclosure is directed to a spring retention assembly for a valve assembly having a cylinder portion with an open threaded end. A piston portion has a threaded tab end configured to thread through the open threaded end and, thereby, be captured in the cylinder portion for sliding motion. A spring couples to the body portion and the piston portion to provide a force to urge the body portion and the piston away from one another. Preferably, the cylinder portion has a closed end. with a retention collar, the piston portion has a retention collar, and the spring extends between the retention collars. The spring may be under a predetermined amount of compression less than an amount of force of a normal forward flow of fluid in the backflow prevention system. The inner diameter of the cylinder portion and an outer diameter of the threaded tab end can be approximately equal so that lateral movement of the piston portion is reduced. 
     In still another embodiment, the subject disclosure is directed to a spring retention assembly for a valve assembly that includes a telescoping central portion with a first free end and a second free end, wherein the ends are similarly shaped so that the spring retention assembly can be reversibly mounted. Preferably, the ends are bulbous to fit in a hollow formed in the housing of the valve assembly or a retention cup of the valve element. Another embodiment includes a first retention collar on the first free end, a second retention collar on the second free end, and a spring extending between the retention collars so that the ends are configured to mount to either retention collar for simplification of the parts required. 
     The subject technology is also directed to a valve member for a valve assembly including a central disc having a first side and a second side, each side forming a sealing region and having a retention cup, wherein the sealing regions and the retention cups are similarly shaped so that the valve member is reversible. A hinge portion extends radially from the central disc. The sealing regions may be ring-shaped elastomeric inserts. Preferably, the retention cups are centrally located on the respective side with a plurality of deflectable fingers for receiving a spherical end of a spring retention assembly. By being the same shape and size, the deflectable fingers facilitate either side interacting with the spring retention assembly. By the first and second sides being symmetrical about an axis, reversibility of the valve member is also facilitated. In one embodiment, the hinge portion includes a pair of opposing arms extending radially from the central disc and having distal protruding tabs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects of the present disclosure are discussed herein with reference to the accompanying Figures. It will be appreciated that for simplicity and clarity of illustration, elements shown in the drawings have not necessarily been drawn accurately or to scale. For example, the dimensions of some of the elements can be exaggerated relative to other elements for clarity or several physical components can be included in one functional block or element. Further, where considered appropriate, reference numerals can be repeated among the drawings to indicate corresponding or analogous elements. For purposes of clarity, however, not every component can be labeled in every drawing. The Figures are provided for the purposes of illustration and explanation and are not intended as a definition of the limits of the disclosure. 
         FIG.  1    is a cross-sectional view of a backflow prevention BFP assembly with only the second check valve assembly open in accordance with the present disclosure. 
         FIG.  2    is a cross-sectional view of the BFP assembly of  FIG.  1    with both check valve assemblies closed in accordance with the present disclosure. 
         FIG.  3    is perspective view of a telescoping spring retainer assembly in an extended position for a check valve assembly for a BFP assembly in accordance with the present disclosure. 
         FIG.  4    is a plan view of the telescoping spring retainer assembly of  FIG.  3   . 
         FIG.  5    is a cross-sectional view of the telescoping spring retainer assembly taken along line  5 - 5  of  FIG.  4   . 
         FIG.  6    is a partial detailed cross-section view of the telescoping spring retainer assembly shown in circle  6  of  FIG.  5   . 
         FIG.  7    is a perspective view of the telescoping spring retainer assembly of  FIG.  3    in a compressed position. 
         FIG.  8    is a plan view of the telescoping spring retainer assembly of  FIG.  7   . 
         FIG.  9    is a cross-sectional view of the telescoping spring retainer assembly taken along line  9 - 9  of  FIG.  8   . 
         FIG.  10    is a partial detailed cross-section view of the telescoping spring retainer assembly shown in circle  10  of  FIG.  9   . 
         FIG.  11 A  is an isolated side view of a frame for use in a check valve assembly in accordance with the subject disclosure. 
         FIG.  11 B  is an isolated perspective view of a frame for use in a check valve assembly in accordance with the subject disclosure. 
         FIG.  12    is a partial cross-sectional view of a reversible valve member coupled to a frame in a check valve assembly in accordance with the subject disclosure. 
         FIG.  13 A  is an isolated perspective view of another reversible valve element for use in a check valve assembly in accordance with the subject disclosure. 
         FIG.  13 B  is a cross-sectional view of the reversible valve member of  FIG.  13 A . 
         FIG.  14    is an isolated perspective view of a telescoping spring retention assembly coupled to a reversible valve member for use in a check valve assembly in accordance with the subject disclosure. 
         FIG.  15    is perspective exploded view of another telescoping spring retainer assembly for a check valve assembly for a BFP assembly in accordance with the present disclosure. 
         FIG.  16    is a side view of the telescoping spring retainer assembly of  FIG.  15    with the spring removed. 
         FIG.  17    is another side view of the telescoping spring retainer assembly of  FIG.  15   . 
         FIG.  18    is a partial perspective view of the cylinder portion of the telescoping spring retainer assembly of  FIG.  15   . 
     
    
    
     DETAILED DESCRIPTION 
     The subject technology overcomes many of the prior art problems associated with backflow prevention assemblies. The advantages, and other features of the technology disclosed herein, will become more readily apparent to those having ordinary skill in the art from the following detailed description of certain exemplary embodiments taken in combination with the drawings and wherein like reference numerals identify similar structural elements. It should be noted that directional indications such as vertical, horizontal, upward, downward, right, left and the like, are used with respect to the figures and not meant in a limiting manner. 
     Referring now to  FIGS.  1  and  2   , there is shown a backflow prevention (BFP) assembly  100  in accordance with an aspect of the present disclosure. The BFP assembly  100  may be installed in a fluid system, e.g., a water supply for a building. In normal operation, the backflow prevention assembly  100  operates to carry fluid in only a forward direction, e.g., left to right in  FIGS.  1  and  2   , from an inlet  116  to an outlet  120 . The BFP assembly  100  operates to prevent flow in a backward direction, i.e., a direction from right to left in  FIGS.  1  and  2   . 
     The BFP assembly  100  includes a body  104  forming an upstream bucket  108  and a downstream bucket  112 . Each bucket  108 ,  112  is enclosed by a test cover  118 ,  122 . The test covers  118 ,  122  may include one or more test cocks  140  for sensing pressure at various locations within the BFP assembly  100 . The downstream test cover  118  includes two test cocks  140  and the upstream test cover  122  includes a single test cock  140  but the test covers  118 ,  122  are otherwise very similar. 
     Each bucket  108 ,  112  includes a check valve assembly  150  for selectively opening and closing flow through the respective bucket  108 ,  112 . Preferably, the check valve assemblies  150  are interchangeable although as shown, the check valve assemblies  150  are different. Each check valve assembly  150  has frame  170  fit into the respective bucket  108 ,  112 . The frame  170  retains a valve member  200 , which selectively closes against a circular valve seat  172  of the frame  170 . The valve members  200  are generally disc-shaped with an annular sealing region  204  that seals against the valve seat  170 . The valve member  200  is connected to the frame  170  by a hinge portion  206  that allows rotation of the valve member  200  away from the valve seat  172  to open flow. 
     In each check valve assembly  150 , a spring retainer assembly  300  provides a biasing force to urge the valve member  200  against the valve seat  172 . If the pressure downstream of the valve member  200  exceeds the force of the spring retainer assembly  300 , the check valve assembly  150  will open to allow forward flow. If not, the spring retainer assembly  300  will keep the check valve assembly  150  closed. The spring retainer assembly  300  extends between the respective test cover  118 ,  122  and the valve member  200 . The test covers  118 ,  122  form hollows  124  for coupling to the spring retainer assembly  300  whereas the valve member  200  has a retention cup  210  for coupling to the spring retainer assembly  300 . 
     Referring now to  FIGS.  3 - 10   , various views of the spring retainer assembly  300  are shown. The spring retainer assembly  300  includes a telescoping central portion  302 . The telescoping central portion  302  includes a somewhat tubular cylinder portion  310  with an open lip end  312 . The open lip end  312  has internal threads  314  best seen in  FIGS.  6  and  10   . A closed free end  316  opposes the open lip end  312  and has a spherical or bulbous shape for coupling to the retention cup  210  of the valve member  200  or in the hollow  124  of the test cover  118 ,  122 , as the case may be. Adjacent the bulbous closed free end  316 , a retention collar  318  is formed. 
     The spring retainer assembly  300  also includes a piston portion  330  that partially slides within the cylinder portion  310 . The piston portion  330  has a tab end  332  that is captured within the cylinder portion  310 . The tab end  332  has outer threads  334 . To couple the cylinder portion  310  and the piston portion  330  together, the tab end  332  is threaded through the open lip end  312  of the cylinder portion  310 . Once coupled, the tab end  332  can slide within the cylinder portion  310  but is retained by the lip end  312  until unscrewed. 
     The piston portion  330  has a free end  336  with a retention collar  338 . A spring  350  is captured and compressed between the retention collars  318 ,  338  to urge the cylinder portion  310  and piston portion  330  apart as best seen in  FIGS.  3 - 5   . Thus, when in the spring retainer assembly  300  is in place between the fixed rigid hollow  124  of a test cover  118 ,  122  and retention cup  210  of the valve element  200 , the spring  350  provides the biasing force to urge the valve element  200  closed (see  FIGS.  1  and  2   ). 
     As illustrated in  FIGS.  7 - 10    and shown in the downstream check valve assembly  150  of  FIG.  2   , the spring retainer assembly  300  is compressed by opening of the check valve assembly  150  when the upstream pressure on the valve member  200  exceeds the force provided by the spring  350 . In other words, the force of the spring  350  is predetermined to allow the valve element  200  to permit the normal flow of fluid in the forward direction. 
     In order to minimize wobbling or lateral motion of the piston portion  330  during sliding, an inner diameter D 1  of the cylinder portion  310  is approximately the same as the outer diameter D 2  of the threaded tab end  332  (see  FIG.  6   ). The threaded tab end  332  also has sufficient length along the axis of movement to be stable inside the cylinder portion  310 . In this way, the piston portion  330  moves linearly and is prevented from wobbling. The length of the threaded tab end  332  and cylinder portion  310  are selected to minimize wobbling while still allowing sufficient travel for a fully open and closed check valve  150 . 
     In normal operation, the force exerted by the respective spring retainer assembly  300  on the valve elements  200  is overcome by the pressure exerted by the fluid normally flowing from the inlet  116  to the outlet  120  so that both check valves  150  are open. If, for example, there is a drop in pressure from the supply source, the upstream valve element  200  and the downstream valve  200  will close to prevent backflow as shown in  FIG.  2   . Similarly, if the normal forward flow is interrupted, one or both of the valve elements  200  is urged in position to cover the valve seat  172  (e.g.,  FIGS.  1  and  2   , respectively) to close the check valve  150  and prevent backflow. 
     To assemble a check valve  150 , the threaded tab end  332  of the piston portion  330  is screwed through the threaded lip end  312  of the cylinder portion  310  to couple the piston portion  330  to the cylinder portion  310 . Either end  316 ,  336  may be coupled to the retention cup  210  of the valve element  200  because each end  316 ,  336  is similarly shaped. Preferably, the retention cup  210  is flexible and deforms slightly to receive the spherical end  316 ,  336  without requiring any tools. Once popped in, the bulbous end  316 ,  336  easily rotates within the retention cup  210 . As the test cover  118  is mounted is mounted on the check valve  150 , the other end  316 ,  336  of the spring retention assembly  300  is aligned to the hollow  124 , which captures the end  316 ,  336  while also allowing for easy rotation of the end  316 ,  336  therein. Thus, the spring retention assembly  300  can be arranged in a reverse arrangement to that which is shown and assembly is simplified. 
     Repair of the spring retention assembly  300  is also simplified. For example, if the piston portion  330  is broken, the threaded tab end  332  is unthreaded from the cylinder portion  310 . To replace the broken piston portion  330 , a new piston portion  330  can be threaded into the previously used cylinder portion  310 . Similarly, without tools, the portions  310 ,  330  can be separated to replace the helical spring  350 . 
     In one embodiment, the ends  316 ,  318  include a spherical portion  319  having a threaded post  321  that screws into or otherwise mounts to the retention collar  318 ,  338 . Hence, the threaded posts  312  are the same so that fewer parts are required and manufacturing and repair is simplified. Further, as tools are not required, assembly is simplified. In another embodiment, the ends  316 ,  318  are different sizes to preclude reversibility. For example, only one end  316 ,  318  may be small enough to fit into the retention cup  210  so that there is only one orientation that couples the spring retention assembly  300  to the valve element  200 . 
     In another embodiment, the spring retention assembly does not include a helical spring around the outside. Instead, the helical spring or even a compressible insert is provided with the cylinder portion to generate the proper bias. 
     Referring now to  FIGS.  11 A and  11 B , isolated side and perspective views of a frame  170  for use in a check valve assembly in accordance with the subject disclosure are shown. The frame  170  snugly fits into the respective bucket. A top portion  174  seals against the BFP assembly body and a lower portion  177  narrows the fluid path through the BFP assembly to an opening  175  of the valve seat  172 . The top portion  174  includes a circular ledge  182  that acts as an insertion hardstop. A retaining nut  126  (see  FIG.  1   ) threads onto the body  104  to secure the frame  170  thereto. The valve seat  172  also includes an annular raised rim  176  as a sealing surface with a recess  178  surrounding the rim  176 . 
     The frame  170  includes standoff  179  adjacent the opening  175  and forming a pair of opposing notches  180 . The notches  180  may be U-shaped to receive a valve member such that the valve member is hinged to the frame  170  for selective opening and closing of the opening  175 . The notches  180  may also simply be holes or similar shape to receive a protruding tab to create a hinge arrangement. 
     Referring now to  FIG.  12   , a partial cross-sectional view of a reversible valve member  400  coupled to a frame  450  in a check valve assembly of a BFP assembly in accordance with the subject disclosure is shown. Like reference numerals in the “400” series are used to refer to similar elements between the frame  170  and the frame  470 . Similarly “400” series numbers are also used to describe like elements between the valve members  200 ,  400  so that the following description can be directed to the differences. 
     The valve member  400  is reversible by being symmetrical. The valve member  400  has a central disc  402 . Each side of the central disc  402  has a central retention cup  410 . The cups  410  have a plurality of fingers  412  that deflect to allow manual insertion of the end  316  of the spring retention assembly  300  to capture the end  316  therein. Once captured, the end  316  can smoothly rotate within the cup  410  like a ball-and-socket joint. Similar connections like a condyloid joint, saddle joint, hinge joint, pivot joint and the like may be used. The valve member  400  also has a radially outward ring-shaped sealing region  404  on each side  408 . An outer edge  414  of the central disc  402  may be relatively thicker than the sealing region  404 . The hinge portion  406  extends from the outer edge  414  of the central disc  402 . In one embodiment, the sealing surface  476  is a ring-shaped elastomeric insert on each side  408 . 
     Once assembled, as shown in the closed position in  FIG.  12   , the spring retention assembly  300  urges the valve member  400  against the valve seat  472 . The sealing region  404  of the valve member  400  and the sealing surface  476  of the frame seat  172  are sealingly engaged to close the opening  475 . When the upstream fluid pressure exceeds the urging force of the spring retention assembly  300 , the valve member  400  rotates to open the opening  475  and, in turn, the end  316  rotates within the deflectable fingers  412  of the retention cup  410 . 
     By being symmetrical, the valve member  400  can be arranged in a reverse arrangement and work in the same manner. Thus, assembly is simplified. Further, repair of the valve member  400  is also simplified. For example, if the valve member  400  is broken on one side in the field, rather than locate a replacement part, the valve member  400  can be unhinged, flipped and rehinged. As a result, the required number of parts is reduced with assembly and repair simplified. Preferably, tools are also not required. 
     Referring now to  FIGS.  13 A and  13 B , isolated views of another reversible valve member  500  for use in a check valve assembly in accordance with the subject disclosure are shown. As will be appreciated by those of ordinary skill in the pertinent art, the valve member  500  utilizes similar principles to the valve members  200 ,  400  described above. Accordingly, like reference numerals in the “500” series are used to indicate like elements. 
     The primary difference of the valve member  500  is the sloped sealing region  504  as best seen in  FIG.  13 B . The sloped sealing region  504  may be formed by partially fully coating the central disc  502 . Alternatively, the entire central disc  502  may be formed from an elastomeric or other material with the desired sealing properties. The valve member  500  is still symmetrical about an axis of symmetry “a” for reversibility. 
     The hinge portion  506  includes a pair of opposing radially extending flexible arms  507 . The arms  507  have distal tabs  509  protruding outward to engage the frame. By manually deflecting the arms  507  inward (e.g, closer together), the tabs  509  can be snap-fit into the notches of the frame. In another embodiment, the hinge portion and the standoff of the frame have transverse passages for receiving a hinge pin to create the hinge. It is envisioned that the tabs  509  may simply rest in the notches with the force of the spring assembly being sufficient so that the tabs  509  float in place to allow easy freedom of movement. 
     Referring now to  FIG.  14   , an isolated perspective view of the telescoping spring retention assembly  300  coupled to the reversible valve member  500  in accordance with the subject disclosure is shown. Again, if the valve member  500  becomes damaged in the field (e.g., one of the cups  512  become broken), the valve member  500  can simply be flipped and reinstalled without tools in the check valve assembly. Similarly, the orientation of the valve member  500  and spring retention assembly during initial assembly is not important, which makes assembly easier. 
     Referring now to  FIGS.  15 - 18   , various views of another spring retainer assembly  600  are shown. Similar elements to those described in connection with above-described embodiments are indicated with the like reference numbers in the “600” series. Many elements are essentially the same as those of the foregoing embodiments and, thus, are not further described herein. Thus, the following description relates to the differences of the spring retainer assembly  600 . 
     The spring retainer assembly  600  has a piston portion  630  with opposing buttons  611  near the end  632  for coupling to the cylinder portion  610 . The cylinder portion  610  forms opposing two-part slots  613  that capture the buttons  611  to guide the telescoping motion. Each two-part slot  613  has a cross-wise portion  615  and an axial portion  617 . During normal operation, the buttons  611  are captured in the axial portion  617  of the two-part slots  613  to guide linear motion and prevent the spring retainer assembly  600  from coming apart if the test cover is opened or removed. As shown in  FIG.  17   , the spring retainer assembly  600  is fully extended. 
     To assembly the spring retainer assembly  600 , the piston portion  630  is pressed into the cylinder portion  610 . The cylinder portion  610  has angled internal ramps  623  that guide the buttons  611  into axial grooves  625 . The axial grooves  625  guide the buttons  611  in the cross-wise portion  615  of the two-part slot  613  ( FIG.  16   ). Once the buttons  611  are in the slot  613 , the piston portion  630  can be rotated along arrow  627  as shown in  FIG.  18    to be in the operational position within the axial portion  617  of the slot  613 . In another embodiment, the buttons  611  are push-buttons that retract during insertion into the slot  613 . In still another embodiment, the slot  613  extends toward the open end (e.g., along the line of the groove  625 ). The cylinder portion  610  may also be somewhat deformable so that the cylinder portion  610  can be flexed to insert the buttons  611  in the slots. 
     As can be seen, the subject disclosure provides many improvements to BFP assemblies  100 . For example, without limitation, the BFP assemblies  100  are more easily manufactured by simplification and/or reversibility of components. The assembly is not only easier but more error proof due to improved design of components. Similarly, repair is also faster, easier and less complex. Further, the subject technology can be adapted to any kind of valve. 
     It will be appreciated by those of ordinary skill in the pertinent art that the functions of several elements can, in alternative embodiments, be carried out by fewer elements, or a single element. Similarly, in some embodiments, any functional element can perform fewer, or different, operations than those described with respect to the illustrated embodiment. Also, functional elements (e.g., check valves, valve elements, spring retention assemblies, and the like) shown as distinct for purposes of illustration can be incorporated within other functional elements in a particular implementation. 
     While the subject technology has been described with respect to various embodiments, those skilled in the art will readily appreciate that various changes and/or modifications can be made to the subject technology without departing from the scope of the present disclosure.