Abstract:
A coupling and method are provided that include a coupler and nipple. The nipple has a valve in a normally-closed position and an outer peripheral surface with a plurality of spaced-apart, close-ended cam paths. The coupler has a valve in a normally-closed position and includes a set of latching balls for engagement with the cam paths to secure the coupler to the nipple. The coupler further includes a sleeve mounted thereon and movable between forward and retracted positions. In the forward position, the latching balls are forced into an inward position that prevents release of the latching balls from the cam paths, and in the retracted position, the latching balls are permitted to extend to an outward position enabling initial engagement with or disengagement from the cam paths. The coupler also includes a set of locking balls that prevents movement of the sleeve to the retracted position.

Description:
BACKGROUND 
       [0001]    This disclosure relates to a fluid coupling such as for use during the transfer or bulk delivery of a cryogenically controlled liquid, such as carbon dioxide, and to methods of connection to form the coupling and disconnecting of the coupling. 
         [0002]    By way of example, the beverage industry uses carbon dioxide (CO 2 ) for carbonation, and for purposes of re-supplying carbon dioxide to a large consumer, such as a restaurant, service center, or like facility, carbon dioxide is typically transported in a cryogenically controlled liquid form in a relatively large CO 2  supply tank on a delivery truck. The restaurant or like business may have a free-standing CO 2  tank located exterior of the building or may have a fill line permanently plumbed to the exterior wall of the building or like facility. For purposes of beginning a fill process, the truck operator connects a supply hose having a coupler to a fitting or nipple on an exterior tank or fill line of the facility, which may be within a lock box or the like, to thereby connect the supply tank to the fitting and enable bulk fluid delivery of carbon dioxide in liquid form to the consumer. Following the fill process, the coupler is disconnected from the nipple. 
         [0003]    Cryogenically controlled liquids, such as carbon dioxide, need to be handled with care upon transferring from the supply tank to the receiving facility. In particular, the processes of connecting and disconnecting the coupler to and from the nipple can cause problems, and safe and reliable connection and disconnection are difficult due to the extremely low temperature and high pressure of the cryogenically controlled liquid to be transferred. 
         [0004]    By way of example, while mechanical threaded connections have conventionally been used for providing such couplings or connections, various problems are encountered during connection and disconnection operations due to the low temperature, high pressure, and like characteristics of the cryogenically controlled liquid being delivered. For instance, couplings, surrounding support structures, containment boxes, and like components are often subject to damage while they become beaten as the coupler is being engaged to the nipple during connection and released from the nipple during disconnection. For instance, a rear sleeve clip or other like component can become loose on the coupler resulting in a free connection that creates a dangerous condition for the operator, especially if the coupler valve stays or sticks in an open condition thereby resulting in a hose-whip or kick-back condition. 
         [0005]    In addition, coupler valves have a tendency to remain open after disconnection due to freezing and stiction issues, and operators are typically exposed to excessively high levels of CO 2  during connection/disconnection processes. Further, seals and related components used to form seals within couplings can frequently and easily become damaged in the process. 
         [0006]    Accordingly, couplings for CO 2  and like cryogenically controlled liquid delivery systems have been problematic and unsafe. The problems encountered typically extend loading and unloading times, increase costs, and produce frequent product failures. 
         [0007]    Although problems specifically with the bulk delivery of CO 2  in the beverage industry are referenced above, these same problems can also relate to the loading, unloading, or transfer of any cryogenically controlled liquid in any industry. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is an elevational side view of a coupling including a coupler fully connected to a nipple in accordance with an embodiment. 
           [0009]      FIG. 2  is an elevational side view of the nipple of the coupling of  FIG. 1 . 
           [0010]      FIG. 3  is a perspective view of a distal end of the nipple of  FIG. 1 . 
           [0011]      FIG. 4  is a perspective view of a proximate end of the nipple of  FIG. 1 . 
           [0012]      FIG. 5  is a cross-sectional view along the length of a nipple in accordance to an embodiment. 
           [0013]      FIG. 6  is an elevational side view of the coupler of the coupling of  FIG. 1 . 
           [0014]      FIG. 7  is a perspective view of the coupler of  FIG. 1 . 
           [0015]      FIG. 8  is a cross-sectional view along the length of a coupler in accordance to an embodiment. 
           [0016]      FIG. 9  is a cross-sectional view of a coupler and nipple in a disconnected condition in accordance to an embodiment. 
           [0017]      FIG. 10  is a cross-sectional view of the coupler and nipple of  FIG. 9  upon an initial stage of engagement in accordance to an embodiment. 
           [0018]      FIG. 11  is a cross-sectional view of the coupler and nipple of  FIG. 9  upon an intermediate stage of engagement in accordance to an embodiment. 
           [0019]      FIG. 12  is a cross-sectional view of a coupler fully engaged with a nipple in accordance to an embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    According to an embodiment, a coupling is provided for use in cryogenic applications such as for the delivery of cryogenically controlled liquid carbon dioxide as discussed above. Of course, the coupling may be used for the delivery of other cryogenically controlled liquids or may be used in any other application requiring a fluid coupling and is not limited to cryogenic applications. 
         [0021]    According to an embodiment, the coupling has a locking-cam system that enables connection and disconnection procedures to be accomplished quickly with no-tools and with greatly reduced CO 2  or like undesired release and exposure to operators. This system prevents accidental disconnection of the coupling and ensures that fluid tight seals are formed in the coupling before any internal valves are urged into an open flow condition. 
         [0022]    By way of example, the coupling  10 , such as shown in  FIG. 1 , includes a coupler  12  and a nipple  14 . The nipple  14  may be connected to the terminating end of a fill line (not shown) or a free-standing storage tank (not shown) and permanently reside at the facility receiving a supply or bulk delivery of a cryogenically controlled liquid. The coupler  12  may be fastened to the end of a hose (not shown), hose fitting (not shown) or the like extending from a supply tank (not shown) on a delivery truck (not shown). 
         [0023]    As explained in greater detail below, valve operation within the coupling  10  is staged to ensure a sealed condition before the valve within the nipple  14  (i.e., the receiving side of the coupling  10 ) is urged to an open position permitting flow through the nipple. In addition, valve operation within the coupling  10  is such that a valve in the coupler  12  (i.e., the delivery side of the coupling  10 ) is urged to an open flow condition during an intermediate stage of connection before the valve in the nipple  14  is urged to an open flow condition during a final stage of connection. Conversely, the valve in the coupler  12  is returned to the normally-closed no-flow condition after the valve in the nipple  14  is returned to a normally-closed condition during disconnection. 
         [0024]    The coupling  10  simplifies the connection and disconnection processes of a delivery, requires the use of no tools during connect/disconnect processes, enables the time needed for a delivery to be reduced, and ensures that the delivery process remains safe for the operator at all times. Further, the coupling  10  minimizes the operator&#39;s exposure to the unwanted release of CO 2  or like fluid during connection and disconnection processes, and provides an improved seal and valve closure with an elastomerically energized ultra-high molecular weight (UHMW) Cup-Seal system to ensure connection longevity. The coupling  10  can be designed to compensate for a pressurized connection or residual pressure in a no-flow condition and can provide improved flow performance with reduced pressure drop. Valve/coupling stiction and freezing conditions are minimized due to the structure of the coupling and may be further minimized via the use of a PTFE impregnated nickel coating or like. 
         [0025]    Turning first to the structure of the nipple  14  (i.e., the receiving side of the coupling  10 ) shown in  FIGS. 2-5 , it includes a hollow nipple body  18  and a hollow connection adapter  20  with a valve  22 , valve guide  24  and valve spring  26  captured therebetween. 
         [0026]    The connection adapter  20  is located at the distal end of the nipple  12  (i.e., distal relative to the coupler  12 ) for direct connection, for instance, to the end of the fill line of the facility (i.e., the nipple  14  may form a permanent terminal end of the fill line on an external wall of the facility or the nipple  14  may be connected to a free-standing storage tank). The nipple body  18  may form a threaded and sealed connection with the connection adapter  20  as best shown in  FIG. 5  to provide the nipple  14  as an integral component. 
         [0027]    The valve guide  24  is held in a stationary position against an interior shoulder  28  of the connection adapter  20  with the valve  22  being guided and movable along the valve guide  24  in a longitudinal direction along the path of fluid flow within the nipple  14 . The valve spring  26  resiliently urges the valve  22  against an interior shoulder  30  of the nipple body  18  in a normally-closed position, and an elastomeric seal  32  on the valve  22  creates a normally-closed fluid-tight seal within the nipple  14  thereby preventing flow through the nipple  14 . The valve  22  of the nipple  14  remains in the normally-closed position during most stages of connection with the coupler  12  until a final stage of connection with the coupler  12  when the valve  22  is urged in an open condition as discussed in greater detail below. 
         [0028]    The nipple body  18  forms the proximal end of the nipple  14  which faces and engages the coupler  12  during connection. A plurality of separate, spaced-apart cam paths  34  in the form of generally helical grooves are formed in an outer peripheral surface  36  of the nipple body  18 . Each cam path or groove  34  has a proximal closed end  38  and an opposite distal closed end  40 . For instance, see  FIG. 2 . The proximal end  38  of each of the cam paths  34  terminates a pre-determined spaced distance from the end face  42  of the nipple body  18 . Thus, the cam paths  34  do not extend completely to and through the end face  42  of the nipple body  18  to provide a significant safety feature of the coupling  10  that prevents uncontrolled ejection of a coupler  12  (which includes a component that engages the cam paths) from the nipple  14  and ensure proper engagement between the coupler  12  and nipple  14 . The distal closed end  40  of each of the cam paths  34  may terminate in a short circumferentially-extending part of the cam paths  34  providing a detent as best shown in  FIG. 2 . 
         [0029]    Turning to the separate structure of the coupler  12  (which forms the delivering side of the coupling  10  when engaged with the nipple  14 ) shown in  FIGS. 6-8 , it includes a hollow socket body  44 , a hollow cam-engagement housing  46  connected to the socket body  44 , and a sleeve  48  carried by and movable in opposite longitudinal directions on the cam-engagement housing  46 . 
         [0030]    The socket body  44  has an end  50  that connects to a hose, hose fitting, or the like (not shown) and an opposite end  52  that faces and is configured to be connected to the nipple  14 . A valve  54  is located within the socket body  44  and includes a valve head section  56  that extends through and beyond the face of the end  52  of the cam-engagement housing  46 . A valve guide  58  is supported in a stationary position within the socket body  44 , and the valve  54  is movable relative to the valve guide  58  in a longitudinal direction within the coupler  12 . A valve spring  60  is captured between the valve guide  58  and valve  54  to resiliently urge the valve  54  in a normally-closed position preventing fluid flow through the coupler  12 . In this position, a part of the valve  54  having a valve seal  64  engages an annular tapered lip  62  of the socket body  44  to create a normally-closed fluid-tight seal. 
         [0031]    The socket body  44  carries an elastomerically energized ultra-high molecular weight (UHMW) cup seal  66  extending thereabout. See  FIG. 8 . As will be discussed in greater detail below, this seal  66  creates a fluid tight seal with an inner diameter surface of the nipple body  18  during an early stage of connection of the coupler  12  to the nipple  14  thereby preventing or reducing unwanted release of fluid, such as CO 2 , during connection and disconnection processes. 
         [0032]    The cam-engagement housing  46  and sleeve  48  cooperate to provide the coupler  12  with two different retention ball systems, including a set of latching balls  68  and a separate set of locking balls  72 . As best shown in  FIG. 7 , the set of latching balls  68  is located closer to the end  52  of the coupler  12  than the locking balls  72 , and the locking balls  72  are spaced a pre-determined distance behind the latching balls  72  relative to the end  52  of the coupler  12 . 
         [0033]    Each of the latching balls  68  may be seated within and partially protrude through tapered openings  70  in the cam-engagement housing  46 , but may not completely pass through the tapered openings  70 . For example, as best illustrated in  FIG. 8 , when the sleeve  48  is in a normal position (as shown in  FIG. 8 ), which is hereinafter referred to as the normal forward position of the sleeve  48 , an inner peripheral surface of the sleeve  48  locks the latching balls  68  in an inward position (i.e., radially inward relative to the coupler  12 ). See  FIG. 8 . In this inward position, the nipple  14  may not be inserted into the coupler  12  beyond the latching balls  68  because the outer peripheral surface of the nipple  14  cannot fit through the reduce-sized opening created within the coupler  12  by the latching balls  68  protruding through the openings  70 . 
         [0034]    The sleeve  48  may be positioned in the normal forward position as shown in  FIG. 8  or in a retracted position in which the sleeve  48  is slid rearward in a longitudinal direction away from the end  52  of the coupler that engages the nipple  14 . When the sleeve  48  is caused to be slid to the retracted position via the hand of the operator, the latching balls  68  are no longer trapped in the inward position and are permitted to extend to an outward position (i.e., radially outward relative to the coupler  12 ) such that they no longer protrude through the openings  70  and no longer restrict the nipple  14  from passing through the coupler. For example, see the position of the sleeve  48  as shown in the retracted position in  FIG. 10  and see the latching balls  68  deflected to the outward position by the nipple  14 . 
         [0035]    In addition to preventing or permitting passage of the nipple  14  through the coupler  12 , the latching balls  68  can also be manipulated to engage cam paths  34  of the nipple  14  for purposes of latching the coupler  12  to the nipple  14 . Thus, the number and spacing of latching balls  68  may match the number and spacing of cam paths  34  in a manner permitting the latching balls  68  to register with the cam paths  34 . The number of latching balls or cam paths may be two or more, such as three to twelve or more in larger sized couplings. 
         [0036]    As best shown in  FIG. 11 , when the latching balls  68  register with cam paths or grooves  34 , a sleeve spring  76  retained on the cam-engagement housing  46  resiliently and automatically urges the sleeve  48  into the normal forward position. In this position, the latching balls  68  are once again captured in the inward position protruding through openings  70 . Thus, the latching balls  68  engage the cam paths  34 . In this condition, the coupler  12  is connected to the nipple  14  and cannot be accidentally disconnected from the nipple  14  provided the sleeve  48  remains in the normal forward position. This is because the cam paths  34  terminate in closed proximal ends  38  that do not extend through the end face  42  of the nipple body  18 . 
         [0037]    In addition to the set of latching balls  68 , a set of locking balls  72  also extend through tapered openings  74  in the cam-engagement housing  46 . Similar to the latching balls  68 , each of the locking balls  72  may be seated within and partially protrude through the tapered openings  74  in the cam-engagement housing  46 , but may not completely pass through the tapered openings  74 . 
         [0038]    When the sleeve  48  is in a normal position (as shown in  FIG. 8 ), at least one recess  78  formed in the inner peripheral surface of the sleeve  48  is in alignment with the locking balls  72  so that the locking balls  72  may retract outwardly and not protrude through the tapered openings  74 . However, when the sleeve  48  is placed in the retracted position, the inner peripheral surface of the sleeve  48  captures the locking balls  72  in an inward position (i.e., radially inward relative to the coupler  12 ). In this inward position, the nipple  14  (although able to be inserted beyond the latching balls  68 ) may not be inserted into the coupler  12  beyond the locking balls  72  because the outer peripheral surface of the nipple  14  cannot fit through the reduce-sized opening created within the coupler  12  by the locking balls  72  protruding through the openings  74 . 
         [0039]    Accordingly, when the end face  42  of the nipple  14  is abutted against the locking balls  72 , the latching balls  68  will have been advanced on the nipple  14  a needed distance to engage within the proximal closed ends  38  of the cam paths  34 . If the latching balls  68  are not registered with the cam paths  34 , the coupler  12  may be slightly moved or rotated relative to the nozzle until the latching balls  68  align with and are received within the proximal closed ends  38  of the cam paths  34 . As this occurs, the sleeve  48  will automatically and resiliently return to the normally forward position in which the recess  78  will again be in alignment with the locking balls  72 . 
         [0040]    When the locking balls  72  are aligned with the recess  78 , the locking balls  78  are permitted to move outwardly thereby permitting the nipple  14  to be advanced further into the coupler  12  beyond the location of the locking balls  72 . The further advancement is accomplished by rotation of the coupler  12  relative to the nipple  14  as controlled by the latching balls  68  following the helical path of the cam paths  34 . Shortly after initiation of the rotation, the locking balls  72  are captured within the recess  78  of the sleeve  48  by the confronting outer diameter surface  36  of the nipple  14 . The locking balls  72  ride along and engage a path on an outer diameter of the nipple body  18  between the cam paths  34  and do not enter the cam paths  34 . In this position, the locking balls  72  are able to prevent the sleeve  48  from inadvertently moving to the retracted position. This prevents any accidental disconnection of the coupler  12  from the nipple  14  due to unwanted moving of the sleeve which would otherwise permit the latching balls  68  to be disengaged from the cam paths  34 . 
         [0041]      FIGS. 9-12  show the various stages of engagement of the coupler  12  to the nipple  14  during a connection or disconnection process and show valve operation occurring within the coupling  10  during the different stages. 
         [0042]    In  FIG. 9 , the coupler  12  and nipple  14  are shown in a completely disengaged arrangement. The valves  54  and  22  within the coupler  12  and nipple  14 , respectively, are in the normally-closed condition as discussed above and no release of the cryogenically controlled liquid through either the coupler  12  or nipple  14  is enabled. In addition, the sleeve  48  is shown in a normal forward position on the cam-engagement housing  46  via the force of the sleeve spring  76 . 
         [0043]    When the sleeve  48  is in the normal forward position as shown in  FIG. 9 , the latching balls  68  are captured in an inward most position such that the latching balls  68  protrude through the openings  70  preventing passage of the nipple  14 . In this position, the latching balls  68  cannot extend over the lip of the end face  42  of the nipple  14 . Thus, the coupler  12  cannot be engaged with the nipple  14  in the condition shown in  FIG. 9 . However, the coupler  12  can be slightly applied on the nipple  14  such that the end face  42  of the nipple is flush and square against the inwardly protruding latching balls  68  of the coupler  12 . 
         [0044]      FIG. 10  shows the condition of the coupler  12  relative to the nipple  14  when an operator grips and pulls the sleeve  48  against the force of the sleeve spring  76  in a rearward direction and into the retracted position on the cam-engagement housing  46 . In this retracted position, the set of latching balls  68  are permitted to move outward to permit the cam-engagement housing  46  and set of latching balls  68  to extend over and onto the lip of the nipple body  18 . See  FIG. 10 . 
         [0045]    As shown in  FIG. 10 , in this early stage of the connection process, both valves  54  and  22  remain normally-closed and the head section  56  of the valve  54  is spaced from a complementary receiving surface  80  of the valve  22  of the nipple  14 . Also, in  FIG. 10 , the cross section is shown such that the closed proximal ends  38  of one of the cam paths  34  and an opposite closed distal end  40  of another one of the cam paths  34  are shown. 
         [0046]    The coupler  12  may be advanced onto the nipple  14  from the position shown in  FIG. 10  until the end face  42  of the nipple abuts against the locking balls  72  which are caused to protrude through openings  74  due to the sleeve  48  being positioned in the retracted position as discussed above. In this condition, the latching balls  68  extend a sufficient distance onto the nipple  14  to engage within the closed proximal ends  38  of the cam paths  34 . If this engagement has not yet occurred, slight rotation of the coupler about the nipple  14  will provide proper alignment for the engagement of the latching balls  68  with the cam paths  34 . 
         [0047]    When the latching balls  68  engage the cam paths  34 , the sleeve  48  returns to the normal forward position thereby trapping the latching balls  68  within the cam paths  34  and permitting the locking balls to extend into the recess  70 . At this stage of the connection process, both valves  54  and  22  remain normally-closed; however, the head section  56  of the valve  54  is now abutted against the complementary receiving surface  80  of the valve  22  of the nipple  14 . 
         [0048]    In this condition, the operator now must rotate the coupling  12  about one-quarter to one-eighth of a turn relative to the nipple  14  to advance the coupling  12  further and fully onto the nipple  14  since the latching balls  68  must follow the helical path defined by the cam paths  34 . 
         [0049]      FIG. 11  shows the stage of the process in which the latching balls  68  have traveled approximately half the distance from the closed proximal ends  38  to the closed distal ends  40  of the cam paths  34 . At this stage in the process, the head section  56  of valve  54  engages the complementary receiving surface  80  of the valve  22  and causes the valve  54  in the coupler  12  to be urged into an open flow condition. However, the valve  22  in the nipple remains in the normally closed position. 
         [0050]    In addition, with the sleeve  48  in the normal forward position, the locking balls  72  are aligned with the recess  78  and firmly engaged between the sleeve  48  within the recess  78  and an outer diameter of the nipple body  18  between and outside of the cam paths  34 . The locking balls  72  are offset from the latching balls  68  and are never in a position to engage the cam paths  34 . The importance of this arrangement is that, in this condition, the sleeve  48  cannot be moved relative to the cam-engagement housing  46 . Thus, the sleeve  48  is locked in the forward position. This prevents the latching balls  68  from losing engagement with the cam paths  34  due to inadvertent movement of the sleeve  48 . 
         [0051]    Also, in  FIG. 11 , the O-ring energized UHMW seal  66  of the socket body  44  of the coupler  12  has engaged and forms a fluid-tight seal against the inner diameter of the nipple body  14 . Thus, even though the valve  54  in open, the seal  66  prevents undesired escape of the fluid from the coupling  10 . 
         [0052]      FIG. 12  shows the coupler  12  after it has been fully rotated to a final connection condition. Here, the latching balls  68  have been fully advanced within the cam paths  34  into the circumferentially-extending ends  40  of the cam paths  34  where the cam paths  34  terminate and form a detent. The circumferentially-extending ends  40  (i.e., detents) of the cam paths  34  prevent movement or rotation of the coupler  12  relative to the nipple  14 . In addition, this further advancement of the coupler  12  relative to the nipple  14  causes the fully compressed valve spring  60  and valve  54  of the coupler  12  to provide a force against the valve  22  of the nipple  14  to position the valve  22  in an open position permitting flow through the nipple  14  and through the coupling  10 . 
         [0053]    Accordingly, in the position shown in  FIG. 12 , the cryogenically controlled liquid may flow through the coupling  10  for delivery to the receiving facility and a fluid-tight seal between the coupler  12  and nipple  14  has been created to prevent any leakage or escape of the low temperature liquid under high pressure. Further, the latching balls  68  are captured by the sleeve  48  within the cam paths  34  and the locking balls  72  prevent inadvertent movement of the sleeve  48 . Accordingly, any accidental disconnection of the coupler  12  from the nipple  14  is prevented. 
         [0054]    The above referenced steps are performed in reverse relative to disconnecting the coupler  12  from the nipple  14 . An operator would first rotate the coupler  12  relative to the nipple  14  for about a one-eighth to one-quarter turn. This moves the latching balls  68  to the closed proximal ends  38  of the cam paths  34 . As this occurs, first the valve  22  of the nipple  14  is permitted to return to a normally-closed position, such as shown in  FIG. 11 , and then the valve  54  of the coupler  12  is returned to a normally-closed position. This minimizes any possible exposure of CO 2  or the like to the operator and prevents any damage that may be caused by the liquid being under high pressure. In this condition, the locking balls  72  extend beyond the lip of the nipple body  18  thereby allowing the operator to pull the sleeve into the retracted position to enable disengagement of the latching balls  68  relative to the cam paths  34 . The coupler  12  can then be removed from the nipple  14 . 
         [0055]    The foregoing description and specific embodiments are merely illustrative of the principles thereof, and various modifications and additions may be made to the apparatus by those skilled in the art, without departing from the spirit and scope of this invention.