Abstract:
A coupler for use in sealing a joint between two pipes. The coupler is comprised primarily of two center sections and two end caps. The two center sections are engagable with one another and the two end caps are engagable with the center sections. Gasket rings create seals between the two center sections as well as between the two center sections and the cap rings. The center sections are dimensioned to create a volume of space within the coupler, thus permitting the coupler to accommodate offset joints. The gasket rings between the cap rings and the center sections can be longitudinally spaced apart, minimizing the angular deflection of the coupler with respect to the pipes when the pipe joint is offset. The center sections and end caps can be lockably engaged.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     REFERENCE TO A SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX 
     Not Applicable. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is illustrated in the accompanying drawings, in which: 
         FIG. 1  is an exploded, perspective of a disassembled coupler according to one embodiment of the present invention; 
         FIG. 2  is an exploded cross-sectional view of a disassembled coupler according to one embodiment of the present invention; 
         FIG. 3  is a perspective view of an assembled coupler according to one embodiment of the present invention; 
         FIG. 4  is a cross-sectional view of an assembled coupler according to one embodiment of the present invention; 
         FIG. 5  is a cross-sectional detail of an assembled coupler according to one embodiment of the present invention; 
         FIG. 6  is an illustrative diagram showing a parallel, lateral offset pipe joint and the reduced angular misalignment between the pipes and the coupler achieved when the seals engaging the offset pipes are spaced from the offset joint, as in the present invention; 
         FIG. 7  is a cross-sectional view of a coupler according to one embodiment of the present invention installed on an angularly offset pipe joint; 
         FIG. 8  is a cross-sectional view of a coupler according to one embodiment of the present invention installed on a longitudinally offset pipe joint; 
         FIG. 9  is a detail view of a locking mechanism according to one embodiment of the present invention; 
         FIG. 10  is a detail view of a locking mechanism according to another embodiment of the present invention; and 
         FIG. 11  is a detail view of a locking mechanism according to another embodiment of the present invention. 
         FIGS. 12A and 12B  show perspective and cross-sectional views, respectively, of a gasket having a round cross-section. 
         FIGS. 13A and 13B  show perspective and cross-sectional views, respectively, of a gasket having an X-shaped cross-section. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     As illustrated in  FIG. 1 , the coupler  10  of the present invention can be used as a redundant coupler or primary coupler; the term “redundant” here meaning that the coupler  10  of the present invention can be installed over an existing primary coupler (see  FIG. 4 ). It is suitable for use with all types of fluids and in positive or negative pressure environments. 
     The coupler  10  of the present invention is generally comprised of four rigid components  12 ,  14 ,  16 , and  18  and three gasket rings  20 ,  22 , and  24 . The rigid components include a first center section  12 , a second center section  14 , a first cap ring  16  and a second cap ring  18 . (Note that when components or sides of components are described herein as “first” and “second,” etc., the “first” will typically be to the left of the “second.” The two exceptions to this convention being the three gasket rings and three abutments, as explained below. For the gasket rings and abutments, the component in the middle position is referred to as the “first.”) These rigid components are typically cylindrical. As used herein, the term “cylindrical” is used to refer to the general shape of the component and does not mean that the component (1) does not vary in size from one end to the other (e.g. is not stepped or belled), and (2) does not have other surface features, including but not limited to threads, abutments, tabs, and flanges. 
     Turning now to  FIG. 2 , the rigid components  12 ,  14 ,  16 , and  18  each have first and second end. First center section  12  has a first end  26  and a second end  28 . Second center section  14  has a first end  30  and a second end  32 . First cap ring  16  has a first end  40  and a second end  42 . Second cap ring  18  has a first end  44  and a second end  46 . Abutting ends of these components are designed to engage one another. Accordingly, the second end  28  of the first center section  12  is dimensioned to engage the first end  30  of second center section  14 . Likewise, the second end  42  of first cap ring  16  is dimensioned to engage the first end  26  of first center section  12  and the first end  44  of second cap ring  18  is dimensioned to engage the second end  32  of the second center section  14 . 
     Furthermore, a gasket ring is positioned between the center sections  12  and  14  and also between each cap ring  16  and  18  and the center the cap ring engages. Specifically, first gasket ring  20  resides between first center section  12  and second center section  14 , second gasket ring  22  resides between first cap ring  16  and first center section  12 , and third gasket ring  24  resides between second center section  14  and second cap ring  18 . When the rigid components  12 ,  14 ,  16 , and  18  are engaged, the gasket rings  20 ,  22 , and  24  allow for a seal to be created between the components. The second and third gasket rings  22  and  24 , in addition to creating a seal between the cap rings  16  and  18  and the center section  12  and  14 , also create a seal around the pipes  2  and  4  ( FIG. 3 ). 
     The particular embodiment of the present invention  10  shown in  FIG. 2  has threads to allow the rigid components to engage one another. Specifically, the outer surfaces  48  and  52  of first and second ends  26  and  28  of first center section  12  are threaded. Likewise, the inside surface  56  of the first end  30  and the outside surface  58  of the second end  32  of the second center section  14  are threaded. Finally, the inside surfaces  64  and  66  of cap rings  16  and  18 , respectively, are threaded. Of course, the present invention is not limited to using threads to make the rigid components engagable. Any means known in the art could be used to combine the components and this disclosure and the claims appended hereto should be read to include all means known in the art. 
     In further reference to  FIG. 2 , this particular embodiment of the present invention has flanges  36 ,  50 ,  60 ,  62 , and  68  and groove  38  to engage gasket rings  20 ,  22 , and  24 . Specifically, first gasket ring  20  is received between flange  36  in first center section  12  and groove  38  in second center section  14 . Likewise, second gasket ring  22  is received between flange  62  and flange  50  and third gasket ring  24  is received between flange  60  and flange  68 . Herein, references to, for example, “the flanged inner surface  62  of first cap ring  16 ” and “the flange  62  on the inner surface of first cap ring  16 ” mean the same thing—the term “flanged” simply meaning that there is a flange thereon. 
     Continuing to refer to  FIG. 2 , in this particular embodiment of the present invention, the second end  28  of first center section  12  and the first end  30  of second center section  14  are larger in diameter than the first end  26  of first center section  12  and second end  32  of second center section  14 . This feature creates a volume of space  34  ( FIGS. 4 and 5 ) inside the coupler  10  sufficient to allow the coupler  10  of the present invention to be used over a separate primary coupler  6  ( FIG. 4 ). Furthermore, as more fully explained below, this volume of space contributes to this coupler&#39;s ability to maintain its seal around the joint even when the joint is offset. Because this coupler does not bear directly on the joint itself (i.e. at or near the very ends of the pipes  2  and  4 ), if the joint is offset, it has little effect on the coupler. The volume of space  34  inside the coupler  10  allows the coupler  10  to accommodate an offset joint without losing its seal around the joint. Moreover, the manner in which the joint is offset (longitudinally, laterally, angularly, or any combination of the above) is immaterial. 
       FIG. 3  shows a perspective view of a coupler  10  according to one embodiment of the present invention installed upon the joint between pipes  2  and  4 . Referring now to  FIGS. 4 and 5 , this particular embodiment of coupler  10  has abutments  70 ,  72 , and  74 , which prevent the over tightening of the components and resulting deformation of the gasket rings. Specifically, abutment  70  prevents second center section  14  from being over tightened onto first center section  12 , thereby preventing gasket ring  20  from being deformed. Likewise, abutment  72  prevents first cap ring  16  from being over tightened onto first center section  12 , thereby preventing gasket ring  22  from being deformed. Finally, abutment  74  prevents second cap ring  18  from being over tightened onto second center section  14 , thereby preventing third gasket ring  24  from being deformed. 
     With respect to gasket rings  20 ,  22 , and  24 , although the gasket rings in the figures have a square cross-section, the present invention can utilize gasket rings of a variety of configurations. For example, one or more of the gasket rings can have a rectangular cross section, a circular or oval cross section ( FIGS. 12A and 12B ), an X-shaped cross section ( FIGS. 13A and 13B ), or a C-shaped cross section. Gasket rings having any configuration known in the art can be utilized with the coupler  10  of the present invention. Furthermore, the gasket rings can be made of any single material known in the art as well as any composite material known in the art. In further reference to  FIG. 4 , note that in this particular embodiment of the present invention second and third gasket rings  22  and  24  are spaced apart from the joint between pipes  2  and  4 . This feature permits the coupler of the present invention to maintain its seal around the pipe joint even when the pipes are offset. 
     Referring now to  FIG. 6 , an illustrative figure that does not show the coupler of the prior art but is intended to show the advantage of spacing longitudinally the second and third gasket rings  22  and  24  (i.e. apart from one another and from the ends of pipes  2  and  4 ). Note first that the pipe joint in  FIG. 6  is laterally offset. That is, the centerlines of pipes  2  and  4 , while parallel, are not coincident. When this occurs, any coupler that is used to seal the joint will span from the first pipe to the second pipe and will be at an oblique angle (slightly out of parallel) with respect to both pipes.  FIG. 6  shows that, as the two points at which the coupler contacts the pipes are moved farther apart and away from the joint, the degree to which the coupler is out of parallel with the pipes decreases. The closer the coupler is to being parallel with the pipes, the more likely it is to maintain its seal around the joint. Accordingly, it is advantageous to have the coupler contact the pipes longitudinally spaced away from the joint. 
     For example, when the two points at which the coupler contacts the two pipes are A-A and A-A in  FIG. 6 , the degree of angular misalignment is shown as angle A. When the two points are moved farther apart, however, to points B-B and B-B, the degree of angular misalignment decreases. This means that the coupler of the present invention is more likely to maintain its seal around the joint between offset pipes than a coupler that contacts the pipes closer to the joint. This feature contributes to the ability of the coupler  10  of the present invention to maintain its seal around joints, even when they are offset laterally ( FIG. 6 ), angularly ( FIG. 7 ), or longitudinally ( FIG. 8 ), or any combination of these modes. 
     Turning now to  FIG. 9 , another feature of the present invention is that the rigid components  12 ,  14 ,  16 , and  18  can be locked together. Locking the components prevents the coupler  10  from losing its seal around the pipe joint, even when the coupler  10  is subjected to vibration and/or substantial temperature swings. The specific embodiment of the present invention  10  shown in  FIG. 9  has a locking mechanism comprised of a first tab  76  on first center section  12  and a second tab  78  on second center section  14 . Tabs  76  and  78  have posts  84  and  86 , respectively, extending therefrom. When the tabs  76  and  78  are brought together, a C-shaped clip  80  with holes  88  can be clipped onto the posts  84  and  86  and around tabs  76  and  78 .  FIG. 10  shows a similar locking mechanism that utilizes a latch  90  instead of a C-shaped clip. Latch  90  can be spring-loaded.  FIG. 11  shows a third embodiment of the locking mechanism wherein tabs  76  and  78  and buckle  92  are used to ensure that first center section  12  and second center section  14  remain fully engaged. The means for locking of the present invention encompass all of these structural variations as well as any other latch or buckle known in the art that could be used to lock the two center sections  12  and  14  to one another or to cap rings  16  and  18 . 
     Having hereby described the subject matter of the present invention, it should be apparent that many substitutions, modifications, and variations of the invention are possible in light of the above teachings. It is therefore to be understood that the invention as taught and described herein is only to be limited to the extent of the breadth and scope of the appended claims.