Abstract:
A coupling for coupling a pair of axially aligned adjacent pipes. The coupling including a substantially cylindrical sleeve having an inner surface including a recess therein where the cylindrical sleeve has a first end area and a second end area. The second end area includes a tab extending therefrom that is selectively alignable and insertable within the recess. A liner may be positioned along the inner surface of the sleeve.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Technical Field  
           [0002]    The invention relates generally to a coupler or coupling for connecting axially aligned passages and, more particularly, to a pipe coupling for fluidly sealingly connecting two adjacent axially aligned pipes. Specifically, the invention relates to a pipe coupling for use in generally low pressure or low vacuum applications for coupling a pair of axially aligned adjacent pipes, where the pipe coupling includes a substantially cylindrical sleeve having an inner surface including a recess therein where the cylindrical sleeve has a first end area and a second end area, where the second end area includes a tab extending therefrom that is selectively alignable and insertable within the recess.  
           [0003]    2. Background Information  
           [0004]    As is well known, pipes or other enclosed passages are used to transport all types of gaseous, liquid and even solid media. The types of gaseous, liquid, solid, slurry, or other mixtures that may be transported using pipes and other passages is almost unlimited, and may include sawdust being removed from a wood shop, flour being transported to another processing step during manufacture at a flour mill, chicks being moved within a brooder, slurries being transported for disposal or reclamation, and so on. In many applications, the system is under low pressure or vacuum, or none at all, and may or may not required a sealed or enclosed passage.  
           [0005]    In all of the above and many other applications, the pipes or other passages are manufactured and sold in sections or lengths out of convenience in manufacturing, shipping, storage, lifting and ultimately use in many limited space locations. Often multiple pipes or passages are needed in series to get from a first point to a second point, that is to move the material to be transported via an enclosed passage from the first point to the second point. Where multiple pipes or passages are needed, a coupler or coupling is typically one method of connecting the ends of the multiple pipes or passages together, particularly when the one end of each pipe is adjacent and axially aligned.  
           [0006]    One version of a prior art coupling is shown in FIGS.  1 - 3 . This prior art coupling includes a metal sleeve or outer layer with a rubber liner therein. The metal sleeve must overlap itself thus causing an off-round cross section to the coupling as best shown by the enlarged inset shown in FIG. 3. This creates a stress point for both the metal sleeve and the rubber liner.  
           [0007]    Often a static strip is also required for grounding whereby the static strips function to electrically connect the coupling to the adjacent pipes which are seated within the coupling against the rubber liner. This static strip provides a potential leak path.  
           [0008]    These and the other couplings patented, developed and marketed have to varying degrees satisfied some of the needs and desires of users. However, each tends to have some problems and difficulties.  
           [0009]    The need thus exists for an improved coupling that addresses the problems of the prior art devices and also provides for improvements.  
         BRIEF SUMMARY OF THE INVENTION  
         [0010]    In view of the foregoing, advantages are obtained by the improved coupling of the present invention, the general nature of which may be stated as including a coupling for coupling a pair of axially aligned adjacent pipes where the coupling includes a substantially cylindrical sleeve having an inner surface including a recess therein where the cylindrical sleeve has a first end area and a second end area, whereby the second end area includes a tab extending therefrom that is selectively alignable and insertable within the recess. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    The preferred embodiment of the invention, illustrative of the best mode in which applicant has contemplated applying the principles of invention, is set forth in the following description and is shown in the drawings and is particularly and distinctly pointed out and set forth in the appended claims.  
         [0012]    [0012]FIG. 1 is a perspective view of one form of prior art;  
         [0013]    [0013]FIG. 2 is an end view of the prior art coupling shown in FIG. 1;  
         [0014]    [0014]FIG. 3 is an enlarged sectional view of the wall of the prior art coupling of FIGS.  1 - 2  showing the outer layer overlap;  
         [0015]    [0015]FIG. 4 is a general schematic of a piping system for moving materials from a first point to a second point where the piping system requires multiple pipes coupled together using the coupling of the present invention;  
         [0016]    [0016]FIG. 5 is a perspective view of the coupling of the present invention;  
         [0017]    [0017]FIG. 6 is an exploded view of the coupling of the present invention as shown in FIG. 5;  
         [0018]    [0018]FIG. 7 is a top view of the coupling of the present invention of FIGS. 56;  
         [0019]    [0019]FIG. 8 is a side view of the coupling of the present invention of FIGS.  5 - 7 ;  
         [0020]    [0020]FIG. 9 is an end view of the coupling of the present invention of FIGS.  5 - 8 ;  
         [0021]    [0021]FIG. 10 is an enlarged end view of a portion of the coupling of the present invention of FIGS.  5 - 9 ;  
         [0022]    [0022]FIG. 11 is a sectional view taken along lines  11 - 11  in FIG. 9 with pipes also sectionally shown and added therein; and  
         [0023]    [0023]FIG. 12 is a process view of the metal sleeve portion of the coupling of the present invention prior to forming it into a substantially cylindrical sleeve. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0024]    Referring to the drawings, wherein like numerals represent like parts throughout the several views, there is generally disclosed in FIG. 4 a system  20  where it is desirable to move materials in a low pressure or low vacuum environment from a first point  22  to a second point  24  via an enclosed passage  26 . The enclosed passage  26  may require more than one length of pipe, in this case pipe length  28 A and  28 B which must be coupled together using the coupling  30  of the present invention.  
         [0025]    As best shown in FIGS.  5 - 9 , coupling  30  includes a metal sleeve  32 , a plurality of fasteners  34 , and a liner  36 . Coupling  30  may also optionally include an insert spring  38 .  
         [0026]    In more detail, sleeve  32  is initially cut or otherwise made in the shape shown in FIG. 12 whereby it is a flat metal sheet with a front surface  40  (which eventually forms the inside surface of the metal sleeve of the coupling), a back surface  42  (which eventually forms the outside surface of the metal sleeve of the coupling), and a thin peripheral edge  44  therebetween. The front and back surface are basically defined by a first end area  46  and a second end area  48  with a mid-section  50  therebetween. Adjacent the first end area  46  within the mid-section is a notched area  52  that is recessed or indented when viewed from the front surface  40  while raised or protruding when viewed from the back surface  42  so as to not be planar with either surface. The second end area  48  is divided into a first section  54  and a second section  56  where the first section  54  is trimmed or otherwise created such that it defines a tab  58  that is of a lesser width than the second section  56  which is of the same width as the mid-section  50  and the first end area  46 .  
         [0027]    The flat metal sheet of FIG. 12 is formed into the metal sleeve  32  that is shown in FIGS.  5 - 9 . Specifically, the first end area  46  is folded around itself several times and crimped so as to form a first reinforced end  60  which includes a plurality of fastener passages  62 . The folding and crimping are stopped once the notched area  52  is positioned just into the bend  64  so as to provide in effect a slot in which the tab  58  will fit as explained below and shown in FIG. 9. The mid-section  50  is formed into a substantially cylindrical body as shown in FIGS.  5 - 9  whereby the cylindrical body includes the notched area  52  which extends out from therefrom as shown in FIGS.  5 - 6 . The second section  56  of the second end area  48  is folded around itself several times and crimped similar to the first end area so as to form a second reinforced end  66  which includes a plurality of fastener passages  68 ; however, the first section  54  of the second end area  48  is not folded or crimped and rather extends outward as the tab it is and is alignable and insertable within the notched area  52  via the slot.  
         [0028]    Fasteners  34  may be any form of fastener capable of pulling the first reinforced end  60  and the second reinforced end  66  closer together thereby reducing the diameter of the metal sleeve  32  across its mid-section  50 . In one embodiment, the fasteners  34  include bolts  70 , washers  72  and nuts  74 .  
         [0029]    Liner  36  may be any form of a sealable material such as rubber and of any design capable of sealing the outer surface of any pipe length such as  28 A to the inner surface  40  of the metal sleeve. In the embodiment shown, the liner is a rubber liner and it includes a serrated, toothed, stepped, wavy, linear, or other cut  80  therein.  
         [0030]    The optional insert spring  38  is typically some form of a spring designed to spring outward from a central axis so as to push the liner  36  against the inner surface  40  of the sleeve  32 . In the embodiment shown, the spring  38  is a cylinder that is squeezable for insertion within the sleeve whereby it springs back once released.  
         [0031]    The sleeve  32  may also include one or more spikes  90  extending inward from the sleeve proximate each end thereof. These spikes are designed to engage with the pipe to both assist in holding the pipe within the coupling as well as provide for static electricity flow.  
         [0032]    In use, a pipe length such as  28 A is placed in one end of the coupling  30 , and a second pipe length such as  28 B is placed in the other end of the coupling  30 . In both instances the end of the pipe length to be sealed is surrounded by the liner  36  which is surrounded by the sleeve  32 . Spring  38  may be within the coupling to hold the liner in place. The fasteners  34  are engaged such that the first reinforced end  60  and the second reinforced end  66  are pulled closer together thereby securing the pipe lengths within the coupling. The liner seals the system so as to provide for a low pressure seal between the pipe lengths.  
         [0033]    The tab  58  seats within the notched area  52  such that the sleeve  32  maintains a round cross section thereby eliminating stress points. This is best shown in FIGS. 9 and 10 as FIG. 10 is cross section taken through the notched area  52 .  
         [0034]    In a different embodiment the tab  58  is not part of the sleeve body  32 , and instead is a separate body that is fastened to the second reinforced end  66  and provides the same tab-like body to finish out the cylindrical shape of the sleeve and seat within the notched area  52 .  
         [0035]    In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed.  
         [0036]    Moreover, the description and illustration of the invention is an example and the invention is not limited to the exact details shown or described. Other modifications of the invention will be apparent to those skilled in the art in light of the foregoing description.  
         [0037]    Having now described the features, discoveries, and principles of the invention, the manner in which it is constructed and used, the characteristics of the construction, and the advantageous new and useful results obtained; the new and useful structures, devices, elements, arrangements, parts, and combinations are set forth in the appended claims.