Abstract:
A grip and fitting assembly for coupling an air hose to a gladhand coupler. The grip being flexible and tapered with a tubular interior through which may pass a length of hose shielded and protected by the grip. The grip is affixed to a fitting attachable to the gladhand coupler on a first threaded end thereof and attachable to the air hose on a second barbed end thereof. The grip is configured with one or more internal keyway boss which aligns and interlocks with one or more corresponding keyway recess on a retaining shoulder formed between the ends of the fitting. The secure, snap-fit attachment between the grip and fitting ensures ease of operation, installation, maintenance, along with increased durability, weather-resistance, efficiency, usability, and reliability of the coupling.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims benefit of priority of U.S. Provisional Patent Application Serial No. 62/287,420 filed Jan. 26, 2016, which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention described herein relates generally to the field of grip fitting assemblies for tube and hose connections. More specifically, the present invention provides improved operation, installation, durability, weather-resistance, and reliability of flexible grips, grip fittings and grip fitting assemblies for tube and hose line connections. 
       BACKGROUND OF THE INVENTION 
       [0003]    Applications of grips, fittings and grip fitting assemblies for tube and hose line connections within industrial and commercial environments require resistance to harsh environments and reliability under stress and strain forces during installation and operation. Such tube and hose lines may involve high pressure hydraulics or air and often require some flexibility of the tube or hose. 
         [0004]    For example, air hose connections are commonly found in applications within the freight hauling industry. Such connections use a device known as a gladhand or gladhand coupler. This is an interlocking hose coupling fitted to hoses supplying pressurized air for air brake operation between a tractor cab unit and a freight trailer, or from a locomotive to railway air brakes on railroad cars. Gladhand couplers resemble a pair of “hands shaking” when interlocked and from where their name is derived. Gladhands are designed to allow the driver to manually disconnect hoses between tractor/trailer or between railcars without a mechanic or tools. They sometimes are quick release to speed up brake release time. Often, gladhands are color coded with service lines being blue and emergency brake lines being red. Mated rubber grommets provide a positive seal, and the joined halves may separate during operation if certain pull stresses are present at the hose or tube connection. Gladhand couplers are typically standardized in size and mating geometry which allows them to be connected to each other, for example allowing either end of a railcar to be connected to the end of a train or for one trucking company&#39;s tractor cabs to connect to any number of freight trailers. 
         [0005]    Inherent to the freight industry is the constant coupling and decoupling of gladhand connections as trailers are left for loading or unloading and other trailers are picked up for delivery. Gladhands are of course affixed to a length of air hose or tube. The manual act of coupling and decoupling gladhands places stress and strain upon the connected hose. This is exacerbated by the fact that gladhands are prone to corrosion making their mating surfaces more difficult to couple and uncouple over time. During installation and operation of an air brake hose in the freight hauling context, the flexible hose undergoes stress from bending, twisting, and kinking, particularly at the fitting ends of the air brake lines. For instance, tractor-trailer operators subject air brake lines to twisting while bending them into position in tight quarters between tractor and trailer. Drivers and fleet maintenance personnel repetitively connect and disconnect air brake lines between the tractor and trailer using hand holds on the hose at the fittings to achieve the needed leverage to secure and release gladhand connections. 
         [0006]    Conventional grips, fittings and grip fitting assemblies, however, do not offer sufficient protection against kinking of the hose and tube at the gladhand connections. Conventional hose and tube assemblies using only coiled springs at the fittings are subject to corrosion, and provide inadequate protection from the shearing action that takes place during gladhand connection where the spring coils shift and do not prevent kinking and bending during installation and operation. Some rigid grip aids to the gladhand connection process create a more severe angle during tight radius turns putting further stress on air brake lines at the gladhands, reducing the life of air brake hoses and risking failure under operation of the tractor-trailer air brake system. When not in use (e.g., tractor cab not connected to a tractor trailer), air hoses are often stored in a manner such that the weight of the dangling gladhand stresses the hose to which the gladhand is connected. Further, gladhand connections to the hose, which often include grips, fittings and grip fitting assemblies, undergo continuous exposure to the elements while in use, often in frigid conditions. Winter road salts and brine, dirt, grease, and other solvents erode fittings and assemblies of critical air brake connections. For tractor-trailer connections, protection of fittings that join the air hose and gladhand from the elements with weather resistant, low-temperature materials and coatings is essential to the safety of the driver and public highway motorists. 
         [0007]    What is needed is a coupling mechanism that overcomes these and other disadvantages of conventional fittings and fitting assemblies. 
       BRIEF SUMMARY OF THE INVENTION 
       [0008]    One skilled in the art will appreciate that the present teachings can be practiced with embodiments other than those summarized or disclosed below by the Figures and Detailed Description of the Invention to follow. 
         [0009]    In general, the present invention includes a tapered flexible grip and interlocking fitting which combined form a grip fitting assembly. The assembly is used to connect a coupling mechanism such as, but not limited to, a gladhand to a length of hose or tubing. It should be understood that hose and tubing, while sometimes used synonymously, have one major difference. Hoses are generally reinforced in some way. Typical reinforcements are imbedded braid reinforcement, wire reinforcement, reinforcement with a stiffer plastic or other material, dual walls or a very heavy wall. Hose is typically used and rated for applications that involve high pressure. Tubing is not reinforced or is sparsely reinforced and is often used for gravity flow or lower pressure applications. 
         [0010]    For purposes of the following discussion, the term “hose” will be used though should not be considered as limiting the invention. Likewise, the exemplary embodiment of the inventive assembly being used within a gladhand coupling tractor and trailer air hoses should be understood as but one example of an implementation of the present invention. Indeed, the present invention may be implemented within a variety of tube and hose line connections for many industrial and commercial applications. 
         [0011]    The present invention includes a grip and fitting assembly including: a flexible tapered grip having a substantially tubular interior, a first end of which includes an interior seating surface, an annular lip perpendicular to the interior seating surface, and at least one keyway boss located within a sidewall of the substantially tubular interior along the annular lip and adjacent to the interior seating surface; a fitting having a first coupling end, a second coupling end, a retaining shoulder located between the first coupling end and the second coupling end, and an exterior seating surface located between the retaining shoulder and the first coupling end, the retaining shoulder including at least one keyway recess suitably dimensioned to matingly correspond to the at least one keyway boss; wherein the at least one keyway boss and the at least one keyway recess are configured to interlock upon abutment of the interior seating surface with the exterior seating surface so as to preclude rotational movement between the grip and the fitting. 
         [0012]    The present invention also includes a grip and fitting assembly for coupling an air hose to a gladhand coupler, the assembly including: a flexible tapered grip having a substantially tubular interior, a first end of which includes an interior seating surface, an annular lip perpendicular to the interior seating surface, and three keyway bosses located within a sidewall of the substantially tubular interior, the keyway bosses spaced equidistantly along the annular lip and adjacent to the interior seating surface; a fitting having a first coupling end threaded to accept a gladhand coupler, a second coupling end barbed to accept and retain a length of air hose thereon, a retaining shoulder located between the first coupling end and the second coupling end, and an exterior seating surface located between the retaining shoulder and the first coupling end, the retaining shoulder including three keyway recesses each suitably dimensioned to matingly correspond to a related one of the keyway bosses; wherein the keyway bosses and the keyway recesses are configured to interlock upon abutment of the interior seating surface with the exterior seating surface so as to preclude rotational movement between the grip and the fitting. 
         [0013]    The above and other benefits and advantages of the present invention will be readily apparent from the Brief Description of the Drawings and the Invention and Detailed Description to follow. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    Embodiments of the present invention will now be described, by way of example only, with reference to the attached Figures, wherein: 
           [0015]      FIG. 1  shows a perspective view of flexible tapered grip assembly according to the present invention shown with grip and fitting sections disconnected. 
           [0016]      FIG. 2  shows a side view of a complete flexible tapered grip assembly of the invention connected with related elements shown in silhouette. 
           [0017]      FIG. 3  shows an end view of the grip section of the invention, the end view being from the right end of  FIG. 4 . 
           [0018]      FIG. 4  shows a side section view of the grip section of the invention taken along line  4 - 4  of  FIG. 3 . 
           [0019]      FIGS. 5A through 5C  show a series of close-up side views with the fitting section shown intact and a partial length of the grip section shown in a cutaway lengthwise cross section so as to illustrate the before, during, and after stages of fitting insertion into the grip. 
           [0020]      FIG. 6  shows a side view of the complete flexible tapered grip assembly of the invention connected with related elements shown in silhouette taken along line  6 - 6  of  FIG. 3 . 
           [0021]      FIG. 7  shows a close-up view of the flexible tapered grip assembly according to the present invention shown with grip and fitting sections disconnected and the grip section partially cutaway to reveal internal keyway boss structures. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    The present invention will now be described more fully herein with reference to exemplary embodiments, examples of which are illustrated in the accompanying drawings. Embodiments and implementations set forth in the following detailed description do not represent all embodiments and implementations of the claimed invention. 
         [0023]    More specifically, the present invention provides improved operation, installation, durability, weather-resistance, and reliability of flexible grips, grip fittings and grip fitting assemblies for nylon tube and rubber hose line connections in trucking tractor-trailer air brake systems. It should, however, be readily apparent that although such specific implementation within trucking tractor-trailer air brake systems is discussed in accordance with a preferred embodiment, there may be other equally suitable implementations of the present invention outside such context of trucking and which are well within the intended scope of the present disclosure. In particular, the present invention may be applicable to any suitable mobile or fixed implementation including, but not limited to, hydraulic connections, fuel or other fluid transfer, land or marine connections, airplane terminal vestibules, ship-to-shore connections, and may be dry or wet lines. 
         [0024]    With regard to  FIG. 1 , there is seen a three-dimensional illustration showing a flexible tapered grip assembly in accordance with the present invention shown with two sections, one being a fitting  10  and the other being a grip  20 . For purposes of illustration, the assembly is shown where the fitting  10  and grip  20  are in a disconnected position relative to one another. 
         [0025]    The grip  20  is a both flexible and tapered. Flexibility of the grip provides the ability of the grip to bend and yet return to its original shape. The grip  20  itself is a unitary structure fabricated from material suitable for the intended trucking environment which may be hostile to materials—i.e., where wide temperature variations occur and exposure to road salt and a variety of chemicals may occur. One suitable material includes thermoplastic vulcanizates (TPV) which are part of the thermoplastic elastomer (TPE) family of polymers. TPVs offer a combination of elastomeric properties, like compression and tension set, coupled with aging performance and chemical resistance. Other materials such as, but not limited to, ethylene propylene diene monomer (EPDM) thermoset rubber, nylon, or polyvinyl chloride (PVC) may be possible depending upon the intended environment. For example, PVC may not be suitably used for an intended cold weather implementation where flexibility is severely limited at reduced environmental temperatures. The grip  20  may be formed in any suitable manner including, but not limited to, injection molding. It should also be understood that the grip may be colored during molding and provided in a variety of color schemes (i.e., color coded) in accordance with any desired implementation (e.g. red for emergency brake lines, blue for service lines) and which assists to minimize incorrect tractor/trailer connections 
         [0026]    With continued reference to  FIG. 1  and additional reference to  FIG. 2 , the grip  20  is seen as tapered from end to end. In particular, the grip  20  has an increased thickness at a first end  23  tapering to an opposite, second end that includes a tear-resistant rail  22 . The rail  22  is thickened so as to form a suitably reinforced ring around a length of air hose (shown by dotted line  30 ). Oftentimes, such portion of air hose also includes a spring guard (not shown) to assist and support the flexing of the hose. Providing the thickened rail  22  at the spring guard end of the grip  20  prevents tearing of the grip  20  and improves kink resistance of hose and tube made of weather resistant, low-temperature materials and coatings. 
         [0027]    The grip  20  includes traction ridges  21  for an additional non-slip feature when the grip  20  is handled by a user. Recessed areas  26  (and  27  visible in  FIGS. 3 and 4 ) may be provided for corporate labeling or cosmetic logos. 
         [0028]    A fitting  10  is also shown in accordance with the inventive assembly. The fitting  10  includes a first coupling end  15  and a second coupling end  12  between which is located an exterior seating surface  11 . It is the exterior seating surface  11  of the fitting  10  and the interior seating surface  24  of the grip  20  which are intended to abut upon insertion of the fitting  10  into the first end  23  of the grip  20 . Such insertion is shown and described further below with regard to  FIGS. 5A through 5C . 
         [0029]    With continued reference to  FIGS. 1 and 2 , the fitting  10  is seen to include a retaining shoulder  17  located between the first coupling end  12  and the second coupling end  15 . The retaining shoulder  17  has two sides with two very distinct purposes. One side of the retaining shoulder  17  includes a ramped surface  16 . The ramped surface  16  is intended as the part of the fitting  10  which first contacts the first end  23  of the grip  20  upon insertion of the fitting  10  into the grip  20 . The interior seating surface  11  may also include a beveled edge which facilitates the ramped surface  16  to at least initially contact the interior seating surface  11 . The other side of the retaining shoulder  17  includes a shoulder surface  13 . The shoulder surface  13  is opposite the ramped surface  16  and is oriented perpendicular to the exterior seating surface  11 . 
         [0030]    The fitting  10  itself is formed from a corrosion-resistant material such as, but not limited to brass. The first end  15  of the fitting is provided with threading and a hex-nut section  14  of the fitting  10  is provided to enable a user to utilize a wrench to connect the fitting  10  to a coupling mechanism (shown in dotted line as  40 ). The coupling mechanism  40  may be any suitable universal coupling mechanism such as, but not limited to, the aforementioned gladhand or similar coupler. As should be readily apparent from the description thus far and the accompanying  FIG. 2 , the inventive grip and fitting assembly provides a new and useful means of connecting a universal coupling  40  to a length of hose  30 . 
         [0031]    With reference to  FIGS. 3 and 4 , there are respectively shown an end view and a side cross section view of the grip  20 . In particular,  FIG. 3  shows an end view of the grip section of the invention, the end view being from the right end of  FIG. 4  while  FIG. 4  shows a side section view of the grip section of the invention taken along line  4 - 4  of  FIG. 3 . Here, the grip  20  is seen to include three keyway bosses  28   a,    28   b,    28   c  with only two  28   a,    28   b  visible in cross section  FIG. 4 . 
         [0032]    It should be understood that each keyway boss  28   a,    28   b,    28   c  corresponds to a keyway recess  19  located on the fitting  10 . As seen in  FIG. 1 , the retaining shoulder  17  includes such keyway recesses and which are suitably dimensioned to matingly correspond a related keyway boss though only one of three such keyway recesses are visible. From  FIG. 4 , it can be seen that each keyway boss ( 28   a  and  28   b  visible) are located within a sidewall  25  of the substantially tubular interior  25  of the grip  20 . More specifically, each keyway boss is arranged along an annular lip  29  and adjacent to the interior seating surface  24 . It should be noted that while three keyway bosses and three corresponding keyway recesses are discussed, there may be any number of suitable pairs of keyway bosses and recesses such as, but not limited to, one, two, or four. 
         [0033]    The annular lip  29  is configured perpendicular to the interior seating surface  24  and provides a surface against which the shoulder surface  13  of the fitting&#39;s shoulder  17  firmly abuts once the fitting  10  is completely inserted within the first end  23  of the grip  20 . 
         [0034]    With regard to  FIGS. 5A through 5C , there are illustrated a series of close-up side views showing the fitting along with a partial length of the grip. The partial length of the grip is illustrated as a cutaway lengthwise cross section so as to show a chronological series of before, during, and after stages of fitting insertion into the grip. 
         [0035]    As shown in  FIG. 5B , the ramped surface  16  of the fitting first meets the outer edge of the interior seating surface  24 . Such outer edge of the interior seating surface  24  may be beveled to facilitate movement of retaining shoulder  17  through and over the entirety of the interior seating surface  24 . Here, it is also visible that the retaining shoulder  17  is sized with an outer dimension slightly larger than the inner dimension of the interior seating surface  24 . 
         [0036]    It should be understood that the material from which the grip is fabricated will have elastic qualities such that the interior seating surface  24  will expand to allow the retaining should  17  to ride over it, but snap back into place once the retaining shoulder  17  is completely through and past the interior retaining surface  24 . This snap-fit action results in the configuration seen in  FIG. 5C . Here, the interior seating surface  24  is shown abutting the exterior seating surface  11  of the fitting. Likewise, the annular lip  29  of the grip is shown abutting the shoulder surface  13  which effectively permanently retains the fitting within the grip. Moreover, in such configuration shown, each keyway boss  28   a - 28   c  and each corresponding keyway recess  19  interlock with one another upon abutment of the interior seating surface  24  with the exterior seating surface  11  so as to preclude rotational movement between the grip and the fitting. In this manner, both rotational and axial movement of the fitting within grip is prevented as the two are locked into place. 
         [0037]      FIG. 6  illustrates a side view of the complete flexible tapered grip assembly taken along line  6 - 6  of  FIG. 3 . Here, the invention is shown after the fitting is snap-fit into the grip and after the fitting is threaded to a coupling mechanism  40  and length of tubing  30 . In particular, it should be noted that the fitting includes barbs  12   a,  or some suitable structure, which retain the length of tubing  30  upon the fitting. The tubular interior  25  of the grip itself is also suitably larger than the outer diameter of the tubing  30  so as to allow both unrestricted movement of the tube and yet still allow the grip to function as a strain relief boot with integrated fitting for hydraulic connections. Thus, the present invention is a dual purpose strain relief boot and a grip for manual manipulation of a coupler (e.g., gladhand). Likewise, the space provided between the tubular interior  25  and the outer diameter of the tubing  30  also enables a coil spring (not shown) to be inserted over the tubing  30  all the way up to the fitting, further enhancing flexibility of the inventive assembly. 
         [0038]    The strain relief aspect of the present invention also provides an “anti-kinking” characteristic such that the tubing attached to the fitting through the tapered grip section is precluded from kinking. Unrestricted movement of the tube within the grip at the end opposite the fitting occurs only to a point at which bending of the given tube will result in the tube coming into contact with the sidewall of the grip. Due to the tapered nature of the grip, the ability of the grip to bend along with the tube is a function of the thickness of the grip. The thinner end will therefore bend along with the abutting tube in a manner that is proportional with the varied thickness of the grip wall. This tapering provides flexible support of the tube while inhibiting the ability of the tube to kink. This is effective against kinking that may otherwise (in the absence of the present invention) occur during the time of connection or at the time of operation (e.g., during a turning of the tractor cab relative to the trailer). Elongation of the grip may be provided so as to further enhance the anti-kinking characteristics of the present invention. In such elongation instance, the grip may be provided in successively tapering sections interconnected to one another. 
         [0039]    It should therefore be understood that the sidewall of the flexible tapered grip decreases in thickness along the substantially tubular interior from fitting end to a tear-resistant rail end, so as to oppose kinking of the tube during installation and operation. Moreover, the tear-resistant rail engages with the tube upon minimal bending radius, so as to provide freedom of movement of the tube during initial bending. Thus, the opposing of kinking of the tube is an increasing function of the decrease in thickness from fitting end to rail end and elongation of the flexible tapered grip. In this manner, the grip is elongated along the tube so as to increase anti-kinking characteristics of the overall grip and fitting assembly relative to the tube. 
         [0040]      FIG. 7  is provided so as to more clearly illustrate the details of the internal keyway boss structures. Here, a close-up view of the flexible tapered grip assembly according to the present invention shows the grip and fitting sections disconnected and the grip section partially cutaway to reveal the internal keyway bosses  28   a,    28   b.  Though three exist, it should be readily apparent that due to the cutaway aspect of  FIG. 7  only two are shown. From this figure, it should be readily apparent that each keyway boss is formed integrally with the grip as part of the sidewall of the tubular interior  25 . Moreover, the keyway boss has a surface that is collinear with the interior seating surface  24 . Thus, the keyway boss structures are internal and integral with the unitarily formed grip. 
         [0041]    In terms of implementation and use of the present invention, when used in conjunction with the all brass, corrosion-resistance fittings of the present invention, the grip and fitting assembly of the present invention provides improved bend and kink resistance during installation, operation, and gladhand connections and disconnections. Specifically, the present invention provides an improved thermo-composite flexible tapered grip and fitting design, the grip having increased thickness at the fitting end tapering to a tear-resistant rail at the hose and tube end of the fitting. The flexible tapered grip and grip fitting of the present invention further simplifies manufacture of the grip fitting assembly reducing cost and providing for longer operational life under bending and kinking. 
         [0042]    While the foregoing description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiments and examples herein. The above-described embodiments of the present invention are intended to be examples only. Alterations, modifications and variations may be effected to the particular embodiments by those of skill in the art without departing from the scope of the invention, which is defined solely by the claims appended hereto. 
         [0043]    The invention is therefore not limited by the above-described embodiments and examples, or embodiments and applications within the scope and spirit of the invention claimed as follows.