Abstract:
A hydraulic hose coupling, and method of assembling a coupling to a hydraulic hose are disclosed. The hydraulic hose and coupling assembly is designed to attach a coupling to a hydraulic hose in a no-skive fashion. Moreover, it does so with greatly enhanced sealing and retention capabilities relative to the currently available products. This is accomplished in many ways, some of which include the provision of a plurality of hose retention and sealing zones within the coupling, each of which include various combinations of radially inwardly directed barbs and radially inwardly and outwardly directed surface features on the inner stem of the coupling. With specific regard to the zone primarily directed to sealing, it includes a radially inwardly directed barb which works in conjunction with a straight cylindrical surface flanked by first and second radially inwardly directed recesses. But providing such structure, the inner liner of the hydraulic hose is compressed to a degree greater than any other zone, but at the same time mechanical strain in the liner is relived through the use of such recesses. Moreover, by providing barbs which are longer and more narrow in the first and second zones, the first and second zones provide improved retention capability. This is in combination with the surface features of first and second zones working in concert with the longer, narrower barbs to cause enhanced wire deflection and thus greater retention strength.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a non-provisional patent application claiming priority under 35 USC §119(e) to U.S. Provisional Patent Application No. 61/361,672 filed on Jul. 6, 2010. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure generally relates to hydraulic hoses and, more particularly, relates to couplings for hydraulic hoses. 
       BACKGROUND 
       [0003]    Many earth moving vehicles use pressurized hydraulic fluid as a mechanism for performing work. For example, with a motor grader, an earth-engaging blade downwardly depending from a main frame may be lifted, rotated and tilted using hydraulic cylinders; while with an excavator, a boom arm may be articulated with first and second hinged arms and a bucket at the terminus thereof, each being associated with a hydraulic cylinder to effect movement. Another example is a loader, wherein a lift arm hinged to the loader has a rotatable bucket or other implement hinged to an end of the lift arm. A lift cylinder may be associated with the lift arm and a tilt cylinder may be associated with the bucket or implement. When it is desired to lift the arm, the hydraulic fluid is directed to the lift cylinder, and when it is desired to rotate the bucket or implement, hydraulic fluid may be directed to the tilt cylinder. 
         [0004]    In order to control cylinders on each of the afore-mentioned vehicles and other hydraulically powered machines, hydraulic hoses are connected between the hydraulic pumps and the cylinders. The pumps are driven by the engine, typically diesel engine, of the earth moving vehicle. The hoses are typically reinforced hoses in that they have an inner elastomeric liner, a reinforcing layer surrounding the inner elastomeric layer, and an outer elastomeric cover surrounding the reinforcing layer. The elastomeric liner is flexible to enable motion between the cylinders and the pump and various moving parts on the earth moving vehicle. The liner is reinforced, typically with metallic wires or braids so as to be able to contain the significant pressures exerted by the hydraulic fluid being traversed therethrough. In addition, the elastomeric cover is provided around the reinforcing layer to protect the hose from ambient conditions, abrasions, and the environment. 
         [0005]    Such hydraulic hoses terminate in couplings enabling the hose to be connected to the hydraulic pump, the hydraulic cylinder, or other elements needing hydraulic pressure provided on the earth moving vehicle. Typically, such couplings include an inner stem which is inserted into the inner diameter of the hydraulic hose, and a ferrule or outer shell extending from the stem and spaced concentrically from the stem to provide a hose receiving space therebetween. The ferrule is then crimped towards the stem to compress the hydraulic hose towards the stem and frictionally hold it in place. The distal end of the stem can terminate in any number of different configurations including a hexagonal threaded nut, a flared coupling, an angled coupling, a male coupling, a female coupling, or the like. 
         [0006]    The aforementioned types of couplings are referred to as no-skive couplings in that the external layer of elastomeric material need not be removed prior to the attachment of the coupling. Rather the ferrule is in direct engagement with the outer elastomeric cover and through the use of sufficient teeth or serrations, a mechanical grip penetrates the elastomeric cover and engages the underlying reinforcing metallic layer. Alternatively, certain hydraulic hose couplings do in fact need to be skived, or in other words shaved, so as to remove the external elastomeric cover and expose the metallic reinforcing cover underneath. Only after the elastomeric cover is removed can such couplings then be mechanically coupled to the metallic layer. As such couplings require significant manual input, no-skive couplings have become the predominate player in the field of hydraulic hose couplings. 
         [0007]    While effective, users and manufacturers of such equipment are continually seeking improvements. Two areas which are currently less than optimum are the retention strength of the couplings on the hydraulic hose, and the seal provided between the coupling and the hose. As can be imagined, such hoses and the terminating couplings are often subjected to severe operating environments, pulling forces, and rotational torques. The couplings need to be able to withstand such motions repeatedly and under severe conditions. Not only must the coupling remain attached to the hose to thereby continue to communicate hydraulic fluid, but it must do so with no leakage of the hydraulic fluid. Accordingly, the seal between the coupling and the underlying hydraulic hose must remain intact throughout its work cycle. Any leak can, at the very least, result in less than optimal performance of the earth moving vehicle, or more problematically, can result in failure of the machine entirely. This not only can result in lost productivity, but as the hydraulic fluid is under extreme pressures can present a safety concern as well. 
       SUMMARY OF THE DISCLOSURE 
       [0008]    In accordance with one aspect of the disclosure, a hydraulic hose and coupling assembly is provided. The assembly may include a hydraulic hose and a coupling secured to the hydraulic hose. Hydraulic hose may include an inner elastomeric liner, a reinforcing layer comprised of a plurality of metallic wires surrounding the inner elastomeric liner, and an outer elastomeric cover surrounding the metallic reinforcing layer. An inner stem inserted into the hose and in engagement with the inner elastomeric liner, and an outer ferrule surrounding the outer elastomeric cover. The outer ferrule may include a plurality of radially inwardly extending barbs, the inner stem may include a plurality of radially inwardly directed recesses, and radially outwardly directed serrations, at least one of the barbs being aligned so as to be positioned toward the inner stem and being flanked by at least two of the recesses, and at least one of the barbs are being aligned so as to be positioned toward one of the serrations. 
         [0009]    In another aspect of the disclosure that may be combined with any of these aspects, the plurality of barbs are provided in first, second, third and fourth circumferential rows radially inwardly extending from the ferrule, and wherein the row of barbs aligned so as to be flanked by at least two recesses is the third row o barbs, and the row of barbs that are aligned with one of the radially outwardly protruding serrations of the inner stem is the first row of barbs. 
         [0010]    In another aspect of the disclosure that may be combined with any of these aspects, the third row of barbs includes tips having widths equal to about the width of two of the metallic wires, and heights equal to about the thickness of the hose cover plus one of the metallic wires. 
         [0011]    In another aspect of the disclosure that may be combined with any of these aspects, each of the recesses flanking the third row of barbs has a depth equal to about half the thickness of the liner. 
         [0012]    In another aspect of the disclosure that may be combined with any of these aspects, the distance between the third and fourth rows of barbs is about the width of eight of the metallic wires, the distance between the second and third row of barbs is equal to about the width of ten of the metallic wires, and the distance between the first and second rows of barbs is equal to about the width of ten of the metallic wires. 
         [0013]    In another aspect of the disclosure that may be combine with any of these aspects, the second row of barbs includes tips having widths equal to about the width of one of the metallic wires, and heights equal to about the thickness of the hose cover plus one and a half of the metallic wires. 
         [0014]    In another aspect of the disclosure that may be combined with any of these aspects, the second row of barbs is aligned with one of the radially inwardly extending recesses in the inner stem, and the recess aligned with the second row of barbs has a depth equal to about twenty percent of the liner thickness and a width equal to about three times the second row barb thickness. 
         [0015]    In another aspect of the disclosure that may be combined with any of these aspects, the first row of barbs includes tips having widths equal to about the width of one of the metallic wires, and heights equal to about the thickness of the hose cover plus two of the metallic wires. 
         [0016]    In another aspect of the disclosure that may be combined with any of these aspects, the serration aligned with the first row of barbs has a width equal to about three of the metallic wires. 
         [0017]    In another aspect of the disclosure that may be combined with any of these aspects, the fourth row of barbs includes tips having widths equal to about the width of three of the metallic wires, and heights equal to about the thickness of the hose cover plus one half of a metallic wire. 
         [0018]    In accordance with another aspect of the disclosure, a hose coupling is provided which may include an inner stem, an outer ferrule extending from the inner stem and being substantially concentric with the inner stem, a plurality of barbs radially inwardly extending from the outer ferrule toward the inner stem, a plurality of radially inwardly extending recesses in the inner stem, at least two of the radially inwardly extending recesses flanking at least one of the radially inwardly extending barbs, and a plurality of radially outwardly extending serrations in the inner stem, at least one of the radially outwardly extending serrations being aligned with at least one of the radially inwardly extending barbs 
         [0019]    In another aspect of the disclosure that may be combined with any of these aspects, the plurality of radially outwardly extending barbs include a first, second, third, and fourth row of barbs, wherein the first row of barbs are aligned with one of the radially outwardly extending serrations in the inner stem, and wherein the third row of barbs are aligned so as to be flanked by first and second radially outwardly extending recesses within the inner stem. 
         [0020]    In another aspect of the disclosure that may be combined with any of these aspects, the plurality of radially inwardly extending barbs include canted sides each having an angle relative to a longitudinal axis of the barbs of no more than fifteen degrees. 
         [0021]    In accordance with another aspect of the disclosure, a hydraulic hose and hose coupling assembly is provided with may comprise a hydraulic hose having a liner, a reinforcing layer on a cover, and a coupling secured to the hose. The coupling may have an inner stem and an outer ferrule, the stem may have a substantially cylindrical outer surface interrupted by a plurality of serrations and recesses, the outer ferrule having a plurality of barbs, at least one barb being aligned with one of the serrations, at least one of the barbs being aligned with at least one of the recesses, at least one of the barbs being aligned with a substantially cylindrical outer surface, and at least one of the barbs being aligned with the substantially cylindrical outer surface and being flanked by two of the recesses. 
         [0022]    In another aspect of the disclosure that may be combined with any of these aspects, the consecutive rows of circumferentially arrayed barbs are provided in first, second, third, and fourth rows, heights of the barbs decreasing from the first row to the fourth row, and the barbs have a tip width that increases from the second row to the fourth row. 
         [0023]    In another aspect of the disclosure that may be combined with any of these aspects, a first zone may extend between the first row and the second row, a second zone may extend between the second row and the third row, a third zone may extend between the third row and the fourth row, and a fourth zone may extend after the fourth row, wherein the width of the zones decreases from the second zone to the third zone, the wire deflection decreases from the first zone to the fourth zone, and the amount of liner compression increases from the first row to the third row and decreases from the third row to the fourth row. 
         [0024]    In accordance with yet another aspect of the disclosure, a method of assembling a coupling to a hydraulic hose is provided which may comprise inserting a coupling into a hydraulic hose wherein the hydraulic hose has an inner elastomeric liner, a reinforcing layer surrounding the elastomeric liner, and an elastomeric cover surrounding the reinforcing layer. The coupling may have an inner stem and a surrounding ferrule with hose retention and sealing space therebetween. The method further includes crimping the ferrule toward the stem wherein a plurality of barbs extend from the ferrule and penetrate the cover to engage the reinforcing layer, a plurality of recesses and serrations extending from the inner stem to receive and penetrate the liner, respectively, and the plurality of barbs, recesses, and serrations form a plurality of hose retention and sealing zones. The method may further include relieving strain in the liner within the hose retention and sealing zone having the highest level of liner compression while aligning the barbs within the zone having the highest level of liner compression with a cylindrical surface of the inner stem and flanking the cylindrical surface with first and second recesses. 
         [0025]    In another aspect of the disclosure that may be combined with any of these aspects, the method may further include providing the plurality of barbs in first, second, third and fourth rows of circumferentially arrayed barbs, the first row of barbs compressing the reinforcing layer against a first serration such that the reinforcing layer has a thickness less than the thickness of the reinforced layer prior to assembly, and the method may further include providing the reinforcing layer with a plurality of metallic wires, and the crimping may cause the wires to deflect the most within a first hose retention and sealing zone between the first and second rows of barbs, second most within a second zone between the second row and the third row of barbs, third most within a third zone between the third row and fourth row of barbs, and least within a fourth zone after the fourth row of barbs. 
         [0026]    In another aspect of the disclosure that may be combined with any of these aspects, the method may further include positioning the barbs, recesses, and serrations such that the liner compresses the most in the third zone, second most in the fourth zone, third most in the second zone, and the least in the first zone. 
         [0027]    In accordance with another aspect of the disclosure, a hydraulic hose and coupling assembly is provided which may include a hydraulic hose having a liner, reinforcing layers surrounding the liner, and a cover surrounding the reinforcing layer, and a coupling secured to the hydraulic hose and having a proximal end adjacent to an opening in the hydraulic hose and a distal end further removed from the hydraulic hose opening then the proximal end. The coupling may include an inner stem and a surrounding ferrule defining hose retention and sealing space into which the hydraulic hose is maintained and sealed. The inner stem and surrounding ferrule may have surface features defining a plurality of hose retention and sealing zones, the plurality of hose retention and sealing zones each having a Menor Factor. The Menor Factor in each zone decreasing from the proximal end to the distal end. 
         [0028]    These and other aspects and features of the disclosure will be more readily understood upon reading the following detailed description when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0029]      FIG. 1  is a perspective view of a hydraulic hose and coupling assembly constructed in accordance with the teachings of the disclosure; 
           [0030]      FIG. 2  is a cutaway view of the hose of  FIG. 1 ; 
           [0031]      FIG. 3  is a cross-sectional view of the hose and coupling assembly of  FIG. 1  taken along line  3 - 3  of  FIG. 1 ; 
           [0032]      FIG. 4  is a cross-sectional view of the hose coupling without the hose attached; 
           [0033]      FIG. 5  is a cross-sectional view of an alternative embodiment of the hose coupling and hose prior to crimping; and 
           [0034]      FIG. 6  is a cross-sectional view of the alternative embodiment of the hose coupling and hose of  FIG. 5 , but after crimping. 
       
    
    
     DETAILED DESCRIPTION 
       [0035]    Referring now to the drawings, and with specific reference to  FIG. 1 , a hydraulic hose and coupling assembly constructed in accordance with the teachings of this disclosure is generally referred to by reference numeral  20 . It is to be understood that the hose and coupling assembly  20  depicted is but one example and that the teachings of the present disclosure are equally applicable to hoses and couplings of different shapes and configurations as well. 
         [0036]    The hose and coupling assembly  20  includes a length of hydraulic hose  22  having distal and proximal ends  24  and  26 . To the distal end  24  is attached a first coupling  28  and to the proximal end  26  a second coupling  30  is attached. As shown, each coupling  28  and  30  may include an inner stem  32  from which extends an outer shell or ferrule  34 . At the juncture between the ferrule and the stem, a hexagonal or otherwise suitable wrenching surface  36  can be provided to facilitate attachment of the hose  22  to a pump  38 , cylinder  40 , or other element of an earth moving vehicle (not shown) needing hydraulic power. The coupling may further include a rotatable nut  42  for threaded attachment to the pump, cylinder or the like. Moreover, as indicated above, the coupling need not include the nut  42  as shown, but rather could be provided in the form of a flared coupling, a female coupling, or an angled coupling among others. 
         [0037]    Referring now to  FIG. 2 , a detailed cut-away view of an exemplary hose  22  is shown in more detail. As shown, the hose  22  may include an inner liner  44 , surrounded by a reinforcing layer  46 , which in turn is surrounded by an elastomeric outer cover  48 . The elastomeric inner liner  44  provides a fluid tight conduit for communicating hydraulic fluid through the opening defined by inner diameter  50 . The liner  44  may be manufactured from flexible elastomeric materials to enable the hydraulic fluid to be communicated while the earth moving vehicle is moved, the cylinder is moved, and/or the other moving parts of the vehicle are differently positioned. The reinforcing layer  46  may be provided in the form of a plurality of metallic wires or braids surrounding the inner elastomeric liner  44 . The reinforcing layer  46  is used to provide sufficient radial strength to the hose so as to contain the hydraulic fluid being communicated therethrough. For example, such hydraulic fluids are often times communicated in excess of thousands of PSI which the elastomeric liner by itself would not be able to contain. Moreover, governmental regulations dictate that such hose be built to withstand significantly greater pressure than the actual working pressure of the hydraulic fluid, and thus the reinforcing layer allows that requirement to be met. For example, such hose is typically required to have a burst pressure (i.e. the minimum pressure at which the tube will burst apart), which is at least four times greater than the average working pressure of the hydraulic fluid. Finally, the outer elastomeric cover  48  is also manufactured from a flexible material such as a rubber or polymeric material similar to that from which the inner liner  44  is manufactured. The cover  48  allows the hose  22  to maintain its flexibility while also protecting the reinforcing layer  46  and inner liner  44  from the ambient conditions, abrasion, and other environmental conditions. 
         [0038]    Referring now to  FIGS. 3 and 4 , the interaction between the hose  22  and coupling  28  is shown in greater detail. As mentioned above, the present disclosure is directed to a no-skive coupling in that the outer cover  48  remains intact when the coupling  28  is attached to the hose  22 . In accordance with the present disclosure, it is able to do so based on the structure set forth in  FIGS. 3 and 4 . 
         [0039]    Starting with  FIG. 4 , it shows the inner stem  32  and outer ferrule  34  in cross-sectional detail. The inner stem  32  includes a cylindrical inner diameter  52  and an outer diameter  54  with a plurality surface features  56  designed to facilitate the retention and sealing of the hose  22  relative to the coupling  28 . Those surface features  56  may include a plurality of radially outwardly extending serrations  58 , a plurality of radially inwardly extending recesses  60  and a plurality of straight cylindrical surfaces  62 . 
         [0040]    With respect to the outer ferrule  34 , it includes an outer cylindrical wall  64  substantially concentric with the inner stem  32 . The outer surface  66  of the wall  64  may be substantially cylindrical but radially inwardly extending from the outer wall  64  are provided a plurality of barbs  68 . In the depicted embodiment, first, second, third, and fourth rows of barbs  70 - 76  are provided with specific dimensions and spacing both relative to each other and relative to the surface features  56  to enhance the hose retention and sealing features identified above. 
         [0041]    Starting with the first barb  70 , while not easily discernable from the sectional views of  FIGS. 3 and 4 , it is to be understood that the barb  70  is in fact circumferential in that it extends around the entire inner diameter of the outer wall  64 . In cross-section, it can be seen to include a barb height  78  extending from the inner surface  80  of the cylindrical wall  64  to the outer tip  82  of the barb  70 . First and second canted side walls  84  and  86  extend from the inner surface  80  to the outer tip  82  at an angle  88  selected so as to enable the barb  70  to easily penetrate the outer cover  48  when the coupling  28  is attached to the hose  22 . The angle  88  may be provided at fifteen degrees relative to a longitudinal axis  90  of the barb  70  or other embodiments could be provided within plus or minus five degrees of such angle. With respect to the outer tip  82 , it is also of a specific dimension relative to the size of the wires  92  forming the reinforcing layer  46 . More specifically, the outer tip  82  of the first barb  70  may be provided with a width equal to approximately one of the reinforcing wires  92 . By providing such a slim profile, the tip  82  is able to easily penetrate not only the outer cover  48  but the reinforcing layers  46  as will be described in further detail herein. 
         [0042]    Opposite the first barb  70  is a serration  94  which, as indicated above, is a surface radially extending away from the outer diameter  54  of the stem  32 . The serration  94  is not only provided directly across and in alignment with the first barb  70  but is provided with a specific size and shape as well. More specifically, the serration  94  may be provided with a width of approximately three of the reinforcing wires  92 . 
         [0043]    Moving on to the second barb  72 , it is of a similar profile to the first barb  70  in the sense that it is circumferential and provided with first and second canted walls  96  and  98 . Moreover, it includes an outer tip  100  again having a width of approximately that of one of the reinforcing wires  92 . Opposite to the second barb  72  is a recess  102  which radially inwardly extends from the outer diameter  54  of the inner stem  32 . The recess  102  may be about three times the width of the outer tip  100  and includes a depth  106  equal to approximately twenty percent of the thickness of the liner  44 . The second barb  72  has a height  107  less than the first barb  70 . 
         [0044]    With respect to the third barb  74 , it again includes canted walls  108  and  110  and an outer tip  112 , but the outer tip  112  is approximately twice as wide as the tips of the first and second barbs  70  and  72 . More specifically, the outer tip  112  may be approximately the width of two of the reinforcing wires  92 . The third barb  74  may include a barb height  114  less than the second barb  72  and roughly equal to the thickness of the cover  48  plus one of the reinforcing wires  92 . Aligned with, and opposed to, the outer tip  112  is a straight cylindrical surface  116  which in turn is flanked by first and second recesses  118  and  120 . The straight cylindrical surface  116  has a width  122  approximately equal to four of the reinforcing wires  92 , while the recesses  118  and  120  include a depth equal to approximately half the thickness of the liner  44 . 
         [0045]    Finally, with respect to the fourth barb  76 , it also includes first and second canted walls  126  and  128  which terminate in an outer tip  130 . The outer tip  130  may include a width equal to approximately two of the reinforcing wires  92 . Opposite to, and aligned with, the outer tip  130  is a second straight cylindrical surface  132  which extends from the second flanking recess  120  to the distal end  134  of the coupling  28 . 
         [0046]    In providing the barbs  68  and surface features  56  in aligned pairs, it will be noted that the hose and coupling assembly  20  provides a plurality of hose retention and sealing zones  136 , each of which is designed to optimize the hose retention and sealing capabilities of the assembly as will be described in further detail herein. Starting with first zone  138 , it is defined herein as extending from the alignment of the first barb  70  and the serration  94  to the beginning of the second barb  72 . In fact, the first barb  70  and second barb  72  are specifically spaced apart to define the length of the first zone  138 . That distance  139  is approximately the width of ten of the reinforcing wires  92 . 
         [0047]    A second zone  140  extends from the second barb  72  to the beginning of the third barb  74 . The second zone length is defined by the distance  142  between the first and second barbs which may be provided again at a width of approximately ten of the reinforcing wires  92 . 
         [0048]    A third zone  144  extends from the third barb  74  to the fourth barb  76  with a distance  146  defining the zone  144  and being of a width approximately equal to eight of the reinforcing wires  92 . 
         [0049]    Finally, a fourth zone  148  extends from the fourth barb  76  to the distal end  134 . 
         [0050]    A significance of the hose retention and sealing zones  136  is that each zone is optimized so as to be primarily directed to hose retention, hose sealing, and transitions therebetween. In order to do so, the barbs and surface features cooperate so as to penetrate the cover to varying degrees, deflect the reinforcing wires to various degrees, and compress the liner to varying degrees as well. More specifically, the first zone  138  is primarily directed to retaining the hose  22  within the coupling  28 . Accordingly, the barb  70  as indicated above is provided with a finely dimensioned tip  82  designed not only to easily penetrate the cover  48  but also more easily penetrate the reinforcing wires  92 . In so doing, it can be seen from  FIG. 3  that the wires  92  deflect more in the first zone  138  than in any of the other three zones. By so penetrating the metallic reinforcing wires  92  with the metallic barb  70 , the retention of the coupling  28  on the hose  22  is greatly enhanced. Moreover, the surface feature  56  provided within the first zone  138  is in fact a serration  94  which extends from the straight cylindrical surface of the stem  32  so as to limit the space between the outer tip  82  and surface feature  56  when crimped. This in turn facilitates deformations of the wires  92  as shown. This also is not detrimental to the sealing capability of the assembly  20  in that latter zones are tasked with the primary function of sealing the coupling  28  to the hose  22 . 
         [0051]    Moving on to the second zone  140 , it serves as a transition zone between the wire retention features of the first zone  138  and the sealing features of the third zone  144 . In so doing, it serves as both a retention zone and a sealing zone. With respect to retention, the outer tip  100  is provided with the same fine width as the first zone  138  so as to enable easy penetration of the outer cover  48  and disturbance of the metallic wires  92 . However, it will be noted that the second zone  140  includes a recess  102  as its surface feature  56  and thus while the width of the tip  100  would allow for the same ease of penetration into the wires  92  as the first zone  138 , the added dimension between the tip  100  and the recess  102  causes the tip  100  not to penetrate the wires  92  to the same degree as the first zone  138 , thereby providing greater deformation in the liner  44  to facilitate sealing. However, given the smaller dimension of the outer tip  100 , some degree of wire deflection is noticeable in the second zone  140 , although not of the same degree as the first zone  138 . 
         [0052]    With respect to the third zone  144 , it serves as the main sealing zone of the assembly  20 . Penetration of the wires  92  is not of as much significance as with the first and second zones, and thus it will be noted that its outer tip  112  is substantially wider than the tips of the first and second barbs  70  and  72 . However, third zone  144  has significantly different surface features  56  provided in the adjacent and aligned section of the inner stem  32 . More specifically, a recess is not provided directly adjacent or aligned with the outer tip  112 , but rather a straight cylindrical surface  116  is, thereby providing a relatively small dimension between the two elements when the coupling  28  is crimped onto the hose  22 . However, as this may result in significant strain within the liner  44 , the straight cylindrical surface  116  is flanked by first and second recesses  118  and  120 . In other words, when the third barb  74  compresses toward the straight cylindrical surface  116 , this compresses the inner liner  44  to the highest level of any of the three zones thereby providing maximum sealing capability. However, in order to relieve the mechanical strain induced in the liner  44  and thereby elongate the serviceable life of the elastomeric liner (i.e. avoiding cracking or other physical deformation of the liner), the flanking recesses  118  and  120  provide additional space into which the material of the liner  44  can be moved to thereby absorb some of that compression and thereby relieve some of the strain within the liner  44  directly between the outer tip  112  and straight cylindrical surface  116 . 
         [0053]    Finally, with respect to the fourth zone  148 , it also serves as a transition zone but one between the sealing function of the third zone  144  and the distal end  134  of the coupling  28 . This area eases the hose from the slight wire deflection at the beginning of the fourth zone  148  and slight liner compression at the beginning of the fourth zone  148  to the uncrimped state at the end of the fourth zone  148  proximate the distal end  134 . In so doing, the delta force to which the hose is subjected inside and outside the coupling is minimized. A final shell barb  150  is provided at the distal end  134 . 
         [0054]      FIGS. 5 and 6  depict an alternative embodiment of the present disclosure. The alternative embodiment is identical to the first embodiment but for replacing the serration  58  with a recess  152 , and removing the final shell barb  150  entirely. The recess  152  includes a depth equal to about three times the width of the outer tip  82  of first barb  70  adjacent thereto. The final shell barb  150  is removed to better transition liner compression through the fourth zone  148 , and provide a slightly less tight crimping diameter. 
         [0055]    Based on the foregoing, it can be seen that the hose and coupling assembly  20  provides a vastly improved structure and method for attaching a coupling to a hydraulic hose. The barbs and surface features are designed and oriented so as to maximize the hose retention and sealing features of the assembly, while still maintaining the required inner diameters and outer diameters dictated by the users of such couplings. Moreover, while the foregoing has been made with reference to specific dimensions, angles, and relative proportions of the pieces in terms of ratios, the inventors have created a specific factor which can be used to manufacture a coupling and hose and coupling assembly which provides for enhanced hose retention and sealing capability. That factor, known herein as the Menor Factor (abbreviated F M ), incorporates and takes into account many of the foregoing features identified above, including, the degree of wire deflection in the reinforcing wires  92  (abbreviated herein as W D ); the degree of compression of the inner liner  44  (herein abbreviated as L C ), the height of each of the barbs (hereinafter abbreviated B H ); the width of the barb tips (herein abbreviated as T W ); and the width of each of the zones (hereinafter abbreviated as Z W ). 
         [0056]    Taking each parameter into account, the Menor Factor can be mathematically represented by the following equation: 
         [0000]        F   M   =W   D   /L   C +( B   H )( T   W )+½ Z   L ;
       wherein F M  equals the Menor Factor;   W D  equals wire deflection;   L C  equals liner compression;   B H  equals barb height;   T W  equals tip width; and   C L  equals zone length.       
 
         [0063]    From the foregoing, it can be seen that the teachings of the present disclosure can be used to manufacture a hose coupling and hydraulic hose and coupling assembly with greatly improved hose retention and sealing capability relative to prior art designs. 
       INDUSTRIAL APPLICABILITY 
       [0064]    In general, the technology disclosed herein has industrial applicability in a variety of settings such as, but not limited to, earth moving vehicles employing hydraulic power and cylinders. In such applications, pressurized hydraulic fluid needs to be communicated from a pump or pumps to a cylinder or cylinders to perform useful work. Such hydraulic fluid is carried by a hydraulic hoses terminating in couplings for attachment to the pump, cylinder, or the like. In such applications, it is imperative that the coupling remains attached to the hose and sealed thereto. The present disclosure is able to do so through the unique incorporation of a variety of novel features, some of which are reiterated below. 
         [0065]    In order to retain the coupling most advantageously onto the hose, the coupling is provided with a series of radially inwardly directed barbs of varying height and width. By varying the heights with the longest barb being provided closest to the proximal end of the coupling and the shortest barb being provided closest to the distal end of the coupling, it is ensured that the first row of barbs penetrates the outer cover of the hose to the greatest degree, and more importantly for purposes of retention, penetrates the reinforcing wires to the greatest degree thereby causing a greatest degree of wire deflection. 
         [0066]    Moreover, to facilitate the deformation of the wires, the tips of the first and second row of barbs are provided with the smallest width dimension of the tips, and which then increases as the barbs approach the distal end of the coupling. This again facilitates penetration of the wires, and deflection of same. 
         [0067]    Concomitantly with the width and height of the barbs, the inner stem is provided with a plurality of surface features to augment the performance of the barbs. More specifically, as it is a goal of the first and second zones to primarily be directed to retaining the coupling on the hose, and for the third and fourth row of barbs and zones to seal the hose relative to the coupling, the surface features provided on the inner stem are varied as well. 
         [0068]    In order to ensure the greatest degree of wire deflection in the first zone, not only is the barb shaped as indicated above, but aligned with that first barb is a serration which radially outwardly extends from the first stem. This in turn reduces the overall dimension between the serration and the tip thereby limiting the room into which the wire and elastomeric material can be forced, in so doing, the wires are caused to radially outwardly deflect into the first zone thus enhancing the retention capability of the first zone. The same is somewhat true with respect to the second barb in that it is dimensioned with a tip of the same width, but as will be noted and was discussed above, opposite to the second barb, is provided a recess not a serration. This therefore forms an advantageous transition zone between the first zone and the third zone, wherein the second zone provides somewhat less retention capabilities but somewhat increase sealing capabilities. In so doing, it can be seen from the above figures that the wire deflects to a significant degree in second zone but not as much as in the first zone. Conversely, the liner compresses to a greater degree in the second zone relative to the first zone. 
         [0069]    In order to provide the improved sealing capabilities of the present disclosure, the third zone provides a unique combination of barb geometry and inner stem surface features. More specifically, the barb is provided with a slightly wider tip dimension and shorter height dimension so as to not penetrate the outer cover to the same degree and not to penetrate the reinforcing wires. Accordingly, it will be noted that the wire deflection in the third zone is thus greatly diminished. However, the third barb works in conjunction with the surface features aligned therewith, namely a central straight cylindrical section flanked by first and second recesses. The flat cylindrical section provides a surface against which the widened third barb can compress to thereby compress the liner and provide the greatest degree of sealing capability in the third zone. However, by compressing the liner to such a degree to reach the desired sealing capabilities, significant mechanical strain is generated within the material of the liner itself which, but for the novel contributions of the present inventors, could result in cracking of the elastomeric material over time. However, the inventors have cleverly provided flanking recesses about that straight cylindrical surface so as to relieve the mechanical strain within the liner while at the same time allowing the compression of the liner to be maintained at a sufficiently high level to reach the sealing capability desired. 
         [0070]    Finally, the fourth zone provides a transition between the sealing features of the third zone to the distal end of the coupling. As the distal end of the coupling will be the area of the hose and coupling assembly subjected to the greatest mechanical forces as the hose moves, is angled, reciprocates, and otherwise endures the motions required by the earth moving vehicle, the inventors have provided a relatively long fourth transition zone to, on the one hand, protect the sealing capabilities of the third zone, while on the other hand allow for the increased range of motion encountered by the fourth zone. 
         [0071]    From the foregoing, it can be seen that the teachings of the present disclosure can be used on any hydraulic system employing hydraulic hoses and couplings including earth moving vehicles such as, but not limited to, loaders, excavators, track type tractors, rippers, pipe layers, trucks, scrappers, compactors, skid steers, harvesters, graders, lift trucks, and the like.