Abstract:
A crown seal for sealing between the body of a female hydraulic coupling member and the probe section of male hydraulic coupling member has sealing projections on or near its outer diameter to provide enhanced sealing effectiveness between the crown seal and the body of the female member and obviate the need for circumferential O-ring seals. In a first embodiment, the sealing projections have a substantially circular cross section and project both axially and radially from the body of the crown seal. In a second embodiment, the sealing projections have a semicircular cross section and project in an axial direction from certain outside edges of the crown seal. Crown seals according to the invention may be retrofitted to female hydraulic couplings of the prior art. Alternatively, the body of the female coupling or a seal retainer or seal cartridge fitted therein may be provided with grooves or contoured surfaces to fit the sealing projections on the crown seal.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    NONE 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    NOT APPLICABLE 
       BACKGROUND OF THE INVENTION 
       [0003]    1. Field of the Invention 
         [0004]    This invention relates to hydraulic couplings for subsea use. More particularly, it relates to polymeric crown seals for sealing between the body of a female hydraulic coupling member and the probe of a male hydraulic coupling member inserted into the receiving chamber of the female member. 
         [0005]    2. Description of the Related Art including information disclosed under 37 CFR 1.97 and 1.98. 
         [0006]    Subsea hydraulic couplings generally consist of a male member and a female member having seals designed to seal the junction between the male and female members. The female member generally has a cylindrical body with a relatively large diameter bore at one end and a relatively small diameter bore at the other. The smaller bore facilitates connections to hydraulic lines, while the larger bore contains the seals and receives the male portion of the coupling. The male member includes a probe section insertable into the large bore of the female member. According to various embodiments of the device, the seals either abut the end, or face, of the male member or engage the male member about its outer circumference. Hydraulic fluid is then free to flow through the female and male portions of the coupling and seals prevent that flow from escaping about the joints of the coupling. 
         [0007]    Optionally, a check valve may be installed in the female member and also in the male member. Each check valve is open when the coupling is made up; however, each check valve closes when the coupling is broken so as to prevent fluid from leaking out of the system of which the coupling is part. 
         [0008]    In U.S. Pat. Nos. 4,694,859 and 5,762,106 to Robert E. Smith III, an undersea hydraulic coupling and metal seal are disclosed. A reusable metal seal engages the circumference of the probe when it is positioned within the female member body. The seal is held in place by a cylindrical body or retainer. When the male and female portions of the coupling are parted under pressure, the retainer prevents the metal seal from blowing out through the bore of the female member. 
         [0009]    U.S. Pat. No. 4,900,071 to Robert E. Smith III discloses an undersea hydraulic coupling with an elastomeric seal that is restrained from radial movement into the central bore of the female member by a circumferential shoulder on one or both surfaces adjacent the seal. Preferably, the seal has a dovetail interference fit with one or both surfaces. U.S. Pat. Nos. 5,052,439, 5,099,882, 5,203,374 and 5,232,021 to Robert E. Smith III also show undersea hydraulic couplings with these seals. An inner cylindrical surface of the annular seal engages the circumference of the male member or probe as the probe is inserted into the female member. As the male member or probe is pulled out of the female member bore, the leading face of the male member reaches the soft annular seal intermediate that bore. When the face reaches the midpoint of the soft annular seal, the dovetail interference fit prevents the seal from imploding into the bore, as the seawater and/or hydraulic fluid enter the bore at high pressure. 
         [0010]    If the probe of the male coupling member is imperfectly aligned with the female coupling member, it can drag against the female coupling bore or receiving chamber, and drag against each seal retained in the bore. The drag can result in galling of the surfaces of the respective coupling members. The drag can also damage the seals retained in the female coupling member, especially pressure-energized radial metal seals that seal around the circumference of the male coupling member. 
         [0011]    To help align the male coupling member when it enters the female bore or receiving chamber, some undersea hydraulic couplings include two or more redundant radial seals. Two or more seals provide guide points to help the male member enter the bore or receiving chamber without galling and damage to the sealing surfaces. Additionally, two or more redundant seals reduce the risk that hydraulic fluid will leak from the coupling at higher pressures and greater undersea depths. 
         [0012]    U.S. Pat. No. 6,575,430 to Robert E. Smith III discloses an undersea hydraulic coupling member having a ring-shaped seal with multiple sealing surfaces which extend radially inwardly into the receiving chamber of the female member. The multiple sealing surfaces help guide the probe of the male coupling member into the female member without the risk of drag or galling of the receiving chamber or metal seal retained therein. The seal has an interference fit with reverse inclined shoulders in the female member to restrain the seal from moving radially inwardly due to vacuum or low pressure such as may be produced by the withdrawal of the male probe. 
         [0013]    The crown seal disclosed in U.S. Pat. No. 6,575,430 provides an undersea hydraulic coupling with a ring-shaped polymeric seal having two or more radial sealing surfaces at the inner circumference thereof. Each of the sealing surfaces at the inner circumference engages the probe of the male coupling member, providing guide points to help ensure proper alignment between the coupling members, prevent or reduce the risk that the male coupling member will drag against the female coupling member during engagement or disengagement, and prevent or reduce the risk of galling of the surfaces and seals retained therein. 
         [0014]    On each side of the polymeric seal, opposing inclined circumferential shoulder surfaces have an interference fit with the seal and prevent the seal from imploding and/or radially moving into the bore especially upon separation of the female member and male member. The seal has inclined surfaces that have an interference fit with the opposing inclined shoulder surfaces. 
         [0015]    A coupling of the prior art first disclosed in U.S. Pat. No. 6,575,430 is shown in  FIG. 1 . Female member  20  comprises body  21 , handle  48  which may be threaded to a manifold plate, and central bore  32  which has several variations in its diameter as it extends through the female member. The first end of the bore may be internally threaded for connection to a hydraulic line. A cylindrical passageway extends longitudinally within the female member body and terminates at valve seat  27 . Adjacent valve seat  27  is shoulder  33  which forms one end of receiving chamber  34 . 
         [0016]    In the illustrated coupling member, the receiving chamber (which receives the probe of the male member) has a stepped internal diameter with internal shoulders  33 ,  35  and  63 . The receiving chamber has a first smaller diameter  34  and a second larger diameter  47 . 
         [0017]    In the illustrated coupling, the female member includes poppet valve  28  which is slidably received within the cylindrical passageway. The poppet valve is conical in shape and is urged by valve spring  41  into a seated position against valve seat  27 . When the poppet valve is in a closed position against the valve seat, it seals fluid from flowing between the male member and the female member. Hollow spring collar  42  anchors the valve spring  41  and is held in place by a collar clip. Actuator  44  extends from the apex of the poppet valve. A corresponding valve actuator in the male member contacts actuator  44  to open valve  28  upon coupling makeup. 
         [0018]    Ring shaped seal  70  is positioned in the receiving chamber of the female member. The ring shaped seal is an elastomer or polymer seal that is flexible and resilient. As shown in  FIG. 2 , the seal has a first inclined shoulder surface  72  and a second inclined shoulder surface  71 . The axial thickness of the elastomeric seal at outer circumference  66  is greater than the axial thickness of the seal at inner circumference  73 . The seal has a generally wedge-shaped cross section. The seal has at least two radial sealing surfaces  75 ,  76  extending inwardly from the seal&#39;s inner circumference  73 . Each of the radial sealing surfaces extends radially inwardly from the inner circumference to engage the probe of the male member when the probe is inserted through the seal. Each of the radial sealing surfaces is elastically deformed by the probe when it is inserted through the seal. The two radial sealing surfaces provide guide points to help align and guide the probe when it is inserted through the seal into the receiving chamber. The pair of radial sealing surfaces reduces or eliminates the problem and resulting damage from drag against the female bore and/or galling of the coupling surfaces and seal surfaces. 
         [0019]    In the coupling member shown in  FIG. 1 , the seal (shown separately in  FIG. 2 ) has grooves  77 ,  78  in its outer circumference. O-rings may be positioned in each of the grooves. In some versions, instead of grooves and O-rings, the seal has a plurality of integral projections which extend radially outwardly from the outer circumference. 
         [0020]    In the female coupling member illustrated in  FIG. 1 , the crown seal  70  is restrained from being imploded into the receiving chamber due to low pressure or vacuum because the seal has an interfit with reverse inclined shoulder surface  62  of seal retainer  29  and reverse inclined shoulder surface  61  of locking member  30 —a “dovetail interlocking seal.” The seal retainer may be a cylindrical sleeve that slides into the second diameter  47  of the receiving chamber. When the seal retainer is fully engaged with the female member, first end  46  of the seal retainer abuts shoulder  63 . The seal retainer holds hollow radial metal seal  31  on internal shoulder  35 . 
         [0021]    The seal retainer has a first internal circumferential surface  59  adjacent the first end thereof and a second internal circumferential surface  69  adjacent the second end thereof. The internal diameter of the first inner circumferential surface is smaller than the internal diameter of the second internal circumferential surface. Reverse inclined shoulder  62  is between the first and second internal circumferential surfaces. The reverse inclined shoulder has an interfit with seal  70  to restrain the seal from moving radially inwardly. O-ring  49  is positioned in a groove at the first end  46  of the seal retainer to provide a face-type seal between the seal retainer and shoulder  63 . 
         [0022]    Locking member (or “retainer nut”)  30  engages the female coupling member using threads  53  or other means. When the locking member is fully secured to the female coupling member, first end  64  abuts the seal retainer and holds the seal retainer in place. The locking member has an internal diameter  54  that allows insertion of the probe of the male member therethrough. Reverse inclined surface  71  holds seal  70  in place and restrains the seal from moving radially inwardly. 
         [0023]    The seal length may be chosen based on the length of the probe and/or the depth of the female receiving chamber. Greater spacing of the radial sealing surfaces helps align the male and female coupling members and avoid damage to the metal seal in the coupling. Radial sealing surfaces  75  and  76  extend inwardly from inner circumference  73 . Seal  70  is positioned on the second inner circumferential surface  69  of seal retainer  29 . Reverse inclined shoulder surfaces  71 ,  72  interfit with reverse inclined shoulder  61  of the locking member and reverse inclined shoulder  82  of the seal retainer. 
         [0024]    As shown in  FIG. 2 , the outer circumference of the seal has grooves  77 ,  78  for holding O-rings that seal with inner circumferential surface  69 . 
         [0025]      FIG. 1  shows a crown seal  70  installed in a seal retainer  29  held within the body of female coupling member  20 . However, other designs have also been used for holding the crown seal in place in the coupling member. For example,  FIG. 3  shows a crown seal  70  having a dovetail configuration in a seal cartridge. The seal cartridge may hold and secure a plurality of annular seals that may be removed from the coupling member together with the seal cartridge. The seal cartridge comprises a shell  80  that engages the coupling member and a seal carrier  81  that holds the annular seals. 
         [0026]    In the prior art coupling shown in  FIG. 3 , the shell is a generally ring-shaped body with an outer diameter that may have a threaded section  83  to engage the female coupling member. The shell has first end  84 , second end  85 , first larger inner diameter  86 , second smaller inner diameter  87 , and internal shoulder  88  between the first and second inner diameters. The shell also may include negative or reverse angle shoulder  89  that extends radially inwardly from internal shoulder  88 . Holes  90  may be included in the first end of the shell, and a spanner or other tool may be inserted into the holes to rotate the shell to engage or disengage it from the female member. 
         [0027]    The seal carrier  81  is a generally ring shaped sleeve, part of which engages or fits at least partially into the shell. The seal carrier has first end  91  which fits into the shell, second end  92 , first larger outer diameter  93 , second smaller outer diameter  94 , first larger inner diameter  95 , and second smaller inner diameter  96 . The seal carrier may have negative or reverse angle shoulder  97  between the first larger inner diameter and second smaller inner diameter. The seal carrier also may include outer shoulder  98  between the first larger outer diameter and the second smaller outer diameter. 
         [0028]    The first end of the seal carrier slides into the first larger inner diameter  86  of the shell. There may be little or no clearance between the second smaller outer diameter  94  of the seal carrier and the inner diameter  86  of the shell, or there may be a slight interference fit. When the first end of the seal carrier is fully inserted into the shell, the first end  91  may abut internal step  99  of the shell, and/or second end  85  of the shell may abut outer shoulder  98  of the seal carrier. 
         [0029]      FIG. 4  shows yet another female coupling member of the prior art which comprises a crown seal  70  having a dovetail configuration. In this design, there is no seal retainer or seal cartridge. Rather, the central axial bore of female member  20  has a section with a first, smaller inner diameter  114  and a section with a second, larger inner diameter  115  with an angled shoulder  110  between the two sections. Angled shoulder  110  engages a corresponding surface on the crown seal  70 . The opposite end of the crown seal  70  also has an angled surface that contacts angled surface  111  on retainer nut  112  which is in threaded engagement with the body of the female member  20 . As in the designs employing a seal retainer or a seal cartridge, circumferential O-rings  77  and  78  are used to provide a fluid-tight seal between the crown seal and the body of the coupling member. 
         [0030]    O-ring seals for high temperature and/or high pressure applications are typically made of specialty elastomers which are costly and not always readily available. In the case of couplings used chemical injection system applications, O-rings can be exposed to chemicals which would rapidly degrade ordinary elastomers. Accordingly, expensive, chemical-resistant materials must be used to fabricate the O-rings. Moreover, having one or more separate circumferential seals on the crown seal increases the part count of the coupling complicating both fabrication and repair processes. The present invention solves this problem. 
       BRIEF SUMMARY OF THE INVENTION 
       [0031]    A polymeric crown seal for a female hydraulic coupling member comprises integral sealing projections at the juncture of its outer circumference and dovetail shoulders obviating the need for separate O-ring seals. In a first embodiment, the projections have a generally circular cross section and project both radially and axially from the main body of the crown seal. In a second embodiment, the sealing projections comprise a ridge having a rounded distal end and extend only axially from the main body of the crown seal. 
         [0032]    Crown seals according to the present invention may be retrofitted in unmodified coupling members including those having seal retainers and those having seal cartridges. Alternatively, as disclosed herein, the receiving chamber of the female member, the seal retainer of a coupling member or the seal carrier of a coupling having a seal cartridge may be specially machined to engage the sealing projections on a crown seal according to the present invention. Likewise, the retainer nuts used to secure dovetail crown seals may have inner surfaces specially contoured to accommodate the corner sealing projections. 
         [0033]    Polymeric crown seals according to the present invention may be molded or machined to form. One particular preferred engineering plastic for this application is polyetheretherketone (PEEK). 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         [0034]      FIG. 1  is a cross-sectional view of a female hydraulic coupling member of the prior art having a crown seal in a seal retainer. 
           [0035]      FIG. 2  is a cross-sectional view of a crown seal of the prior art. 
           [0036]      FIG. 3  is a cross-sectional view of a female hydraulic coupling member of the prior art having a crown seal in a seal cartridge. 
           [0037]      FIG. 4  is a cross-sectional view of a female hydraulic coupling member of the prior art having a crown seal but no seal cartridge, seal retainer or metal C-seal. 
           [0038]      FIG. 5  is a cross-sectional view of a crown seal according to a first embodiment of the invention. 
           [0039]      FIG. 5A  is an enlargement of a portion of the crown seal shown in  FIG. 5 . 
           [0040]      FIG. 6  is a cross-sectional view of the crown seal illustrated in  FIG. 5  installed in a female hydraulic coupling having a seal retainer. 
           [0041]      FIG. 7  is a cross-sectional view of the crown seal illustrated in  FIG. 5  installed in a female hydraulic coupling having a seal cartridge. 
           [0042]      FIG. 8  is a cross-sectional view of the crown seal illustrated in  FIG. 5  installed in a female hydraulic coupling having a seal retaining nut. 
           [0043]      FIG. 9  is a cross-sectional view of the crown seal illustrated in  FIG. 5  installed in a female hydraulic coupling having a seal retainer specially adapted for engaging the sealing protrusions on the crown seal. 
           [0044]      FIG. 10A  is an enlarged cross-sectional view of a first portion of a crown seal and mating surface of a first type. 
           [0045]      FIG. 10B  is an enlarged cross-sectional view of a second portion of a crown seal and mating surface of a first type. 
           [0046]      FIG. 11A  is an enlarged cross-sectional view of a first portion of a crown seal and mating surface of a second type. 
           [0047]      FIG. 11B  is an enlarged cross-sectional view of a second portion of a crown seal and mating surface of a second type. 
           [0048]      FIG. 12  is a cross-sectional view of the crown seal illustrated in  FIG. 5  installed in a female hydraulic coupling having a seal cartridge specially adapted for engaging the sealing protrusions on the crown seal. 
           [0049]      FIG. 13  is a cross-sectional view of the crown seal illustrated in  FIG. 5  installed in a female hydraulic coupling having a body specially adapted for engaging the sealing protrusions on the crown seal. 
           [0050]      FIG. 14  is a cross-sectional view of a crown seal according to a second embodiment of the invention. 
           [0051]      FIG. 14A  is an enlargement of a portion of the crown seal shown in  FIG. 14 . 
           [0052]      FIG. 15  is a cross-sectional view of the crown seal illustrated in  FIG. 14  installed in a female hydraulic coupling having a seal retainer. 
           [0053]      FIG. 16  is a cross-sectional view of the crown seal illustrated in  FIG. 14  installed in a female hydraulic coupling having a seal retainer specially adapted to engage a sealing protrusion on the crown seal. 
           [0054]      FIG. 17  is a cross-sectional view of the crown seal illustrated in  FIG. 14  installed in a female hydraulic coupling having a seal cartridge. 
           [0055]      FIG. 18  is a cross-sectional view of the crown seal illustrated in  FIG. 14  installed in a female hydraulic coupling having a seal cartridge specially adapted to engage a sealing protrusion on the crown seal. 
           [0056]      FIG. 19  is a cross-sectional view of the crown seal illustrated in  FIG. 14  installed in the body of a female hydraulic coupling having a threaded retaining nut adapted to engage the sealing protrusion. 
           [0057]      FIG. 19A  is an enlargement of a first portion of the female hydraulic coupling shown in  FIG. 19 . 
           [0058]      FIG. 19B  is an enlargement of a second portion of the female hydraulic coupling shown in  FIG. 19B . 
           [0059]      FIG. 20  is a cross-sectional view of the crown seal illustrated in  FIG. 14  installed in a female hydraulic coupling whose body is specially adapted to engage a sealing protrusion on the crown seal. 
           [0060]      FIG. 20A  is an enlargement of a first portion of the female hydraulic coupling shown in  FIG. 20 . 
           [0061]      FIG. 20B  is an enlargement of a second portion of the female hydraulic coupling shown in  FIG. 20 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0062]    The invention may best be understood by reference to the accompanying drawing figures which illustrate two embodiments of the crown seal of the invention installed in both prior art female hydraulic coupling members and female coupling members according to the invention. 
         [0063]      FIG. 5  shows in cross section a crown seal  120  according to a first embodiment of the invention. Crown seal  120  is a generally cylindrical structure having a stepped outer diameter comprised of a first, outer section having smaller outside diameter  122  and a second, inner section having a larger outside diameter  124 . Inclined shoulder  126  forms the juncture of the two sections  122  and  124 . Crown seal  120  has a first, outer end  142  and a second, inner end  144  with a central, axial bore  146  which forms the receiving chamber for the male probe when seal  120  is installed in a female hydraulic coupling member. The terms “inner” and “outer” as used herein refer to the orientation of seal  120  as installed in a female coupling member. Outer end  142  is distal from the center (or interior) of the coupling while inner end  144  is proximal the center of the coupling. Angled surface  128  is adjacent inner end  144  of seal  120 . 
         [0064]    One or more sealing surfaces  134 ,  136  project into central axial bore  146  to seal against the outer, generally cylindrical surface of a male hydraulic probe (not shown) when inserted into the receiving chamber  146 . Although a single probe seal ( 134  or  136 ) may suffice for sealing purposes, it has been found that the provision of multiple probe seals helps to ensure proper alignment of the male member during insertion into receiving chamber  146 . 
         [0065]    Angled surfaces  126  and  128  form a dovetail interlock with corresponding surfaces in the female member (as described more fully, below). This interlock acts to resist the forces acting to urge the seal in a radial, inward direction (“seal implosion”) which may be encountered during withdrawal of the male member. As used herein, “angled surface” or “angled shoulder” mean an element that is not orthogonal to the central axis of the body—i.e., not “square.” Stated another way, an “angled surface” or “angled body” forms an angle other than 90° with the major axis of the body. 
         [0066]    Section  140  of crown seal  120  is an optional, bore liner extension. Within section  140 , the inner diameter of central, axial bore  146  may be progressively increased towards first end  142  from smaller internal diameter  148  to larger internal diameter  150 . Bore liner extension  140  lines the internal bore of the female hydraulic coupling member and prevents metal-to-metal contact (with possible consequential galling) between the male probe and the receiving chamber of the female member. The progressive reduction (in the inward direction) of the internal diameter in section  140  acts as a cam to direct a misaligned male probe into axial alignment as it is inserted into receiving chamber  146 . 
         [0067]    Body  138  of crown seal  120  may be fabricated from any suitable material. Polymers are particularly preferred for sealing effectiveness. Fabrication techniques include, but are not limited to, molding and machining. One, particularly preferred material for body  138  is polyetheretherketone (PEEK). PEEK is a thermoplastic with very favorable mechanical properties. The Young&#39;s modulus of PEEK is given as 3.6 GPa (522,000 psi) and its tensile strength 170 MPa (25,000 psi). PEEK is partially crystalline, and is highly unusual in exhibiting two glass transition temperatures at around 140° C. (284° F.) and around 275° C. (527° F.), depending on cure cycle and precise formulation. PEEK melts at around 350° C. (662° F.) and is highly resistant to thermal degradation. PEEK also exhibits good chemical resistance over a wide temperature range in many environments, including alkalis, aromatic hydrocarbons, alcohols, greases, oils and halogenated hydrocarbons. A crown seal according to the present invention may be machined from PEEK bar stock. It has been found that extruded PEEK bar stock is superior in this application to molded PEEK bar stock. 
         [0068]    Another particularly preferred material for the fabrication of body  138  is polyoxymethylene (POM), also commonly known by DuPont&#39;s brand name DELRIN. It is an engineering plastic, (a polymer) with the chemical formula —(—O—CH2—)n—. Often marketed and used as a metal substitute, Delrin is a lightweight, low-friction, and wear-resistant thermoplastic with good physical and processing properties capable of operating in temperatures in excess of 90 degrees Celsius (approx 200 degrees Fahrenheit). When supplied as extruded bar or sheet, DELRIN may be machined using traditional methods such as turning, milling, drilling, etc. 
         [0069]    Yet another preferred material for the fabrication of body  138  is polytetrafluoroethylene (PTFE), a synthetic fluoropolymer which finds numerous applications. PTFE is often referred to by the DuPont brand name TEFLON. 
         [0070]    Crown seal  120  includes one or more sealing projections  130 ,  132  on or near its outer circumference. In the embodiment illustrated in  FIG. 5 , sealing projections  130  and  132  have a generally circular cross section and project in both a radial and axial direction from the outer surface of body  138 . Sealing projection  130  is located at the juncture of angled shoulder  126  and outer diameter  124 .  FIG. 5A  is an enlarged detail of sealing projection  130  and the immediately adjacent portions of crown seal  120 . Sealing projection  132  is located at the juncture of angled surface  128  and outer diameter  124 . The size of sealing projection  130  and/or  132  may be selected according to the particular application. In one particular preferred embodiment wherein outer diameter  124  is approximately 0.895 inch, the diameter of the circular portions of sealing projections  130  and  132  is approximately 0.007 inch. In embodiments having a plurality of sealing projections, the size of each sealing projection may be the same as or different from other sealing projections. 
         [0071]      FIG. 6  shows a portion of a female hydraulic coupling member  160  comprising a crown seal  120  of the type illustrated in  FIG. 5 . A portion of poppet valve  170  and its associated valve actuator  168  are visible in the drawing figure. Coupling  160  includes seal retainer  166 , a generally sleeve-shaped member having a stepped inner diameter with an inner section of smaller I.D.  172  and an outer section of larger I.D.  174  and angled shoulder  176  joining the two sections. The inner face of seal retainer  166  has a ring-shaped groove for holding O-ring  182  which provides a fluid-tight seal between seal retainer  166  and the body of female member  160 . 
         [0072]    In the embodiment illustrated in  FIG. 6 , the inner face of seal retainer  166  also secures metal C-seal  180  on shoulder  178  of the central axial bore of female member  160 . C-seal  180  provides a pressure-energized seal between the female member and the probe of a male member inserted into receiving chamber  146 . 
         [0073]    Seal retainer  166  is held within the central axial bore of female member  160  by threaded retainer nut  184  which may comprise spanner holes  188  for engaging a tool to assist in seating and removing retainer nut  184 . The central axial bore of female member  160  may include internally threaded portion  164  proximate first end  162  for engaging the retainer nut  184 . Retainer nut  184  may comprise angled surface  186  sized and spaced to engage angled shoulder  126  of crown seal  120 . Likewise, seal retainer  166  may comprise angled shoulder  176  sized and spaced to engage angled surface  128  of crown seal  120 . In this way, the seal retainer  166  acting in concert with retainer nut  184  provides a dovetail type interlock with crown seal  120  to resist inward radial movement of seal  120 . 
         [0074]    Crown seal  120  is preferably sized such that sealing projections  130  and  132  are slightly compressed when retainer nut  184  is tightened against seal retainer  166  and seal retainer  166  is fully seated on shoulder  177 . In so doing, sealing projection  132  provides a fluid-tight seal between crown seal  120  and seal retainer  166  and sealing projection  130  provides a fluid-tight seal both between crown seal  120  and retainer nut  184  and between crown seal  120  and seal retainer  166 . 
         [0075]    It will be appreciated that seal retainer  166  and retainer nut  184  of  FIG. 6  are according to a design of the prior art (see, e.g. U.S. Pat. No. 4,900,071 to Robert E. Smith III). Thus, a crown seal  120  according to the present invention may be retrofitted to a female coupling member  160  by simply replacing the prior art crown seal—i.e. a crown seal having one or more circumferential O-ring seals or radial sealing projections. 
         [0076]      FIG. 7  shows a crown seal  120  of the type illustrated in  FIG. 5  in a female hydraulic coupling member having a seal cartridge comprised of seal carrier  190  and shell  198 . Seal carrier  190  is a generally sleeve-shaped member having both a stepped inner diameter and a stepped outer diameter. Angled shoulder  193  connects the inner portion having smaller I.D.  191  with the outer portion having larger I.D.  192 . Square shoulder  196  joins the inner portion having larger O.D.  194  with the outer portion having smaller O.D.  195 . Angled shoulder  193  is sized and spaced to engage angled surface  128  of crown seal  120 . 
         [0077]    Shell  198  is externally threaded in threaded portion  202  to engage the internally threaded portion  164  of the bore of the female coupling member. Spanner holes  204  may be provided to engage a tool for seating and removing the seal cartridge in the female coupling member. Shell  198  may have a slight interference fit with the portion of seal carrier  190  having smaller O.D.  195 . In this way, the entire seal cartridge including crown seal  120  may be removed for service from the female member by unthreading shell  198  from the bore of the female member. 
         [0078]    Shell  198  preferably comprises angled shoulder  200  sized and spaced to engage angled shoulder  126  on crown seal  120 . Together with shoulder  193 , angled shoulder  200  provides a dovetail-type interlock with surfaces  126  and  128  of crown seal  120  which resists implosion—i.e., inward radial movement—of crown seal  120  into receiving chamber  146  under conditions of low pressure in chamber  146  such as may be encountered during withdrawal of the male probe. 
         [0079]    Crown seal  120  is preferably sized such that sealing projections  130  and  132  are slightly compressed when shell  198  of the seal cartridge is tightened against seal carrier  190  and seal carrier  190  is fully seated on shoulder  177 . In so doing, sealing projection  132  provides a fluid-tight seal between crown seal  120  and seal carrier  190  and sealing projection  130  provides a fluid-tight seal both between crown seal  120  and shell  198  and between crown seal  120  and seal carrier  190 . 
         [0080]    It will be appreciated that the seal cartridge comprised of seal carrier  190  and shell  198  of  FIG. 7  is according to a design of the prior art (see, e.g. U.S. Pat. No. 7,021,677 to Robert E. Smith III). Thus, a crown seal  120  according to the present invention may be retrofitted to a female coupling member having a seal cartridge by simply replacing the prior art crown seal—i.e. a crown seal having one or more circumferential O-ring seals or radial sealing projections. 
         [0081]      FIG. 8  shows the use of a crown seal  120  according to the present invention in a female coupling member having neither a seal retainer nor a seal cartridge. Rather, the central axial bore of the female member has a first, inner section having smaller I.D.  206  and a second, outer section having larger I.D.  208  connected by angled shoulder  210 . Angled shoulder  210  engages angled surface  128  of crown seal  120 . 
         [0082]    Retainer nut  212  is externally threaded with threads  214  for engaging a threaded section of the central axial bore of the female member. Spanner holes  218  may be provided for engaging a tool for the insertion and removal of nut  212 . Retainer nut  212  comprises angled surface  216  sized and spaced to engage angled shoulder  126  of crown seal  120 . Angled shoulder  210  together with angled surface  216  provide a dovetail interlock with surfaces  126  and  128  of crown seal  120  which resists implosion—i.e., inward radial movement—of crown seal  120  into receiving chamber  146  under conditions of low pressure in chamber  146  such as may be encountered during withdrawal of the male probe. 
         [0083]    Crown seal  120  is preferably sized such that sealing projections  130  and  132  are slightly compressed when retainer nut  212  is fully seated on shoulder  213 . In so doing, sealing projection  132  provides a fluid-tight seal between crown seal  120  and the body of the female member and sealing projection  130  provides a fluid-tight seal both between crown seal  120  and retainer nut  212  and between crown seal  120  and the body of the female coupling member. 
         [0084]    It will be appreciated that the body of the female coupling member of  FIG. 8  and retaining nut  212  are according to a design of the prior art (see, e.g. U.S. Pat. No. 6,575,430 to Robert E. Smith III). Thus, a crown seal  120  according to the present invention may be retrofitted to such a female coupling member by simply replacing the prior art crown seal—i.e. a crown seal having one or more circumferential O-ring seals or radial sealing projections. 
         [0085]      FIG. 9  shows a female coupling member of the type illustrated in FIG.  6 —i.e., a female coupling member having a seal retainer. In this embodiment, seal retainer  166 ′ is modified to accommodate corner sealing projection  132  and/or corner sealing projection  130 . Retainer nut  184 ′ may also be modified to accommodate corner sealing projection  130  on crown seal  120 . 
         [0086]      FIG. 10A  is an enlarged detail of the contact area of retainer nut  184  and crown seal  120  as shown in  FIG. 9 . 
         [0087]      FIG. 10B  is an enlargement showing groove  220  between angled shoulder  176  (“A” in  FIG. 10B ) and the section of seal retainer  166 ′ having larger I.D.  174  (“B” in  FIG. 10B ). Groove  220  is preferably sized such that corner sealing projection  132  will fit at least partially into groove  220  and thereby provide greater sealing contact between seal retainer  166 ′ and crown seal  120 .  FIG. 11B  shows an alternative embodiment wherein groove  220  is undercut relative to section “B” to provide greater contact area to with sealing projection  132 . 
         [0088]      FIG. 11A  shows an alternative configuration for seal retainer  166 ′ wherein contour  222  is provided on the interior surface of seal retainer  166 ′ for accommodating corner sealing projection  130  on crown seal  120 . Either one or both of groove  220  and contour  222  may be provided on seal retainer  166 ′. The contour embodiment shown in  FIG. 11A  may conveniently be used with the groove embodiment shown in  FIG. 11B . 
         [0089]    As shown in  FIG. 9 , retainer nut  184 ′ may be provided with contour  224  for contacting corner sealing projection  130  on seal  120 . Groove  220  and/or contour  222  and/or contour  224  may increase the sealing effectiveness of corner sealing projections  130  and  132  of crown seal  120  by providing a larger area of contact between seal retainer  166 ′ and/or nut  184 ′ and the corner sealing projections  130  and  132 . 
         [0090]      FIG. 12  shows a female coupling member of the type illustrated in FIG.  7 —i.e., a female coupling member having a seal cartridge. In this embodiment, seal carrier  190 ′ is modified to accommodate corner sealing projection  132  and/or corner sealing projection  130 . Shell  198 ′ may also be modified to accommodate corner sealing projection  130  on crown seal  120 . 
         [0091]      FIG. 10B  is an enlargement showing groove  220  between angled shoulder  193  (“A” in  FIG. 10B ) and the section of seal carrier  190 ′ having larger I.D.  192  (“B” in  FIG. 10 ). Groove  220  is preferably sized such that corner sealing projection  132  will fit at least partially into groove  220  and thereby provide greater sealing contact between seal carrier  190 ′ and crown seal  120 . 
         [0092]      FIG. 11A  shows an alternative configuration for seal carrier  190 ′ wherein contour  222  is provided on the interior surface of seal carrier  190 ′ for accommodating corner sealing projection  130  on crown seal  120 . Either one or both of groove  220  and contour  222  may be provided on seal carrier  190 ′. 
         [0093]    As shown in  FIG. 12 , shell  198 ′ may be provided with contour  224  for contacting corner sealing projection  130  on seal  120 . Groove  220  and/or contour  222  and/or contour  224  may increase the sealing effectiveness of corner sealing projections  130  and  132  of crown seal  120  by providing a larger area of contact between seal carrier  190 ′ and/or shell  198 ′ and the corner sealing projections  130  and  132 . 
         [0094]      FIG. 13  shows a female coupling member of the type illustrated in FIG.  8 —i.e., a female coupling member having no seal cartridge, seal retainer or metal C-seal. In this embodiment, the body of the female member is modified to accommodate corner sealing projection  132  and/or corner sealing projection  130 . Retainer nut  212 ′ may also be modified to accommodate corner sealing projection  130  on crown seal  120 . 
         [0095]      FIG. 10B  is an enlargement showing groove  220  between angled shoulder  210  (“A” in  FIG. 10B ) and the portion of the central axial bore of the female member having larger I.D.  208  (“B” in  FIG. 10B ). Groove  220  is preferably sized such that corner sealing projection  132  will fit at least partially into groove  220  and thereby provide greater sealing contact between the body of female member  160  and crown seal  120 . 
         [0096]      FIG. 11  shows an alternative configuration for the female bore wherein contour  222  is also provided on the interior surface of the central axial bore for accommodating corner sealing projection  130  on crown seal  120 . Either one or both of groove  220  and contour  222  may be provided on the interior surface of the central axial bore. 
         [0097]    As shown in  FIG. 13 , retainer nut  212 ′ may be provided with contour  224  for contacting corner sealing projection  130  on seal  120 . Groove  220  and/or contour  222  and/or contour  224  may increase the sealing effectiveness of corner sealing projections  130  and  132  of crown seal  120  by providing a larger area of contact between the body of female member  160  and/or retainer nut  212 ′ and the corner sealing projections  130  and  132 . 
         [0098]    A crown seal according to a second embodiment of the invention is shown in  FIG. 14 . This embodiment has sealing projections on the exterior surface of the seal which project only in the axial direction—i.e., the outside diameter of seal is not affected by the practice of the invention. This feature is of particular benefit in certain applications wherein a seal according to the invention is retrofitted to an existing coupling member. 
         [0099]    Crown seal  320  is a generally cylindrical structure having a stepped outer diameter comprised of a first, outer section having smaller outside diameter  322  and a second, inner section having a larger outside diameter  324 . Inclined shoulder  326  forms the juncture of the two sections  322  and  324 . Crown seal  320  has a first, outer end  342  and a second, inner end  344  with a central, axial bore  346  which forms the receiving chamber for the male probe when seal  320  is installed in a female hydraulic coupling member. The terms “inner” and “outer” as used herein refer to the orientation of seal  320  as installed in a female coupling member. Outer end  342  is distal from the center (or interior) of the coupling while inner end  344  is proximal the center of the coupling. Angled surface  328  is adjacent inner end  344  of seal  320 . 
         [0100]    One or more sealing surfaces  334 ,  336  project into central axial bore  346  to seal against the outer, generally cylindrical surface of a male hydraulic probe (not shown) inserted into the receiving chamber  346 . Although a single probe seal ( 134  or  336 ) may suffice for sealing purposes, it has been found that the provision of multiple probe seals helps to ensure proper alignment of the male member during insertion into receiving chamber  346 . 
         [0101]    Angled surfaces  326  and  328  form a dovetail interlock with corresponding surfaces in the female member (as described more fully, below). This interlock acts to resist the forces acting to urge the seal in a radial, inward direction (“seal implosion”) which may be encountered during withdrawal of the male member. 
         [0102]    Section  340  of crown seal  320  is an optional, bore liner extension. Within section  340 , the inner diameter of central, axial bore  346  may be progressively increased towards first end  342  from smaller internal diameter  348  to larger internal diameter  350 . Bore liner extension  340  lines the internal bore of the female hydraulic coupling member and prevents metal-to-metal contact (with possible consequential galling) between the male probe and the receiving chamber of the female member. The progressive reduction (in the inward direction) of the internal diameter in section  340  acts as a cam to direct a misaligned male probe into axial alignment as it is inserted into receiving chamber  346 . 
         [0103]    Body  338  of crown seal  320  may be fabricated from any suitable material. PEEK and POM polymers are particularly preferred, as described above in connection with the embodiment shown in  FIG. 5 . 
         [0104]    Crown seal  320  includes one or more axial sealing projections  330 ,  332  on or near its outer circumference. In the embodiment illustrated in  FIG. 5 , sealing projections  330  and  332  have a distal portion with a generally semicircular circular cross section and project in an axial direction from the outer surface of body  338 . Sealing projection  330  is located at the juncture of angled shoulder  326  and outer diameter  324 .  FIG. 14A  is an enlarged, detail view showing sealing projection  330  and the immediately adjacent portions of crown seal  320 . Sealing projection  332  is located at the juncture of angled surface  328  and outer diameter  324 . The size of sealing projection  330  and/or  332  may be selected according to the particular application. In one particular preferred embodiment wherein outer diameter  324  is approximately 0.895 inch, the diameter of the semicircular portions of sealing projections  330  and  332  is approximately 0.007 inch. In embodiments having a plurality of axial sealing projections, the size of each sealing projection may be the same as or different from other axial sealing projections. 
         [0105]      FIG. 15  shows a portion of a female hydraulic coupling member  160  comprising a crown seal  320  of the type illustrated in  FIG. 14 . A portion of poppet valve  170  and its associated valve actuator  168  are visible in the drawing figure. Coupling  160  includes seal retainer  166 , a generally sleeve-shaped member having a stepped inner diameter with an inner section of smaller I.D.  172  and an outer section of larger I.D.  174  and angled shoulder  176  joining the two sections. The inner face of seal retainer  166  has a ring-shaped groove for holding O-ring  182  which provides a fluid-tight seal between seal retainer  166  and the body of female member  160 . 
         [0106]    In the embodiment illustrated in  FIG. 15 , the inner face of seal retainer  166  also secures metal C-seal  180  on shoulder  178  of the central axial bore of female member  160 . C-seal  180  provides a pressure-energized seal between the female member and the probe of a male member inserted into receiving chamber  346 . 
         [0107]    Seal retainer  166  is held within the central axial bore of female member  160  by threaded retainer nut  360  which may comprise spanner holes  188  for engaging a tool to assist in seating and removing retainer nut  360 . The central axial bore of female member  160  may include internally threaded portion  164  proximate first end  162  for engaging the retainer nut  360 . Retainer nut  360  may comprise contoured angled surface  362  sized and spaced to engage both angled shoulder  326  of crown seal  320  and axial sealing projection  330 . Likewise, seal retainer  166  may comprise angled shoulder  176  sized and spaced to engage angled surface  328  of crown seal  320 . In this way, the seal retainer  166  acting in concert with retainer nut  360  provides a dovetail type interlock with crown seal  320  to resist inward radial movement of seal  320 . 
         [0108]    Crown seal  320  is preferably sized such that axial sealing projections  330  and  332  are slightly compressed when retainer nut  360  is tightened against seal retainer  166  and seal retainer  166  is fully seated on shoulder  177 . In so doing, sealing projection  332  provides a fluid-tight seal between crown seal  320  and seal retainer  166  and sealing projection  330  provides a fluid-tight seal both between crown seal  320  and retainer nut  360  and between crown seal  320  and seal retainer  166 . 
         [0109]    It will be appreciated that seal retainer  166  of  FIG. 15  is according to a design of the prior art (see, e.g. U.S. Pat. No. 5,052,439 to Robert E. Smith III). Thus, a crown seal  320  according to the present invention may be retrofitted to a female coupling member  160  by simply replacing the prior art crown seal—i.e. a crown seal having one or more circumferential O-ring seals or radial sealing projections. Optionally, retainer nut  360  having contoured angled shoulder  362  may also be retrofitted to the coupling member to increase the sealing effectiveness of axial sealing projection  330 . 
         [0110]      FIG. 16  shows a female coupling member of the type illustrated in FIG.  15 —i.e., a female coupling member having a seal retainer. In this embodiment, seal retainer  410  is modified to accommodate axial sealing projection  332 . The modification comprises groove  412  at the outer edge of angled shoulder  176 ′ of seal retainer  410 . Groove  412  is preferably sized and spaced to accommodate axial sealing projection  332  on crown seal  320  thereby increasing its sealing effectiveness by providing a greater area of contact as compared to the embodiment illustrated in  FIG. 15 . 
         [0111]      FIG. 17  shows a crown seal  320  of the type illustrated in  FIG. 14  in a female hydraulic coupling member having a seal cartridge comprised of seal carrier  190  and shell  370 . Seal carrier  190  is a generally sleeve-shaped member having both a stepped inner diameter and a stepped outer diameter. Angled shoulder  193  connects the inner portion having smaller I.D.  191  with the outer portion having larger I.D.  192 . Square shoulder  196  joins the inner portion having larger O.D.  194  with the outer portion having smaller O.D.  195 . Angled shoulder  193  is sized and spaced to engage angled surface  328  of crown seal  320 . 
         [0112]    Shell  370  is externally threaded in threaded portion  202  to engage the internally threaded portion  164  of the bore of the female coupling member. Spanner holes  204  may be provided to engage a tool for seating and removing the seal cartridge in the female coupling member. Shell  370  may have a slight interference fit with the portion of seal carrier  190  having smaller O.D.  195 . In this way, the entire seal cartridge including crown seal  320  may be removed for service from the female member by unthreading shell  370  from the bore of the female member. 
         [0113]    Shell  370  preferably comprises contoured angled shoulder  372  sized and spaced to engage angled shoulder  326  and axial sealing projection  330  on crown seal  320 . Together with shoulder  193 , contoured angled shoulder  372  provides a dovetail-type interlock with surfaces  326  and  328  of crown seal  320  which resists implosion—i.e., inward radial movement—of crown seal  320  into receiving chamber  346  under conditions of low pressure in chamber  346  such as may be encountered during withdrawal of the male probe. 
         [0114]    Crown seal  320  is preferably sized such that axial sealing projections  330  and  332  are slightly compressed when shell  198  of the seal cartridge is tightened against seal carrier  190  and seal carrier  190  is fully seated on shoulder  177 . In so doing, sealing projection  332  provides a fluid-tight seal between crown seal  320  and seal carrier  190  and sealing projection  330  provides a fluid-tight seal both between crown seal  320  and shell  198  and between crown seal  320  and seal carrier  190 . 
         [0115]    It will be appreciated that the seal cartridge comprised of seal carrier  190  and shell  198  of  FIG. 17  is according to a design of the prior art (see, e.g. U.S. Pat. No. 7,163,190 to Robert E. Smith III). Thus, a crown seal  320  according to the present invention may be retrofitted to a female coupling member having a seal cartridge by simply replacing the prior art crown seal—i.e. a crown seal having one or more circumferential O-ring seals or radial sealing projections. 
         [0116]      FIG. 18  shows a female coupling member of the type illustrated in FIG.  17 —i.e., a female coupling member having a seal cartridge. In this embodiment, seal carrier  400  is modified to accommodate axial sealing projection  332 . Groove  402  at the outer portion of angled shoulder  193 ′ is sized and spaced to fit axial sealing projection  332  on seal  320 . Shell  370  may also be modified to accommodate axial sealing projection  330  on crown seal  320  by the provision of contoured angled shoulder  372  which may be sized and contoured to fit both angled shoulder  326  and axial sealing projection  330  of seal  320 . 
         [0117]    Groove  402  and/or contoured surface  372  may increase the sealing effectiveness of axial sealing projections  330  and  332  of crown seal  320  by providing a larger area of contact between seal carrier  400  and/or shell  370  and the axial sealing projections  330  and  332 . 
         [0118]      FIG. 19  shows the use of a crown seal  320  according to the present invention in a female coupling member having neither a seal retainer nor a seal cartridge. Rather, the central axial bore of the female member has a first, inner section having smaller I.D.  206  and a second, outer section having larger I.D.  208  connected by angled shoulder  210 . Angled shoulder  210  engages angled surface  328  of crown seal  320 . 
         [0119]    Retainer nut  380  is externally threaded with threads  214 ′ for engaging a threaded section of the central axial bore of the female member. Spanner holes  218 ′ may be provided for engaging a tool for the insertion and removal of nut  380 . Retainer nut  380  comprises contoured angled surface  382  sized and spaced to engage angled shoulder  326  and axial sealing projection  330  of crown seal  320 . Angled shoulder  210  together with angled surface  326  provide a dovetail interlock with surfaces  326  and  328  of crown seal  320  which resists implosion—i.e., inward radial movement—of crown seal  320  into receiving chamber  346  under conditions of low pressure in chamber  346  such as may be encountered during withdrawal of the male probe. 
         [0120]    Crown seal  320  is preferably sized such that sealing projections  330  and  332  are slightly compressed when retainer nut  380  is fully seated on shoulder  213 . In so doing, sealing projection  332  provides a fluid-tight seal between crown seal  320  and the body of the female member and sealing projection  330  provides a fluid-tight seal both between crown seal  320  and retainer nut  380  and between crown seal  320  and the body of the female coupling member.  FIG. 19A  is an enlargement of the contact region between sealing projection  330  and retainer nut  380 .  FIG. 19B  is an enlargement of the contact region between sealing projection  332  and angled surface  210 . 
         [0121]    It will be appreciated that the body of the female coupling member of  FIG. 19  is according to a design of the prior art (see, e.g. U.S. Pat. No. 6,575,430 to Robert E. Smith III). Thus, a crown seal  320  according to the present invention may be retrofitted to such a female coupling member by simply replacing the prior art crown seal—i.e. a crown seal having one or more circumferential O-ring seals or radial sealing projections—and, optionally, the retainer nut. 
         [0122]      FIG. 20  shows a female coupling member of the type illustrated in FIG.  8 —i.e., a female coupling member having no seal cartridge, seal retainer or metal C-seal. In this embodiment, the body of the female member is modified to accommodate axial sealing projection  332 . As shown in detail in  FIG. 20B , groove  394  at the outer limit of angled shoulder  210 ′ is sized and spaced to fit axial sealing projection  332 . 
         [0123]    Retainer nut  390  may also be modified to accommodate axial sealing projection  330  on crown seal  320 . As shown in  FIG. 20A , retainer nut  390  may be provided with contoured angled surface  392  for contacting axial sealing projection  330  and angled shoulder  326  on seal  320 . As shown in detail in  FIG. 20B , Groove  394  and/or contoured angled surface  392  may increase the sealing effectiveness of axial sealing projections  330  and  332  of crown seal  320  by providing a larger area of contact between the body of female member  160 ′ and/or retainer nut  390  and the axial sealing projections  330  and  332 . 
         [0124]    Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.