Abstract:
An air conditioner system fitting is disclosed including a first seal portion with a metal material adapted to provide a primary seal, and a second seal portion attached to a free edge of the first seal portion and adapted to provide a secondary seal, wherein the fitting militates against leakage during operation of the air conditioning system.

Description:
FIELD OF THE INVENTION 
     The invention relates to a fitting for a vehicle air condition system and more particularly to a fitting for coupling tubing segments, the fitting including a seal structure having a first seal portion and a second seal portion 
     BACKGROUND OF THE INVENTION 
     In assembly line manufacturing of vehicles, it is desirable that line fittings in an air conditioning system can be secured using a power nut driver rather than using a torque wrench. For this reason, peanut or block type fittings are often used. 
     Various refrigerants such as R12, R134a, and CO 2  have been used in the air conditioning system for the vehicle. However, environmental concerns exist. As a result, legislation has been passed by various governmental agencies of the United States and the European Union, for example, requiring that the air conditioning system operate with substantially no refrigerant leaks. 
     Seal structures having multiple seals have been used to militate against leaks from the fittings used in the air conditioning system. These prior art seal structures have included rubber O-rings and elastomeric seals, for example. However, over time, such seals can degrade. Damage to the seal structure can also occur due to improper installation or handling. 
     It would be desirable to produce a fitting including a seal structure for use in an air conditioning system which minimizes a leaking of a refrigerant from the air conditioning system. 
     SUMMARY OF THE INVENTION 
     Concordant and congruous with the present invention, a fitting including a seal structure for use in an air conditioning system which minimizes a leaking of a refrigerant from the air conditioning system, has surprisingly been discovered. 
     In one embodiment, the seal structure comprises a first seal portion forming an annular ring including a free edge and formed from a metal material; and a second seal portion extending outwardly from the free edge of said first seal portion. 
     In another embodiment, the seal structure comprises a first seal portion forming an annular ring including a free edge and formed from a soft metal material; and a second seal portion extending outwardly from the free edge of said first seal portion and formed from an elastomer. 
     In yet another embodiment, a block fitting comprises a male block portion including a first aperture adapted to receive a tube end therein, said male block portion including an annular shoulder; a female block portion including a first aperture adapted to receive a tube end therein, said female block portion including an annular collar surrounding the first aperture of said female block portion and adapted to abut the annular shoulder formed by said male block portion, the first aperture of said male block portion and the first aperture of said female block portion being substantially concentrically aligned; a first seal portion having a free edge, said first seal portion surrounding the first aperture of said male block portion and the first aperture of said female block portion, wherein said first seal portion provides a primary seal between said male block portion and said female block portion; a second seal portion disposed on the free edge of said first seal portion, wherein the second seal provides a secondary seal between said male block portion and said female block portion; and a fastener adapted to engage said male block portion and said female block portion to sealingly engage said male block portion and said female block portion. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which: 
         FIG. 1  is a top plan view of a seal structure according to an embodiment of the invention; 
         FIG. 2  is a cross-sectional view of the seal structure of  FIG. 1  taken along line  2 - 2 ; 
         FIG. 3  is a cross-sectional view of a fitting including the seal structure illustrated in  FIGS. 1 and 2 ; 
         FIG. 4  is a cross-sectional view of a fitting according to another embodiment of the invention including the seal structure illustrated in  FIGS. 1 and 2 ; 
         FIG. 5  is a front elevational view of a seal structure according to another embodiment of the invention; 
         FIG. 6  is a top plan view of the seal structure illustrated in  FIG. 6 ; 
         FIG. 7  is a cross-sectional view of the seal structure of  FIG. 6  taken along line  7 - 7 ; and 
         FIG. 8  is a cross-sectional view of a fitting including the seal structure illustrated in  FIGS. 5 ,  6 , and  7 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following detailed description and appended drawings describe and illustrate various exemplary embodiments of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner. It is understood that materials other than those described can be used without departing from the scope and spirit of the invention. 
       FIG. 1  shows a seal structure  10  according to an embodiment of the invention. Although the embodiment shown and described is used for a block type fitting for an air conditioning system, it is understood that the seal structure  10  can be used with other fitting types as desired. 
     The seal structure  10  includes a first seal portion  12  and a second seal portion  14 . The first seal portion  12  is a substantially flat annular ring. As illustrated in  FIG. 2 , the ring has a first surface  16  and a second surface  18 . An outer free edge  20  of the first seal portion  12  has a chamfer formed thereon. It is understood that the outer free edge  20  can be any shape such as substantially square or rounded, for example. It is further understood that the outer free edge  20  can be continuous or scalloped to facilitate retention of the second seal portion  14  on the first seal portion  12 . The cross-sectional shape of the first seal portion  12  is substantially rectangular, although other cross-sectional shapes can be used as desired such as triangular, oval, and other radial curves, for example. It is also understood that channels or grooves can be formed in the first surface  16  and the second surface  18  of the first seal portion  12 . In the embodiment shown, the first seal portion  12  is produced from a tin-coated copper. However, it is understood that other conventional materials can be used as desired such as laminated tetrafluoroethylene, rubber-coated aluminum, PEEK, Vespel, pewter, babbit, bronze, nickel, polyamide, aluminum, and other metal coated or rubber-coated metals, for example. 
     The second seal portion  14  extends radially outwardly from the outer free edge  20  of the first seal portion  12 . An annular channel  22  is formed in a radial inner portion  24  of the second seal portion  14 . The annular channel  22  is adapted to receive the outer free edge  20  of the first seal portion  12 . The second seal portion  14  is fastened to the first seal portion  12  by any conventional fastening means such as vulcanizing, heat welding, press fitting, an adhesive, or a mechanical means of attachment, for example. A radial outer portion  26  extends radially outwardly from the radial inner portion  24 . The second seal portion  14  is substantially diamond shaped in cross-section, wherein opposing sides of the second seal portion  14  are substantially V-shaped in cross-section. In the embodiment shown, the second seal portion  14  is produced from an elastomer. It is understood that the second seal portion  14  may be produced from any conventional material such as an ethylene propylene diene monomer (EPDM) and hydrogenated acrylonitrile butadiene rubber (HNBR), for example. 
     In  FIG. 3 , the seal structure  10  is shown disposed in a block fitting  28 . The block fitting  28  includes a male block portion  30  and a female block portion  32 . The male block portion  30  includes a first aperture  34  having a generally circular cross-section, and is adapted to receive a tube or conduit  36 . It is desirable, although not critical, to have a clearance fit between the tube  36  and the bore  37  for brazing. The tube  36  can be further joined to the male block portion  30  by any conventional method such as by brazing or welding, for example. It is understood that the male block portion  30  may form a trap  39  for a brazing material (not shown) to militate against the migration of the brazing material towards the annular surfaces  43 ,  45 . The male block portion  30  includes a second aperture  38  adapted to receive a fastener (not shown). 
     An annular shoulder  40  is formed on a second end of the male block portion  30  and includes an axially extending lip  41  formed at a first end thereof. The lip  41  surrounds an annular surface  43 . An annular channel  42  is formed in the annular surface  43 . It is understood that a protuberance (not shown) can be formed on the annular surface  43  in place of or in addition to the channel  42 . In the embodiment shown, the channel  42  is substantially v-shaped in cross-section, and is adapted to sealingly receive one of the opposing V-shaped sides of the second sealing member  14  therein. However, it is understood that a protuberance (not shown) can be formed on the annular surface  43  in place of or in addition to the channel  42 . In the embodiment shown, the channel  42  is substantially v-shaped in cross-section, and is adapted to sealingly receive one of the opposing V-shaped sides of the second sealing member  14  therein. However, it is understood that channels  42  having other shapes can be used as desired. A sealing bead  48  is formed on the annular surface  43  of the male block portion  30  radially inward of the channel  42 . Although the sealing bead  43  of the male block portion  30  radially inward of the channel  42 . Although the sealing bead  48  shown has a v-shaped cross-section, other shapes can be used such as a curved radius, rectangular, or other shape, for example. Only one sealing bead  48  is shown, however, a plurality of sealing beads  48  can be used if desired, resulting in concentric rings. 
     The female block portion  32  includes a first aperture  50  having a generally circular cross-section, and is adapted to receive a tube or conduit  52 . The tube  52  is joined to the female block portion  32  by any conventional method such as by brazing or welding, for example. It is understood that the female block portion  32  may also form the trap  39  for a brazing material (not shown) to militate against the migration of the brazing material towards the annular surfaces  43 ,  45 . The female block portion  32  includes a second aperture  54  formed therein adapted to receive the fastener. 
     An annular collar  44  is formed on a second end of the female block portion  32  and surrounds the first aperture  50 . An annular surface  45  is formed between the annular collar  44  and the first aperture  50 . The annular surface  45  includes an annular channel  46  formed therein. It is understood that a protuberance (not shown) can be formed on the annular surface  45  in place of the channel  46  or in addition to the channel  46 . It is understood that channels  46  having cross-sectional shapes other than that shown can be used. A sealing bead  49  is formed on the annular surface  45  radially inward of the channel  46 . The sealing bead  49  may have any cross-sectional shape other than that shown, as desired. A plurality of sealing beads  49  can also be used if desired, resulting in concentric rings. 
     To assemble the block fitting illustrated in  FIG. 3 , the tube  36  is inserted in the first aperture  34  of the male block portion  30  and secured. The tube  52  is inserted in the first aperture  50  of the female block portion  32  and secured. The seal structure  10  is disposed within the annular lip  41  such that a portion of the second seal portion  14  is disposed on the annular surface  43  of the male block portion  30  and a remainder of the second seal portion  14  is disposed in the channel  42 . The seal structure  10  abuts the annular surface  45  of the female block portion  32  such that a portion of the second seal portion  14  is disposed on the annular surface  45  and a remainder of the second seal portion  14  is disposed in the channels  46 . The sealing beads  48 ,  49  abut the first seal portion  12  of the seal structure  10 . The male block portion  30  and the female block portion  32  are moved adjacent one another. The fastener is inserted through the second apertures  38 ,  54  and tightened to sealingly engage the male block portion  30  and the female block portion  32 . The sealing beads  48 ,  49  deform the first seal portion  12  of the seal structure  10  to form a primary seal. The second seal portion  14  of the seal structure  10  creates a secondary seal with the walls of the annular surfaces  43 ,  45 . Once assembled, the male block portion  30  and the female block portion  32  cooperate with the seal structure  10  to form a fluid tight seal, and militate against leakage of a fluid (liquid or gas) from the tubes  36 ,  52 . If an amount of the fluid flowing through the tubes  36 ,  52  leaks past the primary seal formed by the first seal portion  12  and the sealing beads  48 ,  49 , the second seal portion  14  militates against the leakage of the fluid from the block fitting  28  to the atmosphere. The second seal portion  14  also serves as an environmental seal keeping harmful contaminants away from the first seal portion  10 . The second seal portion  14  is also a retainer to keep the seal structure  10  in the male block portion  30  during shipping and handling prior to assembly of the block fitting  28 . 
       FIG. 4  shows a block fitting  60  for use with the seal structure  10  according to another embodiment of the invention. The block fitting  60  includes a male block portion  62  and a female block portion  64 . The male block portion  62  includes a first aperture  66  having a generally circular cross-section, and is adapted to receive a tube or conduit  68 . It is desirable, although not critical, to have a press fit between the tube  68  and the wall forming the first aperture  66 . Splines  69  formed on the wall forming the first aperture  66  can also be used to accomplish the desired interference fit. The tube  68  can be further joined to the male block portion  62  by any conventional method such as by brazing or welding, for example. The male block portion  62  includes a second aperture  76  formed therein adapted to receive a fastener (not shown). 
     An annular shoulder  78  is formed on the male block portion  62 , and includes an axially extending lip  79  formed at a first end thereof. The lip  79  surrounds an annular surface  81 . The annular surface  81  is adapted to receive a first end  70  of the tube  68 . An annular channel  72  is formed in the first end  70 . It is understood that a protuberance (not shown) can be formed on the first end  70  in place of or in addition to the channel  72 . In the embodiment shown, the channel  72  is substantially v-shaped in cross-section. However, it is understood that channels  72  having other shapes can be used as desired. A sealing bead  74  is formed on the first end  70  of the tube  68  radially inward of the channel  72 . Although the sealing bead  74  shown has a v-shaped cross-section, other shapes can be used such as a curved radius, a rectangular, or other shape for example. A plurality of sealing beads  74  can also be used if desired, resulting in concentric rings. 
     The female block portion  64  includes a first aperture  88  having a generally circular cross-section. In the embodiment shown, the first aperture  88  is adapted to receive a tube or conduit  80 . It is desirable, although not critical, to have a press fit between the tube  80  and the wall forming the first aperture  88 . Splines  69  formed on the wall forming the first aperture  88  can also be used to accomplish the desired interference fit. Also, the tube  80  may be joined to the female block portion  64  by any conventional method such as by brazing or welding, for example. The female block portion  64  includes a second aperture  90  adapted to receive the fastener. An annular collar  86  is formed on a second end of the female block portion  64  to surround the first aperture  88 , and includes an annular surface  87 . The annular surface  87  is adapted to receive the first end  82  of the tube  80 . An annular channel  84  is formed in the first end  82 . It is understood that a protuberance (not shown) can be formed on the first end  82  in place of or in addition to the channel  84 . In the embodiment shown, the channel  84  is substantially v-shaped in cross-section. However, it is understood that channels  84  having other shapes can be used as desired. A sealing bead  75  is formed on the first end  82  of the tube  80  radially inward of the channel  84 . Although the sealing bead  75  shown has a v-shaped cross-section, other shapes can be used such as a curved radius, a rectangular, or other shape for example. A plurality of sealing beads  75  can also be used if desired, resulting in concentric rings. 
     To assemble the embodiment of the invention illustrated in  FIG. 4 , the tube  68  is inserted in the first aperture  66  of the male block portion  62  with the first end  70  disposed adjacent and radially inward of the annular shoulder  78 . The tube  80  is inserted in the first aperture  88  of the female block portion  64  with the first end  82  disposed adjacent and radially inward of the annular collar  86 . The seal structure  10  is disposed between the first end  70  of the tube  68  and the first end  82  of the tube  80 . A portion of the second seal portion  14  is received on a surface  73  of the tube  68 . A remainder of the second seal portion  14  is received on a surface  85  of the tube  80 . The sealing beads  74 ,  75  abut the first seal portion  12  of the seal structure  10 . The male block portion  62  and the female block portion  64  are moved adjacent one another. The fastener is inserted through the second apertures  76 ,  90  and tightened to sealingly engage the male block portion  62  and the female block portion  64 . The sealing beads  74 ,  75  deform the first seal portion  12  of the seal structure  10  to form a primary seal. The second seal portion  14  of the seal structure  10  forms a secondary seal with the surfaces  73 ,  85 . Once assembled, the first end  70  of the tube  68  and the first end  82  of the tube  80  cooperate with the seal structure  10  to form a fluid tight seal, and militate against leakage of a fluid (liquid or gas) from the tubes  68 ,  80 . If an amount of the fluid flowing through the tubes  68 ,  80  leaks past the primary seal formed by the first seal portion  12  and the sealing beads  74 ,  75 , the second seal portion  14  militates against leakage of the fluid from the tubes  68 ,  80  to the atmosphere. The second seal portion  14  also serves as an environmental seal keeping harmful contaminants away from the first seal portion  10 . The second seal portion  14  is also a retainer to keep the seal structure  10  in the male block portion  62  during shipping and handling prior to assembly of the block fitting  60 . 
       FIGS. 5 through 7  show a seal structure  10 ′ according to another embodiment of the invention. The seal structure  10 ′ includes a first seal portion  12 ′ and a second seal portion  14 ′. As shown in  FIG. 6 , the first seal portion  12 ′ forms an annular ring. As illustrated in  FIG. 7 , the first seal portion  12 ′ has a first surface  16 ′, a second surface  18 ′, and a flange  19 ′ extending axially from an outer peripheral edge of the first surface  16 ′. The flange  19 ′ ends at an outer free edge  20 ′. It is understood that the outer free edge  20 ′ can be any shape such as beveled or substantially square or rounded, for example. It is further understood that the outer free edge  20 ′ can be continuous or scalloped to facilitate retention of the second seal portion  14 ′ on the flange  19 ′. 
     The cross-sectional shape of the first seal portion  12 ′ is substantially L-shaped. It is understood that other cross-sectional shapes can be used as desired. It is also understood that channels or grooves can be formed in the first surface  16 ′, the second surface  18 ′, and the flange  19 ′ of the first seal portion  12 ′. In the embodiment shown, the first seal portion  12 ′ is produced from a tin-coated copper. However, it is understood that other conventional materials can be used as desired such as laminated tetrafluoroethylene, rubber-coated aluminum, PEEK, Vespel, pewter, babbit, bronze, nickel, polyamide, aluminum, and other metal coated or rubber-coated metals, for example. 
     The second seal portion  14 ′ extends axially outwardly from an outer free edge  20 ′ of the flange  19 ′ of the first seal portion  12 ′. An annular channel  22 ′ is formed in a first end  24 ′ of the second seal portion  14 ′. The annular channel  22 ′ is adapted to receive the outer free edge  20 ′ of the flange  19 ′ of the first seal portion  12 ′. The second seal portion  14 ′ is fastened to the first seal portion  12 ′ by any conventional fastening means such as vulcanizing, heat welding, press fitting, an adhesive, or a mechanical means of attachment, for example. A second end  26 ′ is spaced from the first end  24 ′. In the embodiment shown, the second seal portion  14 ′ is produced from an elastomer. It is understood that the second seal portion  14 ′ may be produced from any conventional material such as an ethylene propylene diene monomer (EPDM) or a hydrogenated acrylonitrile butadiene rubber (HNBR), for example. 
     In  FIG. 8 , the seal structure  10 ′ is shown disposed in a block fitting  28 ′. The block fitting  28 ′ includes a male block portion  30 ′ and a female block portion  32 ′. The male block portion  30 ′ includes a first aperture  34 ′ having a generally circular cross-section, and is adapted to receive a conduit or tube  36 ′. It is desirable, although not critical, to have a clearance fit between the tube  36 ′ and the bore  37 ′ for brazing. Splines (not shown) formed on the wall forming the first aperture  34 ′ can be used to accomplish the desired interference fit. The tube  36 ′ can further be joined to the male block portion  30 ′ by any conventional method such as by brazing or welding, for example. The male block portion  30 ′ includes a second aperture  38 ′ formed therein adapted to receive a fastener (not shown). 
     An annular shoulder  40 ′ is formed on a second end of the male block portion  30 ′ and includes an axially extending lip  41 ′ formed at a first end thereof. An annular channel  42 ′ is formed in an outer wall of the lip  41 ′. It is understood that a protuberance (not shown) can be formed on the outer wall of the lip  41 ′ in place of or in addition to the channel  42 ′. In the embodiment shown, the channel  42 ′ is substantially rectangular in cross-section. However, it is understood that channels  42 ′ having other shapes can be used as desired. A sealing bead  48 ′ is formed on the lip  41 ′ of the male block portion  30 ′. Although the sealing bead  48 ′ shown has a v-shaped cross-section, other shapes can be used such as a curved radius, a rectangular, or other shape, for example. Only one sealing bead  48 ′ is shown, however, more sealing beads  48 ′ can be used if desired, resulting in concentric rings. 
     The female block portion  32 ′ includes a first aperture  50 ′ having a generally circular cross-section, and is adapted to receive a conduit or tube  52 ′. The tube  52 ′ is joined to the female block portion  32 ′ by any conventional method such as by brazing or welding, for example. It is desirable, although not critical, to have a clearance fit between the tube  52 ′ and the bore  37 ′ for brazing. The female block portion  32 ′ includes a second aperture  54 ′ formed therein adapted to receive the fastener. 
     An annular collar  44 ′ is formed on a second end of the female block portion  32 ′ and surrounds the first aperture  50 ′. The annular collar  44 ′ forms an annular channel  46 ′ therein. An annular surface  45 ′ is formed between the annular collar  44 ′ and the first aperture  50 ′. It is understood that a protuberance (not shown) can be formed on the inner wall of the annular collar  44 ′ in place of the channel  46 ′ or in addition to the channel  46 ′. It is understood that the channel  46 ′ may have any cross-sectional shape other than that shown. A sealing bead  49 ′ is formed on the annular surface  45 ′ radially inward of the annular collar  44 ′. The sealing bead  49 ′ may have any cross-sectional shape other than that shown, as desired. Additional sealing beads  49 ′ can also be used if desired, resulting in concentric rings. 
     To assemble the block fitting illustrated in  FIG. 8 , the tube  36 ′ is inserted in the first aperture  34 ′ of the male block portion  30 ′. The tube  52 ′ is inserted in the first aperture  50 ′ of the female block portion  32 ′. The seal structure  10 ′ is disposed over the annular shoulder  40 ′ of the male block portion  30 ′ and is positioned to allow the flange  19 ′ of the seal structure  10 ′ to abut the outer wall of the annular shoulder  40 ′ of the male block portion  30 ′ and the inner wall of the annular collar  44 ′. The male block portion  30 ′ and the female block portion  32 ′ are moved adjacent one another. A portion of the second seal portion  14 ′ is received in the channel  46 ′ of the female block portion  32 ′. A remaining portion of the second seal portion  14 ′ is received in the channel  42 ′ of the male block portion  30 ′. The flange  19 ′ abuts the lip  41 ′ of the male block portion  30 ′. The sealing beads  48 ′,  49 ′ abut the first seal portion  12 ′ of the seal structure. The fastener is inserted through the second apertures  38 ′,  54 ′ and tightened to sealingly engage the male block portion  30 ′ and the female block portion  32 ′. The sealing beads  48 ′,  49 ′ deform the first seal portion  12 ′ of the seal structure  10 ′ to form a primary seal. The second seal portion  14 ′ of the seal structure  10 ′ creates a secondary seal with the walls of the channels  42 ′,  46 ′. Once assembled, the male block portion  30 ′ and the female block portion  32 ′ cooperate with the seal structure  10 ′ to form a fluid tight seal, and militate against leakage of a fluid (liquid or gas) from the tubes  36 ′,  52 ′. If an amount of the fluid flowing through the tubes  36 ′,  52 ′ leaks past the primary seal formed by the first seal portion  12 ′ and the sealing beads  48 ′,  49 ′, the second seal portion  14 ′ militates against the leakage of the fluid from the block fitting  28 ′ to the atmosphere. The second seal portion  14 ′ also serves as an environmental seal keeping harmful contaminants away from the first seal portion  10 ′. The second seal portion  14 ′ is also a retainer to keep the seal structure  10 ′ in the male block portion  30 ′ during shipping and handling prior to assembly of the block fitting  28 ′. 
     From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions.