Swaged-type flexible hose coupling

An improved hose coupling assembly, particularly adapted for a motor vehicle air conditioning system, comprising:

• a flexible hose including a portion constituting a liner of deformable gas impermeable thermoplastic material;
• a tubular fitting having an end portion received within one end of said liner;
• said end portion including a plurality of axially spaced annular ribs having an outer diameter substantially equal to that of said fitting, said liner being in slight interference fit with said ribs upon initial insertion of the liner onto said end portion, said ribs including a pair of sealing ribs, each said sealing rib being of substantially equal axial width;
• an annular sealing groove disposed between said sealing ribs and having a base wall;
• said sealing ribs including opposing sidewalls defining the width of said sealing groove and having an axial width at least equal to the width of said sealing groove;
• an annular resilient sealing member in the shape of an O-ring fitted within said sealing groove and engaging the inner surface of said liner upon initial insertion of the liner onto said end portion in compression to a value ranging from about 10% to no more than about 35% of the unstressed O-ring, said O-ring filling at least 85% of the volume of said sealing groove upon initial insertion of the liner onto said end portion;
• a sleeve member surrounding the outer surface of said hose and fixed to said fitting, said sleeve member being radially inwardly deformed at a plurality of axially spaced substantially annular locations to provide radially inwardly directed annular locking ribs which exert a clamping force on said hose to thereby secure said hose on said fitting;
• said sleeve locking ribs being disposed axially outwardly of said pair of sealing ribs;
• said plurality of ribs further including at least a first pair of tubular fitting locking ribs, each being disposed on opposite sides of said sealing groove and axially spaced from a respective sealing rib to provide a locking groove and thereby providing a liner retaining means for locking said liner in place axially relative to said tubular fitting over an operating temperature range of up to at least about 300.degree. F. and for sealing said liner relative to said tubular fitting over said operating temperature range to thereby preclude the passage of fluids and gases from said coupling;
• said resilient sealing member being centrally axially located between an adjacent pair of said sleeve locking ribs;
• said pair of sealing ribs providing means for dissipating said clamping force whereby the compression of said resilient seal member will be substantially unaffected, and
• each said sleeve locking rib being generally located radially opposite a respective locking groove whereby the maximum clamping force is applied direction upon said liner at the locking grooves and a minimum clamping force is directed upon said resilient sealing member.