Double metal seal fitting

A thermal expansion valve for an air conditioning system comprising:

• a plurality of tubes, each of the tubes having a flanged tube end, the flanged tube end including a first sealing surface with a first sealing bead formed thereon;
• a plurality of collars, each of the collars having an outer wall with an opening formed therein, the opening receiving one of the tubes, the flanged tube end abutting the wall of one of the collars, each of the collar having an axially extending annular wall surrounding the opening and the flanged tube end;
• a hollow main body including a plurality of ports, each of the ports receiving one of the collars and the tube end of one of the tubes, the ports each having a base with an annular groove formed therein, the annular groove receiving the axially extending wall of one of the collars, each of the ports having a second sealing surface with a second sealing bead formed thereon and disposed radially inward from the annular groove, the second sealing surface surrounding an aperture formed in the base of the first port;
• a plurality of seal structures, each of the seal structures disposed radially inward from the axially extending wall of one of the collars and between the flanged tube end of the one of the tubes and the main body, each seal structure including a first seal portion produced from a plastically deformable metal or plastic material and having a free edge, and a second seal portion produced from an elastomer disposed on the free edge of the first seal portion;
• a pair of end plates having the main body disposed therebetween, each of the end plates receiving at least one of the tubes and abutting the wall of the of one of the collars opposite the flanged tube end;
• and
• a plurality of fasteners engaging the end plates and the main body, the fasteners causing the first sealing beads of the tubes and the second sealing beads of the ports to plastically deform the first seal portions of the seal structures and provide primary seals between the tubes and the ports, and the fasteners causing the first sealing surface of the tubes and the second sealing surface of the first port to cooperate with the second seal portions of the seal structures and provide secondary seals between the tubes and the ports, wherein the primary seals and the secondary seals militate against a leakage of refrigerant from the thermal expansion valve.

A thermal expansion valve for an air conditioning system comprising:

• a first tube having a flanged tube end, the flanged tube end including a first sealing surface with a first sealing bead formed thereon, wherein the first tube is a suction line to a compressor;
• a second tube having a flanged tube end, the flanged tube end including a first sealing surface with a first sealing bead formed thereon, wherein the second tube is an outlet line from an evaporator;
• a third tube having a flanged tube end, the flanged tube end including a first sealing surface with a first sealing bead formed thereon, wherein the third tube is a refrigerant inlet line;
• a fourth tube having a flanged tube end, the flanged tube end including a first sealing surface with a first sealing bead formed thereon, wherein the fourth tube is an inlet line to the evaporator;
• a first collar having an outer wall with an opening formed therein, the opening receiving the first tube, the flanged tube end abutting the wall of the first collar, the first collar having an axially extending annular wall surrounding the opening and the flanged tube end;
• a second collar having an outer wall with an opening formed therein, the opening receiving the second tube, the flanged tube end abutting the wall of the second collar, the second collar having an axially extending annular wall surrounding the opening and the flanged tube end;
• a third collar having an outer wall with an opening formed therein, the opening receiving the third tube, the flanged tube end abutting the wall of the third collar, the third collar having an axially extending annular wall surrounding the opening and the flanged tube end;
• a fourth collar having an outer wall with an opening formed therein, the opening receiving the fourth tube, the flanged tube end abutting the wall of the fourth collar, the fourth collar having an axially extending annular wall surrounding the opening and the flanged tube end;
• a hollow main body including a first port receiving the first collar and the tube end of the first tube, a second port receiving the second collar and the tube end of the second tube, a third port receiving the third collar and the tube end of the third tube, and a fourth port receiving the fourth collar and the tube end of the fourth tube, each of the first port, the second port, the third port and fourth port having a base with an annular groove disposed therein, the annular groove of the first port cooperating with the axially extending wall of the first collar, the annular groove of the second port cooperating with the axially extending wall of the second collar, the annular groove of the third port cooperating with the axially extending wall of the third collar, and the annular groove of the fourth port cooperating with the axially extending wall of the fourth collar, each of the first port, the second port, the third port, and the fourth port having a second sealing surface with a second sealing bead formed thereon and disposed radially inward from the annular groove, the second sealing surface surrounding an aperture formed in the base of each of the first port, the second port, the third port, and the fourth port;
• a first seal structure disposed radially inward from the axially extending wall of the first collar and between the flanged tube end of the first tube and the main body, the first seal structure including a first seal portion produced from a plastically deformable metal or plastic material and having a free edge, and a second seal portion produced from an elastomer disposed on the free edge of the first seal portion;
• a second seal structure disposed radially inward from the axially extending wall of the second collar and between the flanged tube end of the second tube and the main body, the second seal structure including a first seal portion produced from a plastically deformable metal or plastic material and having a free edge, and a second seal portion produced from an elastomer disposed on the free edge of the first seal portion;
• a third seal structure disposed radially inward from the axially extending wall of the third collar and between the flanged tube end of the third tube and the main body, the third seal structure including a first seal portion produced from a plastically deformable metal or plastic material and having a free edge, and a second seal portion produced from an elastomer disposed on the free edge of the first seal portion;
• a fourth seal structure disposed radially inward from the axially extending wall of the fourth collar and between the flanged tube end of the fourth tube and the main body, the fourth seal structure including a first seal portion produced from a plastically deformable metal or plastic material and having a free edge, and a second seal portion produced from an elastomer disposed on the free edge of the first seal portion;
• a first end plate receiving the first tube and the third tube, and abutting the wall of the first collar opposite the flanged tube end of the first tube and the wall of the third collar opposite the flanged tube end of the third tube;
• and
• a second end plate receiving the second tube and the fourth tube, and abutting the wall of the second collar opposite the flanged tube end of the second tube and the wall of the fourth collar opposite the flanged tube end of the fourth tube;
• a first fastener engaging the first end plate and the main body, the first fastener causing the first sealing bead of the first tube and the second sealing bead of the first port to plastically deform the first seal portion of the first seal structure and provide a primary seal between the first tube and the first port, and the first fastener causing the first sealing surface of the first tube and the second sealing surface of the first port to cooperate with the second seal portion of the first seal structure and provide a secondary seal between the first tube and the first port, and the first fastener causing the first sealing bead of the third tube and the second sealing bead of the third port to plastically deform the first seal portion of the third seal structure and provide a primary seal between the third tube and the third port, and the first fastener causing the first sealing surface of the third tube and the second sealing surface of the third port to cooperate with the second seal portion of the third seal structure and provide a secondary seal between the third tube and the third port;
• and
• a second fastener engaging the second end plate and the main body, the second fastener causing the first sealing bead of the second tube and the second sealing bead of the second port to plastically deform the first seal portion of the second seal structure and provide a primary seal between the second tube and the second port, and the second fastener causing the first sealing surface of the second tube and the second sealing surface of the second port to cooperate with the second seal portion of the second seal structure and provide a secondary seal between the second tube and the second port, and the second fastener causing the first sealing bead of the fourth tube and the second sealing bead of the fourth port to plastically deform the first seal portion of the fourth seal structure and provide a primary seal between the fourth tube and the fourth port, and the second fastener causing the first sealing surface of the fourth tube and the second sealing surface of the fourth port to cooperate with the second seal portion of the fourth seal structure and provide a secondary seal between the fourth tube and the fourth port,
• wherein the primary seals and the secondary seals militate against a leakage of refrigerant from the thermal expansion valve.