Air conditioner access and service fittings

• US 6,273,397 B1
• Filed: 12/27/1999
• Issued: 08/14/2001
• Est. Priority Date: 12/27/1999
• Status: Expired due to Term

• Current Assignee: Schrader-Bridgeport International Incorporated (Pacific Industrial Company Limited)
• Original Assignee: Schrader-Bridgeport International Incorporated (Pacific Industrial Company Limited)
• Inventors: Schultz, Jeffrey A., Gilbert, Major H.
• Primary Examiner(s): Shaver, Kevin
• Assistant Examiner(s): BONDERER, DAVID A
• Application Number:
  US09/472,260
• Time in Patent Office: 596 Days
• Field of Search: 251/149.6, 251/149.9, 251/216, 251/218, 251/220, 251/221, 251/225, 251/291, 137/614.18
• US Class Current: 251/149.6
• CPC Class Codes: F25B 2309/061 with cycle highest pressure above the supercritical pressure
• CPC Class Codes: F25B 2345/006 characterised by charging or discharging valves
• CPC Class Codes: F25B 41/40 Fluid line arrangements
• CPC Class Codes: Y10T 137/88038 One valve head carries other valve head

Abstract

An air conditioner access fitting includes a valve body having a threaded bore and an annular valve seat extending around the bore. A twist-to-open valve is disposed in the bore and threadedly engaged with the valve body. The valve includes a valve element configured to form a metal-to-metal seal with the valve seat. A valve core is disposed in a second bore formed in the twist-to-open valve, and the valve core operates selectively to open and close a flow path extending through the second bore. The valve body further includes a quick connect shoulder disposed around the bore. An associated service fitting includes a quick release mechanism, a wrench for rotating the twist-to-open valve, and a valve core depressor for opening the valve core.

Claims

1. An air conditioner access fitting comprising:

a valve body comprising a threaded bore and an annular valve seat extending around the bore, said valve body configured and said valve seat positioned such that all fluid that passes through the bore crosses the valve seat;

a twist-to-open valve disposed in the bore and threadedly engaged with the valve body, said valve comprising a valve element configured to form a metal-to-metal seal with the valve seat, said metal-to-metal seal stopping substantially all fluid flow through the bore and the flow path when the twist-to-open valve is closed;

said valve body further comprising a quick-connect shoulder disposed around the bore.

2. The invention of claim 1 wherein the twist-to-open valve comprises a second bore in fluid communication with the valve seat, and wherein the access fitting further comprises:

a valve core disposed in the second bore and operative selectively to open and close a flow path extending through the second bore.

3. The invention of claim 1 wherein the twist-to-open valve comprises an end portion opposite the valve element, said end portion extending out of the valve body and comprising a plurality of wrench flats.

4. The invention of claim 1 further comprising:

a locking element disposed between the valve body and the twist-to-open valve to restrain the twist-to-open valve from movement out of the bore.

5. The invention of claim 4 wherein the locking element comprises a split ring secured to the twist-to-open valve.

6. The invention of claim 5 wherein the valve body comprises:

an inwardly-facing chamfer adjacent an open end of the bore, said chamfer configured to compress the split ring at assembly; and

an annular recess positioned to receive the split ring, said recess positioned to allow the split ring to move along the bore to accommodate movement of the twist-to-open valve as a result of rotation of the twist-to-open valve relative to the valve body, said recess terminating in a shoulder positioned to prevent the split ring from moving beyond the shoulder toward the chamfer.

7. The invention of claim 1 wherein the valve body comprises a body portion configured for connection to an air conditioner system, wherein the twist-to-open valve comprises a set of external threads that threadedly engage the bore, and wherein the valve seat is disposed between the body portion and the external threads.

13. The invention of claim 1 or 15 wherein the twist-to-open valve comprises a second bore in fluid communication with the valve seat such that a flow path exists through the valve seat into the second bore when the valve element is spaced from the valve seat.

14. The invention of claim 13 further comprising:

a valve core disposed in the second bore and operative to open and close the flow path.

15. The invention of claim 14 wherein the flow path is configured with the second bore and the first valve seat in series such that substantially all fluid moving through the access fitting along the flow path passes through the valve seat and across the core.

8. An air conditioner access fitting comprising:

a valve body comprising a threaded bore and an annular valve seat extending around the bore, said valve body configured and said valve seat positioned such that all fluid that passes through the bore crosses the valve seat;

a twist-to-open valve disposed in the bore and threadedly engaged with the valve body, said valve comprising a valve element configured to form a metal-to-metal seal with the valve seat, said metal-to-metal seal stopping substantially all fluid flow through the bore and the flow path when the twist-to-open valve is closed;

said valve body further comprising an external connection feature disposed around the bore;

wherein the valve body comprises an external sealing surface.

9. The invention of claim 8 wherein the valve body comprises a set of internal threads, and wherein the sealing surface and the valve seat are disposed on opposite sides of the set of internal threads.

10. The invention of claim 8 wherein the sealing surface and the valve seat are disposed on opposite sides of the external connection feature.

11. The invention of claim 8 wherein the valve body is formed in one piece.

12. The invention of claim 8 wherein the external connection feature comprises a quick-connect shoulder.

16. An air conditioner access fitting comprising:

a valve body comprising a threaded bore that forms a refrigerant introduction/removal flow path; and

an annular valve seat extending around the bore;

a twist-to-open valve disposed in the bore and threadedly engaged with the valve body, said valve comprising a valve element configured to form a metal-to-metal seal with the valve seat;

said valve body further comprising a quick-connect shoulder disposed around the bore;

a locking element disposed between the valve body and the twist-to-open valve to restrain the twist-to-open valve from movement out of the bore;

wherein the locking element comprises a split ring secured to the twist-to-open valve;

an inwardly-facing chamfer adjacent an open end of the bore, said chamfer configured to compress the split ring at assembly; and

an annular recess positioned to receive the split ring, said recess positioned to allow the split ring to move along the bore to accommodate movement of the twist-to-open valve as a result of rotation of the twist-to-open valve relative to the valve body, said recess terminating in a shoulder positioned to prevent the split ring from moving beyond the shoulder toward the chamfer.