CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U .S. Patent Application Serial No.

14/100,287, tiled December 9, 2013, which Is incorporated by reference herein.

BACKGROUND OF THE INVENTION

Field of the Invention

This application relates to a refrigeration valve and, more specifically, to a method of making a bail valve for an air conditioner/refrigerator having a ball valve member disposed within a hermetically sealed chamber.

Background Information

Refrigeration and air conditioners typically use an isolatio valve having a stem-type shut-off mechanism and a flowpath with a ninety degree angle. Such valves are typically cast as a single, unitary body with the valve stem being the only major separate component. Such a unitary body is, essentially; leak proof Le. gases cannot escape through the body, and, as such, leaks typically only occur about the stem. While such valves are adequate, there is a pressure drop that occurs due to the angled flowpath. A valve having a generally straight flowpath would not have such a pressure drop and, therefore, would reduce the amount of time needed to charge refrigerant or pull a vacuum in a system.

Ball valves have a generally straight flowpath. Bail valves have a housing that defines a passage and a ball valve member disposed therein. The ball valve member is a metal sphere, e.g. steel, brass or other metals, having a central passage. Seals, typically made f om PoiyTetraFliioroEthylene (Teflon® by DuPont) or similar materials, are disposed between the ball valve and the chamber in which it is disposed. The ball rotates between a first, closed position, wherein the ball valve member central passage is not aligned with, nor in fluid communication with, the housing passage and a second position, wherein the ball valve member central passage is aligned with, and in fluid communication with, the housing passage. A handle assembly has an external handle and a stem. The stem has first, inner end coupled to the bail, valve member and a second, outer end that is coupled to the handle, allowing for rotation of the ball valve member. There are seals disposed about the stem as well.

A ball valve housing for an air conditiofter refrigeratot typically includes a copper inlet tube, a brass fitting assembly, and a copper outlet tube. The brass fitting assembly is structured to support and sealingl engage the ball valve member seals and the stem seals. The brass fitting has two portions, a body and a bonnet. These portions define a ball chamber, in which the ball valve member is disposed. The body and bonnet are joined together by & threaded coupling. It is noted that, as the body and bonnet are threaded together, seals disposed between the ball and the brass fitting assembly are compressed into a sealing engagement with the bail valve member. The brass fitting assembly also includes an inlet port and an outlet port. The copper inlet tube is brazed to the inlet port. The copper outlet tube is brazed to the outlet port. The distal ends of the copper inlet tube and the copper outlet tube are structure to be coupled to the fluid system for an air conditioaer/refiigerator. In this configuration, the brass fitting assembly has a potential leak path at the interface between the body and the bonnet- It would be advantageous to have a ball valve with a straight flow path that is hermetically sealed. It is known that welding/brazing creates a hermetic seal. Such a method of construc tion for a bail valve, how ever, would require the v alve member to be in situ during the welding/brazing. The valv member seals would be damaged by the temperatures associated with such welding/brazing.

There is, therefore, a need for a ball valve having a hermetic seal between the body and bonnet. SUMMARY OF THE INVENTION

The disclosed and claimed concept provides for a service ball val ve assembly and a method of making the ball valve assembly having a hermetic seal between the body and bonnet. As used herein, a "service" valve includes an external connection whereby a serv ice line may be attached thereto. The ball valve assembly is sized for use with household refrigerators and air conditioners. That is, the ball valve assembly, in an exemplary embodiment, has a passage diameter of about 0.318 in. diameter. The ball valve assembly is, in an exemplary embodiment, made from brass. It is noted that, for large, commercial and/or industrial refrigeration and air conditioning units, it is known to use large ball valves which may be sealed by welds. As used herei», a "large" ball valve has a passage that is greater than 0.49999 inch in diameter. "Large" ball valves are used as system valves, i.e. valves that are integral to the cooling circuit and do not have a external connection. Such large ball valves are manufactured by different methods than retail sized ref igeration valve assemblies and used in very different environments. Therefore, as used herein., "refrigeration ball valve" means a relatively small valve assembly sized for use on refrigerators/air conditioners and does not include lame ball valves used for commercial and or industrial sized refrigeration and air conditioning units.

The method of making the ball valve includes the steps of providing refrigeration ball va!ve fitting components including a body, a bonnet, and a ball valve member and a seal, wherein the fitting body defines a ball valve chamber and the bail valve member seals are disposed between the fitting body ball valve chamber and the ball valve member; then, positioning the bail valve member and ball valve member seals in the fitting bodv ball valve chamber, coupling the fitt m body and the fitting bonnet at a circular interface, and, coupling the fitting body and the fitting bonnet by a metal coupling.

it is noted that the method is accomplished by limiting the seals exposure to heat. As such, the dimensions of the elements, e.g. the distance between the metal coupling and the seals, as well as the time it takes to create the metal coupling is important.

BRIEF DESCRIPTION OF THE DRAWINGS

A full u nderstandi n g of the inv ention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which:

Figure 1 is a side view of a refrigeration valve.

Figure 2 is a cross- sectional view of a refrigeration valve.

Figure 3 is a flow chart of the method steps.

Figure 4 is a schematic side view of a heat absorbing support.

Figure 5 is a schematic side view of a support with a cooling fluid apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Directional phrases used herein, such as, for example, clockwise,

counterclockwise, left, right, top, bottom, upwards, downwards and derivatives thereof, relate to the orientation of the elements shown in the drawings and are not limiting upon the claims unless expressly recited therein.

As used herein, the singular form of "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

As used herein, the statement that two or more parts or components are "coupled" shall mean that the parts are joined or operate together either directly or indirectly, /.£?., through one or more intermediate parts or components, so long as a link occurs. As used herein, ^' " ^' directly coupled" means that two elements are directly in contact wit eac other. As used herein, "fixedly coupled" or "fixed" means that two components are coupled so as to move as one while maintaining a constant orientation relative to each other. Accordingly, when two elements are coupled, all portions of those elements are coupled. A description, however, of a specific portion of a first element being coupled to a second element, e.g., an axle first end being coupled to a first wheel means that the specific portion of the first element is disposed closer to the second element than the other portions thereof. Further, an object resting o anothe object held in place only by gravity is not "coupled" to the lower object unless the upper object is otherwise maintained substantially in place. That is, for example, a book on a table is not coupled thereto, but a book glued to a table is coupled thereto.

As used herein, the statement that two or more parts or components "engage" one another shall mean that the elements exert a force or bias against one another either directly or through one or more intermediate elements or components,

As used herein, the word "unitary" means a component is created as a single piece or unit. That is, a component that includes pieces that are created separately and which are then coupled together as a unit is not a ''unitary" component or body.

As used herein, the term "number" shall mean one or an integer greater than one (i.e., a plurality).

As used herein, a "coupling assembly" includes two or more couplings or coupling components. The components of a coupling or coupling assembly are generally not part of the same element or other component. As such, the components of a "coupling assembly" ma not be described at the same time in the following description. As used herein, a "coupling" or "coupling co ponent(s)" is one or -more components) of a coupling assembly. That is, a coupling assembly includes at least two components that are structured to be coupled together, it is understood that the components of a coupling assembly are compatible with each other. For example, in a coupling assembly., if one coupling component is a snap socket, the other coupling component is a snap plug, or, if one coupling component, is a bolt, then the other coupling component is a nut.

As used herein, "associated" means that the elements are pan of th same assembly and/or operate together, or, act upon/with each other in some manner. For example, an automobile has four tires and four huh caps. While ail the elements are coupled as part of the automobile, it is understood that each hubcap is "associated" with a specific tire.

As used herein, "correspond" indicates that two structural components are sized and shaped to be similar to each other and may he coupled with a minimum amount of friction. Thus, an opening which "corresponds" to a member is sized slightly larger than the member so thai the member may pass through the opening with a minimum amount of friction. This definition is modified if the two

components are said to fit "snugly" together or "smiggly correspond." In that situation, the difference between the size of the components is even smaller whereby the amount of friction increases. If the element defining the opening and/or the component inserted into the opening are made from a deformah!e or compressible material, the opening may even be slightly smaller than the component bein inserted into the opening. This definition is further modified if the two components are said to "substantially correspond." "Substantially correspond" means that the size of the opening is very close to the size of the element inserted therein; that is, not so close as to cause substantial friction, as with a snu« fit, but with more contact and friction than a "corresponding fit," i.e., a "slightly larger" fit. Further, as used herein, "loosely correspond" means thai a slot or opening is sized to be larger than a element disposed therein. This means that the increased size of the slot or opening is intentional and is more than a manufacturinu tolerance. Further, with reaard to a surfac formed by two or more elements, a "corresponding" shape means that surface features, e.g. curvature., are similar.

As used herein, "structured to [verb]" means that the identified element or assembly has a structure that is shaped, sized, disposed, coupled and/or configured to perform the identified verb. For example, a member that is "structured to move' ⁵ is movably coupled to another element and includes elements that cause the member to move or the member is othenvise configured to move in response to other elements or assemblies,

As used herein, "at" means on or near.

As used herein, a "metal coupling" is a coupling created by a high temperature process such as brazing or welding. It is noted that, as used herein, a coupling created at a lower temperature, such as by soldering, is not a "metal coupling."

As shown in Figure 1 , a. refrigeration valve 10 includes a fitting 12 and a valve assembly 14, The fitting 12 defines an elongated passage 13 (Fig. 2) having an inlet 16 and an outlet 18. The passage 13 has a cross-sectional area of between about 0.049 and 0,076 square inch, or about 0.0625 square inch, in an exemplary embodiment, the passage 13 is generally circular and has a diameter of between about 0.25 inch and 0.35 inch or about 0.312 inch. The fitting 12 also defines a ball valve chamber 20 disposed between the inlet 16 and the outlet i 8. The fitting 12 is. in an exemplary embodiment, made from brass, copper or stainless steel. The fitting Ϊ 2 includes a bod 22, a bonnet 24, and a handle assembly 26. As shown in Figure 2, the fitting body 22 includes the inlet 1 and the ball valve chamber 20 as well as a stem passage 28 and an outlet collar 29. More specifically, the fitting body 22 has a proximal end 30 and a distal end 32. The fitting body distal end 32 is the inlet 16, As described below, the bonnet 24 is coupled to the fitting body outlet coilar 29 and is the outlet 18, In an exemplary embodiment, the inlet 16 and the outlet 18 are each elongated and substantially disposed about the same axis. The ball valve chamber 20 is disposed between the fitting body distal end 32 and the fitting body proximal end 30, The fitting body proximal end 30, i.e. outlet collar 29, in an exemplary embodiment, has a generally circular shape as well as inner threads 34. The stem passage 28 extends from outside the fitting body 22 into the ball valve chamber 20. The stem passage 28 extends generally perpendicular to the longitudinal axis of the passage 13.

in an exemplary embodiment, the ball valve chamber 20 has a sidewall thickness of between about 0,05 and 0,75 inch, or about 0.63 inch. live ball val ve chamber 20 has an inner diameter of between about 0.4 and 0.6 inch, or about 0.515 inch. The outlet collar 29 has a length of between about 0, 15 inch and 0.35 inch, or about 0.245 inch. In this configuration, and as described below, the bonnet 24 is coupled to the outlet, collar 29 at a circular interface 31. Further, when the ball valve member 52, discussed below, is disposed in. the bail, valve chamber 20, the circular interface 31 is spaced between about 0.34 inch and 0.54 inch, or about 0.44 inch, from the outer surface of the ball seal 58, discussed below, ad acent the circular interface 31.

'Die bonnet 24 is an elongated, tubular member having a proximal end 40 and a distal end 42. The bonnet proximal end 40 has a generally circular shape as well as outer threads 44. The bonnet proximal end 40 and the fitting body proximal end 30 are structured to be coupled together by the threaded portions 34, 4. The interface of the bonnet proximal end 40 and the fitting body proximal end 30 closest to the ball valve chamber 20 defines the circular interface 31 , The bonnet distal end 42 is a circular fitting selected from the group consisting of: hose barbs, flare by flare, flare by swivel flare, tube to tube, and flare by non-swivel flare.

The valve assembly 14 is, in an exemplary embodiment, a ball valve assembly 50 having a ball valve member 52 and a seal assembly 54. The ball val ve member 52 is a substantially smooth sphere having a central passage 56. The ball valve member 52 is sized to correspond to the inner diameter of the ball val ve chamber 20. hi one embodiment, the ball valve member central passage 56 is, in an exemplary embodiment, sized to correspond to the size of the passage 13, as discussed above. That is, the ball valve member central passage 56 has a cross-sectional area of between about 0,049 and 0.076 square inch, or about 0,625 square inch, in an exemplary embodiment, the passage 13 is generall circular and has a diameter of between about 0.25 inch and 0.35 inch or about 0.312 inch. In another embodiment, the bail valve member centra! passage 56 has a diameter of between about 0.23 inch and 0,33 inch, or about 0.28 inch. In this configuration, the interface between the surface of the ball valve member central passage 56 and the ball seal(s) 58, discussed below, is greater than in the prior embodiment. The ball valve member 52 may also include a slot 57 cut into the external surface. In a exemplary embodiment, the slot 57 extends, generally, parallel to the ball valve member central passage 56.

The seal assembly 54 includes a number of ball seals 58 and a number of stem seals 59. in an exemplary embodiment there are at least two ball seals 58, a first ball seal 58' and a second ball seal 58", and at least one stem seal 59. The ball seals 58 are disposed between the bad valve member 52 and the fitting 12. As used herein, the "outer surface" of the ball seals 58 is the surface disposed away from the ball val ve member 52. Each ball seal 58 is a torus, In an exemplary embodiment, the ball seals 58 are made ixom one of PTFE, also known as Teflon® by DuPont, TFM™ by Dyneon™ a 3 Company with 25% carbon filler, or TFM™ Virgin b Dyneon™ a 3M Company. When each ball seal 58 is installed, the central opening is aligned with the fitting passage 13, It is noted thai, during assembly, the first ball seal 58 is initially installed within the hall valve chamber 20. Next; the ball valve member 52 is installed, thereby trapping the first ball seal 58 between the ball valve member 52 and the fitting body 22. The second bail seal 58 is then installed within the ball valve chamber 20. The fitting body 22 and the fitting bonnet 24 are then coupled by the threaded proximal ends 30, 40. As the fitting bonnet 24 is drawn toward the fitting body 22, the ball seals 58 are compressed between the fitting 12 and the ball valve member 52. That is, when the fitting body 22 and fitting bonnet 24 are threadably coupled, said bail valve assembly 50 is sea!ingly compressed within the fitting 12.

The handle assembly 26 includes a generally circular stem 60 and a handle member 62. The stem 60 has a first, inner end 64 and a second, outer end 66. The stem first end 64 is generally flat and sized to fit within the ball valve member slot 57. The stem second end 66 is structured to be fixed to the handle member 62, The at least one stem seal 59 is sized to extend about the stem 60.

When assembled, the ball valve member 52 is disposed in the ball valve chamber 20 as described above. Further, the ball valve member slot 57 is generally aligned with the fitting body stem passage 28. Thus, the stem 60 may be disposed within the stem passage 28 with the stem first end 64 disposed within the ball valve member slot 57. The at least one stem seal 59 is sealingly compressed betwee the stem 60 and the stem passage 28. It is noted that, as shown in the figures, there are three stem seals 59. The handle member 62 is fixed to the stem second end 66.

In this configuration, the valve assembly 14 is structured to move between a first, closed position, wherein a fluid is restricted from flowing from the inlet 16 to the outlet 18, and a second, open position, wherein a fluid is substantially free to flow from the inlet 16 to the outlet 18, it is further noted that, in this configuration, the passage 13, that is the passage extending through the fitting inlet 16, the fitting outlet 18 and the valve assembly 1 in the open position, defines a generally straight passage 13 for a fluid, in this configuration, the fluid passing through the

refrigeration valve 10 does not suffer .from a pressure drop as is common in valves having an angled fiowpath. The refrigeration val e 10 further includes an additional hermetic seal 70. That is, the fitting body 22 and fitting bonnet 24 are hermetically sealed by a metal coupling. The hermetic seal 70 is disposed at the exposed circular interface 31 of the fitting body 22 and the fitting bonnet 24 threaded proximal ends 30, 40. In this configuration, it is essentially impossible for fluid within the refrigeration valve 1.0 to escape at the fitting body 22/fiifi.ng bonnet 24 interface. Thus, for fluid to escape the refri eration valve 10, the fluid would have to bypass at least one bail seal 58 and, in the embodiment shown, three stem seals 59.

In addition to the assembly steps noted above, the method of making a hermetically sealed refrigeration valve 10 includes the following steps. Initially, there is the step of providing 100 the refrigeration ball valve fitting 12 components including a body 22, a bonnet 24, a ball valve member 52, and a number of ball seals 58, wherein the fitting body 22 defines a bail valve chamber 20, and wherein the ball valve member 52 corresponds to the fitting body ball valve chamber 20. The method further includes, positioning 101 a first ball seal 58' in the fitting body ball valve chamber 20, positioning .102 the ball valve member 52 in the fitting body ball valve chamber 20, positioning .103 a second ball seal in the fitting body ball valve chamber 20, coupling j 0 the fitting body 22 and the fitting bonnet 24 at circular interface 31, and then coupling 108 the fitting body 22 and the fitting bonnet 24 by a metal coupling. As noted above, the initial step of coupling 1 6 the fitting body 22 and the fitting bonnet 24 at a circular interface 31 is, in an exemplary embodiment, the step of threadably coupling 107 the fitting body 22 and the fitting bonnet 24 at their respecti ve threaded proximal ends 30, 40.

in an exempl ary embodiment, and in view of the dimensions noted above, the step of providing 100 refrigeration ball valve fitting components includes the step of providing i 10 a fitting body 22 and a fitting bonnet 24 structured to have a circular interface 31 spaced between 0,34 inch and 0.54 inch, or about 0,44 inch, from the outer surface of the second ball seal 58", that is the ball seal 5S adjacent the circular interface 31. hi an exemplary embodiment, the step of coupling 108 the fitting body 22 and the fittins bonnet 24 bv a metal coupling includes utilizing a metal coup ling w ith a number of specific characteristics. It is understood that any number of these steps can be utilized alone or in conjunction with each other. Accordingly, the step of coupling 108 the fitting bod 22 and the fitting bonnet 24 by a metal coupling includes the step of applying 120 heat to the circular interface 31 with a welding dwell time of between about twel ve and twentv-five seconds, or about eiuhteen seconds. In an exemplary embodiment, the welding is accomplished by tungsten inert gas welding (hereinafter ' IG welding"). Thus, the step of coupling 108 the fitting body 22 and the fitting bonnet 24 by a. metal coupling includes the step of utilizing 124 a TIG welder (not shown). The step of coupling 108 the fitting body 22 and the fitt ing bonnet 24 by a metal coupling includes the step of mounting 126 the refri eration ball valve fitting components on a heat absorbing support 99 (Figure 4). In an exemplary embodiment, the heat absorbing support 99 is one of either a solid carbon steel support (not shown), a hollow copper support 97, or an aluminum support (not shown}. A solid carbon steel support acts as a heat sink. Use of a hollow copper support 97 further allows for the step of cooling 128 the refrigeration ball valve fitting components by passing a fluid through the hollow copper support 97. In an exemplary embodiment, the cooling fluid is passed through the hollow copper support 97 for less than a minute to about 15 minutes after the application of heat, i.e. after the use of the TIG welder has ceased. The use of the cooling fluid is, however, optional

In another exemplar embodiment, the step of mounting 126 the refrigeration ball valve fitting components on a beat absorbing support 99 includes the step of applying 129 a cooling fluid to the refrigeration ball valve fitting components. As shown in Figure 5, and in an exemplary embodiment, the heat absorbing support 99 includes a cooling fluid apparatus 80 structured to spray a cooling fluid over the refrigeration ball valve fitting components. As is known, the cooling fluid apparatus SO includes a support grate 82, a fluid reservoir 84, a pump 85, a number of fluid conduits 86 and a number of nozzles 88. In an exemplary embodiment, the cooling fl uid appara tus 80 applies water at a tempera ture of between about 4G°F to 50°F, or about 45° F. and is sprayed on the refrigeration ball valve fitting components at a rate of between about 1.0 to 2.0 gal./min., or about 1.5 ga!Jm .

In an exemplary embodiment, the step of utilizing 124 a TIG welder further includes the steps of: utilizing 130 a 2% Thoriated Tungsten steel electrode (not shown), positioning 132 the electrode between about 0.0005 inch and 0.005 inch, or about 0.002 inch, from the refrigeration ball valve fitting components for the duration of the welding dwell time, and powering 134 the electrode at between about 30 and 200 amps. In an exemplary embodiment, energy is supplied to the electrode at a variable rate. As used herein, the amount of energy supplied over period of time is an "energy profile." In an exemplary embodiment, the energy profile for the energy is supplied to the electrode is a "tapering-step energy profile." A "tapering-step energy profile" begins with a high energy that tapers briefly before becoming steady, i.e. plateauing, then tapering off again. In an exemplars' embodiment, the step of utilizing 124 a TIG welder includes the step of po wering 136 the electrode with a tapering-step energy profile that begins at about 200 amps, plateaus at about 150 amps, and decreases to about 30 amps, in an exemplary embodiment, the step of utilizing 124 a TIG welder includes the steps of rotating 138 the electrode about said circular interface at a speed of between about 6.0 to 12.5 seconds per inch, or about 9.0 seconds per inch, and, o ver a radial distance of between about 360 degrees and 390 degrees, or about 374 degrees.

While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and aitemati ves to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.