Patent Publication Number: US-2012025124-A1

Title: Service valve body

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application claims the benefit of the filing date of U.S. Provisional Patent Application Ser. No. 61/368,291, filed Jul. 28, 2010, the disclosure of which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     A service valve body (part of condensing unit assembly) for a residential heating/cooling system (such as an air conditioning system or heat pump system) can be assembled by brazing copper field and factory stems to a brass body. Various configurations of the service valve body can include: a barstock body with a charge stem and two copper stems brazed in, a forged body with a charge stem and two copper stems brazed in, or a forged body with a charge stem forged with body and two copper stems brazed in. Each of these configurations requires the stems to be brazed, either by furnace or by torch. Brazing can be a very expensive manufacturing process, and can create additional cost due to scrap, rework, and customer returns. 
     SUMMARY 
     The present invention provides a brazeless service valve body in which the components of the valve body, including the field and factory stems, are monolithic with one another. The service valve body does not have any brazed connections, seams, or joints. Elimination of the brazing process can lower the manufacturing cost of and reduce the amount of floor space necessary to build service valves in a manufacturing facility. Additionally, eliminating brazed connections, seams and joints from the valve body can increase the reliability of the service valve by eliminating potential leak paths through the valve body. 
     According to another aspect, the charge port stem contains a valve stem. The charge port stem and valve stem are angled relative to the axis of the first and/or second stems. In this manner, the service valve is easier for a technician to access for servicing the heating/cooling system. 
     According to one embodiment, the present invention provides a service valve body having a main body with an internal chamber. A charge port stem extends from the main body and has an opening and a passageway that is in fluid communication with the internal chamber. The valve body also has first and second stems that extend from the main body. The first stem has a passageway that is in fluid communication with the internal chamber and a distal end portion having an opening to the passageway. The second stem also has a passageway that is in fluid communication with the internal chamber and a distal end portion having an opening to the passageway. The main body, the first stem, the second stem, and the charge port stem are monolithic with one another. 
     According to one aspect, the first stem extends along a first axis and the charge port stem extends along an axis that is angled relative to the first axis. The first axis and the charge port axis may be in the same plane, or may be in planes that are perpendicular to one another. 
     According to another aspect, the main body is mated with a valve core to form a service valve. 
     To the accomplishment of the foregoing and related ends, the invention comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The appended drawings show various features of embodiments of the invention. 
         FIG. 1  is an isometric view of an embodiment of a service valve body. 
         FIG. 2  is a side elevation view of the service valve body of  FIG. 1 . 
         FIG. 3  is a front elevation view of the service valve body of  FIG. 1 . 
         FIG. 4  is a section view of the service valve body taken along lines A-A of  FIG. 3 . 
         FIG. 5  is an isometric view of another embodiment of a service valve body. 
         FIG. 6  is a side elevation view of the service valve body of  FIG. 5 . 
         FIG. 7  is a front elevation view of the service valve body of  FIG. 5 . 
         FIG. 8  is a section view of the service valve body taken along lines B-B of  FIG. 7 . 
         FIG. 9  is a section view of the service valve body taken along lines C-C of  FIG. 7 . 
         FIG. 10  is a sectional view of an exemplary embodiment of a service valve installation having a service valve body substantially the same as that shown in  FIGS. 1-4 . 
     
    
    
     DETAILED DESCRIPTION 
     An exemplary embodiment of a service valve body  10  is shown in  FIGS. 1-4 . The service valve body  10  has a main body  12 . Extending from the main body  12  is a first stem  16 , a second stem  18 , and a charge port stem  20 . The main body  12 , first stem  16 , second stem  18  and charge port stem  20  are monolithic with one another (e.g., formed from a one-piece construction). The valve body  10  is free from any joints between the main body  12  and the stems. For example, the first stem  16 , the second stem  18  and the charge port stem  20  extend from the main body  12  in a brazeless and seamless manner. 
     The service valve body  10  may be formed by a forging process. For example, a block of material may be forged into the rough outer shape of the main body  12 , the first stem  16 , the second stem  18  and the charge port stem  20 . The valve body  10  can then be formed by a machining process, with the various passageways through the valve body being formed by machining bores through the stems. Other alterative manufacturing processes are also possible. For example, the valve body can be formed from a casting process with the various passageways through the stems being preformed by the casting. The valve body can then be machined into its final shape. As another alternative, the valve body can be manufactured by metal injection molding. Suitable metals for forming the valve body may include brass, aluminum, steel, and the like. Alternatively, the valve body may be formed from a plastic material, for example, by an injection molding process. 
     The various bores (described below) through the valve body  10  are connected to one another by an internal chamber  22  in the main body  12 . The internal chamber  22  may be formed by a bore  24  in the main body  12  having an opening  25  through which a valve core can be inserted to form a service valve (see  FIG. 10 ). The bore  24  may be configured to engage the valve core, for example, the bore  24  may have threads  26  and a shoulder  28  that provides a seat for the valve core and/or other internal components of the service valve (e.g., an elastomeric element, such as an O-ring). 
     As shown in  FIGS. 1-4 , the service valve body  10  has a base  30  at the opposite end of the opening  25 . The base  30  may be monolithic with the main body  12  and may include one or more installation holes  32  for connecting the service valve body to another structure, for example, a structure within an air conditioning unit. Alternatively, the base may be formed separately from the main body, and the base and the main body may be coupled together by a weld, a connector, and/or another connecting mechanism. 
     One of the stems (e.g., the first stem  16 ) extends from a side of the main body  12  between the opening  25  and the base  30 . The first stem  16  has a bore  40  that forms a passageway through the stem from an opening  42  at a distal end portion  44  of the stem to the internal chamber  22  such that the passageway is in fluid communication with the internal chamber. As shown in  FIG. 2 , the first stem  16  extends along axis  46 . The bore  40  in the first stem  16  may include a shoulder  48  that provides a surface against which a conduit of a heating/cooling system may abut when the service valve is installed. 
     As shown in the embodiment of  FIG. 1 , the other stem (e.g., the second stem  18 ) extends from the main body  12  between the opening  25  and the base  30 . The second stem  18  may extend from a side of the main body  12  opposite the first stem  16 , although other configurations are possible. The second stem  16  has a bore  50  that forms a passageway through the second stem  18  from an opening  52  at a distal end portion  54  of the stem to the internal chamber  22  such that the passageway is in fluid communication with the internal chamber. As shown in  FIG. 2 , the second stem  16  extends along axis  56 . The second stem axis  56  may be parallel to the first stem axis  46 . The bore  50  in the second stem  18  may include a shoulder  58  that provides a surface against which a conduit of a heating/cooling system may abut when the service valve is installed in the system. 
     One of the stems may be a factory stem that is coupled to a conduit by a manufacturer of the heating/cooling system, and the other stem may be a field stem that is coupled to a conduit during installation of the heating/cooling system. 
     The distal end portion  44  of the first stem  16  and/or the distal end portion  54  of the second stem  18  can be configured for brazing the stem to a conduit of a heating/cooling system. For example, the distal end portion of the stem can be threadless. Additionally or alternatively, the distal end portion of the bore may include copper flashing to facilitate brazing of the stem to a copper conduit. Such brazed connections can be more reliable than threaded connections, which require fittings that can introduce leak paths and/or can be subject to failure. 
     If the valve body is formed from plastic, the distal end portions of the stems can be configured for connection to the conduits of the heating/cooling system by one or more fittings, such as compression fittings, quick couplers, and the like. 
     The distal end portions  44  and  54  of the stems  16  and  18  are spaced from the main body  12 . As noted above, the internal chamber  22  in the main body  12  may contain heat-sensitive elements (such as O-rings or other elastomeric elements and the like). During installation, the first stem  16  and second stem  18  are typically brazed to the copper conduits of the heating/cooling system. Spacing the distal end portions of the stems from the main body reduces the likelihood that heat from brazing the conduit(s) to the valve body will damage the heat-sensitive elements contained therein. 
     The length of the first stem  14  and/or second stem  16  may be about 0.5 inches to about 2 inches as measured from the opening at the distal end of the stem to an outer wall of the main body (e.g., the length of the first stem  16  is measured from the opening  42  to an outer wall  60  of the main body  12 , and the length of the second stem  18  is measured from the opening  42  to an outer wall  62  of the main body  12 ). In one embodiment, the length of the first stem and/or second stem is about 1.5 inches. 
     Also extending from the main body  12  is the charge port stem  20 . The charge port stem  20  has a passageway  70  that is in fluid communication with the internal chamber  22  of the main body  12 . The passageway  70  has an opening  72  at a distal end portion  73  of the charge port stem  20 . The charge port stem also has a valve stem  74  disposed in the passageway  70 . Refrigerant can be added or evacuated from the heating/cooling system through the valve stem  74  by coupling the valve stem  74  to a fluid supply line or vacuum line. As shown in  FIG. 2 , the charge port stem  20  and the valve stem  74  contained therein extend along axis  76 . 
     The charge port stem axis  76  may be angled relative to the axis  46  of the first stem  16  and/or the axis  56  of the second stem  18 . In one embodiment, the charge port stem axis  76  is in the same plane as the first stem axis  46 . The charge port stem axis  76  may extend along an axis that is between about 30°-about 60° relative to the first stem axis  46 . In the embodiment of  FIGS. 1-4 , the charge port stem axis  76  is angled about 45° relative to the axis of the first stem axis  46 . 
     The angled charge port stem  20  can facilitate service of the heating/cooling system in which the service valve is installed. For example, it may be difficult for a technician to access a valve stem to charge/evacuate the system when the service valve is installed in a tight location of an air conditioner unit. By angling the charge port stem  20  (e.g., as shown in  FIG. 1 ), the valve stem  74  is easier to access and therefore service of the heating/cooling system can be less cumbersome. 
     As shown in the embodiment of  FIGS. 5-9 , the charge port stem axis  76  can be perpendicular to the first stem axis  46  and/or the second stem axis  56 . As shown, the charge port stem axis  76  is located in a plane that is perpendicular to the plane containing the first stem axis  46 . Other than the location and orientation of the charge port stem, the valve body of  FIGS. 5-9  is the same as that shown in  FIGS. 1-4 , and therefore for brevity the details will not be repeated. 
     Referring now to  FIG. 10 , a service valve  80  is shown. The service valve  80  has a valve core  86  (shown schematically) contained in a service valve body  10 . In the illustrated embodiment, the service valve body  10  is substantially the same as the service valve body shown in  FIGS. 1-4  although other configurations are possible, such as that shown in  FIGS. 5-9 . 
     The service valve  80  is shown coupled to conduits  82  and  84  of a heating/cooling system. The service valve  80  is installed into the heating/cooling system by brazing the distal end portion  44  of the first stem  16  and the distal end portion  54  of the second stem  18  to respective conduits  82  and  84  of the system. As noted above, the distal end portions  44 ,  54  of the first and second stems  16 ,  18  can be configured to facilitate the brazing of the service valve to copper conduits. For example, the bores may be coated with copper flashing to facilitate brazing of the stems to copper conduits. 
     The valve core  86  can be coupled to the main body  12  by a threaded connection. The valve core can be open/closed to start and stop the flow of refrigerant through the system during service of the system (e.g., when the system is being charged with refrigerant, or when the system is being evacuated). 
     Although the principles, embodiments and operation of the present invention have been described in detail herein, this is not to be construed as being limited to the particular illustrative forms disclosed. They will thus become apparent to those skilled in the art that various modifications of the embodiments herein can be made without departing from the spirit or scope of the invention. The features described with respect to one embodiment can be combined with features described with respect to another embodiment.