Patent Publication Number: US-2013228711-A1

Title: 3-Way Solenoid Valve

Description:
FIELD 
     The present disclosure relates to solenoid valves, and in particular to a pilot operated three-way solenoid valve. 
     BACKGROUND 
     This section provides background information related to the present disclosure, which is not necessarily prior art. 
     Solenoid actuated valves are commonly used to direct and selectively divert inlet flow between more than one delivery and/or output line. One exemplary use is with refrigeration heat reclamation, where hot refrigeration fluid or gas may be taken from the high pressure output from a compressor discharge and redirected for heat reclamation purposes. In normal operation, refrigeration fluid or gas typically flows from the compressor discharge to a downstream condenser inlet. When a solenoid actuated valve is used, the fluid or gas may be selectively diverted for heat reclamation purposes. 
     The operation of solenoid actuated valves with high pressure fluids and gases, however, may be prone to leakage. Leakage of refrigeration fluid or gas is highly undesirable. Accordingly, there remains a need for solenoid actuated valves with improved sealing techniques. 
     SUMMARY 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. 
     In one aspect of the present disclosure, a solenoid operated pilot valve is provided with a valve assembly including a valve seat and an impact absorbing floating plunger assembly. It may include a solenoid assembly configured to selectively raise and lower the impact absorbing plunger assembly. An upper valve body may be provided for receiving the valve assembly. A lower valve body may be coupled to the upper valve body and defining a cavity in fluid communication with an inlet source, a primary outlet, and a secondary outlet. The upper valve body and the lower valve body may be sealingly engaged to one another by a first sealing member, a second sealing member, and a third sealing member. A piston assembly may be disposed in the cavity, allowing selective fluid communication between the inlet source and either the primary outlet or the secondary outlet. Fluid may be directed from the inlet source to the primary outlet when the solenoid assembly is in a de-energized state, and fluid may directed from the inlet source to the secondary outlet when the solenoid assembly is in an energized state. 
     In another aspect, the present disclosure provides a solenoid operated pilot valve including a valve seat and an impact absorbing floating plunger assembly. The floating plunger assembly may include a slidable plunger body, a plunger pin seated within and configured to move with the plunger body, and a plunger spring biasing the plunger pin to sealingly engage the valve seat. A solenoid assembly may be provided configured to selectively raise and lower the plunger body. An upper valve body may be provided for receiving the valve assembly, and a lower valve body may be provided coupled to the upper valve body. The lower valve body may define a cavity in fluid communication with an inlet source, a primary outlet, and a secondary outlet. A piston assembly may be disposed in the cavity and allowing selective fluid communication between the inlet source and either the primary outlet when the solenoid assembly is in a de-energized state or the secondary outlet when the solenoid assembly is in an energized state. 
     In yet another aspect, the present disclosure provides a solenoid operated pilot valve comprising a valve assembly including a valve seat and a plunger assembly. A solenoid assembly may be provided configured to selectively raise and lower the plunger assembly. An upper valve body may be provided for receiving the valve assembly. The upper valve body may comprise a base portion that defines first and second annular grooves to retain respective first and second sealing members. A lower valve body may be configured to sealingly engage the base portion of the upper valve body and may define a third annular groove to retain a third sealing member. A cavity defined by the lower valve body may be provided in fluid communication with an inlet source, a primary outlet, and a secondary outlet. A piston assembly may be disposed in the cavity and may allow selective fluid communication between the inlet source and either the primary outlet or the secondary outlet. 
     Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
         FIG. 1  illustrates a first perspective view of an exemplary three-way solenoid valve according to various aspects of the present disclosure; 
         FIG. 2  illustrates a second perspective view of an exemplary three-way solenoid valve according to various aspects of the present disclosure; 
         FIG. 3  illustrates a side plan view of an exemplary three-way solenoid valve according to various aspects of the present disclosure showing the inlet and primary outlet; 
         FIG. 4  illustrates a side plan view of an exemplary three-way solenoid valve according to various aspects of the present disclosure showing the inlet, primary outlet, and secondary outlet; 
         FIG. 5  illustrates a top plan view of an exemplary three-way solenoid valve according to various aspects of the present disclosure; 
         FIG. 6A  illustrates a cross-sectional view of the solenoid valve taken along the line  6 A- 6 A of  FIG. 5  in a de-energized state; 
         FIG. 6B  illustrates a cross-sectional view of the solenoid valve taken along the line  6 B- 6 B of  FIG. 5  in a de-energized state; 
         FIG. 7  illustrates a magnified cross-sectional view of a portion of the solenoid valve in a de-energized state as indicated by the dashed circle  7  in  FIG. 6A ; 
         FIG. 8  illustrates a cross-sectional view of the solenoid valve taken along the line  6 A- 6 A of  FIG. 5  in an energized state; 
         FIG. 9  illustrates a magnified cross-sectional view of a portion of the solenoid valve in an energized state as indicated by the dashed circle  9  in  FIG. 8 ; and 
         FIG. 10  illustrates a perspective view of the valve housing assembly including an upper valve portion and a lower valve portion according to various aspects of the present disclosure. 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. 
     Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. 
     The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
     When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments. 
     Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. 
     The present disclosure relates to a solenoid operated pilot valve, and more specifically, to a three-way solenoid pilot valve. As shown with reference the various figures, a solenoid assembly  20  is provided and includes an input passage  22 , a first or primary outlet  24 , and a second or auxiliary outlet  26 . With regard to the specific illustrations provided herein,  FIGS. 1 and 2  provide perspective views of the solenoid assembly  20 , and  FIGS. 3-5  provide corresponding plan views.  FIGS. 6-9  provide various cross-section and magnified views; and  FIG. 10  provides a perspective view of the valve housing assembly. 
     In various aspects, the three-way solenoid pilot valve  20  can be used in heat reclamation techniques related to compressor usage, and the like. By way of example, the input passage  22  may in fluid communication with a high pressure output from a compressor discharge. In normal operation, a fluid or gas, for example a refrigerant fluid or gas, may normally flow from a compressor discharge (not shown) to the inlet passage  22  where it is typically directed to a downstream condenser inlet (not shown) via the primary outlet  24 . The three-way solenoid pilot valve  20  of the present disclosure may, when the solenoid is energized, selectively divert the flow of fluid from the compressor discharge to a heat reclamation unit (not shown) via the secondary outlet  26 . It should be noted that the reference to the outlets as “primary” and “secondary” may be interchanged. In various aspects, however, it may be beneficial to have the discharge to the heat reclamation located at the elevated output as this may allow for free draining flow of refrigerant to the condenser. As should be apparent to one of ordinary skill in the art, the use of a three-way solenoid valve with refrigeration heat reclamation is just one of many non-limiting uses for the present technology. 
     The solenoid pilot valve assembly  20  may include a coil actuation assembly  28  and a valve housing assembly  30 . The valve housing assembly may include an upper valve body  32  for receiving a valve assembly and a lower valve body  34  removably coupled to the upper valve body  32  with a plurality of bolts  36 . The valve housing assembly  30 , as well as other components of the assembly  20  may be made of brass. A capillary tube connector  23  may be provided in fluid communication between the inlet source  22  and an internal area of the valve assembly. For example, the capillary tube connector  23  may be brazed to the lower valve body  34  such that fluid or gas may be directed through a wall of the lower valve body  34  and into an internal passage  25  disposed within the upper valve body  32  leading to the valve seat  68 . 
     The coil actuation assembly  28  may include a suitable solenoid coil  56  and a shading ring  57  as is known in the art. The coil actuation assembly  28  may utilize a removable snap-on type of design for fitting with the remainder of the solenoid assembly  20 . A top plug  38  may be inserted at the top of the assembly  28  with a fastening device, such as a snap cap  39 . 
     An impact absorbing floating plunger assembly may be provided disposed within a bottom portion of the coil actuation assembly  28 . The impact absorbing plunger assembly may include a slidable plunger body  58  disposed within a plunger enclosure tube  59 , and a floating plunger pin  62  disposed within the plunger body  58 . An upper portion of the plunger enclosure tube  59  may couple with the top plug  38  and/or snap cap  39 , while a lower portion of the plunger enclosure tube  59  may couple to a collar member  42  using a solder ring fitting  60 , or other suitable fastening means. The collar member  42  may be coupled to the upper valve body  32  and a suitable sealing member  43  may be provided therebetween. In various aspects, the collar member  42  may threadedly engage the upper valve body  32 . 
     A plunger pin  62  may be seated within a slidable plunger body  58  using an appropriate annular seat  63  or other stop means such that the plunger pin  62  and is configured to move up and down corresponding with movement of with the slidable plunger body  58 . A biasing member, such as a plunger spring  64 , may be provided to bias the plunger pin  62  to sealingly engage a valve seat  68 , as will be discussed in detail below. For example, the plunger pin  62  may be provided with a spring seat, and the plunger spring  64  may extend from the plunger pin  62  up to the top plug  38 . As best shown in  FIGS. 7 and 9 , the plunger spring  64  is disposed between the plunger pin  62  and the top plug  38  and allows the plunger pin  62  to “float” above the valve seat  68  if necessary to absorb any impact. For example, in addition to the plunger pin  62  being configured to move up and down with corresponding movement of the plunger body  58 , it is also able to independently move in an upwards direction, i.e., temporarily lift off of the valve seat  68  due to unexpected pressure fluctuations, without corresponding movement of the plunger body  58 . Once lifted, the plunger spring  64  may then bias the plunger pin  62  back to a sealing position on the valve seat  68 . Such a floating design may decrease wear and increase the life of the valve. For example, when the coil is in a de-energized state, only the mass of the plunger pin  62  and plunger spring  64 , along with the force of the plunger spring  64 , impacts the valve member  66 . The mass of the plunger body  58  is not involved with the impact of the valve member  66  on the valve seat  68 . 
     As shown in  FIG. 7 , in one non-limiting example, the end of the plunger pin  62  may be provided with a curved or substantially ball shaped pilot valve  66  structure configured to seal with the valve seat  68 . In one aspect, the ball shaped pilot valve  66  may be substantially spherical in shape. The pilot valve  66  may be formed with the plunger pin  62  as one integral or monolithic component. In various aspects, the pilot valve  66  and plunger pin  62  may be formed from hardened stainless steel. It is believed the floating design of the present technology can offer various benefits to the solid plunger pressed pins of the prior art, for example, by minimizing stress and fatigue that may occur during normal cycling operations of the valve. If a solid plunger is used and inserted or press fit into a valve seat, for example, the tolerances may change over time by repeated contact with the valve seat, which may eventually increase the potential for leakage. 
     The upper valve body  32  may be provided with a top portion  31  and a base portion  33 . As best shown in  FIG. 10 , the base portion  33  may be cylindrical, although other geometries may be used, with the understanding that it will provide a suitable seal with the lower valve body  34 . The top portion  31  of the upper valve body  32  may be provided with a suction outlet  40  that may be connected to a location downstream of one of the primary or secondary outlets, for example, at a location near a compressor input. 
     The lower valve body  34  defines a cavity  77  that provides fluid communication between the inlet source  22  and either the primary outlet  24  or the secondary outlet  26 . As illustrated, the lower valve body  34  may be configured to sealingly engage both the base portion  33  and top portion  31  of the upper valve body  32  with at least three sealing members  70 ,  72 ,  74 . With renewed reference to  FIG. 10 , the base portion  33  may include a first annular groove  71  to retain a first sealing member  70  to form a primary seal. A second annular groove  73  may be provided in the base portion  33  to retain a second sealing member  72  to form a secondary seal. An upper and substantially planar surface  35  of the lower valve body may define a third annular groove  75  to retain a third sealing member  74  to form a tertiary seal. With reference to  FIGS. 7 ,  9 , and  10 , the first and second annular grooves inwardly extend a distance in the Y direction of an X-Y plane, while the third annular groove inwardly extends a distance in the X direction of the same X-Y plane. 
     In various aspects, the sealing members  70 ,  72 ,  74  may comprise various O-rings and gaskets fabricated from known materials, such as polymers including neoprene, polytetrafluoroethylene (PTFE) or Teflon, and mixtures and combinations thereof. By way of example, the primary and secondary sealing members  70 ,  72  may be neoprene fabricated o-rings, and the tertiary sealing member may be a PTFE fabricated gasket. 
     A piston assembly may be disposed in the cavity  77  and can include a piston rod  44  coupled to an upper piston  46  including an upper piston seal  47  and a lower piston  48  including a lower piston seal  49 . The lower piston  48  may be attached to the piston rod  44  with a nut  52  or other mechanical fastener. As shown, the lower piston  48  may include a lower cap surface  50  configured to sealingly engage an upper seating surface  51  adjacent the primary outlet  24 , and an upper cap surface  54  to sealingly engage a lower seating surface  55  of a divider member  45  disposed within the cavity  77 . The divider member  45  cooperates with the lower piston  48  to selectively seal portions of the cavity  77  and to direct flow to the appropriate outlet  24 ,  26  depending on the pilot valve position (i.e., the energized versus the de-energized states). 
     The upper piston  46  may be separated from the base portion  33  of the upper valve body  34  by a biasing member, such as a piston spring  78 . The area between the upper piston  46  and the upper valve body  34  may define a piston spring chamber  76 . The base portion  33  of the upper valve body  34  may include a pilot hole  80  or passageway providing fluid communication between the suction outlet  40  and the piston spring chamber  76 . 
     With renewed reference to  FIG. 10 , which illustrates the valve housing assembly  30  components, the upper valve body  32  may include a plurality of bores  86  configured to mate with corresponding bores  88  formed in the lower valve body  34 . Mechanical fasters, such as bolts, can be used to removably couple the valve bodies. It should be understood that the lower valve body  34  may include additional various bores to connect with the various inlets and outlets that may be used. For example, bore  82  is configured to connect with the capillary tube input  23 , while bore  84  is configured to connect to inlet tube  22 . Similar bores (not shown) on other sides of the lower valve body  34  may also be used for connection with the primary outlet  24  and secondary outlet  26 . As should be understood to those skilled in the art, alternative designs can be used, including integrally formed inlets and outlets, without deviating from the scope of the present disclosure. 
     Now turning to the operation of the three-way solenoid valve assembly  20 , when the coil  56  is de-energized, the valve is in a normal operation mode and high pressure gas or fluid may enter the inlet  22  and be diverted through the primary outlet  24  and to a condenser, or the like (not shown). In this mode, the plunger body  58  is in a downward, normal position as shown in  FIGS. 6A ,  6 B and  7 . The plunger spring  64  biases the plunger pin  62  down such that the ball valve member  66  sealingly engages the valve seat  68 . The piston assembly is in a raised, upward position in the cavity  77  and is maintained in such position by the pressure from the incoming fluid or gas. For example, as shown in  FIG. 6A , the upper cap surface  54  of the lower piston  48  engages the lower seating surface  55  of the divider  45 , and the lower piston seal  49  prevents the fluid or gas from entering the secondary outlet  26 , and only allowing the fluid to exit through the primary outlet  24 . The pressure forces the piston spring  78  to be in a compressed state as the upper piston  46  is moved adjacent to the base portion  33  of the upper valve body  32 . The piston spring chamber  76  is connected to the suction outlet  40  through the pilot hole  80 . This causes a lower pressure area above the piston as compared to that below, keeping the piston assembly from shifting downward. 
     When the solenoid coil  56  is energized, however, the plunger body  58  is raised by magnetic force to abut with the top plug  38 . The plunger pin  62  is concurrently raised by the upward movement of the plunger body  58  and the ball valve member  66  is lifted from the valve seat  68  as shown in  FIGS. 8 and 9 . The suction outlet  40  is closed from fluid communication with the valve. Fluid or gas from the capillary input tube  23  passes through the internal passage  25  of the upper valve body  32  and is allowed to pass through the valve to enter the piston spring chamber  76  via the pilot hole  80 . The high pressure fluid or gas input, when combined with the biasing force of the piston spring  78 , pushes the piston assembly downward to seal the primary outlet  24  as shown in  FIG. 8 . For example, the lower cap surface  50  of the lower piston  48  engages the upper seating surface  51  of the entrance to the primary outlet  24 , and the lower piston seal  49  prevents the fluid or gas from entering the primary outlet  24 , and only allowing the fluid or gas to exit up and out through the secondary outlet  26 . 
     When the solenoid coil  56  is thereafter de-energized, the magnetic force no longer keeps the plunger body  58  in a raised position. The plunger spring  64  biases the plunger pin  62  back downward along with the plunger body  58  and the ball valve member  66  is reseated on the valve seat  68 . Fluid from the capillary tube  23  is no longer able to pass through the internal passage  25  of the upper valve body  32  and to the valve. The suction outlet  40  opens and draws any remaining fluid from the piston spring chamber  76  out via the pilot hole  80 , which raises the piston assembly upward. The upper cap surface  54  of the lower piston  48  is again biased against the lower seat  55  of the divider  45 , closing access to the secondary outlet  26  and diverting fluid back to the primary outlet  24 . High pressure keeps the piston assembly in the upward position until the solenoid is re-energized, or until incoming fluid or gas stops flowing to the three-way solenoid valve assembly. 
     If the flow of incoming fluid or gas stops, and the solenoid is de-energized, the piston assembly may fall back to the downward position. Alternatively, if suction is still provided via the suction outlet when flow of incoming fluid or gas stops, the piston assembly may remain in the upward position. 
     The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.