Patent Publication Number: US-10760685-B2

Title: Pump shaft packing gland and bushing

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application Ser. No. 62/406,472, entitled FLOATING BUSHING AND PACKING GLAND, filed Oct. 11, 2016; and claims priority to U.S. Provisional Patent Application Ser. No. 62/474,217, entitled SLIP FIT BUSHING WITH INTEGRAL O-RING SHAFT SEAL, filed Mar. 21, 2017, both of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     Fluid pumps used in a variety of settings often utilize a packing seal system, which can comprise packing material and a packing gland, to mitigate loss of the transported fluid from the fluid transport system. These sealing systems are typically implemented along a rotating shaft used to drive the pumping component. For example, packing material can be compressed against a back seat, on a rotating shaft, by the packing gland and follower components. Often, a separate bushing component may be disposed on the shaft, between the packing gland and packing material. In this way, for example, the compressed packing material, along with a pressurized lubricant and bushing, can help mitigate fluid loss along the shaft. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key factors or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. 
     One or more techniques and systems described herein can be utilized to help mitigate fluid loss or leakage from a fluid pump with a rotating shaft driving a pumping mechanism, such as in a gear pump, for example. In one implementation, a packing gland component and bushing component may be formed as a one-piece, packing gland-bushing component, instead of typical two-piece components. In this example, the packing gland-bushing component can have an internal seal that allows for use of lubricants at higher pressures. Further, in this implementation, a face of the packing gland portion may have removal components that allows for easier removal of the packing gland-bushing component from a pump shaft. 
     As another example, the one-piece packing gland-bushing may be configured to be used without packing material, essentially comprising merely a bushing component. In this example, the packing gland-bushing component may have a slip-fit configuration with the shaft of the pump. For example, a plurality of O-rings may be used to provide a seal, and allow for pressurized lubricant to be introduced along the bushing portion, at higher pressures. In some configurations, this may allow for the elimination of packing material in the shaft seal. 
     In one implementation of a system for sealing a pump shaft, a one-piece, combination packing gland and bushing component can be used to seat in a shaft casing along a rotating pump shaft. In this implementation, the packing gland and bushing component can comprise a proximal end that is situated on the shaft near a pump motor coupler portion of the shaft, and a distal end that is situated distally on the shaft from the pump motor coupler. The packing gland and bushing component can further comprise a packing gland portion at the proximal end to provide for compression of packing material in the shaft casing. Additionally, the packing gland and bushing component can comprise a bushing portion at the distal end in order to provide a bearing surface for the rotating shaft. In this implementation, the bushing portion can comprise an inner gasket channel that is disposed proximate a proximal end of the bushing portion. The inner gasket channel can be used hold a gasket between the inside of the bushing portion and the rotating shaft to mitigate leakage of a lubricant from the proximal end of the inside of the bushing portion. In this implementation, a packing material can be disposed proximate the distal end of the packing gland and bushing component to mitigate leakage of a fluid from a pumping chamber. The packing material can be subjected to compression force that is provided by the packing gland and bushing component. 
     To the accomplishment of the foregoing and related ends, the following description and annexed drawings set forth certain illustrative aspects and implementations. These are indicative of but a few of the various ways in which one or more aspects may be employed. Other aspects, advantages and novel features of the disclosure will become apparent from the following detailed description when considered in conjunction with the annexed drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a component diagram illustrating a view of an example implementation of a pump where one or more portion of one or more systems described herein may be implemented. 
         FIGS. 1B and 1C  are a component diagrams illustrating a cut-away view of an example implementation of a pump where an example system  100 , described herein, may be implemented. 
         FIGS. 2A and 2B  are component diagrams illustrating various views of one or more portions of one or more systems described herein. 
         FIGS. 3A and 3B  are component diagrams illustrating various views of one or more portions of one or more systems described herein. 
         FIG. 4  is a component diagram illustrating a view of an example implementation of a pump where one or more portion of one or more systems described herein may be implemented. 
         FIG. 5A  is a component diagram illustrating a view of an example implementation of a pump where one or more portion of one or more systems described herein may be implemented. 
         FIGS. 5B and 5C  are a component diagrams illustrating a cut-away view of an example implementation of a pump where an example system  100 , described herein, may be implemented. 
         FIG. 6  is a component diagram illustrating a perspective view of an example device  600  used to facilitate providing a seal in a pump. 
         FIG. 7  is a component diagram illustrating a perspective cut-away view of an example device  600  used to facilitate providing a seal in a pump. 
         FIG. 8  is a component diagram illustrating a view of an example implementation of a pump where one or more portion of one or more devices described herein may be implemented. 
         FIG. 9  is a component diagram illustrating a cut-away view of an example implementation of a pump where one or more portion of one or more devices described herein may be implemented. 
         FIG. 10  is a component diagram illustrating a cut-away view of an example implementation of a pump where one or more portion of one or more devices described herein may be implemented. 
         FIG. 11  is a component diagram illustrating a close up of a cut-away view of an example implementation of a pump where one or more portion of one or more devices described herein may be implemented. 
     
    
    
     DETAILED DESCRIPTION 
     The claimed subject matter is now described with reference to the drawings, wherein like reference numerals are generally used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the claimed subject matter. It may be evident, however, that the claimed subject matter may be practiced without these specific details. In other instances, structures and devices are shown in block diagram form in order to facilitate describing the claimed subject matter. 
     As an example, pumps can be coupled to a motor by a rotating shaft. The motor typically rotates the shaft, which, in turn, rotates a pump rotor to move the fluids through coupled conduits. However, the location at which the rotating pump shaft enters the pumping chamber, comprising the pump rotor, offers a location for leakage of the pumped fluid from the pump chamber. A system can be devised for sealing a rotating pump shaft entrance to the pumping chamber. In one implementation, the pump can comprise a pump shaft casing, or pump shaft packing box, or the like, disposed proximally (e.g., proximally in relation to the connection of the shaft to the motor) from the entrance of the pump shaft to the pump chamber. In this implementation, the pump shaft is disposed inside the pump shaft casing, or pump shaft packing box, etc. 
       FIGS. 1-5  illustrate one implementation of an example system for sealing a rotating pump shaft in a pump.  FIG. 1A  illustrates an example pump  50 , in an elevation, rear view from the pump&#39;s motor toward the pump rotor.  FIG. 1B  illustrates one implementation of a system  100 , showing the example pump  50  in a top a cut-away view, along the A-A line of  FIG. 1A .  FIG. 1C  illustrates one implementation of a system  100 , showing the example pump  50  in a close up of a portion of the top a cut-away view of  FIG. 1B . In this implementation, a one-piece, combination packing gland and bushing component  102  can be used to seat in a shaft casing  150  along a rotating pump shaft  152 . In this implementation, the packing gland and bushing component  102  can comprise a proximal end  104  that is proximate a pump motor coupling portion  162  of the shaft  152 . Further, the packing gland and bushing component  102  can comprise a distal end  106  that is distal from the pump motor coupling portion  162  of the shaft  152 . 
     Additionally, in this implementation, the packing gland and bushing component  102  can comprise a packing gland portion  108  disposed at the proximal end  104 . The packing gland portion  108  can provide for compression of packing material in the shaft casing  150 . The packing gland and bushing component  102  can also comprise a bushing portion  110  that is disposed at the distal end  106 . The bushing portion  110  can provide a bearing surface  114  for the rotating shaft  152 . In this implementation, the bushing portion can comprise an inner gasket channel  116  that is disposed proximate a proximal end of the bushing portion  110 . The inner gasket channel  116  can be used to hold a gasket between the inside of the bushing portion  110  and the rotating shaft  152  to mitigate leakage of a lubricant from the proximal end  104 , from the inside of the bushing portion  110 . 
     As illustrated in  FIGS. 1B and 1C , the example system  100  can comprise packing material  112  that is disposed proximate the distal end  106  of the packing gland and bushing component  102 . The packing material  112  can be used to mitigate leakage of a fluid from a pumping chamber  154 . Further, in this implementation, the packing material  112  can be subjected to compression force provided by the packing gland and bushing component  102 . As illustrated in  FIGS. 3A and 3B , with continued reference to  FIGS. 1B and 1C , in one implementation, the gland portion  104 , of the packing gland and bushing component  102 , can comprise two fastener couplers  302 . In this implementation, the fastener couplers  302  can respectively be configured to receive a compression fastener  158  to facilitate compression of the packing material (e.g., against a packing retainer or rear seat of a packing chamber or shaft casing), such as by using the packing gland and bushing component  102 . In one implementation, the pump can comprise a packing retainer, which may be removable from the pump rotor side of the shaft casing or packing chamber. In this way, for example, the packing material  112  may be removed (e.g., and replaced) without removal of the packing gland and bushing component  102 . 
     As an example, the combination packing gland and bushing component  102  may be used to replace current two-piece bushing and packing gland systems in the shaft casing of a fluid pump. For example, two-piece packing gland systems, which are often made of two different materials, can be more difficult to remove from the shaft casing, for maintenance, and/or replacement of packing material. That is, using the example system  100 , both the packing gland and bushing portions  108 ,  110  can be removed at the same time; and a one-piece, combination packing gland and bushing component  102  can be easier and less costly to manufacture in a single unit (e.g., machined, formed, etc.). Whereas current and prior two-piece systems have two separate pieces that are manufactured separately (e.g., and sometimes using different materials), and may need to be removed separately. Further, for example, the location of the inner gasket channel  116 , with an accompanying gasket (e.g., O-ring), may allow for higher pressures of shaft lubricant pressure without causing typical lip seal failure of bushing found in current two-piece systems. 
       FIGS. 2A, 2B, 3A, 3B, 4, 5A, 5B, and 5C  illustrate various views of one or more implementations of one or more portion of the example system  100 , as may be utilized in an example pump  50 . In one implementation, the packing gland and bushing component  102  can comprise an outer gasket channel  118  that is disposed proximate the proximal end  102  of the bushing portion  110 . In this implementation, the outer gasket channel  118  can be used to hold an outer gasket  210  between the outside of the bushing portion  110  and a wall of the shaft casing  156 . As an example, the outer gasket channel  118  with the outer gasket  210  can help mitigate leakage of lubricant (e.g., and/or pumped fluid) from the proximal end  104  of the packing gland and bushing component  102 , around the external surface  204  of the bushing portion  110 . 
     In one implementation, as illustrated in  FIGS. 2A and 2B , the packing gland and bushing component can comprise a lubricant channel  202  that is disposed around the external surface  204  of the bushing portion  110 , distally on the bushing portion  110  from the inner gasket channel  116 . The lubricant channel  202  can be configured to operably receive bushing lubricant  160 , such as provided by a lubricant source (e.g., injector). Further, in this implementation, the packing gland and bushing component  102  can comprise a lubricant port  206  that is disposed through a wall  306  of the bushing portion  110 , between the lubricant channel  202  and the interior of the bushing  308 . The lubricant port  206  can be configured to operably transport lubricant  160  from the lubricant channel  202  to the interior of the bushing portion  308 . 
     As one example, the pump (e.g.,  50 ) may comprise a lubricant provider, such as lubrication pump, injector, or the like, that provides a lubricant source. In this example, the lubricant source can be fluidly coupled with a port located in the wall  156  of the shaft casing  150 . Further, in this example, the port located in the wall  156  of the shaft casing  150  may be aligned with the lubrication channel  202 , thereby providing a source of lubricant to the lubrication channel  202 . Additionally, the lubrication port  206  can provide a fluid channel for the lubricant between the lubrication channel  202  and the interior of the bushing portion  308 . In this way, for example, the bearing surface  114  of the bushing portion  110  can be provided with lubrication, at least while the shaft  152  is operably rotating during operation of the pump  50 . 
     As one example, a location of the outer gasket channel  118 , used with an accompanying gasket  210 , can mitigate leakage of the lubricant to the proximal end  104  of the packing gland and bushing component  102 , along its outer surface  204 . Further, in this example, the location of the inner gasket channel  116 , used with an accompanying inner gasket  208 , can mitigate leakage of the lubricant to the proximal end  104  of the packing gland and bushing component  102 , along its inner surface (e.g., the bearing surface  114 ). Additionally, the location of these gaskets  208 ,  218 , in combination with the one-piece combination of the packing gland and bushing component  102  may allow for lubricant to be used at a higher pressure than prior. In this way, leakage of the pumped fluid from the pumping chamber  154  may also be mitigated by using higher lubricant pressures. As one example, the location of the gasket channel  116  and inner gasket  208  can provide a dynamic seal against the shaft  152 . In this example, lubricant provided to the interior of the bushing portion  308  can help cool and lubricate the gasket  208 . The gasket channel  116  and inner gasket  208  can also serve as a secondary containment to mitigate leakage from the pumping chamber  154 , for example, if the packing material  112  would fail. 
     In one implementation, as illustrated in  FIGS. 3A, 3B, and 4 , the packing gland and bushing component  102  can comprise a packing gland and bushing removal component  304 . In one implementation, the packing gland and bushing removal component  304  can be disposed on the packing gland portion  108  to facilitate removal of the packing gland and bushing component  102  from the pump shaft casing  150 . As an example, the packing gland and bushing removal component  304  can comprise an access opening that allows a pulling tool to engage with the packing gland portion  108 , to pull the packing gland and bushing component  102  from the pump shaft casing  150 . 
     In one implementation, the packing gland and bushing removal component  304  can comprise a threaded portion to further facilitate removal of the packing gland and bushing component  102 . For example, the access opening of the packing gland and bushing removal component  304  may comprise internal threads that allows for engagement with an external threaded component. In one example, jack screws may be threaded into the packing gland and bushing removal component  304  to facilitate in removal. As another example, a pulling tool can be coupled with the jack screws to provide for easy removal of the packing gland and bushing component  102 . 
     In one aspect, a device may be devised that can be used for sealing a pump shaft of a pump.  FIGS. 6-11  illustrate one or more portions of an example device  600 , in this aspect, and one or more implementations of the example device  600  as used in an example pump  854 . In one implementation, as illustrated in  FIGS. 6-10 , the example device  600  can comprise a tubular portion  602 . The tubular portion  602  can comprise a distal end  604  that may be disposed adjacent a back seat  1052  of a pump shaft packing box  950 . Further, in this implementation, the example device  600  can comprise a proximal end  606  that may be disposed adjacent a proximal end  952  of the pump shaft packing box  950 . That is, for example, the length of the tubular portion  602  can be configured to fit (e.g., and fill entirely) the length of the pump shaft packing box  950 . 
     In this implementation, tubular portion  602  can comprise an external diameter  702  that is sized to fit inside the pump shaft packing box  950 , and an internal diameter  704  that is sized to receive a pump shaft  850 . That is, for example, the tubular portion  602  can be configured to fit over the pump shaft  850 , and to fit inside (e.g., and fill) the pump shaft packing box  950 , such as in a slip-fit arrangement. In this way, for example, packing material may not be needed. 
     The example device  600  can comprise a flange  608  that is disposed at the proximal end  606  of the tubular portion  602 . In this implementation, the flange can comprise two fastener couplers  610 , that are respectively configured to receive a fastener  852  (e.g., a compression fastener, such as  158  of  FIG. 1 ). Further, the example device  600  can comprise a first gasket channel  612  that is configured to receive a gasket. The first gasket channel  612  can be disposed around the external surface  614  of tubular portion  602 , proximate to the distal end  604 . Additionally, the example device  600  can comprise a second gasket channel  616  that is configured to receive a gasket. The second gasket channel  616  can be disposed around the external surface  614  of tubular portion  602  proximate to the proximal end  606 . The example device  600  can also comprise a third gasket channel  706  that is configured to receive a gasket. The third gasket channel  706  can be disposed around the internal surface  618  of tubular portion  602 , between the first gasket channel  612  and the second gasket channel  616 . 
     In one implementation, the example device  600  can comprise a fourth gasket channel  620  that is configured to receive a gasket. The fourth gasket channel  620  can be disposed around the internal surface  618  of tubular portion  602 , proximate to the distal end  604 . Further, in one implementation, the fourth gasket channel  620  can be disposed between the first gasket channel  612  and the distal end  604  of the tubular portion  602 . In one implementation, a plurality of O-rings  902 ,  904 ,  906 ,  908  may be used as gaskets, to provide a slip-fit for the tubular portion on the pump shaft  850  in the pump shaft packing box  950 . In this implementation, the plurality of O-rings can comprise a first O-ring  902  disposed in the first gasket channel  612 ; a second O-ring  904  disposed in the second gasket channel  616 ; and a third O-ring  906  disposed in the third gasket channel  706 . Additionally, a fourth O-ring  908  can be disposed in the fourth gasket channel  620 . 
     As an example, as illustrated in  FIGS. 9-11 , the plurality of O-rings  902 ,  904 ,  906 ,  908  disposed in their respective gasket channels  612 ,  616 ,  706 ,  620 , can not only facilitate the slip-fit of the tubular portion  602  on the shaft  850  in the packing box  950 , but can also mitigate leakage of fluid. For example, gaskets  906  and  908  may facilitate containment of lubricant  1050  between the shaft  850  and the inner surface  618  of the tubular portion  602  (e.g., the bearing surface); and may also mitigate leakage of pumped fluid along the inner surface  618  of the tubular portion  602  toward the proximal end  606 . As another example, the gaskets  902  and  904  may facilitate containment of lubricant  1050  between the external surface  614  of the tubular portion  602  and the wall of the pump shaft packing box; and may further mitigate leakage of pumped fluid along the external surface  614  of the tubular portion  602  toward the proximal end  606 . As another example, the proximal gasket  906  can provide a secondary containment of liquid from the pumping chamber (e.g.,  154  of  FIG. 1 ) in the event that the distal gasket  908  were to fail. 
     The example device  600  can comprise a lubrication channel  622  that is configured to operably receive lubricant. In this implementation, the lubrication channel  622  can be disposed around the external surface  614  of the tubular portion  602 , between the first gasket channel  612  and the second gasket channel  616 . Further, the example device  600  can comprise a lubrication port  624  that is configured to operably transport lubricant  1050  between the lubrication channel  622  and the interior  618  of the tubular portion  602 . In this implementation, the lubrication port  624  can be disposed through a wall  702  of the tubular portion  602 , between the lubrication channel  622  and the interior  618  of the tubular portion  602 . In this way, for example, an external lubrication supply can be fluidly provided to the lubrication channel  622 , which, in turn, fluidly provides the lubricant  1050  to the interior  618  of the tubular portion  602 , by way of the lubrication port  624 . The lubricant  1050 , for example, can be used to operably lubricate a bearing surface between the interior  618  of the tubular portion  602  and the pump shaft  850 ; and may also operably provide lubrication for the dynamic seals between the inner gaskets  906 ,  908  and the rotating pump shaft  850 . 
     In one implementation, the example device  600  can comprise a seal removal component  626  that is disposed on the flange  608 . The seal removal component  626  can be configured to facilitate removal of the device  600  from the pump shaft packing box  950 . For example, the seal removal component  626  can comprise an access opening that allows a pulling tool to engage with the flange  608 , to pull the example device  600  from the pump shaft packing box  950 . As another example, the seal removal component  626  can comprise a threaded portion to further facilitate removal of the example device  600 . For example, the access opening of the seal removal component  626  may comprise internal threads that allows for engagement with an external threaded component. In on example, jack screws may be threaded into the seal removal component  626  to facilitate removal of the example device  600 . As another example, a pulling tool can be coupled with the jack screws to provide for easy removal of the example device  600 . 
     In one aspect, a pump can be devised that provides for improved sealing of the pump shaft of the pump, and ease of maintenance of the pump seal. In this aspect, in one implementation, as illustrated in  FIGS. 1-5 , the pump  50  can comprise a pump shaft  152  that rotates. For example, the rotation can be provided by a motor that is coupled to the shaft by way of a pump motor coupler  162 . Further, the pump  50  can comprise a pump rotor that is disposed in a pump chamber  154 . The pump rotor  164  can be operably coupled with the pump shaft  152 , and can be configured to move fluid as a result of the rotation of the shaft  152 . The pump  50  can also comprise a shaft casing  150  that is disposed around the pump shaft  152  to hold fluid seal system  100 . 
     In this aspect, in one implementation, the pump  50  can comprise a fluid seal component  100  that is disposed between the pump shaft  152  and the shaft casing  150  to mitigate fluid leakage from the pump chamber  154 . The fluid seal component  100  can comprise a one-piece, combination packing gland and bushing component  102  that comprises a proximal end  104  proximate the pump motor coupler  162 , and a distal end  106  distal from the motor coupler  162 . The packing gland and bushing component  102  can comprise a packing gland portion  108  at the proximal end  104 . The gland portion  108  can comprise two fastener couplers  302 , that are respectively configured to receive a compression fastener  158  to facilitate compression of packing material  112 . 
     The packing gland and bushing component  102  can also comprise a bushing portion  110  disposed at the distal end  106  that provides a bearing surface  114  for the rotating shaft  152 . Further, the packing gland and bushing component  102  can comprise an inner gasket channel  116  that is disposed at a proximal end  104  of the interior  308  of the bushing portion  110 . Additionally, the packing gland and bushing component  102  can comprise an inner gasket  208  that is disposed in the inner gasket channel  116  between the inside  308  of the bushing portion  110  and the rotating shaft  152 . The inner gasket  208  can be configured to mitigate leakage of a lubricant from the inside of the bushing portion  110 . In one implementation, the pump  50  can comprise packing material  112  that is disposed in the shaft casing  150  at the distal end  106  of the packing gland and bushing component  102 . The packing material  112  can be subjected to compression force provided by the packing gland and bushing component  102 , to mitigate leakage of fluid from the pumping chamber  154 . 
     In one implementation, in this aspect, the packing gland and bushing component  102  can comprise an outer gasket channel  118  that is disposed proximate the proximal end  104  of the bushing portion  110 . The outer gasket channel  118  can be used to hold a gasket between the outside of the bushing portion  204  and a wall of the shaft casing  156 . As an example, the outer gasket channel  118  can hold an outer gasket  210 , such as an O-ring. 
     Further, the packing gland and bushing component  102  can comprise a lubricant channel  202  that is configured to operably receive bushing lubricant  160 . In this implementation, the lubricant channel  202  can be disposed around the external surface  204  of the bushing portion  110  at a location that is distally from the inner gasket channel  116 . Further, a lubricant port  206  can be configure to operably transport lubricant  160  from the lubricant channel  202  to the interior  308  of the bushing portion  110 , such as to the bearing surface  114 . The lubricant port  206  can be disposed through a wall  306  of the bushing portion  110  between the lubricant channel  202  and the interior  308  of the bushing portion  110 . 
     In one implementation, in this aspect, the example 50 can comprise a threaded packing gland and bushing removal component  304  that is disposed on the packing gland portion  108 . The threaded packing gland and bushing removal component  304  can be configured to facilitate removal of the packing gland and bushing component removal component from the pump shaft casing. For example, a pulling tool or jack screws, may be coupled with the packing gland and bushing removal component  304  for easy removal of the packing gland and bushing component  102  from the shaft casing  150 . 
     Moreover, the word “exemplary” is used herein to mean serving as an example, instance or illustration. Any aspect or design described herein as “exemplary” is not necessarily to be construed as advantageous over other aspects or designs. Rather, use of the word exemplary is intended to present concepts in a concrete fashion. As used in this application, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.” That is, unless specified otherwise, or clear from context, “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then “X employs A or B” is satisfied under any of the foregoing instances. Further, At least one of A and B and/or the like generally means A or B or both A and B. In addition, the articles “a” and “an” as used in this application and the appended claims may generally be construed to mean “one or more” unless specified otherwise or clear from context to be directed to a singular form. 
     Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims. 
     Also, although the disclosure has been shown and described with respect to one or more implementations, equivalent alterations and modifications will occur to others skilled in the art based upon a reading and understanding of this specification and the annexed drawings. The disclosure includes all such modifications and alterations and is limited only by the scope of the following claims. In particular regard to the various functions performed by the above described components (e.g., elements, resources, etc.), the terms used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary implementations of the disclosure. In addition, while a particular feature of the disclosure may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms “includes,” “having,” “has,” “with,” or variants thereof are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term “comprising.” 
     The implementations have been described, hereinabove. It will be apparent to those skilled in the art that the above methods and apparatuses may incorporate changes and modifications without departing from the general scope of this invention. It is intended to include all such modifications and alterations in so far as they come within the scope of the appended claims or the equivalents thereof.