Patent Publication Number: US-11019967-B2

Title: Central vacuum system and inlet valves therefor

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation application of U.S. patent application Ser. No. 15/675,228, filed Aug. 11, 2017, which is a continuation-in-part of U.S. patent application Ser. No. 14/570,159, filed Dec. 15, 2014, now U.S. Pat. No. 9,782,047, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/923,949, filed Jan. 6, 2014; the disclosures of which are entirely incorporated herein by reference. 
     U.S. patent application Ser. No. 15/675,228 also claims the benefit of U.S. Provisional Patent Application Ser. No. 62/457,558, filed Feb. 10, 2017; the disclosure of which is entirely incorporated herein by reference. 
    
    
     BACKGROUND 
     Technical Field 
     The invention relates to a central vacuum cleaning system, including inlet valves therefor which can be mounted on a structure in a variety of positions and connected to the inlet end of a vacuum conduit for holding the handle of a vacuum cleaning hose which is slidably mounted within the conduit when the hose is in a retracted position, and which seals the outlet end of a debris pickup nozzle handle and the vacuum conduit enabling the inlet valve to be of an open non-sealed construction and used in multiple inlet valve cleaning systems, and which provides a locking mechanism for releasably securing the hose in an extended condition from the conduit. 
     Background Information 
     Central vacuum systems for home and commercial use have been used for many years, examples of which are shown in U.S. Pat. Nos. 2,943,698 and 3,173,164. These systems generally are comprised of a main vacuum source which is usually mounted in the basement or other locations in the structure or closely adjacent thereto. The vacuum source is connected to various dedicated inlet valves in the structure by conduits or tubing. These inlet valves, also referred to valve boxes in the industry, are mounted in a wall, inside of a cabinet or in and on other structures by various types of flanges, brackets etc. Some examples are shown in U.S. Pat. Nos. 2,953,806, 3,520,725, 4,336,427, 6,459,056, and 7,624,472. 
     More recently, many of these vacuum systems use a hose that is slidably moveable and contained within the vacuum conduit and expandable therefrom, so that the hose is pulled from the conduit for cleaning an area and then retracted back into the vacuum conduit for storage after use. Some examples of such systems are shown in U.S. Pat. Nos. 2,953,806, 7,010,829, and 8,001,650. These systems have a handle or debris pickup nozzle which is attached to the end of the hose and which is retained in or stored closely adjacent to the inlet valve or on other types of supporting brackets or cradles when not in use, such as shown in the above-mentioned patents. Also, some of these prior art systems and inlet valves are provided with some type of locking mechanism to secure the hose in an extended position such as shown by the manually actuated locking mechanism of U.S. Pat. No. 7,010,829 or an external locking loop as shown in U.S. Pat. No. 8,590,098. 
     Heretofore, these inlet valves or valve boxes are sealed from the ambient atmosphere by a relatively air-tight box and closure door to seal the vacuum from the surrounding atmosphere. This air-tight sealing arrangement for the stored nozzle enables the vacuum system to be maintained operational for other inlet valves located throughout the structure which are also connected to the same vacuum source by the rigid tubing or flexible conduits. This air-tight sealing arrangement is necessary to maintain the vacuum operational throughout the system, but requires a more complicated and expensive inlet valve box than desirable for many applications and installations. 
     Thus, it is desirable to provide an inlet valve which can be open to the surrounding atmosphere in which the debris pickup nozzle is stored when not in use, which enables the other inlet valves of the vacuum cleaning system throughout the structure to be operational, and which will eliminate any noise or other problems that are associated with such prior art sealed inlet boxes. 
     Central vacuum cleaning systems also are becoming popular in recreational vehicles and camping trailers. However, one problem is that space is very limited and it is difficult to install the rigid type of vacuum supply conduits as used in most residential and commercial buildings. Furthermore, storage space for the cleaning hose and nozzle handle attached to the inlet end thereof is at a premium in these RVs. Also it is difficult to find an area within the RV to secure the handle when not in use as well as sealing the inlet end of the conduit when used in multiple vacuum inlets within the RV. Although prior art pneumatic systems for structures and RVs with an associated locking mechanism perform satisfactory, they require numerous components and are difficult to mount in a variety of locations and on available structures. 
     SUMMARY 
     In one aspect, the present disclosure may provide An inlet valve for mounting on a structure and connected to a conduit of a vacuum cleaning system comprising: a body formed with a bore with inner and outer open ends, said inner open end adapted to be connected with the conduit of the central vacuum cleaning system; a length of flexible hose adapted to be slidably mounted within the conduit and expandable from and retractable within the conduit and moveable through the bore of the body and through the outer open end, said hose having a nozzle end and a distal end; a handle mounted on the nozzle end of the hose, said handle having an open end for picking up debris from an adjacent area; a first seal mounted in the body and engageable with the handle when the hose is in a retracted position in the conduit and the handle is in a stored position in the body to provide a substantially air-tight seal between the handle and vacuum conduit; and a second seal for sealing the open end of the handle when the handle is in the stored position in the body, said first and second seals sealing the conduit and open end of the handle from the ambient atmosphere at the inlet valve. 
     In another aspect, the present disclosure may provide in combination, a length of flexible hose having a nozzle end and a distal end adapted to be slidably received in a conduit of a central vacuum cleaning system; and an inlet valve box for storing a handle mounted on the nozzle end of the hose when the handle is in a stored position within the inlet valve box; said valve box including: a housing having a front opening through which the hose is extendable and retractable, said housing having a lower portion including a plurality of walls forming an interior chamber open to the ambient atmosphere; a first seal mounted within the lower portion of the housing for sealing engagement with an open end of the handle when the handle is in a stored position in the interior chamber; a second seal mounted in an upper portion of the housing for sealing engagement with the handle when the handle is in the stored position; and said first and second seals sealing the open end of the handle and the conduit from the ambient atmosphere at the inlet valve box. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       Various embodiments of the invention are set forth in the following description, are shown in the drawings and are particularly and distinctly pointed out and set forth in the appended claims. One of ordinary skill in the art will appreciate that in some examples one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of another element may be implemented as an external component and vice versa. Furthermore, elements may not be drawn to scale. 
         FIG. 1  is a diagrammatic view showing a structure having a central vacuum source in the lower level thereof connected to various inlet valves of the present disclosure located within the structure. 
         FIG. 1A  is a diagrammatic view showing the central vacuum cleaning system and one of the inlet valves of the present disclosure comprised principally of a locking collar mounted within a recreational vehicle. 
         FIG. 2  is a top perspective view showing one of the inlet valves of the present disclosure which is a unique locking collar mounted on a supporting structure with the cleaning hose in a fully retracted position within a flexible outer conduit as shown in  FIG. 1A , and with an end sealing cap mounted on the open end of the nozzle handle. 
         FIG. 2A  is a top perspective view similar to  FIG. 2  with portions broken away showing the locking collar of the present disclosure without the sealing end cap. 
         FIG. 3  is a top perspective view similar to  FIG. 2  showing the nozzle handle removed from the locking collar and the internal hose in a partially extended position. 
         FIG. 4A  is an exploded perspective view showing the lock housing, locking mechanism and hose stop components of the locking collar. 
         FIG. 4B  is an enlarged exploded perspective view showing the locking collar mounting clamps and collar support bracket. 
         FIG. 4C  is a fragmentary exploded view of the nozzle handle and internal hose in combination with the sealing rings and flared end component of the locking collar. 
         FIG. 5  is a front elevational view of the locking collar and nozzle handle with a rigid outer conduit as shown in  FIG. 1 , with the locking finger in the unlocked position. 
         FIG. 6  is a left side elevational view of the locking collar as shown in  FIG. 5 . 
         FIG. 7  is a rear elevational view of the mounting bracket attached to the locking collar. 
         FIG. 8  is a top plan view showing the locking collar in three adjusted positions on the mounting bracket. 
         FIG. 9  is a sectional view taken along line  9 - 9 ,  FIG. 5 . 
         FIG. 10  is a view similar to  FIG. 5  showing the locking collar and mounting clamps rotated 45° in a counterclockwise direction from its vertical position. 
         FIG. 11  is a view similar to  FIG. 10  showing the locking collar and mounting clamps rotated 45° in the clockwise direction from the vertical position of  FIG. 5 . 
         FIG. 12  is an enlarged sectional view taken along line  12 - 12 ,  FIG. 8  showing the cleaning nozzle handle in a sealed and stored position in the locking collar. 
         FIG. 13  is an enlarged view of the encircled portion in  FIG. 12 . 
         FIG. 14  is a view similar to  FIG. 12  showing the locking finger in locking engagement with the retractable hose when the hose is in a partially extended position. 
         FIG. 15  is an enlarged fragmentary view of the encircled portion of  FIG. 12  showing the locking finger engaged with the cleaning hose. 
         FIG. 16  is a view similar to  FIG. 14  with the locking finger in its unlocked, retracted position. 
         FIG. 17  is a greatly enlarged fragmentary view of the encircled portion of  FIG. 16 . 
         FIG. 18  is a diagrammatic view similar to  FIG. 1  showing other types of inlet valve boxes mounted within a structure 
         FIG. 19  is an enlarged view of the encircled portion of  FIG. 18  with portions broken away showing another type of inlet valve of the present disclosure mounted in a wall opening with the closure door in open position. 
         FIG. 20  is a front elevational view looking in the direction of arrows  20 - 20 ,  FIG. 19 . 
         FIG. 20A  is an exploded side elevational view showing many of the components in the lower portion of the valve box of  FIGS. 19 and 20 . 
         FIG. 20B  is an exploded side elevational view of many of the components in the upper portion of the valve box of  FIG. 20-20A  and the distal end of the vacuum hose. 
         FIG. 21A  is an exploded front elevational view of many of the components in the lower portion of the valve box as shown in  FIG. 20A . 
         FIG. 21B  is a front elevational view of the closure door and door mounting flange of the valve box as shown in  FIG. 20A . 
         FIG. 21C  is an exploded elevational view of the upper components of the valve box and distal end of the vacuum hose as shown in  FIG. 20B . 
         FIG. 22A  is a sectional view taken on line  22 A- 22 A,  FIG. 20 . 
         FIG. 22B  is a sectional view similar to  FIG. 22A  showing the valve box mounted in a structure having a thicker outer wall than that shown in  FIG. 22A . 
         FIG. 23  is a vertical sectional front view of the valve box similar to  FIG. 22A . 
         FIG. 24  is a side sectional view similar to  FIG. 22B  showing the nozzle handle removed from the valve box and the hose in a fully extended position. 
         FIG. 25  is an enlarged fragmentary sectional view taken on line  25 - 25 ,  FIG. 24  of the distal end of the hose when the hose is in a fully extended position. 
         FIG. 26  is a sectional view taken on line  26 - 26 ,  FIG. 25 . 
         FIG. 27  is a side elevational view similar to  FIG. 22A  showing a modified valve box and seal assembly. 
     
    
    
     Similar numbers refer to similar parts throughout the drawings. 
     DETAILED DESCRIPTION 
     One example of a central vacuum cleaning system in which an inlet valve of the present disclosure is located is indicated generally at  1 , and is shown in  FIG. 1 . A central vacuum source  5  is located within a usual structure  3  such as in a lower level  7 . However, vacuum source  5  could be located at other locations in the structure or outside closely adjacent thereto. A plurality of vacuum source tubes or conduits  9  extend from vacuum source  5  to various locations or rooms within structure  3 . The number of conduits will depend upon the size of the house, number of rooms, size of vacuum source  5 , and other factors. These vacuum supply conduits are usually formed of rigid plastic and terminate at various inlet valves in the structure, three of which are shown in  FIG. 1 . 
     One of the vacuum supply conduits terminates at a usual air-tight wall valve  11 , whereas another supply conduit terminates at a similar valve in a wall storage cabinet  13 , with another supply conduit terminating at a first embodiment of the inlet valve of the present disclosure which is indicated generally at  25  and shown mounted under a counter  12 . It is also readily understood that conduits  9  could extend into various locations within the structure and attached to other types of inlet valves without affecting the concept of the invention. 
       FIG. 1A  illustrates the first inlet valve  25  of the present disclosure hereinafter referred to as a locking collar, installed in a recreational vehicle (RV)  14 . Locking collar  25  is well suited for use in such a confined area such as an RV. In this type of vacuum system, a usual vacuum power supply  15  is located in a storage area  17  with inlet valve or collar  25  being located in a cabinet  19  or other easily accessible location within the RV. Preferably in an RV the vacuum supply conduit will be a flexible hose  23  in place of rigid conduits  9  of  FIG. 1 , enabling it to be installed to conform to the available space and contours of an RV when space is at a premium. Although  FIG. 1A  shows only a single inlet valve or collar  25 , it is readily understood that the RV can have multiple inlet valves throughout the vehicle all connected to vacuum source  15 . 
     As shown in  FIGS. 2, 2A and 3 , the vacuum supply conduit is shown as a flexible hose  23  and in  FIGS. 5-17  it is shown as a rigid conduit  9  for illustrative purposes. A section of a flexible hose  16  will be contained within each of the conduits  9  and  23  and will have a nozzle handle  20  attached to the outer end of hose  23  for grasping by an operator for cleaning an adjacent area. Collar  25  of the present disclosure and the main components thereof are shown in detail in  FIGS. 4A, 4B, and 4C . Collar  25  preferably is molded of plastic, although it could be formed of metal without affecting the concept of the invention. Collar  25  is formed with a through bore or passage  29  which terminates in an open inner end  31  and an open outer end  33  ( FIGS. 12 and 14 ). Collar  25  includes a main body  35  which has a cylindrical end section  37  and a larger diameter cylindrical central section  39  which terminates in an annular upper ring  41  connected to central section  39  by an annular shoulder  43 . 
     An annular end section or collar, indicated generally at  45  ( FIGS. 4C and 12 ), terminates in an inner right angle shoulder  47  which is slidably received within and against the inside surface  49  of annular ring  41  and sets upon annular shoulder  43  of central section  39 . Shoulder  43  is formed at the junction of the upper portion of annular ring  41  and the top end of central section  39 . End collar  45  terminates in an outwardly flared end flange  53  which guides the handle  20  into the collar body when the hose is moving toward a stored position. Flange  53  forms the open outer end  33  of the locking collar and has a smooth inner cylindrical wall  54  which forms a through bore of end collar  45 . 
     An O-ring  55 , formed of a rubber or some type of resilient material, is located between step shoulder  47  of end collar  45  and annular shoulder  43  of central section  39 . Ring  55  has an inner diameter generally complementary to the inner diameter of end collar  45  and provides a frictional sliding fit with handle  20  to assist in retaining handle  20  within body  35  when in its stored position. A sealing ring  57  formed of a resilient material such as rubber, felt or a foam material, is seated upon an annular shoulder  59  formed between central section  39  and cylindrical end section  37 . Ring  57  provides an air seal with the annular bottom edge  51  of handle  20  when the handle is in its stored position as shown in  FIG. 12 . 
     An annular hose stop, indicated generally at  61  ( FIGS. 4A, 12 and 17 ), terminates in an inwardly curved upper shoulder  63  and a main cylindrical body  65  which terminates in a larger diameter section  66  and a smaller internal diameter  64 . Hose stop  61 , as shown particularly in  FIG. 12 , is slidably received in the internal diameter of cylindrical end section  37  with the stepped upper shoulder  63  engaging shoulder  59  to properly position stop  61  within the interior of end section  37 . Hose stop  61  prevents the distal end of the hose from being pulled out of locking collar  25  if the hose is not needed for use in the other inlet valves throughout the dwelling. Ring  61  can easily be eliminated from locking collar  25  permitting easy removal of the hose therefrom without affecting the concept of the present disclosure. 
     In accordance with another feature of the invention, a locking mechanism indicated generally at  67 , is mounted on main collar body  35  ( FIG. 4A ). Locking mechanism  67  includes a lock housing  69  which is mounted on the exterior of body  35  by a pair of fasteners  71  which extend through a pair of holes  72  formed in top wall  78  and threadably engage a pair of spaced posts  73  formed integrally with annular ring  41 , and by another fastener  75  which extends through a hole  76  formed in a central post  70  of lock housing  69 . Fastener  75  is engaged within an opening  77  formed in the lower end of a stud  80  having a pair of spaced members  79  formed integrally with and projecting outwardly on stud  80  of central section  39 . 
     Locking mechanism  67  furthermore includes a pair of spaced flanges  81  which are formed integrally with and extend outwardly from central section  39  of body  35 . Each flange  81  is formed with a hole  83  which snap fittedly receives a pair of bosses  85  which are formed on and extend outwardly from the ends of a locking member or finger indicated generally at  87 . Locking member  87  terminates in a laterally extending locking edge  89  and an opposite finger tab  91 . 
     Lock housing  69  is formed with a pair of cut-outs  93  in side walls  95  thereof which receive annular ring  41  therein when mounted on body  35  as best shown in  FIG. 6 . Rear wall  97  of lock housing  69  is formed with a pair of cut-outs  98  adjacent central post  70  through which spaced portions  96  of locking finger  87  extend when lock housing  69  is secured to main body  35  enabling locking finger  87  and in particular finger tab  91  thereof, to extend externally of lock housing  69  as shown in  FIGS. 5 and 6 . 
     In further accordance with the invention, an electric switch  100  is mounted within lock housing  69  and is adapted to be connected to vacuum sources  5  and  15  by electrical conductors or wires  101 . Switch  100  includes an actuation toggle button  102  which extends through an opening  103  formed in a top wall  78  of housing  69 . 
     Locking finger  87  is spring biased by a spring  104  toward a locking position when it is engaged with hose  16  as shown in  FIG. 14  and toward an unlocked retracted position as shown in  FIG. 16 . Spring  104  extends between a pin  105  which is mounted within a pair of notches  106  formed at the outer ends of studs  79  ( FIGS. 4A and 12 ) and at the opposite end to a pin  107  slidably received through a pair of openings  94  formed in a pair of lugs  86  formed on and extending outwardly on locking finger  87  generally adjacent locking edge  89 . Spring  104  when in a first position biases locking edge  89  toward locking engagement with hose  16  as shown in  FIGS. 14 and 15  and biases the locking finger into an unlocked disengaged position as shown in  FIG. 16 . 
     In accordance with another feature of the invention, locking collar  25  includes a mounting bracket indicated generally at  108  ( FIGS. 4B and 7 ) and a clamp mechanism indicated generally at  109 , for adjustably mounting body  35  onto bracket  108 . Mounting bracket  108  includes a flat plate  110  formed with a pair of right angled side flanges  111  and a top ledge  112  which extends outwardly beyond end flanges  111 . Four mounting holes  113  are formed generally adjacent the four corners of plate  110  for receiving fasteners (not shown) for securing bracket  108  to a supporting structure. Holes  113  can be counter-bored as shown in  FIG. 4B  so that the fastener heads are generally flush with the surface of plate  110  when bracket  108  is secured to a supporting structure. 
     A plurality of holes  115 , six are shown in the drawings, are formed through plate  110  for adjustably mounting a pair of clamp members  116  and  117  thereon as discussed below which form clamp mechanism  109 . Clamp members  116  and  117  have a generally rectangular configuration with bottom clamp  116  being formed with a pair of holes  119  for receiving a pair of fasteners  120  which project through a selected pair of holes  115  formed in plate  110  and secured thereon by a pair of nuts  121  as shown in  FIGS. 4B and 7 . Lower clamp body  116  is formed with an arcuate projection  123  forming an arcuate slot or channel  124  with the front surface of clamp  116 . 
     Upper clamp  117  is formed with a pair of holes  125  for receiving a pair of bolts  126  therethrough which extend through aligned holes  127  formed in lower clamp  116  for securing engagement with a pair of nuts  128  for clamping clamp members  116  and  117  together. Upper clamp  117  is formed with an arcuate projection  129  which forms an arcuate slot or channel  130  between projection  129  and the body of upper clamp  117 . When clamp bodies  116  and  117  are clamped together by fasteners  126 , arcuate channels  124  and  130  align and receive annular ring  41  therein, as shown in  FIG. 6 , to adjustably mount main body  35  on clamp mechanism  109  and subsequently on mounting bracket  108 . 
     Handle  20  includes a cylindrical end section  22  which is attached to the end of hose  16  by a threaded engagement, adhesive, or other type of securement means to firmly attach handle  20  to the end of hose  16 . Handle  20  further will include a reduced diameter nozzle end  24  terminating in an open end  26  through which dirt and other debris is collected by the vacuum imparted onto hose  16  during a cleaning operation. The opposite end of hose  16  will have an end seal  131  ( FIGS. 4C and 16 ) secured thereto by a threaded engagement, adhesive, or other securement means. 
     Hose end seal  131  is an annular ring formed having an internal bore generally complementary to the internal bore of hose  16  so as not to impede the vacuum flow. As best shown in  FIGS. 16 and 17 , the outer diameter of hose end seal  131  will be slightly smaller but complementary to the diameter of hose stop  61 , but larger than the internal diameter of cylindrical body  65  of hose stop  61 . This ensures that hose end seal  131  will not pull through locking collar  25  as shown in  FIG. 16 . Thus, as a user pulls hose  16  through the conduit, seal  131  will limit the outward movement of the hose by engagement of end seal  131  with the smaller diameter of hose stop  61 . 
       FIGS. 1A, 2, 2A, 3 and 4C  show collar  25  attached to a flexible conduit  23 , and  FIGS. 5-17  show collar  25  attached to a rigid conduit  9  for illustration purposes only. Either type of conduit will work equally well with collar  25 . 
     As shown in  FIG. 12 , rigid conduit  9  is connected to locking collar  25 , and in particular to main body  35  by slidingly inserting it into the end of cylindrical end section  37  where it abuts against the bottom edge of hose stop  61  pressing curved shoulder  63  thereof against annular shoulder  59 . Hose stop  61  preferably is glued in position. Conduit  9  will be secured in end section  37  by an adhesive, threaded engagement, or other type of attachment well-known in the central vacuum cleaning art. 
     Flexible conduit  23  can be secured to locking collar  25  by a short section of rigid tube  133  and a coupler  134  preferably having a bell-shaped end  135  for receiving the end of hose  23  therein. It will also be secured by a threaded engagement, adhesive, or other type of attachment means as with rigid conduit  9 . The inside diameter of conduits  9  and  23  is generally complementary to the outer diameter of hose end seal  131  in order to provide a sliding fit therebetween, as well as providing an air seal therebetween ensuring that the majority of the vacuum source is transmitted through the conduit and subsequently through the interior of hose  16  to achieve maximum dirt and debris pickup through the open end of handle  20  yet enabling hose  16  and end seal  131  to slide easily into and out of conduits  9  and  23 . 
     Locking collar  25  is installed easily in a structure or RV by first attaching mounting bracket  108  to a support structure by fasteners  114  which can be screws, bolts, rivets, or other type of fastener depending upon the nature of the support structure to which mounting bracket  108  is attached. Preferably, top flange  112  is placed against an edge of the supporting structure to align the mounting bracket thereon and enable it to be placed in a variety of locations within a structure. Bracket flange  112  can be placed horizontally on a structure as shown in  FIG. 2A  or can extend vertically along a structure edge (not shown) or in various other positions for subsequent attachment of collar  25  thereon. 
     Lower clamp body  116  is attached to bracket plate  110  by inserting fasteners  120  through a pair of selected holes  115  and secured thereon by nuts  121 . Main body  35  is mounted on lower bracket  116  by inserting the lower end of annular ring  41  within arcuate groove  124 . Top body clamp  117  is placed in position with the top portion of ring  41  being seated within arcuate groove  130 . Upper clamp body  117  is then secured on lower clamp body  116  by fasteners  126  and nuts  128 . Initially, the clamping pressure exerted between clamp bodies  116  and  117  will be sufficient to secure ring  41  therebetween, yet loose enough to permit body  35  to be rotated with respect to mounting bracket  108  between various angular positions as shown in  FIG. 8 . After rotation of body  35  to the desired position, bolts  126  are then tightened to prevent further rotation of ring  41  within aligned channels  124  and  130 . This feature enables body  35  to be adjusted to various angular positions on a supporting structure enabling it to be mounted at various locations and on various structures within a supporting structure, especially within an RV where spaced is limited. This adjustability will provide the best access for a user to pull handle  20  and attached hose  16  through collar  25  for a cleaning operation. 
     In accordance with another feature of the invention, which is especially helpful when mounting collar  25  in the narrow confines of an RV, is the ability to place collar  25  at various angular positions on mounting bracket  108  as shown particular in  FIGS. 7, 10, and 11 . This is achieved by selecting an appropriate pair of holes  115  through which mounting bolts  120  will extend when mounting the clamp mechanism onto mounting bracket  108 . As shown in  FIG. 7 , locking collar  25  is in a true vertical position and alignment with respect to the mounting plate as shown in  FIGS. 5 and 6 . However, it can easily be mounted in a variety of angular positions with respect to the mounting plate as shown in  FIGS. 10 and 11 , by merely selecting the appropriate holes on mounting bracket  108  for receiving bolts  120 . 
     Another feature of clamp mechanism  109  is the ability to mount clamp bodies  116  and  117  directly onto a supporting structure by a pair of fasteners, such as screws, which will replace bolts  120  and extend directly through holes  119  into the supporting structure eliminating the need for bracket  108 . Again, after securing bottom clamp body  116  to a supporting structure, top clamp body  117  is then secured thereto by bolts  126 . It is readily apparent that bottom clamp member  116  can be mounted at various angles on a supporting structure, whether it extends vertically, horizontally, or on the side, top or bottom of a structure such as a cabinet or wall, after which the angular position of the valve body can be adjusted thereon as shown in  FIG. 8 . 
     When a user wishes to use handle  20  for cleaning an area adjacent collar  25 , he or she will manually pull outwardly on handle  20  extending hose  16  from within its stored position within conduits  9  or  23  to a desired length. Locking finger  87  will pivot freely in the direction of arrow A of  FIG. 14  enabling hose  16  to slide past locking end  89  of finger  87  until the desired amount of hose is pulled from within the conduit. Locking finger  87  will pivot automatically in the direction of arrow B by the bias of spring  104  whereupon locking end  89  will automatically become engaged in a locking relationship within one of the valleys  90  formed between adjacent peaks  92  of hose  16 . The operator can easily extend the hose further from within the conduit by merely pulling outwardly on the handle whereupon the lock finger will pivot out of locking engagement with hose  16  until the desired length is reached. Upon stopping this outward movement locking finger  87  will immediately assume another locked position within another valley  90 . To unlock hose  16 , the operator merely pivots locking finger  87  out of its locked position by manually moving finger tab  91  in the direction of arrow A of  FIG. 14  to the unlocked position of  FIG. 16 . In this position, locking end  89  is removed from within its locked position with the hose. Finger  87  will remain in the unlocked position of  FIG. 16  after being manually moved to this position by the biasing action of spring  104 . 
     The hose will be automatically withdrawn into the interior of the conduit after unlocking finger  87  by the force of the vacuum or by a coil spring within the hose, which construction and action is well known in the vacuum cleaning art. Hose  16  can be a rigid non-expandable hose if desired, which also is easily retracted within the conduit by the vacuum force and by manually pushing the hose back into the conduit when a cleaning operation is completed. In a typical installation, hose  16  may have a length of approximately 7 feet and extendable to a length of approximately 30 feet. Locking collar  25  is easily adaptable for use with various types of cleaning hoses whether they be the expandable type with or without internal springs, or a more rigid non-expandable hose. 
     When collar  25  is used in a vacuum cleaning system having multiple inlets such as shown in  FIG. 1 , a sealing end cap  137  ( FIG. 2 ) is provided for manually placing over the open end  26  of handle  20  to seal the open end. End cap  137  in combination with sealing ring  57  as shown in  FIG. 12  sufficiently seals the vacuum in conduits  9  or  23  and the open end of the handle. This double seal effectively seals the vacuum within the conduit and open end of the handle, enabling the vacuum supply to maintain the vacuum on the other inlets as shown in  FIG. 1  and eliminates collar  25  from being enclosed in an air-tight box as in prior art inlet valves. End cap  137  preferably will have a tether (not shown) either connected to mounting plate  108 , handle  20  or collar  25 . When collar  25  is used in a single inlet dedicated vacuum cleaning system as shown in  FIG. 1A , no end cap  137  will be required. 
     If desired, end cap  137  could be replaced with a type of molded holster (not shown) which will hold the handle in a stored position and seal the handle end simultaneously within the concept of the present disclosure. 
     In summary, the vacuum cleaning system and collar of the present disclosure enables the system to be installed in a usual dwelling with multiple vacuum inlets and particularly in an RV where space is at a premium. The collar can be mounted at various positions on a variety of supporting structures by a simple L-shaped mounting bracket  108  or directly by clamp members  116  and  117  which rotatably mount the collar body thereon enabling it to be rotated to a variety of positions. This adjustability of mounting the collar on the bracket in a variety of angular positions, as well as the rotational mounting of the collar body on the supporting clamp brackets enables the collar to match the available space and enables the user to easily grasp the handle therefrom when performing a cleaning operation. 
     The use of internal sealing ring  57 , together with the sealing provided by end cap  137 , enables the collar to be used in a multiple inlet valve vacuum cleaning system and provide an inlet valve which is open to the ambient atmosphere avoiding the additional expense of providing an air-tight inlet valve. The incorporation of switch  100  in the locking mechanism housing provides a readily accessible means of turning the vacuum system ON and OFF. Likewise, ring  55  provides a retention mechanism to assist in retaining handle  20  within the collar as shown in  FIG. 12  in addition to assisting the vacuum seal therewith. Again, the rotational mounting of the collar body offers a wide degree of installation versatility while still securely holding the handle in a stored position, and the selective mounting of the clamp members on the bracket and the L-shaped configuration of the bracket and multiple mounting holes allows installation at various angular orientations and on various supporting structures, especially in an RV where space is at a premium. 
       FIG. 18  is another example of a central vacuum cleaning system in which another embodiment of the inlet valve of the present disclosure is incorporated, and which is indicated generally at  200 . Inlet valve  200  is shown mounted within structure  3  and connected to central vacuum source  5  by a conduit  9 . The vacuum system may contain other types of inlet valves such as indicated at  201 , located at other locations in the structure. Again, the number of conduits and inlet valves and types of inlet valves will depend upon the size of the structure, number of rooms, size of the vacuum source  5 , and other factors. 
     Inlet valve  200  is shown particularly in  FIGS. 18-26  attached to a wall stud  204  and accessible through an opening formed in an attached wall board  202 , such as drywall used in a usual home construction. Inlet valve  200  of this modified embodiment is hereafter referred to as a valve box to distinguish from locking collar  25  discussed above. Valve box  200  can be used in various types of constructions and other structure locations than that shown in  FIGS. 18 and 19  within the concept of the present disclosure. 
     Valve box  200  includes a main body or housing indicated generally at  212 , formed by a lower portion  213  and an upper portion  224 . Lower portion  213  ( FIGS. 20A and 21A ) is formed by a pair of side walls  215 , a rear wall  217 , a top wall  218  and a bottom wall  219 , which walls define an interior chamber  214 , a front or outer end opening  221  and an open top  223 . Lower portion  213  preferably will have a rectangular shape as shown in  FIG. 21A . 
     Upper portion  224  ( FIGS. 20B and 21C ), includes a box top  225  which is mounted on and encloses open top  223  of lower portion  213 . The upper edges of side walls  215  of lower portion  213  are formed with U-shaped channels  227  ( FIG. 20A ) which slidably receive therein complementary-shaped channels  229  formed along side walls  231  of a lower rectangular-shaped bottom portion  233  of box top  225  to mount upper portion  224  on lower portion  213 . This sliding engagement enables lower portion  213  and upper portion  224  of housing  212  to be produced independently, preferably of a molded plastic, and then assembled after the various internal components thereof which are described below, are mounted respectively in lower portion  213  and top portion  224 . 
     An enlarged opening  235  ( FIG. 22A ) is formed in bottom wall  219  of lower portion  213  of housing  212  and receives therein a generally rectangular portion  237  ( FIGS. 20A, 21A, and 22A ) of a bottom bracket indicated generally at  239 , which is secured therein by screws  238 . It is readily understood that portion  237  and complementary-shaped opening  235  can have other shapes such as round, oval-shaped, etc. Bracket  239  is formed with a pair of spaced vertically extending channels  241  ( FIG. 23 ) in which are mounted a pair of compression coil springs  243 . Springs  243  engage a horizontally extending pin  245  which extends through a diametric hole  247  formed in a ball  249 . Ball  249  is located in a central channel  251  formed in bottom bracket  239 . A downwardly extending ramp  240  ( FIGS. 20 and 22B ) is formed by a recessed area in top wall  242  which is formed with an upper flange  244  in which ball  249  is located. The purpose and function of bracket  239  and ball  249  are described further below. 
     Box top  225  ( FIGS. 20B, 21C and 25 ), in addition to having a lower rectangular portion  233 , includes a cylindrical intermediate portion  253  which is connected to an upper reduced diameter cylindrical top portion  255  by a horizontal annular portion  256  providing a bell-shaped configuration to box top  225 . Box top  225  is formed with a hollow interior  258  which terminates in a top opening  254 . Box top  225  preferably will be a one-piece molded plastic member as are portions  213  and  224  of housing  212 . The hollow interiors  214  and  258  of lower portion  213  and box top  225  provide a through bore for inlet valve  200  which terminates in inner open end  254  and outer open end  221  for the passage of a flexible hose  285  therethrough. 
     Within box top  225  is a cylindrical sleeve ( FIGS. 22A, 22B, 24 and 25 ) indicated generally at  257 , which provides another seal when the hose reaches its fully extended position as discussed further below. Sleeve  257  has a generally annular configuration formed by an annular wall  259  which has a cylindrical outer surface  260  and a cylindrical lower inner surface  260 A which terminates in an outwardly tapered upper inner annular surface  260 B which forms a top opening  262 A. A pair of diametrically opposed cylindrical lugs  263  extend outwardly from annular wall  259  ( FIGS. 25 and 26 ). Each lug  263  has a hollow bore  264  in which is contained a spring  265  retained therein by an end plug  266 . Each spring  265  biases a button  267  outwardly through a hole  268  formed through wall  259  and into the hollow bore  262  of cylindrical sleeve  257 . The function of buttons  267  is described further below. 
     Sleeve  257  is retained within interior  258  of box top  225  by a slip-fit engagement and by a two-piece hose stop ring indicated generally at  270  ( FIGS. 20B and 21C ). Ring  270  is clamped against the bottom of annular wall  259  of sleeve  257  by an annular O-ring support ring, indicated generally at  271  ( FIG. 25 ). Ring  271  is seated upon and secured within box top  225  by a one-piece horseshoe-shaped retaining bracket  273 . Bracket  273  is secured within the bottom of box top  225  by a pair of lugs  269  which are slidably received in a pair of channels  269 A formed in lower rectangular portion  233  of box top  225  and then by a pair of screws  274  or other type fasteners. Retaining bracket  273  can be easily removed from valve box  200  together with support ring  271  and split ring  270  for ease of repair should the need arise in the future. 
     Ring  270  includes four outwardly projecting studs  275  which are slidably received in four channel forming lugs  277  projecting upwardly from O-ring support ring  271  which assembles stop ring  270  and support ring  271  within the box top  225 . Ring  270  has a cylindrical inner channel  281  in which is seated the bottom circular edge  282  of sleeve  257 . Top opening  254  of box top  225  slidably receives an end of a rigid conduit  9  therein and is secured usually by some type of an adhesive. The two semicircular pieces which form ring  270  are joined by a pair of pins  275 A ( FIGS. 20B and 25 ). 
     It is readily understood that ring  270  can be a single piece and not a split ring as described above and which provides some resistance to the hose being pulled out of valve box  200  but not prevent it from being removed therefrom. This will enable the hose to be replaced if necessary, without removing the valve box from the wall. 
     O-ring support ring  271  has an outer u-shaped channel  272  in which is secured an outer O-ring  280  and an inner annular ledge  283  on which is supported an inner O-ring  284 . Inner and outer O-rings  284  and  280  of support ring  271  form an upper sealing assembly  310  for engaging a debris pickup nozzle handle indicated generally at  288 , as shown in  FIG. 22A , the function of which is described further below. 
     A length of a usual type of a flexible vacuum cleaning hose  285  is slidably mounted within the interior of conduit  9  and has a distal end  286  and a nozzle end  287  on which is mounted a nozzle handle  288 . Referring to  FIGS. 20B, 21C and 22A , a hose plug indicated generally at  289 , is mounted in distal end  286  of hose  285  by inserting a cylindrical tubular end section  290  into the interior bore  291  of hose  285  and secured therein by an adhesive, friction fit, threaded connection or other type of securement means. The top end of hose plug  289  is curved downwardly and forms a bottom annular horizontally extending ledge  293  against which is seated a sealing ring  294 . Sealing ring  294  is formed of a flexible material, preferably a felt-type of material, and has an annular configuration with an outer diameter just slightly smaller than the inside diameter of conduit  9 . An annular button release ring indicated generally at  295 , is secured to and extends about cylindrical tubular end section  290  of plug  289  and clamps sealing ring  294  in position against ledge  293 . Ring  295  preferably is secured on end section  290  by an adhesive or other type of attachment. Ring  295  is formed with an annular channel  304  having a pair of camming surfaces  296  which are separated by a pair of diametrically opposed vertically extending grooves  292  the function of which are discussed below ( FIGS. 25 and 26 ). 
     Nozzle handle  288  is of a usual construction having a cylindrical elongated end  297  which terminates in a debris pickup end opening  298  ( FIGS. 20A and 22A ). End  297  flares outwardly into a cylindrical hose attachment end  299  into which the nozzle end  287  of hose  285  is secured by an adhesive, threaded attachment or other type of securement means. 
     Hose  285  is of a usual construction used for central vacuum cleaning systems and has sufficient flexibility to move into and out of valve box  200  and around bends in the conduit when manipulated by an individual during use and which slides easily along the interior of conduit  9  yet provides a sliding vacuum seal therebetween by sealing ring  294 . Hose  285  can be the type which is non-extendable or stretchable as used in many types of vacuum cleaning systems within the concept of the present disclosure. 
     The other edges  215 A of housing side walls  215 , edge  219 A of bottom wall  219  and edge  218 A of top wall  218  form front end opening or port  221  through which nozzle handle  288  and hose  285  extend from for performing a debris pickup cleaning operation and then retracted into the housing for subsequent storage in the interior chamber  214  of housing  212 . Preferably, an outer closure door  300  ( FIG. 21B ) is pivotally mounted at the upper end of lower portion  213  of housing  212  at the junction with box top  225  for opening and closing front end opening  221  in order to conceal interior chamber  214  of lower portion  213  and to provide an attractive faceplate for valve box  200  when mounted on wall stud  201  or other support structure. Door  300  is pivotably mounted with respect to housing  212  by a pivot pin  302  which extends through a flange  301  formed on and extending outwardly from a door mounting frame indicated generally at  303 . Door mounting frame  303  has a rectangular outer frame  303 A and a rectangular inner frame  303 B which defines a rectangular opening  303 C. Inner frame  303 B extends perpendicularly from outer flange  303 A. 
     Door frame  303  is adjustably mounted on lower portion  213  of housing  212  by inner frame  303 B forming a sliding friction fit with the interior surfaces of side walls  215 , bottom wall  219  and top wall  218  as shown in  FIGS. 22A and 22B  to compensate for different thicknesses T 1  and T 2  of wall boards  206 . The bottom member of inner frame  303 B is slidably received beneath ramp  240  of bottom bracket  239  to assist in retaining door frame  303  on lower portion  213  of housing  212 . Door frame  303  is secured to housing  212  by a plurality of fasteners  306  which extend into preformed holes  306 A formed in the corners of lower portion  213 , as shown in  FIGS. 20 and 20A . 
     One or more mounting flanges  305  are formed integrally with or attached to one or both side walls  215  of lower portion  213  and extend outwardly therefrom for mounting valve box  200  to wall stud  204  or other support structure, which could be the aluminum or wood studs of a building, a concrete wall or other type of material from which the structure is formed. Door  300 , door frame  303 , mounting flanges  305  and valve box  200  can be formed of various materials such as of a rigid molded plastic or various other types of metal materials without affecting the concept of the invention. 
     In accordance with one of the features of the invention, lower portion  213  of housing  212  and box top  225  and their relationship to each other and to door  300  do not require or form an air-tight structure since such a condition is not required due to the unique double seal arrangement described further below. 
     The manner of use of valve box  200  within the vacuum system shown in  FIG. 18  and the interrelation and function of the various components discussed above are now described in detail. As previously stated, one of the main advantages of valve box  200  is that it is not a sealed box as in prior art inlet valves used in central vacuum cleaning systems. This feature is achieved by providing upper and lower seals in housing  212  by the use of lower bottom bracket  239  containing sealing ball  249  and upper sealing assembly  310  containing O-rings  280  and  284  with additional sealing assistance by sealing ring  294  on the distal end of hose  285  and the inner surface of sleeve  257  as shown in  FIGS. 22A and 24 . 
     When nozzle handle  288  is in a retracted stored position ( FIGS. 19, 22A and 23 ), ball  249  is biased upwardly by coil springs  243  into sealing engagement with end opening  298  of the nozzle handle. This seals the vacuum created within hose  285  by vacuum source  5  from the surrounding atmosphere. Also, when nozzle handle  288  is in this retracted stored position, upper sealing assembly  310  and in particular inner and outer O-rings  280  and  284  will seal the vacuum created within conduit  9  from the ambient atmosphere and interior of housing  212  ( FIG. 6A ). Thus both the vacuum created within the hose and that created within the connecting conduit is completely sealed within housing  212 . This avoids the necessity of providing an air-tight box as required by other inlet valves for central vacuum cleaning systems. 
     When an individual desires to perform a cleaning operation, the individual merely grasps nozzle handle  288  and pulls outwardly, as shown by arrow A in  FIG. 24 , which will automatically cause ball  249  to be depressed downwardly within central channel  251 . Continuing pulling outwardly on nozzle handle  288  will slide the hose along the interior of conduit  9  until a desired length is pulled from valve box  211  for use in a debris pickup cleaning operation. Hose plug  289 , and in particular sealing ring  294 , will provide a sliding seal within the interior of conduit  9  throughout its length of travel therein. This provides a sufficient seal so that most of the vacuum within conduit  9  is applied to end opening  298  of nozzle handle  288 . After a cleaning operation has been completed, the user merely pushes the nozzle handle and hose back into valve box  200  through front end opening  221  in an opposite direction to that of arrow A in  FIG. 24  until the end of the nozzle handle engages ramp  240  of bottom bracket  239  and upon continuing moving inwardly will easily depress ball  249  against springs  243  until the nozzle handle is fully seated in the housing after which the springs will bias ball  243  into sealing engagement with end opening  298  of nozzle handle  288  as shown in  FIG. 22A . Nearly simultaneously with ball  249  sealing end opening  298 , O-ring  284  will provide an air-tight seal with cylindrical outer surface  299 A of hose attachment end  299 . This operation is performed relatively easy by a user merely pushing the nozzle handle inwardly resulting in the hose sliding further into conduit  9 . The vacuum created within the conduit also assists in pulling the hose into conduit  9 . To remove nozzle  288  from housing  212 , a user merely grasps cylindrical end  297  of the nozzle handle and pulls outwardly automatically depressing ball  249  enabling the hose to be easily pulled from housing  212 . 
     Another advantage of the present disclosure is that hose stop ring  270  in combination with buttons  267  prevent the distal end of the hose from being pulled completely from valve box  200 . As shown in  FIGS. 24-26 , upon distal end  286  of hose  285  reaching valve box  200 , buttons  267  by the biasing force of springs  265  will snap into engagement within annular channel  304  of ring  295  and into engagement with camming surfaces  296  which prevents further movement of the hose in an outwardly direction from housing  212 . After the cleaning operation has been performed, the individual merely will grasp the portion of hose  285  adjacent front end opening  221  of housing  212  and upon a slight rotation thereof will move camming surfaces  296  along the ends of buttons  267  until the buttons reach vertically extending grooves  292  (see  FIGS. 24 and 26 ) whereupon a slight inward pressure on the hose coupled with the vacuum applied to conduit  9 , will enable the hose to slide easily inwardly into the conduit until nozzle handle  288  reaches housing  212 . Again, upon reaching this position, the nozzle handle will move easily along ramp  240  and over ball  249  until the ball snaps into sealing engagement with the open end of nozzle  288 . Thus, a user will merely rotate the hose and push slightly inwardly which will automatically disengage the buttons from end plug  266  enabling the hose to be withdrawn easily into the conduit. The movement of nozzle handle  288  into the interior of housing  212  will automatically engage inner O-ring  284  of sealing assembly  310  with the external surface of nozzle  288 . Thus, again upon replacing nozzle end  288  into housing  212 , the vacuum within the hose and nozzle is sealed by ball  249  and the vacuum within conduit  9  is sealed by sealing assembly  310 . 
     Also as shown in  FIG. 25 , as distal hose end  286  reaches box top  225  upon the full extension of the hose from within the valve box, sealing ring  294  will move along tapered annular surface  260 B of sleeve  257  until providing a seal against cylindrical inner wall  260 A of annular wall  259  as shown in  FIG. 24 . This creates an effective seal enabling the full power of the vacuum to be applied to the interior of hose  285 . Thus, while the hose is being pulled from within valve box  211 , a seal is applied by sealing ring  294  along the inside of conduit  9  and which will be maintained throughout the movement of hose  285  through conduit  9  and into box top  225  to its full extended position as shown in  FIG. 25 . Sealing ring  294  will maintain a sliding seal with the interior of conduit  9  as the hose is retracted back into conduit  9  until nozzle handle  288  reaches its final retracted stored position as shown in  FIGS. 22A and 22B  where an effective seal is created by ball  249  and upper seal assembly  310  provided by inner O-ring  284  and outer O-ring  280 . Ball  249  provides a seal for the vacuum within the hose and nozzle handles, and upper seal  310  provide an effective seal from any area on the outside surface of the hose. 
     A modified embodiment of valve box  200  is shown in  FIG. 27  and is indicated generally at  320 . Valve box  320  is nearly identical to that of valve box  200  discussed above, with the main difference being that a top box  321 , which is nearly identical to box top  225 , is at an angle of approximately 10 degrees with respect to a lower rectangular portion  322  which again is similar or nearly identical to lower portion  213  of valve box  200 . This angular relationship facilitates the outward pulling movement on nozzle handle  288  making it easier to remove the nozzle handle from within the valve box and/or replacing the same therein. It also reduces the amount of force needed for nozzle handle end to depress ball  249 . The other components of this embodiment are similar or the same as that described above with respect to valve box  200  and thus are not described in further detail. 
     It is readily understood that an ON/OFF switch (not shown) could be mounted in valve box  200  or closely adjacent thereto and connected by wires to vacuum source  5  for controlling the vacuum source as used in many types of prior art valves. 
     While various inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the inventive teachings is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure. 
     The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.” The phrase “and/or,” as used herein in the specification and in the claims (if at all), should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and/or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to “A and/or B”, when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc. As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and/or” as defined above. For example, when separating items in a list, “or” or “and/or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of” or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e. “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the claims, shall have its ordinary meaning as used in the field of patent law. 
     As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and/or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc. 
     In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures. 
     An embodiment is an implementation or example of the present disclosure. Reference in the specification to “an embodiment,” “one embodiment,” “some embodiments,” “one particular embodiment,” or “other embodiments,” or the like, means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments, of the invention. The various appearances “an embodiment,” “one embodiment,” “some embodiments,” “one particular embodiment,” or “other embodiments,” or the like, are not necessarily all referring to the same embodiments. 
     If this specification states a component, feature, structure, or characteristic “may”, “might”, or “could” be included, that particular component, feature, structure, or characteristic is not required to be included. If the specification or claim refers to “a” or “an” element, that does not mean there is only one of the element. If the specification or claims refer to “an additional” element, that does not preclude there being more than one of the additional element. 
     In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. 
     Moreover, the description and illustration of the preferred embodiment of the disclosure are an example and the disclosure is not limited to the exact details shown or described.