Abstract:
A multiple direction railroad gate release mechanism which is attached between the mount arms of a railroad gate actuator and a crossing arm to prevent breakage of the crossing arm due to impingement in either a frontal or rearward direction by a vehicle or other outside force. A pivot arm assembly allows a released movement of the crossing arm in reaction to frontal impingement and returns the crossing arm to the original and detent position subsequent to an impingement in order to maintain grade crossing protection. A spring return assembly, a shock absorber, and a detent plunger act to return the pivot arm assembly and attached crossing arm to a neutral detent position. The pivot arm assembly allows for rotation about a single pivot point of at least ±/−90 degrees relative to the longitudinal axis of the attached crossing arm.

Description:
CLAIM OF PRIORITY 
       [0001]    This non-provisional patent application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 62/328,333, entitled “MULTIPLE DIRECTION RAILROAD GATE RELEASE MECHANISM,” filed on Apr. 27, 2016, which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    Railroad crossing grades are protected by railroad grade crossing arms which are stored substantially in a vertical position and which are actuated by railroad gate actuators. The actuators reorient the crossing arms to a horizontal position across a railroad crossing grade. The crossing arms warn operators of vehicles of oncoming train traffic and physically place a barrier in the form of a crossing arm at both sides of the railroad crossing grade to discourage and prevent the passage of a vehicle into the railroad crossing grade 
         [0003]    Motorists unaware of the movement of a crossing arm may impinge either the front or the back of the crossing arm to the extent that physical damage may occur whereby the crossing arm is broken or parted from the railroad gate actuator. In some situations, the motorist may physically damage a first crossing arm or may avoidingly maneuver the motor vehicle around the end of the first crossing arm whereby damaging impact with a second opposed crossing can result. Such an occurrence can compromise the safety of the railroad grade crossing in that other motorists will not be warned of impending danger due to the destruction of one or more of the crossing arms. Such occurrences will compromise safety as well as add a financial maintenance burden. 
       Overview 
       [0004]    The present disclosure provides a railroad gate release mechanism, and in particular, a multiple direction railroad gate release mechanism which allows for maintaining the structural integrity of a railroad grade crossing arm when struck from one or more directions by an automotive vehicle. Although a multiple direction railroad gate release mechanism is described, the release mechanism can be used for other gates such as, but not limited to, parking lot gates, restricted access gates, road closure gates, toll gates, crowd control gates and the like. 
         [0005]    The present inventors have recognized, among other things, that a problem to be solved can include reducing the physical damage to crossing arms from motorists. Depending on where a motorist may contact a crossing arm the amount the crossing arm needs to pivot before structural damage occurs can vary. The present inventors have solved the problem by providing a railroad gate release mechanism that can rotate +/−90 degrees relative a neutral position. Thus, regardless of the impact point, the railroad gate release mechanism of the present disclosure reduces the risk of physical damage by allowing for 90 degrees of rotation and thereby clearing the crossing arm from the moving motorist from the passageway. 
         [0006]    Additionally, the present inventors have recognized that the force required to move the crossing arm from the neutral position may not be the same in every situation where the railroad gate release mechanism is used. The present inventors have solved this problem by providing a railroad gate release mechanism with an adjustable force. That is, a user can manually adjust the force needed to move the crossing arm from the neutral position. For example, in areas of high wind or during storms, the force required to move the crossing arm can be increased such that the crossing arm will not move from the neutral position due to non-motorist reasons such as high winds. 
         [0007]    There may be times when the railroad gate release mechanism is not needed and gate release mechanism of the present disclosure provides for a locked position. The present inventors have provided two locking features. The first includes locking the crossing arm in a locked position including a locking bolt that will not allow the crossing arm to move from the neutral position within causing physical damage to the crossing arm. The second includes locking the crossing arm in a fixed position with a shear bolt such that, before structural damage occurs, the shear bolt will break when a predetermined force is applied. Thus, if a force is applied such that the shear bolt breaks, the only replacement part would be the shear bolt versus an entire crossing arm and/or other components of the gate release mechanism. 
         [0008]    In additional embodiments, the gate release mechanism can include a counter such that after installation of the gate release mechanism, a user can look to see how many times the gate release mechanism has been utilized providing valuable information to a user. 
         [0009]    This overview is intended to provide an overview of subject matter of this document. The overview discusses the inventive subject matter in a general, non-limiting, manner to provide an introduction to the more detailed description provided below in reference to the various figures included in this disclosure. It is not intended to provide an exclusive or exhaustive explanation of the invention. The detailed description is included to provide further information about the present document. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document. 
           [0011]      FIG. 1  illustrates a gate release mechanism, according to some example embodiments. 
           [0012]      FIG. 2  is a perspective view of a portion of the gate release mechanism, according to some example embodiments, along with portions of mount arms and a crossing arm which are associated therewith in use. 
           [0013]      FIG. 3  is an exploded perspective view of the components of the gate release mechanism, according to some example embodiments. 
           [0014]      FIG. 4  is another view of the exploded perspective view of the components of the gate release mechanism, according to some example embodiments. 
           [0015]      FIG. 5  a top view of a portion of the gate release mechanism assembly, according to some example embodiments. 
           [0016]      FIG. 6  is a perspective view of the portion of the gate release mechanism shown in  FIG. 6 . 
           [0017]      FIG. 7  a top view of the portion of the gate release mechanism shown in  FIG. 6  in a non-neutral position. 
           [0018]      FIG. 8  is a perspective view of the portion of the gate release mechanism shown in  FIG. 8 . 
           [0019]      FIG. 9  is a perspective view of a portion of the gate release mechanism showing adjustment of the spring force of a decent plunger, according to some example embodiments. 
           [0020]      FIG. 10  is a top view of a portion of the gate release mechanism at the neutral position, according to some example embodiments. 
           [0021]      FIG. 11  is a top view of the portion of the gate release mechanism shown in  FIG. 11 , at a non-neutral position. 
           [0022]      FIG. 12  is a perspective view of a gate release mechanism including a counter and a locking bolt, according to some example embodiments. 
           [0023]      FIG. 13  is a close-up of a window of the counter, according to some example embodiments. 
           [0024]      FIG. 14  is a perspective view of the gate release mechanism illustrating the location of the counter, according to some example embodiments. 
           [0025]      FIG. 15  is a perspective view of the gate release mechanism including the counter where the housing of the counter is transparent, according to some example embodiments. 
           [0026]      FIG. 16  is a perspective view of a portion of the gate release mechanism, according to some example embodiments. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    The present disclosure is for a railroad gate release mechanism, and in particular, for a multiple direction railroad gate release mechanism which allows for maintaining the structural integrity of a railroad grade crossing arm when struck from one or more directions by, for example, an automotive vehicle. Although a multiple direction railroad gate release mechanism is described, the release mechanism can be used for other gates such as, but not limited to, parking lot gates, restricted access gates, road closure gates, toll gates, crowd control gates and the like. 
         [0028]      FIG. 1  shows the use of the multiple direction railroad gate release mechanism  10  (also referred to herein as “gate release mechanism”) of the present disclosure. A railroad gate actuator  12  is shown in the actuated position to position the multiple direction railroad gate release mechanism  10  and attached crossing arm  14  in a horizontal position. The multiple direction railroad gate release mechanism  10  is mounted between the ends of the mount arms  16   a  and  16   b  ( FIG. 2 ) and the crossing arm  14  is mounted to the multiple direction railroad gate release mechanism  10 . 
         [0029]    As discussed herein, the present disclosure provides a multiply: direction railroad gate release mechanism that can rotate  90  degrees in either direction with an automatic return to a neutral position, and provides for adjustment of the force required to break away from the center or neutral position. The gate release mechanism  10  allows the crossing arm  14  to rotate  90  degrees in either direction while rotating about a single pivot point as well as an adjustable detent force that changes the force necessary to move the gate arm (also referred to herein as “crossing arm”) from the neutral position. 
         [0030]      FIG. 2  is perspective view of the railroad gate release mechanism  10  of the present disclosure showing its connecting relationship between mount arms  16   a  and  16   b  of the railroad gate actuator  12  and the crossing arm  14 . Top and bottom mounting brackets  18  and  20  in the form of channels accommodate attachment of the mount arms  16   a  and  16   b . The crossing arm  14  is coupled to a pivot arm assembly  30  of the multiple direction railroad gate release mechanism  10 . As shown in  FIG. 2 , the crossing arm  14  is shown in a horizontal position, such as for stopping traffic at a railroad grade crossing. The crossing arm  14  is at a neutral position in  FIG. 2  and the longitudinal axis of the crossing arm  14  is perpendicular to the longitudinal axis of the mounting brackets  18  and  20 . 
         [0031]    Multiple views of the gate release mechanism  10  are included for a full understanding of the present invention.  FIGS. 3 and 4  are exploded views of the components of the gate release mechanism  10 . In the disclosure, a plurality of nuts, bolts, and lock washers are secured through a plurality of holes in a plurality of diverse components as is common practice in the art and as are shown or indicated in engagement or alignment wherever practicable or suitable in the accompanying illustrated figures, 
         [0032]    Partial or fully visible components of the gate release mechanism  10  include opposing top and bottom mounting brackets  18  and  20  in the form of a channel, each having a plurality of mounting holes  22   a - 22   n  used in the attachment of mount arms  16   a  and  16   b  of the railroad gate actuator  12 , as well as other holes and features for mounting other components thereto. Opposed top and bottom bearing support plates  24  and  26  are preferably aligned with recessed surfaces on the inwardly facing surfaces of the top and bottom mounting brackets  18  and  20  are suitably secured thereto. The support plate  24  includes a circular recess  30  opening downwardly for the fixed accommodation of a top bearing assembly  32 . The top support plate  24  can include holes  31  to receive pins to couple to the bearing assembly  32 . Also, the bottom bearing support plate  26  includes a circular recess  38  opening upwardly for the fixed accommodation of a bottom bearing assembly  40 . The bottom bearing support plate  26  can include holes  41  for to receive pins to couple the support plate  26  to the bearing assembly. 
         [0033]    The pivot arm assembly  30  is aligned between the top and bottom bearing support plates  24  and  26 , respectively, and is mounted and pivotally secured therebetween by the pivot pin  54  which is in close intimate contact with the top bearing assembly  32  and the bottom bearing assembly  40 . The pivot pin  54  is the single pivot point  55  that the crossing arm  14  rotates about. The pivot arm assembly  30  includes, in part, a swing arm  25  configured to be coupled to the crossing arm  14  and a detent cam  34 . 
         [0034]    As shown in  FIG. 7 , the detent cam  34  includes a first guide surface  38 , a second guide surface  39 , and a semicircular detent  36 . The semicircular detent  36  is positioned between the first guide surface  38  and the second guide surface  39 . The first and second guide surfaces  38 ,  39  each include a flat portion  41 ,  44  and a curved portion  42 ,  46 . In an example embodiment, the curved portions  42 ,  46  have a constant radius of curvature. The swing arm  25  is coupled to the detent cam  34  such that the swing arm  24 , the pivot point  55  and the semicircular detent  36  are aligned with each other along a longitudinal axis  43  of the swing arm  25 . 
         [0035]    The semicircular detent  36  is formed by a semicircular cutout in the detent cam  34  and configured to receive the detent roller  37  when the swing arm  25  is at a neutral position (shown in  FIGS. 5-6 ). The detent roller  37  is configured to move along the first guide surface  38  when a force acting on the swing arm  25  is in a first direction and the detent roller  37  is configured to move along the second guide surface  39  when a force acting on the swing arm  25  is in a second direction, opposite the first direction. In  FIGS. 8 and 9 , a force was applied to the swing arm  25  in the second direction moving the detent roller  37  from the neutral position within the semicircular detent  36  and along the second guide surface  39 . 
         [0036]    The pivot arm assembly  30  also includes a detent lever  49  and a detent plunger  50 . The detent plunger  50  is coupled to the detent lever  49  and configured to apply a force to the detent roller  37  to force the detent roller  37  into the semicircular detent  36 . In a neutral position, the detent roller  37  is positioned within the semicircular detent  36  via the detent plunger  50  which forces the detent roller  37  into the semicircular detent  36 . As discussed herein, the detent roller  37  can be forced from the semicircular detent  36  when a force acting on the swing arm  25  (e.g., a force acting on a crossing arm attached to the swing arm  25 ) is greater than the force of a resilient member  56  and pushes the plunger shaft  59  into the plunger housing  51 . As discussed herein, the force of the resilient member  56  can be adjusted via the detent plunger  50 . 
         [0037]    The detent plunger  50  includes a plunger housing  51 , the resilient member  56  positioned within the plunger housing  51 , and the plunger shaft  59 . The plunger housing  51  includes a first end plate  52  and a second end plate  53 . The plunger housing  51  can also include a tubular housing  67  (shown in  FIG. 4 ) extending between the first and second end plates  52 ,  53 . The resilient member  56  is positioned within the plunger housing  51  and has a first end  57  and a second end  58 . The resilient member  56 , e.g., a spring, can be in a compressed state. That is, the length of the plunger housing  51  between the first and second end plates  52 ,  53  is such that the resilient member  56  is in a compressed state. The plunger shaft  59  has a first end  60  and a second end  61 . The plunger shaft  59  is moveable relative to the plunger housing  51  and the first end  60  of the plunger shaft  59  is coupled to the detent lever  49 . The second end of the plunger shaft  61  defines a shoulder  66  that is positioned inside of the plunger housing  51  and is configured to abut an inside surface  62  of the first end plate  52  and the first end  57  of the resilient member  56 . 
         [0038]    As discussed herein, the force of the resilient member  56 , which is the force required to move the detent roller  37  from the semicircular detent  36  (i.e., move the swing  25  from the neutral position to a non-neutral position) is adjustable. The detent plunger  50  can include an adjuster  67  that includes an adjustment bolt  63  extending through and threadeably engaged with an aperture  64  of the second end plate  53  and an adjustment washer  65  coupled to the adjustment bolt  63  and positioned within the plunger housing  51  and configured to abut the second end  58  of the resilient member  56 . The detent roller  37  can be forced form the semicircular detent  36  when the force acting on the swing arm  25  (via a crossing arm  14 ) is greater than the force of the resilient member  56 . 
         [0039]    By moving the adjustment bolt  63  at the end of the plunger housing  51 , the force applied to the detent roller  37  can be adjusted and thereby increase or decrease the force required to move the detent roller  37  out of the semicircular detent  36 . For example, if the adjustment bolt  63  is tightened and the distance between the first end plate  52  and the washer  65  is reduced, the plunger force acting on the detent roller  37  is increased. As the adjustment bolt  63  is loosened and the distance between the first end plate  52  and the washer  65  increases, the plunger force acting on the detent roller  37  is reduced. As discussed herein, even when the washer  65  is abutting the second end plate  53 , the resilient member  56  is in a compressed state and provides a minimum force to the detent roller  37 . 
         [0040]    By having an adjustable force, the gate release mechanism  10  can be used in various situations without having to replace pieces of equipment. For example, the same gate release mechanism  10  can be used in a high wind areas and low wind areas. The only change needed would be to adjust the force via the adjustment bolt  63 . Further, in various situations, the force required for the detent roller  37  to be pushed out of the semicircular detent  36  may need to change for an assembly at a particular site. For example, a single force may not be appropriate for all times of the year at a site. The adjustable force (e.g., adjustable resilient member force or plunger force) therefore allows a user to continually adjust the plunger force as necessary, without having to replace the entire mechanism. 
         [0041]    The detent lever  49  can include a top detent lever plate  68  and a bottom detent lever plate  69 . The detent roller  37  and the plunger shaft  59  are coupled to and positioned between the top and bottom detent lever plates  68 ,  69 . Further, the detent roller  37  includes a top flange  70  and a bottom flange  71  that assists maintaining alignment of the detent roller  37  and the detent cam  34 . For example, the top flange  70  can be positioned on a top surface of the detent cam  34  and the bottom flange  71  can be positioned on a bottom surface of the detent cam  34 . The detent lever  49  can include a detent lever pivot point  72  about which the detent lever  49  rotates about. The detent lever  49  (including the top and bottom detent lever plates  68 ,  69 ) can include an aperture  73  configured to receive a pin  74  that couples the detent lever  49  to the detent lever frame  75 . The detent lever frame  75  can include a top lever frame plate  76  and a bottom lever frame plate  77 . For example, a top lever frame plate  76  can be positioned on top of the top detent lever plate  68  and the bottom lever frame plate  77  can be positioned on a bottom of the bottom detent lever plate  69 . The pin  74  can extend through the top lever frame plate  76 , the top detent lever plate  68 , the bottom detent lever plate  69 , and the bottom lever frame plate  77 . The detent lever frame  75  can be coupled to the mounting brackets  18 ,  20 . For example, the detent lever frame  75  can be coupled to a support frame  35 that is coupled directly to the mounting brackets  18  and  20 , as discussed herein. 
         [0042]    As shown in  FIGS. 5 and 6 , the swing arm  25  is at a neutral position and the detent roller  37  is positioned within the semicircular detent  36 . The plunger shaft  59  is at the neutral position such that the shoulder  66  of the plunger shaft  69  is abutting the inside surface  62  of the first end plate  52  of the plunger housing  51 . That is, the resilient member  56  is applying the plunger force to the detent roller  37  and the detent roller  37  is positioned within the semicircular detent  36 . 
         [0043]    Referring to  FIG. 9 , the adjuster  67  including the adjustment bolt  63  and washer  65  have been tightened to a maximum setting where the adjustment bolt  63  is advanced as far as it can and is abutting the second end plate  53  of the plunger housing  51 . As shown in  FIG. 9 , the length of the resilient member  56  in the plunger housing  51 , at the neutral position, has decreased thereby further compressing the resilient member  56  and increasing the plunger force being applied to the detent roller  37 . 
         [0044]    If enough force impacts the swing arm  25  (e.g., via the crossing arm or gate) to force the detent roller  37  out of the semicircular detent  36  in the detent cam  34 , then the detent roller  37  is pushed out of the semicircular detent  36  and glides along either the first or second guide surfaces  38 ,  39  of the detent cam  34 . As the detent roller  37  moves along either the first or second guide surfaces  38 ,  39 , the resilient member  56  is compressed, as shown in  FIGS. 7 and 8 . For example, as the detent roller  37  is forced out of the semicircular detent  36 , the detent lever  49  rotates about the detent lever pivot point  72  forcing the plunger shaft  59  to move relative the first end plate  52  and compress the resilient member  56  within the plunger housing  51 . Additionally, the detent cam  34 , the swing arm  25 , and attached crossing arm  14  (as shown in  FIG. 2 ) can rotate about the pivot point  55  up to at least +/−90 degrees. As shown in  FIGS. 2 and 3 , swing stops  102  and  104  are mounted to the device such that the swing arm  25  does not rotate past 90 degrees. 
         [0045]    A locking aperture can be formed through the detent lever and the detent frame such that when a locking bolt  29  is placed through the locking aperture the swing arm  25  is not moveable without causing physical damage to the device. For example, this may be beneficial during a hurricane or storm. In additional embodiment, the locking bolt can be replaced with a shear bolt such that the swing arm  25  is not moveable but if enough pressure is applied the shear bolt will break prior to breaking other components of the device. 
         [0046]    Once the force acting on the swing arm  25  stops, a spring return assembly  80  is configured to return the swing arm  25  from rotation (at a non-neutral position) about the pivot point  55  and back to the neutral position. The spring return assembly  80  can include a first spring return housing  81  and a second spring return housing  81 ′. The first and second spring return housing  81 ,  81 ′ can be secured in a support bracket  35  that can be coupled to the mounting brackets  18 ,  20 . The first spring return housing  81  and the second spring return housing  82  can each include one or more resilient members  89 a- 89 n (referred to collectively as “resilient members  89 ”). The number and length of the resilient members  89  can be determined by various characteristics including a desired travel distance (compressibility distance of the resilient members to move the swing arm  25  90 degrees), a desired length of the first and second spring return housings  81  and  82 , and desired return force. As discussed herein, the number of spring housings and resilient members included can be selected such that the desired travel distance and return force is achieved while minimizing the length of the first and second spring return housings  81 ,  82 . 
         [0047]    The first and second spring return housings  81 ,  81 ′ can be identical. Reference to the first spring return housing  81  will be referenced for clarity. The first spring return housing  81  can include a first end  95  and a second end  96 . The first end  95  include openings  97  which a chain  83  extends and is coupled to the one or more resilient members  89  within the spring return housing  81 , which allows for the 90 degree rotation. 
         [0048]    As shown in  FIG. 10 , one of the resilient members  89  is removed to show the anchor  89 . The anchor  89  includes a chain engagement end  90 , an elongated shaft  91 , and a compression washer  92 . The resilient members  89  define a first end  93  and a second  94 . The first end  93  is configured to abut an inside surface of the first end  95  of the spring return housing  81  and the second end  94  is configured to abut the compression washer  92  such that the compression washer  92  is between the second end  92  of the resilient member  89  and the second end of the spring return housing  81 . The chain engagement end  90  and the elongated shaft  91  can extend through the resilient members  89  and the compression washer  92  is configured to abut a second end  93  of the resilient members  89 . In  FIG. 10 , the swing arm  25  is in the neutral position and the compression washer  92  is abutting the second end  96  of the spring return housing  81 . The resilient members  89  at the neutral position can be in a pre-compressed state. Any rotation of the swing arm  25  in either direction pulls the chains  83 ,  83 ′ around rollers  85 ,  85 ′ and between rollers  86 ,  86 ′ and  87 ,  87 ′, which pulls the anchor  88 ,  89 ′ within the spring return housings  81 ,  82  to the left, as shown in  FIG. 11 , to compress the resilient member  89 . 
         [0049]    Having the chain  83  coupled to the swing arm  25  and the resilient members  89 , the spring force is transmitted to swing arm  25  (and the gate coupled thereto). As the gate  14  (and swing arm  25 ) rotates, the resilient members  89  compress as the anchor  89  is pulled toward the left side of the spring return housing  81 . In on example, there are two chains  83 ,  83 ′and two return spring housings  81 ,  81 ′. The stack of resilient members  89 ,  89 ′ are compressed to fit into the return spring housings  81 ,  81 ′, thereby providing a return force near center that is high, the return force at full swing is only slightly higher, and the gate arm can swing a full  90  degrees in both directions, 
         [0050]    The gate release mechanism  10  can include a shock absorber  33  that is coupled to the detent cam  34  and pivotally secured to a support bracket  35  (shown in  FIG. 2 ). The shock absorber  33  when moved to a compressed position allows for the rapid rotational movement of the pivot arm assembly  30  from and beyond the neutral detent position during impingement of the crossing arm  14 . The shock absorber  33  allows for a slower rate of movement when returning to the centered neutral position to suitably control the return rate of the pivot arm assembly  30  subsequent to impingement of the crossing arm  14 . 
         [0051]    Referring back to  FIG. 2 , mounting brackets  15  can be used to secure the gate  14  to the swing arm  25 . Service pivot point  17  can be the pivot point when the mounting brackets  15  are removed and the gate return mechanism does not wish to be used, e.g., during servicing. When the mounting brackets  15  are removed, the gate  14  can still be coupled to the swing arm  25  but not to the detent cam  34  such that the gate  14  can be rotated about service pivot point  17  and not initiate the detent cam  34  to rotate. 
         [0052]      FIGS. 12-16  illustrate a counter  110  that can be coupled to the mounting bracket  18 . The mounting bracket  18  can include a window  112  that can display a number. The number is the number of times the gate release mechanism  10  has been activated. The counter can include a cable wire  114  that can be coupled to the detent frame  75  and detent lever  47  and increase the number every time the detent roller  37  moves from the neutral position. 
         [0053]    Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein. 
         [0054]    Although an overview of the inventive subject matter has been described with reference to specific example embodiments, various modifications and changes may be made to these embodiments without departing from the broader scope of embodiments of the present disclosure. Such embodiments of the inventive subject matter may be referred to herein, individually or collectively, by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any single disclosure or inventive concept if more than one is, in fact, disclosed. 
         [0055]    The embodiments illustrated herein are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed. Other embodiments may be used and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. The Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various embodiments is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled. 
         [0056]    As used herein, the term “or” may be construed in either an inclusive or exclusive sense. Moreover, plural instances may be provided for resources, operations, or structures described herein as a single instance. Additionally, boundaries between various resources, operations, modules, engines, and data stores are somewhat arbitrary, and particular operations are illustrated in a context of specific illustrative configurations. Other allocations of functionality are envisioned and may fall within a scope of various embodiments of the present disclosure. In general, structures and functionality presented as separate resources in the example configurations may be implemented as a combined structure or resource. Similarly, structures and functionality presented as a single resource may be implemented as separate resources. These and other variations, modifications, additions, and improvements fall within a scope of embodiments of the present disclosure as represented by the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. 
       Various Notes &amp; Examples 
       [0057]    Each of the following non-limiting examples can stand on its own, or can be combined in various permutations or combinations with one or more of the other examples. 
         [0058]    The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention can be practiced. These embodiments are also referred to herein as “examples.” Such examples can include elements in addition to those shown or described. However, the present inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein. 
         [0059]    In the event of inconsistent usages between this document and any documents so incorporated by reference, the usage in this document controls. 
         [0060]    In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. 
         [0061]    The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. §1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.