Abstract:
An appliance latch receives a strike when the appliance lid is closed and provides an electrically activated lock holding the lid closed during portions of the wash cycle that might present a hazard. The strike presents two different surfaces to the latch, the first to activate a lock mechanism and the second to activate an anti-tamper switch before the appliance may be actuated thereby reducing the risk of tampering. Invention Claim Summary

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. provisional application 61/911,659 filed Dec. 4, 2013, and hereby incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to home appliances such as clothes washing machines and the like and, in particular, to a lid locking mechanism that is highly resistant to tampering. 
       BACKGROUND OF THE INVENTION 
       [0003]    The spin cycle of a washing machine removes water centrifugally from wet clothes by spinning the clothes at high speed in a spin basket. In order to reduce the possibility of injury to the user during the spin cycle, it is known to use an electronically actuated lock for holding the washing machine lid in the closed position. U.S. Pat. Nos. 6,363,755; 5,823,017; and 5,520,424, assigned to the present assignee and hereby incorporated by reference, describe several locking mechanisms. 
         [0004]    In order to prevent tampering with the lock mechanism, for example, by holding the lid open when the lock is actuated, it is known to provide for lid closure sensing to ensure that the lid is in a proper position before the lock mechanism is engaged. Conventional mechanical lid closure switches can often be defeated by wedging the switch open, for example, with the end of a pencil or the like. U.S. Pat. No 7,251,961, assigned to the assignee of the present invention and hereby incorporated by reference, describes a lid sensor using a magnet and electrical reed switch to detect lid closure. The use of a magnetic actuator reduces the possibility of casual tampering. 
         [0005]    US patent application 2012/0312594, hereby incorporated by reference, describes a lock mechanism in which the magnet is incorporated into a hook or striker that engages the latch. Tampering is detected by requiring that the striker physically move a latch element and magnetically move a separate anti-tampering element. Motion of both elements is detected and required before the appliance can be operated. Common sticks or probes for tampering with the latch will not provide the magnetic interaction with the anti-tampering elements and thus may be distinguished from the actual striker. 
         [0006]    In each case, the use of a magnetically actuated element renders physical tampering difficult. Nevertheless, such magnetic systems add cost and complexity to the latching mechanism that may not be acceptable in all cases. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention provides a latch for appliances that avoids the need for magnetically activated anti-tamper elements and yet provides strong anti-tamper resistance. These twin benefits are obtained by using an anti-tamper element that physically contacts the striker but contacts different features of the striker than those contacted by the other latch elements. A tampering tool is unlikely to duplicate all the necessary features of the striker to both actuate the latch and the anti-tamper feature. 
         [0008]    For example, the anti-tamper element and the latch element may contact different forks of a bifurcation in the striker passing on opposite sides of a ward plate. Alternatively, the anti-tamper element and latch element may contact a front and rear surface of the striker element or a front and bottom surface of the striker. By providing contact with two different features, only a properly shaped striker element can activate the appliance. 
         [0009]    Specifically then, one embodiment of the invention provides an appliance latch assembly having a striker and a corresponding latch for receiving the striker, the striker and latch positionable on an appliance lid and appliance frame. A trap contacts a first feature of the striker to move the trap from a first trap position to a second trap position as the striker is received by the latch and provides a surface holding the striker in the latch when the lock element is in the second trap position. An electrically actuated lock may be actuated to hold the trap in the second position and an anti-tamper operator contacts a second feature of the striker different from the first feature to move from a first operator position to a second operator position when the trap moves to the second operator position. A first electrical switch communicates with the lock to provide an indication that the lock is actuated to hold the trap in the second trap position and a second electrical switch communicates with the anti-tamper operator to provide an indication that the anti-tamper operator is in the second operator position. 
         [0010]    It is thus a feature of at least one embodiment of the invention to provide a simple physically actuable mechanism that resists tampering by common tools. 
         [0011]    The striker may include a joint allowing it to move with the trap. 
         [0012]    It is thus a feature of at least one embodiment of the invention to integrate movement of the striker into the latch operations to further resist tampering with tools that may not be able to negotiate this movement. 
         [0013]    The surface of the trap holding the striker in the latch may hold the striker in engagement against a stationary portion of the latch when the trap moves to the second trap position. 
         [0014]    It is thus a feature of at least one embodiment of the invention to leverage the robustness of the stationary structure of the latch to hold the striker in position. 
         [0015]    The striker may be pivoted for travel perpendicularly to the axis and include a spring urging the striker in a first direction perpendicular to the axis. 
         [0016]    It is thus a feature of at least one embodiment of the invention to provide a consistent location of the striker as it enters the latch while allowing movement. 
         [0017]    The anti-tamper operator and the trap may move in the same direction in parallel to each other when the striker is received by the latch trap and moves from the first trap position to the second trap position and the anti-tamper operator moves from the first operator position to the second operator position. 
         [0018]    It is thus a feature of at least one embodiment of the invention to provide a simple mechanism in which the anti-tamper switch and lock actuated mechanism may be offset in the same direction away from the latch opening. 
         [0019]    The first and second feature of the striker may be different forks of a bifurcation on a front surface of the striker and wherein the different forks of the bifurcation pass on opposite sides of a stationary ward plate when the striker engages the latch. 
         [0020]    It is thus a feature of at least one embodiment of the invention to provide a key-like structure that prevents defeat with a simple blunt tool. 
         [0021]    The striker may provide a hook portion extending generally perpendicularly to a direction of engagement of the striker and the latch and wherein the bifurcation is in the hook portion. 
         [0022]    It is thus a feature of at least one embodiment of the invention to offset the physically contacting portions on a hook to further reduce the likelihood of defeat it with commonly available tools such as pencils. 
         [0023]    Alternatively, the first and second feature of the striker may be a front and rear surface of the striker, and the trap and anti-tamper operator may move in opposite directions as the striker engages the latch and the trap moves from the first trap position to the second trap position and the anti-tamper operator moves from the first operator position to the second operator position. 
         [0024]    It is thus a feature of at least one embodiment of the invention to further resist tampering by requiring simultaneous movement in opposite directions, difficult to obtain with common tools. 
         [0025]    The trap and anti-tamper operator may present a funnel-shaped opening between them receiving the striker so that the striker separates the trap and anti-tamper operator as it is received in the latch. 
         [0026]    It is thus a feature of at least one embodiment of the invention to provide a simple method of providing opposite motion of the trap and anti-tamper operator that effectively require specific dimensions of the striker for proper operation. 
         [0027]    The anti-tamper operator movement may be limited so that separation of the trap and anti-tamper operator as the striker is received within the latch guarantees a predetermined movement of the latch element. 
         [0028]    It is thus a feature of at least one embodiment of the invention to provide opposite motion of the trap and anti-tamper operator while ensuring proper locking. 
         [0029]    Alternatively, the first and second features of the striker may be a front and bottom surface of the striker. 
         [0030]    It is thus a feature of at least one embodiment of the invention to provide not only different critical dimensions of the striker but also dimensions along different axes further obstruct tampering. 
         [0031]    The trap and anti-tamper operator may move in perpendicular directions as the striker engages the latch and the trap moves from the first trap position to the second trap position and the anti-tamper operator moves from the first operator position to the second operator position. 
         [0032]    It is thus a feature of at least one embodiment of the invention to require two axes of movement of a tampering tool to successfully defeat the lock, thereby significantly reducing the possibility of such defeat. 
         [0033]    The electrically actuated lock may be a solenoid and bistable mechanism moving a blocking element between receipt by the trap and removal from the trap with successive energizing of the solenoid and wherein the lock signal is a first energizing and the unlock signal is a second energizing of the solenoid. 
         [0034]    It is thus a feature of at least one embodiment of the invention to provide a latch that can resist power loss as a possible method of defeating the latch. 
         [0035]    Motion of the striker to disengage the striker from the latch when the blocking element is received by the trap may cause an abutting of the blocking element against a frangible portion of the trap which, when broken, prevents activation of the lock switch. The frangible portion of the trap may support a spring element away from an opening into which the blocking element may be received such that removal of the frangible element causes the spring element to occlude the opening. 
         [0036]    It is thus a feature of at least one embodiment of the invention to detect damage to the latch that might prevent operation. 
         [0037]    Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0038]      FIG. 1  is a perspective view and inset fragmentary detail of a top loading washing machine suitable for use with the present invention showing a striker aperture positioned near the front of an upwardly opening lid and showing a downwardly extending striker for engaging a latch when the lid is closed; 
           [0039]      FIG. 2  is a fragmentary planar cross section of the latch and striker of  FIG. 1  (viewed from below) showing a floating mounting of the striker allowing close tolerance interaction between the striker and latch to move a trap element to a retaining and locking position; 
           [0040]      FIG. 3  is a fragmentary perspective view of the striker guided by a sloping surface of the latch into engagement with a trap; 
           [0041]      FIG. 4  is a figure similar to that of  FIG. 3  showing the hook of the striker fully engaged and retained by the trap pushing the trap and an anti-tamper slide forward; 
           [0042]      FIG. 5  is a simplified perspective view of the trap engaging the striker showing the positioning of the anti-tamper slide in an aperture at the front of the trap and showing a bi-stable actuator above the trap for controlling a blocking element descending into the trap to block movement of the trap; 
           [0043]      FIGS. 6  is a top plan view of the hook of the striker with respect to the trap in partial fragment showing engagement of the hook with the trap and the anti-tamper slide; 
           [0044]      FIG. 7 a    is a top plan view of the bi-stable actuator of  FIG. 5  in a first state removing the blocking element from engagement with the trap; 
           [0045]      FIG. 7 b    is a figure similar to that of  FIG. 7 a    showing the bi-stable actuator in a second state engaging the blocking element with the trap to prevent the movement of the trap; 
           [0046]      FIG. 8  is a view similar to that of  FIGS. 7 a    and  7   b,  with the blocking element and supporting lock switch removed for clarity, showing actuation of the solenoid during movement between the states of  FIGS. 7 and 8  such as frees an anti-vibration tooth for clearance of the solenoid plunger; 
           [0047]      FIG. 9  is a side elevational view of the blocking element and lock switch of  FIGS. 5, 7   a  and  7   b;    
           [0048]      FIG. 10  is a figure similar to that of  FIG. 3  showing an alternative embodiment of the invention in which a sloping guide surface in the latch guides the rear of the striker forward to move the trap while simultaneously retracting rearward to control the anti-tamper slide; 
           [0049]      FIG. 11  is a figure similar to that of  FIGS. 3 and 10  showing an alternative embodiment in which a rotating toggle arm actuated by a bottom of the striker is used in place of the anti-tamper slide; 
           [0050]      FIGS. 12 a  and 12 b    are cross-sectional views taken along line  12 - 12  of  FIG. 5  showing engagement of a blocking element within the aperture of the trap and showing a blocking of that engagement when aperture integrity has been compromised through forcing open of the latch; 
           [0051]    Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0052]    Referring now to  FIG. 1 , a top loading washing machine  10  suitable for use with the present invention includes a lid  12  opening upward about a horizontal lid hinge axis  14 . The lid hinge axis  14  is positioned near the top rear edge of the washing machine  10  so that a front edge  16  of the lid  12  may raise and lower to expose and cover an opening  20  through which clothing may be inserted into the spin basket. 
         [0053]    A horizontal surface of the top  22  of the washing machine  10 , at the periphery of the opening  20 , may support a striker aperture  24  extending from a housing  21  of a latch  25  fastened to the underside of the top  22 . The striker aperture  24  opens upward to receive a downwardly extending striker  26  attached to an underside of the lid  12 . Both the striker aperture  24  and the striker  26  are offset parallel to the axis  14  and offset from a center of the front edge  16  so as to minimize interference with loading and unloading the washing machine  10 . 
         [0054]    The top-loading washing machine  10  may also provide for a controller board  11 , for example, including a processor executing a program stored in computer memory. The controller board may receive signals from the latch  25  via harness  82  and from controls  13  accessible to the user to control operation of one or more electric actuator such as motor  15  actuating a spin basket or the like. 
         [0055]    Referring now to  FIG. 2 , the striker  26  may include a downwardly extending arm  28  terminating in a hook portion  30  extending leftward from the arm  28 , as shown in  FIG. 2 , generally toward a user of the washing machine  10 . The upper end of the arm  28  may be mounted to the lid  12  by a hinge element  17  to pivot left and right as indicated by arrows  32  with respect to the lid  12  under restoring spring forces indicated schematically by springs  34 . The hinge element  17  may be a pivot joint with springs  34  or a living hinge having natural resiliency. In this way, the left and right surfaces of the hook portion  30  may translate as may be necessary to accommodate positional tolerances in the manufacture of the washing machine  10  and wear of the washing machine  10  and to provide movement of a trap to be described. 
         [0056]    As the lid is closed, the hook portion  30  moves toward the striker aperture  24  and is guided rightward by a right facing first sloping edge  36  of an aperture bezel  38  defining the striker aperture  24 . The aperture bezel moves the hook portion  30  to position  29   b  with a left edge of the striker  26  aligned at first position  31  with the right edge of an un-retracted trap  40  (shown in a forward, retracted position in  FIG. 2 ). The striker  26  is then urged left by a left facing second sloping edge of ramp  42  so as to push the trap  40  leftward against a restoring spring (not shown in  FIG. 2 ) so that a left edge of an opening in the trap  40  is moved to position  31 ′ as hook portion  30  passes to position  29   c.    
         [0057]    A following surface  33  of the trap  40 , when the trap is moved forward with the striker  26  in position  29   c,  prevents rightward movement of the hook portion  30  when the trap  40  is latched as will be described below, trapping the striker  26  beneath a stationary ledge on the underside of the sloping edge  36 . This serpentine path defined by sloping edges  36  and sloping surface of ramp  42  ensures that the left edge of the striker  26  abuts the leading surface  41  of the trap  40  in close proximity despite tolerance variations between the lid  12  and the top  22  and allows the striker  26  to move the trap  40  to the forward position needed for locking as will be described. 
         [0058]    Referring now to  FIG. 3 , and referring to directions as depicted in that figure, in a first embodiment, the hook portion  30  maybe bifurcated into left and right teeth  37   a  and  37   b  separated by a slot  35 . The right tooth  37   b  may contact the leading surface  41  of the trap  40  to push it forward as described above with respect to  FIG. 2  as the rear edge of the striker  26  is pressed forward by interaction with the ramp  42 . At the same time, the left tooth  37   a  may push against an upwardly extending finger  43  on anti-tamper slide  44 , the latter of which may slide along the axis  27  as will be discussed below. 
         [0059]    An upwardly extending ward plate  45  is attached to the stationary structure of the latch  25  to extend between the leading surface  41  of the trap  40  and the finger  43  on the anti-tamper slide  44  so that, as shown in  FIG. 4 , the hook portion  30  may engage the trap  40  and push the trap  40  along axis  27  by the interaction of tooth  37   b  and leading surface  41 , and push the upwardly extending finger  43  on anti-tamper slide  44  by tooth  37   a,  only if slot  35  is present allowing the hook portion  30  to pass around the ward plate  45 . The ward  45  thus defeats actuation of the latch  25  by a non-bifurcated probe. 
         [0060]    Referring now to  FIG. 5 , the sliding trap  40  is normally biased rightward by a biasing spring showed schematically as spring  52  to engage hook portion  30  when hook portion  30  is moved into position  29   c  shown in  FIG. 2 , then to hold the hook portion  30  underneath the stationary latch structure of the aperture bezel  38  against upward motion. The trap  40  includes an aperture  63  at its left edge. When the trap  40  is moved leftward, forward capturing the hook portion  30 , the aperture  63  aligns with a blocking element  54  which may descend into the aperture  63  from an actuator mechanism  55  positioned above the trap  40 . In this configuration, rightward movement of the trap  40  is stopped by interference between a left surface of the blocking element  54  abutting a blockade surface  53  forming a left wall of the aperture  63 . Thus, the trap  40  acts as a trap to hold the striker  26  in position when the blocking element  54  acts as a blocking element to the trap  40 . 
         [0061]    Referring now to  FIGS. 5, 9, 12   a  and  12   b,  the blocking element  54  may be moved downward under the influence of a flexible leaf spring  56 . The flexible leaf spring  56  holds one of a pair of contacts of a lock switch  57  indicating proper locking of the latch  25  when the blocking element  54  is lowered and the contacts connect, closing the lock switch  57 . At this time, the blocking element  54  may only be disengaged by action of a bistable solenoid mechanism  60  (shown schematically in  FIG. 5  and described below) providing a wedge element  58  that may lift the leaf spring  56  to raise the blocking element  54  by contacting a sloped portion  59  of the leaf spring  56 . Referring still to  FIG. 6 , motion of the anti-tamper switch along axis  27  closes anti-tamper switch  50  allowing operation of the lock. 
         [0062]    It will be appreciated that the solenoid  62  may be replaced with a variety of other actuator types including thermal actuators (such as bimetal actuators, muscle wire, or wax motors) or mechanisms such as DC motors with rack and pinion gearing or lead screws or the like. 
         [0063]    While the bistable solenoid mechanism  60  prevents defeat of the lock mechanism by removing power from the appliance, the invention also contemplates other methods of preventing such premature release, for example, implementing a “cool-down” period of time after power loss before which the latch could not be released. This cool-down period may be implemented by actual thermal cooling of a thermal actuator holding the latch in a locked state or by power reserved, for example, in a capacitor or the like, that may be used in conjunction with a timing mechanism to release the bistable solenoid mechanism  60  by providing a releasing pulse of electricity a fixed period of time after line power is lost. 
         [0064]    The blockade surface  53  may be formed by a thin member that can break away if the lock is forcibly opened by pressing rightward on the trap  40  when the blocking element  54  has descended, such as may occur from a forcible extraction of the striker  26 . When the blockade surface  53  is broken away, a leaf spring  71  positioned on the under surface of the trap  40  is free to move upward and carries with it the blocking element  54 , opening contacts on the lock switch throughout the range of travel of the trap  40 . 
         [0065]    Referring now to  FIGS. 9, 7   a  and  7   b,  the bi-stable mechanism may include an electrical solenoid  62  having a plunger  64  pulled into the solenoid when the solenoid is actuated. The plunger  64  may be surrounded by a helical compression spring  66  that extends the plunger  64  from the solenoid  62  when the solenoid  62  is not actuated. A distal end of the plunger  64  may connect to a pivoting hook  67  guided into alignment with an axis of the plunger  64  when the plunger is fully extended by means of an angled track  68  sloping to an apex spaced from the solenoid  62  and aligned with an axis of the plunger  64 . 
         [0066]    When the solenoid  62  is actuated, the hook  67  is drawn inward and contacts a serrated front surface of a rocking element  70  so that successive energizing of the solenoid  62 , releasing and then pulling in the plunger  64 , causes the rocking element  70  to rock between extremes depicted in  FIGS. 7 a    and  7   b.  A serrated surface of the rocking element  70  guides the hook  67  to pull on opposite sides of the rocking element  70  as it moves from the resting position at the apex of the track  68 , causing this bi-stable motion. 
         [0067]    The rotated extreme, shown in  FIG. 7 b    in a fully clockwise direction, normally provides a locked state for the trap  40 , while the rotated extreme of  FIG. 7 a    in a fully counterclockwise direction normally provides an unlocked state of the trap  40 . 
         [0068]    Referring again to  FIG. 9 , the unlocked state is associated with the wedge element  58  being positioned beneath a sloped portion  59  of the leaf spring  56  to raise the blocking element  54  from engagement with the aperture of the trap  40  (shown in  FIG. 5 ). In contrast, the locked state is associated with the wedge element  58  being removed from the sloped portion  59  of the leaf spring  56 , allowing the blocking element  54  to descend into the aperture of the trap  40 . 
         [0069]    Referring now to  FIGS. 7   a,    7   b,  and  8 , the rocking element  70  may have an anti-vibration tooth  72  extending leftward therefrom to abut an end of the plunger  64  when the solenoid  62  is not being energized and yet is fully extended by helical springs  66 . The anti-vibration tooth  72 , which is positioned abutting opposite sides of the extended plunger  64  for the unlocked state of  FIG. 7 a    and the locked state of  FIG. 7   b,  prevents rotation of the rocking element  70  from vibration alone so long as the solenoid plunger  64  is fully extended. When the solenoid  62  is actuated, however, as shown in  FIG. 8 , a pulling in of the solenoid plunger  64  allows the anti-vibration tooth  72  to slip past the end of the plunger  64  and rotation of the rocking element  70  to occur. 
         [0070]    Referring now to  FIG. 10 , in an alternative embodiment, the hook portion  30  need not be bifurcated (although bifurcation and a ward plate  45  may be used) and the ramp  42  is movable with respect to the stationary structure of the latch  25  to accommodate limited rearward motion under the force from the striker  26  as indicated by arrow  80 . A second rearwardly displaced ramp  42 ′ may be fixed with respect to the stationary structure of the latch  25  ensuring forward movement of the striker  26  as it is inserted into the latch  25  after limited rearward motion of the ramp  42 . Alternatively, a blocking element  73  may be fixed with respect to the stationary structure of a latch  25  to limit the rearward movement of the ramp  42  so that it continues to move the striker  26  forward as required after the limited rearward movement. 
         [0071]    In either case, forward motion of the trap  40  again serves to lock the striker  26  in place and rearward motion of the ramp  42  is used to provide for activation of the anti-tamper feature by moving anti-tamper slide  44 , now communicating with contacts  50 , the latter of which are closed by rearward motion of the ramp  42  indicated by arrow  80 . In this case, motion of the trap  40  to lock the striker  26  and motion of the anti-tamper slide  44  are in opposite directions. Thus, a single probe pressing on leading surface  41  will not be sufficient to activate the latch  25  and activate the anti-tamper switch  50 . 
         [0072]    Referring now to  FIG. 11 , in yet a further alternative embodiment, the ramp  42  is again fixed with respect to the frame of latch  25  per the embodiments of  FIGS. 3 and 4 , and downward motion of the hook portion  30  of the striker  26  causes a bottom surface of the striker  26  to activate a paddle  86  communicating with a rotating axle  88  extending along axis  27  to rotate that axle  88 . The axle  88  may have a tandem paddle  90  activating anti-tamper switch  50  with downward motion of the paddle  86  and rotation of the axle  88 . Thus a single probe pressing on leading surface  41  of the trap  40  will not normally also activate anti-tamper switch  50 . 
         [0073]    In all of the above cases, the striker  26  moves the trap  40  guided by a ramp  42  or  42 ′ on the housing  21 . When the necessary travel of the trap  40  is achieved the portion of the ramp  42  or  42 ′ against the rear of the striker  26  is vertical. Additional travel downward of the striker  26  results in no significant movement of the trap  40 . This has many benefits in the design. One is that at a certain travel of striker  26  downward, the blocking position of the trap  40  is accomplished and allowing blocking . Additional travel of the striker  26  downward does not affect the position two of trap  40 . The force of a lid slam is absorbed by the lid stops (between the lid and the appliance housing), not the structure of the latch  25 . 
         [0074]    In all of the above embodiments, multiple points of physical contact between the hook portion  30  and independent features of the latch  25  are required for activating the latch and indicating that the latch has not been tampered with. 
         [0075]    Generally both activation of switch  50  (corresponding to the anti-tamper slide  44 ) and closure of the lock switch  57  are communicated with the controller board  11  which executes a stored program to prevent operation of the motor  15  unless both lock switch  57  is closed and switch  50  is closed. 
         [0076]    Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “left”, “right”, “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context. 
         [0077]    When introducing elements or features of the present disclosure and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
         [0078]    Various features of the invention are set forth in the following claims. It should be understood that the invention is not limited in its application to the details of construction and arrangements of the components set forth herein. The invention is capable of other embodiments and of being practiced or carried out in various ways. Variations and modifications of the foregoing are within the scope of the present invention. It also being understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention.