Patent Publication Number: US-2022225727-A1

Title: Hands-free Step in Footwear and Method of Use

Description:
CROSS-REFERENCE(S) TO RELATED APPLICATION(S) 
     This application claims benefit of priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 63/138,175 filed Jan. 15, 2021, which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     This application relates to footwear. More specifically, this invention relates to an adaptable insole and heel of footwear and a method of use thereof; with some embodiments of the invention relating to hands-free footwear that require no use of the hands to place the foot into or out of the footwear. 
     BACKGROUND 
     Typically, placing a shoe or other article of footwear onto a person&#39;s foot requires the use of one or both hands, where the person stretches the footwear opening to allow the foot to enter. Without the use of one or both hands, the act of putting on one&#39;s footwear can result in the top of the heel being pushed down or overly loose laces. The heel top often gets damaged over time when pushed down and loose laces require additional time to fasten or a tightening mechanism before the footwear can be effectively used. 
     A desirable solution would be an article of footwear that increases its opening to allow easy entry of a foot while preventing damage to the footwear. Another desirable solution would be a solution that enables automatic tightening and loosing of the laces while the foot is placed in or removed from the footwear. 
     Here is described an article of footwear having an adjustable heel and insole, such that the entry of a foot causes the movement of the insole and heel into a closed configuration. Further, an easy to use mechanism is provided to enable the foot to be removed, using simple force to place the heel in an open configuration. In some cases, the footwear also has an automatic tightener that secures the foot when the insole and heel are in the closed configuration. 
     SUMMARY 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     One object of the present invention is an article of footwear having an insole, an adjustable heel, a retainer, and releaser. The heel being adjustable with at least an open and closed configuration, the retainer being able to hold the heel in one of those configurations. The retainer has at least two states, a locked state and an unlocked state; the releaser is connected to the retainer and it changes the retainer to the unlocked state. In some cases, the releaser switches between the locked and unlocked state. In some embodiments, the insole responds to force applied to it, and that applied force changes the heel&#39;s configuration. In some embodiments, the insole has a raised and a lowered configuration. In some embodiments, the footwear also has a linker connected to the insole and the heel. The linker transfers the force from the insole to the heel and enables the heel to change configurations. In some embodiments, the heel&#39;s configurations are mechanically linked by said linker. 
     In some embodiments, the mechanical linkage of the linker couples the insole&#39;s raised configuration to the heel&#39;s open configuration and the insole&#39;s lowered configuration to the heel&#39;s closed configuration. In some of these embodiments, the footwear also has an outsole that supports the heel and insole, and an upper connected to the outsole. Here, the upper and outsole form a first enclosure for a portion of a foot, and the heel in its closed configuration and the outsole form a second enclosure. The second enclosure is for a second portion of the foot and secures the foot into the footwear. In some of these cases, the heel&#39;s open configuration enables movement of a foot into the first enclosure and the heel&#39;s closed configuration prevents movement of the foot from the first enclosure. 
     Another object of the present invention is a way to secure a foot within the footwear having an outsole, an insole, an upper and a tightener. The insole has a raised configuration and a lowered configuration, the upper is connected to the outsole and the tightener is connected to the upper and the insole and has a secure state and a loose state. Furthermore, the insole&#39;s raised configuration places the tightener into the loose state and conversely, the insole&#39;s lowered configuration places the tightener into the secure state. 
     In some embodiments, the footwear disclosed herein has a second linker connected to the insole and the heel. In some embodiments, the releaser is located on the outward facing surface of the heel. In some embodiments, the releaser changes the retainer between its locked and unlocked state. In some cases, the insole is a single, unbroken piece. In some embodiments, the footwear has the outsole that supports the heel and insole, and the insole is prevented from having a configuration that moves or otherwise adjusts below the plane of the outsole. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In what follows, preferred embodiments of the invention are explained in more detail with reference to the drawings, in which: 
         FIGS. 1A and 1B  are two side views of a footwear article according to one embodiment.  FIG. 1A  shows the footwear in the open configuration with loose tightener laces, and  FIG. 1B  shows the footwear in the closed configuration with tight tightener laces. 
         FIGS. 2A-2C  are three bottom views of three embodiments according to the present invention. 
         FIGS. 3A and 3B  illustrate the adjustable heel according to two embodiments of the present invention, with the open configuration in solid lines and the closed configuration in broken, dashed lines. 
         FIGS. 4A and 4B  are two possible heels according to the present invention with anchor points and linker structure illustrated. 
     
    
    
     DEFINITIONS 
     The term “anchor” as used herein refers to a point or area on a footwear component, typically the heel or insole, that connects to another component (e.g., the linker). 
     As used herein, the term “major axis” refers to the axis that runs the length of the footwear from the heel to the toe. The term “minor axis” refers to the axis perpendicular to the major axis, running from one lateral side of the footwear to the other. 
     DETAILED DESCRIPTION 
     Overview 
     The present disclosure describes an article of footwear  100  with an adjustable heel  109  to easily allow entry and exit of a user&#39;s foot and is shown in  FIGS. 1A-4B . Generally, the footwear  100  has an upper  101 , a sole  102 , and a heel  109 ; the sole  102  having an insole  103  and at least an outsole  119 . The heel  109  is adjustable and has at least two configurations, open and closed. The heels&#39; open configuration  109   a  enables the entry and exit of a user&#39;s foot into the footwear, and the heel&#39;s closed configuration  109   b  enables the user&#39;s foot to be securely fixed within the footwear  100 . A retaining mechanism  107  attached to or located within the heel  109  provides a means for maintaining the heel  109  in a configuration. A release mechanism  108  enables the disengagement of the retaining mechanism  107 , thus enabling the heel  109  to change between configurations. 
     In the currently preferred embodiment, the insole has at least two configurations, raised  103   a  and lowered  103   b , as illustrated in  FIGS. 1A and 1B , respectively. Typically, the configurations of the insole  103  are physically linked to the configurations of the heel  109 , for example, the heel&#39;s open configuration  109   a  is physically linked to the insole&#39;s raised configuration  103   a . Pressure, often downward, on the insole&#39;s raised configuration  103   a  drives the insole  103  to change to the lowered configuration and the linked heel to change to the closed configuration  109   b . The linkage between insole and heel is provided by a linker  106 . 
     Further embodiments of the present disclosure provide articles of footwear  100  with a tightener  110  that automatically loosens and tightens as the footwear  100  is placed into the open and closed configurations, respectively, as illustrated in  FIGS. 1A and 1B . The insole raised configuration  103   a  enables the connected tightener  110  to loosen the upper  101 , allowing easy exit and entry of a user&#39;s foot into the footwear  100 . When the insole  103  in placed into the lowered configuration  103   b , most often by closure of the heel  109 , the insole  103  typically moves physically lower, pulling, and therefore tightening the tightener  110 . Because this single motion causes both heel closure and upper tightening, no additional tightening of the footwear is required, simplifying use, and aiding in persons with limitations. 
     Upper 
     The present disclosure provides for a footwear upper  101  section that restrains a foot in place in the footwear  100 , the upper  101  section is referred herein as the upper and the footwear sole  102  section referred herein as the sole. The upper  101  and heel  109  are connected to or otherwise mounted onto the sole  102 . The heel  109  and upper  101  may be physical attached to one another or may be physically separate pieces. When attached, they are preferably linked with a flexible or stretchable connection, e.g., an elastic fabric. The upper  101  secures or encloses a forward portion of a user&#39;s foot, while the heel  109  secures or encloses the user&#39;s heel. The upper  101  comprises a tightening system (e.g., laces) to hold the foot properly within the footwear. 
     Sole 
     The present disclosure provides for a footwear sole  102  that supports the bottom of the foot and connects the upper  101 . The sole  102  comprises an insole  103 , an outsole  119 , and optionally, a midsole  124 . In the currently preferred embodiment, the outsole  119  is a single piece, typically flexible, but not hinged or substantially separatable from itself. The insole  103  is adaptable and may adopt multiple configurations to enable foot entry and exit. The footwear may be thought of as having two axes; a major axis  118  of the footwear runs from the heel to the toe box and a minor axis  123  perpendicular to the major axis, as illustrated in  FIG. 2C . 
     The outsole  119  physically supports the remainder of the footwear  100 . The outsole  119  supports the heel  109 , the insole  102 , and the upper  101  and is most often permanently attached to the heel  109  and upper  101 . Together the upper  101 , heel  109 , and outsole  119  can be thought of as forming an enclosure for the foot. Because the heel  109  is adaptable, the foot enclosure is broken into a first, forward enclosure and a second, rearward enclosure. The forward enclosure is formed by the outsole  119  and upper  101  and encloses the forward portion of a user&#39;s foot. The rearward enclosure is formed by the outsole  119  and the heel  109  and encloses the rearward portion of a user&#39;s foot (i.e., the heel and, in some cases, the ankle). 
     In the currently preferred embodiment, the outsole  119  (and midsole  124 , if present) are one physical piece that does not open in any manner, for example hinged or otherwise articulated as two sections. Known in the art are shoes with increased ease of access that have two articulating outsole sections. These shoes have structural deficiencies due to the broken outsole and midsole sections, which are responsible for receiving the majority of the foot&#39;s pressure onto the shoe. The present disclosure presents an increased ease of access footwear  100  without sacrificing midsole  124  and outsole  119  durability. In some embodiments, the heel  109  is prevented from adopting a configuration that puts the heel  109  below the plane of the outsole  119 . The plane of the outsole  119  may be described as the midpoint or midline between the top and bottom of the outsole, as illustrated by dash-dotted line  121  in  FIG. 4B . 
     Insole 
     The present disclosure provides for an insole  103  that supports the foot. The insole  103  is within the footwear&#39;s sole section  102  and most often rests on top of the outsole  119  and midsole  124 , if present. The insole  103  is connected to a linker  106 . In the currently preferred embodiment, the insole  103  has at least two configurations, a raised configuration  103   a , and a lowered configuration  103   b . When in its raised configuration  103   a , the insole  103  is partially raised above its supporting structure (e.g., the outsole  119 ); typically, only the rearward portion (towards the heel) is raised, and the forward portion (towards the toe box) is resting on the supporting structure. The insole  103  rests fully, or rests substantially, on its supporting structure when in its lowered configuration  103   b . An applied force, often downward pressure, onto the insole&#39;s raised configuration  103   a  causes the insole  103  to adjust into its lowered configuration  103   b ; the connected linker  106  then translates that force to the heel  109 , causing an adjustment from the heel&#39;s open configuration  109   a  to the closed configuration  109   b . In some embodiments, the insole  103  moves in relation to the outsole  119  when changed from the open to the closed configuration. Most often the insole  103  movement is forward (towards the toe box), further enabling the linker&#39;s adjustment of the heel from the open  109   a  to the closed configuration  109   b.    
     In the currently preferred embodiment, the insole  103  spans the entire length of the outsole  119  or substantially the length of the outsole  119 . In most embodiments, the insole  103  is a single physical piece that spans, or physically runs substantially the length of the footwear  100  in at least one configuration. In some embodiments, the insole  103  spans 75% of the length of the sole  102  (or outsole  119 ). In other embodiments, the insole  103  spans 90% of the length of the sole  102  (or outsole  119 ). 
     Heel 
     The present disclosure provides for an adaptable heel  109  enabling entry and exit of a user&#39;s foot as well as a secure and fixed structure around the rear of a user&#39;s foot when the foot is inside the footwear  100 . The heel  109  moves, deforms, adjusts, or otherwise adapts between at least an open configuration  109   a  and a closed configuration  109   b . Each configuration serves a function of the footwear. The open configuration  109   a  enables movement of a user&#39;s foot into and out of the footwear  100  and the closed configuration  190   b  prevents movement of a user&#39;s foot into or out of the footwear  100 . Said another way, the open configuration  109   a  allow access to the forward enclosure, while the closed configuration  190   b  prevents access to the forward enclosure. Often, the heel  109  is connected to the linker  106  that connects the heel  109  to the insole  103 . The linker  106  provides the physical link between insole  103  and heel  109  configurations, enabling the adjustment of the heel  109  when the insole  103  is adjusted by a user; as well as the opposite, the adjustment of the insole  103  when the heel  109  is adjusted by a user. Typically, the heel  109  is connected to the retainer  107  that prevents the heel  109  from adjusting between configurations. 
     Heel Configurations. The heel  109  has at least two configurations, an open configuration  109   a , and a closed configuration  109   b , illustrated in  FIGS. 1A and 1B . Two additional views of open configurations  109   a  are illustrated in  FIGS. 3A and 3B . The open configuration  109   a  enables easy access by a user to place their foot into the footwear  100 . The closed configuration  109   b  enables a secure fit of the footwear  100  around the user&#39;s foot when inside the footwear  100 . In the currently preferred embodiment, opening the heel  109  physically (e.g., by a user&#39;s hand) places the insole  103  into its raised configuration  103   a . Pressure onto the insole&#39;s raised configuration  103   a  drives the insole  103  into its lowered configuration  103   b  and the heel into its closed configuration  109   b . The heel  109  may also be physically placed into its closed configuration  109   b  by an external force (e.g., a user&#39;s hand closing the heel  109  in an empty footwear  100 ). 
     It is within the scope of the present invention for the heel  109  to have additional configurations, for example a storage configuration that adjusts the heel  109  to obscure or close the footwear&#39;s ankle opening substantially or partially. In other words, the storage configuration is substantially in contact with the lateral and top edges of the upper. Another possible configuration comprises a cleaning configuration, wherein the heel  109  is adjusted to a larger opening than the open configuration  109   a , enabling easy access to the footwear interior, often for the purpose of cleaning the footwear&#39;s interior. In some embodiments, the heel  109  is prevented from assuming a configuration that brings the heel substantially below the plane of the outsole. 
     The heel  109  may be either connected to or separate from the upper  101 . When the heel  109  is connected to the upper  101 , the connection is most often elastic or otherwise deformable, such that the fabric or other material joining the heel  109  and upper  101  stretches or deforms, allowing the heel  109  to change between configurations. When the heel  109  is not connected to the upper  101 , the heel  109  touches or comes in close proximity to the upper  101  when in the closed configuration  109   b , forming a footwear  100  with substantially no openings on the lateral faces of the footwear  100 . In other embodiments, for example sandal footwear  100 , the heel in the closed configuration  109   b  has opening on the lateral faces of the footwear  100 , often substantial openings, between the heel  109  and any upper  101 . 
     Linker 
     The present disclosure provides a mechanism to connect and translate forces between insole  103  and heel  109 , referred herein as the linker  106 . Most often, the connection is mechanical. In some cases, the linker  106  connection may be magnetic or in rare cases electromagnetic. The linker  106  serves to link the insole&#39;s raised configuration  103   a  with the heel&#39;s open configuration  109   a  and to link the insole&#39;s lowered configuration  103   b  with the heel&#39;s closed configuration  109   b . In some embodiments the linker  106  is a hinge, as illustrated in  FIGS. 1A and 3A . In some embodiments the linker  106  comprises a track or rail means  115  that enables an articulating linker  116  arm or rod to adjust the configuration of the heel  109 . 
     The linker  106  may be attached to the heel  109  and insole  103  by any suitable means known in the art. In one embodiment, the linker  106  is made of a durable plastic, and is fastened (e.g., glued) to a portion of the heel  109  at one end of the linker  106  and fastened (e.g., glued) to a portion of the insole  103  at the other end of the linker  106 . The portion of the heel  109  to which the linker  106  is attached is referred herein as the heel anchor  113  and, similarly, the portion of the heel to which the linker is attached is referred herein as the insole anchor  112 . In other embodiments the linker  106  is a metal strip, sometimes surrounded by a layer of fabric, that is fastened to the heel anchor  113  and the insole anchor  112 . Suitable fasteners include glue, screws, bolts, welding, and the like. In some embodiments the linker  106  is one physical piece with another component, for example a one-piece heel  109  and linker  106 . In some cases, the linker  106  is a single physical piece located underneath the insole  103 , connecting to an insole anchor  112  that is located on the underside face of the insole  103 . In these cases, the outsole  119 , or midsole  124 , if present, has a groove  114  that accepts the linker  106  such that the insole  103  rests evenly (i.e., substantially flat) on the component below it (e.g., outsole  119 ), as illustrated in  FIG. 2A . 
     In some embodiments, the linker  106 T has an approximately triangular shape, shown in  FIG. 4A , connecting to the insole  103  at one insole anchor point A 1 , and to the heel  109  at two heel anchor points C 1  and C 2 . In other embodiments, the linker  106 R is approximately rectangular, connecting to the insole  103  at two or more insole anchor points, illustrated as points A 3  and A 4  in  FIG. 4B  and to the heel  109  at two or more heel anchor points C 3  and C 4 . Of note, the plane of the insole is shown in  FIGS. 4A and 4B  as a dashed line  103  and is overlapping with the linker structure (solid black line). The groove  114  may further comprise structure that aids linker  106  movement, for example, runners, a low-friction surface, or miniature bearings. In other cases, the linker  106  is two physical pieces, disposed on either side of the insole  103 , each linker piece connecting to separate insole anchors, and to separate heel anchors. One example of this is shown in  FIG. 2C , where two linkers, linker  116  and  117 , each separately connect to heel anchors B 1  and B 2 , respectively. Typically, each insole anchor  112  would be equal distant along the minor axis  123  of the insole  103 . In still other cases, the linker  106  is three physical pieces, having one linker  106  underneath the insole  103  and two on either side of the insole  103 , as described above. 
     Retainer and Releaser 
     A mechanism for keeping the heel  109  in one configuration is provided, referred herein as the retainer  107 . A mechanism for releasing the retainer is also provided, referred herein as the releaser  108 . The retainer  107  has at least two states, an unlocked state, and a locked state. The unlocked state has no effect on the adjustment of the heel  109  between heel configurations, while the retainer&#39;s locked state holds, locks, or otherwise prevents a change in heel configuration. For example, and most typical, in its locked state, the retainer  107  prevents the heel  109  to adjust from the closed configuration  109   b  to the open configuration  109   a . It is within the scope of this disclosure for the retainer&#39;s locked state to prevent the heel  109  to adjust between other configurations (e.g., locking the heel  109  in the storage configuration). 
     Releaser  108  is connected to at least the retainer  107  and is configured to change the retainer&#39;s state. Typically, the releaser  108  comprises a button or other activation mechanism (e.g., a switch) connected to a mechanism to interact with the retainer  107 . Typically, the releaser  108  is activatable by a user, often by the user&#39;s other foot that is not in the article of footwear  100 . The releaser  108  is most often on the heel&#39;s outward facing surfacep, away from the article of footwear  100 , as illustrated in  FIG. 3B . The retainer  107  and releaser  108  may be any suitable locking and releasing mechanisms as known in the art. Most often the retainer  107  and releaser  108  are mechanical mechanisms. In less preferred embodiments, one or both the retainer  107  and releaser  108  are magnetic mechanisms. In one embodiment, the retainer  107  comprises one or more stop members attached to a cam, as known in the art. The stop members are accepted into releaser slots and when so positioned in the releaser slots; changing of the heel configuration is prevented. Activation of the releaser ejects the stop members from the releaser slots, the cam moves (e.g., rotates) the stop members into a position that prevents the stop members from entering the releaser slots, and the retainer is changed into the unlocked state. 
     In other embodiments, the retainer  107  is released by the releaser  108  by pressing on the heel  109  farther forward, towards the heel  109 , while the heel is in the closed configuration  109   b . This farther forward motion presses the user&#39;s foot into the forward section of the footwear  100 , but also releases a stop from the retainer  107 , allowing the heel  109  to adjust into the open configuration. Once in the open configuration  109   a  the retainer stop is reset, allowing the retainer stop to again engage the retainer  107  when again placed into the closed configuration. 
     Tightener 
     The present disclosure provides for a mechanism to tighten and loosen the upper  101  to secure a user&#39;s foot in the footwear  100 , referred herein as the tightener  110 . The tightener  110  may be any suitable mechanism as known in the art. The tightener  110  has at least two states, a loose state  110   a , and a secure state  110   b . The loose state  110   a  enables entry or exit of the foot into the footwear  100  and the secure state  110   b  prevents movement of the foot while in the footwear  100 . In one embodiment, the footwear  100  has a crisscrossing lace secured to lace eyelets  122  sewn, fastened, or otherwise incorporated into the upper  101 . The tightener  110  comprises multiple connections between each lace eyelet  122  and to the insole  103 . The insole&#39;s lowered configuration  103   b  stretches the tightener, pulling down the lace eyelets  122  and the upper  101  structure down around the foot, tightening the footwear  100 . In another embodiment the tightener  110  comprises one or more pieces of fabric fastened to either side of the sole  103  running the length of the minor axis  123  and over a user&#39;s foot in the upper  101 , and typically secured to the insole  103 . The fabric tightener  110  typically has at least some elasticity, stretching to allow entry of the foot, but when relaxed, resuming a tight configuration to secure the foot within the footwear  100 . 
     Automatic Tightening 
     It is within the scope of the present disclosure for some embodiments to have a mechanism for automatically tightening and loosen the tightener  110 . Automatic tightening further enables a quick and hands-free entry and exit of a user&#39;s foot into and out of the footwear  100 . The automatic tightening may be any suitable system as known in the art. Generally, the tightener&#39;s tight state  110   b  secures a user&#39;s foot inside the footwear  100  and the loose state  110   a  allows a user&#39;s foot to enter or exit the footwear  100 . It is possible for the tightener  110  to have additional states. Typically, the tightener  110  state is linked to the insole  103  configuration. Typically, the insole&#39;s raised configuration  103   a  places the tightener into its loose state  110   a  and the insole&#39;s lowered configuration  103   b  places the tightener into its secure state  110   b.    
     In one embodiment, the tightener  110  comprises a fabric tightener attached to two sides of the insole  103 , such that when the insole is in the raised configuration  103   a  the tightener  110  is loosened away from the upper  101  and a user&#39;s foot, enabling entry and exit of the foot. When the insole is placed into the lowered configuration  103   b  (often by a user placing their foot into the footwear  100 ), the tightener  110  is pulled down along with the insole  103  and tightened against the upper  101  and the user&#39;s foot. In more embodiments, the tightener  110  is comprises a spring coil (fabric or metal) that connects to the insole  103 . The coil is affected by the configuration of the insole  103 , adjusting as the insole adjusts. Often this adjustment comprises increasing or decreasing in length. In one embodiment, the coil is held coiled when the insole is in the lowered configuration  103   b , decreasing its length and automatically tightening the tightener  110 . In this embodiment, when the insole is in the raised configuration  103   a , the coil is released and increases in length, automatically loosening the upper  101 . These tighteners  110  may be held in place by a suitable mechanism or structure on the outsole  119  or midsole, if present. 
     Example 
     One exemplary embodiment will be presently described. An article of footwear  100  comprising an upper  101  made of a woven fabric of polyester backing adhered to a leather outer layer is glued to an outsole  119  made up of polyurethane. The linker  106  extends through a shallow groove  114  shaped into the top surface of the outsole  119  and is connected to the heel  109  at the heel anchor  113 . The heel  109  is attached to the outsole  119  such that the heel pivots away from the upper  101 , with the heel anchor  113  serving as the pivot point. Heel  109  and upper  101  are made of the same material and are connected to each other by an elastic woven polyester fiber, preferably the same color or color scheme as the upper  101  and heel  109 . 
     The heel  109  further comprises a releaser  108  button situated in the middle of the back face of the heel  109 . The releaser  108  button is made of a circular soft plastic pushbutton switch surrounded by a hard plastic rim around the switch&#39;s circumference. Pressure on the pushbutton switch releases the retainer  107  and places the footwear  100  into the open configuration. Pressure on the heel  109  itself moves the heel into contact with the upper  101 , moves the insole  103  down, and locks the heel  109  into its closed configuration  109   b  and insole  103  into the lowered configuration  103   b.    
     The footwear  100  further has a tightener  110  made of a synthetic fiber, e.g., spun polyester laces. The tightener  110  laces are attached to the insole  103  and threaded either through openings in the upper  101  or attached to a lace eyelet  122 . The tightener  110  is put into its loose state  110   a  when the heel  109  is in its open configuration  109   a  and the insole  103  is in its raised configuration  103   a . When the insole  103  is pressed down and placed into its lowered configuration  103   b , the tightener  110  is physically pulled lower and automatically placed into its secure state  110   b.    
     Although specific features of the present invention are shown in some drawings and not in others, this is for convenience only, as each feature may be combined with any or all of the other features in accordance with the invention. While there have been shown, described, and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions, substitutions, and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit and scope of the invention. For example, it is expressly intended that all combinations of those elements and/or steps that perform substantially the same function, in substantially the same way, to achieve the same results be within the scope of the invention. Substitutions of elements from one described embodiment to another are also fully intended and contemplated. It is also to be understood that the drawings are not necessarily drawn to scale, but that they are merely conceptual in nature. 
     It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto. Other embodiments will occur to those skilled in the art and are within the following claims.