Patent Publication Number: US-7900378-B1

Title: Low profile deflation mechanism for an inflatable bladder

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to a low profile deflation mechanism for use with an inflatable bladder, preferably an inflatable bladder for an article of footwear. 
     BACKGROUND OF THE INVENTION 
     Fit, comfort and cushioning are desired features in footwear. Inflatable bladders have been used in articles of footwear, or shoes, to provide improved fit and cushioning for better comfort. The inflatable bladder may form part of either the shoe upper or the sole of a shoe and may be inflated by a variety of inflation mechanisms, including a detachable inflation device, an on-board inflation device, an automatic underfoot inflation device, etc. 
     One goal in developing inflatable bladders for shoes has been to control the volume and pressure of air within the bladder. Too little air or too little air pressure within an inflatable bladder may not provide sufficient fit and/or cushioning to the shoe, such that the shoe may be loose or may not provide adequate cushioning. Too much air or too high of air pressure within an inflatable bladder may cause the bladder to pinch or exert painful pressure to areas of the foot during athletic activity. Thus, various deflation mechanisms and pressure regulators have been provided to control the air pressure within the inflatable bladder. 
     U.S. Pat. No. 6,785,985 and Published U.S. Patent Application Numbers 2004/0003517 and 2005/0028404, each of which is incorporated by reference herein in its entirety, describe, inter alia, various deflation mechanisms for controlling the amount of air within an inflatable bladder. 
     Another goal in shoe design is to provide an article of footwear with a low profile. As such, large and cumbersome features extending from an exterior surface of a shoe add weight to the shoe and are generally less aesthetically pleasing to the eye. Further, extending features may become hit, brushed against or damaged and may be hazardous to other participants during athletic activity, for example contact sports. 
     Another goal in designing shoe parts is ease of use. Inflation or deflation mechanisms which are difficult to use are not desirable. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides low profile and easy to use knobs for an article of footwear. 
     One embodiment of the present invention is an article of footwear including a movable knob and a lever coupled to the knob. The movable knob is accessible from an exterior surface of the article of footwear and has a substantially low profile with respect to the exterior surface of the article of footwear. The lever has a first position in which the lever lays flat against the knob and a second position wherein the lever is positioned for a user to move the knob via the lever. When not in use assisting with the movement of a knob, the lever lays flat against the knob maintaining a low profile with respect to the exterior of the article of footwear. 
     Another embodiment of the present invention is an article of footwear including an inflatable bladder, an inflation mechanism fluidly connected to the inflatable bladder and a deflation mechanism fluidly connected to the inflatable bladder. The deflation mechanism includes a cap and a base, in which the cap is rotatable with respect to the base. The cap includes a lever that has a first position in which the lever lays flat against an upper surface of the cap and a second position wherein the lever extends perpendicular from the upper surface of said cap. The lever is hingedly moveable between the first and second positions. 
     In another embodiment of the present invention, an article of footwear includes a movable knob accessible from an exterior surface of the article of footwear and an apron substantially surrounding the movable knob. The apron includes ramped sides and provides a substantially low profile to the knob with respect to the exterior surface of the article of footwear. The apron effectively reduces the profile of the deflation mechanism to protect the deflation mechanism during athletic activities. 
     Further embodiments, features, and advantages of the present invention, as well as the structure and operation of the various embodiments of the present invention, are described in detail below with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES 
       The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention. 
         FIG. 1A  is a perspective view of an embodiment of the present invention positioned on an article of footwear with the lever in the “down” position.  FIG. 1B  is a perspective view of the embodiment of  FIG. 1A  with the lever in the “up” position. 
         FIG. 2A  is a perspective view of an embodiment of a valve of the present invention with the lever in the “down” position.  FIG. 2B  is a perspective view of the embodiment of  FIG. 2A  with the lever in the “up” position.  FIG. 2C  is a top view of the embodiment of  FIG. 2A . 
         FIG. 3A  is a schematic exploded sectional view of the components of an embodiment of a valve of the present invention.  FIG. 3B  is a schematic sectional view of the components of  FIG. 3A . 
         FIG. 4  is a schematic top view of an embodiment of a valve of the present invention. 
         FIG. 5A  is a perspective view of an embodiment of a valve of the present invention.  FIG. 5B  is a sectional view of the valve of  FIG. 5A .  FIG. 5C  is a sectional view of an embodiment of a valve of the present invention. 
         FIG. 6A  is a side view of an alternative embodiment of an article of footwear of the present invention.  FIG. 6B  is a side view of an embodiment of a valve of the present invention.  FIG. 6C  is a perspective view of the valve of  FIG. 6B .  FIG. 6D  is a top view of the valve of  FIG. 6B .  FIG. 6E  is a side view of the valve of  FIG. 6B  in an open position.  FIG. 6F  is a side view of the valve of  FIG. 6B  in an open position wherein the valve is at a different setting. 
     
    
    
     The present invention will be described with reference to the accompanying drawings. The drawing in which an element first appears is typically indicated by the leftmost digit(s) in the corresponding reference number. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is directed to a deflation mechanism for an inflatable bladder having a low profile. Preferably, the present invention provides a low profile deflation mechanism that is particularly useful for an inflatable bladder of an article of footwear. 
       FIGS. 1A and 1B  illustrate such an article of footwear, or shoe  100 . Shoe  100  includes an inflatable bladder (not shown). A variety of inflatable bladders may be utilized in the present invention. For example, any of the inflatable bladders described in U.S. Pat. No. 6,785,985 and Published U.S. Patent Application Numbers 2004/0003517 and 2005/0028404 may be suitable for use in a shoe of the present invention. One skilled in the art can appreciate that the type of inflatable bladder for use in the present invention is not limited. One example of an inflatable bladder includes two sheets of sealable thermoplastic material through which air may not readily pass. These sheets are sealed around a periphery to form an inflatable bladder. The inflatable bladder preferably includes an inflation mechanism  700  (see  FIG. 3A ) and a deflation mechanism fluidly connected thereto to customize the pressure and air volume within the inflatable bladder. The present invention is particularly suited for an on-board underfoot inflation mechanism that is operated by the downward pressure of a wearer&#39;s foot. Such an inflation mechanism constantly forces air pressure into the inflatable bladder, and thus the inflatable bladder may become too pressurize and uncomfortable. A preferred deflation mechanism is one that maintains a consistent pressure within the inflatable bladder, and more preferably is adjustable. 
     Shoe  100  includes a knob  102 . Shoe  100  further includes an apron  104 , also referred to as a berm, that surrounds knob  102 . Apron  104  has a gradually ramped sidewall that provides a low profile and protects knob  102 , such that it will not get knocked, brushed or damaged during athletic activity. Knob  102  may be moved, for example by turning. However, given the low profile of knob  102 , that for example is created by apron  104 , it will be difficult to access the knob  102  to move it. One solution to this problem is to have apron  104  be temporarily removable from knob  102 , such as being flipped away from knob  102  as discussed below with respect to  FIGS. 6A-6F . Another solution is to have knob  102  provided with a lever  108 . Lever  108  is illustrated in  FIG. 1A  in a “down” position, such that when not in use the lever contributes to the low profile of the knob  102 . In the “down” position, lever  108  is generally flat against or adjacent to an upper surface  117  of knob  102 .  FIG. 1B , however, illustrates how lever  108  may be raised to an “up” position, such that a user may grasp lever  108  to move knob  102 . In the “up” position, lever  108  is generally perpendicular to or extends from upper surface  117  of knob  102 . Further, apron  104  may provide a location for indicators  110 . Since knob  102  moves with respect to apron  104 , indicators on apron  104  identify the amount that the cap has been turned. 
     Knob  102  may be found on any part of an article of footwear, for example anywhere on a sole  105  or upper  103  of shoe  100 . 
     In an alternative embodiment, knob  102  may have a profile for other reasons. For example, knob  102  may be flush with an exterior surface of shoe  100 , such that an apron  104  is not necessary. In this case, in order to move knob  102 , lever  108  must be moved to the “up” position. Alternatively, apron  104  may be replaced or covered by upper or sole material adjacent to knob  102  to provide the desired low profile. Sole or upper material may be foam padding or other cushioning material to further protect the area around knob  102 . 
     In an alternative embodiment, knob  102  may turn, slide, be removable or function in another manner apparent to one skilled in the art such that a low profile may make it difficult to move knob  102 . As such, a lever  108  coupled to knob  102  provides for ease of movement of knob  102  and folds to a “down” position to maintain the low profile of knob  102 . 
     A deflation mechanism  202  is illustrated in  FIGS. 2A-2C . Deflation mechanism  202  includes a base  212 , a cap  206 , which rotates with respect to base  212 , and a lever  208 . Thus, cap  206  functions as a movable knob. In the present invention, lever  208  includes a hole  214  which engages a pin  216  extending from an upper surface  217  of cap  206  when lever  208  is in a “down” position. As illustrated below, cap  206  is snap fit onto base  212 . Similarly, lever  208  includes first and second prongs (not shown) that fit into recesses in cap  206  generally at areas  219  to allow for hinged movement of lever  208  about an axis, which is schematically illustrated as axis  220  in  FIG. 2C .  FIGS. 2A and 2B  illustrate this hinged movement. 
     Each of cap  206 , base  212  and lever  208  may be separately molded pieces. Preferably, cap  206  and/or lever  208  may be made of a durable plastic material. Base  212  may be made of a similar durable plastic material, or it may be made of a sturdy but more flexible plastic material so as to flex along with any flexible material that comprises the shoe, for example the material that comprises the upper of the shoe. An apron, such as apron  104  of  FIGS. 1A and 1B , may be used with deflation mechanism  202  and may be made of a similar durable plastic material to that of cap  206  and/or lever  208 . Lower costs make injection molded parts preferable. However, lever  208 , cap  206 , base  212  and apron  104  may be made from metal, such as die-cast aluminum, hardened foam or any other material that would be apparent to one skilled in the art. 
       FIG. 3A  is a schematic exploded view of components of a deflation mechanism  302  of the present invention. Deflation mechanism  302  includes an apron  304 , a lever  308 , an upper cap piece  322 , a lower cap piece  324  and a base  312 . Upper cap piece  322  and lower cap piece  324  fit together to form a cap  306  which rotates with respect to base  312 . In other embodiments, however, upper cap piece  322  may be formed with lower cap piece  324  in a single piece. 
     Deflation mechanism  302  is fluidly connected to an inflatable bladder  330  comprising a first sheet  332  and a second sheet  333  of material that is generally fluid impervious, such as a thermoplastic or other material conventionally used to form inflatable bladders for articles of footwear. Base  312  includes a seating  326  having an inlet  328  therein. Inlet  328  is fluidly connected to inflatable bladder  330  via a hole  331  in first sheet  332 . A lower surface  312   a  of base  312  may be sealed to an upper surface  332   a  of first sheet  332 , for example, by gluing, bonding, radio frequency (RF) welding, heat welding, ultrasonic welding, or another other method known to one skilled in the art. Alternatively, an upper surface  312   b  of base  312  may be sealed to a lower surface  332   b  of sheet  322 , such that a substantial portion of base  312  extends through hole  331  in first sheet  332 . 
     A one-way valve  334  is seated in inlet  328  to limit the flow of air from inflatable bladder  330  to the environment. In the example of  FIGS. 3A and 3B , one-way valve  334  is an umbrella valve, such as the type typically available from Vernay Laboratories, Yellow Springs, Ohio. One-way valve  334  includes a flange  334   a  which forms a seal with seating  326 . When the pressure within bladder causes the pressure under flange  334   a  to reach a predetermined pressure, flange  334   a  lifts off of seating  326  allowing air to escape from inflatable bladder. 
     Extending from lower surface  312   a  of base  312  is a ring  335  having a wavy exterior surface. Ring  335  prevents second sheet  333  of inflatable bladder  330  from collapsing against inlet  328 , which would cause one-way valve  334  to cease operating properly. Ring  335  also provides an optional filter  336  to be positioned adjacent one-way valve  334  by having a filter cover  337  press fit against ring  335 . Filter cover  337  holds filter  336  in place. Filter  336  stops impurities within bladder  330  from getting under flange  334   a  and inhibiting the seal between flange  334   a  and seating  326 . 
     Base  312  also includes a generally cylindrical wall  312   c . A portion of wall  312   c  includes a shoulder  312   d  that defines a channel  312   e . Shoulder  312   d  is provided to ensure cap  306  is securely fitted with base  312 . Channel  312   e  is provided as a track for the rotational movement of cap  306  with respect to base  312 . Base  312  also includes a projection  312   f  which temporarily snaps into notches on cap  306  to let the user know when the rotation of cap  306  has reached its limits. 
     Lower cap piece  324  includes an upper wall  324   a  and a generally cylindrical sidewall  324   b  extending from upper wall  324   a . Sidewall  324  includes at least one extended edge  324   c . As illustrated in  FIG. 3B , extended edge  324   c  locks over shoulder  312   d  of base  312  to keep cap  306  and base  312  together. Extended edge  324   c  also slides within channel  312   e  allowing cap  306  to rotate with respect to base  312 . Lower cap piece  324  also includes notches  324   g  which engage projection  312   f  of base  312  as cap  306  rotates with respect to base  312 . 
     Upper wall  324   a  includes an opening  324   d  and a mushroom-shaped protrusion  324   e , each of which allows lower cap piece  324  to snap fit and lock with upper cap piece  322 , as discussed in detail below. Upper wall  324   a  also includes a curved extension  324   f . Curved extension  324   f  has a flat side  324   f  and a curved side  324   f ″. As illustrated in  FIG. 3B , curved extension  324   f  is a seat for lever  308 . The curved side  324   f ″ of curved extension  324   f  cradles lever  308  and the flat side  324   f  allows lever  308  to lie flat when in a “down” position. 
     Upper cap piece  322  has a lower surface  322   a  from which extends a cylindrical projection  322   b . Projection  322   b  includes a shoulder  322   c . As shown in  FIG. 3B , projection  322   b  extends through opening  324   d  in lower cap piece  324 . Also, upper cap piece  322  has a hole (not shown) through which mushroom-shaped protrusion  324   e  of lower cap piece  324  extends when lower cap piece  324  and upper cap piece  322  are placed together. The head of mushroom-shaped protrusion  324   e  and the shoulder  322   c  of projection  322   b  ensure that, once snapped together, lower cap piece  324  and upper cap piece  322  will not be separated. Additionally, upper cap piece  324  and lower cap piece  322  may be affixed by gluing, bonding or another method apparent to one skilled in the art. 
     Upper cap piece  322  includes two recesses  322   d  which engage prongs  308   a  extending from opposite sides of lever  308 . Lever  308  is hingedly movable about prongs  308   a  from the “down” position to the “up” position. A wall  322   e  in upper cap piece  322  is provided to give lever  308  something to push against to turn cap  306 . Additionally, wall  322   e  keeps lever  308  extended when in an “up” position so that lever  308  does not fall flat in two directions. Upper cap piece  322  also includes a pin  316  extending from an upper surface  317  of cap  306 . Pin  316  engages a hole, such as hole  214 , in lever  308  when lever  308  is in a “down” position. 
     As shown in  FIG. 3A , apron  304  is cylindrical-shaped with a ramped sidewall  304   b . Indicators, such as indicators  110 , may be printed or otherwise provided on the surface of ramped sidewalls  304   b . In an optional embodiment, apron  304  may have a cut out section  304   a  (illustrated in phantom) which may be provided to help the user access lever  308  in its “down” position. As illustrated in  FIG. 3B , apron  304  surrounds deflation mechanism  302 . 
       FIG. 3B  shows the construction of apron  304  and deflation mechanism  302 . Although optional,  FIG. 3B  includes, for illustrative purposes only, additional upper or sole material  338  positioned between inflatable bladder  330  and apron  304 . In other embodiments, additional material  338  may be sewn, sealed or otherwise fixedly attached to a first sheet  332  or second sheet  333  of inflatable bladder  330 , to upper or lower surfaces  312   a  or  312   b  of base  312  or to apron  304 . Material  338  may be for cushioning and comfort, such as foam padding or midsole material, or it may be exterior upper material. Similarly, first sheet  332  may be formed from a laminate of a plastic material and a substrate. 
     Deflation mechanism  302  functions by rotating cap  306  from an “auto” position, as shown in  FIG. 3B , to an “off” position. In the “auto” position, one-way valve  334  is allowed to selectively release air from inflatable bladder  330  when the pressure reaches a predetermined pressure. In the “off” position (not shown), cap  306  is rotated such that projection  322   b  contacts and temporarily deforms flange  334   a  of one-way valve  334  breaking the seal formed with seating  326  and allowing air to exit inflatable bladder  330 . In the “off” position, inflatable bladder does not inflate. In the example of  FIGS. 3A and 3B , notches  324   g  engage protrusion  312   f  when the cap  306  is rotated to the “auto” position and to the “off” position. 
       FIG. 4  provides a top view of deflation mechanism  302  and apron  304 , with lever  308  in the “down” position. Notches  324   g  and protrusion  312   f  let the user know the “auto” and “off” positions by feeling the cap  306  snap into position. Further, indicators  310  are printed or otherwise provided on apron  304  and a mark  340  on the upper surface  317  of cap  306  alert the wearer as to the amount of rotation of cap  306  with respect to base  312  and as to the “auto” and “off” positions of deflation mechanism  302 . 
     A lower profile deflation mechanism of the present invention need not be limited to an “auto”/“off” deflation mechanism, such as deflation mechanism  302  described above. A variety of deflation mechanisms may have a reduced profile by incorporating a lever, such as lever  308  discussed above and/or an apron, such as that previously described.  FIGS. 5A ,  5 B and  5 C illustrate an alternative embodiment of the present invention.  FIGS. 5A ,  5 B and  5 C are somewhat similar to a deflation mechanism described in Published U.S. Patent Application No. 2005/0028404, incorporated herein by reference in its entirety. However, along with other differences, deflation mechanism  502  includes a lever  508  having “up” and “down” positions such as that described in previous embodiments. Further, an apron  504  is provided in  FIG. 5C  to reduce the profile of deflation mechanism  502 . Deflation mechanism  502  is an adjustable check valve, wherein the predetermined pressure at which the valve releases is adjustable. 
     In particular, deflation mechanism  502  includes a cap  506  and a base  512 . Cap  506  is similar to cap  306  described above in that it has an upper cap piece  522  substantially similar to upper cap piece  322  previously described and a lower cap piece  524  substantially similar to lower cap piece  324  previously described. One variation in lower cap piece  324  and lower cap piece  524  of the present embodiment is that extended edge  324   c  is replaced herein with posts  544  which are discussed in further detail below. 
     Additionally, cap  506  includes an indicator mark  552  molded into upper cap piece  522  for aligning cap  506  with indicators formed in an adjacent apron  504  as illustrated in  FIG. 5C . Also, as shown in  FIG. 5A , lever  508  may include a pattern formed thereon, for example holes  554  or alternatively projections or additional materials printed thereon, which help a user grip lever  508 . 
     In this embodiment, base  512  includes a seating  526  having an inlet  528  into which a one-way valve  534  is positioned. As with the previous embodiments, a flange  534   a  of one-way valve  534  forms a seal with seating  526 . When the pressure within an inflatable bladder (not shown) reaches a predetermined pressure, flange  534   a  will lift off of seating  526  and air will be released from the inflatable bladder. Base  512  includes a sidewall  512   c . Sidewall  512   c  includes two inclined tracks  542 . Inclined tracks  542  engage posts  544  extending from an interior surface of cap  506 . As cap  506  turns with respect to base  512 , inclined tracks  542  move cap  506  towards and away from seating  526 . A washer  548  contacts a crown  534   b  of one-way valve  534 . A cylindrical protrusion  550  extends from an interior surface of cap  506 . 
     To adjust the resistance of one-way valve  534 , cap  506  is rotated via hinged lever  508 . Posts  544  engage inclined tracks  542  and move cap  506  towards and away from seating  526 , depending upon which direction cap  506  is rotated. When rotated in a first direction via lever  508 , cap  506  moves towards seating  526 . Cylindrical protrusion  550  contacts and applies pressure to washer  548 , which in turn applies pressure to crown  534   b  of one-way valve  534 . As pressure is applied to crown  534   b  of one-way valve  534 , the pressure at which flange  534   a  lifts off of seating  526  is increased. Thus, inflatable bladder (not shown) will inflate to a higher pressure. Turning cap  506  in an opposite direction moves cap  506  in a direction away from seating  526  and lifts cylindrical protrusion  550  off washer  548 , releasing the pressure on crown  534   b  of one-way valve  534 . Thus, inflatable bladder will inflate to a lower pressure before flange  534   a  of one-way valve  534  lifts off of seating  526 . As cap  506  turns, washer  548  does not twist or turn as ribs (not shown) on sidewall  512   c  of the base  512  engage a notch (not shown) in washer  548 , ensuring that only a downward pressure is applied to one-way valve  534  to avoid one-way valve  534  twisting or turning and becoming unseated or damaged. 
     With respect to  FIG. 5C , apron  504  includes ramped sides  504   b  which may include indicators, such as indicators  110  of  FIGS. 1A and 1B . Indicators may include a scale of pressures to which inflatable bladder may be inflated to indicate to the wearer whether the pressure in inflatable bladder is increasing or decreasing as cap  506  is turned. 
     In another embodiment, various notches (not shown) in cap  506  may engage a protrusion (not shown) in base  512  or sidewall  512   c , or vice versa, such that the wearer may feel the protrusion snap into the various notches to suggest a change in release pressure of the one-way valve  534 . Such a feature would operate similar to protrusion  312   f  and notch  324   g  described above with respect to  FIGS. 3A and 3B . In this embodiment, however, there may be several notches to show a range of release pressures. 
       FIGS. 6A-6F  illustrate another embodiment of the present invention.  FIG. 6A  illustrates shoe  600  having an upper  603  and a sole  605 . Shoe  600  also includes an inflatable bladder (not shown) and a deflation mechanism  602 . Deflation mechanism  602  may be, for example, any of the deflation mechanisms described herein. Deflation mechanism  602  includes a cap  617 . In order to obtain a low profile for cap  617 , deflation mechanism  602  includes an apron  604 . Rather than having a lever incorporated into cap  617 , the embodiment of  FIGS. 6A-6F  incorporates a removable apron  604 , as illustrated in  FIGS. 6D-6F . 
     Apron  604  has a first end  604   a  which is coupled to a portion of upper  603  of shoe  600 . In the present example, first end  604   a  of apron is hingedly connected to upper  603 , for example at stitches  660 . Alternatively, first end  604   a  may be hingedly connected to a plate (not shown) or other substrate affixed to an exterior surface of upper  603 . Stitches  660  allow apron  604  to hinge away from cap  617 . Alternatively, apron  604  may be attached to upper  603  via another hinged connection. For example, stitches  660  may be replaced with any type of metal or plastic hinge that may be apparent to one skilled in the art. Alternatively, apron  604  may be formed from a plate (not shown) that is incorporated into a portion of upper  603  and the hinged connection is formed where a apron  604  is formed from a thinner or weakened area of the plate that is flexible. 
     As illustrated in  FIGS. 6E and 6F , once apron  604  is hingedly removed from around cap  617 , cap  617  is accessible to a wearer&#39;s fingers for adjusting the maximum pressure within the inflatable bladder. 
     A second end  604   b  of apron  604  includes a male fastener  662 . Male fastener  662  removably engages a female fastener  664  affixed to upper  603  of shoe  600 , or, for example, to a plate or other substrate affixed to an exterior surface of upper  603 , in one embodiment, the same surface to which first end  604   a  of apron  604  is fastened. As illustrated in  FIGS. 6D-6F , cap  617  may be accessed by lifting apron and disengaging male fastener  662  from female fastener  662 . In the examples shown in  FIGS. 6A-6F , male and female fasteners  662 / 664  are illustrated as a snap fastener. In alternative embodiments, male and female fastener may be any type of fastener that provides temporary connection. For example, male and female fasteners may be hook and pile material, zipper, button, clasp or switch or any other type of fastener. Male and female fasteners  662 / 664  keep apron  604  flush against upper  603  when cap  617  is not being adjusted so that apron  604  and cap  617  keep a low profile to avoid damage to cap  617  during athletic activity. 
     Apron  604  hinges at first end  604   a  to provide access to turn cap  617  by grasping cap  617  along a textured side  666  of cap  617 . Side  666  may be textured by including a high friction material, such as rubber or silicon, to an exterior side of cap  617 . Alternatively, cap  617  may incorporate a lever (such as lever  108  illustrated in previous examples) to assist in turning cap  617 . 
     As illustrated in  FIGS. 6E and 6F , an indicator  668  may be provided on either an exterior surface of upper  603  adjacent cap  617  or on any plate (not shown) or other substrate provided that may be affixed to upper  603  adjacent cap  617 . 
     While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.