Patent Publication Number: US-8122536-B2

Title: Bed with collapsible frame

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of Chinese Patent Application 200620086530.3 entitled “A Bed with Improved Support Structure and An Improved Collapsible Support Base,” filed on Jun. 28, 2006, which is hereby incorporated by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     This invention relates generally to foldable and/or collapsible furniture and, more particularly, to a bed having a collapsible frame or base. 
     Conventional collapsible beds may include an air mattress that is supported by a collapsible frame. At least one such frame includes a plurality of uprights, which are joined by pivot assemblies such that the support frame as a whole expands outwardly from a central area when a portion of the frame is pulled outwardly. With the frame expanded, the uprights support an air mattress positioned on the uprights. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one aspect, a frame is provided. The frame includes a plurality of connector assemblies and a cross-support unit coupled between the plurality of connector assemblies. The cross-support unit is movable between a folded configuration and an expanded configuration. The cross-support unit defines a substantially planar support structure in the expanded configuration. 
     In another aspect, a frame is provided. The frame includes a plurality of first connector assemblies and a plurality of second connector assemblies. A cross-support unit is coupled between the plurality of first connector assemblies and the plurality of second connector assemblies. The cross-support unit is movable between a folded configuration and an expanded configuration. The cross-support unit defines a substantially planar support structure in the expanded configuration. 
     In another aspect, a frame is provided. The frame includes a plurality of connector assemblies. A cross-support unit is coupled between the plurality of connector assemblies and is movable between a folded configuration and an expanded configuration. An extendible support member is coupled between a first connector assembly of the plurality of connector assemblies and a laterally aligned second connector assembly of the plurality of connector assemblies. The extendible support member is movable between a retracted configuration and an extended configuration. 
     In another aspect, a frame is provided. The frame includes a first connector assembly having a first portion and a second portion movably coupled to the first portion to facilitate moving the frame between a collapsed configuration and an expanded configuration. A second connector assembly is laterally aligned with the first connector assembly. A cross-support unit is coupled between the first connector assembly and the second connector assembly. 
     In another aspect, a frame is provided. The frame includes a plurality of first connector assemblies and a plurality of second connector assemblies. Each second connector assembly of the plurality of second connector assemblies is laterally aligned with a corresponding first connector assembly of the plurality of first connector assemblies. Each of a plurality of first upright members is pivotally coupled to a corresponding first connector assembly and each of a plurality of second upright members is pivotally coupled to a corresponding second connector assembly. 
     In another aspect, a frame is provided. The frame includes a plurality of first connector assemblies positioned along a longitudinal axis of the frame and a plurality of second connector assemblies. A first cross-support unit is coupled between the plurality of first connector assemblies and the plurality of second connector assemblies. The first cross-support unit is movable between a folded configuration and an expanded configuration such that at least one first connector assembly of the plurality of first connector assemblies moves along the longitudinal axis. The first cross-support unit defines a substantially planar support structure in the expanded configuration. 
     In another aspect, a bed is provided. The bed includes a frame including a plurality of connector assemblies and a cross-support unit coupled between the plurality of connector assemblies. The cross-support unit is movable between a folded configuration and an expanded configuration. The cross-support unit defines a substantially planar support structure in the expanded configuration. A mattress is supported by the frame. 
     In another aspect, a bed is provided. The bed includes a collapsible frame including a plurality of first connector assemblies and a plurality of second connector assemblies. A cross-support unit is coupled between the plurality of first connector assemblies and the plurality of second connector assemblies. The cross-support unit is movable between a folded configuration and an expanded configuration. The cross-support unit defines a substantially planar support structure in the expanded configuration. A mattress is coupled to the collapsible frame. 
     In another aspect, a method for constructing a bed having a collapsible frame is provided. The method includes providing a frame including a plurality of connector assemblies and a cross-support unit coupled between the plurality of connector assemblies. The cross-support unit is moved between a folded configuration and an expanded configuration to define a substantially planar support structure in the expanded configuration. 
     In another aspect, a method is provided for constructing a bed having a collapsible frame. The method includes providing a frame including a plurality of first connector assemblies, a plurality of second connector assemblies, and a cross-support unit coupled between the plurality of first connector assemblies and the plurality of second connector assemblies such that the plurality of first connector assemblies move along a longitudinal axis of the frame as the cross-support unit moves from a folded configuration to an expanded configuration. The cross-support unit is moved between the folded configuration and the expanded configuration to define a substantially planar support structure in the expanded configuration. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an exemplary collapsible frame in an expanded configuration; 
         FIG. 2  is a perspective view of the collapsible frame shown in  FIG. 1  in a partially folded configuration; 
         FIG. 3  is a perspective view of the collapsible frame shown in  FIG. 1  in a folded configuration; 
         FIG. 4  is a perspective view of the collapsible frame shown in  FIG. 1  in a collapsed configuration; 
         FIG. 5  is an enlarged view of a portion of the collapsible frame shown in  FIG. 2 ; 
         FIG. 6  is an enlarged view of a portion of the locking device shown in  FIG. 5 ; 
         FIG. 7  is an enlarged view of a portion of the collapsible frame shown in  FIG. 3 ; 
         FIG. 8  is a perspective view of a bed with the collapsible frame in the expanded configuration and supporting a mattress; 
         FIG. 9  is an exploded perspective view of the bed shown in  FIG. 8 ; 
         FIG. 10  is a perspective view of the bed shown in  FIG. 8  with a portion of an outer liner removed to show an air mattress assembly; 
         FIG. 11  is a perspective view of a bottom surface of the air mattress assembly; 
         FIG. 12  is a perspective view of an alternative exemplary collapsible frame in an expanded configuration; 
         FIG. 13  is a perspective view of the collapsible frame shown in  FIG. 12  in a partially folded configuration; 
         FIG. 14  is a perspective view of the collapsible frame shown in  FIG. 12  in a folded configuration; 
         FIG. 15  is a perspective view of the collapsible frame shown in  FIG. 12  in a collapsed configuration; 
         FIG. 16  is an enlarged view of a portion of the collapsible frame shown in  FIG. 12 ; 
         FIG. 17  is an enlarged, exploded view of a portion of the locking device shown in  FIG. 16 ; 
         FIG. 18  is an enlarged view of a portion of the locking device shown in  FIG. 16 ; 
         FIG. 19  is an enlarged view of a portion of the collapsible frame shown in  FIG. 12 ; and 
         FIG. 20  is a perspective view of a bottom surface of an air mattress assembly suitable for use with the collapsible frame shown in  FIG. 12 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention provides a collapsible frame for a bed that forms a substantially planar support structure in an expanded configuration suitable for supporting a mattress, such as an air mattress. The bed is configured in a collapsed position for easy storage and/or transport. For example, in the collapsed configuration, the bed may be contained within a storage bag. When a sleeping area is desired, the frame is movable from the collapsed configuration to an intermediary folded configuration. The substantially planar support structure is then formed by moving the frame from the folded configuration to the extended configuration. A mattress is positioned on and support by the frame in the expanded configuration. In one embodiment, the mattress is removably coupled to the frame in the expanded configuration. 
     The present invention is described below in reference to its application in connection with and operation of a bed having a collapsible frame. However, it should be apparent to those skilled in the art and guided by the teachings herein provided that the invention is likewise applicable to any suitable foldable and/or collapsible furniture piece. 
     Referring to  FIGS. 1-20 , a bed  100  (shown in the  FIGS. 8-10 ) includes a collapsible frame  10  and a mattress  12 , such as an air mattress. In one embodiment, frame  10  includes a plurality of connector assemblies and a cross-support unit coupled between the connector assemblies. The cross-support unit is movable between a folded configuration and an expanded configuration to define a substantially planar support structure for supporting mattress  12 . As frame  10  is moved between the folded configuration and the expanded configuration, a plurality of first connector assemblies move along or parallel with a longitudinal axis of the bed. Frame  10  is also movable from the folded configuration to a collapsed configuration to facilitate storing and/or transporting the bed. 
     Referring further to  FIGS. 1-11 , collapsible frame  10  includes a plurality of connector assemblies coupled to a corresponding upright member. In one embodiment, collapsible frame  10  includes a plurality of first or middle connector assemblies  16  pivotally coupled to a corresponding first upright member  17 , a plurality of second lateral edge connector assemblies  18  pivotally coupled to a corresponding second upright member  19 , and a plurality of third or lateral edge connector assemblies  20  pivotally coupled to a corresponding third upright member  21 . In one embodiment, first connector assemblies  16  are aligned along a longitudinal axis  22  of collapsible frame  10  and movable along longitudinal axis  22  to facilitate moving collapsible frame  10  between an extended position, such as shown in  FIG. 1 , and a folded position, such as shown in  FIG. 3 . Further, as shown in  FIG. 1 , each first connector assembly  16  is laterally aligned with a corresponding second connector assembly  18  and a corresponding third connector assembly  20  along or parallel with a lateral axis  23  substantially perpendicular to longitudinal axis  22 . In one embodiment, each first connector assembly  16  includes a first portion  24  and a second portion  26  pivotally coupled to first upright member  17 , as shown in  FIG. 7 . In the extended configuration, first portion  24  and second portion  26  are coupled such that corresponding first upright member  17  is coterminous with first portion  24  and second portion  26  to provide a flush top upright member end portion providing an aesthetically pleasing connector assembly as well as preventing undesirable contact with the user. Second connector assemblies  18  define a first lateral edge of collapsible frame  10  and third connector assemblies  20  define an opposing second lateral edge of collapsible frame  10 . 
     A substantially planar support structure  30  is formed between first connector assemblies  16  and second connector assemblies  18  and between first connector assemblies  16  and third connector assemblies  20 . Substantially planar support structure  30  is configured to support mattress  12 . More specifically, substantially planar support structure  30  includes at least one foldable cross-support unit  32 . In one embodiment, a plurality of cross-support units  32  are movable between an extended configuration, as shown in  FIG. 1 , to define substantially planar support structure  30 , and a folded configuration, as shown in  FIG. 3 . Further, cross-support units  32  are pivotally movable with respect to upright members  17  between the folded configuration and a collapsed configuration, as shown in  FIG. 4 , to facilitate storing and/or transporting frame  10 . Each cross-support unit  32  is coupled between a plurality of connector assemblies. For example, referring further to  FIG. 1 , a first cross-support unit  32  is coupled between a plurality of first connector assemblies  16  and a plurality of second connector assemblies  18 . Similarly, a second cross-support unit  32  is coupled between a plurality of first connector assemblies  16  and a plurality of third connector assemblies  20 . 
     Cross-support unit  32  includes a first member  34  and a second member  36  coupled together. Each first member  34  and second member  36  has a first end  37 , a second end  38  and an intermediate point  40  therebetween. First member  34  is pivotally coupled to second member  36  at a respective intermediate point  40 . First member  34  is coupled to a corresponding first connector assembly  16  at first end  37  and to a corresponding second connector assembly  18  at second end  38 . Similarly, second member  36  is coupled to a corresponding first connector assembly  16  at first end  37  and to a corresponding second connector assembly  18  at second end  38 . Each first member  34  and each second member  36  are coupled to first portion  24  of a corresponding first connector assembly  16  such that cross-support unit  32  is pivotally movable with respect to first upright members  17  about longitudinal axis  22 . More specifically, with cross-support unit  32  in the folded configuration, each first member  34  and each second member  36  is pivotally movable with respect to a corresponding first upright member  17  about longitudinal axis  22  to move frame  10  towards the collapsed configuration. 
     Similarly, the second cross-support unit  32  includes first member  34  and second member  36  coupled together at intermediate point  40 . First member  34  is coupled to a corresponding first connector assembly  16  at first end  37  and to a corresponding third connector assembly  20  at second end  38 . Similarly, second member  36  is coupled to a corresponding first connector assembly  16  at first end  37  and to a corresponding third connector assembly  20  at second end  38 . Each first member  34  and each second member  36  are coupled to second portion  26  of a corresponding first connector assembly  16  such that cross-support unit  32  is pivotally movable with respect to first upright members  17  about longitudinal axis  22 . More specifically, with cross-support unit  32  in the folded configuration, each first member  34  and each second member  36  is pivotally movable with respect to a corresponding first upright member  17 . 
     In one embodiment, at least one extendible support member  41  is positioned between adjacent laterally aligned connector assemblies. For example, as shown in  FIG. 1 , at least one extendible support member  41  is coupled between a first connector assembly  16  and a corresponding second connector assembly  18 . Similarly, at least one extendible support member  41  may be coupled between a first connector assembly  16  and a corresponding third connector assembly  20 . 
     As shown in  FIGS. 5 and 6 , extendible support member  41  includes members that are movable with respect to each other to extend and retract extendible support member  41 , such as a telescopic assembly  42 . In one embodiment, telescopic assembly  42  includes a first or outer member  44  and a sleeve  46  coupled to an end portion of outer member  44 . Sleeve  46  defines a sliding slot  48  communicating with an aperture  49 . A second or inner member  50  is slidably coupled within outer member  44  and a locking device  52  fixedly couples outer member  44  and inner member  50 . Locking device  52  includes a spring bracket  54  positioned within inner member  50 . In one embodiment, spring bracket  54  is coupled to an inner surface of inner member  50  using a suitable fastener, such as a screw or rivet, and/or a weld to retain spring bracket  54  properly positioned within inner member  50 . In alternative embodiments, other suitable mechanisms may be used to retain spring bracket  54  properly positioned within inner member  50 . 
     Referring further to  FIG. 6 , spring bracket  54  includes a first end  55 , a second end  56  generally opposing first end  55  and a bend portion  57  between first end  55  and second end  56 . Spring bracket  54  includes a first locking projection  58  at first end  55  that is configured to extend through a first opening  59  defined within inner member  50  under application of a suitable force and a second locking projection  60  between first end  55  and bend portion  57  that is configured to extend through a second opening  62  defined within inner member  50  under application of a suitable force. Bend portion  57  is configured to apply a force that urges first end  55  to diverge from second end  56 . This divergent force is sufficient to urge first locking projection  58  and second locking projection  60  into respective openings  59  and  62  with inner member  50  aligned with outer member  44 . First locking projection  58  is movably positioned within sliding slot  48  defined within sleeve  46  such that first locking projection  58  extends into aperture  49  to lock outer member  44  with respect to inner member  50 . To unlock locking device  52 , a suitable force is applied to first locking projection  58  such that first end  55  of spring bracket  54  is moved inwardly with respect to inner member  50  toward second end  56 . As first end  55  moves inwardly, first locking projection  58  is released from aperture  49  and from within sliding slot  48  to allow outer member  44  to move with respect to inner member  50 . 
     Referring again to  FIG. 4 , in one embodiment, each first connector assembly  16  is pivotally coupled to a corresponding first upright member  17 . In a particular embodiment, first upright member  17  forms a slide groove  70  or other suitable void. A cooperating pivot extends at least partially into slide groove  70  to facilitate properly positioning first connector assembly  16  with respect to first upright member  17 . 
     As shown in  FIG. 7 , first portion  24  and second portion  26  of first connector assembly  16  are frictionally fitted together to facilitate coupling first portion  24  to second portion  26 . In one embodiment, first portion  24  includes a projection  80  and second portion  26  defines a cooperating void (not shown in  FIG. 6 ) within which projection  80  is positioned to coupled first portion  24  to second portion  26 . 
     In a further embodiment, frame  10  includes additional support members, such as a first frame member  90  and/or a second frame member  92 . As shown in  FIG. 1 , first frame member  90  extends between and is pivotally coupled to first portion  24  of first connector assembly  16  and a laterally aligned second upright member  19 . Second frame member  92  extends between and is pivotally coupled to second portion  26  of first connector assembly  16  and a laterally aligned third upright member  21 . First frame members  90  and second frame members  92  facilitate moving the associated upright members as cross-support unit  32  is moved between the folded configuration and the expanded configuration to facilitate easy construction or collapsing of frame  10 , as desired. 
     More specifically, as cross-support unit  32  is moved from the folded configuration to the expanded configuration, extendible support member  41  coupled between first portion  24  of first connector assembly  16  and a corresponding second connector assembly  18  moves from the extended configuration to the retracted configuration and second upright members  19 , coupled via first frame member  90  to first portion  24 , pivot outwardly with respect to cross-support unit  32 . With cross-support unit  32  in the expanded configuration, second upright members  19  are substantially perpendicular to cross-support unit  32 . As cross-support unit  32  is moved from the expanded configuration to the folded configuration, extendible support member  41  moves from the retracted configuration to the extended configuration and second upright members  19  pivot inwardly towards cross-support unit  32 . In one embodiment, movement of extendible support member  41  facilitates urging second upright members  19  to pivot. With cross-support unit  32  in the folded configuration, second upright members  19  are substantially parallel to cross-support unit  32 . Further, with cross-support unit  32  in the folded configuration, cross-support unit  32  is pivotally movable with respect to first upright members  17  to facilitate moving frame  10  towards the collapsed configuration. More specifically, cross-support unit  32  pivots with respect to first upright member  17  through first portion  24  of first connector assembly  16  pivotally coupled to first upright member  17 . 
     Similarly, as a laterally opposing second cross-support unit  32  is moved from the folded configuration to the expanded configuration, a second extendible support member  41  coupled between second portion  26  of first connector assembly  16  and a corresponding third connector assembly  20  moves from the extended configuration to the retracted configuration and third upright members  21 , coupled via second frame member  92  to second portion  26 , pivot outwardly with respect to second cross-support unit  32 . In one embodiment, movement of extendible support member  41  facilitates urging third upright members  21  to pivot. With second cross-support unit  32  in the expanded configuration, third upright members  21  are substantially perpendicular to second cross-support unit  32 . As second cross-support unit  32  is moved from the expanded configuration to the folded configuration, second extendible support member  41  moves from the retracted configuration to the extended configuration and third upright members  21  pivot inwardly towards second cross-support unit  32 . With second cross-support unit  32  in the folded configuration, third upright members  21  are substantially parallel to second cross-support unit  32 . Further, with second cross-support unit  32  in the folded configuration, second cross-support unit  32  is pivotally movable with respect to first upright members  17  to facilitate moving frame  10  towards the collapsed configuration. More specifically, second cross-support unit  32  pivots with respect to first upright member  17  through second portion  26  of first connector assembly  16  pivotally coupled to first upright member  17 . 
     Referring to  FIGS. 8-11 , bed  100  includes collapsible frame  10  and mattress  12 , including in one embodiment an air mattress assembly  102 , removably coupled to frame  10 . In a particular embodiment, air mattress assembly  102  includes a covering  104  and a fabric skirt  106 . A plurality of fasteners  110 , such as a fastener having a L-shape, are coupled to a bottom surface  112  (shown in  FIG. 11 ) of covering  104 . Covering  104  defines a compartment  114  configured to receive an air mattress  116 . Compartment  114  is opened or closed, as desired, using a suitable fastener component, such as a zipper. In one embodiment, fasteners  110  are generally aligned in rows. Each fastener  110  includes a projection  120  that is removably inserted into a recess formed on corresponding first connector assembly  16 , second connector assembly  18  or third connector assembly  20 . 
     In an alternative embodiment, as shown in  FIGS. 12-20 , an alternative exemplary collapsible frame  130  is provided that includes components that are similar to like components of collapsible frame  10 , unless otherwise described below. Thus, identical element reference numbers are used to describe components of collapsible frame  130  that are similar to like components of collapsible frame  10  described above. Collapsible frame  130  includes at least one extendible support member  141  having members that are movable with respect to each other to extend and retract extendible support member  141 , such as a telescopic assembly  142 . In one embodiment, telescopic assembly  142  includes a first or outer member  144  that defines a first opening  146  and a flexible member  148 . A second or inner member  150  is slidably coupled within outer member  144  and defines a second opening  152  that can be aligned with first opening  146 . A spring bracket  160  is positioned within inner member  150 . Spring bracket  160  includes a locking projection  162  that is positionable within second opening  152  and first opening  146 . Flexible member  148  is integrated with or coupled to outer member  144  and forms a projection, such as a boss  180  shown in  FIG. 18 , which is configured to be positioned within first opening  146 . In one embodiment, boss  180  has a size and shape configured to extend at least partially within first opening  146 . To unlock outer member  144  from inner member  150 , a suitable force is applied to flexible member  148  such that boss  180  extends into first opening  146  to urge spring bracket  160  inwardly with respect to inner member  150 . As spring bracket  160  moves inwardly, locking projection  162  is pushed inwardly through first opening  146  and is released from within first opening  146  to allow outer member  144  to move with respect to inner member  150 . 
     Referring to  FIGS. 19 and 20 , in a further alternative embodiment, bed  100  includes a buckle arrangement  182  including a buckle  184  configured to releasably engage a socket  186 . In one embodiment, buckle  184  is configured to snap-fit within socket  186 . Air mattress assembly  102  includes a plurality of buckles  184  in addition to or in lieu of fasteners  110 . In a particular embodiment, buckles  184  are coupled to bottom surface  112  of covering  104 . Each buckle  184  facilitates coupling one of the four corners of covering  104  to frame  10 . More specifically, each buckle  184  is releasably engaged with a corresponding socket  186  formed within or coupled to a respective connector assembly, such as second connector assembly  18  or third connector assembly  20 , as shown in  FIG. 19 . A suitable force is applied to buckle  184  such that tabs  188  move from an initial position laterally inwardly as buckle  184  slidably engages edge portions  190  of socket  186  at least partially defining a corresponding void  192 . As tab  188  is slidably positioned within corresponding void  192 , tab  188  moves laterally outwardly towards the initial position. In the initial position, tab  188  facilitates retaining buckle  184  engaged with socket  186 . To release buckle  184  from within socket  186 , a suitable force is applied to tabs  188  to urge tabs laterally inwardly such that buckle  184  can be slidably removed from within socket  186 . 
     In one embodiment, a method for constructing or making a bed having a collapsible frame is provided. The frame includes a plurality of connector assemblies and a cross-support unit coupled between the plurality of connector assemblies. In a particular embodiment, at least one connector assembly of the plurality of connector assemblies moves parallel to a longitudinal axis of the frame as the frame moves from a folded configuration to an expanded configuration. The cross-support unit is moved between the folded configuration and the expanded configuration to define a substantially planar support structure in the expanded configuration suitable for supporting a mattress. 
     In one embodiment, the frame includes a plurality of first connector assemblies, a plurality of second connector assemblies, and a cross-support unit coupled between the plurality of first connector assemblies and the plurality of second connector assemblies such that the plurality of first connector assemblies move along a longitudinal axis of the frame as the frame moves from a folded configuration to an expanded configuration. The cross-support unit is moved between the folded configuration and the expanded configuration to define the substantially planar support structure in the expanded configuration. As the cross-support unit is moved from the folded configuration to the expanded configuration, a distance between adjacent first connector assemblies is increased. In a particular embodiment, each first connector assembly includes a first portion and a cooperating second portion. As the cross-support unit is moved, the first portion is coupled to the second portion to facilitate retaining the collapsible frame in the expanded configuration. In a further embodiment, a projection formed on or coupled to the first portion is positioned within a slot defined within the second portion. With the frame in the expanded configuration, a mattress is positioned on the substantially planar support structure. 
     In a particular embodiment, an extendible support member is coupled between one first connector assembly and a corresponding laterally aligned second connector assembly or laterally aligned third connector assembly. As the cross-support unit is moved, the extendible support member also moves from an extended configuration and a retracted configuration. The extendible support member can be locked in the desired configuration. 
     Further, the cross-support unit is pivotally movable with respect to a plurality of first upright members each coupled to a corresponding first connector assembly to facilitate moving the frame between the folded configuration and a collapsed configuration for storing and/or transporting the frame. A plurality of second upright members are pivotally coupled to a corresponding first member or corresponding second member of the cross-support unit. Each second upright member is pivotally moved with respect to the corresponding first member or second member to facilitate moving the frame to the collapsed configuration. 
     The above-described bed and collapsible frame facilitate providing a sleeping area quickly and efficiently. More specifically, the collapsible frame is movable between a collapsed configuration, facilitating storage and/or transportation of the bed, and an expanded configuration defining a substantially planar support structure configured to support a mattress. 
     Exemplary embodiments of a collapsible frame and method of constructing or making a bed are described above in detail. The apparatus and method are not limited to the specific embodiments described herein, but rather, components of the apparatus and/or steps of the method may be utilized independently and separately from other components and/or steps described herein. Further, the described apparatus components and/or method steps can also be defined in, or used in combination with, other apparatus and/or methods, and are not limited to practice with only the apparatus and method as described herein. 
     While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.