Patent Publication Number: US-8973939-B2

Title: Adjustable seating frame and footrest assemblies

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to and the benefit of U.S. Provisional patent application Ser. No. 61/599,555, entitled “ADJUSTABLE SEATING FRAME AND FOOTREST ASSEMBLIES” and filed Feb. 16, 2012, the entire disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND 
     Conventional wheelchairs are provided with footrest assemblies including footrest hangers mounted to a seating frame of the wheelchair, and footrest plates secured to the footrest hangers for supporting the wheelchair occupant&#39;s feet in a raised, off-the-floor position. 
     SUMMARY 
     The present application discloses exemplary embodiments of adjustable seating frames and footrest assemblies for use with a variety of apparatuses, including, for example, a wheelchair. In one exemplary embodiment, an adjustable seating frame assembly is configured to position a footrest assembly (e.g., a footrest hanger and footrest plate) in a selected angled forward extending position. In another exemplary embodiment, an adjustable footrest assembly is configured to position a footrest plate in at least one of an angled planar position with respect to a footrest hanger, and a planar position within a plane defined by the footrest plate. 
     Accordingly, in an exemplary embodiment, an adjustable seating frame assembly for a wheelchair includes a side frame member, a first joint member affixed to the side frame member, a footrest hanger, and a second joint member affixed to the footrest hanger. The first and second joint members each include a pivot aperture and at least one lock aperture. A pivot fastener is secured through the pivot apertures of the first and second joint members to pivotally attach the second joint member to the first joint member. A lock fastener is secured through selected ones of the lock apertures of the first and second joint members to secure the second joint member in a selected angular position with respect to the first joint member. The second joint member is securable to the first joint member in a plurality of angular positions with respect to the first joint member. 
     In another exemplary embodiment, a method is contemplated for adjusting an angle of a footrest hanger on a wheelchair having a side frame member secured to a first joint member and a footrest hanger secured to a second joint member. The footrest hanger and the second joint member are pivoted about a pivot fastener secured through aligned pivot apertures in the first and second joint members to a selected angular position of the footrest hanger. A lock fastener is installed through aligned lock apertures in the first and second joint members to secure the footrest hanger in the selected angular position. 
     In still another exemplary embodiment, an adjustable footrest assembly for a wheelchair includes a footrest hanger having a vertically extending section, a footrest plate having a substantially planar foot supporting surface, a mounting bracket secured to the vertically extending section of the footrest hanger, and a ball joint including a ball portion received in a concave spherical recess in the mounting bracket and a stem portion secured to the footrest plate. A clamping member is disposed between the footrest plate and the mounting bracket, and assembled with the mounting bracket to clamp the ball portion of the ball joint between the clamping member and the mounting bracket. 
     In yet another exemplary embodiment, a method is contemplated for positioning a footrest plate on a wheelchair including a side frame member secured to a first joint member, a footrest hanger secured to a second joint member, a mounting bracket secured to the footrest hanger, and a footrest plate secured to the mounting bracket. In the exemplary method, the footrest hanger and the second joint member are pivoted with respect to the first joint member, to a selected angular position of the footrest hanger. The footrest hanger and the second joint member are secured in the selected angular position. The footrest plate is positioned in a selected planar position, and the footrest plate is secured in the selected planar position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features and advantages will become apparent to those of ordinary skill in the art to which the invention pertains from a reading of the following description together with the accompanying drawings, in which: 
         FIG. 1A  is partial top schematic view of an adjustable footrest assembly shown in a first angular position, according to an exemplary embodiment; 
         FIG. 1B  is a partial top schematic view of the adjustable footrest assembly of  FIG. 1A , shown in a second angular position; 
         FIG. 1C  is a partial top schematic view of the adjustable footrest assembly of  FIG. 1A , shown in a third angular position; 
         FIG. 2  illustrates an upper perspective view of an adjustable footrest assembly, according to an exemplary embodiment; 
         FIG. 3  illustrates a partial exploded upper perspective view of the adjustable footrest assembly of  FIG. 2 ; 
         FIG. 4A  illustrates a top view of the adjustable footrest assembly of  FIG. 2 , shown with the footrest hanger in a first angular position; 
         FIG. 4B  illustrates a top view of the adjustable footrest assembly of  FIG. 2 , shown with the footrest hanger in a second angular position; 
         FIG. 4C  illustrates a top view of the adjustable footrest assembly of  FIG. 2 , shown with the footrest hanger in a third angular position; 
         FIG. 5  illustrates a side cross-sectional view of the footrest assembly of  FIG. 2 ; 
         FIG. 6  illustrates another side cross sectional view of the footrest assembly of  FIG. 2 ; and 
         FIG. 7  illustrates a perspective view of a wheelchair assembly including the footrest assembly of  FIG. 2 . 
     
    
    
     DESCRIPTION 
     This Description merely describes exemplary embodiments and is not intended to limit the scope of the claims in any way. Indeed, the invention as claimed is broader than and unlimited by the exemplary embodiments, and the terms used in the claims have their full ordinary meaning. 
     As described herein, when one or more components are described as being connected, joined, affixed, coupled, attached, or otherwise interconnected, such interconnection may be direct as between the components or may be indirect, such as through the use of one or more intermediary components. Also as described herein, reference to a “member,” “component,” or “portion” shall not be limited to a single structural member, component, or element but can include an assembly of components, members or elements. 
     Wheelchairs are generally provided with leg support frame and footrest assemblies that are oriented to support standard or neutral skeletal alignment of the lower extremities (e.g., pelvis, legs, ankles, and feet). When a wheelchair user possesses moderate to severe skeletal deformities of these lower extremities (for example, due to birth defects, accidents, ailments, or historic long term wheelchair use), the resulting deviation from this neutral alignment often requires specialized or adapted components to enable the leg support frame and footrest assemblies to accommodate the user. These specialized adaptations (e.g., a foot retaining box bolted to the footrest plate) add cost, size, and complexity to the wheelchair, and draw unwanted attention to the deformities of the user. 
     According to one aspect of the present application, an adjustable seating frame and footrest assembly for a wheelchair is configured to accommodate a range of lower extremity positioning requirements of a wheelchair user. In one such embodiment, a horizontally pivoting joint (i.e., pivoting about a vertical axis) between the side frame member and the footrest hanger allows for adjustable angular positioning of the entire footrest hanger, for example, to accommodate lower skeletal deformities of the user, such as abduction, adduction, pelvic rotation, leg length deforminity, and/or windswept legs. 
     While many different configurations may be utilized to provide adjustable angular positioning of a footrest hanger (or some other seating frame component) with respect to a wheelchair side frame member, in an exemplary embodiment, a first joint member is secured to the side frame member and a second joint member is secured to the footrest hanger, with the second joint member being configured to be secured to the first joint member in a plurality of angular positions. In an exemplary embodiment, first and second pivotally connected joint members are each provided with one or more lock apertures positioned such that in a selected angular position of the second joint member, at least one of the one or more lock apertures of the first joint member aligns with at least one of the one or more lock apertures of the second joint member, to receive at least one lock fastener through the aligned lock apertures. In one embodiment, pivoting movement of the second joint member aligns a lock aperture in the first joint member with one of a plurality of lock apertures in the second joint member to provide for a plurality of angular positions of the second joint member. In another embodiment, pivoting movement of the second joint member aligns a lock aperture in the second joint member with one of a plurality of lock apertures in the first joint member to provide for a plurality of angular positions of the second joint member. In still another embodiment, each of the first and second joint members includes a plurality of lock apertures, with at least one of the plurality of first joint member lock apertures aligning with at least one of the plurality of second joint member lock apertures in any of the available angular positions of the second joint member. 
       FIGS. 1A-1C  schematically illustrate partial top schematic views of an exemplary adjustable seating frame assembly  10  (e.g., for a wheelchair) including a vertically extending footrest hanger  40  assembled with a horizontally extending side frame member  20 . A first joint member  30  is secured to the side frame member  20  (e.g., integrally or as an assembly), and a second joint member  50  is secured to the footrest hanger  40  (e.g., integrally or as an assembly). A wheelchair may, but need not, include an identical or mirror image second footrest assembly (not shown) on an opposite side of the wheelchair. 
     The first and second joint members  30 ,  50  each include pivot apertures  32 ,  52  that align to receive a pivot fastener  33  (e.g., a bolt or pin) about which the second joint member is permitted to pivot to adjust an angular position of the second joint member  50  with respect to the first joint member  30 , for example to adjust the orientation of a footrest  70 , mounted to the footrest hanger  40 , with respect to the side frame member  20 . In a first angular position of the second joint member ( FIG. 1A ), a first lock aperture  34  of the first joint member  30  aligns with a first lock aperture  54  of the second joint member  50  to receive a lock fastener  63 , which secures the second joint member  50  in the first angular position. In a second angular position of the second joint member  50  ( FIG. 1B ), a second lock aperture  35  of the first joint member  30  aligns with a second lock aperture  55  of the second joint member  50  to receive the lock fastener  63  (or any other suitable lock fastener), which secures the second joint member  50  in the second angular position. In a third angular position of the second joint member  50  ( FIG. 1C ), a third lock aperture  36  of the first joint member  30  aligns with the second lock aperture  55  of the second joint member  50  to receive the lock fastener  63  (or any other suitable lock fastener), which secures the second joint member  50  in the third angular position. 
     As shown, to accommodate multiple lock apertures on a relatively narrow joint member, the first joint member  30  may include at least one lock aperture  34  proximal to a terminal end  37  of the first joint member  30 , and at least one lock aperture  35 ,  36  distal to the terminal end  37  of the first joint member  30  and opposite the pivot aperture  32 . Similarly, the second joint member  50  may include at least one lock aperture  55  proximal to a terminal end  57  of the second joint member  50 , and at least one lock aperture  54  distal to the terminal end  57  of the second joint member  50  and opposite the pivot aperture  52 . 
     To adjust the angular position of the second joint member  50  with respect to the first joint member  30 , the lock fastener  63  is removed from the aligned lock apertures ( 34 ,  54 ;  35 ,  55 ; or  36 ,  55 ), and the footrest hanger  40  and second joint member  50  are pivoted about the pivot fastener  33  to a desired angular position coinciding with alignment of lock apertures of the first and second joint members  30 ,  50 . The lock fastener is installed through the newly aligned lock apertures ( 34 ,  54 ;  35 ,  55 ; or  36 ,  55 ) to secure the footrest hanger  40  and second joint member  50  in the selected angular position. 
     As described herein, the lock apertures may be provided as holes extending through the joints, as shown in  FIGS. 1A-1C . Alternatively, other features, such as notches, blind bores, counterbores, slots, or portions of slots may be utilized as lock apertures receiving at least a portion of a lock fastener. As one example (not shown), a slot having enlarged holes or cutouts corresponding to desired angular positions and sized to interlock with an enlarged lock fastener head may allow for adjustment of the angular position of the second joint member without complete removal of the lock fastener. 
     The adjustable seating frame and footrest assembly arrangements described above may be used with a variety of different wheel chair side frame members and footrest hangers. For example, the side frame member may include a square, rectangular, circular, or other cross-sectioned tubular member attached to a first joint member. The footrest hanger may be permanently or releasably attached to the second joint member. In one embodiment, a footrest hanger of a swing-away configuration is mounted to the second joint member for pivotal movement about a vertical axis between a position in front of the chair and a position beside the chair. Examples of swing-away footrest hanger configurations are described in U.S. Pat. Nos. 3,854,774 and 4,790,553, the entire disclosures of which are incorporated herein by reference. In another embodiment, a footrest hanger having a spring-loaded releasing mechanism may be releasably attached to a second joint member for easy detachment of the footrest hanger and footrest (e.g., to facilitate stowing or transportation of the wheelchair. An example of a spring-loaded releasing mechanism for a footrest hanger is described in U.S. Pat. No. 6,155,586, the entire disclosure of which is incorporated herein by reference. 
       FIGS. 2-6  illustrate various views of an exemplary adjustable seating frame and footrest assembly  100  including a vertically extending releasable footrest hanger  140  assembled with, and angularly adjustable with respect to, a horizontally extending tubular side frame member  120 . A first joint member  130  is received in an open end  121  of the side frame member, and is secured to the side frame member  120  by a bolt assembled through aligned holes in the first joint member  130  and side frame member  120 . A second joint member  150  is pivotally attached to the first joint member  130  and is configured to releasably attach to the footrest hanger  140 . A wheelchair may, but need not, include an identical or mirror image second footrest assembly on an opposite side of the wheelchair.  FIG. 7  illustrates an exemplary wheelchair  200  utilizing the exemplary adjustable seating frame and footrest assemblies  100  of  FIGS. 2-6 . 
     While any suitable detachable engagement between the second joint member and the footrest hanger may be utilized, in the illustrated embodiment, the second joint member  150  may be configured to engage the footrest hanger  140  at three separate locations, to provide additional support and rigidity for the footrest hanger. The exemplary second joint member  150  includes a horizontal tubular section  151  that retains a latch member  161  biased outward of the horizontal section by a spring  162  for interlocking engagement with a corresponding locking insert  148  of a footrest hanger  140  (see  FIG. 6 ). The second joint member  150  further includes a vertical tubular section  153  secured to the horizontal tubular section  151  by a gusset  164 , for receiving a downward extending fitting  143  of the footrest hanger  140 . As shown in  FIG. 6 , the second joint member may also include a support block  165  fastened to the vertical tubular section  153  (e.g., by a fastener  171 ) for supporting a horizontal brace  147  that extends from the vertical portion  142  of the footrest hanger  140  and abuts the vertical tubular section  153 . While the brace may be secured directly to the vertical portion, in the illustrated embodiment, the horizontal brace  147  is provided on a tee member  145  assembled with the vertical portion  142 . 
     Referring to  FIG. 6 , to lock the footrest hanger  140  with the second joint member  150 , the downward extending fitting  143  is inserted into the vertical tubular section  153  of the second joint member  150  and is pushed downward to compress a guide  166  within the vertical tubular section against a spring  168 . An angled surface  149  of the locking insert  148  engages a corresponding angled surface  157  of the latch member  152  to force the latch member against the spring  162  and into the horizontal tubular section  151 . When the insert angled surface  149  is pushed past the latch member angled surface  157 , the latch member  152  snaps outward (under force of spring  162 ) to interlock with the insert  148 . In this locked position, notches  144  in the fitting  143  receive a cross bolt  167  extending through the vertical tubular section  153 , to impede rotation of the footrest hanger  140  about the fitting  143 . A contoured bumper  146  at the end of the horizontal brace  147  abuts the vertical tubular section  153 , and the support block  165  engages an underside of the brace  147  to further reinforce the attachment. 
     To release the footrest hanger  140  from the second joint member  150 , a release lever  158 , pivotally connected to the gusset  164  and attached to the latch member  152  by a fastener  159  extending through a slot  156  in the horizontal tubular section, is pivoted to retract the latch member  152  out of interlocking engagement with the insert  148 . The spring loaded guide  166  then pushes the footrest hanger  140  upward, to allow rotation of the footrest hanger about the fitting  143  and to facilitate separation of the footrest hanger  140  from the second joint member  150 . 
     The exemplary first and second joint members  130 ,  150 , include overlapping semi-cylindrical end portions shaped to allow for pivoting movement of the second joint member with respect to the first joint member. Similar to the schematically illustrated assembly  10  of  FIGS. 1A-1C , the first and second joint members  130 ,  150  each include pivot apertures  132 ,  152  that align to receive a pivot fastener  133  (e.g., a bolt or pin) about which the second joint member  150  is permitted to pivot to adjust an angular position of the second joint member with respect to the first joint member  130  to adjust the orientation of a footrest  170 , mounted to the footrest hanger  140 , with respect to the side frame member  120 . In a first (neutral) angular position of the second joint member ( FIG. 4 ), a first lock aperture  134  of the first joint member  130  aligns with a first lock aperture  154  of the second joint member  150  to receive a lock fastener  163 , which secures the second joint member  150  in the first angular position. In a second (outward) angular position of the second joint member, a second lock aperture  135  of the first joint member  130  aligns with a second lock aperture  155  of the second joint member  150  to receive the lock fastener  163 , which secures the second joint member  150  in the outward angular position. In a third (inward) angular position of the second joint member  150 , a third lock aperture (not shown) of the first joint member  130  aligns with the second lock aperture  155  of the second joint member  150  to receive the lock fastener  163 , which secures the second joint member  150  in the third angular position. While the joint members bay be configured to accommodate any suitable or desirable angular position of the of the footrest hanger, in an exemplary embodiment, the lock apertures of the first and second joint members are positioned to accommodate a straight/neutral angular position, an angled left position (e.g., about 10°-30° from neutral, or about 22.5° from neutral), and an angled right position (e.g., about 10°-30° from neutral, or about 22.5° from neutral). 
     While the pivot fastener  133  and lock fastener  163  may include any suitable fasteners, in an exemplary embodiment, either or both of the fasteners  133 ,  163  are threaded fasteners configured to be tightened with threaded portions of the corresponding pivot apertures  132 ,  152  and/or lock apertures  134 ,  154 ;  135 ,  155 ;  136 ,  155  to provide a sturdy, robust attachment between the side frame member  120  and the footrest hanger  140  and footrest plate  170 , components that may be routinely subjected to substantial forces and impacts during use of the wheelchair. 
     To adjust the angular position of the second joint member  150  with respect to the first joint member  130 , the lock fastener  163  is removed from the aligned lock apertures, the pivot fastener  163  is loosened, and the footrest hanger  140  and second joint member  150  are pivoted about the pivot fastener  133  to a desired angular position coinciding with alignment of lock apertures of the first and second joint members  130 ,  150 . The lock fastener  163  is installed through the newly aligned lock apertures to secure the footrest hanger  140  and second joint member  150  in the selected angular position. 
     According to another aspect of the present application, a footrest plate may be adjustably secured to a footrest hanger, for example, to accommodate a variety of foot positions, including non-standard foot positions resulting from skeletal deformities of the legs, ankles, and feet. While the footrest plate may be hingedly attached to the footrest hanger for adjustment of a forward/rearward, proximal/distal, or swivel left/right angle of the footrest plate, in an exemplary embodiment, a footrest assembly is provided with a ball and socket joint arrangement configured to provide for secure positioning of the footrest plate in any combination of forward (toe down), rearward (toe up), lateral up, proximal up, and swivel positions, for example, to accommodate planar flexion, dorsal flexion, inversion, and eversion ankle and foot positioning requirements. 
     In the exemplary embodiment of  FIGS. 2-6 , a footrest plate mounting assembly  180  includes a footrest plate mounting bracket  181  secured to the footrest hanger  140  (for example, by a fastener installed through a mounting hole  182  in the bracket  181  aligned with selected holes  172  in the vertical portion  142  of the footrest hanger  140 ). As shown, the mounting bracket may include an enlarged U-shaped attachment portion  183  ( FIG. 3 ), to provide rigid support between the footrest hanger  140  and the mounting bracket  181 . In other embodiments (not shown), the mounting bracket attachment portion may be contoured or otherwise configured to allow the mounting bracket to be pivoted or folded upward, for example, to facilitate storage or transportation of the wheelchair. The mounting bracket  181  includes a concave spherical surface  184  sized and shaped to receive a ball portion  186  of a ball joint  185  ( FIGS. 3 and 5 ). As shown in  FIG. 5 , a stem portion  187  of the ball joint  185  is secured to the footrest plate  170 , such that the position of the footrest plate is adjustable by moving the ball joint  185  with respect to the mounting bracket  181 . While the stem portion  187  of the ball joint  185  may be affixed directly to the footrest plate  170 , in the illustrated embodiment, the stem portion  187  is affixed (e.g., welded) to an adapter plate  188 , which may be secured to the footrest plate  170  in a variety of positions, thereby allowing the lateral and/or longitudinal position of the footrest plate, with respect to the footrest hanger  140 , to be adjusted within a plane defined by the footrest plate. In the illustrated example, the footrest plate  170  includes mounting slots  179  that may be positioned with respect to corresponding mounting holes  189  in the adapter plate  188 , with mounting bolts or other suitable fasteners  178  ( FIGS. 4A-C ) installed through the aligned slots  179  and holes  189  to secure the footrest plate  170  in the selected position. As shown, the mounting slots  179  may be provided with chamfered edges for seating engagement with a chamfered head on the bolts. As shown, the footrest plate  170  may include additional mounting holes  177  for further attachment (e.g., with additional bolts) when aligned with corresponding mounting holes in the adapter plate  188 , and/or for attachment of other accessories, such as, for example, foot retaining straps or guards. 
     To secure the ball joint  185  in a selected position with respect to the footrest plate mounting bracket  181 , as shown in  FIG. 5 , a collar  195  or other suitable clamping member is assembled with the mounting bracket over the ball portion  186  of the ball joint  185 , thereby capturing the ball portion between the collar  195  and the mounting bracket. The collar  195  may, but need not, include a spherical concave surface  196  to closely receive the ball portion  186  of the ball joint. Fasteners  194  attaching the collar  195  to the mounting bracket  181  (through aligned mounting holes  193 ,  197 ) are tightened to apply a clamping or gripping force on the ball portion  186 , thereby securing the ball joint  185  against additional movement. To adjust the position of the ball joint  185  with respect to the mounting bracket  181 , the collar  195  is loosened (e.g., by loosening the fasteners) to reduce the gripping force on the ball portion  186 . As shown in  FIG. 3 , the collar may include a slotted portion  198  allowing the collar to be installed (and removed from) around the stem portion of the ball joint. 
     To improve the clamping grip on the ball portion  186 , at least an outer portion of the ball portion may be provided in a compressible material (e.g., a rubber coating), thereby providing for a more uniform grip between the ball portion and the concave spherical surfaces  184 ,  196  of the mounting bracket  181  and collar  196 . In another embodiment, a footrest assembly may additionally or alternatively include mounting bracket and/or collar concave surfaces that include compressible materials. 
     While various inventive aspects, concepts and features of the inventions may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects, concepts and features may be used in many alternative embodiments, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present inventions. Still further, while various alternative embodiments as to the various aspects, concepts and features of the inventions—such as alternative materials, structures, configurations, methods, devices and components, alternatives as to form, fit and function, and so on—may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the inventive aspects, concepts or features into additional embodiments and uses within the scope of the present inventions even if such embodiments are not expressly disclosed herein. Additionally, even though some features, concepts or aspects of the inventions may be described herein as being a preferred arrangement or method, such description is not intended to suggest that such feature is required or necessary unless expressly so stated. Still further, exemplary or representative values and ranges may be included to assist in understanding the present disclosure; however, such values and ranges are not to be construed in a limiting sense and are intended to be critical values or ranges only if so expressly stated. Moreover, while various aspects, features and concepts may be expressly identified herein as being inventive or forming part of an invention, such identification is not intended to be exclusive, but rather there may be inventive aspects, concepts and features that are fully described herein without being expressly identified as such or as part of a specific invention. Descriptions of exemplary methods or processes are not limited to inclusion of all steps as being required in all cases, nor is the order that the steps are presented to be construed as required or necessary unless expressly so stated.