Abstract:
A footrest apparatus for a wheelchair and the like has a pair of supporting frame configurations supporting a pair of foot plates to be position in a first position for use and a second position for transportation and/or storage. Each of the supporting frame configurations has a connecting shaft rotatably received in a vertical tube of a front wheel assembly. The vertical tube is affixed to a frame structure of the wheelchair and the like. The connecting shaft and the vertical tube in combination bear and transfer a foot load of the user and therefore a locking device provided between the connecting shaft and the vertical tube for locking the connecting frame configuration in a selected one of the first and second positions, will not bear the foot load, resulting a configuration convenience for conducting an unlock action.

Description:
TECHNICAL FIELD 
     The described subject matter generally relates to a device for assisting a user with mobility, such as a wheelchair or a rolling walker having a seat and being convertible to a temporary transportation tool, and more particularly to a footrest apparatus of a wheelchair and the like. 
     BACKGROUND OF THE ART 
     A wheelchair or a rolling walker convertible to a temporary transportation tool, is commonly used as a device for assisting elderly, handicapped people or patients, with mobility. Such a wheelchair or the like, conventionally has a frame structure in either a fixed or collapsible configuration, supported on a plurality of wheels rotatably attached to the frame structure. A seat member and a footrest apparatus are typically provided to support a user sitting on the wheelchair or the like. The footrest apparatus may be rotatable or moveable between an extended position in which the foot plates are positioned in front of the frame structure to support the user&#39;s feet when the user sits on the wheelchair or the like, and a folded position in which the footrest apparatus is positioned close to the frame structure when the footrest apparatus is not in use, for convenience of transportation and/or storage of the wheelchair and the like. Various configurations of footrest apparatuses are known, however efforts for development of footrest apparatuses continues in order to provide wheelchairs or the like having a footrest apparatus which is more convenient for use. 
     Accordingly there is a need for a device having an improved footrest apparatus for assisting an individual with mobility. 
     SUMMARY 
     In accordance with one aspect, there is provided a device for assisting a user with mobility, comprising: a frame structure supported on a plurality of wheels rotatably attached to the frame structure, a seat member attached to the frame structure and a pair of footrest assemblies, each of the footrest assemblies including a supporting frame configuration supporting a foot plate, each of the supporting frame configurations including a connecting shaft rotatably inserted downwardly into an upper end of a respective one of a pair of vertical tubes affixed to a front end and at respective sides of the frame structure, to allow the supporting frame configuration to rotate about said one of the vertical tubes between a first angular position in which the supporting frame configuration extends forwardly to position the foot plate in front of the frame structure and a second angular position in which the supporting frame configuration is folded backward and adjacent a side of the frame structure, each of the connecting shafts having an annular radial shoulder resting on an annular surface of the upper end of the vertical tube to support a foot load, each of the connecting shafts including two elastically compressible spring-buttons, at least one of the spring-buttons being compressed radially inwardly into the connecting shaft by a cylindrical inner surface of the vertical tube when the supporting frame configuration is in any angular position about the vertical tube, and only one of the spring-buttons radially and outwardly extending from the connecting shaft into a hole in the vertical tube when the supporting frame configuration is in either one of the first and second angular positions. 
     Other aspects and features of the described subject matter will be better understood with reference to the embodiments described hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Reference will now be made to the accompanying drawings, showing by way of illustration, the described subject matter, in which: 
         FIG. 1  is an isometic view of a device for assisting a user with mobility according to one embodiment, having a footrest apparatus in an extended position, one footrest being disconnected from a frame structure of the device, showing the connection therebetween; 
         FIG. 2  is an isometric view of the device of  FIG. 1  with the footrest apparatus in a folded position, one footrest being disconnected from the frame structure of the device to show the connection therebetween; and 
         FIG. 3  is a partial side elevational view of a device for assisting a user with mobility according to another embodiment in which a footrest similar to the footrest of  FIGS. 1 and 2 , is connected to a frame structure different from the embodiment of  FIG. 1 . 
     
    
    
     It will be noted that throughout the appended drawings, like features are identified by like reference numerals. 
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1-3 , a device  10  for assisting a user with mobility, such as a rolling walker described in the Applicant&#39;s U.S. Pat. Nos. 7,523,950 and 7,628,411, which are incorporated herein by reference, generally includes a frame structure  12  preferably made of metal tubes supported on a plurality of wheels  13  rotatably attached to the frame structure  12 . According to this embodiment, four wheels  14  are used to support the device for moving along a ground surface. 
     The frame structure  12  has two sides symmetrical about a central vertical plane (not shown). For clarity and convenience of illustration, components which are identical on the respective sides of the device or the frame structure  12  will be identified only on one of the sides. 
     According to one embodiment, the frame structure  12  may include two front legs  14  disposed substantially vertically on the respective sides thereof, each front leg  14  having an upper end  16  and a lower end  18  thereof. The frame structure  12  may further include two rear legs  20  disposed substantially vertically on the respective sides thereof, each rear leg  20  having a lower end  24  and an upper end (not shown) which may be formed with a handle for grasping by a caregiver. The rear legs  20  are longer than the front legs  14 . A pair of middle side tubes  26  may be provided, one on each side of the frame structure  12  such that a front end of the middle side tube  26  is affixed for example by welding to the respective front leg  14  adjacent to the upper end  16 , and a rear end of the middle side tube  26  is affixed for example by welding to a middle portion (not numbered) of the respective rear leg  20 . Each middle side tube  26  may extend substantially horizontally when the device  10  is supported on a level surface. A pair of upper side tubes  28  may be positioned, one on each side of the frame structure  12 , above the respective middle side tube  26 , substantially parallel to and slightly spaced apart from the middle side tube  26 . Each upper side tube  28  may have a rear end affixed for example by welding to the middle portion of the respective rear leg  20 . An elbow connector (not shown) which is used to interconnect end-to-end, two tubes oriented to each other at a right angle, may be provided to connect a front end  30  of each upper side tube  28  to the upper end  16  of the respective front leg  14 . 
     A pair of low side tubes  32  may be provided, one on each side of the frame structure  12 , positioned substantially parallel to the respective middle and upper side tubes  26 ,  28 . Each low side tube  32  may be affixed at a rear end portion (not numbered) thereof to the low end  24  of the respective rear leg  20 . A pair of L-shaped front connecting tubes  34  may be provided, one on each side of the frame structure  12 , each having a vertical section (not numbered) extending downwardly to be affixed for example by welding to a front end section  36  of the respective low side tube  32 , and having a substantially horizontal section (not numbered) extending forwardly to be affixed for example by welding to the lower end  18  of the respective front leg  14 . Therefore, the L-shaped front connecting tube  34  on each side of the frame structure  12  provides a space for the respective wheel  13  supported on the respective front leg  14 , to change directions without interference with the frame structure  12 . 
     A pair of interconnecting tubes  38  may be provided to interconnect the two sides of the frame structure  12  together. Each interconnecting tube  38  may be affixed at an upper end (not numbered) thereof, for example by welding to a middle section of one upper side tube  28  and affixed at a low end (not numbered) thereof, for example by welding to the low side tube  32  at the opposed side of the frame structure  12 . The low end of the interconnecting tubes  38  may be connected to the respective low side tube  32  at a location close to the front end portion  36  thereof. 
     A seat member such as a piece of fabric or leather, indicated by broken lines  40  may be provided, attached to the respective upper side tubes  28  such that a user of the device  10  may sit on the seat member  40 . A piece of fabric or leather (not shown) may be attached to the respective rear legs  20  and positioned above the seat member  40  to form a backrest of the device  10 . 
     According to one embodiment, two of the wheels  13  may be positioned one on each side of the frame structure  12 , and rotatably mounted, for example to the respective low side tube  32  at a location where the low end  24  of the rear leg  20  joins the low side tube  32 . Two of the wheels  13  positioned one on each side and at a front location of the device  10 , may be mounted to a respective support fork member  42  which has a fork shaft  44  (see  FIG. 3 ) received in a vertical tube, for example a fort tube  46 . The fork tube  46  may be positioned substantially vertical and affixed, for example through a bracket  48  by welding, to the respective front leg  14  as shown in  FIGS. 1 and 2 . 
     According to another embodiment as shown in  FIG. 3 , the frame structure  12  may be configured differently from the frame structure  12  as shown in  FIGS. 1 and 2  such that the fork tube  46  is affixed, for example by welding to a front end (not numbered) of the low side tube  32   a  at each side of the frame structure  12 . 
     The fork shaft  44  may be inserted through a lower end of the fork tube  46  and held in position within the fork tube  46  to allow the support fork member  42  with the wheel  13  supported thereon, to rotate about the fork shaft  44  with respect to the fork tube  46 . The support fork member  42  may extend from the fork shaft  44 , downwardly in an angular orientation with respect to the vertical direction, such that the wheel  13  supported on the support fork member  42  may pivot together with the support fork member  42  about the fork tube  46  to change a rolling direction of the wheels. This type of wheel assembly is well known and will not be further described herein. 
     The device  10  may further include a pair of foot rest assemblies positioned one on each side of the front of the device  10 . Each foot rest assembly may have a supporting frame configuration  50  which supports a foot plate  52 . Each of the supporting frame configurations  50  may include a connecting shaft  54  rotatably inserted downwardly into an upper end of the respective fork tube  46  to allow the supporting frame configuration  50  to rotate about the fork tube  46  between a first angular position as shown in  FIG. 1  and a second angular position as shown in  FIG. 2 . In the first angular position the supporting frame configuration  50  may extend forwardly to place the foot plate  52  at the front of the frame structure  12 . In the second angular position the supporting frame configuration  50  may be folded backward to be positioned adjacent to the respective side of the frame structure  12 . The supporting frame configuration  50  of the footrest assembly at the left side of the frame structure  12  in  FIGS. 1 and 2 , for convenience of description and illustration only, is positioned such that the connecting shaft  54  thereof is withdrawn upwardly from the fork tube  46 , in order to illustrate the details of the connection therebetween, which are further described hereinafter. 
     Each of the connecting shafts  54  may be formed with an upper section  56  (see  FIG. 3 ) having an outer diameter greater than an outer diameter of a lower section  58  of the connecting tube  54 , thereby defining an annular radial shoulder  60  resting on an annular surface  62  defined on an upper end of the fork tube  46 . Therefore, when the footrest assembly is positioned as illustrated in  FIG. 1  and a user sits on the seat member  40  with his/her feet resting on the foot plates  52 , the user&#39;s foot load is substantially transferred through the contact between the annular radial shoulders  60  of the connecting shaft  54  and the annular surface  62  of the upper end of the fork tube  46 , and thus to the frame structure  12  of the device  10 . 
     According to one embodiment each of the supporting frame configurations  50  may have a substantially inverted U-shaped tube  66  having two end sections  68 ,  70 , with one end section  68  (see  FIG. 3 ) longer than the other section  70 . A connecting bar  72  which may also be made of a metal tube, may extend between and be affixed for example by welding, to the longer end section  68  and the shorter end section  70  of the inverted U-shaped tube  66 . The short end section  70  may be affixed for example by welding through a short arm  74  (see  FIGS. 1 and 2 ) to the upper section of the connecting tube  54 . An inner tube  76  may be slidably received in the longer end section  68  (which forms an outer tube) of the inverted U-shaped tube  66  to form a telescoping configuration such that the length of the inner tube  76  extending from the outer tube (the inverted U-shaped tube  66 ) may be selected and locked by a locking device which, for example in this embodiment, may include a pair of diametrically opposed spring-buttons  78  (see  FIG. 3 ) projecting radially outwardly from the inner tube  76  and selectively engaged in one pair of a plurality of pairs of diametrically opposed holes  80  defined in the longer end section  68  of the inverted U-shaped tube  66 . Each of the supporting frame configurations  50  further may further include a plate shaft  64  connected to a lower end of the inner tube  76 , extending forwardly when the supporting frame configuration  50  is in the first angular position as shown in  FIG. 1 . A foot plate lock device (not numbered) may be provided, for example detachably interconnecting each foot plate  52  with one of the inner tubes  56  when the foot plate  52  is in the extended position, as illustrated in  FIG. 1 . 
     The foot plates  52  may be pivotally connected to and thus pivotable about the respective plate shafts  64  between an extended position as illustrated in  FIG. 1  in which the respective foot plates  52  extend from the respective plate shafts  64  toward each other substantially transverse with respect to the frame structure  12  (when the respective supporting frame configurations  50  are in the first angular position), and a folded position as illustrated in  FIG. 2  in which the foot plates  52  extend substantially upwardly from the respective plate shafts  64  (when the respective supporting frame configuration  50  is in any angular position such as in the second angular position). 
     In accordance with one embodiment, each of the footrest assemblies may be provided with a locking device (not numbered) for selectively locking the support frame configurations  50  in either one of the first and second angular positions. The locking device may include two elastically compressible spring-buttons  82  attached to the lower section  58  of the connecting shaft  54 . The two spring-buttons  82  may be angularly spaced apart on the lower section  58  of the connecting shaft  54 , for example diametrically opposed to each other, and radially outwardly extend from the lower section  58  of the connecting shaft  54 . Each of the spring-buttons  82  may be pressed radially inwardly into the cylindrical wall of the lower section  58  of the connecting shaft  54  and will return to the radially outwardly projecting position when the pressing force is removed. The locking device may further include only one positioning hole  84  defined in the fork tube  46 , penetrating the cylindrical wall of the fork tube  46  only once, such that only one of the two spring-buttons  82  on the lower section  58  of the connecting shaft  54  may be selectively engaged in the positioning hole  84 . Therefore, at least one of the spring-buttons  82  will be compressed radially inwardly into the connecting shaft  54  by a cylindrical inner surface of the fork tube  46  when the supporting frame configuration  50  is in any angular position about the fork tube  46  (including the first and second angular positions), and only one of the spring-buttons  82  will radially and outwardly extend from the connecting shaft  54  into the positioning hole  84  in the fork tube  46  when the supporting frame configuration  50  is in either the first or second angular position. 
     It should be noted that the structural arrangement and functions of the button-hole locking device formed with the spring-buttons  82  and the only one positioning hole  84  are different from those of the button-hole locking device formed by a pair of spring-buttons  78  selectively engageable with the pairs of diametrically opposed holes  80  in the longer section  68  of the inverted U-shaped tube  66 . The latter not only locks the height adjustment positions of the foot plates  52 , but also substantially bears and transfers the foot load and as such, requires a symmetrical arrangement of the button-hole engagement about the inner tube  76  and the lower section  68  of the U-shaped tube  66  to transfer and bear the foot load in a balanced manner such that two spring buttons  78  are simultaneously engageable with a pair of selected diametrically opposed holes  80 . 
     The locking device formed with two spring buttons  82  on the connecting shaft  54  and the only one positioning hole  84  in the fork tube  46  does not bear or transfer foot load which is supported by and transferred through the radial shoulder  60  on the connecting tube  54  and the annular surface  62  of the top end of the fork tube  46 . Therefore, this button-hole engagement does not require a symmetrical arrangement about the connecting shaft  54  and the fork tube  46 . The only one positioning hole  84  advantageously provides convenience for unlocking the supporting frame configuration  50  from either one of the first and second angular positions because pressing the spring-button  82  radially inwardly can be conducted through the only one positioning hole  84 . The only one positioning hole  84  is defined in the fork tube  46  which is affixed to the frame structure  12  and does not change its angular position regardless of the angular position of the supporting frame configuration  50 . This makes it possible to unlock the spring-button  82  from the positioning hole  84  in the same location, regardless of the first or second angular position in which the supporting frame configuration  50  is locked. This is advantageous because the fork tube  46  in which the positioning hole  84  is defined, is welded side-by-side to the respective front leg  14  and is in an area crowded with footrest components. The positioning hole  84  may be advantageously defined in a location at an outermost side of the respective fork tube  46 . The angular position of the two spring-buttons  82  attached to the lower section  58  of the connecting tube  54 , depends on the angular relationship between the first and second angular positions of the supporting frame configuration  50  (the footrest assembly). If the supporting frame configuration  50  requires 180 degree rotation between the first and second angular positions, the two spring-buttons  82  attached to each connecting shaft  54  may be diametrical opposed about the connecting shaft  54 . Otherwise, the two spring-buttons  82  attached to the respective connecting shaft  54  may be angularly spaced in accordance with the required rotation degree of the support frame configuration  50  (the footrest assembly) between the first and second angular positions. 
     Modifications and improvements to the above-described embodiments of the present invention may become apparent to those skilled in the art. For example, the frame structure of the device may vary from the above-described configuration. The foregoing description is intended to be exemplary rather than limiting. The scope of the present invention is therefore intended to be limited by the scope of the appended claims.