Patent Publication Number: US-2005121873-A1

Title: Cart for injured person

Description:
FIELD OF THE INVENTION  
      The present invention relates the locomotion of a person having a non-ambulatory lower leg. More particularly, the invention relates to a cart for an injured person including a plurality of wheels that is moveable between a first asymmetrical position relative to the frame and a second asymmetrical position relative to the frame, thereby accommodating a person having a non-ambulatory lower left leg or a non-ambulatory lower right leg, respectively.  
     BACKGROUND  
      Various self-propelled carts, scooters, walkers, etc. for the locomotion of a person who has one non-ambulatory lower leg and one ambulatory leg are known. Typically, the person rests his or her non-ambulatory lower leg on a surface supported by a wheeled frame, while using his or her ambulatory leg for propulsion.  
      A problem with such devices has been their instability. In short, they have been undesirably prone to tipping over during operation. Another problem with such devices has been their lack of versatility. Devices made specifically for a person having a non-ambulatory lower left leg have not been suitable for a use by person having a non-ambulatory lower right leg, and vice-versa. Prior devices have not fully addressed both of these issues.  
      For example, U.S. Pat. No. 5,800,317 to Accetta (“Accetta”) discloses a four-wheeled walker with a side extension that serves as an outrigger to give the wheels of the walker an asymmetrical arrangement relative to a center axis of the vehicle. Accetta is directed to the instability problem, but the walker that Accetta teaches lacks versatility, as it is dedicated to either a left or a right leg.  
      Meanwhile, U.S. Pat. No. 5,839,740 to Seeger (“Seeger”) discloses a three-wheeled cart. The two front wheels of the cart are fixed. The rear (third) wheel is attached to a leg support assembly that is configured to be attached to either a left or a right side of the cart. This allows reconfiguration of the cart to accommodate either a left or a right leg, but the three-wheeled cart is inherently less stable than a four-wheeled vehicle.  
      There is, therefore, a need for a stable, yet versatile cart for an injured person.  
     SUMMARY OF THE INVENTION  
      The present invention provides a cart for an injured person. The cart includes a frame, a leg support member coupled to the frame, and a plurality of wheels coupled to the frame. The plurality of wheels is moveable between a first asymmetrical position relative to the frame and a second asymmetrical position relative to the frame, thereby accommodating a person having a non-ambulatory lower left leg or a non-ambulatory lower right leg, respectively.  
      The above-noted features and advantages of the present invention, as well as additional features and advantages, will be readily apparent to those skilled in the art upon reference to the following detailed description and the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of a person operating a cart according to the present invention;  
       FIG. 2  is a front view of a cart having an alternative handlebar according to the present invention;  
       FIG. 3  is a front view of a cart having another alternative handlebar according to the present invention;  
       FIG. 4  is a front view of yet another alternative handlebar according to the present invention;  
       FIG. 5  is a bottom view of the cart of  FIG. 1  with wheels positioned to accommodate a person having a non-ambulatory lower left leg and an ambulatory right leg;  
       FIG. 6  is a bottom view of the cart of  FIG. 1  with wheels positioned to accommodate a person having a non-ambulatory lower right leg and an ambulatory left leg;  
       FIG. 7  is a front view of the cart of  FIG. 1  with its leg support and handlebar in lowered positions;  
       FIG. 8  is a front view of the cart of  FIG. 1  with its leg support and handlebar in raised positions;  
       FIG. 9  is a side view of the cart of  FIG. 1  with its leg support in a lowered position and its handlebar in a lowered position; and  
       FIG. 10  is a is a side view of the cart of  FIG. 1  with its leg support in a raised position and its handlebar in a lowered position.  
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS  
       FIG. 1  is a perspective view of a person  2  operating a cart  3  according to the present invention. Cart  3  includes a frame  4 , a leg support  14 , a left front wheel  22 , a right front wheel  24 , a left vertical axle  26 , a right vertical axle  27 , a left horizontal axle  29 , a right horizontal axle  30 , a first rear wheel  32 , a second rear wheel  34 , a left horizontal axle  36 , a right horizontal axle  38 , a coupling bar  40 , an upper coupling flange  42 , a lower coupling flange  46 , a bolt  50 , a handlebar  54 , a handgrip  66 , a handgrip  70 , a handbrake  74 .  
      As shown in  FIG. 1 , frame  4  provides general support to the cart similar to the support typically provided by a bicycle or tricycle frame. Accordingly, frame  4  may be manufactured from the same materials and with the same type of equipment used in the production of similar devices such as scooters, tricycles, wheelchairs, shopping carts, walkers, etc. In the exemplary embodiment described herein, frame  4  is made from sections of steel tubing that are suitably bent into shape and welded together. The steel tubing is thin walled cold rolled steel. If desired, ends of the tubing may be capped by a plastic or metal plug for strength. Alternatively, frame  4  may be constructed from carbon fibers, aluminum, titanium, chrome molly, stainless steel, or any other suitable material.  
      Frame  4  includes a substantially T-shaped base  5 , which is formed by a longitudinal bar  6  that is welded to a transverse bar  7 . Remote from the connection of longitudinal bar  6  and transverse bar  7 , longitudinal bar  6  has a substantially planar or substantially flat end  8 . At a transverse midpoint  9  of transverse bar  7 , frame  4  includes an anterior sleeve  10  that is welded to transverse bar  7  and extends upwards therefrom. At a site  11  on longitudinal bar  6  that is spaced apart from substantially flat end  8  but closer to substantially flat end  8  than to transverse bar  7 , frame  4  includes a posterior sleeve  12  that is welded to longitudinal bar  6  and extends upwards therefrom.  
      Leg support  14  supports a user&#39;s non-ambulatory lower leg in operation as discussed in further detail below. The interior structure (not shown) of leg support  14  may be extruded aluminum, molded plastic, carbon fibers, or aluminum, stainless steel, steel plate, or any other suitable material. The exterior of leg support  14  is padded with foam rubber or any other suitable material and is covered with vinyl or any other suitable material. Additionally, leg support  14  includes a roughly concave surface  16  for encouraging centering of the non-ambulatory lower leg. Further, leg support  14  includes a tubular member or post  18  (see  FIG. 7 ,  FIG. 8 ,  FIG. 9 , and  FIG. 10 ) which extends downward into posterior sleeve  12  of frame  4  for securing leg support  14  to frame  4  in a manner similar to that of the typical attachment of a bicycle seat to a bicycle frame. The engagement between leg support  14  and frame  4  may include a quick disconnect mechanism  20  such as, for example, a cam operated pinch lock, to facilitate adjustments to the height of leg support  14  (see  FIG. 7 ,  FIG. 8 ,  FIG. 9 , and  FIG. 10 ). Various ways of implementing suitable quick disconnect arrangements are well known.  
      Left front wheel  22  and right front wheel  24  help facilitate propulsion and maneuvering of cart  3 . Accordingly, left front wheel  22  and right front wheel  24  are rotatable wheels, preferably in the form of castors. As such, left front wheel  22  and right front wheel  24  preferably have a respective left vertical axle  26  and right vertical axle  27  where they are attached to the frame  4  and a respective left horizontal axle  29  and right horizontal axle  30  from which the wheel of the castor rotates. To enhance the aesthetics of the cart  3 , the upward facing ends of left vertical axle  26  and right vertical axle  27  may be covered with finishing plugs. In the embodiment shown in  FIG. 1 , left front wheel  22  and right front wheel  24  are positioned symmetrically relative to the frame; that is, they are roughly equidistant from longitudinal bar  6  and anterior sleeve  10 .  
      Left front wheel  22  and right front wheel  24  each has a pliable tire and is of such size and construction that no heavy resistance is encountered when the wheels are rotated on flat ground or slightly uneven surfaces such as grass or gravel. The tires may be made of rubber, thermoplastic rubber, super tough nylon, or any other suitable material and they may be pneumatic or non-pneumatic. It should be appreciated that the non-marking type tires typically used on wheelchairs should be suitable for this application.  
      First rear wheel  32  and second rear wheel  34  also help facilitate propulsion and maneuvering of cart  3 . First rear wheel  32  and second rear wheel  34  are rotatable wheels, however, in the exemplary embodiment they are not castors. Accordingly, first rear wheel  32  and second rear wheel  34  have a respective left horizontal axle  36  and right horizontal axle  38  about which they rotate, but they do not have vertical axles. Nevertheless, it is noted that in alternative embodiments, first rear wheel  32  and second rear wheel  34  may be castors. Further, it is noted that alternative embodiments of cart  3  may include more or less than two rear wheels. In any event, first rear wheel  32  and second rear wheel  34  have tires as discussed above in connection with left front wheel  22  and right front wheel  24 .  
      Coupling bar  40  extends laterally between first rear wheel  32  and second rear wheel  34  as shown. Coupling bar  40  includes a substantially planar or substantially flat side  41  that abuts substantially flat end  8  of longitudinal bar  6 . Upper flange  42  and lower flange  46  are planar, substantially T-shaped pieces which are welded to longitudinal bar  6  of frame  4  in proximity to substantially flat end  8  of frame  4 . Upper flange  42  and lower flange  46  extend over and under coupling bar  40 , respectively, to effectively sandwich coupling bar  40  and secure it (and thus, first rear wheel  32  and second rear wheel  34 ) vertically relative to frame  4 . It is noted that in the embodiment shown in  FIG. 1 , upper flange  42  and lower flange  46  do not wrap behind coupling bar  40 . When installed, bolt  50  extends through apertures in upper flange  42 , coupling bar  40 , and lower flange  46  (in  FIG. 1 , bolt  50  occupies the apertures) into a hex nut (not shown), thereby securing coupling bar  40  (and thus, first rear wheel  32  and second rear wheel  34 ) to frame  4  in a horizontal plane roughly defined by longitudinal bar  6  and transverse bar  7 . Accordingly, it should be appreciated that coupling bar  40  is removably coupled to frame  4  by upper flange  42 , lower flange  46 , and bolt  50 . To this end, removing bolt  50  frees coupling bar  40  to be pulled rearwardly away and separated from frame  4  (see directional arrow  86  of  FIG. 5  and  FIG. 6 ). Further, it should be appreciated that because the aperture in coupling bar  40  which receives bolt  50  is not equally spaced between first rear wheel  32  and second rear wheel  34  (i.e., it is offset, or closer to one of the wheels than the other), coupling bar  40  asymmetrically mounts first rear wheel  32  and second rear wheel  34  to frame  4 . In other words, when coupling bar  40  is secured to frame  4 , one of first rear wheel  32  and second rear wheel  34  is laterally closer to leg support  14  than the other (see also  FIG. 5  and  FIG. 6 , discussed below). In any event, it is noted that the embodiments shown in the figures are merely exemplary, and the asymmetrical mounting may be suitably implemented with quick disconnect mechanisms rather than bolt  50 , with sliding engagements or tracks that allow for repositioning of first rear wheel  32  and second rear wheel  34  without substantially separating them from frame  4 , or in any other suitable manner. Additionally, it should be appreciated that in alternative embodiments coupling bar  40  may couple any of a wide number of wheels to frame  4  in addition to or in lieu of first rear wheel  32  and second rear wheel  34 , some of which it may couple to frame  4  in a substantially symmetrical manor. It should be appreciated, however, that because the position of the aperture in coupling bar  40  (that receives bolt  50 ) is fixed relative to first rear wheel  32  and second rear wheel  34 , the embodiment shown in  FIG. 1  provides predetermined positioning of first rear wheel  32  and second rear wheel  34  relative to frame  4 , which ensures that these wheels are properly positioned for stability and reduces setup time.  
      Referring still to  FIG. 1 , handlebar  54  includes a tubular member or post  58  (see  FIG. 7  and  FIG. 8 ) which extends downward into anterior sleeve  10  of frame  4  for securing handlebar  54  to frame  4  in a manner similar to that of the typical attachment of bicycle handlebar to a bicycle frame. The engagement between handlebar  54  and frame  4  may include a quick disconnect mechanism  62  such as, for example, a cam operated pinch lock, to facilitate adjustments to the height of handlebar  54  (see also  FIG. 7 ,  FIG. 8 ,  FIG. 9 , and  FIG. 10 ). Further, it should be appreciated that quick disconnect mechanism  62  also allows handlebar  54  to be easily loosened and rotated 180 degrees about a vertical axis (roughly defined by anterior sleeve  10 ) to position handbrake  74  (handbrake  74  is discussed in further detail below) for operation by either a left hand or a right hand of person  2 . Various ways of implementing suitable quick disconnect arrangements are well known.  
      To ensure a secure grip, handgrip  66  and handgrip  70  handlebar  54  are fitted onto handlebar  54 . Handgrip  66  and handgrip  70  are made from rubber or any other suitable material. In the embodiment shown in  FIG. 1 ,  FIG. 5 ,  FIG. 6 ,  FIG. 7 ,  FIG. 8 ,  FIG. 9 , and  FIG. 10 , handlebar  54  is symmetrically mounted to frame  4 . In other words, handgrip  66  and handgrip  70  are substantially laterally equidistant from tubular member or post  58 . To positively brake cart  3 , handbrake  74  is attached to handlebar  54 . Handbrake  74  includes an operating lever  78  attached to a distal end of handlebar  54 , and a brake cable  82  that couples operating lever  78  to an associated brake caliper (not shown). The caliper grips opposing sides of right front wheel  24  to brake cart  3  when the operating lever  78  is activated, as is well known with these types of brakes. It should be appreciated that while only one brake is shown, cart  3  may be configured with two brakes, one attached to each end of handlebar  54 , in which case the additional calipers may be applied to the other front wheel. Furthermore, it should be readily appreciated that in the case of one brake, the brake may be suitably coupled to either end of handlebar  54  and may be applied to either front wheel.  
       FIG. 2  is a front view of a cart  200  having an alternative handlebar  220  according to the present invention. Aside from handlebar  220 , the remaining components of cart  200  are identical to the corresponding components of cart  3  (see  FIG. 1 ). Here, it is noted that in the embodiment shown in  FIG. 1  the symmetrical mounting of handlebar  54  may result in a slight degree of undesirable lateral shifting of the upper body of person  2  relative to the lower body of person  2 , as person  2  does not actually straddle leg support  14  (which differs somewhat from the manner is which one typically sits on a bicycle, where the handlebars and the seat are typically more in alignment). Handlebar  220  includes a substantially vertical tubular member or post  230  that extends downward into anterior sleeve  10  of frame  4  for securing handlebar  220  to frame  4  in a manner similar to the typical attachment of bicycle handlebar to a bicycle frame. However, contrary to handlebar  54  ( FIG. 1 ), handlebar  220  is asymmetrically mounted to frame  4 . In other words, handgrip  70  is laterally closer to post  230  than handgrip  66 . This asymmetrical mounting may shift the upper body of person  2  to compensate somewhat for not actually straddling leg support  14 . Additionally, asymmetrically mounted handlebar  220  may provide accommodation for a person who may favor either his or her left or right upper body due to illness or injury. It should be appreciated that quick disconnect mechanism  62  facilitates adjustments to the height of handlebar  220 , and allows handlebar  220  to be rotated 180 degrees about a vertical axis (roughly defined by anterior sleeve  10 ) for moving handlebar  220  between a first predetermined position which may tend to shift the upper body to the left and a second predetermined position which may tend to shift the upper body to the right (see directional arrows  240 ).  
       FIG. 3  is a front view of a cart  300  having another alternative handlebar  320  according to the present invention. Aside from handlebar  320 , the remaining components of cart  300  are identical to the corresponding components of cart  3  ( FIG. 1 ). As noted above in connection with  FIG. 2 , the symmetrical mounting of handlebar  54  may result in a slight degree of undesirable lateral shifting of the upper body of person  2 . Handlebar  320  includes a first tubular member or post  330  that extends downward towards frame  4 , and a second tubular member or post  340  that extends downward into anterior sleeve  10  of frame  4  for securing handlebar  320  to frame  4  in a manner similar to the typical attachment of bicycle handlebar to a bicycle frame. First post  330  is separated from second post  340  by a lateral spacer portion  350 . As a result, handlebar  320  is asymmetrically mounted to frame  4 . It should be readily appreciated that quick disconnect mechanism  62  facilitates adjustments to the height of handlebar  320 , and allows handlebar  320  to be rotated 180 degrees about a vertical axis (roughly defined by anterior sleeve  10 ) for moving handlebar  320  between a first predetermined position which may tend to shift the upper body to the left and a second predetermined position which may tend to shift the upper body to the right (see directional arrows  360 ).  
       FIG. 4  is a front view of yet another alternative handlebar  420  according to the present invention. It should be appreciated that handlebar  420  may be substituted for handlebar  54  in cart  3  (see  FIG. 1 ). As noted above in connection with  FIG. 2  and  FIG. 3  above, the symmetrical mounting of handlebar  54  may result in a slight degree of undesirable lateral shifting of the upper body of person  2 . Handlebar  420  includes a tubular member or post  430  that extends downward for insertion into anterior sleeve  10  of frame  4  in order to secure handlebar  420  to frame  4  in a manner similar to the typical attachment of bicycle handlebar to a bicycle frame (frame  4  is not shown in  FIG. 4 ). Post  430  defines a transverse passageway  440  that is roughly perpendicular to post  430 . Handlebar  420  further includes a crossbar  450  that extends through passageway  440  and is secured therein by a quick disconnect mechanism  460  or any other suitable device. Handgrip  66  and handgrip  70  are fitted onto crossbar  450 . Quick disconnect mechanism  62  (see  FIG. 1 ) facilitates adjustments to the height of handlebar  420 . Meanwhile, operation of quick disconnect mechanism  460  allows crossbar  450  to be moved from side to side (see linear directional lines  470 ) between a virtually infinite number of positions which may be used to shift the upper body to the left or to the right.  
       FIG. 5  is a bottom view of cart  3  (see also  FIG. 1 ) with first rear wheel  32  and second rear wheel  34  positioned to accommodate a person having a non-ambulatory lower left leg and an ambulatory right leg. Adjusting cart  3  to this state may require removing bolt  50 , pulling coupling bar  40  away from frame  4  in the direction of directional arrow  86 , flipping or rotating coupling bar  40  180 degrees in the direction of directional arrow  90  ( FIG. 6 ), and re-securing coupling bar  40  to frame  4  with bolt  50 .  
       FIG. 6  is a bottom view of cart  3  (see also  FIG. 1 ) with first rear wheel  32  and second rear wheel  34  positioned to accommodate a person having a non-ambulatory lower right leg and an ambulatory left leg. Adjusting cart  3  to this state may require removing bolt  50 , pulling coupling bar  40  away from frame  4  in the direction of directional arrow  86 , flipping or rotating coupling bar  40  180 degrees in the direction of directional arrow  94  ( FIG. 5 ), and re-securing coupling bar  40  to frame  4  with bolt  50 .  
      After the user ensures that first rear wheel  32  and second rear wheel  34  are appropriately positioned, the user adjusts the height of leg support  14  and handlebar  54  by disengaging quick disconnect mechanism  20  and quick disconnect mechanism  62 , respectively, moving leg support  14  and handlebar  54  as desired, and re-engaging quick disconnect mechanism  20  and quick disconnect mechanism  62 .  
       FIG. 7  is a front view of cart  3  with leg support  14  and handlebar  54  in lowered positions, and  FIG. 8  is a front view of the cart  3  with leg support  14  and handlebar  54  in raised positions. Here, it is noted that although  FIG. 7  and  FIG. 8  show both leg support  14  and handlebar  54  in lowered and raised positions, respectively, leg support  14  and handlebar  54  may be adjusted independently of one another. For example,  FIG. 9  is a side view of cart  3  with leg support  14  in a lowered position and handlebar  54  in a lowered position, while  FIG. 10  is a is a side view of cart  3  with leg support  14  in a raised position and handlebar  54  in a lowered position. Further, it should be readily appreciated that the in the embodiment shown in  FIG. 1 , the user is not restricted to just one lowered and one raised position. Similar to adjusting a typical bicycle seat or bicycle handlebar, such adjustments may be made with practically infinite resolution.  
      For locomotion, the user places the non-ambulatory lower leg on the leg support  14 , places hand(s) on handgrip  66  and/or handgrip  70 , and scoots cart  3  with the ambulatory leg (see  FIG. 1 ). Accordingly, the user moves about, steering cart  3  by exerting various upper body forces on handlebar  54  and/or by exerting various lower body forces on leg support  14 . Braking is applied by activating handbrake  74  as necessary. Further, the user maneuvers cart  3  over door thresholds or similar obstacles while still supporting the non-ambulatory lower leg simply by lifting up on handlebar  54  to clear the obstruction. Thus, it should be appreciated that cart  3  may be used on most reasonably level surfaces and moderate inclines. It may also be used on slightly uneven surfaces such as grass or gravel as handlebar  54  may be used to lift or pull cart  3  forward with each stride. It should be appreciated that cart  200  ( FIG. 2 ) and cart  300  ( FIG. 3 ) are operated in a similar fashion to cart  3 , with the added adjustment of the asymmetrical position of handlebar  220  and handlebar  320 , respectively, as desired.  
      The foregoing description of the invention is illustrative only, and is not intended to limit the scope of the invention to the precise terms set forth. Further, although the invention has been described in detail with reference to certain illustrative embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.