Patent Publication Number: US-10307314-B2

Title: Modular wheelchair system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This is a Continuation-in-part application based upon U.S. non-provisional patent application Ser. No. 15/287,290, entitled “MODULAR WHEELCHAIR SYSTEM”, filed Oct. 6, 2016, which is incorporated herein by reference. patent application Ser. No. 15/287,290, is a non-provisional application based upon U.S. provisional patent application Ser. No. 62/237,658, entitled “MODULAR WHEELCHAIR SYSTEM”, filed Oct. 6, 2015. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to wheelchairs, and, more particularly, to wheelchairs that are adaptable to other healthcare uses. 
     2. Description of the Related Art 
     Wheelchairs typically incorporate a seat, foot rests and four wheels. There are usually two caster wheels at the front and two large wheels at the back of the chair. The two larger wheels in the back usually have hand rims that have a diameter normally only slightly smaller than the wheels they are attached to, and are present to allow the occupant to grasp and propel the chair. Most wheelchairs also have two handles at the top of the back to allow for manual propulsion of the chair by another person. 
     Other wheelchairs are variations on this basic design, but they can be customized to meet the user&#39;s needs. Seat dimensions, height of the chair, seat angle, footrests, leg rests, front caster outriggers and adjustable backrests are all items that can be customized. Additionally, propulsion and control systems can be added to allow mobility to those that have limited use of their arms. 
     Wheelchairs come in two major designs—folding or rigid. The rigid chairs have permanently welded joints and fewer moving parts than folding chairs. This reduces the energy required to propel the chair by eliminating many flex points whereat the chair would flex as it moves. Welding the connections, rather than making them joints also reduces the overall weight of the chair. Even though they may be considered to be a rigid chair they typically feature instant-release rear wheels and backrests that fold down flat, allowing the user to dismantle the chair quickly for storage and transport in a car. 
     Many rigid models are made with lightweight materials such as aircraft aluminum and titanium. Rigid chair design can also have polymer shock absorbers, such as Frog Legs, which cushion the bumps over which the chair rolls. The shock absorbers may be added to the front wheels or to the rear wheels, or both. Rigid chairs also have the option for their rear wheels to have a camber. Wheels can have a camber, or tilt, which angles the tops of the wheels in toward the chair. This allows for better propulsion by the user which is desired by long-term users. Sport wheelchairs have large camber angles to improve stability. 
     Various optional accessories are available, such as anti-tip bars or wheels, safety belts, adjustable backrests, tilt and/or recline features, extra support for limbs or neck, mounts or carrying devices for crutches, walkers or oxygen tanks, drink holders, and clothing protectors. 
     Transport wheelchairs are usually light, folding chairs that are designed to be pushed by a caregiver to provide mobility for patients outside the home or common medical settings. 
     Variations in wheelchair construct include tilt wheelchairs that have seating surfaces which can be tilted to various angles. A standing wheelchair is one that supports the user in a nearly standing position. They can be used as both a wheelchair and a standing frame, allowing the user to sit or stand in the wheelchair as they wish. They often go from sitting to standing with a hydraulic pump or electric-powered assist. Bariatric wheelchairs are designed to support larger weights, since most standard chairs are designed to support no more than 250 lb. Pediatric wheelchairs are another available subset of wheelchairs. Hemi wheelchairs have lower seats which are designed for easy foot propulsion. 
     There are various mechanisms and caregiver techniques that are used to transition a person to/from a wheelchair. Each puts the person at the risk for injury. 
     What is needed in the art is a wheelchair system that reduces the risk of injury as the wheelchair is adapted for other uses. 
     SUMMARY OF THE INVENTION 
     The present invention provides a wheelchair system that converts to other transport configurations. 
     The invention in one form is directed to a convertible transport system including a seat portion, a back support portion, and a pivoting mechanism coupled to the seat portion and to the back support portion. The pivoting mechanism is configured to adjust and lock the back support portion relative to the seat portion, the pivoting mechanism having three operative states: a free pivoting state allowing the back support portion to pivot relative to the seat portion about an axis; a ratcheting state allowing the back support portion to only pivot toward the seat portion about the axis; and a locking state in which the pivoting mechanism is locked to thereby prevent a pivoting movement of the back support portion relative to the seat portion. 
     The invention in another form is directed to a convertible wheelchair system including a seat portion, a wheeled portion decouplable from the seat portion, a back support portion, and a pivoting mechanism coupled to the seat portion and to the back support portion. The pivoting mechanism is configured to adjust and lock the back support portion relative to the seat portion, the pivoting mechanism having three operative states: a free pivoting state allowing the back support portion to pivot relative to the seat portion about an axis; a ratcheting state allowing the back support portion to only pivot toward the seat portion about the axis; and a locking state in which the pivoting mechanism is locked to thereby prevent a pivoting movement of the back support portion relative to the seat portion. 
     An advantage of the present invention is that a patient can be repositioned from a sitting position in a chair to a reclining position in a bed, without being removed from the frame and cushions of the chair. 
     Another advantage is that a patient can be prepositioned on the mechanism in a bed and the mechanism can be lifted and reconfigured to the sitting position of a chair. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1A  illustrates an embodiment of a wheelchair of the present invention; 
         FIG. 1B  illustrates the wheelchair of  FIG. 1A  as the wheelchair takes one step in a transition for the transport of a patient arriving at a horizontal transport position; 
         FIG. 1C  illustrates the wheelchair of  FIG. 1A  as the wheelchair takes another step in the transition to a horizontal transport position; 
         FIG. 1D  illustrates the wheelchair of  FIG. 1A  as the wheelchair takes yet another step in the transition to a horizontal transport position; 
         FIG. 1E  illustrates the wheelchair of  FIG. 1A  as the wheelchair takes still yet another step in the transition to a horizontal transport position; 
         FIG. 2  is a closer look at a pivoting mechanism used on the wheelchair/transport system of  FIGS. 1A-1E ; 
         FIG. 3  is another view of the pivoting mechanism of  FIG. 2  used on the wheelchair/transport system of  FIGS. 1A-1E ; 
         FIG. 4  is yet another view of the pivoting mechanism of  FIGS. 2 and 3  used on the wheelchair/transport system of  FIGS. 1A-1E ; 
         FIG. 5  is still yet another view of the pivoting mechanism of  FIGS. 2-4  used on the wheelchair/transport system of  FIGS. 1A-1E ; 
         FIG. 6  is still yet another view of the pivoting mechanism of  FIGS. 2-5  used on the wheelchair/transport system of  FIGS. 1A-1E ; and 
         FIG. 7  illustrates three operating states of the pivoting mechanism of  FIGS. 2-6 . 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, and more particularly to  FIGS. 1A-1E and 2-7 , there is shown a Convertible transport system  10  having a wheelchair system  12  that includes a seat portion  14 , a back support portion  16 , and a wheeled portion  18 . Wheeled portion  18  has a chassis  20  with wheels  22  coupled thereto. 
     A pivoting mechanism  24  is coupled to seat portion  14  and to back support portion  16 . Pivoting mechanism  24  is configured to adjust and lock back support portion  16  relative to seat portion  14 . 
     The pivoting mechanism  24  has three operative states  100 , as illustrated in  FIG. 7 , those being a free pivoting state  102 , a ratcheting state  104 , and a cocking state  106 . The free pivoting state  102  allows back support portion  16  to pivot relative to seat portion  14  about an axis A 1  in either rotational direction, allowing back support portion  16  to pivot to any position, but preferably from a seated scenario to a horizontal laying flat scenario for a patient on seat portion  14 . The ratcheting state  104  allows the back support portion  16  to only fold or pivot toward the seat portion  14  about axis A 1 . The locking state  106  holds pivoting mechanism  24  in a locked position to thereby prevent a pivoting movement of the back support portion  16  relative to the seat portion  14 . 
     Wheeled portion  18  is couplable and decouplable to seat portion.  14 . A patient portion  26  of system  10  includes seat portion  14 , back support portion  16 , pivoting mechanism  24 , a foot support portion  28 , a connecting member  30 , and handles  32 . Patient portion  26  is detachable from wheeled portion  18  and can be lifted to a support  50 , which may be in the form of a cart  50  for the transporting of a patient, after patient portion  26  is coupled to support  50 . Support  50  has a framework  52  that has coupling devices to secure patient portion  26  thereto. Support  50  also has wheels  54  coupled to framework  52  for the ease of transporting patient portion  26 . Support  50  is couplable to seat portion  14 , but is not couplable to wheeled portion  18 . 
     Connecting member  30  is coupled to foot support portion  28  and to seat portion  14 . Connecting member  30  is pivotally coupled to foot support portion  28 , with connecting member  30  also being pivotally coupled to seat portion  14 . Connecting member  30  includes a mechanism  34  that couples an angular movement of foot portion  28  relative to connecting member  30  to an angular movement of connecting member  30  relative to seat portion  14 . Mechanism  34  of connecting member  30  causes a clockwise movement of connecting member  30  relative to seat portion  14  (about an axis A 2 ) to result in a counter-clockwise movement of foot support portion  28  (about an axis A 3 ). 
     The hinging mechanisms for axis A 1 , A 2  and A 3  can be a double Sprag roller clutch that can use a dampening biasing mechanism, for example in the form of a coil spring to provide a pre-loaded/dampening function. This alternative embodiment can have locking positions, for example, between and at 90 and 180 degrees of angular movement. The locking is bidirectional to provide a rigid transport system when the mechanism is locked. Each of the hinging mechanisms can have more than one loading spring to assist in the angular movement. It is also contemplated to have an active system driven pneumatically, hydraulically, or electrically to effect the movements described herein. It is also contemplated to have more than one pivoting mechanism per axis using a clutching and/or a ratcheting system to control the movement thereof. 
     At least one of handles  32  serves as a control device  32  that is controllingly coupled to pivoting mechanism  24 , with control device  32  being movable by an operator to select the operative state of pivoting mechanism  24 . Handles  32  are connected to back support portion  16 , and the coupling to pivoting mechanism  24  can be in the form of cables, pneumatic, hydraulic, electrical or other controllable elements. Control device  32  is connected at an end of the back support portion  16  that is opposite to the end to which the pivoting mechanism  24  is connected. Handle  32  can be twisted so that the operative state  102 ,  104  or  106  of the pivoting mechanism  24  is selected. When pivoting mechanism  24  has transitioned to a locking state  106  the ratcheting state  104  remains engaged, but is immobilized. 
     Looking now at  FIGS. 1A-1E  in sequence, the interaction of wheeled portion  18  and support  50  relative to patient portion  26  can be seen. As patient portion  26  transitions to the position shown in  FIG. 1B  connecting portion  30  has rotated in a clockwise direction about axis A 2 , and foot support portion  28  has pivoted counterclockwise about axis A 3 . In  FIG. 1C  patient portion  26  is detached from wheeled portion  18  by way of a lift mechanism, not shown, but known and used in medical and healthcare environments. In  FIG. 1D  patient portion  26  is moved atop support  50  and is secured thereto in  FIG. 1E . Also in  FIG. 1E , handle  32  has been twisted to place pivoting mechanism in state  102  from state  106  by way of state  104  so that back support portion  16  can be lowered to framework  52 . Note handle  32  also pivots for the ease of operator use. It is also contemplated that the pivoting of handle  32  may also control the angle of movement of back support portion  16  relative to seat portion  14  about axis A 1 . When back support portion  16  is resting upon framework  52 , pivoting mechanism can be placed in state  106 . It can be noted that the pivoting actions described can take place in differing amounts and differing sequences. 
     In a reverse order, when back support portion  16  is being raised, as shown in  FIG. 1E , handle  32  is twisted to place pivoting mechanism in state  104 , so that the raising of back support portion  16  takes place in a ratcheting mode. As back support portion  16  is moved pivoting mechanism  24  is not in locked state  106 , which would prevent a pivoting movement. 
     Now looking at  FIGS. 2-6  there are shown additional details of pivoting mechanism  24 . Pivoting mechanism  24  includes back arms  24 A, seat arms  24 B and housing  24 C. Back arms  24 A are coupled to back support portion  16  and seat arms  24 B are coupled to seat portion  14 . Within housing  24 C is ratcheting mechanism  24 D that has toothed sections  24 E and  24 F. A locking device  24 G has pins  24 I and pins  24 H extending therefrom. A sleeve  24 K is coupled to locking device  24 G. Toothed section  24 F is cupped on the inside so that locking device  24 G is contained therein. Pins  24 H are slidingly coupled to holes in toothed section  24 F and sleeve  24 K is coupled to locking device  24 G, so that the movement of sleeve  24 K on shaft  24 L when moved to the left causes pins  24 I to engage holes in toothed section  24 E, which places pivoting mechanism  24  into locked state  106  so that arms  24 A and  24 B are locked thereby preventing pivotal movement about axis A 1 . 
     A spring  24 J biases locking device  24 G toward locking state  106 . A spring  24 M biases toothed section  24 F toward toothed section  24 E. When handle  32  is positioned to place pivoting mechanism  24  in locking state  106  then device  24 G and section  24  are completely engaged to the leftmost positions. As handle  32  is twisted pivoting mechanism  24  transitions to ratcheting state  104  by the movement of sleeve  24 K, and hence locking device  24 G to the right causing pins  24 I to disengage from toothed section  24 E, while leaving spring  24 M causing sections  24 E and  24 F to remain engaged. Due to the angled tooth sequence of sections  24 E and  24 F arms  24 A and  24 B can ratchet about axis A 1 . When handle  32  is twisted further, causing pivoting mechanism  24  to transition to pivoting state  102  sleeve  24 K is moved further to the right causing locking device  24 G to bottom against an inside surface section  24 F causing section  24 F to disengage from section  24 E. 
     A reverse movement of handle  32  causes pivoting mechanism  24  to transition to ratcheting state  104  then to locked state  106 , as can be understood from the previous discussion. 
     While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.