Patent Publication Number: US-2009235966-A1

Title: Ergonomic crutches

Description:
OTHER RELATED APPLICATIONS 
     The present application is a continuation-in-part of pending U.S. patent application Ser. No. 11/531,953, for Ergonomic Crutches filed on Sep. 14, 2006, currently allowed which is hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to ergonomic crutches, and more particularly, to mobility assistance devices that are ergonomically designed and transmit a user&#39;s load with minimal abrupt changes. 
     2. Description of the Related Art 
     Several designs for crutches have been designed in the past. None of them, however, includes the ergonomic features claimed in the present application, specifically those that minimize abrupt transfers of a user&#39;s load through his/her affected body members (hand, arm, forearm) to the crutch assembly. Additionally, these features also provide lateral stability and at rest comfort. 
     Many crutch users complain about the difficulties, and some trauma, experienced with their crutches. These devices are intended to shift the user&#39;s weight load from their legs and feet to other parts of their bodies that usually do not bear these loads. As a user walks, moves, or even stays stationary, the transfer of this weight load is relatively abrupt. Thus, there is a need for crutches that slowly transfer the weight load of the user&#39;s body to minimize the abruptness of these transfers. 
     The parent application provides for features that permit a user to sit down using cooperatively designed handles and discloses other features that have been improved in the present application. One of these features relate to the articulated mechanism used for the handles that are capable of withstanding considerable larger loads than in the parent application, now allowed. The improvements claimed in the present application optimize the use of the ergonometrically compatible crutches while minimizing discomfort. 
     Other patents describing the closest subject matter provide for a number of more or less complicated features that fail to solve the problem in an efficient and economical way. None of these patents suggest the novel features of the present invention. 
     SUMMARY OF THE INVENTION 
     It is one of the main objects of the present invention to provide an ergonomically designed crutch that minimizes abrupt transfers of weight load, through the user/crutch combination. 
     It is another object of this invention to provide such a crutch that can be adjusted to a user&#39;s physical needs and its features selectively enabled. 
     It is still another object of this invention to provide a crutch with lateral stability. 
     It is still another object of the present invention to provide a lightweight crutch. 
     It is yet another object of this invention to provide such a crutch that is inexpensive to manufacture and maintain while retaining its effectiveness. 
     Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       With the above and other related objects in view, the invention consists in the details of construction and combination of parts as will be more fully understood from the following description, when read in conjunction with the accompanying drawings in which: 
         FIG. 1  represents an isometric view of the present invention. 
         FIG. 2  represents an isometric view of the crutch shown in  FIG. 1  from a different angle. 
         FIG. 3  illustrates an elevational view of the upper portion of the crutch shown in the previous figures with a partial cross-section of the angular adjustment mechanism for the handle assembly. 
         FIG. 3A  is an enlarged isometric view of one half of the handle assembly housing. 
         FIG. 4  is an enlarged cross-sectional view of the adjustable handle assembly. 
         FIG. 4A  schematically illustrates the handle shock absorber assembly including the backbone leaf spring mechanism and resilient cushion member with an arrow showing the application of the load. 
         FIG. 4B  is an enlarged partial cross-sectional view of the locking mechanism. 
         FIG. 5  is an enlarged side view of the cuff member with pivotally mounted armband. 
         FIG. 6  is an enlarged isometric view of one of the preferred embodiments of the crutch shoe. 
         FIG. 7  is an elevational cross-section of the crutch&#39;s lowermost portion of the leg with shoe, showing the internal shock absorbing assembly. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, where the present invention is generally referred to with numeral  10 , it can be observed that it basically includes extendable leg assembly  20 , handle assembly  40 , extendable cuff assembly  60 , knee rest assembly  80 , and shoe assembly  100 . 
     As shown in  FIGS. 1 and 2 , telescopic or extendable leg assembly  20 , having ends  21  and  21 ′, includes tubular member  22  coaxially and telescopically housing tubular member  24  therein. Shock absorbing assembly  26 , as best seen in  FIG. 7 , is housed within shock sleeve  28  and inserted within member  24 . End  23  of member  24  is adjustably mounted within end  22 ′ of member  22 . Shoe assembly  100  is mounted to end  23 ′ of member  24 . Handle assembly  40  is mounted at end  21  of assembly  20 . 
     As seen in  FIGS. 3 and 4 , handle assembly  40  includes housing  42  with a central portion  41  and side portions  41 ′ and  41 ″. Tubular member  43  extends from side  41 ′ and inclined tubular member  45  extends from opposite side  41 ″. Opening  47  in housing  42  is opposite to central portion  41  and permits shank  44 ″ to move angularly between two extreme positions about a pivot point  44 ′ centrally located on teethed wheel section  44  mounted to the end of shank  44 ″. Wheel section  44  includes central through opening  44 ′ through which headed pin  25  passes and is held in place with rivets or nuts, as shown in  FIGS. 1 and 2 . 
     As best seen in  FIG. 3A , bushing  43 ′ is designed to receive therethrough the shank of head pin  25  which also goes through opening  144 ′ of wheel section  144 . 
     Locking member  46  includes a block member  46 ′ at one end with teeth  46 ″ that cooperatively engage with mating teeth  44 ″ of wheel section  44  to keep the latter in place and thus handle member  49 , as best seen in  FIG. 4 . Spring  48 ′ urges block member  46 ′ against mating teeth  44 ″. Another embodiment for locking member  46  is shown as  146  in  FIG. 4B , which includes a knurled knob  146 , in this embodiment. A threaded shank  146 ′ passes through opening  143  in cover  148  which in turn is mounted to housing  142 . Shank  146 ′ is inserted inside block  145  that includes central threaded opening  145 ′. Retainer collar  149  keeps shank  146 ′ in place. Central threaded opening  145 ′ cooperatively mates with threaded shank  146 ′. Upon rotation of shank  146 ′, block  145  advances between two extreme positions inside tubular member  142 ′ of housing  142 . Block  145  has, at its end, a teethed arch member  145 ″ that mates with wheel section  144 . In one of the extreme positions that block  145  travels to, arch member  145 ″ is disengaged from wheel section  144  permitting a user to adjust the angular position of handle assembly  40  to the user&#39;s preferences, at the other extreme position, teethed arched member  145 ″ matingly and lockingly engages with the teeth of wheel section  144 . For better performances, wheel section  144  and teethed arched member  145 ″ are made out of a strong metal, such as steel or equivalent. 
     Leaf spring  48  is mounted relatively close to the upper side of member  49 . Spring  48  is positioned to permit a predetermined degree of deflection upon the application of force through cushion  150  which is made out of a resilient material. Handle member  49  and leaf spring  48  are covered with high performance gel grip with an overall effect to dampen sudden load transmissions through a user&#39;s palms. This minimizes trauma to a user&#39;s hands and wrist by reducing abrupt changes of the bearing load. 
     Light assembly  50  is cooperatively mounted below handle assembly  40  to direct the light from lighting element  51  (LED or light bulb or equivalent) housed within light assembly compartment  52 . Light switch  53  is conveniently mounted at the end of handle member  49 , as best seen in  FIG. 2 . A sound generating assembly  55  is housed within handle member  49 , at its distal end, as best seen in  FIG. 2 . 
     Cuff assembly  60 , as shown in  FIG. 5 , includes cuff member  61  that cooperatively and ergonomically receives a user&#39;s forearm. An extendable rigid guide member  63  supports cuff member  61  to permit a user to change its relative position. Cuffs  61  and  62  provide lateral support to stabilize the use of crutch  10 . Strap loop  64  is pivotally mounted to either guide member  63  or cuffs  61  and  62  adjacent to end  63 ″ and it has cooperative dimensions to permit a user to pass his/her forearm through. Loop  64  permits a user to free up his/her hands while still keeping crutch  10  within reach hanging from his/her forearm. End  63 ′ of guide member  63  is mounted within member  45 . 
     Knee rest assembly  80  is pivotally mounted to tubular member  22  at a predetermined desired distance from the either end. Assembly  80  includes platform member  82  that is pivotally mounted, at one end, to member  22 . The other end provides sufficient resting area for a user to lean against with his knee. Reinforcement member  84  runs along the underside of platform member  82 . 
     Shoe assembly  100 , as shown in  FIGS. 6 and 7 , is mounted to the distal end of tubular member  24  through shock absorbing assembly  26 . In one of the preferred embodiments, shoe assembly  100  includes bottom wall  102  that permits an engagement with the supporting surface on the crutch approach, while on it and as exiting the engagement surface. Bottom wall  102  has arched forward and rear ends  103  and  104  with a substantially flat portion  105  in between. Extending laterally from flat portion  105  are lateral flanges  106  and  107  that provide lateral stability to shoe assembly  100 . From the upperside of portion  105  extends cylindrical member  109  a sufficient distance to receive the distal end of tubular member  24 . 
     The foregoing description conveys the best understanding of the objectives and advantages of the present invention. Different embodiments may be made of the inventive concept of this invention. It is to be understood that all matter disclosed herein is to be interpreted merely as illustrative, and not in a limiting sense.