Abstract:
An adaptive ambulatory support includes a shock absorbing and pivoting tip assembly attached to the staff of a walking aid, such as a cane, crutch or walker. The shock absorbing and pivoting tip assembly includes a shock absorber sandwiched between a lower portion and an upper portion. The shock absorber may be a bendable spring or elastic material. The tip assembly enables the shaft of the walking aid to dynamically pivot without the loss of adherence of the lower portion to the floor surface and simultaneous provides the adaptive shock absorbing capability in any angle during ambulation.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the priority of U.S. Provisional Patent Application Ser. No. 62/262,727 filed Dec. 3, 2015, and US patent application Serial No. U.S. Provisional patent application Ser. No. 15/368,333 filed Dec. 2, 2016, filed Dec. 3, 2015, which applications are incorporated in its entirety herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to walking aids and in particular to a walking cane having a shock absorbing tip. 
         [0003]    Walking aids such as walking sticks, crutches and walkers are well known and have been available in many varieties to accommodate a person&#39;s need of support and ambulation. Also there are a variety of modifications and accessories to these aids to ergonomically improve the comfort and safety. 
         [0004]    Most walking aids are provided with a rubber tip in an effort to provide stable engagement between the walking aids and the floor or other underlying support surface. In practice, however, it has been found that conventional rubber tips possess limitations which often result in severe injury to the user. For example, with most rubber tips the shaft of the walking aids needs to be held in substantially vertical alignment, so that the contact on the bottom of the tip is able to flatly engage the floor surface. Unfortunately, people frequently hold a walking aids at an outward angle from their bodies in an effort to steady themselves, so that the shaft extends at an angle to the floor rather than straight up and down. This causes the rubber tip to contact the floor at an angle, with only an edge of the tip engaging the floor surface. Consequently, when the person&#39;s weight bears on the cane at this angle, the tip tends to slide out, often causing the person to fall. Naturally, this problem is even more acute if the floor surface is slick or damp. 
         [0005]    There are also numerous shock absorbing accessories added to the walking aids. However, these shock absorbing devices are intended to merely vertically absorb the impact of the cane or other walking aids on the floor surface or other underlying support surface. 
         [0006]    While these walking aids fulfill their respective, particular objectives and requirements. They do not disclose an accessory for a walking aids which provides shockingly absorbing to reduce the impact as well as pivoting where the foot or tip of the accessory is maintained in a planar relationship with the supporting floor surface. In this regard where the foot or tip of the free end of the walking aid can be maintained in a parallel planar relationship with the floor supporting surface, no matter at what angle the walking aid is inclined relative to the supporting surface. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    The present invention addresses the above and other needs by providing an adaptive ambulatory support includes a shock absorbing and pivoting (or tilting) tip assembly attached to the staff of a walking aid, such as a cane, crutch or walker. The shock absorbing and pivoting tip assembly includes a shock absorber sandwiched between a lower portion and an upper portion. The shock absorber may be a bendable spring or elastic material. The tip assembly enables the shaft of the walking aids to dynamically pivot without the loss of adherence of the lower portion to the floor surface and simultaneous provides the adaptive shock absorbing capability in any angle during ambulation. 
         [0008]    In accordance with one aspect of the invention, there is provided an accessory for walking aids which provides shocking absorbing and reduced impact as well as pivoting where the foot or tip of the accessory is maintained in a planar relationship with the supporting ground surface. In this regard where the foot or tip of the free end of the walking aid can be maintained in a parallel planar relationship with the ground supporting surface, no matter at what angle the walking aid is inclined relative to the supporting surface. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0009]    The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein: 
           [0010]      FIG. 1A  is a side view of a cushioned walking stick tip according to the present invention. 
           [0011]      FIG. 1B  is a cross-sectional view of the cushioned walking stick tip according to the present invention taken along line  1 B- 1 B of  FIG. 1A . 
           [0012]      FIG. 2  shows a shock absorber according to the present invention. 
           [0013]      FIG. 3A  shows a single contact tip according to the present invention. 
           [0014]      FIG. 3B  shows a triple contact tip according to the present invention. 
           [0015]      FIG. 3C  shows a quadruple contact tip according to the present invention. 
           [0016]      FIGS. 4A and 4B  compare angulation of the tip using larger and smaller rod top stops according to the present invention. 
           [0017]      FIGS. 5A and 5B  compare angulation of the tip using longer and short connecting rods according to the present invention. 
           [0018]      FIGS. 6A and 6B  compare angulation of the upper portion of the tip when the connecting rod is vertical and when the connecting rod is tilted, according to the present invention. 
           [0019]      FIGS. 7A, 7B and 7C  compare a vertical position of the upper portion for different amounts for vertical force on the tip, according to the present invention. 
           [0020]      FIGS. 8A, 8B and 8C  compare a vertical position of the upper portion for different amounts for vertical force on the tip when the upper portion is tilted, according to the present invention. 
           [0021]      FIG. 9  shows a cushioned walking stick tip according to the present invention including a connecting bolt. 
           [0022]      FIG. 10  shows the connecting bolt according to the present invention. 
           [0023]      FIG. 11  shows a cushioned walking stick tip according to the present invention providing upper portion rotation. 
           [0024]      FIG. 12  shows an exploded view of the cushioned walking stick tip according to the present invention providing upper portion rotation. 
           [0025]      FIG. 13  shows a view of the cushioned walking stick tip according to the present invention providing upper portion rotation with upper and lower portions hidden to show other elements. 
           [0026]      FIG. 14  shows an exploded view of the cushioned walking stick tip according to the present invention providing upper portion rotation with upper and lower portions hidden to show other elements. 
           [0027]      FIG. 15A  shows a top view of a cup of the cushioned walking stick tip according to the present invention providing upper portion rotation. 
           [0028]      FIG. 15B  shows a bottom view of the cup of the cushioned walking stick tip according to the present invention providing upper portion rotation. 
           [0029]      FIG. 16  shows a cross-sectional view of the cup of the cushioned walking stick tip according to the present invention providing upper portion rotation taken along line  16 - 16  of  FIG. 15A . 
           [0030]      FIG. 17  shows a cross-sectional view of the upper portion according to the present invention. 
           [0031]      FIG. 18  shows a cross-sectional view of the upper portion according to the present invention where the bolt is tilted with respect to the lower porting and the upper portion is tilted with respect to the bolt. 
           [0032]      FIG. 19  shows a cross-sectional view of the upper portion according to the present invention where a solid walking stick has replaced a hollow shaft. 
           [0033]      FIG. 20A  shows a side view of a spacer according to the present invention for supporting the solid walking stick. 
           [0034]      FIG. 20B  shows a top view of the spacer according to the present invention for supporting the solid walking stick. 
           [0035]      FIG. 20C  shows a bottom view of the spacer according to the present invention for supporting the solid walking stick. 
           [0036]      FIG. 21  shows a cross-sectional view of the spacer according to the present invention for supporting the solid walking stick, taken along line  21 - 21  of  FIG. 20B . 
           [0037]      FIG. 22A  shows a front view of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0038]      FIG. 22B  shows a side view of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0039]      FIG. 22C  shows a top view of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0040]      FIG. 22D  shows a bottom view of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0041]      FIG. 23  shows a perspective view of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0042]      FIG. 24  shows a cross-sectional view of the three point embodiment of the cushioned walking stick tip according to the present invention taken along line  24 - 24  of  FIG. 22A . 
           [0043]      FIG. 25A  shows a bottom/side perspective view of one of three adapters of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0044]      FIG. 25B  shows a top/side perspective view of one of the three adapters of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0045]      FIG. 26  shows a side view of one of the three adapters of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0046]      FIG. 27  shows a cross-sectional view of one of the three adapters of the three point embodiment of the cushioned walking stick tip according to the present invention taken along line  27 - 27  of  FIG. 26 . 
           [0047]      FIG. 28A  shows a top perceptive view of a center fitting of the three point embodiment of the cushioned walking stick tip according to the present invention. 
           [0048]      FIG. 28B  shows a bottom perceptive view of a center fitting of the three point embodiment of the cushioned walking stick tip according to the present invention. 
       
    
    
       [0049]    Corresponding reference characters indicate corresponding components throughout the several views of the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0050]    The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims. 
         [0051]    Where the terms “about” or “generally” are associated with an element of the invention, it is intended to describe a feature&#39;s appearance to the human eye or human perception, and not a precise measurement. 
         [0052]    A side view of a cushioned walking stick tip  10  according to the present invention is shown residing on a generally horizontal surface  11  in  FIG. 1A  and a cross-sectional view of the cushioned walking stick tip  10  along line  1 B- 1 B of  FIG. 1A  is shown in  FIG. 1B . The cushioned walking stick tip  10  is an economical direct replacement for the simple rubber tip commonly used in walking aids, providing an easy and economical solution to ambulatory support and traction for a walking aid such as a cane, crutches and walkers. The cushioned walking stick tip  10  includes four major components, an upper portion  18  including a shaft passage  18   a  receiving a shaft  12  of the walking aid, a lower portion  26  having a bottom surface  26   a  which maintains a parallel planar relationship with the ground, a shock absorbing element  24  between the upper portion  18  and the lower portion  26 , and a pivoting connecting rod  14  embedded in the lower portion  26  and connecting the upper portion  18  to the lower portion  26 . The upper portion  18  is preferably connectable to the shaft  12  without tools or an adaptor. 
         [0053]    The tip assembly  10  provides an upper pivot  20  in the upper portion  18  and a lower pivot  28  in the lower portion  26 . The attitude of the lower pivot  28  is generally fixed with respect to the generally horizontal surface  11  and is limited to movement resulting from deformation of the lower portion  28 . The lower pivot  28  allows the angulation of the connecting rod  14  when a rod top stop  16  reaches the inner wall of the shaft  12 . The force from the partial body weight and the angulation is passed from the shaft  12  to the rod top stop  16 . The force applied to the rod top stop  16  causes the connecting rod  14  to pivot around the lower pivot  28 . 
         [0054]    The upper portion  18  and upper pivot  20  may both pivot and depress vertically under a load. The position of the upper pivot  20  is the location where the partial body weight bears on the shaft  12  and the compression force of the shock absorber  24  reach a balance. The partial body weight on the shaft  12  is different for each ambulation because of angulation, therefore the tip assembly  10  adaptively seeks the dynamically moving pivot until the balance of the forces is reached. The upper pivot  20  allows the angulation of the shaft  12  relative to both the upper portion  18  and the lower portion  26 . 
         [0055]    The location of the upper pivot  20  is established by an upper centering piece  22  fixed to the upper portion  18  and the lower pivot  28  may be established by a lower centering piece  30  fixed to the lower portion  26 . The upper and lower centering pieces  22  and  30  are preferably disks embedded in the upper portion  18  and lower portion  26  respectively. The connecting rod  14  includes a rod top stop  16  at the top of the connecting rod  14  limiting pivoting about the upper pivot  20  by the connecting rod  14  by contact of the rod top stop  16  with the interior of the shaft  12 , and a rod center stop  17  retaining the upper portion  18  on the connecting rod  14 . 
         [0056]    An upper pivot point  20  allows pivotal motion of the upper portion  18  of the walking aid  10  relative to the connecting rod  14  and the lower portion  26  while the rod top stop  16  is not touching the inner wall of the shaft  12 . The connecting rod  14  is generally perpendicular to the lower portion  26  and the surface  11  when relaxed. The lower pivot  28  also allows the angulation of the upper portion  18  and the shaft  12  relative to the lower portion  26  and the surface  11  when the rod top stop  16  touches the inner wall of the shaft  12 . Sufficient force on rod top stop  16  due the angulation of the shaft  12  may cause the connecting rod to  14  pivot at the lower pivot point  28 . 
         [0057]    The shock absorbing element  24  resides between the upper portion  18  and the lower portion  26  and is retained in place by the connecting rod  14 . The shock absorbing element  24  may be a metal spring, elastic material, or any structure which is both compressible and flexible. An example of a suitable shock absorber  24  is a wave spring  24   a  shown in  FIG. 2 . The spring  24   a  is interchangeable to allow the user to select a different spring  24   a  with different spring constant to provide a desired stability or comfort level. 
         [0058]    The lower portion  26  preferably maintains in a parallel planar relationship with the surface  11 .  FIGS. 3A, 3B and 3C  show examples of single contact  26   a  or multiple contact such three toe tri-pod  26   b  or four toe quad-pod contact  26   c . The multiple prong lower tips  26   b  and  26   c  enable the support to be self-standing. 
         [0059]    The connecting rod  14  is ridged and resides substantially perpendicular to the lower portion  26  and surface  11  for small angular deflections of the shaft  12 , and supports dynamic pivoting of the upper portion  18  about the lower pivot  28 . The connecting rod  14  is also a mechanical guide which guides the upper portion  18  to move up and down along the connecting rod  14  during ambulation. The connecting rod  14  is a safety device to prevent the upper portion  18  and shaft  12  from over tilting, causing contact of the rod top stop  16  with the shaft  12 , which may cause a user to fall. 
         [0060]      FIG. 4A  shows the connecting rod  14  with a larger rod top stop  16   a . The larger rod top stop  16   a  functions as mechanical stop that resists the upper portion  18  and shaft  12  from further tilting thus limits the angle of angulation during ambulation to a first angle A 1 . 
         [0061]      FIG. 4B  shows the connecting rod  14  with a smaller rod top stop  16   b . The rod top stop  16   b  creates clearance to allow the upper portion  16  and the shaft  12  to tilt further to an angle A 2  compared to the rod with the larger end stop  16   a . The end stops  16   a  and  16   b  are preferably interchangeable to allow the user to use different sizes of end stop which fits them better to provide better stability and comfort. 
         [0062]      FIGS. 5A and 5B  show a connecting rod  14  having an adjustable length. The length of the connecting rod  14  inside the shaft  12  can be extended by attaching a removable rod section  14   b  to a base rod  14   a . The length can be reduced by detaching the removable rod  14   b . By adjusting the length of the connecting rod  14  the maximum of angle of upper portion  18  with respect to the connecting rod  14  can be adjusted. A smaller angle A 3  is shown in  FIG. 5A  when the removable rod section  14   b  is attached to the base rod  14   a , and a greater angle A 4  is shown in  FIG. 5B  when the removable rod section  14   b  is not attached to the base rod  14   a    
         [0063]      FIG. 6A  shows a tilt angle A 5  between a centerline CL 1  of the connecting rod  14  (aligned with vertical V) and a centerline CL 2  of the upper portion  18  when the rod top stop  16  reaches the inner wall of shaft  12  during the ambulation of the user. The connecting rod  14  maintains a substantially vertical position and the lower portion  26  maintains a planar relationship to the surface  11  to maintain the stability and safety. 
         [0064]      FIG. 6B  shows the tilting A 5  of the centerline CL 2  of upper portion  18  with respect to the connecting rod  14 , as well as the tilting A 6  of the centerline CL 1  of the connecting rod  14  with respect to the vertical V, when force from the inner wall of the shaft  12  is applied against the rod top stop  14 . The connecting rod  14  moves away from the vertical V position but the lower portion  28  maintains a planar relationship to the surface  11  to maintain the stability and safety. The tilting angle of the centerline CL 1  of the connecting rod  14  with respect to the vertical V is an angle A 6 . The total angle of angulation of the upper portion  18  is angle A 5  plus A 6 . The total angle of angulation of the upper portion  18  is angle A 5  plus A 6 . 
         [0065]      FIGS. 7A, 7B and 7C  depict a shock absorbing capability when only a vertical force is applied downward on the cushioned walking stick tip  10 . The upper portion  18  moves downward along the connecting rod  14 . The distance the upper portion  18  travels downward depends on the downward force and the resistance of the shock absorber  24 . The lower portion  28  maintains planar relationship with the surface  11 . 
         [0066]      FIGS. 8A, 8B and 8C  depict the upper pivot  20  moving progressively along the connecting rod  14  during the ambulation. The upper portion  18  is tilted at a fixed angulation in  FIGS. 8A, 8B and 8C  for illustration purpose. The actual tilting angle varies depending on the load from partial body weight on the walking aid. The distance the upper portion  18  travels downward depends on the vertical component FY of the force F the shaft  12  exerts on the upper portion  18 , and the resistance of the shock absorber  24 . The lower portion  28  maintains planar relationship with the surface  11 . 
         [0067]      FIG. 9  shows a cushioned walking stick tip  10   a  including a connecting bolt  32  and  FIG. 10  shows the connecting bolt  32  and nut  34 . The connecting bolt  32  connects the upper portion  18  to the lower portion  26  sandwiching the shock absorber  24 . The nut  34  may be a lock nut, or may be a nut tightened against an unthreaded portion  32   a  of the connecting bolt  32 . 
         [0068]    A cushioned walking stick tip  10   b  providing upper portion  18   a  rotation is shown in  FIG. 11 , an exploded view of the cushioned walking stick tip  10   b  is shown in  FIG. 12 , a view of the cushioned walking stick tip  10   b  with upper portion  18   a  and lower portion  26   a  hidden to show other elements is shown in  FIG. 13 , and an exploded view of the cushioned walking stick tip  10   b  providing upper portion rotation with upper portion  18   a  and lower portion  26   a  hidden to show other elements is shown in  FIG. 14 . The cushioned walking stick tip  10   b  includes a bolt  32  connecting the upper portion  18   a  to the lower portion  26   a . A nut  34  retains the upper portion  18   a  on the bolt  32 . A first washer  40  resides under the nut  34  in a recess in a first cup  42 . A second washer  44  embedded in the upper portion  18   a  resides under the first cup  42 . A second cup  46  (or upper pivot) is embedded in the upper portion  18   a  and includes a cylindrical portion  52  (see  FIG. 16 ) reaching through a passage  56  (see  FIG. 17 ) of the upper portion  18   a . A third washer  48  resides between the second cup  46  and the shock absorber  24 . The second cup  46  and washer  48  are made from self lubricating plastic to facilitate rotation of the top portion  18   a  with respect to the bottom portion  26   a . The bottom portion  26   a  includes a recess  27  to receive and position the bottom of the shock absorber  24 . 
         [0069]    A top view of the second cup  46  is shown in  FIG. 15A , a bottom view of the cup  46  is shown in  FIG. 15B , and a cross-sectional view of the cup  46  taken along line  16 - 16  of  FIG. 15A  is shown in  FIG. 16 . The cylindrical portion  52  of the cup  46  passes through the bottom of the upper portion  18   a  and the washer  44 , and rests against the bottom of the cup  46 , thus preventing deformation of the bottom of the upper portion  18   a . The cup  46  and the washer  48  are made from self-lubricating material, preferably self lubricating plastic, to allow the upper portion  18   a  to rotate with respect to the lower portion, 
         [0070]    A cross-sectional view of the upper portion  18   a  is shown in  FIG. 17 . The portion  18   a  includes a passage  56  provided for the cylindrical portion  52  of the second cup  46 , and a bottom recess  58  to receive and position the top of the shock absorber  24 . 
         [0071]      FIG. 18  shows the tilting A 5  of the centerline CL 2  of upper portion  18   a  with respect to the bolt  32 , as well as the tilting A 6  of the centerline CL 1  of the bolt  32 , with respect to the vertical V, when force from the inner wall of the shaft  12  is applied against the nut  34 . The bolt  32  moves away from the vertical V position but the lower portion  28  maintains a planar relationship to the surface  11  to maintain the stability and safety. The tilting angle of the centerline CL 1  of the bolt  32  with respect to the vertical V is an angle A 6 . The total angle of angulation of the upper portion  18  is angle A 5  plus A 6 . The total angle of angulation of the upper portion  18  is angle A 5  plus A 6 . 
         [0072]    A cross-sectional view of the upper portion where a solid walking stick  13  has replaced the hollow shaft  23 , and a s spacer  60  supports the solid walking stick  13 . A side view of the spacer  60  is shown in  FIG. 20A , a top view of the spacer  60  is shown in  FIG. 20B , a bottom view of the spacer  60  is shown in  FIG. 20C , and a cross-sectional view of the spacer  60  taken along line  21 - 21  of  FIG. 20B  is shown in  FIG. 21 . The spacer  60  resides over the nut  34  and bolt  32  to prevent the bottom end of the solid walking stick  13  from interfering with movement of the upper portion with respect to the bolt. 
         [0073]    A front view of the three point embodiment  70  of the cushioned walking stick tip according to the present invention is shown in  FIG. 22A , a side view of the three point embodiment  70  is shown in  FIG. 22B , a top view of the three point embodiment  70  is shown in  FIG. 22C , and a bottom view of the three point embodiment  70  is shown in  FIG. 22D . The three point embodiment  70  includes a center fitting  80  connected to three of the cushioned walking stick tips  10   a  by adapters  72 . The shaft  12  (see  FIG. 1A, 1B ) is attached to the fitting  80 . The three point embodiment  70  provides additional stability when using the walking aid. The cushioned walking stick tips  10   a  are spaced about 120 degrees apart and tilted out a tilt T of about 10 degrees. 
         [0074]    A perspective view of the three point embodiment  70  is shown in  FIG. 23  and a cross-sectional view of the three point embodiment  70 , taken along line  24 - 24  of  FIG. 22A , is shown in  FIG. 24 . As seen in  FIG. 24 , the cushioned walking stick tips  10   a  provide impact reduction when using the three point embodiment  70 . 
         [0075]    A bottom/side perspective view of one of three adapters  72  of the three point embodiment  70  is shown in  FIG. 25A , a top/side perspective view of one of the three adapters  72  is shown in  FIG. 25B , a side view of one of the three adapters  72  is shown in  FIG. 26 , and a cross-sectional view of one of the three adapters, taken along line  27 - 27  of  FIG. 26 , is shown in  FIG. 27 . Each of the adapters  72  includes a cylindrical portion insertable into the cushioned walking stick tips  10   a  and a threaded portion  76  for attachment to the center fitting  80 . The attachment to the center fitting  80  may be threaded with either the adapters  72  having female threads and the center fitting  80  having male threads, or the adapters  72  having male threads and the center fitting  80  having female threads. Further, those skilled in the art will recognize various ways of attaching the adapter to the cushioned walking stick tips  10   a  and to the center fitting  80 , and that the center fitting  80  may be directly attached to the cushioned walking stick tips  10   a  without adapters, and all of these variations are intended to come within the scope of the present invention. The adapters  72  may include a knurled surface to facilitate attachment to the center fitting  80 . 
         [0076]    A top perceptive view of the center fitting  80  of the three point embodiment  70  is shown in  FIG. 28 a    and a bottom perceptive view of a center fitting  80  is shown in  FIG. 28B . The center fitting  80  includes the male threads  82  for attaching the adapters  72 , and male threads  84  for attaching the shaft  12 . Those skilled in the art will recognize various ways of attaching the adapter  72  to the center fitting  80  and the center fitting to the shaft  12 , and that the center fitting  80  may be part of the shaft  12 , and all of these variations are intended to come within the scope of the present invention. 
         [0077]    While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.