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, which application is 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 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]    Corresponding reference characters indicate corresponding components throughout the several views of the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    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. 
         [0025]    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. 
         [0026]    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  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. 
         [0027]    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 . 
         [0028]    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 . 
         [0029]    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 . 
         [0030]    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 . 
         [0031]    The shock absorbing element  14  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  14  may be a metal spring, elastic material, or any structure both 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. 
         [0032]    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. 
         [0033]    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. 
         [0034]      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 . 
         [0035]      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. 
         [0036]      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    
         [0037]      FIG. 6A  shows a tilt angle A 5  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. 
         [0038]      FIG. 6B  shows the tilting of upper portion  18  as well as the tilting of the connecting rod  14  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 a vertical 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 connecting rod  14  is an angle A 6 . The total angle of angulation of the upper portion  18  is angle A 5  plus A 6 . 
         [0039]      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 . 
         [0040]      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 . 
         [0041]      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 . 
         [0042]    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.