Abstract:
An improved forearm or under arm crutch. The crutch features an extension which slides horizontally out of one of the handles and solidly connects to the tip of the other handle to form a stable seat where the user can rest. The crutch also features shock absorbing means. A shock absorbing means is at the foot of the crutch to cushion at the handle and another above the handle to independently cushion the forearm cuff or under arm pad. The crutch also features adjustable handles that articulate relative to the frame to comfortably accommodate users with various needs. The handle may also include a shock absorbing means integrated within the handle pad.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to mobility assistance devices, and more particularly, to ergonomically improved crutches. 
   2. Description of the Related Art 
   Several designs for crutches have been created in the past. None of them, however, include the novel ergonomic features claimed herein including a mechanism to readily transform the handles of the crutches into a rigid, two leg chair that the user can use as a resting seat, nor a shock absorbing mechanism above the crutch handles, nor a resilient articulated handle. 
   Applicant believes that one of the closest references corresponds to U.S. Pat. No. 6,397,868 issued to John E. Smith for a Seat Suspended Between Crutches. The Smith patent is essentially a fabric sling draped between two traditional under-arm crutches to form a seat. To practice the Smith invention the feet of the crutches must be positioned very close together to keep the seat spread making the seat inherently unstable and causing the user to be squeezed when his/her weight is applied to the seat. The Smith patent differs from the present invention, inter alia, because the present invention has a rigid frame forming the seat which permits the legs to be firmly placed further apart giving the seat much needed lateral stability while at the same time preventing the user from being squeezed in the chair when sitting. 
   Several other crutches have designs implementing shock absorbing mechanisms near the foot of the crutch. However, none of them have a shock absorbing mechanism superior to the handle. 
   Applicant believes that the closest reference including a shock absorbing feature corresponds to U.S. Pat. No. 2,888,022 issued to W. F. Fanning for a Shock Absorber for Orthopedic Crutches. The Fanning patent teaches a shock absorber in the foot of a crutch. It differs from the present invention because the present invention has a shock absorbing mechanism mounted independently above the load-bearing hand support member thus giving the forearm or under-arm support member its own independent shock absorbing mechanism. 
   Furthermore, none of the references known to applicant include a handle that articulates relative to the crutch assembly frame to more ergonomically interface with the user&#39;s hand and wrist. This feature translates into a more comfortable and ergonomic crutch. 
   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 the crutches user a seat integrated into the structure of the crutch that can be easily erected to allow the user to rest on a stable structure. 
   It is another object of the present invention to provide a more ergonomically designed forearm or underarm crutch increasing the comfort of the user by integrating an adjustable handle and, inter alia, shock absorbing features in the handle, the distal end of the crutch and the forearm cuff or underarm support. The foot of the crutch may have a shock absorbing mechanism. Another shock absorbing mechanism is mounted above the handle to independently cushion the forearm cuff or underarm support. The handle is adjustable to a range of angles to more closely align with the user&#39;s natural hand position and has integrated shock absorbing features. 
   It is still another object of this invention to provide features that increase the safety and/or comfort of the user. 
   It is yet another object of this invention to provide such a device 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  is an elevational view of the forearm crutch in one of the preferred embodiments. 
       FIG. 2  shows a partial view cross section of the shock absorber in the distal end of the stud assembly of the crutch at line  2  in  FIG. 1 . 
       FIG. 3  illustrates a partial elevational view of the handle, switches and light with a partial cross-section of the handle. 
       FIG. 4  is a partial elevational view of a pair of crutches that are joined through the handle connection to form a seat. 
       FIG. 5  is a partial cross-section view of the upper shock absorbing mechanism supporting the forearm cuff. 
       FIG. 6  is a partial elevation view of the handle area showing a mechanism to lock in an angular position of the handle. 
       FIG. 7  is a top elevation view of an alternate embodiment mechanism to lock in the handle at a predetermined angular position. 
       FIG. 8  is a perspective view of the handle with an alternate mechanism to lock in the angle of the handle. 
       FIG. 9  is a perspective view of a forearm crutch with support arm lowered. 
       FIG. 10  is a perspective view of two complimentary forearm crutches connected to each other to form a seat with their respective support arms. 
       FIG. 11  is a perspective view of a forearm crutch with support arm lowered. 
       FIG. 12  is a perspective view of the crutches demonstrating a seat formed between the crutches by their respective support arms. 
       FIG. 13  is a circuit diagram plan of the crutch. 
       FIG. 14  is an elevation partial view of a pair of crutches showing the crutches connected by bar seat members to form a seat. 
       FIG. 15  is a perspective view showing the locking mechanism in the handle that joins the handles to form a seat. 
       FIG. 16  is a cross section elevation of the upper shock absorbing assembly. 
       FIG. 17  is a perspective cross-section view of the crutches height adjusting mechanism. 
       FIG. 18  is a perspective cross-section view of the bracket of the upper shock absorbing mechanism. 
       FIG. 19  is an isometric view of the superior end of the supporting frame. 
   

   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 three major sectional components: a frame assembly  20 , a stud assembly  60  and an upper assembly  40 . These assemblies can be seen best generally in  FIG. 1 . 
   The frame assembly  20  is generally tubular. A light source  38  is mounted to frame assembly  20  and is controlled by switches  36  and  36 ′ to turn on and off. Light source  38  functions as a pathway light and alternately by actuating switch  36 ′, a flashing light beacon. Superior to the light source is adjustably and pivotally mounted handle assembly  22 . The handle is a load bearing member. To the top of the handle assembly  22  is affixed a resilient hand cushion  24 . Hand cushion  24  includes a handle shock absorbing assembly  25  comprised of coil springs  27 . In the handle shock absorbing assembly  25  the coil springs  27  can substituted for or augmented by an oil or pneumatic dampener or a leaf spring. Inside handle assembly  22  is a battery  32  accessed through a snap-on door  34 . A horn switch  28  is located under the handle assembly  22  that selectively activates horn  33  that is integrated in the supporting frame  21 . 
   In one of the preferred embodiments of the seat feature ( FIG. 4 , generally, and  FIG. 15 ), inside one handle of the pair is nested a slidably extendable and rotatable connecting bar  26  which slides partly out of the handle to firmly mate at the tip by rotating knurled grip  30  integrally connected to key  35  with a corresponding key slot  39  in receiving member  31  on the opposite crutch handle  28  to form a seat. Alternatively, connecting bar  31  may also be extendable so that the width of the seat to be increased further. 
   Another embodiment of the seat feature is depicted in  FIGS. 9 and 10 , generally. In this embodiment a hinged support arm  47  is hingedly mounted to frame assembly  20  by means of hinge pin  52 . On the first crutch of a pair, the tip of the hinged support arm  47  opposite the hinge pin  52 , is generally cylindrical and hollow and the corresponding mating tip  53  of the hinged support arm  47  of the second crutch of the pair has a smaller diameter sized to fit inside said tip of the first hinged support arm  47 . To form a seat the hinged support arms  47  of both crutches of a pair of crutches is raised and firmly mated with the tip of the corresponding hinged support arm  47  from the opposite crutch. 
   Yet another embodiment of the seat feature is depicted in  FIGS. 11 ,  12  and  14 . In this embodiment a longer hinged support arm  49  is hingedly mounted to frame assembly  20  by means of hinge pin  54 . To form a seat the longer hinged support arm  49  is raised and its distal end is secured to frame assembly  20  by locking pin  56  of the corresponding crutch. 
   As shown in  FIG. 6  the handle assembly  22  is connected to the supporting frame assembly  20  by axle pin  50 . The angle position of the handle assembly relative to the supporting frame is selected and fixed by a pin penetrated through one of the pre-determined angle selector holes  43  radially situated around the axle pin  50  and through a corresponding hole in the main frame. 
   Alternatively, the angle of the handle assembly  22  relative to the supporting frame  21  may be adjusted and fixed by a combination of radial grooves  46  and cam lock  45  as shown in  FIGS. 7 and 8 . In this embodiment said radial grooves  46  oriented on radii around an axle pin  44  on the handle integrate with corresponding grooves oriented on radii around the axle pin hole through the supporting frame. Said radial grooves  46  on the handle section and said corresponding radial grooves on the supporting frame firmly engage each other by means of the axle pin  44  and cam lock  45  that press the radial grooves  46  on the handle into said corresponding radial groves on the supporting frame effectively selecting the predetermined angle between the handle assembly  22  and frame assembly  20 . 
   As shown in  FIG. 1 , generally, and in detail in  FIG. 17  stud assembly  60  of the forearm crutch includes a stud section  62  that is telescopically received by the distal end of the supporting frame  21  and a gripping shoe assembly  64 . The stud section  62  has a two series of height adjustment holes  51  at predetermined positions on opposite sides and along the axis of said stud section  62 . The supporting frame  21  has a pair of holes  50  on opposite sides of the distal end. The stud section  62  is fixed at a selected height into the supporting frame  21  by a pin  90  secured into place by a hitch pin  92 . Alternatively, the height of the crutches may be selected by a spring plug located inside the stud section  62  and selected to fit into any of said series of height adjustment holes  51  and the corresponding hole on the distal end of the supporting frame  21  to accommodate variations in the height of different users. 
   The distal end of the lower stud section houses a shock absorbing assembly,  FIG. 2 , generally. A spring  64  (or hydraulic or other means not depicted) biases the distal end of the stud section  62  and the gripping shoe assembly  64  apart with predetermined force and elongated axially. The foot of the lower tubular member is capped by a ground contacting gripping shoe  66 . 
   An upper assembly  40  is shown in  FIG. 5  and its subassemblies are shown in more detail in  FIGS. 16 ,  18  and  19  and is comprised of a forearm cuff  42 , a spring  48  (or hydraulic or other means not depicted) and shock absorber body  55  with integrated mounting bracket  41 . The shock absorber body  55  is fixed onto the forearm cuff  42  by rivets  80 , screws, welds or other fixative means. The spring  48  is seated on spring seat  84  on one end and spring seat  86  on its opposite end. Said spring  48  biases the shock absorber body  55  (and therefore also the forearm cuff) apart from the supporting frame  21  with a predetermined resistance to provide a shock absorbing feature. 
   The upper shock absorbing mechanism is shown in more detail in  FIGS. 16 ,  18  and  19  where it is shown that the superior end of the supporting frame  21  has a ridge  94  that contacts a ledge  96  prevents the supporting frame  21  from separating from the shock absorber body  55 . The shock absorber body  55  and supporting frame  21  are prohibited from rotating axially relative to each other by means of a channel  88  vertically oriented in the superior end of the supporting frame  21  which mates with and is commensurate in depth with the length of an alignment pin  82  on the interior of the shock absorber body  55 . Optionally, there may be more than one pair of said channel  88  and corresponding alignment pin  82  situated around the superior end of the supporting frame  21  and corresponding surface of the shock absorber body  55 . 
   The forearm cuff  42  as shown generally in  FIG. 1  is shaped to ergonomically conform to the users forearm for maximum comfort. Another acceptable shape of a forearm cuff  42 ′ is shown generally in  FIGS. 9 through 12 . Likewise a traditional underarm support may be used instead of a forearm cuff and effectively employ and enjoy the same features as would a crutch using a forearm cuff. 
     FIG. 13  shows a circuit diagram of the electrical components. Element  32  is the battery. Switch  36  turns the light  38  on and off and switch  36 ′ in combination with a flasher means  36 ″ to provide a flashing light feature for light  38 . Horn switch  28  selectively activates horn  33 . 
   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.