Abstract:
A stepper scooter provides step pads that are connected to a laterally arranged rocker bar assembly. Vertical movement of the step pads causes the rocker bar assembly to reciprocally pivot which translates drive chains which cause rotation of the drive wheel or wheels. The rocker bar assembly comprises two four bar linkages between a center fork and each step pad. An alternate embodiment uses the rocker bar to reciprocally rotate a gear axle which drives a bevel gear arrangement to rotate the drive wheel or wheels via one-way bearings. Another embodiment incorporates a chain and sprocket drive between the bevel gear arrangement and the drive wheel or wheels, wherein the one-way bearings are replaced with a one-way sprocket drive.

Description:
[0001]    This application claims the benefit of U.S. Provisional Application 62/005,641, filed May 30, 2014. 
     
    
     BACKGROUND 
       [0002]    Human powered, step-propelled scooters are known. These scooters generally use an up and down motion from a human&#39;s legs to propel the scooter, such as described in U.S. Pat. No. 5,368,321; U.S. Pat. No. 6,334,838; U.S. Pat. No. 6,402,173; U.S. Pat. No. 6,520,525; U.S. Pat. No. 6,648,355; U.S. Pat. No. 6,716,141; U.S. Pat. No. 6,764,088; U.S. Pat. No. 8,579,769; U.S. Pat. No. 7,581,742; US patent application 2006/0119052; US patent application 2010/0225085; US patent application 2004/0036249; US patent application 2010/0001487; and US patent application 2010/00320716. These documents are herein incorporated by reference to the extent not inconsistent with the present disclosure. 
         [0003]    The disclosed scooters use a pivoting motion of the pedals to convert the general up and down motion of the user&#39;s legs to rotary power at the rear wheel or wheels of the scooter. 
         [0004]    The present inventor has recognized that prior art step-propelled scooters are driven by inclined pedals which tend to elongate the scooter and may require an uncomfortable leg motion or posture by the user during operation. 
       SUMMARY 
       [0005]    Exemplary embodiments of the invention provide methods for propelling a stepper machine and improve existing methods for propelling human powered vehicles, such as scooters. Exemplary embodiments of the invention operate in a more comfortable vertical motion than the traditional angle of operation required by other stepping devices. 
         [0006]    An exemplary embodiment of the invention provides step pads that are connected to a laterally arranged rocker bar assembly. Vertical movement of the step pads causes the rocker bar assembly to reciprocally pivot which translates drive chains which cause rotation of the drive wheel or wheels. 
         [0007]    Advantageously, the rocker bar assembly comprises two rocker bars that are operatively connected in parallel to a center fork and at each end to step pad connectors for the step pads, forming four bar linkages between the center fork and each step pad. This creates a substantially vertical up and down movement of the stepper pads and a more comfortable movement for the user. 
         [0008]    An alternate embodiment uses the rocker bar to reciprocally rotate a gear axle which drives a bevel gear arrangement to rotate the drive wheel or wheels via one-way bearings. Another embodiment incorporates a chain and sprocket drive between the bevel gear arrangement and the drive wheel or wheels, wherein the one-way bearings are replaced with a one-way sprocket drive. 
         [0009]    Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a perspective view of an embodiment of a scooter according to the invention; 
           [0011]      FIG. 2  is a detail exploded view of the scooter of  FIG. 1 , with some parts removed for clarity; 
           [0012]      FIG. 3  is a sectional view taken along line  3 - 3  in  FIG. 1 ; 
           [0013]      FIG. 3A  is a sectional view of an alternate arrangement taken generally along line  3 - 3  of  FIG. 1 ; 
           [0014]      FIG. 4  is a sectional view taken along line  4 - 4  in  FIG. 3 ; 
           [0015]      FIG. 4A  is a sectional view of an alternate arrangement taken generally along line  4 - 4  in  FIG. 3A ; 
           [0016]      FIG. 5  is a sectional view taken along line  5 - 5  in  FIG. 3 ; 
           [0017]      FIG. 6  is a rear view of the scooter of  FIG. 1 , illustrating the movement of the rocker bars; 
           [0018]      FIG. 7  is a perspective view of an alternate embodiment a scooter according to the invention; 
           [0019]      FIG. 8  is a sectional view taken along line  8 - 8  in  FIG. 7 ; 
           [0020]      FIG. 9  is a rear view of scooter of  FIG. 7 , illustrating the movement of the rocker bars, large bevel gear, and bevel gear axle; 
           [0021]      FIG. 10  is a perspective view of a further alternate embodiment a scooter according to the invention; 
           [0022]      FIG. 11  is a sectional view taken along line  11 - 11  in  FIG. 10 ; 
           [0023]      FIG. 12  is a perspective view of an accessory for the scooters of  FIGS. 1-11 ; 
           [0024]      FIG. 13  is an end view of the accessory of  FIG. 12  taken along line  13 - 13  of  FIG. 12 ; and 
           [0025]      FIG. 14  is a side view of the accessory of  FIG. 12  taken along line  14 - 14  of  FIG. 12 . 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    While this invention is susceptible of embodiment in many different forms, there are shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated. 
         [0027]      FIG. 1  illustrates a step-propelled scooter  10 . The scooter includes step pads  12  mounted on rocker bars  14  via step pad connectors  16  and outer rocker pivot rods  18 . A center rocker fork  20  mounts the rocker bars  14  via center rocker pivot rods  22 . A base plate  24  includes a base plate fork slot  25  for passage of the fork  20  and base plate chain slots  26  for passage of left and right drive chains  62  (described below). A center frame member  84  supports the base plate  24  and is connected to a front angled frame member  73 . 
         [0028]    As shown in  FIGS. 2-6 , a rear axle  28  mounts rear wheels  30 . A sprocket tube  32  surrounds the rear axle rotatably carries sprockets  34 . The sprockets  34  have one direction, freewheeling hubs within the sprocket tube to allow the sprockets  34  to drive the axle  28  in the forward direction and to free wheel in the reverse direction and also to freewheel when coasting, i.e., when the user is not stepping but wants the scooter to continue coasting. One direction, freewheeling hubs are well known for bicycles. Examples of bicycle hubs are disclosed in U.S. Pat. Nos. 4,593,799; 3,010,553; 3,709,341; 8,556,055, herein incorporated by reference to the extent not inconsistent with the present disclosure. The sprocket tube  32  is fixed to the center frame member  84 . Center guide wheels  36  are carried on center wheel axles  38  via center guide wheel holes  40  and mounted to the step pad connectors  16 . Rear guide wheels  42  are carried on rear guide wheel axles  44  via rear guide wheel holes  46 . Horizontal guide wheels  48  having horizontal guide wheel holes  50  are mounted on horizontal wheel rods  52 , carried on horizontal wheel posts  54  which extend from the rods  52 . 
         [0029]    Chain posts  56  receive chain bolts  58  which secure ends of the chains  62  to the posts  56  by chain bolt nuts  60 . A cord  64  connects together opposite ends of the chains  62 . 
         [0030]    A front wheel  66  supports a front of the scooter  10 . The front wheel  66  supports a front fork  67  connected to a steering tube  69  which is rotatable within a head tube  71 . The steering tube is connected to handlebars  68 . A brake  70  is carried by the handlebars  68  and acts on one or more of the wheels in conventional fashion, i.e., urging calipers to pinch a brake disc (not shown). The head tube  71  is mounted to the angled frame member  73 . The angled frame member  73  is pivotally attached to the frame member  84  and selectively locked in upright condition as shown in  FIG. 1 . The frame member  73  includes a folding release handle  72 , which when released, allows the angled frame member  73  and head tube  71  to fold down against the base plate  24  about a pin  24   a  for compact storage or transportation of the scooter. 
         [0031]    Center wheel axle holes  74  in the step pad connectors  16  receive the axles  38 . Outer pivot rod holes  76  and rocker bar holes  80  receive the pins  18  to pivotally connect the rocker bars  14  to the step pad connectors. Center pivot rod holes  78  and rocker fork holes  82  receive pins  22  to pivotally connect the rocker bars  14  to the rocker fork  20 . 
         [0032]    The center frame member  84  is connected to the sprocket tube  32  at a rear end and to the angled frame member  73  at a front end, and carries the rods  52 , chain posts  56 , and rear guide wheel axles  44 . 
         [0033]    On each side of the scooter the two bars  14 , the connectors  16  and the center fork  20  and the pinned connections  18 ,  22 , between these four members create a “four bar linkage” that keeps the relative motion of each step pad  12  substantially vertical, wherein the flat upper surface of the step pad  12  remains horizontal. 
         [0034]    In operation, when a first side step pad is depressed, the rocker bars  14  force the opposite, second side step pad to rise ( FIG. 3 ). Rising of the second side step pad  12  causes the chain  62  on that side to be drawn beneath the guide wheel  42  and over the top of the sprocket  34  toward the guide wheel  42 . This movement of the chain  62  over the sprocket  34  causes the drive wheel  30  to rotate forward (counterclockwise as shown in  FIG. 3 ). Below the center guide wheel  36 , the straight length of the chain  62  and cord  64  are drawn from the pulley  48  toward the sprocket  34 . 
         [0035]    On the other side of the scooter, the first step pad is lowered and the cord  64  pulls the lower straight run of chain  62  from the sprocket  34  toward the pulley  48  and takes up all slack in the chain caused by the lowering of the step pad  12 . However, the sprocket  34  is a one-way transmission sprocket which causes the sprocket  34  to free wheel with respect to the drive wheel in the rear direction (clockwise in  FIG. 3 ). 
         [0036]    Thus, the back and forth oscillation of the chains  62  and the one direction transmission sprockets  34  cause the net effect to be a forward only propulsion of the scooter. 
         [0037]      FIGS. 3A and 4A  illustrate a modification of the structure of  FIGS. 2-6  in that the parts  52  and  56  have been combined in function, eliminating the part  52 . Horizontal guide wheels  48  are carried on horizontal wheel posts  54  which now extend from the chain posts  56 . Chain posts  56  receive chain bolts  58  which secure ends of the chains  62  to the posts  56  by chain bolt nuts  60 .  FIG. 4A  also indicates that bearings  32 B have been added to support the axle  28  within the sprocket tube  32 . 
         [0038]      FIGS. 7-9  illustrate an alternate step-propelled scooter  86 . Like elements carry the same reference numbers. In this embodiment, a large bevel gear  90  and two small bevel gears  92  are meshed to change the rotary axis of the bevel gear  90  degrees to drive alternate rear wheels  94 . An alternate rear wheel axle  96  is journaled by one-way bearings  98  and axle guides  100  which are supported by a frame member  88 . One-way bearings  98  are described for example in U.S. Pat. No. 7,581,742, or by analogy, the wheel hubs described in U.S. Pat. Nos. 4,593,799; 3,010,553; 3,709,341; 8,556,055, all herein incorporated by reference to the extent not inconsistent with the present disclosure. The frame member  88  would extend forward to connect to the angled frame member  73  as per the prior described embodiment. A bevel gear drive shaft  102  drives the large bevel gear. The drive shaft  102  is fixed to the bottom rocker arm  14 , replacing the bottom axle  22  of the prior embodiment, such that rocking motion of the arms  14  causes the axle  102  to reciprocally rotate or rock. The frame member  88  includes an opening  88   a  to accommodate the large bevel gear  90 . 
         [0039]      FIGS. 10 and 11  illustrate a further alternate step-propelled scooter  104 . A rear frame  106  supports a right side one-way sprocket  108  that is meshed with a right side driven sprocket  110  via a right side endless chain  112 . The one-way sprocket  108  would have a hub for freewheeling and one direction propulsion the same as the prior described sprockets  34 . A right side axle  114  is journaled by a right side axle guide  116  and is connected to the output of the right side bevel gear  92  and to the right side sprocket  108 . The right side driven sprocket  110  is fixed to an axle  115  that is fixed to the wheels  94  to rotate the wheels for forward movement of the scooter. A left side arrangement (not shown) is provided in mirror image fashion to the right side arrangement. It includes a left side sprocket  108 , a left side driven sprocket  110 , a left side endless chain  112 , a left side axle  114  and a left side axle guide  116 . The left side axle is connected to an output of the left side bevel gear  92 . The left side driven sprocket  110  is connected to the axle  115  that is fixed to the wheels  94  to rotate the wheels for forward movement of the scooter. 
         [0040]      FIGS. 12-14  illustrate an accessory for use with any of the above scooter embodiments. A stand  200  for stationary use of the scooter lifts the wheels  30  of the scooter off the ground or floor G by supporting the sprocket tube  32  to render the scooter effectively immobile during use. In this instance the scooter can be used as a stationary exercise device. The stand  200  is advantageously formed of a bent metal tube. A bent ½ inch to 1 inch steel tube would probably be sufficient. The stand  200  includes linear floor-supported portions  206   a ,  206   b , extending upward into respective serpentine portions  208   a ,  208   b , extending forward into respective concave cradle portions  210   a ,  210   b . A lateral inverted U-shaped brace portion  212  connects the rear of the floor-supported portions  206   a ,  206   b . The serpentine portions  208   a ,  208   b  allow the floor-supported portions  206   a ,  206   b  to be located in front of, below, and behind the vertical load of the scooter exerted on the cradle portions  210   a ,  210   b . This provides a more stable support base for the stand  200  to support the scooter. The cradle portions  210   a ,  210   b  are shaped to allow the sprocket tube  32  to be inserted in a forward direction and then move slightly downward to keep the sprocket tube  32  secure in the cradle portions, resisting rearward retraction and dislodgement 
         [0041]    From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. 
         [0042]    All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein, to the extent that the references are not inconsistent with the present disclosure.