Patent Publication Number: US-6991587-B1

Title: Elliptical exercise apparatus with adjustment

Description:
BACKGROUND OF THE INVENTION 
     1. Field 
     The present invention relates to a standup exercise apparatus that simulates walking, jogging and climbing with arm exercise. More particularly, the present invention relates to an exercise machine having separately supported pedals for the feet and arm exercise coordinated with the motion of the feet. 
     2. State of the Art 
     The benefits of regular exercise to improve overall health, appearance and longevity are well documented in the literature. For exercise enthusiasts the search continues for safe apparatus that provides full body exercise for maximum benefit in minimum time. 
     Recently, a new category of exercise equipment has appeared on the commercial market called elliptical cross trainers. These cross trainers guide the feet along a generally elliptical shaped curve to simulate the motions of jogging and climbing. Generally they use long cranks to generate a long foot stride having excessive pedal articulation. There is a need for an elliptical exercise machine capable of a similar long stride using a linkage to modify a shorter crank. 
     Standup pedal exercise combined with arm levers attached to the pedals is shown in Kummerlin et al. German Pat. No. 2,919,494 and in Geschwender U.S. Pat. No. 4,786,050. Standup pedal exercise coupled with oscillating swing arms is shown in Miller U.S. Pat. Nos. 5,242,343 and 5,383,829 and in Eschenbach U.S. Pat. No. 5,423,729. All of these exercise machines use pedals having two pedal pivots which are guided by a first circular guide path curve generated by a crank which rotates through one full revolution during a pedal cycle and a second arc guide path curve generated by a rocker link or track. 
     Eschenbach in U.S. Pat. No. 5,957,814 shows the use of an orbital link in a front drive elliptical design. Several rear drive elliptical cross trainers are shown by Eschenbach in U.S. Pat. Nos. 6,042,512 and 6,361,476. Rosenow in U.S. Pat. No. 6,217,486 and Arnold et al. in U.S. Pat. No. 6,238,321 show typical commercial rear drive elliptical cross trainers in use today. 
     Jarriel et al. in U.S. Des. Pat. No. 330,236 shows a pair of equal length cranks that guide a pedal for standup exercise. Eschenbach in U.S. Pat. No. 5,279,529 shows a double crank configuration to guide a pedal where each crank is a different length. Johnson in U.S. Pat. Nos. 5,387,167, 5,403,255, 5,647,821, 5,944,636, 6,120,417, 6,251,050, 6,746,377 and 6,755,769 displays pedals guided by two cranks of the same length and having different lengths. 
     Lee in U.S. Pat. Nos. 5,902,216 and 6,146,314 shows a pair of unequal length cranks to guide a pedal with arm exercise added. Jarvie in U.S. Pat. No. 5,792,028 also shows a pair of cranks with a linkage for striding. Rodgers in U.S. Pat. No. 5,529,555 shows a linkage with two cranks to generate an ellipse. 
     There is a need for a pedal operated exercise machine that can be safely operated in the standup position whereby the arms and legs can be exercised with the feet moving through a generally elliptical movement without excessive pedal articulation. There is also a need to adjust the stride length while maintaining less pedal articulation. 
     It is one objective of this invention to provide an elliptical pedal movement with a path generating linkage that provides a long stride with less pedal articulation. Excessive pedal articulation causes ankle stress. Another object of this invention is to provide an adjustable stride. 
     SUMMARY OF THE INVENTION 
     The present invention relates to the kinematic motion control of pedals which simulate running, climbing and cycling during several modes of operation. More particularly, apparatus is provided that offers variable intensity exercise through a leg operated cyclic motion in which the pedal supporting each foot is guided through successive positions during the motion cycle while a load resistance acts upon the mechanism. 
     The pedals are guided through an oblong or elongate curve motion while pedal angles vary during the pedal cycle to maintain the heel of the foot generally in contact with the pedal with less pedal articulation. As the foot is raised, the heel of the foot remains generally in contact with the inclining pedal for safer operation. Arm exercise is by arm levers coordinated with the mechanism guiding the foot pedals. 
     In the preferred embodiment, the apparatus includes a separate pedal for each foot, each pedal being extended by a foot support member and partially supported by an orbital oblong guide path at the first portion of the foot support member. The oblong guide path generating linkage has a first crank arm which completes one full revolution during a pedal cycle and is phased generally opposite the first crank arm for the other pedal through a crankshaft pivot axis attached to the framework. 
     An orbital link is connected to the first crank arm pivot configured so that all portions of the orbital link traverse orbital paths as the first crank arm rotates. This is accomplished by the addition of a connector link pivotally connected to the orbital link and to a second crank arm which rotates at the same speed as the first crank arm. The second crank arms can have a variable length which can cause the stride length to change. 
     A second portion of the foot support member is supported with a pivot by a guide link which is pivotally connected to the framework. As the crank arms are driven by foot motion, the pedals follows an elongate curve approximating an ellipse having less pedal articulation than other elliptical cross trainers having long crank arms. Alternately, the guide links can be replaced with guides in contact with rollers positioned on the foot support member. 
     Arm exercise is provided with handles pivotally connected to the framework and coordinated with the guide links. When the foot is forward, the handle corresponding to that foot is generally rearward. 
     Load resistance is imposed upon the crank arms through pulleys and belts from a flywheel and alternator. A control system regulates the load on the alternator to vary the resistance to exercise. The resistance can be varied during operation through a control system within easy reach of the operator. Other forms of load resistance such as friction, magnetic, air, belt, etc. may also be used. 
     Movement of the pedals cause the first portion of the foot support member to follow an elongate orbital path similar to an ellipse where the longer major axis of the ellipse is generally horizontal to provide the longer stride length. The shorter minor axis of the ellipse results in less pedal articulation. 
     In summary, this invention provides the operator with stable foot pedal support having motions that simulate running, climbing and cycling with very low joint impact and upper body exercise. The pedal motion exhibits a long stride with less pedal articulation common to other elliptical trainers for less ankle stress regardless of stride length. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a right side elevation view of the preferred embodiment of an exercise machine constructed in accordance with the present invention; 
         FIG. 2  is the rear view of the preferred embodiment shown in  FIG. 1 ; 
         FIG. 3  is is a side elevation view of the preferred embodiment shown in  FIG. 1  after a crank length adjustment; 
         FIG. 4  is a side view of the preferred embodiment shown in  FIG. 1  with an adjustable crank. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring to the drawings in detail, pedals  50  and  52  are shown in  FIGS. 1 and 2  in the most forward and rearward positions of the first embodiment. Pedals  50  and  52  are supported by foot support members  54  and  56  and traverse an elongate closed loop path  1 . Foot support members  54 , 56  are connected to guide links  58 , 60  at pivots  51 , 53  and connected to orbital links  24 , 26  at pivots  25 , 27 . Guide links  58 , 60  are connected to frame member  80  at pivots  55 , 57 . 
     Orbital links  24 , 26  are connected to crank arms  20 , 22  and connector links  34 , 36  at pivots  29 , 31 . Crank arms  20 , 22  are joined as generally opposed at pivot axis  43  to form a first crank. A second crank having crank arms  28 , 30  rotates about second pivot axis  41 . Connector links  34 , 36  are connected to second crank arms  28 , 30  at pivots  37 , 39 . Pulley  35  rotates with first crank arm  20  and pulley  33  rotates with second crank arm  28 . Belt  12  engages pulleys  33  and  35  to cause first crank arm  20  and second crank arm  28  to rotate at the same speed. Alternative pivot locations  5 , 11  on second cranks  28 , 30  provide for a variable length crank. 
     Each portion of orbital links  24 , 26  follow orbiting paths such as orbital path  6  traversed by pivots  25 , 27  and orbital path  4  traversed by pivots  29 , 31 . Orbital links  24 , 26 , first crank arms  20 , 22 , second crank arms  28 , 30 , and connector links  34 , 36  form a pair of path generating linkages configured to guide the first portion of the foot support member  54 , 56  along orbital path  6 . For this embodiment, note that path  6  followed by the end of foot support members  54 , 56  does not orbit first pivot axis  43  or second pivot axis  41 . 
     Handles  62 , 64  are attached to guide links  58 , 60  for arm exercise. Pulley  49  is attached to crank arms  20 , 22  and rotates about pivot axis  43  to drive alternator  45  and flywheel  13  through belts  17 , 19  and step-up pulley  47 . Alternator  45  is supported by frame  70  and is connected to controller  66  by wires  16 , 18  using conventional wiring (not shown). Controller  66  is attached to frame member  68  by support  96  and works with alternator  45  to provide variable resistance to exercise using conventional methods. A shroud  3  is shown with slots  7 , 9  to enclose the drive system to allow foot support members  54 , 56  to protrude. 
     Horizontal member  80  supports guide pivots  55 , 57  and is attached to frame member  70  by upright support  68 . First crank pivot axis  43  and second crank pivot axis  41  are supported by upright members  76 , 78  which are attached to frame member  70 . Cross members  72 , 74  are supported by the floor and attach to frame member  70 . Pulley  47  is supported by a pulley support (not shown) attached to frame member  70 . 
     The preferred embodiment is shown in  FIG. 3  where the second crank arms  28 , 30  have been lengthened with connector links  34 , 36  connected at pivot  5 . Orbital link  24  now has pivot  29  following elliptical curve  8  and pivot  25  follows elliptical curve  10 . Elliptical curve  10  is shorter in length than curve  6  resulting in a shorter stride curve  2  versus pedal curve  1  shown in  FIG. 1 . The forward end of the preferred embodiment, companion foot support member  56  and the companion path generating mechanism are not shown for clarity. 
       FIG. 4  shows a crank arm assembly as a typical means to adjust the length of second crank arms  28 , 30 . Threaded member  91  has pivot  37  on one end and is engaged with internally threaded member  95 . Internally threaded member  95  is allowed to rotate in covers  92  which is attached to second crank arm  28  by bolts  99 . The crank arm assembly rotates about second pivot axis  41 . Internally threaded member  95  has a hex end  93  to allow rotation for adjustment by a tool such as a socket (not shown). Turning of internally threaded member  95  will cause threaded member  91  to extend to pivot position  5  or by turning in reverse to contract to pivot position  11 . 
     Alternately, a stepping motor (not shown) can engage hex end  93  to adjust threaded member  91  automatically by control  66  when second crank arms  28 , 30  are stopped in the proper position. After adjustment, the stepping motor would retract out of the way. 
     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the claims, rather than by foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.