Abstract:
An elliptical motion exercise apparatus may provide a novel linkage assembly suitable for linking circular motion to relatively more complex, generally elliptical motion. Left and right cranks may be rotatably mounted on a frame. A force receiving member may be movably connected between a handle bar rocker and left and right crank assemblies in such a manner that the force receiving member moves through paths of motion which are fixed, adjustable or variable.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/464,226, filed Mar. 1, 2012, which application is incorporated herein in its entirety by reference. 
    
    
     BACKGROUND 
     The present invention relates to fitness machines, and in particular a fitness machine which constrains the user&#39;s foot and/or arm to travel along a variable or fixed foot path. 
     Exercise equipment has been designed to facilitate a variety of exercise motions (including treadmills for walking or running in place; stepper machines for climbing in place; bicycle machines for pedaling in place; and other machines for skating and/or striding in place. Yet another type of exercise equipment has been designed to facilitate relatively more complicated exercise motions and/or to better simulate real life activity. Such equipment converts a relatively simple motion, such as circular, into a relatively more complex motion, such as elliptical. Despite various advances in the elliptical exercise category, room for improvement remains. 
     SUMMARY 
     An elliptical motion exercise apparatus may provide a novel linkage assembly suitable for linking circular motion to relatively more complex, generally elliptical motion. Left and right cranks may be rotatably mounted on a frame. A force receiving member may be movably connected between a handle bar rocker and left and right crank assemblies in such a manner that the force receiving member moves through paths of motion which are fixed, adjustable or variable. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the above recited features, advantages and objects of the present invention are attained can be understood in detail, a more particular description of the invention briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. 
       It is noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
         FIGS. 1 ,  2  and  3  depict a side view of an embodiment of an exercise apparatus illustrating a relatively large range of motion in a closed path. 
         FIGS. 4 and 5  depict a side view of an embodiment of an exercise apparatus illustrating a relatively small range of motion in a closed path. 
         FIG. 6  depicts an enlarged perspective view of an embodiment of a cross-connect member that may interconnect the handle bar rockers of an exercise apparatus to move in dependent fashion relative to one another. 
     
    
    
     DETAILED DESCRIPTION 
     Elliptical motion exercise apparatus may link rotation of left and right cranks to generally elliptical motion of respective left and right foot supports. The term “elliptical motion” is intended in a broad sense to describe a closed path of motion having a relatively longer major axis and a relatively shorter minor axis. In general, displacement of the cranks move the foot supports in a direction coincidental with one axis of the elliptical path, and displacement of crank driven members move the foot supports in a direction coincidental with the other axis. A general characteristic of elliptical exercise apparatus may be that the crank diameter determines the length of one axis, but does not determine the length of the other axis. As a result of this feature, a user&#39;s feet may travel through a generally elliptical path having a desirable aspect ratio, and the apparatus that embody this technology may be made relatively more compact, as well. The embodiments shown and/or described herein are generally symmetrical about a vertical plane extending lengthwise through a floor-engaging base (perpendicular to the transverse ends thereof). In general, the “right-hand” components are one hundred and eighty degrees out of phase relative to the “left-hand” components. Like reference numerals are used to designate both the “right-hand” and “left-hand” parts, and when reference is made to one or more parts on only one side of an apparatus, it is to be understood that corresponding part(s) are disposed on the opposite side of the apparatus. Also, to the extent that reference is made to forward or rearward portions of an apparatus, it is to be understood that a person can typically exercise on such apparatus while facing in either direction relative to the linkage assembly. 
     Referring first to  FIG. 1 , an embodiment of an elliptical exercise apparatus is generally identified by the reference numeral  100 . The apparatus  100  includes a frame  10  that is designed to rest upon a floor surface. The frame  10  may include a generally I-shaped base  12 . A forward stanchion  14  extends upward from a forward end of the base  12  and a rearward stanchion  16  extends upward from the base  12  proximate an opposite, rearward end of the base  12 . 
     A linkage assembly may be movably mounted on the frame  10 . On each side of the apparatus  100 , the linkage assembly may include a handle bar rocker  18 , a force receiving member  20  and a crank assembly that may include a crank  22 , a connector link  24 , a rocker link  26  and a sinking crank  28 . The crank  22  is keyed to a common shaft rotatably mounted on the rear stanchion  16  at bearing  30  by means known in the art. The connector link  24  is pivotally connected to the crank  22  at a radially displaced pin  32  secured to the crank  22 . A first end of the connector link  24  is rotatably connected to the rocker link  26  at bearing  34 . The opposite end of the rocker link  26  is pivotally connected to the frame  12  at bearing  36 . A second end of the connector link  26  is rotatably connected to the sinking crank  28  at bearing  29 . 
     The force receiving member  20  may include a proximal end connected to the lower end of the handle bar rocker  18  at bearing  38 . The handle bar rocker  18  is rotatably connected to the forward stanchion  14  at bearing  42 . An upper end  44  of the handle car rocker  18  is sized and configured for grasping by a person standing on the force receiving member  20 . 
     A distal end of the force receiving member  20  is rotatably connected to an end of the sinking crank  28  at bearing  25 . The proximal end of the force receiving member  20  is constrained to move in a generally reciprocal fashion relative to the frame  12 . An intermediate portion of the force receiving member  20  may be sized and configured to include a foot platform  40  to support a person&#39;s foot. Generally, the linkage assembly encourages the force receiving member  20  to travel through an elliptical path of motion having a selectively variable length. 
     The handle bar rockers  18  may be interconnected to move in dependent fashion in opposite directions relative to one another. A cross-connect member  50 , shown in  FIG. 6 , may be mounted on the forward stanchion  18  and rotatable relative thereto about a horizontal axis. Link members  52  or the like interconnect the right and left handle bar rockers  18  to the cross-connect member  50 . The link members  52  may comprise a rigid bar having spherical joints  54  at the ends thereof. Rotational resistance in the form of friction may be provided between the stanchion  14  and the cross-connect member  50 . Spring and/or damper resistance may also be provided between the cross member  50  and the stanchion  14 . 
     During use, a user may stand on the foot platforms  40  an initiate a walking, striding or jogging motion. The force applied by the user may be transmitted to the force receiving member  20  which may cause the sinking crank  28  to swing and may cause rotation of the crank  22 . This interaction may allow variable stride closed path motion of the force receiving member  20 . The sink crank  28  may swing within a range of motion in response to the user applied force transmitted to the force receiving member  20 .  FIGS. 1-3  depict a relatively large foot/arm range of motion allowing the foot pads  40  to travel along a relatively large path P 1 .  FIGS. 4 and 5  depict a relatively small foot/arm range of motion allowing the foot pads  40  to travel along a relatively short path P 2 . If a fixed path range of motion is desired, the sinking crank  28  may be locked to the connector link  24  by means known in the art such that the foot pads may travel along a non-variable fixed path. 
     While a preferred embodiment of the invention has been shown and described, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims which follow.