Abstract:
An exercise apparatus includes a crank rotatably mounted on a frame, and a connector link rotatably interconnected between the crank and a foot supporting link. The entire connector link is constrained to pivot about a fixed point while a portion of the connector link rotates together with the crank. The location of the fixed point is selectively adjustable. A discrete portion of the foot supporting link is constrained to move in a reciprocal path relative to the frame. The reciprocal path is also selectively adjustable.

Description:
FIELD OF THE INVENTION 
     The present invention relates to exercise methods and apparatus and more particularly, to exercise equipment which facilitates exercise through a curved path of motion. 
     BACKGROUND OF THE INVENTION 
     Exercise equipment has been designed to facilitate a variety of exercise motions. For example, treadmills allow a person to walk or run in place; stepper machines allow a person to climb in place; bicycle machines allow a person to pedal in place; and still other machines allow a person to skate and/or stride 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 typically uses a linkage assembly to convert a relatively simple motion, such as circular, into a relatively more complex motion, such as elliptical. Despite many such advances in the art, room for improvement remains. 
     SUMMARY OF THE INVENTION 
     The present invention may be seen to provide a novel linkage assembly and corresponding exercise apparatus suitable for linking circular motion to relatively more complex, generally elliptical motion. On a preferred embodiment, for example, left and right connector links are rotatably interconnected between respective cranks and intermediate portions of respective foot supports, and are constrained to pivot in their entirety about a common pivot axis on a floor engaging frame. The foot supports have first ends pivotally connected to respective rocker links which pivot about a common rocker axis on the frame. Opposite, second ends of the foot supporting links are sized and configured to support a person&#39;s feet. The arrangement is such that the person&#39;s feet move through elliptical paths which may be adjusted by selectively relocating the pivot axis and/or the rocker axis. Additional features of the present invention may become more apparent from the more detailed description set forth below. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     With reference to the Figures of the Drawing, wherein like numerals represent like parts and assemblies throughout the several views, 
     FIG. 1 is a side view of an exercise apparatus constructed according to the principles of the present invention and configured for foot movement through a first path; 
     FIG. 2 is a side view of the exercise apparatus of FIG. 1 configured for foot movement through a second path; 
     FIG. 3 is a side view of the exercise apparatus of FIG. 1 configured for foot movement through a third path; 
     FIG. 4 is a side view of the exercise apparatus of FIG. 1 configured for foot movement through a fourth path; 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     An exercise apparatus constructed according to the principles of the present invention is designated as  100  in FIGS. 1-4. The exercise apparatus  100  generally includes a linkage assembly which moves relative to a frame  110  in a manner that links rotation of left and right cranks  120  to generally elliptical motion of left and right foot supporting members  160 . The term “elliptical motion” is intended in a broad sense to describe a closed path of motion having a relatively longer first axis and a relatively shorter second axis (which is perpendicular to the first axis). 
     The frame  110  is designed to rest upon a floor surface and includes frame portions or members  114 ,  115 ,  118 , and  119 . A user interface  111  is mounted on an upper portion of the frame  110  and within reach of a person  90  standing on the foot supporting members  160 . The interface  111  may be configured to perform a variety of functions, including (1) displaying information to the user, including (a) exercise parameters and/or programs, (b) the current parameters and/or currently selected program, (c) the current time, (d) the elapsed exercise time, (e) the current speed of exercise, (f) the average speed of exercise, (g) the number of calories burned during exercise, (h) the simulated distance traveled during exercise, and/or (i) material transmitted over the internet; (2) allowing the user to (a) select or change the information being viewed, (b) select or change an exercise program, (c) adjust the resistance to exercise, (d) adjust the range of exercise motion, and/or (e) adjust the orientation of exercise motion. 
     The apparatus  100  is generally symmetrical about a vertical plane extending lengthwise through the frame  110 , the only exceptions being the members interconnected between opposite side parts and the relative orientation of certain parts on opposite sides of the linkage assembly. In FIGS. 1-4, only the “right-hand” components are shown, with the understanding that similar “left-hand” components are one hundred and eighty degrees out of phase with the depicted components. 
     On each side of the linkage assembly, a crank  120  is rotatably mounted on the frame  110 . An upper end of a first telescoping member  132  is rotatably connected to the crank  120  (at connection point  123 ), and a lower end of the first telescoping member  132  is pivotally connected to an intermediate portion of the foot supporting member  160  (at connection point  163 ). A lower end of a second telescoping member  134  is inserted in the upper end of the first telescoping member  132  and movable in telescoping fashion relative thereto. Rollers may be rotatably mounted on one or both of the telescoping members  132  and  134  to facilitate the telescoping motion. An opposite, upper end of the second telescoping member  134  is pivotally connected to a first end of a first support link  140  (at connection point  143 ). An opposite, second end of the first support link  140  is pivotally connected to the frame member  114  (at connection point  141 ). An intermediate portion of the first support link  140  is pivotally connected to a rod end of an actuator  150  (at connection point  145 ). An opposite, cylinder end of the actuator  150  is pivotally connected to the frame member  115  (at connection point  151 ). Only one actuator  150  is provided to adjust both the right and left first support links  140 . 
     The foot supporting member  160  has a cantilevered, rearward end  166  which is sized and configured to support a person&#39;s foot. An opposite, forward end of the foot supporting member  160  is pivotally connected to a lower end of a rocker link  170  (at connection point  167 ). An opposite, upper end of the rocker link  170  is pivotally connected to a second support link  180  (at connection point  187 ). The second support link  180  is pivotally connected to the frame member  118  (at connection point  181 ). The second support link  180  is also pivotally connected to a rod end of an actuator  190  (at connection point  189 ). An opposite, cylinder end of the actuator  190  is pivotally connected to the frame member  119  (at connection point  191 ). Only one actuator  190  is provided to adjust both the right and left second support links  180 . 
     To use the apparatus  100 , a person stands with a respective foot on each of the foot supports  166  and begins moving his or her feet in striding fashion. The linkage assembly constrains the person&#39;s feet to move through elliptical paths while the cranks  120  rotate relative to the frame  110 . The elliptical paths are selectively adjustable by means of the actuators  150  and  190 , which may be operatively connected to the user interface  111  and responsive to control signals generated by a control program, the user, or another external influence. FIGS. 1-4 show the apparatus  100  configured for four different foot paths P 1 -P 4 , which are a function of the locations of the connection points  143  and  187  relative to the frame  110 . Stationary handles and/or movable handles may be mounted on the frame  110  and within reach of the person  90  standing on the foot supports  166 . The movable handles may be linked to the foot supports  166  and/or independently operable. Resistance to arm movement and/or leg movement may be provided in various known manners, and operatively connected to the user interface, as well. A flywheel may be linked to the cranks  120  to add inertia to the linkage assembly. 
     The apparatus  100  may be modified in a number of ways without departing from the scope of the present invention. For example, the rocker links  170  could be replaced by rollers mounted on the forward ends of the foot supporting links  160  and disposed within a generally horizontal race on the frame. Also, the telescoping links  134  could be replaced by rollers mounted on the ends of the first support links  140  and disposed within races on longer versions of the other telescoping links  132 . Additionally, one or both of the actuators  150  and  190  could be paired with an aligned race on the frame, rather than a pivoting support link, for purposes of relocating a respective connection point  143  or  187 . The race for the connection point  143  is preferably inclined rearwardly upward at an angle between thirty and forty-five degrees from vertical. The race for the connection point  187  is preferably inclined forwardly upward at an angle between fifteen and thirty degrees from horizontal. 
     Those skilled in the art will recognize that the present invention may also described in terms of methods (with reference to the foregoing embodiment  100 , for example). One such method involves linking rotation of a crank to generally elliptical movement of a foot supporting member. The method includes the steps of rotatably mounting a crank on a frame; rotatably connecting a link to the crank; constraining the link to pivot in its entirety about a pivot axis; rotatably connecting the link to an intermediate portion of a foot supporting member; and constraining an end of the foot supporting member to move in reciprocating fashion relative to the frame. The method may further include the step of changing the location of one or more of the connection points between the linkage assembly and the frame, in order to change the path traveled by the foot supporting member. 
     The present invention is not limited to the preferred embodiment disclosed herein, and persons skilled in the art are likely to recognize additional embodiments, modifications, and/or features which nonetheless fall within the scope of the present invention. For example, modifications may be made to the size, configuration, and/or arrangement of the linkage assembly components as a matter of design choice, and/or portions thereof may be replaced with mechanical equivalents. Recognizing that the foregoing description sets forth only some of the possible modifications and variations, the scope of the present invention is to be limited only to the extent of the claims which follow.