Abstract:
An exercise apparatus includes a frame configured to rest on a floor surface; left and right cranks rotatably mounted on the frame; left and right first rocker links pivotally mounted on the frame; left and right drawbar links pivotally interconnected between respective cranks and respective first rocker links; left and right second rocker links pivotally mounted on the frame; and left and right foot links supported by respective cranks and respective rocker links. On one embodiment, the second rocker links are selectively pinned to respective first rocker links to configure the apparatus for elliptical striding exercise, and the second rocker links are alternatively pinned to the frame to configure the apparatus for arcuate stepping exercise. On another embodiment, adjustable length members are interconnected between respective second rocker links and respective first rocker links to accommodate variable elliptical striding motion.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application Ser. No. 61/070,215, filed. Mar. 20, 2008, which application is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to exercise methods and apparatus, and more specifically, to exercise equipment that guides a person&#39;s feet through generally elliptical paths 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 step or climb in place; bicycle machines allow a person to pedal in place; and still other machines allow a person to ski 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 the human striding motion. This equipment typically uses a linkage assembly to convert a relatively simple motion, such as circular, into a relatively more complex motion, such as elliptical. Examples of these elliptical motion exercise machines are disclosed in U.S. Pat. No. 4,185,622 to Swenson; U.S. Pat. No. 5,279,529 to Eschenbach; U.S. Pat. No. 5,383,829 to Miller; U.S. Pat. Nos. 5,540,637 to Rodgers, Jr.; 6,196,948 to Stearns et al.; and U.S. Pat. No. 6,468,184 to Lee, all of which are incorporated herein by reference to help provide context for better understanding of the subject invention. 
     SUMMARY OF THE INVENTION 
     Generally speaking, the present invention provides novel linkage assemblies and corresponding exercise apparatus that facilitate elliptical exercise motion of a variable nature. On a first embodiment, left and right amplifying rocker links are selectively pinned to respective left and right cranks to generate generally elliptical striding motions, and the rocker links are alternatively pinned to the frame to generate arcuate stepping motions. On a second embodiment, left and right adjustable length members are interconnected between respective left and right rocker links and respective left and right drawbar linkages to generate generally elliptical striding paths that vary in length as a function of the length of the adjustable length members. Additional features and/or advantages of the present invention will become apparent from the more detailed description that follows. 
    
    
     
       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 to operate in a striding mode; 
         FIG. 2  is a side view of the exercise apparatus of  FIG. 1 , but adjusted to generate a relatively shorter exercise path while still in the striding mode; 
         FIG. 3  is a side view of the exercise apparatus of  FIG. 1 , but adjusted to generate a still shorter exercise path while still in the striding mode; 
         FIG. 4  is a side view of the exercise apparatus of  FIG. 1  configured to operate in a stepping mode; 
         FIG. 5  is a side view of a second exercise apparatus constructed according to the principles of the present invention; and 
         FIG. 6  is a side view of the exercise apparatus of  FIG. 5 , but adjusted to generate a relatively shorter exercise path. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention involves elliptical motion exercise machines, and methods that link so-called “elliptical motion” of left and right foot supports to rotation of left and right cranks and/or arcuate motion of left and right handlebars. The term “elliptical motion” is intended in a broad sense to describe a closed-loop path of motion having a relatively longer, major axis and a relatively shorter, minor axis (which extends perpendicular to the major axis). In general, the present invention may be said to directly use displacement of the cranks to move the foot supports in a direction coincidental with the minor axis, and indirectly use displacement of the cranks to move the foot supports in a direction coincidental with the major axis. As a result, the length of the minor axis is more directly a function of the crank diameter, while the length of the major axis is not so restricted. Moreover, as further explained below, under certain circumstances the exercise motion may be converted into an arcuate stepping motion by limiting movement of the foot supports to pivoting in a generally vertical direction. 
     A first embodiment of the present invention is designated as  100  in  FIGS. 1-4 . The exercise apparatus  100  may be described in terms of a frame  99 , and left and right linkage assemblies movably mounted on the frame  99 . The apparatus  100  is generally symmetrical about a vertical plane extending lengthwise through the frame  99 . The linkage assembly components on the left side of the machine are preferably one hundred and eighty degrees out of phase relative to their opposite side counterparts. 
     The frame  99  includes a floor engaging base, a rearward stanchion that extends upward from a rearward end of the base, and a forward stanchion that extends upward from an opposite, forward end of the base. A conventional user interface (not shown) may be mounted on top of the forward stanchion to perform a variety of functions, including (1) displaying information to the user regarding items such as (a) exercise parameters and/or programs, (b) the current parameters and/or a 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) data transmitted over the internet; and (2) allowing the user to (a) select or change the information being viewed, (b) select or change an exercise program, (c) adjust the speed of exercise, (d) adjust the resistance to exercise, (e) adjust the orientation of the exercise motion, and/or (f) immediately stop the exercise motion. 
     A laterally extending shaft or axle is rotatably mounted on the rearward stanchion, thereby defining a crank axis, and left and right cranks  10  are secured to respective ends of the shaft. The left and right cranks  10  are keyed to the shaft and thereby constrained to rotate together relative to the frame  99 . As a matter of design choice, various known inertia altering devices, including flywheels and/or resistance brakes, for example, may be connected to the cranks, either directly or in “stepped-up” fashion using a belt and different diameter drums. 
     In addition to a respective crank  10 , each linkage assembly also includes a first rocker link  50  that is pivotally mounted on a laterally extending shaft  45  on an upper portion of the forward stanchion, and a second rocker link  40  that is also pivotally mounted on the shaft  45 . On an alternative embodiment, the first rocker links pivot about a first pivot axis relative to the frame, and the second rocker links pivot about a discrete, second pivot axis relative to the frame. On another alternative embodiment, the first rocker links are pivotally mounted on respective second rocker links, instead of the frame. 
     An upper distal end  44  of each second rocker link  40  is sized and configured for grasping. As shown in  FIG. 4 , holes  56  extend through the first rocker links  50 , and holes  46  extend through the second rocker links  40 . The holes  56  and  46  are disposed at a common radius from the shaft  45 , and thus, are rotatable into alignment with one another. As shown in  FIGS. 1-3 , a respective fastener  80  is selectively inserted through a respective set of aligned holes  56  and  46  to selectively lock a respective first rocker link  56  relative to a respective second rocker link  46 . 
     As shown in  FIG. 2 , holes  49  extend through the second rocker links  50 , and holes  94  extend through the stanchion, proximate its upper end. The holes  49  and  94  are disposed at a common radius from the shaft  45 , and thus, the holes  49  are rotatable into alignment with the holes  94 . As shown in  FIG. 4 , a respective fastener  80  is removed from holes  56  and  46  and selectively inserted through a respective set of holes  49  and  94  to selectively lock a respective second rocker link  40  to the frame  99 . Each fastener  80  may take various known forms, including a pin with a spring-biased ball disposed inside its distal end, or a threaded bolt, for example. 
     Each linkage assembly also includes a drawbar link  30  having a rearward end pivotally connected to a respective crank  10 , and a forward end pivotally connected to a respective first rocker link  50 . More specifically, the forward end of each drawbar link  30  is pivotally connected to a respective adjustment link  60  at a respective tube  65 . In turn, each adjustment link  60  is pivotally connected to a respective first rocker link  50  at a respective pin  62 . A series of holes  55  extend through each first rocker link  50 , and both the respective holes  55  and a respective pivot tube  65  are disposed at a common radius from a respective pivot pin  62 . A fastener, which could be similar to the fastener  80 , is inserted through a respective tube  65  and an aligned one of the holes  55  to secure a respective adjustment link  60  in a desired position relative to a respective first rocker link  50 . As further discussed below, the adjustment links  60  are secured in relatively higher holes  55  to create a relatively greater stride length (see  FIG. 1 ), and the adjustment links  60  are secured in relatively lower holes  55  to generate a relatively shorter stride length (see  FIG. 3 ). Each first rocker link  50  and associated drawbar link  30  may be described collectively as a drawbar linkage, and each associated fastener  80  may be described as a means for adjusting to what extent a respective rocker link pivots in response to motion of a respective said drawbar linkage. 
     Persons skilled in the art will recognize that actuators, for example, may be used instead of the fasteners  80 , to reposition the adjustment links  60 . On such an alternative embodiment, the actuators may be operated in response to a control signal that is based on a user pushing a button, a change in a selected exercise program, or a detected change in exercise performance. For example, the detected change in exercise performance may be a change in the user&#39;s heart rate, as detected by a monitor, or a change in the user&#39;s applied force to one of the linkage assembly members, as detected by a strain gauge, or a change in the user&#39;s level of exertion, as detected by operational characteristics of a resistance device (such as an eddy current brake) connected to the cranks  10 . 
     Each linkage assembly also includes a foot supporting link  20  having a rearward end that is sized and configured to support the foot of a person in a standing position. A roller  15  is rotatably mounted on each crank  10 , and each foot supporting link  20  is disposed on top of a respective roller  15 . On the depicted embodiment  100 , a common shaft  5  supports both a respective roller and a respective drawbar link  30 . However, the present invention is not limited to this particular arrangement. As shown in U.S. Pat. No. 6,629,909 to Stearns et al., which is incorporated herein by reference, a crank extension link may be used to provide two separate crank connection points (e.g. see part 190 in FIG. 16 of said patent). This same patent also shows various ways to arrange the linkage assembly components laterally relative to one another on the present invention (e.g. see FIGS. 20A-20J of said patent). 
       FIG. 1  shows the machine  100  configured for relatively long elliptical striding motion. In this regard, each pivot tube  65  is secured in alignment with a respective uppermost hole  55  (relatively close to the pivot shaft  45 ). A point on each foot support  20  travels through a generally elliptical path designated as P 1 , and a point on each handle  44  travels through an arcuate path designated as Q 1 . 
       FIG. 2  shows the machine  100  configured for intermediate elliptical striding motion. In this regard, each pivot tube  65  is secured in alignment with a respective intermediate hole  55  (relatively further from the pivot shaft  45 ). A point on each foot support  20  travels through a generally elliptical path designated as P 2 , and a point on each handle  44  travels through an arcuate path designated as Q 2 . 
       FIG. 3  shows the machine  100  configured for relatively short elliptical striding motion. In this regard, each pivot tube  65  is secured in alignment with a respective lowermost hole  55  (still further from the pivot shaft  45 ). A point on each foot support  20  travels through a generally elliptical path designated as P 3 , and a point on each handle  44  travels through an arcuate path designated as Q 3 . 
       FIG. 4  shows the machine  100  configured for arcuate stepping motion. In this regard, each first rocker link  50  is disconnected from a respective second rocker link  40 , and each second rocker link  40  is locked to the frame  99 . The position of each pivot tube  65  relative to the holes  55  is not relevant in this configuration (because each first rocker link  50  simply pivots back and forth independent of the second rocker links  40 ). A point on each foot support  20  travels through an arcuate path designated as P 4 , and the handles  44  remain stationary. 
     Another alternative embodiment of the present invention is designated as  200  in  FIGS. 5-6 . As suggested by the common reference numerals, the machine  200  is similar in many respects to the first embodiment  100 . In this regard, the machine  200  is different only to the extent that it operates in only a striding mode, and it provides a greater level of adjustability in stride length. 
     On each linkage assembly, an adjustable length member  90  has a cylinder end that is rotatably connected to a respective first rocker link  50  (at pivot joint  92 ), and an opposite, rod end that is rotatably connected to a respective second rocker link  40  (at pivot joint  94 ). On the depicted embodiment  200 , the adjustable length members are combination springs and dampers, such as the ones disclosed in U.S. Pat. No. 5,072,928 to Stearns, which is incorporated herein by reference. However, on an alternative embodiment, the adjustable length members are instead actuators that operate in response to a control signal (as described with reference to a previously described embodiment). 
       FIGS. 5 and 6  show the machine  200  configured to operate in an intermediate striding mode (like the first embodiment  100  as shown in  FIG. 2 ). The adjustable length members  90  accommodate variation in stride lengths within a range determined by the setting of the adjustable links  60 . When the adjustable length members are combination springs and dampers, the stride length varies as a function of changes in user force applied against one or more of the linkage assembly members.  FIG. 5  shows the adjustable length member  90  in a relatively contracted state, placing the pivot joint  65  relatively closer to the shaft  45  (for greater amplification effect), and thereby generating a relatively longer generally elliptical path P 5 , and a relatively longer arcuate path Q 5 .  FIG. 6  shows the adjustable length member  90  in a relatively extended state, placing the pivot joint  65  relatively further from the shaft  45  (for less amplification effect), and thereby generating a relatively shorter generally elliptical path P 6 , and a relatively shorter arcuate path Q 6 . As noted with reference to the embodiment  100 , each first rocker link  50  and associated drawbar link  30  may be described collectively as a drawbar linkage, in which case, each associated adjustable length member may be described as a means for adjusting to what extent a respective rocker link pivots in response to motion of a respective said drawbar linkage. 
     The present invention has been described with the understanding that persons skilled in the art will recognize additional embodiments, improvements, and/or applications that nonetheless fall within the scope of the invention. Therefore, the scope of the present invention should be limited only to the extent of the following claims.