Elliptical exercise device with cam drive

Abstract

An elliptical exercise device has a frame and guide link pivotally attached thereto. A foot support link is pivotally connected to a lower attachment point of each guide link so that when the guide links pivot relative to the frame, foot receiving areas of the foot support links move in a path of travel having a horizontal component of motion. A cam drive has cams supported for rotation about an axis of rotation and pivoting arms each engaging one of the cams such that rotation of the cams causes movement of the pivoting arms. Flexible elements couple the foot support links to the pivoting arms such that rotation of the cams moves the foot receiving areas of the respective foot support links in a path of travel having a vertical component of motion. A crank and horizontal control links control pivoting of the guide links.

1 . An elliptical exercise device comprising:
 a frame configured to be supported on a horizontal surface, the frame having a first pivot axis defined thereon, the frame further having a forward portion forward of the first pivot axis and a rearward portion rearward of the first pivot axis;   a first and a second guide link each having a first and a second attachment point defined thereon, each guide link being pivotally attached, through its first attachment point, to the frame at the first pivot axis thereof, each of the guide links having a guide length defined between the first and second attachment point;   a first and a second foot support link each having a foot receiving area configured to support a user's foot thereupon, each foot support link being pivotally connected to the second attachment point of a respective one of the guide links so that when the guide links pivot relative to the frame, they each cause the respective foot receiving area to move in a path of travel having a horizontal component of motion, each foot support link further having a coupling point rearward of the respective pivotal connection to the respective guide link;   a cam drive having a first and second cam supported for rotation about an axis of rotation and a first and a second pivoting arm engaging the respective first and second cams such that rotation of the cams causes movement of the pivoting arms;   a first and a second vertical control guide disposed on the rearward portion of the frame, spaced from the first pivot axis;   a first and a second flexible element each coupling a respective one of the foot support links to a respective one of the pivoting arms of the cam drive, each flexible element having a first end connected to a respective one of the pivoting arms, a second end connected to the coupling point on the respective foot support link, and a midportion extending over a respective one of the vertical control guides on the frame such that rotation of the cams moves the foot receiving areas of the foot support links in a path of travel having a vertical component of motion;   each of the flexible couplings having a foot support portion extending between the coupling point on the respective foot support link and the respective vertical guide on the frame, the foot support portion being generally parallel to the respective guide link throughout the motion of the device, the foot support portion further having a length that is similar to the guide length when the respective foot support link is at a midpoint of vertical travel; and   the respective first attachment point, second attachment point, guide on the frame and coupling point on the foot support portion generally define a parallelogram when the respective foot support link is at the midpoint of vertical travel;   a crank supported for rotation about an axis of rotation; and   a first and a second horizontal control link each having a first end connected to the crank and a second end connected to a respective one of the guide links such that as the crank rotates, the horizontal control links pivot the guide links about the first pivot axis, thereby moving the foot receiving areas of the foot support links in a path of travel having a horizontal component of motion, movement of each foot receiving area in the path of travel having a horizontal component of motion being generally out of phase with the movement in the path of travel having a vertical component of motion such that when the horizontal component of motion of each foot receiving area is at its forwardmost or rearwardmost limit, the vertical component of motion of the same foot receiving area is approximately midway between its uppermost and lowermost limit;   whereby the foot receiving area of each foot support link moves in a generally elliptical path when the cam portion rotates about the cam axis.   
     
     
         2 . An elliptical exercise device in accordance with  claim 1 , wherein the vertical control guides are spaced from the first pivot axis by a distance of a 6 or more inches. 
     
     
         3 . An elliptical exercise device in accordance with  claim 1 , wherein each of the cams has a generally non-circular shape. 
     
     
         4 . An elliptical exercise device in accordance with  claim 1 , wherein the pivoting arms each have a pivot end, an opposite control end, and a midportion therebetween, the pivot arms each further having a follower connected to the midportion, each follower contacting an outer surface of a respective one of the cams, the first end of each of the flexible elements being connected to the control end of the respective one of the pivoting arms. 
     
     
         5 . An elliptical exercise device in accordance with  claim 4 , wherein each pivoting arm is generally horizontal with the pivot end being forward of the control end, each flexible element extending generally vertically from the control end of the respective pivoting arm 
     
     
         6 . An elliptical exercise device in accordance with  claim 5 , further having a first and second forward pulley and a first and second lower pulley, each flexible element extending downwardly from the first end, wrapping under the respective lower pulley, extending upwardly and wrapping over the forward pulley, and extending rearwardly to the respective vertical control guide. 
     
     
         7 . An elliptical exercise device in accordance with  claim 4 , wherein each pivoting arm is generally vertical with the pivot end being lower than the control end, each flexible element extending generally horizontally and rearwardly from the control end of the respective pivoting arm. 
     
     
         8 . An elliptical exercise device in accordance with  claim 1 , wherein the horizontal control links are each adjustably connected to the crank or the respective guide link so as to adjust the range of horizontal motion. 
     
     
         9 . An elliptical exercise device in accordance with  claim 1 , wherein the guide links further comprise hand portions extending upwardly from the first attachment point. 
     
     
         10 . An elliptical exercise device in accordance with  claim 1 , wherein:
 a forward end of each foot support link is pivotally interconnected with the second attachment point of the respective guide link and a rearward end of each foot support link defines the foot receiving area; and   the coupling point on each foot support link being defined between the forward and rearward ends.   
     
     
         11 . An elliptical exercise device in accordance with  claim 1 , wherein each vertical control guide comprises a pulley rotationally mounted on the frame 
     
     
         12 . An elliptical exercise device in accordance with  claim 1 , further comprising an adjustment mechanism for adjusting a range of vertical travel, the adjustment mechanism comprising a first sliding collar coupled to the first pivoting arm and a second sliding collar coupled to the second pivoting arm, the first end of each of the flexible elements being coupled to the sliding collar of the respective pivoting arm, the adjustment mechanism further comprising an actuator operable to move the sliding collars on the pivoting arms. 
     
     
         13 . An elliptical exercise device in accordance with  claim 1 , wherein the flexible element are cables. 
     
     
         14 . An elliptical exercise device comprising:
 a frame configured to be supported on a horizontal surface, the frame having a first pivot axis defined thereon, the frame further having a forward portion forward of the first pivot axis and a rearward portion rearward of the first pivot axis;   a first and a second guide link each having a first and a second attachment point defined thereon, each guide link being pivotally attached, through its first attachment point, to the frame at the first pivot axis thereof, each of the guide links having a guide length defined between the first and second attachment point;   a first and a second foot support link each having a foot receiving area configured to support a user's foot thereupon, each foot support link being pivotally connected to the second attachment point of a respective one of the guide links so that when the guide links pivot relative to the frame, they each cause the respective foot receiving area to move in a path of travel having a horizontal component of motion, each foot support link further having a coupling point rearward of the respective pivotal connection to the respective guide link;   a cam drive having a first and second cam supported for rotation about an axis of rotation and a first and a second pivoting arm engaging the respective first and second cams such that rotation of the cams causes movement of the pivoting arms;   a first and a second vertical control guide disposed on the rearward portion of the frame, the vertical control guides being spaced from the first pivot axis by a distance of 6 or more inches;   a first and a second flexible element each coupling a respective one of the foot support links to a respective one of the pivoting arms of the cam drive, each flexible element having a first end connected to a respective one of the pivoting arms, a second end connected to the coupling point on the respective foot support link, and a midportion extending over a respective one of the vertical control guides on the frame such that rotation of the cams moves the foot receiving areas of the respective foot support links in a path of travel having a vertical component of motion;   a crank supported for rotation about an axis of rotation; and   a first and a second horizontal control link each having a first end connected to the crank and a second end connected to a respective one of the guide links such that as the crank rotates, the horizontal control links pivot the guide links about the first pivot axis, thereby moving the foot receiving areas of the foot support links in a path of travel having a horizontal component of motion, movement of each foot receiving area in the path of travel having a horizontal component of motion being generally out of phase with the movement in the path of travel having a vertical component of motion such that when the horizontal component of motion of each foot receiving area is at its forwardmost or rearwardmost limit, the vertical component of motion of the same foot receiving area is approximately midway between its uppermost and lowermost limit;   whereby the foot receiving area of each foot support link moves in a generally elliptical path when the cam portion rotates about the cam axis.   
     
     
         15 . An elliptical exercise device in accordance with  claim 14 , wherein each of the cams has a generally non-circular shape. 
     
     
         16 . An elliptical exercise device in accordance with  claim 14 , wherein:
 a forward end of each foot support link is pivotally interconnected with the second attachment point of the respective guide link and a rearward end of each foot support link defines the foot receiving area; and   the coupling point on each foot support link being defined between the forward and rearward ends.   
     
     
         17 . An elliptical exercise device in accordance with  claim 14 , wherein the pivoting arms each have a pivot end, an opposite control end, and a midportion therebetween, the pivot arms each further having a follower connected to the midportion, each follower contacting an outer surface of a respective one of the cams, the first end of each of the flexible elements being connected to the control end of the respective one of the pivoting arms. 
     
     
         18 . An elliptical exercise device in accordance with  claim 17 , wherein each pivoting arm is generally horizontal with the pivot end being forward of the control end, each flexible element extending generally vertically from the control end of the respective pivoting arm 
     
     
         19 . An elliptical exercise device in accordance with  claim 18 , further having a first and second forward pulley and a first and second lower pulley, each flexible element extending downwardly from the first end, wrapping under the respective lower pulley, extending upwardly and wrapping over the forward pulley, and extending rearwardly to the respective vertical control guide. 
     
     
         20 . An elliptical exercise device in accordance with  claim 17 , wherein each pivoting arm is generally vertical with the pivot end being lower than the control end, each flexible element extending generally horizontally and rearwardly from the control end of the respective pivoting arm. 
     
     
         21 . An elliptical exercise device in accordance with  claim 14 , wherein the flexible element are cables.