Elliptical exerciser

Abstract

An exercise machine includes a frame with a first axle rotatably about a first axis thereof and a pair of drive systems engage the first axle on opposite sides of the frame. Each of the drive systems includes a crank arm connected to the first axle for rotation about the first axis and a second axle defining a second axis and connected to the crank arm for rotation about the first axle. A lever arm is connected to the second axle for rotation about the second axis. A first link is rotatably connected at opposite locations thereon to the frame and the lever arm. A second link is rotatably connected to the lever arm opposite the first link. A third link is rotatably connected to the second link opposite to the lever arm and slidably engages the second axle.

What is claimed:  
     
         1 . An exercise machine comprising: 
 a frame;    a first axle supported by the frame and being rotatable about a first axis of the first axle; and    a pair of drive systems engaging the first axle on opposite sides of the frame, each of the drive systems having: 
 a crank arm connected to the first axle for rotation about the first axis;  
 a second axle defining a second axis and connected to the crank arm for rotation about the first axle;  
 a lever arm connected to the second axle for rotation about the second axis;  
 a first link rotatably connected at opposite locations thereon to the frame and the lever arm;  
 a second link rotatably connected to the lever arm opposite the first link; and  
 a third link rotatably connected to the second link opposite the lever arm and slidably engaging the second axle;  
 whereby the application of force by a user to the third link induces cyclic movement of the third link and rotates the crank arm to apply torque to the first axle, the cyclic movement being constrained by the second link and the second axle so that at least a portion of the third link moves in a substantially elliptical path.  
   
     
     
         2 . The exercise machine of  claim 1 , wherein the cyclic movement of each third link is further constrained by a fourth link rotatably connected at opposing locations thereon to the frame and the third link.  
     
     
         3 . The exercise machine of  claim 1 , wherein the fourth link is rotatably connected to the third link at respective ends of the fourth link and the third link.  
     
     
         4 . The exercise machine of  claim 1 , wherein the fourth link has an upright handle opposite the rotatable connection with the third link for gripping by a hand of the user.  
     
     
         5 . The exercise machine of  claim 4 , wherein the fourth link is rotatably connected to an upright portion of the frame intermediate the handle and the rotatable connection with the third link.  
     
     
         6 . The exercise machine of  claim 1 , wherein the first axle is connected to a mechanism that resists rotation thereof, whereby the user's applied force must overcome the resistance of the mechanism to move the third link.  
     
     
         7 . The exercise machine of  claim 6 , wherein the first axle is connected to a wheel for rotation thereof, and the rotation-resisting mechanism applies friction to the wheel.  
     
     
         8 . The exercise machine of  claim 6 , wherein the rotation-resisting mechanism includes a gear assembly through which the torque applied to the first axle is at least partially consumed.  
     
     
         9 . The exercise machine of  claim 1 , wherein the crank arms of the drive systems are connected to the first axle so as to be orientated 180° apart from each other, whereby the respective third link portions move through substantially elliptical paths 180° out of sync.  
     
     
         10 . The exercise machine of  claim 1 , wherein the second axle is fixed to the crank arm for movement therewith.  
     
     
         11 . The exercise machine of  claim 1 , wherein the second axle is rotatably connected to the crank arm for rotation about the second axis.  
     
     
         12 . The exercise machine of  claim 1 , wherein the lever arm is fixed to the second axle for movement therewith and includes a roller mounted for rotation thereon, the roller being slidably engaged by the third link.  
     
     
         13 . The exercise machine of  claim 1 , wherein the lever arm is rotatably connected to the second axle for rotation relative to the second axle.  
     
     
         14 . The exercise machine of  claim 1 , wherein the first link has first and second ends and is rotatably connected at its first and second ends to the lever arm and frame, respectively.  
     
     
         15 . The exercise machine of  claim 1 , wherein the second link has first and second ends and is rotatably connected at its first and second ends to the lever arm and the third link, respectively.  
     
     
         16 . The exercise machine of  claim 1 , wherein the lever arm has first and second ends and is rotatably connected at its first and second ends to the first link and second link, respectively.  
     
     
         17 . The exercise machine of  claim 1 , further comprising a foot pedal connected to each third link for engagement by a foot of a user so as to apply force to the third link, whereby the foot pedal moves in the substantially elliptical path.  
     
     
         18 . The exercise machine of  claim 17 , wherein the foot pedal is fixed to the third link for movement therewith.  
     
     
         19 . The exercise machine of  claim 18 , wherein the foot pedal is adjustably fixed to the third link so as to vary its position along the third link.  
     
     
         20 . The exercise machine of  claim 1 , wherein each drive system is configured such that the major axis of the substantially elliptical path lies in substantially horizontal plane and the minor axis of the substantially elliptical path lies in substantially vertical plane.  
     
     
         21 . The exercise machine of  claim 20 , wherein the major axis is at least four times the length of the minor axis.  
     
     
         22 . The exercise machine of  claim 21 , wherein the major axis is approximately six times the length of the minor axis.  
     
     
         23 . An exercise machine, comprising: 
 a frame; and    a pair of drive systems disposed on opposite sides of the frame, each of the drive systems having: 
 a crank arm rotatably connected to the frame at a location defining a first axis;  
 a lever arm rotatably connected to the crank arm at a location defining a second axis, the second axis being opposite the first axis on the crank arm;  
 a support member rotatably connected to the crank arm at the second axis;  
 a first link rotatably connected at opposing locations thereon to the frame and the lever arm;  
 a second link rotatably connected to the lever arm opposite the first link; and  
 a third link rotatably connected to the second link opposite the lever arm and slidably supported by the support member;  
 whereby the application of force by a user to the third link induces cyclic movement of the third link and rotates the crank arm to apply torque to the first axle, the cyclic movement being constrained by the second link and the support member so that at least a portion of the third link moves in a substantially elliptical path.  
   
     
     
         24 . The exercise machine of  claim 23 , wherein the cyclic movement of each third link is further constrained by a fourth link rotatably connected at opposing locations thereon to the frame and the third link.  
     
     
         25 . The exercise machine of  claim 23 , wherein the fourth link is rotatably connected to the third link at respective ends of the fourth link and the third link.  
     
     
         26 . The exercise machine of  claim 23 , wherein the fourth link has an upright handle opposite the rotatable connection with the third link for gripping by a hand of the user.  
     
     
         27 . The exercise machine of  claim 26 , wherein the fourth link is rotatably connected to an upright portion of the frame intermediate the handle and the rotatable connection with the third link.  
     
     
         28 . The exercise machine of  claim 23 , wherein the first axle is connected to a mechanism that resists rotation thereof, whereby the user's applied force must overcome the resistance of the mechanism to move the third link.  
     
     
         29 . The exercise machine of  claim 28 , wherein the first axle is connected to a wheel for rotation thereof, and the rotation-resisting mechanism applies friction to the wheel.  
     
     
         30 . The exercise machine of  claim 28 , wherein the rotation-resisting mechanism includes a gear assembly through which the torque applied to the first axle is at least partially consumed.  
     
     
         31 . The exercise machine of  claim 23 , wherein the crank arms of the drive systems are connected to the first axle so as to be orientated 180° apart from each other, whereby the respective third link portions move through substantially elliptical paths 180° out of sync.  
     
     
         32 . The exercise machine of  claim 23 , wherein the support member includes an axle fixed to the crank arm for movement therewith and a roller mounted for rotation about the axle.  
     
     
         33 . The exercise machine of  claim 23 , wherein the support member includes a roller rotatably connected to the crank arm for rotation about the second axis.  
     
     
         34 . The exercise machine of  claim 23 , wherein the lever arm is fixed to the support member for movement therewith.  
     
     
         35 . The exercise machine of  claim 23 , wherein the lever arm is rotatably connected to the support member for rotation relative to the support member.  
     
     
         36 . The exercise machine of  claim 23 , wherein the first link has first and second ends and is rotatably connected at its first and second ends to the lever arm and frame, respectively.  
     
     
         37 . The exercise machine of  claim 23 , wherein the second link has first and second ends and is rotatably connected at its first and second ends to the lever arm and the third link, respectively.  
     
     
         38 . The exercise machine of  claim 23 , wherein the lever arm has first and second ends and is rotatably connected at its first and second ends to the first link and second link, respectively.  
     
     
         39 . The exercise machine of  claim 23 , further comprising a foot pedal connected to each third link for engagement by a foot of a user so as to apply force to the third link, whereby the foot pedal moves in the substantially elliptical path.  
     
     
         40 . The exercise machine of  claim 39 , wherein the foot pedal is fixed to the third link for movement therewith.  
     
     
         41 . The exercise machine of  claim 40 , wherein the foot pedal is adjustably fixed to the third link so as to vary its position along the third link.  
     
     
         42 . The exercise machine of  claim 23 , wherein each drive system is configured such that the major axis of the substantially elliptical path lies in substantially horizontal plane and the minor axis of the substantially elliptical path lies in substantially vertical plane.  
     
     
         43 . The exercise machine of  claim 42 , wherein the major axis is at least four times the length of the minor axis.  
     
     
         44 . The exercise machine of  claim 43 , wherein the major axis is approximately six times the length of the minor axis.  
     
     
         45 . An exercise machine, comprising: 
 a load-bearing frame;    a first axle supported by the frame for rotation about a first axis;    a crank arm having first and second ends and being connected at its first end to the first axle such that the crank arm rotates about the first axis and applies torque to the first axle when rotated;    a second axle having a roller thereabout and being connected to the crank arm at the second end of the crank arm such that the second axle rotates in a circular pattern about the first axle when the crank arm is rotated;    a lever arm having first and second ends and being rotatably mounted about one of the second axles and the roller at a location on the lever arm intermediate its first and second ends;    a first link having first and second ends and being rotatably connected at its first end to the first end of the lever arm and rotatably connected at its second end to a fixed location on the frame such that the first link rotates about the fixed location;    a second link having first and second ends and being rotatably connected at its first end to the second end of the lever arm;    a third link having first and second ends and being rotatably connected at a position intermediate its first and second ends to the second end of the lever arm, the third link also engaging the roller for sliding movement thereover; and    whereby the application of force by a user to the third link induces rotation of the third link in a substantially elliptical path due to constraints on the motion of the third link imposed by second link, the fourth link, and the roller.    
     
     
         46 . The exercise machine of  claim 45 , further comprising a fourth link having first and second ends and being rotatably connected at its first end to the second end of the third link and rotatably connected at its second end to a elevated position on the frame such that the fourth link supports the third link and rotates about the elevated position.  
     
     
         47 . The exercise machine of  claim 45 , further comprising a pedal fixed to the third link for engagement by a foot of a user.  
     
     
         48 . The exercise machine of  claim 45 , wherein the first axle is connected to a resistance mechanism connected to the frame.  
     
     
         49 . The exercise machine of  claim 45 , wherein the second axle is fixed to the crank arm for movement therewith.  
     
     
         50 . The exercise machine of  claim 45 , wherein the second axle is rotatably connected to the crank arm for rotation about the second axis.