Patent Publication Number: US-7591761-B1

Title: Walking/jogging exercise machine with articulated cam follower arrangement

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to walking and jogging conditioning devices and, more particularly, pertains to standup exercise equipment wherein a user&#39;s feet travel through a curved path of travel to produce a more natural motion of walking or jogging. 
     BACKGROUND OF THE INVENTION 
     Recognizing the benefits of exercise contrasted with the various constraints of time and space limiting exercisers in using their lower and upper body muscles, various walking/jogging machines have been designed to provide for physical development and aerobic exercise. It is generally desirable to create a machine that will allow a user to walk or jog without the impact on the user&#39;s joints that occur while running on the ground or on a treadmill. There are a number of elliptical machines on the market today which achieve this result, but force the users into an unnatural motion. 
     In the inventor&#39;s previous U.S. Pat. No. 6,758,790, issued Jul. 6, 2004, a walking/jogging exercise machine includes a frame supported upon a generally horizontally extending floor, and a main driveshaft mounted for rotation on the frame. A pair of cams is mounted for rotation on the driveshaft, and a pair of first track assemblies are affixed to the frame. A pair of second track assemblies is rotatably attached to the frame and includes brackets having first rollers which ride upon the peripheries of the cams. A pair of non-aligned, foot assemblies are mounted for sliding movement on the first and second track assemblies. A linkage arrangement is provided between the driveshaft and the foot assemblies for transferring the movement of the foot assemblies to the cams so as to produce a change in the angle of a user&#39;s ankle which will result in a natural walking/jogging motion. 
     While the exercise machine disclosed in the &#39;790 patent has performed generally satisfactorily, it is felt that the walking/jogging machine can be restructured to provide a more enhanced stepping and striding motion. In particular, it is desirable to improve upon the increase in bending of a user&#39;s knees concurrent with the change in the user&#39;s heel-to-toe movement. 
     SUMMARY OF THE INVENTION 
     It is a general object of the present invention to provide an exercising machine which enables an individual to exercise lower and upper body muscles over a range of motion. 
     It is also an object of the present invention to provide an exercise machine which permits one&#39;s feet to move along a smooth path during exercise. 
     It is a further object of the present invention to provide an exercise machine which utilizes a driving and cam arrangement and a linkage system to produce a low impact, naturally ambulatory motion. 
     It is an additional object of the present invention to provide a walking/jogging exercise machine having an articulated cam follower arrangement which will result in an improved knee bending motion. 
     In one aspect of the invention, a walking/jogging machine includes a machine frame supported on a generally horizontally extending floor. A shaft is mounted for rotation on the machine frame, and a pair of cams is mounted for rotation on the shaft. A pair of movable track assemblies is provided with each having rear portions with rear ends pivotally connected to the machine frame, and front portions with movable front ends. A pair of articulated cam follower assemblies extends between the machine frame and the front ends of the track assembly front portions, and include cam rollers operably engaged upon peripheries of the cams. The cam follower assemblies move in response to rotation of the cams. A pair of foot assemblies is mounted for sliding movement on the track assemblies. A linkage arrangement is provided between the cams and the foot assemblies for transferring movement of the foot assemblies to the cams such that the articulated cam follower assemblies enable a leveraged range of up and down movement of the track assemblies to produce an increase in a bending of the user&#39;s knees resulting in a natural stepping motion. 
     The machine frame includes an elongated base member engaged with the floor, a first upwardly rising support member joined to the base member, a second upwardly rising support member spaced rearwardly of the first support member and affixed to the base member, a support brace interconnecting the first and second support members, and a transverse support member joined to the first support member and the base and engaged with the floor. A circular drive pulley is mounted for rotation on the shaft between the cams. A brake assembly is attached to the machine frame beneath the cams and is entrained with the drive pulley by a drive belt. The machine frame carries an electronic controller operably connected to the brake assembly for providing resistance to the drive pulley. The rear portions of the track assemblies extend horizontally and the front portions of the track assemblies extend at an angle relative to the rear portion and are formed integrally therewith. Each front portion of the track assembly extends at an acute angle relative to a horizontal plane of an upper surface of each rear portion. The foot assemblies include support braces having rearward ends which ride back and forth on the rear portions of the track assemblies. The foot assemblies include support braces having forward ends which ride back and forth on the front portions of the track assemblies. 
     The articulated cam follower assemblies include roller frames for holding and rotatably mounting the cam rollers thereon, and cam follower links pivotally connected to the roller frames. Each roller frame has a front end pivotally connected to the machine frame, and a back end pivotally secured to an upper end of each cam follower link. A lower end of each cam follower link is pivotally attached to the front end of each track assembly. The linkage arrangement includes a pair of swing arms pivotally attached to the machine frame, a pair of forward connecting links having forward ends pivotally connected to the cams and rearward ends connected to the swing arms, and a pair of rearward connecting links having forward ends pivotally connected to the swing arms and rearward ends pivotally connected to the foot assemblies. In the exercise machine, the shaft defines a first horizontal pivot axis. The cam follower assemblies are pivotally connected about a second horizontal pivot axis. The rear ends of the track assemblies are pivotally attached about a third horizontal pivot axis. The linkage arrangement is pivotally secured about a fourth horizontal pivot axis. 
     The invention further contemplates a method of walking/jogging in an exercise machine. The method includes the steps of providing a machine frame supported on a generally horizontal floor; mounting a shaft for rotation on the frame; mounting a pair of cams for rotation on the shaft; movably mounting a pair of track assemblies to the frame; pivotally mounting a pair of articulated cam follower assemblies between the frame and the track assemblies such that the cam follower assemblies include cam rollers that operably engage peripheries of the cam; providing a pair of foot assemblies for sliding movement on the track assemblies; and providing a linkage arrangement between the cams and the foot assemblies for transferring movement of the foot assemblies to the cams such that the articulated cam follower assemblies enable a leverage range of up and down movement of the track assemblies to produce an increase in bending of a user&#39;s knees resulting in a natural stepping motion. 
     Various other objects, features and advantages of the invention will be made apparatus from the following description taken together with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings illustrate the best mode presently contemplated in carrying out the invention. 
       In the drawings and the specification, the terms front, rear, right and left are used herein from the perspective of a user facing the exercise machine. 
         FIG. 1  is a front perspective view of a low impact walking/jogging machine constructed in accordance with the invention; 
         FIG. 2  is a rear perspective view of the exercise machine of  FIG. 1  taken from a left side; 
         FIG. 3  is a rear perspective view of the exercise machine of  FIG. 1  taken from a right side; 
         FIG. 4  is a left side elevational view of  FIG. 1 ; 
         FIG. 5  is a right side elevational view of  FIG. 3 ; 
         FIG. 6  is an exploded view of the exercise machine in  FIG. 1  with certain parts being removed for clarity; and 
         FIGS. 7   a - 7   d  are simplified diagrams showing the sequence of motion of the exercise machine. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is advantageously directed to an improved exercise machine which primarily moves a user&#39;s feet and legs through a natural range of striding and stepping motion associated with walking, jogging and running. 
     General Overview 
     Referring now to the drawings,  FIGS. 1-6  illustrate the structure of an exercise machine  10  constructed in accordance with the invention. 
     The exercise machine  10  is designed with a left side and right side which are substantially identical. The left side and the right side are staggered in such a manner such that when the user&#39;s left foot is at an extreme rear extent of travel, the right foot is at an extreme forward extent of travel. This arrangement employs a machine frame  12  for mounting a cam assembly  14  generally comprised of a pair of right hand and left hand cams  16 , 18 , a circular drive pulley  20  and an internally threaded connecting shaft  22  as best seen in  FIGS. 2 and 6 . The right hand cam  16  and the drive pulley  20  are welded to the connecting shaft  22  such that the right hand cam  16  is elliptically fixed relative to the drive pulley  20  with the shaft  22  passing through the center of the drive pulley  20 . The shaft  22  passes through a set of bearings  24  and a pivot tube  26  provided on the frame  12 , and further passes through an offset hole formed in the left hand cam  18 . The left hand cam  18  is joined to the shaft  22  with a bolt  28  and a washer  30  so that the cams  16 , 18  and drive pulley  20  are rotatably mounted together relative to the frame  12 . The left hand cam  18  and the shaft  22  have a keyway  32  ( FIG. 6 ) machined into them into which a key  34  is placed to lock the left hand cam  18  into a fixed position with the right hand cam  16  so that the high points of the cams  16 , 18  are located 180° opposite each other. Each of the cams  16 , 18  has a tubular connecting shaft  36  extending outwardly therefrom. The drive pulley  20  is connected with a drive belt  38  to a generator/brake assembly  40  mounted to the frame  12 . Belt tensioning structure  39  ( FIG. 3 ) is provided to prevent slippage of the drive belt  38 . The brake assembly  40  is operably connected by wires or the like to an electronic controller  42  positioned upwardly on the frame  12 . This braking system provides resistance to rotation of the drive pulley  20  and other interconnected components to be described to vary the difficulty of the exercise. It should be understood that other resistance devices, such as a simple brake, could be used. 
     The machine  10  has a pair of movable track assemblies  44  for slidably receiving a pair of foot assemblies  46  which move in a back and forth motion relative to the frame  12  and each other. A pair of articulated cam follower assemblies  48  extend between the frame  12  and front ends of the track assemblies  44 . The cam follower assemblies  48  are provided with cam rollers  50  which ride upon outer peripheries of the cams  16 , 18  during operation of the machine  10 . A movable linkage arrangement  52  is provided between the cams  16 , 18  and the foot assemblies  46  for transferring movement from the foot assemblies  46  to the cams  16 , 18 . As will be appreciated below, the cooperation of the above-described major components results in a substantially enhanced, natural stepping and striding motion. 
     Component Details 
     The exercise machine frame  12  rests upon a floor  54 , and includes a tubular base member  56  running from a front end to a rear end. The rear end is provided with a cylindrical endpiece  58  having a pivot shaft  60  that projects laterally from each side of the endpiece  58 . A first upwardly rising support member  62  is joined to the front end of the base member  56 , and has a rearward bent neck  64  for supporting the electronic controller  42 . The first support member  62  also carries a cylindrical support stub  66  having a pivot shaft  68  extending laterally from opposite sides for pivotally supporting the cam follower assemblies  48  from the frame  12 . A second upwardly rising support member  70  is fixed to the base member  56  rearwardly of the first support member  62 . The second support member  70  has a cross tube  72  at its upper end having a pivot shaft  74  projecting from opposite ends. The cross tube  72  carries a pair of spaced apart fixed handgrips  76  which may be grasped by a user during operation, if desired. As seen best in  FIG. 6 , the bottom end of the second support member  70  includes an attachment bracket  78  for mounting the brake assembly  40 . A support brace  80  interconnects the first and second support members  62 , 70 , and is provided with a pivot tube  26  holding the bearings  24  through which the connecting shaft  22  passes. A transverse support member  82  is fixed to the front end of the base member  56  and the bottom end of the first support member  62  for engagement with the floor  54 , and provides lateral stability for the machine  10 . Opposite ends of the transverse support member  82  have mounting plates  84  carrying wheels  86  which enable moving of the machine  10  when it is lifted from its rear end. 
     Each movable track assembly  44  includes a horizontally extending rear portion  88  fixedly joined to an angled front portion  90 . More particularly, each front portion  90  extends at an acute angle relative to a horizontal plane of an upper surface of each rear portion  88 . Each rear portion  88  has a rear end provided with a set of pillow block bearings  92  that are attached to a bottom end using fasteners  94  ( FIG. 6 ). The pillow block bearings  92  are pivotally attached to the pivot shaft  60  at the rear end of the base member  56  so that the rear ends of the track assemblies  44  pivot on the rear of the frame  12 . Each rear portion  88  has a pair of spaced apart tracks  96  on a flat base plate  98 . The front portions  90  form single tracks and have front ends which are pivotally connected to the cam follower assemblies  48 . The rear portions  88  support back portions of the foot assemblies  46 , while the front portions  90  support forward portions of the foot assemblies  46 . Each track assembly  44  is designed to pivot as a unit. 
     As seen best in  FIG. 6 , each of the foot assemblies  46  includes a walled foot pedal  100  for positioning the user&#39;s foot thereon. The foot pedal  100  is mounted on a support base  102  having a pair of spaced apart plates  104 . Pillow block bearings  106  are attached by bolts  107  to lateral surfaces of the support plates  104 . Rearward ends of the plates  104  have laterally extending pins  108  for holding a pair of rotatable rear wheels  110 , bearings  112  and nuts  114 . Forward extended ends of the plates  104  retain a single rotatable front wheel  116  attached through bearings  118  and spacer bushings  120  with a bolt  122  into a nut  124 . The rear wheels  110  are rollably engaged with the tracks  96  on the rear portions  88  of the movable track assemblies  44 . The single front wheels  116  are rollably engaged with the single tracks  126  formed by the front portions  90  of the movable track assemblies  44 . 
     Each of the articulated cam follower assemblies  48  has a roller frame  128  having a cylindrical cuff  130  at a forward end, and a mounting hole at a rearward end thereof. Each cam roller  50  that rides on the eccentric periphery of its cam  16 , 18  is rotatably mounted within the roller frame  128  on bearings  132  and is retained by a bolt  134  held by a nut  136 . The forward end of each roller frame  128  is pivotally mounted on the pivot shaft  68  of machine frame first support member  62  via pop-in bearings  138  inserted in the cuff  130 . Each articulated cam follower assembly  48  further includes a straight cam follower link  140  having an upper end pivotally attached by a pin  142  and nut  144  to the rearward end of the cam roller frame  128 . Each link  140  has a lower end pivotally connected by a pin  146  and a nut  148  to the front portion  90  of one of the track assemblies  44 . As a feature of the present invention, it will be appreciated that the articulated cam follower assemblies  48  permit an enhanced up and down motion of the track assemblies  44  which improves the natural stepping motion of the machine  10 . 
     The linkage arrangement  52  has a pair of swing arms  150  pivotally attached to the machine frame  10 . A pair of forward connecting links  152  has forward ends pivotally connected to the cams  16 , 18 , and the rearward ends pivotally joined to the swing arms  150 . A pair of rearward connecting links  154  has forward ends pivotally connected to the swing arms  150 , and rearward ends pivotally to the foot assemblies  46 . 
     More specifically, each swing arm  150  is formed with an upwardly extending handle  156  and includes a pivoting tubular cuff  158  holding pop-in bearings  160  which surround pivot shaft  74  on the second support member  70 . A bolt  162  passes through a first horizontal tube  164  in the swing arm  150  as well as through pop-in bearings  166  provided at a rearward end of each forward connecting link  152 . The inner end of the bolts  162  receives a nut  168  to hold the forward connecting link  152  and swing arm  150  together. A further bolt  170  passes through pop-in bearings  172  at the forward end of the forward connecting link  152  and the tubular connecting shaft  36  projecting from cams  16 , 18 . An inner end of the bolt  170  is threaded into a nut  174  to maintain the pivotal connection of the front of the forward connecting link  152  to the cams  16 , 18 . Another bolt  176  passes through a second lower tube  178  in the swing arm  150  as well as through pop-in bearings  180  provided at a forward end of the rearward connecting link  154 . The inner end of the bolt  176  is threaded into a nut  182  to pivotally hold the rearward connecting link  154  and the bottom of swing member  150  together. The rearward end of each rearward connecting link  154  has a rod  184  which is pivotally connected to one of the pillow block bearings  106  attached to one of the foot assemblies  46 . 
     It can be seen that the cams  16 , 18  are pivotally mounted about a first horizontal pivot axis defined by the connecting shaft  22 . The cam follower assemblies  48  are pivotally mounted about a second horizontal pivot axis defined by the pivot shaft  68 . The track assemblies  46  are pivotally mounted about a third horizontal pivot axis defined by the pivot shaft  60 . The swing arms  50  are pivotally mounted about a fourth horizontal pivot axis defined by the pivot shaft  74 . 
     Operation 
       FIGS. 7   a - 7   b  illustrate the sequence of movement in the operation of the exercise machine  10  as viewed from the left side thereof. In  FIG. 7   a , the left foot assembly  46  is moved forward from its rearwardmost position on track assembly  44  causing the rearward connecting link  154  to propel the swing arm  150  forwardly. This motion is translated through the forward connecting link  152  to result in rotation of the cam  18 . As the cam roller  50  rises along the irregular moving periphery of the cam  18 , the articulated cam follower assembly  48  initiates a downward motion at the front of the moving track assembly  44 . 
     Downward motion of the track assembly  44  continues as the foot assembly  46  moves to a forwardmost toe-up position shown in  FIG. 7   b . At this point, further movement of the foot assembly  46  causes the swing arm  150  to move rearwardly. The combined forward movement of the foot assembly  46  on the pivoting track assembly  44  has the effect of raising the user&#39;s foot and changing the angle of the user&#39;s ankle as happens while striding and stepping forward. 
       FIG. 7   c  shows a foot assembly  46  reversing in a rearward direction causing further downward motion at the front of the track assembly  44  and forward movement of the swing arm  150  as the ankle position of the user continues to change. In  FIG. 7   d , the foot assembly  46  has been moved to its rearwardmost position, causing the swing arm  150  to move further forwardly. Here, the cam follower assembly  48 , reacting to the repositioning of the cam  18 , begins moving upward. This causes raising of the front of the track assembly  44  as a user&#39;s foot assumes a toe-down position. As the left side foot assembly  46  is driven forward causing the left hand cam  18  to rotate, the right hand assembly  44  is driven rearwardly causing the right side cam  16  to rotate so as to create a natural walking/jogging motion. 
     It should be fully appreciated that during the entire sequence of motion, the articulated cam follower assemblies  48  enable a leveraged range of an alternating up and down motion of the track assemblies  44 . This produces an increase in flexure or bending of the user&#39;s knees, which together with the heel-to-toe movement of the user&#39;s feet, results in an enhanced natural stepping and striding motion and effective lower body exercise. Upper body exercise is simultaneously obtained by moving the swing arms  150  back and forth. Alternatively, the user may choose to hold onto the fixed hand grips  76 , if only lower body exercise is desired. 
     During motion of the machine  10 , the drive pulley  20  will rotate. Because the drive pulley  20  is connected by the drive belt  38  to the brake assembly  40  and the electronic controller  42 , a varying level of resistance is provided to vary the difficulty of the exercise. The electronic controller  42  is preferably battery-powered and designed to provide a set of various walking or jogging programs. The controller  42  can also be variously programmed to reflect distance traveled, time elapsed, calories burned and other desirable parameters. 
     Various alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention.