Patent Publication Number: US-6042512-A

Title: Variable lift cross trainer exercise apparatus

Description:
BACKGROUND OF THE INVENTION 
     1. Field 
     The present invention relates to a standup exercise apparatus that simulates walking and jogging with arm exercise. More particularly, the present invention relates to an exercise machine having separately supported pedals for the feet and arm exercise coordinated with the motion of the feet. The pedal lift is controlled separately and can be varied. 
     2. State of the Art 
     The benefits of regular exercise to improve overall health, appearance and longevity are well documented in the literature. For exercise enthusiasts the search continues for safe apparatus that provides full body exercise for maximum benefit in minimum time. 
     Recently, a new category of exercise equipment has appeared on the commercial market called elliptical cross trainers. These cross trainers guide the feet along a generally elliptical shaped curve to simulate the motions of jogging and climbing. Generally they are large exercise machines using long cranks to generate a long foot stride. There is a need for a more compact elliptical exercise machine capable of a similar long stride using a crank linkage. Further, there is a need to adjust lift of the elliptical motion to vary the amount of climb desired by the operator during operation. 
     Numerous combinations of levers and cranks to combine exercise for arms and feet can be found. Hex in U.S. Pat. No. 4,645,200 combines arm and foot levers for sit down exercise while Bull et al. in U.S. Pat. No. 4,940,233 combines arm and foot levers for standup exercise. Lucas et al. in U.S. Pat. No. 4,880,225 offer oscillating arm levers coupled to the foot crank by a connecting rod. Dalebout et al. in U.S. Pat. Nos. 4,971,316 and 5,000,444 also shows oscillating swing arms coupled to the foot crank by an offset second crank and connecting rod. Lom in U.S. Pat. No. 4,986,533 offers oscillating arms driven by a crank-slider coupled to a foot crank. 
     Recently, there has been an effort to improve the up and down motion of stair climbers by the addition of horizontal movements. Habing in U.S. Pat. Nos. 5,299,993 and 5,499,956 offers an articulated linkage controlled through cables by motor to move pedals through an ovate path. Both pedal pivots follow basically the same guidance path curve directed by a motor controller. Stearns in U.S. Pat. Nos. 5,290,211 and 5,299,993 shows a stair stepping exercise machine which incorporates horizontal movement using a combination of vertical parallelogram linkage and horizontal parallelogram linkage to guide the foot pedals. The parallelogram linkages serve to maintain the pedal at a constant angle relative to the floor during a pedal cycle. The pedal pivots move through similar undefined guide paths. 
     Standup cycling is described in various patents such as U.S. Pat. No. 3,563,541 (Sanquist) which uses weighted free pedals as load resistance and side to side twisting motion. Also U.S. Pat. Nos. 4,519,603 and 4,477,072 by DeCloux describe standup cycling with free pedals in a lift mode to simulate body lifting. 
     Standup pedal exercise is shown in U.S. Pat. No. 4,643,419 (Hyde) and by the DP Air Strider as previously sold by Diversified Products of Opelika, Ala. where pedal platforms move by dual crank motion but remain parallel to the floor. Knudsen in U.S. Pat. No. 5,433,680 shows an elliptical path generating mechanism with pedals having only one pivot allowing the pedal to rotate unconstrained about the pivot as in a bicycle crank. 
     Standup pedal exercise combined with arm levers attached to the pedals is shown in Kummerlin et al. German Pat. No. 2,919,494 and in Geschwender U.S. Pat. No. 4,786,050. Standup pedal exercise coupled with oscillating swing arms is shown in Miller U.S. Pat. Nos. 5,242,343 and 5,383,829 and in Eschenbach U.S. Pat. No. 5,423,729. All of these exercise machines use pedals having two pedal pivots which are guided by a first circular guide path curve generated by a crank which rotates through one full revolution during a pedal cycle and a second arc guide path curve generated by a rocker link or track. 
     Recently, numerous elliptical exercise machines have appeared in the patent literature. Rogers, Jr. in U.S. Pat. Nos. 5,527,246, 5,529,555, 5,540,637, 5,549,526, 5,573,480, 5,591,107, 5,593,371, 5,593,372, 5,595,553, 5,611,757, 5,637,058, 5,653,662 and 5,743,834 shows elliptical pedal motion by virtue of various reciprocating members and geared linkage systems. Miller in U.S. Pat. Nos. 5,518,473, 5,562,574, 5,611,756, 5,518,473, 5,562,574, 5,577,985, 5,755,642 and 5,788,609 also shows elliptical pedal motion using reciprocating members and various linkage mechanisms along with oscillating guide links with control links to determine pedal angles. Ryan et al. in U.S. Pat. No. 5,899,833 shows an elliptical cross trainer having a forward crank driving a pedal linkage underneath the operator. 
     Chang in U.S. Pat. No. 5,803,872 and Yu et al. in U.S. Pat. No. 5,800,315 show a pedal supported by a rocker link and driven with a pair of links located under the pedal pivotally connected to a crank. Maresh et al. in U.S. Pat. No. 5,792,026 show a foot support member supported by a rocker link and driven by a double crank mechanism. Lee in U.S. Pat. No. 5,779,598 and Chen in U.S. Pat. No. 5,823,914 show a pedal link driven by two separate cranks. Lin et al. in U.S. Pat. No. 5,769,760 offers elliptical foot and hand motion. Sands et al. U.S. Pat. No. 5,755,643 shows elliptical foot motion with folding front post. 
     Lee in U.S. Pat. No. 5,746,683 shows a foot support member supported on one end with a compound rocker wherein a slider and handle lever support the rocker. Kuo in U.S. Pat. No. 5,836,854 offers a linear foot support member connected on one end to a crank and guided along an arcuate curve under the pedal by a linkage on the other end. Wang et al. U.S. Pat. No. 5,830,112 shows a foot support member sliding on a pivot on one end and attached to a crank on the other that can fold. Chen U.S. Pat. No. 5,823,917 shows a foot support member driven by a crank on one end and supported by a stationary roller on the other. Chen U.S. Pat. No. 5,820,524 offers a slider crank mechanism having a pedal pivotally attached with a control link to articulate the pedal angle. 
     Chen U.S. Pat. Nos. 5,779,599 and 5,762,588 shows an elliptical pedal movement with a roller interface between the foot support member and crank. Chen in U.S. Pat. No. 5,759,136 shows a foot support member with a moving pedal for adjustable elliptical motion wherein a link from the pedal to the crank can be repositioned to change the pedal stroke length. Kuo U.S. Pat. No. 5,846,166 shows a foot support member guided on one end by a roller and driven on the other end by a four bar linkage. Stearns et al. in U.S. Pat. No. 5,848,954 offers a foot support member pivoted on one end with a lift crank on the other and a pedal moving on the foot support member to generate elliptical type foot motion. 
     Maresh et al. in U.S. Pat. No. 5,893,820 shows an adjustable lift elliptical cross trainer wherein the operator must interrupt exercise to relocate various pins to alter the pedal motion. Kuo U.S. Pat. No. 5,836,854 shows a foot support member driven by a crank and guided on one end by a linkage hanging from a &#34;Z&#34; shaped bar that may be adjusted. Whan-Tong et al. In U.S. Pat. No. 5,685,804 shows a foot support member driven by a simple crank having an adjustable ramp to vary pedal lift. Eschenbach in U.S. Pat. No. 5,916,064 shows handles for arm exercise coupled to a foot support member at one end with a connecting link. 
     There is a need for a pedal operated exercise machine that can be safely operated in the standup position whereby the arms and legs can be exercised with the feet moving through a generally elliptical path wherein pedal lift is variable during operation. 
     It is one objective of this invention to provide an elliptical pedal movement with a compound crank that reduces the steep pedal angle which can occur with a simple crank. Another object of this invention is to provide arm exercise that is coordinated with the pedal movement which allows pedal lift to be adjusted during operation. 
     SUMMARY OF THE INVENTION 
     The present invention relates to the kinematic motion control of pedals which simulate walking and jogging during operation. More particularly, apparatus is provided that offers variable intensity exercise through a leg operated cyclic motion in which the pedal supporting each foot is guided through successive positions during the motion cycle while a load resistance acts upon the mechanism. 
     The pedals are guided through an oblong or elongate curve motion while pedal angles are controlled to vary about the horizontal during the pedal cycle. Arm exercise is by arm handles coordinated with the foot pedals. 
     In the preferred embodiment, the apparatus includes a separate pedal for each foot, each pedal is supported by a foot support member which is pivotally attached on one end to a roller in contact with an adjustable guide pivoted to the framework. The foot support member is driven on the other end by a crank linkage consisting of a pair of crank arms, each having a crank roller rotatably connected to the crank arm for support of one end of the foot support member and an intermediate coupling link connecting the foot support member to an offset in the crank arm. The crank linkage reduces the pedal angles during upper portions of the elliptical motion because the crank end of the foot support member follows an oval instead of an arcuate curve. A crank completes one full revolution during a pedal cycle and is phased generally opposite the crank for the other foot support link through a bearing journal attached to the framework. 
     An actuator is pivoted to the framework and to the ramp to allow the angle the ramp makes with the floor to be adjusted during operation of the exercise machine. The actuator can be an electrically operated with linear movement or other arrangement intended to change the ramp angle during operation. 
     A pair of handles for arm exercise are attached to rocker links pivoted to the framework. The rocker links are coupled to the foot support members with connecting links that allow one end of the foot support member to be raised or lowered during operation. It is understood that the handles for arm exercise could be coupled to the foot support member by another means and remain within the scope of the present invention. 
     In an alternate embodiment, the crank rollers supporting the foot support member on the crank are replaced with control coupling links pivoted to the crank arms and to the foot support member. This crank linkage consisting of a pair of crank arms, each with control coupling link and intermediate coupling link produces an elliptical pedal motion similar to the preferred embodiment with less severe pedal angles. The remainder of apparatus is similar to the preferred embodiment. 
     Load resistance is applied to the crank in each embodiment by a pulley which drives a belt to a smaller pulley attached to an alternator and flywheel supported by the framework. In each embodiment, the flywheel must overcome the torque provided by the alternator. Adjustment of the alternator electronics provides variable intensity exercise for the operator. 
     In summary, this invention provides the operator with stable foot pedal support having adjustable foot lift during operation that simulate walking, jogging and climbing with very low joint impact and coordinated upper body exercise. Pedal angles are less severe during upper portions of the elliptical movement due to either embodiment of the crank linkage. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a right side elevation view of the preferred embodiment of an exercise machine with the ramp adjusted to a stride position constructed in accordance with the present invention; 
     FIG. 2 is the front view of the preferred embodiment shown in FIG. 1; 
     FIG. 3 is a right side elevation view of the preferred embodiment shown in FIG. 1 with the ramp adjusted to the climb position; 
     FIG. 4 is a right side elevation of the alternate embodiment. 
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring to the drawings in detail, pedals 14 and 16 are shown in FIGS. 1 and 2 in the lowest and highest positions of the preferred embodiment. Pedals 14 and 16 are attached to foot support members 10,12 which have rollers 34,36 rotatably attached to a second end at 29,31. The first end of foot support members 10,12 rest on crank rollers 62,64 which are rotatably attached to crank arms 18,20 at crank pins 22,25. 
     Crank arms 18,20 are joined inside bearing housing and frame member 57 protruding outwardly in generally opposing directions to comprise a crank. Further, crank arms 18,20 continue offset in length after pins 22,25 terminating with pivots 15,17. Intermediate coupling links 30,32 are pivoted to foot support members 10,12 at pivots 11,13 and to crank arms 18,20 at pivots 15,17. Crank arms 18,20, crank rollers 62,64 and intermediate links 30,32, form a pair of crank linkage which causes the first end of each foot support member to follow the oval path 6. The oval path 6 allows less severe pedal 14,16 angles during the upper portion of the pedal ellipse 5. 
     Rollers 34,36 are in rollable contact with guide 50. One end of guide 50 is attached to frame member 53 at pivot 43 and the other end is attached to actuator extension 52 at pivot 41. The actuator extension 52 is coupled to actuator 54 which is attached to frame member 51 at pivot 39. Actuator 54 will move actuator extension 52 up or down with linear movement by electric motor which raises or lowers guide 50. 
     Handles 46,48 for arm exercise are attached to rockers 42, 44 which are attached to frame member 63 at pivots 37. Connecting links 38,40 couple rockers 42,44 at pivots 33,35 to foot support members 10,12 at pivots 59,61. Connecting links 38,40 must be of sufficient length to allow the second ends of foot support members 10,12 to follow the guide 50 in all adjustments of guide 50. A length at least twice the height of the ellipse 5 is recommended. 
     Frame members 53 connect cross members 47,49 which contact the floor for support of the exercise machine. Frame member 63 attaches to frame member 51 which together with frame members 55 and 57 are attached to frame members 53. Load resistance is imposed upon cranks 18,20 by pulley 56 which drives flywheel/alternator 60 by belt 58 coupled to pulley 66. The flywheel/alternator 60 is supported by the frame member 55 at shaft 45. Other forms of load resistance may also be used. 
     Application of body weight on the pedals 14,16 causes the pedals 14,16 to follow elliptical curve 5 shown in FIG. 1 and together with force applied at the arm handles 46,48 cause the linkage to rotate the flywheel 60 for a gain in momentum. This flywheel 60 momentum will carry the linkage system through any dead center positions of the crank 18,20. The pedals 14,16 and arm handles 46,48 can be operated to drive the flywheel 60 in either direction of rotation. 
     FIG. 3 shows the preferred embodiment with the pedals 14,16 in the most forward and rearward positions. Guide 50 is in the uppermost position with actuator extension 52 nearly in contact with actuator 54. The pedal path 7 is a steeper ellipse having more pedal lift for a climbing motion. 
     An alternate embodiment is shown in FIG. 4 with pedals 14,16 in the lowermost and highest positions. Crank rollers 62,64 have been replaced with control coupling links 26,28 which are attached to crank arms 18,20 at pivots 23,25 and to foot support members 10,12 at pivots 19,21. Crank arms 18,20, intermediate coupling links 30,32 and control coupling links 26,28 form a pair of alternate crank linkage wherein pivots 19,21 follow oval path 4. Pivots 19,21 are located at the first end of foot support members 10,12 but could also be relocated elsewhere along foot support members 10,12 within the scope of this invention. 
     With the guide 50 in a low position, pedals 14,16 follow the pedal ellipse 2 which is similar to pedal ellipse 5 of the preferred embodiment. When guide 50 is raised, the pedals 14,16 follow pedal path 3 which is similar to pedal path 7 of the preferred embodiment. The remainder of the alternate embodiment is the same as the preferred embodiment. 
     In summary, the present invention has distinct advantages over prior art because the crank linkage provides attractive elliptical pedal motion without severe pedal angles. Further, the connecting links between the handle movement and the foot support member movement allow the guides to be adjusted over a large range to provide a significant range of pedal lift with arm exercise. 
     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the claims, rather than by foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.