Patent Publication Number: US-8979713-B2

Title: Pedal motion path adjustable elliptical trainer

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to elliptical machines and more particularly, to a pedal motion path adjustable elliptical trainer, which allows change of pedal motion paths. 
     2. Description of the Related Art 
     An Elliptical trainer is a stationary exercise machine used to simulate walking that moves along a smooth, elliptical path. Elliptical trainers offer a non-impact cardiovascular workout that can help you reach your health and fitness goals. The pedal motion paths of conventional elliptical trainers are constant, hence, the entire exercise will seem tedious, and will be unable to train all different muscles of the legs. 
     Taiwan Patent 1294294 discloses an elliptical trainer entitled “LEG-TRAINING ELLIPTICAL MACHINE”, which uses a screw rod of a slope control mechanism to control movement of a female screw member, causing the female screw member to bias a drag bar. When biasing the drag bar, the angle of a rail holder is changed relative to the floor to adjust the slope of the pedal motion paths. Further, Taiwan Patent M403355 discloses a lifting mechanism for an elliptical trainer, which uses a retractable rod of a linear actuator to adjust the angular position of a lift frame relative to the floor, thereby changing the pedal motion paths. The aforesaid two prior art patents allow control of the elevation of pedals to change the motion paths of sliding bars subject to different requirements from different users. However, the axis of rotation of each pedal is kept in parallel to the reference axis of the rotating mechanism assembly. When viewed from the top side, the left and right pedals can be simply biased in a front-rear direction. Thus, only a small part of the muscles of the legs can be trained during exercise, resulting in poor effects of exercise. In order to improve the drawbacks of the aforesaid two prior art designs, Taiwan Patent M407086 discloses an elliptical trainer, entitled “Improved structure of fitness elliptical machine”, which uses two sliding guide rails to control variation of the sliding motion path. The two sliding guide rails are formed of one single tubular member that is bent into a predetermined shape defining a parallel part and a splayed part. However, this design simply allows the machine to perform one specific motion model. If the user wishes to change the outward expansion angle, the user must purchase a different model of elliptical trainer or a different type of sliding rails, causing so much inconvenience. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a pedal motion path adjustable elliptical trainer which allows quick adjustment of the pedal motion paths, so that the user can pedal the pedals to move along respective front and back-biased motion paths and respective left and right-biased motion paths, training different muscles of the legs. 
     To achieve this object of the present invention, a pedal motion path adjustable elliptical trainer comprises a base frame, a rotating mechanism assembly, a lifting mechanism, a support link set, a control mechanism, and a sliding mechanism. The base frame is mounted on a support surface. The rotating mechanism assembly comprises two cranks coaxially pivoted to the base frame for performing a closed-path motion. The lifting mechanism comprises a rail holder, a support member, and two sliding rails. The rail holder is pivotally connected to the base frame, and biasable relative to the base frame. The rail holder comprises two first stop portions and two second stop portions. Each sliding rail comprises a pivot portion and a sliding portion. The pivot portion is pivoted to the support member. The sliding portion is coupled to the rail holder and movable between one respective first stop portion and one respective second stop portion. Each support link comprises a first end portion and a second end portion. The first end portion is pivoted to one respective crank. The second end portion is slidably coupled to one respective sliding rail. The linkage mechanism set comprises two handlebars and two links. The handlebars are respectively pivotally mounted at opposite left and right sides of the base frame. The links have the respective two opposite ends thereof respectively pivotally coupled between the handlebars and the second end portions of the support link set. The control mechanism is mounted between the base frame and the rail holder, and adapted to control the angle of deflection of the lifting mechanism. The sliding mechanism is pivotally coupled between the control mechanism and the rail holder for enabling the sliding portions of the sliding rails to move on the rail holder relative to each other. 
     Thus, subject to vertical swinging motion of the lifting mechanism and lateral displacement of the sliding mechanism, the pedal motion path adjustable elliptical trainer enables the user&#39;s legs to move along respective front and back-biased motion paths and respective left and right-biased motion paths, training different muscles of the legs. 
     Other advantages and features of the present invention will be fully understood by reference to the following specification in conjunction with the accompanying drawings, in which like reference signs denote like components of structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an oblique left top elevational view of a pedal motion path adjustable elliptical trainer in accordance with the present invention. 
         FIG. 2  is a left side view of the pedal motion path adjustable elliptical trainer in accordance with the present invention. 
         FIG. 3  is a top view of the pedal motion path adjustable elliptical trainer in accordance with the present invention. 
         FIG. 4  is a rear side view of the pedal motion path adjustable elliptical trainer in accordance with the present invention. 
         FIG. 5  is a side view, in an enlarged scale, of a part of the present invention, illustrating the status of the lifting mechanism before lift and the status of the sliding mechanism before lateral displacement. 
         FIG. 6  is a top view, in an enlarged scale, of a part of the present invention, illustrating the status of the lifting mechanism before lift and the status of the sliding mechanism before lateral displacement. 
         FIG. 7  corresponds to  FIG. 5 , illustrating the lifting mechanism lifted and the sliding mechanism displaced laterally. 
         FIG. 8  corresponds to  FIG. 6 , illustrating the lifting mechanism lifted and the sliding mechanism displaced laterally. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1-4 , an elliptical trainer  10  in accordance with the present invention is shown comprising a base frame  20 , a rotating mechanism assembly  30 , a lifting mechanism  40 , a support link set  50 , a linkage mechanism set  60 , a control mechanism  70 , a sliding mechanism  80 , and a linking-up member  90 . 
     The base frame  20  is mounted at a support surface G. 
     The rotating mechanism assembly  30  comprises two opposing cranks  32  coaxially pivoted to the base frame  20  to perform a closed-path motion. 
     The lifting mechanism  40  comprises a rail holder  42 , two sliding rails  44 , a support member  46 , and a bracket  48 . The rail holder  42  is pivotally connected to the base frame  20  and biasable relative to the base frame  20 , comprising two first stop portions  422  and two second stop portions  424 . Each sliding rail  44  comprises a pivot portion  442  and a sliding portion  444 . The pivot portion  442  is pivoted to the support member  46 . The sliding portion  444  is movable on the rail holder  42  between one respective first stop portion  422  and one respective second stop portion  424 . The bracket  48  comprises a frame rod  482 , a wheel axle  484 , and two rollers  486 . The frame rod  482  is pivotally connected to the support member  46  of the lifting mechanism  40  and the front end of the linking-up member  90 . The wheel axle  484  is connected to the bottom end of the frame rod  482 . The two rollers  486  are rotatably mounted at the two opposite ends of the wheel axle  484  for stopping against the support surface G. 
     The support link set  50  comprises two opposing first end portions  52  and two second end portions  54 . Each of the two first end portions  52  is pivoted to one respective crank  32 . Each of the two second end portions  54  is mounted with a pulley block  542  that is supported on one respective sliding rail  44 , enabling the second end portion  54  to move along the respective sliding rail  44 . The support link set  50  further comprises two pedals  544  respectively arranged at the top side of the second end portion  54  and biasable on the longitudinal axis thereof in a left-right direction. 
     The linkage mechanism set  60  comprises two handlebars  62  and two links  64 . The two handlebars  62  are respectively disposed at left and right sides relative to the base frame  20 . The links  64  are respectively pivotally connected between the handlebars  62  and the second end portions  54  of the support link set  50 . 
     The control mechanism  70  is mounted between the base frame  20  and the rail holder  42 , comprising a motor  72  and a drive rod  74 . The motor  72  is mounted at the support member  46  of the lifting mechanism  40 . The drive rod  74  is mounted at the rear side of the motor  72 , and movable forwards and backwards relative to the motor  72 . 
     The sliding mechanism  80  is pivotally mounted between the control mechanism  70  and the rail holder  42 , comprising a locating block  82 , a slide  84  and two connection members  86 . The locating block  82  is fixedly mounted at the support member  46  of the lifting mechanism  40 . The slide  84  is affixed to the drive rod  74  and movably supported on the locating block  82 . The connection members  86  have the front ends thereof pivotally connected to the slide  84 , and the rear ends thereof slidably coupled to the rail holder  42  and movable relative to each other for moving the sliding portions  444  of the sliding rails  44  on the rail holder  42  relative to each other. 
     The linking-up member  90  has the two opposite ends thereof respectively pivotally connected to the support member  46  of the lifting mechanism  40  and the slide  84  of the sliding mechanism  80 , and adapted to bias the support member  46  up and down relative to the support surface G subject to change of the length of the drive rod  74  and to simultaneously drive the sliding rails  44  to turn about the axes of the respective pivot portions  442  in performing a scissor action. 
     Referring to  FIGS. 5 and 8 , the drive rod  74  comprises a screw rod  742  and a socket nut  744 . The screw rod  742  has its one end connected to the motor  72  so that the motor  72  can rotate the screw rod  742 . The socket nut  744  is threaded onto the screw rod  742  and pivotally coupled with the slide  84 , and can be driven by screw rod  742  to move axially along the screw rod  742  and to further carry the sliding mechanism  80 . Thus, when the user wishes to change the motion path of the pedals  544 , the user can start the motor  72  to rotate the screw rod  742  of the drive rod  74 . At this time, the socket nut  744  of the drive rod  74  will be driven by the screw rod  74  to move the slide  84  backwards, causing the connection members  86  to be biased relative to the slide  84  toward the respective second stop portions  424 . Further, subject to the arrangement that the linking-up member  90  has the two opposite ends thereof respectively pivotally connected to the support member  46  of the lifting mechanism  40  and the slide  84  of the sliding mechanism  80  and the bracket  48  is pivotally connected to the support member  46  of the lifting mechanism  40 , moving the slide  84  backwards can drive the support member  46  to make a relative motion, causing the bracket  48  to move with the rollers  486  along the support surface G stably backwards. During movement of the bracket  48  along the support surface G, the lifting mechanism  40  will be forced to turn the support member  46  about the axis of the rail holder  42  upwardly to a predetermined angle relative to the support surface G. Thus, the pedals  544  are lifted with the support member  46  of the lifting mechanism  40  to change their angle of inclination. At this time, subject to the arrangement that the pivot portions  442  of the sliding rails  44  of the lifting mechanism  40  are pivoted to the support member  46  and the connection members  86  of the sliding mechanism  80  have the respective front ends thereof respectively pivotally connected to the slide  84  and the respective rear ends thereof respectively slidably coupled to the rail holder  42  and respectively pivotally coupled to the sliding portions  444  of the sliding rails  44 , the sliding rails  44  will be turned about the axes of the respective pivot portions  442 , causing the sliding portions  444  to be moved from the respective first stop portions  422  of the rail holder  42  toward the respective second stop portions  424 . Thus, the pedals  544  can be pedaled to move along respective front and back-biased motion paths and respective left and right-biased motion paths, training different muscles of the user&#39;s legs. 
     Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.