hereinafter , embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains can realize the present invention . as those skilled in the art would realize , the described embodiments may be modified in various different ways , all without departing from the spirit or scope of the present invention . the exemplary embodiments of the present invention will be understood more fully from the detailed description given below and from the accompanying drawings of various embodiments of the invention , which , however , should not be taken to limit the invention to the specific embodiments , but are for explanation and understanding only . please refer to fig1 . as shown in part ( a ) of fig1 , the first embodiment of the present invention applies a four - bar linkage mechanism as the prototype . a main body 110 is served a fixed member , and a rotation mechanism 130 is disposed on a first pivot 1121 , a suspending rod 142 is pivotally connected to a suspending pivot 123 , and the active members of the rotation mechanism 130 and the suspending rod 142 are pivotally disposed at two ends of a tread rod 141 respectively . a pedal 145 is disposed on the tread rod 141 , and the suspending rod 142 and the tread rod 141 are pivotally connected on a movable pivot 1425 . by adjusting the rod length of at least one of the suspending rod 142 and the tread rod 141 , a relative position of the movable pivot 1425 changes . furthermore , the rotation mechanism 130 having two active members performs a circular action through the first pivot 1121 . in practice , the rotation mechanism 130 may be a crank or a flywheel mechanism . the suspending rod 142 is pivotally connected to the suspending pivot 123 to be swung back and forth . hence , it can be found that the four - bar linkage mechanism of the present embodiment is a crank set . as shown in part ( b ) of fig1 , when the rotation mechanism 130 is acting along the circle track , the pedal 145 disposed on the tread rod 141 acts along an elliptical closed track 180 to enable user performing the tread training . as to part ( c ) of fig1 , it shows that when the length of the linkage of the tread rod 141 is adjusted , the closed track 180 produces various included angles so as to further change the exercise type . the present embodiment shows that the type of the closed track 180 of the pedal 145 can be changed by adjusting the length of the tread rod 141 . the first embodiment applies a four - bar mechanism . it is known that the exercise type is able to be adequately adjusted by adjusting the relative position of the movable pivot 1425 . however , the limitations of the rods of the mechanism may interfere with the flexibility of the closed trace 180 and the natural gait tread . please refer to fig2 . the second embodiment further apples a linkage unit 160 having a triple - joint link 161 and a double - joint link 162 on the basis of the first embodiment . a stephenson six - bar linkage comprised of the linkage unit 160 , the rotation mechanism 130 and the guiding mechanism 140 facilitates the exercise track matching the natural gait tread . it can be found though fig2 that gait tread simulation fitness equipment 100 includes the main body 110 , the suspending side frame 120 that is disposed correspondingly , the rotation mechanism 130 and the guiding mechanism 140 . the main body 110 has a support frame 111 , and a central stand 112 disposed at a front end of the support frame 111 and having a first pivot 1121 . two suspending side frames 120 are respectively disposed at two sides of the main body 110 and each suspending side frame 120 may be disposed with a suspending pivot 123 . in practice , the suspending side frame 120 includes a vertical rod 121 , a horizontal rod 122 or a combination thereof . the suspending side frame 120 may be designed according to the actual requirements , supporting strength , and so on . for example , the vertical rod 121 applied in the present embodiment is able to be disposed vertically at the rear end of the support frame 111 , and the horizontal rod 122 may extend forwardly to connect to the central stand 112 . wherein , apart from sharing the loading of the support , the horizontal rod 122 is able to be designed according to actual requirements . two active members of the rotation mechanism 130 are disposed at two sides of the first pivot 1121 correspondingly by 180 °. two guiding mechanisms 140 are connected pivotally at two sides of the central stand respectively . each guiding mechanism 140 includes the tread rod 141 and the suspending rod 142 , the active member of the rotation mechanism 130 and the suspending rod 142 that are at the same side are connected by the tread rod 141 . one end of the suspending rod 142 is connected pivotally to the suspending pivot 123 , the other end of the suspending rod 142 and the tread rod 141 are connected pivotally to the movable pivot 1425 , and the pedal 145 is disposed on the tread rod 141 . when the pedal is treaded , the pedal 145 is actuated along the closed track 180 to enable the guiding mechanism being drawn back and forth . wherein adjusting at least one rod length of the suspending rod 142 and tread rod 141 is able to change a relative position of the movable pivot 1425 so as to facilitate the close track 180 matching the natural gait tread . in practice , the tread rod 141 further includes a stretching apparatus 1415 to adjust the relative position of the movable pivot 1425 . the stretching apparatus 1415 includes a single - stroke stretching apparatus , a multiple - stroke stretching apparatus or a linear actuator . similarly , the suspending rod 142 further includes a length adjustment apparatus to adjust the relative position of the suspending rod 142 . moreover , a position adjustment apparatus ( not shown ) may be disposed on the suspending rod 142 to adjust the relative position of the suspending pivot 123 or the relative position of the movable pivot 1425 . the position adjustment apparatus may be a gear wheel and rack set . please refer to fig3 . for the sake of further designing gait tread fitness equipment to match ergonomics and be capable of simulating the natural gait tread , the gait tread simulation fitness equipment disclosed in the present invention applies the theory of the topology mechanism to choose the optimal type of the kinematic chain which fits into the exercise track , so as to further facilitate the action track of the pedal to match the natural gait tread . the relative correlation among each linkage shown in part ( a ) of fig3 and the simulation shown in parts ( b ) and ( c ) of fig3 demonstrates the point which the exercise type can be changed easily and effectively by adjusting the length of the linkage or the position of the pivot . please refer to fig3 and fig4 to fig7 together . the schematic diagram and each diagram of the third embodiment demonstrate clearly the relative correlation among each rod of the third embodiment . the gait tread simulation fitness equipment 200 of the third embodiment includes the main body 210 , the suspending side frames 220 that are disposed correspondingly and the guiding six - bar linkages 230 . the main body 210 has a support frame 211 , and the central stand 212 disposed at a front end of the support frame 211 and having the first pivot 2121 and a second pivot 2122 . two suspending side frames 220 are respectively disposed at two sides of the main body 210 and each suspending side frame 220 is disposed with a suspending pivot 223 . in practice , the suspending side frame 220 includes a vertical rod 221 , a horizontal rod 222 or a combination thereof . the suspending side frame 220 may be designed according to the actual requirements , supporting strength , and so on . for example , the vertical rod 221 applied in the present embodiment is able to be disposed vertically at the rear end of the support frame 211 , and the horizontal rod 222 may extend forwardly to connect to the central stand 212 . wherein apart from sharing the loading of the support , the horizontal rod 222 is able to be designed according to actual requirements as well . two guiding six - bar linkages 230 are respectively disposed at two sides of the central stand 212 , each of the guiding six - bar linkages 230 is disposed at the first pivot 2121 and the suspending pivot 223 that are at the same side to form a constrained kinematic chain . the guiding six - bar linkage 230 includes a crank 231 , a swing rod 232 , a triple - joint link 233 , a tread rod 234 and a suspending rod 235 . wherein the crank 231 is connected pivotally to the first pivot 2121 and the swing rod 232 is connected pivotally to the second pivot 2122 and extends to form a handle . one end of the suspending rod 235 is connected pivotally to the suspending pivot 223 , and the other end of the suspending rod 235 and the tread rod 234 are connected pivotally to the movable pivot 2348 . the triple - joint link 233 is respectively connected to the crank 231 , the swing rod 232 and the tread rod 234 . the triple - joint link 233 and the suspending rod 235 are connected by the tread rod 234 , and the pedal 237 is disposed on the tread rod 234 to facilitate the pedal 237 actuating along the gait track 238 . to be more precise , when the crank 231 applies the first pivot 2121 as the circle center to rotate , acting the swing rod 232 and the tread rod 234 through the triple - joint link 233 while enabling the handle extended from the swing rod 232 being drawn back and forth is able to facilitate user &# 39 ; s hand to simulate the natural swing . the pedal 237 is disposed on the tread rod 234 , and through the correlation among each rod and the arrangement of the size , the gait track 238 is able to match the natural gait tread , such that each joint angle of the user &# 39 ; s lower limbs may be not affected due to the action track of the pedal 237 , and the risk of suffering from the sport injury is reduced greatly . furthermore , the first adjustment apparatus 2345 disposed on the tread rod 234 is able to change the length of the tread rod 234 or the position of the movable pivot 2348 , so as to enable the gait track 238 producing various lifting angles and the ranges , such that the objectives of adjusting the slope , the gait tread , and the kinematic chain are able to be achieved . in practice , a third adjustment apparatus ( not shown ) may be disposed on the suspending rod 235 . the action of the third adjustment apparatus is able to adjust the position of the suspending pivot 223 or the movable pivot 2348 . in practice , the third adjustment apparatus may be a gear wheel and rack set . please refer to fig8 which is a schematic diagram showing different aspect of the first adjustment apparatus . the first adjustment apparatus 2345 has various aspects . the positions of the movable pivot 2348 between the tread rod 234 and the suspending rod 235 which can be changed all belong to the applied aspect of the present invention . here are several common used aspects for explaining , but not limited thereto . the tread rod 234 shown in part ( a ) of fig8 is formed of an internal sleeve and an external sleeve which are sheathed and fixed with each other . two ends of the first adjustment apparatus 2345 are respectively disposed on the internal sleeve and the external sleeve , and when the first adjustment apparatus 2345 is actuated to change the relative position of the internal sleeve and the external sleeve , the length of the tread rod 234 changes . the first adjustment apparatus 2345 may be a single - stroke stretching apparatus , a multiple - stroke stretching apparatus or an actuator . another aspect shown in part ( b ) of fig8 demonstrates that the first adjustment apparatus 2345 has roller and guiding rail set . the suspending rod 235 is connected pivotally to the roller to thereby change the position of the roller to correspond to the relative position of the movable pivot 2348 , so as to change the exercise track . please refer to fig9 which is a schematic diagram of the second adjustment apparatus . it can be found according to the aforementioned points that the relative position of each rod is changed so that the exercise track is changed . for example , the suspending rod 235 may be designed as an aspect of sleeve sheath to cooperate with the second adjustment apparatus to change the length of the suspending rod 235 . the second adjustment apparatus 2355 includes various stretching apparatuses or linear actuators . the range of the action of the first adjustment apparatus 2345 or that of the second adjustment apparatus 2355 has to satisfy with the size limitation of the linkage mechanism so as to satisfy with the exercise track of the natural gait tread . applying the gait tread simulation fitness equipment 200 disclosed in the third embodiment to simulate and then analyze , it can be found that when the first adjustment apparatus 2345 is acting in a range of 0 - 40 cm , the gait tread range of the gait track 238 varies in a range of 45 cm - 65 cm , the lifting angle of the gait track 238 varies in a range of 0 °- 20 °, and the flat ratio of the long and short axis varies in a range of 8 : 1 - 3 : 1 . thus , it can be found through the preceding embodiments that the present invention is able to change different aspects of the exercise track such as the gait tread range , lifting angle , flat ratio , track smoothness , and so on to facilitate the exercise track matching the natural gait tread by adjusting the length of each rod to change the relative position of the pivot . by adding the adjustment apparatuses , the objective of adjusting the exercise track is able to be achieved . compared with the current various adjustment methods , the present invention indeed provides a relative inventive step and possesses flexibility of the adjustment method . moreover , by means of the simple arrangement of the linkage mechanism , the related cost can be saved so as to promote the industrial benefit . while the means of specific embodiments in present invention has been described by reference drawings , numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims . the modifications and variations should in a range limited by the specification of the present invention .
gait tread simulation fitness equipment is provided , which utilizes a multi - linkage mechanism disposed on a main body and a suspending side frame to make an action track of a pedal to match the natural gait tread well . in addition , the relative position of the movable pivot can be adjusted to obtain different exercise modes for training different muscle groups , so as to achieve the objective of exercise training .