Method for adjusting the traveling path of a tread-training device

Abstract

A method for adjusting the traveling path of a tread-training device is disclosed. The tread-training device has a seat which is connected with a curved handle, and another end thereof is installed with a left crank and a right crank. Ends of the left crank and the right crank are pivotally connected to a left treading rod and a right treading rod; and another ends of the treading rods are pivotally to ends portions of a left driving rod and a right treading rod. The axial rod moves along a cambered path so that the orientations of the driving rods are altered or the highest points and lowest points of the pivotal points of the treading rods are altered so that tracks of moving path of the treading rods are altered. Therefore, the tread-training device is adjusted so that the user moves as along an upward path, a flat path and a downward path.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the invention

[0002] The present invention relates to adjustment of a tread-training device, and especially to method for adjusting the traveling path of a tread-training device.

[0003] 2. Description of the Relative Art

[0004] A prior exercise device to simulated various types of stepping motions is disclosed in U.S. Pat. No. 6,146,313. In the present invention, the following elements are disclosed. A frame has a pivot axis defined thereon. The frame is configured to be supported on a floor. A first and second foot links. Each foot link includes a first end and a second end. A foot support serves for receiving the user's feet. The foot support is supported by the first and second foot links and has a heel supporting section and toe supporting section. A coupling system is associated with the first end of each foot link for coupling the first end of each foot link to the pivot axis so that the first end of each foot link travels in a closed path relative to the pivot axis. A guide associated with the frame and operative to engage and direct the second ends of the foot links along preselected receprocating paths as the first ends of the respective foot links travel along their paths of traveling, so that when the exercise device is in use and when the second end of the foot links travels forwards from a rearmost position, the heel supporting section of the foot support rising relative to the toe supporting section of the foot support so that the heel position of the user's foot initially rises at a faster rate than a toe position thereof and when the second end of the foot link travels rearwardly from a foremost end, the heel supporting position of the foot support lowering relative to the toe supporting, section of the foot support so that the heel portion of the user's foot initially lowers at a faster rate than the toe portion. A elevation system serves for selectively and automatically changing at least one of the elevation and angular orientation of the guide relative to the frame so as to alter the path travels by the second ends of the first and second links, and to alter the nominal relative orientation of the heel supporting section of the foot supporting relative to the toe supporting section of the foot support.

[0005] From FIGS. 1 to 10 of the prior art, the first and second foot links of the exercise device have ends resisting against a tilt guide. Thereby, each foot link can move along a reciprocating path. Therefore, when the first and second foot links move along elliptical paths, a larger friction force generates in the contact surface between the first and second foot link and the guide. As a result, the resisting force will increase as the foot link moves reciprocally so that the operation of relative parts will not be smooth. Furthermore, it is possible that the parts will be buckled and become motionless.

[0006] Moreover, elevation system serves to provide a function of adjusting the elevation of the guide relative to the floor for altering the moving path of the foot supports. However, the variation of the moving path is just a little. Even the guide is adjusted to a largest inclined angle or a smallest inclined angle, a line from the highest supporting point to the lowest supporting point of the first and second foot supports are sustained in a positive angle (about from +10.degree. to +45.degree.). Therefore, the moving path just alters a little. Therefore, the above way is not a preferred way. Referring to FIGS. 1 to 4, when the moving paths are illustrated, wherein the guide 100 has a 10.degree. (referring to FIG. 1), 20.degree. (referring to FIG. 2), 30.degree. (referring to FIG. 3), and 40.degree. (referring to FIG. 4) with respect to the horizontal surface. It is apparent that the variations of the elliptical paths are only a little.

SUMMARY OF THE INVENTION

[0007] Accordingly, the primary object of the present invention is to provide a method for adjusting the traveling path of a tread-training device; wherein the tread-training device has a seat. One end of the seat of the tread-training device is connected with a curved handle, and another end thereof is installed with a left crank and a right crank which are coaxially arranged. Ends of the left crank and the right crank are pivotally connected to a left treading rod and a right treading rod; and another ends of the left treading rod and right treading rod are pivotally connected to end portions of a left driving rod and a right treading rod which are capable of swinging forwards and rearwards freely. The axial rod moves along a cambered path so that the orientations of the left driving rod and right driving rod are altered or a highest point and a lowest point of a pivotal point of the left treading rod and the left driving rod and a highest point and a lowest point of a pivotal point of the right treading rod and the right driving rod are altered so that tracks of moving path of the treading rods are altered. Therefore, the tread-training device is adjusted so that the user moves as along an upward path, a flat path and a downward path.

[0008] Another object of the present invention is to provide a method for adjusting the traveling path of a tread-training device, wherein a vertical line from a center of an axis of a round are formed by the path is used as a reference line of zero degree, then the axial rod is adjusted to and positioned in a positive or a negative angles with respect to the vertical line.

[0009] Another object of the present invention is to provide a method for adjusting the traveling path of a tread-training device, wherein a method for adjusting the traveling path of a tread-training device. The tread-training device has a seat. One end of the seat is connected with a supporting rod of a curved handle; and another end thereof is installed with a left crank and a right crank which are coaxially arranged; ends of the left crank and the right crank are pivotally connected to a left treading rod and a right treading rod. The supporting rod has a positioning frame having a cambered hole; a lower end of the cambered hole has a plurality of grooves which are spaced arranged for positioning the axial rod of the left driving rod and right driving rod. Two ends of the axial rod are pivotally connected with a left driving rod and a right driving rod. Thereby, when the user treads upon pedals of the left treading rod and right treading rod, a flexible and harmonic elliptical track is generated. Adjusting the axial rod connecting the left driving rod and right driving rod to different groove at a bottom end of the cambered hole. The angle relation of the line from the highest point to the lowest point of pivotal point of the left treading rod and the left driving rod and the angle relation of the line from the highest point to the lowest point of pivotal point of the right treading rod and the right driving rod are altered. Therefore, the slope of the elliptic path is altered, and the tread-training device is adjusted so that the user may move as along an upward path, a flat path and a downward path.

[0010] Another object of the present invention is to provide a predetermined position of the sleeve installed with a penetrating hole; a positioning pin is inserted into the penetrating hole; an adjusting rod is inserted into the sleeve; a bank of oblong holes are formed on the middle section of the adjusting rod; two lateral sides of the oblong holes are formed with cambered grooves for buckling the positioning pin; one end of the adjusting rod protrudes out of the sleeve; two sides of each oblong hole are formed with cambered grooves for being buckled by the positioning pin.

[0011] The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 is a schematic view showing one prior art.

[0013] FIG. 2 is another schematic view showing the prior art.

[0014] FIG. 3 is a further schematic view showing a prior art.

[0015] FIG. 4 is a yet schematic view showing the prior art.

[0016] FIG. 5 is a perspective view showing the structure of the present invention.

[0017] FIG. 6 is a lateral schematic view of FIG. 5.

[0018] FIG. 7 is a lateral view showing the angle adjustment of the present invention.

[0019] FIG. 8 is another lateral view showing the angle adjustment of the present invention.

[0020] FIG. 9 is a first perspective view showing the operation of the present invention.

[0021] FIG. 10 is a second perspective view showing the operation of the present invention.

[0022] FIG. 11 is a third perspective view showing the operation of the present invention.

[0023] FIG. 12 is a fourth perspective view showing the operation of the present invention.

[0024] FIG. 13 is a fifth perspective view showing the operation of the present invention.

[0025] FIG. 14 is a sixth perspective view showing the operation of the present invention.

[0026] FIG. 15 is a seventh perspective view showing the operation of the present invention.

[0027] FIG. 16 is a schematic view showing the pivotal point at the upper end of the movable link moving toward a positive angle or a negative angle.

[0028] FIG. 17 is a lateral view of another embodiment of the present invention.

[0029] FIG. 18 is a lateral view of a further embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] At first, referring to FIGS. 5 and 6, the method for adjusting the traveling path of a tread-training device of the present invention are illustrated. One end of the seat 10 of the tread-training device is connected with a supporting rod 11 of a curved handle 111, and another end thereof is installed with a left crank 12 and a right crank 13 which are coaxially arranged. Ends of the left crank 12 and the right crank 13 are pivotally connected to a left treading rod 21 and a right treading rod 22. An angle-adjusting device 30 and a movable link 40 are pivotally installed at the seat 10 near the supporting rod 11.

[0031] The angle-adjusting device 30 includes a sleeve 31 having an end pivotally to the seat 10. A predetermined position of the sleeve 31 is installed with a penetrating hole 311. A positioning pin 312 is inserted into the penetrating hole 311. An adjusting rod 32 is inserted into the sleeve 31. A bank of oblong holes 321 are formed on the middle section of the adjusting rod 32. Two lateral sides of the oblong holes 321 are formed with cambered grooves 322 for buckling the positioning pin 312. One end of the adjusting rod 32 protrudes out of the sleeve 31. The protruding end is moveably and pivotally connected with a front driving arm 33 and a rear driving arm 34. Another end of the front driving arm 33 is pivotally connected to a predetermined position of the supporting rod 11, and another end of the rear driving arm 34 is pivotally and movably to an axial rod 401 of a movable link 40.

[0032] A bottom end of the movable link 40 is pivotally installed to the seat 10. The two sides of the upper end thereof are installed a left driving rod 41 and a right driving rod 42, respectively. One end of the left treading rod 21 is pivotally connected to one end of the left driving rod 41, and one end of the right treading rod 22 is pivotally connected to one end of the right driving rod 42. The upper side of the left treading rod 21 has a pedal 211 and the upper side of the right treading rod 22 has a pedal 222 for being treaded by the user.

[0033] By assembling above components, when the user treads upon the pedals 211 and 222 of the left treading rod 21 and right treading rod 22, a flexible and harmonic elliptical track F is generated so as to achieve the effect of exercising.

[0034] Furthermore, in the angle-adjusting device 30, by adjusting the length of the adjusting rod 32 protruding out of the sleeve 31, then the angle relation between the highest point and the lowest point of pivotal point A of the left treading rod 21 and the left driving rod 41 and the angle relation between the highest point and the lowest point of pivotal point B of the right treading rod 22 and the right driving rod 42 are altered. The angles are altered between +40.degree..about.-30.degree.. Therefore, in the present invention, the slope of the elliptic path E can be altered. Therefore, the tread-training device can be adjusted so that the user may move as along an upward path, a flat path and a downward path. When the length of the adjusting rod 32 protruding out of the sleeve 31 is desired to be adjusted, the positioning pin 312 inserted at the penetrating hole 311 of the sleeve 31 can be drawn out, and then the adjusting rod 32 can be left or descended freely in the sleeve 31. When the uppermost cambered groove 322 of the oblong hole 321 of the adjusting rod 32 is aligned the penetrating hole 311 of the sleeve 31, and then is passed by the positioning pin 312, the front driving arm 33 and rear driving arm 34 at the front and rear ends of the adjusting rod 32 descends. Since one end of font driving arm 33 is pivotally installed and positioned to the supporting rod 11, the sleeve 31 will shift toward the supporting rod 11 automatically. Moreover, one end of the rear driving arm 34 is pivotally installed at the axial rod 401 of the movable link 40, the movable link 40 will incline to the supporting rod 11. Therefore, the elliptic path E is altered. Namely, when the pivotal point A of the left treading rod 21 and the left driving rod 41 and the pivotal point B of the right treading rod 22 and the right driving rod 42 moves, the line from the uppermost point to the lowermost point is formed with a negative angle. Thereby, the actions of the left treading rod 21 and the right treading rod 22 is as in a descent slope (referring to FIGS. 7 and 15). When the lowermost cambered groove 322 of the oblong hole 321 of the adjusting rod 32 is aligned the penetrating hole 311 of the sleeve 31, and then is passed by the positioning pin 312, the front driving arm 33 and rear driving arm 34 at the front and rear ends of the adjusting rod 32, respectively, extend outwards. Since one end of font driving arm 33 is pivotally installed and positioned to the supporting rod 11, the sleeve 31 will shift away from the supporting rod 11 automatically. Moreover, one end of the rear driving arm 34 is pivotally installed at the axial rod 401 of the movable link 40, the movable link 40 will incline away from the supporting rod 11. Namely, when the pivotal point A of the left treading rod 21 and the left driving rod 41 and the pivotal point B of the right treading rod 22 and the right driving rod 42 move, the lines from the uppermost points to the lowermost points are formed with a positive angle. Thereby, the actions of the left treading rod 21 and the right treading rod 22 is as in a rising slope (referring to FIGS. 8 and 9).

[0035] In summary, the lower end of the movable link 40 is pivotal installed to the seat 10 so that in the movable link 40, the pivotal section between the movable link 40 and the seat 10 may be utilized as a fulcrum C, and the pivotal section between the upper end of the movable link 40 and the axial rod 401 is utilized as a movable point (i.e., the pivotal section between the movable link 40 and the left treading rod 21 and right treading rod 22 are used as a movable point D). If the vertical orientation of fulcrum C is as a zero degree, the movable link 40 may be adjusted toward a negative angle or a positive angle (referring to FIG. 16). Therefore, the angle relation between the highest point and the lowest point of pivotal point A of the left treading rod 21 and the left driving rod 41 and the angle relation between the highest point and the lowest point of pivotal point B of the right treading rod 22 and the right driving rod 42 are altered so that Therefore, in the present invention, the slope of the elliptic path E can be altered. Therefore, the tread-training device can be adjusted so that as the user treads the pedals 211, 221 of the left treading rod 21 and right treading rod 22, he may move as along an upward path, a flat path and a downward path.

[0036] Referring to FIGS. 9 to 15, an embodiment about the variation of the elliptic paths E will be described as the angle relation of the line from the highest point to the lowest point of pivotal point A of the left treading rod 21 and the left driving rod 41 and the angle relation of the line from the highest point to the lowest point of pivotal point B of the right treading rod 22 and the right driving rod 42 are altered from the positive 30.degree. to the negative 30.degree..

[0037] In the embodiment about the method for adjusting the traveling path of a tread-training device of the present invention, as illustrated in FIG. 17, in the tread-training device, one end of the seat 10 is connected with a supporting rod 11 of a curved handle 111, and another end thereof is installed with a left crank 12 and a right crank 13 which are coaxially arranged. Ends of the left crank 12 and the right crank 13 are pivotally connected to a left treading rod 21 and a right treading rod 22. A positioning frame 112 having a cambered hole 1121 is installed at the connection portion of the supporting rod 11. The lower end of the cambered hole 1211 has a plurality of grooves which are spaced arranged for positioning the axial rod 401 of the left driving rod 41 and right driving rod 42. Two end of the axial rod 401 are pivotally connected with the left driving rod 41 and the right driving rod 42. Thereby, when the user treads upon the pedals 211 and 222 of the left treading rod 21 and right treading rod 22, a flexible and harmonic elliptical track F is generated so as to achieve the effect of exercising. Moreover, adjusting the axial rod 401 connecting the left driving rod 41 and right driving rod 42 to different groove 1122 at the bottom end of the cambered hole 1211, the angle relation of the line from the highest point to the lowest point of pivotal point A of the left treading rod 21 and the left driving rod 41 and the angle relation of the line from the highest point to the lowest point of pivotal point B of the right treading rod 22 and the right driving rod 42 are altered. Therefore, in the present invention, the slope of the elliptic path E can be altered. Therefore, the tread-training device can be adjusted so that the user may move as along an upward path, a flat path and a downward path.

[0038] Referring to FIG. 18, a schematic view of the second embodiment of the method for adjusting the traveling path of a tread-training device according to the present invention is illustrated. One end of the seat 10 of the tread-training device is connected with a supporting rod 11 of a curved handle 111, and another end thereof is installed with a left crank 12 and a right crank 13 which are coaxially arranged. Ends of the left crank 12 and the right crank 13 are pivotally connected to a left treading rod 21 and a right treading rod 22. An angle-adjusting device 30 and a movable link 40 is pivotally installed at the seat 10 near the supporting rod 11. A bottom end of the movable link 40 is pivotally installed to the seat 10. The two sides of the upper end thereof are installed a left driving rod 41 and a right driving rod 42, respectively. One end of the left treading rod 21 is pivotally connected to one end of the left driving rod 41, and one end of the right treading rod 22 is pivotally connected to one end of the right driving rod 42. The upper side of the left treading rod 21 has a pedal 211 and the upper side of the right treading rod 22 has a pedal 222 for being treaded by the user. Thereby, an elliptical moving path is generated.

[0039] A lifting motor 50 is pivotally installed at a predetermined section of the seat 10 and the movable link 40 In the lift motor 50 has a motor 51 for driving a screw rod 52 Thereby, a screw cover 53 engaged to the screw rod 52 is telescopically. One end of the lift motor 50 is firmly secured to the seat 10. When the motor 51 is actuated, the screw cover 53 will displace forwards and rearwards. The top of the screw cover 53 is pivotally installed to the movable link 40. Therefore, movable link 40 will shift in orientation. Therefore, then the angle relation between the highest point and the lowest point of pivotal point A of the left treading rod 21 and the left driving rod 41 and the angle relation between the highest point and the lowest point of pivotal point B of the right treading rod 22 and the right driving rod 42 are altered. Therefore, in the present invention, the slope of the elliptic path E can be altered. Therefore, the tread-training device can be adjusted so that the user may move as along an upward path, a flat path and a downward path.

[0040] The structure, positions, and assembly way of the present invention has been described above. Next, the advantages of the present invention will be described in the following.

[0041] In the present invention, one ends of the left and right treading rods are connected to one ends of the left and right cranks, and another ends thereof are pivotally installed to the bottoms of a left and right driving rods which may swing freely. The upper ends of the left and right driving rods are pivotally to the same axial rod. In this design, the axial rod can be adjusted and positioned along a round arc path. Thereby, in the present invention, the slope of the elliptic path can be altered. Therefore, the tread-training device is adjusted so that the user may move as along an upward path, a flat path and a downward path. If the center of the axis of the round arc formed by the path is used as a reference line of zero degree, then the axial rod can be adjusted to a positive or a negative angles (referring to FIG. 16).

[0042] The two ends of the left treading rod and right treading rod are pivotally connected by bearings. No other parts or specific track device is necessary in the treading operation. Therefore, the friction forces due to the contacts of the parts can be reduced and thus the wearing of the parts are greatly reduced to almost zero.

[0043] By adjusting the length of the adjusting rod protruding out of the sleeve, then the angle relation between the highest point and the lowest point of pivotal point of the left treading rod and the left driving rod and the angle relation between the highest point and the lowest point of pivotal point of the right treading rod and the right driving rod are altered.

[0044] The above angle-adjusting device is only one embodiment for described the present invention. Other means may alter the angle of the movable link of the present invention can be used in the present invention.

[0045] Although the present invention has been described with reference to the preferred embodiments, it will be understood that the invention is not limited to the details described thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.

Claims

What is claimed is

1. A method for adjusting the traveling path of a tread-training device; the tread-training device having a seat; one end of the seat of the tread-training device being connected with a curved handle, and another end thereof is installed with a left crank and a right crank which are coaxially arranged; ends of the left crank and the right crank are pivotally connected to a left treading rod and a right treading rod; and another ends of the left treading rod and right treading rod being pivotally to end portions of a left driving rod and a right treading rod which are capable of swinging forwards and rearwards freely; characterized in that: the axial rod moves along a cambered path so that the orientations of the left driving rod and right driving rod are altered or a highest point and a lowest point of a pivotal point of the left treading rod and the left driving rod and a highest point and a lowest point of a pivotal point of the right treading rod and the right driving rod are altered so that tracks of moving path of the treading rods are altered; therefore, the tread-training device is adjusted so that the user moves as along an upward path, a flat path and a downward path

2. The method for adjusting the traveling path of a tread-training device as claim in claim 1, wherein a vertical line from a center of an axis of a round arc formed by the path is used as a reference line of zero degree, then the axial rod is adjusted to and positioned in a positive or a negative angles with respect to the vertical line.

3. The method for adjusting the traveling path of a tread-training device as claim in claim 2, wherein pivotal sections of upper ends of the left driving rod and right driving rod and the axial rod are further connected with a movable link, thereby, the axial rod moves forwards and rearwards, and thus the treading rods move continuously along a round path.

4. The method for adjusting the traveling path of a tread-training device as claim in claim 3, wherein one end of the movable link is pivotally installed at a predetermined position of the seat, said predetermined position is utilized as a fulcrum for swinging forwards and rearwards.

5. The method for adjusting the traveling path of a tread-training device as claim in claim 3, further comprising an angle-adjusting device for displacing and positioning the movable link.

6. The method for adjusting the traveling path of a tread-training device as claim in claim 5, wherein the angle-adjusting device has a sleeve with one end being pivotally connected to the seat; the sleeve has an adjusting rod; one end of the adjusting rod protrudes out of the sleeve; the protruding end is moveably and pivotally connected with a front driving arm and a rear driving arm; another end of the front driving arm is pivotally connected to a predetermined position of the supporting rod, and another end of the rear driving arm is pivotally and movably to the axial rod of the movable link; wherein when moving the adjusting rod, the orientations of the font driving arm and rear driving arm are altered so that a pivotal point of the left treading rod and the left driving rod and a highest point and a pivotal point of the right treading rod and the right driving rod are altered and thus tracks of moving path of the treading rods are altered; therefore, the tread-training device is adjusted so that the user moves as along an upward paths a flat path and a downward path.

7. The method for adjusting the traveling path of a tread-training device as claim in claim 1, wherein when moving the adjusting rod, a highest point and a lowest point of a pivotal point of the left treading rod and the left driving rod and a highest point and a lowest point of a pivotal point of the right treading rod and the right driving rod are altered and thus tracks of moving path of the treading rods are altered; therefore, the tread-training device is adjusted so that the user moves as along an upward path, a flat path and a downward path.

8. The method for adjusting the traveling path of a tread-training device as claim in claim 5, wherein the angle-adjusting device is between the supporting rod and the movable link.

9. The method for adjusting the traveling path of a tread-training device as claim in claim 5, wherein a predetermined position of the sleeve is installed with a penetrating hole; a positioning pin is inserted into the penetrating hole; an adjusting rod is inserted into the sleeve; a bank of oblong holes are formed on the middle section of the adjusting rod; two lateral sides of the oblong holes are formed with cambered grooves for buckling the positioning pin; one end of the adjusting rod protrudes out of the sleeve; two side of each oblong hole are formed with cambered grooves for being buckled by the positioning pin.

10. A method for adjusting the traveling path of a tread-training device; the tread-training device having a seat; one end of the seat is connected with a supporting rod of a curved handle; and another end thereof is installed with a left crank and a right crank which are coaxially arranged; ends of the left crank and the right crank are pivotally connected to a left treading rod and a right treading rod; characterized in that: the supporting rod has a positioning frame having a cambered hole; a lower end of the cambered hole has a plurality of grooves which are spaced arranged for positioning the axial rod of the left driving rod and right driving rod; two end of the axial rod are pivotally connected with a left driving rod and a right driving rod; thereby, when the user treads upon pedals of the left treading rod and right treading rod, a flexible and harmonic elliptical track is generated; adjusting the axial rod connecting the left driving rod and right driving rod to different groove at a bottom end of the cambered hole, the angle relation of the line from the highest point to the lowest point of pivotal point of the left treading rod and the left driving rod and the angle relation of the line from the highest point to the lowest point of pivotal point of the right treading rod and the right driving rod are altered; therefore, the slope of the elliptic path is altered, and the tread-training device is adjusted so that the user moves as along an upward path, a flat path and a downward path.

11. A method for adjusting the traveling path of a tread-training device; the tread-training device having a seat; one end of the seat of the tread-training device being connected with a supporting rod of a curved handle, and another end thereof being installed with a left crank and a right crank which being coaxially arranged; ends of the left crank and the right crank being pivotally connected to a left treading rod and a right treading rod; a movable link being pivotally installed at the seat near the supporting rod; a bottom end of the movable link being pivotally installed to the seat; the two sides of the upper end thereof being installed a left driving rod and a right driving rod, respectively; one end of the left treading rod being pivotally connected to one end of the left driving rod, and one end of the right treading rod being pivotally connected to one end of the right driving rod; an upper side of the left treading rod having a pedal and the upper side of the right treading rod having another pedal for being treaded by the user; thereby, an elliptical moving path being generated; characterized in that: a lifting motor is pivotally installed at a predetermined section of the seat and the movable link; the lift motor has a motor for driving a screw rod; thereby, a screw cover engaged to the screw rod is s telescopically; one end of the lift motor is firmly secured to the seat; when the motor is actuated, the screw cover will displace forwards and rearwards. The top of the screw cover is pivotally installed to the movable link. Therefore, movable link will shift in orientation. Therefore, then the angle relation between the highest point and the lowest point of a pivotal point of the left treading rod and the left driving rod and the angle relation between the highest point and the lowest point of a pivotal point of the right treading rod and the right driving rod are altered; therefore, a slope of the elliptic path is changeable, and thus the tread-training device is adjusted so that the user moves as along an upward path, a flat path and a downward path.