TREADMILL

Description

BACKGROUND OF INVENTION

1. Field of Invention

The present invention relates to a treadmill and, more particularly, to a safety device for a treadmill.

2. Related Prior Art

A conventional treadmill suffers detachment of a wheel from an axle. To solve this problem, the present applicant has been devised a coaxial-rotation mechanism and obtained U.S. Pat. No. 11,198,034 for it. In this patent, two bearings are arranged between a roller and an axle to allow smooth rotation of the roller around the axle.

The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art.

SUMMARY OF INVENTION

It is the primary objective of the present invention to provide a safe-to-use treadmill.

To achieve the foregoing objective, the treadmill includes a frame, a primary transmission unit supported by the frame, a secondary transmission unit supported by the frame, and a caterpillar extending around the transmission units so that the primary and secondary transmission units keep the caterpillar in proper tension. The primary transmission unit includes a roller including an axle non-rotationally connected to the frame, a tube rotationally extending around the axle, and two bearings arranged between the axle and the tube to render the tube rotatable around the axle in one direction but no vice versa.

Other objectives, advantages and features of the present invention will be apparent from the following description referring to the attached drawings.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will be described via detailed illustration of two embodiments referring to the drawings wherein:

FIG. 1 is a perspective view of a treadmill according to the first embodiment of the present invention;

FIG. 2 is an enlarged partial view of the treadmill shown in FIG. 1;

FIG. 3 is an exploded view of the treadmill shown in FIG. 2;

FIG. 4 is a cross-sectional view of the treadmill shown in FIG. 2; and

FIG. 5 is a partial top view of a treadmill according to the second embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring to FIG. 1, a treadmill 10 includes a frame 11, a caterpillar 13, a handlebar 19 and two transmission units 20 according to the preferred embodiment of the present invention. The frame 11 supports the caterpillar 13, the handlebar 19 and the transmission units 20.

The frame 11 includes crossbars (not numbered) located between and connected to longitudinal bars (not numbered). Pads (not numbered) are movably attached to a lower side of the frame 11. The pads are operable to render the frame 11 stable on a floor. Casters (not numbered) are attached to the lower side of the frame 11. The casters are operable to render travel of the frame 11 on the floor smooth and easy. Two decorative strips 12 are attached to the frame 11.

The caterpillar 13 includes slabs 14 extending side by side. The caterpillar 13 is supported by the frame 11 and located between the decorative strip 12. The caterpillar 13 includes a front section 15, a rear section 16, an upper section 17 on the frame 11 and a lower section 18 beneath the frame 11. Both the upper section 17 and the lower section 18 extend in an arched manner due to weight so that the treadmill 10 is sometimes referred to as “arched treadmill.” The caterpillar 13 extends around the transmission units 20.

The treadmill 10 may or may not be equipped with a motor (not shown). In the case where not motor is used for the treadmill 10, the caterpillar 13 is only moved by an exerciser walking, jogging or running on the upper section 17 of the caterpillar 13.

The handlebar 19 is connected to two posts (not numbered) which are attached to the frame 11. The exerciser can hold the handlebar 19 while walking, jogging or running on the upper section 17 of the caterpillar 13.

When the caterpillar 13 moves around the transmission units 20 in a direction 30, each of the slabs 14 is in the front section 15 in a period of time, in the upper section 17 in another period of time, in the rear section 16 in another period of time, and in the lower section 18 in another period of time

The user can hold the handlebar 19 and hence is protected from falling while stepping onto the upper section 17 of the caterpillar 13.

When the caterpillar 13 moves around the transmission units 20 in a direction 32, each of the slabs 14 is in the front section 15 in a period of time, in the lower section 18 in another period of time, in the rear section 16 in another period of time, and in the upper section 17 in another period of time.

However, the movement of the caterpillar 13 around the transmission units 20 in the direction 32 is not desired. To this end, one of the transmission units 20 is used to prevent the caterpillar 13 from moving in the second direction 32. Thus, the exerciser is safe while stepping down from the upper section 17 of the caterpillar 13.

Referring to FIG. 3, each of the transmission units 20 includes two pulleys 21 and a roller 22. The axle 23 includes two ends connected to the frame 11. The axle 23 is not rotatable on the frame 11. The tube 24 includes two ends respectively connected to the pulleys 21 so that the pulleys 21 are rotatable with the tube 24.

Referring to FIG. 2, the axle 23 extends throughout the tube 24 so that the ends of the axle 23 are located out of the tube 24. The caterpillar 13, which consists of the slabs 14, moves the pulleys 21 (FIG. 3). The transmission units 20, which are supported by the frame 11, keep the caterpillar 13 in proper tension.

Referring to FIG. 4, each of the transmission units 20 further includes two bearings 25 and 26 located between the axle 23 and the tube 24. The pulleys 21 and the tubes 24 are coaxially rotatable around the axle 23. The bearing 25 is a two-way bearing 25. The bearing 26 is a one-way bearing 26. The two-way bearing 25 is rotatable in two directions. The one-way bearings 26 is rotatable in only one direction.

Referring to FIG. 1 again, the transmission units 20 allow the caterpillar 13 to move in the direction 30 due to the use of the bearings 25 and 26. The transmission units 20 prevent the caterpillar 13 from moving in the direction 32 due to the use of the one-way bearing 26. Thus, the exerciser is protected while stepping down from the upper section 17 of the caterpillar 13 of the treadmill 10.

Referring to FIG. 5, there is a treadmill according to a second embodiment of the present invention. The second embodiment is identical to the first embodiment except for additionally including a sport mode simulation system 34 connected to one of the transmission units 20. Preferably, the sport mode simulation system 34 is connected to the pulleys 21. The sport mode simulation system 34 is operable to simulate a horizontal mode, a mildly up-hill mode and a step mode.

The present invention has been described via the illustration of the preferred embodiment. Those skilled in the art can derive variations from the preferred embodiment without departing from the scope of the present invention. Therefore, the preferred embodiment shall not limit the scope of the present invention defined in the claims.