US 20020142889 A1
A transmitting device for a walking machine includes a first and a second shaft positioned in parallel to each other. A first wheel is fixed on the first shaft, and a third wheel of a smaller diameter than the first wheel is fixed on the second shaft and rotated by the first wheel through a belt. Further a fourth wheel having a diameter smaller than the third wheel is fixed on the second shaft, rotating the second wheel through another belt. The second wheel rotates a flywheel fixed on the first shaft by means of a bearing. The transmitting device may function as two wheels and two stages under the same speed, compared with a conventional transmitting device for a walking machine, having a smaller size and a flywheel made larger to increase rotating inertial of the flywheel and consequent smoothness of pedaling.
1. A transmitting device for a walking machine comprising:
A first shaft having a first wheel fixed thereon to rotate together, a flywheel also fixed on said first shaft by means of a bearing, and a second wheel also fixed on the first shaft just beside said flywheel by means of another bearing:
A second shaft positioned in parallel to said first shaft, having a third wheel and a fourth wheel fixed thereon to rotate together, said third wheel having a smaller diameter than that of said first wheel, said first wheel and said third wheel rotated by a same belt, said fourth wheel having a larger diameter than those of said second and said third wheel, said second wheel and said fourth wheel rotated by another same belt:
Thus said transmitting device having function of two shafts and two stages so as to reduce its size and permit said flywheel made comparatively large to increase rotating inertia and consequent smoothness of pedaling.
 This invention relates to a transmitting device for a walking machine, particularly to one having small dimensions under the same speed, comparatively capable to control precision of shaft paralleling of the machine, elevating smoothness in pedaling and producing efficacy.
 Some conventional oval route walking machines have a flywheel-transmitting device of “one stage and two shafts” and others have that of “two stages and three shafts”. They all have disadvantages in practical use described below.
 1. The transmitting device of so called “one stage and two shafts” is shown in FIG. 1, including, a transmitting wheel 1 of a large diameter and a passive wheel 2 of a small diameter to match the transmitting wheel 1, (the passive wheel 2 is fixed on the same shaft of a flywheel controlled by a brake resistance), and the two wheels 1 and 2 are rotated by a belt 3. Although this kind of transmitting device has small dimensions, the transmitting wheel 1 requires a very large diameter to get the same speed. In other words, the diameter proportion of the two wheels 1 and 2 has to be large so that the belt 3 with a small angle may cover the passive wheel 2. The covering angle is generally larger than 180 degrees, or the belt 3 may slide, and a pressing member 4 has to be provided to press the belt 3 so as to prevent the belt 3 from sliding for increasing the covering angle as shown in FIG. 1. Then the belt 3 may not slide, but the belt 3 may lower its service life.
 2. The other “two stage and three shafts” of the transmitting device shown in FIG. 2 includes a transmitting wheel 5 of a large diameter or the wheel driven by pedaling, an intermediate wheel 6 of a smaller diameter than the wheel 5 and a passive wheel 7 of a smaller diameter than that of the intermediate wheel 6. The three wheels 5, 6 and 7 are arranged in parallel to one another. Further, a second intermediate wheel 60 of a comparative small diameter is fixed on the same shaft of the intermediate wheel 5, and an active belt 8 extends around the transmitting wheel 5 and the second intermediate wheel 60. A passive belt 9 is provided to extend around the intermediate wheel 6 and the passive wheel 7 so that the intermediate wheel 6 and the passive wheel 7 may rotate when a foot rotates the transmitting wheel 5. Under the same speed, the three wheels 5, 6 and 7 of the rather small diameters may be covered with a large angle by the belts 8 and 9, improving the defect of belt sliding. But the machine body may need a large space, resulting in the flywheel on the same shaft of the passive wheel may shrink in its size. From the point of inertia angle, rotating inertial and the diameter of the flywheel may have direct proportion, and the larger the flywheel, the better the rotating inertia. So a user can pedal with smoothness, but the two stages and three shafts structure have a large size, impossible to enlarge the flywheel any more. Should the flywheel be enlarged, the wholeness of the machine body may be affected. So a user may not be able to pedal smoothly. In addition, to ensure interactive stability of the two stages and the three shafts, the shaft parallel between the transmitting wheel 5 and the intermediate wheel 6 and between the intermediate wheel 6 and the passive wheel 7 should be made very accurate, as shown in FIG. 3, in order to obtain smoothness of the interactive structure. Then its assembly may be difficult and the shaft precision hard to control, taking time in assembling.
 The objective of the invention is to offer a transmitting device for a walking machine, which has a small size and good controllability in shaft precision to save time in assembling, and a flywheel of a comparatively large diameter to elevate rotating inertia in pedaling.
 This invention will be better understood by referring to the accompanying drawings, wherein:
FIG. 1 is a simple view of a transmitting device of a conventional oval-route walking machine:
FIG. 2 is a simple view of another transmitted device of a conventional oval-route walking machine:
FIG. 3 is an exploded perspective view of FIG. 2:
FIG. 4 is a side view of a transmitting device combined with a walking machine for a walking machine in the present invention:
FIG. 5 is an upper view of the transmitting device for walking machine in the present invention:
FIG. 6 is a side view of the transmitting device for a walking machine in the present invention.
 A preferred embodiment of a transmitting device 30 for a walking machine in the present invention, as shown in FIG. 4, is mainly utilized in an oval-route walking machine and combined with a frame body 10, and a pair of pedal plates 20.
 The transmitting device 30 includes a first shaft 31, a first wheel 32, a flywheel 33, a second wheel 34, a second shaft 35, a third wheel 36, a fourth wheel 37 as main components combined together.
 The first shaft 31 is driven directly by the pair of pedals 20, and the first wheel 32 is fixed on the first shaft 31 to rotate together. The first wheel 31 is positioned by a bearing 310 at its inner side and the flywheel 33 is fixed on the first shaft 31 and located just beside the first wheel 32. Further a resistance adjusting device is provided at an outer edge of the flywheel 33, supplying resisting force to the flywheel 33 to adjust the force of gravity in pedaling.
 The second wheel 34 is fixed on the first shaft 31 by means of another bearing 310, abutting on an outer side of the flywheel 33, rotated together with the second wheel 34.
 The second shaft 35 is positioned in parallel to the first shaft 31, and the third wheel 36 with a smaller diameter than that of the first wheel 32 is fixed on the second shaft 35 corresponding to the first wheel 32.
 The fourth wheel 37 is fixed on the second shaft 35 to rotate together, having a larger diameter than those of the third wheel 36 and the second wheel 34.
 A belt 38 rotates the first wheel 32 and the third wheel 36 at the same time, and a belt 39 rotates the second wheel 34 and the fourth wheel 37 at the same time. Thus, the transmitting order of the transmitting device 30 begins with the pedaling plates 20 to the first shaft 31, then to the first wheel 32, then to the belt 38, then to the third wheel 36, then to the second shaft 35, then to the forth wheel 37, then to the belt 39, then to the second shaft 34 and finally to the flywheel 33. Therefore, a speed proportion preset may be attained by different diameters of the four wheels 32, 34, 36 and 37 so as to rotate the flywheel 33.
 The transmitting device for a walking machine in the invention has advantages in using as below, as may be understood from the aforesaid description.
 1. It has an effect caused by two stages and two shafts of the first and the second shafts 31 and 35 under the same speed proportion, and the covering angles between the wheels and the belts are larger than 180 degrees, getting rid of machinery damage or sliding of the belts.
 2. It has a small size after assembled, and the flywheel possible to be made comparatively large to increase rotating inertia and consequent smoothness of pedaling.
 3. It has only two shafts, rather easy to control parallel relation of the two shafts, saving work and time in assembling.
 While the preferred embodiment of the invention has been described above and it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications that may fall within the spirit and scope of the invention.