Music crystal ball structure capable of rotating in alternating directions

A music crystal ball structure capable of rotating in alternating directions. A music bell serves as a power source for transmitting power to a mutilated gear which further transmitting the power to a gear member having inner circumferential teeth and outer circumferential teeth. The gear member is driven to rotate in alternating directions. For example, the gear member is counterclockwise rotated through an angle and then clockwise rotated through another angle. Such movement is circularly repeated to form a "forward 3, backward 1" state. By means of more than one set of gears, the decorative articles installed in the crystal ball and driven by the gear member can act like dancing opposite to each other and create a dynamic live view.

BACKGROUND OF THE INVENTION 
The present invention relates to a music crystal ball structure capable of 
rotating in alternating directions. The music crystal ball includes a 
mutilated gear and a specific gear member having inner circumferential 
teeth and outer circumferential teeth. The gear member serves to drive 
decorative articles installed in the crystal ball to lively and 
dynamically act. 
In a generally seen music crystal ball, a decorative article is able to 
continuously rotate in one direction. Such rotational action is monotonous 
without variation and fails to attract a consumer. 
SUMMARY OF THE INVENTION 
It is therefore a primary object of the present invention to provide a 
music crystal ball structure capable of rotating in alternating 
directions. In the music crystal ball, a music bell serves as a power 
source for transmitting power to a mutilated gear which further 
transmitting the power to a gear member having inner circumferential teeth 
and outer circumferential teeth. The gear member is driven to rotate in 
alternating directions. For example, the gear member is counterclockwise 
rotated through 250 degrees and then clockwise rotated through 80 degrees. 
Then the gear member is again counterclockwise rotated through 250 
degrees. Such movement is circularly repeated to form a "forward 3, 
backward 1" rotational action. By means of another set of gears, the 
decorative articles installed in the crystal ball and driven by the gear 
member can act like dancing opposite to each other and create a dynamic 
live view for attracting a consumer. 
The present invention can be best understood through the following 
description and accompanying drawings, wherein:

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Please refer to FIGS. 1, 2 and 3. The present invention includes a fixing 
board 1 disposed with four upright supporting posts 13. The top end of 
each supporting post 13 is formed with a small hole 14 for fixing a music 
bell 21 on the fixing board 1 in an upright state. A rotary shaft 24 
laterally extends from the music bell 21 for winding the music bell. In 
addition, the fixing board 1 is formed with a recess 12, whereby a lower 
section of the music bell 21 is fitted in the recess 12. A front stopper 
wall 11 is disposed on front edge of the recess 12, whereby the music bell 
21 can lean against the stopper wall 11. A transmission shaft 22 extends 
out of the music bell 21. A front thread section of the transmission shaft 
22 is screwed into a thread hole of a copper sleeve 23. The outer 
periphery of the copper sleeve 23 is formed with engaging teeth, whereby 
when the copper sleeve 23 is fitted with a mutilated gear 3, the engaging 
teeth are tightly engaged in a toothed central hole 32 of the mutilated 
gear 3, so that the power can be transmitted from the music bell 21 
through the transmission shaft 22 to the mutilated gear 3. 
The mutilated gear 3 is engaged with a specifically designed gear member 
71. Please refer to FIGS. 2 to 5. The gear member 71 is substantially 
disc-shaped, including inner circumferential teeth 71 formed on inner side 
of the circumference of the disc and outer circumferential teeth 72 formed 
around a central shaft hole 73 of the disc. The inner teeth 71 and the 
outer teeth 72 are integrally connected with the gear member 7. Referring 
to FIGS. 4 and 5, when the teeth 31 of the mutilated gear 3 are engaged 
with the inner teeth 71 of the gear member 7 and the mutilated gear 3 is 
rotated clockwise (seen from upper side), the gear member 7 is driven to 
rotate also in clockwise direction. Following the continuous rotation of 
the mutilated gear 3, the teeth 31 thereof are gradually disengaged from 
the inner teeth 71 and further engaged with the outer teeth 72. At this 
time, the gear member 7 is driven to rotate in a reverse direction, that 
is, counterclockwise direction. Following the continuous rotation of the 
mutilated gear 3, the teeth 31 are disengaged from the outer teeth 72 and 
further engaged with the inner teeth 71. At this time, the gear member 7 
is again rotated clockwise. Therefore, the gear member 7 is repeatedly 
rotated in alternating directions. 
The present invention is characterized in that the operation of the gear 
member 7 is different from the left and right symmetrical swinging 
movement. The generally seen swinging movement is that the member is 
clockwise rotated through an angle and then counterclockwise rotated 
through an equal angle. However, when the teeth 31 of the mutilated gear 3 
are engaged with the inner teeth 71 of the gear member 7, the gear member 
7 is driven to rotate through a first angle. When the teeth 31 of the 
mutilated gear 3 are engaged with the outer teeth 72 of the gear member 7, 
the gear member 7 is driven to rotate through a second angle. The former 
is less than the latter and the ratio of the first angle to the second 
angle is about d (the diameter of the dividing circle of the outer teeth) 
: D (the diameter of the dividing circle of the inner teeth). Due to the 
difference between the movements, the operation effect of the decorative 
article 10 driven by the gear member 7 will be different from the general 
swinging movement. That is, the decorative article 10 will first rotate 
through the second angle and then rotate back through the first angle and 
then rotate forward through the second angle and then rotate back through 
the first angle. In the case that the decorative article 10 is seen from 
one single direction, the front, back, left and right sides of the 
decorative article 10 can be all eventually all seen. The decorative 
article 10 will thus form a "forward 3, backward 1" view. 
As shown in FIG. 2, a supporting tray 6 is disposed under the gear member 7 
for placing the gear member 7 therein. One side of the supporting tray 6 
is formed with a through hole 61 for the mutilated gear 3 to pass 
therethrough to engage with the inner and outer teeth 71, 72 of the gear 
member 7. In addition, the periphery of the supporting tray 6 is formed 
with four small holes 63 for four screws 65 to pass therethrough to 
tighten the supporting tray 6 on the fixing posts 13 of the fixing board 
1. A central transmission shaft 42 has an upper rectangular head 421 
inserted in a central rectangular hole 81 of a four-claw tray 8. A middle 
section 422 thereof is disposed with outer teeth for tightly fitting in 
the central hole 73 of the gear member 7 for transmitting torque. A lower 
section 423 thereof is slidably fitted in the central hole 62 of the 
supporting tray 6 for restricting radial displacement thereof. After 
assembled, the four-claw tray 8, gear member 7 and the supporting tray 6 
are serially connected to the central transmission shaft 42. The bottom 
end thereof is engaged with an engaging spring 41 for restricting axial 
displacement thereof. FIG. 3 shows that the present invention is applied 
to a crystal ball to continuously change direction of the rotation so as 
to create a dynamic and unique appearance. 
Referring to FIG. 6, the upper end of the central transmission shaft 42 is 
further connected with a gear 91 horizontally meshing with another gear 92 
having a central transmission shaft 42'. Accordingly, two decorative 
articles driven by the central transmission shafts 42, 42' can act like 
dancing opposite to each other. 
FIG. 7 shows another embodiment of the present invention, in which the 
structure is simplified and the volume is reduced. The fixing board 1 is 
simplified to only provide fixing effect for the music bell 21. The 
transmission shaft 22 of the music bell 21 is directly connected with an 
end face gear 25 which perpendicularly meshes with a gear 26. The gear 26 
via a short shaft 27 is connected with the mutilated gear 3 for 
transmitting power. The mutilated gear 3 then is engaged with the gear 
member 7 so that the gear member 7 can continuously rotate in alternating 
directions. The supporting tray 6 via screws 65 and through holes 63 are 
fixed on a bridge support 5. The gear 26 and the mutilated gear 3 are 
restricted via the short shaft 27 passing through the small hole 61 and 
the through hole 52. The bridge support 5 is fixed via the thread holes of 
the music bell 21. The central hole 53 thereof coincides with the central 
axis of the music bell 21. Also, the central axes of the gear member 7 and 
the transmission shaft 42 coincide with the central axis of the music bell 
21. Such structure is symmetrical about the center and the respective 
parts are positioned within the circumferential range of the music bell 21 
(generally 60 mm) so that such structure is applicable to various kinds of 
artistic works with small volume and can be easily assembled and 
disassembled. 
It is to be understood that the above description and drawings are only 
used for illustrating some embodiments of the present invention, not 
intended to limit the scope thereof. Any variation and derivation from the 
above description and drawings should be included in the scope of the 
present invention.