Patent Publication Number: US-5255886-A

Title: Rotating device for Christmas tree

Description:
BACKGROUND OF THE INVENTION 
     (a) Field of the Invention 
     The present invention relates to a rotating device for Christmas tree, particularly a device to serve as a base of Christmas tree and to twinkle bulbs on the Christmas tree. 
     (b) Description of the Prior Art 
     Conventionally a freely rotating turntable connected to a power source is used to rotate Christmas tree. Such a design requires some carbon brushes with springs extending outside the turntable to maintain rotating. Since the carbon brushes are simple electric conductors, they can not permit steady rotation of Christmas tree having a considerable weight. Moreover, the use of carbon brushes can maintain steady power supply, aging of the springs would make the carbon brushes unable to maintain good contact with power source. 
     SUMMARY OF THE INVENTION 
     The main object of the present invention is to provide a rotating device for Christmas tree which uses a reducing motor to drive a rotating gear with a plurality of matching holes and fixed with two annular electric conductors on its surface to assure steady power supply and help leading of conductor wires for a rotating Christmas tree. 
     Another object of the present invention is to provide a rotating device for Christmas tree which has a support with a plurality of steel balls beneath the rotating gear to facilitate rotating and to assure steady rotation of a Christmas tree of a considerable weight. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a rotating device for Christmas tree according to the present invention. 
     FIG. 2 is a perspective fragmented view of the rotating device according to the present invention. 
     FIG. 3 is a sectional view of the rotating device according to the present invention. 
     FIG. 4 is a sectional view illustrating assembly of the rotating gear and two fixed conductors on a bracket according to the present invention. 
     FIG. 5 is a sectional view of another embodiment of the present invention, including a support with a plurality of steel balls. 
     FIG. 6 is a bottom view of the assembly of the rotating gear and the support in FIG. 5. 
     FIG. 7 is a sectional view illustrating assembly of the steel balls in FIG. 5. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Please refer to FIGS. 1 through 4, the rotating device for Christmas tree according to the present invention comprises mainly a shell (1), a bracket (2), a reducing motor (3), a rotating gear (4), and two annular electric conductors (51 and 52). 
     The shell (1) can be in any shape (e.g., sphere, cube or other form) to meet different requirements, and is composed of an upper shell element (11) and a lower shell element (12). 
     The bracket (2) is a frame with an appropriate configuration to be fixed within the shell (1). A cylindrical post (21) is designed on the bracket (2). two fixed conductors (22) are fixed at opposite sides of the cylindrical post (21). 
     The reducing motor (3) is secured to the bracket (2) with a fixing plate (31). The reducing motor (3) is incorporated with a driving gear (32) engaging with the rotating gear (4). With its characteristics, the reducing motor (3) can be run steadily and slowly to drive the rotating gear (4). 
     The rotating gear (4) is made of a non-electric conductive insulating material. It is engaged with the aforesaid driving gear (32), and has an appropriate gear ratio for a suitable rotation speed. The rotating gear (4) has a shaft sleeve (41) with an inner sleeve (42) extended from its center. A plurality of longitudinal slots (411) is formed on the wall of the shaft sleeve (41) from its upper end. The upper end of the shaft sleeve (41) is formed with an appropriate flange (412). On the surface of the gear (4) there is a plurality of matching holes (43) for fixing of two annular electric conductors (51 and 52). 
     The two annular electric conductors (51 and 52) are of different diameter, but all incorporated with a plurality of fixing elements (511 or 521) for positioning at the matching holes (43) on the rotating gear (4). 
     For assembly of the above described components, the shaft sleeve (41) of the rotating gear (4) is placed within the cylindrical post (21) of the bracket (2). The flange (412) on the shaft sleeve (41) is then rested on the upper edge of the cylindrical post (21) extending out of the shell (1), and a trunk (6) of a Christmas tree can be inserted to and secured by the inner sleeve (42) in the shaft sleeve (41). The fixed conductors (22) of the bracket (2) is for connecting to a power source cord (7). Each of the annular electric conductors (51 and 52) has a connecting element (511 or 421) at the bottom for connecting to a wire (8) passing through a longitudinal slot (411) to connect to a plug (81) connecting a power source to a series of Christmas lamps as shown in FIG. 3. 
     Please refer to FIGS. 3 and 4, each fixed conductor (22) on the bracket (2) has an appropriately bent and elastic end to keep good contact with an annular electric conductors (51 or 52) even during rotation of the present invention. 
     The present invention may include a speaker (9) to play music at the bracket (2) if required for use on Christmas tree, and a knob (13) on the shell (1) for control of volume. However, the incorporation of such speaker is a conventional skill and it not a feature of the present invention, hence it is not to be described in detail herein. 
     Moreover, within the spirit of the present invention, a support (10) can be designed beneath the rotating gear (4), as shown in FIGS. 5 through 7. The support (10) has an appropriate annular groove (101), and the annular groove (101) has a recession (102) for filling of lubricant at the bottom. A plurality of steel balls (103) are placed in the annular groove (101, and an appropriate sliding strip (44), such as a steel or copper strip, is located on the bottom of the rotating gear (4) at a position corresponding to the annular groove (101) to help smooth rotation of the 
     rotating gear (4), and to assure the present invention 
     to maintain a steady rotation with a Christmas tree of 
     considerable weight.