Ceiling fan

Abstract

A ceiling fan includes a transmission unit for decoration. The transmission unit includes a base seat connected to a stator axle of a rotating motor for driving a blade module, a sun gear disposed rotatably on the base seat, a driving motor disposed on the base seat, and a first planet gear connected to the driving motor and meshing with the sun gear. The driving motor drives the first planet gear to rotate the sun gear. The sun and first planet gears are exposed at a bottom side of the base seat so as to be externally visible.

What is claimed is: 
     
         1 . A ceiling fan comprising:
 a hanging base;   an upper casing connected to said hanging base;   a rotating motor disposed in said upper casing and including a stator axle that extends along an axis and a rotor seat that is rotatably mounted to said stator axle;   a blade module connected to said rotor seat and including a plurality of fan blades that are displaced angularly from each other; and   a transmission unit including a base seat that is connected to a bottom of said stator axle, a sun gear that is disposed rotatably on said base seat, a driving motor that is disposed on said base seat, and a first planet gear that is connected to said driving motor and that meshes with said sun gear, said driving motor driving said first planet gear to rotate said sun gear, said sun and first planet gears being exposed at a bottom side of said base seat so as to be externally visible.   
     
     
         2 . The ceiling fan as claimed in  claim 1 , wherein said transmission unit further includes at least one second planet gear disposed rotatably on said base seat and meshing with said sun gear. 
     
     
         3 . The ceiling fan as claimed in  claim 2 , wherein said at least one second planet gear includes two second planet gears. 
     
     
         4 . The ceiling fan as claimed in  claim 2 , wherein a ratio of a rotational speed of said sun gear to that of said first planet gear is 0.5, and a ratio of a rotational speed of said at least one second planet gear to that of said sun gear is 2. 
     
     
         5 . The ceiling fan as claimed in  claim 4 , wherein an output speed of said driving motor is 6 revolutions per minute. 
     
     
         6 . The ceiling fan as claimed in  claim 2 , wherein said first planet gear and said at least one second planet gear are equiangularly arranged about said sun gear. 
     
     
         7 . The ceiling fan as claimed in  claim 3 , further comprising a transparent lower cover connected to said base seat and disposed below said transmission unit, said sun, first planet and second planet gears being externally visible through said lower cover. 
     
     
         8 . The ceiling fan as claimed in  claim 7 , wherein:
 said base seat has an upper seat plate connected to said stator axle, and a lower seat plate connected to said upper seat plate and having an axle portion that extends downwardly along the axis, said upper seat plate having a central part whose bottom side is covered by said lower seat plate and a lateral part that surrounds said central part and that has a bottom side exposed around said lower seat plate;   said driving motor is disposed on an upper side of said upper seat plate and has an output axle extending downwardly through said upper seat plate; and   said sun gear is connected to said axle portion of said lower seat plate, said first planet gear being connected to said output axle and disposed below said lateral part of said upper seat plate, said at least one second planet gear being disposed on a bottom surface of said lateral part of said upper seat plate.   
     
     
         9 . The ceiling fan as claimed in  claim 8 , further comprising a hanging tube extending along the axis and interconnecting said hanging seat and said upper casing, said stator axle having an axle hole, said base seat defining an axle passage that extends from a top end of said upper seat plate to a bottom end of said lower seat plate and that is in spatial communication with said axle hole of said stator axle. 
     
     
         10 . The ceiling fan as claimed in  claim 9 , further comprising:
 an axle extension sleeve connected to said axle portion of said lower seat plate, and having a sleeve hole that is in spatial communication with said axle passage;   a connecting plate connected to said axle extension sleeve, said lower cover being connected to said connecting plate and surrounding said axle extension sleeve;   a switch box mounted to said connecting plate and disposed below said lower cover, said axle extension sleeve extending downwardly into said switch box;   a switch cover mounted to said switch box and covering a bottom side of said switch box; and   a decorative button mounted to said switch cover and disposed below said axle extension sleeve.   
     
     
         11 . The ceiling fan as claimed in  claim 10 , wherein said blade module further includes a mounting frame connected to said rotor seat and a plurality of blade supports arranged equiangularly about and mounted to said mounting frame, said fan blades being respectively mounted to said blade supports.