Film packing device capable of replacing gears

A film packing device comprising:

• a handle;
• the handle comprising an upper handle end, a lower handle end, a coupling rod, a base, an upper casing and a lower casing;
• the upper handle end and the lower handle end extending in the same direction;
• the coupling rod being provided on the upper handle end;
• the base being provided on the lower handle end;
• the upper casing being detachably connected with the coupling rod;
• the lower casing being detachably connected with the base;
• a film application unit;
• the film application unit being pivotally connected with the coupling rod and the base;
• a roller unit;
• the roller unit being pivotally connected in between the base and the coupling rod;
• the roller unit comprising a first roller and a second roller;
• the first roller comprising a first upper roller end, a first lower roller end, a first upper gear assembly and a first lower gear assembly;
• the first upper gear assembly being disposed on the first upper roller end;
• the first lower gear assembly being disposed on the first lower roller end;
• the first upper gear assembly and the first lower gear assembly being identical to each other;
• the second roller comprising a second upper roller end, a second lower roller end, a second upper gear assembly and a second lower gear assembly;
• the second upper gear assembly being disposed on the second upper roller end;
• the second lower gear assembly being disposed on the second lower roller end;
• the second upper gear assembly and the second lower gear assembly being identical to each other;
• the first upper gear assembly and the second upper gear assembly meshing with each other;
• the first lower gear assembly and the second lower gear assembly meshing with each other;
• the first upper gear assembly and the second upper gear assembly being accommodated in between the upper casing and the coupling rod;
• the first lower gear assembly and the second lower gear assembly being accommodated in between the lower casing and the base;
• the first upper gear assembly comprising a first upper axle gear and a first upper drive gear;
• the first lower gear assembly comprising a first lower axle gear and a first lower drive gear;
• the second upper gear assembly comprising a second upper axle gear and a second upper reduction gear;
• the second lower gear assembly comprising a second lower axle gear and a second lower reduction gear;
• the first upper axle gear being fixed to the first upper roller end;
• the first lower axle gear being fixed to the first lower roller end;
• the second upper axle gear being fixed to the second upper roller end;
• the second lower axle gear being fixed to the second lower roller end;
• an outer toothed portion of the first upper axle gear meshing with an inner toothed portion of the first upper drive gear;
• an outer toothed portion of the first lower axle gear meshing with an inner toothed portion of the first lower drive gear;
• an outer toothed portion of the second upper axle gear meshing with an inner toothed portion of the second upper reduction gear;
• an outer toothed portion of the second lower axle gear meshing with an inner toothed portion of the second lower reduction gear;
• the outer toothed portion of the second upper reduction gear meshing with the outer toothed portion of the first upper drive gear;
• the outer toothed portion of the second lower reduction gear meshing with the outer toothed portion of the first lower drive gear;
• numbers of teeth on the outer toothed portion of the second upper reduction gear being different from numbers of teeth on the outer toothed portion of the first upper drive gear;
• and
• numbers of teeth on the outer toothed portion of the second lower reduction gear being different from numbers of teeth on the outer toothed portion of the first lower drive gear.